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Enrichment of CO from syngas with Cu（I）Y adsorbent by five-bed VPSA

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Frontiers of Chemical Science and Engineering 2013年第4期7卷 472-481页

作者： Shuna LI huawei YANG Donghui zhang Chemical Engineering Research Center State key laboratory of chemical engineering Tianjin University Tianjin 300072 China

Cu（I）Y adsorbent was prepared by reduction of Cu（II）Y which was prepared by ion exchange between the NaY zeolite and a solution of Cu（II） chloride. The dynamic adsorption capacity of Cu（1）Y for CO was calculated by adsorption breakthrough curve measured on a fixed bed at 30~C and 0.006MPa （g） of CO partial pressure. The calculated CO adsorption capacity was 2.14 mmol/g, 37.5 times as much as that of NaY zeolite. The adsorption breakthrough curve experiment was also simulated with Aspen Adsorption software and the results were approxi- mately consistent with experimental results. Then a five- bed VPSA process for separating CO from syngas on this adsorbent was dynamically simulated with Aspen Adsorp- tion software with the adsorption pressure of 0.68 MPa （g） and the desorption pressure of -0.075MPa （g）. The results showed that CO was enriched from 32.3% to 95.16%-98.12%, and its recovery was 88.47%-99.44%.

关键词： Cu(I)Y adsorbent breakthrough curve deso-rption VPSA simulation

Mercury oxidation and adsorption characteristics of potassium permanganate modified lignite semi-coke

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Journal of Environmental Sciences 2012年第12期24卷 2083-2090页

作者： huawei zhang Jitao Chen Peng Liang Li Wang College of Chemical and Environmental Engineering Shandong University of Science and TechnologyQingdao 266590China

The adsorption characteristics of virgin and potassium permanganate modified lignite semi-coke （SC） for gaseous Hg were investigated in an attempt to produce more effective and lower price adsorbents for the control of elemental mercury emission. Brunauer-Emmett- Teller （BET） measurements, X-ray powder diffraction （XRD） and X-ray photoelectron spectroscopy （XPS） were used to analyze the surface physical and chemical properties of SC, Mn-SC and Mn-H-SC before and after mercury adsorption. The results indicated that potassium permanganate modification had significant influence on the properties of semi-coke, such as the specific surface area, pore structure and surface chemical functional groups. The mercury adsorption efficiency of modified semi-coke was lower than that of SC at low temperature, but much higher at high temperature. Amorphous Mn7＋, Mn6＋ and Mn4＋ on the surface of Mn-SC and Mn-H-SC were the active sites for oxidation and adsorption of gaseous Hg~, which oxidized the elemental mercury into Hg2＋ and captured it. Thermal treatment reduced the average oxidation degree of Mn2＋ on the surface of Mn-SC from 3.80 to 3.46. However, due to the formation of amorphous MnOx, the surface oxidation active sites for gaseous Hg0 increased, which gave Mn-H-SC higher mercury adsorption efficiency than that of Mn-SC at high temperature.

关键词： lignite semi-coke elemental mercury potassium permanganate modification removal efficiency

Springback characteristics in U-channel forming of tailor rolled blank

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Acta Metallurgica Sinica(English Letters) 2012年第3期25卷 207-213页

作者： huawei zhang Lizhong LIU Ping HU Xianghua LIU School of Automotive Engineering Faculty of Vehicle Engineering and Mechanics State Key Labora- tory of Structural Analysis for Industrial Equipment Dalian University of Technology Dalian 116024 China Research Institute of Science and Technology Northeastern University Shenyang 110819 China

Residual stress developed during the rolling process of tailor rolled blank （TRB） can affect the springback of finished parts considerably. Springback characteristics of unannealed and annealed TRBs were investigated by means of numerical simulation and experiments taking U-Channel as an example. TRBs were annealed by the annealing process （700 ℃, holding time 10 h）, then stamping and springback processes of unannealed and annealed TRBs were simulated, and corresponding experiments were also carried out. Effects of the transition zone length, the blank thickness, the friction coefficient and the die clearance on the springback of TRB were analyzed. The results demonstrate that the springback of TRB annealed at 700 ~C for 10 h re- duces significantly. For unannealed and annealed U-Channels, the springback of TRB U-Channel is in direct proportion to the die clearance and is in inverse proportion to the transition zone length, the blank thickness and the friction coefficient. Spring- backs of the thinner monolithic （uniform thickness） blank, the thinner side of TRB, the thicker side of TRB and the thicker monolithic blank are sorted in descending order.

关键词： Tailor rolled blank Springback Annealing

Evolution of Pore Size Distribution and Mean Pore Size in Lotus-type Porous Magnesium Fabricated with Gasar Process

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Journal of Materials Science & Technology 2006年第3期22卷 306-310页

作者： Yuan LIU Yanxiang LI huawei zhang Jiang WAN Key Laboratory for Advanced Materials Processing Technology Tsinistry of Education Department of Mechanical En-gineering Tsinghua University Beijing 100084 China

The effect of gas pressures on the mean pore size, the porosity and the pore size distribution of lotus-type porous magnesium fabricated with Gasar process were investigated. The theoretical analysis and the experimental results all indicate that there exists an optimal ratio of the partial pressures of hydrogen PH2 to argon PAr for producing lotus-type structures with narrower pore size distribution and smaller pore size. The effect of solidification mode on the pore size distribution and pore size was also discussed.

关键词： Porous metal Lotus-type structure Gasar process

Antiviral strategies:What can we learn from natural reservoirs?

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Journal of Integrative Plant Biology 2022年第10期64卷 1849-1855页

作者： Wenbo Pan Weiwei Li Lijing Liu huawei zhang Peking University Institute of Advanced Agricultural Sciences Weifang 261325China The Key Laboratory of Plant Development and Environmental Adaptation Biology Ministry of EducationSchool of Life SciencesShandong UniversityQingdao 266237China

Viruses cause many severe diseases in both plants and animals,urging us to explore new antiviral *** their natural reservoirs,viruses live and replicate while causing mild or no *** animals,such as bats,are the predicted natural reservoir of multiple viruses,indicating that they possess broad-spectrum antiviral *** of host defenses against viruses are generally studied independently in plants and *** this article,we speculate that some antiviral strategies of natural reservoirs are conserved between *** verify this hypothesis,we created null mutants of 10-formyltetrahydrofolate synthetase(AtTHFS),an Arabidopsis thaliana homologue of methylenetetrahydrofolate dehydrogenase,cyclohydrolase and formyltetrahydrofolate synthetase 1(MTHFD1),which encodes a positive regulator of viral replication in *** found that disruption of AtTHFS enhanced plant resistance to three different types of plant viruses,including the tomato spotted wilt virus(TSWV),the cucumber mosaic virus(CMV)and the beet severe curly top virus(BSCTV).These results demonstrate a novel antiviral strategy for plant *** further discuss the approaches used to identify and study natural reservoirs of plant viruses,especially those hosting many viruses,and highlight the possibility of discovering new antiviral strategies from them for plant molecular breeding and antiviral therapy.

关键词： antiviral strategy antiviral therapy cropmolecular breeding natural reservoir virus

综采工作面过大落差逆断层回采技术研究与应用

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煤炭技术 2025年第1期44卷 44-47页

作者：张华伟曹庆华河南龙宇能源股份有限公司车集煤矿河南永城476600

落差较大的断层,严重影响采煤工作面的安全生产。逆断层在永夏矿区较为罕见,车集煤矿2902工作面切眼为矿井首次揭露大落差逆断层,通过对大落差逆断层回采技术难题研究分析,对工作面爆破机理及效果反向分析总结,对综采工作面爆破规律摸索... 详细信息

落差较大的断层,严重影响采煤工作面的安全生产。逆断层在永夏矿区较为罕见,车集煤矿2902工作面切眼为矿井首次揭露大落差逆断层,通过对大落差逆断层回采技术难题研究分析,对工作面爆破机理及效果反向分析总结,对综采工作面爆破规律摸索,优化了爆破参数及爆破防崩措施;合理控制回采层位,减少了破岩量;制定了托顶煤控制措施,有效实现了安全快速通过逆断层,对类似构造煤层开采具有较强的参考价值。

关键词：逆断层回采层位顶板控制爆破

Effect of copper on magnetostriction and mechanical properties of TbDyFe alloys

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Journal of Rare Earths 2019年第1期37卷 68-73,M0004页

作者： Naijuan Wang Yuan Liu huawei zhang Xiang Chen Yanxiang Li School of Materials Science and Engineering Tsinghua University Key Laboratory for Advanced Materials Processing Technology Ministry of Education

The intrinsic brittleness of the TbDyFe alloy significantly decreases its mach inability and *** paper aims to improve the toughness of TbDyFe alloy by adding Cu. Various alloys of the type(Tb_(0.3)Dy_(0.7))_(0.37)Fe_(0.63-χ)Cu_χ(χ=0, 0,01.0.03, 0.05, 0.08, 0.1) were fabricated by an arc melting furnace under a high purity argon atmosphere. The microstructure, magnetostrictive properties and mechanical performance were studied systematically. The results show that the (Tb,Dy)Cu phase forms in these alloys upon the addition of Cu. Correspondingly, their toughness improves, attributed to the formation of a (Tb,Dy)Cu phase. Compared to the Cu-free alloy, the fracture toughness (Kic) increases 2-3 times with increasing Cu content. However, the magnetostriction performance of these alloys declines with Cu addition, due to the low-magnetic performance of the (Tb,Dy)Cu phase at room temperature. Compared with other alloys, the alloy with the addition of 1at%Cu shows the best compromise between the saturation magnetostriction and fracture toughness.

关键词： TbDyFeCu alloy Microstructure Magnetostriction Mechanical performance Rare earths

Fabrication of lotus-type porous micro-channel copper by single-mold Gasar technique

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China Foundry 2014年第6期11卷 522-530页

作者： Liu Yuan Zhuo Weijia zhang huawei Li Yanxiang School of Materials Science and Engineering Tsinghua University Key Laboratory for Advanced Materials Processing Technology Ministry of Education

A single-mold Gasar technique was developed to produce lotus-type porous micro-channel copper with uniform porous structure. In this paper the effect of withdrawal rate on the solid/liquid interface morphology and the corresponding porous structure was systematically investigated, especially the pore morphology, pore growth direction, porosity, and pore diameter of porous copper ingots. In addition, a temperature fi eld simulation was carried out based on Pro Cast software to investigate the shape and movement velocity of the solidifying solid/liquid interface. The experimental results show that the solidifi cation interface changes from convex to planar, then to concave shape with an increase in withdrawal rate. The average porosities of copper ingots are constant and independent of the withdrawal rate. The average pore diameter decreases with an increase in withdrawal rate.

关键词： porous metal unidirectional solidifi cation Gasar process withdrawal rate

Manipulating mRNA splicing by base editing in plants

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Science China(Life Sciences) 2018年第11期61卷 1293-1300页

作者： Chenxiao Xue huawei zhang Qiupeng Lin Rong Fan Caixia Gao State Key Laboratory of Plant Cell and Chromosome Engineering Center for Genome EditingInstitute of Genetics and Developmental BiologyChinese Academy of SciencesBeijing 100101China University of Chinese Academy of Sciences Beijing 100049China Hebei Laboratory of Agricultural Water-Saving Center for Agricultural Resources ResearchInstitute of Genetics and Developmental BiologyChinese Academy of SciencesShijiazhuang 050021China

Precursor-mRNAs(pre-mRNA) can be processed into one or more mature m RNA isoforms through constitutive or alternative splicing pathways. Constitutive splicing of pre-mRNA plays critical roles in gene expressional regulation, such as intronmediated enhancement(IME), whereas alternative splicing(AS) dramatically increases the protein diversity and gene functional regulation. However, the unavailability of mutants for individual spliced isoforms in plants has been a major limitation in studying the function of mRNA splicing. Here, we describe an efficient tool for manipulating the splicing of plant genes. Using a Cas9-directed base editor, we converted the 5′ splice sites in four Arabidopsis genes from the activated GT form to the inactive AT form. Silencing the AS of HAB 1.1(encoding a type 2 C phosphatase) validated its function in abscisic acid signaling, while perturbing the AS of RS31 A revealed its functional involvement in plant response to genotoxic treatment for the first time. Lastly,altering the constitutive splicing of Act2 via base editing facilitated the analysis of IME. This strategy provides an efficient tool for investigating the function and regulation of gene splicing in plants and other eukaryotes.

关键词： base editing splicing intron retention alternative 5'splicing site