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991.
Introduction Nitromusksarewidelyusedassyntheticfragranceingredientsinformulationofsoaps,laundrydetergents,lotions,andbody careproducts,andsoon.Thecommercial anddomesticuseanddischargeofthesecompoundsfrommunicipalsewagesystemshaveledtotheirubiquitousoccurr… 相似文献
992.
The distribution of heavy metals viz., Cd, Co, Cr, Cu, Fe, Mn, Ni, Pb and Zn in the water, sediments, plants and fish samples collected from the Kali Nadi (India) have been determined. The studies have shown that there was considerable variation in the concentration of heavy metals from one sampling station to the other which may be due to the variation in the quality of industrial and sewage wastes being added to the river at different places. The orders of the concentration of heavy metals in water, sediments, plants (Eicchornia crassipes) and fish (Heteropnuestes fossilis) were Fe > Zn > Cu > Mn > Cr > Ni > Pb > Co > Cd; Fe > Zn > Mn > Ni > Cr > Co > Cu > Pb > Cd; Fe > Mn > Zn > Cu > Ni > Co > Pb > Cr > Cd and Fe > Zn > Mn > Ni > Pb > Co > Cr > Cu > Cd, respectively. 相似文献
993.
The implications of a potential ban on shrimp imports by the US from countries that do not utilize the Turtle Excluder Device on commercial shrimp nets is explored in this paper. A Linear Expenditure System (LES) was used to determine the own-price elasticities of demand for shrimp imports. The system of estimated equations was then solved for quantity levels under assumptions made about the trade restrictions, resulting in a set of prices for those import levels. These estimated prices were then used to estimate the compensating variation impact of the trade restrictions. Findings suggest that the environmental regulation would have a negative impact on US consumers, but the magnitude of that effect depends on assumptions made regarding the distribution of US imports after the trade restriction is imposed. 相似文献
994.
Mitigation of climate change impacts on maize productivity in northeast of Iran: a simulation study 总被引:1,自引:0,他引:1
Azam Lashkari Amin Alizadeh Ehsan Eyshi Rezaei Mohammad Bannayan 《Mitigation and Adaptation Strategies for Global Change》2012,17(1):1-16
Development and evaluation of mitigation strategies are fundamental to manage climate change risks. This study was built on
(1) quantifying the response of maize (Zea mays L.) grain yield to potential impacts of climate change and (2) investigating the effectiveness of changing sowing date of
maize as a mitigation option for Khorasan Province which is located in northeast of Iran. Two types of General Circulation
Models (GCM: (United Kingdom Met Office Hadley Center :HadCM3) and (Institute Pierre Simon Laplace: IPCM4)) and three scenarios
(A1B, A2 and B1) at four locations (Mashhad, Birjand, Bojnourd and Sabzevar) employed in this study. Long Ashton Research
Station-Weather Generator (LARS-WG) was employed for generating the future climate. The Cropping System Model (CSM)-CERES-Maize
was used for crop growth simulation under projected climate conditions. The results showed the simulated grain yields of maize
gradually would decrease (from −1% to −39%) during future 100 years compared to baseline under different scenarios and two
GCM at all study locations. The simulation results suggested that delayed sowing date from May to June at all study locations,
except Sabzevar location is the most effective mitigation option for avoiding thermal stress at end of growth period. In addition,
shifting in sowing date to March or April will be beneficial in terms of obtaining higher yields in Sabzevar. Grain yield
did not show special trend from north to south of Khorasan Province in the future climate. In general, change of sowing date
may be quite beneficial to mitigate climate change impacts on grain yield of maize in northeast of Iran. 相似文献
995.
T.F. GoAuthor Vitae D.A. Wahab Author VitaeM.N.Ab. RahmanAuthor Vitae R. RamliAuthor VitaeC.H. AzhariAuthor Vitae 《Journal of Cleaner Production》2011,19(13):1536-1546
Environmental sustainability has become the main items of contest in the automotive industries. Therefore in the order to reduce the environmental impact of end-of-life vehicles, European Union, Japan, USA, and Australia laws require manufacturers to take back their products at the end of their useful life and recycle them. In order to enhance the recycling rate of the vehicle, disassemblability of the automotive components has been a major concern. In the chain of end-of-life, except for landfill and incineration, components of economic value destined for reuse, remanufacture, or recycling have first to be disassembled from the end-of-life vehicles. There are several efforts within the academic community to rationalise design for disassembly and recycling, and several attempts by industry to study these issues in the context of specific products. Recent publications offer a broad perspective on recyclability and disassemblability. It is therefore necessary to determine the optimal stage of disassembly, when all economically valuable components are retrieved. This paper presents a review of several disassemblability methods, including spread sheet-like chart, end-of-life value and time for disassembly. The review concludes on the need for an effective disassembly method in order to enhance the recovery of products. 相似文献
996.
Syed Ali-Musstjab-Akber-Shah Eqani Riffat Naseem Malik Ashiq Mohammad 《Environmental geochemistry and health》2011,33(1):33-47
Organochlorine pesticides (OCPs), viz. β-hexachlorocyclohexane (β-HCH), γ-HCH, aldrin, dieldrin, endrin, heptachlor, endosulfan-I,
endosulfan-II, heptachlor endoepoxide, heptachlor exoepoxide, mirex, dicofol, o,p′-dichlorodiphenyltrichloroethane (o,p′-DDT), p,p′-dichlorodiphenyltrichloroethane (p,p′-DDT), dichlorodiphenyldichloroethane (DDD), and dichlorodiphenyltrichloroethylene (DDE) and 12 other physicochemical parameters
were measured in surface sediments from River Chenab during two sampling seasons (summer and winter, 2007) to evaluate spatial
and temporal trends of sediment pollution. Hierarchical agglomerative cluster analysis identified three groups of sites based
on spatial similarities in physicochemical parameters and OCP residual concentrations. Spatial discriminant function analysis
(DFA) segregated 14 parameters, viz. dicofol, endosulfan-I, heptachlor endoepoxide, dieldrin, DDD, DDE, endosulfan-II, o,p′-DDT, p,p′-DDT, pH, electrical conductivity (EC), Cl−1, total P (%), and silt, which explained 96% of total variance between spatial groups. γ-HCH was the most frequently detected
(63%) pesticide, followed by DDD (56%). The ratio of DDTs to their metabolites indicated current input and anaerobic biodegradation.
Temporal DFA highlighted aldrin, heptachlor endoepoxide, Cl−1, total P, and EC as important variables which caused variations between summer and winter. DDTs were relatively more prevalent
as compared to other OCPs in the sediments samples during both seasons. DDT metabolites were detected at greater frequencies
and concentrations in winter, whereas DDT isomers were more prevalent in summer sediment samples. Factor analysis identified
agricultural and industrial activities as major sources of sediment OCP contamination. Concentrations of γ-HCH, heptachlor
endoepoxide, dieldrin, and DDTs (isomers and metabolites) in all sediment samples were well above interim sediment quality
guidelines (ISQGs) and probable effect limits (PEL) given by Canadian Sediment Quality Guidelines (CSQGs). 相似文献
997.
Mohammad Sadegh Taskhiri Anthony S.F. Chiu 《Resources, Conservation and Recycling》2011,55(7):730-737
The establishment of an eco-industrial park (EIP) provides opportunity for individual plants to cooperate with each other in order to utilize resources efficiently and thus reduce waste. The goal of an EIP is to “close the loop” through recycling and reuse of material and energy streams. Studies show with current freshwater consumption trends there would be water stress aggravated by global warming in the near future. This paper presents a model to design an EIP water reuse network that considers overall system sustainability as measured with emergy, as well as cost saving desired by individual plants. Case studies from literature are then solved to illustrate the advantage of this method in decision making. The illustrative examples show how the model achieves a compromise among the potentially conflicting fuzzy goals of the various EIP stakeholders. 相似文献
998.
In this paper, we consider design-based estimation using ranked set sampling (RSS) in finite populations. We first derive
the first and second-order inclusion probabilities for an RSS design and present two Horvitz–Thompson type estimators using
these inclusion probabilities. We also develop an alternate Hansen–Hurwitz type estimator and investigate its properties.
In particular, we show that this alternate estimator always outperforms the usual Hansen–Hurwitz type estimator in the simple
random sampling with replacement design with comparable sample size. We also develop formulae for ratio estimator for all
three developed estimators. The theoretical results are augmented by numerical and simulation studies as well as a case study
using a well known data set. These show that RSS design can yield a substantial improvement in efficiency over the usual simple
random sampling design in finite populations. 相似文献
999.
Mohammad Dadashzadeh Faisal Khan Kelly Hawboldt Rouzbeh Abbassi 《Process Safety and Environmental Protection》2011,89(5):295-299
Fugitive emission rate quantification in an oil and gas facility is an important step of risk management. There are several studies conducted by the United States Environmental Protection Agency (USEPA) and American Petroleum Institute (API) proposing methods of estimating emission rates and factors. Four major approaches of estimating these emissions, in the order of their accuracy, are: average emission factor approach, screening ranges emission factor approach, USEPA correlation equation approach, and unit-specific correlation equation approach. The focus of this study is to optimize the USEPA correlation equations to estimate the emission rate of different units in an oil and gas facility. In the developed methodology, the data available from USEPA (1995) is used to develop new sets of equations. A comparison between USEPA correlation equations and the proposed equations is performed to define the optimum sets of equations. It is observed that for pumps, flanges, open-ended lines, and others, the proposed developed equations provide a better estimation of emission rate, whereas for other sources, USEPA equations supply the better estimate of emission rate. 相似文献
1000.