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Bioleaching of vanadium from barren stone coal and its effect on the transition of vanadium speciation and mineral phase

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International Journal of Minerals,Metallurgy and Materials 2018年第3期25卷 253-261页

作者： Xin Wang Hai lin Ying-bo Dong Gan-yu Li School of Civil and Resource Engineering University of Science and Technology Beijing Beijing 100083 China School of Energy and Environmental Engineering University of Science and Technology Beijing Beijing 100083 China Beijing Key Laboratory on Resource-oriented Treatment of Industrial Pollutants Beijing 100083 China

This study determined the optimal conditions required to obtain maximum vanadium extraction and examined the transition of mineral phases and vanadium speciation during the bioleaching process. Parameters including the initial p H value, initial Fe^(2+) concentration, solid load, and inoculum quantity were examined. The results revealed that 48.92 wt% of the vanadium was extracted through bioleaching under optimal conditions. Comparatively, the chemical leaching yield(H_2SO_4, pH 2.0) showed a slower and milder increase in vanadium yield. The vanadium bioleaching yield was 35.11 wt% greater than the chemical leaching yield. The Community Bureau of Reference(BCR) sequential extraction results revealed that 88.62 wt% of vanadium existed in the residual fraction. The bacteria substantially changed the distribution of the vanadium speciation during the leaching process, and the residual fraction decreased to 48.44 wt%. The X-ray diffraction(XRD) and Fourier transform infrared(FTIR) results provided evidence that the crystal lattice structure of muscovite was destroyed by the bacteria.

关键词： bioleaching stone coal BCR-sequential extraction vanadium speciation mineral phase

Leach： an automatic learning cache for inline primary deduplication system

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Frontiers of Computer Science 2014年第2期8卷 175-183页

作者： Bin lin Shanshan LI Xiangke LIAO Jing ZHANG Xiaodong LIU School of Computer National University of Defense Technology Changsha 410073 China

Deduplication technology has been increasingly used to reduce storage costs. Though it has been successfully applied to backup and archival systems, existing techniques can hardly be deployed in primary storage systems due to the associated latency cost of detecting duplicated data, where every unit has to be checked against a substantially large fin- gerprint index before it is written. In this paper we introduce Leach, for inline primary storage, a self-learning in-memory fingerprints cache to reduce the writing cost in deduplica- tion system. Leach is motivated by the characteristics of real- world I/O workloads： highly data skew exist in the access patterns of duplicated data. Leach adopts a splay tree to or- ganize the on-disk fingerprint index, automatically learns the access patterns and maintains hot working sets in cache mem- ory, with a goal to service a majority of duplicated data de- tection. Leveraging the working set property, Leach provides optimization to reduce the cost of splay operations on the fin- gerprint index and cache updates. In comprehensive experi- ments on several real-world datasets, Leach outperforms con- ventional LRU （least recently used） cache policy by reducing the number of cache misses, and significantly improves write performance without great impact to cache hits.

关键词： deduplication duplicate detection splay tree,cache

Aerodynamic Design Methodology for Blended Wing Body Transport

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Chinese Journal of Aeronautics 2012年第4期25卷 508-516页

作者： LI Peifeng ZHANG Binqian CHEN Yingchun YUAN Changsheng lin Yu College of Aeronautics Northwestern Polytechnical University Xi 'an 710072 China Shanghai Aircraft Design and Research lnstitute Commercial Aircraft Corporation of China Ltd. Shanghai200232 China

This paper puts forward a design idea for blended wing body（BWB）.The idea is described as that cruise point,maximum lift to drag point and pitch trim point are in the same flight *** to this design idea,design objectives and constraints are *** applying low and high fidelity aerodynamic analysis tools,BWB aerodynamic design methodology is established by the combination of optimization design and inverse design *** lift to drag ratio,pitch trim and acceptable buffet margin can be achieved by this design *** 300-passenger BWB configuration based on static stability design,as compared with initial configuration,the maximum lift to drag ratio and pitch trim are achieved at cruise condition,zero lift pitching moment is positive,and buffet characteristics is *** burn of 300-passenger BWB configuration is also significantly reduced as compared with conventional civil *** aerodynamic design is carried out under the constraints of BWB design requirements,the design configuration fulfills the demands for interior layout and provides a solid foundation for continuous work.

关键词： blended wing body aerodynamic configurations computational fluid dynamics optimization design inverse design

SCStore： Managing Scientific Computing Packages for Hybrid System with Containers

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Tsinghua Science and Technology 2017年第6期22卷 675-681页

作者： Wusheng Zhang Jiao lin Weiping Xu Haohuan Fu Guangwen Yang Department of Computer Science and Technology Tsinghua University Beijing 100084 China National Supercomputing Center in Wuxi Wuxi 210008 China Department of Computer Science and Technology Tsinghua University Beijing 100084 China. Department of Earth System Science Tsinghua University Beijing 100084 China

Managing software packages in a scientific computing environment is a challenging task, especially in the case of heterogeneous systems. It is error prone when installing and updating software packages in a sophisticated computing environment. Testing and performance evaluation in an on-the-fly manner is also a troublesome task for a production system. In this paper, we discuss a package management scheme based on containers. The newly developed method can ease the maintenance complexity and reduce human mistakes. We can benefit from the self-containing and isolation features of container technologies for maintaining the software packages among intricately connected clusters. By deploying the Super Computing application Strore（SCStore） over the WAN connected world-largest clusters, it proved that it can greatly reduce the effort for maintaining the consistency of software environment and bring benefit to achieve automation.

关键词： high performance computing package management container hybrid system

Study on the hot deformation behavior of Al-Zn-Mg-Cu-Cr aluminum alloy during multi-stage hot compression

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Acta Metallurgica Sinica(English Letters) 2009年第2期22卷 110-116页

作者： Gaoyong lin Xiaoyan ZHENG Wei YANG Di FENG Dashu PENG School of Materials Science and Engineering Central South UniverSity Changsha 410083 China

The mechanical behavior and microstructures of an Al-Zn-Mg-Cu-Cr aluminum alloy during multi-stage hot deformation were investigated by thermal stimulation test, optical microscopy, and transmission electron microscopy. The true stress vs true strain curves and the microstructure evolution of two hot deformation procedures were gained. The flow stress of the alloy studied decreases with increasing the deforming passes and declining the temperature, and the larger the temperature decline between adjacent stages, the larger the peak stress fall is. The stress-strain behavior mainly result from the dynamic recovery during deformation, the static recovery and recrystallization in the delay time, and the second phases precipitated from the matrix at high temperature.

关键词： Al-Zn-Mg-Cu-Cr alloy Multi-stage compression Flow stress and peak stress Micro-structure evolution

Bio-remediation of acephate–Pb(Ⅱ) compound contaminants by Bacillus subtilis FZUL-33

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Journal of Environmental Sciences 2016年第7期28卷 94-99页

作者： Wenting lin Zhen Huang Xuezhen Li Minghua Liu Yangjian Cheng The College of Environment and Resources Fuzhou University

Removal of Pb^（2＋）and biodegradation of organophosphorus have been both widely investigated respectively. However, bio-remediation of both Pb^（2＋）and organophosphorus still remains largely unexplored. Bacillus subtilis FZUL-33, which was isolated from the sediment of a lake, possesses the capability for both biomineralization of Pb^（2＋）and biodegradation of acephate. In the present study, both Pb^（2＋）and acephate were simultaneously removed via biodegradation and biomineralization in aqueous *** experiments were conducted to study the influence of p H, interaction time and Pb^（2＋）concentration on the process of removal of Pb2＋. At the temperature of 25°C, the maximum removal of Pb^（2＋）by B. subtilis FZUL-33 was 381.31 ± 11.46 mg/g under the conditions of p H 5.5, initial Pb^（2＋）concentration of 1300 mg/L, and contact time of 10 min. Batch experiments were conducted to study the influence of acephate on removal of Pb^（2＋）and the influence of Pb2＋on biodegradation of acephate by B. subtilis FZUL-33. In the mixed system of acephate–Pb2＋, the results show that biodegradation of acephate by B. subtilis FZUL-33 released PO43＋, which promotes mineralization of Pb2＋. The process of biodegradation of acephate was affected slightly when the concentration of Pb2＋was below 100 mg/L. Based on the results, it can be inferred that the B. subtilis FZUL-33 plays a significant role in bio-remediation of organophosphorus-heavy metal compound contamination.

关键词： Acephate–Pb2+ Bacillus subtilis Biodegradation Biomineralization

Investigation on Uniaxial Tensile Instability of USIBOR1500 Steel Sheets at Elevated Temperature

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Chinese Journal of Mechanical Engineering 2010年第1期23卷 94-99页

作者： MIN Junying lin Jianping TIAN Haobin SUN Guohua XU Zhou College of Mechanical Engineering Tongii University Shanghai 201804 China College of Mechanical and Electrical Engineering Shanghai Second Polytechnic University Shanghai 201209 China

In the sheet forming process with stretch, diffuse instability and localized instability usually occur in the process one after another. The necking rate has a great impact on the instability process and the forming limits of the rate sensitive material, such as USIBOR1500 steel sheets at elevated temperature. The available reports about this steel mainly focus on hot uniaxial tensile, martensitic transformation and forming process, but there are few investigations on instability behavior and forming limits. Based on Inoue Kachiro＇s flow stress constitutive model at elevated temperature, combined with Swift＇s diffuse instability rule and Hill＇s localized instability nile, the relation is theoretically deduced between the diffuse necking rate along with the localized necking rate and the exponent of strain rate sensitivity together with the strain rate in the case of the USIBOR1500 steel sheets at elevated temperature. According to the time-temperature characteristics of the hot stamping process, tensile tests of the steel sheets were carried out on Gleeble3800, and the stress-strain curves were obtained at different temperatures and different strain rates. Then the values of the exponent of strain rate sensitivity and the hardening exponent were obtained through fitting the curves by least squares. The tests also helped to provide the distribution laws of the major strain of the specimens and the uniform strains as well as the necking width. The uniform strains obtained from the tests are matched well with the theoretical calculations.

关键词： USIBOR1500 uniaxial tensile instability uniform strain necking rate

Pollutants identification of ambient aerosols by two types of aerosol mass spectrometers over southeast coastal area, China

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Journal of Environmental Sciences 2018年第2期30卷 252-263页

作者： Jinpei Yan Liqi Chen Qi lin Shuhui Zhao Lei Li Key Laboratory of Global Change and Marine-Atmospheric Chemistry Third Institute of Oceanography SOA Xiamen 361005 China Institute of Atmospheric Environment Safety and Pollution Control Jinan University Ouangzhou 510632 China

Two different aerosol mass spectrometers, Aerodyne Aerosol Mass Spectrometer（AMS） and Single Particle Aerosol Mass Spectrometer（SPAMS） were deployed to identify the aerosol pollutants over Xiamen, representing the coastal urban area. Five obvious processes were classified during the whole observation period. Organics and sulfate were the dominant components in ambient aerosols over Xiamen. Most of the particles were in the size range of 0.2–1.0 μm, accounting for over 97% of the total particles measured by both ***, as well as sulfate, measured by AMS were in good correlation with measured by SPAMS. However, high concentration of NH4＋was obtained by AMS, while extremely low value of NH4＋was detected by SPAMS. Contrarily, high particle number counts of NO3-and Clwere given by SPAMS while low concentrations of NO3-and Cl-were measured by AMS. The variations of POA and SOA obtained from SPAMS during event 1 and event 2 were in accordance with the analysis of HOA and OOA given by AMS, suggesting that both of AMS and SPAMS can well identify the organic clusters of aerosol particles. Overestimate or underestimate of the aerosol sources and acidity would be present in some circumstances when the measurement results were used to analyze the aerosol properties, because of the detection loss of some species for both instruments.

关键词： Aerosol Size distribution Chemical composition Aerosol mass spectrometer Aerosol source

Systemic management for patients with hepatobiliary tumors in a multi-dimensional view

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Hepatobiliary Surgery and Nutrition 2019年第6期8卷 626-628页

作者： Jianzhen lin Haitao Zhao Department of Liver Surgery Chinese Academy of Medical Sciences and Peking Union Medical College(CAMS&PUMC)Peking Union Medical College HospitalBeijing 100730China

As one of the most leading causes of cancer-related mortality,hepatobiliary tumors(HBT)are featured as limited treatment and poor *** to the complexity and heterogeneity of epidemiologic risk factors,clinicopathological characteristics and cancer genomics,it is still hard to form a normalized clinical management for patients with advanced *** a long period of time,surgery-oriented comprehensive treatment is the mainstream medical care for clinical treatment for HBT,which emphasizes to categorize HBT into resectable/transplantable stage or unresectable/untransplantable stage.

关键词： hepato patients clinical