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Convenient Synthesis of Host Molecule Containing Se-Se Bond

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Chinese Chemical Letters 1998年第9期9卷 813-814页

作者： Wei Jun KE xiu Fang LIU han Shang XU (Institute of Chemistry, Wuhan University, Wuhan 430072) Institute of Chemistry Wuhan University Wuhan 430072 China

Key intermediate bis[2-amino-4,5-(15-crown-5)phenyl]diselenide was obtained by the convenient redox method. Crown-ether type host molecule containing Se-Se bond 2,11-dioxo-4,5:8,9-di(benzo[4',5']-15-crown-5)-6,7-diselena-3,10,16-triazabicyclo[10,3,1]hexadeca-1(16), 4, 8, 12, 14-pentaene was synthesized with high dillution technique.

关键词： host molecule organoselenium oxidation and reduction high dilution technique

Synthesis of Novel Quaternary Selenide K_2CdSnSe_4

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Chemical Research in Chinese Universities 2010年第4期26卷 514-516页

作者： ZhanG Li-dan han Chun-ying FENG xiu-ling WEI Yong-ge GUO Hong-you College of Sciences Beoing University of Chemical Technology Beijing 100029 P. R. China Department of Chemistry Huaihua Institute Huaihua 418008 P. R. China College of Chemistry and Molecular Engineering Peking University Beoing 100871 P. R. China

A novel quaternary metal selenide, K2CdSnSe4, was synthesized via a molten-salt reaction at 550 ℃. The compound has a one-dimensional structure containing a chain of ∞^1[CdSnSe4]^2- anions separated by K^＋ cations. The crystal belongs to the space group I-4^-2m, with the unit cell parameters a=0.80298（11） nm, b=0.80298（11） nm, c=0.69217（14） nm, α=β=γ=90°. A reflectance spectroscopy study reveals the nature of the semiconductor with an energy gap of 1.7 eV for the compound and it has a strong optical absorotion in a range of 2--5 eV.

关键词： Quatemary metal selenide Solid state synthesis Crystal structure

Therapeutic　Observation　on　Twenty－one　Cases　of　Common　Wart　Treated　by　Acupuncture

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中国针灸 1995年第S2期15卷 299-300页

作者： han Yingguan(xiu Ying Hospital, Hainan Province 570311 )

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ＴｈｅｒａｐｅｕｔｉｃＯｂｓｅｒｖａｔｉｏｎｏｎＴｗｅｎｔｙ－ｏｎｅＣａｓｅｓｏｆＣｏｍｍｏｎＷａｒｔＴｒｅａｔｅｄｂｙＡｃｕｐｕｎｃｔｕｒｅ￥ＨａｎＹｉｎｇｇｕａｎ（ＸｉｕＹｉｎｇＨｏｓｐｉｔａｌ，ＨａｉｎａｎＰｒｏｖｉｎｃｅ５７０３１１）Ｔｗｅｎ...

关键词： Acupuncture one Observation Cases Therapeutic Treated Twenty Wart by of

Scalable synthesis of N-doped Si/G@voids@C with porous structures for high-performance anode of lithium-ion batteries

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Rare Metals 2023年第12期42卷 4091-4102页

作者： Lei Wang Yan Jiang Shao-Yuan Li xiu-Hua Chen Feng-Shuo Xi Xiao-han Wan Wen-Hui Ma Rong Deng Faculty of Metallurgical and Energy Engineering State Key Laboratory of Complex Nonferrous Metal Resources Clean UtilizationKunming University of Science and TechnologyKunming 650093China School of Materials Science and Engineering Yunnan UniversityKunming 650091China School of Science and Technology Pu'erUniversityPu'er 665000China School of Photovoltaic and Renewable Energy Engineering(SPREE) University of New South WalesSydney 2052Australia

The co-utilization of silicon(Si) and graphite(G) has been considered as the preferred strategy to achieve high energy density anode materials,but the effective synergistic integration of Si and graphite is still a challenge and it is necessary to find a scheme to accommodate the large-scale production of Si/graphite *** this work,silicon cutting waste from the photovoltaic industry was used as raw material,mixed with graphite,pitch,and polyvinylpyrrolidone,and subjected to high-energy ball *** mixture was then heated in an Ar atmosphere for the carbon coating,and the resulting Si/graphite/carbon(Si/G/C) composite was etched to remove the thicker SiOx layer formed on the Si surface to allow the pores between the Si and the carbon matrix to obtain Si@voids/G@*** from the integrated structural design and the significantly enhanced electronic conductivity,the Si/G@voids@C composite exhibited the first dischargespecific capacity of 2530 mAh·g^(-1) with an initial coulombic efficiency(ICE) of 86.7%,and the remaining capacity exceeded 1000 mAh·g^(-1) after 550 cycles at 1.5A·g^(-1).Notably,full lithium-ion batteries with a Si/G@voids@C anode and LiFePO_4 cathode delivered a stable capacity of 140 mAh·g^(-1).The synthesis method is facile and cost-effective,providing an integration strategy for Si and G with a potential scheme for large-scale commercial applications.

关键词： Silicon/graphite anodes Surface coating Integration strategy Silicon cutting waste High-energy ball milling Lithium-ion battery(LIB)

Influence of element substitutions on poisoning behavior of ZrV_(2)alloy:theoretical and experimental investigations

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Nuclear Science and Techniques 2023年第7期34卷 253-266页

作者： Shuang Yang Run-Jie Fang Guo Yang Li-Jun Lv Xing-Bo han Wei Liu xiu-Jie He Peng-Fei Zhu School of Mathematics Physics and StatisticsShanghai University of Engineering ScienceShanghai 201620China Shanghai Institute of Applied Physics Chinese Academy of SciencesShanghai 201800China China Nuclear Power Technology Research Institute Co.Ltd Shenzhen 518000China Sino-French Institute of Nuclear Engineering and Technology Sun Yat-Sen UniversityZhuhai 519082China

A ZrV_(2)alloy is typically susceptible to poisoning by impurity gases,which causes a considerable reduction in the hydrogen storage properties of the *** this study,the adsorption characteristics of oxygen on ZrV_(2)surfaces doped with Hf,Ti,and Pd are investigated,and the effect of oxygen on the hydrogen storage performance of the alloy was ***,the adsorption energy,bond-length change,density of states,and differential charge density of the alloy before and after doping are analyzed using the first-principles *** theoretical results show that Ti doping has a limited effect on the adsorption of oxygen atoms on the ZrV_(2)surface,whereas Hf doping decreases the adsorption energy of oxygen on the ZrV_(2)*** atoms are more difficult to adsorb at most adsorption sites on Pd-substituting surfaces,which indicates that Pd has the best anti-poisoning properties,followed by *** analysis of the differential charge density and partial density of states show that the electron interaction between the oxygen atom and surface atom of the alloys is weakened,and the total energy is reduced after Hf and Pd *** on theoretical calculations,the hydrogen absorption kinetics of ZrV_(2),Zr_(0.9)Hf_(0.1)V_(2),and Zr(V_(0.9)Pd_(0.1))_(2) alloys are studied in a hydrogen-oxygen mixture of 0.5 vol%O_(2) at 25℃.The experimental results show that the hydrogen storage capacities of ZrV_(2),Zr_(0.9)Hf_(0.1)V_(2),and Zr(V_(0.9)Pd_(0.1))_(2) decrease to 19%,69%,and 80%of their original values,*** order of alloy resistance to 0.5 vol%O_(2) poisoning is Zr(V_(0.9)Pd_(0.1))_(2)>Zr_(0.9)Hf_(0.1)V_(2)>ZrV_(2).Pd retains its original hydrogen absorption performance to a greater extent than undoped surfaces,and it has the strongest resistance to poisoning,which is consistent with previous theoretical calculations.

关键词： Hydrogen storage ZrV_(2) First-principles Poisoning effect

Nonlinear dynamic analysis and fatigue damage assessment for a deepwater test string subjected to random loads

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Petroleum Science 2016年第1期13卷 126-134页

作者： Kang Liu Guo-Ming Chen Yuan-Jiang Chang Ben-Rui Zhu xiu-Quan Liu Bin-Bin han Centre for Offshore Engineering and Safety Technology China University of Petroleum

The deepwater test string is an important but vulnerable component in offshore petroleum exploration,and its durability significantly affects the success of deepwater test *** the influence of random waves and the interaction between the test string and the riser,a time-domain nonlinear dynamic model of a deepwater test string is *** stress-time history of the test string is obtained to study vibration mechanisms and fatigue development in the test *** recommendations for reducing damage are *** results indicate that the amplitude of dynamic response when the string is subjected to random loads gradually decreases along the test string,and that the von Mises stress is higher in the string sections near the top of the test string and the flex *** addition,the fatigue damage fluctuates with the water depth,and the maximum damage occurs in string sections adjacent to the lower flex joint and in the splash *** measures are proposed to improve the operational safety of deepwater test strings：applying greater top tension,operating in a favorable marine environment,managing the order of the test string joints,and performing nondestructive testing of components at vulnerable positions.

关键词： string fatigue joints performing applying operations durability retrieval sections favorable

Mid-infrared supercontinuum and optical frequency comb generations in a multimode tellurite photonic crystal fiber

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Chinese Physics B 2021年第9期30卷 248-258页

作者： Xu han Ying han Chao Mei Jing-Zhao Guan Yan Wang Lin Gong Jin-Hui Yuan a Chong-xiu Yu Key Laboratory for Special Fiber and Fiber Sensor of Hebei Province School of Information Science and EngineeringYanshan UniversityQinhuangdao 066004China State Key Laboratory of Information Photonics and Optical Communications Beijing University of Posts and Telecommunications(BUPT)Beijing 100876China

We numerically investigate the mid-infrared(MIR)supercontinuum(SC)and SC-based optical frequency comb(OFC)generations when the three optical modes(LP_(01),LP_(02),and LP_(12))are considered in a multimode tellurite photonic crystal fiber(MM-TPCF).The geometrical parameters of the MM-TPCF are optimized to support the multimode propagation and obtain the desired dispersion characteristics of the considered three optical *** the pump pulse with center wavelengthλ=2.5μm,width T=80 fs,and peak power P=18 kW is coupled into the anomalous dispersion region of the LP_(01),LP_(02),and LP_(12)modes of the MM-TPCF,the-40-dB bandwidth of the generated MIR SCs can be up to 2.56,1.39,and 1.12 octaves,respectively,along with good ***,the nonlinear dynamics of the generated SCs are ***,the MIR SCs-based OFCs are demonstrated when a train of 50 pulses at 1-GHz repetition rate is used as the pump source and launched into the MM-TPCF.

关键词： multimode tellurite photonic crystal fiber supercontinuum optical frequency comb mid-infrared spectral region

Advancements in our understanding of circular and long non-coding RNAs in spinal cord injury

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Neural Regeneration Research 2022年第11期17卷 2399-2403页

作者： Yan Zhang Ho Jun Yun Yu Ji Eric Cosky Wen-xiu Zhang Wei han Yu-Chuan Ding Central Laboratory Beijing Luhe HospitalCapital Medical UniversityBeijingChina Department of Neurosurgery Wayne State University School of MedicineDetroitMIUSA Department of General Surgery Beijing Luhe HospitalCapital Medical UniversityBeijingChina

Spinal cord injury(SCI),either from trauma or degenerative changes,can res ult in severe disability and impaired quality of *** the cellular processes and molecular mechanisms that underlie SCI is imperative to identifying molecular targets for potential *** studies have shown that non-coding RNAs,including both long non-coding RNAs(lncRNAs)and circular RNAs(circRNAs),regulate various cellular processes in *** this review,we will describe the changes in lncRNA and circRNA expression that occur after SCI and how these changes may be related to SCI *** evidence for the roles of lncRNAs and circRNAs in neuronal cell death and glial cell activation will also be ***,the possibility that lncRNAs and circRNAs are novel modulato rs of SCI pathogenesis will be discussed.

关键词： circular RNAs function long non-coding RNAs neuronal cells neuronal glia pathogenesis regulation spinal cord injury

Mitochondrial DNA diversity and origin of indigenous pigs in South China and their contribution to western modern pig breeds

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Journal of Integrative Agriculture 2019年第10期18卷 2338-2350页

作者： WANG Chen CHEN Yao-sheng han Jian-lin MO De-lin LI xiu-jin LIU Xiao-hong State Key Laboratory of Biocontrol School of Life SciencesSun Yat-sen UniversityGuangzhou 510006P.R.China CAAS-ILRI Joint Laboratory on Livestock and Forage Genetic Resources Institute of Animal ScienceChinese Academy of Agricultural SciencesBeijing 100193P.R.China International Livestock Research Institute (ILRI) Nairobi 00100Kenya

Indigenous pigs in South China are valuable genetic resources with many specific and unique characters, which have played an important role in the establishment of some western modern pig breeds. However, the origin and genetic diversity of indigenous pigs in South China have not been fully understood. In the present study, we sequenced 534 novel mitochondrial DNA (mtDNA) D-loop and assembled 54 complete mitogenome sequences for all 17 indigenous pig breeds from Fujian, Guangdong, Guangxi and Hainan in South China. These data were analyzed together with previously published homologous sequences relevant to this study. We found that all 13 coding genes of the mitogenomes were under purifying selection, but ND1 had the most variable sites and CYTB contained the most non-synonymous SNPs. Phylogenetic analysis showed that all indigenous pigs in South China were clustered into the D haplogroup with D1a1, D1b, D1c and D1e sub-haplogroups found to be dominant. Haplotype and nucleotide diversities of D-loop sequences ranged from 0.427 to 0.899 and from 0.00342 to 0.00695, respectively, among which all pigs in Guangdong had the lowest diversity. The estimates of pairwise FST, gene flow (Nm) and genetic distance (Da) indicated that most of these indigenous pig breeds differentiated from each other significantly (P<0.05). Among the western modern breeds, Berkshire and Yorkshire had significant Asian matrilineal footprints from indigenous pigs in South China, especially the Spotted pigs distributed in Guangdong and Guangxi. The neutrality test (Fu’s FS) indicated that indigenous pigs from Fujian and Guangxi had gone through recent population expansion events (P<0.05). It is concluded that indigenous pigs in South China were most likely derived from the Mekong region and the middle and downstream regions of Yangtze River through Guangxi and Fujian. Our findings provide a complete and in-depth insight on the origin and distribution pattern of maternal genetic diversity of indigen

关键词： pig South China mitogenome D-loop genetic diversity