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Locally Resonant Gaps of Phononic Beams Induced by Periodic Arrays of Resonant Shunts

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Chinese Physics Letters 2011年第9期28卷 166-169页

作者： CHEN Sheng-Bing wen ji-Hong WANG Gang HAN xiao-Yun wen xi-Sen Laboratory of Science and Technology on Integrated Logistics Support National University of Defense TechnologyChangsha 410073

Periodic arrays of shunted piezoelectric patches are employed to control the propagation of elastic waves in phononic *** piezo-patch is connected to a single resistance-inductance-capacitance shunting ***,the resonances of the shunting circuits will produce locally resonant gaps in the phononic ***,the existence of locally resonant gaps induced by resonant shunts has not been clearly proved by experiment so *** this work,the locally resonant gap in a piezo-shunted phononic beam is investigated theoretically and verified by *** results prove that resonances of shunting circuits can produce locally resonant gaps in phononic beams.

关键词： experiment resonant locally

Bifunctional Mn-doped CoSe_(2) nanonetworks electrode for hybrid alkali/acid electrolytic H_(2) generation and glycerol upgrading

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Journal of Energy Chemistry 2022年第9期31卷 424-431,I0012页

作者： Linfeng Fan Yaxin ji Genxiang Wang Zhifang Zhang Luocai Yi Kai Chen xi Liu Zhenhai wen CAS Key Laboratory of Design and Assembly of Functional Nanostructures and Fujian Key Laboratory of NanomaterialsFujian Institute of Research on the Structure of MatterChinese Academy of SciencesFuzhou 350002FujianChina School of Chemistry and Chemical Engineering Yulin UniversityYulin 719000ShaanxiChina University of Chinese Academy of Science Beijing 100049China College of Chemistry and Materials Science Fujian Normal UniversityFuzhou 350007FujianChina

Electrolytic water splitting,as a promising route to hydrogen(H_(2))production,is still confronted with the sluggish anodic oxygen evolution reaction(OER)and its less value-added O2 ***,we report a bifunctional electrode fabricated by in situ growth of Mn-doped CoSe_(2)nanonetworks on carbon fiber cloth(Mn-CoSe_(2)/CFC),which shows attractive electrocatalytic properties toward glycerol oxidation reaction(GOR)in alkali and hydrogen evolution reaction(HER)in acid.A flow alkali/acid hybrid electrolytic cell(fA/A-hEC)was then developed by coupling anodic GOR with cathodic HER with the Mn-CoSe_(2)/CFC bifunctional *** fA/A-hEC enables a rather low voltage of 0.54 V to achieve 10 mA cm^(-2),and maintain long-term electrolysis stability over 300-h operation at 100 mA cm^(-2)with Faraday efficiencies of over 99%for H_(2)and 90%for formate *** designed bifunctional electrode in such innovative fA/A-hEC device provides insightful guidance for coupling energy-efficient hydrogen production with biomass upgradation.

关键词： Mn-doped CoSe_(2)nanonetworks Glycerol upgrading electrooxidation Hydrogen production Bifunctional electrocatalytic electrode Hybrid flow alkali/acid electrolyzer

Alternative industrial carbon emissions benchmark based on input-output analysis

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Frontiers of Earth Science 2016年第4期10卷 731-739页

作者： Mengyao HAN xi ji Institute of Geographic Sciences and Natural Resources Research Chineses Academy of Sciences Beijing 100871 China College of Engineering Peking University Beijing 100871 China School of Economics Peking University Beijing 100871 China

Some problems exist in the current carbon emissions benchmark setting systems. The primary con- sideration for industrial carbon emissions standards highly relate to direct carbon emissions （power-related emissions） and only a portion of indirect emissions are considered in the current carbon emissions accounting processes. This practice is insufficient and may cause double counting to some extent due to mixed emission sources. To better integrate and quantify direct and indirect carbon emissions, an embodied industrial carbon emissions benchmark setting method is proposed to guide the establishment of carbon emissions benchmarks based on input-output analysis. This method attempts to link direct carbon emissions with inter-industrial economic exchanges and systematically quantifies carbon emissions embodied in total product delivery chains. The purpose of this study is to design a practical new set of embodied intensity-based benchmarks for both direct and indirect carbon emissions. Beijing, at the first level of carbon emissions trading pilot schemes in China, plays a significant role in the establish- ment of these schemes and is chosen as an example in this study. The newly proposed method tends to relate emissions directly to each responsibility in a practical way through the measurement of complex production and supply chains and reduce carbon emissions from their original sources. This method is expected to be developed under uncertain internal and external contexts and is further expected to be generalized to guide the establish- ment of industrial benchmarks for carbon emissions trading schemes in China and other countries.

关键词： emissions trading scheme benchmarking,carbon emissions input-output analysis

Scalable peer-to-peer resource discovering scheme for wireless self-organized networks

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The Journal of China Universities of Posts and Telecommunications 2009年第2期16卷 47-52,57页

作者： LI xi ji Hong Key Laboratory of Universal Wireless Communications Minisa-y of Education Beijing University of Posts and Telecommunications Beijing 100876 China

Peer-to-peer technologies have attracted increasing research attention with fruitful protocols and applications proposed for wired networks. As to mobile environments, there are currently no mature deployments. A novel resource managing and discovering protocol, Cheer, is proposed to realize scalable and effective peer-to-peer lookup in wireless self-organized networks. Cheer resolves the topologies mismatch problem between peer-to-peer overlay networks and actual nodes distribution, allowing for frequent nodes membership changes. With specially designed resource storage table, Cheer also supports multikey and fuzzy lookup. Its hybrid architecture and improved routing scheme based on small-world theory may realize effective lookup routing. Theoretical analysis and simulation results both prove that Cheer makes using peer-to-peer applications in large-scale self-organized mobile networks feasible and promising.

关键词： peer-to-peer small-world resource discovering

Sulfur dioxide sensing properties of MOF-derived ZnFe_(2)O_(4) functionalized with reduced graphene oxide at room temperature

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Rare Metals 2021年第6期40卷 1604-1613页

作者： Lan-Juan Zhou xi-xi Zhang wen-Yuan Zhang College of Control Science and Engineering China University of Petroleum(East China)Qingdao 266580China United Microelectronics Center Chongqing 401332China

In this paper,ZnZnFe_(2)O_(4) nanorods were prepared using Zn/Fe metal organic framework(MOF)as precursors,and ZnZnFe_(2)O_(4)/reduced graphene oxide(rGO)was prepared by hydrothermal *** morphology and composition of the ZnZnFe_(2)O_(4)/rGO nanocomposite were characterized,and the results showed that the MOF-derived ZnZnFe_(2)O_(4) nanorods are uniformly modified on the surface of *** ZnZnFe_(2)O_(4)/rGO nanocomposite exhibits better SO_(2) gas sensing performance than the single ZnZnFe_(2)O_(4) nanorods at room *** sensing characteristics of single ZnZnFe_(2)O_(4) film sensor,single rGO film sensor and ZnZnFe_(2)O_(4)/rGO composite film sensor at SO_(2)gas concentration(1×10^(-6)-100×10^(-6))were *** response of ZnZnFe_(2)O_(4)/rGO composite sensor can reach 18.32%at room *** with single ZnZnFe_(2)O_(4) and rGO film sensors,the ZnZnFe_(2)O_(4)/rGO composite sensor has better transient response,good sensitivity and *** this work,the improvement of the sensor performance is not only due to the p-n heterostructure between ZnZnFe_(2)O_(4) nanorods and rGO nanosheets,but also to the excellent electrical properties of *** provides a new idea for the detection of SO_(2) at room temperature.

关键词： Ternary metal oxide ZnFe_(2)O_(4)nanorods Reduced graphene oxide SO_(2)gas sensor

A computational model for capturing the distinct in-and out-of-plane response of lipid membranes

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Acta Mechanica Sinica 2021年第1期37卷 138-144,I0004页

作者： Pinjing wen xi Wei Yuan Lin Institute of Semiconductor Manufacturing Research Shenzhen UniversityShenzhen518060China College of Physics and Optoelectronic Engineering Shenzhen UniversityShenzhen518060China Department of Mechanical Engineering The University of Hong KongHong KongSARChina

A computational framework was developed to capture the combined fluid-and solid-like behavior of lipid membranes in a unified ***,the in-plane diffusion of lipid molecules and the associated evolution of membrane tension were explicitly taken into account in the *** addition,the out-of-plane movement induced bending and shearing of membrane,along with its thermal undulations caused by bombardment of medium molecules,were also *** capability and validity of this approach were demonstrated by simulating the enforced deformation and shape fluctuations of a lipid vesicle under a variety of testing conditions as well as their comparison with corresponding theoretical *** model could serve a useful platform for investigating processes such as cell spreading and division where morphology evolution of the membrane and transport of lipids/transmembrane proteins are known to play key roles.

关键词： Cell membrane Thermal undulations Lipid diffusion Finite element method

Chemisorption-Induced Resonance Frequency Shift of a Microcantilever

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Chinese Physics Letters 2012年第5期29卷 193-196页

作者： ZHANG ji-Qiao FENG xi-Qiao HUANG Gan-Yun YU Shou-wen Faculty of Civil and Transportation Engineering Guangdong University of TechnologyGuangzhou 510006 AML Department of Engineering MechanicsTsinghua UniversityBeijing 100084 Department of Mechanics School of Mechanical EngineeringTianjin UniversityTianjin 300072

The autonomy and property of atoms/molecules adsorbed on the surface of a microcantilever can be probed by measuring its resonance frequency shift due to *** resonance frequency change of a cantilever induced by chemisorption is theoretically studied. Oxygen chemisorbed on the Si(100) surface is taken as a representative *** demonstrate that the resonant response of the cantilever is mainly determined by the chemisorption-induced bending stiffness variation,which depends on the bond configurations formed by the adsorbed atoms and substrate *** study is helpful for optimal design of microcantilever-based sensors for various applications.

关键词： cantilever adsorbed sorption

Tuning the Learning Rate for Stochastic Variational Inference

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Journal of Computer Science & Technology 2016年第2期31卷 428-436页

作者： xi-Ming Li ji-Hong Ouyang College of Computer Science and Technology Jilin University Changchun 130000 China Key Laboratory of Symbolic Computation and Knowledge Engineering of Ministry of Education Jilin University Changchun 130000 China

Stochastic variational inference （SVI） can learn topic models with very big corpora. It optimizes the variational objective by using the stochastic natural gradient algorithm with a decreasing learning rate. This rate is crucial for SVI; however, it is often tuned by hand in real applications. To address this, we develop a novel algorithm, which tunes the learning rate of each iteration adaptively. The proposed algorithm uses the Kullback-Leibler （KL） divergence to measure the similarity between the variational distribution with noisy update and that with batch update, and then optimizes the learning rates by minimizing the KL divergence. We apply our algorithm to two representative topic models： latent Dirichlet allocation and hierarchical Dirichlet process. Experimental results indicate that our algorithm performs better and converges faster than commonly used learning rates.

关键词： stochastic variational inference online learning adaptive learning rate topic model

Influence of sperm morphology on pregnancy outcome and offspring in in vitro fertilization and intracytoplasmic sperm injection:a matched case-control study

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Asian Journal of Andrology 2021年第4期23卷 421-428页

作者： wen-Jun Zhou Chuan Huang Su-Hua jiang xi-Ren ji Fei Gong Li-Qing Fan wen-Bing Zhu Institute of Reproductive and Stem Cell Engineering Basic Medicine CollegeCentral South UniversityChangsha 410008China Reproductive and Genetic Hospital of CITIC-xiangya Changsha 410008China Clinical Research Center for Reproduction and Genetics in Hunan Province Changsha 410008China

Sperm morphology was once believed as one of the most predictive indicators of pregnancy outcome in assisted reproductive technology(ART).However,the impact of teratozoospermia on in vitro fertilization(IVF)/intracytoplasmic sperm injection(ICSI)outcomes and its offspring remains *** order to evaluate the influence of teratozoospermia on pregnancy outcome and newborn status after IVF and ICSI,a retrospective study was *** was a matched case-control study that included 2202 IVF cycles and 2574 ICSI cycles and was conducted at the Reproductive and Genetic Hospital of CITIC-xiangya in Changsha,China,from June 2013 to June *** were divided into two groups based on sperm morphology:teratozoospermia and normal sperm *** pregnancy outcome and newborn outcome were *** results indicated that couples with teratozoospermia had a significantly lower optimal embryo rate compared to those with normal sperm morphology in IVF(P=0.007),while there were no statistically significant differences between the two groups in terms of the fertilization rate,cleavage rate,implantation rate,and pregnancy rate(all P>0.05).Additionally,teratozoospermia was associated with lower infant birth weight in multiple births after *** regard to ICSI,there was no significant difference in both pregnancy outcome and newborn outcome between the teratozoospermia and normal groups(both P>0.05).Furthermore,no increase in the risk of birth defects occurred in the teratozoospermia group after IVF/***,we believe that teratozoospermia has limited predictive value for pregnancy outcomes in IVF/ICSI,and has little impact on the resulting offspring if multiple pregnancy is avoided.

关键词： in vitro fertilization intracytoplasmic sperm injection newborn outcome pregnancy outcome teratozoospermia