A laboratory modelling for the assessment of damage to marble by the SO2-acidity in the vicinity of stacks has been devised. The modelling is based on the role of metal oxide particulates (also emitted by smoke-stacks) which catalytically convert SO2 to SO3 forming H2SO4 (in presence of water), which has an excessively high selectivity, compared with HNO3, for corroding marble. The requisites of the modelling are: (1) determination of composition of the marble, (2) immersion of samples of marble blocks (after measurement of surface areas) in H2SO4 solutions of known concentrations, maintaining pH and temperature at their initial values, (3) determination of concentrations of Ca and Mg (major components of marble) in the leachate, and thereby evaluating the mass loss of the marble, in terms of mg marble cm–2 day–1, for each level of H2S04 concentration, (4) application of derived data for evaluation of duration (in years) for the decay of 1 cm thickness of marble block by the process of surface corrosion. From the modelling, it was found that the duration for the damage of 1 cm thickness of the marble sample used here by SO2 acidities of 1, 5, 10, 50 and 100 ppm are 83.01, 69.02, 31.24, 8.19 and 4.31 years respectively. 相似文献
The present study aimed to elucidate the remediation potential of visibly dominant, naturally growing plants obtained from an early colonized fly ash dump near a coal-based thermal power station. The vegetation comprised of grasses like Saccharum spontaneum L., Cynodon dactylon (L.) Pers., herbs such as Tephrosia purpurea (L.) Pers., Sida rhombifolia L., Dysphania ambrosioides (L.) Mosyakin & Clemants, Chromolaena odorata (L.) King & H.E. Robins along with tree saplings Butea monosperma (Lam.) Taub. The growth of the vegetation improved the N and P content of the ash. Average metal concentrations (mg kg?1) in the ash samples and plants were in order Mn (345.1)?>?Zn (63.7)?>?Ni (29.3)?>?Cu (16.8)?>?Cr (9.9)?>?Pb (1.7)?>?Cd (0.41) and Cr (58.58)?>?Zn (52.74)?>?Mn (39.09)?>?Cu (10.71)?>?Ni (7.45)?>?Pb (5.52)?>?Cd (0.14), respectively. The plants showed fly ash dump phytostabilization potential and accumulated Cr (80.19–178.11 mg kg?1) above maximum allowable concentrations for plant tissues. Positive correlations were also obtained for metal concentration in plant roots versus fly ash. Saccharum spontaneum showed highest biomass and is the most efficient plant which can be used for the restoration of ash dumps.
Environmental Chemistry Letters - Water contamination by emerging contaminants is increasing in the context of rising urbanization, industrialization, and agriculture production. Emerging... 相似文献
Climate change vulnerability depends upon various factors and differs between places, sectors and communities. People in developing countries whose subsistence livelihood depends mainly upon agriculture and livestock production are identified as particularly vulnerable. Nepal, where the majority of people are in a mixed agro-livestock system, is identified as the world’s fourth most vulnerable country to climate change. However, there is limited knowledge on how vulnerable mixed agro-livestock smallholders are and how their vulnerability differs across different ecological regions in Nepal. This study aims to test two vulnerability assessment indices, livelihood vulnerability index and IPCC vulnerability index, around the Gandaki River Basin of central Nepal. A total of 543 households practicing mixed agro-livestock were surveyed from three districts, namely Dhading, Syangja and Kapilvastu representing three major ecological zones: mountain, mid-hill and Terai (lowland). Data on socio-demographics, livelihood determinants, social networks, health, food and water security, natural disasters and climate variability were collected and combined into the indices. Both indices differed for mixed agro-livestock smallholders across the three districts, with Dhading scoring as the most vulnerable and Syangja the least. Substantial variation across the districts was observed in components, sub-components and three dimensions (exposure, sensitivity and adaptive capacity) of vulnerability. The findings help in designing site-specific intervention strategies to reduce vulnerability of mixed agro-livestock smallholders to climate change. 相似文献
Environmental Science and Pollution Research - Research on phase change material (PCM) for thermal energy storage is playing a significant role in energy management industry. However, some hurdles... 相似文献
Environmental Science and Pollution Research - Increasing petroleum consumption and a rise in incidental oil spillages have become global concerns owing to their aquatic and terrestrial toxicity.... 相似文献
Environmental Science and Pollution Research - Climate change and global warming are the visible consequences of the increased amount of carbon dioxide (CO2) in the atmosphere. Among the various... 相似文献
Effect of cumulative doses of estradiol -17beta (E2-7, 14 and 28 mg/kg body weight) and 17alpha, 20beta-dihydroxy-4-pregnen-3-one (17alpha,20betaP-7, 14 and 28 mg/kg body weight) on total phospholipids (TP) and various phospholipids- phosphatidylcholine (PC), phosphatidylserine (PS), phosphatidylinositol (PI) and phosphatidylethanolamine (PE) on liver plasma and ovary were investigated during the reproductively active preparatory and prespawning phases of the annual reproductive cycle in the freshwater female catfish, H. fossilis. The effect of E2 on TP was generally stimulatory and has pronounced effect than 17alpha,20betaP during both the phases. The levels of PC was promoted high during prespawning phase by E2 comparatively very less than by 17alpha, 20betaP in studied tissues during both the phases. The levels of PS after E2 treatments was maximum in all tissues during prespawning phase whereas 17alpha,20betaP was effective only in liver during this phase. The PI was elevated in liver during preparatory phase but its elevation was in all studied tissues during prespawning phase after E2 treatments. The levels of PI was most effective in ovary during preparatory phase in response to 17alpha,20betaP. The levels of PE was declined in liver but elevated in ovary after E2 treatments during both the phases. Treatments of E2 during preparatory phase showed greater number of vitellogenic oocytes as compared to 17alpha,20betaP treatments. The present finding has demonstrated that estradiol-17beta has more pronounced effects than the 17alpha,20beta P in regulation of different phospholipids and ovarian recrudescence during reproductively active phases and among the phospholipids the PC is the main phospholipids of vitellogenin/ovarian lipids in H. fossilis. 相似文献
Few other policy zones are as complex as the issue of climate change. If the more pessimistic projections of climate change doom are correct, then the failure to address the issue is likely to be catastrophic and irreversible. The Inter-governmental Panel on Climate Change has predicted the potential extinction of many species and that the existence of small-island and other vulnerable countries will be threatened if business-as-usual greenhouse gas emissions continue. Climate change is a transboundary problem and requires unprecedented levels of cooperation between states and serious and sustained responses from major emitters. However, the growing demand and consumption of natural resources for continued energy security and cornucopian economic growth have undermined the outcomes of international climate change negotiations. It is argued here that there is a strong connection between the major emitters’ positions at United Nations’ climate talks, their possessions, dependence and consumption of natural resources, and the continued undermining of international climate change policy for unsustainable growth. This paper assesses the resource politics of the US, China, India, Canada, Russia, and Saudi Arabia and their positions at climate talks to show the link between lack of climate change policy progress and the positions of these main players. 相似文献