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Chinese journal of Chemical Engineering 2005年第1期13卷 43-47页

作者：吴素芳 T.H.Beum j.I.Yang j.N.Kim Department of Chemical Engineering Zhejiang University Hangzhou 310027 China Separation Process Research Center Korea Institute of Energy Research 71-2 jang-dong Yusong-ku Daejon 305-343 Korea

The objective of the present study is to characterize the production of hydrogen with a sorptionenhanced steam-methane reaction process using Ca(OH)2 as the CO2 adsorbent. Theoretical equilibrium compositions at different operation conditions were calculated using an iterative method. It was found that with Ca(OH)2 as the CO2 sorbent, the concentration of CO2 adsorption was reduced in the product stream, that gave rise to higher methane conversion and higher H2 concentration. An experimental setup was built to test the theoretical calculation. The effects of sorbents and the particle size of Ca(OH)2 on the concentration of CO2 and H2 were investigated in detail. Results showed that the reactor packed with catalyst and Ca(OH)2 particles produced H2 concentration of 94%. It was nearly 96% of the theoretical equilibrium limit, much higher than H2 equilibrium concentration of 67.5% without CO2 sorption under the same conditions of 500℃, 0.2 MPa pressure and a steam-to-methane ratio 6. In addition, the residual mole fraction of CO2 was less than 0.001.

关键词： hydrogen reactive-adsorption calcium hydroxide steam-methane reforming

Study on the fatigue and wear characteristics of four wheel materials

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journal of Modern Transportation 2013年第3期21卷 182-193页

作者： g.Y.Zhou j.H.Liu W.j.Wang g.Wen Q.Y.Liu State Key Laboratory of Traction Power Tribology Research Institute Southwest Jiaotong University

The fatigue and wear characteristics of four different steel wheel materials are investigated in detail by using rolling contact fatigue and wear bench tests on a jD-1 apparatus, analyzing chemical composition and hardness, and performing profile analysis and micro-morphology analysis. The wear and fatigue behavior of one of the materials under different operation speeds is also investigated. The results show that the wear resistance of the materials has a positive correlation with their carbon content, while fatigue resistance has a negative correlation. Based on hardness analysis as a function of depth into the specimen, the thickness of layers with a steep hardness gradient has a negative correlation with the initial surface hardness in the tests using different materials. The hardness increments, however, have a positive correlation with initial surface hardness. The rolling tests on one material using different rotation speeds show that the hardness increments and the thickness of layers with a steep hardness gradient increase with the rotation speed. The analyses and experimental results demonstrate that two of the four materials exhibit good wear resistance and rolling contact fatigue resistance, making them suitable for either highspeed or heavy axle railroad operations.

关键词： Wheel material . Fatigue . Wear . Hardness

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电流强化铝合金CO_2激光焊接

中国激光 2004年第3期31卷 359-362页

作者：肖荣诗左铁钏 gnter Ambrosy Helmut Hgel 北京工业大学激光工程研究院国家产学研激光技术中心北京100022 Institut fr Strahlwerkzeuge University of Stuttgart

介绍了一种利用电流的磁流体动力学效应强化铝合金CO2 激光焊接的方法及初步试验结果。在激光焊接过程中 ,通过一个布置于熔池前方的附加电极向熔池提供电流 ,该电流在熔池中产生磁场和电磁力 ,致使熔池运动状态及相应的热交换条件发生... 详细信息

介绍了一种利用电流的磁流体动力学效应强化铝合金CO2 激光焊接的方法及初步试验结果。在激光焊接过程中 ,通过一个布置于熔池前方的附加电极向熔池提供电流 ,该电流在熔池中产生磁场和电磁力 ,致使熔池运动状态及相应的热交换条件发生改变 ,从而提高激光能量的有效利用率和加工效率、控制焊缝成型。利用该方法 ,焊缝深度最高增加约 32 % ,面积增加约 2 0 % ,而焊缝宽度减小约 2 8%

关键词： CO2激光焊接电流强化磁流体动力学效应铝合金

Sorption Recovery of gold Thiosulphate Complexes

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Chinese journal of Chemical Engineering 2002年第1期10卷 123-127页

作者： A.g.Kholmogorov O.N.Kononova g.L.Pashkov Y.S.Kononov Institute of Chemistry and Chemical Technology Siberian Department of the Academy of Science 俄罗斯 Krasnoyarsk 660049 Department of Chemistry Krasnoyarsk State University 俄罗斯 Krasnoyarsk 660041

The gold sorption from thiosulphate solutions on carbon sorbents and on anion exchangers was studied. It was shown that the anion exchangers AV-17-10P and AP-100 are the most effective and selective at pH=5-8. These a... 详细信息

关键词： gold thiosulphate complexes sorption recovery anion exchangers

Extreme matter compression caused by radiation cooling effect in gigabar shock wave driven by laser-accelerated fast electrons

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Matter and Radiation at Extremes 2021年第2期6卷 1-7页

作者： S.Yu.gus’kov P.A.Kuchugov g.A.Vergunova P.N.Lebedev Physical Institute of the Russian Academy of Sciences MoscowRussia Keldysh Institute of Applied Mathematics of the Russian Academy of Sciences MoscowRussia

Heating a solid material with laser-accelerated fast electrons is a particularly useful method for generating a plane powerful shock wave with a pressure of several hundred or even thousands of Mbar in the *** the front of such a powerful shock wave,dense plasma is heated to a temperature of several ***,a high rate of radiation energy loss occurs even in low-Z *** this paper,the strong compression of matter due to radiation cooling in a gbar shock wave driven by fast electrons is studied using both computational and theoretical *** is shown that the effect of radiation cooling leads to compression of matter in the peripheral region of the shock wave to a density several times greater than the density at its *** a solid material by a petawatt flux of laser-accelerated fast electrons offers the opportunity to surpass the gigabar pressure level of plane shock waves generated by the impact of laser-accelerated *** pressures of about 100 gbar can be achieved under laboratory conditions only when a spherical target is imploded under the action of a terawatt laser pulse.

关键词： laser shock wave

generating optical supercontinuum and frequency comb in tenuous plasmas

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Matter and Radiation at Extremes 2021年第5期6卷 13-22页

作者： Kenan Qu Nathaniel j.Fisch Department of Astrophysical Sciences Princeton UniversityPrincetonNew Jersey 08544USA

There are several mechanisms by which the frequency spectrum of a laser broadens when it propagates at near-relativistic intensity in a tenuous *** on one-dimensional effects,we identify two strong optical nonlinearities,namely,four-wave mixing(FWM)and forward Raman scattering(FRS),for creating octave-wide *** dominates the interaction when the laser pulse is short and intense,and its combination with phase modulation produces a symmetrically broadened *** dominates when the laser pulse is long and relatively weak,and it broadens the laser spectrum mainly toward lower frequencies and produces a frequency *** frequency chirping combined with group velocity dispersion compresses the laser pulse,causing higher peak intensity.

关键词： optical spectra scattering

Vascularization and osteogenesis in ectopically implanted bone tissue-engineered constructs with endothelial and osteogenic differentiated adipose-derived stem cells

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World journal of Stem Cells 2021年第1期13卷 91-114页

作者： jelena g Najdanović Vladimir j Cvetković Sanja T Stojanović MarijaĐVukelić-Nikolić jelena MŽivković Stevo j Najman Department of Biology and Human genetics Department for Cell and Tissue Engineering Faculty of MedicineUniversity of NišNiš18108Serbia Department of Biology and Ecology Faculty of Sciences and MathematicsUniversity of NišNiš18106Serbia

BACKgROUND A major problem in the healing of bone defects is insufficient or absent blood supply within the *** overcome this challenging problem,a plethora of approaches within bone tissue engineering have been developed *** in mind that the interplay of various diffusible factors released by endothelial cells(ECs)and osteoblasts(OBs)have a pivotal role in bone growth and regeneration and that adjacent ECs and OBs also communicate directly through gap junctions,we set the focus on the simultaneous application of these cell types together with platelet-rich plasma(PRP)as a growth factor reservoir within ectopic bone tissue engineering *** To vascularize and examine osteogenesis in bone tissue engineering constructs enriched with PRP and adipose-derived stem cells(ASCs)induced into ECs and *** ASCs isolated from adipose tissue,induced in vitro into ECs,OBs or just expanded were used for implant construction as followed:BPEO,endothelial and osteogenic differentiated ASCs with PRP and bone mineral matrix;BPUI,uninduced ASCs with PRP and bone mineral matrix;BC(control),only bone mineral *** 1,2,4 and 8 wk after subcutaneous implantation in mice,implants were extracted and endothelial-related and bone-related gene expression were analyzed,while histological analyses were performed after 2 and 8 *** The percentage of vascularization was significantly higher in BC compared to BPUI and BPEO constructs 2 and 8 wk after *** had the lowest endothelial-related gene expression,weaker osteocalcin immunoexpression and Spp1 expression compared to BPUI and ***-related gene expression and osteocalcin immunoexpression were higher in BPUI compared to BC and *** had a higher percentage of vascularization compared to BPUI and the highest CD31 immunoexpression among examined *** Vwf,endothelial-related gene expression in BPEO had a later onset and was upregulated and well-balanced during in viv

关键词： Adipose-derived stem cells Endothelial-related genes Bone-related genes Ectopic osteogenesis Vascularization Platelet-rich plasma

MCNP-ORIgEN耦合通用程序(MOCUP) 的基准验证与实用化(英文)

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核动力工程 2003年第4期24卷 332-337页

作者：王侃 TPLou E greenspan j Vujic 清华大学工程物理系北京100084 美国加州大学伯克利分校核工程系 ca94720

本文的目的是将MOCUP程序实用化,以用于燃耗分析。选取了2个资料完整的基准问题以验证MOCUP程序本身和应用方法。一个基准题是压水堆的栅元燃耗问题(含3种状况);另一个是快堆的燃耗问题。适当选取程序的有关参数后,将MOCUP的计算结果同... 详细信息

本文的目的是将MOCUP程序实用化,以用于燃耗分析。选取了2个资料完整的基准问题以验证MOCUP程序本身和应用方法。一个基准题是压水堆的栅元燃耗问题(含3种状况);另一个是快堆的燃耗问题。适当选取程序的有关参数后,将MOCUP的计算结果同实验结果和/或其它程序计算结果相比较,可得如下结论:①除极个别特例外,MOCUP程序计算得到的同位素成分结果处于其它程序计算结果的范围之内;②与实验测量数据相比,MOCUP程序计算得到的锕系元素浓度的误差均小于11%,绝大多数小于5%;裂变产物浓度的误差小于10%,除 149Sm之外;③MOCUP程序计算得到的反应性随燃耗变化的结果与所报告的其它结果吻合很好。

关键词：燃耗分析基准题目 MOCUP

症状缓解而不是囊肿缩小决定了肝囊肿抽吸硬化疗法的成功

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国际医学放射学杂志 2019年第4期 503-504页

作者：吴越 M.K.Neijenhuis T.F.M.Wijnands W.Kievit M.Ronot T.j.g..evers j.P.H.Drenth Department of gastroenterology and Hepatology Radboud University Medical Center

摘要目的分析对于抽吸硬化治疗成功的病人,症状缓解的定量评估是否较囊肿体积缩小是更好的预估指标。方法从随机对照试验(NCT02048319)中纳入有症状的、大的

关键词：囊肿体积 PLD 抽吸硬化症状缓解肝囊肿