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51.
52.
In Iraq, the number of passenger cars, trucks and buses, local generators, and heavy construction equipment rose to a considerable extent since 2003, causing high environmental problems. Many types of pollutants were monitored and recorded for 24 h during March 2016. The study attempts to explore and establish a relationship between the volume of activity and the movement of motor vehicles of various compounds and contaminants resulting from their exhaust pipes, such as sulfur dioxide, particulate matters, oxides of nitrogen, VOCs, and unburned hydrocarbons. The study focused in and around Mohammad Al-Qasim highway adjacent to the University of Technology, Baghdad. The results showed the need for urgent treatments addressed by the environmental authorities in the city. The study results demonstrated that these contaminants are increased during periods of the beginning and end of working hours for government departments. Some types of sulfur compounds (H2S and SO2) concentrations were at serious health-threatening levels, which is a result of the high sulfur content in the Iraqi fuel. The concentrations of NOx and VOC were high, also, which could make the studied area vulnerable to the risk of smog formation. The Iraqi government should make greater efforts to protect the environment and human in this country from the transportation pollution risks.  相似文献   
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This study investigates the energy–growth nexus for transition countries analysing Granger causality between GDP growth per capita and energy use per capita. For this purpose, 17 countries located at Central and Eastern Europe and Caucasian region are chosen and a panel dataset consisting of these countries for the available period of 1990–2011 is studied. In the study, Granger causality is investigated using bootstrapped panel causality approach proposed by Konya (Econ Modell 23(6):978–992, 2006). The approach gives consistent results in case of cross-sectional dependency and heterogeneity of slope coefficients between countries. Causality is examined for two scenarios: one with a trend and one without a trend. The results reveal that, in general, there is no causality running between energy consumption and economic growth, yet there is causality running from energy consumption to economic growth for some countries and sign of the relationship is always negative. Therefore, increases in energy consumption harm economic growth.  相似文献   
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There is an increasing crisis of fresh water availability throughout the world. Sharing the available water resources in a sustainable manner among numerous stakeholders in the backdrop of this crisis is more challenging. Very often water conflicts are triggered out in this challenging scenario. These conflicts are sometimes reconciled with compacts on sharing. Water sharing compacts on both surface and aquifer resources are very common. Whether these compacts are founded on postulates of sustainability is the important question we want to investigate. Conflicts resurface when the sustainability of a compact is at stake. In this paper, we are reviewing three compacts on surface water sharing to understand their sustainability perspectives and how it has helped addressing conflicts. An introduction to various legal instruments promulgated aiming water conflict abatement is given first. Different types of water sharing agreements being signed in the current water management practice are also looked into. Theoretical background of sustainability analysis, both quantitative and qualitative, applicable in the case of water sharing models is then discussed. This is followed by specific case study analysis of three interstate water sharing agreements executed in basins of different agro-climatic regions across the world. It includes the Colorado basin (USA), Murray Darling basin (Australia) and the Parambikulam Aliyar Project (PAP) basins (India). Interstate water sharing agreement of these basins is critically examined and compared to comment on its sustainability perspective. The Murray Darling basin and its compact appear to be better in its overall considerations of sustainability. Compared to Colorado and Murray Darling, PAP requires major revisions in its sustainability context. E flows and stochastic modeling are the thrust areas of PAP that require major revision.  相似文献   
55.
Radon-222 activity concentration has been monitored since 1999 in an underground limestone quarry located in Vincennes, near Paris, France. It is homogeneous in summer, with an average value of 1700 Bq m(-3), and varies from 730 to 1450 Bq m(-3) in winter, indicating natural ventilation with a rate ranging from 0.5 to 2.4 x 10(-6) s(-1) (0.04-0.22 day(-1)). This hypothesis is supported by measurements in the vertical access pit where, in winter, a turbulent air current produces a stable radon profile, smoothly decreasing from 700 Bq m(-3) at 20 m depth to 300 Bq m(-3) at surface. In summer, a thermal stratification is maintained in the pit, but the radon-222 concentration jumps repeatedly between 100 and 2000 Bq m(-3). These jumps are due to atmospheric pressure pumping, which induces ventilation in the quarry at a rate of about 0.1 x 10(-6) s(-1) (0.009 day(-1)). Radon-222 monitoring thus provides a dynamical characterisation of ventilation regimes, which is important for the assessment of the long-term evolution of underground systems.  相似文献   
56.
Food production has to be increased in a sustainable way to meet the future global demand. A key position is attributed to developing countries. A deepened understanding of their agricultural regions with specific resource endowments and constraints is therefore crucial. In this study we propose a methodology based on material flux analysis (MFA) to assess the resource potentials and limitations of a Nicaraguan agricultural region. We focus on current regional and farm resource management and explore them under two scenarios. Indicators are nitrogen and the degrees of self-sufficiency (DSS) for energy, and the staples maize and beans. As data is scarce, most information is based on interviews with farmers of four categories and key persons, and on literature. The results show that nitrogen management does not differ considerably among categories. Nitrogen is mined mostly from staple plots. Self-sufficiency for beans is given in an average year. Yet, landless and small farmers neither produce enough maize for autoconsumption, nor are they self-sufficient for firewood. Energy supply is also the core problem of the region, since the DSS is 70%. Soil nitrogen stocks last at most for three more generations. Analyses with the scenario technique show that: (a) Unlimited population growth has serious consequences in the near future e.g. severe shortage of energy and food. (b) Alternative farming systems are possible, but they require reducing the population by a factor 2, and thus the creation of jobs in a Hinterland. Readers should send their comments on this paper to: BhaskarNath@aol.com within 3 months of publication of this issue.  相似文献   
57.
Environmental Science and Pollution Research - Banana is one of the most important agricultural products of Ecuador. It relies on intensive monoculture cropping systems with a large volume of...  相似文献   
58.

This article shows oily sawdust gasification research on countercurrent installation. Experimental research was on a laboratory scale. The main purpose of the experiment was combustible gas production with higher CH4 concentration. Gas concentrations like CO, CO2, CH4, H2, and CnHm determine syngas composition. The technological parameter’s value defines experimental conditions. Value of this was fuel to air ratio. With fuel to air ratio change, syngas composition was a differential phenomenon where it depended on the process parameters like temperature. Additionally, evaluation of methane formation from CO, H2, and CO2 was done. Methanization coefficients were based on CO and CO2 hydrogenation reactions. Component’s activity was in analogs way to syngas components changed.

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59.
60.
Environmental Science and Pollution Research - Effect-directed analysis (EDA) aims at identifying the compound(s) responsible for toxicity in a complex environmental sample where several dozens of...  相似文献   
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