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numerical simulation and experimental detection of leaky lamb waves induced by pulse laser at air-solid interfaces

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Science China(Physics,Mechanics & Astronomy) 2008年第6期51卷 607-616页

作者： ZHAo Yan SHEn ZhongHua lU Jian ni XiaoWu School of Science Nanjing University of Science&TechnologyNanjing 210094China

Based on the thermoelastic mechanism of laser ultrasonic, the problems of the thermal conduction and the coupling between the motion of solid and fluid are solved by using the finite element method. And then the transient waveforms of leaky lamb waves induced by pulse laser action on the air-aluminum interface are obtained. Experimental signals of laser-induced leaky lamb waves at the air-alu- minum interface are detected by applying an our-developed detector, based on the light deflection principle. The dispersion and attenuation properties of leaky lamb waves are analyzed through the phase spectral analysis.

关键词： laser ultrasonic leaky lamb wave air-solid interface finite element method light deflection

EFFECT oF InTRAMolECUlAR InTERACTIon on MolECUlE ConFoRMATIon STABIlITY AnD CRYSTAl PACKInG oF PolYniTRoCoMPoUnDS

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含能材料 1993年第3期 5-18页

作者： Atovmyan l o Golovina n I Institute of Chemical Physics,Russian Academy of Sciences

In study of polynitrocompounds it is found that a dense crystal mustnot necessarily be constructed from dense molecules,and the main factors affecting thecrystal structure are the electronic structure of their *** correlation betweenthe value of non-bonded intramolecular contact and the magnitude of the respective inter-molecular contact seems to be unusual for this kind of ***-n-oxide and 1, 1, 4, 4,-tetranitrobutanediol-2,3 derivatives weretaken as examples in this *** obtained results concluded that the intramolecularinteraction can stabilize the crystal conformation,while the increase in the intermolecularcontact decreases the crystal density.

关键词： intramolecular interaction polynitrocompounds crystal packing

About Quantum Mechanics without Hamiltonians

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Journal of Modern Physics 2022年第5期13卷 671-681页

作者： Gustavo V. lópez Departamento de Física CUCEI Universidad de Guadalajara Guadalajara Mexico

An extension of Shrödinger’s quantization on the space (x, p), where the Hamiltonian approach is needed, is made on the space (x, v) where the Hamiltonian approach is not needed at all. The purpose of this paper is to give a possible extension of the actual formulation of the Quantum Mechanics, and this is achieved through a function K(x, v, t) which takes the place of the Hamiltonian on the Shrödinger’s equation and has units of energy. This approach allows us to include the quantization of classical velocity depending problems (dissipative) and position depending mass variation problems. Some examples are given.

关键词： Quantization in the Space (x v) Mass Positiondepending Shrödinger’s Equation

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中药水煎液自组装聚集体研究面临的问题初探

药学学报 2024年第1期59卷 94-104页

作者：王琪郭小萌倪乾坤李美景徐睿梁兴杰龚慕辛首都医科大学中医药学院北京100069 中医络病研究北京市重点实验室北京100069 国家纳米科学中心中国科学院纳米科学卓越创新中心中国科学院纳米生物效应与安全性重点实验室北京100190 中国科学院大学北京100086

汤剂是中医临床用药的常用剂型。中药水煎液自组装聚集体(self-assembled aggregates in decoction,SADs)是指在煎煮过程中,中药活性成分受热运动剧烈,在氢键、π-π堆积、疏水相互作用、静电作用等分子作用力下自组装形成的颗粒、凝胶... 详细信息

汤剂是中医临床用药的常用剂型。中药水煎液自组装聚集体(self-assembled aggregates in decoction,SADs)是指在煎煮过程中,中药活性成分受热运动剧烈,在氢键、π-π堆积、疏水相互作用、静电作用等分子作用力下自组装形成的颗粒、凝胶、纤维等聚集体。研究发现SADs普遍存在于中药水煎液中,并可发挥优于有效单体或其物理混合物的生物活性,从成分互作-相态结构角度为揭示中药药效物质基础提供新的思路,现已成为研究热点。本文总结归纳近年相关研究,发现水煎液体系的多分散性、煎煮过程中活性成分相互作用的不稳定性、聚集体自组装规律的未知性、产品物理化学稳定性、纯度与产率等问题在研究中值得关注,并提出解决思路和未来研究展望,以期为SADs的综合开发和临床应用提供参考。

关键词：自组装汤剂相态聚集药效物质

nonlinear Magnetic Response of Superconducting Flux Arrays with Random Pinning

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Chinese Physics letters 1997年第3期14卷 217-220页

作者： ni Jun GU Bing-lin Shuichi Iwata Department of Physics Tsinghua UniversityBeijing 100084 Research into Artifacts Center for EngineeringThe University of TokyoKamaba 4-6-1Meguro-kuTokyo 153Japan

The static nonlinear magnetic response of randomly pinned flux-line lattice in a type-Ⅱ super-conductor has been investigated using variational replica-symmetry-broken method.A peak in the curve of susceptibility as a function of external magnetic field is *** the magnetic field is low,there is a softening in the susceptibility as an effect of pinning potential with nonzero correlation *** some critical magnetic field,the softening changes into *** reaching the maximum in hardening,the susceptibility decreases to its value of piire states with the increase of magnetic field.

关键词： method. field. susceptibility

Solar-driven Co_(2) conversion to methane and methanol using different nanostructured Cu_(2)o-based catalysts modified with Au nanoparticles

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Journal of Energy Chemistry 2024年第4期91卷 287-298页

作者： João Angelo lima Perini lilian D.Moura Torquato Juliana Fde Brito Gustavo A.Andolpho Mateus A.Gonçalves leonardo D.De Angelis lucas D.Germano Susana I.Córdoba de Torresi Teodorico C.Ramalho Maria V.Boldrin Zanoni São Paulo State University(UnESP) Institute of ChemistryRua Prof.Francisco Degni55AraraquaraSP 14800-060Brazil national Institute of Alternative Technologies for Detection Toxicological Evaluation and Removal of Micropollutants and Radioactive Substances(INCT-DATREM)São Paulo State University(UNESP)Institute of ChemistryRua Prof.Francisco Degni55AraraquaraSP 14800-060Brazil laboratory of Molecular Modelling Department of ChemistryNatural Sciences InstituteFederal University of LavrasLavrasMG 37200-900Brazil Department of Chemistry Faculty of ScienceUniversity of Hradec KrálovéHradec Králové50003Czech Republic Instituto de Química Universidade de São PauloAv.Prof.Lineu Prestes 74805508-080São PauloSPBrazil

This work describes the use of Tio_(2)nanotubes-based electrodes(TnT)modified with Cu_(2)o nanostructures and gold nanoparticles for the photoelectroreduction of Co_(2)to produce value-added compounds.A thin layer of polydopamine was used as both an adherent agent and an electron transfer mediator,due to itsπ-conjugated electron *** highest production yield was achieved using a TnT@PDA/nc/Au40%electrode,with Faradaic efficiencies of 47.4%(110.5μM cm^(-2))and 27.8%(50.4μM cm^(-2))for methanol and methane,*** performance of the photoelectrodes was shown to be Cu_(2)o facet-dependent,with cubic structures leading to greater conversion of Co_(2)to methanol(43%)and methane(27%),compared to the octahedral morphology,while a higher percentage of metallic gold on the nanostructured Cu_(2)o surface was mainly important for *** functional theory(DFT)calculations supported these findings,attributing the superior photoelectrocatalytic performance of the TnT@PDA/nc/Au40%electrode for CH4generation to the formation of an oCH3intermediate bonded to Au *** using isotope-labeling and analysis by gas chromatograph-mass(GC-MS)demonstrated that13Co_(2)was the source for photoelectrocatalytic generation of13CH3oH and13CH313CH2oH.

关键词： Cu_(2)o nanocubes Photoelectrocatalysis Polydopamine Co_(2) photoelectroreduction DFT calculations

Adaptive Boundary and Semantic Composite Segmentation Method for Individual objects in Aerial Images

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Computer Modeling in Engineering & Sciences 2023年第9期136卷 2237-2265页

作者： Ying li Guanghong Gong Dan Wang ni li School of Automation Science and Electrical Engineering Beihang UniversityBeijing100191China Shenyuan Honors College Beihang UniversityBeijing100191China State Key laboratory of Virtual Reality Technology and Systems Beijing100191China

There are two types of methods for image *** is traditional image processing methods,which are sensitive to details and boundaries,yet fail to recognize semantic *** other is deep learning methods,which can locate and identify different objects,but boundary identifications are not accurate *** of them cannot generate entire segmentation *** order to obtain accurate edge detection and semantic information,an Adaptive Boundary and Semantic Composite Segmentation method(ABSCS)is *** method can precisely semantic segment individual objects in large-size aerial images with limited GPU *** includes adaptively dividing and modifying the aerial images with the proposed principles and methods,using the deep learning method to semantic segment and preprocess the small divided pieces,using three traditional methods to segment and preprocess original-size aerial images,adaptively selecting traditional results tomodify the boundaries of individual objects in deep learning results,and combining the results of different *** object semantic segmentation experiments are conducted by using the AeroScapes dataset,and their results are analyzed qualitatively and *** experimental results demonstrate that the proposed method can achieve more promising object boundaries than the original deep learning *** work also demonstrates the advantages of the proposed method in applications of point cloud semantic segmentation and image inpainting.

关键词： Semantic segmentation aerial images composite method traditional image processing deep learning

Treatment of landfill leachate by immobilized microorganisms

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Science China Chemistry 2008年第10期51卷 1014-1020页

作者： YE ZhengFang YU HongYan WEn lili ni JinRen Key laboratory of Water and Sediment Sciences of Ministry of Education Department of Environmental EngineeringPeking UniversityBeijing 100871China Key laboratory of Environmental and Urban Sciences Shenzhen Graduate SchoolPeking UniversityShenzhen 518055China

This paper focuses on the outcome and the main performance of the immobilized microbial that treats landfill leachate. Based on the analysis of CoD and ammonia-nitrogen of the influent and effluent, research was done on the high removal efficiency of CoD and ammonium nitrogen by immobilized microbial. The leachate composition was analyzed qualitatively using GC-MS before and after being treated. Biological loading of efficient microbial flora on the carrier was measured by Kjeldahl’s method. Finally, the patterns of immobilized microbe were observed through scanning electron microscopy (SEM). The results showed that in immobilized microorganisms system, the efficiencies of CoD and nitrogen were 98.3% and 99.9%, respectively. There was a great reduction of organic components in effluent. When the immobilized biomass on the carrier was 38 g·l?1 (H2o), the filamentous microorganism was highly developed. There was no inhibitory effect on the nitrobacteria and nitrococcus, when ammonia was over 200 mg·l?1 and nH3 over 150 mg·l?1. At a high organic loading, it still had good nitrification. This paper also compares the performance of immobilized microbial with free microbial under the same condition. The immobilized microbial technology demonstrated better than the latter in all aspects.

关键词： immobilization microbial performance treatment landfill leachate

Mathematical analysis of SoFC based on co-ionic conducting electrolyte

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Acta Mechanica Sinica 2013年第3期29卷 388-394页

作者： Ke-Qing Zheng Meng ni Qiong Sun li-Yin Shen Building Energy Research Group Department of Building and Real Estate The Hong Kong Polytechnic University

In co-ionic conducting solid oxide fuel cell （SoFC）, both oxygen ion （o2） and proton （H＋） can transport through the electrolyte, generating steam in both the an-ode and cathode. Thus the mass transport phenomenon in the electrodes is quite different from that in conventional SoFC with oxygen ion conducting electrolyte （o-SoFC） or with proton conducting electrolyte （H-SoFC）. The generation of steam in both electrodes also affects the concentration over-potential loss and further the SoFC performance. However, no detailed modeling study on SoFCs with co-ionic electrolyte has been reported yet. In this paper, a new mathematical model for SoFC based on co-ionic electrolyte was developed to predict its actual performance considering three major kinds of overpotentials. ohm＇s law and the Butler-Volmer formula were used to model the ion conduction and electrochemical reactions, respectively. The dusty gas model （DGM） was employed to simulate the mass transport processes in the porous electrodes. Parametric simulations were performed to investigate the effects of proton transfer number （tH） and current density （jtotal） on the cell performance. It is interesting to find that the co-ionic conducting SoFC could perform better than o-SoFC and H-SoFC by choosing an appropriate proton transfer number. In addition, the co-ionic SoFC shows smaller difference between the anode and cathode concentration overpotentials than o-SoFC and H-SoFC at certain t H values. The results could help material selection for enhancing SoFC performance.

关键词： Co-ionic electrolyte Proton transport number Concentration overpotential Mass transport Model