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About Some Aspects of Use of Optical Sensors for Monitoring the Aquatic Environment
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作者 Ferdenant Mkrtchyan Vladimiir Soldatov Maxim Mkrtchyan 《Journal of Environmental & Earth Sciences》 CAS 2024年第1期1-10,共10页
Multi-channel polarization optical technology is increasingly used for prompt monitoring of water systems.Optical devices during the assessment of water quality determine the intensity of light through the studied aqu... Multi-channel polarization optical technology is increasingly used for prompt monitoring of water systems.Optical devices during the assessment of water quality determine the intensity of light through the studied aquatic environment.Spectrophotometric devices measure the spectrum of weakening of light through the aquatic environment.Spectroellipsometric devices receive spectra in vertical and horizontal polarizations.The presented article develops an adaptive optical hardware and image system for monitoring water bodies.The system is combined.It consists of 2 parts:1)automated spectrophotometer-refractometer,and 2)adaptive spectroellipsometer.The system is equipped with a corresponding algorithmic and software,including algorithms for identifying spectral curves,databases and knowledge of spectral curves algorithms for solving reverse problems.The presented system is original since it differs from modern foreign systems by a new method of spectrophotometric and spectroellipsometric measurements,an original elemental base of polarization optics and a comprehensive mathematical approach to assessing the quality of a water body.There are no rotating polarization elements in the system.Therefore,this makes it possible to increase the signal-to-noise ratio and,as a result,improve measurement stability and simplify multichannel spectrophotometers and spectroellipsometers.The proposed system can be used in various water systems where it is necessary to assess water quality or identify the presence of a certain set of chemical elements. 展开更多
关键词 MONITORING aquatic environment Polarization optics Water object POLLUTANTS Spectral images Classification Identification
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Toxic effects of crude-oil-contaminated soil in aquatic environment on Carassius auratus and their hepatic antioxidant defense system 被引量:3
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作者 WANG Yuanyuan ZHOU Qixing +2 位作者 PENG Shengwei MA Lena Q NIU Xiaowei 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2009年第5期612-617,共6页
Under the indoor simulant conditions, toxic effects of crude-oil-contaminated soil which was put into aquatic environment on the young fishes Carassius auratus and their hepatic antioxidant system after a 20-d exposur... Under the indoor simulant conditions, toxic effects of crude-oil-contaminated soil which was put into aquatic environment on the young fishes Carassius auratus and their hepatic antioxidant system after a 20-d exposure were investigated. Results showed that the relationship between the mortality of C. auratus and the exposed doses could be divided into 3 phases: fishes exposed to the low dose groups (0.5-5.0 g/L) were dead due to the ingestion of crude-oil-contaminated soils in aquatic environment; at the medium dose groups (5.0-25.0 g/L) fishes were dead due to the penetration of toxic substances; at the high dose groups (25.0-50.0 g/L) fishes were dead due to environmental stress. The highest mortality and death speed were found in the 1.0 g/L dose group, and the death speed was sharply increased in the 50.0 g/L dose group in the late phase of exposure. The activities of superoxide dismutase (SOD), catalase (CAT) and glutathione S-transferase (GST) and the content of malaondialdehyde (MDA) in the hepatic tissues of C. auratus were induced significantly. The activity of SOD was increased and then decreased. It was significantly inhibited in the 50.0 g/L dose group. The activity of CAT was highly induced, and restored to a level which is little more than the control when the exposed doses exceeded 10.0 g/L. The activity of GST was the most sensitive, it was significantly induced in all dose groups, and the highest elevation was up to 6 times in the 0.5 g/L dose group comparing with the control. The MDA content was significantly elevated in the 50.0 g/L dose group, and the changes of the MDA content were opposite with the changes of GST activity. 展开更多
关键词 crude-oil-contaminated soil ECOTOXICOLOGY aquatic environment Carassius auratus antioxidant defense system
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DYNAMIC MODEL OF CROP GROWTH SYSTEM AND NUMERICAL SIMULATION OF CROP GROWTH PROCESS UNDER THE MULTI-ENVIRONMENT EXTERNAL FORCE ACTION
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作者 李自珍 王万雄 徐彩琳 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2003年第6期727-737,共11页
According to the biomechanic theory and method, the dynamic mechanism of crop growth under the external force action of multi_environment factors (light, temperature,soil and nutrients etc.) was comprehensively explor... According to the biomechanic theory and method, the dynamic mechanism of crop growth under the external force action of multi_environment factors (light, temperature,soil and nutrients etc.) was comprehensively explored.Continuous_time Markov(CTM) approach was adopted to build the dynamic model of the crop growth system and the simulated numerical method. The growth rate responses to the variation of the external force and the change of biomass saturation value were studied. The crop grew in the semiarid area was taken as an example to carry out the numerical simulation analysis, therefore the results provide the quantity basis for the field management. Comparing the dynamic model with the other plant growth model, the superiority of the former is that it displays multi_dimension of resource utilization by means of combining macroscopic with microcosmic and reveals the process of resource transition. The simulation method of crop growth system is advanced and manipulated. A real simulation result is well identical with field observational results. 展开更多
关键词 external force of environment crop growth dynamic model numerical simulation
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Strengthened Monitoring of H5 Avian Influenza Viruses in External Environment in Hubei, 2018 被引量:3
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作者 Lin-lin LIU Bin FANG +3 位作者 Xiao YU Xiang LI Ya-ke LEI Dan CHEN 《Current Medical Science》 SCIE CAS 2020年第1期63-68,共6页
The contamination status of H5 avian influenza viruses and distribution of subtypes of H5N1 and H5N6 in poultry-related environment of Hubei areas were investigated.Urban and rural live poultry markets,poultry farms,i... The contamination status of H5 avian influenza viruses and distribution of subtypes of H5N1 and H5N6 in poultry-related environment of Hubei areas were investigated.Urban and rural live poultry markets,poultry farms,intensive livestock farms and other monitoring types of 103 counties in 17 cities were selected in Hubei.Wiping samples from cage surface,wiping samples from chopping board,fecal specimens and other environmental samples were collected and tested by real-time RT-PCR using primers and probes of influenza A,avian influenza of H5,N1 and N6 from December 2017 to March 2018.The avian influenza virus positive rate was compared among different monitoring sites,samples,time and regions.Totally,7132 environmental samples were collected in 1634 monitoring points with a positive rate of 2.24%.The positive rate of H5 avian influenza virus was the highest in urban and rural live poultry markets(3.44%,x^2=61.329,P<0.05)in 6 monitoring sites and wiping samples from chopping board(5.46%,x^2=67.072,P<0.05)in 6 sample types.H5N6 avian influenza viruses were detected more in eastern than western Hubei,and H5N6 avian influenza viruses were detected only in Xiangyang city of western Hubei.There were important high-risk places of human infection with H5 avian influenza virus in urban and rural live poultry markets and the poultry slaughtering plants.H5N6 has been the predominant subtype of H5 avian influenza viruses in the eastern and western Hubei and H5N6 avian influenza viruses were still present in a few areas of Hubei.Outbreaks of human H5N1 and H5N6 avian influenza remain at risk in Hubei province. 展开更多
关键词 H5 avian influenza virus external environment strengthened monitoring
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Impact of light-weight external thermal insulation materials on building surrounding thermal environment in summer 被引量:6
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作者 李楠 罗国志 +1 位作者 李百战 黄彦祺 《Journal of Central South University》 SCIE EI CAS 2012年第6期1639-1644,共6页
The method for calculating wall surface heat storage coefficient was introduced,and the coefficients of several common walls with light-weight external thermal insulation materials and the traditional solid clay brick... The method for calculating wall surface heat storage coefficient was introduced,and the coefficients of several common walls with light-weight external thermal insulation materials and the traditional solid clay brick wall were calculated.In order to study the impact of light-weight external thermal insulation materials,a contrasting experiment was carried out between an external insulated room and an uninsulated room in August,2010,in Chongqing,China.The result shows that outside surface heat storage coefficient of the insulated wall is much less than that of the traditional wall.However,during sunny time,the surface temperature of external walls of the insulated room is obviously higher than that of the uninsulated room.In different orientations,due to different amounts of solar radiation and being irradiated in different time,the contrasting temperature difference(CTD) appears different regularity.In a word,using light-weight external thermal insulation materials has a negative impact on building surrounding thermal environment and people's health.Finally,some suggestions on how to eliminate the impact,such as improving the surface condition of the building envelop,and plating vertical greening,are put forward. 展开更多
关键词 保温材料 热环境 外墙 轻质 外部绝缘 夏季 墙体表面 蓄热系数
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Assessment of the conventional molybdenum-blue and magnesium-induced coprecipitation procedures in phosphorus measurement in various aquatic environments
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作者 LIU Sumei ZHAO Yingfei +3 位作者 REN Jingling ZHANG Jing SUN San JIN Jie 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2010年第1期42-51,共10页
Phosphorus (P) is an essential nutrient utilized by all organisms for energy transport and growth. Both the conventional molybdenum-blue method and the magnesium-induced coprecipitation (MAGIC) procedures were app... Phosphorus (P) is an essential nutrient utilized by all organisms for energy transport and growth. Both the conventional molybdenum-blue method and the magnesium-induced coprecipitation (MAGIC) procedures were applied for the measurement of dissolved inorganic phosphorus (DIP) and total dissolved phosphorus (TDP) in more than 840 water samples collected between 2003 and 2005, including seawater (the Huanghai Sea, the East China Sea, and the northern South China Sea), water from rivers and estuaries (the Changjiang, the Huanghe, and the major rivers emptying into the Jiaozhou Bay), groundwater (in the drainage basin surrounding the Jiaozhou Bay), rain-water, and aquaculture water samples. The MAGIC method allows the investigation of phosphorus distributions and cycling for systems in which DIP is below the detection limits of conventional methods. Comparison between the two methods demonstrated that the concentrations obtained with both methods were significantly correlated. The differences of DIP and TDP concentrations measured with the two methods were higher when the concentrations of DIP and TDP were lower, implying the lower reproducibility at low concentrations. The concentration differences increase with the increase in the proportion of DOP in TDP, which indicates that the discrepancy of DIP concentrations measured with the two methods increases when the DOP concentration is high. The discrepancies indicated that the composition of P compounds differs depending on sample sources and water type; it would be useful to infer the presence of different phosphorus compound pools from differences between the two methods. This study indicates the potential presence of a pool of alkaline-labile compounds for samples from rainwater and rivers and estuaries surrounding the Jiaozhou Bay; the potential presence of acid-labile compounds that were adsorbed by Mg(OH)2 for samples from the Changjiang Estuary, Huanghai Sea, East China Sea, and groundwater; the potential presence of a substantial pool of acid-labile compounds that were not adsorbed by Mg(OH)2 for samples from the Huanghe Estuary, aquaculture water, the East China Sea algal bloom water, and the northern South China Sea. 展开更多
关键词 PHOSPHORUS magnesium-induced coprecipitation conventional blue phosphomolybic acid assay various aquatic environments
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The impact of heavy metals on bacterial tolerance of antibiotic resistance and growth in the aquatic environment of Vietnam
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作者 Diep The Tai Mai Hoang Khanh Ngan +2 位作者 Chau Kim Hung Nguyen Ngoc Anh Thu Nguyen Thi Ngoc Nhi 《Infectious Diseases Research》 2022年第1期1-9,共9页
Heavy metals may induce bacterial antibiotic resistance and affect their growth in the ecosystem.In this study,we aim to determine bacterial growth and antibiotic resistance in the pressure of heavy metals.Observed th... Heavy metals may induce bacterial antibiotic resistance and affect their growth in the ecosystem.In this study,we aim to determine bacterial growth and antibiotic resistance in the pressure of heavy metals.Observed the changing morphology by gram staining was checked for bacterial toleration with heavy metal,developing of the colony form unit(CFU)was analysed bacterial kinetic growths and their biofilm formation.The disk diffusion test was used to perform bacterial susceptibility profiles with Ceftazidime(30μg),Ceftriaxone(30μg),Colistin sulfate(10μg),Meropenem or Imipenem(10μg),Ciprofloxacin(5μg)and Azithromycin(15μg)and the CLSI was applied for interpreting the data.The bacterial morphology remarkably changed from normal to short,round shape at a high concentration of heavy metals after 1 month.Their changing shape adapted to heavy metals by survival growing and resisted to Azithromycin,Ciprofloxacin,and Colistin without biofilm formation after 1 month,that was continued increasing after 2 months.The bacterial growth and antibiotic resistance were significant differences between provinces(P=0.01),type of bacterial species,and concentration of heavy metals.These results indicate that heavy metals are a crucial factor-driven for enhancing bacterial adaptation in pollution water resources and inducing their antimicrobial resistance in the aquatic environment. 展开更多
关键词 antimicrobial resistance heavy metals aquatic environment bacterial growth VIETNAM
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Progress in the research on aquatic environmental nonpoint source pollution in China 被引量:17
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作者 Bao Quansheng, Mao Xianqiang, Wang Huadong Institute of Environmental Sciences, Beijing Normal University, Beijing 1000875, China 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 1997年第3期76-83,共8页
In this paper, the authors reviewed the development process of China's research on aquatic environmental nonpoint pollution, and the situation of nonpoint source pollution in east China was also analyzed.
关键词 aquatic environment nonpoint source pollution pollution situation China.
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A Theoretical and Empirical Research on the Mediating Effect of Internal Entrepreneurial Environment
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作者 LI Qian-wen,ZHANG Yu-li 《研究与发展管理》 CSSCI 北大核心 2009年第1期112-112,共1页
The intensity of external uncertain environments has urged more and more companies to adopt theentrepreneurial orientation strategy. But to translate the corporate entrepreneurial orientation intoorganizational perfor... The intensity of external uncertain environments has urged more and more companies to adopt theentrepreneurial orientation strategy. But to translate the corporate entrepreneurial orientation intoorganizational performance, there must be certain transformation paths and the support from internalentrepreneurial environment. 展开更多
关键词 external rged MORE environment internalentrepreneurial
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China's External Economic Environment in the Early New Century
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作者 Zhou Rongkun Research Professor at the Division of World Economics Studies,China Institute of Contemporary International Relations. 《Contemporary International Relations》 2001年第2期1-8,共8页
Four Changes in World EconomyFirst,a new round of global economic growth is under way.In 2000,oil pricerose rapidly,stoek markets and exchange rates remained volatile and interestrates went up.All these disadvantages ... Four Changes in World EconomyFirst,a new round of global economic growth is under way.In 2000,oil pricerose rapidly,stoek markets and exchange rates remained volatile and interestrates went up.All these disadvantages did not undermine the foundations of worldeconomy,and the average growth rate of global gross domestic product(GDP) 展开更多
关键词 China’s external Economic environment in the Early New Century HIGH WILL
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Advancing the Understanding of Environmental Transformations, Bioavailability and Effects of Nanomaterials, an International US Environmental Protection Agency—UK Environmental Nanoscience Initiative Joint Program
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作者 Mitch M.Lasat Kian Fan Chung +5 位作者 Jamie Lead Steve McGrath Richard J.Owen Sophie Rocks Jason Unrine Junfeng Zhang 《Journal of Environmental Protection》 2018年第4期385-404,共20页
Nanotechnology has significant economic, health, and environmental benefits, including renewable energy and innovative environmental solutions. Manufactured nanoparticles have been incorporated into new materials and ... Nanotechnology has significant economic, health, and environmental benefits, including renewable energy and innovative environmental solutions. Manufactured nanoparticles have been incorporated into new materials and products because of their novel or enhanced properties. These very same properties also have prompted concerns about the potential environmental and human health hazard and risk posed by the manufactured nanomaterials. Appropriate risk management responses require the development of models capable of predicting the environmental and human health effects of the nanomaterials. Development of predictive models has been hampered by a lack of information concerning the environmental fate, behavior and effects of manufactured nanoparticles. The United Kingdom (UK) Environmental Nanoscience Initiative and the United States (US) Environmental Protection Agency have developed an international research program to enhance the knowledgebase and develop risk-predicting models for manufactured nanoparticles. Here we report selected highlights of the program as it sought to maximize the complementary strengths of the transatlantic scientific communities by funding three integrated US-UK consortia to investigate the transformation of these nanoparticles in terrestrial, aquatic, and atmospheric environment. Research results demonstrate there is a functional relationship between the physicochemical properties of environmentally transformed nanomaterials and their effects and that this relationship is amenable to modeling. In addition, the joint transatlantic program has allowed the leveraging of additional funding, promoting transboundary scientific collaboration. 展开更多
关键词 aquatic environment Consumer Products Manufactured NANOMATERIALS Predictive Models Terrestrial Ecosystem
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Late Cretaceous Aquatic Angiosperms from Jiayin,Heilongjiang,Northeast China 被引量:6
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作者 QUAN Cheng SUN Ge 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2008年第6期1133-1140,共8页
Three taxa of Late Cretaceous aquatic angiosperms, Queruexia angulata (Lesq.) Krysht., Cobbania corrugata (Lesq.) Stockey et al. and Nelumbites cf. extenuinervis Upchurch et al. from Jiayin of Heilongjiang, NE Chi... Three taxa of Late Cretaceous aquatic angiosperms, Queruexia angulata (Lesq.) Krysht., Cobbania corrugata (Lesq.) Stockey et al. and Nelumbites cf. extenuinervis Upchurch et al. from Jiayin of Heilongjiang, NE China, are described in detail. Among them, Cobbania and Nelumbites from the Upper Cretaceous in China are reported for the first time. The aquatic angiosperm assemblage of Queruexia-Cobbania-Nelumbites appears to imply a seasonal, warm and moist environment in the Jiayin area during the Santonian-Campanian time. 展开更多
关键词 aquatic angiosperm Late Cretaceous Jiayin Heilongjiang environment
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The levels of microbial diversity in dif ferent water layers of saline Chagan Lake,China 被引量:1
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作者 ZHANG Lei CAI Yanan +4 位作者 JIANG Miao DAI Jing GUO Xiyao LI Wei LI Yuehong 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2020年第2期395-407,共13页
Saline lakes represent a particularly interesting aquatic environment for harboring high microbial diversity.However,the microbial diversity in different states and locations of saline lake is often overlooked.We stud... Saline lakes represent a particularly interesting aquatic environment for harboring high microbial diversity.However,the microbial diversity in different states and locations of saline lake is often overlooked.We studied for the first time the diversity and relative composition of the microbial communities in the Chagan Lake,NE China,and investigated the dif ferences in microbial species and physical and chemical factors in different geographical localities of the lake.After extracting the total DNA of the sample,we tested the library with the established library,sequenced the qualified library with Illumina HiSeq 2500,and studied the bacterial diversity by 16 S rRNA targeted metagenomics analysis.Results reveal that the highest microbial abundance in Chagan Lake at genus level was Proteobacterium followed by Actinomycetes and Bacteroides.In addition,we compared the microbial composition within the lake using alpha-and beta-diversity indices,showing that both diversity and evenness were the highest in the middle of the lake and lowest in the west of lake areas,and in the upper,middle,and lower depth of water columns,the low water column had the highest species number in the whole water environment,but the dif ference was not significant.We believe that physicochemical factors contribute to the formation of microbial community composition and diversity.In aquaculture industry,it is impossible apply horticulture for making full use of the spatial dif ferences in the microbial composition of the water.Therefore,combining cultured aquatic animal with the most suitable microbial species is a good way to boost the breeding ef fect for greater economic value. 展开更多
关键词 saline lake aquatic environment microbial diversity physical and chemical factors Chagan Lake
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Molecular Phylogeny and Phenotypic Characterization of Yeasts with a Broad Range of pH Tolerance Isolated from Natural Aquatic Environments 被引量:1
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作者 Naoto Urano Ayaka Shirao +3 位作者 Yuka Naito Masahiko Okai Masami Ishida Masachika Takashio 《Advances in Microbiology》 2019年第1期56-73,共18页
In this study, yeasts with broad range of pH tolerance were isolated and characterized from natural aquatic environments in Japan. Only a few basic and application studies of alkali-tolerant yeasts have been reported,... In this study, yeasts with broad range of pH tolerance were isolated and characterized from natural aquatic environments in Japan. Only a few basic and application studies of alkali-tolerant yeasts have been reported, despite the unmet industrial needs. First, we surveyed alkali-tolerant yeasts from natural aquatic environments at pH 7.6 - 9.4. We isolated 35 yeast strains that grew in pH 9.0 medium, from seven genera and nine species: 25 strains (N1, N2, through N6, N9, K1, K3 through K19) were Rhodotorula mucilaginosa;one (N7) was Rhodosporidium fluvial;one (N8) was Scheffersomyces spartinae;two (N10 and N13) were Wicherhamonyces anomalus;one (N11) was Cyberlindnera saturnus;one (S1) was Candida sp.;two (S2 and S4) were Candida intermedia;one (S3) was Candida quercuum;and one (K2) was Cryptococcus liquefacience. We examined the effects of pH on the growth of representative yeast strains. Strains K12 and S4 showed high growth at pH 3 - 10. Strains N7, N8, N10, N11, and S3 showed high growth at pH 3 - 9. Strains K2 and S1 showed high growth at pH 4 - 8. All nine of these strains had neutralizing activities from acidic media at pH 3 - 5 to pH 6 - 8. We previously isolated acid-tolerant yeasts (Cryptococcus sp. T1 [1] and Candida intermedia CeA16 [2]) from extremely acidified environments;they showed high growth at pH 3 - 9 and neutralizing activities of acidic media by releasing ammonium ions. Thus, alkali-tolerant yeasts and acid-tolerant yeasts were found to be similar species and have both high growth at a broad range of pH and neutralizing activities of acid media. Previously, we also isolated acid-tolerant, acid-neutralizing yeasts from neutral natural environments (26 strains, 12 species) [3]. Next, we constructed the phylogenetic trees of both acid-tolerant yeasts and alkali-tolerant yeasts. All were situated in the same classification position. Similar yeast species with a broad range of pH tolerance were living in natural aquatic environments at pH values from alkali to acid. 展开更多
关键词 pH TOLERANCE YEAST Species aquatic environment PHYLOGENETIC Tree FERMENTATION
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A STUDY ON QUALITY OF AQUATIC ENVIRONMENT IN TUMEN RIVER AREA
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作者 朱颜明 黎劲松 卢学强 《Chinese Geographical Science》 SCIE CSCD 1998年第2期31-40,共10页
ASTUDYONQUALITYOFAQUATICENVIRONMENTINTUMENRIVERAREA①ZhuYanming(朱颜明)ChangchunInstituteofGeography,theChineseA... ASTUDYONQUALITYOFAQUATICENVIRONMENTINTUMENRIVERAREA①ZhuYanming(朱颜明)ChangchunInstituteofGeography,theChineseAcademyofSciences,... 展开更多
关键词 POLLUTION sources aquatic environment QUALITY environmental FORECAST Tumen RIVER
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Diffusion dynamics in external noise-activated non-equilibrium open system-reservoir coupling environment
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作者 王春阳 《Chinese Physics B》 SCIE EI CAS CSCD 2013年第7期334-338,共5页
The diffusion process in an external noise-activated non-equilibrium open system–reservoir coupling environment is studied by analytically solving the generalized Langevin equation. The dynamical property of the syst... The diffusion process in an external noise-activated non-equilibrium open system–reservoir coupling environment is studied by analytically solving the generalized Langevin equation. The dynamical property of the system near the barrier top is investigated in detail by numerically calculating the quantities such as mean diffusion path, invariance, barrier passing probability, and so on. It is found that, comparing with the unfavorable effect of internal fluctuations, the external noise activation is sometimes beneficial to the diffusion process. An optimal strength of external activation or correlation time of the internal fluctuation is expected for the diffusing particle to have a maximal probability to escape from the potential well. 展开更多
关键词 external noise DIFFUSION non-equilibrium open environment
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Numerical simulation of stratified turbulent two-phase flow in aquatic environment
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作者 Shen, Yong-Ming Wang, Ya-Ling Liang, Chuan 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2000年第2期24-28,共5页
The two fluid model of stratified turbulent two phase flow in aquatic environment is developed in this paper. The motion of each phase is described by a unified multi fluid model in an Eulerian coordinate system. T... The two fluid model of stratified turbulent two phase flow in aquatic environment is developed in this paper. The motion of each phase is described by a unified multi fluid model in an Eulerian coordinate system. The laws of turbulent transportation for each phase, and the restriction of each other between the two phases are completely simulated. The complex two phase turbulence with strong buoyancy effects is selected to examine numerically. The extensive experimental data obtained in stratified flow are used here. Comparison of the results of numerical simulation with the experimental data is conducted. It has shown that the results of numerical simulation are satisfactory. 展开更多
关键词 stratified flow two phase turbulence two fluid model aquatic environment CLC number: X131 2 Document code: A
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Perspective of World Economy and China's External Economic Environment
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作者 Tao Jian Chen Fengying Zhao Hongtu Zhang Yuncheng Jiang Yong Liang Jianwu Ni Jianjun Li Hongyan 《Contemporary International Relations》 2003年第12期31-63,共33页
Owing to a series of impacts of the "9·11 terrorist attack," the accounting scandals of big companies, Iraq War and the SARS crisis in the past two years, the world economy that might have rebounded for... Owing to a series of impacts of the "9·11 terrorist attack," the accounting scandals of big companies, Iraq War and the SARS crisis in the past two years, the world economy that might have rebounded forcefully has been on a wavering process of slow recovery. 展开更多
关键词 of AS for Perspective of World Economy and China’s external Economic environment that been THAN World into HAVE WILL
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ASSESSMENT OF 17β-ESTRADIOL IN AQUATIC ENVIRONMENTS AROUND KLANG VALLEY,MALAYSIA
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作者 Ahmad Ismail Syaizwan Zahmir Zulkifli +3 位作者 Ferdius Mohamat Yusuff Usuki Yasuteru Kitajima Sachiko Arizono Koji 《湿地科学》 CSCD 2007年第4期322-325,共4页
This study was conducted to assess the existing concentration of 17β-estradiol(E2)in the surface water samples collected from rivers and lakes around Klang Valley,Malaysia.E2,which is a natural feminizing chemical pr... This study was conducted to assess the existing concentration of 17β-estradiol(E2)in the surface water samples collected from rivers and lakes around Klang Valley,Malaysia.E2,which is a natural feminizing chemical produced in female organisms,regularly used to compare with other environmental estrogens because they behave similarly and react effectively as a hormone at a very low concentration.It was found that the average concentration of E2 in the aquatic environment of Klang Valley was(14.08 ±3.67)pg/mL,which was 14 times higher than those in the Japanese aquatic environment in this study.The river system had the average concentration of(20.02±5.26)pg/mL while the lake had an average concentration of(5.91±3.39)pg/mL.The E2 concentration was presumed high if the sources occurred nearby the area.Current levels of E2 in the aquatic environment may possess threats to existing aquatic organisms.Since high level of E2 has been discovered in the aquatic environment around Klang Valley,further studies and monitoring of E2 and other EDCs concentrations are needed to determine their levels in Malaysian aquatic environment and help to control these chemicals pollution in the aquatic environment. 展开更多
关键词 水生环境 马来群岛 地表水 峡谷 17Β-雌二醇 评估
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The Audit of Business Strategy
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《Economics World》 2017年第4期316-321,共6页
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