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21.
Precipitation chemistry at sinhagad-a hill station in India   总被引:1,自引:0,他引:1  
The chemistry of precipitation in remote sites such as mountain tops is of interest in the study of atmospheric pollution and acid rain. The chemical composition measured at mountain site which is away from industrial and urban areas is useful as a reference level and it allows to determine the extent of anthropogenic contamination. Hence, rain water samples were collected at Sinhagad (18°21N, 73°45E, 1450 m asl during the monsoon season (June-September) of 1992 and were analysed for major ions. The precipitation samples collected at Sinhagad were alkaline in nature and pH values ranged between 5.9 to 6.76. The ionic composition was dominated by soil dust The concentration of Ca2+ was highest among all the ions. The concentrations of excess SO3 2– and NO4 were small (23.8 and 15.2 eq l–1 respectively) compared to the values of polluted regions in India. The correlation coefficient between the ions and pH values was calculated and it was found to be maximum in case of Ca2+. Precipitation samples collected at Sinhagad were alkaline owing to higher concentration of Ca2+ and lower levels of acidic pollutants (SO4 2– and NO3 ).  相似文献   
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Rain water and dustfall deposition samples were collected at Pune, an urban site (1992–98) and at Sinhagad, a rural site (1992–94). The samples were collected with wet-only and bulk collectors at Pune and with bulk collector at Sinhagad. The samples were analyzed for major ions, pH and conductivity. The study showed that the rain water at both places is alkaline (pH > 5.6). The average pH at Pune was 6.1. Neutralising components, indicated by Ca and non sea salt (nss) Mg have higher concentrations than the acidifying components SO4 and NO3. The wet deposition fluxes of all the ionic components were higher than the dustfall fluxes. Relative contribution from dustfall was largest for K, Ca, Mg and NO3. Dustfall was greater at Pune, compared to Sinhagad for all components and up to double for Ca.  相似文献   
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Four cultivars of strawberries (Senga Sengana, BFr77111, Elsanta, and Honeoye) were studied for their content of antioxidants, total antioxidant capacity, and low molecular weight carbohydrates in relation to harvest year, ripening stage, and cold storage. For ascorbic acid, chlorogenic acid, ellagic acid, and total antioxidative capacity, measured in both water-soluble and water-insoluble extracts, there was a 2-5-fold variation among cultivars. Unripe berries contained lower concentrations of chlorogenic acid and p-coumaric acid and also quercetin and kaempferol compared with riper berries. During cold storage for up to 3 days, relatively few changes in the concentration of the different antioxidants occurred. The concentrations of several investigated parameters were interrelated, for example, for ascorbic acid and water-soluble antioxidant capacity and for ellagic acid and water-insoluble antioxidant capacity. The dominating sugars in strawberries were fructose and glucose, but considerable amounts of sucrose were also present, and their contents varied among cultivars, giving a predicted glycemic index of approximately 81. Verbascose, raffinose, and stachyose were found in only minor amounts. The study shows that the concentration of a number of bioactive compounds in strawberries varied according to cultivar, ripening stage, and storage. This information should make it possible to select strawberries with an optimal content of bioactive compounds.  相似文献   
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Most of the fruits formed on muskmelon go to waste due to premature shedding, insect punctures and rotting. An experiment was conducted to test the value of controlling insect damage, eliminating contact of fruits with the soil, avoiding continuous contact of the same part of fruits with the soil, and prophylactic application of fungicides on and around fruits, in saving the fruits from rotting. Placing of fruits on polyethylene sheets was best in reducing the incidence of fruit rot, increasing the yield, and providing high net income. Spraying Bordeaux mixture (6:3:100) on and around the fruits was next best.  相似文献   
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Passive cutaneous anaphylaxis was produced in chickens with bovine serum albumin (BSA) and anti-BSA chicken serum. Colloidal carbon was then given intravenously to identify the leaky vessels. Examination of the resulting sequential changes revealed a marked increase in vascular permeability affecting the venules. A noteworthy feature of the reaction was the early participation of the basophils, which contained phagocytosed carbon particles. Eosinophils were absent.  相似文献   
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In the present study efficacy of single intradermal Johnin test, acid fast staining of faecal smear and IS 900 faecal polymerase chain reaction tests was evaluated in 200 goats for detection of Mycobacterium avium subsp paratuberculosis. Two hundred goats comprising 150 goats from an organised farm in Trichur district and 50 goats reared under field condition at farmers premise from Malappuram district of Kerala state formed the study population. Faecal smear from all the 200 goats was stained by Ziehl–Neelsen acid fast stain and faecal polymerase chain reaction (PCR) specific for M. avium subsp paratuberculosis (MAP); IS 900 was performed on all samples. All the animals were subjected to single intradermal Johnin test. Out of 200 goats screened for paratuberculosis, six goats (3%), 11 goats (5.5%) and 42 goats (21%) were found positive by Ziehl–Neelsen acid fast staining of faecal smear, single intradermal Johnin test and IS 900 PCR respectively. Results of the present study indicate that amplification of IS 900 insertion element was the most specific and sensitive diagnostic detection method. Single intradermal Johnin test and Ziehl–Neelsen acid fast staining did not show any significant difference.  相似文献   
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Sixty-five Solanum tuberosum group Andigena, Phureja and Stenotomum genotypes from an initial population of 1,500 were analyzed for phenylpropanoids, carotenoids, and antioxidant capacity. Total phenolic content ranged from 3 to 49 mg g?1 DW, total carotenoids from 4.1 to 154 μg/g DW, anthocyanins from 0.27 to 34 mg g?1 DW and antioxidant capacity from 60 to 1,767 μmol TE/g DW. HPLC analysis of phenolic extracts revealed that 5-O-chlorogenic acid (5CGA) was the most abundant polyphenol in all genotypes. Ten genotypes were independently grown out for more in-depth phytonutrient analysis. The Phureja genotypes RN 27.01 had the highest polyphenol, anthocyanin and antioxidant content, while RN 39.05 had the highest carotenoid content. The tuber percentage dry matter varied markedly among the ten genotypes, influencing the phytonutrient values when expressed on a dry weight basis. Chlorogenic acid concentrations ranged from 1.7 to 29.4 mg g?1 DW and kaempferol-3-rutinose was present up to 3 mg g?1 DW. Petunidin-3-O-coum-rutinoside-5-O-glu or pelargonidin-3-O-coum-rutinoside-5-O-glu were the most abundant anthocyanins. The principal carotenoids were lutein, zeaxanthin, violaxanthin, and antheraxanthin, but no one carotenoid was predominant in all genotypes. These findings further support utilization of Phureja group germplasm for phytonutrient enhancement efforts.  相似文献   
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