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Separation and purification of Yb_(2)O_(3) by ion exchange chromatography and preparation of ultra-high purity Yb_(2)O_(3)

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Rare Metals 2023年第8期42卷 2725-2735页

作者： Xi-Juan Pan Zhi-Qing Yang Yang Xu Meng Wang Xiao-Wei Huang Zong-Yu Feng Qiang Zhong Xin-Lin Peng National Engineering research Center for Rare Earth China GRINM Group Co.Ltd.Beijing 100088China GRIREM HI-TECH Co. Ltd.Langfang 065201China GRIREM Advanced Materials Co. Ltd.Beijing 100088China General research Institute for Nonferrous Metals Beijing 100088China

Ultra-high purity Yb_(2)O_(3) is the critical material of many high-tech materials such as laser glass and fiber,in which impurities seriously affect the laser color quality,intensity and *** order to reduce the influence of impurities on the properties of laser materials,the purification process of Yb_(2)O_(3) was studied by comparing two kinds of resins(RT-1 and RS-1)using improved ion-exchange chromatography(IEC)*** this study,through the synergistic improvement of resin structure and eluting system,the environmental pollution caused by ammonia water in the traditional IEC method was reduced,and the requirements of high temperature and pressure were *** ion exchange behavior and impurity removal mechanism in the resin column during the loading and eluting process were compared and *** experimental results show that RS-1 resin is all superior to RT-1resin in elements selectivity,ion exchange capacity and impurities removal *** separation and purification by IEC with RS-1 resin,the total removal rate of rare earth impurities was 77.59%and that of non-rare earth impurities was 95.86%when Yb recovery was more than 70%,both higher than that of RT-1 resin(73.26%and 83.18%).This indicates that the improved IEC method is very effective in separating and removing different metal impurities from Yb_(2)O_(3).The pilot test results of IEC method separating and purifying Yb_(2)O_(3) with RS-1 resin show that the purity of Yb_(2)O_(3) can be increased from 99.9929%to 99.9997%by IEC *** has exhibited huge potential of preparing ultra-high purity Yb_(2)O_(3),especially the deep removal of non-rare earth impurities.

关键词： Ultra-high purity Yb_(2)O_(3) Ion exchange chromatography(IEC) Laser fiber Separation mechanism Impurities

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Tungsten separation behavior on preparation of high-purity cerium by combined vacuum gravity sedimentation-directional solidification

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Journal of Rare Earths 2024年第6期42卷 1182-1186,I0007页

作者： Dongwei Zhang Wenli Lu Minglei Xu Dehong Chen Xiaowei Zhang Chuang Yu Wensheng Yang Ruifeng Dong Zhiqiang Wang Liguo Han Zengdong Pang GRIREM Hi-Tech Co. Ltd.Langfang065201China National Engineering research Center for Rare Earth China GRINM Group Co.Ltd.Beijing100088China GRIREM Advanced Materials Co. Ltd.Beijing100088China

In light of the difficult removal of harmful impurity tungsten(W)in Ce metal,in this paper a combined vacuum gravity sedimentation-directional solidification method was innovatively designed and the W separation behavior was *** reducing the electron beam power instantly and gradually at reduction rates of 1,3 and 5 kW/min,it is found that W is enriched at the bottom of ingots as the melt *** enrichment effect is much better than that of single purification method and the enrichment degree increases as the beam reduction rate decreases,attributed to the k0(W)>1 andρ(W)>ρ(Ce).Overall,the minimum content of W impurity can decrease from 630 to 0.1 ppm at the top of the ingot,and the purity of Ce increases from 99.932 wt%to 99.995 wt%by this combined ***,this paper provides a new method for the removal of high density and low evaporation coefficient impurities in low vapor pressure rare earth metals.

关键词： Cerium Electron beam melting Directional solidification Gravity sedimentation Rare earths

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Effect of heat treatment on the microstructure and properties of CVD SiC fiber

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Journal of Materials Science & Technology 2017年第11期33卷 1378-1385页

作者： Chuanbao Zhao Yumin Wang Guoxing Zhang Qing Yang Xu Zhang Li'na Yang Rui Yang Institute of Metal research Chinese Academy of Sciences Beijing Branch Huawei Technologies Co. Ltd.

In this study, the effect of heat treatment on the room temperature strength of W-core Si C fiber produced by chemical vapor deposition（CVD） was investigated. Thermal exposure in the temperature range of 900–1000？C decreases the strength of the Si C fiber. Fracture morphology analysis indicates that failure initiations predominantly take place at the W-core/Si C interface. A reaction layer that formed at the W-core/Si C interface during thermal exposure degraded the fiber strength and an empirical linear relationship of strength vs thickness of the reaction layer can be obtained. The kinetics of the growth of the W-core/Si C reaction layer were determined.

关键词： Silicon carbide fiber Heat treatment Reaction layer Strength degradation

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Development Strategy and Countermeasures of China's CBM Industry under the Goal of “Carbon Peak and Neutrality”

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Journal of Earth Science 2023年第4期34卷 975-984页

作者： Fengyin Xu Xia Yan Fenglin Wang Xinyuan Ma Jian Yun Hongna Wang Borui Xu Shuangyuan Zhang Delei Mao China United Coalbed Methane National Engineering research Center Co. Ltd.Beijing 100095China research Institute of Petroleum Exploration&Development PetroChina Coalbed Methane Co.Ltd.Beijing 100028China research management department CNPC Research Institute of Safety and Environment Technology Co.Ltd.Beijing 102249China Exploration technical R&D Center CNPC Exploration Software Co.Ltd.Beijing 100080China

China’s coalbed methane(CBM) industry is in an extremely important “climbing period” and “strategic opportunity period”,which can be generally characterized by “three low and one small”:low degree of exploration and development,low adaptability of main technology,low return on investment and small development *** the “carbon peak and neutrality” background,the development status of CBM industry is systematically *** resources,technology,management problems and reasons are *** and countermeasures to accelerate the industrial development are put forward according to the factors such as efficient development of resources,major technical breakthrough,talent team training,policy formulation and implementation,return on investment and so *** existing problems are as follows:(a) The overall occurrence conditions in China are complicated and the development is difficult compared with the other countries.(b) The research precision accuracy of CBM resource conditions is not enough.(c) The adaptability of technology is poor.(d) The management mode is not *** view of these problems,this paper puts forward the “two steps” development strategy and the technical and management countermeasures of “five in one”.The corresponding “five in one” technology and management countermeasures are the formulation and implementation of relevant safeguard measures in accordance with the principle of collaborative innovation in five aspects:resources,technology,talents,policies and *** the above measures,the dream and grand blueprint of CBM industry shall be realized.

关键词： coalbed methane CBM industry carbon peak carbon neutrality development strate-gy countermeasures.

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Measuring powder flowability with a modified Warren Spring cohesion tester

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Particuology 2011年第2期9卷 148-154页

作者： Salam A.Mohammed Ezzat C.Abdullah Derek Geldart Abdul Aziz A.Raman Department of Chemical Engineering Faculty of EngineeringUniversity of Malaya Powder research ltd. Harrogate& University of Leeds

The measurement of powder flowability is a major concern for most industrial processes that deal with the handling of bulk solids as raw materials, intermediates, or products. The development of devices that measure the flowability of non-aerated powders has not progressed as rapidly as might have been hoped since most research activities have been based on various types of shear testers intended to aid the design of hoppers. A new flowability indicator named as weighted cohesion （WS） is established using newly improved version of direct cohesion texture. A cornerstone of the proposed technique is that the procedure is automated, using a digital Warren Spring tester called Warren Spring-University of Malaya cohesion tester （WSUMCT）, thus making results operator-insensitive. Besides being a practical tool to diagnose the cohesion of experimental powders, the ratio between measured cohesion （using WSUMCT） and aerated density （using Hosokawa PT-S） provides us with a powerful technique to research fundamental particle internal cohesion forces directly and use these data to indicate the flowability. In this work, a series of fine （9.4μm） and coarse （60 μm） porous silica gel particle mixtures, and mixtures of fine （28μm） and coarse （72 μm） glass ballotini as well, were used as test powders. The results from these tests agree well with relative flowability determined on our newly driven indicator using WSUMCT. The validation of aerated weighted cohesion （WSA） as a flowability indicator was authenticated by comparing the conducted parameter with established measured Hausner ratio （HR） and angle of repose （AoR）.

关键词： Flowability Cohesion strength Hausner ratio Particle sizeAngle of reposeCohesive powder

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Effect of Fe Content on the Interfacial Reliability of SnAgCu/Fe—Ni Solder Joints

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Journal of Materials Science & Technology 2014年第9期30卷 928-933页

作者： Hao Zhang Qing-Sheng Zhu Zhi-Quan Liu Li Zhang Hongyan Guo Chi-Ming Lai Institute of Metal research Chinese Academy of Sciences Jiangyin Changdian Advanced Packaging Co. Ltd.

Fe-Ni films with compositions of Fe-75Ni, Fe-50Ni, and Fe-30Ni were used as under bump metallization （UBM） to evaluate the interracial reliability of SnAgCu/Fe-Ni solder joints through ball shear test, high temperature storage, and temperature cycling. The shear strengths for Fe-75Ni, Fe-5ONi, and Fe-3ONi solder joints after reflow were 42.57, 53.94 and 53.98 MPa, respectively, which were all satisfied the requirement of industrialization （〉34.3 MPa）. High temperature storage was conducted at 150, 175 and 200 ℃. It was found that higher Fe content in Fe-Ni layer had the ability to inhibit the mutual diffusion at interface region below 150 ℃, and the growth speed of intermetallic compound （IMC） decreased with increasing Fe concentration. When stored at 200 ℃, the IMC thickness reached a limit for all three films after 4 days, and some cracks occurred at the interface between IMC and Fe-Ni layer. The activation energies for the growth of FeSn2 on Fe-30Ni, Fe-5ONi, and Fe-75Ni films were calculated as 246, 185, and 81 kJ/mol, respectively. Temperature cycling tests revealed that SnAgCu/Fe-5ONi solder joint had the lowest failure rate （less than 10%）, and had the best interfacial reliability among three compositions.

关键词： Fe-Ni alloy Under bump metallization (UBM) Intermetallic compound (IMC) Reliability High temperature storage Temperature cycling

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Parallel computation of seismic analysis of high arch dam

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Earthquake Engineering and Engineering Vibration 2008年第1期7卷 1-11页

作者：陈厚群马怀发涂劲成广庆唐菊珍 China Institute of Water Resources and Hydropower research (IWHR) Beijing FEGEN Software Co. Ltd.

Parallel computation programs are developed for three-dimensional meso-mechanics analysis of fully-graded dam concrete and seismic response analysis of high arch dams （ADs）, based on the Parallel Finite Element Program Generator （PFEPG）. The computational algorithms of the numerical simulation of the meso-structure of concrete specimens were studied. Taking into account damage evolution, static preload, strain rate effect, and the heterogeneity of the meso-structure of dam concrete, the fracture processes of damage evolution and configuration of the cracks can be directly simulated. In the seismic response analysis of ADs, all the following factors are involved, such as the nonlinear contact due to the opening and slipping of the contraction joints, energy dispersion of the far-field foundation, dynamic interactions of the dam-foundation- reservoir system, and the combining effects of seismic action with all static loads. The correctness, reliability and efficiency of the two parallel computational programs are verified with practical illustrations.

关键词： high arch dam contraction joints random aggregate model nonlinear seismic response parallelcomputation

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Synthesis of LaPO_4:Ce,Terbium by Co-Precipitation Method

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Journal of Rare Earths 2006年第z2期24卷 137-140页

作者：龙志奇任乐朱兆武崔大力赵娜李明来黄小卫 Grirem Advanced Materials Co. ltd. General Research Institute for Non-Ferrous Metals

The synthesis of precursor of green phosphors, LaPO4: Ce, Tb, by means of co-precipitation with cocurrent flow feed was studied. The effects of the reaction temperature, the kind and concentration of the acid in the bottom water, and the charging rate on the physical properties, such as particle size, were investigated. It is found that the particle size of the powder is controllable by adjusting acidity in bottom water and charging rate. The powder with diameter size of 3 to 5μm was obtained. Its XRD and SEM were analyzed. XRD patterns of the as-prepared green phosphor powders display the typical peaks of CePO4. SEM shows that the morphology of powders is ball-shaped.

关键词： LaPO4:Ce, Tb precursor green phosphors co-precipitation method rare earths

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MULTIAXIAL CREEP-FATIGUE LIFE EVALUATION UNDER PROPORTIONAL LOADING

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Acta Metallurgica Sinica(English Letters) 2004年第4期17卷 355-360页

作者： Y.Noguchi M.Miyahara Corporate research & Development Laboratories Sumitomo Metal Industries Ltd. Amagasaki Hyogo 660-0891 JapanCorporate Research & Development Laboratories Sumitomo Metal Industries Ltd. Amagasaki Hyogo 660-0891 Japan

A new method was proposed for the multiaxial creep-fatigue life evaluation under proportional loadings. Because this method was derived from the strain range partitioning method with a multiaxiality factor, it was possible to consider the influence of both creep-fatigue interaction and multiaxial stress state on fatigue life. In order to predict the combined axial-torsional fatigue life the damage under combined loading was defined as linear summation of the damages under axial loading and torsional loading. Axial-torsional creep-fatigue tests were carried out using tubular specimens of 316LC austenitic stainless steel and the ferritic rotor steel. This rotor steel was developed for the permanent magnet type eddy current retarder in heavy trucks. Experimentally obtained lives of both steels were well corresponded with the lives predicted by the proposed method. It was found that the proposed method was effective in multiaxial fatigue life evaluation under proportional creep-fatigue loadings.

关键词： multiaxial fatigue creep-fatigue proportional loading life evaluation

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An optimal adaptive quantization index modulation watermarking algorithm

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Chinese Optics Letters 2009年第7期7卷 580-584页

作者：朱少敏刘建明 China Electric Power research Institute State Grid Information and Telecommunication Co. Ltd.

A novel adaptive watermarking algorithm in discrete wavelet transform （DWT） based on quantization index modulation （QIM） technique is presented. The host image is decomposed into wavelet subbands, and then the approximation subband is divided into non-overlapping small embedding blocks. The secret watermark bit is embedded into singular value vector of each embedding block by applying QIM. To improve the invisibility and robustness of watermarking system, the quantization step for each embedding block is set by combining statistical model with particle swarm optimization （PSO） algorithm. The experimental results show that the proposed algorithm not only preserves the high perceptual quality, but also effectively stands against joint photographic experts group （JPEG） compression, low-pass filtering, noise addition, scaling, and cropping attacks, etc. The comparison analysis demonstrates that our scheme has better performance than the previously reported watermarking algorithms.

关键词： Adaptive algorithms Digital watermarking Discrete wavelet transforms Watermarking

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