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毛细管气相色谱法测定乳脂中的cis-9,trans-11-共轭亚油酸 被引量:18
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作者 王小静 沈向真 +2 位作者 韩航如 赵茹茜 陈杰 《色谱》 CAS CSCD 北大核心 2006年第6期645-647,共3页
建立了测定乳脂中cis-9,trans-11-共轭亚油酸(CLA)的毛细管气相色谱方法。样品经正己烷-异丙醇提取、甲醇-甲醇钠甲酯化后,进行气相色谱分析;采用程序升温,以保留时间定性,外标法定量。采用该方法测得共轭亚油酸的回收率为100.26%,相对... 建立了测定乳脂中cis-9,trans-11-共轭亚油酸(CLA)的毛细管气相色谱方法。样品经正己烷-异丙醇提取、甲醇-甲醇钠甲酯化后,进行气相色谱分析;采用程序升温,以保留时间定性,外标法定量。采用该方法测得共轭亚油酸的回收率为100.26%,相对标准偏差(RSD)为1.9%(n=6),检测限为1 mg/L。该方法样品用量少,前处理简单,建立的实验条件准确可靠,不仅可以用来测定cis-9,trans-11-CLA的含量,而且对于乳制品中所含的其他脂肪酸的分析测定也具有指导意义。 展开更多
关键词 毛细管气相色谱法 cis-9 trans-11-其轭业油酸 乳脂
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cis,trans-4-戊基环己基甲酸的合成及异构体转位 被引量:1
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作者 张越 牛玉环 +2 位作者 王荣耕 吴鹏程 马东来 《河北工业科技》 CAS 2006年第1期24-26,共3页
采用Ni5249P为催化剂,在水相碱性条件下,反应温度为175℃,反应压力为9MPa,加氢合成4-戊基环己基甲酸[m(civ):m(trans-)=75:253。在200-220℃进行异构体转位,可以使4-戊基环己基甲酸产物中m(cir):m(trans-)=2:98,trans... 采用Ni5249P为催化剂,在水相碱性条件下,反应温度为175℃,反应压力为9MPa,加氢合成4-戊基环己基甲酸[m(civ):m(trans-)=75:253。在200-220℃进行异构体转位,可以使4-戊基环己基甲酸产物中m(cir):m(trans-)=2:98,trans-4-戊基环己基甲酸收率为95%。 展开更多
关键词 cis trans-4-戊基环己基甲酸 trans-4-戊基环己基甲酸 异构化
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Synthesis of novel biscrown ethers with rigid cis/trans ethylene bridge
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作者 Jian Quan Fan La Sheng Jiang Min Zhang Na Wei Ya Hui Feng Shu Juan Han Hui Wang 《Chinese Chemical Letters》 SCIE CAS CSCD 2008年第5期513-517,共5页
Two novel biscrown ethers with rigid cis/trans ethylene linker were synthesized via Wittig reaction in high yield (about 80%). Their pure cisltrans-isomers were obtained by column chromatography separation. And thei... Two novel biscrown ethers with rigid cis/trans ethylene linker were synthesized via Wittig reaction in high yield (about 80%). Their pure cisltrans-isomers were obtained by column chromatography separation. And their structure/configuration was confirmed by ^1H NMR,^ 13C NMR, ESI mass spectrum, elemental analysis and UV-vis speca'a. 展开更多
关键词 Biscrown ethers SYNTHESIS Characterization cis/trans configuration
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trans/cis-[Co(en)_(2)Cl_(2)]Cl配合物的制备及其水解反应动力学常数测定——面向大一学生的基础型综合化学实验
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作者 欧阳小清 张春艳 +6 位作者 许振玲 潘蕊 吕银云 阮婵姿 翁玉华 董志强 任艳平 《大学化学》 CAS 2021年第4期173-179,共7页
为大一学生推荐一个基础型综合化学实验,即厦门大学为"化学拔尖计划"一年级学生个性化培养"量身定制"并经10年教学实践而逐步改进完善的实验项目——trans/cis-[Co(en)2Cl2]Cl配合物的制备及其水解反应动力学常数... 为大一学生推荐一个基础型综合化学实验,即厦门大学为"化学拔尖计划"一年级学生个性化培养"量身定制"并经10年教学实践而逐步改进完善的实验项目——trans/cis-[Co(en)2Cl2]Cl配合物的制备及其水解反应动力学常数测定。该实验项目涵盖了配合物顺-反异构体、晶体场分裂能、配合物的水解反应动力学等基础理论知识,以及顺-反异构体配合物的制备、光谱鉴定及不同介质中水解反应动力学研究等实验操作技能。通过系统的实验,使学生深入了解顺-反异构体配合物的制备、分离和鉴定方法以及配合物水解反应动力学研究的思路和方法等,有助于学生对结构决定性质的直观认识和深刻理解,有助于加强学生对理论与实验的深度融合以及对学生的分析、判断和批判性思维能力的培养。 展开更多
关键词 基础型综合实验 Co(Ⅲ)配合物 顺-反异构体 制备与鉴定 水解反应动力学
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“trans/cis-[Co(en)_(2)Cl_(2)]Cl配合物水解反应动力学常数测定”实验教学实施结果与探讨
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作者 张春艳 欧阳小清 +8 位作者 阮婵姿 吕银云 潘蕊 翁玉华 董志强 许振玲 彭淑女 李华敏 任艳平 《大学化学》 CAS 2021年第8期155-163,共9页
主要介绍厦门大学专门为"化学拔尖计划"学生个性化培养"量身定制"并经10年教学实践的"trans/cis-[Co(en)2Cl2]Cl配合物水解反应动力学常数测定"实验教学实施结果及探讨内容。引导学生以动力学实验数据和... 主要介绍厦门大学专门为"化学拔尖计划"学生个性化培养"量身定制"并经10年教学实践的"trans/cis-[Co(en)2Cl2]Cl配合物水解反应动力学常数测定"实验教学实施结果及探讨内容。引导学生以动力学实验数据和实验结果为依据,讨论和探究了介质、温度等对trans/cis-[Co(en)2Cl2]Cl配合物水解反应的影响,让学生直观认识顺-反异构体配合物的结构不同,所表现的水解反应动力学的差异,了解结构决定性质的涵义,培养学生归纳、总结、分析、判断的能力以及批判性思维能力。 展开更多
关键词 trans/cis-[Co(en)_(2)Cl_(2)]Cl 水解反应动力学 实验结果分析与探讨
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“trans/cis-[Co(en)_(2)Cl_(2)]Cl配合物的制备及其光谱鉴定”实验教学实施结果与探讨——培养学生批判性思维的典型案例之一
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作者 欧阳小清 张春艳 +8 位作者 潘蕊 阮婵姿 吕银云 翁玉华 董志强 彭淑女 李华敏 许振玲 任艳平 《大学化学》 CAS 2021年第3期79-86,共8页
主要介绍厦门大学专门为"化学拔尖计划"学生个性化培养"量身定制"的"trans/cis-[Co(en)_(2)Cl_(2)]Cl配合物的制备及其光谱鉴定"实验教学实施结果及探讨。以"trans/cis-[Co(en)_(2)Cl_(2)]Cl配合物... 主要介绍厦门大学专门为"化学拔尖计划"学生个性化培养"量身定制"的"trans/cis-[Co(en)_(2)Cl_(2)]Cl配合物的制备及其光谱鉴定"实验教学实施结果及探讨。以"trans/cis-[Co(en)_(2)Cl_(2)]Cl配合物的制备及其光谱鉴定"实验为载体,围绕着合成两大目标"质"和"量",也就是以如何才能得到又"好"又"多"的trans/cis-[Co(en)_(2)Cl_(2)]Cl配合物等问题为导向,以所展示的详细直观的制备流程和紫外-可见吸收光谱图为基础,以实验结果为依据,以设问、探讨的方式对合成过程、条件等进行仔细分析和深刻反思、判断,以展示实验教学过程中如何有效地培养学生的批判性思维。 展开更多
关键词 trans/cis-[Co(en)_(2)Cl_(2)]Cl 制备与鉴定 实验结果分析与探讨 翻转课堂 批判性思维
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dl-cis-和trans-4-乙酰氨基-2-正丁基-1-二甲氨基-5,6-亚甲二氧基茚满的合成
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作者 周智善 《上海医科大学学报》 CSCD 1992年第6期413-418,共6页
以细胞内钙拮抗剂Bu-MDI为先导化合物,设计合成了具有弱钙拮抗作用的4-乙酰氨基取代的茚满衍生物。该目标化合物以胡椒醛为起始原料,经十一步反应制得。合成中对1的格氏反应、2的脱水消除和5的制备等均作了改进,使收率有所提高。对5的... 以细胞内钙拮抗剂Bu-MDI为先导化合物,设计合成了具有弱钙拮抗作用的4-乙酰氨基取代的茚满衍生物。该目标化合物以胡椒醛为起始原料,经十一步反应制得。合成中对1的格氏反应、2的脱水消除和5的制备等均作了改进,使收率有所提高。对5的硝化产物6的硝基位置经NOE确证,并对目标化合物二对顺、反异构体的比例和生成机制作了讨论。 展开更多
关键词 Bu-MDI 钙拮抗剂 MDIs
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EFFECT OF CIS-9, TRANS-11-CONJUGATED LINOLEIC ACID ON CELL CYCLE OF MAMMARY ADENOCARCINOMA CELLS(MCF-7) 被引量:1
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作者 刘家仁 陈炳卿 +3 位作者 韩晓辉 杨艳梅 郑玉梅 刘瑞海 《Chinese Journal of Cancer Research》 SCIE CAS CSCD 2002年第2期93-99,共7页
Objective: To determine the effect of cis-9, trans-1 1-conjugated linoleic acid on the cell cycle of mammary cancer cells (MCF-7) and the possible mechanism of the inhibitory effect of c9,t11-CLA. Methods: Using cell ... Objective: To determine the effect of cis-9, trans-1 1-conjugated linoleic acid on the cell cycle of mammary cancer cells (MCF-7) and the possible mechanism of the inhibitory effect of c9,t11-CLA. Methods: Using cell culture and immunocytochemical techniques, we examined the cell growth, DNA synthesis, expression of PCNA, cyclin A, B1, D1, p16ink4a and p21cip/waf1 of MCF-7 cells at various c9,t11-CLA concentrations (25μM, 50μM, 100μM and 200μM), at 24h and 48h. 96% ethand was used as negative control. Results: The cell growth and DNA synthesis of MCF-7 cells were inhibited by c9,t11-CLA. After treatment with various doses of c9,t11-CLA mentioned above for 8 days, the inhibition frequency was 27.18%, 35.43%, 91.05%, and 92.86%, respectively. Inhibitory effect of c9,t11-CLA on DNA synthesis (except for 25μM, 24h) was demonstrated by significantly less incorporation of 3H-TdR than the negative control (P<0.05 and P<0.01). To further investigate the influence of the cell cycle progression, we found that c9,t11-CLA may arrest the cell cycle of MCF-7 cells. Immunocytochemical staining demonstrated that incubation with different concentration of c9,t11-CLA at various times significantly decreased the expression of PCNA, Cyclin A, B1, D1 in MCF-7 cells compared to the negative control (P<0.01), whereas the expression of p16ink4a and p21cip/waf1, cyclin-dependent kinases inhibitors (CDKI), were increased. Conclusions: The cell growth and proliferation of MCF-7 cells is inhibited by c9,t11-CLA via blocking cell cycle, accompanying reduced expression of cyclin A, B1, D1 and enhanced expression of CDKI (p16ink4a and p21cip/waf1). 展开更多
关键词 Mammary adenocarcinoma cells (MCF-7) cis-9 trans-11-conjugated linoleic acid(c9 t11-CLA) IMMUNOCYTOCHEMISTRY Cell cycle Inhibition
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Crystal Structure and Third order Nonlinear Optical Properties of cis-Configuration Biferrocene Trinuclear Complexes
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作者 WU Jie-ying TIAN Yu-peng +1 位作者 XIE Fu-xin NI Shi-sheng 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 1999年第3期218-225,共8页
The syntheses and characterization of novel biferrocene trinuclear complexes of Schiff base ligand, S methyl N (ferrocenyl 1 methyl methylidene)dithiocarbazate [hereafter abbreviated as HL (1)], are described. The X r... The syntheses and characterization of novel biferrocene trinuclear complexes of Schiff base ligand, S methyl N (ferrocenyl 1 methyl methylidene)dithiocarbazate [hereafter abbreviated as HL (1)], are described. The X ray diffraction studies have established the structures of PdL 2 (3) and CuL 2 (4). The geometry of Pd(Ⅱ) in (3) is close to a square plane and in the novel cis configuration the two ferrocene moieties are in cis configuration, while that of Cu(Ⅱ) in (4) is close to a tetrahedral configuration. The electrochemical measurements suggested that the square planar configuration of Ni(Ⅱ) and Pd(Ⅱ) moieties can effectively transmit the redox effects of the ferrocene moieties, while the tetrahedral configuration of the Cu(Ⅱ) complex can not transmit the redox effects. The degenerate four wave mixing (DFWM) measurements showed that the complexes exhibit obviously nonlinear optical (NLO) response. The magnitude of their third order NLO susceptibility can be explained by their structure and electrochemical properties. 展开更多
关键词 ELECTROCHEMISTRY cis configuration biferrocene Third order nonlinear optical property
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Cis-and Trans-Coordination Assembly of Nitrogen Heterocycle with Copper(Ⅱ) and Silver(Ⅰ)
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作者 TAN Di TAN Gui-ping +3 位作者 HUANG Xiao-chun TONG Shan-ling YANG Ke-er YAN Yan 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2008年第6期661-667,共7页
After the preparation of 1,4-bis(4,5-dihydro-lH-imidazol-2-yl)benzene(bdib), a nitrogen heterocycle with potential coordination manners of both cis- and trans-configuration forms, three complexes, including cis-[... After the preparation of 1,4-bis(4,5-dihydro-lH-imidazol-2-yl)benzene(bdib), a nitrogen heterocycle with potential coordination manners of both cis- and trans-configuration forms, three complexes, including cis-[Cuz(bdib )2(/L-OCH3)2]Cl2·2MeOH(1), trans-[Cu(bdib)(AcO)2]n(2), and cis-[Ag2(bdib)2](NO3)2.2H20(3), were successfully self-assembled. Complexes 1 and 2 crystallized in the monoclinic system with P21/n space group and complex 3 in the triclinic system with P1 space group. 展开更多
关键词 Nitrogen heterocycle cis- and trans-coordination COPPER SILVER
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A Convenient Synthesis of cis and trans-(±)-4-Amino-1-[2-(hydroxyl-methyl)-1,3-oxathiolan-5-yl]-2(1H)-pyrimidinone
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作者 Yi SHEN Ling XIANG Yong DENG Yu Guo ZHONG 《Chinese Chemical Letters》 SCIE CAS CSCD 2006年第4期431-433,共3页
A convenient synthesis of cis-(±) isomer 1 and trans-(±) isomer 2 of lamivudine starting from benzoyloxyacetaldehyde and 1,4-dithiane-2,5-diol is described. The key steps include chlorination of oxathiol... A convenient synthesis of cis-(±) isomer 1 and trans-(±) isomer 2 of lamivudine starting from benzoyloxyacetaldehyde and 1,4-dithiane-2,5-diol is described. The key steps include chlorination of oxathiolane lactol 5 by SOCl2/DMF, followed by coupling with silylated N^4- acetylcytosine and deprotection. The overall yield was 42.6 % and 20,1%, respectively. 展开更多
关键词 LAMIVUDINE geometrical isomer cis-(±) isomer trans-(±) isomer synthesis.
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A Novel Biferrocene Trinuclear Complex with Cis-Configuration
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作者 Jie Ying WU Yu Peng TIAN +1 位作者 Fu Xin XIE Shi Sheng NI(Department of Chemistry, Anhui University, Hefei 230039) 《Chinese Chemical Letters》 SCIE CAS CSCD 1999年第3期251-254,共4页
A novel biferocene trinuclear complex for Schiff base ligand S-methyl-N- (ferrocenyl-1-methyl -methylidene) dithiocarbazate thereafter abbreviated as HL) is described. X-ray diffraction studies established the structu... A novel biferocene trinuclear complex for Schiff base ligand S-methyl-N- (ferrocenyl-1-methyl -methylidene) dithiocarbazate thereafter abbreviated as HL) is described. X-ray diffraction studies established the structure of the palladium complex, PdL2. The geometry of Pd (II) in the complex is close to square planar and in novel cis-configuration with two ferrocene moieties on the same side. Degenerate four-wave mixing (DFWM) measurements show that the complex exhibit obvious nonlinear optical response. 展开更多
关键词 palladium complex cis-configuration biferrocene third-order nonlinear optical property
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Synthesis, Characterization and Photoinduced Cis-Trans Isomerisation Studies on Lignin Modified with 4-[(E)-2-(3-hydroxynaphthalen-2-yl)diazen-1-yl] Benzoic Acid
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作者 Ambily Chandran Sunny Kuriakose Tessymol Mathew 《Open Journal of Organic Polymer Materials》 2012年第4期69-74,共6页
In the present study, a photoresponsive chromophoric system such as 4-[(E)-2-(3-hydro xynaphthalen-2-yl)diazen-1-yl] benzoic acid was incorporated on to lignin core by functional transformation reactions and the photo... In the present study, a photoresponsive chromophoric system such as 4-[(E)-2-(3-hydro xynaphthalen-2-yl)diazen-1-yl] benzoic acid was incorporated on to lignin core by functional transformation reactions and the photoresponsive beha-vior of the green, environment friendly product was investigated. The end hydroxyl group of lignin was modified with the chromophoric systems by DCC coupling. The chromophoric systems as well as the chromophore-bound biopolymer core systems were purified by column chromatography. The products were characterized by UV-visible, fluorescence, FT-IR and NMR spectroscopic methods. The results of the studies show that incorporation of the chromophoric system on to the lignin core enhanced the light absorption, emission and light stabilization properties of the chromophoric system. The light fastening properties of chromophoric system and the modified product were compared. It shows that stability of the chromophoric system greatly enhanced on attaching to the polymeric system. The trans-cis photoisomerisation and the reverse cis-trans thermal conversions were also assisted by the lignin core. The remarkable stability on irradiation shows that this is a novel photoresponsive system with excellent light fastening properties which would find application in coating materials, dyes, paints, inks, therapeutic agents and many more. 展开更多
关键词 LIGNIN PHOTORESPONSIVE Environment Friendly Light Fastening cis-trans ISOMERISATION
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Solid state transformation of <i>cis</i>and <i>trans</i>methylcyclopentadienyl molybdenumdicarbonyltriphenylphosphineiodide on pelleting utilizing different diluents
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作者 Olalere G. Adeyemi Umaru Salami 《Open Journal of Inorganic Chemistry》 2012年第2期28-32,共5页
[(η5-C5H4Me)Mo(CO)2PPh3I] undergoes solid state transformation on the formation of a good pellet for FT IR measurement. There was a formation of the products mixture on pelleting using different diluents of group I m... [(η5-C5H4Me)Mo(CO)2PPh3I] undergoes solid state transformation on the formation of a good pellet for FT IR measurement. There was a formation of the products mixture on pelleting using different diluents of group I metal salts on either the cis or the trans isomer of the [(η5-C5H4Me)Mo(CO)2PPh3I] complex. The cis or the trans isomer gave the same IR spectra i.e. a mixture of cis and trans isomer of the complex. It does not matter the isomer started with in the course of solid state transformation reaction, an equilibrium ratio of 30/70 (trans/cis) will still be achieved. The solid state IR spectra show very strong peaks at νco 1957, 1947 and strong peaks at 1867, 1853 cm–1. The individual IR cis/trans isomer will therefore show at 1947 and 1853/1957 and 1867 cm–1. The solution IR spectra gave, cis = 1961, 1875 and trans = 1963, 1882 cm–1 in dry CHCl3. Hence, most of the solid state IR measurement of the organometallic complex of the type (η5-C5H4Me)Mo(CO)2(PPh3)I on pelleting will give isomer mixture. 展开更多
关键词 Solid State cis/trans-[(η5-C5H4Me)Mo(CO)2PPh3I] PELLETING DILUENTS FT IR
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ATRA和9-cis-RA对缺氧缺糖损伤PC12细胞凋亡的影响 被引量:4
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作者 江伟 温恩懿 +7 位作者 龚敏 瞿平 毕杨 张赟 魏小平 刘友学 陈洁 李廷玉 《第三军医大学学报》 CAS CSCD 北大核心 2010年第24期2595-2598,共4页
目的探讨不同构型视黄酸[全反式视黄酸(all-trans retinoic acid,ATRA);9顺式视黄酸(9-cis-retinoicacid,9-Cis-RA)]对缺氧缺糖损伤的PC12细胞凋亡的影响,且通过何种受体途径作用。方法实验分组为:未刺激组(0μmol/L RA);1、5、10μmol/... 目的探讨不同构型视黄酸[全反式视黄酸(all-trans retinoic acid,ATRA);9顺式视黄酸(9-cis-retinoicacid,9-Cis-RA)]对缺氧缺糖损伤的PC12细胞凋亡的影响,且通过何种受体途径作用。方法实验分组为:未刺激组(0μmol/L RA);1、5、10μmol/L,20μmol/L ATRA;1、5、10、20μmol/L9-CisRA。倒置显微镜观察缺氧缺糖损伤前后细胞形态变化,流式细胞术研究经不同浓度ATRA和9-Cis-RA刺激的缺氧缺糖损伤PC12细胞凋亡水平。ELISA监测ATRA和9-Cis-RA处理4 h后PC12细胞的LDH释放水平以了解其细胞膜损伤水平的差异。结果 ATRA组细胞凋亡率在1μmol/L浓度时与未刺激组无显著差异(P>0.05),从5μmol/L起随着浓度的增高凋亡率显著增高(P<0.05),在10、20μmol/L浓度组均显著高于相同浓度的9-Cis-RA组(P<0.05)和未刺激组(P<0.05);而9-Cis-RA在20μmol/L组凋亡率低于未刺激组,但无显著性差异(P>0.05)。乳酸脱氢酶(LDH)释放水平在ATRA刺激组从5μmol/L起随浓度的增高而显著性增高(P<0.01),在5、10、20μmol/L浓度均显著高于未刺激组和9-Cis-RA组(P<0.05),而在各浓度9-Cis-RA组与未刺激组均无显著性差异(P>0.05)。在RA信号系统中ATRA特异激活retinoic acid receptors(RARs),而9-Cis-RA同时激活RARs和retinoid X receptors(RXRs)。结论在缺氧缺糖损伤的PC12细胞ATRA可通过激活RARs受体途径发挥促凋亡效应,但这种效应可以被激活RXRs受体途径而抑制。 展开更多
关键词 全反式视黄酸 9顺式视黄酸 视黄酸核受体 视黄醇X受体 PC12细胞 缺氧缺糖 凋亡
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Trans-α-乙炔基-2-甲基-2-戊烯-2,2-二甲基-3-(2,2-二氯乙烯基)环丙烷羧酸酯的合成 被引量:1
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作者 李科 《中国药物化学杂志》 CAS CSCD 1995年第3期199-201,207,共4页
以丙醛和混合二氯菊酸甲酯为原料,经缩合、格氏加成,顺反分离,酯化等反应,全合成了新型家庭卫生杀虫药Trans-α-乙炔基-2-甲基-2-戊烯-2,2-二甲基-3-(2,2-二氯乙烯基)环丙烷羧酸酯。
关键词 拟除虫菊酯 合成 环丙烷羧酸酯 合成
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3-Phenyl/Pyridinyl Derivatives of <i>Trans</i>-2-(aryl/heteryl)vinyl-3<i>H</i>-quinazolin-4-ones: Synthesis and Fluorescent Properties
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作者 Emiliya V. Nosova Tatyana V. Stupina +3 位作者 Galina N. Lipunova Marina S. Valova Pavel A. Slepukhin Valery N. Charushin 《International Journal of Organic Chemistry》 2012年第1期56-63,共8页
Novel 3-phenyl/pyridinyl-trans-2-(aryl/heteryl)vinyl-3H-quinazolin-4-ones 3a,b, 4a, 5a, 7a and their 6,7-difluoro de- rivatives 3c,d, 4b, 5b, 7b have been obtained by condensation of the correspondent 2-methylquinazol... Novel 3-phenyl/pyridinyl-trans-2-(aryl/heteryl)vinyl-3H-quinazolin-4-ones 3a,b, 4a, 5a, 7a and their 6,7-difluoro de- rivatives 3c,d, 4b, 5b, 7b have been obtained by condensation of the correspondent 2-methylquinazolin-4-ones 1, 6 with aromatic (heterocyclic) aldehydes in the presence of ZnCl2 (AcONa) or by the reaction of 2-methyl-3,1-benzoxazin-4- ones 2 with the Shiff bases. Effects of aryl(heteryl) substituents on photophysical properties of (aryl/heteryl) quinazolinylethenes have been studied. 展开更多
关键词 Styryl Benzazines Fluorinated Quinazolin-4-Ones UV and FL Spectra X-Ray trans-cis-Isomerisation 2-Methylquinazolinones 2-Methyl-3 1-benzoxazinones
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新能源大基地风光储容量协调优化配置 被引量:4
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作者 李明轩 范越 +3 位作者 汪莹 王炜 牛拴保 魏韡 《电力自动化设备》 EI CSCD 北大核心 2024年第3期1-8,共8页
大型新能源基地需要协调配置风光火储容量以满足外送要求,其中火电容量及外送通道的容量通常预先确定,从而风电、光伏、储能的容量配置成为影响新能源外送效果的重要因素。为此,针对大型新能源基地,研究了风光储容量优化配置问题,提出... 大型新能源基地需要协调配置风光火储容量以满足外送要求,其中火电容量及外送通道的容量通常预先确定,从而风电、光伏、储能的容量配置成为影响新能源外送效果的重要因素。为此,针对大型新能源基地,研究了风光储容量优化配置问题,提出了基于新能源外送可靠性的容量配置方法。基于需求侧的负荷曲线,提出了一种聚类方法来优化直流通道的计划传输功率;基于直流计划功率,提出了衡量新能源外送可靠性的送电置信概率指标;基于送电置信概率等约束,构建了风光储容量优化配置的基本规划模型。为了进一步保证在不同的场景下新能源能可靠外送,在基本规划模型的基础上加入场景分布不确定性,提出了风光储容量配置的分布鲁棒规划模型。考虑到分布鲁棒约束包含整数变量,提出了一种迭代算法用于该分布鲁棒规划模型的求解。实际算例验证了所提方法的有效性。 展开更多
关键词 新能源 风光储协调规划 直流送电计划 置信概率 分布鲁棒优化 容量配置
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木薯MeHsfB3b转录因子与MeFKBP20蛋白互作关系验证
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作者 王超群 李琳琳 +3 位作者 陈银华 张肖飞 姚远 耿梦婷 《热带作物学报》 CSCD 北大核心 2024年第3期450-458,共9页
热激转录因子MeHsfB3b是调控木薯抗细菌性枯萎病的重要节点,前期通过酵母双杂交技术获得MeHsfB3b的候选互作蛋白MeFKBP20,该蛋白属于FKBP型肽脯氨酰顺反异构酶基因家族。本研究克隆获得MeFKBP20基因全长为561 bp,编码186个氨基酸,蛋白... 热激转录因子MeHsfB3b是调控木薯抗细菌性枯萎病的重要节点,前期通过酵母双杂交技术获得MeHsfB3b的候选互作蛋白MeFKBP20,该蛋白属于FKBP型肽脯氨酰顺反异构酶基因家族。本研究克隆获得MeFKBP20基因全长为561 bp,编码186个氨基酸,蛋白质分子质量为19.99 kDa,具有FKPB_C结构域。表达模式分析发现:MeFKBP20基因在木薯成熟叶片及根部高表达,在幼叶和叶柄的表达量较低;并能够迅速响应病原菌XpmCHN11诱导,持续保持较高的表达丰度,推测其参与了木薯响应病原菌侵染的过程。利用酵母双杂交点对点、双分子荧光互补实验证明MeHsfB3b蛋白通过在201~241 aa区域与MeFKBP20蛋白作用。本研究结果有助于进一步解析MeHsfB3b基因调控木薯对细菌性枯萎病的抗病机理。 展开更多
关键词 热激转录因子 FKBP型肽脯氨酰顺反异构酶 酵母双杂交 双分子荧光互补
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黄海葵附生真菌Penicillium sp.化学成分的研究(Ⅰ) 被引量:14
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作者 蒋亭 田黎 +2 位作者 劳彦斌 李军 林文翰 《中国海洋药物》 CAS CSCD 2001年第3期40-42,共3页
从黄海葵 [Anthopleura xanthogrammica(Berkly) ]附生真菌 Penicillium sp.的发酵液中首次分离到4个化合物 ,分别鉴定为 :对羟基苯乙醇 ( ) ,(Z) N- [2 - (4-羟基苯基 )乙烯基 ]甲酰胺 ( ) ;(E) N- [2 - (4-羟基苯基 )乙烯基 ]甲酰胺 (... 从黄海葵 [Anthopleura xanthogrammica(Berkly) ]附生真菌 Penicillium sp.的发酵液中首次分离到4个化合物 ,分别鉴定为 :对羟基苯乙醇 ( ) ,(Z) N- [2 - (4-羟基苯基 )乙烯基 ]甲酰胺 ( ) ;(E) N- [2 - (4-羟基苯基 )乙烯基 ]甲酰胺 ( ) ,邻苯二甲酸二异丁基酯 ( ) ,其中化合物 ( )为首次从天然界分离得到。它们的化学结构经理化数据和波谱分析 。 展开更多
关键词 PENIciLLIUM SP (E)N-[2-(4-羟在苯基)乙烯基]甲酰胺 化学成分 黄海葵 附生真菌
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