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Analytical Method for the Wave Diffraction of Asymmetrically Arranged Breakwaters

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China Ocean Engineering 2024年第5期38卷 797-808页

作者： zhou pei-xin ZHANG Hong-sheng College of Ocean Science and Engineering Shanghai Maritime UniversityShanghai 201306China Bureau of Transport of Beilun District of Ningbo Zhejiang 315800China

The layout forms of several breakwater structures can be generalized as asymmetrical arrangements in actual ***,the problem of wave diffraction around asymmetrically arranged breakwaters has not been adequately *** this study,we propose an analytical method of wave diffraction for regular waves passing through asymmetrically arranged breakwaters,and we use the Nyström method to obtain the analytical solution *** compared the results of this method with those of previous analytical solutions and with numerical results to demonstrate the validity of our *** also provided diffraction coefficient diagrams of breakwaters with different layout ***,we described the analytical expression for the problem of diffraction through long-wave incident breakwaters and presented an analysis of the relationship between the diffraction coefficients and the widths of breakwater *** analytical method presented in this study contributes to the limited literature on the theory of wave diffraction through asymmetrically arranged breakwaters.

关键词： regular waves breakwaters analytical method wave diffraction

DNA damaging effects of carbofuran and its main metabolites on mice by micronucleus test and single cell gel electrophoresis

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Science China(Life Sciences) 2005年第z1期48卷 40-47页

作者： zhou pei LIU Baofeng LU Yitong Department of Resource and Environment Science School of Agriculture and Biology Shanghai Jiaotong University Shanghai 201101China Department of Resource and Environment Science School of Agriculture and Biology Shanghai Jiaotong University Shanghai 201101China Department of Resource and Environment Science School of Agriculture and Biology Shanghai Jiaotong University Shanghai 201101China

The DNA damaging effects of the carbamate pesticide carbofuran and its four metabolites (carbofuranphenol, 3-ketocarbofuran, 3-hydrocarbofuran and nitrosocarbofuran) on mice were evaluated by single cell gel electrophoresis (SCGE) assay and micronucleus test. KM mice were exposed to test compounds with different doses of 0.1, 0.2 and 0.4mg/kg through intraperitoneal injection two times with an internal of 24 h, and then killed by cervical dislocation 6 h after the second injection. In SCGE assay, isolated mice peripheral blood lymphocytes were employed to determine DNA damaging degree after a 1 h treatment by test compounds and a following electrophoresis. Carbofuran and carbofuranphenol showed negative results in both test and had no obvious toxicity. 3-hydrocarbofuran and nitrosocarbofuran were positive.3-ketocarbofuran could not induce micronucleus formation but caused significant DNA migration in SCGE test. These tests revealed that 3-ketocarbofuran, 3-hydrocarbofuran and nitrosocarbofuran are potential mutagesis and further research is needed.

关键词： carbofuran metabolite, micronucleus, SCGE, DNA damage.

A modelling method for large-scale open spaces orientated toward coordinated control of multiple air-terminal units

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Building Simulation 2023年第2期16卷 225-241页

作者： pei zhou Songjie Wang Jintao zhou Syed Asad Hussain Xiaoping Liu Jiajia Gao Gongsheng Huang School of Civil Engineering Hefei University of TechnologyHefeiAnhuiChina Life Cycle Management Laboratory School of EngineeringUniversity of British Columbia(Okanagan Campus)KelownaBritish ColumbiaCanada Department of Building Environment&Energy Engineering Wuhan University of Science&TechnologyWuhanChina Department of Architectural and Civil Engineering City University of Hong KongTat Chee AvenueKowloonHong KongChina

The temperature distribution is always assumed to be homogeneous in a traditional singleinput-single-output(SISO)air conditioning control ***,the airflow inside is more complicated and *** study proposes a zonal temperature control strategy with a thermal coupling effect integrated for air-conditioned large-scale open *** target space was split into several subzones based on the minimum controllable air terminal units in the proposed method,and each zone can be controlled to its own set-point while considering the thermal coupling effect from its adjacent zones.A numerical method resorting to computational fluid dynamics was presented to obtain the heat transfer coefficients(HTCs)under different air supply *** relationship between heat transfer coefficient and zonal temperature difference was ***,currently available zonal models in popular software can be used to simulate the dynamic response of temperatures in large-scale indoor open *** studies showed that the introduction of HTCs across the adjacent zones was capable of enhancing the precision of temperature control of large-scale open *** could satisfy the temperature requirements of different zones,improve thermal comfort and at least 11%of energy saving can be achieved by comparing with the conventional control strategy.

关键词： large-scale open space zonal temperature control CFD thermal coupling heat transfer coefficient TRNSYS

Mrakia psychrophila ***.,a new species isolated from Antarctic soil

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2007年第4期8卷 260-265页

作者： XIN Ming-xiu zhou pei-jin College of Life Sciences Beijing Normal University Beijing 100875 China Institute of Microbiology Academia Sinica Beijing 100080 China

The yeast strain （Y18） was isolated from a soil sample collected from Fildes Peninsula, Antarctica. The strain is a psychrophilic yeast with optimum and maximum growth temperatures of 10 ℃ and 18 ℃, respectively. Teliospores were formed after 7 d on malt agar, when the germination of teliospores was observed. Both inositol and D-glucuronate were assimilated. Positive results of the DBB （diazonium blue B） color reaction, urease test, and starch formation were observed. The major CoQ is Qs. All results indicated that Y18 belongs to the genes of Mrakia. The 18S rDNA sequence analyses showed that Y18 is closely related to Mrakiafrigida. DNA-DNA relatedness study, and some biochemistry characteristics indicated that Y18 represents a new species for which Mrakia psychrophila sp. nov. is proposed.

关键词： Mrakiapsychrophila Psychrophilic yeast 18S rDNA sequence Teliospores

Effects of plant species coexistence on soil enzyme activities and soil microbial community structure under Cd and Pb combined pollution

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Journal of Environmental Sciences 2010年第7期22卷 1040-1048页

作者： Yang Gao pei zhou Liang Mao Yueer Zhi Chunhua Zhang Wanjun Shi School of Environmental Science and Engineering Shanghai Jiaotong University Shanghai 200240 China School of Agriculture and Biology Shanghai Jiaotong University Shanghai 200240 China Key Laboratory of Urban Agriculture (South) Ministry of Agriculture Shanghai 200240 China

The relationship between plant species coexistence and soil microbial communities under heavy metal pollution has attracted much attention in ecology. However, whether plant species coexistence could offset the impacts of heavy metal combined pollution on soil microbial community structure and soil enzymes activities is not well studied. The modified ecological dose model and PCR-RAPD method were used to assess the effects of two plant species coexistence on soil microbial community and enzymes activities subjected to Cd and Ph combined stress. The results indicated that monoculture and mixed culture would increased microbe populations under Cd and Pb combined stress, and the order of sensitivity of microbial community responding to heavy metal stress was： actinomycetes 〉 bacteria 〉 fungi. The respirations were significantly higher in planted soil than that in unplanted soil. The plant species coexistence could enhance soil enzyme activities under Cd and Pb combined. Furthermore, planted soil would be helpful to enhance soil genetic polymorphisms, but Cd and Pb pollution would cause a decrease on soil genetic polymorphisms. Mixed culture would increase the ecological dose 50% （ED50） values, and the ED50 values for soil enzyme activities decreased with increasing culture time. The dehydrogenase was most sensitive to metal addition and easily loses activity under low dose of heavy metal. However, it was difficult to fully inhibit the phoshpatase activity, and urease responded similarly with phosphatase.

关键词： ecological dose enzyme activities DNA RAPD heavy metal

Release behavior and kinetic evaluation of berberine hydrochloride from ethyl cellulose/chitosan microspheres

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Frontiers of Materials Science 2014年第4期8卷 373-382页

作者： Hui-Yun zhou pei-pei CAO Jie ZHAO Zhi-Ying WANG Jun-Bo LI Fa-Liang ZHANG Chemical Engineering & Pharmaceutics College Henan University of Science and Technology Luoyang 471023 China

Novel ethyl cellulose/chitosan microspheres （ECCMs） were prepared by the method of w/o/w emulsion and solvent evaporation. The microspheres were spherical, adhesive, and aggregated loosely with a size not bigger than 5 pm. The drug loading efficiency of berberine hydrochloride （BH） loaded in microspheres were affected by chitosan （CS） concentration, EC concentration and the volume ratio of V（CS）/V（EC）. ECCMs prepared had sustained release efficiency on BH which was changed with different preparation parameters. In addition, the pH value of release media had obvious effect on the release character of ECCMs. The release rate of BH from sample B was only a little more than 30% in diluted hydrochloric acid （dHCl） and that was almost 90% in PBS during 24 h. Furthermore, the drug release data were fitted to different kinetic models to analyze the release kinetics and the mechanism from the microspheres. The released results of BH indicated that ECCMs exhibited non-Fickian diffusion mechanism in dHCI and diffusion-controlled drug release based on Fickian diffusion in PBS. So the ECCMs might be an ideal sustained release system especially in dHCl and the drug release was governed by both diffusion of the drug and dissolution of the polymeric network.

关键词： ethyl cellulose (EC) chitosan (CS) microsphere release in vitro releasekinetics

Toric Parameterization Based Isogeometric Collocation Method for Planar Multi-Sided Physical Domains

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Journal of Systems Science & Complexity 2024年

作者： zhou pei ZHU Chungang School of Mathematical Sciences Dalian University of Technology Key Laboratory for Computational Mathematics and Data Intelligence of Liaoning Province

Isogeometric collocation method(IGC) shows high computational efficiency compared with isogeometric Galerkin method(IGG) when solving partial differential equations(PDEs). However, few studies about IGC have focused on multi-sided physical domains. In this paper, the authors propose a new IGC method based on toric parameterization(IGCT) for the multi-sided planar physical *** to the high order continuity of toric basis functions, the IGCT method shows more accurate numerical approximation. Moreover, the authors generalize the adaptive w-refinement method into IGCT(IGCT-w), in which the weights of basis functions in physical domains are optimized independently for geometry representation. The numerical accuracy of IGCT-w is significantly improved by an order of magnitude in comparison with IGCT method. To save the computational cost of IGCT-w, the authors devise a selection of weights scheme according to relative residuals. Finally, several numerical examples demonstrate the effectiveness and robustness of the proposed method.

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Plant diversity reduces the effect of multiple heavy metal pollution on soil enzyme activities and microbial community structure

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Frontiers of Environmental Science & Engineering 2012年第2期6卷 213-223页

作者： Yang GAO Chiyuan MIAO Jun XIA Liang MAO Yafeng WANG pei zhou Key Laboratory of Water Cycle and Related Land Surface Processes Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing 100101China State Key Laboratory of Earth Surface Processes and Resource Ecology College of Global Change and Earth System ScienceBeijing Normal UniversityBeijing 100875China State Key Laboratory of Urban and Regional Ecology Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China School of Agriculture and Biology Shanghai Jiao Tong UniversityShanghai 200240China

It is unclear whether certain plant species and plant diversity could reduce the impacts of multiple heavy metal pollution on soil microbial structure and soil enzyme activities. Random amplified polymorphic DNA （RAPD） was used to analyze the genetic diversity and microbial similarity in planted and unplanted soil under combined cadmium （Cd） and lead （Pb） pollution. A metal hyper- accumulator, Brassica juncea, and a common plant, Festuca arundinacea Schreb, were used in this research. The results showed that microorganism quantity in planted soil significantly increased, compared with that in unplanted soil with Cd and Pb pollution. The order of microbial community sensitivity in response to Cd and Pb stress was as follows： actinomycetes 〉 bacteria 〉 fungi. Respiration, phosphatase, urease and dehydrogenase activity were significantly inhibited due to Cd and Pb stress. Compared with unplanted soil, planted soils have frequently been reported to have higher rates of microbial activity due to the presence of additional surfaces for microbial colonization and organic compounds released by the plant roots. Two coexisting plants could increase microbe population and the activity of phosphatases, dehydrogenases and, in particular, ureases. Soil enzyme activity was higher in B. juncea phytoremediated soil than in F. arundinacea planted soil in this study. Heavy metal pollution decreased the richness of the soil microbial community, but plant diversity increased DNA sequence diversity and maintained DNA sequence diversity at highlevels. The genetic polymorphism under heavy metal stress was higher in B. juncea phytoremediated soil than in F. arundinacea planted soil.

关键词： enzyme activity soil DNA microbial popula-tion plant diversity heavy metal

Supersymmetric Electroweak Corrections to the Decay of the Heavy Chargino into the Light Chargino and Z Boson

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Communications in Theoretical Physics 2002年第8期38卷 173-180页

作者： zhou pei-Jun MA Wen-Gan ZHANG Ren-You WAN Lang-Hui Department of Modern Physics University of Science and Technology of China Hefei 230027 China Department of Modern Physics University of Science and Technology of China Hefei 230027 China Department of Modern Physics University of Science and Technology of China Hefei 230027 China Department of Modern Physics University of Science and Technology of China Hefei 230027 China

The supersymmetric electroweak corrections to the partial width of the decay x2+ → Z0x1-+, including thecontributions from the third generation quarks and squarks, are presented within the minimal supersymmetric standardmodel. With the reasonable parameters sets, which open this decay channel kinematically, the relative corrections canreach the value of ～ -6%. Therefore they should be taken into consideration for the precise experimental measurementat future colliders.

关键词： minimal supersymmetric standard model, chargino, electroweak correction