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Recent advances of versatile reagents as controllable building blocks in organic synthesis

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chinese chemical Letters 2024年第2期35卷 24-43页

作者： Shaomin chen Luigi Vaccaro Yanlong Gu Key Laboratory of Material chemistry for Energy conversion and Storage Ministry of EducationHubei Key Laboratory of Material Chemistry and Service FailureSchool of Chemistry and Chemical EngineeringHuazhong University of Science and TechnologyWuhan 430074China Laboratory of Green S.O.c. Dipartimento di ChimicaBiologia e BiotecnologieUniversità degli Studi di PerugiaVia Elce di Sotto 8Perugia 06123Italy School of chemistry and chemical Engineering The Key Laboratory for Green Processing of Chemical Engineering of Xinjiang BingtuanShihezi UniversityShihezi 832004China

Diversity-oriented synthesis is a powerful and interesting synthetic tool for the rapid construction of structurally complex and privileged scaffolds from readily accessible starting *** date,diversity-oriented synthesis mostly relies on the employment of versatile *** reagents can be regulated as controllable and flexible building blocks for multipurpose *** the past decade,a variety of multifunctional reagents have been ***,most versatile reagents usually need multi-step synthesis,thus restricting their wide application to a large *** terms of the practicalities and universalities,we prefer to pay more attention to the utilization of simple and practical versatile reagents with multiple reactivities,mainly including atropaldehyde acetals,aryl methyl ketones,vinylene carbonate,vinyl azides,aryldiazonium salts,rongalite,halodifluoromethyl *** importantly,these versatile reagents can also play different roles simultaneously in the same reaction,in which their different reactivities are converged into the final target *** strategy can not only offer more possibilities for the synthesis of several active pharmaceutical ingredients,but also minimize the occurrence of some side reactions by lessening the varieties of ***,a perspective is given at the end of this review.

关键词： Versatile reagents Divergent synthesis Dual synthons Bond cleavage Tandem reactions

Toward Trustworthy Decision-Making for Autonomous Vehicles:A Robust Reinforcement Learning Approach with Safety Guarantees

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Engineering 2024年第2期33卷 77-89页

作者： Xiangkun He Wenhui Huang chen Lv School of Mechanical and Aerospace Engineering Nanyang Technological UniversitySingapore 639798Singapore

While autonomous vehicles are vital components of intelligent transportation systems,ensuring the trustworthiness of decision-making remains a substantial challenge in realizing autonomous ***,we present a novel robust reinforcement learning approach with safety guarantees to attain trustworthy decision-making for autonomous *** proposed technique ensures decision trustworthiness in terms of policy robustness and collision ***,an adversary model is learned online to simulate the worst-case uncertainty by approximating the optimal adversarial perturbations on the observed states and environmental *** addition,an adversarial robust actor-critic algorithm is developed to enable the agent to learn robust policies against perturbations in observations and ***,we devise a safety mask to guarantee the collision safety of the autonomous driving agent during both the training and testing processes using an interpretable knowledge model known as the Responsibility-Sensitive Safety ***,the proposed approach is evaluated through both simulations and *** results indicate that the autonomous driving agent can make trustworthy decisions and drastically reduce the number of collisions through robust safety policies.

关键词： Autonomous vehicle Decision-making Reinforcement learning Adversarial attack Safety guarantee

Elevational patterns of warming effects on plant community and topsoil properties: focus on subalpine meadows ecosystem

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Journal of Mountain Science 2024年第1期21卷 146-159页

作者： HAO Aihua LUO Zhengming chen Xiaojiang Department of Geography Xinzhou Normal UniversityXinzhou 034000China Department of Biological Sciences Xinzhou Normal UniversityXinzhou 034000China

climate warming profoundly affects plant biodiversity, community productivity, and soil properties in alpine and subalpine grassland ecosystems. However, these effects are poorly understood across elevational gradients in subalpine meadow ecosystems. To reveal the elevational patterns of warming effects on plant biodiversity, community structure, productivity, and soil properties, we conducted a warming experiment using open-top chambers from August 2019 to August 2022 at high(2764 m a. s. l.), medium(2631 m a. s. l.), and low(2544 m a. s. l.) elevational gradients on a subalpine meadow slope of Mount Wutai, Northern china. Our results showed that three years of warming significantly increased topsoil temperature but significantly decreased topsoil moisture at all elevations(Pcentage of increasing temperature and decreasing moisture both gradually raised with elevation lifting. Warming-induced decreasing proportions of soil organic carbon(SOc, by 19.24%), and total nitrogen(TN, by 24.56%) were the greatest at high elevational gradients. Experimental warming did not affect topsoil c: N, p H, NO_(3)^(-)-N, or NH_(4)^(+)-N at the three elevational gradients. Warming significantly increased species richness(Pcantly decreased belowground biomass(Pcm at three elevational gradients. Warming caused significant increases in the aboveground biomass in the three elevational plots. Warming significantly increased the aboveground biomass of graminoids in medium(by 92.47%) and low(by 98.25%) elevational gradients, that of sedges in high(by 72.44%) and medium(by 57.16%) elevational plots, and that of forbs in high(by 75.88%), medium(by 34.38%), and low(by 74.95%) elevational plots. Species richness had significant linear correlations with SOc, TN, and c: N(Pcant nonlinear responses to soil temperature and soil moisture in the warmed treatm

关键词： Warming effect Plant diversity pattern community structure change Elevation gradient Alpine meadow ecosystem Mount Wutai

Unveiling the secrets of diatom-mediated calcification: Implications for the biological pump

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Science china Earth Sciences 2024年第9期67卷 2895-2909页

作者： Yiwen PAN Yifan LI chen-Tung Arthur chen Zong-Pei JIANG Wei-Jun cAI Yunwen SHEN Zesheng DING Qixian chen Yanan DI Wei FAN chenba ZHU Ying chen Ocean college Zhejiang University Hainan Institute of Zhejiang University Department of Oceanography Sun Yat-Sen University School of Marine Science and Policy University of Delaware carbon Neutral Innovation Research center Xiamen University

Siliceous diatoms are one of the most prominent actors in the oceans, and they account for approximately 40% of the primary production and particulate organic carbon export flux. It is believed that changes in carbon flux caused by variations in diatom distribution can lead to significant climate shifts. Although the fundamental pathways of diatom-driven carbon sequestration have long been established, there are no reports of cacO3precipitation induced by marine diatom species. This manuscript introduces novel details regarding the enhancement of aragonite precipitation during photosynthesis in Skeletonema costatum in both artificial and natural seawater. Through direct measurements of cell surfaces via a pH microelectrode and zeta potential analyzer, it was determined that the diatom-mediated promotion of cacO3precipitation is achieved through the creation of specific microenvironments with concentrated [cO32–] and [ca2+] and/or the dehydrating effect of adsorbed ca2+.Based on this mechanism, it is highly plausible that diatom-mediated calcification could occur in the oceans, an assertion that was supported by the significant deviation of total alkalinity（TA） from the conservative TA-salinity mixing line during a Skeletonema costatum bloom in the East china Sea and other similar occurrences. The newly discovered calcification pathway establishes a link between particulate inorganic and organic carbon flux and thus helps in the reassessment of marine carbon export fluxes and cO2sequestration efficiency. This discovery may have important ramifications for assessing marine carbon cycling and predicting the potential effects of future ocean acidification.

关键词： Diatom bloom Skeletonema costatum calcification Biological carbon pump counter carbonate pump

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Hydrogen-rich water alleviates constipation by attenuating oxidative stress through the sirtuin1/nuclear factor-erythroid-2-related factor 2/heme oxygenase-1 signaling pathway

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World Journal of Gastroenterology 2024年第20期30卷 2709-2725页

作者： Kai-Di chen Kui-Ling Wang chen chen Yi-Jia Zhu Wen-Wen Tang Yu-Ji Wang Ze-Peng chen Lin-Hai He Yu-Gen chen Wei Zhang Jiangsu Province Hospital of chinese Medicine The Affiliated Hospital of Nanjing University of Chinese MedicineNanjing 210029Jiangsu ProvinceChina The No.1 clinical Medical college Nanjing University of Chinese MedicineNanjing 210029Jiangsu ProvinceChina Department of colorectal Surgery Jiangsu Province Hospital of Chinese MedicineThe Affiliated Hospital of Nanjing University of Chinese MedicineNanjing 210029Jiangsu ProvinceChina Jiangsu Province Key Laboratory of Tumor Systems Biology and chinese Medicine The Affiliated Hospital of Nanjing University of Chinese MedicineNanjing 210029Jiangsu ProvinceChina Jiangsu collaborative Innovation center of chinese Medicine in Prevention and Treatment of Tumor The Affiliated Hospital of Nanjing University of Chinese MedicineNanjing 210029Jiangsu ProvinceChina

BAcKGROUND constipation,a highly prevalent functional gastrointestinal disorder,induces a significant burden on the quality of patients'life and is associated with substantial healthcare ***,identifying efficient therapeutic modalities for constipation is of paramount *** stress is a pivotal contributor to colonic dysmotility and is the underlying pathology responsible for constipation ***,we postulate that hydrogen therapy,an emerging and promising intervention,can serve as a safe and efficacious treatment for *** To determine whether hydrogen-rich water(HRW)alleviates constipation and its potential *** constipation models were established by orally loperamide to Sprague-Dawley *** freely consumed HRW,and were recorded their 24 h total stool weight,fecal water content,and charcoal propulsion *** samples were subjected to 16S rDNA gene *** non-targeted metabolomic analysis,malondialdehyde,and superoxide dismutase levels were *** tissues were stained with hematoxylin and eosin,Alcian blue-periodic acid-Schiff,reactive oxygen species(ROS)immunofluorescence,and immunohistochemistry for cell growth factor receptor kit(c-kit),PGP 9.5,sirtuin1(SIRT1),nuclear factor-erythroid-2-related factor 2(Nrf2),and heme oxygenase-1(HO-1).Quantitative real-time PcR and western blot analysis were conducted to determine the expression level of SIRT1,Nrf2 and HO-1.A rescue experiment was conducted by intraperitoneally injecting the SIRT1 inhibitor,EX527,into constipated ***460 cells were induced with H2O2 and treated with the metabolites to evaluate ROS and SIRT1 *** HRW alleviated constipation symptoms by improving the total amount of stool over 24 h,fecal water content,charcoal propulsion rate,thickness of the intestinal mucus layer,c-kit expression,and the number of intestinal *** modulated intestinal microbiota imbalance and abnormaliti

关键词： Hydrogen-rich water constipation Sirtuin1 Oxidative stress Gut microbiota Serum metabolites

Monothetic and conductive network and mechanical stress releasing layer on micron-silicon anode enabling high-energy solid-state battery

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Rare Metals 2024年第3期43卷 1017-1029页

作者： Xiang Han Min Xu Lan-Hui Gu chao-Fei Lan Min-Feng chen Jun-Jie Lu Bi-Fu Sheng Peng Wang Song-Yan chen Ji-Zhang chen college of Materials Science and Engineering Co-Innovation Center of Efficient Processing and Utilization of Forestry ResourcesNanjing Forestry UniversityNanjing210037China Department of Physics Xiamen UniversityXiamen361005China Western Digital corporation MilpitasCA95035USA

Silicon has ultrahigh capacity,dendrite-free alloy lithiation mechanism and low cost and has been regarded as a promising anode candidate for solid-state *** to the low infiltration of solid-state electrolyte(SSE),not the unstable solid-electrolyte interphase(SEI),but the huge stress during lithiation-and delithiation-induced particle fracture and conductivity lost tend to be the main *** this study,starting with micron-Si,a novel monothetic carbon conductive framework and a MgO coating layer are designed,which serve as electron pathway across the whole electrode and stress releasing layer,*** addition,the in situ reaction between Si and SSE helps to form a LiF-rich and mechanically stable SEI *** a result,the mechanical stability and charge transfer kinetics of the uniquely designed Si anode are significantly ***,high initial coulombic efficiency,high capacity and durable cycling stability can be achieved by applying the Si@MgO@c anode in *** example,high specific capacity of 3224.6 mAh·g^(-1)and long cycling durability of 200 cycles are *** work provides a new concept for designing alloy-type anode that combines surface coating on particle and electrode structure design.

关键词： Lithium-ion battery(LIB) Solid-state electrolyte(SSE) Silicon anode Stress relief coating

Presence of a long nuclear-localization signal sequence in homeodomain transcription factor Nkx 1.2

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Journal of Oceanology and Limnology 2024年第2期42卷 620-626页

作者： Xinyi LI Lihui chen Xinyuan WANG chen SUN Guangdong JI Guobin HU Zhenhui LIU college of Marine Life Science and Institute of Evolution&Marine Biodiversity Ocean University of ChinaQingdao 266003China Laoshan Laboratory Qingdao 266237China

Homeodomains,a 60-amino acid sequence encoded by 180 nucleotides,are highly conserved DNA-binding motifs that are present in a variety of transcription factors in species ranging from yeast to *** NKX proteins belong to the homeodomain(HD)-containing transcription factor *** play vital roles in the regulation of ***1-2 is one member of the NKX *** present,information about its nuclear localization signal(NLS)sequence is *** studied the NLS sequence of zebrafish Nkx1.2 by introducing sequence changes such as deletion,mutation,and truncation,and identified an NLS motif(QNRRTKWKKQ)that is localized at the c-terminus of the ***,the deletion of two amino acid residues(RR)in this NLS motif prevents Nkx1.2 from entering the nucleus,indicating that the two amino acids are essential for Nkx1.2 nuclear ***,the NLS motif alone is unable to target cytoplasmic protein glutathione S-transferase(GST)to the *** intact homeodomain is necessary for mediating the complete nuclear transport of cytoplasmic *** most nuclear import proteins with short NLS sequences,a long NLS is present in zebrafish *** also demonstrated that the sequences of homeodomain of NKX1.2 are well conserved among different *** study is informative to verify the function of the NKX1.2 protein.

关键词： NKX1.2 NKX protein homeodomain nuclear localization signal(NLS) nuclear transport

Durable Ru Nanocrystal with HfO_(2)Modification for Acidic Overall Water Splitting

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Nano-Micro Letters 2024年第9期16卷 462-477页

作者： Xiangkai Kong Jie Xu Zhicheng Ju changle chen School of Materials and Physics China University of Mining and TechnologyXuzhou 221116JiangsuPeople’s Republic of China Anhui Province Key Laboratory of Pollutant Sensitive Materials and Environmental Remediation Huaibei Normal UniversityHuaibei 235000AnhuiPeople’s Republic of China School of chemistry and Materials Science University of Science and Technology of ChinaHefei 230026AnhuiPeople’s Republic of China School of chemistry and chemical Engineering Nanjing UniversityNanjing 210023JiangsuPeople’s Republic of China

Durable and efficient bi-functional catalyst,that is capable of both oxygen evolution reaction and hydrogen evolution reaction under acidic condition,are highly desired for the commercialization of proton exchange membrane water ***,we report a robust L-Ru/HfO_(2)heterostructure constructed via confining crystalline Ru nanodomains by HfO_(2)*** assembled with a proton exchange membrane,the bi-functional L-Ru/HfO_(2)catalyst-based electrolyzer presents a voltage of 1.57 and 1.67 V to reach 100 and 300 mA cm^(-2)current density,prevailing most of previously reported Ru-based materials as well as commercial Pt/c||RuO_(2)*** is revealed that the synergistic effect of HfO_(2)modification and small crystalline domain formation significantly alleviates the over-oxidation of *** importantly,this synergistic effect facilitates a dual-site oxide path during the oxygen evolution procedure via optimization of the binding configurations of oxygenated *** a result,the Ru active sites maintain the metallic state along with reduced energy barrier for the rate-determining step(^(*)O→^(*)OOH).Both of water adsorption and dissociation(Volmer step)are strengthened,while a moderate hydrogen binding is achieved to accelerate the hydrogen desorption procedure(Tafel step).consequently,the activity and stability of acidic overall water splitting are simultaneously enhanced.

关键词： Ruthenium Hafnium dioxide Oxygen evolution catalysis Anti-oxidation

Enhanced properties of stone coal-based composite phase change materials for thermal energy storage

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International Journal of Minerals,Metallurgy and Materials 2024年第1期31卷 206-215页

作者： Baoshan Xie Huan Ma chuanchang Li Jian chen Key Laboratory of Renewable Energy Electric-Technology of Hunan Province School of Energy and Power EngineeringChangsha University of Science and TechnologyChangsha 410114China State Key Laboratory of Disaster Prevention and Reduction for Power Grid Changsha University of Science and TechnologyChangsha 410114China

Phase change materials (PcMs) can be incorporated with low-cost minerals to synthesize composites for thermal energy storage in building *** coal (Sc) after vanadium extraction treatment shows potential for secondary utilization in composite *** prepared Sc-based composite PcMs with Sc as a matrix,stearic acid (SA) as a PcM,and expanded graphite (EG) as an *** combined roasting and acid leaching treatment of raw Sc was conducted to understand the effect of vanadium extraction on promoting loading *** showed that the combined treatment of roasting at 900℃ and leaching increased the Sc loading of the composite by 6.2%by improving the specific surface *** loading capacity and thermal conductivity of the composite obviously increased by 127%and 48.19%,respectively,due to the contribution of 3wt% *** data were supported by the high load of 66.69%and thermal conductivity of 0.59 W·m^(-1)·K-1of the designed *** obtained composite exhibited a phase change temperature of 52.17℃,melting latent heat of 121.5 J·g^(-1),and good chemical *** Sc-based composite has prospects in building applications exploiting the secondary utilization of minerals.

关键词： thermal energy storage phase change material stone coal vanadium extraction secondary utilization