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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2011年第6期12卷 461-469页

作者： Dan-qing YU Yue LIU Zhong-biao wu Department of Environmental Engineering Zhejiang University Hangzhou 310027 China Zhejiang Provincial Engineering Research Center of Industrial Boiler & furnace flue Gas Pollution Control Hangzhou 310027 China

Six transition metal oxides were added in ceria-modified titania using a sol-gel method for catalytic oxidation of *** MnOx based catalyst was found to be the most active one,with which toluene could be decomposed completely at 200 *** greatest Mn/Ti and molar ratio of the mobile oxygen to the total oxygen concentration,together with a large surface area and a low reduction peak-starting temperature,would result in its best activity in toluene oxidation.

关键词： Transition metal oxides CeO2/TiO2 Sol-gel method Catalytic oxidation Toluene

Self-consistent extraction of photoabsorption time delays in attosecond streak camera

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Science China(Physics,Mechanics & Astronomy) 2024年第12期67卷 8-16页

作者： Yutong Gao Hongcheng Ni Andreas Becker Jian wu State Key Laboratory of Precision Spectroscopy East China Normal UniversityShanghai 200241China Collaborative Innovation Center of Extreme Optics Shanxi UniversityTaiyuan 030006China JILA and Department of Physics University of ColoradoBoulder 80309-0440USA Chongqing Key Laboratoryof PrecisionOptics Chongqing Institute of East China Normal UniversityChongqing 4112China

Photoionization can generally be decomposed into a photoabsorption process plus a half-scattering *** streaking time delay observed in the attosecond streak camera,correspondingly,can be decomposed into a photoabsorption time delay and a continuum time *** propose a self-consistent method to account for the potential-laser coupling effect and extract the intrinsic absorption time delay,without invoking an implicit assumption of a constant continuum correction made in previous streaking *** concept is based on an iterative technique starting from an initial guess of the absorption time delay and using classical electron trajectories to consistently remove the coupling-induced momentum shift to the streak *** show that the self-consistent iterative algorithm converges quickly and is robust against different initial *** method is applied to laser-induced ionization of atoms to obtain the absorption time delay in resonant two-photon ionization and to explore possible time delays in above-threshold *** results confirm an absorption time delay linearly dependent on the ionizing pulse duration in resonant two-photon *** method is also shown to perform better than conventional methods and to identify a small negative absorption time delay(less than 2 attoseconds) in above-threshold ionization.

关键词： attosecond streak camera photoabsorption time delay photoionization

Succession of bacterial community along with the removal of heavy crude oil pollutants by multiple biostimulation treatments in the Yellow River Delta,China

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Journal of Environmental Sciences 2011年第9期23卷 1533-1543页

作者： Sulin Yu Shuguang Li Yueqin Tang Xiaolei wu Department of Energy and Resources Engineering College of Engineering Peking University Beijing 100871 China

Multiple biostimulation treatments were applied to enhance the removal of heavy crude oil pollutants in the saline soil of Yellow River *** of the soil bacterial community were monitored using the terminal restriction fragment length polymorphism （T-RfLP） and clone library *** 140-day microcosm experiments showed that low C：N：P ratio,high availability of surfactant and addition of bulking agent significantly enhanced the performance,leading to the highest total petroleum hydrocarbon ***,the bacterial community was remarkably changed by the multiple biostimulation treatments,with the Deltaproteobacteria,firmicutes,Actinobacteria,Acidobacteria and Planctomycetes being inhibited and the Alphaand Beta-proteobacteria and some unknown Gammaproteobacteria bacteria being *** addition,different hydrocarbon-degraders came to power in the following *** the first stage,the Alcanivorax-related Gammaproteobacteria bacteria dominated in the biostimulated soil and contributed mainly to the biodegradation of easily degradable portion of the heavy crude *** the bacteria belonging to Alphaproteobacteria,followed by bacteria belonging to Candidate division OD1,became the dominant oil-degraders to degrade the remaining recalcitrant constituents of the heavy crude oil.

关键词： heavy crude oil contamination biostimulation bacterial community T-RfLP Yellow River Delta saline soil

Numerical simulations of sloshing and suppressing sloshing using the optimization technology method

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Applied Mathematics and Mechanics(English Edition) 2018年第6期39卷 845-854页

作者： Hui GUAN Yifei XUE Zhiiun WEI Chuijie wu College of Meteorology and Oceanography National University of Defense Technology Nanjing 211101 China School of Aerospace Engineering Tsinghua University Beijing 100084 China State Key Laboratory of Structural Analysis for Industrial Equipment School of Aeronautics and Astronautics Dalian University of Technology Dalian 116024 Liaoning Province China School of Aeronautics and Astronautics Dalian University of Technology Dalian 116024 Liaoning Province China

Sloshing is a common phenomenon in nature and industry, and it is important in many fields, such as marine engineering and aerospace engineering. To reduce the sloshing load on the side walls, the topology optimization and optimal control methods are used to design the shape of the board, which is fixed in the middle of the tank. The results show that the new board shape, which is designed via topology optimization, can significantly reduce the sloshing load on the side wall.

关键词： sloshing volume of fluid (VOf) method suppressing sloshing topologyoptimization

Integration strategies of hydrogen network in a refinery based on operational optimization of hydrotreating units

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Chinese Journal of Chemical Engineering 2017年第8期25卷 1061-1068页

作者： Le wu Xiaoqiang Liang Lixia Kang Yongzhong Liu Department of Chemical Engineering Xi'an Jiaotong University Key Laboratory of Thermo-fluid Science and Engineering Ministry of Education

Inferior crude oil and fuel oil upgrading lead to escalating increase of hydrogen consumption in *** is imperative to reduce the hydrogen consumption for energy-saving operations of *** integration strategy of hydrogen network and an operational optimization model of hydrotreating(HDT)units are proposed based on the characteristics of reaction kinetics of HDT *** solving the proposed model,the operating conditions of HDT units are optimized,and the parameters of hydrogen sinks are determined by coupling hydrodesulfurization(HDS),hydrodenitrification(HDN)and aromatic hydrogenation(HDA)*** example case of a refinery with annual processing capacity of eight million tons is adopted to demonstrate the feasibility of the proposed optimization strategies and the *** show that HDS,HDN and HDA reactions are the major source of hydrogen consumption in the *** total hydrogen consumption can be reduced by 18.9%by applying conventional hydrogen network optimization *** the hydrogen network is optimized after the operational optimization of HDT units is performed,the hydrogen consumption is reduced by28.2%.When the benefit of the fuel gas recovery is further considered,the total annual cost of hydrogen network can be reduced by 3.21×10~7CNY·a^(-1),decreased by 11.9%.Therefore,the operational optimization of the HDT units in refineries should be imposed to determine the parameters of hydrogen sinks base on the characteristics of reaction kinetics of the hydrogenation processes before the optimization of the hydrogen network is performed through the source-sink matching methods.

关键词： Hydrogenation reaction kinetics Hydrogen network Integration strategies Optimization

Numerical analysis of the interaction of 3D compressible bubble clusters

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Applied Mathematics and Mechanics(English Edition) 2019年第8期40卷 1181-1196页

作者： Hui GUAN Jincheng WANG Zhijun WEI Chuijie wu College of Meteorology and Oceanography National University of Defense TechnologyNanjing 211101China School of Aeronautics and Astronautics Dalian University of TechnologyDalian 116024Liaoning ProvinceChina State Key Laboratory of Coastal and Offshore Engineering Dalian University of TechnologyDalian 116024Liaoning ProvinceChina

Based on the bubble dynamic theory and the compressible two-phase flow solver of the open source software OpenfOAM, a numerical simulation study is carried out on the interactions of bubble clusters in a closed volume. The bubble dynamics and interactions of a single bubble, two bubbles, and four bubbles are investigated under the working conditions without and with the presence of a free surface. Through a parametric study, the qualitative patterns of the variations of the bubble collapse period, the volume compressibility, the bubble pressure peak value, and the breakdown, fusion, and separation phenomena with the parameters such as the bubble pressure, the radius size, the bubble spacing, and the distance from the free surface are obtained. The main factors affecting the bubble morphology and the dynamic characteristics are summarized from numerous parameter experiments. It is shown that, in the absence of a free surface, the main factors are the relative size of the bubbles, the pressure of the liquid, and the pressure differences among the bubbles, while in the presence of a free surface, the main factor is the pressure of the liquid between the upper surface of the bubble and the free surface.

关键词： compressible two-phase flow interaction of bubbles OpenfOAM

INfLUENCE Of SO_4^(2-) AND Cl-ON THE CORROSION BEHAVIOR Of COPPER TUBE IN AIR-CONDITIONING SYSTEM

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Acta Metallurgica Sinica(English Letters) 2004年第1期17卷 92-96页

作者： C.S.wu Z.Zhang f.H.Cao J.Q.Zhang J.M.Wang C.N.Cao Department of Chemistry Yuquan CampusZhejiang University Hangzhou 310027ChinaDepartment of Chemistry Yuquan CampusZhejiang University Hangzhou 310027ChinaDepartment of Chemistry Yuquan CampusZhejiang University Hangzhou 310027ChinaDepartment of Chemistry Yuquan CampusZhejiang University Hangzhou 310027China State Key Laboratory for Corrosion and Protection of Metals Shenyang 110016 ChinaDepartment of ChemistryYuquan Campus Zhejiang University Hangzhou 310027ChinaDepartment of ChemistryYuquan Campus Zhejiang University Hangzhou 310027China State Key Laboratory for Corrosion and Protection of MetalsShenyang 110016 China

The influence of chloride or sulphur dioxide on the corrosion behavior of copper tube in the air-conditioning system was studied using scanning electron microscope (SEM), energy dispersion spectrometer (EDS) and cyclic polarization techniques. The results showed that the corrosion of copper tube are mainly caused by the SO42- and Cl- ions in the circulating water, and the former is mainly responsible for the general corrosion of the copper tube whilst the latter for the pitting corrosion. The different influences of SG42- and Cl- ions on the corrosion type of copper tube may be attributed to that the radius of SO42- ion is much larger than that of Cl- ion. Meanwhile the results also indicated that SO42- inhibits the pitting corrosion caused by Cl- and Cl- inhibits the general corrosion initiated by SO42- due to their competitive adsorption on the copper matrix.

关键词： copper corrosion behavior influence SO42- ion Cl- ion

Reliability and Validity of Addiction Severity Index in Drug Users with Methadone Maintenance Treatment in Guizhou Province, China

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Biomedical and Environmental Sciences 2008年第4期21卷 308-313页

作者： TAO LIANG EN-wu LIU HUA ZHONG BING WANG LI-MEI SHEN ZHENG-LAI wu School of Nursing Peking Union Medical College Chinese Academy of Medical Sciences Beijing 100730 China Chinese Center for Disease Control and Prevention Beijing 100050 China Guizhou Provincial Center for Disease Control and Prevention Guiyang 550003 Guizhou China Department of Epidemiology Peking Union Medical College Beijing 100005 China

Objective To evaluate the reliability and validity of the Chinese version of addiction severity index （ASI）-5th version （ASI-C-5）, in illegal drug users receiving methadone maintenance treatment （MMT） in China. Methods One hundred and eighty-six heroin addicts （144 men and 42 women） receivihg MMT at three clinics in Guizhou province, southwest China, were recmited. They were all interviewed with a questionnaire of ASI-C-5 and 35 were re-interviewed at an interval of seven days to assess its test-retest reliability. Results Cronbach＇s alpha for internal consistency of CSs varied from 0.60 to 0.81 in all domains. Test-retest reliability of composite scores （CSs） of ASI-C-5 were satisfactory （r=0.38-0.97）. Based on item analysis and expert＇s suggestions, five items were deleted and one item was modified in ASI-C-5. Criterion validity of ASI-C-5 was found acceptable, as compared to addicts＇ self-rating anxiety scale （SAS） and self-rating depression scale （SDS）（r=0.59 and 0.45） except for social support rating scale （SSRS）. Conclusions ASI-C-5 can be used for heroin addicts receiving MMT with acceptable reliability and validity.

关键词： Drug dependence Addiction severity index Reliability Validity Methadone maintenance treatment

Correction of TOPEX altimeter data error and its preliminary results in application

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Chinese Science Bulletin 1997年第17期42卷 1451-1455页

作者： Zheng, DW wu, HQ Shanghai Observatory Chinese Academy of Sciences Shanghai China

TOPEX/POSEIDON is an altimetric satellite mission jointly conducted by NASA, the US

关键词： ocean satellite altimeter instrument drift correction sea-level change.

Prefetch-aware fingerprint cache management for data deduplication systems

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frontiers of Computer Science 2019年第3期13卷 500-515页

作者： Mei LI Hongjun ZHANG Yanjun wu Chen ZHAO Institute of Software Chinese Academy of Sciences Beijing 100190 China University of Chinese Academy of Sciences Beijing 100049 China

Data deduplication has been widely utilized in large-scale storage systems, particularly backup systems. Data deduplication systems typically divide data streams into chunks and identify redundant chunks by comparing chunk fingerprints. Maintaining all fingerprints in memory is not cost-effective because fingerprint indexes are typically very large. Many data deduplication systems maintain a fingerprint cache in memory and exploit fingerprint prefetching to accelerate the deduplication process. Although fingerprint prefetching can improve the performance of data deduplication systems by leveraging the locality of workloads, inaccurately prefetched fingerprints may pollute the cache by evicting useful fingerprints. We observed that most of the prefetched fingerprints in a wide variety of applications are never used or used only once, which severely limits the performance of data deduplication systems. We introduce a prefetch-aware fingerprint cache management scheme for data deduplication systems (PreCache) to alleviate prefetch-related cache pollution. We propose three prefetch-aware fingerprint cache replacement policies (PreCache-UNU, PreCache-UOO, and PreCache-MIX) to handle different types of cache pollution. Additionally, we propose an adaptive policy selector to select suitable policies for prefetch requests. We implement PreCache on two representative data deduplication systems (Block Locality Caching and SiLo) and evaluate its performance utilizing three real-world workloads (Kernel, MacOS, and Homes). The experimental results reveal that PreCache improves deduplication throughput by up to 32.22% based on a reduction of on-disk fingerprint index lookups and improvement of the deduplication ratio by mitigating prefetch-related fingerprint cache pollution.

关键词： data deduplication fingerprint prefetch fingerprint cache