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971.
Environmental Science and Pollution Research - The study inspects the inverted U shape of the environmental Kuznets curve (EKC) hypothesis following the influence of economic growth on CO2...  相似文献   
972.
Environmental Science and Pollution Research - Exposure to light at night, pineal gland impairment, and the environmental pollutant trichloroethylene (TCE) have serious implications for health and...  相似文献   
973.

Rising economic growth in recent ages is the primary concern of most of the countries to enhance the living standard, but the ever-increasing production of economic activities consumes a lot of energy, which leads to a sharp increase in carbon dioxide emissions. Innovation may be a remedy that can help improve energy efficiency, obtain renewable energy, and promote economic growth, thereby protecting the quality of the environment. Therefore, this paper examines the role of innovation and renewable energy consumption in CO2 reduction in OECD countries from 2004 to 2019. By using the two-step system generalized of moment estimator, the results show that economic growth and innovation significantly increase carbon emissions, however the innovation Claudia Curve (ICC) is verified, and the environmental Kuznets curve does not exist. Foreign direct investment has a negative impact on carbon emissions, thus verifying the Pollution Hao hypothesis, whereas renewable energy also improves environmental quality, but the interaction between innovation and renewable energy consumption still increases carbon emissions. Financial development, industrialization, trade, and energy consumption have also been found to be harmful factors of environmental quality. Our findings have considerable policy implications for OECD countries on the improvement of innovation indicators and investment in renewable energy sources to rise environmental quality.

  相似文献   
974.
Environmental Science and Pollution Research - Oilfield-produced wastewater (OPW) provided by the local oil industry was used as a medium (without any pre-treatment) for the outdoor cultivation of...  相似文献   
975.
Different land uses in subtropics play an important role in regulating the global environmental changes. To reduce uncertainties of greenhouse gas (GHG) emissions of agricultural soils in subtropical ecosystem, a four years campaign was started to determine the temporal GHG (CO2 and CH4) fluxes from seven sites of four land use types (1 vegetable field, 3 uplands, 2 orchards, 1 pine forest). The mean annual budgets of CO2, and CH4 were 6.5~10.5 Mg CO2 ha?1 yr?1, and +0.47 ~ ?2.37 kg CH4 ha?1 yr?1, respectively. Pine forest had significantly lower CO2 emission and higher CH4 uptake than agriculture land uses. Tilled orchard emitted more CO2 and oxidized less CH4 than non-tilled orchard. Upland crops had higher CO2 emissions than orchards, while abrupt differences of CH4 uptake were observed between upland crops and orchards. Every year, the climate was warm and wet from April to September (the hot–humid season) and became cool and dry from October to March (the cool–dry season). Driven by seasonality of temperature and WFPS, CO2 fluxes were significantly higher in the hot–humid season than in cool–dry season. Soil temperature, WFPS, NO3?–N and NH4+–N contents interactively explained CH4 uptake which was significantly higher in cool–dry season than in hot–humid season. We conclude that soil C fluxes from different land uses are strongly under control of different climatic predictors along with soil nutrient status, which interact in conjunction with each other to supply the readily available substrates.  相似文献   
976.
977.
The present study was undertaken to evaluate a nested polymerase chain reaction (PCR) for detection of Y chromosome-specific fetal DNA in maternal plasma and urine of pregnant women during different gestational stages. DNA isolated from plasma and urine samples of 80 pregnant women (between 7 and 40 weeks' gestation) underwent amplification for Y chromosome-specific 198 bp DNA by nested PCR. The postpartum analysis of fetal gender showed that 55 women carried male and 25 female fetuses. Among the 55 women bearing male fetuses, Y chromosome-specific signals were detected in 53 (96%) plasma and 21 (38%) urine samples. Moreover, out of 25 women bearing female fetuses, 3 (12%) and 1 (4%) women had Y chromosome-specific signal in plasma and urine, respectively. Analysis of results with respect to gestational age revealed that there was no significant difference in the detection of Y chromosome-specific DNA between different trimesters in maternal plasma of women bearing male fetuses. These results showed that fetus-specific DNA was detected with high sensitivity (96%) and specificity (88%) in the maternal plasma by nested PCR, and therefore the method could be useful as a non-invasive procedure for fetal sex determination and prenatal diagnosis. Copyright © 2001 John Wiley & Sons, Ltd.  相似文献   
978.
There is a need to assess climate change mitigation opportunities in forest sector in India in the context of methodological issues such as additionality, permanence, leakage and baseline development in formulating forestry mitigation projects. A case study of forestry mitigation project in semi-arid community grazing lands and farmlands in Kolar district of Karnataka, was undertaken with regard to baseline and project scenario development, estimation of carbon stock change in the project, leakage estimation and assessment of cost-effectiveness of mitigation projects. Further, the transaction costs to develop project, and environmental and socio-economic impact of mitigation project was assessed. The study shows the feasibility of establishing baselines and project C-stock changes. Since the area has low or insignificant biomass, leakage is not an issue. The overall mitigation potential in Kolar for a total area of 14,000 ha under various mitigation options is 278,380 t C at a rate of 20 t C/ha for the period 2005–2035, which is approximately 0.67 t C/ha/year inclusive of harvest regimes under short rotation and long rotation mitigation options. The transaction cost for baseline establishment is less than a rupee/t C and for project scenario development is about Rs. 1.5–3.75/t C. The project enhances biodiversity and the socio-economic impact is also significant.
N. H. RavindranathEmail:
  相似文献   
979.
980.
This work is dedicated to the removal of free cyanide from aqueous solution by oxidation with hydrogen peroxide H2O2 catalyzed by neutral activated alumina. Effects of initial molar ratio [H2O2]0/[CN?]0, catalyst amount, pH, and temperature on cyanide removal have been examined. The presence of activated alumina has increased the reaction rate showing thus, a catalytic activity. The rate of removal of cyanides increases with rising initial molar ratio [H2O2]0/[CN?]0 but decreases at pH 10 to 12. Increasing the alumina amount from 1.0 to 30 g/L has a beneficial effect, and increasing the temperature from 20 °C to 35 °C improves cyanide removal. The kinetics of cyanide removal has been found to be of pseudo-first-order with respect to cyanide and the rate constants have been determined.  相似文献   
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