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121.
Photolysis (254 nm, 72h) of 1-nitro-2-phenylnaphthalene 1 in methanol gave 2-phenyl-1,4-naphthoquinone-4-monoxime 2, 2,2′-diphenyl-4,4′-binaphth-1,1′-diol 3 and 2,2′-diphenyl-4,4′-binaphth-1,1′-dione 4. Straightforward reactions available to the environment account for the formation of the products: (a) isomerisation of the nitro compound into a nitrite ester followed by either (a) migration of the nitroso group and isomerisation into the oxime 2 or (b) oxidative coupling and solvolysis into the binaphthol 3 and followed by oxidation into the binaphthone 4.  相似文献   
122.
This paper documents the variation in pressure drop and collection efficiency for fiberglass/fly ash fabric filter systems caused by variations in cleaning intensity (reverse air and reverse pulse), air to cloth ratio, and dust loading. Reverse air rates greater than 2 fpm were required to produce stable pressure characteristics. Pulse jet pressure greater than 50 psi reduced collection efficiency. Increased air to cloth ratios produced decreased collection efficiency.  相似文献   
123.
This paper investigates a techno-economic analysis on small and medium scales: 50 kilo tonnes per annum (ktpa) and 100 ktpa combustion plants with steam turbine technology utilising solid recovered fuel (SRF). Energy and efficiency calculations for the technical assessment are performed. The economic viability of the two processes is investigated through a discounted cash flow analysis. The levelised cost is used to calculate the cost of production of one unit of electricity. A life cycle assessment (LCA) of the 100 ktpa scale SRF plant is performed, where the foundations of LCA calculations reside in energy calculations carried out for the technical analysis. Life cycle inventories were developed using inventory analysis and impact assessment. The results of the LCA are compared with those from equivalent scale coal, natural gas and electricity-mix plants. The LCA is also compared with a landfill reference system. Both scales are economically and technically viable. The SRF plant has a lower global warming potential emission (EGWP) compared with the coal, natural gas and electricity-mix plants and the reference landfill system.  相似文献   
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125.
Fluoride Deposition in Central India   总被引:1,自引:0,他引:1  
Fluoride is a volatile element emitted from natural and anthropogenic sources into the atmoshere and scavenged from the atmosphere by rain water. We collected 444 rain water and 36 dust samples on an event basis at 13 sites and on the bulk basis (monthly) at 3 sites, respectively, in central India (extending over 17°N to 24°N latitude and 80° 17 to 84°11E longitude). The level of F- in the atmospheric samples was determined by automating the conventional Zr(IV)-SPADNS [Sodium 2- (parasulfophenylazo)-1, 8-dihydroxy-3, 6-naphthalene disulfonate] method in the presence of surfactant, i.e. TX–100 [Triton x- 100]. The detection limit of the method is 10.0 ppb F- with a sample throughput of 70 samples/h. The F- deposited with rain water (in 13 sites) and with dust (three sites) were ranged between 54.8 to 483.0, and 105.0 to 503.3 kg/km2/year, respectively. The level of F- in atmospheric samples, seasonal and spatial variation in deposition and sources of F- are discussed.  相似文献   
126.
B. Patel  K. Anthony 《Marine Biology》1991,108(3):457-470
The effect of cadmium introduced as inorganic salts (chloride, nitrate, sulfate, carbonate, acetate and iodide) or organic chelates (with EDTA, NTA and humic acid) on the physiological behaviour of six species of tropical lamellibranchs — arcid blood clamsAnadara granosa andA. rhombea, venerid clamsMeretrix casta andKatelysia opima, and mytilid musselsPerna viridis andP. indica, collected from various intertidal areas in southern India from 1986 to 1989 — was evaluated. Inorganic salts of Cd are reported to completely ionize upon introduction to full-strength sea water and form predominantly (97%) chloride complexes. Some inorganic Cd salts, therefore, would hardly affect physiological parameters. However, bioaccumulation of Cd was greatest upon exposure to Cd introduced as sulfate, followed by iodide, acetate, chloride, nitrate and carbonate; 96-h LC50's also varied, but in a different order, being highest for chloride (3.5µg ml–1), followed by nitrate, acetate, iodide and sulfate (1.8µg ml–1). Furthermore, Cd levels increased linearly with time of exposure and levels in medium, and were species-specific, being highest in the arcid clams, followed by the venerid clams and mytilid mussels. The presence of other metals such as Zn reduced bioaccumulation of Cd significantly (P < 0.001), but the reverse was not true. Upon exposure to Cd in the presence of Cu, on the other hand, accumulation of both metals was reduced by 15 to 20%. In the presence of organic chelators — EDTA, NTA and reduced glutathione (GSH) — Cd accumulation was significantly inhibited, by 1/2 to 1/3. Humic acid, on the other hand, had no effect. Cd levels in soft tissues were inversely related to ambient salinity in the range of 12 to 32. However, both Zn and Cu significantly inhibited Cd accumulation irrespective of salinity. Cd increased the rate of filtration inAnadara granosa over the first 24 h by 28%, but on prolonged exposure (96 h) that rate decreased significantly, by 50%. Zn alone and in the presence of Cd, on the contrary, initially reduced filtration activity, which subsequently increased to control levels upon continued exposure. Cu alone and in combination with Cd and Zn also significantly (P < 0.001) inhibited filtration relative to controls. This combination also progressively reduced respiratory activity with time, the maximum decrease being 80% after 96 h of exposure. Furthermore, impact of all three metals on both filtration rate and oxygen consumption was initially synergistic, but changed to antagonistic upon prolonged exposure up to 96 h.Deceased. Please send all correspondence and requests for reprints to Dr. S. Patel at the same address  相似文献   
127.
Increased use of farm machinery along with other agricultural inputs has enhanced the production and productivity of Indian farms. Simultaneously, it has also increased occupational health hazards on the farms. Major occupational health hazards are farm related injuries. Very little information is available about the type and nature of agricultural injuries on Indian farms. In the present study, agriculture injuries data were collected for the period 1996–2000 for the Etawah district of Uttar Pradesh in India. It has a total population of 1.4 million while 0.75 million were associated with agricultural activities. The agricultural injuries incidence rate was 0.8 per thousand workers per year in the study area. Out of all agricultural injuries, 9% injuries were fatal. The highest number of injury victims were in the age group of 30–44 years. The highest percentages of injured victims were literate but non-matric. The monetary loss due to agricultural injuries in the study area was estimated to be about US $730,000 per year. To minimize agricultural injuries, development of interventions and trainings needs to be organized at block levels for proper and safe operation of agricultural equipment.  相似文献   
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129.
In the past few decades, governments and international agencies have been placing more emphasis on the improvement of production technique, working conditions and reduction of the toxic emission to the atmosphere. In this context aqueous polyurethane dispersion was synthesized from depolymerised polyethylene terphthalate (PET) waste. 1,4-Butanediol was used in PET depolymerisation. Polyurethane dispersion films were characterized using differential scanning calorimeter, Fourier transform infrared spectroscopy, gel permeable chromatography, etc. Incorporation of PET waste in polyurethane dispersion was an added advantage in waste management and produced better quality polyurethane dispersion.  相似文献   
130.
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