检索结果-南通市图书馆

Journal of Rare Earths 2024年第3期42卷 570-577,I0005页

作者： Yudi guo Erqing Zhao Xiaofang Zhao Shuailei liu School of Chemistry and Materials Engineering Xinxiang UniversityXinxiang453003China School of Chemistry and Chemical Engineering Henan Institute of Science and TechnologyXinxiang453003China

The research of poly(ethylene oxide)(PEO)-based solid composite electrolyte with high ionic conductivity and excellent interfacial stability is the key to the development of all-solid-state lithium-ion batteries(ASSLIBs). Herein, uniform nanorod structured CeO_(2) fillers were controllably synthesized by electrospinning, which were subsequently filled into PEO polymer to prepare CeO_(2)/PEO solid composite electrolyte. The addition of CeO_(2) nanorods can reduce both the glass transition temperature and the melting point of PEO polymer, and also interact with PEO and lithium bis(trifluoromethanesulphonyl)imide(LITFSI) by Lewis acid—base reaction. Therefore, the solid composite electrolyte exhibits a high ionic conductivity of 4.52 × 10^(-4)S/cm, a wide electrochemical stability window of about 4.8 V, and a good interfacial stability with Li at 55℃. Moreover, the LiFePO_4/Li ASSLIB divulges the discharging specific capacity of 165, 162, 156 and 146 mA,h/g at 0.2, 0.5, 1 and 2 C, respectively, and achieves the capacity retention of 90.3% after 150 cycles at 0.5 C. Consequently, one dimensional CeO_(2) nanorods can be considered as an alternative filler for polymeric solid electrolyte.

关键词： Poly(ethylene oxide) Solid composite electrolyte CeO_(2)nanorods Ionic conductivity Rare earths

NAD(P)H inspired CO_(2) reduction and beyond

在线全文

学校读者我要写书评

暂无评论

Science China Chemistry 2024年第4期67卷 1044-1046页

作者： Wenjin Dong jian liu Qingdao Institute of Bioenergy and Bioprocess Technology Chinese Academy of SciencesShandong Energy InstituteQingdao 266101China

The catalytic reduction of carbon dioxide to fuels and valueadded chemicals under mild conditions is recognized as a promising strategy to alleviate the energy *** the Calvin cycle of natural photosynthesis,CO_(2)reduction is achieved using cofactor nicotinamide adenine dinucleotide phosphate(NADPH)as a practical catalyst,shedding light on the biomimetic metal-free reduction of CO_(2).

关键词： dioxide dinucleotide catalyst

Unbound^(28)O,the heaviest oxygen isotope observed:a cutting-edge probe for testing nuclear models

在线全文

学校读者我要写书评

暂无评论

Nuclear Science and Techniques 2024年第2期35卷 1-2页

作者： jian-guo Li Bai-Shan Hu Shuang Zhang Fu-Rong Xu School of Physics and State Key Laboratory of Nuclear Physics and TechnologyPeking UniversityBeijing 100871China Institute of Modern Physics Chinese Academy of SciencesLanzhou 730000China Southern Center for Nuclear-Science Theory(SCNT) Institute of Modern PhysicsChinese Academy of SciencesHuizhou 516000China

The beyond-dripline oxygen isotopes^(27,28)O were recently observed at RIKEN,and were found to be unbound decaying into^(24)O by emitting *** unbound feature of the heaviest oxygen isotope,^(28)O,provides an excellent test for stateof-the-art nuclear *** atomic nucleus is a self-organized quantum manybody system comprising specific numbers of protons Z and neutrons N.

关键词： testing quantum system

Exact Box-Constrained Economic Operating Region for Power Grids Considering Renewable Energy Sources

在线全文

学校读者我要写书评

暂无评论

Journal of Modern Power Systems and Clean Energy 2024年第2期12卷 514-523页

作者： Huating Xu Bin Feng Chutong Wang Chuangxin guo jian Qiu Mingyang Sun College of Electrical Engineering Zhejiang UniversityHangzhou 310027China Department of Control Science and Engineering Zhejiang UniversityHangzhou 310027China

The growing integration of renewable energy sources manifests as an effective strategy for reducing carbon emissions. This paper strives to efficiently approximate the set of optimal scheduling plans(OSPs) to enhance the performance of the steady-state adaptive cruise method(SACM) of power grid, improving the ability of dealing with operational uncertainties. Initially, we provide a mathematical definition of the exact boxconstrained economic operating region(EBC-EOR) for the power grid and its dispatchable components. Following this, we introduce an EBC-EOR formulation algorithm and the corresponding bi-level optimization models designed to explore the economic operating boundaries. In addition, we propose an enhanced big-M method to expedite the computation of the EBCEOR. Finally, the effectiveness of the EBC-EOR formulation, its economic attributes, correlation with the scheduling plan underpinned by model predictive control, and the significant improvement in computational efficiency(over twelvefold) are verified through case studies conducted on two test systems..

关键词： Exact box-constrained economic operating region(EBC-EOR) big-M method intelligent scheduling steady-state adaptive cruise uncertainty renewable energy source

The reaction mechanism and interfacial crystallization of Al nanoparticle-embedded Ni under shock loading

在线全文

学校读者我要写书评

暂无评论

Defence Technology（防务技术） 2024年第3期33卷 114-124页

作者： Yifan Xie jian-Li Shao Rui liu Pengwan Chen State Key Laboratory of Explosion Science and Technology Beijing Institute of TechnologyBeijing100081China Explosion Protection and Emergency Disposal Technology Engineering Research Center of the Ministry of Education Beijing100039China

The shock-induced reaction mechanism and characteristics of Ni/Al system,considering an Al nanoparticle-embedded Ni single crystal,are investigated through molecular dynamics *** the shock melting of Al nanoparticle,interfacial crystallization and dissolution are the main *** reaction degree of Al particle first increases linearly and then logarithmically with time driven by rapid mechanical mixing and following *** reaction rate increases with the decrease of particle diameter,however,the reaction is seriously hindered by interfacial crystallization when the diameter is lower than 9 nm in our ***,we found a negative exponential growth in the fraction of crystallized Al atoms,and the crystallinity of B2-NiAl(up to 20%)is positively correlated with the specific surface area of Al *** can be attributed to the formation mechanism of B2-NiAl by structural evolution of finite mixing layer near the collapsed *** shock melting of both Al particle and Ni matrix,the liquid-liquid phase inter-diffusion is the main reaction mechanism that can be enhanced by the formation of internal *** addition,the enhanced diffusion is manifested in the logarithmic growth law of mean square displacement,which results in an almost constant reaction rate similar to the mechanical mixing process.

关键词： Shock-induced reaction Molecular dynamics simulations Interfacial crystallization Reaction mechanism

Alignment efficient image-sentence retrieval considering transferable cross-modal representation learning

在线全文

学校读者我要写书评

暂无评论

Frontiers of Computer Science 2024年第1期18卷 77-91页

作者： Yang YANG Jinyi guo Guangyu LI Lanyu LI Wenjie LI jian YANG School of Computer Science and Engineering Nanjing University of Science and TechnologyNanjing 210094China Department of Computing Hong Kong Polytechnic UniversityHong Kong 100872China State Key Lab.for Novel Software Technology Nanjing UniversityNanjing 210094China 14th Research Institute of China Electronics Technology Group Corporation Nanjing 210094China guangyu.li2017@***

Traditional image-sentence cross-modal retrieval methods usually aim to learn consistent representations of heterogeneous modalities,thereby to search similar instances in one modality according to the query from another modality in *** basic assumption behind these methods is that parallel multi-modal data(i.e.,different modalities of the same example are aligned)can be obtained in *** other words,the image-sentence cross-modal retrieval task is a supervised task with the alignments as ***,in many real-world applications,it is difficult to realign a large amount of parallel data for new scenarios due to the substantial labor costs,leading the non-parallel multi-modal data and existing methods cannot be used *** the other hand,there actually exists auxiliary parallel multi-modal data with similar semantics,which can assist the non-parallel data to learn the consistent ***,in this paper,we aim at“Alignment Efficient Image-Sentence Retrieval”(AEIR),which recurs to the auxiliary parallel image-sentence data as the source domain data,and takes the non-parallel data as the target domain *** single-modal transfer learning,AEIR learns consistent image-sentence cross-modal representations of target domain by transferring the alignments of existing parallel ***,AEIR learns the image-sentence consistent representations in source domain with parallel data,while transferring the alignment knowledge across domains by jointly optimizing a novel designed cross-domain cross-modal metric learning based constraint with intra-modal domain adversarial ***,we can effectively learn the consistent representations for target domain considering both the structure and semantic ***,extensive experiments on different transfer scenarios validate that AEIR can achieve better retrieval results comparing with the baselines.

关键词： image-sentence retrieval transfer learning semantic transfer structure transfer

Global stability coefficient of large underground caverns under static loading and earthquake wave condition

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 Central South University 2024年第8期31卷 2826-2843页

作者： Chen, Peng-fei jiang, Quan liu, jian Li, Shao-jun Chen, Tao He, Ben-guo State Key Laboratory of Geomechanics and Geotechnical Engineering Institute of Rock and Soil Mechanics Chinese Academy of Sciences Wuhan China University of Chinese Academy of Sciences Beijing China Power China Chengdu Engineering Corporation Limited Chengdu China Key Laboratory of Ministry of Education on Safe Mining of Deep Metal Mines Northeastern University Shenyang China

Underground energy and resource development, deep underground energy storage and other projects involve the global stability of multiple interconnected cavern groups under internal and external dynamic disturbances. An evaluation method of the global stability coefficient of underground caverns based on static overload and dynamic overload was proposed. Firstly, the global failure criterion for caverns was defined based on its band connection of plastic-strain between multi-caverns. Then, overloading calculation of the boundary geostress and seismic intensity on the caverns model was carried out, and the critical unstable state of multi-caverns can be identified, if the plastic-strain band appeared between caverns during these overloading processes. Thus, the global stability coefficient for the multi-caverns under static loading and earthquake was obtained based on the corresponding overloading coefficient. Practical analysis for the Yingliangbao (YLB) hydraulic caverns indicated that this method can not only effectively obtain the global stability coefficient of caverns under static and dynamic earthquake conditions, but also identify the caverns’ high-risk zone of local instability through localized plastic strain of surrounding rock. This study can provide some reference for the layout design and seismic optimization of underground cavern group.

关键词： underground caverns global stability coefficient static-dynamic overload local instability

Enhanced Grain Refining Effect of Mg–Zr Master Alloy on Magnesium Alloys via a Synergistic Strategy Involving Heterogeneous Nucleation and Solute‑Driven Growth Restriction

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Acta Metallurgica Sinica(English Letters) 2024年第8期37卷 1354-1366页

作者： Gang Zeng Hong liu Jing‑Peng Xiong jian‑Long Li Yong liu Key Laboratory of Lightweight and High Strength Structural Materials of jiangxi Province School of Advanced ManufacturingNanchang UniversityNanchang 330031China

Zirconium(Zr)emerges as the most effective grain refiner for magnesium(Mg)alloys incorporating ***,Zr is introduced in the form of an Mg–Zr master ***,within Mg–Zr master alloys,Zr predominantly exists in a particle form,which tends to aggregate due to attractive van der Waals *** clustered Zr is prone to settling,thereby reducing its refining impact on Mg *** this work,a combined pretreatment process for Mg–Zr master alloys was proposed,encompassing the introduction of a physical field to intervene the agglomeration of particle Zr and the employ of high-temperature dissolution and peritectic reactions to promote the solid solution of *** results demonstrate that the particle Zr within the pretreated Mg–Zr master alloy is effectively dispersed and refined,and greater solute Zr levels can be *** subsequent grain refinement ability was studied on a typical Mg–6Zn–0.6Zr(wt%)*** outcome highlights that an improvement in the grain refinement efficacy(32.4%)of Mg–Zr master alloys was obtained with a holding time of 60 *** pretreated Mg–Zr master alloy significantly augments the efficiency of grain refinement for Mg alloys through a synergistic strategy involving heterogeneous nucleation and solute-driven growth *** crucial factor in achieving effective grain refinement of Zr in Mg alloys lies in regulating the presence and morphology of Zr in the Mg–Zr master alloy,distinguishing between particle Zr and solute *** study introduces a novel method for developing more efficient Mg–Zr refiners.

关键词： Magnesium alloy Mg-Zr master alloy Grain refinement Heterogeneous nucleation Solute-driven growth restriction Synergistic strategy

Co/Fe Dual Catalysis for Sequential Hydrosilylation-Isomerization:Access to Trisubstituted(E)-Alkenyl Silanes from Terminal Alkynes

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Journal of Chemistry 2024年第16期42卷 1860-1866页

作者： Zhihao guo Guixia liu Zheng Huang Chang-Kung Chuang Institute East China Normal UniversityShanghai 200062China The State Key Laboratory of Organometallic Chemistry Shanghai Institute of Organic ChemistryUniversity of Chinese Academy of SciencesChineseAcademyof SciencesShanghai200032China School of Chemistry and Materials Science Hangzhou Institute of Advanced StudyUniversity of Chinese Academy of SciencesHangzhouZhejiang310024China

By rational modification of electronic and steric properties of pincer ligands,a Co/Fe dual catalyst system is developed for one-pot sequential Markovnikov alkyne hydrosilylation and stereoselective alkene *** protocol provides an atom-economical and efficient approach to trisubstituted(E)-alkenyl silanes from widely accessible terminal alkynes with high regio-and stereoselectivities under mild *** utility of this reaction was demonstrated by gram-scale synthesis and derivatization of bioactive *** radical clock and trapping experiments indicated that radical pathway might be operative in the alkene isomerization step.

关键词： Cobalt Dual catalysis Hydrosilylation Iron Isomerization Trisubstituted alkenyl silanes

Some Simple Groups Which are Determined by Their Orders and Degree-Patterns

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Algebra Colloquium 2024年第2期31卷 341-346页

作者： Qinghong guo Weijun liu Genghua Fan School of Mathematics and Statistics HNP-LAMACentral South University Changsha 410083China College of General Education Guangdong University of Science and Technology DongguanGuangdong 523083China 不详

Let G be a finite group and Irr(G)the set of all irreducible complex characters of *** cd(G)be the set of all irreducible complex character degrees of G and denote byρ(G)the set of all primes which divide some character degree of *** character-prime graphΓ(G)associated to G is a simple undirected graph whose vertex set isρ(G)and there is an edge between two distinct primes p and q if and only if the product p q divides some character degree of *** show that the finite nonabelian simple groups A_(7),J_(1),J_(3),J_(4),L_(3)(3)and U_(3)(4)are uniquely determined by their degree-patterns and orders.

关键词： irreducible complex character character-prime graph finite nonabelian simple group