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Enabling heterogeneous catalysis to achieve carbon neutrality: Directional catalytic conversion of CO_(2) into carboxylic acids 被引量:7
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作者 Xiaofei Zhang Wenhuan Huang +4 位作者 Le Yu Max García-Melchor Dingsheng Wang Linjie Zhi Huabin Zhang 《Carbon Energy》 SCIE EI CAS CSCD 2024年第3期1-35,共35页
The increase in anthropogenic carbon dioxide(CO_(2))emissions has exacerbated the deterioration of the global environment,which should be controlled to achieve carbon neutrality.Central to the core goal of achieving c... The increase in anthropogenic carbon dioxide(CO_(2))emissions has exacerbated the deterioration of the global environment,which should be controlled to achieve carbon neutrality.Central to the core goal of achieving carbon neutrality is the utilization of CO_(2) under economic and sustainable conditions.Recently,the strong need for carbon neutrality has led to a proliferation of studies on the direct conversion of CO_(2) into carboxylic acids,which can effectively alleviate CO_(2) emissions and create high-value chemicals.The purpose of this review is to present the application prospects of carboxylic acids and the basic principles of CO_(2) conversion into carboxylic acids through photo-,electric-,and thermal catalysis.Special attention is focused on the regulation strategy of the activity of abundant catalysts at the molecular level,inspiring the preparation of high-performance catalysts.In addition,theoretical calculations,advanced technologies,and numerous typical examples are introduced to elaborate on the corresponding process and influencing factors of catalytic activity.Finally,challenges and prospects are provided for the future development of this field.It is hoped that this review will contribute to a deeper understanding of the conversion of CO_(2) into carboxylic acids and inspire more innovative breakthroughs. 展开更多
关键词 carbon neutrality carboxylic acids CO_(2)conversion heterogeneous catalyst in situ technology
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Molecularly imprinted sensor based on carboxylated carbon nanotubes/Keggin-type polyoxometalates nanocomposite for the detection of furazolidone
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作者 Yu-Lan Huang Bing Zhang +3 位作者 Yu-Lian Li Li Wang Le Dong Jian Li 《Tungsten》 EI CSCD 2024年第2期394-409,共16页
Due to its properties of mutagenic,teratogenic,and carcinogenic,the detection of furazolidone(FZD)in aquaculture is of great importance for food safety and human health.In this study,molecularly imprinted fi lms modif... Due to its properties of mutagenic,teratogenic,and carcinogenic,the detection of furazolidone(FZD)in aquaculture is of great importance for food safety and human health.In this study,molecularly imprinted fi lms modifi ed with carboxylated multi-walled carbon nanotube-phosphomolybdic acid composite were used to fabricate an electrochemical sensor for the determination of FZD.The nanocomposites were characterized using infrared spectroscopy,scanning electron microscopy,energy-dispersive X-ray spectroscopy,and X-ray diff raction.The electrochemical characteristics of the modifi ed electrodes were examined using electrochemical impedance spectroscopy,cyclic voltammetry,and diff erential pulse voltammetry.The sensor exhibited exceptional catalytic performance.The calibration curves were acquired in the concentration range of 6 nmol·L^(−1)to 0.6μmol·L^(−1),with a limit of detection of 3.38 nmol·L^(−1).Additionally,the sensor proved successful in recognizing FZD in shrimp samples with satisfactory recoveries and precision.The method provides a strategy to construct a molecularly imprinted electrochemical sensing platform using nanomaterials,which has great promise in the field of food safety. 展开更多
关键词 PHOSPHOMOLYBDATE FURAZOLIDONE POLYOXOMETALATES carboxylated multi-walled carbon nanotube Molecularly imprinted polymers Electrochemical sensor
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Sulfonated carbon catalyzed oxidation of aldehydes to carboxylic acids by hydrogen peroxide 被引量:4
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作者 Lipeng Zhou Beibei Dong +5 位作者 Si Tang Hong Ma Chen Chen Jie Xu Xiaomei Yang Jie Xu 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2013年第4期659-664,共6页
Sulfonated carbon as a strong and stable solid acid catalyst exhibited excellent catalytic performance in various acid-catalyzed reactions. Here, sulfonated carbon, as catalyst for oxidation reaction, was prepared via... Sulfonated carbon as a strong and stable solid acid catalyst exhibited excellent catalytic performance in various acid-catalyzed reactions. Here, sulfonated carbon, as catalyst for oxidation reaction, was prepared via the carbonization of starch followed by sulfonation with concentrated sulfuric acid. N2 physisorption, X-ray diffraction, Fourier transform infrared spectroscopy, X-ray fluorescence and acid-base titration were used to characterize the obtained materials. The catalytic activity of sulfonated carbon was studied in the oxidation of aldehydes to carboxylic acids using 30 wt% H2O2 as oxidant. This oxidation protocol works well for various aldehydes including aromatic and aliphatic aldehydes. The sulfonated carbon can be recycled for three times without obvious loss of activity. 展开更多
关键词 ALDEHYDE carboxylic acid oxidation hydrogen peroxide sulfonated carbon
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Ultrasensitive electrochemical determination of metronidazole based on polydopamine/carboxylic multi-walled carbon nanotubes nanocomposites modified GCE 被引量:3
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作者 Satar Tursynbolat Yrysgul Bakytkarim +1 位作者 Jianzhi Huang Lishi Wang 《Journal of Pharmaceutical Analysis》 SCIE CAS CSCD 2018年第2期124-130,共7页
An ultrasensitive electrochemical sensor based on polydopamine/carboxylic multi-walled carbon nanotubes(MWCNTs à COOH) nanocomposites modified glassy carbon electrode(GCE) was presented in this work, which has be... An ultrasensitive electrochemical sensor based on polydopamine/carboxylic multi-walled carbon nanotubes(MWCNTs à COOH) nanocomposites modified glassy carbon electrode(GCE) was presented in this work, which has been developed for highly selective and highly sensitive determination of an antimicrobial drug, metronidazole. The preparation of polydopamine/MWCNTs–COOH nanocomposites/GCE sensor is simple and possesses high reproducible, where polydopamine can be coated on the surface of MWCNTs–COOH via a simple electropolymerization process. Under optimized conditions, the proposed sensor showed ultrasensitive determination for metronidazole with a wide linear detection range from5 to 5000 mmol/dm^3 and a low detection limit of 0.25 mmol/dm^3(S/N=3). Moreover, the proposed sensor has been successfully applied for the quantitative determination of metronidazole in real drug samples. This work may provide a novel and effective analytical platform for determination of metronidazole in application of real pharmaceutical and biological samples analysis. 展开更多
关键词 METRONIDAZOLE POLYDOPAMINE carboxylic multi-walled carbon NANOTUBES NANOCOMPOSITES ELECTROCHEMICAL determination ELECTROCHEMICAL sensor
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Efficient Fixation of Carbon Dioxide by Electrolysis——Facile Synthesis of Useful Carboxylic Acids 被引量:3
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作者 Masao Tokuda 《Journal of Natural Gas Chemistry》 CAS CSCD 2006年第4期275-281,共7页
Electrochemical fixation of atmospheric pressure of carbon dioxide to organic compounds is a useful and attractive method for synthesizing of various carboxylic acids. Electrochemical fixation of carbon dioxide, elect... Electrochemical fixation of atmospheric pressure of carbon dioxide to organic compounds is a useful and attractive method for synthesizing of various carboxylic acids. Electrochemical fixation of carbon dioxide, electrochemical carboxylation, organic halides, organic triflates, alkenes, aromatic compounds, and carbonyl compounds can readily occur in the presence of an atmospheric pressure of carbon dioxide to form the corresponding carboxylic acids with high yields, when a sacrificial anode such as magnesium or aluminum is used in the electrolysis. The electrochemical carboxylation of vinyl bromides was successfully applied for the synthesis of the precursor of nonsteroidal anti-inflammatory agents such as ibuprofen and naproxen. On the other hand, supercritical carbon dioxide (scCO2) has significant potential as an environmentally benign solvent in organic synthesis and it could be used both as a solvent and as a reagent in these electrochemical carboxylations by using a small amount of cosolvent. 展开更多
关键词 carbon dioxide FIXATION supercritical carbon dioxide ELECTROLYSIS sacrificial anode carboxylic acid
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ELECTROANALYTICAL APPLICATIONS OF CARBOXYL-MODIFIED CARBON NANOTUBE FILM ELECTRODES 被引量:2
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作者 C.G.Hu W.L.Wang +1 位作者 K.J.Liao W.Zhu 《Acta Metallurgica Sinica(English Letters)》 SCIE EI CAS CSCD 2003年第4期289-294,共6页
The electrochemical behavior of a carboxyl-modified carbon nanotube films was investigated to explore its possibility in electroanalytical applicaton. Cyclic voltammetry of quinone was conducted in 1mol/L Na2SO4, whic... The electrochemical behavior of a carboxyl-modified carbon nanotube films was investigated to explore its possibility in electroanalytical applicaton. Cyclic voltammetry of quinone was conducted in 1mol/L Na2SO4, which showed a stable, quasi-reversible voltammetric response for quinone / hydroquinone, and the anodic and the cathodic peak potentials were 0.657V and -0.029V (vs. SCE) at a scan rate of 0.1V.s-1, respectively. Both anodic and cathodic peak currents depended linearly on the square root of the scan rate over the range of 0.01-0.5V.s-1, which suggested that the process of the electrode reactions was diffusion-controlled. Carboxyl-modified carbon nanotube electrodes made it possible to determine low level of dopamine selectively in the presence of a large excess of ascorbic acid in acidic media using derivative voltammetry. The results obtained were discussed in details. This work demonstrates the potential of carboxyl-modified carbon nanotube electrodes for electroanalytical applications. 展开更多
关键词 carbon nanotube ELECTROCHEMISTRY carboxyl modification DOPAMINE
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Silver-catalyzed carboxylative cyclization of alkynic hydrazones with carbon dioxide
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作者 Wenzhen Zhang Yuqian Sun +2 位作者 Min Zhang Hui Zhou Xiaobing Lu 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2019年第8期1153-1159,共7页
The development of new catalytic methodologies to synthesize heterocyclic fine chemicals using carbon dioxide as a synthon has attracted considerable attention. Herein, we report the silver( I)-catalyzed carboxylative... The development of new catalytic methodologies to synthesize heterocyclic fine chemicals using carbon dioxide as a synthon has attracted considerable attention. Herein, we report the silver( I)-catalyzed carboxylative cyclization of a variety of alkynic hydrazones with carbon dioxide to produce the corresponding 1,3,4-oxadiazin-2-ones under mild reaction conditions. In this reaction, silver(I) salts play a π-Lewis acid role for the highly efficient activation of the alkyne moiety in the hydrazone substrates. Single-crystal X-ray analysis and NOE experiments confirm that the newly formed oxadiazinone products exhibit Z configuration. Based on control experiments and NMR studies, a mechanism including the formation of a reactive carbazate intermediate, electrophilic cyclization, and subsequent protonation is proposed. This study offers an efficient and atom- economical method for the synthesis of biologically important 1,3,4-oxadiazin-2-ones. 展开更多
关键词 carbon dioxide Silver catalysis carboxylative cyclization Alkynic hydrazine Oxadiazinone Homogeneous catalysis
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Electrocarboxylation of CO_(2) with Organic Substrates:Toward Cathodic Reaction
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作者 He Yao Mei-Yan Wang +6 位作者 Chengguang Yue Bangman Feng Wenhao Ji Chunbo Qian Shengping Wang Sheng Zhang Xinbin Ma 《Transactions of Tianjin University》 EI CAS 2023年第4期254-274,共21页
Electrocarboxylation of carbon dioxide(CO_(2))using organic substrates has emerged as a promising method for the sustainable synthesis of value-added carboxylic acids due to its renewable energy source and mild reacti... Electrocarboxylation of carbon dioxide(CO_(2))using organic substrates has emerged as a promising method for the sustainable synthesis of value-added carboxylic acids due to its renewable energy source and mild reaction conditions.The reactivity and product selectivity of electrocarboxylation are highly dependent on the cathodic behavior,involving a sequence of electron transfers and chemical reactions.Hence,it is necessary to understand the cathodic reaction mechanisms for optimizing reaction performance and product distribution.In this work,a review of recent advancements in the electrocarboxylation of CO_(2)with organic substrates based on different cathodic reaction pathways is presented to provide a reference for the development of novel methodologies of CO_(2)electrocarboxylation.Herein,cathodic reactions are particularly classified into two categories based on the initial electron carriers(i.e.,CO_(2)radical anion and substrate radical anion).Furthermore,three cathodic pathways(ENE(N),ENED,and EDEN)of substrate radical anion-induced electrocarboxylation are discussed,which differ in their electron transfer sequence,substrate dissociation,and nucleophilic reaction,to highlight their implications on reactivity and product selectivity. 展开更多
关键词 carbon dioxide ELECTROCATALYSIS carboxylATION Cathodic reaction carboxylic acids
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羧基化多壁碳纳米管修饰电极测定左氧氟沙星 被引量:1
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作者 王莹 马冬云 +4 位作者 沈景辉 景文慧 赵丽曼 袁寰 李炳寅 《吉首大学学报(自然科学版)》 CAS 2024年第4期76-81,共6页
探究了左氧氟沙星在羧基化多壁碳纳米管(c-MWCNTs)修饰电极上的电化学行为,并采用循环伏安法对左氧氟沙星含量进行了测定.结果表明,c-MWCNTs修饰电极对左氧氟沙星有明显的电催化作用;在pH值为5.0的NaH_(2)PO_(4)Na_(2)HPO_(4)缓冲溶液中... 探究了左氧氟沙星在羧基化多壁碳纳米管(c-MWCNTs)修饰电极上的电化学行为,并采用循环伏安法对左氧氟沙星含量进行了测定.结果表明,c-MWCNTs修饰电极对左氧氟沙星有明显的电催化作用;在pH值为5.0的NaH_(2)PO_(4)Na_(2)HPO_(4)缓冲溶液中,左氧氟沙星溶液的氧化峰电流与浓度在1×10^(-5)~4×10^(-4)mol/L范围内呈良好线性关系,相关系数为0.998,检出限为2.87×10^(-6)mol/L;在最优测试条件下,左氧氟沙星片剂的加标回收率为98.7%~103.0%,相对标准偏差为1.31%~3.99%(n=5);羧基化多壁碳纳米管修饰玻碳电极(c-MWCNTs/GCE)对左氧氟沙星有较好的电化学响应,灵敏度高,可用于药品中左氧氟沙星测定. 展开更多
关键词 左氧氟沙星 电化学分析 羧基化碳纳米管 玻碳电极
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小麦叶片和冠层尺度气体交换模型关键参数的季节变化特征
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作者 赵福年 刘江 +4 位作者 张强 张良 王润元 王鹤龄 侯金亮 《气象科学》 2024年第1期166-175,共10页
本文从叶片和冠层尺度入手,采用手持式光合仪和涡动相关法,分析确定C3作物春小麦和冬小麦气体交换模型关键参数随季节变化的特征。结果表明:春小麦叶片尺度最大羧化速率和最大电子传递速率在生育末期快速减小,其他阶段差异不显著,但二... 本文从叶片和冠层尺度入手,采用手持式光合仪和涡动相关法,分析确定C3作物春小麦和冬小麦气体交换模型关键参数随季节变化的特征。结果表明:春小麦叶片尺度最大羧化速率和最大电子传递速率在生育末期快速减小,其他阶段差异不显著,但二者之比随发育期变化相对稳定,均值为2.2;春小麦生长季叶片气孔导度模型斜率在9~11间变动,均值为9.7。冬小麦冠层尺度最大羧化速率和最大电子传递速率随发育期呈抛物线变化,但二者之比相对稳定,均值为1.43;冬小麦冠层导度模型斜率在不同年份不同季节变化无明显规律,整个生育期围绕均值12波动。本研究论证了表征作物光合能力的参数随生育期变化以及气孔导度模型斜率相对稳定的特征。可为陆气相互作用过程分析以及生态系统碳—水循环模拟提供参数化依据。 展开更多
关键词 最大羧化速率 气孔导度模型斜率 小麦 碳—水交换 光合能力
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氧化铜/羧基化碳纳米片修饰玻碳电极用于尿酸的灵敏检测
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作者 利健文 黄象金 韦寿莲 《化学研究与应用》 CAS 北大核心 2024年第7期1451-1457,共7页
制备了氧化铜(CuO)纳米棒和羧基化碳纳米片(cCNSs)两种材料,并通过滴涂方式将其修饰在玻碳电极(GCE)表面,构建了一种用于检测尿酸(UA)的电化学传感器。采用扫描电镜(SEM)、X-射线衍射(XRD)和X射线光电子能谱(XPS)对所制备的材料进行表... 制备了氧化铜(CuO)纳米棒和羧基化碳纳米片(cCNSs)两种材料,并通过滴涂方式将其修饰在玻碳电极(GCE)表面,构建了一种用于检测尿酸(UA)的电化学传感器。采用扫描电镜(SEM)、X-射线衍射(XRD)和X射线光电子能谱(XPS)对所制备的材料进行表征。通过微分脉冲伏安法(DPV)和循环伏安法(CV)研究了传感器的电化学性能。结果表明,CuO/cCNSs修饰电极对UA的氧化有很好的催化效果。与GCE电极相比,UA在CuO/cCNSs修饰电极上的峰电流增强了约122倍。在0.3~-30.0μmol·L^(-1)浓度范围内,UA的氧化峰电流与其浓度呈良好的线性关系,检出限为0.087μmol·L^(-1)。该传感器具有良好的选择性、重现性和稳定性,应用于人体尿样中UA的检测,加标回收率为83.2%~103%。 展开更多
关键词 尿酸 电化学传感器 羧基化碳纳米片 氧化铜
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基于CMWCNT/Nafion的增强型离子聚合物金属复合材料的制备及致动性能 被引量:1
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作者 李帆 李廷鱼 +2 位作者 李朋伟 李银辉 郭丽芳 《微纳电子技术》 CAS 2024年第3期59-67,共9页
离子聚合物金属复合材料(IPMC)是一种新型的电活性材料,具有体积小、质量轻、驱动电压低等优点,但驱动力小、稳定工作时间短等问题限制着其柔性致动性能。提出了一种基于银基IPMC的增强型致动器,通过在IPMC的基底聚合物中掺杂羧基化多... 离子聚合物金属复合材料(IPMC)是一种新型的电活性材料,具有体积小、质量轻、驱动电压低等优点,但驱动力小、稳定工作时间短等问题限制着其柔性致动性能。提出了一种基于银基IPMC的增强型致动器,通过在IPMC的基底聚合物中掺杂羧基化多壁碳纳米管(CMWCNT),来提高IPMC的整体机械性能和致动性能。其中,掺杂质量分数0.5%CMWCNT的IPMC的最大尖端位移和驱动力分别增加至未优化银基IPMC的1.60倍与2.32倍,该性能的提升归因于CMWCNT良好的导电性和羧基对水合阳离子迁移的加速作用。与未优化的银基IPMC相比,掺杂质量分数0.5%CMWCNT时IPMC驱动速率可提升至3.57倍。研究结果可为IPMC在各领域的应用发展提供参考。 展开更多
关键词 离子聚合物金属复合材料(IPMC) 增强型致动器 羧基化多壁碳纳米管(CMWCNT) 柔性致动性能 电活性材料
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碳纳米管羧基功能化及其对水泥石的影响
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作者 贾慧 金鑫 +1 位作者 魏浩光 李小江 《钻井液与完井液》 CAS 北大核心 2024年第5期640-645,共6页
随着非常规油气井开发的不断深入,复杂的地下环境对水泥石的各项力学性能指标提出更高的要求,因此,急需开发高性能的纳米材料用于改造水泥石性能。采用稀酸酸化工艺制备羧基功能化碳纳米管分散液,通过接触角、紫外-可见吸收光谱和沉降... 随着非常规油气井开发的不断深入,复杂的地下环境对水泥石的各项力学性能指标提出更高的要求,因此,急需开发高性能的纳米材料用于改造水泥石性能。采用稀酸酸化工艺制备羧基功能化碳纳米管分散液,通过接触角、紫外-可见吸收光谱和沉降稳定性等测试对分散液的分散能力进行讨论,并对羧基功能化碳纳米管提高水泥石力学性能的效果进行了验证。研究结果表明,羧基功能化可使碳纳米管的粒径减小89.71%,并使疏水材料转变为亲水材料,同时,羧基功能化碳纳米管在水中的分散稳定性提升100%;0.005%加量的羧基功能化碳纳米管使水泥石的抗压强度提高16.05%,抗折强度提高25.82%,抗拉强度提高18.07%。 展开更多
关键词 碳纳米管 羧基 水泥石
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短碳链二元羧酸与磷酸二铵复合提高磷在土壤中的扩散距离和有效性
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作者 孔维众 张水勤 +5 位作者 李燕婷 徐久凯 许猛 高强 赵秉强 袁亮 《植物营养与肥料学报》 CAS CSCD 北大核心 2024年第6期1163-1172,共10页
【目的】有机酸与磷肥结合施用可有效减少土壤中磷固定,但有机酸碳链长度与磷肥有效性的关系尚不明确。将不同碳链长度的二元羧酸与磷酸二铵复合,研究其对磷酸二铵在土壤中的扩散及有效性的影响,以期为高效磷肥产品开发提供理论依据。... 【目的】有机酸与磷肥结合施用可有效减少土壤中磷固定,但有机酸碳链长度与磷肥有效性的关系尚不明确。将不同碳链长度的二元羧酸与磷酸二铵复合,研究其对磷酸二铵在土壤中的扩散及有效性的影响,以期为高效磷肥产品开发提供理论依据。【方法】试验以草酸(OA)、丁二酸(BA)、己二酸(AA)、辛二酸(SA)为供试材料,分别按0.5%的质量比与粉状磷酸二铵混合均匀后挤压造粒,得到4个含有不同碳链长度的二元羧酸与磷酸二铵复合磷肥试验样品(代号分别为OAP、BAP、AAP、SAP),磷酸二铵样品(DAP)也按照同样方法挤压造粒。磷培养试验以5个肥料样品为处理,以不添加磷肥为对照(CK),每个处理设置18个重复。在培养的第1、3、7、14和28天,进行滤纸可视化显色,测定肥料磷的扩散距离(半径),同时采集土样测定速效磷、Ca2-P和Ca8-P含量,测定pH及碱性磷酸酶活性。【结果】与DAP相比,OAP、BAP、AAP、SAP处理均增加了磷素扩散距离,扩散距离各处理的排序为OAP>BAP>AAP>SAP,OAP处理的磷扩散距离较DAP平均增加了29.5%。培养28天时,4个二元羧酸磷酸二铵复合磷肥处理的土壤平均速效磷、Ca2-P、Ca8-P含量分别较DAP提高了0.48%~12.6%、4.06%~37.1%、1.25%~20.9%,均以OAP的提高幅度最高。在培养3~28天,二元羧酸磷酸二铵复合磷肥处理的土壤碱性磷酸酶活性均高于DAP,以OAP处理的活性最高。与CK处理相比,施磷肥处理土壤pH显著下降,以OAP处理降幅最大。【结论】供试二元羧酸与磷酸二铵复合均可减少磷的固定,提高土壤速效磷含量,增加磷肥在土壤中的扩散距离;其中,以草酸磷酸二铵复合肥效果最好。 展开更多
关键词 二元羧酸 碳链长度 羧基含量 磷扩散 速效磷含量 磷形态
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可见光催化CO_(2)参与的芳基烯烃碳碳双键断键羧基化反应
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作者 曹可弓 高田宇 +7 位作者 廖黎丽 冉川昆 蒋元旭 章炜 周琦 叶剑衡 蓝宇 余达刚 《Chinese Journal of Catalysis》 SCIE CAS CSCD 2024年第1期74-80,共7页
烯烃广泛存在于自然界中,在医药、农药和材料等领域具有重要应用.烯烃的C=C键断裂和转化是许多工业过程的基础,可以实现烃类资源的重组与利用.目前,C=C键参与的氧化裂解和烯烃复分解反应已有广泛的研究.相比而言,C=C键参与的还原裂解虽... 烯烃广泛存在于自然界中,在医药、农药和材料等领域具有重要应用.烯烃的C=C键断裂和转化是许多工业过程的基础,可以实现烃类资源的重组与利用.目前,C=C键参与的氧化裂解和烯烃复分解反应已有广泛的研究.相比而言,C=C键参与的还原裂解虽然是烯烃与一系列亲电试剂反应合成功能分子的重要途径,但受限于烯烃自身结构和反应特点,该过程存在较大的挑战,目前研究很少.CO_(2)具有储量丰富、廉价易得、无毒且可循环再生等优点,是合成多种大宗化学品及精细化学品的理想碳一资源.然而,CO_(2)由于热力学稳定性及动力学惰性,在温和条件下难以高效、高选择性转化.因此,利用CO_(2)参与烯烃C=C键还原裂解,选择性构建高值化合物,是一个重要且具有挑战性的研究方向.近年来,可见光催化由于具有反应条件温和、官能团兼容性高等优点,为有机合成等领域提供了新的发展机遇.本文利用二环己基甲基胺作为电子给体,成功实现了可见光催化CO_(2)参与的芳基烯烃C=C键断键羧基化反应.该反应成功的关键在于,二环己基甲基胺既能高效还原淬灭激发态光敏剂并参与烯烃的胺基烷基-羧基化反应,又不明显抑制胺基烷基化中间体对激发态光敏剂的还原淬灭.研究结果表明,多种不同取代(如给电子基和吸电子基)的芳基烯烃均可与CO_(2)发生羧基化反应,高效高选择性地构建了一系列官能团丰富的芳基乙酸类化合物(如萘普生等药物分子).该方法具有反应条件温和(1 atm,室温)、官能团耐受性好以及可用于合成药物衍生物等特点.此外,本文通过氘代实验等机理研究和密度泛函理论计算证明,胺甲基羧化中间体、苄基自由基和苄基碳负离子都是该反应的关键中间体,并提出了可能的反应机理:首先,二环己基甲基胺还原淬灭激发态光敏剂,产生α-胺基碳自由基,与芳基烯烃发生自由基加成反应,得到苄基自由基,进而被还原态光敏剂还原为碳负离子,对CO_(2)亲核进攻得到烯烃的胺基烷基-羧基化中间体;作为电子给体,该中间体可以淬灭另一分子的激发态光敏剂,并通过分子内去质子化过程,产生α-胺基碳自由基物种,进而经历自由基型β-C断裂,生成热力学更稳定的羧基化苄基自由基,从而实现了烯烃C=C键的还原裂解;最后,新产生的苄基自由基被进一步还原为碳负离子,经历质子化过程后得到目标产物.综上,本文以还原裂解的方式丰富了C=C键断键官能团化反应领域,在温和条件下实现了CO_(2)的高效高选择性转化,合成了高附加值的芳基乙酸类化合物,阐明了反应机制,为烯烃和CO_(2)的同时高值化利用提供了新思路,为后续相关反应的开发和应用提供参考. 展开更多
关键词 二氧化碳 可见光催化 C=C键裂解 羧基化 芳基乙酸
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抗癌药中间体2-噻吩甲酸制备新工艺研究
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作者 姜维佳 雷伟 +2 位作者 陈杰 王青 王玉高 《现代化工》 CAS CSCD 北大核心 2024年第6期175-180,共6页
在促进剂K_(2)CO_(3)/TiO_(2)的作用下,通过二氧化碳的羧基化反应成功地将噻吩转化为2-噻吩甲酸,并优化了合成条件,考察了促进剂K_(2)CO_(3)/TiO_(2)的结构、性质对合成路线的影响。结果表明,K_(2)CO_(3)/TiO_(2)起主要促进作用的为表... 在促进剂K_(2)CO_(3)/TiO_(2)的作用下,通过二氧化碳的羧基化反应成功地将噻吩转化为2-噻吩甲酸,并优化了合成条件,考察了促进剂K_(2)CO_(3)/TiO_(2)的结构、性质对合成路线的影响。结果表明,K_(2)CO_(3)/TiO_(2)起主要促进作用的为表面无定型K_(2)CO_(3);考虑到产物的热稳定性,反应温度不宜超过300℃;产物在反应刚开始的1 h内大量生成,此后生成速率急速下降。该研究不仅开发了新颖、环保和高效的2-噻吩甲酸合成路线,还拓展了二氧化碳的高效利用途径。 展开更多
关键词 2-噻吩甲酸 抗癌药中间体 二氧化碳 羧基化 合成
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光热双响应形状记忆聚己内酯的制备与性能
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作者 张勇波 童大山 汪艳 《高分子材料科学与工程》 EI CAS CSCD 北大核心 2024年第5期154-159,共6页
形状记忆聚合物(SMPs)因其形变量大、形状恢复性能优异及刺激相应方式丰富等优点在医疗器械、航天航空等多个领域有着广阔的应用前景。文中以羧基化的多壁碳纳米管(MWCNT)为光热转换填料,采用过氧化二异丙苯(DCP)热引发聚己内酯(PCL)交... 形状记忆聚合物(SMPs)因其形变量大、形状恢复性能优异及刺激相应方式丰富等优点在医疗器械、航天航空等多个领域有着广阔的应用前景。文中以羧基化的多壁碳纳米管(MWCNT)为光热转换填料,采用过氧化二异丙苯(DCP)热引发聚己内酯(PCL)交联制备了羧基化MWCNT/PCL光热双响应形状记忆材料,研究了该复合材料的光热转换性能、形状记忆性能及力学性能等。结果表明,羧基化MWCNT的加入使得材料具备了光响应的特性,同时对力学性能也有一定的提升;当DCP和羧基化MWCNT的质量分数分别为1.5%和1%时,材料的形状固定率和形状回复率最优,分别为99.37%和98.53%,且在近红外光照射下30 s内便能回复原样,表现出优秀的形状记忆性能。相较于未交联的复合材料,拉伸强度从15.37 MPa提高到27.85 MPa,提高了81.85%,而断裂伸长率从1046.5%降低至982.48%,下降了6.12%。 展开更多
关键词 形状记忆聚合物 聚己内酯 羧基化多壁碳纳米管 光热响应
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CNT-COOH含量对PUR基复合材料性能影响的分子动力学模拟
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作者 王梓霖 闫新亮 +3 位作者 黄肖勇 李雅琴 高如月 付一政 《工程塑料应用》 CAS CSCD 北大核心 2024年第4期61-68,共8页
为分析功能化碳纳米管含量对聚合物基复合体系性能的影响,通过分子动力学模拟方法,建立了不同含量的聚氨酯/羧基化碳纳米管(PUR/CNT-COOH)复合体系模型,比较了不同复合体系的拉伸强度、拉伸弹性模量(E)、剪切模量(B)以及体积模量(G)等... 为分析功能化碳纳米管含量对聚合物基复合体系性能的影响,通过分子动力学模拟方法,建立了不同含量的聚氨酯/羧基化碳纳米管(PUR/CNT-COOH)复合体系模型,比较了不同复合体系的拉伸强度、拉伸弹性模量(E)、剪切模量(B)以及体积模量(G)等性能。通过分析PUR/CNT-COOH复合体系的径向分布函数、氢键作用、氢键密度以及不同种类的氢键数量等性能,从微观层面探究了CNT-COOH含量对复合体系性能的影响规律。模拟结果表明,随着CNT-COOH含量逐渐增加,PUR/CNT-COOH复合体系的屈服强度逐渐增大,拉伸性能逐渐下降;PUR/CNT-COOH复合体系的E,G以及B均随CNT-COOH含量的增加而升高。CNT-COOH在复合体系中的占比越大,CNT-COOH与PUR基体间的相互作用越强;PUR基体间的相互作用力下降,复合体系的拉伸性能下降;随CNT-COOH含量的增加,二者相互作用增强,使其更易发生团聚现象。径向分布函数分析结果表明,随着CNT-COOH含量的增加,填料与基体间的相互作用逐渐增强,基体自身的相互作用明显减弱。氢键分析结果表明,随着CNT-COOH的增加,填料间的氢键数目不断升高,基体间的氢键数目不断下降。 展开更多
关键词 分子动力学模拟 羧基化碳纳米管 聚氨酯 径向分布函数 界面相互作用 氢键
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Visible-Light Photoredox-Catalyzed Carbon/Carboxylation of Alkenes with Malonates and CO_(2)
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作者 Zhang Aolong Yang Han +2 位作者 Cheng Peidong Yao Yang Sun Song 《有机化学》 SCIE CAS CSCD 北大核心 2024年第10期3159-3168,共10页
A photoredox-catalyzed cascade carbon/carboxylation of activated alkenes with malonates acetals and CO_(2) has been achieved,leading to a range of functionalized 1,1,3-tricarboxylates in good efficiency under mild rea... A photoredox-catalyzed cascade carbon/carboxylation of activated alkenes with malonates acetals and CO_(2) has been achieved,leading to a range of functionalized 1,1,3-tricarboxylates in good efficiency under mild reaction conditions.This reaction provides a facile and sustainable method for the synthesis of tricarboxylates by using CO_(2) as the carboxylic source. 展开更多
关键词 carbon dioxide carboxylATION alkene difunctionalization visible-light catalyzed
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Advances in Dearomative Carboxylation of Aromatic Compounds with Carbon Dioxide
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作者 Li Jiayuan Yi Yaping Xi Chanjuan 《有机化学》 SCIE CAS CSCD 北大核心 2024年第10期3136-3146,共11页
Dearomative carboxylation of aromatic compounds with carbon dioxide(CO_(2))could be utilized for the synthesis of cyclic carboxylative frameworks.The dearomative carboxylation exhibits advantages such as reconstitutio... Dearomative carboxylation of aromatic compounds with carbon dioxide(CO_(2))could be utilized for the synthesis of cyclic carboxylative frameworks.The dearomative carboxylation exhibits advantages such as reconstitution molecular spatial structure,environmental friendliness,mild conditions,high yield,and high selectivity,and is of significant importance in pharmaceutical synthesis and natural product chemistry.The recent advancements in the dearomative carboxylation of aromatics with CO_(2) are summarized,including elucidation of the reaction characteristics and the scope of substrates via transition-metal catalysis,photoredox catalysis,and electropromoted chemistry. 展开更多
关键词 dearomative carboxylation aromatic compound carbon dioxide metal catalysis PHOTOCATALYSIS electropromoted chemistry
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