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1.
研究稀土氧化物制备过程中灼烧过程对最终稀土氧化物中氯的影响,考察了碳酸盐灼烧时的装填量与装填方式、灼烧温度、升温曲线等对最终稀土氧化物中氯的影响。结果表明,在碳酸盐非金属(氯离子含量)元素含量一定的条件下,碳酸盐的装料越少、升温速度越慢、灼烧温度越高,最终产出的稀土氧化物的氯含量就越低。  相似文献   

2.
Complex of rare earth with carboxylic acid was prepared by precipitation and direct method. It was copolymerized with such monomers as acrylic acid and other ones to synthesize ionomer of rare earth and organic polymer with different rare earth contents. Its glass-transition temperature and heat stability were analyzed by TG and DTA. Infra-red detector was used to show its structure. The effect of rare earth complex prepared by different methods on copolymerization and properties of copolymers was also discussed.  相似文献   

3.
Inrecentyearsnewmetallurgicaltech niquesforproducingrareearthsilicateal loys[1~ 3] havegreateffectonimprovingrareearthsilicatealloysindustry .Thecarbonther malreductiontechnology (namedas“onestepmethod”)canshortentheprocess,reducetheinvestment,increasetherec…  相似文献   

4.
Teapolysacchridecomplex ,oneofthebasicmacromoleculesintea ,hasmanyphar maceuticaleffectsandiseasytodissolveinteainfusion[1] .Zhongetal .[2 ] discoveredthatthereisaREbindingpolysaccharideinleavesofteaplant (CamelliaSinensisLO .Kuntze) .Inthispaper ,thestudyontheco…  相似文献   

5.
本文研究了稀土金属中氯根测定的不稳定原因 ,采用正交实验方法 ,建立了既经济又稳定的测定方法。同时探索了氟化稀土中氯根的测定  相似文献   

6.
稀土在钢中的作用及加入方法   总被引:5,自引:0,他引:5  
阐述了稀土金属作为变性剂在钢中的作用,其生成物及稀土金属的最佳加入量问题。总结了目前钢铁冶金工业生产中采用的加入稀土金属的几种方法,提出了当前钢中加入稀土研究的主要课题。  相似文献   

7.
Optical and magnetic properties of GaN epilayers implanted with ytterbium   总被引:1,自引:0,他引:1  
We have studied the optical and magnetic properties of ytterbium implanted GaN epilayer grown on(0001)sapphire by metalorganic chemical vapor by deposition(MOCVD).Samples were implanted at room temperature with Yb ions at dose 4x1015 cm-2 and energy of 150 keV.The implanted samples were annealed at 1000 ℃ in N2 at atmospheric pressure to recover implantation damages.The photoluminescence (PL),PL excitation(PLE),and PL kinetics have been studied with continuous and pulse photo-excitations in 360-1100 nm spectral range at different temperatures.The characteristic Yb3+ion emission spectra were observed in the spectral range between 970-1050 nm.Theoretical fittings of the experimental PL temperature and PL kinetics data suggest that Yb3+ions are involved in at least two major luminescence centers.The PLE spectra indicate that excitation of the Yb3+ion occurs via electron-hole pair generation and complex processes.Magnetization versus magnetic field curves shows an enhancement of magnetic order for Yb-implanted samples in 5 K to 300 K temperature range.The Yb-implanted GaN sample showing weak ferromagnetic behavior was compared with the ferromagnetic in situ doped GaYbN material.  相似文献   

8.
采用等离子光谱法测定碳酸稀土、氯化稀土中氧化铕含量,系统考察了不同试样浓度、不同基体配分下共存元素对测定元素的影响,并进行了加料回收及精密度实验,结果稳定可靠,与ICP-MS的对照结果令人满意。测定范围0.01%~0.30%。  相似文献   

9.
在分析国内外稀土市场情况的基础上,就如何充分发挥湖南稀土优势,摆脱困境,开发稀土产品提了六条意见。  相似文献   

10.
研究了氟碳铈矿晶体配 Si O2 球团 ,在 10 0 0℃、12 0 0℃温度条件下煅烧时稀土硅酸盐的生成情况。结果表明 ,稀土原料和 Si O2 直接造球 ,在 10 0 0℃温度条件下 ,就有稀土硅酸盐的生成。  相似文献   

11.
林建新  俞秀金 《稀土》2005,26(4):69-72
介绍了稀土在氨合成催化剂中的研究情况,重点综述了稀土的作用机理及催化性能,还介绍了国内稀土氨合成催化剂性能及工业应用情况。  相似文献   

12.
稀土企业社会责任对于解决稀土问题至关重要.文章设计并运用企业社会责任驱动模型对稀土企业社会责任驱动力进行分析.分析表明目前无论在利益还是伦理方面,稀土企业所受的社会责任驱动力都有极大可能被弱化或异化.要推动稀土企业社会责任的改善,并根本解决稀土问题,稀土企业、政府、社会的内在机制都必须有所完善,最终共同形成能够产生良性互动的系统.   相似文献   

13.
张林昌 《山东冶金》1995,17(5):52-54
山东省稀土工业的发展应立足本省资源优势,充分发挥科研,生产,开发应用等各方面的作用加强行业协作,走稳步发展之路,促进山东经济建设发展。  相似文献   

14.
Phase Analysis of Cemented Carbide WC—Co Boronised with Yttrium   总被引:1,自引:0,他引:1  
Phase analysis for the coated surface with B4Cand Y2O3of cemented carbide WC-20Co in vacuum-heating was carried out by high-temperature X-ray diffraction from ambient temperature to 1300℃,The results show that,the high-concentration active boron atoms are released from the boron-supply agent B4Clocated on the alloy surface and diffused into the γphase,leading to forming the three-element boron-bearing compound W2Co21B6beside forming boron-bearins compounds on the blank surface.By contrast with boronising only,the element yttrium in boronization broadens the boronising temperature range during vacuum-sistering,catalyzes the decarbonisation decomposition of B4C and promotes diffusion of active boron atoms into the bulk of WC-Co.  相似文献   

15.
稀土新材料及其在高技术领域的应用   总被引:49,自引:5,他引:44  
陈占恒 《稀土》2000,21(1):53-57
本文简要叙述了稀土新材料及其在高技术领域的应用,并进行了简要分析,认为提高我国稀土产业自身高技术应用水平以及开发稀土新材料及其在高技术领域应用技术是实现稀土资源优势向经济优势转化的根本出路。  相似文献   

16.
The application of rare earths(RE) in the Ni saving heat resistant steel was studied by metalloscopy,scanning electron microscopy(SEM),energy dispersive spectrometer(EDS),X-ray difference(XRD).Because the diffusion of chromium was promoted by RE,a dense and adhesive Cr2O3 layer could form rapidly at the early oxidation stage,which played a effective protection role;the pinning effect of silicon dioxide was enhanced by RE in the internal oxidation layer,which had a block effect on the diffusion of metal ions and oxygen ions at later stage of oxidation and resulted in that the high temperature oxidation rate of RE heat resistant steel was decreased.  相似文献   

17.
Preparing process was presented and the influences of concentration of acetic acid, reaction temperature, the ratio of cerium carbonate and acetic acid, heat preservation time to the yield of cerium acetate were discussed.The crystalline cerium acetate and rare earth acetate such as ( La, Ce, Pr, Nd) (Ac) 3, ( Ce, Pr, Nd) (Ac) 3, ( Pr, Nd, Er,Y) (Ac) 3 and yttrium acetate were prepared under this condition.The shape, structure and composition of the crystals were determined by the methods of SEM, TG-DTA, X-ray diffraction and chemical analysis.The optimum prepared conditions of cerium acetate were described.This prepared process has characteristics such as simple process route, low cost, high yield, good quality, no pollution to environment, etc.  相似文献   

18.
林楠  何金桂  李勇 《有色矿冶》2012,28(3):18-20,7
以含稀土铁尾矿的资源回收与利用为对象,综述了含稀土铁尾矿中稀土、铌的回收工艺。研究表明:MgO固氟-NH4Cl焙烧法提取稀土,可使稀土回收率达85%以上,是一种绿色的稀土提取工艺;碱金属亚熔盐液相法回收尾矿中铌的工艺使难处理铌矿的分解率和回收率都在95%以上,具有广阔的应用前景;同时也综述了二氧化钛、锌的回收工艺。  相似文献   

19.
为实现无铵富集稀土,以复合钠盐为沉淀剂,对铝盐体系离子型稀土矿浸出液中稀土进行富集。考察了pH对稀土浸出液除铝效果的影响,研究了不同沉淀剂、沉淀剂配比及用量、终点pH、反应温度、反应时间、陈化时间对稀土沉淀率的影响。结果表明,在初始稀土浓度0.014 64 mol/L、铝浓度0.54 g/L、初始pH=3.89、反应温度25 ℃、反应时间60 min的条件下,除铝终点pH=4.93时,残余铝浓度为13.02 mg/L,稀土损失为1.2%;当复合沉淀剂用量为0.7倍理论量的70%NaHCO3+30%Na2CO3、沉淀终点pH=6.72、反应时间60 min、反应温度25 ℃、陈化时间40 min时,稀土沉淀率高达99.68%,灼烧后氧化稀土总量为96.48%,铝含量为0.52%。  相似文献   

20.
稀土高分子聚合物及其应用   总被引:16,自引:0,他引:16  
稀土高分子是一类具有许多优异性质和很大应用价值的功能材料,其开发和应用前景十分迷人。本文就掺杂型和键合型稀土高分子的国内外研究概况以及它们在光、电、磁、催化、分析等领域的应用做详细的论述。  相似文献   

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