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Rapid and chemoselective imidation of sulfides in aqueous buffer enabled by a novel guanidine-derived N-O reagent

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Science China Chemistry 2024年第6期67卷 1929-1934页

作者： Hanzheng li Long xu Jiajia Dong Key Laboratory of Organofluorine Chemistry Center for Excellence in Molecular SynthesisShanghai Institute of Organic ChemistryUniversity of Chinese Academy of SciencesChinese Academy of SciencesShanghai200032China Institute of Translational Medicine National Facility for Translational Medicine(Shanghai)Shanghai Jiao Tong UniversityShanghai200240China School of Chemistry and Chemical Engineering Zhangjiang Institute for Advanced StudyShanghai Jiao Tong UniversityShanghai200240China Shanghai Artificial Intelligence Laboratory Shanghai200232China

Herein we report the facile synthesis of a series of novel N-O reagents and identify N′-di-Boc-N′′-[(mesitylsulfonyl)oxy]-guanidine as an efficient imidating *** reagent is synthetically scalable and bench-stable,yet it shows unprecedented reactivity and chemoselectivity towards S(II)in buffer/hexafluoroisopropanol(HFIP)system,to generate a new class of Nguanyl *** transformation of N-guanyl sulfilimines to N-guanyl sulfoximines provides us a chance to investigate these rarely reached compounds,which are shown to be versatile precursors to a variety of N-heterocyclic and *** work provides an addition to the tool box of both sulfur imidation and guanidine synthesis,especially for the need of rapid and selective modifications of sulfur(II)center under biocompatible conditions.

关键词： sulfur imidation N-O reagent

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Analysis on characteristics of extreme precipitation indices and atmospheric circulation in Northern Shanxi

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Research in Cold and Arid Regions 2024年第2期16卷 84-97页

作者： Xia cai Yan Song lin cai Xin Su GuiHua liang YanMing xu Shuozhou Meteorological Bureau of Shanxi Province ShuozhouShanxi 036002China China Meteorological Administration Training Center Beijing 100081China Heze University of Shandong Province HezeShandong 274000China Huafeng Meteorological Media Group Beijing 100081China Shuocheng Meteorological Bureau ShuozhouShanxi 036002China

This article utilizes daily precipitation data from 28 national meteorological stations in northern Shanxi Province spanning from 1972 to 2020,and the US NCEP/NCAR monthly average reanalysis and ERA5 monthly average reanalysis *** study employs techniques such as empirical orthogonal function(EOF)decomposition,MannKendall mutation and other methods to investigate the spatiotemporal distribution of extreme precipitation index in northern Shanxi and their correlation with atmospheric *** research results show that:the absolute index,relative index,intensity index and sustained dry period index(CDD)in the continuous index appear from southwest to *** spatial distribution characteristics of the central region decrease,while the continuous wet period(CWD)decreases from the central to the east and *** three indices Rx1day,Rx5day,and CWD mutated in 1978,1975,and 1983 respectively,and other extreme precipitation indices all appeared in a sudden change from a low-value period to a high-value period occurred around *** the high-value years of the summer extreme precipitation index,there is a significant negative anomaly in the height field in the mid-high latitude regions of *** Shanxi is controlled by a broad low-pressure trough in the Lake Baikal *** vapor transported via the east,west,and south routes converges in the northern Shanxi region and encounters cold air from the *** is a strong upward motion anomaly at 500 hPa in the troposphere,and the dynamic conditions of upper-level divergence and lower-level convergence lead to more summer extreme precipitation in the northern Shanxi ***,in the low-value years of the summer extreme precipitation index,northern Shanxi is affected by a strong high-pressure ridge north of Lake *** is a downward motion anomaly at 500 hPa,and the northern Shanxi region lacks water *** cold and warm air cannot converge,and both the water vapor conditions

关键词： Northern Shanxi Extreme precipitation indices Spatio-temporal distribution and evolution Mutations Atmospheric circulation anomaly

Decoding aging: examining the non-evolutionary event from an evolutionary perspective

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Science China life Sciences 2024年第9期67卷 2026-2029页

作者： Yannan Guo Kang xu Jianping cai Zhao Wang Protein Science Key Laboratory of the Ministry of Education School of Pharmaceutical Sciences Tsinghua University Beijing Institute of Geriatrics Beijing HospitalNational Center of Gerontology National Health Commission

In an era marked by increased longevity,a deeper understanding of the older population is vital. By introducing an overlooked evolutionary perspective on aging, this article challenges traditional biogerontology, which primarily focuses on biological and clinical aspects. It articulately differentiates between chronological and physiological aging, suggesting that aging is an evolutionary byproduct rather than a direct evolutionary event.

关键词： liFE

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Efficacy and Safety of Chinese Herbal Medicines Combined with Chemical Drugs for Alzheimer's Disease:A Systematic Review and Meta-Analysis

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World Journal of Traditional Chinese Medicine 2024年第1期10卷 1-13页

作者： li xu Wen-Jun Chen cai-Jun Tian Yan Zhang Yan Ma Tian-Hao li Hong-Jie liu Zhe Zhang Department of the First College English College of Foreign LanguageShandong University of Traditional Chinese MedicineJinanChina Department of Oncology Linyi People's HospitalLinyiChina Department of Internal Medicine of Traditional Chinese Medicine The First Clinical CollegeShandong University of Traditional Chinese MedicineJinanChina Department of Chinese Materia Medica College of Traditional Chinese MedicineShandong University of Traditional Chinese MedicineJinanChina Department of Medicinal Chemistry College of PharmacyShandong University of Traditional Chinese MedicineJinanChina Community Healthcare Center Shenzhen Traditional Chinese Medicine HospitalShenzhenChina Department of Fundamentals of Traditional Chinese Medicine School of Traditional Chinese MedicineJinan UniversityGuangzhouChina Shandong Co-Innovation Center of Classic TCM Formula College of Traditional Chinese MedicineShandong University of Traditional Chinese MedicineJinanChina

Objective:To evaluate the efficacy and safety of Chinese herbal medicines(CHMs)combined with chemical drugs for the treatment of Alzheimer's disease(AD).Materials and Methods:Databases were searched to retrieve randomized controlled trials(RCTs)of CHMs combined with tacrine,galantamine,rivastigmine,donepezil,or memantine,following strict inclusion and exclusion *** research papers published in English,Chinese,and Japanese were *** primary outcome was the mini-mental state examination(MMSE)score and the secondary outcomes were AD assessment scale cognitive subscale(ADAS-Cog)score and safety ***-analysis was carried out using Rev Man 5.3 and subgroup analysis was conducted to identify the sources of ***:A total of 15 RCTs with 1386 participants were included in this *** donepezil was used in the retrieved ***-analyses showed that the combination of CHMs with donepezil led to significant improvement in the MMSE score(Z=9.45;Plieved adverse events such as insomnia(risk ratio[RR]=0.20,95%CI:0.06-0.68;P=0.01)and hive(RR=0.10;95%CI:0.01-0.73;P=0.02).Conclusions:The combination of CHMs with a chemical drug like donepezil led to significant improvements in patient cognition as well as a better safety profile when compared to the application of a chemical drug alone.

关键词： Alzheimer's disease Chinese herbal medicine donepezil memantine meta-analysis randomized controlled trials rivastigmine

Biomass-based materials for advanced supercapacitor:principles,progress,and perspectives

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Aggregate 2024年第1期5卷 95-114页

作者： Yaxuan Wang Ting xu Kun liu Meng Zhang xu-Min cai Chuanling Si State Key Laboratory of Biobased Fiber Manufacturing Technology Tianjin Key Laboratory of Pulp and PaperTianjin University of Science and TechnologyTianjinChina Jiangsu Co-Innovation Center of Efficient Processing and Utilization of Forest Resources College of Chemical EngineeringNanjing Forestry UniversityNanjingChina

Supercapacitors exhibit considerable potential as energy storage devices due to their high power density,fast charging and discharging abilities,long cycle life,and *** the increasing environmental concerns associated with synthetic compounds,the use of environment friendly biopolymers to replace conventional petroleum-based materials has been widely ***-based materials are biodegradable,renewable,environment friendly and *** unique hierarchical nanostructure,excellent mechanical properties and hydrophilicity allow them to be used to create functional conductive materials with precisely controlled structures and different *** this review,the latest development of biomass-based supercapacitor materials is reviewed and *** paper describes the physical and chemical properties of various biopolymers and their impact on supercapacitors,as well as the classification and basic principles of ***,a comprehensive discussion is presented on the utilization of biomass-based materials in supercapacitors and their recent applications across a range of supercapacitor ***,an overview of the future prospects and challenges pertaining to the utilization of biomass-based materials in supercapacitors is provided.

关键词： biomass electrodes electrolyte energy storage supercapacitor

Magnetic and luminescent properties of bifunctional composite Fe_(3)O_(4)@Y_(2)O_(2)S:Eu^(3+)

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Journal of Rare Earths 2024年第8期42卷 1568-1576,I0006页

作者： Zhiqi liang Zhili Zhang liu li Wen xu Decai li School of Mechanical Electronic and Control EngineeringBeijing Jiaotong UniversityBeijing100044China Beijing Key Laboratory of Flow and Heat Transfer of Phase Changing in Micro and Small Scale Beijing100044China State Key Laboratory of Tribology Tsinghua UniversityBeijing100084China

As a kind of non-destructive testing method,magnetic particle inspection is widely used in the fields of aviation and high-speed *** properties of magnetic fluorescent bifunctional composites,such as fluorescence intensity and magnetic properties,have increasing demands in magnetic particle *** earth compounds offer potential as novel materials for fluorescent magnetic bifunctional composites due to their excellent optical properties and extremely narrow emission *** this work,the rare earth fluorescent material Y_(2)O_(2)S:Eu^(3+) was synthesized by solid-state reaction ***_(3)O_(4)nanoparticles prepared by hydrothermal method were uniformly coated on the Y_(2)O_(2)S:Eu^(3+) particles through physical adsorption of *** obtained Fe_(3)O_(4)@Y_(2)O_(2)S:Eu^(3+) exhibits dark red color under the ultraviolet *** additio n,X-ray diffractio n,morphology,photoluminescence and hyste resis loop of Fe_(3)O_(4)@Y_(2)O_(2)S:Cu^(3+) were *** luminescence mechanism of Y_(2)O_(2)S:Eu^(3+) is described in detail Fe_(3)O_(4)@Y_(2)O_(2)S:Cu^(3+) displays good paramagnetism and has a good controllability under a magnetic *** magnetic particle inspection of Fe_(3)O_(4)@Y_(2)O_(2)S:Eu^(3+) was performed using a 4-pole electromagnet and a test piece *** magnetic fluorescent bifunctional composite presented in this work can be applied for non-destructive testing.

关键词： Bifunctional material Fe_(3)O_(4) Y_(2)O_(2)S:Eu^(3+) Luminescence Solid-state reaction Rare earths

Perception of fundamental science to boost lithium metal anodes toward practical application

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Green Energy & Environment 2024年第3期9卷 454-472页

作者： Jinkun Wang li Wang Hong xu li Sheng Xiangming He Institute of Nuclear and New Energy Technology Tsinghua UniversityBeijing100084China

As a key material for lithium metal batteries(LMBs),lithium metal is one of the most promising anode materials to break the bottleneck of battery energy density and a commonly used active material for reference *** lithium anodes are regarded as the holy grail of lithium batteries,decades of exploration have not led to the successful commercialization of LMBs,due mainly to the challenges related to the inherent properties of lithium *** pave the way for further investigation,herein,a comprehensive review focusing on the fundamental science of lithium are ***,the natures of lithium atoms and their isotopes,lithium clusters and lithium crystals are revisited,especially their structural and energetic ***,the electrochemical properties of lithium metal are *** important concepts and scientific questions,including the electronic structure of lithium,influence of high pressure and low temperature on the properties of lithium,factors influencing lithium deposition,generation of lithium dendrites,and electrode potential of lithium in different electrolytes,are explained and analyzed in *** to improve the performance of lithium anodes and thoughtfulness about the electrode potential in lithium battery research are proposed.

关键词： lithium Cluster Crystal Physicochemical property Fundamental science

Aerodynamic Performance of Three Flapping Wings with Unequal Spacing in Tandem Formation

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Journal of Bionic Engineering 2024年第4期21卷 1662-1676页

作者： Min Chang Ziyi xu Zengshuang Chen li li xueguang Meng Unmanned System Research Institute National Key Laboratory of Unmanned Aerial Vehicle TechnologyNorthwestern Polytechnical UniversityXi’an710072People’s Republic of China State Key Laboratory for Strength and Vibration of Mechanical Structures School of Aerospace EngineeringXi’an Jiaotong UniversityXi’an710049People’s Republic of China Xi’an Aeronautics Computing Technique Research Institute Aviation Industry Corporation of ChinaXi’an710076People’s Republic of China

To better understand the aerodynamic reasons for highly organized movements of flying organisms,the three-flapping wing system in tandem formation was studied numerically in this *** from previous relevant studies on the multiple flapping wings that are equally spaced,this study emphasizes the impact of unequal spacing between individuals on the aerodynamics of each individual wing as well as the whole *** is found that swapping the distance between the first and second wing with the distance between the second wing and the rearmost wing does not affect the overall aerodynamic performance,but significantly changes the distribution of aerodynamic benefits across each *** the whole flapping cycle,three effects are at *** narrow channel effect and the downwash effect can promote and weaken the wing lift,respectively,while the wake capture effect can boost the *** also shows that these effects could be manipulated by changing the spacing between adjacent *** findings provide a novel way for flow control in tandem formation flight and are also inspiring for designing the formation flight of bionic aircraft.

关键词： Three flapping wings Unequal spacing Aerodynamic performance Tandem formation

Altered oceanic crust source for the alkaline rocks with superchondritic Nb/Ta ratios due to the steep subduction

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Journal of Earth Science 2024年

作者： xu Zhao Ning-Bo li He-cai Niu Shu-Cheng Tan Department of Geology， School of Earth Sciences， Yunnan University CAS Key Laboratory of Mineralogy and Metallogeny， Guangzhou Institute of Geochemistry， Chinese Academy of Sciences CAS Center for Excellence in Deep Earth Science

The cause resulting in alkaline rocks with superchondritic Nb/Ta ratios remains a geochemical enigma. This paper present zircon and apatite geochronology， mineralogy， geochemistry， and Nd-Hf-Zn isotope investigation on the Ejinao nepheline syenite from South China to constrain the petrogenesis of alkaline rocks. The occurrence of alkaline minerals， including alkaline feldspar， arfvedsonite， and nepheline， indicate an alkaline feature of the Ejinao nepheline syenite. Zircon and apatite from the rock show U-Pb concordia age of 135.4±0.9 Ma and 137.5±5.8Ma， respectively， suggesting generation in the Early Cretaceous. The rock is characterized by low MgO （0.17 wt.%–0.26 wt.%） contents， but high Fe2O3T（4.66 wt.%–6.16 wt.%） and total alkalis (Na2O + K2O = 12.1 wt.%–13.1 wt.%) contents， consistent with the melts from subducting oceanic crust rather than mantle peridotite. The rock has low TiO2（0.13 wt.%–0.21 wt.%） contents and superchondritic Nb/Ta and Zr/Hf ratios， resulting from rutile residue in the source area. The εNd（t）（-1.35 to -1.09）， εHf（t）（-3.03 to -1.52）， and δ66Zn （0.32‰ to 0.34‰） values of the nepheline syenite manifest the involvement of 15%–20% carbonate-bearing sediments in the altered oceanic crust. Geochemical modeling further reveals that the nepheline syenite was sourced from 10%–20% melting of such a source. This superchondritic Nb/Ta nepheline syenite was generated during the steep subduction of the Paleo-Pacific Ocean， which is needed to bring oceanic slab to a hot mantle and resulted in the altered oceanic crust melting. Our study highlights that the altered oceanic crust represents a novel source for superchondritic Nb/Ta alkaline rocks.

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