Environment, Development and Sustainability - In December 2019, WHO was informed with several unknown pneumonia cases and later it was found as highly contagious, transmittable and pathogenic viral... 相似文献
Dry quenching of incandescent coke after it has been pushed from the coking ovens is a proved, reliable process that is presently being used in several industrialized countries. Foremost among dry quenching’s advantages are: (1) virtual elimination of air pollutants emitted during quenching; (2) elimination of potential water pollution associated with wet quenching; (3) improvements in the working environment; (4) saving substantial amounts of energy in usable forms; (5) producing more usable coke that is superior to wet-quenched coke. By continuously circulating inert gases through a cooling chamber that contains hot coke, dry quenching recovers waste-heat energy that can be used to produce steam, to produce electricity, to preheat combustion air, to preheat coal, to dry coal, and to preheat feed water supplied to fuel-fired boilers. The pay-out period on the capital investment (approximately $7,100,000) for an installation capable of processing 5500 tons of coke/day is less than four years. 相似文献
Environmental Science and Pollution Research - Reutilization of putrescible municipal solid wastes (MSW) in agriculture can provide valuable plant nutrients. However, it may pose serious... 相似文献
This paper investigates the impact of CO2 emissions, air pollution (PM2.5) exposure, foreign remittances, energy consumption, renewable energy consumption, trade openness, and gross domestic product per capita on health expenditure in a panel of the 27 highest emitting countries from 2000 to 2019. Focusing on objectives, panel ARDL, and dynamic simulated ARDL models are used to examine the short-run and long-run impact of the variables on health expenditure. An asymmetric or nonlinear ARDL model is used to test the asymmetric effect of CO2 emissions, air pollution exposure, and foreign remittance inflows on health expenditure. The results show that environment-degrading factors, remittances, and GDP per capita significantly impact health expenditure. There is an asymmetric effect of remittances, CO2 emissions, and air pollution (PM2.5) exposure on health expenditure. Based on the results, the study suggests policymakers should make policies regarding environment-degrading elements as these factors cause huge increases in health spending in a country. Consumption of renewable energy helps reduce health expenditure as it does not cause environmental degradation, irrespective of other forms of energy, and it is suggested that policies relating to foreign remittance inflows should be encouraged and made efficient.
Thermodegradation of organometallics viz. RMX (where M = Mg, Ti, Pd, Sn, Si, Al; and X =halogen atom) provides corresponding haloorganics i.e. RX. 1,2‐Shifts of H and Cl on the carbene species like CH2F. CF and CFCL2, CF produced from R. CF. Si F3 (R = CH2F, CFCl2) are preferred to that of fluorine. The thermolysis of R.CF2. Si Cl3 (R = CH2F) produces chloroolefins via halogen exchange. Major products of thermal degradation of poly (vinyl chloride) (PVC) are HCl and benzene but the mechanism of PVC thermodegradation is still a matter of dispute. The thermal cracking of lignins yields substituted phenols. 相似文献
The effects of mercury (HgCl2) on cell population, chlorophyll a concentration and rates of photosynthesis and excretion were investigated in the phytoplanktonic species Dunaliella minuta in laboratory cultures. Mercury, above 25ppb inhibited both cell population and chlorophyll a concentration approximately to the same extent, whereas the photosynthetic rate was inhibited to a significantly lesser degree. Although, the total photosynthetic rate of the tested organism was reduced, above a threshold concentration, the photosynthetic activity was not reduced under these conditions, but it was in fact significantly greater than that in the control culture. This may suggest that in D. minuta the inhibitory effect of mercury is primarily on cell division rather than cellular photosynthesis, which is enhanced by the fact mercury caused a significant increase of the mean cell volume. Mercury, also, decreased the growth rate and final cell yield. The excretory rate was markedly increased at concentrations ≥ 250 ppb of mercury, but at lower concentrations it tended to depend more on the physiological state of cells than on mercury concentration. In the different cultures, the photosynthetic activity showed variations which occurred without major changes in the chlorophyll a content per cell, which remained almost constant and independent of variations in cell size and growth conditions. 相似文献
Environmental Science and Pollution Research - The use of sewage water as an irrigation source can be beneficial in agricultural practices, however, it may result in human health risks due to the... 相似文献
Cameron Highlands is a mountainous region with steep slopes. Gradients exceeding 20∘ are common. The climate is favourable to the cultivation of tea, sub-tropical vegetables and flowers (under rain-shelter).
Crop production is sustained by high fertiliser and manure applications. However, agriculture in this environment is characterised
by high levels of soil erosion and environmental pollution. A study on the sustainability of these agro-ecosystems was conducted.
Results indicated that soil loss was in the range of 24–42 ton/ha/yr under vegetables and 1.3 ton under rain-shelter. Sediment
load in the vegetable sub-catchment reached 3.5 g/L, 50 times higher than that associated with flowers under rain-shelter
and tea. The sediments contained high nutrient loads of up to 470 kg N/ha/yr. The N, P and K lost in runoff from cabbage farms
was 154 kg/season/ha, whereas in chrysanthemum farms it was 5 kg. In cabbage farms, the N, P, and K lost through leaching
was 193 kg/season/ha. The NO3–N concentration in the runoff from the cabbage farms reached 25 ppm but less than 10 ppm in runoff from rain-shelters. Inorganic
pollution in the rivers was within the acceptable limit of 10 ppm. The sustainability of the agro-ecosystems is in the order
of tea { > } rain–shelter ≫ vegetables. 相似文献
Several million people are exposed to fluoride (F?) via drinking water in the world. Current review emphasized the elevated level of fluoride concentrations in the groundwater and associated potential health risk globally with a special focus on Pakistan. Millions of people are deeply dependent on groundwater from different countries of the world encompassing with an elevated level of fluoride. The latest estimates suggest that around 200 million people, from among 25 nations the world over, are under the dreadful fate of fluorosis. India and China, the two most populous countries of the world, are the worst affected. In Pakistan, fluoride data of 29 major cities are reviewed and 34% of the cities show fluoride levels with a mean value greater than 1.5 mg/L where Lahore, Quetta and Tehsil Mailsi are having the maximum values of 23.60, 24.48, > 5.5 mg/L, respectively. In recent years, however, other countries have minimized, even eliminated its use due to health issues. High concentration of fluoride for extended time period causes adverse effects of health such as skin lesions, discoloration, cardiovascular disorders, dental fluorosis and crippling skeletal fluorosis. This review deliberates comprehensive strategy of drinking water quality in the global scenario of fluoride contamination, especially in Pakistan with prominence on major pollutants, mitigation technologies, sources of pollution and ensuing health problems. Considering these verities, health authorities urgently need to establish alternative means of water decontamination in order to prevent associated health problems. 相似文献