检索结果-南通市图书馆

Practical approach for detecting k-nonseparability of multipartite quantum states

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 32-48页

作者： Jie Guo Jinchuan Hou Xiaofei Qi Kan He College of Mathematics Taiyuan University of Technology School of Mathematics and Statistics Shanxi University key laboratory of Complex Systems and Data Science of Ministry of Education Shanxi University

The instantaneous detection of entanglement in quantum states poses a significant challenge in the fields of quantum computation and quantum information, and there are no practical methods or tools to complete this task satisfactorily so far. We propose a sufficient and necessary criterion of k-nonseparability for any n-partite finite or infinite dimensional systems, 2 ≤ k ≤ n. This criterion serves as the foundation for a practical scheme designed to detect entanglement and k-nonseparability across multipartite finite-dimensional systems. To exemplify the application of our scheme, we have developed a software tool that facilitates swift and precise identification of entanglement, k-nonseparability, and genuine entanglement within n-qubit systems, specifically tailored for systems with 2 ≤ n ≤ 4.

关键词： multipartite systems entanglement states entanglement witnesses ${\bm~k}$-nonseparability

Impregnating photo-stable gold precursor onto uncalcined TS-1 to boost catalytic hydro-oxidation of propane

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Science China Chemistry 2025年

作者： Zhihua Zhang Erchuan Yang Fan Liu Kesheng Xu Yuxia Zhong Jinwei Sun Shudong Shi Xuezhi Duan Xinggui Zhou State key laboratory of Chemical Engineering East China University of Science and Technology

Immobilizing highly dispersed Au nanoparticles onto titanium silicalite-1 (TS-1) by a simple impregnation method under light is still a challenging *** this work,a high photostable Au precursor protected by thiol ligands was firstly synthesized,and the as-prepared Au precursor displayed excellent stability under light for over 30 days,while the Au precursor without thiol ligands formed precipitates after just 2 h under ***,the Au precursor protected by thiol ligands was immobilized on the external surface of uncalcined TS-1 (i.e.,TS-1-B) by the incipient wetness impregnation method (IWI method) to prepare Au/TS-1-B *** activity of as-prepared Au/TS-1-B catalyst in the hydro-oxidation of propane to acetone was 1.4 times higher than that of the catalyst prepared by the deposition-precipitation urea method (DPU method).The structures of the Au/TS-1-B catalysts prepared by different methods were analyzed by multiple *** to the Au/TS-1-B catalyst prepared by the DPU method,the Au/TS-1-B catalyst synthesized by the IWI method exhibited a narrower size distribution of Au nanoparticles and had more small Au particles (<2 nm),which is the main reason for its superior ***,the effects of gold loadings,reaction temperature and Si/Ti molar ratio on the catalytic performance of the Au/TS-1-B catalyst prepared by the IWI method were also *** addition,the Au/TS-1-B catalyst prepared by the IWI method also exhibited excellent stability for over 140 h.

关键词：

Glucocorticoid receptor signaling in the brain and its involvement in cognitive function

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Neural Regeneration Research 2025年第9期20卷 2520-2537页

作者： Chonglin Su Taiqi Huang Meiyu Zhang Yanyu Zhang Yan Zeng Xingxing Chen Brain Science and Advanced technology Institute Hubei Province Key Laboratory of Occupational Hazard Identification and ControlSchool of MedicineWuhan University of Science and TechnologyWuhanHubei ProvinceChina

The hypothalamic-pituitary-adrenal axis regulates the secretion of glucoco rticoids in response to environmental *** the brain,a nuclear receptor transcription fa ctor,the glucocorticoid recepto r,is an important component of the hypothalamicpituitary-a d renal axis's negative feedback loop and plays a key role in regulating cognitive equilibrium and *** glucoco rticoid receptor influences cognitive processes,including glutamate neurotransmission,calcium signaling,and the activation of brain-derived neurotrophic factor-mediated pathways,through a combination of genomic and non-genomic *** interactions within the central nervous system can alter the expression and activity of the glucocorticoid receptor,there by affecting the hypothalamic-pituitary-a d renal axis and stress-related cognitive *** appropriate level of glucocorticoid receptor expression can improve cognitive function,while excessive glucocorticoid receptors or long-term exposure to glucoco rticoids may lead to cognitive *** with cognitive impairment-associated diseases,such as Alzheimer's disease,aging,depression,Parkinson's disease,Huntington's disease,stroke,and addiction,often present with dysregulation of the hypothalamic-pituitary-adrenal axis and glucocorticoid receptor *** review provides a comprehensive overview of the functions of the glucoco rticoid receptor in the hypothalamic-pituitary-a d renal axis and cognitive *** emphasizes that appropriate glucocorticoid receptor signaling fa cilitates learning and memory,while its dysregulation can lead to cognitive *** provides clues about how glucocorticoid receptor signaling can be targeted to ove rcome cognitive disability-related disorders.

关键词： brain-derived neurotrophic factor calcium signaling glucocorticoid receptor glucocorticoid glutamate transmission hypothalamic-pituitary-adrenal axis long-term potentiation neurocognitive disorders neuroplasticity stress

维普期刊数据库

Loss Aware Feature Attention Mechanism for Class and Feature Imbalance Issue

在线全文

学校读者我要写书评

暂无评论

Computers, Materials & Continua 2025年第1期82卷 751-775页

作者： Yuewei Wu Ruiling Fu Tongtong Xing Fulian Yin College of information and Communication Engineering Communication University of ChinaBeijing100024China State key laboratory of Media Convergence and Communication Communication University of ChinaBeijing100024China

In the Internet era,recommendation systems play a crucial role in helping users find relevant information from large *** imbalance is known to severely affect data quality,and therefore reduce the performance of recommendation *** to the imbalance,machine learning algorithms tend to classify inputs into the positive(majority)class every time to achieve high prediction *** can be categorized such as by features and classes,but most studies consider only class *** this paper,we propose a recommendation system that can integrate multiple networks to adapt to a large number of imbalanced features and can deal with highly skewed and imbalanced datasets through a loss *** propose a loss aware feature attention mechanism(LAFAM)to solve the issue of feature *** network incorporates an attention mechanism and uses multiple sub-networks to classify and learn *** better results,the network can learn the weights of sub-networks and assign higher weights to important *** propose suppression loss to address class imbalance,which favors negative loss by penalizing positive loss,and pays more attention to sample points near the decision *** on two large-scale datasets verify that the performance of the proposed system is greatly improved compared to baseline methods.

关键词： Imbalanced data deep learning e-commerce recommendation loss function big data analysis

Design high-performance narrowband emitters for blue light-emitting diodes through manipulating resonance structure of aromatic heterocycles

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Science China Chemistry 2025年

作者： Yue Yu Lei Xu Wenle Tan Yuyu Pan Jiyin Xiao Bohan Wang Guangjun Tian Yuguang Ma Lei Ying Institute of Polymer Optoelectronic Materials and Devices Guangdong Basic Research Center of Excellence for Energy and Information Polymer Materials State Key Laboratory of Luminescent Materials and Devices South China University of Technology School of Petrochemical Engineering Shenyang University of Technology key laboratory for Microstructural Material Physics of Hebei Province School of Science Yanshan University

Narrowband light-emitting materials play critical roles in improving the color gamut and energy consumption of electroluminescence. Herein we demonstrated that by regulating the ground state resonance structure form of emitters with polycyclic aromatic heterocycles, the high-energy vibration of the C–C bond can be effectively suppressed, resulting in narrow emission like classical cyanine dyes. The designed compounds consist of twist and planar conformation, while having differences in the orientation of the positioning electron-donating(nitrogen) and electron-accepting(carbonyl) groups in the polycyclic aromatic hydrocarbon skeleton. The resulting compound Ac-Ph-Ac with a dominated zwitterionic resonance structure exhibits a relatively wide electroluminescent profile with the full width at half maximum(FWHM) of 42 nm and moderate device performance. In contrast, the “soliton transition” of 2AcPh based on the cyanine limit character effectively suppresses C–C stretching vibration in the polycyclic aromatic heterocycle skeleton, leading to a narrow electroluminescent profile with FWHM of 30 nm(0.16 eV)associated with an impressively high external quantum efficiency of 28.52%, which is among the highest efficiencies of so far reported non-sensitized organic light-emitting diodes.

关键词：

Modeling and control of a rigid-flexible coupling robot for narrow space manipulations

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Science China Technological Sciences 2025年

作者： Kuangda CHEN Huan ZHAO Jiexin ZHANG Mei FENG Yiwei WANG Jinliang WANG Han DING State key laboratory of Intelligent Manufacturing Equipment and technology Huazhong University of Science and Technology key laboratory of CNC Equipment Reliability Ministry of Education Jilin University School of Medical Equipment Science and Engineering Huazhong University of Science and Technology

Narrow space manipulations are crucial for equipment maintenance, as they eliminate the need for disassembly, thus reducing costs and increasing efficiency. Cable-driven flexible robots possess exceptional capabilities in maneuvering through narrow spaces, thanks to their interaction compliance and distal dexterity. However, their inherent low stiffness causes a decline in the location accuracy of the robot and could even lead to manipulation failure. To address this challenge, this paper proposes a novel type of rigid-flexible coupling robot, which increases the stiffness of the robot while ensuring the reachability within a narrow space. To achieve high-accuracy location in a narrow space, kinematic and control methods are proposed. Specifically,the robot forward kinematics are uniformly represented, and the closed-form inverse kinematics solution is derived. Furthermore, in cases where the robot?s structure fails to align with Pieper?s solution, a two-stage search strategy is utilized to solve the inverse kinematics, resulting in a high success rate of 99.1%. Based on the proposed kinematics, a rigid-dominated control method is then proposed to facilitate localization and pose alignment of target objects in narrow spaces. The practical comparative experiments show that the proposed robot has the capability of high accuracy control in narrow spaces.

关键词：

Crustal magma oxidation state and endowments in porphyry copper deposits

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Science China Earth Sciences 2025年第1期68卷 226-236页

作者： Yumin AI Massimo CHIARADIA Chao WU Huayong CHEN key laboratory of Mineralogy and Metallogeny Guangzhou Institute of Geochemistry Chinese Academy of Sciences University of Chinese Academy of Sciences Department of Earth Sciences University of Geneva Guangdong Provincial key laboratory of Mineral Physics and Materials

Porphyry copper deposits（PCDs） supply the majority of the world's copper（Cu） as well as significant amounts of molybdenum（Mo） and gold（Au）. The formation of these deposits is controlled by a variety of geological factors, among which the magmatic oxidation is one of the focuses of current research. This study investigates the redox characteristics of arc magmas by analyzing the ratio of vanadium（V） to scandium（Sc） and its correlation with the oxygen fugacity （fO2） of magmas from arcs of various crustal thicknesses globally. We compiled an extensive dataset of published V/Sc values and studied the partition coefficients of Vand Sc between minerals and silicate melts across various magmatic environments. The results demonstrate that fractional crystallization of magnetite markedly reduces V/Sc values of the residual melt. Furthermore, magnesium number（Mg#） at the onset of magnetite fractionation is strongly positively correlated with fO2of the equilibrium magma. Based on this,the oxidation of arc magmas from different crustal thicknesses can be evaluated. The result suggests that magmas generated in crusts thicker than 20 km tend to be more oxidized with increasing crust thickness. This trend is attributed to enhanced intracrustal differentiation processes involving garnet and amphibole, particularly in mature island and continental arcs. In contrast,magmas in thinner arc crusts（<20 km）, which are significantly influenced by subducted slab materials, display higher oxidation states than most of their thicker crust counterparts. These findings suggest that both subduction dynamics and crustal thickness play a vital role in determining the oxidation state of arc magmas and, consequently, their capacity to generate PCDs. Highly oxidized, primitive arc magmas are less favorable for PCD formation due to that they tend to experience magnetite fractionation and thus sulfide saturation in the early stage of magma evolution, a process leading to copper depletion. On the contra

关键词： Magma evolution V/Sc systematics Magnetite Oxygen fugacity Porphyry copper deposits

A functional cathode sodium compensation agent for stable sodium-ion batteries

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Green Energy & Environment 2025年第1期10卷 173-182页

作者： Wei Wu Zhenglin Hu Zhengfei Zhao Aoxuan Wang Jiayan Luo key laboratory for Green Chemical technology of Ministry of Education School of Chemical Engineering and TechnologyTianjin UniversityTianjin300072China State key laboratory of Metal Matrix Composites School of Materials Science and EngineeringShanghai Jiao Tong UniversityShanghai200240China Shanghai Jiao Tong University Shaoxing Research Institute of Renewable Energy and Molecular Engineering Shaoxing312000China

Hard carbon(HC)is widely used in sodium-ion batteries(SIBs),but its performance has always been limited by lowinitial Coulombic efficiency(ICE)and cycling *** compensation agent is a favorable strategy to make up for the loss of active sodium ions consumed *** it lacks agent that effectively decomposes to increase the active sodium ions as well as regulate carbon defects for decreasing the irreversible sodium ions ***,we propose 1,2-dihydroxybenzene Na salt(NaDB)as a cathode compensation agent with high specific capacity(347.9 mAh g^(-1)),lower desodiation potential(2.4–2.8 V)and high utilization(99%).Meanwhile,its byproduct could functionalize HC with more C]O groups and promote its reversible ***,the presodiation hard carbon(pHC)anode exhibits highly reversible capacity of 204.7 mAh g^(-1) with 98%retention at 5 C rate over 1000 ***,with 5 wt%NaDB initially coated on the Na3V2(PO4)3(NVP)cathode,the capacity retention of NVP t NaDBjHC cell could increase from 22%to 89%after 1000 cycles at 1 C *** work provides a new avenue to improve reversible capacity and cycling performance of SIBs through designing functional cathode compensation agent.

关键词： Hard carbon ICE Cathode compensation agent Reversible capacity Stability

Universal design of three-dimensional porous graphene-iron based promotors for kinetically rationalized lithium-sulfur chemistry

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Energy Chemistry 2025年第1期100卷 192-200页

作者： Hua Gao Yunfeng Zhang Menglei Wang Ruoxuan Yang Shuai Feng Xuan Cao Yaping Zhang Zhongyuan Lu Yingze Song State key laboratory of Environment-Friendly Energy Materials School of Materials and Chemistry Southwest University of Science and Technology School of Material Science and Engineering Henan University of Technology College of Chemistry and Chemical Engineering Taishan University

Lithium-sulfur （Li-S） batteries are widely deemed to be one of the most potential candidates for future secondary batteries because of their remarkable energy ***,notorious polysulfide shuttling and retarded sulfur reaction kinetics pose significant obstacles to the further application of Li-S *** rationally designed highly active electrocatalysts can facilitate polysulfide conversion,the universal and scalable synthesis strategies need to be ***,a universal synthetic strategy to construct a series of three-dimensional （3D） porous graphene-iron （3DGr-Fe） based electrocatalysts involving 3DGr-FeP,3DGr-Fe3C,and 3DGr-Fe3Se4is exploited for manipulating the Li-S redox *** has been observed that the implementation of a 3D porous Gr architecture leads to the well-designed conductive networks,while the uniformly dispersed iron nanoparticles introduce an abundance of active sites,fostering the lithium polysulfide conversion,thereby bolstering the overall electrochemical *** Li-S battery with the 3DGr-Fe based electrocatalyst exhibits remarkable capacity retention of 94.8%upon 100 times at 0.2 ***,the soft-packaged Li-S pouch cell based on such a 3DGr-Fe electrocatalyst delivers superior capacity of 1060.71 mA h g-1and guarantees for the continuous 30 min work of fan *** investigation gives comprehensive insights into the design,synthesis,and mechanism of 3DGr-Fe based electrocatalysts with high activity toward efficient and durable Li-S batteries.

关键词： Redox reactions