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101.
Particulate matter concentrations were measured in an industrial region in the Ganjam district of Odisha. The average levels of suspended particulate matter (SPM) were measured to be 142 ± 8 and PM10 of particulate matter with a size of less than 10 micrometers (PM10) to be 50 ± 15 μg m?3. Out of the 14 elements determined, Ca, Na, Mg, Fe, and K contributed more than 95% of the total weight. In enrichment factors, the trace elements, i.e., Zn, Pb, Cd, and Hg were observed to be highly enriched in the SPM and PM10. Factor analysis indicates that more than 75% of the variance was due to five component factors, which have eigenvalues greater than 1. Intake of elements through inhalation route to adults has been estimated.  相似文献   
102.
Effects of BHC (8 mg litre(-1)) and malathion (10 mg litre(-1)) exposure for 96 h have been studied on T(3) and T(4) concentrations in plasma, and in pharyngeal thyroid tissue preparations. Thyroid peroxidase (TPO) activity in the pharyngeal thyroid tissue, along with the extra-thyroidal conversion of T(4) into T(3) were measured in a freshwater catfish, Heteropneustes fossilis. BHC stimulated TPO activity in this fish, during both in vitro and in vivo studies. In contrast, malathion was found to stimulate TPO activity during the in vitro experiments but to inhibit it in the in vivo study. Concentrations of T(3) and T(4) increased in the thyroid gland, as well as in the plasma, in response to BHC exposure. However, in both these tissues, malathion increased T(3) concentrations and reduced T(4) concentrations. The extrathyroidal conversion of T(4) into T(3) was stimulated by malathion and inhibited by BHC.  相似文献   
103.
Examining the contribution of fossil fuel CO2to the total CO2changes in the atmosphere is of primary concern due to its alarming levels of fossil fuel emissions over the globe,specifi cally developing countries.Atmospheric radiocarbon represents an important observationa constraint and utilized to trace fossil fuel derived CO2(CO2ff) in the atmosphere.For the firs time,we have presented a detailed analysis on the spatial distribution of fossil fuel der...  相似文献   
104.
Dissipation behaviour of ready mix polytrin C 44EC (profenophos 40% + cypermethrin 4%) and spark 36EC (triazophos 35%+.deltamethrin 1%) applied at 1 L/ha in okra crop during Kharif in year 2000 was studied at 0, 1, 3, 5 and 7 days after treatment. Dissipation on 7th day was found to be maximum (98.4%) for profenophos followed by triazophos (86.2%), cypermethrin (73.5%) and deltamethrin (55.7%). Half life (t1/2) values for the above insecticides were 1.35, 2.55, 4.11 and 7.60 days, respectively. All the insecticides followed a first order kinetics. Profenophos and triazophos followed a biphasic dissipation pattern with faster dissipation in phase I (0–1 days) and manifesting slower rate of dissipation in phase II (1–7 days).  相似文献   
105.
Environmental Chemistry Letters - The rising energy conflicts and environmental pollution are calling for the rapid development of advanced techniques such as photoelectrocatalysis to...  相似文献   
106.
The proper disposal of discarded waste tires is becoming a serious matter of concern worldwide as huge proportion of this waste is being generated which makes the proper disposal virtually infeasible. About 1000 million of waste tires are discarded every year, and by the year 2030, it will turn up to 1200 million per year. If this enormous quantum of waste remains unattended, it would led to serious health and environmental problems. The investigation aims at appraising the compaction and strength characteristics of clayey soil incorporated with waste crumb rubber and cement for its sustainable use in geotechnical application. A series of unconfined compression strength and split tensile strength tests were carried out on clayey soil incorporated with two percentages of cement (3 and 6%) by weight and four percentages of crumb rubber (2.5, 5.0, 7.5, and 10.0%) by weight. Moreover, scanning electron microscope analysis was also carried out to get better intuition about the behaviour of the composite. Test results suggested that crumb rubber (up to 5%) could be mixed with uncemented/cemented clay soil with the congruent impression. The inclusion of discarded waste tires in cemented clay would be one of the congenial methods for the disposal of this waste as it substantially reduces the deleterious influence of waste tire disposal on human health and ecology.  相似文献   
107.
Today, environment pollution control is a matter of concern, everybody is willing to make a product that should be ecofriendly. Nowadays, water resources are full of untreated waste materials, discharge of hazardous and toxic dyes coming from textile and other chemical industries. These environmental hazards are difficult to remove by commercial water treatment plans, thus we need something that would present an efficient means for removal of these hazards. In this research paper, we have synthesize silver nanoparticle in a green way by using aqueous extract of Allium cepa (onion), and further these silver nanoparticle were tested for the catalytic degradation of various dyes by UV/Visible spectroscopy and silver nanoparticle showed reduction in dyes intensity after a particular period of incubation time. SEM and TEM, Particle size and Zeta potential analysis was done to analyze the surface morphology, particle size range and stability of the silver nanoparticle. Greenly synthesized silver nanoparticle was found to be spherical in shape, having particle size value ranged from 50 to 100 nm with a zeta potential value of ?29 mV. An EDX spectroscopy method was used to confirm the presence of silver nanoparticle in the synthesized material. An X-ray crystallography was done to ensure the crystallinity of the silver nanoparticle. Further an ATR-FTIR was performed to confirm the capping of the silver nanoparticle with the phenolic group of the onion. All these study emphasized that silver nanoparticle capped with onion (AgNPs@Ac) is the excellent catalyst for the reduction of hazardous and toxic dyes as well as they serve best purpose of the eco-friendly approach.  相似文献   
108.
Environmental Science and Pollution Research - Reversible hydrogen storage in MgH2 under specified conditions is a possible way for the positive reception of hydrogen economy, in which the...  相似文献   
109.
Illicit trade in wildlife products is rapidly decimating many species across the globe. Such trade is often underestimated for wide‐ranging species until it is too late for the survival of their remaining populations. Policing this trade could be vastly improved if one could reliably determine geographic origins of illegal wildlife products and identify areas where greater enforcement is needed. Using DNA‐based assignment tests (i.e., samples are assigned to geographic locations), we addressed these factors for leopards (Panthera pardus) on the Indian subcontinent. We created geography‐specific allele frequencies from a genetic reference database of 173 leopards across India to infer geographic origins of DNA samples from 40 seized leopard skins. Sensitivity analyses of samples of known geographic origins and assignments of seized skins demonstrated robust assignments for Indian leopards. We found that confiscated pelts seized in small numbers were not necessarily from local leopards. The geographic footprint of large seizures appeared to be bigger than the cumulative footprint of several smaller seizures, indicating widespread leopard poaching across the subcontinent. Our seized samples had male‐biased sex ratios, especially the large seizures. From multiple seized sample assignments, we identified central India as a poaching hotspot for leopards. The techniques we applied can be used to identify origins of seized illegal wildlife products and trade routes at the subcontinent scale and beyond.  相似文献   
110.
The present study was performed to investigate the performance of activated carbon-supported copper and manganese base catalyst for catalytic wet oxidation (CWO) of pulping effluent. CWO reaction was performed in a high pressure reactor (capacity?=?0.7 l) at temperatures ranging from 120 to 190 °C and oxygen partial pressures of 0.5 to 0.9 MPa with the catalyst concentration of 3 g/l for 3 h duration. With Cu/Mn/AC catalyst at 190 °C temperature and 0.9 MPa oxygen partial pressures, the maximum chemical oxygen demand (COD), total organic carbon (TOC), lignin, and color removals of 73, 71, 86, and 85 %, respectively, were achieved compared to only 52, 51, 53, and 54 % removals during the non-catalytic process. Biodegradability (in terms of 5-day biochemical oxygen demand (BOD5) to COD ratio) of the pulping effluent was improved to 0.38 from an initial value of 0.16 after the catalytic reaction. The adsorbed carbonaceous fraction on the used catalyst was also determined which contributed meager TOC reduction of 3–4 %. The leaching test showed dissolution of the metals (i.e., Cu and Mn) from the catalysts in the wastewater during CWO reaction at 190 °C temperature and 0.9 MPa oxygen partial pressures. In the future, the investigations should focus on the catalyst reusability.  相似文献   
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