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Recent development of Au arched Pt nanomaterials as promising electrocatalysts for methanol oxidation reaction

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Nano Research 2022年第1期15卷 18-37页

作者： Wenhua lou Asad Ali Pei kang Shen Collaborative Innovation Center of Sustainable Energy Materials Guangxi Key Laboratory of Electrochemical Energy MaterialsGuangxi UniversityNanning 530004China School of Physical Science and Technology Guangxi UniversityNanning 530004China School of Chemistry&Chemical Engineering Guangxi UniversityNanning 530004China

The recent development of Aurum(Au)introduced Platinum(Pt)based nanomaterials is of great significance to direct methanol fuel cell as electrocatalysts for anode reactions,due to its stability and anti-poisoning ***,the performance of PtAu based catalysts with different elements,atomic ratio,and morphology was studied in methanol solution to further improve its electrocatalytic ***,the effects of Au have aroused the researchers'attention in Pt-based *** this review,we summarize the controllable synthesis,mechanism,and catalytic performance of Au introduced Pt-based electrocatalysts such as PtAu core-shell nanostructures,PtAu dendrite,PtAu nanowires,self-supporting Au@Pt NPs,and Au@Pt star-like nanocrystals for the methanol oxidation ***,the challenges and research directions for the future development of PtAu based catalysts are provided.

关键词： methanol oxidation reaction(MOR) direct methanol fuel cell(DMFC) PtAu based catalysts anode catalysts electrocatalysis

Gas Flow Development Through Tandem Heat Exchangers Inside Exhaust Nozzle by Using Porous Medium Model

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Transactions of Nanjing University of Aeronautics and Astronautics 2016年第2期33卷 147-154页

作者： Liu Xiyue Zhang Jingzhou lou Decang kang Yong College of Energy and Power Engineering Jiangsu Province Key Laboratory of Aerospace Power System Nanjing University of Aeronautics and Astronautics Nanjing 210016 P. R. China Collaborative Innovation Center of Advanced Aero-Engine Beijing 100191 P. R. China China Gas Turbine Establishment Chengdu 610500 P. R. China

A computational study on the flow development through tandem double-U-shaped-tubes compact heat exchangers inside exhaust nozzle is *** order to simplify the computational process on modeling the flow field,the compact heat exchanger is modeled as a porous matrix by using an isotropic porous medium assumption,which makes two-dimensional numerical simulation *** the use of an existed quadratic relation which connects the pressure drop with the inlet velocity in the external part of the heat exchanger,the permeability and drag coefficient in the porous medium model are determined and a corresponding computational method validation is also *** schemes of tandem double-U-shaped-tubes compact heat exchangers are numerically *** relative to the baseline scheme,the modified scheme is improved by smoothing the nozzle expansion,varying heat exchanger mounting angle and installing boat-tail ramp at the trailing edge of the last heat *** results show that the pressure losses due to the existence of local recirculation zones and inappropriate distribution of the flow field are reduced in the modified *** pressure loss coefficient is decreased from 1.7% under the baseline scheme to 1.2% under the modified scheme.

关键词： compact heat exchanger exhaust nozzle porous medium pressure loss numerical simulation

First report of the genus Orencostoma Moriuti(Lepidoptera: Yponomeutidae) from China, with descriptions of two new species

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Zoological Systematics 2019年第1期44卷 76-83页

作者： kang lou Juan Li Shuxia Wang College of Life Sciences Nankai University

The genus Orencostoma Moriuti, 1971 is recorded for the first time in China. Two new species, O. divulgatum Wang sp. nov. and O. semicirculum Wang sp. nov., are described. Photographs of adults, venations and male gen... 详细信息

关键词： Yponomeutioidea taxonomy new record

Controlled Radical Polymerization of Styrene in the Presence of Different Copper Complexes and Organic Halides

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Chemical Research in Chinese Universities 1999年第4期15卷 358-363页

作者： CHENG Guang-lou HU Chun-pu YING Sheng-kang Laboratory of Living Polymerization East China University of Science and TechnologyShanghai 200237P.R.China

The polymerization behaviors of Styrene (St) in the presence of CuX/L [X=Cl or Br; L= 2,2 bipyridine (bpy), 1,10 phenanthroline (phen) or 4,7 diphenyl 1,10 phenanthroline (DPP) ] and R X (R=trichloromethyl, benzyl or allyl; X=Cl or Br) have been studied and examined. In a CuCl/bpy/RCl/St system, a bimodal GPC peak at the early stage of polymerization was observed, and a concept of multi active species was proposed to explain this phenomenon. In a CuCl/phen (DPP)/RCl/St system, the \%M\%\-n of polystyrene (PS) increased linearly with St conversion and ln[M] o/[M] also increased linearly with time, indicating the living nature of this system. Furthermore, the stability of the propagating active species in a CuBr/phen/RBr/St system is higher than that in the CuBr/phen/RBr/St system.

关键词： ATRP 'Living'/controlled radical polymerization 1,10-Phenanthroline 4,7-Diphenyl-1,10-phenanthroline Cuprous halides Styrene

Mechanical behavior and failure mechanisms of rock bolts subjected to static-dynamic loads

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International Journal of Mining Science and Technology 2024年第3期34卷 281-288页

作者： Hongpu kang Guiyang Yuan Linpo Si Fuqiang Gao Jinfu lou Jinghe Yang Shuangyong Dong CCTEG Coal Mining Research InstituteBeijing 100013China State Key Laboratory of Intelligent Coal Mining and Strata Control Beijing 100013China

This study explores the effects of dynamic and static loading on rock bolt performance a key factor in maintaining the structural safety of coal mine roadways susceptible to coal *** a housemade load frame to simulate various failure scenarios,pretension-impact-pull tests on rock bolts were conducted to scrutinize their dynamic responses under varied static load conditions and their failure traits under combined *** experimental results denote that with increased impact energy,maximum and average impact loads on rock bolts escalate significantly under pretension,initiating plastic deformation beyond a certain *** minor reductions in the yield load due to impactinduced damage,pretension aids in constraining post-impact deformation rate and fluctuation degree of rock ***,impact-induced plastic deformation causes internal microstructure dislocation,fortifying the stiffness of the rock bolt support *** magnitude of this fortification is directly related to the plastic deformation induced by the *** findings provide crucial guidance for designing rock bolt support in coal mine roadway excavation,emphasizing the necessity to consider both static and dynamic loads for improved safety and efficiency.

关键词： Rock bolt Pretension Static and dynamic load Impact

Enhanced potassium storage of carbon nanofibers as binderfree anodes enabled by coupling ultra-small amorphous Sb_(2)O_(3),graphene modification and sulfur doping

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Rare Metals 2024年第1期43卷 51-64页

作者： Zhao Huang Yu-kang lou Lin Peng Yuan Peng Meng-Meng Wang Ming Zhang College of Railway Transportation Hunan University of TechnologyZhuzhou 412007China College of Semiconductors(College of Integrated Circuits) Changsha Semiconductor Technology and Application Innovation Research InstituteHunan UniversityChangsha 410082China Key Laboratory for Micro-Nano Optoelectronic Devices of Ministry of Education College of Semiconductors(College of Integrated Circuits)Hunan UniversityChangsha 410082China

Considering the intrinsic advantages of natural copiousness and cost-effectiveness of potassium resource,potassium-ion batteries(KIBs) are booming as prospective alternatives to lithium-ion batteries(LIBs) in large-scale energy storage scenarios. Nevertheless, lacking desirable electrodes for reversibly hosting the bulky K+hinders the widespread application of KIBs, and it needs to be urgently solved. Hereon, the porous S-doped Sb_(2)O_(3)-graphene-carbon(SAGC) nanofibers are manufactured through an adjustable and facile approach, which involves electrospinning, in situ etching and sulfuration. The synthesized SAGC is featured by the ultra-small amorphous Sb_(2)O_(3) homogeneously wrapped inside the carbon matrix, as well as the co-incorporation of graphene and sulfur. Tentatively,the SAGC nanofiber sheets are applied as binder-free anodes for KIBs, exhibiting a prominent cycling life(256.72 m Ah·g^(-1) over 150 cycles at 100 m A·g^(-1)) and rate·g^(-1) over 100 cycles at 1 A·g^(-1)). The positive synergy among all the active components accounts for the distinguished performances of the SAGC. By reinforcing the tolerability to the swelling stress, producing the valid electrochemical active sites, and promoting the charge transferring for reversible K+uptake, the SAGC finally renders the excellent cyclability, capacity, and rate capability. Moreover, the extrinsic electrochemical pseudocapacitance characteristics induced by the porous carbon substrate elevate the K-storage capacity of the SAGC as well. It is hoped that the conclusions drawn may offer new insights into a direction for the high-performance binderfree KIB anodes.

关键词： S-doped Sb_(2)O_(3)-graphene-carbon Nanofibers Binder-free Anodes Potassium-ion batteries

Pea leafminer Liriomyza huidobrensis (Diptera: Agromyzidae) uses vibrational duets for efficient sexual communication

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Insect Science 2019年第3期26卷 510-522页

作者： Jin Ge Jia-Ning Wei Ding-Jie Zhang Chun hi De-Zhi Zheng Le kang State Key Laboratory of Integrated Management of Pest Insects and Rodents Institute of Zoology Chinese Academy of Sciences Beijing China University of Chinese Academy of Sciences Beijing China Key Laboratory of Zoological Systematics and Evolution Institute of Zoology Chinese Academy of Sciences Beijing China School of Instrumentation Science & Optoelectronics Engineering Beihang University Beijing China Beijing Institutes of Life Science Chinese Academy of Sciences Beijing China

The pea leafminer (Liriomyza huidobrensis) is a notorious pest of vegetables and ornamental plants worldwide. Despite a large number of studies on its biology and ecology, the courtship behavior and sexual communication of this species remain unclear. Here, we studied vibrational communication in the sexual interaction of the pea leafminer. On host plant leaves, females and males behaviorally displayed the bobbing-quivering alternation, which finally led to copulation. Moreover, records of laser vibrometry revealed threesignal duets underlying the behavioral alternation. Sexually mature males spontaneously emitted calls (MCs) to initiate the duets. The females rapidly responded to MCs by emitting replies (FRs) that are longer in duration. The FRs further triggered male replies (MRs) in their search for potential partners. Leafminer-produced vibrational signals convey efficient information to partners and generate pair formation on stretched substrates, such as plant leaves and nylon mesh, but cannot elicit responses on dense substrates, such as glass and plastic. Vibrational playbacks of both MCs and FRs can elicit replies in females and males, respectively. This study completely characterizes substrate-borne vibrational duets in a dipteran insect. The discovery of vibrational sex signals in the pea leafminer provides new insights for the development of novel approaches to control the pest and its relative species.

关键词： biotremology courtship behavior Liriomyza vibrational communication

Study on the pointing model of a slant-axis terahertz antenna

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Research in Astronomy and Astrophysics 2020年第4期20卷 115-122页

作者： Yu Wang Zheng lou Ying-Xi Zuo Hao-Ran kang Ming-Zhu Zhang Purple Mountain Observatory Chinese Academy of SciencesNanjing 210034China Key Laboratory for Radio Astronomy Chinese Academy of SciencesNanjing 210034China Shanghai Normal University Shanghai 201400China University of Science and Technology of China Hefei 230026China

This paper describes the establishment and verification of an accurate pointing model for a1.2 m aperture slant-axis terahertz antenna.A new analytical pointing model for the slant-axis antenna is presented based on an analogy to that of the alt-azimuth ***,extra error terms are added to the pointing model based on the structure and mechanical analysis of the slant-axis *** verify the pointing model experimentally,a pointing error measurement method based on photogrammetric techniques is *** this method,pointing behaviors of the antenna are accurately measured without the aid of astronomical observations,and major sources of the pointing errors are measured individually by photogrammetry and their respective coefficients are compared with those in the analytical pointing *** results show that an extended pointing model consisting 21 error terms can significantly reduce the residual systematic errors compared with the traditional model,more details are given in the following sections.

关键词： telescopes slant-axis antenna photogrammetry pointing models

Numerical experimental study on the potential climatic impacts oflarge-scale wind farms in China

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Advances in Climate Change Research 2019年第3期10卷 143-149页

作者： HUANG Jian-Bin lou Peng-kang SUN Hong-Wei LUO Yong ZHAO Zong-Ci Ministry o f Education Key Laboratory for Earth System Modeling Department o f Earth System ScienceTsinghua University100084BeijingChina

Wind energy has been rapidly developed in China during the past decades and the installed capacity has been the largest in the world. In the future, utilization of wind power is still expected to carry out in China mainly with a large-scale centralized layout. Here, we examine the potential climatic impacts of large-scale windfarms associated with deployment scale in China using numerical experiments, in which four deployment scenarios were designed. These four scenarios represented relatively small- (484 GW), medium- (2165 GW) and large-scale (3490 GW and 5412 GW) installed wind power capacities, respectively. Results showed that turbulent kinetic energy, wind velocity, and air temperature varied consistently within those windfarms with the largest changes in turbine hub heights. Moreover, the above relatively large- scale windfarms could induce regional wanning with a maximum of above 0.8 °C in North China. This regional warming may be linked to an anomalous circulation pattern with a negative pressure anomaly center in Northeast China and a positive pressure anomaly center in the middle and lower reaches of the Yangtze-Huaihe River Basin.

关键词： Climatic impact Large-scale windfarms Wind energy China WRF model