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草海沉积物有机质空间分布与来源识别

绵阳师范学院学报 2017年第8期36卷 1-9页

作者：杨海全陈敬安宋以龙王敬富陆顶盘中国科学院地球化学研究所环境地球化学国家重点实验室贵州贵阳550081 中国科学院大学北京100049

本文选取草海湿地这一典型高原湖泊湿地作为研究对象,分析了17个表层沉积物和3根代表性湖区沉积物柱芯总有机碳(TOC)含量、有机碳δ^(13)C及C/N值,探讨了草海湿地表层沉积物和三个重点湖区不同深度沉积物有机质的主要来源,并利用有机碳... 详细信息

本文选取草海湿地这一典型高原湖泊湿地作为研究对象,分析了17个表层沉积物和3根代表性湖区沉积物柱芯总有机碳(TOC)含量、有机碳δ^(13)C及C/N值,探讨了草海湿地表层沉积物和三个重点湖区不同深度沉积物有机质的主要来源,并利用有机碳δ^(13)C和C/N值对表层沉积物有机碳来源进行定量分析.结果表明:草海表层沉积物中TOC含量、δ^(13)C和C/N值变化范围分别为6.86%~34.85%,-28.49%^-18.19%,7.36~11.12;表层沉积物有机碳主要来源于藻类生产和沉水植物,沉水植物贡献率为49.7%,藻类初级生产的贡献率为48.8%,而陆源输入只对东部湖区有较小影响;东部湖区上部沉积物有机碳主要来源于藻类,底部受到藻类生长、陆源输入及沉水植物共同影响。

关键词：草海沉积物有机质来源稳定碳同位素碳氮比

Mg-Zn-Y-Nd coated with citric acid and dopamine by layer-by-layer self-assembly to improve surface biocompatibility

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Science China(Technological Sciences) 2018年第8期61卷 1228-1237页

作者： chen Li LI jingan CHANG JiaWei JIN ShiBo WU Di YAN HaoHao WANG XiaoFeng GUAN ShaoKang School of Materials Science and Engineering Zhengzhou UniversityZhengzhou450001China School of Life Science Zhengzhou UniversityZhengzhou 450001 China National Center for International Research of Micro-nano Molding Technology & Key Laboratory for Micro Molding Technology of Henan Province Zhengzhou 450001 China

Magnesium alloy has been generally accepted as an important biodegradable material on cardiovascular stent development for a long time. However, its limited biocompatibility, especially delayed endothelialization process restricts its further application. In this contribution, we modified the Mg-Zn-Y-Nd alloy surface with citric acid and dopamine via a layer-by-layer self-assembly assay, aiming at improving the biocompatibility of the magnesium alloy. The citric acid/dopamine(CA/PDA) layer exhibited a remarkable suppression of platelet activation/aggregation and thrombosis under 15 dyn/cm2 blood flowing. Inhibition on vascular smooth muscle cells growth and macrophages attachment/activation were also observed on this layer. In particular, the CA/PDA layer presented a promoted property for the vascular endothelial cells growth and spreading compared with the bare magnesium alloy, suggesting the pro-endotelialized function. In conclusion, this research may support potential application on surface modification of magnesium alloy based cardiovascular stents for better biocompatibility.

关键词： cardiovascular stent Mg-Zn-Y-Nd alloy biocompatibility layer-by-layer self-assembly citric acid dopamine

Microstructure Evolution of Primary γ′ Phase in Ni3Al-Based Superalloy

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Acta Metallurgica Sinica(English Letters) 2020年第12期33卷 1709-1726页

作者： Xin He Jianbo Zhang Yuanyi Peng jingan Li Jian Ding Chang Liu Xingchuan Xia Xueguang chen Yongchang Liu School of Material Science and Engineering Hebei University of TechnologyTianjin 300130China School of Material Science and Engineering Tianjin UniversityTianjin 300130China

In this work,water cooling,air cooling(AC)and furnace cooling(FC)were applied to investigate the effect of cooling rate on microstructure evolution of primaryγ′in a newly designed Ni3Al-based *** results showed that nucleation rate of primaryγ′increased with increasing cooling *** addition,higher cooling rate shortened growth period of primaryγ′,which made its morphology close to the initial precipitatedγ′.For AC and FC specimens,due to the lower cooling rate,primaryγ′possessed longer growth period and its morphology was mainly due to the evolution of lattice misfit betweenγand primaryγ′.Meanwhile,growth of primaryγ′depended on lattice misfit distribution between its corner and edge ***,primaryγ′morphologies of sphere,cube and concave cube with tip corners were illustrated by considering interaction between elemental diffusion and elastic strain energy.

关键词： Ni3Al-based alloy Primaryγ′ Cooling rate Nucleation rate Lattice misfit

Cardiac infiltration of diffuse large B-cell lymphoma manifesting as sustained ventricular tachycardia:a case report

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Journal of Geriatric Cardiology 2024年第2期21卷 242-245页

作者： Wei chen Kun HUANG Wei-Wei GUO Fan ZHOU De-Ning LIAO Department of Cardiology Shanghai Jingan District Zhabei Central HospitalShanghaiChina Department of Cardiology Shanghai Changzheng HospitalShanghaiChina Department of Hematology Shanghai Jingan District Zhabei Central HospitalShanghaiChina

Cardiac tumors are ***,cardiac metastases can occur in up to 10%of patients with *** cardiac neoplasms,metastases are much more common than primary cardiac tumors.[1]Metastatic cardiac neoplasms most frequently metast... 详细信息

关键词： neoplasms sustained cardiac

Preparation of functional coating on magnesium alloy with hydrophilic polymers and bioactive peptides for improved corrosion resistance and biocompatibility

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Journal of Magnesium and Alloys 2022年第7期10卷 1957-1971页

作者： Lingchuang Bai Yahui Wang Lan chen Jun Wang jingan Li Shijie Zhu Liguo Wang Shaokang Guan School of Materials Science and Engineering Zhengzhou UniversityZhengzhou 450001China Henan Key Laboratory of Advanced Magnesium Alloys Zhengzhou 450002China Key Laboratory of Materials Processing and Mold Technology(Ministry of Education) Zhengzhou 450002China

Biodegradable magnesium alloy stents(MAS)have great potential in the treatment of cardiovascular ***,too fast degradation and the poor biocompatibility are still two key problems for the clinical utility of *** the present work,a functional coating composed of hydrophilic polymers and bioactive peptides was constructed on magnesium alloy to improve its corrosion resistance and biocompatibility in vitro and in ***-Zn-Y-Nd(ZE21B)alloy modified with the functional coating exhibited moderate surface hydrophilicity and enhanced corrosion *** favourable hemocompatibility of ZE21B alloy with the functional coating was confirmed by the in vitro blood ***,the modified ZE21B alloy could selectively promote the adhesion,proliferation,and migration of endothelial cells(ECs),but suppress these behaviors of smooth muscle cells(SMCs).Furthermore,the modified ZE21B alloy wires could alleviate intimal hyperplasia,enhance corrosion resistance and re-endothelialization in vivo transplantation *** results collectively demonstrated that the functional coating improved the corrosion resistance and biocompatibility of ZE21B *** functional coating provides new insight into the design and development of novel biodegradable stents for biomedical engineering.

关键词： Magnesium alloy stent Functional coating Corrosion resistance Biocompatibility Hemocompatibility Endothelialization

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闽江口海蜇生长的研究

台湾海峡 1999年第3期18卷 314-319页

作者：卢振彬戴泉水颜尤明陈利琛陈金淦福建省水产研究所厦门361012 长乐市水产局长乐350200

分别采用高次方程和指数高次方程模拟闽江口海蜇伞径和体重的生长，结果表明海蜇生长明显分３个阶段：５月１０日以前为缓慢生长期；５月１１日至７月３０日为快速生长期；７月３０日以后为衰老期，个体收缩，体重减轻；伞径和体... 详细信息

分别采用高次方程和指数高次方程模拟闽江口海蜇伞径和体重的生长，结果表明海蜇生长明显分３个阶段：５月１０日以前为缓慢生长期；５月１１日至７月３０日为快速生长期；７月３０日以后为衰老期，个体收缩，体重减轻；伞径和体重的最大值分别出现在８月５日和７月３０日；伞径和体重生长速度最大值分别出现在６月２日和６月２５日。据此确定闽江口海哲最佳捕捞期７月３０日，最佳捕捞伞径４９４．１ｍｍ；合理开捕期７月２０日，开捕伞径４６５．８ｍｍ。

关键词：海蜇生长特性最佳捕捞期合理开捕期闽江口

The Strategy of Industrial Clusters to Deal with Disruptive Innovation

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Open Journal of Applied Sciences 2022年第10期12卷 1649-1660页

作者： Jiachun chen Ruiqiu Ou jingan Wang Zhongshan Institute University of Electronic Science and Technology of China Zhongshan China

Disruptive innovation may be a fatal threat to industrial clusters, or it may be a major development opportunity. The key lies in how industrial clusters respond to disruptive innovation. The main obstacles to the development of disruptive innovation in industrial clusters are lock-in and cluster inertia, which originate from the negative effects of cluster system isomorphism. In order to break through the development barriers, industrial clusters need to adopt a targeted overall response strategy, including adopting bottom-up local subversive innovation policies, introducing external knowledge, encouraging spin-off entrepreneurial enterprises, and encouraging alliances and cooperation between incumbent enterprises and entrepreneurial enterprises, etc.

关键词： Industrial Clusters Disruptive Innovation Strategies Entrepreneurial Enterprises

Mechanism and Dynamics of the Addition of Lithium Hydride to Acetylene

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Chemical Research in Chinese Universities 1991年第2期7卷 74-78页

作者： chen Bin, Zhao chengda and Huang jingan (Department of Chemistry, Northeast Normal University, Changchun)

Reaction ergodography for the addition of lithium hydride to acetylene indicates that the lithium hydride, in both monomeric and dimeric forms, reacts with the acetylene via two similar and competitive pathways. Hence... 详细信息

关键词： Reaction ergodography Mechanism Dynamics Lithium hydride Acetylene

Ab Initio Study on the Isomerization and Dehydrogenation of Methylnitrene

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Chemical Research in Chinese Universities 1989年第4期5卷 325-330页

作者： chen Bin, Zhao chengda, Fu Qiang and Huang jingan (Deparment of Chemistry, Northeast Normal University, Changchun)

The ab initio calculations were performed at the RHF/4-31G level with the reaction pathways of the iso-merization and dehydrogenation of methylnitrene by the intrinsic reaction coordinate method. The results show that the transformation from methylnitrene to methylenimine would be very easy. This accountes for the experimental fact that one couldn' t find the methylnitrene, but only obtained the methylenimine in the pyrolysis of methyl azide. The mode-selective study reveals the reaction coordinates (IRC) of isomerization and dehydrogenation of methylnitrene are associated with the molecular deformation mode of 1191 cm-1 and the methyl group unsymmetrical stretch mode, respectively. The coupling between normal coordinates is favourable to select the reaction channel of isomerization.

关键词： ab initio IRC analysis mode-select