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肺腺癌组织B细胞中乳清酸性蛋白4-二硫键核心结构域2(WFDC2)的表达与患者生存率的相关性分析 被引量:7
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作者 张浩轩 陆进 +1 位作者 杨月 王黎源 《细胞与分子免疫学杂志》 CAS CSCD 北大核心 2019年第5期425-433,共9页
目的探讨乳清酸性蛋白4-二硫键核心结构域2/人附睾蛋白4(WFDC2/HE4)在肺腺癌(LUAD)中的表达及临床意义。方法分别利用BioGPS数据库、 GEPIA数据库、 Oncomine数据库和Kaplan-Meier Plotter数据库分析WFDC2在正常肺组织与LUAD中的表达及... 目的探讨乳清酸性蛋白4-二硫键核心结构域2/人附睾蛋白4(WFDC2/HE4)在肺腺癌(LUAD)中的表达及临床意义。方法分别利用BioGPS数据库、 GEPIA数据库、 Oncomine数据库和Kaplan-Meier Plotter数据库分析WFDC2在正常肺组织与LUAD中的表达及对LUAD患者生存预后的意义;利用癌症细胞系百科全书(CCLE)分析WFDC2在癌组织T细胞与B细胞中的表达。利用String数据库分析WFDC2相关基因及其基因本体(GO)功能注释和京都基因和基因组百科全书(KEGG)通路富集。利用cBioPortal数据库分析WFDC2相关基因在LUAD中的共表达关系、相关性和显著性。肿瘤免疫评估资源(TIMER)数据库用于分析WFDC2在免疫浸润物中的表达及对LUAD患者生存预后的意义。结果BioGPS数据库分析结果显示WFDC2在正常肺组织中低表达,而在人体正常组织的T细胞和B细胞中不表达。GEPIA数据库分析结果显示WFDC2在LUAD组织中较正常肺组织高表达。Oncomine数据库检索出WFDC2差异表达的结果414项。其中, WFDC2表达增高19项, LUAD有4项;WFDC2表达降低15项, LUAD有1项;对符合设定条件的4项高表达研究结果进行Meta分析,发现WFDC2在LUAD组织中呈高表达状态;Kaplan-Meier Plotter数据库分析结果显示WFDC2高表达组的LUAD患者总体生存(OS)较低表达组显著延长。CCLE分析结果显示WFDC2在癌组织T细胞和B细胞中的表达较正常组织显著增高。String数据库分析显示与WFDC2相关联的基因30个,参与4条信号通路, GO注释分类结果表明富集于8类细胞学组分、4类分子功能和27类生物学过程。cBioPortal数据库分析显示分泌性白细胞蛋白酶抑制物(SLPI)与WFDC2在LUAD中相关性和差异最显著。TIMER数据库分析显示在免疫微环境中高表达WFDC2的B细胞可显著延长LUAD患者1年、3年、5年和10年生存预后时间。结论 WFDC2在LUAD组织中高表达,具有抗肿瘤免疫抑制作用,可显著延长LUAD患者的OS,可作为LUAD临床预后的候选标志物。 展开更多
关键词 乳清酸性蛋白4-二硫键核心结构域2/人附睾蛋白4(WFDC2/HE4) 肺腺癌 肿瘤 总体生存 生物信息学
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含1,4-萘基结构的聚芳醚酮的合成与表征
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作者 徐海云 陈永红 +1 位作者 崔明 胡荣华 《合成化学》 CAS CSCD 2003年第2期134-137,146,共5页
以无水AlCl3为催化剂 ,N 甲基吡咯烷酮为助剂 ,ClCH2 CH2 Cl为溶剂 ,将一种含萘环的新芳醚单体——— 4 ,4’ 二 (α 萘氧基 )二苯酮 (DNBP)分别与对苯二甲酰氯、间苯二甲酰氯、2 ,5 二氯对苯二甲酰氯等芳二酰氯通过低温溶液亲电共缩... 以无水AlCl3为催化剂 ,N 甲基吡咯烷酮为助剂 ,ClCH2 CH2 Cl为溶剂 ,将一种含萘环的新芳醚单体——— 4 ,4’ 二 (α 萘氧基 )二苯酮 (DNBP)分别与对苯二甲酰氯、间苯二甲酰氯、2 ,5 二氯对苯二甲酰氯等芳二酰氯通过低温溶液亲电共缩聚反应合成了 6种主链含 1,4 萘基结构的新型聚芳醚酮醚酮酮无规共聚物。考察了溶剂体系、反应温度、反应时间、单体摩尔浓度等聚合反应条件对聚合物分子量的影响 ,并用对数比浓粘度 (ηinh) ,IR ,DSC ,TG和WAXD等方法对其进行了分析表征。结果表明 :它们均为非晶态聚合物 ,有较高的玻璃化温度和优良的耐热性 ,可溶于一些强极性非质子溶剂中。并以CHCl3为溶剂 ,甲醇和正己烷为沉降剂用浊度滴定法测定了上述 6种聚合物的溶度参数 (δ)。 展开更多
关键词 聚芳醚酮 合成 表征 l 4-萘基结构 工程塑料
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4-几何结构下测试线段相交性快速算法
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作者 王洪申 强会英 《微电子学与计算机》 CSCD 北大核心 2005年第11期181-182,185,共3页
提出了一种4-几何结构下两线段相交性测试的快速算法。算法根据4-几何结构的特点,主要以加减运算和快速判断代替了过多使用乘法的传统判断线段相交性的算法,从而加快了算法速度。实验证明算法的性能良好。
关键词 线段相交性测试 4-几何结构 交点 算法
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小鼠VEGFR2胞外1-4IgG样结构域的原核表达、纯化及活性鉴定
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作者 王伟 殷小涛 +4 位作者 李云奇 田仁礼 阎瑾琦 高江平 于继云 《南方医科大学学报》 CAS CSCD 北大核心 2013年第1期13-17,共5页
目的获得小鼠血管内皮生长因子Ⅱ型受体(mVEGFR2)胞外1-4IgG样结构域融合蛋白并验证其免疫原性及生物活性。方法利用RT-PCR法从孕龄14 d的Balb/c小鼠胚胎组织中扩增mVEGFR2D1-4基因,测序正确后将其克隆至原核表达载体pET-42a,构建重组质... 目的获得小鼠血管内皮生长因子Ⅱ型受体(mVEGFR2)胞外1-4IgG样结构域融合蛋白并验证其免疫原性及生物活性。方法利用RT-PCR法从孕龄14 d的Balb/c小鼠胚胎组织中扩增mVEGFR2D1-4基因,测序正确后将其克隆至原核表达载体pET-42a,构建重组质粒pET-42a-mVEGFR2D1-4。将其转化至大肠杆菌BL21(DE3)中IPTG诱导表达,经SDS-PAGE分析,目的蛋白用Western blotting鉴定后,亲和层析法纯化融合蛋白,ELISA法检测纯化蛋白的抗原活性,并通过体外细胞培养检测该融合蛋白对血管内皮生长因子(VEGF)促人脐静脉内皮细胞(HUVEC)增殖的阻断作用。结果测序结果证实成功扩增出目的基因mVEGFR2D1-4;酶切和测序结果证实pET-42a-mVEGFR2D1-4原核表达载体构建成功;转化后可以成功诱导并纯化出大小与预期一致的蛋白;Western blotting证实纯化的蛋白能与特异性抗体发生反应;ELISA检测显示纯化后的mVEGFR2D1-4融合蛋白具有免疫原性,并且体外细胞培养试验证实其能阻断VEGF对HUVEC的促增殖作用。结论成功获得mVEGFR2D1-4/GST融合蛋白,该蛋白具有良好的免疫原性及生物活性,为进一步研究以VEGFR2为靶点的抗肿瘤主动免疫治疗奠定了基础。 展开更多
关键词 血管内皮生长因子Ⅱ型受体 1-4IgG样结构 原核表达 蛋白纯化
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超高效液相色谱-四级杆飞行时间质谱法同时检验全血中5种4-取代卡西酮类结构类似物 被引量:4
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作者 徐琳 倪春芳 +3 位作者 何洪源 赵海波 刘静 顾海硕 《科学技术与工程》 北大核心 2021年第6期2172-2178,共7页
为实现对同位置不同取代基团的卡西酮类结构类似物的准确分析,建立了超高效液相色谱-四级杆飞行时间串联质谱法(UPLC-QTOF-MS)检验全血中4-甲基甲卡西酮(4-methylmethcathi-none,4-MMC)、4-氟甲卡西酮[1-(4-fluoroph-enyl)-2-methylamin... 为实现对同位置不同取代基团的卡西酮类结构类似物的准确分析,建立了超高效液相色谱-四级杆飞行时间串联质谱法(UPLC-QTOF-MS)检验全血中4-甲基甲卡西酮(4-methylmethcathi-none,4-MMC)、4-氟甲卡西酮[1-(4-fluoroph-enyl)-2-methylaminopropan-1-one,4-FMC]、4-氯甲卡西酮[1-(4-chlorophenyl)-2-(methylami-no)propan-1-one,4-CMC]、4-溴甲卡西酮[1-(4-bromophenyl)-2-methylaminopropan-1-one,4-BMC]、4-甲氧基甲卡西酮[1-(4-methoxyphe-nyl)-2-methylaminopropan-1-one,Methedrone]5种同位置不同取代基团的卡西酮类结构类似物。前处理选用沉淀蛋白法:室温下,将不同浓度混标毒品与全血的混合物震荡1 min,在12000 r/min转速、温度为5℃的条件下离心7 min。离心结束之后,取上清液待用。采用ACQUITY UPLC BEH C18色谱柱(2.1 mm×100 mm,1.7μm)分离,以0.1%甲酸水和0.1%甲酸乙腈为流动相进行梯度洗脱,电喷雾电离正离子扫描多反映检测模式。5种毒品检出限(信噪比S/N≥3)在0.5~1 ng/mL,定量限(S/N≥10)在1~2 ng/mL,基质效应为72.97%~101.44%,回收率为98.18%~119.77%,日内及日间精密度RSD≤9.95%。本文方法快速、准确,可实现全血中5种4-取代卡西酮类结构类似物定性定量分析,满足实际检验工作需要。 展开更多
关键词 超高效液相色谱-四级杆飞行时间质谱 沉淀蛋白 全血 4-取代卡西酮类结构类似物
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丙型肝炎病毒NS3-4A蛋白对MMP-9及天然免疫的影响
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作者 逯艳艳 孔鑫磊 +1 位作者 刘芝兰 马颖才 《广东医学》 CAS 北大核心 2015年第20期3132-3136,共5页
目的探讨HCV编码的NS3-4A蛋白对MMP-9表达的调节作用。方法利用Primer Premier5.0软件设计相关引物,构建在相应的载体上;使用PCR扩增目的基因;PCR产物以及双酶切产物的胶回收;冷氯化钙法制备感受态细胞;YC法转化感受态细胞;进行细胞培... 目的探讨HCV编码的NS3-4A蛋白对MMP-9表达的调节作用。方法利用Primer Premier5.0软件设计相关引物,构建在相应的载体上;使用PCR扩增目的基因;PCR产物以及双酶切产物的胶回收;冷氯化钙法制备感受态细胞;YC法转化感受态细胞;进行细胞培养基的配制;之后进行RT-PCR反应。结果在Huh7.5.1细胞内,内源性的MMP-9可以被NS3-4A蛋白上调表达;转染了p CMV-tag2A-NS3-4A质粒的Huh7.5.1细胞与未转染的细胞相比,其内源性MMP-9的表达可以明显被NS3-4A蛋白上调。在Huh7.5.1细胞中,IFN-α可以增促进MMP-9基因mRNA的表达,且这种增强作用呈现出剂量依赖性;在转染了p CMVtag2B-MMP-9质粒的Huh7.5.1细胞中,其内源性IFN-α及其受体IFNAR1和IFNAR2的表达可以被MMP-9蛋白抑制,且对IFN-α及IFNAR1的抑制作用具有较明显的剂量依赖性;向转染了p CMV-tag2B质粒的Huh7.5.1细胞中加入IFN-α可以上调其内源性的PKR和OAS2的表达,而MMP-9又可以抑制这些基因的表达,这反过来也说明MMP-9可以抑制IFN-α及其受体IFNAR1和IFNAR2的表达,进而抑制IFN-α下游PKR和OAS2的表达;IFN-α可以上调Huh7.5.1细胞中内源性的PKR和OAS2的表达,而MMP-9又可以抑制这些基因的表达,这与之前mRNA水平的检测结果相一致。结论在HCV的感染过程中,NS3-4A蛋白可以促进细胞内源性IFN-α的表达,而IFN-α的高表达又会导致MMP-9的高表达,MMP-9反过来又会抑制IFN-α及其受体IFNAR1和IFNAR2的表达水平,进而抑制IFN-α下游的PKR及OAS2基因。 展开更多
关键词 丙型肝炎病毒 基质金属蛋白酶-9 结构蛋白NS3-4A Α干扰素
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Microstructure and corrosion resistance of sputtered TiN coatings on surface of Zr-4 alloy 被引量:1
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作者 LIAO Bang-liang MA Jian-guang +6 位作者 ZHU Wei-hua ZHU Hong-mei YANG Kai LIU Yan-hong LI Huai-lin WANG Xiao-jing WANG Xin-lin 《Journal of Chongqing University》 CAS 2018年第1期17-26,共10页
To improve the oxidation resistance and corrosion resistance of Zr-4 alloy, titanium nitride (TIN) coatings were prepared on the Zr-4 alloy with a TiN ceramic target with different ratios of N2. Microstructure and h... To improve the oxidation resistance and corrosion resistance of Zr-4 alloy, titanium nitride (TIN) coatings were prepared on the Zr-4 alloy with a TiN ceramic target with different ratios of N2. Microstructure and high-temperature properties of the TiN coated samples were studied by scanning electron microscopy (SEM), energy dispersive spectrometer (EDS), X-ray diffraction meter (XRD), X-ray photoelectron spectroscopy (XPS), heat treatment furnace and autoclaves, respectively. The x value of the TiN coatings (TiN) ranges from 0.96 to 1.33. After the introduction of N2, TiN coating exhibits a weak (200) plane and a preferred (111) orientation. The coating prepared with an N2 flow ratio of 15% shows an optimal oxidation resistance in the atmospheric environment at 800 ℃. In either 1 200 ℃ steam environment for one hour, or deionized water at 360 ℃ and a pressure of 18.6 Mpa for 16 d, the opitimized TiN coated samples have no delamination or spallation; and the gains in the masses of samples are much smaller than Zr-4 alloy. These results demonstrate the effectiveness of the optimized TiN coating as the protective coating on the Zr-4 alloy under extreme conditons. 展开更多
关键词 Zr-4 alloy magnetron sputtering TiN coating high temperature oxidation resistance corrosion resistance
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阻断TIM-4分子对M1/M2型巨噬细胞极化及同种异体免疫排斥反应的影响 被引量:1
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作者 陶佳玲 樊慧敏 +2 位作者 唐涛 邵启祥 丁庆 《江苏大学学报(医学版)》 CAS 2020年第6期520-525,共6页
目的:运用特异性单克隆抗体阻断抗原T细胞免疫球蛋白及黏蛋白结构域蛋白-4(T-cell immunoglobulin and mucin domain containing protein-4,TIM-4),探讨其对巨噬细胞(M1/M2)极化及同种异体免疫排斥反应的影响。方法:构建同种异体免疫排... 目的:运用特异性单克隆抗体阻断抗原T细胞免疫球蛋白及黏蛋白结构域蛋白-4(T-cell immunoglobulin and mucin domain containing protein-4,TIM-4),探讨其对巨噬细胞(M1/M2)极化及同种异体免疫排斥反应的影响。方法:构建同种异体免疫排斥模型,将BALB/c小鼠脾细胞悬液注入C57BL/6小鼠腹腔,分为同型对照组(n=6)和抗TIM-4组(n=6);分别腹腔注射同型对照免疫球蛋白和抗TIM-4单克隆抗体,300μg/只;第5天,重复注射1次;第10天,处死两组小鼠,采用流式细胞术检测受体鼠脾和腹腔中M1和M2型巨噬细胞百分比;用实时荧光定量PCR法检测受体鼠脾和腹腔细胞中微小RNA-21(miR-21)、IL-10、p40、p35和EB病毒诱导基因3(Epstein-Barr virus-induced gene-3,EBi-3)等mRNA表达水平。结果:在脾细胞中,与同型对照组相比,抗TIM-4组M1和M2型巨噬细胞百分比、miR-21和p40 mRNA表达水平无明显变化(P均>0.05),但IL-10和p35 mRNA表达水平明显升高(P均<0.05),EBi-3 mRNA表达水平明显下降(P<0.05);在腹腔中,与同型对照组相比,抗TIM-4组M1型巨噬细胞百分比和p35 mRNA表达水平无明显变化(P均>0.05),而M2型巨噬细胞百分比、IL-10、p40和EBi-3 mRNA表达水平均显著升高(P均<0.05),miR-21表达水平显著降低(P<0.05)。结论:阻断TIM-4分子促进小鼠腹腔M2增殖分化,上调脾和腹腔细胞中抑炎因子和促炎因子mRNA表达,减轻同种异体免疫排斥反应。 展开更多
关键词 T细胞免疫球蛋白及黏蛋白结构域蛋白-4 M1/M2型巨噬细胞 微小RNA-21 细胞因子 极化 免疫排斥
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Visible-light-induced NiCo_(2)O_(4)@Co_(3)O_(4) core/shell heterojunction photocatalysts for efficient removal of organic dyes 被引量:2
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作者 WANG Huan-wei FANG Xin +3 位作者 WAN Yu-chi ZHAN Jing WANG Zhi-jian LIU Hua 《Journal of Central South University》 SCIE EI CAS CSCD 2021年第10期3040-3049,共10页
Semiconductor photocatalysis has been considered as a potential technology for the removal of organic dyes from wastewater.The development of photocatalysts with high stability and strong catalytic activity is the mos... Semiconductor photocatalysis has been considered as a potential technology for the removal of organic dyes from wastewater.The development of photocatalysts with high stability and strong catalytic activity is the most important in application.Visible-light-induced NiCo_(2)O_(4)@Co_(3)O_(4) core/shell heterojunctions were synthesized via a sol-gel method in this paper.Compared to bare NiCo_(2)O_(4) and Co_(3)O_(4),NiCo_(2)O_(4)@Co_(3)O_(4) showed a remarkably enhanced removal rate towards congo red(CR)degradation with 98.4%of the removal rate to CR at 120 min under irradiation.The excellent performance of NiCo_(2)O_(4)@Co_(3)O_(4) benefits from the effective separation of photogenerated electron-holes by forming a heterojunction,and the rapid transfer efficiency of photo-generated charge carriers results from the core/shell architectures.A mechanism that NiCo_(2)O_(4)@Co_(3)O_(4) degrades CR to harmless inorganic substances by h^(+),•O-2 and•OH during the photocatalytic process was proposed. 展开更多
关键词 visible-light-inducment NiCo_(2)O_(4)@Co_(3)O_(4) HETEROJUNCTION core/shell architectures
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Hierarchical porous Co_(3)O_(4) spheres fabricated by modified solvothermal method as anode material in Li-ion batteries 被引量:1
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作者 Yan FENG Cai-yu CAO +3 位作者 Jing ZENG Ri-chu WANG Chao-qun PENG Xiao-feng WANG 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2022年第4期1253-1260,共8页
Hierarchical porous Co_(3)O_(4)spheres were synthesized by a solvothermal method followed by high-temperature calcination.XRD,SEM,TEM and electrochemical tests were used to study the structure and performance of the h... Hierarchical porous Co_(3)O_(4)spheres were synthesized by a solvothermal method followed by high-temperature calcination.XRD,SEM,TEM and electrochemical tests were used to study the structure and performance of the hierarchical porous Co_(3)O_(4)spheres.The results show that the Co_(3)O_(4)synthesized at a calcination temperature of 700°C(Co_(3)O_(4)-700)is micro-sized spheres(1-2μm)consisting of plentiful nanoparticles(50-200 nm)and numerous pores(~100 nm).Due to its numerous porous morphology,the Co_(3)O_(4)-700 anode exhibits the highest cycling performance with excellent reversible discharge and charge specific capacities of 745 and 755 m A·h/g at the current density of 100 m A/g after 100 charge-discharge cycles,respectively. 展开更多
关键词 Co_(3)O_(4) lithium-ion batteries porous structure SPHERES CALCINATION
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Bio‐inspired nanostructured g-C_(3)N_(4)-based photocatalysts:A comprehensive review 被引量:3
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作者 Bo Lin Mengyang Xia +3 位作者 Baorong Xu Ben Chong Zihao Chen Guidong Yang 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 2022年第8期2141-2172,共32页
As a new organic conjugated semiconductor,graphitic carbon nitride(g-C_(3)N_(4))is emerging as a fascinating material for various photocatalytic applications due to its adjustable electronic structure,outstanding ther... As a new organic conjugated semiconductor,graphitic carbon nitride(g-C_(3)N_(4))is emerging as a fascinating material for various photocatalytic applications due to its adjustable electronic structure,outstanding thermal endurance,appealing chemical stability,low cost,and environmental friendliness.Nevertheless,unmodified bulk g-C_(3)N_(4) possesses some intrinsic limitations related to poor crystallinity,marginal visible-light harvesting,easy recombination of charge pairs,small surface area,and slow charge migration,which give rise to the low quantum efficiency of photocatalytic reactions.One efficient strategy to overcome these shortcomings is the manipulation of the microstructures of g-C_(3)N_(4).Other than the traditional structure control,mimicking the structures of creatures in nature to design and construct bio-inspired structures is a promising approach to improve the photocatalytic performance of g-C_(3)N_(4) and even g-C_(3)N_(4)-based systems.This review summarizes the recent advances of the traditional structure-control of g-C_(3)N_(4)-based systems,and bio-inspired synthesis of g-C_(3)N_(4)-based systems from two aspects of structural bionics and functional bionics.Furthermore,the fundamentals of bio-inspired design and fabrication of g-C_(3)N_(4)-based systems are introduced in detail.Additionally,the different theoretical calculations,diverse photocatalytic applications and various modification strategies of bio-inspired structured g-C_(3)N_(4)-based systems are recapped.We believe that this work will be a guiding star for future research in the new field of biomimetic photocatalysis. 展开更多
关键词 g-C_(3)N_(4)-based system Bio-inspired design Structure control Biomimetic photocatalysis Reaction mechanism
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Synthesis and Structure of [Cu(OH)_2(H_2O)_2(4-C_5H_4N-COOH)_2] 被引量:1
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作者 ZHONG Zhao-En SUN Dao-Feng 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2001年第6期478-480,共3页
The hydrothermal reaction of isonicotinic acid (4-C5H4N-COOH), Cu(ClO4)(2). 6H(2)O and water at 170 degreesC gave the title compound, [Cu(OH)(2)(H2O)(2)(4-C5H4N-COOH)(2)] (1), which was analyzed by single-crystal X-ra... The hydrothermal reaction of isonicotinic acid (4-C5H4N-COOH), Cu(ClO4)(2). 6H(2)O and water at 170 degreesC gave the title compound, [Cu(OH)(2)(H2O)(2)(4-C5H4N-COOH)(2)] (1), which was analyzed by single-crystal X-ray diffraction, The complex crystallizes in triclinic space group PY with unit cell parameters: a = 6.337(2), b = 6.894(3), c = 9.178(3). alpha = 99.40(3), beta = 105.26(3), gamma 108.17(5)degrees, V = 354.1(2)Angstrom (3), Z = 1, C12H16CuN2O8, M-r = 379.81, D-c = 1.791 Mg/m(3), F(000) 197, mu (MoK alpha) = 1.589 mm(-1). The final R and wR are 0.068 and 0.170 for 1249 observed reflections with I greater than or equal to2 sigma (I). The central copper ion is in a distorted octahedron geometry completed by two nitrogen atoms from carboxylic ligand, two oxygen atoms from hydroxyl groups and two oxygen atoms from coordinated water molecules. The intermolecular hydrogen bonding leads to the formation of a three-dimensional supramolecular structure. 展开更多
关键词 hydrothermal reaction copper complex intermolecular hydrogen bonding
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磷酸酯钕系催化剂合成高顺式丁二烯-异戊二烯共聚物 被引量:8
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作者 孔春丽 胡雁鸣 +2 位作者 李杨 史正海 张学全 《合成橡胶工业》 CAS CSCD 北大核心 2012年第5期356-360,共5页
以2-乙基己基磷酸单2-乙基己基酯钕盐(简称Nd)/氢化二异丁基铝(简称Al)/一氯二乙基铝(简称Cl)为催化剂进行丁二烯(Bd)和异戊二烯(Ip)共聚合,考察了反应条件对聚合反应的影响,并对产物结构进行了表征。结果表明,Nd/Al/Cl催化体系具有单... 以2-乙基己基磷酸单2-乙基己基酯钕盐(简称Nd)/氢化二异丁基铝(简称Al)/一氯二乙基铝(简称Cl)为催化剂进行丁二烯(Bd)和异戊二烯(Ip)共聚合,考察了反应条件对聚合反应的影响,并对产物结构进行了表征。结果表明,Nd/Al/Cl催化体系具有单一活性中心,所合成的Bd-Ip共聚物为无规共聚物。催化剂制备时Ip用量越大,聚合活性越大,共聚物的分子量分布越窄。在c(Ip)/c(Nd)为50、c(Al)/c(Nd)为10、c(Cl)/c(Nd)为1.0,于60℃陈化2 h制备催化剂,然后以己烷作溶剂,在c(Nd)/c(Bd)为6.8×10-4、Bd/Ip(摩尔比)为1/1的条件下,于50℃聚合8 h,所得Bd-Ip共聚物具有高顺式结构,聚丁二烯链段的顺式-1,4-结构摩尔分数为95.2%,聚异戊二烯链段的顺式-1,4-结构摩尔分数为97.4%,且分子量分布较窄,为2.45。 展开更多
关键词 丁二烯-异戊二烯共聚物 磷酸酯钕催化剂 顺式-1 4-结构 分子量分布
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Crystal Structure of 3-(4-nitro-) phenylsulfonyloxyisothiazole NO_2C_6H_4SO_3C_3H_2NS
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作者 杨小平 王宏根 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 1998年第2期81-84,共4页
C9H6N2O5S2 is monoclinic, space group P21/n, for 1278 observed reflections . The result indicates clearly the sul-fonylation takes place at oxygen. According to the data of bond lengths, the isothiazole ring displays ... C9H6N2O5S2 is monoclinic, space group P21/n, for 1278 observed reflections . The result indicates clearly the sul-fonylation takes place at oxygen. According to the data of bond lengths, the isothiazole ring displays aromaticity in some way. 展开更多
关键词 crystal structure ISOTHIAZOLE acyl migration
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Synthesis and Crystal Structure of ( Z)-4-( p- Bromophenylthio)-3-( p-nitrobenzoyloxy)-3-buten-2-one 被引量:1
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作者 刘继德 Tamariz,Jo 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 1999年第5期322-325,共4页
A new enone (CH 3CO C( p NO 2C 6H 4COO)=CH S C 6H 4( p Br) 5, C 17 H 12 NBrO 5S, M r =422.25) was synthesized and its crystal structure was determined by X ray diffraction method. The crystal belongs to the monoclinic... A new enone (CH 3CO C( p NO 2C 6H 4COO)=CH S C 6H 4( p Br) 5, C 17 H 12 NBrO 5S, M r =422.25) was synthesized and its crystal structure was determined by X ray diffraction method. The crystal belongs to the monoclinic system, space group P2 1/c with a=6.4121(9), b=12.804(1), c=20.998(2) , β=94.884(9)°, V=1717.1(3) 3, Z=4, D c =1.633 g/cm 3, μ (Mo Kα )=2.542 mm -1 , F( 000)=848. Final R =0.0428 and wR =0.0916 for 3335 reflections with I>2σ(I) . The title compound exists as Z isomer with p bromothiophenolate and o nitrobenzoate groups cis arranged around asymmetrical centre. This observation suggests that the substitution of thiophenolate for bromine is a stereoselective step. 展开更多
关键词 ENONE crystal structure CONFORMATION
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Crystal Structure of 2-(4-Fluorophenylamino)-2-thiomethyl acetophenone
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作者 ZOU Jian-Ping LIU Xian-Jun +1 位作者 ZENG Run--Sheng LU Zhong-E (Department of Chemistry,Suzhou University,Suzhou,215006) 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 1997年第1期56-58,共3页
The title compound 2-(4-fluorophenylamino)-2-thiomethyl acetophe-none (C15H14FNOS, M. = 275. 34 ) was synthesized by the reaction of 2-hydroxy-2-thiomethyl acetohenone (abenzoylhemithioacetal ) with 4-fluoroaniline. T... The title compound 2-(4-fluorophenylamino)-2-thiomethyl acetophe-none (C15H14FNOS, M. = 275. 34 ) was synthesized by the reaction of 2-hydroxy-2-thiomethyl acetohenone (abenzoylhemithioacetal ) with 4-fluoroaniline. The crystal ismonoclinic, space group P21/n. with unit cell constants a = 12. 434 (4 ), b = 6. 00l2(6), c=l8. 49l(2) A, β=100. 87(l)° Z = 4, V = 1355. O(5) A, D'= 1. 350g/cm3, μ(MoKa) = 2. 41 cm-l, F(000) = 576, R=0. 029, Rw.= 0. 041 for 14l2 ob-served reflections (I> 3σ(I) ). X-ray analysis reveals that the dihedral angle betweenplane l (C(l)~C(6), F, N ) and plane 2 (C(8)~C(14), O ) is 4. l8° and theC(7) -S bond is longer than normal single C-S bond. 展开更多
关键词 crystal structure 2-fluorophenylamino-2-thiomethyl acetophenone
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Synthesis and Crystal Structure of 4-(2- Chlorophenyl)-5-cyano-3-methyl-6-oxo-1- phenyl-4,5,6,7-tetrahydropyrazolo[3,4-b] Pyridine under Microwave Irradiation
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作者 朱松磊 屠树江 +4 位作者 李团结 邹翔 章晓镜 纪顺俊 张勇 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2004年第11期1222-1225,共4页
The title compound (C20H15ClN4O, Mr = 362.81) was synthesized by the reaction of ethyl 2-cyano-3-(2-chlorophenyl)-1-acylate with 5-amino-3-methyl-1-phenylpyrazole under microwave irradiation and its structure was dete... The title compound (C20H15ClN4O, Mr = 362.81) was synthesized by the reaction of ethyl 2-cyano-3-(2-chlorophenyl)-1-acylate with 5-amino-3-methyl-1-phenylpyrazole under microwave irradiation and its structure was determined by single-crystal X-ray diffraction. The crystal is of monoclinic, space group P21/n with a = 8.8192(19), b = 15.976(3), c = 13.094(3) ? = 103.074(4), V = 1797.1(7) ?, Z = 4, Dc = 1.341 g/cm3, = 0.229 mm-1, F(000) = 752, R = 0.0632 and wR = 0.1278. X-ray analysis reveals that the pyridine ring adopts an envelope conformation. The dihedral angle between the pyrazole and pyridine planes is 2.19, and inter- molecular hydrogen bonds are also observed in the molecule. 展开更多
关键词 AMINOPYRAZOLE PYRAZOLOPYRIDINE crystal structure microwave irradiation
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Hydrothermal Synthesis and Crystal Structure of [(CH_3CH_2)_4N]_4[(La_(12)(OH)_(12)MoO_(29) )], A Novel Cluster Compound with a MoO_5 Hexahedron Center Surrounded by La-O Octahedron
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作者 HUChang-wen HUANGWei-tong +6 位作者 ZHANGHong WANGXiu-li LIYang-guang DUANGLi-ying LANYang WANGLi WANGEn-bo 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2003年第2期132-134,共3页
A novel compound [(CH 3CH 2) 4N] 4[(La 12 (OH) 12 MoO 29 )] was synthesized by hydrothermal reaction. The single crystal X ray diffraction shows that the compound crystallized in the monoclinic space group C2/c ; a =2... A novel compound [(CH 3CH 2) 4N] 4[(La 12 (OH) 12 MoO 29 )] was synthesized by hydrothermal reaction. The single crystal X ray diffraction shows that the compound crystallized in the monoclinic space group C2/c ; a =2 5729(4) nm, b =1 4318(1) nm, c =2 1217(4) nm, β =111 56(1)°, V =6 8235(7) nm 3, Z =4, R =0 0751. The basic building blocks of the crystal structure included one MoO 5 hexahedron and twelve LaO 6 octahedra which shared a common edge to form a [(La 12 (OH) 12 MoO 29 )] 4- unit. These units were held together by the [(CH 3CH 2) 4N] + ions. 展开更多
关键词 Hydrothermal synthesis Layer Lanthanum Triclinic system
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Synthesis and Crystal Structure of 2-[(4-Methoxy- 6-methylthio-2-pyrimidinyl)aminocarbonyl- aminosulfonyl] Benzoic Acid Methyl Ester
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作者 黄明智 王晓光 +2 位作者 毛春晖 黄路 宋海斌 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2004年第7期743-746,共4页
The title compound 2-[(4-methoxy-6-methylthio-2-pyrimidinyl)aminocarbonyl- aminosulfonyl]benzoic acid methyl ester (C15H16N4O6S2, Mr = 412.44) was obtained by the reaction of (4-methoxy-6-methylthio-2-pyrimidinyl)amin... The title compound 2-[(4-methoxy-6-methylthio-2-pyrimidinyl)aminocarbonyl- aminosulfonyl]benzoic acid methyl ester (C15H16N4O6S2, Mr = 412.44) was obtained by the reaction of (4-methoxy-6-methylthio-2-pyrimidinyl)amine with 2-methoxylcarbonylbenzene-sulfonylisocya- nate. The crystal is of monoclinic, space group P21/c with a =11.169(3), b = 9.508(3), c = 17.690(5) ? b = 91.593(5), Z = 4, V = 1877.9(10) 3, Dc = 1.459 g/cm3, F(000) = 856, m(MoKa) = 0.324 mm-1, R = 0.0690 and wR = 0.1368 for 3301 observed reflections (I > 2s(I)). The N(1)H…N(3) and N(2)H…O(4) hydrogen bonds can be observed. In the molecule the phenyl plane(I), pyrimi- din-2-yl-urea bridge plane(Ⅱ) and ester plane(Ⅲ) form three conjugated systems. 展开更多
关键词 crystal structure sulfonylurea herbicide 2-[(4-methoxy-6-methylthio-2- pyrimidinyl)aminocarbonylaminosulfonyl]benzoic acid methyl ester SYNTHESIS
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Crystal Structure of[La(NO_3)_3(12-crown-4)-(H_2O)](12-crown-4)
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作者 毛江高 金钟声 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 1994年第4期281-284,共4页
The crystal structure of crown ether-hydrogen bonded complex,[La(NO3)3 (12-crown-4) ( H2O)] (12-crown-4) has been determined by X-ray method. The title complex C16H34LaN3O18 (Mr=695. 5) crystallized in orthorhombic ... The crystal structure of crown ether-hydrogen bonded complex,[La(NO3)3 (12-crown-4) ( H2O)] (12-crown-4) has been determined by X-ray method. The title complex C16H34LaN3O18 (Mr=695. 5) crystallized in orthorhombic Pnma with a=23. 495(8), b=13. 603(5),c=8. 474(3); V=2706(1); Z=4 ; Dc=1. 71 g/cm3; F(000)=1408, μ=17. 0 cm-1 (MOKα). The final R=0. 052 and Rw= 0. 054(unit weight) for 1367 observed reflections. The La( Ⅲ) ion is 11-coordinated by three nitrale anions, four oxygen atoms from a crown ligand and one O atom of a water molecule. The other crown molecule is hydrogen bonded wilh the coordinated water molecule. The imposed mirror plane in the structure made both crown ligands and one of nitrate groups severely disordered. 展开更多
关键词 crystal structure lanthanum nitrate crown ether complex hydrogen bonding
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