检索结果-南通市图书馆

Transition metal clusters with precise numbers of atoms anchored on graphdiyne as multifunctional electrocatalysts for OER/ORR/HER:a computational study

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Rare Metals 2024年第7期43卷 3107-3117页

作者： Xin-Yang Liu Jing-Wei Liu Gang Li Jing-Xiang Zhao college of chemistry and chemical engineering Harbin Normal University

Subnanometer metal clusters play an increasingly important role in heterogeneous catalysis due to their high catalytic activity and selectivity.In this work,by means of the density functional theory（DFT） calculations,the catalytic activities of transition metal clusters with precise numbers of atoms supported on graphdiyne(TM1-4@GDY,TM=V,Cr,Mn,Fe,Co,Ni,Cu,Ru,Rh,Pd,Ir,Pt) were investigated for oxygen evolution reactions（OER）,oxygen reduction reactions（ORR） and hydrogen evolution reactions（HER）.The computed results reveal that the Pd2,Pd4and Pt1anchored graphdiyne can serve as trifunctional catalysts for OER/ORR/HER with the overpotentials of 0.49/0.37/0.06,0.45/0.33/0.12 and 0.37/0.43/0.01 V,respectively,while Pd1and Pt2@graphdiyne can exhibit excellent catalytic performance for water splitting（OER/HER） with the overpotentials of 0.55/0.17 and 0.43/0.03 V.In addition,Ni1and Pd3anchored GDY can perform as bifunctional catalysts for metal-air cells（OER/ORR） and fuels cells（ORR/HER） with the overpotentials of 0.34/0.32 and 0.42/0.04 V,respectively.Thus,by precisely controlling the numbers of atoms in clusters,the TM1-4anchored graphdiyne can serve as promising multifunctional electrocatalysts for OER/ORR/HER,which may provide an instructive strategy to design catalysts for the energy conversation and storage devices.

关键词： Density functional theory Graphdiyne Single-cluster catalysts Multifunctional electrocatalysts Overpotential

Catalytically generated noncovalent ammonium dienolate:a versatile platform for the development of organocatalytic asymmetric cascade reactions

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Science China chemistry 2024年第8期67卷 2524-2546页

作者： Jun-Bing Lin Dong-Sheng Ji Peng-Fei Xu State Key Laboratory of Applied Organic chemistry College of Chemistry and Chemical Engineering Lanzhou University Shaanxi Key Laboratory of chemical Reaction engineering College of Chemistry and Chemical Engineering Yan'an University

Organocatalytic cascade reactions represent a powerful strategy for the rapid construction of complex chiral molecules with multiple stereocenters from simple substrates under mild conditions. The intriguing structural feature and diverse reactivity of catalytically generated dienolate species render them competent and versatile intermediates for the development of practical and valuable cascade reactions. Over the past years, a plethora of innovative and pioneering noncovalent ammonium dienolatemediated cascade reactions have been designed and implemented under the catalysis of chiral organocatalysts, making dienolate activation a general, robust, and complementary method for the functionalization of unsaturated carbonyl compounds and related substances. This review illustrates the recent advances in organocatalytic noncovalent ammonium dienolate-mediated cascade reactions(mainly from 2010 to 2023), including the cascade transformations of ammonium dienolates directly generated from unsaturated ketone/aldehyde, ester/lactone/azlactone, amide/lactam/pyrazolone/oxindole, and alkylidene nitrile compounds. The contents are arranged based on the reaction types of the ammonium dienolates, with an emphasis on cascade 2,5-, 3,5-, and 4,5-difunctionalizations of these intermediates. Furthermore, other cascade reactions involving the 1,3-, 2,3-, and even more complex 3,4,5-reactivities of ammonium dienolates were also discussed. The reaction pathway, reaction stereoinduction, and synthetic applications of the ammonium dienolate-mediated cascade reactions were highlighted throughout the article. As a stimulating and ever-growing research area, the organocatalytic noncovalent ammonium dienolate-mediated cascade reactions are expected to continue demonstrating their magic power for constructing chiral targets in the future and further expanding the boundaries of asymmetric catalysis.

关键词： ammonium dienolate asymmetric catalysis cascade reaction difunctionalization organocatalysis

FeNi Prussian blue analogues on highly graphitized carbon nanosheets as efficient glucose sensors

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Rare Metals 2024年第6期43卷 2730-2738页

作者： Jin-Hang Xue Qiu-Hong Sun Cheng Han Yuan-Dong Yang Shao-Jie Xu Qi-Peng Li Jin-Jie Qian college of Life and Environmental Science Wenzhou University college of chemistry and Materials engineering Wenzhou University college of chemistry and chemical engineering Zhaotong University

Meeting the continuous glucose monitoring requirements of individuals necessitates the research and development of sensors with high sensitivity and stability.In this study,a straightforward strategy was proposed for synthesizing ultra-thin oxygen-rich graphitized carbon nanosheets（denoted as GCS-O）.These nanosheets are obtained by calcining a topologically two-dimensional indium-based coordination polymer.Subsequently,the growth of FeNi Prussian blue analogue（PBA） on GCS-O effectively introduces active sites and increases the nitrogen content within the carbonaceous matrix.The resulting FeNi-PBA/GCS-O composite exhibits excellent glucose sensing performance with a broad linear range of 1 to 1300μmol·L-1.Meanwhile,it also achieves a high sensitivity of 2496 μA·mmol-1·L·cm-2,a limit of detection of 100nmol·L-1（S/N=3）,and commendable long-term durability.The relatively simple synthesis process,exceptional sensitivity,and satisfactory electrochemical sensing performance of FeNi-PBA/GCS-O open up new directions for biosensor applications.

关键词： Coordination polymer Carbon nanosheet Prussian blue analogue Surface reconstruction Glucose oxidation

Iron-nickel alloy particles with N-doped carbon “armor” as a highly selective and long-lasting catalyst for the synthesis of Nbenzylaniline molecules

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Nano Research 2024年第4期17卷 2308-2319页

作者： Gang Wang Longchao Sun Wanyi Liu Haijuan Zhan Shuxian Bi college of chemistry and chemical engineering Ningxia UniversityYinchuan 750021China

A scalable strategy for the convenient and rapid preparation of nitrogen-doped carbon-coated iron-based alloy catalysts was developed.By controlling the type and amount of metal salts in the precursor,various types of nitrogen-doped carbon-coated alloy catalysts can be prepared in a targeted manner.Fe_(2)Ni2@CN materials with small particle sizes and relatively homogeneous basic sites showed promising results in the N-alkylation reaction of benzyl alcohol with aniline(optimum yield:99%).It is worth noting that the catalyst can also be magnetically separated and recovered after the reaction,and its performance can be regenerated through simple calcination.Furthermore,it was confirmed by kinetic experiments that the activation of C–H at the benzyl alcohol benzylic position is the rate-determining step(RDS).According to density flooding theory calculations,Fe_(2)Ni2@CN catalysts require less energy than other materials(Fe@CN and Ni@CN)for the RDS(dehydrogenation reaction)process.Therefore N-alkylation reactions are more easily carried out on Fe_(2)Ni2@CN catalysts,which may be the reason for the best catalytic activity of Fe-Ni alloy materials.These carbon-coated alloy materials will show great potential in more types of heterogeneous catalysis.

关键词： iron-nickel alloy catalyst N-alkylation reaction magnetic separation reaction path dehydrogenation reaction

Glutamicibacter nicotianae AT6:A new strain for the efficient biodegradation of tilmicosin

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Environmental Sciences 2024年第8期142卷 182-192页

作者： Huijuan Li Hao Zhou Liling Fan Long Meng Yanyun Zhao Lanmei Zhao Bo Wang college of chemical and Biological engineering Shandong University of Science and TechnologyQingdao 266590China college of chemistry and chemical engineering Heze UniversityHeze 274015China college of Safety and Environmental engineering Shandong University of Science and TechnologyQingdao 266590China

The degradation of tilmicosin(TLM),a semi-synthetic 16-membered macrolide antibiotic,has been receiving increasing attention.Conventionally,there are three tilmicosin degradation methods,and among them microbial degradation is considered the best due to its high efficiency,eco-friendliness,and low cost.Coincidently,we found a new strain,Glutamicibacter nicotianae sp.AT6,capable of degrading high-concentration TLM at 100 mg/L with a 97%removal efficiency.The role of tryptone was as well investigated,and the results revealed that the loading of tryptone had a significant influence on TLM removals.The toxicity assessment indicated that strain AT6 could efficiently convert TLM into less-toxic substances.Based on the identified intermediates,the degradation of TLM by AT6 processing through two distinct pathways was then proposed.

关键词： Tilmicosin Glutamicibacter nicotianae Biodegradation Degradation pathway Pharmaceutical wastewater

维普期刊数据库

Micro/nanoelectrode-based electrochemical methodology for single cell and organelle analysis

在线全文

学校读者我要写书评

暂无评论

Nano Research 2024年第1期17卷 196-206页

作者： Chuchu Xu De Yang Yuchan Wang Ruolin Liu Fan Wang Zhongqun Tian Keke Hu Department of chemistry College of Chemistry&Chemical EngineeringXiamen UniversityXiamen 361005China

Cells are the basic unit of life.Electrochemical analysis of single cells/organelles is essential for uncovering the molecular mechanisms of physiological and pathological processes that are difficult to elucidate on a larger scale.This paper provides an overview of the commonly used fabrication methods for micro/nanoelectrodes applied in the investigations of single cells/organelles as well as the corresponding electrochemical measurements over the last four years including extracellular measurement,combination of extra and intracellular measurement,intracellular reactive oxygen species and reactive nitrogen species(ROS/RNS)measurement,and isolated organelles measurement.

关键词： single cell/organelle micro/nanoelectrode electrochemical measurement chemical transmitters

Genome mining of sulfonated lanthipeptides reveals unique cyclic peptide sulfotransferases

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Acta Pharmaceutica Sinica B 2024年第6期14卷 2773-2785页

作者： Meng Wang Wen-Wei Li Zhe Cao Jianong Sun Jiang Xiong Si-Qin Tao Tinghong Lv Kun Gao Shangwen Luo Shi-Hui Dong State Key Laboratory of Applied Organic chemistry College of Chemistry and Chemical EngineeringLanzhou UniversityLanzhou 730000China

Although sulfonation plays crucial roles in various biological processes and is frequently utilized in medicinal chemistry to improve water solubility and chemical diversity of drug leads,it is rare and underexplored in ribosomally synthesized and post-translationally modified peptides(RiPPs).Biosynthesis of RiPPs typically entails modification of hydrophilic residues,which substantially increases their chemical stability and bioactivity,albeit at the expense of reducing water solubility.To explore sulfonated RiPPs that may have improved solubility,we conducted co-occurrence analysis of RiPP class-defining enzymes and sulfotransferase(ST),and discovered two distinctive biosynthetic gene clusters(BGCs)encoding both lanthipeptide synthetase(LanM)and ST.Upon expressing these BGCs,we characterized the structures of novel sulfonated lanthipeptides and determined the catalytic details of LanM and ST.We demonstrate that SslST-catalyzed sulfonation is leader-independent but relies on the presence of A ring formed by LanM.Both LanM and ST are promiscuous towards residues in the A ring,but ST displays strict regioselectivity toward Tyr5.The recognition of cyclic peptide by ST was further discussed.Bioactivity evaluation underscores the significance of the ST-catalyzed sulfonation.This study sets up the starting point to engineering the novel lanthipeptide STs as biocatalysts for hydrophobic lanthipeptides improvement.

关键词： Lanthipeptides Sulfotransferases Sulfonation Biosynthesis Genome mining

Tough lanthanide luminescent hydrogel for nitroaromatics detection

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Rare Earths 2024年第2期42卷 293-302,I0003页

作者： Shu Xie Fei Li Fengyi Liu Quanqing Xu Xufeng Zhang college of chemistry and chemical engineering Yunnan Normal UniversityKunming650092China

Luminescent hydrogels have received considerable attention in the application of sensors.Nitroaro matics are harmful to human health and can be carcinogenic.Some skin allergies and central nervous system injuries may also be attributed to the over exposure to nitroaromatics.Thus,nitroaromatics sensor with fast detection and low detection limit is highly desirable.Herein,novel tough hydrogels were prepared by introducing hydrogen bonds and covalent bonds into the interpenetrating networks of modified chitosan and poly(vinyl alcohol)(PVA) via frozen-thawing induced chemical cross-linking.The synthesized hydrogels exhibit high mechanical strength(0.23 MPa tensile strength at 140% tensile strain,1.0 MPa compressive strength at 80% compressive strain).Strong green emission was realized by energy transfer from the modified chitosan to Tb^(3+)via the so-called "antenna effect." The prepared luminescent hydrogels show an excellent detection effect on nitroaromatic compounds and its detection limit can reach ppm-level.The hydrogels also exhibit good reversibility and a fast "off-on" fluorescence switching process.This work may open up a new way for the development of stable,rapid,and reusable sensors for the detection of harmful nitroaromatics.

关键词： Hydrogels Lanthanide Luminescence Nitroaromatics Sensors Rare earths

维普期刊数据库

Molecular solid solution of lanthanide-titanium-oxo clusters with enhanced photocatalytic hydrogen evolution

在线全文

学校读者我要写书评

暂无评论

Science China chemistry 2024年第2期67卷 529-535页

作者： Rong Chen Chao-Long Chen Hui Zhang Zi-Han Wang Fu-Li Sun Ming-Hao Du Gui-Lin Zhuang Cheng Wang La-Sheng Long Lan-Sun Zheng Xiang-Jian Kong Collaborative Innovation Centre of chemistry for Energy Materials State Key Laboratory of Physical chemistry of Solid Surfaces and Department of chemistry College of Chemistry and Chemical EngineeringXiamen UniversityXiamen361005China college of chemical engineering Zhejiang University of TechnologyHangzhou310032China

Molecular solid solutions of metal clusters containing different metal centers with well-defined structures can accurately regulate the HOMO-LUMO gap,but are rarely available.Herein,a series of colorless lanthanide-titanium-oxo clusters Ln_(2)Ti_4(μ_(2)-O)_(2)(μ_(3)-O)_4(Piv)_(10)(THF)_(2)(Ln_(2)Ti_4,Ln = Eu,Gd,Tb,and Ce,HPiv = pivalic acid) were synthesized by the reaction of pivalic acid with Ln(Ac)_(3) and titanium isopropoxide.The light yellow crystal of cluster solid solutions Eu_(2)Ti_(4-x)Cd_(x),containing a mixture of Eu_(2)Ti_4 and Eu_(2)Ti_(3)Cd,was obtained by in situ doping Cd^(2+) and S^(2–).Eu_(2)Ti_(3.92)Cd_(0.08) displays efficient photocatalytic hydrogen evolution activity without a co-catalyst,which is up to 2.6 times that of Eu_(2)Ti_4.Femtosecond time-resolved transient absorption spectroscopy and spin-polarized density functional calculations showed that the enhanced photocatalytic performance of Eu_(2)Ti_(4-x)Cd_(x) can be attributed to the narrower HOMO-LUMO gap and lower LUMO position than that of Eu_(2)Ti_4.This studyprovides an in situ doping method to realize the simple preparation of cluster solid solution.

关键词： molecular solid solution lanthanide-titanium-oxo clusters photocatalytic hydrogen evolution

维普期刊数据库