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Rare Metals 2022年第10期41卷 3475-3485页

作者： Xiao-Min Wu Fei Xie yong-Lin Yao Yue Sun Zhong-Sheng Hua Zhuo zhao yong-xiang Yang Anhui Province Key Laboratory of Metallurgical Engineering&Resources Recycling School of Metallurgical EngineeringAnhui University of TechnologyMaanshan243002China Department of Materials Science and Engineering Delft University of TechnologyDelft2628CDNetherlands

In order to take full advantage of the secondary resources,in this paper,we reported a template-free process to prepare porous Co microfibers from spent lithiumion batteries(LIBs).First,the waste LiCoO_(2) powders were leached by oxalic acid at a suitable temperature,and rodlike cobalt oxalate powders were ***,the porous Co microfibers were prepared by using the cobalt oxalate as precursors through a thermal decomposition at420 ℃ under nitrogen *** prepared Co microfibers possess diameters of 1-2 μm,and each microfiber consists of small particles with size of100-200 *** Co microfibers(25 wt%)/paraffin composite exhibited excellent microwave absorption *** the sample thickness is 4.5 mm,the reflection losses reach-36.14 and-38.20 dB at 4.16 and 17.60 GHz,respectively,and the effective bandwidth reaches up to 5.52 *** indicates that the Co microfibers can be used as a promising microwave ***,this paper demonstrates a novel process to make a high value-added product through recycling from the spent lithium-ion *** addition,it is advantageous to eliminate the hazard of spent lithium-ion batteries and electromagnetic radiation to environment and human health.

关键词： Spent lithium-ion batteries(LIBs) Co microfibers Recycling Oxalic acid leaching Microwave absorption

Computer generation of detailed reaction networks in hydrocracking of Fischer-Tropsch wax

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Chinese Journal of Chemical Engineering 2022年第1期35卷 342-349页

作者： Jingjing Wang Wei zhao Kunpeng Song Hongwei xiang Liping Zhou yong Yang yongwang Li State Key Laboratory of Coal Conversion Institute of Coal ChemistryChinese Academy of SciencesTaiyuan 030001China National Energy Center for Coal to Liquids Synfuels China Co.Ltd.Huairou DistrictBeijing 101400China University of Chinese Academy of Sciences Beijing 100049China

Fischer-Tropsch synthesis(FTS)wax is a mixture of linear hydrocarbons with carbon number from C7 to C70+.Converting FTS wax into high-quality diesel(no sulfur and nitrogen contents)by hydrocracking technology is attractive in economy and *** study of the hydrocracking of FTS wax in elementary step level is very challenging because of the huge amounts of reactions and species *** of reaction networks for hydrocracking of FTS wax in which the chain length goes up to C70 is described on the basis of Boolean adjacency *** of the species(including paraffins,olefins and carbenium ions)involved in the elementary steps is represented digitally by using a(N+3)N matrix,in which a group of standardized numbering rules are designed to guarantee the unique identity of the ***,the elementary steps are expressed by computer-aided matrix transformations in terms of proposed reaction *** memory allocation is used in species storage and a characteristic vector with nine elements is designed to store the key information of a(N+3)N matrix,which obviously reduces computer memory consumption and improves computing *** detailed reaction networks of FTS wax hydrocracking can be generated smoothly and accurately by the current *** work is the basis of advanced elementary-step-level kinetic modeling.

关键词： Hydrocracking Fischer-Tropsch synthesis wax Boolean adjacency matrixes Reaction network

Exploring the influence of environmental factors in partitioning evapotranspiration along an elevation gradient on Mount Gongga, eastern edge of the Qinghai-Tibet Platea, China

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Journal of Mountain Science 2020年第2期17卷 384-396页

作者： SUN Ju-ying SUN xiang-yang HU zhao-yong WANG Gen-xu Institute of Mountain Hazards and Environment Chinese Academy of SciencesChengdu 610041China University of Chinese Academy of Sciences Beijing 100049China

Evapotranspiration(ET) is a crucial part of the global hydrological cycle, and quantifying ET components is significant for understanding the global water cycle and energy balance. However, there is no consensus on the value of ET components, especially in topographic abrupt change zone, such as eastern margin of the Qinghai-Tibet Platea, where values of ET changes along the altitudinal gradients. Our aim is to explore the influencing factors in partitioning evapotranspiration and how ET components change with increasing elevations. A novel approach was proposed to estimate ET components by adding net solar radiation(Rn) instead of the vapor pressure deficit(VPD) into the underlying water use efficiency(u WUE) model based on one-year continuous measurements of flux data along the elevation gradient on Mount Gongga. Correlation analysis shows that the u WUE model's performance can be improved significantly by considering Rn instead of VPD, with correlation coefficients increasing by 35%-64%. The ratios of transpiration(T) to ET(T/ET) were 0.47, 0.48, 0.50 and 0.35 for the deciduous broadleaf forest(BF), mixed coniferous and deciduous broadleaf forest(MF), evergreen needle forest(ENF) and shrub land(SL), respectively. Leaf area index(LAI) and air temperature(Ta) were the two main controlling factors in determining T/ET during the growing season and at an annual scale, while Rn and Ta played more important roles during the dormant season. This study highlights the importance of incorporating Rn in partitioning evapotranspiration by using the water use efficiency(WUE) method in a humid mountainous region, which can improve the estimation of T/ET on a global scale.

关键词： Eddy covariance Water use efficiency Radiation Evapotranspiration components

Oscillatory Periodic Solutions of Nonlinear Second Order Ordinary Differential Equations

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Acta Mathematica Sinica,English Series 2005年第3期21卷 491-496页

作者： yong xiang LI Department of Mathematics Northwest Normal University Lanzhou 730070 P. R. China

In this paper the existence results of oscillatory periodic solutions are obtained for a second order ordinary differential equation -u″（t） = f（t, u（t））, where f ： R^2 → R is a continuous odd function and is ... 详细信息

关键词： Second order differential equation Oscillatory periodic solution Cone Fixed point index

iTRAQ-based quantitative proteome characterization of wheat grains during filling stages

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Journal of Integrative Agriculture 2017年第10期16卷 2156-2167页

作者： CUI yong YANG Ming-ming DONG Jian zhao Wan-chun GAO xiang College of Agronomy Northwest A&F University Yangling 712100 P.R.China Wheat Engineering Research Center of Shaanxi Province Yangling 712100 P.R. China

Using isobaric tags for relative and absolute quantification （iTRAQ） and associated analytic technologies, we have cataloged and compared 7 069 unique wheat proteins expressed during four substages of the filling stage. Among them, 859 are differentially expressed, showing at least a 2-fold difference in concentration across substages. Differentially expressed proteins （DEPs） includind high-molecular weight giutenin subunit （W5AIU1）, low-molecular weight glutenin subunit （QSW3V4）, gliadin/avenin-like seed protein （D2KFG9）, and avenin-like protein （W5DVL2）, all of which have previously been identified as important for nutritional quality and bread-making properties, and all of which were found to increase at the latter stages of development. We have applied statistical techniques to group the proteins into hierarchical clusters, and have consulted databases to infer functional and other relationships among the identified proteins.

关键词： wheat proteome isobaric tags for relative and absolute quantification (iTRAQ) grain filling

Scheduling piece requests blindly and randomly for peer-to-peer live streaming

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The Journal of China Universities of Posts and Telecommunications 2010年第2期17卷 76-84页

作者： CHEN Yi-shuai CHEN Chang-jia zhao yong-xiang LI Chun-xi School of Electrical and Information Engineering Beijing Jiaotong University Beijing 100044 China

The design of piece scheduling algorithm is fundamental in mesh-based peer-to-peer （P2P） live streaming systems. This article regards the piece propagation process in P2P live streaming system as a conflict process, where peers compete to get the piece as soon as possible to meet the tight timing requirement of the live system. In this vision, the authors reduce the piece scheduling problem as a conflict resolution problem, and propose a blind random scheduling method to resolve it. The algorithm can be described as： 1） pieces are scheduled independently; 2） conflicts are resolved by the random back off algorithm. The theoretical analysis and simulation results prove that the algorithm scales well with the network size, and can obtain near-optimal in-time delivery of pieces. The algorithm is also easy to implement in the real-world system.

关键词： peer-to-peer live streaming conflict resolution exponential back off piece scheduling

Three-dimensional hydrodynamic and water quality model for TMDL development of Lake Fuxian,China

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Journal of Environmental Sciences 2012年第8期24卷 1355-1363页

作者： Lei zhao Xiaoling Zhang yong Liu Bin He xiang Zhu Rui Zou Yuanguan Zhu Research Center for Eco-Environmental Sciences Chinese Academy of SciencesBeijing 100085China College of Environmental Science and Engineering Key Laboratory of Water and Sediment Sciences(MOE)Peking UniversityBeijing 100871China Tetra Tech Inc.10306 Eaton PlaceSte 340FairfaxVA 22030USA Institute for Environmental Sciences Kunming 650034China

Lake Fuxian is the largest deep freshwater lake in China. Although its average water quality meets Class I of the China National Water Quality Standard （CNWQS）, i.e., GB3838-2002, monitoring data indicate that the water quality approaches the Class II threshold in some areas. Thus it is urgent to reduce the watershed load through the total maximum daily load （TMDL） program. A three-dimensional hydrodynamic and water quality model was developed for Lake Fuxian, simulating flow circulation and pollutant fate and transport. The model development process consists of several steps, including grid generation, initial and boundary condition configurations, and model calibration processes. The model accurately reproduced the observed water surface elevation, spatiotemporal variations in temperature, and total nitrogen （TN）, total phosphorus （TP）, and chemical oxygen demand （COD） concentrations, suggesting a reasonable numerical representation of the prototype system for further TMDL analyses. The TMDL was calculated using two interpretations of the water quality standards for Class I of the CNWQS based on the maximum instantaneous surface and annual average surface water concentrations. Analysis of the first scenario indicated that the TN, TP and COD loads should be reduced by 66%, 68% and 57%, respectively. Water quality was the highest priority; however, local economic development and cost feasibility for load reduction can pose significant issues. In the second interpretation, the model results showed that, under the existing conditions, the average water quality meets the Class I standard and therefore load reduction is unnecessary. Future studies are needed to conduct risk and cost assessments for realistic decision-making.

关键词： hydrodynamic and water quality model Lake Fuxian water quality prediction total maximum daily load

Cloud download system optimizing by job and notification scheduling

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The Journal of China Universities of Posts and Telecommunications 2014年第4期21卷 47-53,63页

作者： XU Ying-ying CHEN Chang-jia zhao yong-xiang CHEN Yi-shuai School of Electronics and Information Engineering Beijing Jiaotong University

With expansion of cloud-based applications, it is necessarily for business service provider to deal with how to provision resources to server customers. In cloud download, the service provider faces great challenge on determining when to process job and when to notify the user to meet the conflicting objectives, i.e., the service profit maximization and user satisfaction maximization. An economic model was proposed to find job and notification scheduling strategies for making tradeoffs between user satisfaction and profit of the system, in this model, optimization problems are formulated as follows, profit maximization under a satisfaction target and then satisfaction optimization with a profit bound. By solving these optimization problems, the optimal scheduling strategies are obtained under various quality requirements of service. It is demonstrated that the proposed strategy can obtain better performance than the system without the intelligent scheduling strategy.

关键词： cloud download economic model optimization scheduling strategy user satisfaction

Characterization of Ppd-D1 alleles on the developmental traits and rhythmic expression of photoperiod genes in common wheat

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Journal of Integrative Agriculture 2016年第3期15卷 502-511页

作者： zhao yong-ying WANG xiang WEI Li WANG Jing-xuan YIN Jun National Engineering Research Center for Wheat Collaborative Innovation Center of Henan Grain CropsState Key Laboratory of Wheat and Maize Crop ScienceCollege of AgricultureHenan Agricultural UniversityZhengzhou 450002P.R.China National Laboratory of Wheat Engineering Key Laboratory of Wheat Biology and Genetic Breeding in Central Huang-Huai RegionMinistry of AgriculturalKey Laboratory of Wheat Biology of Henan ProvinceWheat Research InstitutionHenan Academy of Agricultural SciencesZhengzhou 450002P.R.China

Photoperiodic response is an important characteristic that plays an important role in plant adaptability for various environments. Wheat cultivars grow widely and have high yield potential for the strong photoperiod adaptibility. To assess the photoperiodic response of different genotypes in wheat cultivars, the photoperiodic effects of the Ppd-D1 alleles and the expressions of the related TaGI, TaCO and Ta FT genes in Liaochun 10 and Ningchun 36 were investigated under the short-day（6 h light, SD）, moderate-day（12 h light, MD） and long-day（24 h light, LD） conditions. Amplicon length comparison indicated that the promoter of Ppd-D1 in Ningchun 36 is intact, while Liaochun 10 presented the partial sequence deletion of Ppd-D1 promoter. The durations of all developmental stages of the two cultivars were reduced by subjection to an extended photoperiod, except for the stamen and pistil differentiation stage in the Liaochun 10 cultivar. The expression levels of the Ppd-D1 alleles and the TaGI, TaCO and TaFT genes associated with the photoperiod pathway were examined over a 24-h period under SD and MD conditions. The relationships of different photoperiodic responses of the two cultivars and the expression of photoperiod pathway genes were analyzed accordingly. The photoperiod insensitive（PI） genotype plants flower early under SD; meanwhile, the abnormal expression of the Ppd-D1 a allele is accompanied with an increase in Ta FT1 expression and the TaCO expression variation. The results would facilitate molecular breeding in wheat.

关键词： wheat photoperiod spike differentiation heading gene expression Ppd-D1

Influence of DNA methyltransferase 3b on FHIT expression and DNA methylation of the FHIT promoter region in hepatoma SMMC-7721 cells

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Hepatobiliary & Pancreatic Diseases International 2009年第3期8卷 273-277页

作者： Wang, Jia-xiang Zhang, yong-Gan zhao, Long-Shuan Zhengzhou Univ Dept Surg Affiliated Hosp 1 Zhengzhou 450052 Peoples R China

BACKGROUND: Alterations in DNA methylation occur during the pathogenesis of human tumors. In this study, we investigated the influence of DNA methyltransferase 3b (DNMT3b) on fragile histidine trial (FHIT) expression and on DNA methylation of the FHIT promoter region in the hepatoma cell line SMMC-7721. METHODS: DNMT3b siRNA was used to down-regulate DNMT3b expression. DNMT3b and FHIT proteins were determined by Western blotting. Methylation-specific PCR was used to analyze the methylation status of the FHIT gene. RESULTS: After DNMT3b siRNA transfection, the expression of DNMT3b was inhibited in SMMC-7721 cells, and the expression of FHIT was significantly higher than that in the control group. There was no significant difference in methylation status between the DNMT3b siRNA transfected cells and control cells. CONCLUSION: DNMT3b may play an important role in regulation of FHIT expression in hepatoma SMMC-7721 cells, but not through methylation of the FHIT promoter. (Hepatobiliary Pancreat Dis Int 2009; 8: 273-277)

关键词： liver neoplasms DNA methyltransferase 3b fragile histidine trial methylation gene expression