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Width of Soliton and the Electron Correlation in Polymer

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Chinese Physics Letters 1996年第3期13卷 211-214页

作者： MA Yun-sheng wu chang-qin FU Rou-li SUN Xin t.4.lee laboratory and department of physics fudan universityshanghai 200433 national laboratory of infrared physics chinese academy of sciencesshanghai 200083

The effect of electron correlation on the width of the soliton in polymer is *** theory shows that the screening plays a key role in the effect of electron correlation on the width of soliton:In weak screenings the width of soliton is reduced by the electron-electron interaction;whereas,,in strong screenings it will be *** physical reason is given at the end.

关键词： soliton Electron Soliton

西藏雄村矿区1号矿体黄铁矿标型特征及其地质意义

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矿物岩石地球化学通报 2024年第2期43卷 372-386页

作者：吴昌益郎兴海张赫王旭辉张鹏邓煜霖娄渝明姜楷成都理工大学地球科学学院成都610059 四川省国土科学技术研究院成都610074 西藏天圆矿业资源开发有限公司西藏日喀则857000

为研究西藏雄村矿区黄铁矿的成因矿物学和找矿矿物学意义,本文对雄村矿区1号矿体主成矿阶段的黄铁矿开展了X射线衍射、热电性、电子探针和LA-ICP-MS分析。结果表明,1号矿体黄铁矿晶胞参数a0为5.41438×10^(-10)~5.41966×10^(-10)m,平均... 详细信息

为研究西藏雄村矿区黄铁矿的成因矿物学和找矿矿物学意义,本文对雄村矿区1号矿体主成矿阶段的黄铁矿开展了X射线衍射、热电性、电子探针和LA-ICP-MS分析。结果表明,1号矿体黄铁矿晶胞参数a0为5.41438×10^(-10)~5.41966×10^(-10)m,平均Δa0值为5.41747×10^(-10)m;体积V为158.7190×10^(-10)~159.1946×10^(-10)m^(3),ΔV平均值为158.9896×10^(-10)m^(3);热电系数α为-336.7~330.6μV/oC。黄铁矿S含量为51.34%~53.44%,平均值为52.92%;Fe含量为44.06%~46.90%,平均值为46.18%,Co/Ni值集中在10附近。结合前人研究成果,我们认为1号矿体主成矿阶段的黄铁矿为岩浆热液成因,主要为N型黄铁矿,形成于硫逸度较低的中高温环境。另外,黄铁矿不是1号矿体的主要载金矿物,预测该矿体处于成矿系统的中下部,在深部具有一定的延伸趋势,但是很可能被后期侵位的黑云母花岗闪长岩破坏,深部找矿潜力不大。

关键词：西藏雄村矿区黄铁矿晶胞参数热电性斑岩型矿床

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大位移井套管磨损预测及剩余强度计算

科学技术与工程 2024年第24期24卷 10227-10234页

作者：曹天宝李忠慧刘剑孟凡奇张武昌油气钻采工程湖北省重点实验室武汉430100 长江大学石油工程学院油气钻完井技术国家工程研究中心武汉430100 中国海洋石油集团有限公司深圳分公司深圳518067

在大位移井钻进过程中,由于水垂比大的特点,钻柱在井下运行形式复杂,造成套管内壁磨损严重,套管强度降低,极大地影响了后续钻井和生产作业。应用基于能量传递的套管磨损效率模型,采取分段法求取管柱侧向力,对套管月牙形磨损进行分析,并... 详细信息

在大位移井钻进过程中,由于水垂比大的特点,钻柱在井下运行形式复杂,造成套管内壁磨损严重,套管强度降低,极大地影响了后续钻井和生产作业。应用基于能量传递的套管磨损效率模型,采取分段法求取管柱侧向力,对套管月牙形磨损进行分析,并依据API(American Petroleum Institute)最小壁厚法,简化月牙状套管磨损,建立套管磨损预测及剩余强度计算方法。利用该模型对南海某大位移井进行计算。结果表明:侧向力是影响套管磨损的主要因素,倒划眼对套管的磨损效果明显强于正常钻进。全井段磨损最严重的位置是狗腿角最大的井段,套管失效的风险最大,是采取防磨措施的关键井段。经计算该井四开作业完成之后,狗腿角最大处的套管磨损深度为1.15 mm,套管强度衰减至原始强度的58.24%,但仍能满足强度要求;该研究成果为南海大位移井套管磨损的防治提供了依据和参考。

关键词：套管磨损磨损机理磨损深度剩余强度计算模型

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烹饪熟度对牛排挥发性风味物质的影响研究

中国调味品 2024年第9期49卷 47-53页

作者：姚力为邓静易宇文刘阳朱开宪吴华昌成都大学食品与生物工程学院成都610106 四川旅游学院烹饪科学四川省高等学校重点实验室成都610100

为探究烹饪熟度对牛排挥发性化合物的影响,文章采用感官分析、电子鼻和GC-IMS分析不同烹饪熟度(生肉、一分熟、三分熟、五分熟、七分熟和九分熟)牛排中挥发性化合物的差异。感官结果表明,随着烹饪熟度的增加,牛排在嫩度、多汁性和外观... 详细信息

为探究烹饪熟度对牛排挥发性化合物的影响,文章采用感官分析、电子鼻和GC-IMS分析不同烹饪熟度(生肉、一分熟、三分熟、五分熟、七分熟和九分熟)牛排中挥发性化合物的差异。感官结果表明,随着烹饪熟度的增加,牛排在嫩度、多汁性和外观上的分数先升高后降低,而在整体风味和整体接受度上其值一直增加,当牛排熟度为九分熟时,整体感官最佳;电子鼻结果表明,样品在T、P传感器上具有较高的值,并且随着烹饪熟度的增加,传感器上的值也在不断增加,说明烹饪熟度会增加样品中挥发性化合物的浓度;GC-IMS结果表明,在样品中共鉴定出88种挥发性化合物,主要是醇类、醛类、酮类和酯类,并且随着熟度的增加,样品中化合物的浓度增加,通过ROAV共计算出12种特征性风味物质(ROAV>1),对样品整体风味具有较高的贡献作用,并且1-辛烯-3-酮的贡献作用最突出;通过Pearson相关性发现,异戊醇(单体、二聚体)、正己醇(单体、二聚体)和2-乙基-3-甲基吡嗪与传感器T、P具有较高的相关性。文章着重分析了不同熟度下牛排挥发性风味物质的变化,为西餐牛排煎制的烹饪工艺优化和品质控制提供了参考依据。

关键词：烹饪熟度牛排挥发性风味物质电子鼻 GC-IMS

星形胶质细胞来源外泌体对氧糖剥夺再复氧后PC12细胞线粒体功能损伤的保护作用

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中国生物化学与分子生物学报 2024年第6期40卷 827-837页

作者：高霄王正薇蔡娜唐智吴昌学齐晓岚官志忠肖雁地方病与少数民族性疾病教育部重点实验室贵阳550004 贵州医科大学分子生物学重点实验室贵阳550004 贵州医科大学学报编辑部贵阳550004

外泌体可以改善由缺氧缺血引起的神经细胞损伤,但星形胶质细胞来源的外泌体(astrocyte-derived exosomes,As-exo)与线粒体功能、线粒体相关内质网膜(mitochondrial associated ER membrane,MAM)的功能及线粒体自噬是否相关目前尚未明确... 详细信息

外泌体可以改善由缺氧缺血引起的神经细胞损伤,但星形胶质细胞来源的外泌体(astrocyte-derived exosomes,As-exo)与线粒体功能、线粒体相关内质网膜(mitochondrial associated ER membrane,MAM)的功能及线粒体自噬是否相关目前尚未明确。本研究旨在探究星形胶质细胞来源外泌体对氧糖剥夺再复氧(oxygen and glucose deprivation/reoxygenation,OGD/R)后PC12细胞线粒体功能、MAM以及线粒体自噬的调控作用。超速离心法提取星形胶质细胞培养基上清中的外泌体并对其进行鉴定。利用活细胞工作站观察到荧光标记后的外泌体在24 h时即在PC12细胞内出现明显的富集现象,同时在激光共聚焦扫描显微镜下观察到外泌体与线粒体出现共定位现象;采用Seahorse细胞能量代谢分仪检测线粒体压力变化:与Control组相比,OGD/R组的基础呼吸、质子漏、最大呼吸和ATP相关呼吸都有明显降低(P<0.05或P<0.01),OGD/R+exo组与OGD/R组相比4项指标都升高且差异具有统计学意义(P<0.05或P<0.01);线粒体和内质网共定位结果表明,MAM受到氧糖剥夺再复氧伤害时,结构出现距离减小的聚合现象,而As-exo处理后MAM聚合现象减弱;流式结果表明,As-exo,一定程度恢复由氧糖剥夺损伤带来的线粒体膜电位降低和ROS升高;Western印迹结果显示,As-exo能显著抑制由OGD/R引起的线粒体自噬相关蛋白张力蛋白同源物诱导的假定激酶1(PTEN induced kinase 1,PINK1)和Parkin蛋白(parkin RBR E3 ubiquitin protein ligase,Parkin)升高,加入As-exo可降低LC3Ⅱ/LC3Ⅰ蛋白表达量,升高P62蛋白的表达水平,降低OGD/R引起的线粒体自噬水平。由此可见,OGD/R处理能引起PC12细胞的线粒体功能紊乱、MAM结构改变及线粒体自噬增加,As-exo处理后能改善细胞的线粒体功能、减弱MAM的形成和降低线粒体自噬,从而具有预防缺血性脑卒中再灌注损伤的治疗潜力。

关键词：外泌体星形胶质细胞氧糖剥夺再灌注线粒体自噬线粒体相关内质网膜

2,3,7,8-Tetrachlorodibenzo-p-dioxin Promotes Proliferation of Astrocyte Cells via the Akt/STAT3/Cyclin D1 Pathway

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Biomedical and Environmental Sciences 2019年第4期32卷 281-290页

作者： wu chang Yue YIN Kai Zhi ZHANG Yan JIAO Man ZHAO Xin Yuan wu Qi Yun Medical Colledge Nantong University Department of Nutrition and Food Hygiene School of Public HealthNantong University Xishan District Center for Disease Control and Preventive Department of Occupational Medicine and Environmental Toxicology School of Public HealthNantong University

Objective The compound 2,3,7,8-tetrachlorodibenzo-p-dioxin(TCDD), a persistent organic pollutant, is harmful to the nervous system, but its effects on the brain are still unclear. This study aimed to investigate the effects of TCDD on astrocytes proliferation and underlying molecular mechanism. Methods The cell proliferation was measured by EdU-based proliferation assay and PI staining by flow cytometry. Protein expression levels were detected by Western blotting. Immunofluorescence, cytoplasmic and nuclear fractions separation were used to assess the distribution of signal transducer and activator of transcription 3(STAT3). Results C6 cells treated with 10 and 50 nmol/L TCDD for 24 h showed significant promotion of the proliferation of. The exposure to TCDD resulted in the upregulation in the expression levels of phosphorylated protein kinase B(p-Akt), phosphorylated STAT3, and cyclin D1 in a dose-and time-dependent manner. The inhibition of Akt expression with LY294002 or STAT3 expression with AG490 abolished the TCDD-induced cyclin D1 upregulation and cell proliferation. Furthermore, LY294002 suppressed the activation of STAT3. Finally, TCDD promoted the translocation of STAT3 from the cytoplasm to the nucleus, and LY294002 treatment blocked this effect. Conclusion TCDD exposure promotes the proliferation of astrocyte cells via the Akt/STAT3/cyclin D1 pathway, leading to astrogliosis.

关键词： 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) Akt STAT3 Cyclin D1 Proliferation Astrocytes

Determination of L-Cystine by a New Sensitive Cucurbit[7]uril/palmatine Probe

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Chinese Journal of Chemistry 2011年第6期29卷 1268-1272页

作者： Yang, Jiyuan Du, Liming wu, Hao chang, Yinxia Li, changfeng Analytical and Testing Center Shanxi Normal University Linfen Shanxi 041004 China

In the presence of cucurbit[7]uril （CB[7]）, the CB[7] could react with palmatine, which served as a sensitive fluorescence probe, to form host-guest stable complexes and the fluorescence intensity of the complexes was greatly enhanced. The fluorescence intensity decreased linearly with an increasing number of L-cystine in the inclusion system. The experimental results show that there exists a competition between L-cystine and palmatine for the CB[7] hydrophobic cavity and L-cystine occupies the space of CB[7] cavity, leading palmatine molecules to be forced to reside in the aqueous environment. Based on the fluorescence quenching of the CB[7]/palmatine complexes resulting from complex formation between CB[7] and L-cystine, a spectrofluorimetric method for the determination of L-cystine in aqueous solution in the presence of CB[7] was developed. The linear relationship between the corresponding values of the fluorescence quenching AF and L-cystine concentration was obtained in the range of 6.0 to 1.5 × 10^3 ngomL l, with a correlation coefficient （r） of 0.9996. The detection limit was 2.0 ng·mL -1. The application of the present method to the determination of L-cystine in tablets gave satisfactory results. This paper also discussed the mechanism of the fluorescence indicator probe.

关键词： fluorescence spectroscopy host-guest systems trace analysis L-cystine

Synthesis and Crystal Structure of a Three-dimensional Cd(II) Coordination Polymer [Cd(μ_(1,3)-SCN)(μ_3-pco)]_n(pco=Pyrazine-2-carboxylate 4-oxide Anion)

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Chinese Journal of Structural Chemistry 2006年第8期25卷 937-939页

作者： SHI Jing-Min XU Hong-Kun wu chang-Ju LIU Lian-Dong Department of Chemistry Shandong Normal University Jinan 250014 China

The three-dimensional complex [Cd（μ1,3-SCN）（μ3-pco）]n has been synthesized with μ1,3-SCN^- and pco as mixed bridged ligands. The crystal belongs to monoclinic, space group P21/n with a = 10.3777（16）, b = 6.2592（9）, c = 13.150（2） A, β= 97.317（2）°, V= 847.2（2） A^3, Z= 4, C6H3CdN3O3S, Mr = 309.575, Dc = 2.427 g/cm^3, F（000） = 592 and μ = 2.804 mm^-1. The structure was refined to R = 0.0255 and wR = 0.0550 for 1712 observed reflections （1 〉 2σ（I））. In the crystal the Cd（Ⅱ） ions are coordinated by μ1,3-SCN^- and μ3-pco bridge ligands to form a three-dimensional structure.

关键词： synthesis crystal structure cadmium(Ⅱ) complex thiocyanate aromatic N-oxide

Charge transport in organic semiconductors: From incoherent to coherent

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Chinese Science Bulletin 2013年第22期58卷 2669-2676页

作者： YAO Yao SI Wei YANG WenChao wu chang-Qin State Key Laboratory of Surface Physics Department of PhysicsFudan University

Quantum decoherence in organic charge transport is a complicated but crucial topic. In this paper, several theoretical approaches corresponding to it, from incoherent to coherent, are comprehensively reviewed. We mainly focus on the physical insight provided by each theory and extent of its validity. The aim of this review is to clarify some contentious issues and elaborate on the promising perspectives provided by different approaches. The device model approaches based on both continuous and discretized treatments of the transporting layer will be first discussed. The prominent focus of this review will be devoted to the dynamic disorder model and its variants considering that it is the most promising approach to tackle charge transport problems in organic materials. We will also address other theories such as the variational method.

关键词：电荷传输有机半导体离散化处理相干效应设备型号有机材料洞察力变分法