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Synergistic degradation of pyrene and volatilization of arsenic by cocultures of bacteria and a fungus

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Frontiers of Environmental Science & Engineering 2013年第2期7卷 191-199页

作者： shuang LIU Yanwei hou Guoxin SUN State Key Laboratory of Urban and Regional Ecology Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 China School of Environment Tsinghua University Beijing 100084 China Department of Environmental Science and Technology College of Chemical Engineering Huaqiao University Xiamen 361021 China

The combination of two bacteria （Bacillus sp. PY1 and Sphingomonas sp. PY2） and a fungus （Fusarium sp. PY3）, isolated from contaminated soils near a coking plant, were investigated with respect to their capability to degrade pyrene and volatilize arsenic. The results showed that all strains could use pyrene and arsenic as carbon and energy sources in a basal salts medium （BSM）, with the combined potential to degrade pyrene and volatilize arsenic. Bacillus sp. PY1, Sphingomonas sp. PY2 and Fusarium sp. PY3 were isolated from the consortium and were shown to degrade pyrene and volatilize arsenic independently and in combination. Fungal-bacterial cocul- ture has shown that the most effective removal of pyrene was 96.0% and volatilized arsenic was 84.1% after incubation in liquid medium after 9 days culture, while bioremediation ability was 87.2% in contaminated soil with 100 mg-kg-1 pyrene. The highest level of arsenic volatilization amounted to 13.9% of the initial As concentration in contaminated soil after 63 days. There- fore, a synergistic degradation system is the most effective approach to degrade pyrene and remove arsenic in contaminated soil. These findings highlight the role of these strains in the bioremediation of environments contaminated with pyrene and arsenic.

关键词： pyrene arsenic bioremediation bacteria,fungus

A taxonomic study on Endotricha Zeller （Lepidoptera： Pyralidae： Pyralinae） in China

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Insect Science 2005年第4期12卷 297-305页

作者： shuang-shuang WANG hou-HUN LI College of Life Sciences Nankai University Tianjin China

A checklist of 30 species ofEndotricha Zeller in China is presented in this paper. Six species （E. dumalis sp. nov., E. lunulata sp. nov. E. medogana sp. nov., E. nigra sp. nov., E. purpurata sp. nov. and E. simipunicea sp. nov.） are new to science and three （E. admirabilis Kirpichnikova, E. fuscobasalis Ragonot and E. valentis Kirpichnikova） are recorded for the first time in China. The adult features and genital structures of the new species are illustrated and a key to the Chinese species is given.

关键词： Lepidoptera Pyralidae Endotricha new species systematics

An Approximation Algorithm for P-prize-collecting Set Cover Problem

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Journal of the Operations Research Society of China 2023年第1期11卷 207-217页

作者： Jin-shuang Guo Wen Liu Bo hou School of Mathematical Sciences Hebei Key Laboratory of Computational Mathematics and ApplicationsHebei Normal UniversityShijiazhuang050024HebeiChina

In this paper,we consider the P-prize-collecting set cover(P-PCSC)problem,which is a generalization of the set cover *** this problem,we are given a set system(U,S),where U is a ground set and S⊆2U is a collection of subsets satisfying∪S∈SS=*** subset in S has a nonnegative cost,and every element in U has a nonnegative penalty cost and a nonnegative *** goal is to find a subcollection C⊆S such that the total cost,consisting of the cost of subsets in C and the penalty cost of the elements not covered by C,is minimized and at the same time the combined profit of the elements covered by C is at least P,a specified profit *** main work is to obtain a 2f+ε-approximation algorithm for the P-PCSC problem by using the primal-dual and Lagrangian relaxation methods,where f is the maximum frequency of an element in the given set system(U,S)andεis a fixed positive number.

关键词： P-prize-collecting set cover problem Approximation algorithm Primal-dual Lagrangian relaxation

Revise Thermal Winds of Remnant Neutron Stars in Gamma-Ray Bursts

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Research in Astronomy and Astrophysics 2023年第9期23卷 142-147页

作者： shuang Du Tingting Lin Shujin hou Renxin Xu School of Mathematics and Computer Tongling UniversityTongling 244061China School of Foundation Zhejiang Shuren UniversityShaoxing 312028China School of Physics and Electronic Engineering Nanyang Normal UniversityNanyang 473061China School of Physics Peking UniversityBeijing 100871China Kavli Institute for Astronomy and Astrophysics Peking UniversityBeijing 100871China

It seems that the wealth of information revealed by the multi-messenger observations of the binary neutron star(NS)merger event,GW170817/GRB 170817A/kilonova AT2017gfo,places irreconcilable constraints to models of the prompt emission of this gamma-ray burst(GRB).The observed time delay between the merger of the two NSs and the trigger of the GRB and the thermal tail of the prompt emission can hardly be reproduced by these models *** argue that the merger remnant should be an NS(last for,at least,a large fraction of 1 s),and that the difficulty can be alleviated by the delayed formation of the accretion disk due to the absorption of high-energy neutrinos emitted by the NS and the delayed emergence of effective viscosity in the ***,we extend the consideration of the effect of the energy deposition of neutrinos emitted from the *** the NS is the central object of a GRB with a distance and duration similar to that of GRB 170817A,thermal emission of the thermal bubble inflated by the NS after the termination of accretion may be *** our scenario is verified,it would be of interest to investigate the cooling of nascent NSs.

关键词： (stars )gamma-ray burst general-(stars )gamma-ray burst individual(..,...)-stars neutron

Neutral responses of plant community Ca concentration to nitrogen enrichment in a semiarid grassland

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Journal of Plant Ecology 2022年第2期15卷 286-293页

作者： shuang-Li hou Xiao-Tao Lü Jun-Jie Yang Erguna Forest-Steppe Ecotone Research Station CAS Key Laboratory of Forest Ecology and ManagementInstitute of Applied EcologyChinese Academy of SciencesShenyang 110016China State Key Laboratory of Vegetation and Environmental Change Institute of BotanyChinese Academy of SciencesBeijing 100093China

Calcium(Ca)is an essential nutrient for plant growth and Ca concentrations in forage have important implications for ruminant diet and *** remains an open question whether forage Ca concentration would be decreased by increasing nitrogen(N)*** manipulated the increasing rates of N addition(2008–2015)in a semiarid grassland,northern *** Ca concentrations for all species were examined in each plot under N *** Ca concentrations at functional group and community levels were calculated based on the concentration of each species presented and their relative biomass in each *** found that community-level Ca concentration remained stable across a gradient of wide-ranged N addition rates,although Ca concentration at both species and functional group levels showed negative responses to N *** that forbs had higher Ca concentration than grasses,the increasing relative biomass of forbs canceled out the negative responses of species-level and functional group-level Ca *** results further showed that community Ca pool showed a positive but saturating response to N addition,with a threshold at the rate of 10 g N m^(−2)yr^(−1).Our findings highlight the role of changes in plant relative biomass in controlling the responses of forage Ca concentration and stock to N enrichment.

关键词： calcium stock community composition ecological processes global changes nitrogen deposition temperate steppe

黄芩苷与苦参碱分子间相互作用的量子化学计算与验证

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原子与分子物理学报 2025年第4期42卷 8-14页

作者：董志舒启江田爽王皎侯安国王文苹云南中医药大学中药学院云南省南药可持续利用重点实验室昆明650500

为探究苦参碱能极大增强黄芩苷在水中的溶解度的原因,采用量子计算对二者反应过程及共存状态进行分析,并使用单晶衍射和红外图谱验证计算结果.本研究表明,黄芩苷和苦参碱并非简单的以非共价作用相结合,二者存在质子转移现象,反应生成黄... 详细信息

为探究苦参碱能极大增强黄芩苷在水中的溶解度的原因,采用量子计算对二者反应过程及共存状态进行分析,并使用单晶衍射和红外图谱验证计算结果.本研究表明,黄芩苷和苦参碱并非简单的以非共价作用相结合,二者存在质子转移现象,反应生成黄芩苷阴离子和苦参碱阳离子,以静电作用为主导形成共无定型物,导致水溶性极大增加.

关键词：苦参碱黄芩苷质子转移离子共无定型物

Influences of Cooling Rate After Solution Treatment on Microstructural Evolution and Mechanical Properties of Superalloy Rene 80

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Acta Metallurgica Sinica(English Letters) 2017年第3期30卷 261-271页

作者： shuang Gao Jie-Shan hou Kai-Xin Dong Lan-Zhang Zhou Institute of Metal Research Chinese Academy of SciencesShenyang 110016 China

Influences of the cooling rate after solution treatment on microstructural evolution and mechanical properties of Rene 80 nickel-based superalloy were investigated by optical microscopy, scanning electron microscopy, transmission electron microscopy and mechanical test. Results showed that the high cooling rate decreased the size of secondary γ＇particles in the supersaturated matrix, but led to a high coarsening rate of γ＇ particles during subsequent aging treatment. Despite various coarsening rates, the size and morphology of γ＇ particles in the final microstructures of all samples were close due to the long enough holding time to an equilibrium state. During the aging of 870 ℃/2 h, primary MC started to decompose with the carbide reaction： MC ＋ γ＇ --＊ MrC or M23C6 -t- γ＇. And a number of observations showed that the coarsening of γ＇ particles on grain boundaries resulted in the depletion of γ＇ during aging treatment. The test results indicated that high cooling rate resulted in the presence of quench crack, and the air cooling method following solution treatment was an optimum heat treatment method for Rene 80.

关键词： Ni-based superalloy Cooling rate Precipitates Ripening theory Heat treatment Microstructural evolution

Characterization and performance of graphene-PbSe thin film heterojunction

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Rare Metals 2021年第1期40卷 219-224页

作者： Bo He Yi-Xuan Ren Tian-Jun Dai shuang hou Xing-Zhao Liu School of Electronics Science and Engineering University of Electronic Science and Technology of ChinaChengdu 611731China State Key Laboratory of Electronic Thin Films and Integrated Devices Chengdu 611731China

An infrared detector with high responsivity based on graphene-PbSe thin film heterojunction was ***-quality PbSe thin film and graphene were prepared by molecular beam epitaxy and chemical vapor deposition,*** physical characteristics of PbSe thin film and graphene were performed using X-ray diffraction(XRD),X-ray photoelectron spectroscopy(XPS)and Raman *** photo transistor using PbSe thin film as a sensitizer and graphene as a channel to transport excitons exhibits peak responsivity and detectivity up to~420 A·W^(-1) and 5.9×10^(11) Jones(radiation intensity:0.75 mW·cm^(-2))at room temperature in the near-infrared(NIR)region,*** high optical response is attributed to the photo-excited holes transferring from PbSe film to graphene under ***,it is revealed that the responsivity of graphene-PbSe photo transistor is gate-tunable which is important in photodetectors.

关键词： PbSe Graphene Heterojunction Infrared photodetectors

Perturbation to Symmetries and Adiabatic Invariants for Generalized Birkhoffian Systems on Time Scales

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Wuhan University Journal of Natural Sciences 2024年第3期29卷 263-272页

作者： hou shuang SONG Chuanjing School of Mathematical Sciences Suzhou University of Science and TechnologySuzhou 215009JiangsuChina

Time scale is a new and powerful tool for dealing with complex dynamics problems. The main result of this study is the exact invariants and adiabatic invariants of the generalized Birkhoffian system and the constrained Birkhoffian system on time scales. Firstly, we establish the differential equations of motion for the above two systems and give the corresponding Noether symmetries and exact invariants. Then, the perturbation to the Noether symmetries and the adiabatic invariants for the systems mentioned above under the action of slight disturbance are investigated, respectively. Finally, two examples are provided to show the practicality of the findings.

关键词： time scale generalized Birkhoffian system Noether symmetry perturbation and adiabatic invariants