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A New Class of Amide Ligands Enable Cu-Catalyzed Coupling of Sodium Methanesulfinate with (Hetero)aryl Chlorides 被引量:2
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作者 Dawei Ma Songtao Niu +4 位作者 Jinlong Zhao Xi Jiang Yongwen Jiang Xiaojing Zhang Tiemin Sun 《Chinese Journal of Chemistry》 SCIE CAS CSCD 2017年第11期1661-1664,共4页
((2S,4R)-4-Hydroxy-N-(2-methylnaphthalen-l-yl)pyrrolidine-2-carboxamide (HMNPC), an amide derived from 4-hydroxy-L-proline and 2-methyl naphthalen-l-amine, is a powerful ligand for Cu-catalyzed coupling of (he... ((2S,4R)-4-Hydroxy-N-(2-methylnaphthalen-l-yl)pyrrolidine-2-carboxamide (HMNPC), an amide derived from 4-hydroxy-L-proline and 2-methyl naphthalen-l-amine, is a powerful ligand for Cu-catalyzed coupling of (het- ero)aryl halides with sulfinic acid salts, allowing for first time the metal-catalyzed coupling of (hetero)aryl chlorides and NaSO2Me. A considerable number of (hetero)aryl chlorides worked well, providing the pharmaceutically im- portant (hetero)aryl methylsulfones in good to excellent yields. 展开更多
关键词 (hetero)aryl methylsulfone coupling reaction (hetero)aryl halides LIGAND copper
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Harnessing aryl hydrocarbon receptor dynamics:Unveiling therapeutic pathways in esophageal squamous cell carcinoma
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作者 Chun-Han Cheng Wen-Rui Hao Tzu-Hurng Cheng 《World Journal of Experimental Medicine》 2024年第4期1-5,共5页
This editorial discusses the insightful minireview by Rahmati et al.The minireview delves into the role of the aryl hydrocarbon receptor in the development and progression of esophageal squamous cell carcinoma,highlig... This editorial discusses the insightful minireview by Rahmati et al.The minireview delves into the role of the aryl hydrocarbon receptor in the development and progression of esophageal squamous cell carcinoma,highlighting its potential as a promising therapeutic target.The authors concisely summarize the current understanding of how aryl hydrocarbon receptor modula-tion influences immune responses and the tumor microenvironment,offering fresh perspectives on therapeutic strategies.This editorial aimed to emphasize the significance of these findings and their potential impact on future research and clinical practices for the management of esophageal squamous cell carcinoma. 展开更多
关键词 aryl hydrocarbon receptor Esophageal squamous cell carcinoma Immune modulation Therapeutic opportunities Tumor microenvironment
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Aryl hydrocarbon receptor dynamics in esophageal squamous cell carcinoma:From immune modulation to therapeutic opportunities
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作者 Mina Rahmati Hassan Moghtaderi +1 位作者 Saeed Mohammadi Ahmed Al-Harrasi 《World Journal of Experimental Medicine》 2024年第3期48-56,共9页
Esophageal squamous cell carcinoma(ESCC)is a substantial global health burden.Immune escape mechanisms are important in ESCC progression,enabling cancer cells to escape the surveillance of the host immune system.One k... Esophageal squamous cell carcinoma(ESCC)is a substantial global health burden.Immune escape mechanisms are important in ESCC progression,enabling cancer cells to escape the surveillance of the host immune system.One key player in this process is the Aryl Hydrocarbon Receptor(AhR),which influences multiple cellular processes,including proliferation,differentiation,metabolism,and immune regulation.Dysregulated AhR signaling participates in ESCC development by stimulating carcinogenesis,epithelial-mesenchymal transition,and immune escape.Targeting AhR signaling is a potential therapeutic approach for ESCC,with AhR ligands showing efficacy in preclinical studies.Additionally,modification of AhR ligands and combination therapies present new opportunities for therapeutic intervention.This review aims to address the knowledge gap related to the role of AhR signaling in ESCC pathogenesis and immune escape. 展开更多
关键词 Esophageal squamous cell carcinoma aryl hydrocarbon receptor Immune escape Tumor microenvironment IMMUNOSUPPRESSION Therapeutic targeting
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N-Arylation of azaheterocycles with aryl and heteroaryl halides catalyzed by iminodiacetic acid resin-chelated copper complex 被引量:5
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作者 Wu, Xiang Mei Wang, Yan 《Chinese Chemical Letters》 SCIE CAS CSCD 2010年第1期51-54,共4页
Iminodiacetic acid resin-chelated copper(Ⅱ) complex is effective in cross-coupling reactions between azaheterocycles and aryl or heteroaryl halides,providing N-arylated products in good to excellent yields.The copper... Iminodiacetic acid resin-chelated copper(Ⅱ) complex is effective in cross-coupling reactions between azaheterocycles and aryl or heteroaryl halides,providing N-arylated products in good to excellent yields.The copper catalyst is air stable and can be readily recovered and reused with minimal loss of activity for three runs. 展开更多
关键词 N-arylATION COPPER Azaheterocycle Iminodiacetic acid resin
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THE REACTION OF BENZOYL SUBSTITUTED HETEROCYCLIC KETENE AMINALS WITH ARYL AZIDES.A FACILE APPROACH TO SYNTHSIZE 1,5-DIARYL-4-(2-IMIDAZOLINYL)-1,2,3-TRIAZOLES 被引量:3
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作者 Zhi Tang HUANG Mei Xiang WANG Institute of Chemistry,Academia Sinica,Beijing,PR of China 《Chinese Chemical Letters》 SCIE CAS CSCD 1990年第1期5-8,共4页
Heterocyclic ketene aminals 1 react with aryl azides 2 to give the titled compounds 3,and in some cases also with the formation of fused heterocycles 4.
关键词 IMIDAZOLINYL THE REACTION OF BENZOYL SUBSTITUTED heteroCYCLIC KETENE AMINALS WITH aryl AZIDES.A FACILE APPROACH TO SYNTHSIZE 1 5-DIaryl-4 TRIAZOLES
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CuI/Proline-catalyzed N-Arylation of Nitrogen Heterocycles 被引量:2
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作者 Wei DENG Ye Feng WANG Chen ZHANG Lei LIU Qing Xiang GUO 《Chinese Chemical Letters》 SCIE CAS CSCD 2006年第3期313-316,共4页
Ma's CuI/proline procedure for the catalytic cross coupling between nitrogen heterocycles and aryl halides was markedly improved. The key finding was that K3PO4 was a much better base than K2CO3 for the reaction. Wit... Ma's CuI/proline procedure for the catalytic cross coupling between nitrogen heterocycles and aryl halides was markedly improved. The key finding was that K3PO4 was a much better base than K2CO3 for the reaction. With this new reaction condition the cross coupling with aryl iodides could be accomplished in 1,4-dioxane instead of DMSO. This reactin also could be carried out in DMF. Furthermore, the coupling yields under the new conditions are usually higher than in Ma's original methods. 展开更多
关键词 Cross coupling reaction CUI N-arylATION nitrogen heterocycle proline.
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Copper(Ⅰ)-catalyzed Synthesis of Aryl, Heteroaryl and Vinyl Sulfides in Aqueous Two-phase System
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作者 WANG Li-jin YUAN Yan-qin GUO Sheng-rong 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2011年第3期417-421,共5页
A fast and convenient C―S bond formation reaction was achieved catalyzed by CuI/L-proline in aqueous two-phase system providing a simple method for synthesis of aryl sulfides in good yields in short time.
关键词 C―S cross-coupling reaction CUI THIOL aryl halide Aqueous two-phase system
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Aryl hydrocarbon receptor nuclear translocator 2 as a prognostic biomarker and immunotherapeutic indicator for clear cell renal cell carcinoma
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作者 RENLONG ZHOU SHUANG LI XILIN XIAO 《BIOCELL》 SCIE 2023年第11期2397-2408,共12页
Background:In many cancer types,aryl hydrocarbon receptor nuclear translocator 2(ARNT2)has been found to be associated with tumor cell proliferation and prognosis.However,the role of ARNT2 in clear cell renal cell car... Background:In many cancer types,aryl hydrocarbon receptor nuclear translocator 2(ARNT2)has been found to be associated with tumor cell proliferation and prognosis.However,the role of ARNT2 in clear cell renal cell carcinoma(ccRCC)has not been completely elucidated.In this study,the potential role of ARNT2 in ccRCC development was characterized.Methods:A pan-cancer dataset(TCGA-TARGET-GTEx)was accessed from UCSC Xena Data Browser.ARNT2 expression in normal and tumor samples was compared.Univariate Cox regression was performed to evaluate the prognostic value of ARNT2.Single sample gene set enrichment analysis(ssGSEA)was used to estimate the enrichment of functional pathways and gene signatures.CIBERSORT and ESTIMATE methods evaluated the immune infiltration.The ARNT2 expression was determined in ccRCC tissue and cell lines using RT-qPCR and Western blot.Results:ARNT2 expression was significantly dysregulated in 23 out of 30 cancer types.Pan-cancer data revealed a strong correlation between ARNT2 expression and immune modulators,immune cell infiltration,and genomic alternations.In ccRCC patients,the low-ARNT2 expression group had higher immune infiltration,CD8 T cells,and programmed cell death ligand 1 expression,as well as higher enrichment score of immunotherapeutic predictors than those in the high-ARNT2 expression group.Low-ARNT2 expression group was more responsive to immunotherapy.Moreover,low ARNT2 expression was observed in ccRCC tissue and cell lines.Conclusions:Dysregulated ARNT2 expression is involved in cancer development and the modulation of the immune microenvironment.ARNT2 can be potentially used as a prognostic indicator and an immunotherapeutic indicator for ccRCC. 展开更多
关键词 Pan-cancer Clear cell renal cell carcinoma aryl hydrocarbon receptor nuclear translocator 2 Immune microenvironment IMMUNOTHERAPY
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Constitutive aryl hydrocarbon receptor facilitates the regenerative potential of mouse bone marrow mesenchymal stromal cells
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作者 Jing Huang Yi-Ning Wang Yi Zhou 《World Journal of Stem Cells》 SCIE 2023年第8期807-820,共14页
BACKGROUND Bone marrow mesenchymal stromal cells(BMSCs)are the commonly used seed cells in tissue engineering.Aryl hydrocarbon receptor(AhR)is a transcription factor involved in various cellular processes.However,the ... BACKGROUND Bone marrow mesenchymal stromal cells(BMSCs)are the commonly used seed cells in tissue engineering.Aryl hydrocarbon receptor(AhR)is a transcription factor involved in various cellular processes.However,the function of constitutive AhR in BMSCs remains unclear.AIM To investigate the role of AhR in the osteogenic and macrophage-modulating potential of mouse BMSCs(mBMSCs)and the underlying mechanism.METHODS Immunochemistry and immunofluorescent staining were used to observe the expression of AhR in mouse bone marrow tissue and mBMSCs.The overexpression or knockdown of AhR was achieved by lentivirus-mediated plasmid.The osteogenic potential was observed by alkaline phosphatase and alizarin red staining.The mRNA and protein levels of osteogenic markers were detected by quantitative polymerase chain reaction(qPCR)and western blot.After coculture with different mBMSCs,the cluster of differentiation(CD)86 and CD206 expressions levels in RAW 264.7 cells were analyzed by flow cytometry.To explore the underlying molecular mechanism,the interaction of AhR with signal transducer and activator of transcription 3(STAT3)was observed by co-immunoprecipitation and phosphorylation of STAT3 was detected by western blot.RESULTS AhR expressions in mouse bone marrow tissue and isolated mBMSCs were detected.AhR overexpression enhanced the osteogenic potential of mBMSCs while AhR knockdown suppressed it.The ratio of CD86+RAW 264.7 cells cocultured with AhR-overexpressed mBMSCs was reduced and that of CD206+cells was increased.AhR directly interacted with STAT3.AhR overexpression increased the phosphorylation of STAT3.After inhibition of STAT3 via stattic,the promotive effects of AhR overexpression on the osteogenic differentiation and macrophage-modulating were partially counteracted.CONCLUSION AhR plays a beneficial role in the regenerative potential of mBMSCs partially by increasing phosphorylation of STAT3. 展开更多
关键词 aryl hydrocarbon receptor Bone marrow mesenchymal stromal cells OSTEOGENESIS MACROPHAGE Signal transducer and activator of transcription 3 Interaction
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苯并芘通过芳香烃受体对心肌缺血再灌注损伤作用的研究 被引量:1
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作者 李国庆 叶钊飞 +2 位作者 张晨昊 邵怡辉 李平 《心肺血管病杂志》 CAS 2024年第5期510-516,536,共8页
目的:探究空气污染物苯并[a]芘[benzo(a)pyrene,BaP]对心肌缺血再灌注损伤(myocardial ischemia-reperfusion injury,IR)的影响,并进一步探索芳香烃受体(aromatic hydrocarbon receptor,Ahr)在这一过程中的关键作用。方法:本研究首先对C... 目的:探究空气污染物苯并[a]芘[benzo(a)pyrene,BaP]对心肌缺血再灌注损伤(myocardial ischemia-reperfusion injury,IR)的影响,并进一步探索芳香烃受体(aromatic hydrocarbon receptor,Ahr)在这一过程中的关键作用。方法:本研究首先对C57BL/6J小鼠进行Bap气道给药(15mg/kg),随后构建心肌缺血再灌注损伤模型。我们通过Evans Blue/TTC染色,TUNEL染色,超声心动图和Masson染色对实验组和对照组小鼠的心肌损伤程度进行评估,并通过RT-PCR及免疫荧光共定位探究Ahr介导的潜在作用机制。结果:与对照组相比,实验组小鼠表现出更为严重的心肌损伤。RTPCR结果表明,BaP暴露后,Ahr下游靶基因及炎症相关基因mRNA表达水平明显升高。免疫荧光染色结果显示,Ahr在心脏巨噬细胞上呈现出明显的表达。结论:空气污染物BaP可通过激活Ahr,促进巨噬细胞分泌炎症因子,加重心肌缺血再灌注损伤。 展开更多
关键词 苯并芘 芳香烃受体 心肌缺血再灌注损伤 巨噬细胞
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高铁区位对中国异地投资的影响与异质性评价 被引量:1
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作者 焦敬娟 马王钰青 王伟 《地理科学》 CSSCI CSCD 北大核心 2024年第3期400-410,共11页
作为一种特殊的跨区域重大基础设施,高速铁路(下文简称为“高铁”)开通减少沿线企业面临的要素约束,降低企业间的信息不对称和代理成本,促进沿线地区资本流动,影响城市间的异地投资。依托2008-2017年中国上市公司新建投资决策数据,以高... 作为一种特殊的跨区域重大基础设施,高速铁路(下文简称为“高铁”)开通减少沿线企业面临的要素约束,降低企业间的信息不对称和代理成本,促进沿线地区资本流动,影响城市间的异地投资。依托2008-2017年中国上市公司新建投资决策数据,以高铁所引致的连通性和可达性等区位条件变化为切入,分析和评价高铁对异地投资的影响及其空间异质性。研究发现:①东部地区连通性提升更快,西部地区可达性改善更显著;巨特大城市与中小城市的可达性和连通性的绝对差距不断拉大。②异地投资主要流向东部地区和巨特大城市,但地区差异呈缩小态势。③高铁区位对异地投资有显著正向影响,并且可达性的影响程度大于连通性的影响。④高铁区位对不同地区、不同规模城市异地投资的影响呈现差异性,连通性促进资金向东部地区和巨特大城市流动,可达性则能够显著提升西部地区及小城市对异地投资的吸引。 展开更多
关键词 高铁区位 重大基础设施 连通性 异地投资 空间异质性
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Numerical Simulation for Enhancing Performance of MoS2 Hetero-Junction Solar Cell Employing Cu2O as Hole Transport Layer
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作者 Md. Ferdous Wahid Ushna Das +3 位作者 Bidesh Kumer Paul Shuvo Paul Md. Nuralam Howlader Md. Sazedur Rahman 《Materials Sciences and Applications》 2023年第9期458-472,共15页
The paper reported the design and thorough analysis of a thin-film solar cell (TFSC) based on molybdenum disulfide (MoS<sub>2</sub>) with an integrated Copper(I) Oxide (Cu<sub>2</sub>O) hole tr... The paper reported the design and thorough analysis of a thin-film solar cell (TFSC) based on molybdenum disulfide (MoS<sub>2</sub>) with an integrated Copper(I) Oxide (Cu<sub>2</sub>O) hole transport layer (HTL), employing the one-dimensional Solar Cell Capacitance Simulator (SCAPS-1D) software. By varying crucial parameters such as absorber layer thickness, doping density, and bulk defect density, as well as HTL thickness, doping concentration, and electron affinity, defect density at ZnO/absorber and absorber/Cu<sub>2</sub>O interfaces, and operating temperature, we explored key photovoltaic measures including open circuit voltage (Voc), short-circuit current density (Jsc), fill-factor (FF), and power conversion efficiency (PCE) of the hetero-junction solar cell. The study demonstrated an efficiency of 18.87% for the MoS<sub>2</sub> solar cell without HTL, while the proposed solar cell (SC) utilizing Cu<sub>2</sub>O HTL and optimized device structure exhibited a remarkable PCE of 26.70%. The outcomes derived from the present study offer valuable insights for the progress of a highly efficient and economically viable MoS<sub>2</sub> hetero-junction TFSC. 展开更多
关键词 Solar Cell Thin Film SCAPS-1D hetero-Junction HTL Defect Density
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双重动态键协同增强聚芳醚腈复合材料的制备及性能研究
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作者 何星 杨宇浓 +5 位作者 吴静菊 王犁 来婧娟 颜贵龙 李振宇 武元鹏 《功能材料》 CAS CSCD 北大核心 2024年第10期10180-10188,共9页
通过动态硼氧键和氢键的共价/非共价协同增强的方法制备了动态硼氧键交联聚芳醚腈(PEN-COOH-B_(3)O_(3))/聚乙烯吡咯烷酮(PVPON)复合材料。并用万能拉伸试验机,差示扫描量热仪等仪器手段对复合材料的力学性能,形状记忆功能,热稳定性,自... 通过动态硼氧键和氢键的共价/非共价协同增强的方法制备了动态硼氧键交联聚芳醚腈(PEN-COOH-B_(3)O_(3))/聚乙烯吡咯烷酮(PVPON)复合材料。并用万能拉伸试验机,差示扫描量热仪等仪器手段对复合材料的力学性能,形状记忆功能,热稳定性,自愈合性能和循环回收性能进行了一系列表征与研究。利用PEN-COOH-B_(3)O_(3)/PVPON之间的氢键作用制备的复合材料强度可达102.5 MPa,弹性模量达3455.7 MPa,玻璃化转变温度T_(g)达180.3℃。动态硼氧键的加入使得复合材料具有优异的溶剂辅助自修复和回收性能,在经过常温(25℃)自愈合24 h后愈合效率达98.7%,经历五次循环回收力学性能无损失。同时,利用动态硼氧键的刺激响应性,该复合材料表现出良好的形状记忆行为。 展开更多
关键词 聚芳醚腈 聚乙烯吡咯烷酮 动态硼氧键 形状记忆 可回收
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水资源约束下科技创新对农业高质量发展的异质影响及作用路径研究
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作者 张南 修长百 张旭光 《科学管理研究》 CSSCI 北大核心 2024年第3期118-125,共8页
对于水资源不足的生态脆弱区,面对新时期农业高产出和高质量发展的目标要求,厘清不同水资源约束下科技创新对农业发展质量的影响及互动关系,对于降低生态资源要素制约、提高科技创新驱动的匹配度与贡献度,提升地区农业高质量发展水平具... 对于水资源不足的生态脆弱区,面对新时期农业高产出和高质量发展的目标要求,厘清不同水资源约束下科技创新对农业发展质量的影响及互动关系,对于降低生态资源要素制约、提高科技创新驱动的匹配度与贡献度,提升地区农业高质量发展水平具有重要意义。基于2008-2021年内蒙古12个盟市面板数据,在客观测度不同地区农业高质量发展水平的基础上,引入受限因变量模型和广义矩估计模型系统探讨不同水资源约束下科技创新对农业高质量发展的异质影响效应及作用路径。结果表明:①不同水资源约束下科技创新均可显著促进地区农业高质量发展,且在强水资源约束区科技创新所发挥的农业高质量发展促进作用为弱水资源约束区的5倍;②科技创新对农业高质量发展的影响具有时滞性,且科技创新人才的影响效应也较为显著;③科技创新主要通过提升水资源利用的“节水”和“增效”作用路径推动农业高质量发展。据此,提出加强农业科技创新投入、建立针对不同水资源约束强度的差异化科技创新支持政策,通过科技创新手段消除“短板效应”、强化水资源保障能力,推动农业高质量发展。 展开更多
关键词 水资源约束 科技创新 农业高质量发展 异质效应
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碳交易政策的就业效应及其作用机制——基于3064家A股上市公司的证据
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作者 谭志雄 刘胜男 《工业技术经济》 CSSCI 北大核心 2024年第8期100-109,共10页
在推动绿色发展和低碳转型过程中,日趋严格的环境规制对就业带来的影响愈发引人关注。本文利用中国沪深股市A股上市企业的数据,使用双重差分方法实证检验碳交易政策对企业就业的影响,并探讨这一政策对就业市场的潜在影响途径。研究结果... 在推动绿色发展和低碳转型过程中,日趋严格的环境规制对就业带来的影响愈发引人关注。本文利用中国沪深股市A股上市企业的数据,使用双重差分方法实证检验碳交易政策对企业就业的影响,并探讨这一政策对就业市场的潜在影响途径。研究结果表明,碳交易政策对企业的就业水平具有正向作用,主要通过产出效应和要素替代效应影响就业水平;碳交易政策的就业提升作用对不同的企业存在显著的异质性,碳交易政策能够显著地促进年轻企业和企业所有制为国有、民营的企业就业。本文将碳交易政策和就业问题纳入同一分析框架,为实现碳中和目标与积极促进就业提供有益参考。 展开更多
关键词 碳交易 就业水平 双重差分法 产出效应 要素替代效应 异质性 环境规制 协同效应
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可见光诱导6H-苯并[c]苯并吡喃及二氢菲啶衍生物的合成
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作者 杨森 胡浩 陈铭 《常州大学学报(自然科学版)》 CAS 2024年第4期1-7,共7页
开发出了可见光诱导的分子内C—H芳基化反应,合成了一系列6H-苯并[c]苯并吡喃及二氢菲啶衍生物。合成得到的产物用^(1)H NMR以及^(13)C NMR进行结构表征。与传统方法相比,该方法利用清洁可再生的光能驱动化学反应,避免了高温、高压等严... 开发出了可见光诱导的分子内C—H芳基化反应,合成了一系列6H-苯并[c]苯并吡喃及二氢菲啶衍生物。合成得到的产物用^(1)H NMR以及^(13)C NMR进行结构表征。与传统方法相比,该方法利用清洁可再生的光能驱动化学反应,避免了高温、高压等严格的反应条件。此外,该方法具有原料易得、底物适用范围广泛、反应条件温和、操作简单等优点。 展开更多
关键词 可见光诱导 C—H芳基化 6H-苯并[c]苯并吡喃 二氢菲啶 杂环化合物
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钯催化合成N-芳基-γ-胺基-γ-丁内酰胺类化合物
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作者 鲍峰玉 刘兴源 +1 位作者 张婉 李志 《合成化学》 CAS 2024年第8期705-710,共6页
γ-丁内酰胺是很多具有生物活性、药物活性化合物的核心结构单元。已报道的由过渡金属催化,直接合成N-芳基-γ-胺基-γ-丁内酰胺类化合物的反应,存在必须使用过氧化物、操作不便的局限性。以10%(物质的量分数,下同)Pd/C为催化剂,将芳香... γ-丁内酰胺是很多具有生物活性、药物活性化合物的核心结构单元。已报道的由过渡金属催化,直接合成N-芳基-γ-胺基-γ-丁内酰胺类化合物的反应,存在必须使用过氧化物、操作不便的局限性。以10%(物质的量分数,下同)Pd/C为催化剂,将芳香胺和N-甲基吡咯烷酮在空气气氛下的二甲苯中于100℃反应24 h得到N-芳基-γ-胺基-γ-丁内酰胺类化合物(3a~3g),产率高达91%。经过核磁氢谱、碳谱和高分辨质谱分析,产物的结构得到确证。 展开更多
关键词 催化 合成 芳香胺 N-甲基吡咯烷酮 氧化胺化 γ-丁内酰胺
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叔丁基化芳基磷酸酯和碳微球对PC/ABS性能的影响
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作者 刘小忠 徐娟 李湘 《工程塑料应用》 CAS CSCD 北大核心 2024年第7期162-166,185,共6页
为研究叔丁基化芳基磷酸酯(TBP)和碳微球(CMS)对聚碳酸酯/丙烯腈-丁二烯-苯乙烯(PC/ABS)塑料性能的影响,通过熔融挤出法制备了PC/ABS/TBP/CMS复合材料,利用水平垂直燃烧试验仪、锥形量热仪、热重分析仪和万能材料试验机等分析了复合材... 为研究叔丁基化芳基磷酸酯(TBP)和碳微球(CMS)对聚碳酸酯/丙烯腈-丁二烯-苯乙烯(PC/ABS)塑料性能的影响,通过熔融挤出法制备了PC/ABS/TBP/CMS复合材料,利用水平垂直燃烧试验仪、锥形量热仪、热重分析仪和万能材料试验机等分析了复合材料的阻燃性能、热性能和物理性能。结果表明,TBP可以提高PC/ABS的阻燃性能,但会降低力学性能和尺寸稳定性,在PC/ABS中加入质量分数12%的TBP,PC/ABS/TBP复合材料的极限氧指数(LOI)为28.1%,垂直燃烧测试(UL 94)等级达到V-0级(3 mm),相比于PC/ABS,PC/ABS/TBP的拉伸强度、弯曲强度、弯曲弹性模量和缺口冲击强度分别下降19.5%,16.6%,17.5%和56.1%,水平方向模后收缩率(PMSH)、垂直方向模后收缩率(PMSv)和熔体流动速率(MFR)提升68.9%,58.1%和196.1%;随着CMS加入量的增加,PC/ABS/TBP/CMS复合材料的阻燃性能先升高后下降,拉伸强度、弯曲强度和缺口冲击强度先上升后下降,热性能、刚性和尺寸稳定性逐渐提高;PC/ABS/TBP/5CMS的LOI为33.2%,UL 94等级达到V-0级(2 mm),相比于PC/ABS/TBP,其最大失重温度、拉伸强度、弯曲强度、弯曲弹性模量和缺口冲击强度分别提高7.5℃,11.7%,12.2%,14.1%和26.3%,PMSP,PMSH和MFR分别降低32.0%,26.5%和19.1%。 展开更多
关键词 聚碳酸酯/丙烯腈-丁二烯-苯乙烯共聚物 叔丁基化芳基磷酸酯 碳微球 阻燃性能 尺寸稳定性
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直接型卤素钙钛矿X射线探测器结构设计研究进展 被引量:1
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作者 韩继光 柴英俊 李晓明 《发光学报》 EI CAS CSCD 北大核心 2024年第1期25-43,共19页
X射线探测技术在医疗诊断、安防检测和科学研究等领域有着广泛的应用,直接型X射线探测器拥有更高的理论探测效率、空间和能量分辨率,受到了国内外的广泛关注。钙钛矿材料因其X射线衰减系数大、体电阻率高、光学带隙合适以及易大面积制... X射线探测技术在医疗诊断、安防检测和科学研究等领域有着广泛的应用,直接型X射线探测器拥有更高的理论探测效率、空间和能量分辨率,受到了国内外的广泛关注。钙钛矿材料因其X射线衰减系数大、体电阻率高、光学带隙合适以及易大面积制造等优势,成为直接型X射线探测器的理想材料。随着对探测性能的需求的不断提高,合理的器件结构设计显得尤为重要。本文从电极工程和能带工程两个方面出发,综述了有关直接型钙钛矿X射线探测器器件结构设计的最新进展。最后,我们对这些研究进展进行了总结,并对未来的发展进行了展望。我们希望这篇综述能为研究者们提供参考和启发。 展开更多
关键词 钙钛矿X射线探测器 器件结构 电极工程 能带工程 异质结
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先驱体转化法制备含异质元素碳化硅纤维的研究进展
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作者 吴爽 苟燕子 +4 位作者 王永寿 宋曲之 徐娜娜 韩成 王应德 《材料工程》 EI CAS CSCD 北大核心 2024年第3期1-11,共11页
连续SiC纤维及其复合材料以其优异的耐高温、抗氧化以及机械性能在航空航天以及核领域有着广泛的应用前景。先驱体转化法已成为制备连续SiC纤维最重要的方法。特定异质元素的引入可以有效改善SiC纤维的性能。本文结合我们团队近40年在... 连续SiC纤维及其复合材料以其优异的耐高温、抗氧化以及机械性能在航空航天以及核领域有着广泛的应用前景。先驱体转化法已成为制备连续SiC纤维最重要的方法。特定异质元素的引入可以有效改善SiC纤维的性能。本文结合我们团队近40年在先驱体转化法制备高性能SiC纤维领域的相关工作,首先综述了异质元素的引入方式,主要包括物理共混和化学改性;从提高先驱体的陶瓷产率、促进纤维烧结致密化,提高SiC纤维的耐高温性能以及拓展SiC纤维的功能化应用等方面阐述了异质元素的作用和机理;然后分别介绍了国内外含Ti、Al、Zr、Fe、B以及难熔金属(Hf、Ta、Nb)等含异质元素SiC纤维的组成、结构与性能以及发展现状,最后对陶瓷先驱体体系构建、异质元素种类含量与纤维性能构效关系研究、以及纤维工程化应用等研究方向进行了展望。 展开更多
关键词 先驱体转化法 碳化硅纤维 异质元素 作用机理
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