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Piezo-Photocatalytic Technology Based on Bismuth Ferrite(Bi_(2)Fe_(4)O_(9))for Degradation of Reactive Dye KN-R
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作者 ZHU Feishi HU Chunyan LIU Baojiang 《Journal of Donghua University(English Edition)》 2025年第1期1-11,共11页
Dyeing wastewater poses a serious threat to environmental protection and industrial development.The piezoelectric effect can be used to optimize the band structure of semiconductors and improve the photon efficiency o... Dyeing wastewater poses a serious threat to environmental protection and industrial development.The piezoelectric effect can be used to optimize the band structure of semiconductors and improve the photon efficiency of photocatalysts.Bi_(2)Fe_(4)O_(9),a narrow gap semiconductor with piezoelectric effect,was prepared by a hydrothermal synthesis method for the degradation of reactive dye KN-R.The results show that the degradation efficiency of KN-R can be significantly improved by piezo-photocatalysis,and the degradation rate constant of piezo-photocatalysis k_(pi-ph)is about 3.4 times as large as the degradation rate constant of piezoelectric catalysis k_(pi)and about 2.6 times as large as the degradation rate constant of photocatalysis k_(ph).At a pH value of 3 and a lower KN-R mass concentration(60 mg/L),a higher degradation efficiency(98.5%)is achieved.CO_(3)^(2-)and cationic surfactant(CTAB)inhibit the degradation of KN-R.It is proved that the contributions of different active species to the degradation of KN-R follow the order:·OH,·O_(2)^(-),h^(+),and^(1)O_(2).The possible mechanism of piezo-photocatalytic degradation of KN-R was discussed.The photoexcitation generates a large amount of free charges,and the piezoelectric effect modulates the energy band structure of Bi_(2)Fe_(4)O_(9)and promotes the separation of photogenerated electron-hole pairs.The synergistic effect of the two factors significantly improves the degradation efficiency of KN-R. 展开更多
关键词 Bi_(2)Fe_(4)O_(9) piezo-photocatalysis DEGrADATION wastewater treatment reactive dye KN-r
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两相体系中固定化黏红酵母CCZU-G5催化合成(R)-2-羟基-4-苯基丁酸乙酯 被引量:3
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作者 汪云 王利群 +3 位作者 何玉财 朱劼 卿青 王明慧 《化工进展》 EI CAS CSCD 北大核心 2013年第3期661-665,共5页
通过筛选得到一株高立体选择性还原2-氧代-4-苯基丁酸乙酯(OPBE)合成(R)-2-羟基-4-苯基丁酸乙酯[(R)-HPBE]的菌株并鉴定为黏红酵母。研究了在异辛烷/水两相体系中固定化黏红酵母CCZU-G5不对称还原OPBE合成(R)-HPBE的反应条件。结果表明... 通过筛选得到一株高立体选择性还原2-氧代-4-苯基丁酸乙酯(OPBE)合成(R)-2-羟基-4-苯基丁酸乙酯[(R)-HPBE]的菌株并鉴定为黏红酵母。研究了在异辛烷/水两相体系中固定化黏红酵母CCZU-G5不对称还原OPBE合成(R)-HPBE的反应条件。结果表明最适的反应条件为:在异辛烷比例为10%条件下,底物浓度为100mmol/L,催化剂用量为0.45 g/mL,辅底物为40 g/L的葡萄糖。在建立的反应体系中反应16 h,(R)-HPBE产率最高,达83.5%,e.e.值99%以上。固定化酵母经7次重复使用后,产率和e.e.值分别维持在70%和99%以上。 展开更多
关键词 两相体系 固定化 rHODOTOruLA mucilaginosaCCZu-G5 (r)-2-羟基-4-苯基丁酸乙酯 不对称还原
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聚苯胺包覆碳点功能化CoMn_(2)O_(4)去除废水中U(Ⅵ)的性能与机制
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作者 周鑫艳 王月 《复合材料学报》 北大核心 2025年第7期3878-3890,共13页
核工业发展产生的含铀废水对人类健康和生态环境产生严重威胁。对含铀废水的有效化处理是核能绿色发展的重要保证。采用化学聚合法合成了一种新型聚苯胺包覆碳点功能化锰钴金属氧化物(CMC20%/PANI)。吸附剂表面丰富的氧、氮基团为U(Ⅵ)... 核工业发展产生的含铀废水对人类健康和生态环境产生严重威胁。对含铀废水的有效化处理是核能绿色发展的重要保证。采用化学聚合法合成了一种新型聚苯胺包覆碳点功能化锰钴金属氧化物(CMC20%/PANI)。吸附剂表面丰富的氧、氮基团为U(Ⅵ)的高效捕获提供活性位点。采用静态吸附法研究了材料去除溶液中U(Ⅵ)的性能。因此,在pH=5、120 min,CMC20%/PANI对U(Ⅵ)的吸附容量达到285 mg/g。吸附过程符合准二级动力学和Sips模型,表明吸附剂对铀涉及单层和多层的化学吸附,并且Sips拟合的理论吸附容量为659.8 mg/g。吸附机制研究表明:静电吸引、孔扩散以及含氧、氮基团的络合配位作用成为CMC20%/PANI对U(Ⅵ)的主要去除机制。 展开更多
关键词 CoMn_(2)O_(4) PANI CDS 吸附法 u(Ⅵ) 废水
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Synthesis,biological activities and 3D-QSAR studies of(R)-2-phenyl-4,5-dihydrothiazole-4-carboxamide derivatives containing a sulfur ether moiety 被引量:5
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作者 Jingbo Liu Fengyun Li +5 位作者 Yuanhong Wang Haoxuan Zhang Jingyue Dong Pengwei Sun Yuxin Li Zhengming Li 《Chinese Chemical Letters》 SCIE CAS CSCD 2019年第3期668-671,共4页
A series of(R)-2-phenyl-4,5-dihydrothiazole-4-carboxamide derivatives containing a sulfur ether moiety were synthesized and characterized on the basis of NMR and elemental analysis(EA). The crystal structure of(R)-N-(... A series of(R)-2-phenyl-4,5-dihydrothiazole-4-carboxamide derivatives containing a sulfur ether moiety were synthesized and characterized on the basis of NMR and elemental analysis(EA). The crystal structure of(R)-N-(2-methyl-1-(methylthio)propan-2-yl)-2-(4-nitrophenyl)-4,5-dihydrothiazole-4-carboxamide(13 d) was determined to show R configuration. The bioasssy results indicated that most title compounds displayed good and broad spectrum antifungal activities against several phytopathogenic fungi. The structure activity relationships were discussed. Based on the antifungal activity of title compounds against Phytophthora capsici, a CoMSIA calculation was performed to establish a 3 D-QSAR model, which revealed that electrostatic and hydrophobic fields were the two most significant factors for antifungal activity. According to the established 3D-QSAR model, structure optimization was carried out to find(R)-N-((R)-1-(methylthio)propan-2-yl)-2-(p-tolyl)-4,5-dihydrothiazole-4-carboxamide(15 h)with excellent activity against Phytophthora capsici, thus emerging as a new lead compound for novel antiphytopathogenic fungus agent development. 展开更多
关键词 (r)-2-Phenyl-4 5-dihydrothiazole-4- CArBOXAMIDE SuLFur ETHEr Antifungal activity SArs COMSIA model
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P2X7/P2X4 Receptors Mediate Proliferation and Migration of Retinal Microglia in Experimental Glaucoma in Mice 被引量:7
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作者 Meng-Xi Xu Guo-Li Zhao +6 位作者 Xin Hu Han Zhou Shu-Ying Li Fang Li Yanying Miao Bo Lei Zhongfeng Wang 《Neuroscience Bulletin》 SCIE CAS CSCD 2022年第8期901-915,共15页
Microglia are involved in the inflammatory response and retinal ganglion cell damage in glaucoma.Here,we investigated how microglia proliferate and migrate in a mouse model of chronic ocular hypertension(COH).In COH r... Microglia are involved in the inflammatory response and retinal ganglion cell damage in glaucoma.Here,we investigated how microglia proliferate and migrate in a mouse model of chronic ocular hypertension(COH).In COH retinas,the microglial proliferation that occurred was inhibited by the P2X7 receptor(P2X7R)blocker BBG or P2X7R knockout,but not by the P2X4R blocker 5-BDBD.Treatment of primary cultured microglia with BzATP,a P2X7R agonist,mimicked the effects of cell proliferation and migration in COH retinas through the intracellular MEK/ERK signaling pathway.Transwell migration assays showed that the P2X4R agonist CTP induced microglial migration,which was completely blocked by 5-BDBD.In vivo and in vitro experiments demonstrated that ATP,released from activated Müller cells through connexin43 hemichannels,acted on P2X7R to induce microglial proliferation,and acted on P2X4R/P2X7R(mainly P2X4R)to induce microglial migration.Our results suggest that inhibiting the interaction of Müller cells and microglia may attenuate microglial proliferation and migration in glaucoma. 展开更多
关键词 Glaucoma Chronic ocular hypertension retinal microglia PrOLIFErATION MIGrATION P2X7r/P2X4r Müller cells
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P2X4 receptor participates in autophagy regulation in Parkinson’s disease 被引量:3
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作者 Xue Zhang Jing Wang +4 位作者 Jin-Zhao Gao Xiao-Na Zhang Kai-Xin Dou Wan-Da Shi An-Mu Xie 《Neural Regeneration Research》 SCIE CAS CSCD 2021年第12期2505-2511,共7页
Dysfunctional autophagy often occurs during the development of neurodegenerative diseases,such as Parkinson’s disease,Huntington’s disease,and Alzheimer’s disease.The purinergic P2X4 receptor is an ATP-gated ion ch... Dysfunctional autophagy often occurs during the development of neurodegenerative diseases,such as Parkinson’s disease,Huntington’s disease,and Alzheimer’s disease.The purinergic P2X4 receptor is an ATP-gated ion channel that is widely expressed in the microglia,astrocytes,and neurons of the central and peripheral nervous systems.P2X4R is involved in the regulation of cellular excitability,synaptic transmission,and neuroinflammation.However,the role played by P2X4R in Parkinson’s disease remains poorly understood.Rat models of Parkinson’s disease were established by injecting 6-hydroxydopamine into the substantia nigra pars compacta.P2X4R-targeted small interfering RNA(siRNA)was injected into the same area 1 week before injury induction to inhibit the expression of the P2X4 receptor.The results showed that the inhibition of P2X4 receptor expression in Parkinson’s disease model rats reduced the rotation behavior induced by apomorphine treatment,increased the latency on the rotarod test,and upregulated the expression of tyrosine hydroxylase,brain-derived neurotrophic factor,LC3-II/LC3-I,Beclin-1,and phosphorylated tropomyosin receptor kinase B(TrkB)in brain tissue,while simultaneously reducing p62 levels.These findings suggest that P2X4 receptor activation might inhibit neuronal autophagy through the regulation of the brain-derived neurotrophic factor/TrkB signaling pathway,leading to dopaminergic neuron damage in the substantia nigra and the further inhibition of P2X4 receptor-mediated autophagy.These results indicate that P2X4 receptor might serve as a potential novel target for the treatment of Parkinson’s disease.This study was approved by the Animal Ethics Committee of Affiliated Hospital of Qingdao University(approval No.QYFYWZLL26119)on April 12,2016. 展开更多
关键词 6-HYDrOXYDOPAMINE APOMOrPHINE brain-derived neurotrophic factor dopaminergic neurons neuron degeneration P2X4r Parkinson’s disease TrKB AuTOPHAGY
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Enantioselective Hydrogenation of Ethyl 2-Oxo-4-phenylbutyrate on Cinchona-Platinum Catalysts 被引量:2
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作者 夏涛 任其龙 吴平东 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2005年第6期764-770,共7页
Enantioselective hydrogenation of ethyl 2-oxo-4-phenylbutyrate to ethyl (R)-2-hydroxy-4-phenyl- bu- tyrate on Pt/γ-Al2O3 modified by 10,11-dihydrocinchonidine was studied by investigating the influences of the amou... Enantioselective hydrogenation of ethyl 2-oxo-4-phenylbutyrate to ethyl (R)-2-hydroxy-4-phenyl- bu- tyrate on Pt/γ-Al2O3 modified by 10,11-dihydrocinchonidine was studied by investigating the influences of the amount of modifier, initial concentration of reactant, pressure and temperature on conversion and enantiometric excess in a stirred autoclave and the effects of the liquid velocity, gas velocity, modifier concentration and various catalytic beds in a trickle-bed reactor. The maximum optical yields were about 50% and 60% in the two types of reactors, respectively. It was assumed that the total hydrogenation rate included the reaction rates over the unmodified and modified active sites on platinum surface and a kinetic model, which fitted the experimental data well in autoclave, was obtained. A simplified plug-flow model was proposed to describe the bed average efficiency of trickle-bed reactor. 展开更多
关键词 enantioselective hydrogenation ethyl r)-2-hydroxy-4-phenylbutyrate trickle-bed reactor KINETICS
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Domesticated HERV-W env contributes to the activation of the small conductance Ca^(2+)-activated K^(+)type 2 channels via decreased 5-HT4 receptor in recent-onset schizophrenia 被引量:1
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作者 Xiulin Wua Qiujin Yan +8 位作者 Lianzhong Liu Xing Xue Wei Yao Xuhang Li Wenshi Li Shuang Ding Yaru Xia Dongyan Zhang Fan Zhu 《Virologica Sinica》 SCIE CAS CSCD 2023年第1期9-22,共14页
The human endogenous retroviruses type W family envelope(HERV-W env)gene is located on chromosome 7q21-22.Our previous studies show that HERV-W env is elevated in schizophrenia and HERV-W env can increase cal-cium inf... The human endogenous retroviruses type W family envelope(HERV-W env)gene is located on chromosome 7q21-22.Our previous studies show that HERV-W env is elevated in schizophrenia and HERV-W env can increase cal-cium influx.Additionally,the 5-HTergie system and particularly 5-hydroxytryptamine(5-HT)receptors play a prominent role in the pathogenesis and treatment of schizophrenia.5-hydroxytryptamine receptor 4(5-HT4R)agonist can block calcium channels.However,the underlying relationship between HERV-W env and 5-HT4R in the etiology of schizophrenia has not been revealed.Here,we used enzyme-linked immunosorbent assay to detect the concentration of HERV-W env and 5-HT4R in the plasma of patients with schizophrenia and we found that there were decreased levels of 5-HT4R and a negative correlation between 5-HT4R and HERV-W env in schizophrenia.Overexpression of HERV-W env decreased the transcription and protein levels of 5-HT4R but increased small conductance Ca^(2+)-activated K^(+)type 2 channels(SK2)expression levels.Further studies revealed that HERV-w env could interact with 5-HT4R.Additionally,luciferase assay showed that an essential region(-364 to-176 from the transcription start site)in the SK2 promoter was required for HERV-W env-induced SK2 expression.Importantly,5-HT4R participated in the regulation of SK2 expression and promoter activity.Electrophysiological recordings suggested that HERV-Wenv could increase SK2 channel currents and the increase of SK2 currents was inhibited by 5-HT4R.In condusion,HERV-W env could activate SK2 channels via decreased 5-HT4R,which might exhibit a novel mechanism for HERV-Wenv to influence neuronal activity in schizophrenia. 展开更多
关键词 Human endogenous retroviruses type W(HErV-W) ENV Small conductance Ca^(2%PLuS%)-activated K^(%PLuS%)type 2 channels(SK2) 5-Hydroxytryptamine receptor 4(5-HT4r) SCHIZOPHrENIA
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乙肝病程发展中CD4/CD8、TNF-α及sIL-2R水平变化及意义 被引量:28
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作者 殷缨 张盈华 张利朝 《免疫学杂志》 CAS CSCD 北大核心 2002年第1期74-74,共1页
关键词 乙型肝炎 病程 CD4/CD8 TNFΑ SIL-2r
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Crystal Structure and Biological Activities of (R)-N′-[2-(4-Methoxy-6-chloro)-pyrimidinyl]-N-[3-methyl-2-(4-chlorophenyl)butyryl]-urea
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作者 LI Jing-Zhi XUE Si-Jia LIU Guo-Hua 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2006年第8期903-908,共6页
The title compound (R)-N′-[2-(4-methoxy-6-chloro)-pyrimidyl]-N-[3-methyl-2-(4- chlorophenyl)butyryl]-urea has been synthesized, and its crystal structure and biological behaviors were studied. Crystallographic ... The title compound (R)-N′-[2-(4-methoxy-6-chloro)-pyrimidyl]-N-[3-methyl-2-(4- chlorophenyl)butyryl]-urea has been synthesized, and its crystal structure and biological behaviors were studied. Crystallographic data: C17H18C12N4O3, Mr = 397.25, monoclinic, space group P21/c, a = 12.331(2), b = 14.025(3), c = 23.085(5) A, β = 99.607(4)°, Z = 8, V = 3936.2(13) A3, Dc = 1.341 g/cm^3, F(000) = 1648, R = 0.0718, wR = 0.1585 and/t(MoKα) = 0.353 mm^-1. The preliminary biological tests showed that the title compound has definite insecticidal and fungicidal activities. 展开更多
关键词 crystal structure biological activity r)-3-methyl-2-(4-chlorophenyl)butyric acid 2-amino-6-chloro-4-methoxy-pyrimidine
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Synthesis and Crystal Structure of (R)-4-Hydroxymethyl-2-thioxo Thiazolidine and Its Asymmetric Catalysis
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作者 LI Jing SHANG Yan-mei +3 位作者 XIAO Chuan SONG Zhi-guang LI Ye-zhi HUANG Hua-min 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2009年第1期43-46,共4页
(R)-4-Hydroxymethyl-2-thioxo thiazolidine as a new chiral catalyst in the asymmetric addition of diethylzinc to benzaldehyde was synthesized from (R)-4-hydroxymethyl-2-thioxo thiazolidine carboxylic acid and its c... (R)-4-Hydroxymethyl-2-thioxo thiazolidine as a new chiral catalyst in the asymmetric addition of diethylzinc to benzaldehyde was synthesized from (R)-4-hydroxymethyl-2-thioxo thiazolidine carboxylic acid and its crystal structure was determined by X-ray diffraction method. The compound was crystallized in the orthorhombic system, space group P212121 with unit cell dimensions a=0.67253(12) nm; b=0.89164(17) nm; c=1.06146(19) nm, volume 0.6365(2) nm^3; Z=4, calculated denisity 1.557 Mg/m^3; absorption coefficient 0.733 mm^-1; F(000)=312. The X-ray crystal structure analysis reveals that the compound has a thione group. 展开更多
关键词 Crystal structure ASYMMETrIC r)-4-Hydroxymethyl-2-thioxothiazolidine
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(R)-2-羟基-4-苯基丁酸乙酯的合成 被引量:9
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作者 林文清 张晓梅 宓爱巧 《合成化学》 CAS CSCD 2002年第5期385-390,456,共7页
综述了血管紧张素转化酶抑制剂类治疗高血压和充血性心力衰竭药物的关键中间体 ( R) -2 -羟基 -4 -苯基丁酸乙酯的合成方法。参考文献 2
关键词 (r)-2-羟基-4-苯基丁酸乙酯 药物中间体 合成 综述 血管紧张素转化酶抑制剂 充血性心力衰竭药物
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三维封装DDR2存储器VD2D4G72XB191 XX3U6测试 被引量:2
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作者 汤凡 占连样 +2 位作者 陈像 王鑫 王烈洋 《电子产品世界》 2022年第5期78-82,共5页
DDR2 SDRAM具有速度快、价格便宜、容量大的特点,应用非常广泛。通过采用三维封装技术将5片数据位宽为16 bits的DDR2 SDRAM芯片封装成一个存储模块VD2D4G72XB191XX3U6,在不额外占用PCB面积的情况下,提高了存储容量,并将位宽扩展到72 bit... DDR2 SDRAM具有速度快、价格便宜、容量大的特点,应用非常广泛。通过采用三维封装技术将5片数据位宽为16 bits的DDR2 SDRAM芯片封装成一个存储模块VD2D4G72XB191XX3U6,在不额外占用PCB面积的情况下,提高了存储容量,并将位宽扩展到72 bits。与其它存储器相比DDR2 SDRAM操作较为复杂,封装成一个位宽72bit的模块后,测试难度进一步增加,针对这一问题,本文提出了基于Magnum 2测试系统的DDR2 SDRAM存储模块VD2D4G72XB191XX3U6的测试方法,对直流参数、交流参数以及功能进行了测试,论述了测试的关键技术。 展开更多
关键词 DDr2 SDrAM Magnum 2测试系统 VD2D4G72XB191XX3u6
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淡色库蚊细胞色素P450 CYP4E2r6基因的克隆、表达及鉴定 被引量:6
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作者 李秀兰 滕达 +2 位作者 孙艳 马磊 朱昌亮 《中国人兽共患病杂志》 CAS CSCD 北大核心 2005年第7期552-557,共6页
目的克隆并表达鉴定淡色库蚊细胞色素P450(CYP4E2r6)基因。方法根据昆虫细胞色素P450氨基酸保守序列设计一对简并引物,采用RT-PCR,从淡色库蚊四龄幼虫mRNA中扩增出目的基因片段。产物经T-A克隆、测序、比对,在抗性品系高表达的CYP4E2r6... 目的克隆并表达鉴定淡色库蚊细胞色素P450(CYP4E2r6)基因。方法根据昆虫细胞色素P450氨基酸保守序列设计一对简并引物,采用RT-PCR,从淡色库蚊四龄幼虫mRNA中扩增出目的基因片段。产物经T-A克隆、测序、比对,在抗性品系高表达的CYP4E2r6亚克隆入原核表达载体pGEX-6P1,在大肠杆菌BL21中进行原核表达,将细菌总蛋白进行SDS-PAGE及Westernblot鉴定。结果14个阳性克隆中9个为CYP4新序列,由GenBank登录上网(GenBank/NCBICB074944-51、CB270837,2003年);经鉴定属CYP4家族CYP4H、CYP4E、CYP4J亚家族;CYP4E2r6基因已成功表达。结论获得的CYP4E2r6融合表达蛋白为进一步研究CYP4基因与抗药性之间的关系奠定基础。 展开更多
关键词 淡色库蚊 细胞色素P450 CYP4E2r6 原核表达
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不对称催化合成(R)-2-羟基-4-苯基丁酸乙酯 被引量:4
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作者 夏涛 任其龙 吴平东 《化学反应工程与工艺》 EI CAS CSCD 北大核心 2005年第3期251-256,共6页
用 Pt-Cinchona 生物碱体系催化加氢合成(R)-2-羟基-4-苯基丁酸乙酯。进行了催化剂的制备和比较研究,并考察了修饰剂用量、2-氧代-4-苯基丁酸乙酯的初始浓度、反应氢压和温度对转化率和(R)-2-羟基-4-苯基丁酸乙酯得率的影响,得到了适宜... 用 Pt-Cinchona 生物碱体系催化加氢合成(R)-2-羟基-4-苯基丁酸乙酯。进行了催化剂的制备和比较研究,并考察了修饰剂用量、2-氧代-4-苯基丁酸乙酯的初始浓度、反应氢压和温度对转化率和(R)-2-羟基-4-苯基丁酸乙酯得率的影响,得到了适宜的反应条件,在此条件下产物中(R)-2-羟基-4-苯基丁酸乙酯得率可达70%以上。实验结果表明,本研究中不对称加氢速率与光学收率呈良好线性关系,对研究不对称合成反应的规律有一定的意义。 展开更多
关键词 不对称合成 (r)-2-羟基-4-苯基丁酸乙酯 催化加氢 光学收率 催化剂 血管紧张素转化酶抑制剂
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(R)-四氢噻唑-2-硫酮-4-羧酸的合成及其晶体结构 被引量:12
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作者 李叶芝 郭纯孝 +1 位作者 胡学山 黄化民 《高等学校化学学报》 SCIE EI CAS CSCD 北大核心 1997年第6期898-901,共4页
由L-半胱氨酸盐酸盐与二硫化碳在NaOH及CuSO4·H2O存在下反应得到(R)-四氢噻唑-2-疏酮-4-羧酸,[α]20D—87.5°,产率66%.用X射线衍射法测得其晶体结构,属正交晶系,Pz1z1z1空间群,晶体学参数:α=0.5029(2)nm,b... 由L-半胱氨酸盐酸盐与二硫化碳在NaOH及CuSO4·H2O存在下反应得到(R)-四氢噻唑-2-疏酮-4-羧酸,[α]20D—87.5°,产率66%.用X射线衍射法测得其晶体结构,属正交晶系,Pz1z1z1空间群,晶体学参数:α=0.5029(2)nm,b=0.7749(5)nm,c=1.6300(5)nm,V=0.6350(5)nm3,Z=4.用分子轨道(PM3)方法研究了该化合物的电子结构,得到其前线轨道性质.电荷和键序分布,并讨论了活性部位. 展开更多
关键词 TTCA 晶体结构 四氢噻唑 硫酮 羧酸 分子轨道
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(R)-3-(3-氟-4-吗啉苯基)-2-氧-5-噁唑烷基甲醇的合成 被引量:3
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作者 庞华 张君仁 +2 位作者 王子兰 冉祥凯 杜金 《精细化工》 EI CAS CSCD 北大核心 2004年第1期70-71,75,共3页
以3,4 二氟硝基苯为原料,与吗啉在二异丙基乙胺中反应4h得到3 氟 4 吗啉硝基苯(Ⅰ),在w(Pd)=10%催化下,Ⅰ与甲酸铵在V(THF)∶V(甲醇)=1∶4中反应6h,得3 氟 4 吗啉苯胺(Ⅱ),Ⅱ与光气在通入干燥HCl气体下反应得3 氟 4 吗啉异氰酸苯酯(Ⅲ)... 以3,4 二氟硝基苯为原料,与吗啉在二异丙基乙胺中反应4h得到3 氟 4 吗啉硝基苯(Ⅰ),在w(Pd)=10%催化下,Ⅰ与甲酸铵在V(THF)∶V(甲醇)=1∶4中反应6h,得3 氟 4 吗啉苯胺(Ⅱ),Ⅱ与光气在通入干燥HCl气体下反应得3 氟 4 吗啉异氰酸苯酯(Ⅲ),最后在无水LiBr和n Bu3PO催化下,Ⅲ与(R) 丁酸缩水甘油酯在二甲苯中反应2h,所得产物在甲醇钠催化下,与甲醇反应3h,合成了(R) 3 (3 氟 4 吗啉苯基) 2 氧 5 口恶唑烷基甲醇(Ⅳ),总收率35 8%。 展开更多
关键词 (r)-3-(3-氟-4-吗啉苯基)-2-氧-5-噁唑烷基甲醇 利奈唑酮 噁唑烷
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茂金属配合物 [(eat^5-C_5H_4R)Mo(CO)_3]_2(R:SiMe_3,Si_2Me_5)的电子结构研究 被引量:12
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作者 邝代治 冯泳兰 +3 位作者 许金生 王剑秋 张复兴 周秀中 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 北大核心 2003年第1期59-63,共5页
运用G98W ,采用Lanl2dz基组 ,对茂金属配合物 [(eat5 C5H4R)Mo(CO) 3 ]2 (R :SiMe3 ,Si2 Me5)进行从头算研究 ,探讨配合物结构单元的稳定性、分子轨道能量、原子净电荷布居规律 ,以及一些前沿分子轨道的组成特征等 ,结果表明 ,标题配合... 运用G98W ,采用Lanl2dz基组 ,对茂金属配合物 [(eat5 C5H4R)Mo(CO) 3 ]2 (R :SiMe3 ,Si2 Me5)进行从头算研究 ,探讨配合物结构单元的稳定性、分子轨道能量、原子净电荷布居规律 ,以及一些前沿分子轨道的组成特征等 ,结果表明 ,标题配合物结构在能量上是稳定的 ,作为结构单元而存在 . 展开更多
关键词 茂金属配合物 [(eat^5-C5H4r)Mo(CO)3]2 从头计算 电子结构
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R-(+)-2-(4-羟基苯氧基)丙酸的不对称合成 被引量:6
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作者 翁建全 高宗锦 +2 位作者 徐勃 丁成荣 谭成侠 《浙江工业大学学报》 CAS 北大核心 2009年第4期362-365,371,共5页
以具光活性的L-乳酸为起始原料,经酯化、磺酰化及醚化三步反应,醚化反应中发生构型反转,最终得到R-(+)-2-(4-羟基苯氧基)丙酸.在磺酰化反应中,以三乙胺作缚酸剂,TEBAC为催化剂,投料比为n(L-乳酸乙酯)∶n(对甲苯磺酰氯)∶n(三乙胺)=1∶1... 以具光活性的L-乳酸为起始原料,经酯化、磺酰化及醚化三步反应,醚化反应中发生构型反转,最终得到R-(+)-2-(4-羟基苯氧基)丙酸.在磺酰化反应中,以三乙胺作缚酸剂,TEBAC为催化剂,投料比为n(L-乳酸乙酯)∶n(对甲苯磺酰氯)∶n(三乙胺)=1∶1∶1.2,反应温度为0℃,反应时间为5 h,中间体S-(-)-2-(4-甲苯磺酰氧基)丙酸乙酯质量分数为98.0%,收率为96.5%.在醚化反应中,氮气氛下,以水作溶剂,投料比为n(对苯二酚)∶n(S-(-)-2-(4-甲苯磺酰氧基)丙酸乙酯)=1.2∶1,反应温度为30℃,反应时间为6 h,产物R-(+)-2-(4-羟基苯氧基)丙酸的质量分数为99.5%,收率为72.4%(以L-乳酸计),光学纯度97.9%.产物结构经1H NMR,IR和MS表征确认. 展开更多
关键词 L-乳酸 S-(-)-2-(4-甲苯磺酰氧基)丙酸乙酯 r-(%PLuS%)-2-(4-羟基苯氧基)丙酸 苯氧丙酸类除草剂
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不对称合成(R)-2-羟基-4-苯基丁酸乙酯的动力学 被引量:4
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作者 夏涛 任其龙 吴平东 《化工学报》 EI CAS CSCD 北大核心 2006年第1期46-51,共6页
采用10,11-二氢辛可尼定修饰的Pt/Al2O3催化体系,不对称加氢合成(R)-2-羟基-4-苯基丁酸乙酯,研究了各因素影响反应速率和光学收率的一般规律.根据推测的机理,建立了未修饰体系中加氢反应的本征动力学模型,结合实验数据选定了较佳的模型... 采用10,11-二氢辛可尼定修饰的Pt/Al2O3催化体系,不对称加氢合成(R)-2-羟基-4-苯基丁酸乙酯,研究了各因素影响反应速率和光学收率的一般规律.根据推测的机理,建立了未修饰体系中加氢反应的本征动力学模型,结合实验数据选定了较佳的模型.假设不对称加氢反应总速率包括反应物在催化剂表面修饰位上和未修饰位上两部分的加氢速率,建立了不对称加氢的动力学模型,经拟合得到参数并进行了验证和讨论. 展开更多
关键词 不对称加氢 (r)-2-羟基-4-苯基丁酸乙酯 本征动力学
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