Synthesis and Luminescent Properties of Sr2CeO4: M Phosphors

Synthesis and Luminescent Properties of Sr2CeO4: M Phosphors
　　The search for phosphors started more than 100 years ago and applications have been developed extensively in the fields of luminescence, display and detection. The green and red emissions are produced by the f-f transitions of Tb3+ and Eu3+, the relevant phosphors have been commercialized. But comparable commercial materials for the blue emission are still lacking. In 1998, a new rare-earth luminescent material Sr2CeO4, possessing one-dimensional chains Ring neodymium magnet of edge-sharing CeO6 octahedron, was synthesized successfully and identified through combinatorial technique by Dinelson et al. Its luminescence is originated from charge-transfer transition (CTT). This phosphor emits blue-white fluorescence by excitation through the X-ray, cathode ray and ultraviolet ray. It is well known that the search for blue phosphors is of particular importance because of the limited number of stable blue luminescent materials available.
　　Therefore, Sr2CeO4 has good potential for application as a blue phosphor in lamps and field emission displays, etc.In our present work, the Sr2CeO4 phosphors with good photoluminescence were synthesized successfully through combustion method, sol-gel method and sol-gel auto-combustion method. TG-DTA, XRD, SEM and photoluminescence spectra were used to investigate the decomposition process of the precursor, and the formation process of Sr2CeO4, http://www.chinamagnets.biz/ microstructure and luminescent properties. The results show that the pure orthombic Sr2CeO4 phosphors can be obtained under proper conditions. Excitation spectumn is a wide band in the range of 200～400nm with two peaks. Emission spectrum is a broad band too. It is located in the range of 400～600nm with one peak. It is interesting that the position of the peaks show some differencese when Sr2CeO4 phosphors were obtainted by different methods.For Sr2CeO4 phosphors synthesized by the combustion process, the two excitation peaks are located at 298nm and 350nm respectively; the former is stronger than the latter. When stearic acid is used as fuel, the main emission peak is at 470nm. Meanwhile it is found that the

The Effect of Rheological Characteristics and Ingredients of Ceramic Slurry on Properties of Ceramic Foam Filter

The Effect of Rheological Characteristics and Ingredients of Ceramic Slurry on Properties of Ceramic Foam Filter
　　The study successfully prepared a high-quality ceramic foam filter using Al 2 O 3 as the main raw material, and kaolin, talcum powder and SiO2 as the additives by the polymeric sponge impregnation process.This study proceeded the theoretical and experimental analysis by referring to a large quantity of interrelated data, both domestic and international: first, tested ceramic slurry by a rotating rheometer and analyzed several influencing factors on rheological Ball Neodymium Magnets characteristic; then analyzed the experiment of reducing sintered temperature by high-temperature physical properties analysis and DTA on ceramic samples;after made a array of analysis towards the performances of the samples by testing open porosity, bulk density, banding strength and thermal shock resistance.etc; finally observed and analyzed the phases and microstructure of the samples using XRD and SEM.The optimal properties of slurry was required by impregnation a polyurethane sponge with ceramic slurry.
　　The high solid content, equality and stabilization, excellent rheological slurry can be obtained by using proper additives. In the study, the best ceramic slurry can be obtained by adding 0.2% quality content PAM; with the increase of the solid content, the viscidity of was higher; with the increase of shearing speed, the viscidity behavior index decreased, which http://www.chinamagnets.biz/ was typically pseudoplastic and the shear-thinning characteristics; the viscidity of ceramic slurry can be induced to shear-thinning and depend on time. The suspension exhibits positive thixotropy which satisfies impregnation.The experiment results proved that the starting liquid temperature of the sample without additives was about 1325℃and the starting liquid temperature of the sample adding Y 2 O 3 ,CeO 2 and MgO,TiO2 was about 1290℃. So additives for sinter can reduce sinter temperature.The important effect of sample properties for adding Y 2 O 3 , CeO2 and MgO,TiO2 were discovered in study. The contrast to effect of sample properties such as open porosity, bulk density, banding strength and thermal shock resistance was listed as follow: (Y 2 O 3 +CeO 2 )+(MgO+TiO 2 )>(Y 2 O 3 +CeO 2)

Study on Self-Propagating Synthesis of the Doped SrAl2O4 Rare-Earth Long After-Glowed Phosphors

Study on Self-Propagating Synthesis of the Doped SrAl2O4 Rare-Earth Long After-Glowed Phosphors
　　62 codoped SrAl2O4 long after-glowed phosphors with 6 series are synthesized by SHS method using urea-nitrate solution as media at 600 ℃. rare earth magnets They are SrAl2O4: Eux2+, Dyy3+, (x:y=1:1, x:y=2:1), SrAl2O4: Eu0.01252+, RE0.01253+ (RE3+=Ce3+、Pr3+、Nd3+、Tb3+、Dy3+), SrAl2O4: Eu0.01252+, M0.0125(M=Li+, Be2+, Cd2+,Mn2+, Cu2+, Ag+, Zn2+, Pb2+) SrxM(1-x)Al2O4: Eu0.01252+, Dy0.01253+ (M=Li+, Be2+, Cd2+, Zn2+, Pb2+), SrAl2O4: Eu0.01252+,Dy0.01253+, M0.0125 (M=Mn2+, Cu2+, Ag+, Zn2+, Pb2+) , SrAl2O4: Eu0.01252+, Dy0.01253+, RE0.01253+ (RE3+=Ce3+、Pr3+、Nd3+、Tb3+), luminescent and after-glowing features are tested . Morphology of the sample presents a state of laxity and porous . The sample exhibits an intensity emission peak at 514 nm and the excitation http://www.chinamagnets.biz/ spectra consists of 290-360nm broad peaks .Among the five RE3+ ions with +4 valence discussed in this paper, Tb3+ and Dy3+ lay the most effect on luminance and after-glowed time respectively . The material with SrAl2O4: Eu0.01252+, Dy0.01253+ has good luminance and proper after-glowed

Preparation and Characteristics of Nanometer Cadmium Oxide Thin Films with Dysprosium Doping

Preparation and Characteristics of Nanometer Cadmium Oxide Thin Films with Dysprosium Doping
　　We prepare pure CdO and Dy-doping CdO thin films by vacuum evaporate-deposition on different substrates, such as glass, Si and SiO2,furthermore take heat treatment the films. Then test the characteristics of films on structure, surface, electric strong magnets conduction, optics property, etc.. So as to analyze the influences from the process conditions, contents of Dy, different substrates as well as heat treatment temperature and time on crystalline structure, crystalline grain dimension, optics and electrical characteristics of samples.The experiments shows that using the high pure CdO powder as evaporate source to prepare CdO thin films on different substrates and then oxidizing and heat treatment, can obtain the films with good performance. The experiment also shows that the best heat treatment condition of the samples on glass substrates is T=550 ℃, t =20min; And that on silicon and dioxide silicon substrates is T =650℃, t =30min. The samples all have a preferred orientation http://www.chinamagnets.biz/ growing trend along (111) direction and uniform crystalline grain dimension. Dy-doping can influence the growth of crystalline grain and the average dimension of crystalline grain varies

Study of the Rare Earth Doped Phosphate Glass Ceramics

Study of the Rare Earth Doped Phosphate Glass Ceramics
　　The transparent phosphate system glass-ceramics was synthesized by the melting method and annealing technique. The crystallization heat-treated schedules were based on DTA results. The compositions and structure of crystal phases were determined on the base of XRD results. The main crystal phase is Al2SiO5 that belongs to the transparent phosphate system glass-ceramics which contains SiO2. The main crystal phase are AlPO4 and Al2P6O18 that belong to the transparent phosphate system glass-ceramics which is without SiO2. The P2O5 system glasses with magnet lifter good crystallization ability were nucleated at 400℃670℃and crystallized at 530℃740℃. The microstructure of the transparent phosphate system glass-ceramics was characterized by SEM. The grain size range is 1.66436.05nm. The grain size range of P5 is 70.34149.05nm. The fluorescence spectra of the base and glass-ceramic heat-treated at different schedules were measured. The influences of crystal phase compositions and microstructure were determined. Phase compositions and grain size of glass-ceramics were found to affect their fluorescent characteristics considerably. Three main fluorescence bands centering at about 878nm,1054nm and 1330nm were observed, which were correspondent to the transitions http://www.999magnet.com/ of 4F3/2→4I9/2、4F3/2→4I11/2 and 4F3/2→4I13/2,respectively. The fluorescent intensity of glass-ceramics is stronger than the fluorescent intensity of base glass. The transmittance in the infrared region is obtained and compared. The transmittance of P5 is at 6975%, it is higher than others. P5 is the best system to study.

Study on Manufacture and Microwave-Absorption Properties of the New Type Absorption Material Nd8-XYFe84.5+XB6.5 (x=0, 0.5, 1)

Study on Manufacture and Microwave-Absorption Properties of the New Type Absorption Material Nd8-XYFe84.5+XB6.5 (x=0, 0.5, 1)
　　A novel absorption material is obtained after vacuum smelting,steelball pulverizing and proper annealing disposal.At the same time,their microwave absorption property is studied.The result shows that the absorption property of the material which pulverized at different time is different;The anneled and steelball absorption property is better than the one without anneled,and the material absorption property is best when annealed time and the content of Fe are proper.Ball Neodymium Magnets At the same time,we have also studied the anti-oxidant property change of the material when doped with yttrium.In the chemical proportion of molecular of Nd8xYFe84.5+xB6.5(x=0,0.5,1), material absorption property is best when x=0.5 without annealed,and the highest absorption value is 36.843dB,compared with x=0,1,the value increases obviously.The above indicates that the absorption property of these materials doesn’t change as the mount of Fe regularly,only doping proper a mount of Fe can improve its microwave absorption property.
　　The absorption property of the annealed material increases obviously than the one without annealed,When annealed for 15min,the absorption property is at best,the highest absorption value is 137.36dB,and the average absorption has the height of 10dB than the one annealed for 10min or 20min.Therefore,the annealed time can get a proper value.After the sample pulvevized at different time(t=6h,8h,10h,12h),the microwave absorption property is best when the sample pulvevized for 8h.The above indicates that the absorption property of these materials doesn’t change as the time of pulverized regularly,but there exists a matching time.The extent of weakening of the absorption property value of the sample that doped with yttrium is smaller than the http://www.chinamagnets.biz/ one without doped with yttrium in the air after a period of time.Therefore,the anti-oxidant property is strengthened when the sample is doped with yttrium.In order to study the microwave-absorbing mechanism,imagionary part of permeability,dielectric constent and XRD spectrum of the sample are measured.The results of experiments indicate that the frequency corresponding to the peak of imagionary part of permeability is close to the one corresponding to the peak of absorption when the sample without annedled,and their changing rules of the peak of imagionary part of permeability and absorption change with frequency are similar.Therefore,the absorption property of the sample without annealed rests on imagionary part of permeability,but the frequency corresponding to the peak of imagionary of dielectric is close to the one corresponding to the peak of the absorption.And their changing rules of the peak of imagionary part of dielectric constent are similar when the sample annealed.From the XRD spectrum,we can see that the sample formed the configuration that the oxid and metal particulate distribute symmetrically according to cubage,which provides a finer absorbing way for the sample.

Preparetion, Microstructure and Mechanical Properties of Tial Based Alloy Sheet

Preparetion, Microstructure and Mechanical Properties of Tial Based Alloy Sheet
　　TiAl based alloys are extensively investigated in recent years because of theirlow density, high strength, excellent oxidation and creep resistance. TiAl sheetscan be used not only as structure materials but also as function materials. Withthe development of TiAl based alloys application, it is urgent to fabricate TiAlsheets. However, the major factors limiting structural applications of thismaterial are their ambient temperature brittleness and poor workability. In thispaper TiAl sheets are obtained with a new method,which involve preparing ingot,caned forging and hot-pack rolling. neodymium magnets The property of the TiAl based alloy sheetproduced was test.The ingots were prepared by Induction Skull Melting(ISM). The resultsindicate that the as-cast alloy consists ofα2,γ, B2 and YAl2 phases. Thecrystalline grains of as-cast alloy are coarse lamellar structure. Element V existsin B2 phase, and of element Y exist in YAl2phase. The mechanical property testsshowed that the plasticity of as-cast alloy is very low. At room temperature,σsandσb are 419.5MPa and 510.6 MPa, respectively, andδis 0.5%. At 700℃,σsandσbare 342.6MPa and 442.7MPa,respectively, andδis 5.7%.TiAl based alloy pancake is prepared by caned forging. The as-forged alloyconsists ofα2,γ, B2 and YAl2 phases. Microstructure observation indicated thatthe amout of lamellar structure reduces apparently, the grain size is finer, and Y-rich phases are broken up or elongated as strap shape after deformation andrecrystallization.At room temperature,σsandσbreach 551.2MPa and 613.8 MPa,respectively, andδis 1%. http://www.chinamagnets.biz/  By using hot-pack rolling, the TiAl base alloy sheets wereprepared with asizeof 340×(65~110)×2mm. After rolling, the Y-rich phase disperses in the matrixmore uniformly.The as-rolled structure is coarser than the as-forged structure. Atroom temperature,σs andσb are 509.1MPa and 611.7 MPa, respectively, andδis1.2%. At 700℃,σs andσb are 414.6MPa and 488.8 MPa, respectively, andδis7.9%.

高压钠灯用新型储备式电极的研究

高压钠灯用新型储备式电极的研究
　　In the entire Electricity Consumption,electricity consumption on road illumination takes more than 30%proportion,which,along with the domestic agenda of urbanization in China,is continually increasing.HPS is recognized as one the most widely applied and the most lumen-efficient lamps used on road illumination.To carry through the state’s policies of energy saving and emission reduction,at least 10%of the electricity consumption used on illumination should be saved according to the eleventh Five-Year Plan.That further increase the lumen efficiency and longevity of currently used HPS,therefore,should remains the very significance for long lasting flourishing of society.In this sense,to investigate and develop a new electrode with better performance must be viewed as the very first step leading to that aim.The performance of the conventional electrode coated with oxides electron powders,the most frequently used one,is weak in several aspects:bad durability to ion bombardment,rare earth magnets high work function and bad start-up properties.At the same time,the amount of emitting material is little and cannot be controlled exactly.All of the above has greatly restricted the synthesis capability of HPS.In this sense,aiming to discover a brand new type electrode which embraces a relatively lower work function and more stable emission property remains the most promising direction in the research of HPS.Based on the investigation of rare earth metal-W electrode and the traditional dispenser Ba-W electrode,this research inaugurates a brand new dispenser electrode that is innovative both in structure and combination.
　　This new dispenser electrode primarily includes a columniform sinter and a pure tungsten rod located in the middle of the tinter.The columniform sinter is made of several compounds of W,BCT and Y2O3-La2O3-CeO2,adequately according to prescription;suppress those mixture to a column and mount a tungsten rod axially in the column and finally sinter these elements in high temperature for several times.SEM,EDAX,voltage,luminous flux and some other photoelectricity parameters for many kinds of HPS with different prescriptions and technics have been measured.For 250W HPS,result shows that the luminous flux at 2000h is 96.32%of the original, the http://www.chinamagnets.biz/ lumen decay is smaller than National standard(90%at 2000h) even at 5000h, when the lumen maintenance is 92.49%.Lamp voltage increased to 0.73V/1000h, much smaller than the international advanced level(1.5V/1000h) and domestic advanced level(3V/1000h).Therefore,we can estimate that the lifetime of new dispenser electrodes will be more than 3 times longer than that of the original domestic HPS lamp and twice as much as the original international HPS lamp.Due to the good performance on ignitor,the pressure of starting gas Xe in arc tube can increase from 4kPa to 36kPa,so the new HPS lamps have about 20%more lumen output than the national standard.Such results reveal that the new HPS embraces strong potentials both in energy saving and material saving.

Effects of Mineral Composite Materials for Far Infrared Radiation on Oil Consumption and Air Pollutants Emission of Oil-Burning Boiler

Effects of Mineral Composite Materials for Far Infrared Radiation on Oil Consumption and Air Pollutants Emission of Oil-Burning Boiler
　　Aimed at the petroleum resources shortage and environmental pollution, new types of mineral composite materials with far infrared radiation were successfully prepared to be applied to oil-burning boiler, which could improve the physicochemical Block neodymium magnet properties of fuel oil, enhance the combustion efficiency and reduce the air pollutant emission. The far infrared radiation performance of the mineral composite materials and their influence on the oil consumption and air pollutant emission were systematically investigated in this thesis, especially the influence mechanism of mineral composite materials on the combustion of fuel oil.The ceramic materials with far infrared radiation were prepared using tourmaline, rare earth and clay as raw materials.
　　When the proportion of mineral material, rare earths and clay was 15:1:4, the ceramic materials heat-treated at 900℃for 2h exhibited the highest infrared radiance of 0.91. When this material used in RBS·VH-1.5 boiler, the oil-saving ratio could reach 1.23%, and the contents of CO and NO in the exhaust gas could reach 25.6% and 9.2%, respectively.The organic/inorganic composite materials with far infrared radiation were prepared using tourmaline, rare earth and resin as raw materials. The far infrared radiation performance of the composite materials and their influence on the oil consumption and air pollutant emission were investigated. The experiment results showed that the as-prepared composite materials had the highest infrared radiance of 0.93 when the ratio of mineral http://www.chinamagnets.biz/ material to resin was 4:6. The oil-saving ratio of the boiler using this composite material could reach 3.78%, and the contents of CO and NO in the exhaust gas were 15.9% and 14.5%, respectively.The influence mechanism of mineral composite materials on the improvement of combustion efficiency and reduction of air pollutant emission were studied in this thesis. It was believed that the far infrared radiated by the mineral composite materials could enhance the molecular energy and reduce the surface tension of diesel oil, thus leading to the improvement of its atomization quality and the reduction of air pollutant emission.

Research on Purifying NO by Active Carbon Fibers Loaded Lanthanon Oxide

Research on Purifying NO by Active Carbon Fibers Loaded Lanthanon Oxide
　　Active carbon fibers (ACF) have strong adsorbent because of their large specific surface areas and vast micro-pores that most of them distributing on the surface of ACF. And there have been proved up a large amount of Lanthanon minerals in our country, Ball Neodymium Magnets the Lanthanon have widely potential application use in environmental catalysing and etc. for their active and special chemical characters. This paper introduces the NOx actuality pollution of our country and its damage and the character and the preparation of ACF and the physical and chemical characters of Lanthanon, and then it is discussed that the technique and principle and international research and application actuality on purifying NOx. And the purpose of this paper is to find an effective and economical loaded model catalyzer on purifying NOx, and at the same time to find a new way to utilize the ACF and the Lanthanon together.It’s the first time that the catalyzer is prepared by integrating the ACF physical character with the Ln2O3 chemical character. Firstly, some La2O3/ACF and Ce2O3/ACF were prepared by the ACF loaded La2O3 and Ce2O3, and according to the demand of the experiment, the blank ACF and the HNO3/ACF and some CuO/ACF were also prepared. In the following experiment their activity were studyed and compared.In order to study the impact degree on purifying NO by the following four important factors as the R2O3 loaded quantity(R2O3%) and the temperature(T/℃) and the mixed gaseous airspeed(V/m3?h-?m-3 or h-) and the oxygen’s bulk percent in the mixed gases(O2%), the L9(34) experiment was designed.
　　The experiment results showed that the most important factor in the catalysing experiment was the temperature; it was followed by the oxygen’s bulk percent in the mixed gaseous, and the mixed gaseous airspeed then was and the R2O3 loaded quantity. And at the same time what we also could find from the experiment were that the factors’level that we should setted were that the oxygen’s bulk percent in the mixed gaseous was 5% and the mixed gaseous airspeed was 5000 h-, because there were so many possibility in the experiment about the temperature and the R2O3 loaded quantity that we couldn’t give the factors level before more experiments were done. http://www.chinamagnets.biz/   According to the results of the L9(34) experiment, we mixed the gas by the following bulk percent ratio that the NO%=0.1% and the NH3%=0.11% and the O2%=5% and the others was N2, and the mixed gaseous airspeed was 5000 h-, and the catalyzer’s loaded quantity normally was 0.5000 g, and the temperature range was 150450℃(according to the experiment the most high temperature could be 600℃). In these environments the activity experiments on purifying NO by the blank ACF catalyzer and the HNO3/ACF catalyzer and the CuO/ACF catalyzers and the La2O3/ACF catalyzers and the Ce2O3/ACF catalyzers were carryed out. And then the catalyzers’activity and stability were compared transversely and lengthways.
　　The experiment results showed that though the HNO3/ACF catalyzer had better activity in lower temperature, but its stability was too bad; and the 20%La2O3/ACF had better activity and stability at higher temperature, but its activity in lower temperature should be improved; and the 10%Ce2O3/ACF had the best holistic activity and stability; and though the CuO/ACF catalyzers had been studyed for many years, but its the holistic activity was the worst among the Ball Neodymium Magnets  catalyzers. And furthermore the catalyzers’activity on purifying NO of the 20%La2O3/ACF and the 10%Ce2O3/ACF was over 95% when the temperature was over 300℃, and the catalysing stability of the 20%La2O3/ACF was largely improved and reached 8h at 200℃by loaded 1.0000g catalyzer. So we could get the conclusion that the 20%La2O3/ACF and the 10%Ce2O3/ACF were the best catalyzers of all.At last, the TG and XRD and SEM and FT-IR experiments were carryed out to estimate the selected catalyzers’physical and chemical characters. And the results of physical and chemical character experiments not only testifyed the results of the compared experiments but also provided theoretic base of the catalyzers’improvement.

Effect of Powder Metallurgy Processes by High Energy Ball Milling on the Microstructure and Properties of Aluminum Matrix Composites

Effect of Powder Metallurgy Processes by High Energy Ball Milling on the Microstructure and Properties of Aluminum Matrix Composites
　　The powder fabricating process for particle reinforced Aluminum matrix composites was optimized by orthogonal and single experiment. The results indicate that three procedure factors, velocity, time for milling and the amount of process control agent (PCA), are important for particle size and properties. The optimal process parameters have been proposed. They are 280rmp and 15h with 4 %( wt) PCA. Based on this, two key problems were investigated further in this paper.First, choosing cheaper industrial alumina(γ-Al2O3) as reinforcement,γ-Al2O3/Al composites Neodymium Magnets was fabricated successfully by powder metallurgy. Thisγ-Al2O3/Al composites was treated by water-logging method. Experiment showed that its hardness was nearly 4.2 times higher than before water-logging treatment, reached to 103.8HB, and its wear resistance increased about twice. Mechanism analyses indicated that the properties, improvement was caused by several factors which worked together. There were densification, falling down of system energy, improvement of interface, and dispersion of reinforcement. At last, a new reinforce model, The Second Reinforce Model, was put forward.Second, SiCp/Al composites with vary rare earth oxide (CeO2) was fabricated by means of powder metallurgy successfully. Its properties and microstructure were studied by equipments and the influence of RE content was http://www.999magnet.com/ analyzed. The results show that RE can improve the wearing performance and hardness of the composite. The optimal amount of RE is 0.4 %( wt), overmuch added will induce a bad result. Mechanism analyses show that the improvement was caused by the addition of CeO2; it can restrain the interface reaction of SiCp/Al.

VUV-excited Luminescence Properties of MAl2B2O7: Re(M=Sr, Ba, Ca; Re=Eu～(3+), Tb～(3+), Eu～(2+))

VUV-excited Luminescence Properties of MAl2B2O7: Re(M=Sr, Ba, Ca; Re=Eu～(3+), Tb～(3+), Eu～(2+))
　　In recent years, more attention has been paid to PDP(Plasma display panel)because of its potential market in the illumination. Special attention has been paid to the development of new and efficient VUV-excited phosphors. On the other hand, borates are of interest as host lattices for luminescent ions, because of their large band gap. Based on this consideration, it is valuable to investigate the alkaline borate family. In this paper, The VUV excitation and luminescence characteristics of MAl2B2O7:Re(M=Sr, Ba, Ca; Re= Eu3+,Tb3+, Eu2+) have been studied.In this Block Neodymium magnets work, a series of powder samples of MAl2B2O7:Re(M=Ca,Sr,Ba; Re= Eu3+,Tb3+, Eu2+)was prepared under a reducing atmosphere by solid-state reaction. . The X-ray powder diffraction data of MAl2B2O7:Re are in agreement of JCPDS standard card which indicates that single-phased phosphor can be obtained in such synthesis process.
　　The excitation spectrum of MAl2B2O7: Eu3+ (M=Sr, Ba, Ca) are composed of two broad bands. One band in the range from 130 nm to 170 nm is attributed to the borate groups, and the other band at 230 nm is due to the charge-transfer state (CTS) of the Eu3+ ion. The excitation peak shifts from 167nm to 172nm when the Sr2+ ions are completely replaced by the Ba2+ and Ca2+ ions. It is obvious that the wavelength positions of the excitation bands http://www.999magnet.com/ depend much more on hosts. The lattice parameters of the phosphors increase and the crystal-field strength decrease with increasing of the ionic radius of Ca2+, Sr2+ and Ba2+.Because Eu3+ ions doped into CaAl2B2O7 occupy centrosymmetric site, the emission of magnetic dipole transition 5D0→7F1 is stronger than electric dipole transition. As Eu3+ ions doped into MAl2B2O7 (M=Sr, Ba) occupy Ba2+ or Sr2+ sites which is non-centrosymmetric site, so that the emission of electric dipole transition 5D0→7F2 is stronger than magnetic dipole transition in those series sample. The strong emission line at 613 nm is due to the hypersensitive electric dipole transition of 5D0→7F2. The weaker emission around 592 nm is due to the magnetic dipole transition 5D0→7F1.As for MAl2B2O7:Tb3+ (M=Sr, Ba, Ca) the VUV excited spectra consists of one broad band in the range from 120 nm to 170 nm and the band peaking around 226 nm,

Preparation and Absorbing Mechanism of Modified Nanometer BaFe12O19

Preparation and Absorbing Mechanism of Modified Nanometer BaFe12O19
　　The microwave absorption material is playing the extremely vital role in the military and civil. Applies generally in the stealth airplane, the cannon, the tank and so on,simultaneously the more and more many attenuating material has used in electromagnetism equipment such as microwave communication, microwave darkroom, computer, microwave oven. The ferrites absorbing material is the double duplicate medium which has the certainly coefficient and the dielectric loss, Block Neodymium magnets and has certainly magnetic conductivity and magnetism lose.,hexagonal ferroxdure becomes the key point by its fine frequency sound characteristic which the people studied in recent years.
　　This experiment used the Sol-gel SHS to obtained the M-type hexagonal Ba-ferrite and BaRexFe12-xO19 (Re=La, Nd) nanocrystals through the control gelatin. When pH≈7, citric acid∶Metallic ion (mol ratio) =1∶1, in forms the sol in the process to join the supersonic vibration to be possible to cause the ferrite particle size to change obviously small, the grain size reduces from 40nm to 10nm about. The experiment showed that the speed of heating-up and the sintering temperature have great influence on the grain structure and composition of the nanometer Ba-Ferrite. The M-type Ba-ferrite was obtained on 700℃, and the higher of the sintering temperature the better of the power’s crystallinity. The sheet-like nanoparticles could be obtained in the sintering at 10℃/min, while nanorods were obtained at 40℃/min.Used the Sol-gel SHS method to prepare http://www.999magnet.com/ BaRexFe12-xO19 (Re=La, Nd), the experiment indicated that the rare-earth element seeped in the ferrite crystal lattice , and the crystal constant had the fill-out tendency. The rare earth doping has not changed the superficial appearance of the Barium ferrite. Used the method which non-homogeneous phase chemistry precipitated to prepare cladding 20mass% Ni(OH)2 and the TiO2 ferrite powder. The clad forms the nanometer level pellet also the quite even gable in the ferroxdure surface, thus gets up the modified ferrite surface performance effect.The Fe3+ in M-tapy BaFe12O19 most outer layer 5 electrons occupy 5 spatial tracks separately. The hysteresis cycle test indicated that the barium ferrite is one

Characteristics and Genesis Studying of Co-Rich Crust from West Pacific

Characteristics and Genesis Studying of Co-Rich Crust from West Pacific
　　The Co-rich crusts contain many rare and precious metals, such as Co, REE andtrace element except for the main elements Mn, Fe, Cu and Ni etc. Because of theusually shallow depth of marine in the deposit area of the crust, which will lead tolower exploration costs and less pollution to marine environment, many countrieshave been investing large capitals in Special shape NdFeB magnets  exploring and researching of submarine Co-richcrusts since 1980s.In this study, detailed observation under microscope and systematical studies ofgeochemical of Co-rich crust by some modern analytical methods, which includeEPMA analysis, REE analysis, ICP-MS analysis, XRF analysis, were carried out, andpreliminary discussion that how the Co-rich crust deposited.The analytical results show that:1. The petrologic studying indicates that pyrochroite, quartz, anorthite andfluorapatite are widely distributed in the Co-rich crust. The present of the large ofpyrochroite infers that the forming process of the Co-rich crust once underwent thereductive environments.
　　2. Electric microprobe analysis provides the evident for hydrogenic originbecause of the quite positive correlation between the element Co and Mn in thesample MID and CLD. Correlation coefficients are 0.66 and 0.79 respectively. Thepositive correlation http://www.999magnet.com/ between Co and Mn is the typical characteristic of hydrogenicorigin.3. Trace element analysis shows that there are many trace elements havepositive correlation with the element Co. The strongest positive correlation elementis U with 0.867 of coefficient. Trace element can be divided into three groups withthe result of cluster analysis. (1) Sc, Rb group which include the element Sc, Rb,Cs, Th, Zr, Hf, Ta and Cr. (2) Co, U group which Co, U, Ni, Zn, Ga, Sn, Cu, Ba andZr etc. (3) Y group, only one single element Y. After matching the sample’s curvedistribution with the data of other area which are the continental crust, mantle andmarine crust.4. There are great total rare earth element content (∑REE = 1215.86 × 10 – 6 ~2664.23×10-6), positive Ce anomaly (543.68×10-6~1026.40×10-6). Suggesting that theCo-rich crust was once underwent an oxidizing atmosphere. The distribution curveanalysis indicates that the metallogenic elements deposited from upper continentalcrust.

The Biological Effect of Static Magnetic Field on Cultured Maxillofacial Skeletal Muscle Cells in Vitro

The Biological Effect of Static Magnetic Field on Cultured Maxillofacial Skeletal Muscle Cells in Vitro
　　Objectives: The purpose of this study was to observe the biological effects of static magnetic field(SMF)at 971.77mT produced by the rare earth magnets used in orthodontics on cultured maxillofacial skeletal muscle cells, and to discuss the biological effects of the static magnetic field on the remodeling of maxillofacial skeletal muscle tissues during the orthodontics treatment.Materials and Methods: the maxillofacial skeletal muscle cells were isolated and cultured in vitro from the neonatal Sprague-Dawley rat, the cultured SD maxillofacial skeletal muscle Cube neodymium magnet cells of the third generation were treated with SMF for seven days. Cell counting to draw a growth curve ,and calculate the doubling time of maxillofacial skeletal muscle cell; by scanning transmission electron microscopy(TEM) to observe the ultrastructural change of the cell; the method of MTT was employed to evaluate the level of proliferation ,the parameters regarding the variation of the cell cycle were detected with the flow cytometry (FCM).
　　Result: after the treatment with SMF for seven days, the growth curve show that the cells which under the SMF have a well adaptability , as compare to the control group and the blank group ,the number of the maxillofacial skeletal muscle cells exposed to 971.77mT SMF was significantly higher at the same day(P< 0.001), there was no difference between the control group and the blank group, for the doubling time of maxillofacial skeletal muscle cell, the experimental group was more early than the control group and the blank group; by scanning TEM ,there was no http://www.chinamagnets.biz/ pathologisch changes of the morphocytology from the experimental group and the blank group ,but the experimental group has more activate free ribosomes, glycogen, Golgi apparatus, bioblast, rough endoplasmic reticulum and microfilament compare to the blank group; the amount of cells proliferation determined by MTT after cultured for 48hrs and 72hrs , the proliferative rate of the experimental group was significantly higher than the blank group .Conclusion: SD maxillofacial skeletal muscle cells which under the SMF have a well adaptability; and there is no pathologisch changes to the morphocytology of the cells , the rare earth magnet is safe to use in the orthodontics ; also the SMF has the function to enhance the proliferation.

Microstructure and Mechanical Behavior of Hot-Extruded Mg-Mn-Zn-RE Alloys

Microstructure and Mechanical Behavior of Hot-Extruded Mg-Mn-Zn-RE Alloys
　　As a lightweight structural material, magnesium alloys will get more widely applied in automotive industry. It has received much more concerning how to improve mechanical properties of magnesium alloys with an increase in usage of magnesium alloys. It is obvious that to develop new wrought magnesium alloys can meet the requirement of mechanical properties for automobile structural materials and ensure magnesium alloys to be applied in automobile industry more and more. In this investigation, both microstructures and mechanical properties of hot-extruded Mg-Mn-Zn(-RE) alloys have been studied, and the influence of RE additions on microstructures and mechanical Block neodymium magnet properties of hot-extruded Mg-Mn-Zn alloy has been identified in order to provide reliable theoretical reference for both engineering application of hot-extruded Mg-Mn-Zn(-RE) alloys and development of new wrought magnesium alloys containing RE elements.The results of microstructural observation reveal that the addition of RE elements can effectively refine the grains in hot-extruded Mg-Mn-Zn alloy. For hot-extruded Mg-Mn-Zn alloy, the addition of 2% Y can reduce the average grain size from 50 urn to 10 (am, while the addition of 1% Ce can decrease the average grain size from 50μm to 15μm.The results of tensile experiments reveal that both ultimate tensile strength and yield strength of hot-extruded Mg-Mn-Zn-RE alloy at elevated temperatures can get significantly enhanced due to the addition of RE elements.
　　For example, at 150℃, when the content of either Y or Ce equals to 2%, the hot-extruded Mg-Mn-Zn-RE alloys exhibit the highest ultimate tensile strength and yield strength. At 200℃, when the content of Y or Ce reaches to 3%, the highest ultimate tensile strength and yield strength can be attained for the hot-extruded Mg-Mn-Zn-RE alloys. Moreover, the hot-extruded Mg-Mn-Zn-1 Ce alloy shows the greatest fracture elongation at room temperature and 200℃, compared with other Mg-Mn-Zn-Ce alloys. The results of low-cyclic fatigue tests show that the hot-extruded Mg-Mn-Zn alloy exhibits cyclic strain hardening at all total stain amplitudes. The hot-extruded Mg-Mn-Zn-1 Ce alloy exhibits cyclic strain hardening followed cyclic stability at the lowest total strain amplitude http://www.chinamagnets.biz/ used in this investigation, while show cyclic strain hardening at other total strain amplitudes. For the hot-extruded Mg-Mn-Zn-2Y alloy, either cyclic strain hardening or stable cyclic stress response can be observed at the higher total strain amplitudes, and however, cyclic strain softening can be noted at the lower total strain amplitudes.
　　For the hot-extruded Mg-Mn-Zn(-RE) alloys, the relation between elastic strain amplitude, plastic strain amplitude, and reversals to failure shows a monotonic linear behavior, and can be well described by the Basquin and Coffin-Manson equations, respectively. Moreover, a linear relation between tensile hysteresis energy and fatigue life can be also noted for hot-extruded Mg-Mn-Zn(-RE) alloys.The fractography shows that the tensile fracture surfaces Block neodymium magnet of hot-extruded Mg-Mn-Zn-RE magnesium alloys exhibit typical ductile fracture feature. For the hot-extruded Mg-Mn-Zn-RE magnesium alloys, cracks initiate transgranularly at the surface of fatigue specimens and propagate in a transgranular mode under the low-cycle fatigue loading condition.

Geochemical Characteristics of Magmatites and Metallogenic Progonosis in Qianjin Area, Heilongjiang Province

Geochemical Characteristics of Magmatites and Metallogenic Progonosis in Qianjin Area, Heilongjiang Province
　　Yichun-Yanshou metallogenic belt of Heilongjiang Province is an important centralized deposit area in Heilongjiang Province even in our country, which is the joint of Songnen-Xiaohingganling massif and Jiamusi massif according to geotectonic position, which is one of the orogens that undergoes the longest history of development and possesses frequent tectonic-magmatic activities in northeast China. Qianjin area is lain in the center to west of Yichun-Yanshou metallogenic belt and tectonic-magmatic complex. With the further research to this area, many significant geological Ball Neodymium Magnets subjects left to be resolved, such as the forming time of magmatites, their sources, tectonic attributes and the relation to metallogene. In this paper, the author will systemically research the geochronology, petrologic and geochemical characteristics, tectonic setting of the magmatites and the relation to the metallogene in order to make metallogenic prognosis and to guide prospecting.The magmatites of Qianjin area distribute widely, most of them are intermediate-acid rocks, we also can see a few of basic veins.
　　The main rock types include granite, granite-porphyry, granodiorite, adamellite, alkali-feldspar granite, etc. According to geochemical characteristics, the magmatites of the study area have wide range of SiO2 contents(48.98%~81.12%), Na2O+K2O ranges from 3.89% to 9.87 % ,Al2O3 ranges from 8.67% to 18.32%, MgO ranges from 0.12% to 7.86%,the invariable elements have rich in aluminums and alkali, deplete in Mg and Fe, and low in Na2O compare with K2O. In the discrimination diagrams, the magmatites have characteristics either S-type or I-type granite. During Harker diagrams of oxides both assemblages show obvious evolutionary tendency, which may reflect they belong to comagmatic evolutionary series. Observing from rare earth elements and trace elements components, we can they display similar characteristics of riching in LREE and LILE, depleting in HFSE and HREE, and have obvious Eu anomaly, which draw the same conclusion that the magmatites originate from the same magmatic source in the aim of Xiling east mountain, Qianjin east mountain and Xiling south mountain.On the basis of field geological investigation to Xiling east mountain, Qianjin east http://www.chinamagnets.biz/ mountain and Xiling south mountain three deposits and reliable high precise isotopic dating, we confirmed the existence of tectonic-magmatic activity around Mesozoic epoch: the tuff of Qianjin east mountain granite-porphyry zircon U-Pb isotopic age is 201.7±1.2Ma and rhyolite zircon U-Pb isotopic age is 200.3±1.3Ma, Xiling south mountain granite-porphyry isotopic age is 195±3.0Ma. Combining to regional geology and isotope characteristic, the author consider that the magmatites of study area originate from intermediate-acid magma which through different degree fractional or crystallizayion ,formed by basic magma underplating lead to lower crust partial melting in the extension background, which are formed from extension environment after pale-Asia stured.
　　Tectonic-magmatic activities in Mesozoic period provide wide space and source. Analyzed results of metallogenic element, the author consider that granite-porphyry, alkali-feldspar granite and hybrid granite have important controlling effect to Pb, Zn, Cu polymetallic ore deposits, which are important resources of metallogenic elements. Xiaojingou group and Fengshantun group stratums also provide amount of metallogenic substances. Xiling east mountain and Xiling south mountain lead-zinc polymetallic ore deposits in the study area are belong to magmatic hydrothermal deposit and volcanic hydrothermal deposit, orebodies occurred in stratums or magmatites; Qianjin east mountain ferrum-copper-lead-zinc polymetallic ore deposit is belong to skarn deposit, ore body occurred in the contact zone of stratum and magmatite. Magmatic activity supply necessary metallogenic element and heat source. The deposits are formed in similar redoxmorphic environment. The formative process is that the melting fluid riching in metallogenic element ascending along the fault, then leaching or metasomatic country rock which leading to metallogenic element enrichment, Metallogenic fluid is locating and precipitating in the advantage place, consequently, forming hydrothermal or skarn deposit.Ore bearing rock bodies developed silications and skarnizations intensively, the geochemistry characteristics showed high in silic and Ball Neodymium Magnets potassium, low in magnesium and iron in invariable elements, and rich in LREE, deplete in Tb, Tm, no or weak Eu anomaly in rare earth elements and high in concentration coefficients of As, Sb, rich in Ba, Rb etc LILE, deplete in Nb, Ta, Ti etc HSFE in trace elements. So we can definite prospecting sign, in other means, tectonic convergence of NE and NW; the place developed in Xiaojingou group and Fengshantun group stratums and the place developed in magmatites which have character above mentioned, can regard as prognostic area and promote exploration arrangement for prospecting.

The Study of Sustainable Development in Baiyun’ Ebo Iron Mine

The Study of Sustainable Development in Baiyun’ Ebo Iron Mine
　　Baiyun’ Ebo iron mine, which mainly consist of Fe, rare earth、Th、Nb、is an intergrowth mine with many element. Iron should be exploited as main element according to purpose. With the development of science technology and economy, rare earth、·Th、Nb in has more exploitation value. In 2005, 15 academicians including Xuguangxian、Shichangxu made an united suggestion which increase the output of the West mine, decrease the output of the Main mine & the East mine and at last close them, to the State Council. The suggestion was introduced at the viewpoint of the Ball Neodymium Magnets long-term advantage of country and district, but the raw material of Baotou Iron which supports the development of Baotou and Inner Mongolian Autonomous, is mainly rooted in Baiyun’ Ebo iron mine,. it will influence the development of Baotou city and Inner Mongolian Autonomous Region. if the exploitation amount was decreased.There are many environment pollution, exploitation without empower in Baiyun’ Ebo. We should study the experience of other mine enterprises http://www.chinamagnets.biz/ and cities, change development mode, set up a long-term programming, develop circular economy, improve quality of workers and staff members, try for the policy and bankroll support of State, if we want to achieve rational utilization and exploitation in Baiyun’ Ebo iron mine,and protect environment, At last, achieve the coordination development of Baotou Iron & Steel (Group)Co, Ltd, and other affiliated factory and the economic and society of Inner Mongolia autonomous region.

纳米晶合金磁粉感应式真空连续带铸设备控制系统的研制

纳米晶合金磁粉感应式真空连续带铸设备控制系统的研制
　　Inductive vacuum continuous strip casting device (hereinafter shortformed continued rapid solidification) is a high performance equipment to produce magnetic nanocrystalline powder of rare earth alloys (hereinafter shortformed high performance powder). The system adopts the techniques such as continued yielding, induction melting, ceramic filter filting, nozzle jetting,strip casting and rapid solidifying. Development of such devices is of high importance to the large scale production of high-stabilization, high-consistency magnetic powder.Highly automatic powder manufacturing equipment can satisfy the special technological requirements of powder production, realizing Cylinder neodymium magnet effective control of the content of minim element, crystallization temperature, surface structure, little oxygenation, uniformity and consistency of powder, ensuring the production of high-consistency high-performance magnetic powder.Nanocrystallin powder of rare earth alloys is advantageous at magnetic speciality, reliability and stability.
　　It is widely applied in economical and military applications. Because the advanced equipment is the basis for production of high performance powder, many countries compitete intensively in this area. GE Co.,Ltd (USA) lead on this field. At present, research in this area becomes the hotspot.This thesis describes the control system design of continued rapid solidification based on induction in vacuum system. Based on the study of the relationships among different subsystems, the thesis analyzed and summarized the functionalities and characteristics of the subsystems: http://www.chinamagnets.biz/   intermediate frequency induction alloys melting system, constant temperature tundish system, high frequency induction nozzle system, rapid solidification wheel variable frequency device VFD system, vacuum acquirement system,oxygen analsys system and cooling system. The control models of each subsystem are designed and the associated control system is built. The system HMI(Human/ Machine Interface), the system program and the electric control circuit are designed and implemented based on MCGS(Monitor and Control Generated System) , SIEMENS S7-300 PLC and DDC(Direct Digital Control).

低压ZnO压敏陶瓷的制备及性能研究

低压ZnO压敏陶瓷的制备及性能研究
　　The influences of doping and processing on the character of microstruture and electrical properties were studied by the numbers. Through the studying, we find the suitable composition of Low-voltage ZnO varistor is:0.98ZnO + αPbO+βTiO2+ γB2O3+ x Cr2O3+ y Co2O3+ z MnO2+ a Fe2O3 + b SiO2+ c Sb2O3 , the parameters as following: α =0.05, β =0.005, γ=0.02, x=0.02, y =0.005, z =0.0025, a =0.002, =0.002 5, c=0.005. The good char-acteristic with V1mA< 14.5, α > 26 could be got at the proper firing temperature.The influence of nano ZnO and Rare-earths magnet lifter oxide were used as additives on the electrical properties and microstructure of Low-voltage ZnO varistor were systems studied. The results show that the properly adding nano ZnO can improve grain growth, decrease the varisteor voltage remarkably, and at the same time improves the Nonlinear property. The good characteristic with V1mA<14. 5, α> 26。
　　Doping Rare-earths oxide can reduce the size of ZnO grain evidently. Improve the varistor voltage and the Nonlinear, decreases the leakage current.In order to get better varistor, we built the model of Gradient Low-voltage ZnO varistor. In this paper, the http://www.999magnet.com/ electronic structure was calculated in the Co、 Cr、Mn、Ti、B、Pb, in doping of ZnO, the structure change, band structure density of state and the difference charge density were studied. It was performed by adoping the first-principles calculation of plane wave ultra-soft pseudo-potential technology of based upon the density founction theory.

Study on Ba0.7Sr0.3TiO3 Series Capacitor Ceramics with High Dielectric Constant and Low Temperature Changing Rate of Relative Permittivity

Study on Ba0.7Sr0.3TiO3 Series Capacitor Ceramics with High Dielectric Constant and Low Temperature Changing Rate of Relative Permittivity
　　In this article the barium-strontium titante preparation techniques in recent yearshave been summarized. The results of rare-earth oxide(such as Dy2O3、CeO2、La2O3、Y2O3 and Yb2O3 etc.), and the additions of MgO、Bi4Ti3O12 and Bi2Sn2O7 on dielectricproperties and microstructure are studied. The results show that the samples with highdensity, low pore rate and close homogeneous grain possess the high electric breakdownstrength and suited for X7R character. The Block neodymium magnet influences of technological parameter on theceramic properties have been investigated. Moreover, with the aids of SEM and XRD,the samples are analysed, and the results are used to discuss the machanism ofimproving characteristics.The following experiment results have been achieved:In barium-strontium titanate based ceramic, doping small rare earth oxide Dy2O3and Y2O3 can keep back the growth of crystal grain, producing close grain effect,making curie summit in entire work temperature range scatter and spread, get higherdielectric constant and good capacity temperature property, raising the compressionstrength of barium-strontium titanate based ceramic substantially.
　　When the content ofY in barium-strontium titanate ceramics is O.6wt% sintering at 1250℃, relativedielectric constant is more than 4000; from-25 up to 80℃, the change of temperaturedependence of relative permittivity is less than 20%; electric breakdown strength E ismore than 6kV/mm.In barium-strontium titanate based ceramic, doping small rare earth oxide CeO2and La2O3 can inhibit the grain growth and reduce the size of grain, and the dielectricperprities of barium-strontium titanate ceramics can be improved by adding properamount of La3+ and Ce4+ dopants. But replacement mechanism of Ce4+ and La3+ forbarium-strontium titanate is different. Dielectric perproties of Ce-doped BST ceramicsis better than that of La-doped. When the content of Ce4+ in barium-strontium titanateceramics is O.9wt% sintering at 1250℃, relative dielectric constant is more than 3000;from-25 up to 80℃, the change of temperature dependence of relative permittivity isless than 35%; electric breakdown strength E is more than 4kV/mm.X-ray diffraction analysis shows that the crystal structure of barium- http://www.chinamagnets.biz/  strontiumtitanate ceramics is not affected by Yb-doping. With the increase of sinteringtemperature, the dielectric constants of barium-strontium titanate ceramics becomeelevation.
　　When the content of Yb3+ in barium-strontium titanate ceramics is 0.9wt% sintering at 1250℃, relative dielectric constant is more than 10000; electric breakdownstrength E is more than 7kV/mm.The temperature dependence of dielectric constant is depressed and broadens withMgO doped. And XRD paterns show a single perovskite phase on samples. When thecontent of Mg2+ in barium-strontium titanate ceramics is 0.2wt% sintering at 1250℃,relative dielectric constant is more than 4500; from-25 up to 80℃, the change oftemperature dependence of relative permittivity is less than 25%; electric breakdownstrength E is more than 6.5kV/mm.The results show that Bi4Ti3O12 and Bi2Sn2O7 parcel crystal grain and are filledwith between grains, forming the complex and not even structure of ceramic body.Different phases restricts barium-strontium titanate ferroelectric phases, making thedepth of potential well of B position cation change shallow. In the broad temperaturescope, polarization is easily located by electric field, which showε-T characteristiccurve rather smooth. When the content of Bi2Sn2O7 in barium-strontium titanateceramics is 30wt% sintering at 1150℃, relative dielectric constant is more than 1500;from-55 up to 125℃, the change of temperature dependence of relative permittivity isless than 15%. Block neodymium magnet The results of Ba/Sr ratio on dielectric properties and microstructure are studied.The results show the optimized matching of Ba/Sr ratio is very important to dielectricperproties of BST ceramics.A kind of perfect ceramic material for capacitors is obtained by the selections ofdopants and processing. Its main electrical performances are:ε≥3500; tgδ≤0.01; from-25 up to 80℃, the change of temperature dependence of relative permittivity is lessthan 15%; electric breakdown strength E is more than 5.5kV/mm.

Synthesis and Modification of Ti-based Photocatalyst Materials and Study on the Photocatalytic Performance for Water Splitting into Hydrogen

Synthesis and Modification of Ti-based Photocatalyst Materials and Study on the Photocatalytic Performance for Water Splitting into Hydrogen
　　Energy sources are materials or movements providing energy for human.They are the foundation for human activity and development of human society.Compared with traditional fossil fuels,such as coal and oil,bring destruction on the environment; Hydrogen is an alternative energy source with high efficiency and pollution free. Hydrogen can be produced from clean and renewable energy sources,and thus its life cycle is clean and renewable.The photocatalytic water-splitting into Ball Neodymium Magnets hydrogen using semiconductor is a potentially clean and renewable method which is of both theoretical and practical significance.Searching for highly reactive and functional photocatalyst is the key.TiO2 as a traditional photocatalyst and another photocatalyst with perovskite-layered structure have drawn more and more attention.
　　The paper reports synthesis and modification of Sr3Ti2O7 and TiO2 semiconductor.The detailed contents are as follows:(1) Sr3Ti2O7 photocatalyst with perovskite-layered structure was synthesized by polymerized complex method(PCM).Cu ion as an effective dopant was loaded onto Sr3Ti2O7 catalyst,ωCu/Sr3Ti2O7 catalyst was applied in the mixture of water and methanol,methanol was used as a sacrificial agent under ultra-violet irradiation,and the catalyst was characterized by XPS,XRD,and UV-Vis DRS.The results showed that Cu ion existed in several kinds of valence and the photocatalytic activity of Cu/ Sr3Ti2O7 was superior to that of pure Sr3Ti2O7.Cu+ and adsorption oxygen can accelerate the interfacial electron transfer.When the amount of Cu ion was 1.5%(w), the best catalytic effect was obtained and the stable average hydrogen evolution rate was about 550-600μmol·h-1.TheωCu/Sr3Ti2O7 after reduction attained the highest hydrogen evolution rate that was close to 1140.8μmol·h-1.The value was seven times of NiO/Sr3Ti2O7 reported before.The paper http://www.chinamagnets.biz/ reported that synthesis method of Sr3Ti2O7 with perovskite-layered structure loaded with transition metal ion(Cu,Ag ion) with several valences.The optimal loading of Cu ion could enhance the photocatalytic activity greatly and that was explained by the mechanism that of loading Cu ion like such several valences can help semiconductor transferring charge and reaction.
　　The content of Cu+ and adsorption oxygen in photocatalyst tested by XPS characterization could testify the explanation.In addition,loading of the same main group Ag ion has been investigated. At the optimal loading of Cu ion,hydrogen production rate was enhanced as much as 35.5 times higher than loading of Ag ion.(2) Mesoporous TiO2 nanocrystals with anatase phase and high specific surface area was synthesized by sol-gel process using nonionic surfactant EO20PO70EO20 as a structure-directing agent,C16H36Ti as Ti precursor,La2O3 as catalyst support and ethanol as an extraction agent.Then removed template in moderate condition that was washing by reagent.The results indicated that the amount of doped La2O3 greatly effected on the formation of TiO2 with anatase phase,and the optimal content of doped La2O3 was 0.1%(mole fraction).The characterizations of XRD,BET,IR and HRTEM showed that an ordered mesostructure of TiO2 with narrow pore size distribution and large surface area(～367.7 m2·g-1) was obtained under the synthesis conditions.In the paper, http://www.chinamagnets.biz/    Mesoporous TiO2 doped with rare earth was synthesized.The intensity of TiO2 inorganic framework and the stability of the mesoporous structure were stronger than non-La2O3 doped.When the template was washed by boiling ethanol,anatase phase was formed.It indicated that doping La2O3 could accelerate the formation of anatase phase.Study on rare earth how to affect structure,crystal and photocatalytic activity.Both of two experiments have indicated the optimal loading of Cu or doping of La2O3 clearly.

Exploration on Crystallization Habit and Optical Property of BaY2F8

Exploration on Crystallization Habit and Optical Property of BaY2F8
　　Since the crystal BaY2F8,which is easy to be doped with rare earth elements,has many merits such as good transparent property, wider penetrating rang(0.125–15μm) and lower phonon energy, comparing with other host crystals it has been demonstrated to be suitable for up–conversion laser. On the other hand, being the trivalent rare earth element, Erbium (Er3+) which not only has rich energy levels, but also has other good characteristics, such as narrower luminescent band, higher capacity of absorption, higher efficiency of conversion and stable physical and chemical property, is being utilized and investigated as the active ion for laser materials both at home and abroad. In this thesis, Ball Neodymium Magnets researches mainly focus on the growth parameters of BaY2F8 and Er3+:BaY2F8 under TGT method, growth unit of BaY2F8.
　　And the spectrum parameters of Er3+:BaY2F8 is also calculated.Based on the theoretical model of anionic coordination polyhedron growth unites and analyzed the crystal structure of BaY2F8, this paper studied crystallization habit of BaY2F8 from the spontaneous cooling. And presented the growth unites of BaY2F8 are eight--fold dodecahedral polyhedron with Ba2+ center and eight--fold dodecahedral polyhedron with Y3+ center. Two kinds polyhedrons’ superposition formed BaY2F8 crystal. Using its XRD, making clear why {200}、{130}、{021}、{330}、http://www.chinamagnets.biz/ {-111}、{111}、{221} and {002} faces are more growth. These things support with proof of applicability to the BaY2F8 crystal growth by anionic coordination polyhedron, and indicate a new growth method of BaY2F8 crystal in theory.The absorption spectrum was also measured and the several characteristic absorption peaks of Er3+ ions are clear. Using the J-O theory, the three phenomenological intensity parametersΩi ( i =2,4,6) were fitted, which were 1.43×10-20cm2, 0.49×10-20cm2 and 1.36×10-20cm2 respectively. The fluorescence decay times of Er:BaY2F8 crystal were analysed. The decay time of 4I11/2 state is about 5 ms in Er:BaY2F8 crystal, which is quite longer than in oxide.

In Vitro Three Categories as Candidate Microbicides Against HIV-1IIIB Activities and Antiviral Mechanism

In Vitro Three Categories as Candidate Microbicides Against HIV-1IIIB Activities and Antiviral Mechanism
　　AIDS is the most serious disease for human health.During the struggle against AIDS,people revealed out the pathogen of AIDS,developed many antiviral drugs,which reduced the incidence of AIDS and mortality rate,but AIDS is not cured yet.At present,sexual transmission plays a major role in the spread of HIV in the world.More than 90%of new HIV infections are spreading through unprotected intercourse in whole world.The relentlessness of the HIV/AIDS neodymium magnets epidemic and its growing feminization have prompted people to acknowledge the urgency to develop new prevention technologies. Microbicides are now recognized as among the most promising prevention technologies on the horizon.To develop a microbicide used under women control has been recognized as an important method as vaccine of HIV to control transmission of HIV-1.There has been significant progress in microbicide research and development in the past 15 years.Over 30 compounds or formulations are undergoing preclinical or clinical studies.
　　However,the number of potential products is not large enough.Discovery of novel compounds for use as potential microbicide candidates is a long-term task.In this paper,we focused on the developing novel microbicides from traditional Chinese medicine,lectins and rare earth elements.The IC50values of sulfated polysaccharide D2,D3,D6,D8,D9 were (10.28±1.12)μg/ml,(10.90±1.08)μg/ml,(8.72±1.08)μg/ml,(15.10±1.08)μg/ml, (11.10±1.09)μg/ml,and the SI values were 261,331,313,213,203, respectively.The rare earth element CCYCN had anti-HIV-1ⅢBactivity,its IC50value was(4.02±1.07)μg/ml,and its selective index(SI)value was 229. The unsulfated polysaccharide compounds DN,DN1,DN2,which were obtained by different methods,also could inhibit HIV-1ⅢBactivity,their IC50values were(33.12±1.08)μg/ml,(27.19±1.08)μg/ml,(10.68±1.08)μg/ml, their http://www.chinamagnets.biz/ selective indexs(SIs)values were 22,28,87,respectively.According to anti-HIV-1ⅢBactivity experiment,we knew the sulfated polysaccharide compounds D2,D3,D6,D8,D9 had better anti-HIV-1ⅢB activities than other compounds.In order to know the antiviral mechanisms of the compounds D2,D3,D6,D8,D9,time-addition assay,fusion and different pre-treatments were used.The results showed that the sulfated polysaccharide D2,D3,D6,D8,D9 may affect the early stage of HIV life cycle.We also studied on the stabilities of the sulfated polysaccharide compounds D3 and D6.SPSS15.0 was used to analyze data we acquired,the results showed the IC50values of D3 and D6 had the notable relation of linearity.In a word,the sulfated polysaccharide compounds D3 and D6 demonstrated strong anti-HIV-1ⅢBactivities,and may be potential candidates for microbicides development.They shoud be further studied on antiviral mechanism and stability in the future.

Investigation on Magnetocaloric Properties of Gd1-xMx(M=V、Ti) and Gd0.97-yDyyV0.03 Alloys

Investigation on Magnetocaloric Properties of Gd1-xMx(M=V、Ti) and Gd0.97-yDyyV0.03 Alloys
　　Recently, Gadolinium metal has been the most thoroughly studied material for its MCE, but the price of Gd is very expensive, the curie temperature of Gd is fixed, as a result, its working region is quite narrow. Considering the various requirements for practical application, it is necessary to search for some magnetic refrigerants which MCE properties are same as(or higher than) Gd with different Curie temperatures (Tc), In this thesis, we investigated the binary and ternary Gd-based solid solution alloys by adding nonferrous metal elements(V、Ti), and heavy rare-earth element (Dy) to estimate china magnets their magnetocaloric properties.The author of this paper researched on the phase structure, the curie temperature, adiabatic temperature changes and magnetic entropy changes of Gd1-xMx(M=V、Ti) alloys and Gd0.97-yDyyV0.03(y=0.1,0.2,0.3) alloys that were prepared by arc melting in an argon atmosphere.X-ray diffraction patterns show that all Gd1-xMx(M=V、Ti) alloys retain the phase structure of pure Gd. Compared with the pure Gd, the Curie temperature of these alloys decrease slightly. The adiabatic temperatures changes(ΔTad)of these alloys at Curie points increase firstly and decrease latter with increasing x in a field change 0～1.4T.
　　The adiabatic temperatures changes of Gd1-xTix alloys is, when x=0.09, 102.4% of that of Gd. The adiabatic temperatures changes of Gd1-xVxalloys is, when x=0.03, 106% of that of Gd; The magnetic phase transitions from paramagnetic state to the magnetically ordered state in Gd1-xVx alloys are the second order type. The magnetic entropy changes of Gd1-xVx alloys at Curie points increase firstly and decrease latter with increasing x in a field change 0～2T, the china magnets best magnetic entropy changes of Gd1-xVx alloys at Curie points increase is 5.19J/kg.K, when x=0.03, 103.8% of that of Gd; furthermore, the refrigeration capacities are larger than Gd.The ternary Gd0.97-yDyyV0.03(y=0. 1,0.2,0.3) alloys were made on the basis of above binary Gd-based solid solution. X-ray diffraction patterns show that these alloys are all the hexagonal lattice structure as same as Gd; Their curie temperatures can be tuneable with an experiential formula, Tc=291.38-104.9y. The adiabatic temperatures changes(ΔTad)of these alloys at Curie points decrease firstly and increase latter with increasing y in a field change 0～1.4T.
　　The best adiabatic temperatures change of Gd0.97-yDyyV0.03 alloys is 2.65K when y=0.1, 106.85% of that of Gd; The magnetic entropy changes of Gd0.97-yDyyV0.03 alloys at curie points increase firstly and decrease latter with increasing y in a field change 0～2T. When y=0.1, the magnetic entropy changeΔSM is 99.2% of Gd, cooling capacity q is 104.6% of china magnets Gd; when y=0.2,ΔSM is 106.6% of Gd, q is 99.5% of Gd.Above works reveal that magnetocaloric properties of Gd0.91Ti0.09,Gd0.97V0.03, Gd0.87Dy0.1 V0.03,and Gd0.77Dy0.2V0.03 are the best in Gd1-xMx(M=V、Ti) alloys and Gd0.97-yDyyV0.03(y=0.1,0.2,0.3) alloys. These suggest that these alloys are promising candidates for magnetic refrigerants which may be used in the active magnetic regeneratior near room temperature in low magnetic fields.

Study on Technical Conditions for Preparing 2,6-diisopropyl Naphthalene from Refined Naphthalene

Study on Technical Conditions for Preparing 2,6-diisopropyl Naphthalene from Refined Naphthalene
　　2,6-Diisopropylnaphthalene (2,6-DIPN) is the precursor of 2,6-naphthalene dicarboxylic acid, which is an important monomer for synthesizing new polyester, poly (ethylene naphthalate), and thermotropic liquid crystalline polymers. In this study, the shape-selective isopropylation of naphthalene with propylene has been processed in 0.5L autoclave with steam-dealuminated mordenite (SDHM) as the catalyst to produce 2,6-DIPN instead of the conventional Friedel—Crafts catalyst.The neodymium magnets nitrogen content in refined naphthalene showed great impact on the activity of catalyst. Results showed that the lower the nitrogen content in refined naphthalene, the better the results of isopropylation. Hydroisopropylation could effectively slow down the deactivation rate of catalyst.
　　When the reaction conditions were at reaction temperature 275℃, hydrogen pressure 0.4MPa, reaction time 7h and 7% SDHM by mass, the average conversion rate of naphthalene could be maintained at approximate 90%, the average yield of target product, 2,6-DIPN,≮35 %, and selectivity close to 65% showing good practicability.When modified with rare earths, the acid sites on external surface of SDHM were partly covered, the selectivity in isopropylation of naphthalene could be improved. The selectivity of 2,6-DIPN, 2,6-/DIPN (%), and 2,6-/2,7-DIPN mol ratio could be significantly raised, and the yield of 2,6-DIPN increased, so that the product could be more easily separated and purified. The catalyst modified with mixed rare earths (La, Ce, and Pr) was better than that modified with single rare earth La in its reaction effectiveness; furthermore, after regeneration it could still http://www.chinamagnets.biz/ keep its good activity.A product of 2,6-DIPN with purity≥99% was produced through static fractional crystallization. By repeated crystallization of melts with different concentration levels, the yield of pure 2,6-DIPN was enhanced to 87%. It is significant in its applicability in manufacturing. The eutectic temperature and the composition of eutectic point of 2,6 DIPN～2,7-DIPN binary system were determined to plot corresponding solid liquid phase diagram, which could be taken as guidance in controlling crystallization temperature.The isomerization within DIPN molecules was not easy-to-occur, however, was subject to transalkylation with naphthalene to obtain a product rich in monoisopropylnaphthalene, which would be beneficial in utilization of by-products. The conversion rate of DIPN reached 77%. The amorphous silica-alumina LXC-11 was the suitable catalyst.

铈稀土吸附剂除磷脱氮实验研究

铈稀土吸附剂除磷脱氮实验研究
　　With the development of economy in recent years, the eutrophication problem of lakes and rivers has become increasingly serious all over the world. The main reason is that many nutrients inputting into the water body, such as nitrogen, phosphorus. So many documents make clear that phosphorus and nitrogen quantity are the key role, and the removal of nitrogen, phosphorus are so urgent to eutrophication of water body, such as lakes and reservoirs.The traditional methods of nitrogen and phosphorus removal are chemical and biological methods. However, biological treatment process is not steady for nitrogen and phosphorus removal because the pollutants are different in Special shape NdFeB magnets style, which result in operating badly, and at the same time temperature and pH value of influence play a great impact on removal ratio which relys on BOD in feed. When BOD: N: P is 100:5:1 can get a better treatment effect. To the chemical methods, which consume a large amount of medical flocculants and coagulating. Contemporarily a large amount of chemical sludge comes into being, and difficult to handle it. Adsorption which takes up the deficiency of biological and chemical measures, which is a high efficiency measure of removing nitrogen and phosphorus, and the technics is simple.The thesis research takes adsorption method to deal with nitrogen and phosphorus which lead to eutrophication of water body, for the purpose of the depth of wastewater for nitrogen and phosphorus removal to provide a practical new ways.
　　The results show that:(1) The appropriate conditions of rare earth adsorbent treated by microwave for nitrogen and phosphorus removal is for the amount of adsorbent 2g/L, and reaction time is 2.5 hours, and the pH value is between 4-6;(2) To La and Ce different proportion of Rare Earth adsorbent, there is not hardly difference in phosphorus removal, the efficiency gets better to nitrogen removal with the increaseing of Ce content;(3) Comparison between roasting-adsorbent and microwave-adsorbent in nitrogen and phosphorus removal, the result shows microwave synthesis method is better than the roasting method. For the phosphorus-containing 1mg/L, nitrogen-containing http://www.999magnet.com/ 15mg/L wastewater, the amount of adsorbent of 2g/L, phosphorus removal rate is more than 99% ,nitrogen removal rate reached more than 80 percent; the largest phosphorus adsorption capacity is 18.3 mg/g; nitrogen adsorption capacity of the largest 6.25 mg/g respectively;(4) On regeneration test, Appropriate regeneration liquid is NaOH concentration of 0.04mol/L, denitrification efficiency below 60% after 10 adsorbent regeneration, phosphorus removal efficiency below 80% after 15 adsorbent regeneration;(5) On adsorbent Molding, appropriate adsorbent molding pressure is 10 MPa, additives of NaHCO3 is 15% (mass ratio), and temperature of 900℃.when adsorbent dosage is 5g/L in dealing with wastewater , phosphorus removal rate reachex 61.7%,and nitrogen removal rate reachex 51.7%;(6) The guitar experiment shows that, the amount of adsorbent is 5g/L nitrogen and phosphorus removal efficiency can also reach 99% after 8 h.

Characteristics and Petrogenesis of the Jiangmiao and Gushan Intrusions in the Ningwu Basin, Eastern China

Characteristics and Petrogenesis of the Jiangmiao and Gushan Intrusions in the Ningwu Basin, Eastern China
　　In the Ningwu basin located in the Lower-Middle Valley of Yangtze River is exposed a suite of subalkaline to alkaline igneous rocks, of which the intrusive rocks are gabbro and pyroxene diorite, represented by the Jiangmiao and Gushan intrusions. A field geologic investigation combined with a petrographic, petro-geochemical and isotopic study has been Block Neodymium magnets carried out on these two intrusions. The general features of the intrusions have been ascertained through this study, which gives a clue to better understanding the background and process for the formation of these two intrusive bodies.The following are achievements obtained through the study in this thesis.1. The lithologies of the Jiangmiao intrusion are predominated by gabbro and diabase, with less diorite-porphyrite and diorite, while those of the Gushan intrusion by pyroxene diorite.2. The Major element, trace element and rare earth element analyses show that these two intrusions consist of subalkaline to alkaline basic to intermediate-basic rocks with close genetic relation.3. The rare earth http://www.999magnet.com/ element and isotope data support the formation of these two intrusions through slight crustal material contamination combined with little fractional crystallization of basaltic magma derived from upper mantle and derivation of basaltic magma in Jiangmiao from deeper part of the upper mantle.4 The Jiangmiao intrusion is dated at 127.2±1.9Ma using Rb-Sr isochron method and represents product generated in the initial stage of the Ningwu volcanic basin formation.

共沉淀法合成的Sr2CeO4及Sr2CeO4：RE(RE=Eu，Sm，Er，Gd)材料的发光特性

共沉淀法合成的Sr2CeO4及Sr2CeO4：RE(RE=Eu，Sm，Er，Gd)材料的发光特性
　　With the rapid developments of new technology, luminescent materials science and technology have attracted much attention. Today, luminescent materials play important roles in many fields of the society, and the cognition and research work on them have capacious academic value and practical application. The accession of rare earth elements brings the remarkable improvement to the luminescent materials, being a bout of revolution relative to the traditional luminescent materials. Thus the rare earth luminescent materials become the research focus more and more.Sr2CeO4 is a new and efficient blue emission powder phosphor, It can also be regarded as the host material besides giving Segment neodymium magnets out light itself. Co-precipitation has been used to prepare the precursor of Sr2CeO4 via different precipitants. However the fluorescent performances of Sr2CeO4 synthesized by different precipitants were not compared.In this paper, we prepared Sr2CeO4 and Sr2CeO4: RE (RE= Eu, Sm, Er, Gd) by co-precipitation.Here, the synthesis of Sr2CeO4 powders through chemical co-precipitation using ammonium oxalate or ammonium carbonate as precipitants was reported.
　　The optimum conditions to prepare Sr2CeO4 phosphor powder should use the carbonate precursor, and raise the heating temperature to 1250°C.Ce4+→Eu3+ energy transfer exists in Sr2CeO4: Eu3+. Under the excitation of UV light, with the increase of the Eu3+ concentration form low (1 mol%) to high (10 mol%), the emission light changes from blue-white to red-white. In addition, the energy transfer phenomenon of Gd3+→Eu3+ in Sr2CeO4: Eu3+,Gd3+ was observed. When the Gd3+ concentration is 3 mol%, the optimum Eu3+ luminescent effect in Sr2CeO4: Eu3+, Gd3+ is achieved.In the experiment of Sr2CeO4: Sm, we confirm the optimum heating temperature and the Sm3+ concentration. In spite of the sintering period only takes 3 h, the intensity of emission spectra is twice as that of which was synthesized by conventional high temperature solid state reaction and sintered for http://www.999magnet.com/ 30 h.All the time, Er3+ has been concerned abroad due to up-conversion emissions. Sr2CeO4: Er phosphor was prepared, and green up-conversion emissions (547 nm) and red up-conversion emissions (644 nm) was observed. When the Er3+ concentration is 2 mol%, the sample has the best effect of up-conversion emissions.The novel studies of the work are in the following:(1) We compared the fluorescent effect of Sr2CeO4 synthesized by different precipitants and confirmed the optimum condition of preparation.(2) Although the heat-treatment period was decreased greatly as compared with conventional solid state reaction, the luminescence efficiency was evidently improved. No doubt, they are suitable to the application of luminescent materials.