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A Computational Study on Water-assisted Ammonolysis of N-Methyl β-Sultam

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Chemical Research in Chinese Universities 2006年第1期22卷 94-98页

作者： HE Mao-xia FENg da-cheng YU Ling-juan CAI zheng-ting Institute of Theoretical Chemistry Shandong University Jinan 250100 P. R. China

The ring opening of β-sultam v/a an H2O-assisted ammonolysis process was studied by using Density Functional Theory（DFT） method at the B3LYP/6-31g level as a further step in the theoretical investigation of the ammonolysis reaction of β-sultams. The calculated pathways are analogous to those previously described for the non-assisted ammonolysis reaction. Solvent effects were assessed by using the polarized continuum model（PCM） method. The results show that mode 1 and pathway a in channel Ⅱ are the most favorable ones in both the cases. The energy barrier of the cleavage of C-S bonds producing P1 is the highest among all the energy barriers. The presence of a solvent in the continuum model disfavors the reaction, whereas the participation of water in the ammonolysis reaction plays a positive role and reduces the active energy greatly. The relative energies of all the transition states in the assisted ammonolysis are 20-80 kJ/mol lower than those for the non-assisted reaction.

关键词： Ammonolysis Water-assisted mechanism Density Functional Theory(DFT) β-Sultam

Synthesis and Crystal Structure of 1,3-Trans-1,4-cis- 3,4-di(4-bromophenyl)-1',2',3'-trihydro-1-hydroxy- benzo[g]bicyclo[3.3]octane-2-spiro-2'-indene-1'-one

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Chinese Journal of Structural Chemistry 2006年第2期25卷 187-191页

作者： SHI da-Qing LI zheng-Yi SHI Chun-Ling DOU guo-Lan Department.of Chemistry Xuzhou Normal University Xuzhou Jiangsu 221116 China Key Laboratory of Biotechnology on Medical Plants of Jiangsu Province Xuzhou 221116 China

The title compound C35H30Br2O3 （C32H24Br2O2·CH3COCH3） has been synthesized by the dimerization of 2-（4＇-bromobenzal）-1-indenone induced by low-valent titanium reagent, and characterized by elemental analysis, IR,^1H NMR and X-ray single-crystal diffraction. The crystal belongs to triclinic, space group P1^- with a = 10.273（7）, b = 11.036（7）, c = 13.944（9） ,A°, a = 73.972（9）, β =76.577（10）,γ= 88.871（10）°, V = 1476.3（17）A°^3, Mr = 658.41, Z = 2, Dr = 1.481 g/cm^3, μ（MoKa） = 2.780 mm^-1, F（000） = 668, the final R = 0.0452 and wR = 0.0975. X-ray analysis reveals that the two cyclopentane rings spiro-fused each other adopt envelope conformations, while the other cyclopentane ring （C（1）--C（2）-C（7）-C（9）） is coplanar. In addition, there is a classical intermolecular hydrogen bond O（1）-H（1）...O（2） connecting the adjacent molecules into dimers.

关键词： benzo[g]bicyclo[3.3]octane-2-spiro-2'-indene-1'-one synthesis crystal structure,low-valent titanium

Experimental study on smelting reduction of carbon-bearing manganese briquettes in slag bath

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Journal of Iron and Steel Research International 2018年第4期25卷 417-425页

作者： Bo Zhang da-ping Wang Bin Chen Zhen-jian Su zheng-liang Xue School of Metallurgical and Material Engineering Hunan University of Technology Zhuzhou 412007 Hunan China The State Key Laboratory of Refractories and Metallurgy Wuhan University of Science and Technology Wuhan 430081 Hubei China

The reduction of carbon-bearing manganese briquettes in a slag bath was experimentally investigated at temperatures ranging from 1550 to 1650 ℃. Both the internal temperature and the microstructure evolution of the briquettes were analyzed by differential thermal analysis, scanning electron microscopy and energy-dispersive spectrum analysis, and the smelting reduction mechanism of the carbon-bearing manganese briquettes in the slag bath was further elaborated. The results indicated that the smelting reduction of the briquettes in the slag bath could be divided into three stages, and the aggregation and growth of the metallic particles during the reduction were significantly affected by the slag temperature. Under the experimental conditions, the reduction speed at the initial stage of the carbon-bearing manganese briquettes smelting reduction was controlled by the chemical reaction, whereas the reaction speeds at both the middle and following stages were limited by gaseous diffusion.

关键词： Slag bath Smelting reduction Carbon-bearing briquette Kinetics

Characterization and fine mapping of RTMS10, a semi-dominant reverse thermo-sensitive genic male sterile locus in rice

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Journal of Integrative Agriculture 2022年第2期21卷 316-325页

作者： NI Jin-long WANg De-zheng NI da-hu SONg Feng-shun YANg Jian-bo YAO da-nian College of Agronomy Anhui Agricultural UniversityHefei 230036P.R.China Rice genetics and Breeding Key Laboratory of Anhui Province/Rice Research Institute Anhui Academy of Agricultural SciencesHefei 230031P.R.China

The discovery and application of environment-sensitive genic male sterile(EgMS) rice germplasm provide an easy method for hybrid rice breeding and have made great contributions to hybrid rice production. Typically, the photoperiod-and thermosensitive gMS(P/TgMS) lines utilized in two-line hybrid systems are male sterile under long day or/and high temperature but fertile under short day or/and low temperature conditions. However, Yannong S(Yn S), a reverse TgMS(rTgMS) line, is sterile under low temperature(gh temperature(>29.5℃). Here, we report a genetic study on the rTgMS trait in Yn S. Interestingly, the F1 plants of the cross between Yn S and a cultivar, L422, were male sterile at 22℃ and completely fertile at 27℃. Moreover, the segregation ratio of fertile and sterile individuals in Yn S/L422 F2 populations changed from 1:3.05 to 2.95:1 when the ambient temperature increased, showing that the rTgMS trait exhibits semidominance in Yn S. We further found a locus on chromosome 10, termed RTMS10, which controls the rTgMS trait in Yn S. We then finely mapped RTMS10 to a ~68 kb interval between markers ID13116 and ID1318 by Yn S/L422 BC6 F2 populations. A near iso-genic line(NIL) NL1 from the BC6 F3 generation was developed and the pollen of NL1 became abnormal from the meiosis stage under low temperature. In summary, we identified an rTgMS locus, RTMS10, and provided co-segregated markers, which could help to accelerate molecular breeding of rTgMS lines and better understand the rTgMS trait in rice.

关键词： rice photoperiod-and thermo-sensitive genic male sterile(P/TgMS) reverse TgMS(rTgMS) gene mapping RTMS10

Synthesis and Crystal Structure of a 3-D Hydrogen-bonded Supramolecular Decavanadate Compound [habo]_6[V_(10)O_(28)]·2C_3H_7OH·2H_2O

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Chinese Journal of Structural Chemistry 2005年第10期24卷 1186-1192页

作者： CHEN Lian LIN zheng-Zhong JIANg Fei-Long YUAN da-Qiang HONg Mao-Chun State Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of Matter The Chinese Academy of Sciences Fuzhou Fujian 350002 China graduate School of the Chinese Academy of Sciences Beijing 100039 China

A new inorganic-organic hybrid supramolecular compound [habo]6[V10O28]·2C3H7OH·2H2O 1 （abo = R（-）-2-amino-1-butanol） has been synthesized from VO2^＋ in organic solvents and its crystal structure was reported as follows： monoclinic, space group P21/n, a = 11.419（9）, b = 16.811（16）, c = 15.521（12） A, β= 102.98（2）°, V= 2903（4） A^3, Z = 4, C15H46N3O19V5, Mr = 827.25, Dc = 1.893 g/cm^3, 2（MoKα） = 0.71073 A, μ = 1.636 mm^-1, F（000） = 1696, the final R = 0.0696 and wR = 0.1361 for 4641 observed reflections with I 〉 2σ（I）. The compound is based on decavanadate clusters [V10O28]^6-. The hydrogen bonding interactions among habo^＋ cations, solvents and decavanadate clusters extend 1 into a three-dimensional supramolecular architecture.

关键词： decavanadate hydrogen bond three-dimensional crystal structure

Spontaneous anchoring Cl intoα-Co(OH)_(2) as efficient and stable oxygen reduction electrocatalysts for seawater battery

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Rare Metals 2024年第7期43卷 3074-3083页

作者： Wang zheng Xue-Rong zheng Qi Lu Yan-Hui Cao Yang Wang hai-Peng Fu Jin-Feng Zhang Yi-da Deng Wen-Bin Hu School of Materials Science and Engineering Key Laboratory of Advanced Ceramics and Machining Technology of Ministry of EducationTianjin UniversityTianjin 300072China State Key Laboratory of Marine Resource Utilization in South China Sea School of Materials Science and EngineeringHainan UniversityHaikou 570228China Key Laboratory of Electromagnetic Processing of Materials Ministry of EducationNortheastern UniversityShenyang 110819China

Seawater battery is an advanced energy storage system that enables conversion of chemical energy to electricity by consuming metals,dissolved oxygen and seawater in anode,cathode and electrolyte,***,the oxygen reduction reaction(ORR)activity and stability of electrocatalysts can be easily deactivated due to the severe Cl~-permeation and corrosion in seawater ***,we developed a structural buffer engineering strategy by spontaneously anchoring Cl~-intoα-Co(OH)_(2) as efficient and stable ORR electrocatalysts,in which the ultrathinα-Co(OH)_(2) nanosheets were synthesized using an ultrafast solution high-temperature shock(SHTS)*** large lattice space(~0.8 nm)of layeredα-Co(OH)_(2) ensured the spontaneously penetration of Cl~-into the lattice structure and replaced part of OH~-to formα-Co(OH)_(2-x)Cl_*** continuous leaching and compensating of saturated Cl inα-Co(OH)_(2-x)Cl_x could enhance the Cl~-corrosion resistance and modulate electronic structure of Co metallic sites,thus improving the ORR electrocatalytic activity and stability in seawater ***α-Co(OH)_(2-x)Cl_x seawater batteries display superior onset and half-wave potentials of 0.71 and 0.66 V,respectively,which are much better than the counterparts ofα-Co(OH)_(2) and ofβ-Co(OH)_(2) with no Cl~-penetrating and no buffer ***α-Co(OH)_(2-x)Cl_x-based seawater batteries display stable open-circuit potential of 1.69 V and outstanding specific capacity of 1345 mAh·g^(-1).

关键词： Seawater battery Oxygen reduction electrocatalyst Solution high-temperature shock Structural buffer engineering

Controlled synthesis of nanosized Si by magnesiothermic reduction from diatomite as anode material for Li-ion batteries

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International Journal of Minerals,Metallurgy and Materials 2020年第4期27卷 515-525页

作者： Li-fen guo Shi-yun Zhang Jian Xie Dong zheng Yuan Jin Kang-yan Wang da-gao Zhuang Wen-quan zheng Xin-bing Zhao State Key Laboratory of Silicon Materials School of Materials Science and EngineeringZhejiang UniversityHangzhou 310027China Key Laboratory of Advanced Materials and Applications for Batteries of Zhejiang Province Hangzhou 310027China hangzhou Branch Zhejiang Zotye Automobile Corporation LimitedHangzhou 310018China Shanghai han Xing Science and Technology Co. Ltd.Shanghai 201322China

Li-ion batteries(LIBs)have demonstrated great promise in electric vehicles and hybrid electric ***,commercial graphite materials,the current predominant anodes in LIBs,have a low theoretical capacity of only 372 mAh·g?1,which cannot meet the everincreasing demand of LIBs for high energy *** Si is considered an ideal form of Si for the fabrication of LIB anodes as Si–C *** of nanoscale Si in a facile,cost-effective way,however,still poses a great *** this work,nanoscale Si was prepared by a controlled magnesiothermic reaction using diatomite as the Si *** was found that the nanoscale Si prepared under optimized conditions(800°C,10 h)can deliver a high initial specific capacity(3053 mAh·g?1 on discharge,2519 mAh·g?1 on charge)with a high first coulombic efficiency(82.5%).When using sand-milled diatomite as a precursor,the obtained nanoscale Si exhibited a well-dispersed morphology and had a higher first coulombic efficiency(85.6%).The Si–C(Si:graphite=1:7 in weight)composite using Si from the sand-milled diatomite demonstrated a high specific capacity(over 700 mAh·g?1 at 100 mA·g?1),good rate capability(587 mAh·g?1 at 500 mA·g?1),and a long cycle life(480 mAh·g?1 after 200 cycles at 500 mA·g?1).This work gives a facile method to synthesize nanoscale Si with both high capacity and high first coulombic efficiency.

关键词： silicon anode magnesiothermic reduction diatomite Li-ion batteries

Pharmacological Study on Antitumor Activity of 5-Fluorouracil-1-Acetic Acid and Its Rare Earth Complexes

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Journal of Rare Earths 2000年第2期18卷 140-143页

作者： Yang, zheng-Yin Wang, Liu-Fang Yang, Xin-Ping Wang, da-Wei Li, Yu-Ming Dept. of Chem. Lanzhou Univ. Lanzhou 730000 China

The antitumor activity of 5 fluorouracil 1 acetic acid(HFAA) and its lanthanide complexes(La(FAA) 3, Eu(FAA) 3) were studied. The results show that HFAA, La(FAA) 3 and Eu(FAA) 3 with the concentrations of 1 0×10 -5 ～1 0×10 -2 μg·ml -1 inhibit the colony formation of leukemia cells(L 1210 ) and the growth of transplanted tumor sarcoma 180(S 180 ), hepatic carcinoma(HEPA) and ehrlich ascites tumor(EC) as well. The maximum inhibitory rate of Eu(FAA) 3 for S 180 is 38 4%, that HFAA and La(FAA) 3 for EC are 22 4% and 43 4%, respectively. The life prolongation rate of Eu(FAA) 3 for HEPA bearing mice is as long as 284%.

关键词： rare earths antitumor activity 5 fluorouracil 1 acetic acid

A Note on Solutions for Asymptotically Linear Elliptic Systems

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Acta Mathematicae Applicatae Sinica 2008年第3期24卷 511-522页

作者： Lei-ga Zhao Department of Mathematics Beijing University of Chemical Technology 100029 Beijing China Academy of Mathematics and Systems Science Chinese Academy of Sciences Beijing 100190 China Department of Mathematics Yunnan Normal University Kunming 650092 China

In this paper, we are concerned with the elliptic system of{ -△u＋V（x）u=g（x,v）, x∈R^N, -△v＋V（x）v=f（x,u）, x∈R^N, where V（x） is a continuous potential well, f, g are continuous and asymptotically linear as t→∞. The existence of a positive solution and ground state solution are established via variational methods.

关键词： Elliptic system ground state solution variational methods concentration-compactness principle