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Advances of graphdiyne-supported metal catalysts in thermocatalytic reactions

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Nano research 2024年第4期17卷 2223-2233页

作者： Jia Yu Yida Yang Yuliang Li Changyan Cao Weiguo Song Beijing National Laboratory for Molecular sciences CAS Research/Education Center for Excellence in Molecular SciencesLaboratory of Molecular Nanostructures and NanotechnologyInstitute of ChemistryChinese Academy of SciencesBeijing 100190China School of Chemical sciences University of Chinese Academy of SciencesBeijing 100049China Beijing National Laboratory for Molecular sciences CAS Research/Education Center for Excellence in Molecular SciencesLaboratory of organic solidsInstitute of ChemistryChinese Academy of SciencesBeijing 100190China

Supported metal catalysts are widely used in the modern chemical industry.The electronic interaction between supports and active components is of great significance for heterogeneous catalysis.Graphdiyne(GDY),a new type of carbon allotrope with sp-hybridized carbon atoms,πconjugate structure,and electron transmission capability,is a promising candidate as catalyst support.Recent years have witnessed the rapid progress of GDY-supported metal catalysts for different catalysis reactions.Considering that most processes in the current chemical industry are thermocatalytic reactions,we herein give an overview about the advances and particular characteristics of GDY-supported catalysts in these reactions.The geometric structure and electronic properties of GDY are first introduced.Then,the synthesis methods for GDY-supported metal catalysts and their applications in thermocatalytic reactions are discussed,in which the effect of electronic interaction on catalytic performance is highlighted.Finally,the current challenges and future directions of GDY-supported metal catalysts for thermocatalysis are proposed.It is expected that this review will enrich our understanding of the advances of GDY as a superior support for metal catalysts in thermocatalytic reactions.

关键词： graphdiyne metal catalysts thermocatalytic reactions heterogeneous catalysis

Duphaston as a suitable medication for women taking intracytoplasmic sperm injection to treat infertility

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生殖与发育医学(英文) 2024年第2期8卷 89-92页

作者： Naserpour Leila Berjis Katayon Moud Sanaz Soleymani Jannatifar Rahil Department of Reproductive Biology Academic Center for Education Culture and Research (ACECR) Qom Branch Qom Iran Infertility Treatment center Academic Center for Education Culture and Research (ACECR) Qom Branch Qom Iran Cellular and Molecular research center Qom University of Medical Sciences Qom Iran Midwifery Ward Infertility Treatment Center Academic Center for Education Culture and Research (ACECR) Qom Branch Qom Iran

Objective: Duphaston is used as an alternative to gonadotropin-releasing hormone (GnRH) antagonists for suppressing premature luteinizing hormone (LH) surges. This study aimed to compare the efficacy of Duphaston protocols with that of Cetrotide in suppressing the LH surge.Methods: In this retrospective cross-sectional study, 669 infertile women (aged 25-40 years) were administered recombinant follicle-stimulating hormone (rFSH) from the third day of their menstrual cycle. After the follicular diameter reached 13 to 14 mm, Cetrotide was prescribed orally to the control subjects, also case subjects took Duphaston orally. The retrieved oocytes were fertilized by an intracytoplasmic sperm injection (ICSI).Results: The levels of FSH, LH, and estradiol did not differ significantly between the groups (P >0.05). However, the findings indicated that Duphaston led to greater oocyte retrieval than Cetrotide (P = 0.006). However, the number of mature oocytes and viable embryos in the case subjects did not reach a significant difference compared to that in the control subjects (P >0.05). The number of good-quality embryos (stage 1) was significantly higher in the case subjects (P = 0.04). In addition, there is no significant difference in the chemical, clinical pregnancy, implantation rate, and miscarriage rate between both groups (P >0.05).Conclusion: Duphaston could be utilized as a suitable medication rather than a GnRH antagonist in women subjected to controlled ovarian hyperstimulation.

关键词： Duphaston Cetrotide Progesterone protocol Ovarian hyperstimulation GnRH antagonist

Ni-Catalyzed Enantioselective Difunctionalization of Alkynes to Azepine Derivatives Bearing a Quaternary center and an Unprotected Imine

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Chinese Journal of Chemistry 2024年第8期42卷 873-878页

作者： Jian Long Zhiwu Lu Xiao-Lin Li Peng Xue Wen-Bo Liu Engineering research center of Organosilicon Compounds&Materials(Ministry of education)and College of Chemistry and Molecular sciences Wuhan UniversityWuhanHubei430072 China

Comprehensive Summary,The azepine ring is a prominent structural scaffold in biologically significant molecules. In this study, we present a Ni(II)-catalyzed asymmetric difunctionalization of alkynes, involving intermolecular regioselective arylation and intramolecular nitrile addition, enabling the synthesis of enantioenriched azepine derivatives. This reaction simultaneously installs an all-carbon quaternary stereocenter and introduces an unprotected imine functionality, showing great promise for subsequent transformations. The reaction exhibits good tolerance toward various functional groups, resulting in high yields and enantioselectivities. The synthetic utility of this methodology is further demonstrated through gram-scale synthesis and product derivatization. This research offers an efficient approach to the synthesis of seven-membered nitrogen heterocycles.

关键词： Nickel Asymmetric catalysis N-Heterocycles Alkyne functionalization Quaternary centers

C_(Ar)-Br bond cleavage via cooperative EnT/NHC catalysis: mild access to indolines

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Science China Chemistry 2024年第3期67卷 922-927页

作者： Yi-Xiong Dong Cao-Bo Li Ming-Lei Jin Zhong-Hua Gao Song Ye Beijing National Laboratory for Molecular sciences CAS Key Laboratory of Molecular Recognition and FunctionCAS Research/Education Center for Excellence in Molecular SciencesInstitute of ChemistryChinese Academy of SciencesBeijing 100190China University of Chinese Academy of sciences Beijing 100049China

The cooperative visible-light mediated and NHC-catalyzed dearomative arylation-acylation of N-(2-bromobenzoyl)indoles with aldehydes was developed, affording the corresponding highly functionalized polycyclic indolines in moderate to good yields with exclusive diastereoselectivities. Mechanism investigations support the activation of CAr-Br bond via visible-light mediated energy transfer(EnT) and the following single-electron-transfer(SET) with Breslow intermediate under NHC catalysis to give key aryl radical and ketyl radical. This protocol demonstrates the cleavage of CAr-Br bond under mild cooperative EnT/NHC catalysis.

关键词： energy transfer N-heterocyclic carbenes photocatalysis aryl radicals indolines

A new scheme of climate-vegetation regionalization in the Hengduan Mountains Region

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Science China Earth sciences 2024年第3期67卷 751-768页

作者： Xueqin ZHANG Xiaoming XU Xiang LI Peng CUI Du ZHENG Key Laboratory of Land Surface Pattern and Simulation Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing 100101China University of Chinese Academy of sciences Beijing 100049China China-Pakistan Joint research center on Earth sciences Chinese Academy of Sciences-Higher Education Commission of PakistanIslamabad 45320Pakistan

The Hengduan Mountains Region(HMR) is essential for the future ecological protection, clean energy production,Sichuan-Xizang and Yunnan-Xizang railways, and other major infrastructure projects in China. The distributions of climate and vegetation exhibit significant regional differentiation and vertical zonality due to the rugged longitudinal ranges and gorges and the complex disaster-prone environments in HMR. Therefore, it is urgent to develop the climate-vegetation regionalization in HMR to effectively satisfy the national requirements such as agricultural production and ecological protection, mountain disaster risk prevention, and major project construction. We here develop a new scheme of climate-vegetation regionalization with the latest demarcation outcome of HMR, the ground observation from 122 meteorological stations in HMR and its surrounding areas during 1990–2019, and the high-precision remote sensing data of land cover types. The new scheme first constructs the regionalization index system, fully considering the extraordinarily complicated geomorphic pattern of mountains and valleys, the scarcity of meteorological observations, and the remarkable differentiation of climate and vegetation in HMR. The system consists of three primary regionalization indices(i.e., days with daily average temperature steady above 10°C, aridity index, and main vegetation types, dividing the temperature zones, moisture regions, and vegetation subregions, respectively) and three auxiliary indices of the accumulated temperature above 10°C, and the temperatures in January and July. Then, the HMR is divided into five temperature zones, 20 moisture regions, and 55 vegetation subregions. Compared with previous regionalization schemes, the new scheme optimizes the climate spatial interpolation model of thin plate smoothing spline suitable for the unique terrain in HMR. Moreover, the disputed division index threshold between different climatic zones(regions) is scientifically clarified using geographical detectors. Specifically, t

关键词： Climate-vegetation regionalization Thin plate smoothing spline(TPSS) GeoDetector Stepwise downscaling pane division method Hengduan Mountains Region

Deciphering resistancemechanisms and novel strategies to overcome drug resistance in ovarian cancer:a comprehensive review

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Oncology research 2024年第5期32卷 831-847页

作者： EFFAT ALEMZADEH LEILA ALLAHQOLI AFROOZ MAZIDIMORADI ESMAT ALEMZADEH FAHIMEH GHASEMI HAMID SALEHINIYA IBRAHIM ALKATOUT Infectious Diseases research center Birjand University of Medical SciencesBirjandIran Department of Midwifery Ministry of Health and Medical EducationTehranIran Student research Committee Shiraz University of Medical SciencesShirazIran Department of Biotechnology Faculty of MedicineBirjand University of Medical SciencesBirjandIran Cellular and Molecular research center Birjand University of Medical SciencesBirjandIran Social Determinants of Health research center Birjand University of Medical SciencesBirjandIran Kiel School of Gynaecological Endoscopy Campus KielUniversity Hospitals Schleswig-HolsteinKielGermany

Ovarian cancer is among the most lethal gynecological cancers,primarily due to the lack of specific symptoms leading to an advanced-stage diagnosis and resistance to chemotherapy.Drug resistance(DR)poses the most significant challenge in treating patients with existing drugs.The Food and Drug Administration(FDA)has recently approved three new therapeutic drugs,including two poly(ADP-ribose)polymerase(PARP)inhibitors(olaparib and niraparib)and one vascular endothelial growth factor(VEGF)inhibitor(bevacizumab)for maintenance therapy.However,resistance to these new drugs has emerged.Therefore,understanding the mechanisms of DR and exploring new approaches to overcome them is crucial for effective management.In this review,we summarize the major molecular mechanisms of DR and discuss novel strategies to combat DR.

关键词： Chemotherapy Drug resistance mechanisms Ovarian cancer PARP inhibitors VEGF inhibitor

Solid-state lithium-ion batteries for grid energy storage:opportunities and challenges

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Science China Chemistry 2024年第1期67卷 43-66页

作者： Xin Chang Yu-Ming Zhao Boheng Yuan Min Fan Qinghai Meng Yu-Guo Guo Li-Jun Wan CAS Key Laboratory of Molecular Nanostructure and Nanotechnology CAS Research/Education Center for Excellence in Molecular SciencesBeijing National Laboratory for Molecular Sciences(BNLMS)Institute of ChemistryChinese Academy of Sciences(CAS)Beijing 100190China University of Chinese Academy of sciences Beijing 100049China

The energy crisis and environmental pollution drive more attention to the development and utilization of renewable energy.Considering the capricious nature of renewable energy resource,it has difficulty supplying electricity directly to consumers stably and efficiently,which calls for energy storage systems to collect energy and release electricity at peak periods.Due to their flexible power and energy,quick response,and high energy conversion efficiency,lithium-ion batteries stand out among multiple energy storage technologies and are rapidly deployed in the grid.Pursuing superior performance and ensuring the safety of energy storage systems,intrinsically safe solid-state electrolytes are expected as an ideal alternative to liquid electrolytes.In this review,we systematically evaluate the priorities and issues of traditional lithium-ion batteries in grid energy storage.Beyond lithium-ion batteries containing liquid electrolytes,solid-state lithium-ion batteries have the potential to play a more significant role in grid energy storage.The challenges of developing solid-state lithium-ion batteries,such as low ionic conductivity of the electrolyte,unstable electrode/electrolyte interface,and complicated fabrication process,are discussed in detail.Additionally,the safety of solid-state lithium-ion batteries is re-examined.Following the obtained insights,inspiring prospects for solid-state lithium-ion batteries in grid energy storage are depicted.

关键词： lithium-ion batteries grid energy storage solid-state electrolytes interface stability

Kinetic and mechanism of the reaction between Cl and several mono-methyl branched alkanes

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Journal of Environmental sciences 2024年第1期135卷 474-482页

作者： Yan Chen Weigang Wang Junling Li Li Zhou Bo Shi Cici Fan Ke Wang Hao Zhang Hong Li Maofa Ge State Key Laboratory for Structural Chemistry of Unstable and Stable Species Beijing National Laboratory for Molecular Sciences(BNLMS)CAS Research/Education Center for Excellence in Molecular SciencesInstitute of ChemistryChinese Academy of SciencesBeijing 100190China University of Chinese Academy of sciences Beijing 100049China State Key Laboratory of Environmental Criteria and Risk Assessment Chinese Research Academy of Environmental SciencesBeijing 100012China National Engineering research center for Flue Gas Desulfurization Department of Environmental Science and EngineeringSichuan UniversityChengdu 610065China College of Chemistry and Materials Science Hebei Normal UniversityShijiazhuang 050024China

Branched alkanes are ubiquitous in the troposphere and play an important role in the chemical processes.In this work,the rate constants and products for the reaction of Cl atoms with 3-methylhexane and 2-methylheptane were measured at room temperature(298±0.2K)and atmospheric pressure using a conventional relative rate method.The rate constants of 3-methylhexane and 2-methylheptane in units of cm~3/(mol·sec)are(3.09±0.31)×10^(-10)and(3.67±0.40)×10^(-10),respectively.Furthermore,the corresponding atmospheric lifetime of the studied branched alkanes with Cl was 6.92-89.90 hours and 5.82-75.69 hours,respectively.The estimated atmospheric lifetimes indicated that the reaction with Cl atoms could be the most important atmospheric degradation pathway for 3-methylhexane and2-methylheptane.Primary gas-phase products of the reactions were identified and quantified,and particle-phase products were also obtained.The atmosphere oxidation mechanism of Cl atoms with 3-methylhexane and 2-methylheptane is proposed.The SOA yields of 3-methylhexane and 2-methylheptane from the reaction of Cl atoms were determined to be7.96%±0.89%and 13.35%±1.50%respectively.Overall,the results reveal that the primary loss process of branched alkanes is the reaction with Cl atoms,which impacts its degradation on a regional scale.

关键词： 3-Methylhexane 2-Methylheptane Chlorine atoms Kinetics Mechanism

Time-lagged Effects of the Spring Atmospheric Heat Source over the Tibetan Plateau on Summer Precipitation in Northeast China during 1961–2020:Role of Soil Moisture

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Advances in Atmospheric sciences 2024年第8期41卷 1527-1538页

作者： Yizhe HAN Dabang JIANG Dong SI Yaoming MA Weiqiang MA Institute of Atmospheric Physics Chinese Academy of Sciences State Key Laboratory of Tibetan Plateau Earth System Environment and Resources (TPESER)Institute of Tibetan Plateau Research Chinese Academy of Sciences National Institute of Natural Hazards Ministry of Emergency Management of China University of Chinese Academy of sciences College of Atmospheric sciences Lanzhou University National Observation and research Station for Qomolongma Special Atmospheric Processes and Environmental Changes Kathmandu center of research and education Chinese Academy of Sciences China-Pakistan Joint research center on Earth sciences Chinese Academy of Sciences

The spring atmospheric heat source(AHS) over the Tibetan Plateau(TP) has been suggested to affect the Asian summer monsoon and summer precipitation over South China. However, its influence on the summer precipitation in Northeast China(NEC) remains unknown. The connection between spring TP AHS and subsequent summer precipitation over NEC from 1961 to 2020 is analyzed in this study. Results illustrate that stronger spring TP AHS can enhance subsequent summer NEC precipitation, and higher soil moisture in the Yellow River Valley-North China region(YRVNC)acts as a bridge. During spring, the strong TP AHS could strengthen the transportation of water vapor to East China and lead to excessive rainfall in the YRVNC. Thus, soil moisture increases, which regulates local thermal conditions by decreasing local surface skin temperature and sensible heat. Owing to the memory of soil moisture, the lower spring sensible heat over the YRVNC can last until mid-summer, decrease the land–sea thermal contrast, and weaken the southerly winds over the East Asia–western Pacific region and convective activities over the South China Sea and tropical western Pacific. This modulates the East Asia–Pacific teleconnection pattern, which leads to a cyclonic anomaly and excessive summer precipitation over NEC.

关键词： atmospheric heat source Northeast China soil moisture summer precipitation Tibetan Plateau