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Strategies and Advances in the Biomimetic Synthesis of Natural Products 被引量:1
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作者 Li-Jun Hu Zhi-Zhang Duan +2 位作者 Ying Wang Wen-Cai Ye Chun-Tao Che 《Engineering》 2025年第1期30-36,共7页
Natural products,with their remarkable structural and biological diversity,have historically served as a vital bridge between chemistry,the life sciences,and medicine.They not only provide essential scaffolds for drug... Natural products,with their remarkable structural and biological diversity,have historically served as a vital bridge between chemistry,the life sciences,and medicine.They not only provide essential scaffolds for drug discovery but also inspire innovative strategies in drug development.The biomimetic synthesis of natural products employs principles from biomimicry,applying inspiration from biogenetic processes to design synthetic strategies that mimic biosynthetic processes.Biomimetic synthesis is a highly efficient approach in synthetic chemistry,as it addresses critical challenges in the synthesis of structurally complex natural products with significant biological and medicinal importance.It has gained widespread attention from researchers in chemistry,biology,pharmacy,and related fields,underscoring its interdisciplinary impact.In this perspective,we present recent advances and challenges in the biomimetic synthesis of natural products,along with the significance and prospects of this field,highlighting the transformative potential of biomimetic synthesis strategies for both chemical and biosynthetic approaches to natural product synthesis in the pursuit of novel therapeutic agents. 展开更多
关键词 Natural products Natural product synthesis Biomimetic synthesis Biomimetic synthesis strategy
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A comprehensive review on the scalable and sustainable synthesis of covalent organic frameworks
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作者 Yujie Wang Haoran Wang +3 位作者 Yanni Liu Manhua Peng Hongwei Fan Hong Meng 《Chinese Chemical Letters》 2025年第8期190-206,共17页
Covalent organic frameworks(COFs),as a burgeoning class of crystalline porous materials have attracted widespread interest due to their designable structures and customized functions.However,the solvothermal synthesis... Covalent organic frameworks(COFs),as a burgeoning class of crystalline porous materials have attracted widespread interest due to their designable structures and customized functions.However,the solvothermal synthesis of COFs is often time-consuming and conducted at a high temperature within a sealed vessel,and also requires a large amount of poisonous solvents,which is generally not available for scaling-up production and commercial application.In recent years,great efforts have been made to explore simple,green,and efficient approaches for COFs synthesis.In this comprehensive review,we summarized the advances in emergent strategies by highlighting their distinct features.Fundamental issues and future directions are also discussed with the object of bringing implications for large-scale and sustainable fabrication of COFs. 展开更多
关键词 Covalent organic frameworks Large-scaleproduction Green synthesis Efficient synthesis Ambient synthesis
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Ultrafast Joule heating technology for functional nanomaterials synthesis:Recent progress,challenges,and perspectives
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作者 Yuyu Liu Ruting Lin +6 位作者 Baoyi Guo Chen Chen Qiujin Wu Xiaofeng Zhang Qiufeng Huang Ibrahim Saana Amiinu Tingting Liu 《Materials Reports(Energy)》 2025年第4期11-34,共24页
Ultrafast Joule heating(JH)has emerged as a powerful and scalable platform for rapid thermal processing of advanced nanomaterials.By delivering transient,high-intensity electrical pulses,JH induces ultrafast heating a... Ultrafast Joule heating(JH)has emerged as a powerful and scalable platform for rapid thermal processing of advanced nanomaterials.By delivering transient,high-intensity electrical pulses,JH induces ultrafast heating and cooling rates on the order of milliseconds,facilitating nonequilibrium phase transitions,defect modulation,and tailored nanostructural evolution.This technique offers unprecedented control over material synthesis and has been successfully applied to a broad spectrum of functional property-driven materials,including graphene,single-atom catalysts,transition metal carbides,oxides,nitrides,phosphides,and chalcogenides,as well as complex multicomponent frameworks such as high-entropy alloys.This review systematically explores the principles governing JH,highlights recent advances in its application to diverse materials systems,and critically assesses current limitations related to process uniformity,scalability,and mechanistic understanding.Particular attention is given to its intrinsic advantages,including energy efficiency,fast rate,environmental sustainability,and compatibility with sustainable manufacturing.Finally,we propose guidance for expanding the utility of JH for new materials discovery,including integration with in-situ diagnostics,theoretical compatibility and data-driven optimization of synthesis to effectively correlate structure-property relationships. 展开更多
关键词 ELECTROCATALYSIS Energy storage and conversion Joule heating Materials synthesis Nanomaterials and ultrafast synthesis
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Improved one-pot protein synthesis enabled by a more precise assessment of peptide arylthioester reactivity
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作者 Min Fu Ruihan Wang +7 位作者 Wenqiang Liu Sen Zhou Chunhong Zhong Yaohao Li Pan He Xin Li Shiying Shang Zhongping Tan 《Chinese Chemical Letters》 2025年第7期354-357,共4页
By investigating 17 peptide arylthioesters that were previously challenging to produce,this study reveals a clear correlation between increased ligation activity and decreased pKa values of their corresponding arylthi... By investigating 17 peptide arylthioesters that were previously challenging to produce,this study reveals a clear correlation between increased ligation activity and decreased pKa values of their corresponding arylthiols.The observed differences are attributed to variations in thioester bond strength and steric hindrance.These insights have led to the development of an improved one-pot chemical protein synthesis approach that leverages the reactivity differences between peptide arylthioesters with C-terminal Ala-SPh(4-NO_(2))and Ala-S-Ph(2,6-diCH_(3)).This approach eliminates the need for thiol-thioester exchange and additive removal steps while enabling in situ desulfurization,thereby significantly simplifying the protein synthesis process. 展开更多
关键词 Chemical protein synthesis Arylthioesters One-pot synthesis Native chemical ligation In situ desulfurization
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Highly fused tetracyclic diterpenoid natural products:Diverse biosynthesis and total synthesis
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作者 Yun-Hong Yu Yu Peng Wei-Dong Z.Li 《Chinese Chemical Letters》 2025年第10期109-124,共16页
A category of highly fused diterpenoid natural products possessing a characteristic perhydropyrene-like or rearranged tetracyclic skeleton structure are distributed in different life forms.Compared to traditional poly... A category of highly fused diterpenoid natural products possessing a characteristic perhydropyrene-like or rearranged tetracyclic skeleton structure are distributed in different life forms.Compared to traditional polycyclic diterpenoids,their biosynthetic pathways are quite unique and diverse.Chemists have pinpointed a range of this type of unusual diterpenoids:cycloamphilectanes and isocycloamphilectanes,kempenes and rippertanes,hydropyrene and hydropyrenol,along with recently disclosed cephalotanes.This review describes developments in this field and discusses the challenges associated with synthesizing this class of highly complex compounds. 展开更多
关键词 Tetracyclic diterpenoid Perhydropyrene skeleton Natural products BIOsynthesis Total synthesis Cephalotanes
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Double redox-mediated intrinsic semiconductor photocatalysis:Practical semi-heterogeneous synthesis
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作者 Xin He Feng Liu Tao Tu 《Chinese Chemical Letters》 2025年第3期1-2,共2页
Photoredox catalysis has made significant advances in stateof-the-art chemical synthesis,drawing energy from inexhaustible light and enabling various organic transformations to occur under mild reaction conditions.Ove... Photoredox catalysis has made significant advances in stateof-the-art chemical synthesis,drawing energy from inexhaustible light and enabling various organic transformations to occur under mild reaction conditions.Over the past few years,a variety of homogeneous and heterogeneous photocatalysts have been applied in the photoredox catalysis.Heterogeneous photoredox catalysis offers advantages such as easy separation and superior recyclability compared to homogeneous counterparts,although homogenous catalysts are usually associated with higher activities and selectivity.From a practical perspective,an optimal photoredox catalytic system would integrate the advantages of both homogeneous and heterogeneous cases. 展开更多
关键词 organic transformations double redox mediated semi heterogeneous synthesis homogenous catalysts homogeneous heterogeneous photocatalysts photoredox catalysisheterogeneous photoredox catalysis chemical synthesisdrawing
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Microwave-enabled rapid,continuous,and substrate-free synthesis of few-layer graphdiyne nanosheets for enhanced potassium metal battery performance 被引量:1
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作者 KONG Ya ZHANG Shi-peng +6 位作者 YIN Yu-ling ZHANG Zi-xuan FENG Xue-ting DING Feng ZHANG Jin TONG Lian-ming GAO Xin 《新型炭材料(中英文)》 北大核心 2025年第3期642-650,共9页
Graphdiyne(GDY)is a two-dimensional carbon allotrope with exceptional physical and chemical properties that is gaining increasing attention.However,its efficient and scalable synthesis remains a significant challenge.... Graphdiyne(GDY)is a two-dimensional carbon allotrope with exceptional physical and chemical properties that is gaining increasing attention.However,its efficient and scalable synthesis remains a significant challenge.We present a microwave-assisted approach for its continuous,large-scale production which enables synthesis at a rate of 0.6 g/h,with a yield of up to 90%.The synthesized GDY nanosheets have an average diameter of 246 nm and a thickness of 4 nm.We used GDY as a stable coating for potassium(K)metal anodes(K@GDY),taking advantage of its unique molecular structure to provide favorable paths for K-ion transport.This modification significantly inhibited dendrite formation and improved the cycling stability of K metal batteries.Full-cells with perylene-3,4,9,10-tetracarboxylic dianhydride(PTCDA)cathodes showed the clear superiority of the K@GDY anodes over bare K anodes in terms of performance,stability,and cycle life.The K@GDY maintained a stable voltage plateau and gave an excellent capacity retention after 600 cycles with nearly 100%Coulombic efficiency.This work not only provides a scalable and efficient way for GDY synthesis but also opens new possibilities for its use in energy storage and other advanced technologies. 展开更多
关键词 Graphdiyne Microwave-assisted synthesis Few-layer Potassium metal battery Dendrite-free
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Low-cost and fluoride-free synthesis of MFI zeolite nanosheets with enhanced stability for benzene alkylation with ethanol 被引量:2
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作者 Peng Zhu Cun Liu +5 位作者 Yiren Yu Guoshu Gao Yumeng Zhao Xiongfu Zhang Guodong Liu Guohui Yang 《Journal of Energy Chemistry》 2025年第1期458-468,共11页
Zeolite nanosheets with a short b-axis thickness are highly desirable in lots of catalytic reactions due to their reduced diffusion resistance. Nevertheless, conventional synthesis methods usually require expensive st... Zeolite nanosheets with a short b-axis thickness are highly desirable in lots of catalytic reactions due to their reduced diffusion resistance. Nevertheless, conventional synthesis methods usually require expensive structure-directing agents(SDAs), pricey raw materials, and eco-unfriendly fluorine-containing additives. Here, we contributed a cost-effective and fluoride-free synthesis method for synthesizing high-quality MFI zeolite nanosheets through a Silicalite-1(Sil-1) seed suspension and urea cooperative strategy, only with inexpensive colloidal silica as the Si source. Our approach was effective for synthesizing both Sil-1 and aluminum-containing ZSM-5 nanosheets. By optimizing key synthesis parameters,including seed aging time, seed quantity, and urea concentration, we achieved precise control over the crystal face aspect ratio and b-axis thickness. We also revealed a non-classical oriented nanosheet growth mechanism, where Sil-1 seeds induced the formation of quasi-ordered precursor particles, and the(010)crystal planes of these particles facilitated urea adsorption, thereby promoting c-axis-oriented growth.The obtained ZSM-5 nanosheets exhibited exceptional catalytic performance in the benzene alkylation with ethanol, maintaining stability for over 500 h, which is 5 times longer than traditional ZSM-5 catalysts. Furthermore, large-scale production of ZSM-5 nanosheets was successfully carried out in a 3 L highpressure autoclave, yielding samples consistent with those from laboratory-scale synthesis. This work marks a significant step forward in the sustainable and efficient production of MFI nanosheets using inexpensive and environmentally friendly raw materials, offering the broad applicability in catalysis. 展开更多
关键词 MFI zeolite ZSM-5 NANOSHEETS Scale-up synthesis Aromatic alkylation
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A review of carbon dots in synthesis strategies,photoluminescence mechanisms,and applications in wastewater treatment 被引量:1
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作者 Ping Wang Chunmao Chen +1 位作者 Hongwei Ren Erhong Duan 《Chinese Chemical Letters》 2025年第9期140-170,共31页
Urbanization and industrialization have escalated water pollution,threatening ecosystems and human health.Water pollution not only degrades water quality but also poses long-term risks to human health through the food... Urbanization and industrialization have escalated water pollution,threatening ecosystems and human health.Water pollution not only degrades water quality but also poses long-term risks to human health through the food chain.The development of efficient wastewater detection and treatment methods is essential for mitigating this environmental hazard.Carbon dots(CDs),as emerging carbon-based nanomaterials,exhibit properties such as biocompatibility,photoluminescence(PL),water solubility,and strong adsorption,positioning them as promising candidates for environmental monitoring and management.Particularly in wastewater treatment,their optical and electron transfer properties make them ideal for pollutant detection and removal.Despite their potential,comprehensive reviews on CDs'role in wastewater treatment are scarce,often lacking detailed insights into their synthesis,PL mechanisms,and practical applications.This review systematically addresses the synthesis,PL mechanisms,and wastewater treatment applications of CDs,aiming to bridge existing research gaps.It begins with an overview of CDs structure and classification,essential for grasping their properties and uses.The paper then explores the pivotal PL mechanisms of CDs,crucial for their sensing capabilities.Next,comprehensive synthesis strategies are presented,encompassing both top-down and bottom-up strategies such as arc discharge,chemical oxidation,and hydrothermal/solvothermal synthesis.The diversity of these methods highlights the potential for tailored CDs production to suit specific environmental applications.Furthermore,the review systematically discusses the applications of CDs in wastewater treatment,including sensing,inorganic removal,and organic degradation.Finally,it delves into the research prospects and challenges of CDs,proposing future directions to enhance their role in wastewater treatment. 展开更多
关键词 Carbon dots Classification synthesis strategies PL mechanism Sensing ADSORPTION PHOTOCATALYSIS
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Controllable synthesis of hydrogen-bonded organic framework encapsulated enzyme for continuous production of chiral hydroxybutyric acid in a two-stage cascade microreactor 被引量:1
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作者 Danyang Zhao Qiangqiang Xue +1 位作者 Yujun Wang Guangsheng Luo 《Chinese Journal of Chemical Engineering》 2025年第1期175-184,共10页
Constructing a framework carrier to stabilize protein conformation,induce high embedding efficiency,and acquire low mass-transfer resistance is an urgent issue in the development of immobilized enzymes.Hydrogen-bonded... Constructing a framework carrier to stabilize protein conformation,induce high embedding efficiency,and acquire low mass-transfer resistance is an urgent issue in the development of immobilized enzymes.Hydrogen-bonded organic frameworks(HOFs)have promising application potential for embedding enzymes.In fact,no metal involvement is required,and HOFs exhibit superior biocompatibility,and free access to substrates in mesoporous channels.Herein,a facile in situ growth approach was proposed for the self-assembly of alcohol dehydrogenase encapsulated in HOF.The micron-scale bio-catalytic composite was rapidly synthesized under mild conditions(aqueous phase and ambient temperature)with a controllable embedding rate.The high crystallinity and periodic arrangement channels of HOF were preserved at a high enzyme encapsulation efficiency of 59%.This bio-composite improved the tolerance of the enzyme to the acid-base environment and retained 81%of its initial activity after five cycles of batch hydrogenation involving NADH coenzyme.Based on this controllably synthesized bio-catalytic material and a common lipase,we further developed a two-stage cascade microchemical system and achieved the continuous production of chiral hydroxybutyric acid(R-3-HBA). 展开更多
关键词 Hydrogen-bonded organic framework Immobilized enzyme synthesis Chiral hydroxycarboxylic acid BIOCATALYSIS Nanostructure
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Effects of hypoxia stress on the milk synthesis in bovine mammary epithelial cells 被引量:1
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作者 Yanshan Jin Zhuolin Liu +3 位作者 Ziyan Yang Lizhu Fang Feng-Qi Zhao Hongyun Liu 《Journal of Animal Science and Biotechnology》 2025年第3期1142-1159,共18页
Background Milk synthesis is an energy-intensive process influenced by oxygen availability.This study investigates how hypoxia affects milk synthesis in BMECs,focusing on key genes involved in lactation and energy met... Background Milk synthesis is an energy-intensive process influenced by oxygen availability.This study investigates how hypoxia affects milk synthesis in BMECs,focusing on key genes involved in lactation and energy metabolism.Methods BMECs were cultured in a normoxic environment and then transferred to a hypoxia chamber with 1%O2 for specified durations.The study evaluated cellular responses through various molecular experiments and RNA sequencing.Small interfering RNA was employed to knock down HIF-1αto investigate whether the lactation-related phenotype alteration depends on HIF-1α.Results Hypoxia disrupted milk protein production by reducing mTOR/P70S6K/4EBP1 signaling and downregulating genes critical for amino acid transport and protein synthesis.Triglyceride synthesis increased due to enhanced fatty acid uptake and the upregulation of regulatory proteins,including FASN and PPARγ.Although glucose uptake was elevated under hypoxia,key enzymes for lactose synthesis were downregulated,suggesting a redirection of glucose toward energy production.Mitochondrial function was impaired under hypoxia,with reduced gene expression in TCA cycle,ETC,cytosol-mitochondrial transport,decreased ATP levels,increased ROS levels,and structural alterations.Additionally,lipid synthesis and glucose uptake depend on HIF-1α,while milk protein synthesis alterations occurred independently of HIF-1α.Conclusions Hypoxia alters milk synthesis in BMECs by disrupting milk protein synthesis,enhancing lipid metabolism,and impairing energy production.These findings provide valuable insights into the molecular mechanisms underlying the effect of oxygen deprivation on lactation efficiency,offering potential targets for mitigating hypoxic stress in the mammary glands of dairy animals. 展开更多
关键词 Hypoxic stress HIF-1Α Low oxygen Milk synthesis
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Navigating the pathways:TAR-DNA-binding-protein-43 aggregation,axonal transport,and local synthesis in amyotrophic lateral sclerosis pathology
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作者 Ori Bar Avi Eran Perlson 《Neural Regeneration Research》 SCIE CAS 2025年第10期2921-2922,共2页
Neurons are highly polarized cells with axons reaching over a meter long in adult humans.To survive and maintain their proper function,neurons depend on specific mechanisms that regulate spatiotemporal signaling and m... Neurons are highly polarized cells with axons reaching over a meter long in adult humans.To survive and maintain their proper function,neurons depend on specific mechanisms that regulate spatiotemporal signaling and metabolic events,which need to be carried out at the right place,time,and intensity.Such mechanisms include axonal transport,local synthesis,and liquid-liquid phase separations.Alterations and malfunctions in these processes are correlated to neurodegenerative diseases such as amyotrophic lateral sclerosis(ALS). 展开更多
关键词 synthesis LOCAL AGGREGATION
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Progress in the Total Synthesis of Cephalotane Diterpenoid Natural Products
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作者 Ding Yiming Zhang Tingrong +1 位作者 Zhang Jingwei Deng Jun 《有机化学》 北大核心 2025年第6期2048-2073,共26页
Continuous research on Cephalotaxus plants has ultimately led to the US food and drug administration (FDA) ap-provalof homoharringtonine in 2012 for the treatment of chronic myeloid leukemia. Additionally, another imp... Continuous research on Cephalotaxus plants has ultimately led to the US food and drug administration (FDA) ap-provalof homoharringtonine in 2012 for the treatment of chronic myeloid leukemia. Additionally, another important class of natural products from Cephalotaxus plants is cephalotane diterpenoids. Since the discovery of the first member, harring-tonolide,in 1978, cephalotane diterpenoids have garnered significant attention from the scientific community due to their re-markableanti-cancer activity. The unique structural features of cephalotane diterpenoids, a 7/6/5/6-fused tetracyclic carbon skeleton and a bridged lactone, make them ideal targets for synthetic chemists. Successfully synthesizing these complex diterpenoids is of great importance for the discovery and development of anti-tumor drugs. To date, ten research groups have completed the total synthesis of 24 cephalotane diterpenoids. The latest progress in the total synthesis of cephalotane diterpe-noidsis reviewed, showcasing the importance of these innovative synthetic strategies in the efficient synthesis of complex natural products and their potential significance in advancing the field of drug discovery. 展开更多
关键词 cephalotane diterpenoids total synthesis anti-cancer activity harringtonolide Cephalotaxus
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Mechanism for Hydrothermal-carbothermal Synthesis of AlN Nanopowders
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作者 FENG Guanzheng YANG Jian +3 位作者 ZHOU Du CHEN Qiming XU Wentao ZHOU Youfu 《无机材料学报》 北大核心 2025年第1期104-110,I0009-I0011,共10页
Currently,the carbothermal reduction-nitridation(CRN)process is the predominant method for preparing aluminum nitride(AlN)powder.Although AlN powder prepared by CRN process exhibits high purity and excellent sintering... Currently,the carbothermal reduction-nitridation(CRN)process is the predominant method for preparing aluminum nitride(AlN)powder.Although AlN powder prepared by CRN process exhibits high purity and excellent sintering activity,it also presents challenges such as the necessity for high reaction temperatures and difficulties in achieving uniform mixing of its raw materials.This study presents a comprehensive investigation into preparation process of AlN nanopowders using a combination of hydrothermal synthesis and CRN.In the hydrothermal reaction,a homogeneous composite precursor consisting of carbon and boehmite(γ-AlOOH)is synthesized at 200℃using aluminum nitrate as the aluminum source,sucrose as the carbon source,and urea as the precipitant.During the hydrothermal process,the precursor develops a core-shell structure,with boehmite tightly coated with carbon(γ-AlOOH@C)due to electrostatic attraction.Compared with conventional precursor,the hydrothermal hybrid offers many advantages,such as ultrafine particles,uniform particle size distribution,good dispersion,high reactivity,and environmental friendliness.The carbon shell enhances thermodynamic stability of γ-Al_(2)O_(3) compared to the corundum phase(α-Al_(2)O_(3))by preventing the loss of the surface area in alumina.This stability enables γ-Al_(2)O_(3) to maintain high reactivity during CRN process,which initiates at 1300℃,and concludes at 1400℃.The underlying mechanisms are substantiated through experiments and thermodynamic calculations.This research provides a robust theoretical and experimental foundation for the hydrothermal combined carbothermal preparation of non-oxide ceramic nanopowders. 展开更多
关键词 aluminum nitride carbothermal reduction-nitridation MECHANISM hydrothermal synthesis PRECURSOR
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Real-Time Smart Meter Abnormality Detection Framework via End-to-End Self-Supervised Time-Series Contrastive Learning with Anomaly Synthesis
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作者 WANG Yixin LIANG Gaoqi +1 位作者 BI Jichao ZHAO Junhua 《南方电网技术》 北大核心 2025年第7期62-71,89,共11页
The rapid integration of Internet of Things(IoT)technologies is reshaping the global energy landscape by deploying smart meters that enable high-resolution consumption monitoring,two-way communication,and advanced met... The rapid integration of Internet of Things(IoT)technologies is reshaping the global energy landscape by deploying smart meters that enable high-resolution consumption monitoring,two-way communication,and advanced metering infrastructure services.However,this digital transformation also exposes power system to evolving threats,ranging from cyber intrusions and electricity theft to device malfunctions,and the unpredictable nature of these anomalies,coupled with the scarcity of labeled fault data,makes realtime detection exceptionally challenging.To address these difficulties,a real-time decision support framework is presented for smart meter anomality detection that leverages rolling time windows and two self-supervised contrastive learning modules.The first module synthesizes diverse negative samples to overcome the lack of labeled anomalies,while the second captures intrinsic temporal patterns for enhanced contextual discrimination.The end-to-end framework continuously updates its model with rolling updated meter data to deliver timely identification of emerging abnormal behaviors in evolving grids.Extensive evaluations on eight publicly available smart meter datasets over seven diverse abnormal patterns testing demonstrate the effectiveness of the proposed full framework,achieving average recall and F1 score of more than 0.85. 展开更多
关键词 abnormality detection cyber-physical security anomaly synthesis contrastive learning time-series
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Ethanol-assisted direct synthesis of wafer-scale nitrogen-doped graphene for III-nitride epitaxial growth
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作者 WEI Wen-ze GAO Xiang +4 位作者 YU Chao-jie SUN Xiao-li WEI Tong-bo JIA Li SUN Jing-yu 《新型炭材料(中英文)》 北大核心 2025年第3期678-687,共10页
Among the synthesis techniques for graphene,chemical vapor deposition(CVD)enables the direct growth of graphene films on insulating substrates.Its advantages include uniform coverage,high quality,scalability,and compa... Among the synthesis techniques for graphene,chemical vapor deposition(CVD)enables the direct growth of graphene films on insulating substrates.Its advantages include uniform coverage,high quality,scalability,and compatibility with industrial processes.Graphene is chemically inert and has a zero-bandgap which poses a problem for its use as a functional layer,and nitrogen doping has become an important way to overcome this.Post-plasma treatment has been explored for the synthesis of nitrogen-doped graphene,but the procedures are intricate and not suitable for large-scale production.We report the direct synthesis of nitrogen-doped graphene on a 4-inch sapphire wafer by ethanol-assisted CVD employing pyridine as the carbon feedstock,where the nitrogen comes from the pyridine and the hydroxyl group in ethanol improves the quality of the graphene produced.Additionally,the types of nitrogen dopant produced and their effects on III-nitride epitaxy were also investigated,resulting in the successful illumination of LED devices.This work presents an effective synthesis strategy for the preparation of nitrogen-doped graphene,and provides a foundation for designing graphene functional layers in optoelectronic devices. 展开更多
关键词 III-nitride epitaxy Direct synthesis Ethanol-assisted CVD LED devices Nitrogen-doped graphene
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Synthesis and crystal structure characterization of yttrium imido complex:The reactivity of 2-substituted-1-amino-o-carborane with yttrium dialkyl complex
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作者 GUO Liping 《无机化学学报》 北大核心 2025年第7期1409-1415,共7页
2-substituted-1-amino-o-carboranes 2-R-1-NH_(2)-o-C_(2)B_(10)H_(10)(R=CH_(3),1a;R=Ph,1b)were synthesized and the reactions of these compounds with the yttrium dialkyl complex[Y(L)(CH_(2)SiMe3)_(2)](L=[2-(2,5-Me_(2)C_(... 2-substituted-1-amino-o-carboranes 2-R-1-NH_(2)-o-C_(2)B_(10)H_(10)(R=CH_(3),1a;R=Ph,1b)were synthesized and the reactions of these compounds with the yttrium dialkyl complex[Y(L)(CH_(2)SiMe3)_(2)](L=[2-(2,5-Me_(2)C_(4)H_(2)N)C_(6)H4NC(Ph)=NDipp]-,Dipp=2,6-iPr_(2)C_(6)H_(3))were investigated.The 1H NMR spectroscopy indicate that the reaction of ytrrium dialkyl complex with one equivalent of 2-R-1-NH_(2)-o-C_(2)B_(10)H_(10) produce the mixture of ytrrium alkyl-amido complex[Y(L)(2-R-1-NH-o-C_(2)B_(10)H_(10))(CH_(2)SiMe3)](R=CH_(3),2a;R=Ph,2b)and bis(amido)complex[Y(L)(2-R-1-NH-o-C_(2)B_(10)H_(10))_(2)](R=CH_(3),3a;R=Ph,3b).The yttrium bridging imido complex[Y(L)(2-CH_(3)-1-N-o-C_(2)B_(10)H_(10))]_(2)(4a)was obtained by heating the mixture at 55℃for 12 h.Complex 3a was isolated and characterized by treating the yttrium dialkyl complex with two equivalents of 1a.The structures of complexes 3a and 4a were verified by single-crystal Xray diffraction.CCDC:2424136,3a;2424137,4a. 展开更多
关键词 yttrium imide O-CARBORANE synthesis structure characterization
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Synthesis of C2-Spiroindolines Based on the Cascade Reaction of 2-Aryl-3H-indoles with Cyclopropanols
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作者 Xueying Yang Yuanshuang Xu +1 位作者 Xinying Zhang Xuesen Fan 《有机化学》 北大核心 2025年第2期694-706,共13页
A novel synthesis of C2-spiroindoline derivatives based on the cascade reaction of 2-aryl-3H-indoles with cyclo- propanols is presented. The formation of product involves Rh(III)-catalyzed aryl C(sp2)—H bond alkylati... A novel synthesis of C2-spiroindoline derivatives based on the cascade reaction of 2-aryl-3H-indoles with cyclo- propanols is presented. The formation of product involves Rh(III)-catalyzed aryl C(sp2)—H bond alkylation of 2-aryl- 3H-indole, which is followed by intramolecular spiroannulation. In this tandem process, cyclopropanol acts as not only an alkylating agent but also a masked nucleophile to take part in the construction of the spirocyclic scaffold. Meanwhile, air acts as an economical and sustainable oxidant to promote the regeneration of the active catalyst. By using this method, hybrid compounds containing the central scaffolds of some clinical drugs were prepared effectively. In general, this newly developed method has advantages such as easily obtainable substrates, concise synthetic procedure, excellent atom-economy, good compatibility with diverse functional groups and ready scalability. 展开更多
关键词 C2-spiroindolines synthesis C-H bond activation cascade reaction 2-aryl-3H-indoles CYCLOPROPANOLS
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Water-promoted green synthesis of heterocyclicβ-ketosulfides
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作者 GU Wen ZHANG Shu-ting +2 位作者 YANG Fei ZUO Yi-wei ZHAO Zhi-gang 《化学研究与应用》 北大核心 2025年第5期1274-1287,共14页
A strategy for the green synthesis of heterocyclicβ-ketosulfides via nucleophilic substitution ofα-halogenated ketone with het-eroaryl thiols in water media is presented.Compared with the available literature report... A strategy for the green synthesis of heterocyclicβ-ketosulfides via nucleophilic substitution ofα-halogenated ketone with het-eroaryl thiols in water media is presented.Compared with the available literature reports,this new method had the advantages of base-free,additives-free,simple operation,mild condition,greenness,high efficiency,tolerance of a broad scope of substrates.Furth-more,the reaction could easily be scaled up in gram scale and the products also could easily transformed to other useful organic compounds.Mechanism investigation indicated that the tautomerism of pyrimidine-2-thiol to pyrimidine-2(1H)-thione and the hy-drogen bonds played important roles in the reaction. 展开更多
关键词 green synthesis water media heterocyclicβ-ketosulfides base-free
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Recent progress and future directions in nanoglass materials: A deep insight into synthesis, characterization, and application
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作者 Anshuman Mishra Marisa A.Frechero +2 位作者 Arnaud Caron Pravin Kumar Singh Ashutosh Tiwari 《Nanotechnology and Precision Engineering》 2025年第1期132-162,共31页
This review article provides a comprehensive examination of the most recent advances in research on nanoglasses,including the methods used to create these materials,their characteristics,and their diverse range of use... This review article provides a comprehensive examination of the most recent advances in research on nanoglasses,including the methods used to create these materials,their characteristics,and their diverse range of uses.An overview of the current trends in nanoglass research connects them to the Sustainable Development Goals,highlighting the current relevance of this topic.The process of manufacturing nanoglasses is explained in depth,highlighting advanced approaches such as inert gas condensation and severe plastic deformation,among other techniques.The prime focus of this review is on analyzing the various dimensions of nanoglass materials,including their structural dynamics and electrical configurations,and how these features contribute to their exceptional thermal stability and mechanical strength.The magnetic characteristics of nanoglasses are examined,highlighting their potential for driving innovation across multiple industries.The primary emphasis is on the biological usefulness of nanoglasses,specifically examining their bioactivity and interaction with biological components,and emphasizing their growing use in nanoscale biomedical applications.With regard to the practical applications of nanoglasses,there are specific discussions of their contributions to biological evaluation,wound healing,catalysis,and environmental sustainability.There is an emphasis on the durability and resistance of nanoglasses in these contexts.The comprehensive overview of nanoglasses provided in this article highlights their significance as revolutionary materials in fields of science and technology.The potential of nanoglasses to contribute to a future that is more sustainable and health oriented is indicated.The article ends by discussing the future directions for nanoglass research and looks forward to the promising possibilities for further investigation and innovation. 展开更多
关键词 NANOGLASS synthesis CHARACTERIZATION NANOCATALYSIS BIOMEDICINE
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