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101.
Chaulya S. K. Chakraborty M. K. Ahmad M. Singh R. S. Bondyopadhay C. Mondal G. C. Pal D. 《Water, air, and soil pollution》2002,140(1-4):21-55
All major mining activities, particularly opencast coal mining,directly or indirectly contribute to the problem of air pollution.Therefore, air quality assessment and prediction arerequired to prevent and minimize the air quality deteriorationdue to various opencast coal mining operations. Determination ofemission rates for these activities is the first and foremostconcern. In view of the above, this study was undertaken to determinate emission rates and to develop empericalformulae to calculate emission rates of various opencast coalmining activities.To achieve the objectives, seven coal mining sites were selectedto generate site-specific emission data by considering miningpractices, method of working, geographical location,accessibility and above all resourceavailability. The study covers various mining activities andlocations including drilling, overburden loading and unloading,coal loading and unloading, the coal handling plant, the exposedoverburden dump, the stock yard, the workshop, the exposed pit surface roadsand haul roads.Based on the study, a set of twelve emperical formulae have beendeveloped for calculation of suspended particulate matter (SPM)emission rates from various opencast coal mining activities. Theemission of gaseous pollutants (sulphur dioxide and nitrogenoxide) has been found negligible for various mining activities.Therefore, observation for gaseous pollutants has been consideredfor overall mine activities and empirical formulae have subsequently beendeveloped.The developed empirical formulae were calculatedby a field study at another coal mine. The measured andcalculated values of emission rate were compared for eachactivity. Average correlation between the measured andcalculated values for different activities was estimated to be 85.6–99.9%, which indicates fairly good accuracy.Validation of the study was also carried out by means of thefugitive dust model (FDM) using the calculated emissionrate data from the empirical formulae for each mining activity of amine, meteorological data and other details as input.The average accuracy between measured and predictedvalues of concentration of SPM at certain receptor locations wasfound to be 79%. A user-friendly emission software called`EmissCalc' was developed to calculate emission rate, whichcan be used as input for different air quality models. 相似文献
102.
Muhammad Amjad Javaid Akhtar Muhammad Anwar-ul-Haq Muhmmad Atif Riaz Zulfiqar Ahmad Saqib Behzad Murtaza 《Journal of plant nutrition》2016,39(13):1926-1935
To check the efficacy of potassium in alleviating oxidative stress under salt stress, salt-tolerant (Indent-1) and salt-sensitive (Red Ball) tomato (Lycopersicon esculentum Mill.) genotypes were exposed to three levels of sodium chloride (NaCl) (0, 75, 150 mM) and two levels of potassium (4.5 and 9 mM) in solution and foliar form. Thirty days of treatments revealed that increasing NaCl stress increased lipid peroxidation (malondialdehyde, MDA) and correspondingly the activity of antioxidant enzymes (superoxide dismutase, SOD; catalase, CAT; and glutathione reductase GR) in both genotypes. However, higher potassium (K) level in solution or foliar spray during the salt-induced stress decreased MDA and antioxidant activity and increased the growth in salt-tolerant genotype than in the salt-sensitive genotype. Decrease in MDA concentration, activity of antioxidant enzymes, and increase in the growth of tomato plants by the application of potassium under salt stress suggest that potassium is an effective ameliorating agent against salt-induced oxidative damage. 相似文献
103.
Seed treatment with thiamine mononitrate significantly increased germination rate of bean (Phasenius vulgaris L.) seedlings germinated at high soil moisture levels and low night-temperature (5° C). Beneficial effects of thiamine applications on germination were also observed in soil-free germination tests when the seeds were submerged in water for 1–4 d at 18°C. Optimum response was achieved at thiamine concentrations of 3 mM, applied during the first 24 h of imbibition. As an early response to the thiamine treatment, vital staining with triphenyltetrazolium chloride revealed a lower proportion of damaged tissue of the embryonic axes. In later stages of seedling development, thiamine seed treatment resulted in a lower proportion of abnormal seedlings with malformations of the shoot apex and of the primary leaves. The beneficial effect of thiamine was more pronounced when the temperature during submergence was kept at 25° C compared to 5° C. There was no response to thiamine applications when the germinating seeds were exposed to low temperature treatments only. The thiamine effect could be mimicked by raising the osmotic potential of the incubation medium, indicating a relationship to soaking injuries. The results suggest that normal seedling development may be impaired by thiamine deficiency in the embryonic tissue induced by soaking injury, whereas low temperatures are not involved as a stress-factor. 相似文献
104.
Renu Pandey Krishna Kant Dubey Altaf Ahmad Rakshanda Nilofar Rachana Verma Vanita Jain 《Journal of plant nutrition》2015,38(8):1196-1217
Cultivars of Triticum aestivum, T. durum, and Secale cereale were grown at low (2 μM) and sufficient (500 μM) phosphorus (P) under ambient carbon dioxide (380 μmol mol?1; aCO2) and elevated CO2 (700 μmol mol?1, eCO2) to study responses of cereal species in terms of growth and P utilization efficiency (PUE) under P x CO2 interaction. Dry matter accumulation increased under eCO2 with sufficient P. Nevertheless, dry matter accumulated at eCO2 with low-P was similar to that obtained at aCO2 with sufficient P. Leaf area was 43% higher under eCO2 with sufficient P. Significant increase in lateral root density, length and surface area were noted at low-P under eCO2. Phosphorus use efficience (PUE) increased by 59% in response to eCO2 in low-P plants. Thus, eCO2 can partly compensate effect of low-P supply because of improved utilization efficiency. Among cereals, durum wheat was more suitable in terms of PUE under high CO2 and limiting P supply. 相似文献
105.
Capillary column gas chromatographic determination of trace residues of the herbicide chlorsulfuron in agricultural runoff water 总被引:1,自引:0,他引:1
I Ahmad 《Journal of the Association of Official Analytical Chemists》1987,70(4):745-748
A capillary column gas chromatographic method is described for determining parts-per-trillion (ppt) levels of chlorsulfuron in agricultural runoff water. The water sample is acidified with acetic acid and extracted with methylene chloride. The chlorsulfuron in the extracts derivatized to its monomethyl derivative. After Florisil column cleanup, the methylated chlorsulfuron is determined by electron-capture gas chromatography. Recovery of chlorsulfuron from fortified water samples is greater than 80%. Detection limit of the method is 25 ng chlorsulfuron/L water (25 ppt). There are 2 reaction sites on the chlorsulfuron molecule, both of which are susceptible to methylation leading to monomethyl chlorsulfuron and dimethyl chlorsulfuron. A procedure is described to methylate selectively the sulfonamide nitrogen of chlorsulfuron. 相似文献
106.
A simplified method that combines extraction, partitioning, and cleanup in a single step for measuring p,p'-DDT and its metabolites in fish is described. Minced fish samples are emulsified with disodium hydrogen orthophosphate and trisodium citrate, ground with sodium sulfate, and eluted from a chromatographic column prepacked with alumina and silicic acid. The fats and fatty acids are solubilized and easily extracted from the tissues and retained by the column, while p,p'-DDT and its metabolites are quantitatively eluted with 40 mL n-hexane. The eluate is directly applied to a gas chromatographic column. Average recoveries of p,p'-DDT and its metabolites added to fish in vitro are 81%. The average coefficient of variation for recoveries of p,p'-DDT and its metabolites is less than 6.5% and the detection limit is 0.001 micrograms/g for p,p'-DDE, thus making this method very suitable for residue analysis. 相似文献
107.
Saeed Yousefzadeh Mostafa Govahi Ozra Sadat Khatamian Oskooie 《Journal of plant nutrition》2015,38(12):1862-1876
We conducted field experiments in two locations to investigation of organic and chemical fertilizer on soil characteristics and essential oil yield in dragonhead. Results showed that the inoculation of bacteria with the seeds in location 1 and also the inoculation of bacteria with the seeds of G1 genotype in location 2 than G2 genotype increased the total soil nitrogen content. The application of azocompost and its inoculation with urea's chemical fertilizer comparing to chemical control, it increase the soil carbon content. Results indicated that by increasing azocompost content with a linear procedure bulk density increased. Results showed that application of 100% azocompost treatment had the highest electrical conductivity in the soil. According to the results, the main effect of genotype and fertilizer regime and also two-way interaction (bacteria × fertilizer) had significant relationship with essential oil yield. 相似文献
108.
Growth,survival, and heavy metal (Cd and Ni) uptake of spinach (Spinacia oleracea) and fenugreek (Trigonella corniculata) in a biochar‐amended sewage‐irrigated contaminated soil
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Uzma Younis Muhammad Farooq Qayyum M. Hasnain Raza Shah Subhan Danish Ahmad Naeem Shahzad Saeed Ahmad Malik Seema Mahmood 《植物养料与土壤学杂志》2015,178(2):209-217
Irrigation of arable land with contaminated sewage waters leads to the accumulation of trace metals in soils with subsequent phyto‐/zootoxic consequences. In this study, biochar derived from cotton sticks was used to amend an agricultural silt‐loam soil that had been previously irrigated with trace metal contaminated sewage waters. Metal accumulation and toxicity to spinach (Spinacia oleracea) and fenugreek (Trigonella corniculata) was investigated by measuring concentrations of Cd and Ni in plant tissues and various photosynthetic and biochemical activities of plants. Positive impacts of biochar on both spinach and fenugreek were observed in terms of biomass production that increased from 29% to 36% in case of spinach, while for fenugreek this increase was 32% to 36%. In the control treatment there was an increase in malondialdihyde, soluble sugar, and ascorbic acid contents, indicating heavy metal stress. Biochar applications increased soluble proteins and amino acids in plants and reduced the uptake of Cd from 5.42 mg kg?1 at control to 3.45 mg kg?1 at 5% biochar amended soil and Ni (13.8 mg kg?1 to 7.3 mg kg?1 at 5% biochar) by the spinach plants. In fenugreek, the Cd was reduced from 7.72 mg kg?1 to 3.88 mg kg?1 and reduction in Ni was from 15.45 mg kg?1 to 9.46 mg kg?1 at 5% biochar treated soil, reducing the possibility of transfer up the food chain. This study demonstrates that the use of biochar made from cotton‐sticks, as an amendment to arable soils that have received contaminated irrigation water, could improve plant growth and decrease Cd and Ni uptake to crops, alleviating some of the negative impacts of using sewage waters on arable land. 相似文献
109.
Jezie A. Acorda DVM Magr Haruo Yamada DVM DVSc Seyed Mehdi Ghamsari DVM 《Veterinary radiology & ultrasound》1995,36(4):322-326
Ultrasonography of the liver of 181 Holstein-Friesian cows was performed and blood samples were collected for analysis. The hepatic ultrasonograms were evaluated and the echoes were analyzed digitally. After slaughter, liver specimens were taken and examined histopathologically. Of the 181 animals, 120 had a normal liver and 61 had hydropic degeneration of the liver, diagnosed through histopathologic examination. Diagnostic accuracy rates for hydropic degeneration were determined based on the following test positive conditions: a) for biochemical analysis—high levels of aspartate aminotransferase, alanine aminotransferase, total bilirubin and non-esterified fatty acids; b) for ultrasonography—presence of dark pattern and blurring of edges; and c) for digital analysis—low echo means at 1 cm and 3 cm from the hepatic surface. Digital analysis had the highest overall specificity, accuracy and positive predictive values for hydropic degeneration, followed by ultrasonography. The results suggest that ultrasonography and digital analysis of hepatic ultrasonograms can be used for diagnosis of hydropic degeneration of the liver in place of biochemical analysis. 相似文献
110.