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STUDIES ON THE PRENYLFLAVONOIDS PART V.SYNTHESIS OF(±)LESPEDEZAFLAVANONE D 被引量:4
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作者 Fang Jie ZHANG Hua Wu SHAO Yu Lin LI Satate key Laboratory of Applied Organic Chemistry,Lanzhou University,Lanzhou 730000 《Chinese Chemical Letters》 SCIE CAS CSCD 1993年第4期283-284,共2页
(±)Lespedezaflavanone D,8,5'-di(γ,γ-dimethylallyl)-5,7,2',4'-tetrahydroxyflavanone,has been synthesized by the condensation of 4,6-dimethoxymethoxy-3-(γ,γ-dimethylallyl)-2-hydroxy- acetophenone wi... (±)Lespedezaflavanone D,8,5'-di(γ,γ-dimethylallyl)-5,7,2',4'-tetrahydroxyflavanone,has been synthesized by the condensation of 4,6-dimethoxymethoxy-3-(γ,γ-dimethylallyl)-2-hydroxy- acetophenone with 2,4-dimethoxymethoxy-5-(γ,γ-dimethylallyl)benzaldehydc followed by cyclization and demethoxymethylation. 展开更多
关键词 LESPEDEZAFLAVANONE D STUDIES ON THE PRENYLFLAVONOIDS PART V.synthesis OF PPM WANG FAB
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STUDY ON BINUCLEAR COPPER(I)COMPLEXES III.SYNTHESIS,CHARACTERIZATION AND ELECTROCHEMISTRY OF DICHLORO-TRIS(4-VINYLPYRIDINE)-DICOPPER(I)COMPLEX
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作者 Zhen Feng XI Rui Na YANG Dou Man JIN Henan Institute of Chemistry,Zhengzhou 450003 《Chinese Chemical Letters》 SCIE CAS CSCD 1990年第2期185-186,共2页
Recent years,many novel complexes have been prepared by using hetero-bidentate ligands.However,complexes with such ligands as 4-vinylpyridine which has two different coordinating sites have not been reported,and only ... Recent years,many novel complexes have been prepared by using hetero-bidentate ligands.However,complexes with such ligands as 4-vinylpyridine which has two different coordinating sites have not been reported,and only a few complexes of Cu(I)have been published^(1-3).The title complex Cu_2(C_5H_4N·CH=CH_2)_3Cl was prepared and characterized by elemental analyses,ICP,IR,and electronic spectra.Its conductivity,oxidation potential and reduction potential were measured. 展开更多
关键词 I)COMPLEXES III.synthesis CHARACTERIZATION AND ELECTROCHEMISTRY OF DICHLORO-TRIS STUDY ON BINUCLEAR COPPER I)COMPLEX DICOPPER VINYLPYRIDINE Cu CI III
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Novel Phosphonoacetic Acid Derivatives.Synthesis of N-(Ethoxycarbonylmethylphosphonyl)-α-Amino Esters and-α-Amino Phosphonic Acid Esters and Their Bioactivities
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作者 Hui Ying LI Kang Tai REN Ru Yu CHEN(Institute of Elemento-Organic Chemistry, Nankai University, Tianjin 300071) 《Chinese Chemical Letters》 SCIE CAS CSCD 1997年第12期0-0,0-0,共4页
A series of novel phosphonoacetic acid derivatives, N-(ethoxycarbonylmethy-ethoxyphosphonyl)-α-amino acid esters and α-amino phosphonates, were synthesized via the reaction of the corresponding phosphonyl chloride ... A series of novel phosphonoacetic acid derivatives, N-(ethoxycarbonylmethy-ethoxyphosphonyl)-α-amino acid esters and α-amino phosphonates, were synthesized via the reaction of the corresponding phosphonyl chloride with amino acid ester hydrochlorides or amino phosphonates in the presence of a base. The preliminary bioassay shows that some compounds show significant anti-viral activity against tobacco mosaic virus (TMV) 展开更多
关键词 Novel Phosphonoacetic Acid Derivatives.synthesis of N cm PN Amino Phosphonic Acid Esters and Their Bioactivities Ethoxycarbonylmethylphosphonyl Amino Esters and
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Synthesis on Multifunctional Groups and Multibranched Compounds Ⅷ.Synthesis of Dendritic Polyestrone
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作者 Jian CHEN Ling Ling WENG Hu ZHENG(School of Pharmacy, West China University of Medical Sciences, Chengdu 610041) 《Chinese Chemical Letters》 SCIE CAS CSCD 1998年第5期451-453,共3页
In this article, using the four-directional core and quaternary carbon branching point, adendritic polyestrone with twelve estrone units was synthesized by convergent strategy. Itsstructure was confirmed by IR and NMR... In this article, using the four-directional core and quaternary carbon branching point, adendritic polyestrone with twelve estrone units was synthesized by convergent strategy. Itsstructure was confirmed by IR and NMR spectra. 展开更多
关键词 DENDRIMER polyestrone synthesis
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Nickel Group Complexes With Thiolate or/and Phosphine Ligands.Synthesis and X-ray CrystalStructure of 〔Ni_2(pdt)_2 (PEt_3)_2〕
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作者 CAO Rong HONG Mao-Chun +1 位作者 JIANG Fei-Long LIU Han-Qin (State Key Laboratory of Structural Chemistry, Fujian institute of Research onthe Structure of Matter, Chinese Academy of Sciences, Fuzhou 350002, Fujian) 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 1997年第1期36-41,共6页
The reactions of nickel group M2+ with thiolate and phosphine inMeOH yield mononuclear and binuclear complexes. Ni2 (PEt3 ), (pdt )2 (pdt = 1, 2propanedithiolate) was synthesized and analyzed by single crystal X--ray ... The reactions of nickel group M2+ with thiolate and phosphine inMeOH yield mononuclear and binuclear complexes. Ni2 (PEt3 ), (pdt )2 (pdt = 1, 2propanedithiolate) was synthesized and analyzed by single crystal X--ray diffractionmethod. The complex is monoclinic with space group P21 /c, Mr= 566. 16 a = 18. 737(5), b=9. 906(4), c= 14. 540(10) A; V=2697. 65 A3, Dc = 1. 394 g/cm3 for Z=4; the final R(Rw) = 0. 062(0. 072). The complex is a dimer, where the Ni atoms arelinked by two sulphur atoms from SC3H6S2- (pdt2- ) ligands and each Ni atom is fourcoordinated by one P and three S atoms with distorted square--planar geometry. The Ni--Ni distance is 3. 025 .A, the average Ni--S, Ni--P distances are 2. 187 and 2. 194A, respectively. 展开更多
关键词 nickel complex synthesis crystal structure
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Search for New AntiphytovirucidesⅣ.Synthesis of 2-(2'-Hydroxyphenyl)-5(6)-substituted benzimidazole Derivatives
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作者 Huang Xiaoling, Jiang Hong, Qu Fanqi, Zhong Min Department of Chemistry, Wuhan University, Wuhan 430072,China National Laboratory of Elemento Organic Chemistry, Nankai University, Tianjin 300071,China 《Wuhan University Journal of Natural Sciences》 CAS 1997年第1期70-72,共3页
A convenient method to synthesize substituted 2 (2' hydroxyphenyl) benzimidazoles is reported. Six title compounds have been synthesized by the reaction of salicylic acid and 4 substituted o phenylene... A convenient method to synthesize substituted 2 (2' hydroxyphenyl) benzimidazoles is reported. Six title compounds have been synthesized by the reaction of salicylic acid and 4 substituted o phenylenediamine in the presence pyridine POCl 3 . Three compounds were tested as plant virucide against tobacco mosaic virus and they exhibited some activities. 展开更多
关键词 substituted 2 (2' hydroxyphenyl)benzimidazole synthesis plant virucide CONDENSATION
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STUDIES ON THE PRENYLFLAVONOIDS PART Ⅲ.SYNTHESIS OF(±)EUCHRENONE A_8
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作者 Hua Wu SHAO Fang Jie ZHANG Yu Lin LI State key Laboratory of Applied Organic Chemistry,Lanzhou University,Lanzhou 730000 《Chinese Chemical Letters》 SCIE CAS CSCD 1993年第3期189-194,共6页
(±)Euchrenonc a_8,7,2'-dihydroxy-8,5'-di(γ,γ-dimethylallyl)-4'-methoxyflavanone,has been synthesized by the condensation of 2-hydroxy-4-methoxymethoxy-3-(γ,γ-dimethylallyl) acctophenonc with 4-met... (±)Euchrenonc a_8,7,2'-dihydroxy-8,5'-di(γ,γ-dimethylallyl)-4'-methoxyflavanone,has been synthesized by the condensation of 2-hydroxy-4-methoxymethoxy-3-(γ,γ-dimethylallyl) acctophenonc with 4-methoxy-2-methoxymethoxy-5-(γ,γ-dimethylallyl)benzaldchyde followed by cyclization and demethoxymethylation. 展开更多
关键词 STUDIES ON THE PRENYLFLAVONOIDS PART synthesis OF EUCHRENONE A8
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STUDIES ON THE PRENYLFLAVONOIDS PARTⅡ.SYNTHESIS OF EUCHRENONE A_7
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作者 Yu Lin LI Fang Jie ZHANG Hua Wu ShAO Shao Bai LI State Key Laboratory of Applied Organic Chemistry,Lanzhou University,Lanzhou 730000 《Chinese Chemical Letters》 SCIE CAS CSCD 1992年第1期3-4,共2页
Euchrcnonc a_7 has been prcparcd by condensation of 2-hydroxy-4- mcthoxy-3-prcnylacctophcnone with 2,4-dimethoxymethoxybenzaldehyde followed by cyclization and demethoxymethylation.
关键词 PPM OCH STUDIES ON THE PRENYLFLAVONOIDS PART synthesis OF EUCHRENONE A7
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Recent Progresses in Synthesis of Cyclic Polymers in Large-scale and Some Functionalized Composites
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作者 QU Kairu GUO Lyuzhou +3 位作者 WANG Wenbin YAN Xuzhou CAO Xuezheng YANG Zhenzhong 《高等学校化学学报》 北大核心 2026年第1期42-57,共16页
Among various architectures of polymers,end-group-free rings have attracted growing interests due to their distinct physicochemical performances over the linear counterparts which are exemplified by reduced hydrodynam... Among various architectures of polymers,end-group-free rings have attracted growing interests due to their distinct physicochemical performances over the linear counterparts which are exemplified by reduced hydrodynamic size and slower degradation.It is key to develop facile methods to large-scale synthesis of polymer rings with tunable compositions and microstructures.Recent progresses in large-scale synthesis of polymer rings against single-chain dynamic nanoparticles,and the example applications in synchronous enhancing toughness and strength of polymer nanocomposites are summarized.Once there is the breakthrough in rational design and effective large-scale synthesis of polymer rings and their functional derivatives,a family of cyclic functional hybrids would be available,thus providing a new paradigm in developing polymer science and engineering. 展开更多
关键词 Cyclic polymer Large-scale synthesis Single-chain nanoparticle Performance Composite
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Batch and continuous-flow asymmetric synthesis of d-pantothenic acid precursor enabled by immobilized ketoreductase mutant
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作者 Pan Hu Xiaofan Wu +6 位作者 Yi An Xianjing Zheng Liang Gao Yuan Tao Yajiao Zhang Zedu Huang Fener Chen 《Chinese Chemical Letters》 2026年第2期471-476,共6页
We report an immobilized enzyme-catalyzed batch and continuous-flow synthesis of optically pure ethyl(R)-pantothenate((R)-PaOEt),the direct precursor of d-pantothenic acid.Firstly,a ketoreductase mutant designated as ... We report an immobilized enzyme-catalyzed batch and continuous-flow synthesis of optically pure ethyl(R)-pantothenate((R)-PaOEt),the direct precursor of d-pantothenic acid.Firstly,a ketoreductase mutant designated as M2,carrying two-point mutations of F97L and M242F relative to the wild-type SSCR,was constructed by site-directed mutagenesis,exhibited simultaneously improved activity toward ethyl 2′-ketopantothenate(K-PaOEt)and isopropanol,and could effectively catalyze the stereoselective reduction of K-PaOEt to(R)-PaOEt by using isopropanol as the sacrificial co-substrate to regenerate NADPH.After screening six commercially available carriers,an amino resin LXTE-700 was identified as the best solid support for the immobilization of M2 via the glutaraldehyde activation method.Upon optimization of the immobilization process and reaction conditions,the fabricated immobilized enzyme M2@amino resin demonstrated excellent recyclability and reusability,with the complete conversion of K-PaOEt to(R)-PaOEt being still realized after 12 cycles of reuse.Finally,M2@amino resin-catalyzed synthesis of(R)-PaOEt was successfully implemented in continuous-flow,accomplishing a 6.3 times higher space-time yield than that with the batch synthesis(529.2 versus 84 g L^(-1) d^(-1)).Our developed flow biocatalysis system also features an outstanding operational stability,as evidenced by the 100%conversion rate achieved after 15 consecutive days of operation. 展开更多
关键词 Asymmetric synthesis Continuous flow synthesis Enzyme immobilization KETOREDUCTASE D-Pantothenic acid
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Total synthesis of ADPr-ATP and evaluation of the antiviral activity of pRib-AMP prodrug
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作者 Tiantian Zhang Hanbo Liu +1 位作者 Junbiao Chang Yonggang Meng 《Chinese Chemical Letters》 2026年第2期419-423,共5页
ADPr-ATP is a natural nucleotide with three sugar rings and five pentavalent phosphorus,and can be produced through TIR-catalyzed ADP-ribosylation reactions for plant immunity.Here,we report the first total synthesis ... ADPr-ATP is a natural nucleotide with three sugar rings and five pentavalent phosphorus,and can be produced through TIR-catalyzed ADP-ribosylation reactions for plant immunity.Here,we report the first total synthesis of ADPr-ATP(1)with a total yield of 6.4%through 14 steps,featuring late-stage P(V)−N activation reaction of pyrophosphate(4)and 5′-phosphoromorpholidate(25).The protected adenosine 5′-phosphoromorpholidate(24)was prepared on the basis of a scalable to adenosine 5′′-monophosphate(2).The construction of P(V)−N bond in phosphoramidate is esteemed as a critical step as they are sufficiently stable in deprotection reactions.The chemical synthesis of ADPr-ATP can offer an appealing alternative to traditional enzymatic synthesis and fractionation methods.Furthermore,the pRib-AMP and its prodrug are also synthesized to evaluate cytotoxicity and anti-influenza activity in vitro. 展开更多
关键词 ADPr-ATP NUCLEOTIDE IMMUNITY Total synthesis ANTI-INFLUENZA
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Synthesis and insecticidal activity evaluation of sulfonamide derivatives oriented by atom replacement strategy
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作者 Hao Qian Xinru Tan +8 位作者 Guixun Wu Lei Wang Ziyu Wang Hongxiang Liu Mei Tian Minjie Zhang Keyin Yu Wenjun Wu Jiwen Zhang 《Advanced Agrochem》 2026年第1期49-57,共9页
The single-atom replacement strategy is a typical approach which just converts elements in lead compounds into their analogues with very small chemical changes.In this research,we implemented this strategy to modify t... The single-atom replacement strategy is a typical approach which just converts elements in lead compounds into their analogues with very small chemical changes.In this research,we implemented this strategy to modify the sulfonamide scaffold identified in our previous work,and resulting in the synthesis of 40 novel sulfonamide derivatives not previously reported in the literature.The insecticidal activities of these compounds against the Mythimna separata and Plutella xylostella were assessed.Our findings indicate that the pyridine sulfonamide structure significantly enhances insecticidal efficacy.Specifically,compound 7c exhibited LC 50 values of 0.157 and 0.256 mg/mL against the M.separata and P.xylostella,which significantly increased 97-and 41-fold compared to celangulin V,respectively.The experimental results revealed that pyridine sulfonamide analogues could serve as potential green insecticides. 展开更多
关键词 SULFONAMIDE synthesis Insecticidal activity Atom replacement Celangulin V
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Benzyl sulfide, sulfoxide and sulfinate metabolites from Gastrodia elata and their synthesis, derivatization and anti-inflammatory activity
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作者 Chengbo Xu Lei Wang +7 位作者 Xue Zhou Shuai Shao Chengjuan Chen Xiaoqiang Lei Tiantai Zhang Jiachen Zi Jiangong Shi Qinglan Guo 《Chinese Journal of Natural Medicines》 2026年第3期365-372,共8页
Five novel sulfur-containing benzyl metabolites, designated as gastrabenzylsulfoxides A and B(1 and 2), gastrabenzylsulfinate A(3) and gastrabenzylsulfides A and B(4 and 5), along with four known compounds(6-9), were ... Five novel sulfur-containing benzyl metabolites, designated as gastrabenzylsulfoxides A and B(1 and 2), gastrabenzylsulfinate A(3) and gastrabenzylsulfides A and B(4 and 5), along with four known compounds(6-9), were isolated from the aqueous extracts of Gastrodia elata.Compounds 1 and 4 are 4-hydroxy-3-(4′-hydroxybenzyl)benzyl-substituted sulfoxide and sulfide, respectively, which are unprecedented in natural products. Compound 3 represents a rare sulfinate. Several isolates and their sulfone and disulfide analogs(10-13) were synthesized to evaluate their anti-inflammatory activity. Notably, the synthesized sulfone 10 demonstrated significant alleviation of symptoms in multiple in vivo inflammatory models. 展开更多
关键词 Gastrodia elata Sulfur-bearing benzyl metabolites synthesis Anti-inflammatory activity
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Novel advancements in synthesis,modulation,and potential applications of conjugated microporous polymer-based materials
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作者 Hamid Ali Obaid Iqbal +9 位作者 Muhammad Sadiq Yumeng Cheng Xiao Yan Basem Al Alwan Atef El Jery Hameed ur Rahman Yongteng Qian Asif Hayat Dewu Yue Zeeshan Ajmal 《Nano Materials Science》 2026年第1期117-174,共58页
Conjugated microporous polymers(CMPs)are a unique class of organic porous materials characterized byπ-conjugated structures and permanent micropores,distinguishing them from non-porous polymers and conventionalπ-con... Conjugated microporous polymers(CMPs)are a unique class of organic porous materials characterized byπ-conjugated structures and permanent micropores,distinguishing them from non-porous polymers and conventionalπ-conjugated polymers.CMPs offer extensive versatility in synthetic approaches,enabling the synthesis of cross-linked and mesoporous structures.Advances in chemical processes,structural design,and synthesis methodologies have been developed,resulting in a diverse range of CMPs with unique configurations and properties,contributing to the fast expansion of the field.CMPs are particularly notable for their ability to enable the competitive utilization ofπ-conjugated structures within mesoporous configurations,making them valuable for investigations across various domains.They have shown considerable promise in addressing fuel and environmental challenges,demonstrated by their exceptional performance in applications such as vapor adsorption,heterogeneous catalysis,light emission,light harvesting,and energy generation.This review examines the chemical engineering principles underlying CMPs,including synthesis approaches,systemic research advancements,multifunctional investigations boundaries,potential applications,and progress in synthesis,dimensionality,and morphology studies.Specifically,it offers a comparative analysis of CMPs and linear polymeric materials,aiding in the development of functional polymers.Furthermore,this review explores the primary fundamental limitations of CMPs in fuel-related domains and discusses alternative strategies,including novel synthesis methods incorporating interactions and morphologies,to address these challenges.Ultimately,this assessment aims to provide a valuable and inspiring resource for professionals in the field of fuel management,guiding future research and development efforts. 展开更多
关键词 Conjugated microporous polymers synthesis reactions FUNCTIONALIZATION MORPHOLOGIES Potential applications CATALYTIC
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Enantioconvergent reductive amidation of benzyl ammonium salts for synthesis of α-chiral amides
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作者 Saima Perveen Xicheng Wang +6 位作者 Tao Li Linghua Wang Shuai Zhang Yizhao Ouyang Xue Zhao Liang Xu Pengfei Li 《Chinese Chemical Letters》 2026年第1期300-305,共6页
α-Chiral amides are common in pharmaceuticals,agrochemicals,natural products,and peptides,prompting the need for new synthetic methods.Here,we introduce a nickel-catalyzed asymmetric reductive amidation method to syn... α-Chiral amides are common in pharmaceuticals,agrochemicals,natural products,and peptides,prompting the need for new synthetic methods.Here,we introduce a nickel-catalyzed asymmetric reductive amidation method to synthesizeα-chiral amides from benzyl ammonium salts and isocyanates.The key to success is using a chiral 2,2-bipyridine ligand(-)-Ph-SBpy,enabling high yield(up to 95%)and enantiomeric ratio(up to 98:2 er)under mild conditions.Addition of phenol prevents isocyanate polymerization by reversibly forming a carbamate intermediate,enhancing selectivity and efficiency.The synthetic utility is showcased through transformations of the enantioenriched amides,and the mechanism and enantioselectivity are supported by experimental and computational studies. 展开更多
关键词 α-Chiral amide AMIDATION Asymmetric synthesis Bipyridine ligand Nickel catalysis
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Scalable and rapid liquid synthesis of PtNi electrocatalyst for hydrogen evolution reaction
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作者 Liming Li Yanchang Liu +7 位作者 Peng Kang Donghui Feng Yuguang Zhang Hangxing Ren Jianrong Zeng He Zhu Qiang Li Xiaoya Cui 《Chinese Chemical Letters》 2026年第2期517-522,共6页
Structural engineering of Pt-based nanoalloys is crucial for the rational design and manufacturing of high-performance and low-cost electrocatalysts for hydrogen evolution reaction(HER).Here,we reported PtNi nanoparti... Structural engineering of Pt-based nanoalloys is crucial for the rational design and manufacturing of high-performance and low-cost electrocatalysts for hydrogen evolution reaction(HER).Here,we reported PtNi nanoparticles with a refined size of 2.71 nm and regular strains loaded on carbon black,synthesized using the high-temperature liquid shock(HTLS)method.This approach offers significant advantages over conventional synthesis methods,including high scalability,rapid reaction rates,and precise control over the size and shape of nanocrystals.Importantly,the synthesized PtNi electrocatalysts demonstrate outstanding catalytic activity and long-term stability for HER,achieving low overpotentials of 19 and 203 mV at current densities of 10 and 1000 mA/cm^(2),respectively.The superior performance can be attributed to the combination of a refined particle size,lattice strains,and synergistic effects between Pt and Ni.This rapid liquid-state synthesis demonstrated here holds great potential for scalable and industrial manufacturing of micro-/nano-catalysts. 展开更多
关键词 Hydrogen evolution reaction High-temperature liquid shock Pt-based nanocatalysts Rapid synthesis ELECTROCATALYST
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Precise synthesis of ortho-deuterated aromatic derivatives:An arylthianthrenium salt-based platform approach
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作者 Yunhao Guan Xia Peng +3 位作者 Rong Fan Xiaoying Feng Hongguang Du Jiajing Tan 《Chinese Chemical Letters》 2026年第1期259-265,共7页
The deuterium labeling has garnered significant interest in drug discovery due to its critical role on improving pharmacokinetic and metabolic properties.However,despite its pharmaceutical value,the general and rapid ... The deuterium labeling has garnered significant interest in drug discovery due to its critical role on improving pharmacokinetic and metabolic properties.However,despite its pharmaceutical value,the general and rapid syntheses of aromatic scaffolds that contains deuterium remain an important yet elusive task.State-of-the-art approaches mainly relied on the transition metal-catalyzed C-H deuteration via the assistance of directing groups(DGs),which often suffered from over-deuteration and lengthy step counts required for installation and/or removal of DG.Herein,we report a generalizable synthetic linchpin strategy for the facile preparation of the ortho-deuterated aromatic core.Through capture of aryne-derived 1,3-zwitterion with heavy water,we synthesized an array of ortho-deuterated aryl sulfonium salts.These novel linchpins not only participated the transition metal catalyzed cross-coupling reaction as nucleophiles,but also served as aryl radical reservoirs under photochemical or electrochemical conditions,enabling facile and precise access to structurally diverse deuterated aromatics.Moreover,we have disclosed a novel EDA complex enabled direct arylation of phosphines under visible-light irradiation,further expanding the utility of our platform approach. 展开更多
关键词 Deuterium labeling Thianthrenium salts Precise synthesis Linchpin strategy Aryne chemistry Organosulfur chemistry
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In-situ synthesis of rare earth Y-type zeolite enhanced by high-gravity technology
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作者 Lang Xu Wenhui Hou +3 位作者 Houmei You Baochang Sun Guangwen Chu Jianfeng Chen 《Chinese Journal of Chemical Engineering》 2026年第1期240-248,共9页
Rare earth(RE)Y-type zeolite was synthesized in situ by acidic co-hydrolysis route and hydrothermal method.The key process parameters were optimized based on the RE utilization rate.The effect of inducing a rotating p... Rare earth(RE)Y-type zeolite was synthesized in situ by acidic co-hydrolysis route and hydrothermal method.The key process parameters were optimized based on the RE utilization rate.The effect of inducing a rotating packed bed(RPB)in premixing and crystallization on crystallinity and RE utilization rate was further investigated.The results indicate that lanthanide(La)cations are successfully introduced into the sodalite cage of Y-type zeolite.The optimized conditions are that the molar ratio of Si/La is 150,premixing for 5 h,crystallization at 90℃ for 18 h,and calcination at 550℃ for 3.5 h.At this stage,the RE utilization rate reaches 74.5%.Compared with the conventional stirred tank reactor(STR),RPB can effectively shorten the premixing time and crystallization time by 4.3 h and 6 h,improve the crystallinity by 23%and RE utilization rate by 7.5%.The RE utilization rate is more than 80%by RPB,surpassing the effectiveness of using the one-exchange one-calcination process in the traditional liquid ion exchange process.It is expected to provide a reference for the in-situ efficient and green synthesis of RE zeolite. 展开更多
关键词 High-gravity technology Rare earth zeolite In-situ synthesis Rare earth utilization rate
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Effects of changing assimilate supply on starch synthesis in maize kernels under high temperature stress
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作者 Teng Li Shumei Wang +5 位作者 Qing Liu Xuepeng Zhang Lin Chen Yuanquan Chen Wangsheng Gao Peng Sui 《Journal of Integrative Agriculture》 2026年第2期639-647,共9页
High temperature stress (HT) significantly reduces maize yield by impairing starch accumulation in kernels.However,the mechanism by which HT affects starch synthesis remains controversial-whether through reduced assim... High temperature stress (HT) significantly reduces maize yield by impairing starch accumulation in kernels.However,the mechanism by which HT affects starch synthesis remains controversial-whether through reduced assimilate supply or direct inhibition on kernel metabolism.To clarify these mechanisms,a heat-sensitive maize hybrid,Xianyu 335 (XY),was exposed to 30℃/20℃ (maximum/minimum temperature,control) and 40℃/30℃ for seven consecutive days during the seed setting stage.Synchronous pollination (SP),apical pollination (AP),and shading treatments were applied to manipulate the inherent source–sink ratio in maize plants.Results showed that apical kernel weight decreased by 11.9%under 40℃ in the SP treatment.The ^(13)C content,starch accumulation,and cell-wall invertase (CWIN) activity also declined by 15.9,36.7,and 16.4%,respectively,under HT.In the shading treatment,40℃/30℃ caused even greater reductions in^(13)C content,starch accumulation,and CWIN activity due to diminished assimilate supply.Conversely,in the AP treatment,starch content and CWIN activity increased by 22.0 and 18.5%,respectively,under 40℃/30℃,resulting in kernel weight and ^(13)C content similar to those in SP and shading treatments regardless of temperature.Consistent with apical kernels under AP,HT did not negatively affect middle kernels in either SP or shading treatments,as kernel weight and starch content remained unchanged under HT.Although all kernels were exposed to the same HT or control environment,their responses varied a lot.The impaired starch synthesis in apical kernels under HT was rescued by increasing carbon supply via AP treatment.The contrasting performance among middle kernels,apical kernels under AP,and apical kernels under SP or shading indicates that reduced carbon supply is a critical factor underlying inhibited starch accumulation.Our findings provide a theoretical basis for further understanding kernel abortion under HT. 展开更多
关键词 high temperature stress MAIZE seed setting stage cell wall invertase starch synthesis
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On-site electrocatalytic synthesis of hydrogen peroxide in potassium fertilizer solutions
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作者 Kaijie Wu Xinxin Li +4 位作者 Sheng Chen Qi Huang Xue-Quan Zhou Jinhui Liu Cheng Tang 《Journal of Energy Chemistry》 2026年第2期22-28,I0003,共8页
The two-electron electrochemical oxygen reduction reaction(ORR)affords an appealing alternative for on-site production of hydrogen peroxide(H_(2)O_(2)),which can fulfill the demands of various applications even at low... The two-electron electrochemical oxygen reduction reaction(ORR)affords an appealing alternative for on-site production of hydrogen peroxide(H_(2)O_(2)),which can fulfill the demands of various applications even at low concentrations.Under neutral or near-neutral conditions,the electrolyte environment capable of electrochemically synthesizing H_(2)O_(2) exhibits diversity and holds vast potential for practical applications;however,the electrocatalytic performance is limited without desirable electrode materials.In this contribution,methoxylated nickel hydroxides were proposed for high-performance on-site H_(2)O_(2) electrosynthesis in different potassium fertilizer solutions.The methoxylation compared to pristine Ni(OH)_(2) was demonstrated to optimize the electronic structure with favorable adsorption of reaction intermediates,obviously enhancing the activity and selectivity.In 0.10 M K_(2)SO_(4) solution,H_(2)O_(2) production ranged from 28.1 to 153.6 mg h^(-1) cm^(-2) at current densities of-50 to-250 mA cm^(-2),accompanied by Faradaic efficiency values exceeding 88.0%.An integrated system was devised by combining fertilization,disinfection,and irrigation through the coupling of two-electron ORR with agricultural irrigation,utilizing nutrient solutions as the electrolyte for on-site H_(2)O_(2) electrosynthesis.These findings afford a promising avenue for the practical application of 2e-ORR in neutral environments. 展开更多
关键词 Oxygen reduction reaction Hydrogen peroxide On-site electrocatalytic synthesis Agricultural irrigation Energy electrocatalysis
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