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Science China Chemistry 2024年第9期67卷 2982-2988页

作者： En-He Huang Li-Gao Liu You-Wei Yin Hao-Xuan Dong ji-jia Zhou Xin lu Bo Zhou Long-Wu Ye Key Laboratory for Chemical Biology of Fujian Province and State Key Laboratory of Physical Chemistry of Solid Surfaces College of Chemistry and Chemical Engineering Xiamen University State Key Laboratory of Organometallic Chemistry Shanghai Institute of Organic Chemistry Chinese Academy of Sciences

α-Imino metal carbenes are versatile intermediates in organic synthesis, and have broad applications in the assembly of divergent N-heterocycles. However, the catalytic enantioselective desymmetrization based on α-imino metal carbenes has not been developed to date. Herein, we disclose an enantioselective desymmetrizing C（sp2）–H functionalization of azide-ynamides via α-imino copper carbenes, leading to the efficient assembly of divergent chiral indoloazepines in generally moderate to excellent yields with high enantioselectivities. Notably, this reaction represents the first enantioselective desymmetrization based on α-imino metal carbenes. Further synthetic transformations and biological tests show the potential utility of this method. Moreover,computational studies are employed to elucidate the reaction mechanism and the origin of enantioselectivity.

关键词： enantioselective desymmetrization metal carbenes copper catalysis nitrene transfer alkynes

规划与规则的协同——国土空间详细规划制度建构方略

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城市规划 2024年第5期48卷 100-109页

作者：陈璐广州大学建筑与城市规划学院

城市规划起源于城市秩序失控问题,规划一直试图利用科学方法协调土地利用冲突、规范城市发展。通过分割还原来控制复杂性的经典科学方法已难以适应日益复杂的人居环境需求与全域用途管制的制度需求。为回归科学领域探讨规划与秩序的关系... 详细信息

城市规划起源于城市秩序失控问题,规划一直试图利用科学方法协调土地利用冲突、规范城市发展。通过分割还原来控制复杂性的经典科学方法已难以适应日益复杂的人居环境需求与全域用途管制的制度需求。为回归科学领域探讨规划与秩序的关系,本文以复杂系统科学为视角,梳理规划思想的转变趋势,通过分析两种秩序的形成及空间使用行为的复杂性,深入比较规划与规则的治理逻辑差异,提出规划与规则的协同治理逻辑:基于关系原则将已存在的一般规律规则化,作为维持秩序的底线性工具,协调行为与行为的关系;基于群体互动的详细规划过程将行为类型规则空间化,协调行为类型与空间类型的关系。通过详细规划的规则化转型,促进以人民为中心的自发秩序形成。

关键词：规划规则国土空间详细规划复杂系统科学治理逻辑

The occurrence,inheritance,and segregation of complex genomic structural variation in synthetic Brassica napus

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The Crop journal 2024年第2期12卷 515-528页

作者： Dandan Hu jin lu Wenwen Li Yinghui Yang junxiong Xu Han Qin Hao Wang Yan Niu Huaiqi Zhang Qingqing Liu Xiangxiang He Annaliese S.Mason jChris Pires Zhiyong Xiong jun Zou National Key Laboratory of Crop Genetic Improvement College of Plant Science and TechnologyHuazhong Agricultural UniversityWuhan 430070HubeiChina College of Agronomy Henan Agricultural UniversityZhengzhou 450002HenanChina Key Laboratory of Herbage and Endemic Crop Biotechnology Inner Mongolia UniversityHohhot 010070Inner MongoliaChina Plant Breeding Department University of BonnBonn 53115Germany Department of Soil and Crop Sciences Colorado State UniversityFort CollinsCO 80523USA

"Synthetic"allopolyploids recreated by interspecific hybridization play an important role in providing novel genomic variation for crop *** synthetic allopolyploids often undergo rapid genomic structural variation(SV).However,how such SV arises,is inherited and fixed,and how it affects important traits,has rarely been comprehensively and quantitively studied in advanced generation synthetic lines.A better understanding of these processes will aid breeders in knowing how to best utilize synthetic allopolyploids in breeding ***,we analyzed three genetic mapping populations(735 DH lines)derived from crosses between advanced synthetic and conventional Brassica napus(rapeseed)lines,using whole-genome sequencing to determine genome *** observed high tolerance of large structural variants,particularly toward the telomeres,and preferential selection for balanced homoeologous exchanges(duplication/deletion events between the A and C genomes resulting in retention of gene/chromosome dosage between homoeologous chromosome pairs),including stable events involving whole chromosomes("pseudoeuploidy").Given the experimental design(all three populations shared a common parent),we were able to observe that parental SV was regularly inherited,showed genetic hitchhiking effects on segregation,and was one of the major factors inducing adjacent novel and larger ***,novel SV occurred at low frequencies with no significant impacts on observed fertility and yield-related traits in the advanced generation synthetic ***,incorporating genome-wide SV in linkage mapping explained significantly more genetic variance for *** results provide a framework for detecting and understanding the occurrence and inheritance of genomic SV in breeding programs,and support the use of synthetic parents as an important source of novel trait variation.

关键词： Allopolyploid Large Genome structural variation Linkage mapping Synthetic polyploids Inheritance and segregation

One-step calcination synthesis of interface-coherent crystallized and surface-passivated LiNi_(0.5)Mn_(1.5)O_(4) for high-voltage lithium-ion battery

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Nano Research 2024年第5期17卷 4192-4202页

作者： Min Xu Bifu Sheng Yong Cheng junjie lu Minfeng Chen Peng Wang Bo Liu jizhang Chen Xiang Han Ming-Sheng Wang Siqi Shi College of Materials Science and Engineering Co-Innovation Center of Efficient Processing and Utilization of Forest ResourcesNanjing Forestry UniversityNanjing 210037China State Key Laboratory of Physical Chemistry of Solid Surfaces College of MaterialsXiamen UniversityXiamen 361005China College of Mathematics and Physics Jinggangshan UniversityJi’an 343009China School of Materials Science and Engineering Shanghai UniversityShanghai 200444China Western Digital Corporation 951 Sandisk DrMilpitasCA 95035USA

LiNi_(0.5)Mn_(1.5)O_(4)(LNMO)with a spinel crystal structure presents a compelling avenue towards the development of economic cobalt-free and high voltage(~5 V)lithium-ion ***,the elevated operational voltage of LNMO gives rise to pronounced interfacial interactions between the distorted surface lattices characterized by jahn-Teller(j-T)distortions and the electrolyte ***,a localized crystallized coherent LaNiO_(3) and surface passivated Li_(3)PO_(4) layer is deposited on LNMO via a one-step calcination *** evidenced by transmission electron microscopy(TEM),time-of-flight secondary ion mass spectrometry(ToF-SIMS)and density functional theory(DFT)calculation,the epitaxial growth of LaNiO_(3) along the LNMO lattice can effectively stabilize the structure and inhibit irreversible phase transitions,and the Li_(3)PO_(4) surface coating can prevent the chemical reaction between HF and transition metals without sacrificing the electrochemical *** addition,the ionic conductive Li_(3)PO_(4) and atomic wetting inter-layer enables fast charge transfer transport ***,the LNMO material enabled by the lattice bonding and surface passivating features,demonstrates high performance at high current densities and good capacity retention during long-term *** rational design of interface coherent engineering and surface coating layers of the LNMO cathode material offers a new perspective for the practical application of high-voltage lithium-ion batteries.

关键词： high-voltage cathode interface-coherent surface passivating electrochemical performance

Dinitrophenyl-oxadiazole compounds:Design strategy,synthesis,and properties of a series of new melt-cast explosives

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Defence Technology（防务技术） 2024年第5期35卷 100-107页

作者： Bao-long Kuang Ting-wei Wang Cong Li Mou Sun Qamar-un-Nisa Tariq Chao Zhang Zhi-ming Xie Zu-jia lu jian-guo Zhang State Key Laboratory of Explosion Science and Technology Beijing Institute of TechnologyBeijing100081China China Wuzhou Engineering Group CO. LTD.Beijing 100053China

Melt-cast explosives are the most widely used energetic materials in military composite explosives,researchers have been unremittingly exploring high-energy and insensitive melt-cast *** this work,a series of dinitrophenyl-oxadiazole compounds were designed and *** compounds have an ideal low melting point(80-97℃),good detonation performance(detonation velocity D=6455-6971 m/s,detonation pressure P=18-19 GPa)and extreme insensitive nature(impact sensitivity≥60 j,friction sensitivity>360 N).All these compounds were well characterized by nuclear magnetic resonance,fourier transform infrared spectroscopy,elemental *** 2,3 were unambiguously confirmed by X-ray single crystal diffraction *** a result,their overall properties are superior to traditional melt-cast explosives trinitrotoluene(TNT)and dinitroanisole(DNAN)which may have excellent potential applications in insensitive melt-cast explosives.

关键词： Dinitrophenyl-oxadiazole Melt-cast explosive Low sensitivity

Analysis of ancient mass extinction recoveries in marine environments: generating strategies for managing outcomes of the current mass extinction

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National Science Review 2024年第1期11卷 8-10页

作者： David j.Bottjer Department of Earth Sciences University of Southern California

The defining feature of a mass extinction and its associated recovery is the global amount of extinction that occurred[1]. However, there is finer-scale detail to the story, as seen in the ongoing modern mass extinction(the sixth mass extinction), which exhibits variable effects among marine ecosystems and environments, and hence geographic areas [1].

关键词：

Global weirding at mass extinction horizons

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National Science Review 2024年第1期11卷 10-12页

作者： Gregory j.Retallack Department of Earth Sciences University of Oregon

A strong motivation for studying mass extinctions is understanding how current climatic and biodiversity crises will affect creatures living on land such as ourselves. Perhaps the question is: how bad can it get? In that case, terrestrial Permian-Triassic mass extinctions are an irresistible worst-case scenario [1].

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Low-Energy Spin Excitations in Detwinned FeSe

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Chinese Physics Letters 2024年第6期41卷 112-118页

作者：刘瑞鲜 Mitsutaka Nakamura Kazuya Kamazawa 鲁兴业 Center for Advanced Quantum Studies School of Physics and AstronomyBeijing Normal UniversityBeijing 100875China j-PARC Center Japan Atomic Energy Agency(JAEA)TokaiIbaraki 319-1195Japan Research Center for Neutron Science and Technology Comprehensive Research Organization for Science and SocietyTokaiIbaraki 319-1106Japan

Antiferromagnetic spin fluctuation is regarded as the leading driving force for electron pairing in high-Tc *** iron-based superconductors,spin excitations at low energy range,especially the spin-resonance mode at ER~5kBTc,are important for understanding the ***,we use inelastic neutron scattering(INS)to investigate the symmetry and in-plane wave-vector dependence of low-energy spin excitations in uniaxial-strain detwinned Fe *** low-energy spin excitations(E<10 meV)appear mainly at Q=(±1,0)in the superconducting state(T9K)and the nematic state(T90 K),confirming the constant C_(2) rotational symmetry and ruling out the C_(4) mode at E≈3 meV reported in a prior INS ***,our results reveal an isotropic spin resonance in the superconducting state,which is consistent with the s±wave pairing *** slightly higher energy,low-energy spin excitations become highly *** full width at half maximum of spin excitations is elongated along the transverse *** Q-space isotropic spin resonance and highly anisotropic low-energy spin excitations could arise from dyz intra-orbital selective Fermi surface nesting between the hole pocket aroundΓpoint and the electron pockets centered at MX point.

关键词： excitation symmetry slightly

Delayed plasticity during spherical nanoindentation of an iron-chromium-aluminum alloy:Effect of ferric ion irradiation

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journal of Materials Science & Technology 2023年第36期167卷 228-236页

作者： Y.Zhang C.W.Li j.L.jiang j.F.Gu H.Wang Y.D.jia G.Wang X.G.An Q.Wang j.lu Institute of Materials Shanghai UniversityShanghai 200072China School of Materials Science and Engineering Shanghai Jiao Tong UniversityShanghai 200240China Department of Mechanical Engineering City University of Hong KongKowloonSARChina Science and Technology on Reactor Fuel and Materials Laboratory Nuclear Power Institute of ChinaChengdu 610041China Interdisciplinary Materials Research Center Institute for Advanced StudyChengdu UniversityChengdu610106China

Spherical nanoindentation of an iron-chromium-aluminum alloy was conducted to study the effect of ferric-ion(Fe 3+)irradiation on the time-dependent plasticity behavior in the surface layers of this *** was observed that the initiation of plasticity by the appearance of displacement burst or“pop-in”event occurred after a period of waiting time in the apparent elastic regime and that Fe^(3+)irradiation at 360°C and up to∼0.5 displacements per atom could make it happen under the lower applied loads but with a reduced *** the experimental data,an activation volume and activation energy were extracted for the delayed *** results show that Fe^(3+)-irradiation significantly reduced its acti-vation volume from∼3.05 b 3 to∼1.75 b 3(where b=Burgers vector),but slightly increased its activation energy from∼0.65 to∼0.71 *** the other hand,high-resolution scanning transmission electron mi-croscopy observations reveal that the irradiation at the elevated temperature created interstitial atom pair onto the(100)habit plane that can serve as the nucleation site of a100dislocation loop while elim-inating the pre-existing ***,it is indicated that heterogeneous nucleation of the dislocation loop was predominant in the delayed plasticity initiation of this alloy and that the nucleation of the interstitial-type dislocation loop was involved due to Fe^(3+)-irradiation.

关键词： Spherical nanoindentation Delayed plasticity FeCrAl alloy Fe^(3+)-irradiation

Computed tomography-based radiomics to predict early recurrence of hepatocellular carcinoma post-hepatectomy in patients background on cirrhosis

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World journal of Gastroenterology 2024年第15期30卷 2128-2142页

作者： Gui-Xiang Qian Zi-Ling Xu Yong-Hai Li jian-Lin lu Xiang-Yi Bu Ming-Tong Wei Wei-Dong jia Department of Hepatic Surgery Anhui Provincial HospitalThe First Affiliated Hospital of USTCDivision of Life Science and MedicineUniversity of Science and Technology of ChinaHefei 230001Anhui ProvinceChina Department of Hepatic Surgery Anhui Provincial Hospital Affiliated to Anhui Medical UniversityAnhui Medical UniversityHefei 230001Anhui ProvinceChina Department of Anorectal Surgery the First People’s Hospital of HefeiHefei 230001Anhui ProvinceChina

BACKGROUND The prognosis for hepatocellular carcinoma(HCC)in the presence of cirrhosis is unfavourable,primarily attributable to the high incidence of *** To develop a machine learning model for predicting early recurrence(ER)of posthepatectomy HCC in patients with cirrhosis and to stratify patients’overall survival(OS)based on the predicted risk of *** In this retrospective study,214 HCC patients with cirrhosis who underwent curative hepatectomy were *** feature selection was conducted using the least absolute shrinkage and selection operator and recursive feature elimination ***-radiologic features were selected through univariate and multivariate logistic regression *** machine learning methods were used for model comparison,aiming to identify the optimal *** model’s performance was evaluated using the receiver operating characteristic curve[area under the curve(AUC)],calibration,and decision curve ***,the Kaplan-Meier(K-M)curve was used to evaluate the stratification effect of the model on patient *** Within this study,the most effective predictive performance for ER of post-hepatectomy HCC in the background of cirrhosis was demonstrated by a model that integrated radiomics features and clinical-radiologic *** the training cohort,this model attained an AUC of 0.844,while in the validation cohort,it achieved a value of *** K-M curves illustrated that the combined model not only facilitated risk stratification but also exhibited significant discriminatory ability concerning patients’*** The combined model,integrating both radiomics and clinical-radiologic characteristics,exhibited excellent performance in HCC with *** K-M curves assessing OS revealed statistically significant differences.

关键词： Machine learning Radiomics Hepatocellular carcinoma Cirrhosis Early recurrence Overall survival Computed tomography Prognosis Risk factor Delta-radiomics