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Synthesis and kinetics of non-isothermal degradation of acetylene terminated silazane

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Chinese Chemical Letters 2011年第2期22卷 139-142页

作者： wei jian han Li Ye Ji Dong Hu Tong Zhao Laboratory of Advanced Polymer Materials Center for Molecular ScienceInstitute of ChemistryChinese Academy of Sciences Beijing 100190China Graduate University of the Chinese Academy of Sciences Beijing 100190China

Novel acetylene terminated silazane compounds,with three types of substituent,were synthesized by the aminolysis of dichlorosilane with 3-aminophenylacetylene（3-APA）.Thermal property of the compounds is studied by thermogravimetry analysis （TGA）.It shows that the acetylene terminated silazane has high temperature *** char yield at 1000℃is 77.6,81.9 and 68.7 wt%for methyl,vinyl,and phenyl substituted silazane,*** pyrolysis kinetics of the silazane is investigated by non-isothermal thermogravimetric *** pyrolysis undergoes three stages,which is resolved by *** kinetic parameters are calculated by the Kissinger *** role of functionalities on the thermal resistance is *** vinyl-silazane exhibits higher thermal stability because of higher cross-linking density.

关键词： Silazane Thermal properties Pyrolysis kinetics

Synthesis of tetraphenylene derivatives and their recent advances

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National Science Review 2017年第6期4卷 892-916页

作者： jian-wei han Xiao-Shui Peng Henry N.C.Wong Shanghai-Hong Kong Joint Laboratory in Chemical Synthesis Shanghai Institute of Organic ChemistryChinese Academy of Sciences Key Laboratory for Advanced Materials Institute of Fine Chemicals School of Chemistry & Molecular Engineering East China University of Science and Technology Department of Chemistry Center of Novel Functional Molecules Institute of Molecular Functional Materials and State Key Laboratory of Synthetic ChemistryThe Chinese University of Hong Kong

The synthetic strategies towards tetraphenylene derivatives are comprehensively summarized in this *** advances in the functionalized tetraphenylene skeleton for research into their structurally unique properties are ... 详细信息

关键词： tetraphenylene aromatic chiral carbocycles eight-membered rings

Spontaneous coronary artery rupture after lung cancer surgery:A case report and review of literature

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World Journal of Cardiology 2024年第2期16卷 92-97页

作者： Ying-Ding Ruan jian-wei han Department of Thoracic Surgery The First People's Hospital of JiandeJiande 311600Zhejiang ProvinceChina

BACKGROUND Spontaneous coronary artery rupture(SCAR)is a rare and life-threatening complication after lung cancer *** present a case of SCAR following left upper lobectomy,successfully managed through emergency thoracotomy and coronary artery *** SUMMARY A 61-year-old male patient underwent left upper lobectomy and mediastinal lymph node dissection for lung *** surgery was performed using singleport video-assisted thoracoscopic surgery,and there were no observed complications during the ***,19 h after surgery,the patient experienced chest discomfort and subsequently developed severe symptoms,including nausea,vomiting,and a drop in blood *** measures were taken,leading to the diagnosis of *** patient underwent emergency thoracotomy and coronary artery ligation,successfully stopping the bleeding and stabilizing the *** postoperative complications,the patient made a successful recovery and was discharged from the *** SCAR is a rare but life-threatening complication following lung cancer *** thoracotomy has been shown to be a life-saving measure,while stenting is not the preferred initial approach.

关键词： Spontaneous coronary artery rupture Lung cancer Surgery Case report

Synthesis of new borazines containing crosslinkable groups

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Chinese Chemical Letters 2008年第12期19卷 1398-1400页

作者： Shao Hua Dong Zhi Min Zheng wei jian han Tong Zhao Cai Hong Xu Beijing National Laboratory for Molecular Science （BNLMS） Institute of Chemistry Chinese Academy of Sciences Beijing 100190 China Graduate School of the Chinese Academy of Sciences Beijing 100039 China

Three new functional group containing borazine derivatives, 2,4,6-tri（allylamino）borazine, 2,4,6-tri（3-ethynylanilino）borazine, and 2,4,6-tri（4-propargyl oxyanilino）borazine were synthesized by aminolysis reaction of 2,4,6-trichloroborazine ClaB3N3H3（TCB）. The new compounds were characterized by infrared （IR） spectra, nuclear magnetic resonance （NMR）, and mass spectrometry （MS）.

关键词： Aminolysis Crosslinkable groups

Distribution of charged lunar dust in the south polar region of the moon

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Chinese Physics B 2022年第4期31卷 441-448页

作者： Qing Xia Ming-Hui Cai Liang-Liang Xu Rui-Long han Tao Yang jian-wei han National Space Science Center Chinese Academy of SciencesBeijing 100190China School of Astronomy and Space Science University of Chinese Academy of SciencesBeijing 100049China

Lunar dust is one of the most threatening problems confronting the return of human beings to the *** this work we studied the spatial distribution behavior of charged lunar dust in the solar wind plasma environment in the south polar region of the moon and considered the influence of a mini-crater using Spacecraft Plasma Interactions *** distribution of dust and plasma at low solar altitude angles of 20°and 0°was studied,and the spatial density of lunar dust was~10^(10.4)m^(-3)and~10^(11.5)m^(-3),*** is because a higher surface potential will result in transportation of small dust particles and photoelectrons can also neutralize positively charged lunar *** dust density in the plasma void region created by a mini-crater with a 5 m high wall was *** obtained a quasi-neutral electric environment in the plasma void region of the mini-crater,and the dust density was about a magnitude lower than that in other *** dust risk to a spacesuit is much lower on the nightside than on the dayside,but there is severe charged lunar dust transport in the region between light and shade,which is dominated by the difference in surface and plasma potential caused by photoelectrons.

关键词： lunar dust south polar region solar wind mini-crater

Synthesis and pyrolysis of oligo(methylsilylene)-ethynylene polymer to near-stoichiometric SiC ceramic

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Chinese Chemical Letters 2010年第11期21卷 1299-1302页

作者： wei jian han Ji Dong Hu 1Li Ye Song Shi Xue Yu Tao Tong Zhao Laboratory of Advanced Polymer Materials Center for Molecular Science Institute of Chemistry Chinese Academy of Sciences Beijing 100190 China Graduate University of the Chinese Academy of Sciences Beijing 100190 China National Key Laboratory of Advanced Functional Composite Materials Aerospace Research Institute of Materials & Processing Technology Beijing 100076 China

Oligo（methylsilylene）-ethynylene polymer with crosslinkable ethynyl unit in the main chain was synthesized by condensation ofα,ω-dicholorooligo（methylsilane） with *** as-synthesized polymer was characterized by GPC,FT-IR and *** results showed ethynyl group was successfully introduced to the polymer main *** ceramic yield was dramatically increased by the cross-polymerization of ethynyl group,and the excess silicon of PMS was *** （C/Si=1.17） and partial crystallizationβ-SiC monoliths were obtained by pressureless pyrolysing PSPA at 1200℃in a high yield（73.6 wt%）.

关键词： Polymethylsilane Silicon carbide Precursor Crosslinkable

Relapse of acute lymphoblastic leukemia in the pancreas after allogeneic bone marrow transplantation

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Chinese Medical Journal 2010年第22期123卷 3364-3366页

作者： ZHAO Xiao-mu ZhanG Zhong-tao LI jian-she han wei Department of General Surgery Beijing Friendship Hospital Capital Medical University Beijing 100050 China

The occurrence of metastatic lesions in the pancreas of patients with cancer, including hematological cancers,is uncommon （1.6%-37.5%） and of these, the majority of patients will have widespread disease.1-7 Isolated potentially resectable pancreatic metastases are rarely seen. Resection of metastatic tumors of the pancreas has been reported, but its role in improving survival rates or quality of life is not clear.7,8 However,

关键词： pancreas acute leukemia relapse allogeneic bone marrow transplantation

Soil Phosphorus Dynamics as Influenced by Land Use Changes in Humid Tropical, Southwest China

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Pedosphere 2005年第1期15卷 24-32页

作者： YANGJing-Cheng HUANGjian-Hui PANQing-Min TANGjian-wei hanXing-Guo LaboratoryofQuantitativeVegetationEcology InstituteofBotanyChineseAcademyofSciencesBeijing1000g3China LaboratoryofQuantitativeVegetationEcology InstituteofBotanyChineseAcademyofSciencesBeijing1000g3China／／BeijingNaturalHistoryMuseumBeijing100050China XishuangbannaTropicalBotanicalGarden ChineseAcademyofSciencesYunnan666303China

Land use changes can greatly influence soil phosphorus (P) dynamics, especially when converting native forests to agricultural land. Soils in Xishuangbanna, which is one of southwest China s tropical areas that maintain fragments of primary forests, were studied to a) evaluate the effect of two common land use changes, conversion of forests to agricultural land or rubber tree plantation, on the dynamics of available P and total P in bulk soils as well as total P in particle size fractions; b) assess the rel…

关键词： BRAZILIAN AMAZON ORGANIC-MATTER NUTRIENT POOLS DEFORESTATION FRACTIONS PHOSPHATE BIOMASS LOSSES FIRE

私营企业国际化战略、出资人异质性与企业绩效

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山西财经大学学报 2016年第4期38卷 74-86页

作者：陈东韦健涵南京大学经济学院江苏南京210093 浙江大学经济学院浙江杭州310027

以中共中央统战部等四部门2012年对全国范围内私营企业抽样调研数据为样本,实证检验了国际化战略、出资人背景异质性与企业绩效之间的关系。研究发现:有管理经历、有对外经历、中共党员、担任人大代表和政协委员、高学历的出资人倾向于... 详细信息

以中共中央统战部等四部门2012年对全国范围内私营企业抽样调研数据为样本,实证检验了国际化战略、出资人背景异质性与企业绩效之间的关系。研究发现:有管理经历、有对外经历、中共党员、担任人大代表和政协委员、高学历的出资人倾向于国际化战略;国际化对企业绩效有显著的正向影响;出资人背景与国际化战略的交互作用在多方面显著调节企业绩效。本文对这些规律进行了归纳,并从出资人背景角度对提高国际化绩效进行了探讨。

关键词：私营企业国际化战略出资人异质性企业绩效