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101.
ZHENG Xilai WANG Bingchen LI Yuying XIA Wenxiang Institute of Environmental Science Engineering Ocean University of Chin Qingdao Shandong Comprehensive Institute of Geotechnical Survey Beijing 《《地质学报》英文版》2004,78(3)
On the basis of site investigation and sample collection of petroleum contaminants in the soil-water-crop system in the Shenyang-Fushun sewage irrigation area, the physical-chemical-biological compositions of the unsaturated zone is analyzed systematically in this paper. At the same time, the degradation kinetics of residual and aqueous oils is determined through biodegradation tests. The studies show that dominant microorganisms have been formed in the soils after long-term sewage irrigation. The microorganisms mainly include bacteria, and a few of fungus and actinomycetes. After a 110-days' biodegradation test, the degradation rate of residual oil is 9.74%-10.63%, while the degradation rate of aqueous oil reaches 62.43%. This indicates that the degradation rate of low-carbon aqueous oil 相似文献
102.
Wu Huiding Yang Xuelian Bai Shan Li Guoqing . National Marine Environmental Forecasting Centre State Oceanic Administration Beijing China . Department of Physics Physical Oceanography Memorial University of Newfoundland St. John' s 《海洋学报(英文版)》1999,(2)
INTRODUCTIONIt is well-known that a typhoon has a strong wind zone and very steep pressure gradient. Thespatial and temPOral variations of the meteorological quantities within a typhoon are much largerthan that in a common synOPtic system and it involves strong convective activities. The details ofthe structures and physical processes of typhoons need to be properly resolved when we do the numerical simulation. When designing a typhoon model, however, the effect of large scale synopticsy… 相似文献
103.
Abstract factor analyses were performed on databases consisting of simulated samples from aqueousequilbria.The program COMPLEX was used to generate equilibrium species in a system of three reactantmetals and five reactant bases.Reactant concentrations and pH were drawn from random-normaldistributions so that sample data vectors comprised a multivariate log-normal distribution of equilibriumconcentrations.In addition,sample groups were created containing different distributions for pH andreactant concentrations.Equilibrium species were shown to contain variance contributed by change in pH among samples aswell as change in reactant concentrations.Factor modelling revealed the qualitative relationships amongthe species and how the relationships change with pH.Factors also revealed those reactants containingvariance in the data matrix.In some cases,reactant variance obscured relationships between pH and theequilibrium species.Since factor modelling of a simulated data matrix revealed the expected chemical equilibriuminteractions,a potentially powerful tool exists for investigating the effects of outliers and error. 相似文献
104.
105.
HOU Jianjun LAI Hongyan HUANG Bangqin CHEN Jixin College of Fisheries Huazhong Agricultural University Wuhan China College of Life Sciences Hubei Normal University Huangshi China State Key Laboratory of Marine Environmental Science Environmental Science Research Center Xiamen University Xiamen China Key Laboratory of Freshwater Fish Germplasm Resources Biotechnology Yangtse River Fisheries Research Institute Jinzhou China State Key La... 《海洋学报(英文版)》2009,28(2)
Partial rDNA sequences of Prorocentrum minimum and Takayama pulchella were amplified, cloned and sequenced, and these sequence data were deposited in the GenBank. Eight oligonucleotide probes (DNA probes) were designed based on the sequence analysis. The probes were employed to detect and identify P. minimum and T. pulchella in unialgal and mixed algal samples with a fluorescence in situ hybridization method using flow cytometry. Epifluorescence micrographs showed that these specific probes labeled with flu... 相似文献
106.
Different attenuation correction methods for the X-band dual linear polarimetric radar are analyzed in this paper.The specific differential phase shift K DP is always considered as an effective factor in radar signal attenuation correction.However,the values of K DP for light rains are too small,which results in unstable quality and large errors of rainfall estimation.Therefore,radar horizontal reflectivity Z H and specific differential phase shift are combined together in the Z H –K DP method to correct th... 相似文献
107.
Ground-based measurements are essential for understanding alpine glacier dynamics,especially in remote regions where in-situ measurements are extremely limited.Prom 1 May to 22 July 2005(the spring-summer period),and from 2 October 2007 to 20 January 2008(the autumn-winter period),surface radiation as well as meteorological variables were measured over the accumulation zone on the East Rongbuk Glacier of Mt. Qomolangma/Everest at an elevation of 6560 m a.s.l.by using an automatic weather station(AWS).The... 相似文献
108.
BAI Liping WANG Yeyao SUN Jiali GONG Bin .College of Water Sciences Beijing Normal University Beijing China .Chinese Research Academy of Environmental Sciences Beijing China 《东北亚地学研究》2009,12(1):40-45,56
The occurrence of debris flow is affected by many factors. Risk zoning of debris flow plays a vital role in the early-warning and prediction of abrupt geological hazards, and exploration of new method is needed in the early-warning and prediction of geological hazards. The extension theory is a new method to solve contradiction matters. Based on extension theory, AHP and GIS, the risk zoning model of debris flow was established in this paper. The result of this research provides a new way in the risk zoning, early-warning and prediction of debris flow 相似文献
109.
Alpine glaciers usually feature with best hydrothermal condition in mountain climate,and present beautiful glacier scenery,various glacier landforms,rich biodiversity,and easier accessibility,compared with continental glaciers or ice sheets.Nevertheless,Alpine glaciers are more sensitive to climate warming,and climate warming has seriously affected Alpine glaciers and surroundingenvironment.The quality and attractiveness of Alpine glaciers to tourism has been and will continue to be diminished with tourists... 相似文献
110.
In order to verify the feasibility and stability of a degree-day model on simulating the long time series of glacier mass balance, we apply a degree-day model to simulate the mass balance of Urumqi Glacier No. 1 for the period 1987/1988-2007/2008 based on temperature and precipitation data from a nearby climate station. The model is calibrated by simulating point measurements of mass bal-ance, mass balance profiles, and mean specific mass balance during 1987/1988-1996/1997. The opti-mized parameters are obt... 相似文献