OALib Journal期刊

ISSN: 2333-9721




2019 ( 8 )

2018 ( 68 )

2017 ( 76 )

2016 ( 62 )


匹配条件: “ Chaosheng Zhu” ,找到相关结果约26816条。
The Asymptotic Behavior of Solutions for 3D Globally Modified Bénard Problem with Delay  [PDF]
Xia Hou, Chaosheng Zhu
Open Access Library Journal (OALib Journal) , 2019, DOI: 10.4236/oalib.1105163
In this paper, we mainly study the existence and uniqueness of solutions and the asymptotic behavior of solutions for three-dimensional globally modified Bénard systems with delays under local Lipschitz conditions.
Spatial distribution of copper content in sediments of the Yangtze River system
Chaosheng Zhang,Shen Zhang,Jianbang He
Chinese Science Bulletin , 1997, DOI: 10.1007/BF02882763
Geochemical characteristics of rare earth elements in Wuhan section of the Yangtze River
Wang Lijun,Zhang Shen,Zhang Chaosheng,
Wang Lijun
,Zhang Shen,Zhang Chaosheng,Li Xiuxia

环境科学学报(英文版) , 1995,
Abstract: The contents and speciation characteristics of rare earth elements(REE)in Wuhan section of the Yangtze River were analysed by neutron activation analysis (NAA).The contents of solvable fraction of REE in the river are very limited ,with the same results as other rivers. On the other hand,the content of suspend- ed fraction of REE in the river varies in a wide range. It varies with the variation of suspended matter in the water.The distribution patterns showed significant light REE enrichment and relative Eu-depletion. The speciation characteristics of REE in the sediments or suspended matter are quite similar, with the main amount in residual form. The amount of five forms obey the following order:residual> > bound to organic matter, bound to Fe-Mn oxides > bound to carbonates > > exchangeable. Compared with light and heavy EE,the mediate REE(Eu, Sm, Tb)have relatively low percentages in the residual form and high in the forms of bound to organic matter and Fe-Mn oxldes. The water bodies in Wuhan section of the Yangtze Riv- er have not been polluted by REE.
Contamination and Spatial Variation of Heavy Metals in the Soil-Rice System in Nanxun County, Southeastern China
Keli Zhao,Weijun Fu,Zhengqian Ye,Chaosheng Zhang
International Journal of Environmental Research and Public Health , 2015, DOI: 10.3390/ijerph120201577
Abstract: There is an increasing concern about heavy metal contamination in farmland in China and worldwide. In order to reveal the spatial features of heavy metals in the soil-rice system, soil and rice samples were collected from Nanxun, Southeastern China. Compared with the guideline values, elevated concentrations of heavy metals in soils were observed, while heavy metals in rice still remained at a safe level. Heavy metals in soils and rice had moderate to strong spatial dependence (nugget/sill ratios: 13.2% to 49.9%). The spatial distribution of copper (Cu), nickel (Ni), lead (Pb) and zinc (Zn) in soils illustrated that their high concentrations were located in the southeast part. The high concentrations of cadmium (Cd) in soils were observed in the northeast part. The accumulation of all the studied metals is related to the long-term application of agrochemicals and industrial activities. Heavy metals in rice showed different spatial distribution patterns. Cross-correlograms were produced to quantitatively determine the spatial correlation between soil properties and heavy metals composition in rice. The pH and soil organic matter had significant spatial correlations with the concentration of heavy metals in rice. Most of the selected variables had clear spatial correlation ranges for heavy metals in rice, which could be further applied to divide agricultural management zones.
Background contents of heavy metals in sediments of theYangtze River system and their calculation methods
Zhang Chaosheng,Zhang Shen,Zhang Licheng,Wang Lijun,
Zhang Chaosheng
,Zhang Shen,Zhang Licheng,Wang Lijun

环境科学学报(英文版) , 1995,
Abstract: BackgroundcontentsofheavymetalsinsedimentsoftheYangtzeRiversystemandtheircalculationmethodsZhangChaosheng,ZhangShen,ZhangLich...
Speciation of organic phosphorus in a sediment profile of Lake Taihu I: Chemical forms and their transformation
Di Xu,Shiming Ding,Bin Li,Xiuling Bai,Chengxin Fan,Chaosheng Zhang,
Di Xu
,Shiming Ding,Bin Li,Xiuling Bai,Chengxin Fan,Chaosheng Zhang

环境科学学报(英文版) , 2013,
Abstract: Organic phosphorus (nonreactive P, NRP) is a major component of P in sediments, but information about its chemical forms and dynamic transformation is limited. The chemical forms and dynamic behaviors of NRP in a sediment profile from Lake Taihu, a freshwater and eutrophic lake in China, were investigated. Five forms of NRP in the sediments were extracted based on a chemical fractionation technique, including easily labile NRP (NaHCO3-NRP), reactive metal oxide-bound NRP (HCl-NRP), humic acid-associated NRP (NaOH-NRPHA), fulvic acid-associated NRP (NaOH-NRPFA) and residual NRP (Res-TP). There were notable transformations with increasing sediment depth from the labile NaHCO3-NRP and NaOH-NRP pools to the recalcitrant HCl-NRP and Res-TP pools, which caused the NRP to become increasingly recalcitrant as the early diagenetic processes proceeded. Further analyses showed that the relative changes in contents of organic matter and reactive Fe oxides in the sediment profile triggered a competition for binding NRP fractions and led to the transformation of NRP. The results highlighted the importance of abiotic processes in regulating the diagenesis of organic P and its stability in sediments.
Effect of nitrite on performance of denitrifying phosphorus removal bacteria

Fang Qian,Zhang Chaosheng,Zhang Hong,

环境工程学报 , 2009,
Abstract: To investigate the effect of nitrite on the performance of denitrifying phosphorus removal bacteria(DPB),the inhibition of nitrite on DPB and the acclimatizing process of DPB using nitrite as electron acceptor were studied respectively in two SBR treating synthetic wastewater.The results indicated that the denitrifying phosphorus removal performance of non-acclimatized DPB is inhibited remarkably when the concentration of nitrite is more than 20 mg/L.Although the acclimatized DPB using nitrite as electron a...

Tao Shu Cui Jun Zhang Chaosheng,

地理学报 , 1990,
Abstract: Spectroscopic examination of humic substances from river, lake and sea water as well as from river and lake sediments in the UV-VIS region indicated that the E240/E420) ratios of water humic substances differ significantly from those of sediment humic substances. A cluster analysis based on the absorption spectra of the humic substances revealed a similar fact. Considering the humic substances from fresh water and sea water respectively, linear relationship between the optical density and the total organic carbon content of the samples implied that a spectrophotometric method (e.g. at 220 nm) for determination of humic substances concentration is possible.
A Study on the Reason of the Low Flourine Content in Groundwater in Southeast China

Chen Jingsheng,Yin song,Zhang Chaosheng,

环境科学 , 1992,
Abstract: Total flourine content and water extractable flourine content in zonal soils developed on granite from northeast China, north China, middle China and south-east China were compared, and the adsorption capacity for flourine anion of these soils were studied. The total flourine content in soils decreases from north to south, with the lowest in lateritic soil and laterite, and the water extrac-table flourine content varies in the same way. Adsorption experiment results show that in the eastern part of China, adsorption capacity of soils for flourine anion increases successively from brown soil, yellow soil to red soil and laterite. Considering from the viewpoint of geochemistry, the reason for low flourine content in water resources in south-east China lies on: (1) the heavy leaching of flourine during the process of the, weathering of granite into soils. (2) the high hydroxyl content of the soils in southeast China resulting in high exchange capacities for flourine anion.

Wang Lijun,Li Xiuxi,Zhang Shen,Zhang Chaosheng,

地理学报 , 1994,
Abstract: The contents and partitioning characteristics of rare earth elements (REE) in Wuhan section of the Changjiang River were analysed by neutron activiation analysis (NAA). The contents of solvable fraction of REE in the river was very limited,with the same results as other rivers. On the other hand.the contents of suspended fraction of REE in the river varied in a wide range. It varied with the variation of contents of suspended matter in the water.Contents of REE in the sediments were almost the same with those in the suspended matter. REE were accumulated in fine grained particles,and this showed strong relationship with minerals.The distribution modes showed strong accumulation in the light REE and relatively deficit in Eu. The partitioning charateristics of REE in the sediments and suspended matter were quite similar,With the main amount in residual forms. The amount of five forms obeyed the following order:residual> > bound to organic matter>bound to FeMn oxides> boune to carbonates> > exchangeable. Compared with light and heavy REE, the medium REE(Eu, Sm, Tb) had relatively low percentages in the residual form and high in the forms which are bound to organic matter and Fe-Me oxides. The water bodies of the Wuhan section of the Changjiand River had not been polluted by REE.

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