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An effcient one-pot multi-component synthesis of 3,4,5-substituted furan-2(5H)-ones catalyzed by tetra-n-butylammonium bisulfate 被引量:5
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作者 Razieh Doostmohammadi Malek Taher Maghsoodlou +1 位作者 Nourallah Hazeri Sayyed Mostafa Habibi-Khorassani 《Chinese Chemical Letters》 SCIE CAS CSCD 2013年第10期901-903,共3页
A facile one-pot synthesis of 3,4,5-substituted furan-2(5H)-one derivatives from a three-component reaction of aniline derivatives, dialkylacetylenedicarboxylates and aromatic aldehydes under mild conditions using t... A facile one-pot synthesis of 3,4,5-substituted furan-2(5H)-one derivatives from a three-component reaction of aniline derivatives, dialkylacetylenedicarboxylates and aromatic aldehydes under mild conditions using tetra-n-butylammonium bisulfate as a catalyst has been developed. 展开更多
关键词 3 4 5-substituted furan-2(5H)-one Aniline derivative Dialkyl acetylenedicarhoxylate Aromatic aldehyde Tetra-n-butylammonium bisulfate
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Synthesis and Herbicidal Activity of Novel 5-Substituted Benzenesulfonylureas 被引量:4
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作者 WANG Mei-yi MU Xiao-li GUO Wan-cheng LI Yong-hong LI Zheng-ming 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2007年第6期674-678,共5页
Sulfonylurea herbicides have been widely used because of their low application rates, good crop sdeetivities and low mammalian toxicities. However, some sulfonylureas might persist unfavourably in the environment with... Sulfonylurea herbicides have been widely used because of their low application rates, good crop sdeetivities and low mammalian toxicities. However, some sulfonylureas might persist unfavourably in the environment with residual problems. In order to look for ecologically safer and environmentally benign sulfonylureas, and on keeping the pyrimidine ring being monosubstitated, 15 novd C5-monosubstituted benzenesulfonylurea compounds were synthesized. The structures of all the compounds synthesized were confirmed by demental analysis and ^1H NMR. Preliminary herbicidal activities of these new sulfonylurea compounds were determined by ALS screening ( in vitro) and pot bioassay experiments( in vivo). The herbicidal results show that some novel sulfonylureas are comparable to commercial Foramsulfuron and Monosulfuron. 展开更多
关键词 SULFONYLUREA 5-substituted phenyl ring Herbicidal activity
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Synthesis and anti-HBV activity of novel 5-substituted pyridin-2(1H)-one derivatives 被引量:2
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作者 Zhang, Yi Kai Lv, Zhi Liang +1 位作者 Niu, Chun Juan Li, Ke 《Chinese Chemical Letters》 SCIE CAS CSCD 2010年第3期290-292,共3页
Four novel 5-substituted pyridine-2(1H)-one derivatives were designed and synthesized by using addition-elimination reactions.The structures of these novelly synthesized compounds were verified by ~1H NMR,ESI-MS and s... Four novel 5-substituted pyridine-2(1H)-one derivatives were designed and synthesized by using addition-elimination reactions.The structures of these novelly synthesized compounds were verified by ~1H NMR,ESI-MS and single crystal X-ray diffraction.Furthermore,all four compounds(most notably compound 7a) were found to be highly efficient against hepatitis B virus (HBV) in cultured HepG2 2.2.15 cell,making them promising drug candidates for potential bioactive molecule against hepatitis B. 展开更多
关键词 5-substituted pyridin-2(1H)-one SYNTHESIS Crystal structure Anti-HBV activity
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Glycerol mediated synthesis of 5-substituted lH-tetrazole under catalyst free conditions 被引量:2
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作者 Kamalakar P.Nandre Jagdish K.Salunke +3 位作者 Jitendra P.Nandre Vijay S.Patil Amul U.Borse Sidhanath V.Bhosale 《Chinese Chemical Letters》 SCIE CAS CSCD 2012年第2期161-164,共4页
We have developed simple,cost effective and environmentally benign protocol for the synthesis of 5-substituted 1H-tetrazoles via[2,3]cycloaddition reaction from organic nitriles and sodium azide in glycerol under cata... We have developed simple,cost effective and environmentally benign protocol for the synthesis of 5-substituted 1H-tetrazoles via[2,3]cycloaddition reaction from organic nitriles and sodium azide in glycerol under catalyst free condition.The corresponding 5-substituted 1H-tetrazoles were obtained with good to excellent yields(68-95%). 展开更多
关键词 5-substituted 1H-tetrazole [3+2]Cycloaddition Nitriles Glycerol Catalyst free
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Zinc chloride catalyzed synthesis of 5-substituted 1H-tetrazoles under solvent free condition
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作者 Shahnaz Rostamizadeh Hamid Ghaieni +1 位作者 Reza Aryan Ali Amani 《Chinese Chemical Letters》 SCIE CAS CSCD 2009年第11期1311-1314,共4页
Zinc chloride is an efficient and safe catalyst in the [3 + 2] cycloaddition reaction of organic nitriles with sodium azide in solventless condition. The corresponding 5-substituted ^1H tetrazoles were obtained under... Zinc chloride is an efficient and safe catalyst in the [3 + 2] cycloaddition reaction of organic nitriles with sodium azide in solventless condition. The corresponding 5-substituted ^1H tetrazoles were obtained under mild conditions. This method can overcome disadvantages such as: the use of toxic metals and expensive reagents, drastic reaction conditions, water sensitivity and the presence of dangerous hydrazoic acid. 展开更多
关键词 5-substituted ^1H-tetrazoles Zinc chloride Sodium azide Solvent free
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Synthesis of 5-Substituted Hexahydro-1H-1, 4-Diazepine Analogues
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作者 Jing Shan SHEN Li Jun LEI +2 位作者 Hai Fang MAO Jian Feng LI Ru Yun JI 《Chinese Chemical Letters》 SCIE CAS CSCD 2001年第11期951-954,共4页
5-Substituted hexahydro-1H-1,4-diazepine analogues were synthesized starting from N,N'-dibenzyl-1, 2-ethylenediamine and methyl 2, 4-dibromide butyrate through nucleophilic substitution, reduction, chlorination, d... 5-Substituted hexahydro-1H-1,4-diazepine analogues were synthesized starting from N,N'-dibenzyl-1, 2-ethylenediamine and methyl 2, 4-dibromide butyrate through nucleophilic substitution, reduction, chlorination, debenzylation and amidation. Bioactivity tests showed that 9a had the highest agonist activity. 展开更多
关键词 5-substituted hexahydro-1H-1 4-diazepine analogues synthesis bioactivity
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STUDIES ON ORGANOPHOSPHORUS COMPOUNDS 69.A NOVEL SYNTHESIS OF 5-SUBSTITUTED 3-(1'-DIETHOXYPHOSPHORYLALKYL)-2-ISOXAZOLINES
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作者 Chao Zhong LI, Dong Biao ZHOU and Cheng Ye YUAN Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, 345 LingLing Lu, Shanghai 200032. 《Chinese Chemical Letters》 SCIE CAS CSCD 1993年第5期391-392,共2页
Additions of diethyl phosphite to α-nitroalkenes followed by the introduction of trimethylchlorosilane and an activated alkene, gave the corresponding title compounds via regioselective 1,3-dipolar cycloaddition in m... Additions of diethyl phosphite to α-nitroalkenes followed by the introduction of trimethylchlorosilane and an activated alkene, gave the corresponding title compounds via regioselective 1,3-dipolar cycloaddition in moderate yield. 展开更多
关键词 ISOXAZOLINES STUDIES ON ORGANOPHOSPHORUS COMPOUNDS 69.A NOVEL SYNTHESIS OF 5-substituted 3 DIETHOXYPHOSPHORYLALKYL
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Synthesis and biological evaluation of some novel-3-(5-substituted benzimidazol-2-yl)-5-arylisoxazolines 被引量:1
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作者 Vanga Malla Reddy Kunduru Ravinder Reddy 《Chinese Chemical Letters》 SCIE CAS CSCD 2010年第10期1145-1148,共4页
The synthesis of a new series of 3-(5-substituted benzimidazol-2-yl)-5-arylisoxazolines (6a-h) was achieved in excellent yields by the condensation of 1-(1H-benzimidazol-2-yl)-3-(substituted phenyl)prop-2-en-l... The synthesis of a new series of 3-(5-substituted benzimidazol-2-yl)-5-arylisoxazolines (6a-h) was achieved in excellent yields by the condensation of 1-(1H-benzimidazol-2-yl)-3-(substituted phenyl)prop-2-en-l-ones (5a-h) with hydroxylamine at room temperature. These 1-(1H-benzimidazol-2-yl)-3-(subsfituted phenyl)prop-2-en-l-ones (Sa-h) were obtained by the condensation of 2-acetyl benzimidazoles (4a-d) with different aromatic aldehydes, which in turn were obtained by the oxidation of 2-(α- hydroxy)ethyl benzimidazoles (3a-d) prepared by the reaction of o-phenylenediamines (lad) with ot-hydroxy propiohic acid 2. The synthesized compounds were characterized by their IR, ^1H NMR and MS analyses. These compounds were screened for their antibacterial and antifungal activity by standard methods and found some of them active. 展开更多
关键词 Benzimidazolyl-5-arylisoxazolines ANTIBACTERIAL Antifungal activity
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Theoretical Study on the Mechanism of a New Synthesis Reaction of 1,3,5-Substituted-1,2,4-triazoles by Carboxylic Acids,Amidines,and Hydrazines
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作者 王志玲 汪智娜 卢秀慧 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2018年第3期367-374,共8页
The synthesis of 1,3,5-substituted-1,2,4-triazoles from α-imino-3-pyridine formic acid,acetamidine and anisole hydrazine as a model reaction in this paper and the synthesis mechanism of 1,3,5-substituted-1,2,4-triazo... The synthesis of 1,3,5-substituted-1,2,4-triazoles from α-imino-3-pyridine formic acid,acetamidine and anisole hydrazine as a model reaction in this paper and the synthesis mechanism of 1,3,5-substituted-1,2,4-triazole compounds from carboxylic acids,amidines and hydrazines have been first investigated with the B3 LYP/6-311++G** method.According to the potential energy profile,it can be predicted that the course of the reaction consists of five reactions containing six elementary reactions.The α-imino-3-pyridine formic acid and acetamidine form first an intermediate product through a dehydration reaction; the intermediate product further combines with hydrogen ion to form a positive ion; the positive ion reacts with anisole hydrazine by a dehydration reaction to form another positive ion; then,followed by two isomerization reactions,the final reaction with the acetate ion(Ac-) produces the final product.The research results reveal the laws of synthesis reaction of 1,3,5-substituted-1,2,4-triazoles by the carboxylic acids,amidines,hydrazines and their derivatives on theoretical level.It provides the systemic theoretical basis for the synthesis,development and application of 1,3,5-substituted-1,2,4-triazole compounds. 展开更多
关键词 1 3 5-substituted-1 2 4-triazole synthetic reaction potential energy profile molar gibbs free energy of reaction(△rGm)-
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Synthesis of 5-Substituted 2, 9-Dimethyl-1,10-Phenanthroline Dialdehydes and Their Schiff Bases with Sulfur-Containing Amines
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作者 Zinia Jaman Mohammad R. Karim +2 位作者 Tasneem A. Siddiquee Aminul H. Mirza Mohamad A. Ali 《International Journal of Organic Chemistry》 2013年第3期214-219,共6页
Eight new Schiff bases of 5-nitro and 5-bromo-substituted 1,10-phenanthroline-2,9-dicarboxaldehydes with sulfur-containing amines, thiosemicarbazide, S-alkyl/aryl dithiocarbazates and 2-mercaptoaniline have been synth... Eight new Schiff bases of 5-nitro and 5-bromo-substituted 1,10-phenanthroline-2,9-dicarboxaldehydes with sulfur-containing amines, thiosemicarbazide, S-alkyl/aryl dithiocarbazates and 2-mercaptoaniline have been synthesized and characterized by a variety of spectroscopic methods. The condensation reactions of the dialdehydes with the amines were carried out both in the presence and absence of conc. sulfuric acid. A significant increase in yield of the Schiff bases was observed when the reactions were carried out in the presence of sulfuric acid. 展开更多
关键词 5-Nitro-1 10-PHENANTHROLINE DIALDEHYDE 5-Bromo-1 Schiff Bases S-Alkyl/Aryldithiocarbazates THIOSEMICARBAZIDE
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Antibacterial Activities of New Schiff Bases and Intermediate Silyl Compounds Synthesized from 5-Substituted-1,10-phenanthroline- 2,9-dialdehyde
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作者 Zinia Jaman Mohammad R. Karim +1 位作者 Korsi Dumenyo Aminul H. Mirza 《Advances in Microbiology》 2014年第15期1140-1153,共14页
Schiff bases are known to possess anticancer, antibacterial, antifungal, antitubercular, anti-inflammatory, antimicrobial and antimalarial properties. In this paper antibacterial studies against variety of plants and ... Schiff bases are known to possess anticancer, antibacterial, antifungal, antitubercular, anti-inflammatory, antimicrobial and antimalarial properties. In this paper antibacterial studies against variety of plants and human pathogenic bacteria with eight newly synthesized Schiff bases and several intermediate silyl compounds have been reported. The antibacterial activities of the synthesized compounds were primarily determined by paper disc diffusion method. The minimum inhibitory concentration (MIC) of each compound was also determined by tube dilution process. Seven different human pathogenic bacteria and eighteen different plant pathogenic bacteria were used for the antibacterial activity studies. While all synthesized compounds have shown significant antibacterial activity, one intermediate silyl compound has shown remarkably high antibacterial property. 5-substituted derivatives have shown relatively higher activity than non-substituted compounds. Polar substituent which increases hydrophilicity may have a positive impact on the antibacterial property. 展开更多
关键词 5-Nitro-1 10-PHENANTHROLINE DIALDEHYDE 5-Bromo-1 Schiff Bases S-Alkyl/Aryldithiocarbazates THIOSEMICARBAZIDE
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Dual-parameter Correlation Analysis of the Fluorescence Data of 1-Methyl-2-formyl-5-substituted Pyrrole(4-nitrophenyl)hydrazones
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作者 Roderick Hat Ying HE Xi Kui JIANG(Shanghai Institute of organic Chemistry,354 Feng-Lin Lu.Shanghai 200032) 《Chinese Chemical Letters》 SCIE CAS CSCD 1999年第6期499-502,共4页
By using 1-methyl-2-formyl-5 -Y-substituted pyrrole (4-nitrophenyl)hydrazones as a model for nitrogen-containing heterocyclic aromatic compounds, the emission wavelength [lambda(max(em))] values df their fluorescence ... By using 1-methyl-2-formyl-5 -Y-substituted pyrrole (4-nitrophenyl)hydrazones as a model for nitrogen-containing heterocyclic aromatic compounds, the emission wavelength [lambda(max(em))] values df their fluorescence spectra have been measured. Correlation results show that the Delta E-em values are mainly affected by polar effects, but spin-delocalizatin effects also exist. 展开更多
关键词 fluorescence spectra correlation analysis dual-parameter equation spin-delocalization effect polar effect 1-methyl-2-formyl-5-Y-substituted pyrrole (4-nitrophenyl)hydrazones
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Study on the Biological Activity of 3-Aroyl-5-substituted Thiophene Derivatives Based on the CoMFA Method 被引量:4
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作者 FENG Hui FENG Chang-Jun CAO Jing-Pei 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2020年第11期1978-1984,共7页
A three-dimensional quantitative structure-activity relationship(3 D-QSAR) study was conducted to analyze the A1 AR density(Bmax) of 56 3-aroyl-5-substituted thiophene derivatives(ASTDs) in human A1 Chinese hamster ov... A three-dimensional quantitative structure-activity relationship(3 D-QSAR) study was conducted to analyze the A1 AR density(Bmax) of 56 3-aroyl-5-substituted thiophene derivatives(ASTDs) in human A1 Chinese hamster ovary(hA1 CHO) membranes by the comparative molecular field analysis(CoMFA) method. A training set of 45 compounds was used to establish the predictive model, which was verified by the test set of 17 compounds containing template molecule and 5 newly designed molecules. The cross-validation(R2 cv) and non-cross-validation(R2) coefficients of the training set were 0.655 and 0.959, respectively. The model was used to predict the activities of the compounds of the training and test sets, and the results indicated that the models had strong stability and good prediction ability. According to model analysis, the contribution of steric and electrostatic fields was 51.4% and 48.6%, respectively. Based on the 3 D contour maps, five excellent ASTDs agonists were designed, which need to be further verified by biomedical experiments. 展开更多
关键词 3-aroyl-5-substituted thiophene derivatives(ASTDs) A1AR density(Bmax) three-dimensional quantitative structure-activity relationship comparative molecular field analysis
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基于CDK16/MYC探讨葛根芩连汤含药血清抑制糖酵解促进结直肠癌细胞5-氟尿嘧啶敏感性的作用机制
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作者 蔡蓉 王上 +3 位作者 程福晴 周燕萍 胡作为 李云海 《中国实验方剂学杂志》 北大核心 2026年第8期1-9,共9页
目的:基于细胞周期蛋白依赖性激酶16(CDK16)/MYC多效转录因子通路探究葛根芩连汤含药血清抑制糖酵解促进结直肠癌(CRC)5-氟尿嘧啶(5-FU)耐药细胞化疗敏感性的分子机制。方法:在(5%,10%,20%和30%)葛根芩连汤含药血清的干预下,运用细胞增... 目的:基于细胞周期蛋白依赖性激酶16(CDK16)/MYC多效转录因子通路探究葛根芩连汤含药血清抑制糖酵解促进结直肠癌(CRC)5-氟尿嘧啶(5-FU)耐药细胞化疗敏感性的分子机制。方法:在(5%,10%,20%和30%)葛根芩连汤含药血清的干预下,运用细胞增殖与活性检测(CCK-8)法检测葛根芩连汤对人结肠癌细胞HCT-116/5-FU细胞中5-FU敏感性的影响,选定后续5-FU和葛根芩连汤的实验浓度;采用5-乙炔基-2′-脱氧尿苷(EDU)染色和Annexin V-FITC/碘化丙啶(PI)双染法分别检测单独5-FU、单独葛根芩连汤及二者联合应用时HCT-116/5-FU细胞的增殖和凋亡水平变化,并用比色法测定葡萄糖消耗量、三磷酸腺苷(ATP)和乳酸产生的变化;蛋白免疫印迹法(Western blot)检测糖酵解相关蛋白、CDK16、MYC及磷酸化表达。免疫共沉淀(Co-IP)技术探究CDK16和MYC的蛋白相互作用关系,环己酰亚胺(CHX)处理检测过表达CDK16对MYC蛋白稳定性的影响。结果:与空白组比较,HCT-116细胞在加入2.5 mg·L^(-1)5-FU后细胞活力被显著抑制,且抑制效果随5-FU浓度升高而升高;而HCT-116/5-FU细胞在加入5 mg·L^(-1)5-FU后细胞活力才被明显抑制(P<0.05),选择5 mg·L^(-1)浓度造模。与单独5-FU组比较,当加入葛根芩连汤含药血清体积分数为5%后,HCT-116/5-FU的细胞活力被明显抑制(P<0.05),且抑制效果随葛根芩连汤含药血清浓度升高而升高,之后选用5%的葛根芩连汤含药血清处理。与空白组比较,5-FU组、葛根芩连汤组和5-FU+葛根芩连汤组细胞增殖能力均明显下降(P<0.05),且细胞凋亡水平也显著上调(P<0.01),但相较于5-FU组和葛根芩连汤组,5-FU+葛根芩连汤组抑制细胞增殖更为显著(P<0.01),且葡萄糖消耗量、ATP产生和乳酸产生水平下降也更为显著(P<0.01);此外,分别与空白组、5-FU组、葛根芩连汤组比较,5-FU+葛根芩连汤组对MYC及其磷酸化水平的抑制效果更为显著(P<0.01),且对糖酵解相关酶己糖激酶2(HK2)、3-磷酸肌醇依赖性蛋白激酶1(PDK1)、乳酸脱氢酶A(LDHA)和M2型丙酮酸激酶(PKM2)的抑制作用也显著增加(P<0.01)。同时,与5-FU组比较,5-FU+葛根芩连汤组中CDK16的表达下调(P<0.01),且MYC及其磷酸化蛋白的表达水平显著下降(P<0.01)。此外,与5-FU组比较,5-FU+葛根芩连汤组中MYC蛋白的稳定性随时间的变化明显降低(P<0.05),但被过表达CDK16所挽救(P<0.05)。结论:葛根芩连汤能显著增强HCT-116/5-FU细胞对5-FU的敏感性,其机制可能是葛根芩连汤通过抑制CDK16从而降低MYC介导的糖酵解。 展开更多
关键词 结直肠癌 5-氟尿嘧啶(5-FU)耐药 MYC 糖酵解 细胞周期蛋白依赖性激酶16(CDK16)
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中科发5号背景下东北粳稻育种目标与策略的思考
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作者 马兆惠 全成哲 +3 位作者 程海涛 杨衎劼 李欣蕊 吕文彦 《中国农业科学》 北大核心 2026年第5期927-936,共10页
中科发5号是李家洋院士团队利用分子设计育种理念培育的新品种。运用表型与分子标记选择相结合的方法,聚合了GL7(多拷贝)、GS3和GW5基因型组合,形成了水稻的细长籽粒,且含有高产的基因/QTL qSB2、qSB8、qSB10和SCM2等,以及携带稻瘟病抗... 中科发5号是李家洋院士团队利用分子设计育种理念培育的新品种。运用表型与分子标记选择相结合的方法,聚合了GL7(多拷贝)、GS3和GW5基因型组合,形成了水稻的细长籽粒,且含有高产的基因/QTL qSB2、qSB8、qSB10和SCM2等,以及携带稻瘟病抗性等位基因Pib、qBR10、Pi-ta和Ptr。基于此,该品种综合农艺性状表现出高产、多抗、品质优良等特点,在2014年位列中国十大主栽品种之列,已成为东北标志性品种。面对这一局面,未来东北粳稻应该以此为基准,实现超越。结合大米供需市场状况,育种目标应是以高产为基础的长粒香。具体产量目标为9500 kg·hm^(-2)以上,而实现这一目标的性状组配是株高95.0—105.0 cm、有效穗数375.0万—420.0万株/hm^(2)、穗粒数120.0粒以上、千粒重大于25.0 g;品质目标为粒长大于6.5 mm、长宽比大于2.8、整精米率达到审定标准、外观优良、食味80分以上、具有香味。除此之外,还要具有良好的适应性与抗性。为实现该目标,首先要加强辩证思维,要在实践中坚决淘汰大量不能达到育种目标的材料,同时,加强优良性状组配及其与当地栽培条件适应性的实践检验。在育种过程中,协调使用高产资源和长粒资源,加强复合杂交,同时优化育种过程,积极采用分子育种等现代育种技术。育种策略关键是要拓展具有广亲和性的籼粳亚种杂交稻恢复系的运用,特别是高产籼粳三系杂交稻的利用。由于高产三系杂交稻本身产量较高,其配子存在广泛重组,更有期望出现突破性类型。利用具有广亲和性的粳稻恢复系与长粒香型籼型杂交稻配组,可能是实现长粒香育种目标的最好策略,但还需进一步检验。 展开更多
关键词 粳稻 中科发5 辩证思维 育种目标 育种策略
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格拉瑟菌血清5型cpxAR双组分基因缺失株的生物学特性研究
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作者 徐引弟 王治方 +8 位作者 蔡旭旺 徐晓娟 张立宪 焦文强 朱文豪 李海利 游一 张家庆 雷亚楠 《河南农业科学》 北大核心 2026年第2期126-135,共10页
为研究cpxAR双组分基因在格拉瑟菌中的致病机制,同时筛选格拉瑟菌血清5型缺失弱毒株,构建格拉瑟菌血清5型临床分离株(GPS5)的cpxAR双基因缺失株(ΔcpxAR),并对缺失株的生长特性、生物膜形成能力、环境胁迫抗性及豚鼠致病力等生物学特性... 为研究cpxAR双组分基因在格拉瑟菌中的致病机制,同时筛选格拉瑟菌血清5型缺失弱毒株,构建格拉瑟菌血清5型临床分离株(GPS5)的cpxAR双基因缺失株(ΔcpxAR),并对缺失株的生长特性、生物膜形成能力、环境胁迫抗性及豚鼠致病力等生物学特性进行系统研究。结果表明,cpxAR基因缺失后,ΔcpxAR与亲本株GPS5相比,菌落形态和生长速率无明显差异,但生物膜形成能力明显减弱,对渗透压、热休克、氧化应激及碱性胁迫的抗性显著降低,对豚鼠的毒力也显著减弱。综上,cpxAR基因对GPS5的生长无明显调控作用,但对其生物膜形成、环境胁迫抗性及毒力均具有重要调控作用,为深入探究cpxAR双组分系统在格拉瑟菌中的生物学功能,以及筛选格拉瑟菌血清5型弱毒株奠定了基础。 展开更多
关键词 格拉瑟菌血清5 cpxAR基因缺失株 生长 生物膜 抗性 毒力
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热化学催化5-羟甲基糠醛连续氧化制备2,5-呋喃二甲酸的研究进展
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作者 王超 吴慨凡 +6 位作者 王忠铭 庄新姝 刘小春 冯颖 李连华 苗长林 罗文 《新能源进展》 北大核心 2026年第1期88-98,共11页
2,5-呋喃二甲酸(FDCA)可广泛应用于聚酯、增塑剂、医药、香料、农药等多个领域,也可用于生产可降解塑料、半芳香尼龙、不饱和树脂等短期可作为石油基高分子的改性剂,市场潜力巨大。5-羟甲基糠醛(HMF)是一种来源于生物质的可再生资源,可... 2,5-呋喃二甲酸(FDCA)可广泛应用于聚酯、增塑剂、医药、香料、农药等多个领域,也可用于生产可降解塑料、半芳香尼龙、不饱和树脂等短期可作为石油基高分子的改性剂,市场潜力巨大。5-羟甲基糠醛(HMF)是一种来源于生物质的可再生资源,可用于生产FDCA。简要概述了热化学催化氧化HMF的反应路径,系统总结了HMF催化反应体系的研究进展,分析提升催化剂活性的方法和当前面临的挑战,最后对催化剂的改性方向进行展望。可为HMF连续氧化制备FDCA的研究提供理论指导和参考,以促进生物质衍生物的应用。 展开更多
关键词 5-羟甲基糠醛 2 5-呋喃二甲酸 热化学催化 非贵金属催化剂
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g-C_(3)N_(5)基异质结光催化降解水中有机污染物的研究进展
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作者 刘亚利 赵亚龙 +3 位作者 汪鹏 康晓荣 荆肇乾 王祝来 《精细化工》 北大核心 2026年第4期743-756,共14页
富氮石墨氮化碳(g-C_(3)N_(5))凭借其窄带隙(~2.2 eV)、可吸收波长≤660 nm可见光的特性,在光催化领域展现出巨大的潜能。但单一g-C_(3)N_(5)半导体面临光生载流子复合率高、量子效率低等瓶颈问题。构建异质结调控界面电荷的迁移路径,... 富氮石墨氮化碳(g-C_(3)N_(5))凭借其窄带隙(~2.2 eV)、可吸收波长≤660 nm可见光的特性,在光催化领域展现出巨大的潜能。但单一g-C_(3)N_(5)半导体面临光生载流子复合率高、量子效率低等瓶颈问题。构建异质结调控界面电荷的迁移路径,是提升其光催化性能的有效手段。该文重点总结了g-C_(3)N_(5)基异质结的结构、电荷迁移路径及改性,归纳了其对水中染料、药物等有机污染物的光催化性能及反应机理。结合研究现状,提出了未来的研究方向应开发环境友好型无机半导体用于异质结的构建;建立“机器学习筛选-密度泛函理论计算深入分析-实验验证”模式,加速高性能异质结的研发与优化;运用高效精准的电荷检测技术揭示异质结结构及电荷转移机制;开展长期连续应用研究以评估光催化剂的稳定性和实际应用价值。 展开更多
关键词 g-C_(3)N_(5) 异质结 电荷转移机制 光催化 有机污染物
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乙酰丙酸改性对HZSM-5甲醇芳构化催化剂积炭行为的影响
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作者 李剑 乔永伟 +1 位作者 刘冲 杨丽娜 《石油学报(石油加工)》 北大核心 2026年第1期76-85,共10页
采用乙酰丙酸对HZSM-5甲醇芳构化催化剂进行酸处理改性,制得改性催化剂样品Lx-Z5(x为乙酰丙酸溶液质量分数,%)。为研究改性对催化剂积炭行为的影响,采用XRD、N_(2)吸附-脱附、NH_(3)-TPD、Py-FTIR和TGA/DTG等分析手段对新鲜的HZSM-5和Lx... 采用乙酰丙酸对HZSM-5甲醇芳构化催化剂进行酸处理改性,制得改性催化剂样品Lx-Z5(x为乙酰丙酸溶液质量分数,%)。为研究改性对催化剂积炭行为的影响,采用XRD、N_(2)吸附-脱附、NH_(3)-TPD、Py-FTIR和TGA/DTG等分析手段对新鲜的HZSM-5和Lx-Z5及失活的HZSM-5和Lx-Z5催化剂进行表征并评价其催化性能。结果表明,改性未破坏HZSM-5拓扑结构,但使其孔径、介孔孔体积增加,酸量及酸强度降低,Brønsted(B)/Lewis(L)酸量比(A_(B)/A_(L))增加,其中,L1.0-Z5催化剂样品的变化最显著。Lx-Z5催化剂的孔径、介孔孔体积及A_(B)/A_(L)的增加提升了苯-甲苯-二甲苯(BTX)选择性,孔径和介孔孔体积的增大、酸量及酸强度的降低减少了平均积炭速率、内积炭比例,提高了轻质积炭量,改性后再生性能更优。不同含量乙酰丙酸溶液改性中,L1.0-Z5样品的BTX选择性最高,使用寿命最长,平均积炭速率最低,容炭能力最强;相比HZSM-5催化剂,L1.0-Z5样品的BTX选择性、使用寿命分别增加5.55百分点和82 h,平均积炭速率降低0.36%/h。 展开更多
关键词 HZSM-5 乙酰丙酸改性 甲醇芳构化 寿命 积炭行为
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WO_(3)和TiO_(2)共掺V_(2)O_(5)复合薄膜的制备及其光电特性
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作者 王伟 李毅 +1 位作者 刘红薇 施张庆 《电子元件与材料》 北大核心 2026年第1期9-17,共9页
选用五氧化二钒、三氧化钨、二氧化钛粉末和过氧化氢溶液为原料,采用溶胶-凝胶法和后退火工艺在氟掺杂氧化锡导电玻璃基底上制备了三氧化钨和二氧化钛共掺五氧化二钒复合薄膜。通过场发射扫描电子显微镜、X射线衍射仪和X射线光电子能谱... 选用五氧化二钒、三氧化钨、二氧化钛粉末和过氧化氢溶液为原料,采用溶胶-凝胶法和后退火工艺在氟掺杂氧化锡导电玻璃基底上制备了三氧化钨和二氧化钛共掺五氧化二钒复合薄膜。通过场发射扫描电子显微镜、X射线衍射仪和X射线光电子能谱仪等表征了最佳配比下复合薄膜的表面形貌、结构和化学组成,利用分光光度计等测试手段分析了复合薄膜的光电特性。结果表明,在400~1200 nm波长范围内,复合薄膜在室温下的平均透过率为52.99%。当温度从室温升至400℃时,复合薄膜的电阻和透过率变化幅度分别达到83.7%和16.12%。在0~3.1 V的偏压下,复合薄膜的透过率随电压的增大而升高,在400~1200 nm波长范围内,平均透过率升高约12.21%;当偏压大于3.1 V时,复合薄膜的透过率随电压的增大而降低。经过多次高低温循环测试,该复合薄膜的光电特性具有较好的可逆热致光电性,在新型光电器件和传感器等领域展现出潜在应用前景。 展开更多
关键词 复合薄膜 V_(2)O_(5) TiO_(2) WO_(3) 溶胶-凝胶 光电特性
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