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International Journal of Minerals,Metallurgy and Materials 2011年第2期18卷 165-168页

作者： Xiang-jie Wang Jian-zhong Cui Yu-bo Zuo zhi-hao Zhao Hai-tao Zhang Key Lab of Electromagnetic Processing of Materials （Ministry of Education） Northeastern University Shenyang 110004 China

To improve the quality of 7050 aluminum alloy ingots, low-frequency electromagnetic （LFE） field was applied during the conventional hot-top casting process. Macrostructures and microstructures of the ingots by the conventional and LFE hot-top casting processes were studied. The experimental results show that when the LFE field is turn off during the hot-top casting process, cold folding appears, and the as-cast structure becomes very coarse. Additionally, the thickness of the shell zone is much thinner during the low-frequency electromagnetic hot-top casting process than that during the conventional hot-top casting process. Some reasons for low-frequency electromagnetic field improving the surface quality, refining the structure of the ingot, and minimizing the thickness of the shell zone have been studied.

关键词： aluminum alloys solidification surface quality electromagnetic field

Intermediate phase-assisted growth of CsPbBr_(3) for high performance of carbon-based perovskite solar cells

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Rare Metals 2024年第5期43卷 2222-2229页

作者： Bo-Yan Liu He-Ming Yang Yu-Dong Zuo zhi-hao tao Jun-Chun Li Ya-Jing Chang Guo-Qing Tong Yang Jiang School of Materials Science and Engineering Hefei University of TechnologyHefei 230009China State Key Laboratory of Pulsed Power Laser Technology National University of Defense TechnologyHefei 230037China

CsPbBr_(3)inorganic perovskites have been regarded as the promising materials in the field of photo-voltaics because of the high tolerance against *** high energy barrier of phase transition from lead bromide(PbBr_(2))to CsPbBr_(3)perovskite and low solubility of perovskite in organic solvent impede the further improvement of device performance in terms of CsPbBr_(3)solar ***,an intermediate phase-assisted growth of CsPbBr_(3)perovskite was proposed by introducing tetraphenylphosphonium bromide(TPPB)as *** TPPB is expected to react with PbBr_(2)in organic solvent to form an intermediate phase of[***]-PbBr_(2),which not only effectively improves the crystallinity of PbBr2 crystals,but also greatly reduces the phase transition energy barrier,leading to uniform and compact CsPbBr_(3)perovskite films with large grain size and high *** combination with carbon electrode,the CsPbBr_(3)solar cells yield a champion device performance of 9.57%in comparison of pristine CsPbBr_(3)solar cells showing a low efficiency of 8.17%.Furthermore,the intermediate phaseassisted growth of CsPbBr_(3)-based solar cells displays an outstanding storage over720 h.

关键词： CsPbBr_(3) Perovskite solar cells Carbon electrode Hole transport layer free Intermediate phase

Scavenging activity and mechanism study of ferulic acid against reactive carbonyl species acrolein

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2019年第11期20卷 868-876页

作者： zhi-hao tao Chang LI Xiao-fei XU Yuan-jiang PAN Department of Chemistry Zhejiang UniversityHangzhou 310027China College of Life Sciences Zhejiang Chinese Medical UniversityHangzhou 310053China

Acrolein,known as one of the most common reactive carbonyl species,is a toxic small molecule affecting human health in daily *** study is focused on the scavenging abilities and mechanism of ferulic acid and some other phenolic acids against *** the 13 phenolic compounds investigated,ferulic acid was found to have the highest efficiency in scavenging acrolein under physiological *** acid remained at(3.04±1.89)%and acrolein remained at(29.51±4.44)%after being incubated with each other for 24 *** molecular mechanism of the detoxifying process was also *** products,namely 2-methoxy-4-vinyIphenol(product 21)and 5-(4-hydroxy-3-methoxyphenyl)pent-4-enal(product 22),were identified though nuclear magnetic resonanee(NMR)and gas chromatography-mass spectrometry(GC-MS),after the scavenging *** acid showed significant activity in scavenging acrolein under physiological *** study indicates a new method for inhibiting damage from acrolein.

关键词： Acrolein Reactive carbonyl species Ferulic acid Cytotoxicity Oxidative stress

Adaptive subcarrier and bit allocation based on ant colony optimization

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The Journal of China Universities of Posts and Telecommunications 2010年第6期17卷 59-64页

作者： Zhao Ying-hong,XU Xiao-dong,hao zhi-jie,tao Xiao-feng Wireless Technology Innovation Institute,Key Laboratory of Universal Wireless Communication,Ministry of Education,Beijing University of Posts and Telecommunications,Beijing 100876,China Wireless Technology Innovation Institute Key Laboratory of Universal Wireless Communication Ministry of Education Beijing University of Posts and Telecommunications Beijing 100876 China

The problem of resource allocation in multiuser orthogonal frequency division multiplexing （OFDM） system is a combinatorial optimization problem,difficult to obtain optimal solutions in polynomial time. For the sake of reducing complexity,it can be solved either by relaxing constraints and making use of linear algorithms or by metaheuristic methods. In this paper,an algorithm based on ant colony optimization （ACO）,which is a typical algorithm of metaheuristic methods,is proposed for the problem,utilizing excellent search performance of ACO to obtain good solutions. In addition,a parameter is applied to balance the efficiency and fairness of resource allocation. Performance analysis between algorithms based on ACO and genetic algorithm （GA） is carried out,indicating that the proposed algorithm based on ACO outperforms traditional linear algorithms as well as GA in the system throughput with assurance of fairness simultaneously,being as a promising technology for OFDM resource allocation.

关键词： ACO OFDM GA

Numerical analysis of heat transfer enhancement on steam condensation in the presence of air outside the tube

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Nuclear Science and Techniques 2022年第8期33卷 55-68页

作者： Wen-tao Li Xian-Ke Meng hao-zhi Bian Ming Ding Heilongjiang Provincial Key Laboratory of Nuclear Power System and Equipment Harbin Engineering UniversityHarbin 150001China China Nuclear Engineering Consulting Co. Ltd.Beijing 100073China

In loss-of-coolant accidents,a passive containment heat removal system protects the integrity of the containment by condensing *** a large amount of air exists in the containment,the steam condensation heat transfer can be significantly *** on previous research,traditional methods for enhancing pure steam condensation may not be applicable to steam–air *** the present study,new methods of enhancing condensation heat transfer were adopted and several potentially enhanced heat transfer tubes,including corrugated tubes,spiral fin tubes,and ring fin tubes were ***-CCM+was used to determine the effect of enhanced heat transfer tubes on the steam condensation heat *** to the calculations,the gas pressure ranged from 0.2 to 1.6 MPa,and air mass fraction ranged from 0.1 to *** effective perturbation of the high-concentration air layer was identified as the key factor for enhancing steam–air condensation heat ***,the designed corrugated tube performed well at atmospheric pressure,with a maximum enhancement of 27.4%,and performed poorly at high *** the design of spiral fin tubes,special attention should be paid to the locations that may accumulate high-concentration ***,the ring-fin tubes generally displayed good performance under all conditions of interest,with a maximum enhancement of 24.2%.

关键词： Air–steam condensation Numerical simulation Heat transfer enhancement Fin tube

Measurement of boiling heat transfer coefficient in liquid nitrogen bath by inverse heat conduction method

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2009年第5期10卷 691-696页

作者： tao JIN Jian-ping HONG hao ZHENG Ke TANG zhi-hua GAN Institute of Refrigeration and Cryogenics Zhejiang University Hangzhou 310027 China

Inverse heat conduction method (IHCM) is one of the most effective approaches to obtaining the boiling heat transfer coefficient from measured results. This paper focuses on its application in cryogenic boiling heat transfer. Experiments were conducted on the heat transfer of a stainless steel block in a liquid nitrogen bath, with the assumption of a 1D conduction condition to realize fast acquisition of the temperature of the test points inside the block. With the inverse-heat conduction theory and the explicit finite difference model, a solving program was developed to calculate the heat flux and the boiling heat transfer coefficient of a stainless steel block in liquid nitrogen bath based on the temperature acquisition data. Considering the oscillating data and some unsmooth transition points in the inverse-heat-conduction calculation result of the heat-transfer coefficient, a two-step data-fitting procedure was proposed to obtain the expression for the boiling heat transfer coefficients. The coefficient was then verified for accuracy by a comparison between the simulation results using this expression and the verifying experimental results of a stainless steel block. The maximum error with a revised segment fitting is around 6%, which verifies the feasibility of using IHCM to measure the boiling heat transfer coefficient in liquid nitrogen bath.

关键词： Inverse heat conduction method (IHCM) Liquid nitrogen bath Boiling heat transfer coefficient

Aggregation behavior of juvenile Neptunea cumingii and eff ects on seed production

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Journal of Oceanology and Limnology 2020年第5期38卷 1590-1598页

作者： YU Zhenglin HU zhi SONG hao XU tao YANG Meijie ZHOU Cong ZHANG tao CAS Key Laboratory of Marine Ecology and Environmental Sciences Institute of OceanologyChinese Academy of SciencesQingdao 266071China Laboratory for Marine Ecology and Environmental Science Qingdao National Laboratory for Marine Science and TechnologyQingdao 266237China Center for Ocean Mega-Science Chinese Academy of SciencesQingdao 266071China CAS Engineering Laboratory for Marine Ranching Institute of OceanologyChinese Academy of SciencesQingdao 266071China University of Chinese Academy of Sciences Beijing 100049China Shandong Fisheries Technology Extension Center Jinan 250013China

Neptunea cumingii is an important nutrition-rich economic species in *** of *** suff er from high mortality at low temperatures,which has proved a limiting factor in raising seedlings in artifi cial *** research has shown that *** displays aggregation behavior in response to adverse environmental ***,we determined the eff ects of temperature,food,size of juvenile snails,substratum type,and density of juvenile snails on the aggregation behavior of *** show that,at a low(4°C)or a high(22°C)temperature,juvenile snails adjusted to the inhospitable environment by exhibiting increased aggregation ***,their aggregation behaviors diff ered at these two *** was no signifi cant diff erence in the aggregation rate,but the typical aggregation size was larger at 4°C than at 22°*** 10°C or 16°C,aggregation behavior of juvenile snails *** increased in the satiation treatment at 10°C and 16°***-sized juveniles tended to have higher aggregation rates(92.22%)and a larger typical aggregation *** juveniles were distributed in the bottom of shaded substrata.A larger typical aggregation size or higher density signifi cantly reduced the mortality of juvenile snails at a low temperature(4°C).These results broaden our understanding of gastropod aggregation behavior and can be used to develop and improve commercial breeding strategies and resource recovery for ***.

关键词： aggregation behavior Neptunea cumingii environmental temperature survival rate seed production

Borderline Case of Traces and Extensions for Weighted Sobolev Spaces

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Acta Mathematica Sinica,English Series 2023年第9期39卷 1817-1833页

作者： Man Zi Huang Xian tao Wang Zhuang Wang zhi hao Xu MOE-LCSM School of Mathematics and StatisticsHunan Normal UniversityChangsha410081P.R.China

In this paper,we study the traces and the extensions for weighted Sobolev spaces on upper half spaces when the weights reach to the borderline *** first give a full characterization of the existence of trace spaces for these weighted Sobolev spaces,and then study the trace parts and the extension parts between the weighted Sobolev spaces and a new kind of Besov-type spaces(on hyperplanes)which are defined by using integral averages over selected layers of dyadic cubes.

关键词： Sobolev space borderline case trace theorem Besov-type space Muckenhoupt A_p weight

100 cm^(2) Organic Photovoltaic Cells with 23%Efficiency under Indoor Illumination

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Chinese Journal of Polymer Science 2022年第8期40卷 979-988,I0011页

作者： Yong Cui Hui-Feng Yao Ye Xu Peng-Qing Bi Jian-Qi Zhang tao Zhang Ling Hong zhi-hao Chen zhi-Xiang Wei Xiao-tao hao Jian-Hui Hou Laboratory of Polymer Physics and Chemistry Beijing National Laboratory for Molecular SciencesCAS Research/Education Center for Excellence in Molecular SciencesInstitute of ChemistryChinese Academy of SciencesBeijing100190China University of Chinese Academy of Sciences Beijing100049China CAS key laboratory of nanosystem and hierarchical fabrication CAS Center for Excellence in NanoscienceNational Center for Nanoscience and TechnologyBeijing100190China School of Physics State Key Laboratory of Crystal MaterialsShandong UniversityJinan250100China

The application of organic photovoltaic(OPV)cells to drive off-grid microelectronic devices under indoor light has attracted broad *** organic semiconductors intrinsically have less ordered intermolecular packing than inorganic materials,the relatively larger energetic disorder is one of the main results that limit the photovoltaic efficiency of the OPV cells at low carrier ***,we optimize the alkyl chains of non-fullerene acceptors to get suppressed energetic *** find the optimal acceptor DTz-R1 with the shortest alkyl chain has the strongest crystalline property and lowest energetic *** a result,over 26%efficiency is recorded for the 1 cm^(2) OPV cells under a light-emitting diode illumination of 500 *** also fabricate a 100 cm^(2) cell device and get a PCE of 23.0%,which is an outstanding value for large-area OPV *** results suggest that modulation of the energetic disorder is of great importance for further improving the efficiency of OPV cells,especially for indoor applications.

关键词： Organic photovoltaic cells Low light intensity Energetic disorder Energy loss Power conversion efficiency

A Global Optimality Principle for Fully Coupled Mean-field Control Systems

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Acta Mathematicae Applicatae Sinica 2024年第2期40卷 379-413页

作者： tao hao School of Statistics and Mathematics Shandong University of Finance and EconomicsJinan 250014China

This paper concerns a global optimality principle for fully coupled mean-field control *** the first-order and the second-order variational equations are fully coupled mean-field linear FBSDEs. A new linear relation is introduced, with which we successfully decouple the fully coupled first-order variational equations. We give a new second-order expansion of Y^(ε) that can work well in mean-field framework. Based on this result, the stochastic maximum principle is proved. The comparison with the stochastic maximum principle for controlled mean-field stochastic differential equations is supplied.

关键词： optimal control global maximum principle fully coupled general mean-field FBSDE adjoint equation recursive utility