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Chinese Chemical Letters 2023年第6期34卷 583-587页

作者： Xiali Xiong Wei Geng Minna cao Rong cao State Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of MatterChinese Academy SciencesFuzhou 350002China College of Chemistry Engineering Fuzhou UniversityFuzhou 350108China University of Chinese Academy of Sciences Beijing 100049China Fujian Science&Technology Innovation Laboratory for Optoelectronic Information of China Fuzhou 350108China

Developing efficient and stable electrocatalyst to hydrogen evolution reaction adaptable for electrolytes with different p H is a big *** this work,a hierarchically structured ternary nanohybrid composed of flower-like Ru nanoparticles,rigid macrocyclic cucurbit[6]uril(CB[6])and carboxylated multiwalled carbon nanotubes(MWCNTs)was successfully prepared by chemical wet *** by the structural merits of flower-like Ru nanoparticles exposed abundant active sites supported by the MWCNTs holding superior mass transport and electrons transfer ability as well as the existence of CB[6],the obtained catalyst exhibited outstanding HER activities with overpotentials of 27,37 and 70 m V at-10 m A/cm^(2) in alkaline,acidic,and neutral electrolytes,*** the same electrocatalytic operation conditions,the HER performance is comparable or superior to commercial Pt/C catalyst(47,27and 49 m V).Besides,chronopotentiometric and accelerated stability test also revealed its extraordinary stability,which could be further employed for electrocatalytic procedure in a broad pH range.

关键词： Ruthenium Cucurbit[n]uril Hierarchical structure Hydrogen evolution reaction pH-universal

Multi-granularities capture interaction information for text matching accuracy enhancement

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The journal of China Universities of Posts and Telecommunications 2020年第1期27卷 100-108页

作者： cao Xiaopeng jin Liang School of Computer Scienceand Technology Xi’an University of Posts and TelecommunicationsXi'an 710121China

Modeling and matching texts is a critical issue in natural language processing(NLP) tasks. In order to improve the accuracy of text matching, multi-granularities capture matching features(MG-CMF) model was proposed. The proposed model used convolution operations to construct the representation of text under multiple granularities, used max-pooling operations to filter more reasonable text representations and built a matching matrix at different granularities. Then, the convolution neural network(CNN) was used to capture the matching information in each granularity. Finally, the captured matching features were input into the fully connected neural network to obtain the matching similarity. By making some experiments, the results indicate that the MG-CMF model not only gets multiple granularity representations of sentences but also can obtain matching information from multiple granularities of sentences better than the other text matching models.

关键词： representation model interaction model text matching multi-granularity capture the matching information

Recent advances in theoretical studies on ligand-controlled selectivity of nickel-and palladium-catalyzed cross-coupling reactions

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Chinese Chemical Letters 2021年第1期32卷 319-327页

作者： Mengna cao Hujun Xie Department of Applied Chemistry Zhejiang Gongshang UniversityHangzhou 310018China

Nickel-and palladium-catalyzed cross-coupling reactions have attracted wide attentions,while ligandcontrolled selectivity in these reactions are still elusive,and calculations can help obtain possible catalytic cycles to generate different products and provide insights into key factors of selectivity,which facilitates the development of new catalyst systems to control reaction *** review covers our efforts and some significant achievements from other groups on ligand-controlled reaction selectivity of coupling reactions,including introduction,computational methods,selectivity control by ligands in Niand Pd-catalyzed coupling reactions,as well as summary and future perspectives.

关键词： DFT calculations Pd catalysis Ni catalysis Selectivity Reaction mechanism Ligand

Upcrossing-based time-dependent resilience of aging structures

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Resilient Cities and Structures 2024年第3期3卷 20-27页

作者： cao Wang School of Civil and Environmental Engineering University of Technology SydneyUltimoNSW 2007Australia

The time-dependent resilience of an in-service aging structure provides quantitative measure of the structural ability to prepare for,adapt to,withstand and recover from disruptive *** models have been proposed in the literature to evaluate the resilience of aging structures subjected to discrete load processes,which are,however,not applicable to handle resilience problems considering continuous load *** this paper,a new method is developed to evaluate the time-dependent resilience of aging structures subjected to a continuous load *** proposed method serves as the complement of the existing resilience models addressing discrete load processes,and takes into account the aging effects of the structural resistance/capacity and the nonstationarity in loads as a result of climate change.A structure suffers from a damage state upon the occurrence of an upcrossing of the load effect with respect to the resistance/capacity,leading to the reduction of the performance function,followed by a recovery process that restores the *** proposed method enables the time-dependent resilience to be evaluated via a closed form *** is also revealed that,the proposed resilience model takes an extended form of the existing formula for upcrossing-based time-dependent reliability,thus establishing a unified framework for the two *** applicability of the proposed method is demonstrated through examining the time-dependent resilience of a residential building subjected to wind *** effects of key factors on resilience,including the nonstationarity and correlation structure of the load process,as well as the resistance/capacity deterioration scenario,are investigated through an *** particular,the structural resilience would be overestimated if ignoring the potential impacts of climate change,which is a relatively non-conservative evaluation.

关键词： Time-dependent resilience Stochastic load process Multiple damage states Upcrossing Closed form solution

Single-cell sequencing delivers hematopoietic stem cell specification

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Science Bulletin 2016年第18期61卷 1419-1421页

作者： jiani cao Tongbiao Zhao State Key Laboratory of Stem Cell and Reproductive Biology Institute of Zoology Chinese Academy of Sciences

Recently,Zhou et al.[1]have successfully traced the hematopoietic stem cell(HSC)specification during the stepwise development of HSC from the pre-HSC stage at single-cell *** findings offer fundamental insights into mouse HSC fate decision and provide extensive information that may lead to novel discoveries in HSC ***,standing at the apex of the hierarchy

关键词：造血干细胞单细胞测序 HSC 细胞分化分辨率扩展性小鼠

Broadband hybrid model for relay-aided cooperative MIMO power line communication systems

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The journal of China Universities of Posts and Telecommunications 2020年第1期27卷 72-80页

作者： Liang Xiaolin cao Wangbin School of Electronic and Information Engineering Hebei UniversityBaoding 071002China School of Electrical and Electronic Engineering North China Electric Power UniversityBaoding 071000China

A hybrid model for broadband multiple-input multiple-output(MIMO) relay-aided indoor power line communications(PLC) system was proposed in this paper. The proposed model combines the top-down and bottom-up approaches and extends to a two-hop relay-aided cooperative system with variable gain relay in amplify-and-forward(AF) mode. Based on the proposed PLC model and generated channel, the channel statistical characteristics are further investigated in 2 MHz^100 MHz bandwidth. Simulated results show that the proposed model overcomes the difficulties that the existing models need a lot of topological information of the network or measurements information. It provides a practical simulation analysis method for cooperative relay MIMO-PLC system. The results also show that cooperative MIMO relaying communications can improve the indoor PLC performances and communication reliability.

关键词： broadband communication channel frequency response(CFR) hybrid model MIMO-PLC power line communications(PLC) relay-aided

Numerical simulation of gas migration into mining-induced fracture network in the goaf

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International journal of Mining Science and Technology 2017年第4期27卷 681-685页

作者： cao jie Li Wenpu State Key Laboratory of Gas Disaster Detection Prevention and Emergency Control. Chongqing 400037. China Chongqing Research Institute Co. Ltd. of China Coal Technology and Engineering Group Chongqing 400037 China State Key Laboratory of Coal Mine Disaster Dynamics and Control. Chongqing University. Chongqing 400044 China

Gas extraction practice has been proven for the clear majority of coal mines in China to be unfavorable using drill holes in the coal seam. Rather, mining-induced fractures in the goaf should be utilized for gas extraction. To study gas migration in mining-induced fractures, one mining face of 10 th Mine in Pingdingshan Coalmine Group in Henan, China, has been selected as the case study for this work. By establishing the mathematical model of gas migration under the influence of coal seam mining, discrete element software UDEC and Multiphysics software COMSOL are employed to model gas migration in mining-induced fractures above the goaf. The results show that as the working face advances, the goaf overburden gradually forms a mining-induced fracture network in the shape of a trapezoid, the size of which increases with the distance of coal face advance. Compared with gas migration in the overburden matrix, the gas flow in the fracture network due to mining is far greater. The largest mining-induced fracture is located at the upper end of the trapezoidal zone, which results in the largest gas flux in the network. When drilling for gas extraction in a mining-induced fracture field, the gas concentration is reduced in the whole region during the process of gas drainage, and the rate of gas concentration drops faster in the fractured zone. It is shown that with gas drainage, the gas flow velocity in the mininginduced fracture network is faster.

关键词： Gas migration Fractures Mining-induced Numerical simulation

A generalized index for functionality-sensitive resilience quantiﬁcation

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Resilient Cities and Structures 2023年第1期2卷 68-75页

作者： cao Wang School of Civil MiningEnvironmental and Architectural EngineeringUniversity of WollongongWollongongNSW 2522Australia

The resilience index based on the integral of functionality/performance function within a time interval of interest has been widely used in the ***,it cannot fully reﬂect the sensitivity of the resilience of the object(e.g.,structure or system)to the variation of *** this paper,a generalized index is proposed to measure the resilience of structures and systems that is sensitive to the instantaneous functionality,as reﬂected by a generating function involved in the proposed resilience *** mathematical properties of the proposed resilience model are *** is proven that,the proposed index varies within[0,1],and is a monotone *** the generating function is a power function with α being the exponent(called α-fairness function),the additivity property(i.e.,superadditivity,additivity,and subadditivity)of the resilience index is dependent on the value of α.It is also observed that the existing resilience index is a special case of the proposed one.A byproduct is that,with a properly selected generating function,the time-dependent reliability problem of an aging structure can also be described by the proposed resilience *** applicability of the proposed resilience model is demonstrated through four examples.

关键词： Resilience index Functionality-sensitive Monotone measure

Dynamically reconfigurable topological edge state in phase change photonic crystals

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Science Bulletin 2019年第12期64卷 814-822页

作者： Tun cao Linhan Fang Ying cao Nan Li Zhiyou Fan Zhiguo Tao School of Optoelectronic Engineering and Instrumentation Science Dalian University of TechnologyDalian 116024China China North Vehicle Research Institute Beijing 100072China

The observation of topological edge states(TESs) revolutionized our understanding of scattering and propagation of electromagnetic(EM) waves. Supported by topological robustness, the TES at the interface between trivial and non-trivial insulators was not reflected from the structural disorders and imperfections. Recently topological photonic crystals(PhCs) were demonstrated to obtain remarkable one-way propagation of the TES, having the advantages of lossless propagation, dense integration, and high fabrication tolerance over conventional PhCs. Nevertheless, the lack of reversible switching of TES possesses significant limitations in helicity/spin filtering and tunable photonic devices. We proposed a topological PhC based on a prototypical phase-change material, Ge2 Sb2 Te5(GST225) to solve the problem. We find that at a particular frequency, the TES within the structure can be reversibly switched between "on"and "off" by transiting the GST225 structural state between amorphous and crystalline. Moreover, the topology of the PhC was maintained since the tuning of TES was achieved by varying the refractive index of GST225 instead of the structural geometry. This provides a continuous change of the spectral position of the photonic bandgap and TES by gradually crystallising the GST225. We show that the phase change of GST225 from amorphous to crystalline and vice versa can be engineered in nanoseconds. Our proof of concept may offer a platform for dynamically tuning the TESs that might otherwise be challenging to attain in photonic systems. We expect it to have potential applications for photonic devices in topological optical circuits and scatter-free one-way light propagation.

关键词： Phase change materials Photonic crystals Topological edge states Tunability Reconfigurability

EVOLUTION OF THE ELECTROCHEMICAL CHARACTERISTICS DURING PITTING CORROSION OF PURE ALUMINUM IN SODIUM CHLORIDE SOLUTION

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Acta Metallurgica Sinica(English Letters) 2005年第4期18卷 525-532页

作者： Z. Zhang C. Cai F.H. cao Z.N. Gao j.Q. Zhang C.N. cao Department of Chemistry Zhejiang University Hangzhou 310027 China Department of Chemistry Ningxia University Yinchuan 750021 China State Key Laboratory for Corrosion and Protection of Metals Institute of Metal Research The Chinese

The corrosion behavior of pure aluminum in neutral 3.0% （mass fraction） sodium chloride （Na-Cl） solution has been studied using electrochemical impedance spectroscopy （EIS） measurement in conjunction with the scanning electron microscopy （SEM） technique. EIS information on the evolution of pitting corrosion over a period of 15 days has been obtained and analyzed with equivalent circuit technique. The results shown that, during the ensemble constant immersion time, two time constants involved, the high frequency one originated from the protective layer on the corroding surface while the low frequenO, one from the diffusion process or the corrosion reaction and so on. And there existed a period for oxide film to growth and thickening prior to the of the attacking of chloride ions to the substrate. Meanwhile, good relationship between EIS and the material corrosion type/severity has been obtained, which has been interpreted according to the characteristics of corrosion process such as auto acceleration of pitting corrosion and the protection of local anodic reaction to the area around them.

关键词： pure aluminum pitting corrosion electrochemical impedance spectroscopy pit-rnorphology