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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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Carboxylic bacterial cellulose fiber-based hydrogel electrolyte with imidazole-type ionic liquid for dendrite-free zinc metal batteries
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作者 Tianyun Zhang Xiaohong Shi +4 位作者 Yu Li Sambasivam Sangaraju Fujuan Wang Liang Yang Fen Ran 《Materials Reports(Energy)》 EI 2024年第2期45-53,共9页
Aqueous zinc metal batteries are regarded as the most promising energy storage system due to their advantages of high safety,low cost,and high theoretical capacity.However,the growth of dendrites and the occurrence of... Aqueous zinc metal batteries are regarded as the most promising energy storage system due to their advantages of high safety,low cost,and high theoretical capacity.However,the growth of dendrites and the occurrence of side reactions hinder the development of zinc metal batteries.Despite previous attempts to design advanced hydrogel electrolytes,achieving high mechanical performance and ionic conductivity of hydrogel electrolytes has remained challenging.In this work,a hydrogel electrolyte with an ionic crosslinked network is prepared by carboxylic bacterial cellulose fiber and imidazole-type ionic liquid,following by a covalent network of polyacrylamide.The hydrogel electrolyte possesses a superior ionic conductivity of 43.76 mS cm^(−1),leading to a Zn^(2+)migration number of 0.45,and high mechanical performance with an elastic modulus of 3.48 GPa and an elongation at breaking of 38.36%.More importantly,under the anion-coordination effect of the carboxyl group in bacterial cellulose and[BF4]−in imidazole-type ionic liquid,the solvation sheath of hydrated Zn^(2+)ions and the nucleation overpotential of Zn plating are regulated.The results of cycled testing show that the growth of zinc dendrites is effectively inhibited and the generation of irreversible by-products is reduced.With the carboxylic bacterial cellulose-based hydrogel electrolyte,the Zn||Zn symmetric batteries offer good cyclability as well as Zn||Ti batteries. 展开更多
关键词 Bacterial cellulose fiber Ionic liquids carboxylic group Gel electrolyte Zn metal batteries
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Effect of linear carboxylic ester on low temperature performance of LiMn_2O_4-graphite cells 被引量:3
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作者 洪树 李劼 +2 位作者 王冠超 张治安 赖延清 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2015年第1期206-210,共5页
To improve the low-temperature performances of Li-ion cells, three types of linear carboxylic ester-based electrolyte, such as EC/EMC/EA(1:1:2, mass ratio), EC/EMC/EP(1:1:2, mass ratio) and EC/EMC/EB(1:1:2,... To improve the low-temperature performances of Li-ion cells, three types of linear carboxylic ester-based electrolyte, such as EC/EMC/EA(1:1:2, mass ratio), EC/EMC/EP(1:1:2, mass ratio) and EC/EMC/EB(1:1:2, mass ratio), were prepared to substitute for industrial electrolyte(EC/EMC/DMC). Then, 18650-type Li Mn2O4-graphite cells(nominal capacity of 1150 mA ·h) were assembled and studied. Results show that the cells containing three types of electrolyte are able to undertake 5C discharging current with above 93% capacity retention at-20 °C. Electrochemical impedance spectra show that the discharge capacity fading of Li-ion cells at low temperature is mainly ascribed to the charge transfer resistance increasing with temperature decreasing. In comparison, the cells containing electrolyte of 1.0 mol/L LiPF6 in EC/EMC/EA(1:1:2, mass ratio) have the highest capacity retention of 90% at-40 °C and 44.41% at-60 °C, due to its lowest charge-transfer resistance. 展开更多
关键词 Li-ion cells low temperature performance ELECTROLYTE linear carboxylic ester ionic conductivity charge-transfer resistance
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Two New Phenolic Carboxylic Acid Esters from Opuntia vulgaris
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作者 蒋建勤 叶文才 +2 位作者 陈真 楼凤昌 闵知大 《Journal of Chinese Pharmaceutical Sciences》 CAS 2002年第1期1-3,共3页
Two new phenolic carboxylic acid esters n-butyl eucomate(1) and methyl eucomate (2) and six known compounds eucomic acid(3), 3-β-acetyl-taraxerol (4), friedelin(5),lupenone(6),methyl linoleate(7) and methy... Two new phenolic carboxylic acid esters n-butyl eucomate(1) and methyl eucomate (2) and six known compounds eucomic acid(3), 3-β-acetyl-taraxerol (4), friedelin(5),lupenone(6),methyl linoleate(7) and methyl oleate(8) were isolated from the stems of Opuntia vulgaris Mill(Cactaceae). Their structures were determined on the basis of spectral methods. Compounds 3,4,6,7,8 were isolated for the first time from this plant. 展开更多
关键词 Opuntia vulgaris Phenolic carboxylic acid ester n-Butyl eucomate Methyl eucomate
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Sensitive Voltammetric Determination of Captopril Using a Carbon Paste Electrode Modified with Nano-TiO_2/Ferrocene Carboxylic Acid 被引量:6
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作者 Jahan Bakhsh RAOOF Reza OJANI Mehdi BAGHAYERI 《催化学报》 SCIE EI CAS CSCD 北大核心 2011年第11期1685-1692,共8页
A carbon paste electrode (CPE) modified with ferrocene carboxylic acid (FcCA) and TiO2 nanoparticles was constructed by incorporating TiO2 nanoparticles and ferrocene carboxylic acid into the carbon paste matrix. The ... A carbon paste electrode (CPE) modified with ferrocene carboxylic acid (FcCA) and TiO2 nanoparticles was constructed by incorporating TiO2 nanoparticles and ferrocene carboxylic acid into the carbon paste matrix. The electrochemical behavior of captopril (CAP) at the surface of the modified electrode was investigated using electroanalytical methods. The modified electrode showed excellent electrocatalytic activity for the oxidation of CAP in aqueous solutions at physiological pH values. Cyclic voltammetric curves showed that the oxidation of CAP at the surface of the modified electrode reduced its overpotential by more than 290 mV. The modified electrode was used for detecting captopril using cyclic voltammetry and square wave voltammetry techniques. A calibration curve in the range of 0.03 to 2400 μmol/L was obtained that had a detection limit of 0.0096 μmol/L (3?) under the optimized conditions. The modified electrode was successfully used for the determination of captopril in pharmaceutical and biological samples. 展开更多
关键词 ELECTROCATALYSIS modified electrode NANO-TIO2 ferrocene carboxylic acid captopril cyclic voltammetry
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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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Comparison of Carboxylic Acids in Some Crude Oils and Their Diesel Distillates and VGOs:Characterized by Negative-Ion Electrospray Ionization Fourier Transform Ion Cyclotron Resonance Mass Spectrometry (Negative-Ion ESI FT-ICR MS) 被引量:3
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作者 Wang Zhenhua Tu Yongshan 《China Petroleum Processing & Petrochemical Technology》 SCIE CAS 2011年第3期8-15,共8页
Three high-acidity crudes, Dar, SZ36-1, and QHD326, were separated through distillation into several fractions, including diesel distillates, and VGOs. Samples were characterized by negative-ion ESI FT-ICR MS. The O2 ... Three high-acidity crudes, Dar, SZ36-1, and QHD326, were separated through distillation into several fractions, including diesel distillates, and VGOs. Samples were characterized by negative-ion ESI FT-ICR MS. The O2 class species (petroleum carboxylic acids), which have a close relationship with corrosion of equipment caused by high-acidity crudes, were put in the focus of attention and were discussed in this paper. Monocyclic, bicyclic, and tricyclic naphthenic acids are the main types of petroleum carboxylic acids in naphthenic-base crudes (SZ36-1 and QHD326). But the main types of petroleum carboxylic acids in paraffinic-base crude (Dar) are aliphatic acids and monocyclic naphthenic acids. The O2 class species in SZ36-1 and QHD326 are distributed in a wider range and have bigger DBE value (double-bond equivalence value) and carbon number than Dar. Bicyclic naphthenic acids have the highest proportion among petroleum carboxylie acids in diesel distillates, but monocyclic and tricyclic naphthenic acids also occupy a high proportion. Particularly, aliphatic acids in the diesel distillate of Dar still have high proportion among petroleum carboxylic acids. The distribution of petroleum carboxylic acids in VGO is basically identical. The bicyclic naphthenic acids assume the first place (about 25 m%), while the monocyclic and tricyclic naphthenic acids take the next place. The comparison of petroleum carboxylic acids in diesel distillates and VGOs has revealed that the molecules of carboxylic acids in VGOs are not only bigger but also more complicated. 展开更多
关键词 O2 class species petroleum carboxylic acids aliphatic acids naphthenic acid
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Solvent Extraction of Yttrium by Task-specific Ionic Liquids Bearing Carboxylic Group 被引量:2
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作者 王威 刘郁 +3 位作者 徐爱梅 杨华玲 崔红敏 陈继 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2012年第1期40-46,共7页
A new kind of hydrophobic ionic liquids [1-alkyl-3-(1-carboxylpropyl)im][PF6] has been synthesized, and their extraction.properties for Y(III) in the nitric acid medium was also investigated. The effects of extrac... A new kind of hydrophobic ionic liquids [1-alkyl-3-(1-carboxylpropyl)im][PF6] has been synthesized, and their extraction.properties for Y(III) in the nitric acid medium was also investigated. The effects of extractant concentration, equilibrium pH of aqueous phase, salt concentration, temperature etc. were discussed. The results show that this kind of Task-Specific Ionic Liquid (TSIL) needs to be saponified before being used for the Y(III) extraction, and the extraction is-acid dependent,-and the extraction efficiency increases with the aqueous phase acldity decreasing. Furthermore, the loaded organic phase is easy to be stripped; more than 95% Y(III) could be stripped from the loaded organic phase when the stripping acidity is higher than 0.07 mol-L-1. The slope analysis technique is used to investigate the extraction mechanism, and a possible cation-exchange extraction mechanism is proposed in the oresent extraction system. 展开更多
关键词 task-special ionic liquids extraction YTTRIUM carboxylic acidic
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Carboxylic Esterase and Its Associations With Long-term Effects of Organophosphorus Pesticides 被引量:2
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作者 ZHI-JUN ZHOU JIE ZHENG +1 位作者 QIANG-EN WU FANG XIE 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2007年第4期284-290,共7页
To examine a) the effect of organophosphorus pesticide exposure on activity of carboxylic esterases, namely butyrylcholinesterase (BChE), carboxylesterase (CarbE) and paraoxonase (PonE); and b) the association... To examine a) the effect of organophosphorus pesticide exposure on activity of carboxylic esterases, namely butyrylcholinesterase (BChE), carboxylesterase (CarbE) and paraoxonase (PonE); and b) the association of polymorphisms of BChE and PonE with individual genetic susceptibility to organophosphorus pesticide exposure. Methods A cross-sectional study was conducted in 75 workers exposed to organophosphorus pesticides and 100 non-exposed controls. The serum activity of these enzymes was measured. Variant forms of BCHE-K, PON-192, and PON-55 were detected. A symptom score was developed as a proxy measure of clinical outcomes. Results Activities of both BChE and CarbE were lower in exposed workers (27.3±21.65 runol.hl.mL^-l and 235.6±104.03 nmol-min^-l.mL^-l) than in non-exposed workers (78.313±30.354 nmol.h^-l.mL^-1 and 362.681_+194.997 nmol.min^-1.mL^-1). The activity of PonE was not associated with exposure status. The AChE activity in the exposed workers with BCHE-K genotype UU (61 cases), genotype UK (12 cases) and genotype KK (2 cases) was 105.05, 84.42 and 79.00 mmol-h^-1.mL^-1, respectively and the accumulative symptom scores were 3.74, 9.17, and 12.50 accordingly. The AChE activity in the exposed workers with PON-192 genotype BB (37), genotype AB (27) and genotype AA (11) was 116.8, 91.2, and 72,3 mmol-h^-1.mL^-1, respectively and the symptom scores were 2.00, 6.74, and 9.73 accordingly. The AChE activity in those with PON-55 genotype LL (70) and genotype LM (5) was 102.4 and 82.8 mmol-h^-1.mL^-1 and the symptom scores were 4.53 and 9.20. The symptom score was the highest in individuals with abnormal homozygote for each of the three gene loci. Condusions Long-term exposure to organophosphorus pesticides can inhibit BChE and CarbE activity, but exerts no inhibitory effect on PonE activity. Different genotypes of BCHE-K, PON-192, and PON-55 may be related to the severity of adverse health effects of organophosphorus pesticide exposure. Implications of potentially higher susceptibility of workers with mutant homozygotes should be evaluated to reduce health risks. 展开更多
关键词 carboxylic esterases Organophosphorus pesticides POLYMORPHISM SUSCEPTIBILITY
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Reductive Conversion of Biomass-Derived Furancarboxylic Acids with Retention of Carboxylic Acid Moiety 被引量:2
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作者 Yoshinao Nakagawa Mizuho Yabushita Keiichi Tomishige 《Transactions of Tianjin University》 EI CAS 2021年第3期165-179,共15页
Catalytic reduction systems of 2-furancarboxylic acid(FCA)and 2,5-furandicarboxylic acid(FDCA)with H 2 without reduction of the carboxyl groups are reviewed.FCA and FDCA are produced from furfural and 5-hydroxymethylf... Catalytic reduction systems of 2-furancarboxylic acid(FCA)and 2,5-furandicarboxylic acid(FDCA)with H 2 without reduction of the carboxyl groups are reviewed.FCA and FDCA are produced from furfural and 5-hydroxymethylfurfural which are important platform chemicals in biomass conversions.Furan ring hydrogenation to tetrahydrofuran-2-carboxylic acid(THFCA)and tetrahydrofuran-2,5-dicarboxylic acid(THFDCA)easily proceeds over Pd catalysts.Hydrogenolysis of one C–O bond in the furan ring produces 5-hydroxyvaleric acid(5-HVA)and 2-hydroxyadipic acid.2-Hydroxyvaleric acid is not produced in the reported systems.5-HVA can be produced as the lactone form(δ-valerolactone;DVL)or as the esters depending on the solvent.These reactions proceed over Pt catalysts with good yields(~70%)at optimized conditions.Hydrogenolysis of two C–O bonds in the furan ring produces valeric acid and adipic acid,the latter of which is a very important chemical in industry and its production from biomass is of high importance.Adipic acid from FDCA can be produced directly over Pt-MoO_(x) catalyst,indirectly via hydrogenation and hydrodeoxygenation as one-pot reaction using the combination of Pt and acid catalysts such as Pt/niobium oxide,or indirectly via two-step reaction composed of hydrogenation catalyzed by Pd and hydrodeoxygenation catalyzed by iodide ion in acidic conditions.Only the two-step method can give good yield of adipic acid at present. 展开更多
关键词 Biomass HYDROGENOLYSIS Furanic compound carboxylic acid
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Syntheses,Crystal Structures and Antibacterial Activities of 5-Chloro-3-methyl-1-phenyl-1H-pyrazole-4-carboxylic Acid and Its Copper(Ⅱ) Compound 被引量:2
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作者 温辉梁 康静静 +2 位作者 戴兵 邓瑞红 胡海威 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2015年第1期33-40,共8页
The title compounds 5-chloro-3-methyl-1-phenyl-1H-pyrazole-4-carboxylic acid(C11H9Cl N2O2, HL)(1) and [Cu(L)2(H2O)](2) were prepared and structurally characterized by elemental analysis, IR and single-crysta... The title compounds 5-chloro-3-methyl-1-phenyl-1H-pyrazole-4-carboxylic acid(C11H9Cl N2O2, HL)(1) and [Cu(L)2(H2O)](2) were prepared and structurally characterized by elemental analysis, IR and single-crystal X-ray diffraction. Compound 1(C11H9Cl N2O2) crystallizes in the monoclinic system, space group P21/n with a = 7.249(3), b = 20.515(10), c = 7.249(3),β= 96.30°, V = 1071.6(9) ?3, Z = 4, Mr = 236.65, Dc = 1.467 g/cm3, F(000) = 488, GOOF = 1.029, μ= 0.341 mm-1, the final R = 0.0736 and w R = 0.1966 for 1500 observed reflections with I 〉 2σ(I). Compound 2(C22H18Cl2Cu N4O5) crystallizes in the monoclinic system, space group P21/c with a = 7.2931(6), b = 24.548(2), c = 13.2726(11), β= 99.4040(10)°, V = 2344.2(3) ?3, Z = 4, Mr = 552.84, Dc = 1.566 g/cm3, F(000) = 1124, GOOF = 1.050, μ= 1.201 mm-1, the final R = 0.0376 and w R = 0.1000 for 3626 observed reflections with I 〉 2σ(I). 1 and 2 are connected through hydrogen bonding interactions to generate 2D and 3D supramolecular structures, respectively. Moreover, the preliminary antibacterial activities of 1 and 2 against the gram positive bacteria(S. aureus, C. albicans and B. subtilis) and gram negative bacteria(E. coli and P. aeruginosa) have been tested by using the microdilution method, and the results indicate that 2 is more active than 1 against the tested bacteria. 展开更多
关键词 pyrazole carboxylic acid copper compound helix chain crystal structure antibacterial activity
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Using benzene carboxylic acids to prepare zirconium-based catalysts for the conversion of biomass-derived furfural 被引量:1
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作者 Huacong Zhou Yufei Sha +6 位作者 Zhenhuan Xiao Lu Li Jianmin Hao Keli Yang Na Li Runxia He Quansheng Liu 《International Journal of Coal Science & Technology》 EI 2018年第4期464-472,共9页
Benzene carboxylic acid (BCAs) are common and useful chemical blocks, which can be derived from the abundant low rank coals (LRCs) via oxidative degradation. In this work, we proposed a novel strategy to utilize BCAs ... Benzene carboxylic acid (BCAs) are common and useful chemical blocks, which can be derived from the abundant low rank coals (LRCs) via oxidative degradation. In this work, we proposed a novel strategy to utilize BCAs as raw materials to prepare catalysts with transition metal zirconium, and the prepared catalysts were applied into the conversion of the renewable biomass resources. Typical model BCAs in the oxidative products of LRCs, including pyromellitic acid, trimesic acid (TMSA), trimellitic acid, and benzoic acid, were used as the block to construct the Zr- BCAs catalysts. The chemoselective conversion of furfural into furfuryl alcohol (FAL). an important reaction in the biomass conversion chain, is chosen to evaluate the activity of the catalysts. The preparation conditions of the catalysts and experiment factors during the reaction were systematically investigated. The prepared catalysts were characterized by SEM, TEM, XRD and TG-DTG. The results showed that the prepared catalysts were efficient for the conversion of furfural into FAL, among which Zr-TMSA gave the highest activity. Zr-TMSA could be recycled for ten times without obvious deactivation, indicating an excellent stability. The strategy proposed in this work may be beneficial for the value-added utilization of both LRCs and biomass resources. 展开更多
关键词 BENZENE carboxylic ACIDS Low RANK COALS ZIRCONIUM catalyst Biomass FURFURAL
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Synthesis and Properties of Ternary Europium Complexes with Aromatic Carboxylic Acid and Nitrogen-Containing Heterocyclic Ligand 被引量:1
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作者 Ma Ruixia Wang Ruifen +1 位作者 Wang Shuping Zhang Jianjun 《Journal of Rare Earths》 SCIE EI CAS CSCD 2006年第3期275-275,共1页
Seven ternary Eu (m) complexes were synthesized with aromatic carboxylic acid (benzoic acid, phenylacetic acid, phenylpropionic acid and cinnamic acid) as the first ligand and 1,10-phenanthro- line or 2,2'-dipyri... Seven ternary Eu (m) complexes were synthesized with aromatic carboxylic acid (benzoic acid, phenylacetic acid, phenylpropionic acid and cinnamic acid) as the first ligand and 1,10-phenanthro- line or 2,2'-dipyridyl as the second ligand. The ternary Eu( Ⅲ ) complexes were characterized by elemental analysis, IR and TG-DTG methods. In these complexes, the Eu (Ⅲ) ions are bonded to the oxygen atoms of carboxylate and the nitrogen atoms of neutral ligands. Four complexes whose second ligand is 1,10- phenanthrolin have fine thermal stability. Excitation and luminescence spectra of the tide complexes reveal that the fluorescence of the complexes in which 1,10- phenanthrolin as the second ligand are more intensive than those complexes in which 2, 2'-dipyridyl as the second ligand. The order of the strongest emission peak of seven ternary complexes is: Eu(β-PPA)3phen 〉 Eu(BA)3phen 〉 Eu(PLA)3phen 〉 Eu(BA)3bipy 〉 Eu ( PEA)3bipy 〉 Eu ( CA )3phen · H2O 〉 Eu ( CA )3bipy (BA : benzoic ; PEA : phenylacetic ; β-PPA : 展开更多
关键词 aromatic carboxylic acid EUROPIUM ternary complex thermal decomposition fluorescence spectra rare earths
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Robust cobalt oxide catalysts for controllable hydrogenation of carboxylic acids to alcohols 被引量:1
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作者 Song Song Dong Wang +5 位作者 Lu Di Chuanming Wang Weili Dai Guangjun Wu Naijia Guan Landong Li 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2018年第2期250-257,共8页
The selective catalytic hydrogenation of carboxylic acids is an important process for alcohol production,while efficient heterogeneous catalyst systems are still being explored.Here,we report the selective hydrogenati... The selective catalytic hydrogenation of carboxylic acids is an important process for alcohol production,while efficient heterogeneous catalyst systems are still being explored.Here,we report the selective hydrogenation of carboxylic acids using earth‐abundant cobalt oxides through a reaction‐controlled catalysis process.The further reaction of the alcohols is completely hindered by the presence of carboxylic acids in the reaction system.The partial reduction of cobalt oxides by hydrogen at designated temperatures can dramatically enhance the catalytic activity of pristine samples.A wide range of carboxylic acids with a variety of functional groups can be converted to the corresponding alcohols at a yield level applicable to large‐scale production.Cobalt monoxide was established as the preferred active phase for the selective hydrogenation of carboxylic acids. 展开更多
关键词 Selective hydrogenation carboxylic acids ALCOHOLS Cobalt oxides Reaction‐controlled catalysis
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Theoretic Simulation of Pr^(3+) and Nd^(3+) Complexes with αHydroxyl Carboxylic Acids 被引量:1
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作者 卢加春 徐元植 张利兴 《Journal of Rare Earths》 SCIE EI CAS CSCD 1999年第3期174-177,共4页
The potential energy difference of trivalent Pr/Nd complex ions with various α hydroxyl carboxylic acids were computed by molecular mechanics plus(MM +) model. Its relationships with the steric hindrance of the... The potential energy difference of trivalent Pr/Nd complex ions with various α hydroxyl carboxylic acids were computed by molecular mechanics plus(MM +) model. Its relationships with the steric hindrance of the coordinating lignads and with the separation factor of Pr/Nd were discussed. It is found that the MM + model can be used for selecting and designing ligand as effective eluant, with which Pr 3+ and Nd 3+ can be separated by ion exchange chromatography. 展开更多
关键词 Rare earths PRASEODYMIUM NEODYMIUM Molecular mechanics plus model α hydroxyl carboxylic acids
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Long-chain alkanol-alkyl carboxylic acid-based low-viscosity hydrophobic deep eutectic solvents for one-pot extraction of anthraquinones from Rhei Radix et Rhizoma 被引量:1
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作者 Anqi Huang Wenwen Deng +3 位作者 Xiao Li Qutong Zheng Xuanxuan Wang Yuxiu Xiao 《Journal of Pharmaceutical Analysis》 SCIE CAS CSCD 2022年第1期87-95,共9页
Natural long-chain alkanol and alkyl carboxylic acid were used to prepare novel hydrophobic deep eutectic solvents(HDESs).These HDESs are liquid at room temperature and have low viscosity(<12.26 mPa·s),low pol... Natural long-chain alkanol and alkyl carboxylic acid were used to prepare novel hydrophobic deep eutectic solvents(HDESs).These HDESs are liquid at room temperature and have low viscosity(<12.26 mPa·s),low polarity(lower than that of methanol,ChCl-based deep eutectic solvents and other reported HDESs),and low density(<0.928 g/mL).A simple one-pot method based on a novel HDES-water two-phase extraction system was constructed for the extraction of weak-polarity bioactive components,anthraquinones,from Rhei Radix et Rhizoma.This HDES-based new extraction method does not consume hazardous organic solvents and can obtain a total anthraquinone yield of 21.52 mg/g,which is close to that obtained by the Chinese pharmacopoeia method(21.22 mg/g)and considerably higher than those by other reported HDESs-based extraction methods(14.20-20.09 mg/g,p<0.01).The high extraction yield can be mainly attributed to the severe destruction of the RRR cell walls by the extraction system and the excellent dissolving ability of novel HDESs for anthraquinones. 展开更多
关键词 Hydrophobic deep eutectic solvent Long-chain alkanol Long-chain alkyl carboxylic acid One-pot extraction Anthraquinone
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Boosting chiral carboxylic acid hydrogenation by tuning metal-MO_(x)-support interaction in Pt-ReO_(x)/TiO_(2) catalysts 被引量:1
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作者 Guang Gao Zelun Zhao +3 位作者 Jia Wang Yongjie Xi Peng Sun Fuwei Li 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 2022年第8期2034-2044,共11页
Engineering the surface microenvironment by tuning the binary interactions between a supported metal with a secondary metal oxide(MO_(x))or support has been a common method for improving the catalytic performance of s... Engineering the surface microenvironment by tuning the binary interactions between a supported metal with a secondary metal oxide(MO_(x))or support has been a common method for improving the catalytic performance of supported metal catalysts.However,few studies have investigated the ternary interactions among the metal,MO_(x),and support.Here,we report for the first time the formation of metal-MO_(x)-support interaction(MMSI)in reducible TiO_(2)-supported PtReO_(x) catalysts,affording 87% yield and 100% ee in the tandem hydrogenation of an aqueous chiral cyclohexane-1,2-dicarboxylic acid into the corresponding diol;the catalytic activity is eight times higher than that obtained with non-reducible support counterparts in the same reaction via traditional batch synthesis with multiple steps and unfriendly reagents.Detailed experimental and computational studies suggest that the TiO_(2) crystalline phase-dependent density of the oxygen vacancies induces different Pt-ReO_(x)-TiO_(2) interactions,which dominate the electron transfer therein and tune the adsorption strength of the carbonyl moiety of the substrate/intermediate,thus promoting the hydrogenation activity and selectivity.In addition,the strong MMSI endows the optimal rutile TiO_(2) supported PtReO_(x) catalyst with an outstanding lifetime of 400 h in a fixed-bed reactor under acidic aqueous conditions and ensures efficient applications in the selective hydrogenation of aliphatic dicarboxylic acids and functional carboxylic acids.This work provides a promising strategy for the development of efficient and stable supported catalysts for the selective hydrogenation of diverse C-O and C=O bonds. 展开更多
关键词 Metal-MO_(x)-support interaction Synergistic catalysis carboxylic acid HYDROGENATION Alcohols with chiral group
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Determination of Clopidogrel Carboxylic Acid in Human Plasma by LC-MS/MS 被引量:2
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作者 Mohamed El-Husseiny El-Sadek Samia Mahmoud Moustafa +1 位作者 Hussien Omar Kadi Abdul Moneim Ali Al-Hakami 《American Journal of Analytical Chemistry》 2011年第4期447-455,共9页
Background: Clopidogrel, is a thienopyridine derivative labeled for use to prevent thrombosis after coronary artery stenting. Pharmacokinetics of clopidogrel is studied indirectly by quantification of carboxylic acid ... Background: Clopidogrel, is a thienopyridine derivative labeled for use to prevent thrombosis after coronary artery stenting. Pharmacokinetics of clopidogrel is studied indirectly by quantification of carboxylic acid which is a major metabolite of Clopidogrel. Objective: The aim of this work is to develop and validate a rapid, simple and sensitive LC/MS/MS assay method for the determination of Clopidogrel carboxylic acid in human plasma using Clopidogrel-D4-carboxylic acid as internal standard. Methods: Analytes was extracted from 200 μl of plasma by a simple liquid-liquid extraction using diethyl ether – n-hexane (80:20, v/v). The chromatographic separations were achieved on a C18 column using Methanol, de-ionized water and formic acid as a mobile phase at flow rate of 0.5 ml/minute. Analysis was monitored by multiple reactions monitoring mode based on m/z transition of 308.10→113 for Clopidogrel carboxylic acid and 312.10→129 for internal standard. Result: The method had a total run time of about 4 minutes. The lower limit of quantification (LLOQ) was 25 ng/ml showing good linearity over the working range of 25 – 3000 ng/ml (r ≥ 0.999). The intra- and inter day accuracies were 90% - 98% and 92.138% - 96.889% respectively (deviation within acceptable range ≤ 10%).Conclusion: It was shown that this method is suitable for pharmacokinetic study following oral administration of Clopidogrel and can be successfully applied to the therapeutic drug monitoring of Clopidogrel in Clopidogrel-treated patients. 展开更多
关键词 CLOPIDOGREL CLOPIDOGREL carboxylic Acid Liquid CHROMATOGRAPHY TANDEM Mass SPECTROMETRY
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