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Exact Time-Dependent Wave functions of a confined Time-Dependent Harmonic Oscillator with Two Moving Boundaries

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communications in Theoretical Physics 2009年第11期52卷 820-824页

作者： c.f.Lo Institute of Theoretical Physics and Department of Physics The Chinese University of Hong Kong

By applying the standard analytical techniques of solving partial differential equations, we have obtained the exact solution in terms of the fourier sine series to the time-dependent Schrodinger equation describing a quantum one-dimensional harmonic oscillator of time-dependent frequency confined in an infinite square well with the two walls moving along some parametric trajectories. Based upon the orthonormal basis of quasi-stationary wave functions, the exact propagator of the system has also been analytically derived. Special eases like （i） a confined free particle, （ii） a confined time-independent harmonic oscillator, and （iii） an aging oscillator are examined, and the corresponding time- dependent wave functions are explicitly determined. Besides, the approach has been extended to solve the case of a confined generalized time-dependent harmonic oscillator for some parametric moving boundaries as well.

关键词： infinite square well harmonic oscillator moving boundaries fourier series

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化学竞赛试题选编(附答案)

化学教学 1981年第1期 44-47页

作者： c.f Protheroe,吴琦广州市执信中学美

下列五组试题译自美国《化学》(chemistry)杂志的“The Whiz Quiz”(原意“优等生测验”)栏。优等生必须正确地解答每组中的各题;答错三题以下者属于良;低于上项标准者属于不及格。请查阅各组答案,改正错误,争取优良成绩。在下列各题的... 详细信息

下列五组试题译自美国《化学》(chemistry)杂志的“The Whiz Quiz”(原意“优等生测验”)栏。优等生必须正确地解答每组中的各题;答错三题以下者属于良;低于上项标准者属于不及格。请查阅各组答案,改正错误,争取优良成绩。在下列各题的四个答案中,只有一个是正确的,其余三个都是错误的。

关键词：毫米水银柱非极性键立方厘米原子量电离能竞赛试题

Biofuel-driven trigeneration systems for non-residential building applications:A holistic assessment from the energy,environmental and economic perspectives

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Building Simulation 2023年第4期16卷 557-576页

作者： K.f.fong c.K.Lee Division of Building Science and Technology College of EngineeringCity University of Hong KongTat Chee AvenueKowloonHong KongChina

In the metropolises,it is unlikely to use merely solar and wind energy to pursue zero carbon building ***,it would become possible if biofuel-driven trigeneration systems(BDTS)are *** is thus essential to assess the application opportunity of BDTS in a holistic *** this study,BDTS offered definite primary energy saving of up to 15%and carbon emissions reduction of at least 86%in different types of non-residential buildings as compared to the conventional *** 24/7 operation for the hotel and hospital buildings,the corresponding BDTS could even achieve zero carbon *** the BDTS primed with compression-ignition internal combustion engine were not economically viable even in running cost due to the high local biodiesel price *** BDTS primed with spark-ignition engine and fueled by biogas,however,would have economic merit when carbon price was considered for the conventional systems that fully utilize fossil *** of carbon tax and social cost could have the payback ceilings of 8 years and 2 years respectively for most of building ***,the results could reflect the application potential of BDTS for non-residential buildings,leading the pathway to carbon neutrality for sustainable sub-tropical cities.

关键词： trigeneration biofuel dynamic simulation carbon tax social cost economic analysis

The Kirkendall effect on erosion resistance of chrome-coated 25cr3Mo2WNiV and 30SiMn2MoV gun barrel steels

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Journal of Materials Science & Technology 2024年第10期177卷 246-255页

作者： c.H.Dou P.f.Jin c.Z.Wang J.J.Li c.Zhang J.f.Huang c.Zhang Key Laboratory for Advanced Materials Processing State State Key Laboratory for Advanced Metals and MaterialsUniversity of Science and Technology BeijingBeijing 100083China National Joint Engineering Research center for Abrasion control and Molding of Metal Materials School of Materials Science and EngineeringHenan University of Science and TechnologyLuoyang 471003China

This study aimed to investigate the erosion behavior and mechanism of a newly developed 25cr3Mo2WNiV steel with a chrome coating using promoted ignition combustion *** erosion threshold pressure and temperature of the chrome-coated 25cr3Mo2WNiV steel were determined to be 0.2 MPa and 254.3 K higher than those of traditional chrome-coated 30SiMn2MoV ***,Kirkendall voids and inter-diffusion between the cr coating and matrix were first observed before *** improved erosion resistance of the chrome-coated 25cr3Mo2WNiV steel was attributed to the suppression of the Kirkendall effect,which minimized heat generation at the cr/matrix interface by pre-venting oxygen diffusion and reducing oxygen affinity.

关键词： Erosion resistance Kirkendall effect cr coating Gun steel

New Nanocomposite Materials by Incorporation of Nanocrystalline TiO_2 Particles into Polyaniline conductive films

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Journal of Materials Science & Technology 2014年第5期30卷 449-454页

作者： f.J.feliciano O.c.Monteiro Department of chemistry and Biochemistry and cQB Faculty of SciencesUniversity of LisbonCampo Grande1749-016 LisbonPortugal

This work is focused on the combination of two building-blocks, nanocrystalline TiO2 particles and polyaniline conductive films （PAni）. The preparation of new nanostructured composite materials, displaying electron- and proton-conductive properties, to be used for the fabrication of new and superior energy storage devices was envisaged. The semiconducting TiO2 nanoparticles were obtained by means of a hydrothermal route. The PAni films were prepared on glassy carbon electrodes by electrochemical polymerization, under potential dynamic conditions. After characterization by X-ray diffraction, transmission electron microscopy or scanning electron microscopy and electrochemical techniques, the nanocrystalline particles were immobilized in the polymer matrix. The incorporation of the TiO2 was achieved using two distinct approaches： during the polymer growth or by deposition over previously prepared PAni films. The results demonstrate that the PAni morphology depends on the experimental conditions used during the polymer growth. After TiO2 immobilization, the best electrochemical response was obtained for the nanocomposite structure produced through the TiO2 incorporation after the PAni film synthesis. The modified electrodes were structurally and morphologically characterized and their electro-catalytic activity towards the hydrogen evolution reaction was analyzed. A new electrochemical performance related with the oxidation of molecular hydrogen entrapped in the PAni-TiO2 matrix was observed for the modified electrode after TiO2 incorporation. This behavior can be directly associated with the synergetic combination of the TiO2 and PAni, and is dependent on the amount of the semiconductor.

关键词： PolyaniHne (PAni) Nanosized TiO2 Nanocomposites Hydrogen trapping

Identification of Hammerstein-Wiener model with discontinuous input nonlinearity

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Science china(Information Sciences) 2023年第12期66卷 33-47页

作者： A.BROURI f.Z.EL MANSOURI f.Z.cHAOUI c.ABDELAALI f.GIRI ENSAM Moulay Ismail University ENSAM University Mohammed V Normandie Universite

This paper deals with the identification of Hammerstein-Wiener models with an irregular function in the input block. These models comprise a set of linear segments. The linear time invariant(LTI) block may be parametric or nonparametric. The nonlinearity of the output can be any continuous function of arbitrary shape; it is not necessarily assumed to be invertible. Subsequently, sine inputs will be used to identify the system parameters. first, the output nonlinearity is determined by filtering the system output and varying the phase of a given reference sine signal; second, the parameters of the linear block can be determined for any frequency; and finally, the input nonlinearity can be obtained by changing the offset and amplitude of the input sine signal.

关键词： nonlinear systems nonlinear systems identification Hammerstein-Wiener models discontinuous nonlinearities hard nonlinearities

The role of rhizobacteria in rice plants: Growth and mitigation of toxicity

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Journal of Integrative Agriculture 2018年第12期17卷 2636-2647页

作者： Marcela c.f Rêgo Aline f cardoso Thayná da c.ferreira Marta c c de filippi Telma f V Batista Rafael G Viana Gisele B da Silva Plant Protection Laboratory Institute of Agrarian Sciences Federal Rural University of Amazon Phytopathology Laboratory Brazilian Enterprise for Agricultural Research-Rice and Beans

Allelopathic compounds reduce the growth and productivity of upland rice plants, especially in consecutive plantations. The rhizobacteria Pseudomonas fluorescens BRM-32111 and Burkholderia pyrrocinia BRM-32113 have been recorded as growth promoters in rice. This study was developed to understand the effect of the application of rhizobacteria on upland rice plants in consecutive plantations. Experiments were conducted in a completely randomized design with four replications of four treatments: rice seed inoculated with P. fluorescens BRM-32111, rice seed inoculated with B. pyrrocinia BRM-32113(both sown on soil with rice residue), non-inoculated plants sown on soil with rice residue(control with residue(WR)), and non-inoculated plants on soil with no residue(NR). Roots and seedling growth were adversely affected by allelopathic compounds in control WR plants. Plants inoculated with rhizobacteria P. fluorescens BRM-32111 or B. pyrrocinia BRM-32113 induced an increase of 88% in biomass, 3% in the leaf area, 40% in length, 67% in root biomass, 21% in chlorophyll a, 53% in chlorophyll(a+b), 50% in rate of carbon assimilation(A), 227% in A/rubisco carboxylation efficiency(ci) and 63% in water use efficiency(WUE) compared to control WR plants. These results indicate that rhizobacteria P. fluorescens BRM-32111 and B. pyrrocinia BRM-32113 increase the tolerance of rice plants to stress from allelochemicals. There are possible practical agricultural applications of these results for mitigating the effects of environmental allelochemistry on upland rice.

关键词： allelopathy B.pyrrocinia P.fluorescens rhizobacteria rice

SOME NEW cLASSES Of ALMOST PERIODIc.fUNcTIONS

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chinese Annals of Mathematics,Series B 1989年第2期10卷 200-213页

作者： c.J.f.UPTON University of Melbourne Parkville Victoria 3052 Australia

In this paper classes of almost periodic.functions are formed whlch lie between those established by W. Stepanoff and by H. Burkill.

关键词： cLASSES everywhere adding proof whenever 妇功 false apply Lebesgue 即夕

Rare cause of ileus in the mesenteric cavity of terminal ileum:A report of three cases

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World Journal of Gastroenterology 2006年第33期12卷 5422-5423页

作者： A Tekin f Aksoy c Vatansev T Kücükkartallar Department of General Surgery Selcuk University Meram Medical Faculty Akyoku■ KonyaTurkey

Internal herniation is one of the rare reasons of intestineclog, which is hard to diagnose and usually needs anurgent surgical treatment. We report 3 patients withinternal herniation in the mesenteric cavity of theterminal ileum. Besides intestinal congestion, they alsohad peritoneal irritation. Laparotomy revealed thatherniation caused disorder in nutrition of the intestineand necrosis. The patients underwent subtotal smallintestine resection and were discharged 10, 12 and 14 dafter operation.

关键词： Intestinal herniation Ileus Therapy