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Identifying factors that influence soil heavy metals by using categorical regression analysis:A case study in Beijing,China

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Frontiers of Environmental Science & Engineering 2020年第3期14卷 1-14页

作者： Jun Yang Jingyun Wang Pengwei Qiao Yuanming zheng Junxing Yang Tongbin Chen Mei Lei xiaoming Wan Xiaoyong zhou Center for Environmental Remediation Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing 100101China University of Chinese Academy of Sciences Beijing 100049China Research Center for Eco-Environmental Sciences Chinese Academy of SciencesBeijing 100085China Beijing Key Laboratory of Remediation of Industrial Pollution Sites Environmental Protection Research Institute of Light IndustryBeijing 100048China

Identifying the factors that influence the heavy metal contents of soil could reveal the sources of soil heavy metal *** this study,a categorical regression was used to identify the factors that influence soil heavy ***,environmental factors were associated with soil heavy metal data,and then,the degree of influence of different factors on the soil heavy metal contents in Beijing was analyzed using a categorical *** results showed that the soil parent material,soil type,land use type,and industrial activity were the main influencing factors,which suggested that these four factors were important sources of soil heavy metals in *** addition,population density had a certain influence on the soil Pb and Zn *** distribution of soil As,Cd,Pb,and Zn was markedly influenced by interactions,such as traffic activity and land use type,industrial activity and population *** spatial distribution of soil heavy metal hotspots corresponded well with the influencing factors,such as industrial activity,population density,and soil parent *** this study,the main factors affecting soil heavy metals were identified,and the degree of their influence was ranked.A categorical regression represents a suitable method for identifying the factors that influence soil heavy metal contents and could be used to study the genetic process of regional soil heavy metal pollution.

关键词： Soil Heavy metal Influencing factor Categorical regression Identification method

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Design principles in mechanically adaptable biomaterials for repairing annulus fibrosus rupture:A review

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Bioactive Materials 2024年第1期31卷 422-439页

作者： Dan zhou Hongmei liu Zhaomin zheng Decheng Wu Guangdong Provincial Key Laboratory of Advanced Biomaterials Department of Biomedical EngineeringSouthern University of Science and TechnologyShenzhen518055China Department of Spine Surgery The First Affiliated HospitalSun Yat-Sen UniversityGuangzhou510080China Pain Research Center Sun Yat-Sen UniversityGuangzhou 510080China

Annulus fibrosus(AF)plays a crucial role in the biomechanical loading of intervertebral disc(IVD).AF is difficult to self-heal when the annulus tears develop,because AF has a unique intricate structure and biologic milieu in *** engineering is promising for repairing AF rupture,but construction of suitable mechanical matching devices or scaffolds is still a grand *** deeply know the varied forces involved in the movement of the native annulus is highly beneficial for designing biomimetic scaffolds to recreate the AF *** this review,we overview six freedom degrees of forces and adhesion strength on AF ***,we summarize the mechanical modalities to simulate related forces on AF and to assess the characteristics of *** finally outline some current advanced techniques to develop mechanically adaptable biomaterials for AF rupture repair.

关键词： Annulus fibrosus Forces Mechanical matching High tough High adhesion

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Accommodation of curtailed wind power by electric water heaters based on a new hybrid prediction approach

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Journal of Modern Power Systems and Clean Energy 2019年第3期7卷 525-537页

作者： Yang YU Zengqiang MI xiaoming zheng Da CHANG State Key Laboratory of Alternate Electrical Power System with Renewable Energy Sources North China Electric Power UniversityBaoding071003China Hebei Key Laboratory of Distributed Energy Storage and Micro-grid North China Electric Power UniversityBaoding071003China

Wind power curtailment is of great importance with the increase of large-scale wind power connected to the grid. A new concept of redundant wind power accommodated by dispatching electric water heaters(EWHs) is developed in the paper. Precise predictions of wind power and EWHs load power are the basis for this work. A hybrid multi-kernel prediction approach integrating an adaptive fruit fly optimization algorithm(AFOA)and multi-kernel relevance vector machine(MKRVM) is proposed to deal with the sample distribution of multisource heterogeneous features uncovered by an energy entropy method, where AFOA is used to determine the kernel parameters in MKRVM adaptively and avoid the arbitrariness. For the large computation of the prediction approach, parallel computation based on the Hadoop cluster is used to accelerate the calculation. Then, an economic dispatching model for accommodating wind power is built taking into account the penalty of curtailed wind power and the operation cost of EWHs. The proposedscheme is implemented in an intelligent residential *** results show that the optimization performance of the hybrid prediction approach is superior to those of four usual optimization algorithms in this case. Regular or orderly scheduling of EWHs enables accommodation of superfluous wind power and reduces dispatch cost.

关键词： Wind power curtailment Electric water heaters(EWH) Dispatching model Relevance vector machine Prediction model

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Simulation study for atomic size and alloying effects during forming processes of amorphous alloys

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Science China(Physics,Mechanics & Astronomy) 2004年第4期47卷 393-402页

作者： zheng Caixing liu Rangsu PENG Ping zhou Qunyi Department of Physics Hunan University Changsha 410082 China Department of Physics Hunan University Changsha 410082 China Department of Physics Hunan University Changsha 410082 China Department of Physics Hunan University Changsha 410082 China

A molecular dynamics (MD) simulation study has been performed for the solidification processes of two binary liquid alloys Ag6Cu4 and CuNi by adopting the quantum Sutton-Chen many-body potentials. By analyzing bond-types, it is demonstrated that at the cooling rate of 2×1012K/s, the CuNi forms fcc crystal structures, while the Ag6Cu4 forms amorphous structures. The original reason is that the atomic radius ratio (1.13) of the CuAg is bigger than that (1.025) of the CuNi. This shows that the atomic size difference is indeed the main factor for forming amorphous alloys. Moreover, for Ag60Cu40, corresponding to the deep eutectic point in the phase diagram, it forms amorphous structure easily. This confirms that as to the forming tendency and stability of amorphous alloys, the alloying effect plays a key role. In addition, having analyzed the transformation of microstructures by using the bond-type index and cluster-type index methods, not only the key role of the icosahedral configuration to the formation and stability of amorphous alloys can be explained, but also the solification processes of liquid metals and the characteristics of amorphous structures can be further understood.

关键词： amorphous alloys, solidification processes, atomic size effect, alloying effect, computer simulation.

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Unveiling a half-century mystery of molecular bases for three-line hybrid rice breeding system

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Journal of Integrative Plant Biology 2024年第1期66卷 3-6页

作者： xiaoming zheng Qian Qian State Key Laboratory of Crop Gene Resources and Breeding Chinese Academy of Agricultural SciencesBeijing 100081China Yazhouwan National Laboratory No.8 Huanjin RoadYazhou DistrictSanya 572024China

Rice(Oryza sativa L.)isa staplecropforhalf theworld's Ipopulation and an important contributor to world food *** discovery and application of cytoplasmic male sterility(CMS)and fertility restoration(Rf)genetic materials have allowed the production of three-line hybrid rice(Kim and Zhang,2018),successfully harnessing heterosis in *** major CMS and/or Rf systems are commonly used to produce three-line hybrid rice:Wild Abortive(CMS-WA),Boroll(CMS-BT),and Honglian(CMS-HL).Among these,the CMS-WA system is the most widely employed(Sattari et al.,2007;Chen and liu,2014;Huang et al.,2014).Several Rf genes from different CMS systems have been cloned in rice,including Rf4 for CMS-WA(Tang et al.,2014),Rf1a and Rf1b for CMS-BT(Wang et al.,2006),Rf5,and Rf6 for CMS-HL(Huet al.,2012;Huang et al.,2015),and Rf19for CMS-FA(Jiang et al.,2022).A molecular mechanism and evolutionary model for the CMS-WA gene WA352c have also been reported(Luo et al.,2013;Tang et al.,2017).

关键词： breeding fertility Wild

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Surface decarburization characteristics and relation between decarburized types and heating temperature of spring steel 60Si2MnA

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International Journal of Minerals,Metallurgy and Materials 2013年第8期20卷 720-724页

作者： Chao-lei Zhang Le-yu zhou Ya-zheng liu School of Materials Science and Engineering University of Science and Technology Beijing

The characteristics of complete and partial decarburizations in spring steel 60Si2MnA were systematically investigated, including the microstructure, the hardness gradient, and the formation mechanism. The relation between decarburized types and heating temperature of the steel was comprehensively discussed. It is found that heating temper- ature has an important influence on the decarburized types. With the rise of heating temperature, the decarburized types change from no decarburization to complete decarburization, complete and partial decarburizations, partial decarburiza- tion, and no decarburization.

关键词： spring steel decarburization temperature microstructure hardness

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Resource allocation in OFDMA heterogeneous networks for maximizing weighted sum energy efficiency

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Science China(Information Sciences) 2017年第6期60卷 200-211页

作者： xiaoming WANG Fuchun zheng Xia JIA Xiaohu YOU School of Telecommunication and Information Engineering Nanjing University of Posts and Telecommunications National Mobile Communications Research Laboratory Southeast University School of Systems Engineering University of Reading Tongda College of Nanjing University of Posts and Telecommunications

In this paper, a resource allocation algorithm for maximizing the weighted sum energy efficiency(EE) is investigated in orthogonal frequency division multiple access(OFDMA) heterogeneous networks(HetNets). We aim to balance the EE of macro cell and low power nodes by subchannel and power allocations. We formulate the problem as a nonlinear sum-of-ratios programming issue, and guarantee data rate requirements of users by using minimum rate constraints. Due to the nonconvexity of the problem, we develop a heuristic subchannel assignment algorithm, and then solve the power allocation problem by parameterized transformations and a first-order approximation based on an iterative algorithm. Numerical results illustrate the convergence and the effectiveness of the proposed algorithm.

关键词： resource allocation energy efficiency OFDMA heterogeneous network interference management

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Urban garbage disposal and management in China

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Journal of Environmental Sciences 2003年第4期15卷 531-540页

作者： JIANG Yuan KANG Mu yi liu zheng zhou Yan fang Institute of Resources Science Beijing Normal UniversityBeijing 100875China.

This paper, probing into the present situation of urban domestic garbage by analyzing its growing trend, compositional change and regional difference, reveals the problems existing in its disposal and management in China. Meanwhile, a questionnaire was conducted in five big cities around China for surveying urban residents' attitudes towards garbage disposal and management policies and measures. Results showed the output of urban domestic garbage in Chinese cities is ever increasing, and the recoverable materials and energy in garbage composition are also increasing. The population growth, economic development, and increase of residents' expenditure level are the main factors influencing the growing output and changing composition of the garbage. Information acquired from the questionnaire showed that majority of the urban residents are in favor of the garbage reduction policies and managerial measures and are willing to collaborate with municipal government in battling against garbage. Based on the analysis and questionnaire, some policymaking oriented suggestions such as operating the garbage disposal from a social welfare service to a sector of profit gaining enterprises, transferring the garbage management from passive end control to active source control, promoting the classified garbage collection in cities around China, and charging garbage fees for its cleanup and disposal, have also been put forward in the paper.

关键词： urban domestic garbage garbage collection garbage disposal garbage management

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FATIGUE LIFE PREDICTION OF RC BEAMS STRENGTHENED WITH PRESTRESSED CFRP UNDER CYCLIC BENDING LOADS

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Acta Mechanica Solida Sinica 2013年第1期26卷 46-52页

作者： Peiyan Huang Guangwan liu Xinyan Guo Hao zhou Xiaohong zheng School of Civil Engineering and Transportation South China University of Technology State Key Laboratory of Subtropical Building Science South China University of Technology

The application of prestressed carbon reinforced polymer （prestressed CFRP） in reinforced concrete （RC） members can improve the mechanical properties of strengthened structures and strengthening efficiency. This paper proposed a semi-empirical prediction fornmla of fatigue lives of the RC beams strengthened with prestressed CFRP under bending loads. The formula is established based on the fatigue life prediction method of RC beams and fatigue experimental data of non-prestressed CFRP reinforced beams done before. Fatigue effect coefficient of the formula was confirmed by the fatigue experiments of the RC beams strengthened with prestressed carbon fiber laminate （prestressed CFL） under cyclic bending loads. Fatigue lives of the strengthened beams predicted using the formula agreed well with the experimental data.

关键词： prestressed carbon fiber reinforced polymer (prestressed CFRP) carbon fiber laminate (CFL) fatigue effect coefficient life prediction bending load

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Do land utilization patterns affect methanotrophic communities in a Chinese upland red soil?

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Journal of Environmental Sciences 2010年第12期22卷 1936-1943页

作者： Yong zheng Xinzhan liu Limei Zhang Zhifeng zhou Jizheng He State Key Laboratory of Urban and Regional Ecology Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 China Key Laboratory of Systematic Mycology and Lichenology Institute of Microbiology Chinese Academy of Sciences Beijing 100101 China

Soil samples were collected from three plots under different land utilization patterns including degradation, farming, and restoration. The abundances of methanotrophs were quantified using real-time polymerase chain reaction （PCR） based on the pmoA and 16S rRNA genes, and the community fingerprint was analyzed using denaturing gradient gel electrophoresis （DGGE） aiming at pmoA gene. Significantly lower 16S rRNA and pmoA genes copies were found in the degradation treatment than in farming and restoration. Higher abundances of Type I than those of Type II methanotrophs were detected in all treatments, The treatment of farming was clearly separated from degradation and restoration according to the DGGE profile by cluster analysis. The lowest diversity indices were observed in the F （farming plot）, suggesting that the community structure was strongly affected by farming activities. There were significantly positive correlations between the copy numbers of pmoA also Type II-related 16S rRNA genes and soil available K content. Strong negative and positive correlations were found between Type I and soil pH, and available P content, respectively. We concluded that the vegetation cover or not, soil characteristics including pH and nutrients of P and K as a result of anthropogenic disturbance may be key factors affecting methanotrophic communities in upland soil.

关键词： DGGE land utilization methanotrophs prnoA real-time PCR

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