An efficient, reproducible and rapid fused silica capillary column gas chromatographic method, in splitless mode, for analysing of the three chloroanthracene isomers is described. The method affords efficient separation and good linearity for each isomer in the range of 0.2 -200 μg/ml. The method can also be used in separation and determination of another thirty three aromatic and their halosubstituted compounds. This paper also presents the applications of the method in analysing of complex products mixture from reaction of the selected aromatic compounds with hydrogen chloride on fly ash surface from municipal incinerator. 相似文献
For many clustered populations, the prior information on an initial stratification exists but the exact pattern of the population concentration may not be predicted. Under this situation, the stratified adaptive cluster sampling (SACS) may provide more efficient estimates than the other conventional sampling designs for the estimation of rare and clustered population parameters. For practical interest, we propose a generalized ratio estimator with the single auxiliary variable under the SACS design. The expressions of approximate bias and mean squared error (MSE) for the proposed estimator are derived. Numerical studies are carried out to compare the performances of the proposed generalized estimator over the usual mean and combined ratio estimators under the conventional stratified random sampling (StRS) using a real population of redwood trees in California and generating an artificial population by the Poisson cluster process. Simulation results show that the proposed class of estimators may provide more efficient results than the other estimators considered in this article for the estimation of highly clumped population.
Environmental Science and Pollution Research - Salinity is one of the major causes of abiotic stress that leads to a reduction in crop yield. One strategy to alleviate and improve crop yield is to... 相似文献
Attari Saroba is a village located on the Ferozepur road near Attari Darbar. This study assesses techno-economic feasibility for biogas production in Attari Saroba village using different tools for data collection. Since there was no waste management system in the village, the residents threw household waste in the streets and used the animal waste as the fertilizer, while the leftover waste was disposed off in heaps scattered around the village. This waste can be utilized to generate biogas that can be a renewable substitute for natural gas as natural gas is becoming scarce in our country and is suitable for home use in cooking and heating purposes. Thus, the objective of the study is to combat pollution by managing organic waste and to produce biogas by reusing waste in Attari Saroba through waste recycling process. The suggested type of digester for this area is dispersed growth, Chinese-type combined digester and gasholder. Two designs of different measurements were proposed due to varying family size. The residents were receptive to the idea of installing and maintaining digesters in their homes as they faced regular gas shortages in their area. 相似文献
This study investigates the applicability of multivariate statistical techniques including cluster analysis (CA), discriminant analysis (DA), and factor analysis (FA) for the assessment of seasonal variations in the surface water quality of tropical pastures. The study was carried out in the TPU catchment, Kuala Lumpur, Malaysia. The dataset consisted of 1-year monitoring of 14 parameters at six sampling sites. The CA yielded two groups of similarity between the sampling sites, i.e., less polluted (LP) and moderately polluted (MP) at temporal scale. Fecal coliform (FC), NO3, DO, and pH were significantly related to the stream grouping in the dry season, whereas NH3, BOD, Escherichia coli, and FC were significantly related to the stream grouping in the rainy season. The best predictors for distinguishing clusters in temporal scale were FC, NH3, and E. coli, respectively. FC, E. coli, and BOD with strong positive loadings were introduced as the first varifactors in the dry season which indicates the biological source of variability. EC with a strong positive loading and DO with a strong negative loading were introduced as the first varifactors in the rainy season, which represents the physiochemical source of variability. Multivariate statistical techniques were effective analytical techniques for classification and processing of large datasets of water quality and the identification of major sources of water pollution in tropical pastures. 相似文献
This study aims to determine the composition of surfactants in the lake surface microlayer, rainwater, and atmospheric aerosols
in the area surrounding Lake Chini, Pahang. Surfactants in the lake surface microlayer were taken from seven different stations
around the lake, while samples of rainwater were taken from five different sampling stations. The samples of atmospheric aerosols
were collected from the Lake Chini Research Centre which is in close proximity to the lake. The colorimetric analysis method
was used to determine the composition and concentration of anionic surfactants as methylene blue active substances (MBAS)
and cationic surfactants as disulphine blue active substances (DBAS). The concentration of anionic surfactants, as MBAS, in
the surface microlayer ranged between 0.08 to 0.23 μmol L − 1, while the range of concentration of cationic surfactants as DBAS ranged from 0.09 to 0.11 μmol L − 1. The concentration of MBAS was higher in rainwater when compared to surfactants in the lake surface microlayer. The high
concentration of surfactants in the fine mode of atmospheric aerosols suggests that natural and anthropogenic sources of surfactants
contribute to the atmospheric surfactants. 相似文献
The work describes the physicochemical analysis of the water samples collected from Lahore Canal to evaluate pollution load at different points of the canal. Different physical and chemical pollutants such as temperature, pH, electrical conductivity, total dissolved and suspended solids, turbidity, chlorides, sulphates, nitrates, oils and grease, dissolved oxygen, chemical oxygen demand and biological oxygen demand (BOD) were analysed. The data was analysed through analysis of variance, which showed that the p values for dissolved oxygen (DO), chemical oxygen demand (COD), BOD, electrical conductivity, total dissolved solid (TDS), total suspended solid (TSS), turbidity, oil and grease, sulphates, and nitrates are <0.05, while p value of temperature, pH, and chlorides are 1.000, 0.984, and 0.070, respectively, which are >0.05. Further regression analysis revealed that the simple line regression modal is fit for turbidity and TSS, electrical conductivity and TDS, COD and DO, BOD and DO, and BOD and COD. The studies reveal that Lahore Canal is receiving a considerable amount of physical and chemical pollutants at different points. 相似文献
Journal of Polymers and the Environment - This study investigates the influence of spent coffee (SC), and potassium hydroxide (KOH) modified spent coffee (ACT-SC) as fillers on the mechanical and... 相似文献