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A simple and efficient synthesis of 2-substituted benzothiazoles catalyzed by H_2O_2/HCl 被引量:4
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作者 Hong Yun Guo Ji Chao Li You Le Shang 《Chinese Chemical Letters》 SCIE CAS CSCD 2009年第12期1408-1410,共3页
A simple and efficient procedure for the synthesis of substituted benzothiazoles through condensation of 2-aminothiophenol with aromatic aldehydes in the presence of H2O2/HCl system in ethanol at room temperature is d... A simple and efficient procedure for the synthesis of substituted benzothiazoles through condensation of 2-aminothiophenol with aromatic aldehydes in the presence of H2O2/HCl system in ethanol at room temperature is described. The target compounds have been characterized by ^1H NMR, ^13C NMR, IR and MS. Short reaction time, easy and quick isolation of the products, and excellent yields are the main advantages of this procedure. 展开更多
关键词 2-substituted benzothiazoles Heterocyclic compounds H2O2/HCl
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Ga(ClO_4)_3-catalyzed Reaction of 1,2-Diamines and α-Bromoketones:Synthesis of 2-Substituted Quinoxalines 被引量:1
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作者 JI Yun-fei CHEN Tang-ming +1 位作者 MAO Hai-feng ZOU Jian-ping 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2012年第4期642-646,共5页
Ga(ClO4)3-catalyzed reaction of 1,2-aryldiamines and α-bromoketones to afford 2-substituted quinoxalines in good yields is described.The reaction proceeded via grinding process with 10%(molar fraction) catalyst u... Ga(ClO4)3-catalyzed reaction of 1,2-aryldiamines and α-bromoketones to afford 2-substituted quinoxalines in good yields is described.The reaction proceeded via grinding process with 10%(molar fraction) catalyst under solvent-free conditions at room temperature.For unsymmetrical o-phenylenediamines bearing electron-withdrawing groups,regio-selective quinoxalines were obtained. 展开更多
关键词 Ga(ClO4)3 1 2-Aryldiamine α-Bromoketone 2-substituted quinoxaline Solvent-free reaction
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Synthesis of (2S,4S)-2-Substituted-3- (3-Sulfanylpropanoyl)-6- Oxohexahydropyrimidine-4-Carboxylic Acids as Potential Antihypertensive Drugs
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作者 Andrei Ershov Dmitry Nasledov +1 位作者 Igor Lagoda Valery Shamanin 《Journal of Materials Science and Chemical Engineering》 2015年第6期7-12,共6页
Proceeding from natural amino acid L-asparagine and commercially available aldehydes a stereoselective synthesis was developed of (2S,4S)-2-alkyl(aryl)-3-(3-sulfanylpropanoyl)-6-oxohexahy- dropyrimidine-4-carboxylic a... Proceeding from natural amino acid L-asparagine and commercially available aldehydes a stereoselective synthesis was developed of (2S,4S)-2-alkyl(aryl)-3-(3-sulfanylpropanoyl)-6-oxohexahy- dropyrimidine-4-carboxylic acids, potential antihypertensive drugs, inhibitors of the angiotensin converting enzyme. 展开更多
关键词 Synthesis of (2S 4S)-2-substituted-3- (3-Sulfanylpropanoyl)-6- Oxohexahydropyrimidine-4-Carboxylic ACIDS AS POTENTIAL ANTIHYPERTENSIVE DRUGS
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Eco-friendly synthesis of 2-substituted-2,3-dihydro-4(1H)-quinazolinones in water 被引量:6
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作者 Min Wang Ting Ting Zhang Zhi Guo Song 《Chinese Chemical Letters》 SCIE CAS CSCD 2011年第4期427-430,共4页
2-Substituted-2,3-dihydro-4(1H)-quinazolinones were synthesized in high yield by condensation of 2-anthranilamide with aromatic aldehydes or ketones in refluxing water without catalyst.This protocol has advantages o... 2-Substituted-2,3-dihydro-4(1H)-quinazolinones were synthesized in high yield by condensation of 2-anthranilamide with aromatic aldehydes or ketones in refluxing water without catalyst.This protocol has advantages of high yield,simple work-up and environmental friendly procedure. 展开更多
关键词 2 3-Dihydro-4(1H)-quinazolinone 2-Anthranilamide Aldehydes Ketones Synthesis in water
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Sulfamic acid as a reusable and green catalyst for efficient and simple synthesis of 2-substituted-2,3-dihydroquinazolin-4(1H)-ones in water or methanol 被引量:4
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作者 Amin Rostami Ashkan Tavakoli 《Chinese Chemical Letters》 SCIE CAS CSCD 2011年第11期1317-1320,共4页
A series of 2,3-dihydroquinazolin-4(1H)-ones have been synthesized in good to excellent yields through direct cyclocondensation of anthranilamide and aryl aldehydes or ketones in water or methanol under mild conditi... A series of 2,3-dihydroquinazolin-4(1H)-ones have been synthesized in good to excellent yields through direct cyclocondensation of anthranilamide and aryl aldehydes or ketones in water or methanol under mild conditions.The reaction was efficiently promoted by 10 mol%sulfamic acid(SA,H_2NSO_3H) and the catalyst could be recovered easily after the reactions and reused without evident loss of reactivity. 展开更多
关键词 Sulfamic acid Catalyst ANTHRANILAMIDE Aldehyde Ketone 2 3-Dihydroquinazolin-4(1H)-ones
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THE SYNTHESES OF 1,1,1-TRIFLUORO-2-SUBSTITUTED-PHENYL-2-PROPYL-3-^(14)C P- TOLUENESULFONATES
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作者 郭子丽 Arthur Fry 《Nuclear Science and Techniques》 SCIE CAS CSCD 1990年第4期239-242,共4页
1,1,1,-Trifluoro-2- substituted- phenyl- 2- propanols- 3- 14C were prepared from addition of methyl- 14C magnesium iodide to appropriate trifluoroacetophenone. These alcohols were converted into tosylatcs by reaction ... 1,1,1,-Trifluoro-2- substituted- phenyl- 2- propanols- 3- 14C were prepared from addition of methyl- 14C magnesium iodide to appropriate trifluoroacetophenone. These alcohols were converted into tosylatcs by reaction with n-butyllithium and then with p-toluenesulfonyl chloride. The yield, boiling point or melting point and pertinent spectral data of these compounds are reported. 展开更多
关键词 1 1- Trifluoro- 2- substituted- phenyl- 2- propanols- 3- 14C 1 1- Trifluoro- 2- substituted- phenyl- 2- propyl - 3- 14C P- toluenesulfonates Trifluoroacetophenones C- LABELLED compound
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Synthesis, Spectroscopic Characterization and Antimicrobial Activity of Some New 2-Substituted Imidazole Derivatives
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作者 Asmaa S. Salman Anhar Abdel-Aziem Marwa J. S. Alkubbat 《International Journal of Organic Chemistry》 2015年第1期15-28,共14页
The reaction of imidazole-2-thione derivative 1 with 2-chloro-N-p-tolylacetamide afforded the corresponding 2-(1HI-imidazol-2-ylthio)-N-p-tolylacetamide 2. Reaction compound 2 with different reagents such as p-chlorob... The reaction of imidazole-2-thione derivative 1 with 2-chloro-N-p-tolylacetamide afforded the corresponding 2-(1HI-imidazol-2-ylthio)-N-p-tolylacetamide 2. Reaction compound 2 with different reagents such as p-chlorobenzaldehyde and p-chlorophenyl diazonium chloride afforded the corresponding arylidene derivative 3 and hydrazone derivative 6. Reactions of 2 with carbon disulfide in dimethylformamide (DMF) in one equivalent potassium hydroxide afforded intermediate potassium sulphide salt 8, which treatment with dilute hydrochloric acid and phenacyl bromide afforded the corresponding 2-[p-tolylcarbamoyl]ethanedithioic acid 9 and 3-[benzo-ylmethylthio]-N-p-tolyl-3-thioxo-propaneamide 10. While the reaction 2 with carbon disulphide in the presence of two equivalent potassium hydroxide in DMF gave non-isolated potassium salt 11, which was allowed to react with halogenated compounds namely ethyl chloroacetate and methyl iodide afforded the corresponding 3, 3-bis[(ethoxycarbonyl)methylthio]-N-p-tolylacrylamide 12 and 3,3-bis-(methylthio)-N-p-tolylacrylamide 13 respectively. Reaction 2 with phenyl isothiocyanate in basic DMF yielded the intermediate potassium sulphide salt 18. Acidification 18 with dilute hydro-chloric acid afforded the corresponding thiocarbamoyl derivative 19. Treatment of intermediate 18 with methyl iodide, phenacyl bromide and ethylchloroacetate afforded the 3-anilino-3-(methylthio)-N-p-tolylacrylamide 20, 2-(1,3-thiazol-2(3H)-ylidene)-N-p-tolylacetamide 21 and 2-(4-oxo-3-phenyl-1,3-thiazolidin-2-ylidene)-N-p-tolylacetamide 22 respectively. The structure of the newly synthesized compounds has been confirmed by elemental analysis and spectra data. Synthesized compounds 2, 3, 6, 13, 15a, 15b, 17, 20, 21, 22 and 23 were screened for their antibacterial activities in vitro against Gram-positive (Staphylococcus aureus and Bacillus subtilis), Gram-negative (Pseudomonas aeuroginosa and Escherichia coli ) and antifungal activities against (Aspergillus fumigates, Syncephalastrum racemosum, Geotrichum candidum and Candida albicans). 展开更多
关键词 Imidazole-2-Thione α-Oxoketen DITHIOACETALS Thiocarbamyl THIAZOLE Antibacterial ANTIFUNGAL
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An Eco-friendly Method for Novel Scaffolds: Novel N2-Substituted Fused Pyrazolo (4',3':5,6) Pyrano (2,3-d) Pyrimidine Terminated by Hydroxy Group
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作者 Omar K. AI-Duaij 《Journal of Chemistry and Chemical Engineering》 2013年第9期821-828,共8页
Four components have been reacted in water and in the presence of N-morpholine yielded pyrnopyrazole as a simple substrate for novel N2-acyclonucleoside derivatives of fused pyranopyrazole. The sodium salt of fused py... Four components have been reacted in water and in the presence of N-morpholine yielded pyrnopyrazole as a simple substrate for novel N2-acyclonucleoside derivatives of fused pyranopyrazole. The sodium salt of fused pyranopyrazole reacted with halo alcohols led to the formation of new scaffolds from fused pyranopyrazole derivatives. All newly prepared compounds are characterized spectroscopically. 展开更多
关键词 Multi-component reactions eco-friendly method pyrazolo [2 3-c] pyran halo-alcohols acyclonucleosidation.
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Nicotinic Acid Activated Cp_(2)TiCl_(2) for Synergistic Catalysis of C-H Functionalization to Synthesize 2-(N-substituted amino)-1,4-Naphthoquinones
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作者 WANG Yunyun MA Caixia WANG Tao 《分子催化(中英文)》 北大核心 2025年第5期472-482,I0005,共12页
Cp_(2)TiCl_(2) as a Lewis acid precursor and nicotinic acid as a ligand have been used synergistically for the one-pot synthesis of 2-(N-substituted amino)-1,4-naphthoquinones.This method establishes a general strateg... Cp_(2)TiCl_(2) as a Lewis acid precursor and nicotinic acid as a ligand have been used synergistically for the one-pot synthesis of 2-(N-substituted amino)-1,4-naphthoquinones.This method establishes a general strategy for the functionalization and conversion of C-H bonds of 1,4-naphthoquinones into C-N bonds,providing an effective route to synthesize 2-(N-substituted amino)-1,4-naphthoquinone with high yield under mild conditions.Additionally,the synergistic catalytic mechanism was investigated by 1H NMR titration experiments and LC-MS analysis,with experimental results sufficiently and consistently supporting the proposed mechanism of the catalytic cycle. 展开更多
关键词 C-H functionalization 2-(N-substituted amino)-1 4-naphthoquinone Cp_(2)TiCl_(2) synergistic catalysis
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Insight into bay-/end-substituted perylene diimide and its S-scheme heterojunction for enhanced photocatalytic H_(2)O_(2) production under visible-light irradiation
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作者 Bo Zhang Kang Li +2 位作者 Renfu Li Shoufeng Wang Longtian Kang 《Journal of Materials Science & Technology》 2025年第3期257-268,共12页
Here,1D bis(N-carboxymethyl)peryleneimide(H_(2)PDI),0D 1,6,7,12-tetrachloro-bis(N-carboxymethyl)peryleneimide(4Cl-H_(2)PDI),and 2D 4Cl-H_(2)PDI/graphene quantum dot(4Cl-H_(2)PDI/GQD)nanostructures are synthesized and ... Here,1D bis(N-carboxymethyl)peryleneimide(H_(2)PDI),0D 1,6,7,12-tetrachloro-bis(N-carboxymethyl)peryleneimide(4Cl-H_(2)PDI),and 2D 4Cl-H_(2)PDI/graphene quantum dot(4Cl-H_(2)PDI/GQD)nanostructures are synthesized and carefully analyzed.The effect of bay-/end-substitution and S-scheme heterojunction of PDI-based materials as main catalysts on the photocatalytic H_(2)O_(2)evolution is first studied through the oxygen reduction reaction(ORR).Under the visible-light irradiation(>420 nm),4Cl-H_(2)PDI and 4Cl-H_(2)PDI/GQD as photocatalysts exhibit the∼7 and∼16 times H_(2)O_(2)evolution rate than H_(2)PDI(1059.6 vs.2484.0 vs.160.0μM g^(−1) h^(−1)),respectively.The systematical experiments reveal that 4Cl-H_(2)PDI and 4Cl-H_(2)PDI/GQD should prefer a two-step single-electron ORR process,while H_(2)PDI may involve a 4e-water oxidation and one-step 2e-ORR process.Further experiments confirm that the bay-substitution and GQD doping of H_(2)PDI can promote the generation,transportation,and separation of photogenerated electrons and holes,and prolong the carrier lifetime.This work provides insight into PDI-based photocatalytic H_(2)O_(2)production. 展开更多
关键词 Photocatalysis Oxygen reduction reaction H_(2)O_(2)evolution PERYLENEDIIMIDE S-scheme heterojunction
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Gallium-substituted self-pillared pentasil nanosheets combined with metal oxides for CO_(2)hydrogenation with enhanced selectivity of gasoline
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作者 Fengli Yuan Wenhui Li +5 位作者 Hong Yang Guangjin Hou Kuizhi Chen Junhui Yu Min Liu Xinwen Guo 《Journal of Energy Chemistry》 2025年第9期517-526,I0014,共11页
Carbon dioxide hydrogenation to gasoline can effectively alleviate the energy crisis and benefit the global environment.Owing to its orthogonally connected nanosheet configuration,large pore volume,and appropriate thi... Carbon dioxide hydrogenation to gasoline can effectively alleviate the energy crisis and benefit the global environment.Owing to its orthogonally connected nanosheet configuration,large pore volume,and appropriate thickness of single nanosheet,self-pillared pentasil(SPP)nanosheet zeolite is integrated with In_(2)O_(3)-ZrO_(2)as a tandem catalyst for CO_(2)hydrogenation to C_(5+)hydrocarbons.By substituting Al in the SPP framework with Ga,the acid strength of SPP is reduced,and acid density is increased,which favors the generation of C_(5+)hydrocarbons and enhances the cracking resistance of long-chain hydrocarbons.A maximum C_(5+)hydrocarbon selectivity of 82%was obtained on In_(2)O_(3)-ZrO_(2)/Ga-SPP(Si/Ga=100),which shows no deactivation after 200 h reaction time.Furthermore,introducing Pd into the In_(2)O_(3)-ZrO_(2)not only boosts CO_(2)conversion to 11%but also suppresses methane selectivity to below 1%.This study offers valuable insights into the design of highly active CO_(2)-to-gasoline catalysts by leveraging the distinctive structure and acidity of zeolites within the tandem catalyst systems. 展开更多
关键词 CO_(2)hydrogenation Self-pillared pentasil Gallium-substituted Tandem catalyst
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Stabilizing the solid-solution sodium storage in Cr-substituted Na_(3)V_(2)(PO_(4))_(3) cathode for aqueous sodium-ion batteries with long-term stability 被引量:1
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作者 Qinyan Jian Tinghong Gao +4 位作者 Wensheng Yang Xinhai Wang Lishan He Jiarui Liu Yunjun Ruan 《Journal of Energy Chemistry》 2025年第6期797-805,I0016,共10页
Aqueous sodium-ion batteries(ASIBs) offer significant advantages for energy storage on a large scale,attributed to their economical cost,secure operatio n,and eco-friend ly natu re.Among the leading cathode materials ... Aqueous sodium-ion batteries(ASIBs) offer significant advantages for energy storage on a large scale,attributed to their economical cost,secure operatio n,and eco-friend ly natu re.Among the leading cathode materials for ASIBs,Na_(3)V_(2)(PO_(4))_(3)(NVP) exhibits excellent structural stability and a high Na+diffusion coefficient,making it a promising option.However,the high solubility of vanadium-based materials in aqueous electrolytes engenders suboptimal cycling stability for Na_(3)V_(2)(PO_(4))_(3),constraining its application in ASIBs.Herein,the Cr-substituted Na_(3)V_(1.3)Cr_(0.7)(PO_(4))3@C(NV_(1.3)Cr_(0.7)P) cathode material was synthesized via a simple sol-gel method.It is found that Cr substitution reduces the cell parameters of NV_(1.3)Cr_(0.7)P,effectively reinforcing the crystal structure.Furthermore,NV_(1.3)Cr_(0.7)P alters the Na^(+)insertion/extraction mechanism,transforming the typical two-phase reaction between Na_(1)V_(2)(PO_(4))_(3)and Na_(3)V_(2)(PO_(4))3into continuous solid-solution reactions with stable intermediates.The Cr substitution diminishes the sodium-ion diffusion energy barrier in NV_(1.3)Cr_(0.7)P,leading to smoother Na+insertion and extraction processes.Consequently,NV_(1.3)Cr_(0.7)P exhibits impressive cycling stability,retaining 74.8% of its capacity after 5,000 cycles at a current density of 5 A g^(-1),along with an outstanding rate performance of 79,2% at 10 A g^(-1).This work elucidates the stable Na^(+)insertion/extraction processes in Cr-substituted NV_(1.3)Cr_(0.7)P,offering insights into the application of vanadium-based materials in aqueous sodium-ion batteries. 展开更多
关键词 Na_(3)V_(2)(PO_(4))_(3) Cr substitution Insertion/extraction mechanism Long-term cycling stability Aqueous sodium-ion battery
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An Efficient Synthesis of 2-Substituted Benzoxazoles via RuCl3.3H2O Catalyzed Tandem Reactions in Ionic Liquid 被引量:2
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作者 范学森 何艳 +2 位作者 王洋洋 张新迎 王键吉 《Chinese Journal of Chemistry》 SCIE CAS CSCD 2011年第4期773-777,共5页
An efficient synthesis of 2-substituted benzoxazoles through RuCl3·3H2O catalyzed, air oxidized tandem reactions of 2-aminophenols and aldehydes in [bmim]BF4 was developed. This synthetic strategy has such advant... An efficient synthesis of 2-substituted benzoxazoles through RuCl3·3H2O catalyzed, air oxidized tandem reactions of 2-aminophenols and aldehydes in [bmim]BF4 was developed. This synthetic strategy has such advantages as mild reaction conditions, cost-free oxidant, readily available starting materials, and recyclable catalyst and solvent. As an application, it was successfully used in the synthesis of the unreported 5-(benzoxazol-2-yl)-2'-deoxyuridines with potential biological activities. 展开更多
关键词 2-substituted benzoxazoles ruthenium chloride tandem reaction ionic liquids NUCLEOSIDE
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Cu(I)-Catalyzed Synthesis of 2-Substituted Benzimidazoles from 2-lodoanilines and Amides
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作者 Hua Yuan Yongxin Chen +2 位作者 Jinli Song Chunxia Chen Baohua Chen 《Chinese Journal of Chemistry》 SCIE CAS CSCD 2013年第10期1247-1249,共3页
A novel and efficient approach to the synthesis of 2-substituted benzimidazoles has been developed via CuI/DMEDA-catalyzed coupling reaction and post-cyclization with glacial acetic acid from readily available 2-iodoa... A novel and efficient approach to the synthesis of 2-substituted benzimidazoles has been developed via CuI/DMEDA-catalyzed coupling reaction and post-cyclization with glacial acetic acid from readily available 2-iodoanilines and amides. This method is suitable for the construction of a variety of benzimidazoles in moderate to good yields under short reaction times. 展开更多
关键词 2-substituted benzimidazoles CuI/DMEDA 2-iodoanilines AMIDES synthesis
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低O_(2)高CO_(2)贮藏环境延缓马铃薯块茎衰老的作用机制
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作者 田甲春 葛霞 +5 位作者 李守强 李梅 田世龙 张亚倩 程建新 李玉梅 《作物学报》 北大核心 2026年第1期262-278,共17页
为探讨低O_(2)高CO_(2)贮藏环境延缓马铃薯块茎的衰老机制,本研究以马铃薯陇薯17号为研究对象,通过测定营养品质、外观指标及生理指标,并结合贮藏中期(60 d)和末期(150 d)的转录组学分析,从表型水平和转录水平研究了马铃薯对低O_(2)高CO... 为探讨低O_(2)高CO_(2)贮藏环境延缓马铃薯块茎的衰老机制,本研究以马铃薯陇薯17号为研究对象,通过测定营养品质、外观指标及生理指标,并结合贮藏中期(60 d)和末期(150 d)的转录组学分析,从表型水平和转录水平研究了马铃薯对低O_(2)高CO_(2)贮藏环境的响应,揭示了马铃薯贮藏的分子调控机制。低O_(2)高CO_(2)贮藏环境延缓了马铃薯在低温贮藏期间淀粉含量的下降及还原糖含量的上升,抑制了薯块发芽和失水,保持了良好的薯皮色泽,抑制了PAL活性、POD活性的上升,并且对3种内源激素有积极的调控作用。与对照相比,贮藏中期共发现741个差异基因,其中上调基因378个,下调基因363个。贮藏至末期时,差异基因总数上升为1658个,其中上调基因为1211个,下调基因为447个。通过生物信息学分析发现,低O_(2)高CO_(2)贮藏环境显著调控与苯丙烷生物合成代谢、淀粉和蔗糖代谢、植物激素信号转导及MPAK信号转导相关的代谢途径。综上所述,本研究为马铃薯的气调贮藏提供了理论基础,为进一步研究分子机制提供了理论依据。 展开更多
关键词 马铃薯 低O_(2)高CO_(2) 延缓衰老 转录组学 代谢途径
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VUV/Fe^(2+)/Ox类芬顿体系对偶氮染料酸性红G的降解机理研究
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作者 王坤 陈伟 +5 位作者 唐玉朝 崔康平 伍昌年 朱先胜 孙海翔 黄显怀 《中国环境科学》 北大核心 2026年第2期785-796,共12页
构建了一种基于真空紫外(VUV)/Fe^(2+)/草酸(Ox)的新型无外源氧化剂类芬顿反应体系,并将其应用于偶氮染料酸性红G(ARG)的降解研究.结果表明,该体系可实现H_(2)O_(2)的动态释放,进而与Fe^(2+)形成类芬顿反应,且在较宽pH值范围内均能保持... 构建了一种基于真空紫外(VUV)/Fe^(2+)/草酸(Ox)的新型无外源氧化剂类芬顿反应体系,并将其应用于偶氮染料酸性红G(ARG)的降解研究.结果表明,该体系可实现H_(2)O_(2)的动态释放,进而与Fe^(2+)形成类芬顿反应,且在较宽pH值范围内均能保持高反应活性.结果表明:在ARG初始质量浓度为60mg/L、Fe^(2+)与Ox浓度分别为0.06和0.7mmol/L的条件下,VUV/Fe^(2+)/Ox体系对ARG的去除率在5min内即可达到96.2%,其降解过程符合准一级动力学模型.随着溶液初始pH值的升高,ARG去除率呈下降趋势,在pH=7时,一级速率常数k值仍可达0.454min⁻1,为pH=3时的69.6%,表明该体系在中性条件下仍能维持较高反应活性.反应初始5min内,体系中H_(2)O_(2)浓度逐渐上升至最高62.5µmol/L,随后缓慢下降,至9min时仍保持在51.8µmol/L.自由基捕获实验与EPR检测结果共同证实,羟基自由基(·OH)和超氧自由基(O_(2)^(·-))是该体系中的主要活性氧化物种.此外,水环境中常见的无机阴离子(HCO_(3)^(-)、NO_(3)^(-)、Cl^(-)、SO_(4)^(2-))均会对ARG降解产生不同程度的抑制作用.通过紫外可见吸收光谱及液相色谱-质谱联用(LC-MS)分析可知,降解过程中生成的活性氧(ROS)通过攻击ARG分子中的偶氮键和苯环结构,实现了染料的脱色与去除. 展开更多
关键词 VUV/Fe^(2+)/草酸体系 类芬顿反应 酸性红G 动态H_(2)O_(2)释放
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CO_(2)气氛条件下单基药的能量释放过程及规律研究
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作者 李成龙 丁亚军 肖忠良 《含能材料》 北大核心 2026年第2期122-129,共8页
针对发射药/超临界二氧化碳(SC-CO_(2))在弹射做功方面的应用潜力需求,通过与N_(2)环境对比开展了热分析、静态燃烧与密闭燃烧试验,研究了单基药在CO_(2)的热分解与燃烧特性。结果表明,CO_(2)环境明显抑制单基药热解过程,其活化能最大值... 针对发射药/超临界二氧化碳(SC-CO_(2))在弹射做功方面的应用潜力需求,通过与N_(2)环境对比开展了热分析、静态燃烧与密闭燃烧试验,研究了单基药在CO_(2)的热分解与燃烧特性。结果表明,CO_(2)环境明显抑制单基药热解过程,其活化能最大值较N_(2)环境升高15.53 kJ·mol^(-1);单基药在CO_(2)环境下燃烧时间显著延长,7 MPa时较N_(2)环境增加1729 ms,且SC-CO_(2)中单基药燃烧火焰呈现内白外淡红的特殊形貌;密闭燃烧时,液态CO_(2)相变吸热导致单基药点火延迟达12.20 ms,单基药在SC-CO_(2)环境下作用时间处于10^(-2) s量级。初始压力增加有助于提升单基药在SC-CO_(2)环境下能量释放速率。 展开更多
关键词 单基发射药 CO_(2)相变 能量释放 超临界二氧化碳(SC-CO_(2)) 火焰形貌
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废弃煤矿巷道CO_(2)“封存-利用”技术探索及转化效率研究
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作者 来兴平 雷彤 +3 位作者 张楠 胡添龙 介凯 刘旭超 《西安科技大学学报》 北大核心 2026年第1期15-26,共12页
为应对全球二氧化碳减排的需求,探索利用废弃煤矿地下空间实现CO_(2)封存与资源化利用的新路径,以提升其环境与资源效益。提出了包含捕集、封存、转化、分离系统的废弃煤矿巷道CO_(2)“封存-利用”一体化技术,基于几何相似理论与固体氧... 为应对全球二氧化碳减排的需求,探索利用废弃煤矿地下空间实现CO_(2)封存与资源化利用的新路径,以提升其环境与资源效益。提出了包含捕集、封存、转化、分离系统的废弃煤矿巷道CO_(2)“封存-利用”一体化技术,基于几何相似理论与固体氧化物电解池(SOEC)技术构建巷道反应硐室与实验室微型反应腔之间尺度映射关系,形成室内试验-井下应用的参数对应体系;通过开展恒电流共电解试验以及气相色谱对气体成分分析,系统揭示反应温度与CO_(2)/H_(2)O气体比例对CO_(2)转化效率的影响。结果表明:在保持A/V不变的条件下,巷道反应硐室尺寸为2.4 m×6 m×3.6 m,对应有效反应面积为384 m^(2);法拉第效率随着温度的升高呈现出“先下降后升高”的特征,随着CO_(2)/H_(2)O气体比例的增加而降低,CO_(2)转化率随着温度升高而显著提升,随着CO_(2)/H_(2)O气体比例增加而降低,在温度为850℃、气体比例CO_(2)∶H_(2)O=1∶1的共电解条件下,CO_(2)实现最优转化效率,转化率达72.22%,法拉第效率为61.77%。研究为实现废弃煤矿巷道CO_(2)封存与高值化利用提供了理论依据与技术支撑。 展开更多
关键词 废弃煤矿 固体氧化物电解池 CO_(2)/H_(2)O共电解 法拉第效率 CO_(2)转化率 相似理论
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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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2型糖尿病患者血浆外泌体微小RNA筛选及验证的研究
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作者 刘晓田 常高华 +7 位作者 何亚玲 任孝颖 江玉洁 蒋喜丽 侯建 李玉倩 张振中 王重建 《中国糖尿病杂志》 北大核心 2026年第1期2-7,共6页
目的筛选并验证T2DM患者相关血浆外泌体微小RNA(miRNA),评价差异miRNA对T2DM的预测能力。方法选取“河南农村队列”2020年驻马店现场随访的T2DM患者52例及同期非DM者52例,采用三阶段1:1匹配为发现集T2DM(DT2DM,n=5)组、发现集对照(DCon,... 目的筛选并验证T2DM患者相关血浆外泌体微小RNA(miRNA),评价差异miRNA对T2DM的预测能力。方法选取“河南农村队列”2020年驻马店现场随访的T2DM患者52例及同期非DM者52例,采用三阶段1:1匹配为发现集T2DM(DT2DM,n=5)组、发现集对照(DCon,n=5)组、验证集T2DM(VT2DM,n=15)组、验证集对照(VCon,n=15)组、靶向验证集T2DM(TT2DM,n=32)组和靶向验证集对照(TCon,n=32)组。采用外泌体miRNA测序技术对血浆外泌体miRNA进行测序,qRT-PCR检测关键差异miRNA水平,Spearman相关分析miRNA与FPG、FIns的相关性,Logistic回归分析miRNA对T2DM的影响,受试者工作特征(ROC)曲线评价关键miRNA对T2DM的预测价值。结果DT2DM组心率、FPG、外泌体浓度高于DCon组(P<0.05)。VT2DM组TG、FPG、FIns、腹型肥胖比例高于VCon组(P<0.05)。TT2DM组WC、TG、FPG、高血压病比例高于TCon组(P<0.05)。两阶段测序结果显示,DT2DM、VT2DM组外泌体关键miRNA miR-3120-5p表达水平均高于DCon、VCon组。Spearman相关分析显示,校正混杂因素后,miR-3120-5p与FPG呈正相关(r=0.311,P=0.016)。Logistic回归分析显示,校正混杂因素后,外泌体miR-3120-5p表达水平是T2DM的影响因素(OR 1.566,95%CI 1.177~2.057)。ROC曲线分析显示,外泌体miR-3120-5p诊断T2DM的曲线下面积为0.75,敏感度为81%,特异度为66%,截断值为7.28。结论miR-3120-5p在T2DM患者血浆外泌体中高表达,并对其具有良好的预测价值,但需在大样本多中心队列人群中进一步验证。 展开更多
关键词 糖尿病 2 外泌体 微小RNA 血浆 病例对照研究
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