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Synthesis and crystal structure of (E)-[(2-cyclohexenyl) vinyl]triaryltin

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Chinese Journal of chemistry 1998年第1期16卷 22-27页

作者：黄葵傅方信潘华德 department of chemistry Northeast Normal University Changchun Jilin 130024 China Current address: Department of Chemistry Southern Illinois University at Carbondale IL. USA.

(E)-[(2-Cyclohexenyl)vinyl]triaryltin (aryl=phenyl, p-tolyl) were synthesized and characterized by elemental analysis, IR, H-1 NMR spectroscopy. The crystal structure of (E)-[(2-cyclohexenyl)vinyl]triphenyltin was also determined by the X-ray diffraction. Experiments show that this compound has the conjugated system, which makes it have possible bioactivity and antitumor activity.

关键词： organotin compounds crystal structure pi-pi conjugated system

Photophysical properties of heteroaromatic ring-fused(di)benzosiloles

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Science China chemistry 2011年第12期54卷 1937-1947页

作者： SHIMIZU Masaki MOCHIDA Kenji KATOH Masaki HIYAMA Tamejiro department of Material chemistry Graduate School of EngineeringKyoto University Kyoto University Katsura current address:Research & Development Initiative Chuo University

Benzosiloles fused to heterocycles such as thiophene, benzothiophene, and benzofuran, and indole- and benzosilole-fused dibenzosiloles were prepared by palladium-catalyzed intramolecular coupling of the corresponding 2-（arylsilyl）aryl triflates in good to high yields. Molecular and crystal structures of 5,7-dihydro-5,5,7,7-tetrakis（1-methylethyl）bis[1]benzosilolo-[2,3-b：3＇, 2＇-d]thiophene, 6-methyl-12,12-diisopropyl-12H-indololo[3,2-b][1]silafluorene, and 5,5,11,11-tetraisopropyl-5,11H-benzosilolo[3,2-c]silafluorene were determined by X-ray diffraction analysis. The UV absorption spectra of the （di）benzosilole derivafives in cyclohexane red-shifted when compared to 1,1-diisopropyldibenzosilole, indicating that replacing a benzene ring of dibenzosilole by the heterocycles as well as fusion of indole and benzosilole moieties onto dibenzosilole narrowed the HOMO- LUMO gaps of the n-conjugation system. The thiophene-fused benzosiloles were faintly fluorescent in solution and in the solid state, whereas the dibenzosiloles exhibited luminescence with moderate and high quantum yields in cyclohexane and in microcrystals, respectively. In other words, aggregation-induced emission was observed for the dibenzosiloles. Notably, 5,5,11,1 1- tetraisopropyl-5,11H-benzosilolo[3,2-c]silafluorene in microcrystals exhibited violet fluorescence （λmax = 396 nm） with a quantum yield of 0.70. Density functional theory （DFT） calculations of the prepared （di）benzosiloles were also performed.

关键词： absorption benzosflole fluorescence silicon solid-state emission

Stiffness-tunable biomaterials provide a good extracellular matrix environment for axon growth and regeneration

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Neural Regeneration Research 2025年第5期20卷 1364-1376页

作者： Ronglin Han Lanxin Luo Caiyan Wei Yaru Qiao Jiming Xie Xianchao Pan Juan Xing department of Pathophysiology School of Basic Medical SciencesSouthwest Medical UniversityLuzhouSichuan ProvinceChina department of Medicinal chemistry School of PharmacySouthwest Medical UniversityLuzhouSichuan ProvinceChina

Neuronal growth, extension, branching, and formation of neural networks are markedly influenced by the extracellular matrix—a complex network composed of proteins and carbohydrates secreted by cells. In addition to providing physical support for cells, the extracellular matrix also conveys critical mechanical stiffness cues. During the development of the nervous system, extracellular matrix stiffness plays a central role in guiding neuronal growth, particularly in the context of axonal extension, which is crucial for the formation of neural networks. In neural tissue engineering, manipulation of biomaterial stiffness is a promising strategy to provide a permissive environment for the repair and regeneration of injured nervous tissue. Recent research has fine-tuned synthetic biomaterials to fabricate scaffolds that closely replicate the stiffness profiles observed in the nervous system. In this review, we highlight the molecular mechanisms by which extracellular matrix stiffness regulates axonal growth and regeneration. We highlight the progress made in the development of stiffness-tunable biomaterials to emulate in vivo extracellular matrix environments, with an emphasis on their application in neural repair and regeneration, along with a discussion of the current limitations and future prospects. The exploration and optimization of the stiffness-tunable biomaterials has the potential to markedly advance the development of neural tissue engineering.

关键词： alginate axon growth biomaterials extracellular matrix neural repair neurons neuroregeneration polyacrylamide polydimethylsiloxane stiffness

Synthesis of High Magnetic Moment CoFe Nanoparticles via Interfacial Diffusion in Core/Shell Structured Co/Fe Nanoparticles

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Nano Research 2009年第5期2卷 380-385页

作者： Chao Wang Sheng Peng Lise-Marie Lacroix Shouheng Sun department of chemistry Brown UniversityProvidenceRhode Island 02912USA current address:Materials Science Division Argonne National LaboratoryArgonneIL 60439USA

We report the synthesis of high magnetic moment CoFe nanoparticles via the diffusion of Co and Fe in core/shell structured Co/Fe *** an organic solution,Co nanoparticles were coated with a layer of Fe to form a Co/Fe core/shell *** raising the solution temperature led to inter-diffusion of Co and Fe and formation of CoFe alloy *** nanoparticles have high saturation magnetization of up to 192 emu/g CoFe and can be further stabilized by thermal annealing at 600℃.

关键词： CoFe nanoparticles core/shell nanoparticles magnetic nanoparticles chemical synthesis

Rational modulation of fluorophosphate cathode by anionic groups to reduce the polarization behavior for fast-charging sodium-ion batteries

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Journal of Energy chemistry 2025年第1期100卷 509-521页

作者： Xinyuan Wang Fan Zhang Xingyu Zhou Qian Wang Changyu Liu Yangyang Liu Hui Wang Xiaojie Liu Key Laboratory of Synthetic and Natural Functional Molecule of the Ministry of Education College of Chemistry & Materials Science Northwest University

Na3V2（PO4）2O2F （VP） is recognized as a promising cathode material for sodium-ion batteries due to its stable structural framework and high specific *** functional theory （DFT） and finite element simulations show that incorporating SO42-into VP decreases its band gap,lowers the migration energy barrier,and ensures a uniform Na+concentration gradient and stress distribution during charge and discharge ***,the average Na+diffusion coefficient of Na3V2（PO4）1.95（SO4）0.05O2F（VPS-1） is roughly double that of VP,leading to enhanced rate capability (80 C,75.5 mAh g-1) and cycling stability (111.0 mAh g-1capacity after 1000 cycles at 10 C current density) for ***-1 exhibits outstanding fast-charging capabilities,achieving an 80%state of charge in just 8.1 *** assembled VPS-1//SbSn/NPC full cell demonstrated stable cycling over 200 cycles at a high 5 C current,maintaining an average coulombic efficiency of 95.35%.

关键词： Anionic group modulation Polarization behavior Fast-charging Sodium-ion battery Fluorophosphate Cathode

CRACK DETECTION OF STRUCTURE FOR PLANE PROBLEM WITH SPATIAL WAVELETS

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Acta Mechanica Sinica 1999年第1期15卷 39-51页

作者：王泉王大钧苏先樾 current address:Dept.Mechanical Engin. University of South CarolinaUSA department of Mechanics Peking UniversityBeijing 100871China

The structure damage detection with spatial wavelets was approached. First, a plane stress problem, a rectangular plate containing a short crack under a distributed loading on the edge, was investigated. The displacement response data along the parallel and perpendicular lines at different positions from the crack were analyzed with the Haar wavelet. The peak in the spatial variations of the wavelets indicates the direction of the crack. In addition, a transverse crack in a cantilever beam was also investigated in the same ways. For these problems, the different crack positions were also simulated to testify the effectiveness of the technique. All the above numerical simulations were processed by the finite element analysis code, ABACUS. The results show that the spatial wavelet is a powerful tool for damage detection, and this new technique sees wide application fields with broad prospects. (Edited author abstract) 14 Refs.

关键词： damage detection wavelet transform plane problem

A highly enantioselective synthesis of 5- (ι-menthyloxy) -4-substituted-3-chloro-2(5H) -furanones

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Chinese Journal of chemistry 1999年第2期17卷 189-195页

作者：耿哲黄彬陈庆华 department of chemistry Beijing Normal University Beijing 100875 China Current address: Department of Chemistry Capital Normal University Beijing 100037 China.

In this paper, stereocontrolled tandem Michael addition-elimination reaction of the novel chiral source, S-(ι-menthyloxy)-3,4-dichloro-2(5H)-furanone, with various thiols and amines has been investigated. A series of new enantiomerically pure compounds, 5-(ι-menthyloxy)-4-substituted-3-cnloro-2(5H)-furanones, were obtained in good yields with d. e.(?)98% under mild conditions.

关键词： Tandem Michael addition-elimination reaction 5-(ι-menthyloxy)-3 4-dichloro-2 (5H)-furanone enantiomerically pure compound 5-(ι-menthyloxy)-4-substituted-3-chloro-2(5H)-furanone

Twenty years hunting for sulfur in DNA

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Protein & Cell 2010年第1期1卷 14-21页

作者： Shi Chen Lianrong Wang Zixin Deng Laboratory of Microbial Metabolism and School of Life Sciences&BiotechnologyShanghai Jiao Tong UniversityShanghai 200030China current address:department of Cell Biology Harvard Medical SchoolHarvard UniversityBostonMA 02115USA current address:department of Biological Engineering Massachusetts Institute of TechnologyCambridgeMA 02139USA

Here we tell a 20-year long *** began with an easily overlooked DNA degradation(Dnd)phenomenon during electrophoresis and eventually led to the discovery of an unprecedented DNA sulfur modification governed by five dnd *** unusual DNA modification,called phosphorothioation,is the first physiological modification identified on the DNA backbone,in which the nonbridging oxygen is replaced by sulfur in a sequence selective and stereo-specific *** dnd gene clusters have been identified in diverse and distantly related bacteria and thus have drawn immediate attention of the entire microbial scientific ***,we summarize the progress in chemical,genetic,enzymatic,bioinformatical and analytical aspects of this novel postreplicative DNA *** also discuss perspectives on the physiological functions of the DNA phosphorothioate modification in bacteria and their implications.

关键词： DNA sulfur modification DNA phosphorothioate modification DNA degradation

Staged dendrite suppression for high safe and stable lithium-sulfur batteries

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Journal of Energy chemistry 2025年第1期100卷 674-683页

作者： Jun Jiang Zhenjie Lu Yanwen Ding Shujun Liu Zhijie Qi Tian Tang Yunfan Zhang Zhiyuan Ma Jingwen Sun Liang Xue Wenyao Zhang Pan Xiong Xin Wang Junwu Zhu Yongsheng Fu Key Laboratory for Soft chemistry and Functional Materials of Ministry of Education Nanjing University of Science and Technology Jiangsu Pylon Battery Co.Ltd

The unavoidable dendrite growth and shuttle effect have long been stranglehold challenges limiting the safety and practicality of lithium-sulfur ***,we propose a dual-action strategy to address the lithium dendrite issue in stages by constructing a multifunctional surface-negatively-charged nanodiamond layer with high ductility and robust puncture resistance on polypropylene （PP） *** uniformly loaded compact negative layer can not only significantly enhance electron transmission efficiency and promote uniform lithium deposition,but also reduce the formation of dendrite during early deposition *** importantly,under the strong puncture stress encountered during the deterioration of lithium dendrite growth under limiting current,the high ductility and robust puncture resistance（145.88 MPa） of as-obtained nanodiamond layer can effectively prevent short circuits caused by unavoidable lithium *** Li||Li symmetrical cells assembled with nanodiamond layer modified PP demonstrated a stable cycle of over 1000 h at 2 mA cm-2with a polarization voltage of only 29.3 ***,the negative charged layer serves as a physical barrier blocking lithium polysulfide ions,effectively mitigating capacity *** improved cells achieved a capacity decay of only 0.042%per cycle after 700 cycles at 3 C,demonstrating effective suppression of dendrite growth and capacity attenuation,showing promising prospect.

关键词： Lithium-sulfur batteries Staged dendrite suppression Shuttle effect Surface-negatively-charged nanodiamond