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Preparation and Electrochemical Properties of 3-Pyridinyl-6-aryl-1,2,4-triazolo [3,4-b][1, 3,4]thiadiazoles 被引量:3
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作者 TaiXIAO HuiXueLI +1 位作者 ChunXiaTAN MiaoCHEN 《Chinese Chemical Letters》 SCIE CAS CSCD 2005年第3期335-337,共3页
A series of 3-pyridinyl-6-aryl-l, 2, 4-triazolo[3, 4-b][1, 3, 4]thiadiazoles(PATT) were prepared, the structures were confirmed by IR and H NMR spectra. The results of cyclic 1 voltammetry measurements imply that all ... A series of 3-pyridinyl-6-aryl-l, 2, 4-triazolo[3, 4-b][1, 3, 4]thiadiazoles(PATT) were prepared, the structures were confirmed by IR and H NMR spectra. The results of cyclic 1 voltammetry measurements imply that all these compounds have a higher electron affinity (EA) than 2-(4-biphenyl)-5-(4-tert-butyl phenyl)-1, 3, 4-oxadiazole (PBD) which implies that PATT could be acting as better electron acceptors than widely used electron transporting material PBD. 展开更多
关键词 PREPARATION 3-pyridinyl-6-aryl-1 2 4-triazolo[3 4-b][1. 3 4]thiadiazoles electro- chemical properties.
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Phase Transfer Catalyzed Synthesis and Antibacterial Activity of Water-soluble S-Triazolo[3,4-b][1,3,4]thiadiazoles Containing Piperazine Group 被引量:1
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作者 Guo Qiang HU Wen Long HUANG Hai WANG 《Chinese Chemical Letters》 SCIE CAS CSCD 2005年第10期1309-1312,共4页
6/3-(4-Chlorophenyl)-s-triazolo[3, 4-b][1, 3, 4]thiadiazoles (2,a-e) and (Sa-e) were synthesized respectively by intermolecular cyclization of 5-aryl / 4-chlorophenyl-4-amino-3- mercapto-1, 2, 4-triazoles (la-e... 6/3-(4-Chlorophenyl)-s-triazolo[3, 4-b][1, 3, 4]thiadiazoles (2,a-e) and (Sa-e) were synthesized respectively by intermolecular cyclization of 5-aryl / 4-chlorophenyl-4-amino-3- mercapto-1, 2, 4-triazoles (la-e) and (4) with 4-chlorobenzoic acid / aryl acids, which were condensed with piperazine under phase transfer catalyst TBAB to yield the corresponding free bases of monopiperazine derivatives and followed to form water-soluble salts (3a-e) and (6a-e) with hydrochloric acid in good yields. The in vitro biological results showed that piperazine group conjugated with the above fused heterocycles played an important role in antibacterial activity. The structures of novel compounds were confirmed by IR, 'H NMR, MS and elemental analysis. 展开更多
关键词 s-Triazolo[3 4-b][1 3 4]thiadiazole PIPERAZINE WATER-SOLUBLE antibacterial activity.
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C–H Arylation using acyl thiourea ligands: Applications in the synthesis of 3,6-diaryl-[1,2,4]triazolo[3,4-b][1,3,4]thiadiazoles 被引量:1
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作者 Aamer Saeed Pervaiz Ali Channar +1 位作者 Qasir Iqbal Jamaluddin Mahar 《Chinese Chemical Letters》 SCIE CAS CSCD 2016年第1期37-40,共4页
Synthesis of a series of new 3,6-diaryl-[1,2,4]triazolo[3,4-b] [1,3,4]thiadiazoles(5a-o) was achieved by phophine free, C-H arylative cross-coupling of 6-aryl-[1,2,4]triazolo[3,4-b][1,3,4]thiadiazoles(4a-o)with su... Synthesis of a series of new 3,6-diaryl-[1,2,4]triazolo[3,4-b] [1,3,4]thiadiazoles(5a-o) was achieved by phophine free, C-H arylative cross-coupling of 6-aryl-[1,2,4]triazolo[3,4-b][1,3,4]thiadiazoles(4a-o)with suitably substituted iodoanilines using 1-(2-naphthoyl)-3-(4-bromophenyl)thiourea as a ligand.The requisite triazolothiadiazoles(4a-o) were obtained by the condensation of 4-amino-1,2,4-triazole-3-thiol(3) with suitably substituted aromatic acids in the presence of phosphoryl chloride. 展开更多
关键词 [1 2 4]Triazolo[3 4-b][1 3 4]thiadiazoles Acyl thiourea C-H arylative coupling N N-DIMETHYLACETAMIDE
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血管生成素样蛋白4通过调节成纤维细胞和内皮细胞功能影响糖尿病足进程
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作者 宋庆宏 吴楠 +5 位作者 史燕 崔洪雨 刘飞 刘汉冲 周宁 姚斌 《中国组织工程研究》 CAS 北大核心 2025年第25期5396-5402,共7页
背景:研究表明,血管因素对糖尿病足的发生具有重要影响。目的:探讨血管生成素样蛋白4在糖尿病足形成中的重要作用。方法:①对糖尿病足患者的基因表达谱数据进行生物信息学分析,找到关键基因。收集糖尿病足患者以及无糖尿病健康人的皮肤... 背景:研究表明,血管因素对糖尿病足的发生具有重要影响。目的:探讨血管生成素样蛋白4在糖尿病足形成中的重要作用。方法:①对糖尿病足患者的基因表达谱数据进行生物信息学分析,找到关键基因。收集糖尿病足患者以及无糖尿病健康人的皮肤标本进行苏木精-伊红染色、免疫组化染色以及qRT-PCR实验,检测血管生成素样蛋白4表达情况。②培养人永生化皮肤成纤维细胞系和原代人脐静脉内皮细胞,将2种细胞分别分为对照组和外源性补充血管生成素样蛋白4组,通过划痕实验以及CCK-8实验分别检测成纤维细胞的迁移能力和增殖能力,通过Ki67实验检测内皮细胞的增殖能力。结果与结论:①生信分析发现,血管生成素样蛋白4基因的下调可能是导致糖尿病足形成的关键基因。②苏木精-伊红染色结果显示,与正常皮肤相比,血管生成素样蛋白在糖尿病足皮肤内弱表达,且其mRNA水平相对表达量降低(P<0.01)。③划痕实验结果显示,与对照组相比,血管生成素样蛋白4组成纤维细胞迁移能力明显增强;CCK-8细胞增殖实验显示,血管生成素样蛋白4组成纤维细胞的吸光度值在24,48 h均高于对照组(P<0.01,P<0.001);提示血管生成素样蛋白4可增强高糖处理的成纤维细胞迁移及增殖能力。④Ki67实验结果显示,与对照组相比,血管生成素样蛋白4组内皮细胞Ki67阳性细胞数目明显多于对照组;CCK-8细胞增殖实验显示,血管生成素样蛋白4组内皮细胞的吸光度值在24,48 h均高于对照组(P<0.05,P<0.001)。(5)以上结果均提示血管生成素样蛋白4可增强高糖处理内皮细胞的增殖能力。 展开更多
关键词 血管生成素样蛋白4 成纤维细胞 血管内皮细胞 糖尿病足 生物信息学分析
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Preparation and Spectral Characterization of 3-Benzyl-6-aryl-1,2,4-triazolothiadiazoles 被引量:1
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作者 ZHANG Li xue ZHANG An jiang +3 位作者 CHEN Guang CHEN Fei yu JIANG Yi ping ZHANG Zi yi 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2002年第3期280-283,共4页
Benzyl 4 amino 5 mercapto 1,2,4 triazole reacted with aromatic acids in the presence of phosphorus oxychloride, yielding a series of new compounds, i.e. , 3 benzyl 6 aryl 1,2,4 triazolothiadiazoles, each of which has ... Benzyl 4 amino 5 mercapto 1,2,4 triazole reacted with aromatic acids in the presence of phosphorus oxychloride, yielding a series of new compounds, i.e. , 3 benzyl 6 aryl 1,2,4 triazolothiadiazoles, each of which has an active methylene at 3 position. The structures of all the title compounds were confirmed by elementary analysis, IR, 1H NMR and 13 C NMR spectra. 展开更多
关键词 3-Benzyl-6-aryl-1 2 4-triazolo[3 4-b][1 3 4]thiadiazoles PREPARATION Spectral characterization
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六方Al_(4)SiC_(4)弹性性质、电子结构和光学性质的第一性原理计算
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作者 刘运芳 张飞跃 +2 位作者 冯嘉怡 李文广 刘正堂 《原子与分子物理学报》 CAS 北大核心 2025年第3期166-172,共7页
采用基于密度泛函理论(DFT)的第一性原理计算方法系统地研究了Al_(4)SiC_(4)的晶体结构、弹性常数、电子结构和光学性质,并对结果进行了理论分析.计算得到的晶格常数和弹性常数均与实验值及其它计算值相符,并说明了六方Al_(4)SiC_(4)的... 采用基于密度泛函理论(DFT)的第一性原理计算方法系统地研究了Al_(4)SiC_(4)的晶体结构、弹性常数、电子结构和光学性质,并对结果进行了理论分析.计算得到的晶格常数和弹性常数均与实验值及其它计算值相符,并说明了六方Al_(4)SiC_(4)的晶体结构是稳定的;计算得到了六方Al_(4)SiC_(4)的体积、剪切、杨氏模量及泊松比与文献值一致,Al_(4)SiC_(4)的禁带宽度为1.076 eV.计算得到了六方Al_(4)SiC_(4)在(100)和(001)方向上的光学响应函数随光子能量的变化关系,包括复介电函数、复折射率、吸收光谱及反射光谱.在(100)和(001)方向上,计算得到其静态介电常数分别为7.74和8.96,折射率分别为2.78和2.99.计算结果可以为相关应用提供理论依据. 展开更多
关键词 Al_(4)SiC_(4) 电子结构 光学性质 第一性原理
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Synthesis and evaluation of in vitro antibacterial activity of novel 2,5-disubstituted-l,3,4-thiadiazoles from fatty acids 被引量:7
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作者 Mudasir R.Banday Abdul Rauf 《Chinese Chemical Letters》 SCIE CAS CSCD 2008年第12期1427-1430,共4页
A series of new 1-(alkenoyl/hydroxyalkenoyl)-4-benzoyl-thiosemicarbazides 2a-d and 2-benzamide-5-alkenyl/hydroxyalk- enyl-1,3,4-thiadiazoles 3a-d were synthesized from fatty acid hydrazides. Structure of all these c... A series of new 1-(alkenoyl/hydroxyalkenoyl)-4-benzoyl-thiosemicarbazides 2a-d and 2-benzamide-5-alkenyl/hydroxyalk- enyl-1,3,4-thiadiazoles 3a-d were synthesized from fatty acid hydrazides. Structure of all these compounds was confirmed by IR, IH NMR, Sac NMR, mass spectra and elemental analysis. The bioassay results indicate that some compounds 2e, 2d, 3e and 3d have good antibacterial activity. 展开更多
关键词 Aroylthiosemicarbazide 1 3 4-thiadiazolE Antibacterial activity
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Synthesis of 2-(N-formyl)-5-aryl/aryloxymethyl-1,3,4-thiadiazoles with potential bioactivity in PEG-400 被引量:1
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作者 Wang, Xi Cun Ding, Xiao Mei +2 位作者 Wang, Sheng Qing Chen, Xue Fei Quan, Zheng Jun 《Chinese Chemical Letters》 SCIE CAS CSCD 2010年第3期301-304,共4页
An environmental benign procedure for synthesis of 2-(N-formyl)-5-aryl/aryloxymethyl-1,3,4-thiadiazoles has been developed by reaction of 2-amino-5-aryl/aryloxymethyl-1,3,4-thiadiazoles with formic acid in PEG-400.The... An environmental benign procedure for synthesis of 2-(N-formyl)-5-aryl/aryloxymethyl-1,3,4-thiadiazoles has been developed by reaction of 2-amino-5-aryl/aryloxymethyl-1,3,4-thiadiazoles with formic acid in PEG-400.The key advantages of this protocol are the shorter reaction time,higher yields,lower cost,simple workup,and environment-friendly compared to conventional organic solvent reaction.The present method does not involve any hazardous organic solvent or catalyst. 展开更多
关键词 2-(N-Formyl)-5-aryl/aryloxymethyl-1 3 4-thiadiazoles 2-Amino-5-aryl/aryloxymethyl-1 PEG-400 Synthesis
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单轴应变对本征和N掺杂4H-SiC电子结构的影响
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作者 秦彦军 张建强 +5 位作者 杨慧雅 方峥 范晓珍 邝富丽 叶慧群 方允樟 《原子与分子物理学报》 CAS 北大核心 2025年第3期173-179,共7页
采用基于密度泛函理论的第一性原理方法,研究了单轴应变对本征和N掺杂4H-SiC电子结构的影响.研究表明应变可以有效调控本征和N掺杂4H-SiC的带隙,在拉应变作用下,带隙单调减小;而在压应变作用下,带隙先增大后减小,当压应变为-1%时,带隙... 采用基于密度泛函理论的第一性原理方法,研究了单轴应变对本征和N掺杂4H-SiC电子结构的影响.研究表明应变可以有效调控本征和N掺杂4H-SiC的带隙,在拉应变作用下,带隙单调减小;而在压应变作用下,带隙先增大后减小,当压应变为-1%时,带隙达到最大值.对态密度的分析可知本征和N掺杂4H-SiC的价带顶主要来自Si 3p和C 2p态电子,导带底主要来自Si 3p态电子,C 2p态和Si 3p态通过影响价带顶和导带底从而导致应变结构中带隙发生变化.通过Mulliken布局和差分电荷密度分析可知,随着晶格常数的增加Si原子向C原子和N原子转移的电荷减少,同时Si-C原子和Si-N原子之间的共价性减弱. 展开更多
关键词 4H-SIC 单轴应变 电子结构 第一性原理
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SYNTHESIS AND ANTIBACTERIAL ACTIVITY OF 3,6-DISUBSTITUTED S-TRIAZOLO[3,4-b]-1,3,4-THIADIAZOLES 被引量:1
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作者 Zi Yi ZHANG Xin CHEN Department of Chemistry,Lanzhou University,Lanzhou 730000 《Chinese Chemical Letters》 SCIE CAS CSCD 1991年第4期277-278,共2页
A series of 3,6-disubstituted s-triazolo[3,4-b]-1,3,4-thiadiazoles have been synthesized,whose structures were determined by elemental and spectral analyses;all the new compounds showed significant antibacterial activ... A series of 3,6-disubstituted s-triazolo[3,4-b]-1,3,4-thiadiazoles have been synthesized,whose structures were determined by elemental and spectral analyses;all the new compounds showed significant antibacterial activity. 展开更多
关键词 DMF 甲酰胺 SYNTHESIS AND ANTIBACTERIAL ACTIVITY OF 3 6-DISUBSTITUTED S-TRIAZOLO[3 4-b thiadiazoles
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Synthesis and bioactivity of a novel series of 3,6-disubstituted 1,2,4-triazolo[3,4-b]-1,3,4-thiadiazoles 被引量:1
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作者 Li, Ying Jun Liu, Li Jun +2 位作者 Jin, Kun Xu, Yong Ting Sun, Su Qin 《Chinese Chemical Letters》 SCIE CAS CSCD 2010年第3期293-296,共4页
A novel series of 3,6-disubstituted 1,2,4-triazolo[3,4-b]-1,3,4-thiadiazoles were synthesized by the condensation of 4-amino-5- [2-(4-chlorophenoxymethylbenzimidazole)-1-methylene]-3-mercapto-1,2,4-triazole with vario... A novel series of 3,6-disubstituted 1,2,4-triazolo[3,4-b]-1,3,4-thiadiazoles were synthesized by the condensation of 4-amino-5- [2-(4-chlorophenoxymethylbenzimidazole)-1-methylene]-3-mercapto-1,2,4-triazole with various(un)substituted aromatic acids in the presence of phosphorous oxychloride.These compounds were investigated for their inhibitory activity to E.coli methionine aminopeptidase(EcMetAP1).Some of the tested compounds showed significant inhibitory activity. 展开更多
关键词 Triazolo-thiadiazoles SYNTHESIS Bioactivity
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A novel series of 2,5-disubstituted 1,3,4-thiadiazoles as potential anticonvulsant agent 被引量:1
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作者 Harish Rajak Chinmay K.Behera +2 位作者 Raiesh S.Pawar Pradeep K.Singour Murli Dhar Kharya 《Chinese Chemical Letters》 SCIE CAS CSCD 2010年第10期1149-1152,共4页
In pursuit for better antiepileptic drug and the importance of semicarbazones and 2,5-disubstituted 1,3,4-thiadiazoles as anticonvulsant pharmacophore, a series of novel N-({5-[(6-methyl-l-benzofuran-3-yl)methyl]-l... In pursuit for better antiepileptic drug and the importance of semicarbazones and 2,5-disubstituted 1,3,4-thiadiazoles as anticonvulsant pharmacophore, a series of novel N-({5-[(6-methyl-l-benzofuran-3-yl)methyl]-l,3,4-thiadiazol-2-yl}carba- mothioyl)-2/3/4-substitutedbenzamide were designed, synthesized and evaluated for their anticonvulsant activity. The findings of the present studies confirmed that the pharmacophore model with four binding sites is crucial for anticonvulsant activity. Structure-activity relationships among synthesized compounds were also established. 展开更多
关键词 1 3 4-thiadiazoles SEMICARBAZONES Anticonvulsant activity
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Studies on Condensed Heterocyclic Compounds(Ⅲ)——Synthesis and Antibacterial Activity of 3-(4-Pyridyl)-6-Alkyl/Aromatic Heterocyclyl-s-Triazolo[3,4-b]-1, 3,4-Thiadiazoles and 1,4-Bis [6-(4-Pyridyl)-s-Triazolo [3,4-b]-1, 3,4-Thiadiazol-3-yl]-n-Butane 被引量:2
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作者 Zhang Ziyi, Chen Xin, Wei Lulin and Ma Zhaoli (Department, of Chemistry, Lanzhou University, Lanzhou) 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 1991年第2期129-133,共5页
In recent years, fused heterocycles have been reported to possess important properties in synthesis and pharmacology. Especially, s-triazolo, 3,4-thiadiazole derivatives have been attracting much attention for chemist... In recent years, fused heterocycles have been reported to possess important properties in synthesis and pharmacology. Especially, s-triazolo, 3,4-thiadiazole derivatives have been attracting much attention for chemists and pharmacologists because they show broad spectra of biological activities, such as antifungal, antibacterial, hy- 展开更多
关键词 s-Triazolo[3 4-b]-1 3 4-thiadiazoles SYNTHESIS Antibacterial activity
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One-pot synthesis of 2,5-disubstituted-1,3,4-thiadiazoles under ultrasonic irradiation 被引量:1
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作者 Ying Jun Li Ya Zhen Sun +4 位作者 Yong Ting Xu Kun Jin Li Ping Wen Ni Bo Hou Xiao Xiao Sun 《Chinese Chemical Letters》 SCIE CAS CSCD 2007年第9期1047-1048,共2页
A facile one-pot synthesis of 2,5-disubstituted-1,3,4-thiadiazoles was achieved by ultrasonic irradiation of a mixture of 1-naphthylacetyl chloride, NH4CNS, CH2Cl2 and PEG-400 for 1.5 h at 10–20 °C and subsequen... A facile one-pot synthesis of 2,5-disubstituted-1,3,4-thiadiazoles was achieved by ultrasonic irradiation of a mixture of 1-naphthylacetyl chloride, NH4CNS, CH2Cl2 and PEG-400 for 1.5 h at 10–20 °C and subsequent irradiation for 1.5 h in the presence of N-arylglycine hydrazides. This method requires short time and gives thiadiazoles in high yields. 展开更多
关键词 ONE-POT Ultrasonic irradiation 2 5-Disubstituted-1 3 4-thiadiazoles SYNTHESIS
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ACSL4介导铁死亡及在动脉粥样硬化性心血管病中的潜在作用
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作者 高洋 秦合伟 刘丹丹 《中国组织工程研究》 CAS 北大核心 2025年第6期1239-1247,共9页
背景:铁死亡是一种铁依赖性调节细胞死亡形式,其特征是铁依赖性脂质过氧化,长链酰基辅酶A合酶4参与脂质过氧化底物的形成进而导致铁死亡。近几年研究表明,长链酰基辅酶A合酶4介导铁死亡在动脉粥样硬化性心血管疾病中发挥关键作用。目的... 背景:铁死亡是一种铁依赖性调节细胞死亡形式,其特征是铁依赖性脂质过氧化,长链酰基辅酶A合酶4参与脂质过氧化底物的形成进而导致铁死亡。近几年研究表明,长链酰基辅酶A合酶4介导铁死亡在动脉粥样硬化性心血管疾病中发挥关键作用。目的:总结长链酰基辅酶A合酶4的结构功能和调控机制及其介导铁死亡的潜在分子机制,阐述长链酰基辅酶A合酶4驱动铁死亡在动脉粥样硬化、缺血性脑卒中和心肌梗死中的应用,以期为治疗动脉粥样硬化心血管疾病提供新的治疗策略。方法:在PubMed数据库检索自建库起至2023年8月收录的相关文献,以“atherosclerosis,ferroptosis,long-chain acyl-coenzyme A synthase 4,ACSL4,glutathione peroxidase 4,ischemic stroke,myocardial infarction,endothelial cell,smooth muscle cells,foam cell”为检索词,最终纳入76篇文献进行综述分析。结果与结论:①长链酰基辅酶A合酶4参与形成多不饱和脂肪酸的辅酶衍生物并将其插入磷脂,为铁死亡发生的核心机制脂质过氧化提供底物;②在长链酰基辅酶A合酶4表达的调节因子中,整合素α6β4、细胞内囊泡转运因子p115、锌脂蛋白A20负调控其表达,同时多种miR通过结合3′-UTR下调其表达,相反长链酰基辅酶A合酶4的表达上调大部分通过转录因子转录调控;③长链酰基辅酶A合酶4依赖性生成含有多不饱和脂肪酸的磷脂是脂质过氧化并执行铁死亡必不可少的必要条件,且长链酰基辅酶A合酶4与谷胱甘肽过氧化酶4作为铁死亡的正负调控因子相互制约,其具体机制仍待进一步研究;④长链酰基辅酶A合酶4介导铁死亡参与动脉粥样硬化、心肌梗死、缺血性脑卒中的病理机制,动脉粥样硬化中内皮细胞损伤与长链酰基辅酶A合酶4介导的铁死亡密切相关,但长链酰基辅酶A合酶4参与泡沫细胞形成、平滑肌细胞表型转化、钙化的研究尚未见报道;⑤长链酰基辅酶A合酶4作为铁死亡的生物标志物和潜在靶点成为研究热点,靶向长链酰基辅酶A合酶4抑制铁死亡可能成为治疗动脉粥样硬化性心血管疾病的新方向,而抑制长链酰基辅酶A合酶4的药物研究较少,未来还需进一步研究。 展开更多
关键词 动脉粥样硬化 长链酰基辅酶A合酶4 铁死亡 脂质过氧化 内皮细胞 泡沫细胞形成 平滑肌细胞 缺血性脑卒中 心肌梗死
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Preparation and Electrochemical Properties of 3-Phenyl-6-aryl- 1,2,4-triazolo[3,4-b][1,3,4]-thiadiazoles 被引量:2
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作者 CHENMiao XIAOTai +1 位作者 LIHui-xue LIUXiang 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2004年第6期810-812,共3页
关键词 Phenyl-6-aryl-1 2 4-triazolo[3 4-b][1 3 4]-thiadiazoles 8-HYDROXYQUINOLINE Electrochemical properties
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MgN_(4)掺杂石墨烯CO氧化催化活性的密度泛函研究
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作者 袁利 郑灵丹 +1 位作者 周慧颖 徐先燕 《原子与分子物理学报》 CAS 北大核心 2025年第2期57-62,共6页
鉴于镁卟啉所呈现的催化活性,采用密度泛函理论考察了MgN_(4)结构掺杂石墨烯的CO氧化催化活性.研究发现MgN_(4)掺杂石墨烯具有良好的结构稳定性,O_(2)优先吸附在金属活性位点且不易解离.其CO氧化以Eley-Rideal(ER)机理实现,决速步能垒仅... 鉴于镁卟啉所呈现的催化活性,采用密度泛函理论考察了MgN_(4)结构掺杂石墨烯的CO氧化催化活性.研究发现MgN_(4)掺杂石墨烯具有良好的结构稳定性,O_(2)优先吸附在金属活性位点且不易解离.其CO氧化以Eley-Rideal(ER)机理实现,决速步能垒仅为0.67 eV,与FeC_(3)、AlN_(4)掺杂石墨烯具有相当的催化活性.MgN_(4)掺杂石墨烯有望是一种具有潜在CO氧化催化活性的催化剂. 展开更多
关键词 MgN_(4)掺杂石墨烯 CO氧化 密度泛函理论
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Li掺杂对4H-SiC光电性质影响的理论研究 被引量:1
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作者 李萍 尹伟 +6 位作者 潘学聪 庞国旺 马亚斌 杨亚宏 杨菲宇 张盼 秦彦军 《原子与分子物理学报》 CAS 北大核心 2025年第2期151-158,共8页
采用基于密度泛函理论的第一性原理方法,计算了Li掺杂4H-SiC体系的电子结构及光学性质.结果表明,掺杂前后的4H-SiC均为间接带隙半导体,Li原子间隙掺杂后形成n型半导体,Li原子替位式掺杂体系的禁带中出现了杂质能级,降低了电子跃迁时所... 采用基于密度泛函理论的第一性原理方法,计算了Li掺杂4H-SiC体系的电子结构及光学性质.结果表明,掺杂前后的4H-SiC均为间接带隙半导体,Li原子间隙掺杂后形成n型半导体,Li原子替位式掺杂体系的禁带中出现了杂质能级,降低了电子跃迁时所需的能量;对电荷差分密度图的分析表明,Li原子失去电子,导致Li-C键和Li-Si键的共价性降低,以离子性为主;在可见光区域,相比于4H-SiC体系,掺杂体系的吸收率峰值均有所提高,其中Li间隙掺杂体系吸收带边最小,吸收率峰值最大,掺杂后的4H-SiC体系对红外、可见光、紫外均能够有所吸收,说明Li掺杂能够有效拓宽4H-SiC对光的响应范围. 展开更多
关键词 Li掺杂 4H-SIC 电子结构 光学性质 第一性原理
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双轴应变对NbSe_(2)/MoSi_(2)N_(4)肖特基势垒的调控
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作者 张宇哲 安梦雅 谢泉 《原子与分子物理学报》 CAS 北大核心 2025年第5期182-188,共7页
最近一种高质量的二维(Two-dimensional,2D)半导体材料MoSi_(2)N_(4)(MSN)在实验上被成功合成,具有优异的电气和机械性能.尽管最近有大量的研究致力于揭示MSN的材料特性,但到目前为止,对MSN的电接触物理特性的探索还比较少.在这项工作中... 最近一种高质量的二维(Two-dimensional,2D)半导体材料MoSi_(2)N_(4)(MSN)在实验上被成功合成,具有优异的电气和机械性能.尽管最近有大量的研究致力于揭示MSN的材料特性,但到目前为止,对MSN的电接触物理特性的探索还比较少.在这项工作中,构建了金属-半导体NbSe_(2)/MSN肖特基结并使用第一性原理密度泛函理论计算研究了该肖特基结的材料特性.发现NbSe_(2)/MSN接触具有超低肖特基势垒高度(Schottky barrier height,SBH),这有利于纳米电子学应用.SBH可以通过施加双轴应变的方式进行有效的调控.当施加拉伸应变时能实现NbSe_(2)/MSN肖特基结由p型肖特基接触转变为p型欧姆接触,而当施加较大的压缩应变时能实现p型肖特基接触和n型肖特基接触之间的转换.我们的研究结果为MSN的2D电触点的物理特性提供了见解,并将为设计基于MSN的2D纳米器件的高性能电触点提供关键的一步. 展开更多
关键词 MoSi_(2)N_(4) NbSe_(2) 肖特基结 欧姆接触
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Synthesis of 3-Aryl-6-benzoylamino-s-triazolo[3,4-b]-3,4-thiadiazoles
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《厦门大学学报(自然科学版)》 CAS CSCD 北大核心 1999年第S1期493-493,共1页
关键词 Synthesis of 3-Aryl-6-benzoylamino-s-triazolo[3 4-b thiadiazoles
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