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Identification of two novel sesterterpene skeletons offers the first experimental evidence for the cyclization mechanism of mangicdiene synthase
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作者 Pan Luo Jian-Ming Lv +9 位作者 Hong-Ting Zhen Ying-Qi Zhao Jing-Yuan Liu Jin-Yu Hong Shao-Yang Li Gao-Qian Wang Guo-Dong Chen Shui-Xing Zhang Dan Hu Hao Gao 《Chinese Chemical Letters》 2026年第1期399-403,共5页
Mangicol-type sesterterpenoids possess potent anti-inflammatory activity,characterized by a 5-5-6-5tetracyclic carbon skeleton formed by mangicdiene synthase Fg MS.Two proposed mechanisms for mangicdiene formation inv... Mangicol-type sesterterpenoids possess potent anti-inflammatory activity,characterized by a 5-5-6-5tetracyclic carbon skeleton formed by mangicdiene synthase Fg MS.Two proposed mechanisms for mangicdiene formation involve either C6-C10 cyclization(path a) or C2-C10 cyclization(path b) after the C10carbocation formation,but neither has been experimentally validated.Here,we have identified a second mangicdiene synthase Man D,which is derived from Fusarium sp.JNU-XJ070152-01 and shares high amino acid sequence identity with Fg MS.Through heterologous expression of man D in Aspergillus oryzae NSAR1,we observed production not only of mangicdiene(1) and variecoltetraene(2),previously identified by expression of Fg MS in Escherichia coli,but also two novel sesterterpene skeletons fusadiene(3)and fusatriene(4).The identification of fusadiene and fusatriene supports the occurrence of two key carbocation intermediates in path b,thus experimentally confirming that mangicdiene is built via path b for the first time,consistent with previous density functional theory(DFT) calculation results. 展开更多
关键词 Mangicol-type sesterterpenoid Terpene cyclase Heterologous expression Aspergillus oryzae cyclization mechanism
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From Biomass to Chiral Chemicals via Chemocatalysis:Advances and Prospects
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作者 Shuguang Xu Shengqi Liao +1 位作者 Jianmei Li Changwei Hu 《Chinese Journal of Chemical Physics》 2026年第1期73-88,I0043,共17页
Optically pure chiral chemicals are important building blocks with widespread applications across mul-tiple scientific and industrial do-mains such as in pharmaceuticals,agrochemicals,and food,especially acting as pre... Optically pure chiral chemicals are important building blocks with widespread applications across mul-tiple scientific and industrial do-mains such as in pharmaceuticals,agrochemicals,and food,especially acting as precursors to synthesize biodegradable polymers.As an al-ternative to fossil resources,renew-able lignocellulosic biomass has been used to access chiral chemicals,due to the versatile inherent stere-ostructures and multiple functional groups,such as hydroxyl,carbonyl,and phenyl ether groups.Typically,as the two main units of(hemi)cel-lulose components in lignocellulosic biomass,D-xylose and D-glucose bear multiple chiral centers(e.g.,2R-3S-4R for D-xylose and 2R-3S-4R-5R for D-glucose).Lignin bearsβ-O-4 linkages,exhibiting(R,S/S,R)or(R,R/S,S)stereocenters at the side-chainαandβcarbon atoms.The valorization of biomass into optical-ly pure chiral chemicals is vital for developing a more sustainable future.This review discuss-es the production of typical chiral chemicals derived from biomass through chemocatalysis,including lactones(e.g.,R/S-valerolactone),carboxylic acids(e.g.,D/L-glyceric acid,D/L-lactic acid),polyols(e.g.,tetrose),furans,oligosaccharides,and others.Two strategies are generally employed.One approach involves first producing achiral platform chemicals from biomass,followed by the introduction of asymmetric catalysts to reconstruct stereocenters.The second relates to selectively preserving one or more inherent stereocenters in the natural biomass structure during complex cascade reactions in which biomass feedstock acts as a“chi-ral pool",thus eliminating the establishment of stereocenter.The feedstock,methods em-ployed,and enantioselectivity and applications of the target chiral chemicals are discussed.Despite these advances,the synthesis of optically pure chemicals from biomass is still in its in-fancy.The coming decade presents both extraordinary challenges and opportunities in biomass-derived chiral chemistry.Future research should be focused on:(1)integrating well-established asymmetric catalysis techniques and methods with biomass’s inherent chiral pools,presenting an unprecedented opportunity to expand the chemical space of sustainable chiral compounds;(2)mastering polyfunctional complexity of chiral chemicals through holis-tic utilization of biomass’multichiral centers;(3)unlocking lignin’s stereochemical treasury that represents the next frontier in biomass valorization. 展开更多
关键词 Biomass valorization Carbohydrates LIGNIN Chiral chemicals Enantioselectiv-ity
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Chemically Engineered Hydroxyl-terminated Polybutadiene Yields Stable and High-strain Intrinsically Conductive Polyurethane Piezoresistive Sensors
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作者 Li Zhou Guo-Xuan Ma +6 位作者 Wen-Xue Tian Wen-Cong Sun Shu-Miao Li Xiao-Ru Wang Wen-Chao Ji Yin-Yong Sun Chun-Xiang Li 《Chinese Journal of Polymer Science》 2026年第1期100-115,I0011,共17页
The development of intrinsically conductive piezoresistive sensors with high strain tolerance has garnered significant interest.While elastomeric polymers exhibit excellent strain capabilities,their utility in sensing... The development of intrinsically conductive piezoresistive sensors with high strain tolerance has garnered significant interest.While elastomeric polymers exhibit excellent strain capabilities,their utility in sensing applications has been limited by inherent challenges such as high electrical resistivity,poor aging resistance,and interfacial incompatibility.To address these limitations,hydroxyl-terminated polybutadiene(HTPB)-based polyurethane was chemically modified with acetylferrocene-polyaniline conductive moieties to enhance charge transport properties.Remarkably,this covalent functionalization endowed the resulting ferrocene-polyaniline hybrid polyurethane(FPHP)with a conductivity of2.33 n A at 1 V bias while preserving piezoresistive functionality.The FPHP demonstrated exceptional mechanical-electrical performance,achieving 254% elongation at break with strain-dependent gauge factors of 7.28(0%-12.5% strain,R^(2)=0.9504)and 19.66(12.5%-35.0% strain,R^(2)=0.9929).Further characterization revealed a rapid 0.60 s response time and stability over 3500 strain-release cycles at compression strain,underscoring its durability under repetitive loading.The FPHP sensor was capable of monitoring various human movements and recognizing writing signals.These advances establish a materials design paradigm for fabricating flexible sensors that synergistically integrate high deformability,tunable sensitivity,and robust operational stability,positioning FPHP as a promising candidate for next-generation wearable electronics and soft robotics. 展开更多
关键词 Piezoresistive sensor chemical modification Intrinsically conducting polyurethane Hydroxyl-terminated polybutadiene
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Retaining local chemical effects:An error cancellation strategy for calculating standard gas-phase enthalpy of formation
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作者 Rui Liu Chaoyang Zhang +2 位作者 Linyuan Wang Zhiyu Huang Jian Liu 《Defence Technology(防务技术)》 2026年第1期172-179,共8页
Conventional error cancellation approaches separate molecules into smaller fragments and sum the errors of all fragments to counteract the overall computational error of the parent molecules.However,these approaches m... Conventional error cancellation approaches separate molecules into smaller fragments and sum the errors of all fragments to counteract the overall computational error of the parent molecules.However,these approaches may be ineffective for systems with strong localized chemical effects,as fragmenting specific substructures into simpler chemical bonds can introduce additional errors instead of mitigating them.To address this issue,we propose the Substructure-Preserved Connection-Based Hierarchy(SCBH),a method that automatically identifies and freezes substructures with significant local chemical effects prior to molecular fragmentation.The SCBH is validated by the gas-phase enthalpy of formation calculation of CHNO molecules.Therein,based on the atomization scheme,the reference and test values are derived at the levels of Gaussian-4(G4)and M062X/6-31+G(2df,p),respectively.Compared to commonly used approaches,SCBH reduces the average computational error by half and requires only15%of the computational cost of G4 to achieve comparable accuracy.Since different types of local effect structures have differentiated influences on gas-phase enthalpy of formation,substituents with strong electronic effects should be retained preferentially.SCBH can be readily extended to diverse classes of organic compounds.Its workflow and source code allow flexible customization of molecular moieties,including azide,carboxyl,trinitromethyl,phenyl,and others.This strategy facilitates accurate,rapid,and automated computations and corrections,making it well-suited for high-throughput molecular screening and dataset construction for gas-phase enthalpy of formation. 展开更多
关键词 Gas-phase enthalpy of formation Error cancellation Quantum chemical High throughput
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Emerging Chemical and Biological Materials Technologies in the Extraplanetary Environment
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作者 Qingyao Jiang Bin Wang +3 位作者 Yifan Cheng Yiming Wang Hongxin Zhao Yuan Lu 《Nano-Micro Letters》 2026年第5期235-298,共64页
Space exploration and manufacturing are of critical importance for scientific advancement,technological innovation,national security,and the acquisition of extraterrestrial resources.In view of this,chemical and biolo... Space exploration and manufacturing are of critical importance for scientific advancement,technological innovation,national security,and the acquisition of extraterrestrial resources.In view of this,chemical and biological nano-/micro-/meso-scale manufacturing provide complementary approaches to overcome key space exploration challenges by enabling the in-situ production of essential life-support materials,propellants,and other resources.This review examines the origin and historical evolution of space manufacturing and the latest advances across different environments—from orbital space stations and the lunar surface to Mars and asteroids.It is structured to present the current state of research,outline key manufacturing strategies and technologies,assess the technical and environmental challenges,and discuss emerging trends and future directions.Besides,the potential applications of emerging technologies such as synthetic biology and artificial intelligence in overcoming the limitations of microgravity,limited resources,and extreme conditions are discussed.Ultimately,this integrative review could serve to guide future development,from advancing space science and disruptive manufacturing to enabling interdisciplinary and application-level innovations. 展开更多
关键词 In-space manufacturing Biomanufacturing chemical manufacturing Long-term space mission In-situ resource utilization
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Thermal decomposition and kinetics of diisopropyl methylphosphonate(DIMP),a chemical warfare agent simulant
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作者 Natalie Gese Hergen Eilers 《Defence Technology(防务技术)》 2026年第1期40-51,共12页
Chemical warfare agents(CWAs)remain a persistent hazard in many parts of the world,necessitating a deeper exploration of their chemical and physical characteristics and reactions under diverse conditions.Diisopropyl m... Chemical warfare agents(CWAs)remain a persistent hazard in many parts of the world,necessitating a deeper exploration of their chemical and physical characteristics and reactions under diverse conditions.Diisopropyl methylphosphonate(DIMP),a commonly used CWA surrogate,is widely studied to enhance our understanding of CWA behavior.The prevailing thermal decomposition model for DIMP,developed approximately 25 years ago,is based on data collected in nitrogen atmospheres at temperatures ranging from 700 K to 800 K.Despite its limitations,this model continues to serve as a foundation for research across various thermal and reactive environments,including combustion studies.Our recent experiments have extended the scope of decomposition analysis by examining DIMP in both nitrogen and zero air across a lower temperature range of 175℃ to 250℃.Infrared spectroscopy results under nitrogen align well with the established model;however,we observed that catalytic effects,stemming from decomposition byproducts and interactions with stainless steel surfaces,alter the reaction kinetics.In zero air environments,we observed a novel infrared absorption band.Spectral fitting suggests this band may represent a combination of propanal and acetone,while GCMS analysis points to vinyl formate and acetone as possible constituents.Although the precise identity of these new products remains unresolved,our findings clearly indicate that the existing decomposition model cannot be reliably extended to lower temperatures or non-nitrogen environments without further revisions. 展开更多
关键词 chemical warfare agents Simulants Diisopropyl methylphosphonate Thermal decomposition Decomposition model PROPANAL Vinyl formate ACETONE
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Remediation of characteristic contaminants in groundwater of chemical industrial by the activation of PMS:Recent developments and challenges-a mini-review
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作者 Yingnan Duan Jinyu Liu +3 位作者 Qian Liu Tianhao Li Hexiang Zhao Zhurui Shen 《Chinese Chemical Letters》 2026年第1期177-185,共9页
Groundwater is a key part of the terrestrial ecosystem,but it is vulnerable to pollution in the context of chemical industry development.Treating contaminated groundwater is challenging due to its stable water quality... Groundwater is a key part of the terrestrial ecosystem,but it is vulnerable to pollution in the context of chemical industry development.Treating contaminated groundwater is challenging due to its stable water quality,hidden contamination,and complex treatment requirements.Current research focuses on advanced treatment technologies,among which the advanced oxidation process(AOPs) of peroxomonosulfate(PMS) has great potential.Although there are many reviews of PMS-based AOP,most of them focus on surface water.This review aims to explore the activation reaction of PMS to groundwater by in-situ chemical oxidation(ISCO) technology,further study the reaction mechanism,compare the treatment effect of characteristic pollutants in the groundwater of the chemical industry park,propose new activation methods and catalyst selection,and provide guidance for future groundwater treatment research. 展开更多
关键词 Advanced oxidation processes(AOPs) In-situ chemical oxidation PMS Groundwater contamination Characteristic pollutants
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Lithium Nitrate Effects for Lithium-Based Chemical Batteries:A Review
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作者 Xianshu Wang Junru Wu +6 位作者 Huirong Wang Xiangshao Yin Zhuo Zhou Yuanyuan Huang Yelong Zhang Weishan Li Baohua Li 《Carbon Energy》 2026年第1期197-222,共26页
Lithium metal batteries(LMBs)have been regarded as one of the most promising alternatives in the post-lithium battery era due to their high energy density,which meets the needs of light-weight electronic devices and l... Lithium metal batteries(LMBs)have been regarded as one of the most promising alternatives in the post-lithium battery era due to their high energy density,which meets the needs of light-weight electronic devices and long-range electric vehicles.However,technical barriers such as dendrite growth and poor Li plating/stripping reversibility severely hinder the practical application of LMBs.However,lithium nitrate(LiNO_(3))is found to be able to stabilize the Li/electrolyte interface and has been used to address the above challenges.To date,considerable research efforts have been devoted toward understanding the roles of LiNO_(3) in regulating the surface properties of Li anodes and toward the development of many effective strategies.These research efforts are partially mentioned in some articles on LMBs and yet have not been reviewed systematically.To fill this gap,we discuss the recent advances in fundamental and technological research on LiNO_(3) and its derivatives for improving the performances of LMBs,particularly for Li-sulfur(S),Li-oxygen(O),and Li-Li-containing transition-metal oxide(LTMO)batteries,as well as LiNO_(3)-containing recipes for precursors in battery materials and interphase fabrication.This review pays attention to the effects of LiNO_(3) in lithium-based batteries,aiming to provide scientific guidance for the optimization of electrode/electrolyte interfaces and enrich the design of advanced LMBs. 展开更多
关键词 effects and mechanisms LiNO_(3)derivatives LiNO_(3)-containing recipes lithium metal anode Lithium nitrate basis lithium-based chemical batteries
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Chemical exchange saturation transfer MRI for neurodegenerative diseases:An update on clinical and preclinical studies
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作者 Ahelijiang Saiyisan Shihao Zeng +4 位作者 Huabin Zhang Ziyan Wang Jiawen Wang Pei Cai Jianpan Huang 《Neural Regeneration Research》 2026年第2期553-568,共16页
Chemical exchange saturation transfer magnetic resonance imaging is an advanced imaging technique that enables the detection of compounds at low concentrations with high sensitivity and spatial resolution and has been... Chemical exchange saturation transfer magnetic resonance imaging is an advanced imaging technique that enables the detection of compounds at low concentrations with high sensitivity and spatial resolution and has been extensively studied for diagnosing malignancy and stroke.In recent years,the emerging exploration of chemical exchange saturation transfer magnetic resonance imaging for detecting pathological changes in neurodegenerative diseases has opened up new possibilities for early detection and repetitive scans without ionizing radiation.This review serves as an overview of chemical exchange saturation transfer magnetic resonance imaging with detailed information on contrast mechanisms and processing methods and summarizes recent developments in both clinical and preclinical studies of chemical exchange saturation transfer magnetic resonance imaging for Alzheimer’s disease,Parkinson’s disease,multiple sclerosis,and Huntington’s disease.A comprehensive literature search was conducted using databases such as PubMed and Google Scholar,focusing on peer-reviewed articles from the past 15 years relevant to clinical and preclinical applications.The findings suggest that chemical exchange saturation transfer magnetic resonance imaging has the potential to detect molecular changes and altered metabolism,which may aid in early diagnosis and assessment of the severity of neurodegenerative diseases.Although promising results have been observed in selected clinical and preclinical trials,further validations are needed to evaluate their clinical value.When combined with other imaging modalities and advanced analytical methods,chemical exchange saturation transfer magnetic resonance imaging shows potential as an in vivo biomarker,enhancing the understanding of neuropathological mechanisms in neurodegenerative diseases. 展开更多
关键词 Alzheimer’s disease chemical exchange saturation transfer Huntington’s disease magnetic resonance imaging molecular imaging multiple sclerosis neurodegenerative disease Parkinson’s disease
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Catalyst-free,direct electrochemical trifluoromethylation/cyclization of N-arylacrylamides using TfNHNHBoc as a CF_(3) source 被引量:2
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作者 Han Wang Yongbin Xie +2 位作者 Yicheng Zhou Nannan Cen Wenbo Chen 《Chinese Chemical Letters》 SCIE CAS CSCD 2022年第1期221-224,共4页
A new electrochemical strategy for trifluoromethylation/cyclization using TfNHNHBoc as a CF_(3)source was established.This approach was realized by the direct electrolysis of Tf NHNHBoc under external oxidantfree and ... A new electrochemical strategy for trifluoromethylation/cyclization using TfNHNHBoc as a CF_(3)source was established.This approach was realized by the direct electrolysis of Tf NHNHBoc under external oxidantfree and catalyst-free conditions,and afforded various trifluoromethylated oxindoles with good functional group compatibility and broad substrate scope.Preliminary mechanistic studies show that the reaction proceeds by a radical process. 展开更多
关键词 ELECTROLYSIS TRIFLUOROMETHYLATION cyclization TfNHNHBoc Radical process
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Regioselective electrochemical oxidative radical ortho‐(4+2)/ipso‐(3+2)cyclization 被引量:1
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作者 Zhipeng Guan Dongfeng Yang +7 位作者 Zhao Liu Shuxiang Zhu Xingxing Zhong Huamin Wang Xiangwei Li Xiaotian Qi Hong Yi Aiwen Lei 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 2023年第9期144-153,共10页
Achieving regioselectivity in radical cyclization reactions is of central importance,yet extremely challenging.Although Baldwin’s rules provided guidance on the addition of radical species with alkenes/alkynes,the or... Achieving regioselectivity in radical cyclization reactions is of central importance,yet extremely challenging.Although Baldwin’s rules provided guidance on the addition of radical species with alkenes/alkynes,the ortho-/ipso-selectivity of the cyclic reaction between radical species(especially alkyl and alkenyl radical)and aryl groups is still ambiguous.Herein,we develop an electrochemically enabled regioselective ortho-(4+2)/ipso-(3+2)cyclization of alkyl/alkenyl radicals with aryl groups,which provides a series of tetrahydronaphthalene and spirocarbocycle derivatives,exhibiting a broad substrate scope and functional group tolerance.Alkyl/alkenyl radicals are generated by Cp2Fe-mediated electrochemical oxidative radical addition of benzylic malonates with alkenes and alkynes.The method avoids the use of chemical oxidant/base/noble metal,the pre-functionalization of substrates,and the over-oxidation of compounds.Theoretical studies reveal that the dominant factor promoting the alkene-preferred ortho-addition is the favorable interaction energy;the alkyne-preferred ipso-addition regioselectivity is controlled by the distortion energy.Notably,this strategy is regarded as an important supplement to Baldwin’s rules for radical cyclization. 展开更多
关键词 Regioselectivity RADICAL Ortho-(4+2)/ipso-(3+2)cyclization Electrochemical oxidation Carbocyclic compound
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The autophagy-lysosome pathway:a potential target in the chemical and gene therapeutic strategies for Parkinson’s disease 被引量:3
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作者 Fengjuan Jiao Lingyan Meng +1 位作者 Kang Du Xuezhi Li 《Neural Regeneration Research》 SCIE CAS 2025年第1期139-158,共20页
Parkinson’s disease is a common neurodegenerative disease with movement disorders associated with the intracytoplasmic deposition of aggregate proteins such asα-synuclein in neurons.As one of the major intracellular... Parkinson’s disease is a common neurodegenerative disease with movement disorders associated with the intracytoplasmic deposition of aggregate proteins such asα-synuclein in neurons.As one of the major intracellular degradation pathways,the autophagy-lysosome pathway plays an important role in eliminating these proteins.Accumulating evidence has shown that upregulation of the autophagy-lysosome pathway may contribute to the clearance ofα-synuclein aggregates and protect against degeneration of dopaminergic neurons in Parkinson’s disease.Moreover,multiple genes associated with the pathogenesis of Parkinson’s disease are intimately linked to alterations in the autophagy-lysosome pathway.Thus,this pathway appears to be a promising therapeutic target for treatment of Parkinson’s disease.In this review,we briefly introduce the machinery of autophagy.Then,we provide a description of the effects of Parkinson’s disease–related genes on the autophagy-lysosome pathway.Finally,we highlight the potential chemical and genetic therapeutic strategies targeting the autophagy–lysosome pathway and their applications in Parkinson’s disease. 展开更多
关键词 AUTOPHAGY chemical therapy gene therapy Parkinson’s disease Α-SYNUCLEIN
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Chemical composition and biological activities of Angelica sinensis 被引量:2
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作者 Jiankun Jin Zixuan Che +4 位作者 Rui Liu Ruiqi Ma Ying Li Meng Zhang Yu Chen 《Asian Journal of Traditional Medicines》 2025年第6期285-296,共12页
Angelica sinensis(A.sinensis),as a kind of Chinese medicine,has the effects of tonifying blood,promoting blood circulation,regulating menstrual flow,relieving pain,moistening bowel and so on.By consulting Sciencedirec... Angelica sinensis(A.sinensis),as a kind of Chinese medicine,has the effects of tonifying blood,promoting blood circulation,regulating menstrual flow,relieving pain,moistening bowel and so on.By consulting Sciencedirect database and Web of Science database,163 related articles were found,of which 36 were related to chemical composition and pharmacological activities of A.sinensis.In this paper,the chemical structures and different derivatives were systematically summarized by reviewing relevant literatures,and the pharmacological effects were also summarized. 展开更多
关键词 Angelica sinensis chemical composition biological activity
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Research Progress on Chemical Constituents and Pharmacological Effects of Zexie(Alismatis Rhizoma) 被引量:1
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作者 Wanbing Shang Bian Wang +1 位作者 Haoyue Yuan Linlin Li 《Chinese Medicine and Natural Products》 2025年第4期213-225,共13页
As a diuretic and dampness-eliminating medicinal agent in traditional Chinese medicine(TCM),Zexie(Alismatis Rhizoma)is commonly used for symptoms such as dysuria,edema and abdominal distension,diarrhea with oliguria,a... As a diuretic and dampness-eliminating medicinal agent in traditional Chinese medicine(TCM),Zexie(Alismatis Rhizoma)is commonly used for symptoms such as dysuria,edema and abdominal distension,diarrhea with oliguria,and dizziness due to phlegm–fluid retention.Systematic phytochemical studies have revealed that the active components of Zexie(Alismatis Rhizoma)are primarily triterpenoids,along with sesquiterpenes,polysaccharides,sterols,alkaloids,phenolic acids,and lignans.These components form the material basis for its pharmacological activities.Recent breakthroughs in pharmacological research have expanded beyond its traditionally recognized diuretic and anti-inflammatory effects:Its antiurolithiasis effect has been clearly linked to inhibiting the crystallization of stone components and promoting stone expulsion;its renal protective effect can ameliorate kidney injury by reducing oxidative stress and suppressing inflammatory responses in renal tissues;its lipid-lowering mechanism involves regulating lipid metabolism pathways and reducing lipid deposition;in terms of anticancer activity,it exhibits proliferation inhibition and apoptosis induction in various tumor cells such as liver,lung,and colon cancers;additionally,it shows significant antibacterial activity against pathogens,including Escherichia coli and Staphylococcus aureus. 展开更多
关键词 Alismatis Rhizoma Zexie chemical constituents pharmacological effects REVIEW
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Farmers,Chemicals and Fertility of Soil:A Quest to Sustainability 被引量:1
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作者 Srinivas Katherasala Ram Shepherd Bheenaveni +1 位作者 Surender Thaduru Thirupathi Deekonda 《Journal of Environmental & Earth Sciences》 2025年第3期58-76,共19页
This study examines the evolving use of synthetic chemicals in intensive agriculture over the past decade.It highlights the negative impacts of chemical inputs on soil health and ecosystem integrity and recommends kno... This study examines the evolving use of synthetic chemicals in intensive agriculture over the past decade.It highlights the negative impacts of chemical inputs on soil health and ecosystem integrity and recommends knowledge-sharing platforms,soil protection laws,and collaborative efforts between regulatory agencies and agricultural experts.The study emphasizes the need for a balanced approach that includes natural methods alongside synthetic chemicals,particularly herbicides.Ten years ago,farmers primarily used urea,DAP,and potassium for nutrients.However,increased awareness,market forces,and government subsidies have led to a significant rise in herbicide use as a cost-effective weed management strategy.Over the past decade,synthetic fertilizer use for cotton cultivation has increased by 80%,leading to deteriorating soil quality.Paddy cultivation has decreased by 23%,while cotton cultivation has increased by 20.4%due to higher economic incentives.Currently,89.1%of farmers use herbicides,compared to 97.2%who did not a decade ago.Insecticide use has also surged,with 97.8%of farmers applying 1.5 liters or more per acre.The excessive use of chemicals threatens soil fertility and disrupts the ecosystem’s balance.This article explores the reasons behind the adoption of chemical-intensive farming practices and offers insights into farmers’decision-making processes.The careful use of synthetic chemicals is essential to safeguard soil health and maintain ecological balance. 展开更多
关键词 Ecosystem Integrity HERBICIDES Intensive Agriculture Soil Health Synthetic chemicals
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Diffusion-based generative drug-like molecular editing with chemical natural language 被引量:1
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作者 Jianmin Wang Peng Zhou +6 位作者 Zixu Wang Wei Long Yangyang Chen Kyoung Tai No Dongsheng Ouyang Jiashun Mao Xiangxiang Zeng 《Journal of Pharmaceutical Analysis》 2025年第6期1215-1225,共11页
Recently,diffusion models have emerged as a promising paradigm for molecular design and optimization.However,most diffusion-based molecular generative models focus on modeling 2D graphs or 3D geom-etries,with limited ... Recently,diffusion models have emerged as a promising paradigm for molecular design and optimization.However,most diffusion-based molecular generative models focus on modeling 2D graphs or 3D geom-etries,with limited research on molecular sequence diffusion models.The International Union of Pure and Applied Chemistry(IUPAC)names are more akin to chemical natural language than the simplified molecular input line entry system(SMILES)for organic compounds.In this work,we apply an IUPAC-guided conditional diffusion model to facilitate molecular editing from chemical natural language to chemical language(SMILES)and explore whether the pre-trained generative performance of diffusion models can be transferred to chemical natural language.We propose DiffIUPAC,a controllable molecular editing diffusion model that converts IUPAC names to SMILES strings.Evaluation results demonstrate that our model out-performs existing methods and successfully captures the semantic rules of both chemical languages.Chemical space and scaffold analysis show that the model can generate similar compounds with diverse scaffolds within the specified constraints.Additionally,to illustrate the model’s applicability in drug design,we conducted case studies in functional group editing,analogue design and linker design. 展开更多
关键词 Diffusion model IUPAC Molecular generative model chemical natural language Transformer
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Photoinduced Difluoromethylation/Cyclization of 2-Aryl Indoles with HCF_(2)SO_(2)Na
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作者 Jiang Jie Li Jiali +3 位作者 Pan Ruohan Chen Yu Liu Jiale Tang Yucai 《有机化学》 北大核心 2025年第4期1239-1248,共10页
Difluoromethyl compounds are widely found in natural products,bioactive molecule and pharmaceuticals.A visible-light induced difluoromethylation/cyclization of 2-aryl indoles is described to construct indolo[2,1-a]iso... Difluoromethyl compounds are widely found in natural products,bioactive molecule and pharmaceuticals.A visible-light induced difluoromethylation/cyclization of 2-aryl indoles is described to construct indolo[2,1-a]isoquinolin-6(5H)-one derivatives using the inexpensive and easy-to-handle HCF_(2)SO_(2)Na as an HCF2 sources.Diverse difluoromethylated indolo[2,1-a]isoquinolines were readily obtained in moderate to good yields.Mechanistic studies demonstrate that the reaction may involve a radical process. 展开更多
关键词 difluoromethyl compounds visible-light 2-aryl indoles difluoromethylation/cyclization
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Structure factors dictate the ionic conductivity and chemical stability for cubic garnet-based solid-state electrolyte 被引量:1
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作者 Jingyu Shi Xiaofeng Wu +7 位作者 Yutong Chen Yi Zhang Xiangyan Hou Ruike Lv Junwei Liu Mengpei Jiang Keke Huang Shouhua Feng 《Chinese Chemical Letters》 2025年第5期198-210,共13页
Solid-state electrolytes(SSEs),as the core component within the next generation of key energy storage technologies-solid-state lithium batteries(SSLBs)-are significantly leading the development of future energy storag... Solid-state electrolytes(SSEs),as the core component within the next generation of key energy storage technologies-solid-state lithium batteries(SSLBs)-are significantly leading the development of future energy storage systems.Among the numerous types of SSEs,inorganic oxide garnet-structured superionic conductors Li7La3Zr2O12(LLZO)crystallized with the cubic Iaˉ3d space group have received considerable attention owing to their highly advantageous intrinsic properties encompassing reasonable lithium-ion conductivity,wide electrochemical voltage window,high shear modulus,and excellent chemical stability with electrodes.However,no SSEs possess all the properties necessary for SSLBs,thus both the ionic conductivity at room temperature and stability in ambient air regarding cubic garnet-based electrolytes are still subject to further improvement.Hence,this review comprehensively covers the nine key structural factors affecting the ion conductivity of garnet-based electrolytes comprising Li concentration,Li vacancy concentration,Li carrier concentration and mobility,Li occupancy at available sites,lattice constant,triangle bottleneck size,oxygen vacancy defects,and Li-O bonding interactions.Furthermore,the general illustration of structures and fundamental features being crucial to chemical stability is examined,including Li concentration,Li-site occupation behavior,and Li-O bonding interactions.Insights into the composition-structure-property relations among cubic garnet-based oxide ionic conductors from the perspective of their crystal structures,revealing the potential compatibility conflicts between ionic transportation and chemical stability resulting from Li-O bonding interactions.We believe that this review will lay the foundation for future reasonable structural design of oxide-based or even other types of superionic conductors,thus assisting in promoting the rapid development of alternative green and sustainable technologies. 展开更多
关键词 Garnet-structured solid-state electrolyte Structure factors Ionic conductivity chemical stability Li-ion battery
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Achievable dual-strategy to stabilize Li-rich layered oxide interface by a one-step wet chemical reaction towards long oxygen redox reversibility 被引量:2
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作者 Bin He Yujie Dai +7 位作者 Shuai Jiang Dawei Chen Xilong Wang Jie Song Dan Xiao Qian Zhao Yan Meng Wei Feng 《Journal of Energy Chemistry》 2025年第2期120-131,I0004,共13页
Oxygen release and electrolyte decomposition under high voltage endlessly exacerbate interfacial ramifications and structu ral degradation of high energy-density Li-rich layered oxide(LLO),leading to voltage and capac... Oxygen release and electrolyte decomposition under high voltage endlessly exacerbate interfacial ramifications and structu ral degradation of high energy-density Li-rich layered oxide(LLO),leading to voltage and capacity fading.Herein,the dual-strategy of Cr,B complex coating and local gradient doping is simultaneously achieved on LLO surface by a one-step wet chemical reaction at room temperature.Density functional theory(DFT)calculations prove that stable B-O and Cr-O bonds through the local gradient doping can significantly reduce the high-energy O 2p states of interfacial lattice O,which is also effective for the near-surface lattice O,thus greatly stabilizing the LLO surface,Besides,differential electrochemical mass spectrometry(DEMS)indicates that the Cr_(x)B complex coating can adequately inhibit oxygen release and prevents the migration or dissolution of transition metal ions,including allowing speedy Li^(+)migration,The voltage and capacity fading of the modified cathode(LLO-C_(r)B)are adequately suppressed,which are benefited from the uniformly dense cathode electrolyte interface(CEI)composed of balanced organic/inorganic composition.Therefore,the specific capacity of LLO-CrB after 200 cycles at 1C is 209.3 mA h g^(-1)(with a retention rate of 95.1%).This dual-strategy through a one-step wet chemical reaction is expected to be applied in the design and development of other anionic redox cathode materials. 展开更多
关键词 Lithium-rich layered oxide cathode One-step wet chemical reaction Surface coating Local gradient doping Interfacial oxygen
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From lab to fab:A large language model for chemical engineering 被引量:1
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作者 Jibin Zhou Feiyang Xu +10 位作者 Zhijun Chang Duiping Liu Lulu Li Jian Cui Yi Li Xin Li Li Qian Zhixiong Zhang Guoping Hu Mao Ye Zhongmin Liu 《Chinese Journal of Catalysis》 2025年第6期159-173,共15页
The development of chemical technologies,which involves a multistage process covering laboratory research,scale‐up to industrial deployment,and necessitates interdisciplinary collaboration,is often accompanied by sub... The development of chemical technologies,which involves a multistage process covering laboratory research,scale‐up to industrial deployment,and necessitates interdisciplinary collaboration,is often accompanied by substantial time and economic costs.To address these challenges,in this work,we report ChemELLM,a domain‐specific large language model(LLM)with 70 billion parameters for chemical engineering.ChemELLM demonstrates state‐of‐the‐art performance across critical tasks ranging from foundational understanding to professional problem‐solving.It outperforms mainstream LLMs(e.g.,O1‐Preview,GPT‐4o,and DeepSeek‐R1)on ChemEBench,the first multidimensional benchmark for chemical engineering,which encompasses 15 dimensions across 101 distinct essential tasks.To support robust model development,we curated ChemEData,a purpose‐built dataset containing 19 billion tokens for pre‐training and 1 billion tokens for fine‐tuning.This work establishes a new paradigm for artificial intelligence‐driven innovation,bridging the gap between laboratory‐scale innovation and industrial‐scale implementation,thus accelerating technological advancement in chemical engineering.ChemELLM is publicly available at https://chemindustry.iflytek.com/chat. 展开更多
关键词 Large language model chemical engineering Process development Multidimensional benchmark Domain adaptation
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