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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2011年第3期12卷 232-237页

作者： Ke TANG Tian LEI Xiao-gang lin tao JIN Yu ZHANG Institute of Refrigeration and Cryogenics Zhejiang University Hangzhou 310027 China

Gas-liquid coupling oscillation is a novel approach to reducing the resonant frequency and to elevating the pressure amplitude of a thermoacoustic *** a thermoacoustic engine is used to drive low-frequency pulse tube refrigerators,the frequency matching between the thermoacoustic engine and the refrigerator plays an important *** on an acoustic-electric analogy,a lumped parameter model is proposed to estimate the resonant frequency of a standing-wave thermoacoustic engine with gas-liquid coupling ***,a simplified lumped parameter model is also developed to reduce the computation *** resonant frequency dependence on the mean pressure,the gas space volume,and the water column length is computed and *** impact of different working gases on the resonant frequency is also *** effectiveness of the models is validated by comparing the computed results with the experimental data of the gas-liquid coupling oscillation *** increase in the mean working pressure can lead to a rise in the resonant frequency,and a lower resonant frequency can be achieved by elongating the liquid *** comparison with nitrogen and argon,carbon dioxide can realize a lower frequency due to a smaller specific heat ratio.

关键词： Thermoacoustic engine Gas-liquid coupling oscillation Acoustic-electric analogy Resonant frequency

Facile access to chiral 4-substituted chromanes through Rh-catalyzed asymmetric hydrogenation

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Chinese Chemical Letters 2020年第7期31卷 1859-1862页

作者： lin tao Qingyang Zhao Xumu Zhang Xiu-Qin Dong Key Laboratory of Biomedical Polymers Engineering Research Centre of Organosilicon Compounds&MaterialsMinistry of EducationCollege of Chemistry and Molecular SciencesWuhan UniversityWuhan 430072China Department of Chemistry and Shenzhen Grubbs Institute Southern University of Science and TechnologyShenzhen 518055China School of Pharmaceutical Sciences(Shenzhen) Sun Yat-sen UniversityShenzhen 518107China

Rh/ZhaoPhos-catalyzed asymmetric hydroge nation of a series of(E)-2-(chro man-4-ylidene)acetates was successfully developed to prepare various chiral 4-substituted chromanes with high yields and excellent enantioselectivities(up to 99%yield,98%ee).Moreover,the gram-scale hydrogenation could be performed well in the presence of 0.02 mol%catalyst loading(TON=5000),the hydrogenation product was easily converted to access other important compounds,which demonstrated the synthetic utility of this asymmetric catalytic methodology.

关键词： Chiral 4-substituted chromanes Asymmetric hydrogenation Excellent enantioselectivity Gram-scale synthesis Bisphosphine-thiourea ligand

Intensive construction technology for urban underground parking shaft

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Frontiers of Structural and Civil Engineering 2024年第11期18卷 1649-1662页

作者： Hong JIANG Xian LIU Heli BAO Jinfeng BI tao lin Tengfei HE Shanghai Urban Construction Design&Research Institute Shanghai 200125China College of Civil Engineering Tongji UniversityShanghai 200092China

As urban construction continues to develop and automobile ownership rises,parking shortages in cities have become increasingly *** the limited availability of land resources,conventional underground garages and parking buildings no longer suffice to meet the growing demand for parking *** address this dilemma,underground parking shaft(UPS)has emerged as a highly regarded *** study provides an overview of the layout scheme,structural design approaches,and construction techniques for UPS,focusing on the characteristics of intensive construction demonstrated in the project located in the Jianye District of *** to conventional vertical shaft garage construction methods,this assembly parking shaft offers advantages such as a smaller footprint,higher prefabrication rate,shorter construction period,and reduced environmental *** presents an efficient approach for the intensive construction of urban underground spaces,particularly in areas with limited land and complex environments,showing promising prospects for widespread application.

关键词： intensive construction parking shaft assembly underground garage

Effect of coarse TiN inclusions and microstructure on impact toughness fluctuation in Ti micro-alloyed steel

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Journal of Iron and Steel Research International 2018年第10期25卷 1043-1053页

作者： tao Liu Mu-jun Long Deng-fu Chen Hua-mei Duan lin-tao Gui Sheng Yu Jun-sheng Cao Hua-biao Chen He-lin Fan State Key Laboratory of Coal Mine Disaster Dynamics and Control College of Materials Science and Engineering Chongqing University Chongqing 400044 China Chongqing Key Laboratory of Vanadium-Titanium Metallurgy and New Materials Chongqing University Chongqing 400044 China

Toughness is an important property for steels used in engineering applications. However, recent toughness testing has shown the existence of a significant fluctuation in toughness in a single rolled plate of titanium micro-alloyed steel. The underlying causes of this fluctuation were investigated by fractography, analysis of microstructure and measurement of inclusions. Coarse and distributed TiN inclusions were responsible for the toughness variation, as they tended to act as the potential cleavage initiators to form micro-cracks. From a calculation of the local fracture stress, the critical size of coarse TiN inclusions for dominating micro-crack propagation was 4.93 μm, and similarly that of ferrite grains was 36.6μm. Under current casting and thermo-mechanically controlled processing schedules, the toughness fluctuation of rolled steel plates can be primarily attributed to the fraction of coarse TiN inclusions larger than 5μm. A corresponding relationship between impact energy and the proportion of coarse TiN inclusions was established. Finally, a normalizing treatment was applied to refine the ferrite grains of rolled steel plates. Despite the presence of coarse TiN inclusions, this refinement in ferrite grains minimized the toughness fluctuation and improved the uniformity of the impact properties of the steel plates.

关键词： Impact toughness fluctuation Ti micro-alloyed steel Cleavage fracture Coarse TiN inclusion Grain refinement

The Nonlinear Singularly Perturbed Initial Boundary Value Problems of Nonlocal Reaction Diffusion Systems

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Acta Mathematicae Applicatae Sinica 2006年第2期22卷 277-286页

作者： Jia-qi Mo Wan-tao lin Department of Mathematics Huzhou Teachers College Huzhou 313000 China Division of Computational Science E-Institutes of Shanghai Universities at SJTU Shanghai 200240 China LASC Institute of Atmosheric Physics Chinese Academy of Sciences Beijing 100029 China

In this paper the singularly perturbed initial boundary value problems for the nonlocal reaction diffusion system are considered. Using the iteration method and the comparison theorem, the existence and its asymptotic... 详细信息

关键词： Reaction diffusion system singular perturbation initial boundary value problem

Photomorphogenesis——from One Photoreceptor to 14：40 Years of Progress

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Molecular Plant 2012年第3期5卷 531-532页

作者： Winslow R. Briggs Chen-tao lin 机构不详

In September of 1971, a group of plant biologists assembled for two weeks in Eretria on the Greek island of Euboea （Evia） under the sponsorship of NATO and the University of Athens to participate in a NATO school devoted to studies of role of light signaling in plants. Embedded in the conference was a mini-symposium entitled ＇Annual European Symposium on Photomorphogenesis＇. The generous funding supported grad- uate-student and postdoctoral-fellow participation in the symposium.

关键词： Photomorphogenesis Photoreceptor Progress

Drinking water biotic safety of particles and bacteria attached to fines in activated carbon process

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Frontiers of Environmental Science & Engineering 2007年第3期1卷 280-285页

作者： CHEN Wei lin tao WANG Leilei College of Environmental Science and Engineering Hohai UniversityNanjing 210098China

In this paper,the drinking water biotic safety of particles and bacteria attached to fines in activated carbon process was investigated by actual treatment process and advanced treatment pilot trial with granular activated *** the experiment,the particles were detected by IBR particle calculating instrument,the activated carbon fines were counted on the basis of the most probable number(MPN)with a microscope,the total number of bacteria was analyzed between the conventional agar culture medium and the one with R2A,and the bacteria attached to activated carbon fines was resolved by the homogenization *** experi-mental results showed that the average total number of parti-cles was 205 CNT/mL in the activated carbon effluent during a filter cycle,of which the number of particles with sizes>2μm was 77 CNT/mL more than the present particle con-trol criterion of the American drinking water product standard(50 CNT/mL).The backwash of low density and long dura-tion lowered particle number in the *** MPN of activated carbon fines in the effluent was between 400 and 600 CNT/L,which accounted for less than 5‰ of the total particles from activated carbon filtration for a poor relative level(R^(2)=0.34).The microorganisms in activated carbon effluent consisted mostly of heterotrophic bacillus and the total bacteria number was five times as high as that of the inflow,*** effluent from sand *** actual bacteria number may be truly indicated by the detection technique with R2A culture medium compared with the traditional agar *** inactivation efficiency of bacteria attached to activated carbon fines was less than 40%under 1.1 mg/L of chlorine contacting for 40 *** showed that the particles and bacteria attached to activated carbon fines may influence drinking water biotic safety,and that the effective control measures need to be further investigated.

关键词： drinking water granular activated carbon particles activated carbon fines bacteria disinfection

Mechanisms of HIV envelope-induced T lymphocyte apoptosis

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Virologica Sinica 2010年第5期25卷 307-315页

作者： Zhi-tao WAN Xu-lin CHEN State Key Laboratory of Virology Wuhan Institute of Virology Chinese Academy of Sciences Wuhan 430071China

Infection by the human immunodeficiency virus （HIV） is characterized by a progressive depletion of CD4 T lymphocytes, which leads to dysfunction of the immune system. Although a variety of mechanisms may contribute to the gradual T cell decline that occurs in H/V-infected patients, abnormal apoptosis of infected or bystander T lymphocytes is an important event leading to immunodeficiency. The HIV envelope glycoprotein plays a crucial role in HIV associated apoptosis through both death receptor-mediated and mitochondria-dependent pathways. This review summarizes current knowledge of Env-mediated T lymphocyte apoptosis.

关键词： HIV Envelope glycoprotein T lymphocyte Apoptosis

A Class of Nonlinear Singularly Perturbed Problems for Reaction Diffusion Equations with Boundary Perturbation

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Acta Mathematicae Applicatae Sinica 2006年第1期22卷 27-32页

A class of nonlinear singularly perturbed problems for reaction diffusion equations with boundary perturbation are considered. Under suitable conditions, the asymptotic behavior of solution for the initial boundary va... 详细信息

关键词： Nonlinear reaction diffusion singular perturbation ,boundary perturbation

Genetic algorithm for autonomic joint radio resource management in end-to-end reconfigurable systems

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The Journal of China Universities of Posts and Telecommunications 2008年第1期15卷 11-17页

作者： ZENG Xian MA tao lin Yue-wei FENG Zhi-yong Key Laboratory of Universal Wireless Communications Beijing University of Posts and Telecommunications Ministry of Education Beijing 100876 China

This article presents the genetic algorithm （GA） as an autonomic approach for the joint radio resource management （JRRM） amongst heterogeneous radio access technologies （RATs） in the end-to-end reconfigurable systems. The joint session admission control （JOSAC） and the bandwidth allocation are combined as a specific decision made by the operations of the genetic algorithm with certain advisable modifications. The proposed algorithm is triggered on the following two conditions When a session is initiated, it is triggered for the session to camp on the most appropriate RAT and select the most suitable bandwidth for the desired service. When a session terminates, it is also used to adjust the distribution of the ongoing sessions through the handovers. This will increase the adjustment frequency of the JRRM controller for the best system performance. Simulation results indicate that the proposed autonomic JRRM scheme not only effectively reduces the handover times, but also achieves well trade-off between the spectrum utility and the blocking probability.

关键词： genetic algorithm handover heterogeneous network,joint radio resource management reconfigurability