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191.
Land degradation by soil erosion is one of the most serious problems and environmental issues in many ecosystems of arid and semi-arid regions. Especially, the disturbed areas have greater soil detachability and transportability capacity. Evaluation of land degradation in terms of soil erodibility, by using geostatistical modeling, is vital to protect and reclaim susceptible areas. Soil erodibility, described as the ability of soils to resist erosion, can be measured either directly under natural or simulated rainfall conditions, or indirectly estimated by empirical regression models. This study compares three empirical equations used to determine the soil erodibility factor of revised universal soil loss equation prediction technology based on their geospatial performances in the semi-arid catchment of the Saraykoy II Irrigation Dam located in Cankiri, Turkey. A total of 311 geo-referenced soil samples were collected with irregular intervals from the top soil layer (0-10?cm). Geostatistical analysis was performed with the point values of each equation to determine its spatial pattern. Results showed that equations that used soil organic matter in combination with the soil particle size better agreed with the variations in land use and topography of the catchment than the one using only the particle size distribution. It is recommended that the equations which dynamically integrate soil intrinsic properties with land use, topography, and its influences on the local microclimates, could be successfully used to geospatially determine sites highly susceptible to water erosion, and therefore, to select the agricultural and bio-engineering control measures needed.  相似文献   
192.
One hundred unpackaged rice samples, each weighing 500 g, were randomly collected at retail stores and open markets in the largest rice growing area (Thrace) in Turkey and analysed for mould counts, predominant mould genera, moisture content and mycotoxin levels. Mould counts ranged from 1.0 × 101 to 1.5 × 104 cfu/g in 70 of 100 samples, and the correlation between moisture content and mould count was significant (p????0.05). Aspergillus spp. and Penicillium spp., potential mycotoxin producers, were the dominant moulds. In one area from which samples were collected, the mycotoxin content of rice was found to be positively correlated with moisture content; samples with higher moisture also contained higher numbers of moulds. The levels of total aflatoxins, aflatoxin B1 and ochratoxin A were higher than the maximum tolerable limits (4, 2 and 3 ??g/kg, according to the EC Regulation and the Turkish Food Codex) for 32, 14 and 30 of 100 rice samples, respectively. This is the first comprehensive report of ochratoxin A levels in rice grown in Thrace, Turkey.  相似文献   
193.
Pre-harvest sprouting refers to the precocious germination of the grain in the spike prior to harvest as a result of moist weather conditions at harvest time. From the agricultural viewpoint, it is necessary to impose an exogenous dormancy to wheat seeds in order to improve the resistance of seed to pre-harvest sprouting. In this regard, we found that clove bud essential oil is a strong inhibitor for wheat seed germination. The extract obtained from clove bud by supercritical fluid extraction using CO2 as solvent minimized the number of extracts to two compounds, eugenol and eugenyl acetate. Eugenol, as the main constituent of the oil, was responsible for its strong inhibitory activity in wheat seeds. The aqueous solution of clove bud oil was submitted to germination assay at various concentrations from 50 to 400 mg/L. Complete inhibition of seed germination was recorded when the concentration was 400 mg/L. Roots and sprouts have similar sensitivity to inhibitory effect. In an empirical study, the synergistic cooperation of eugenol and eugenyl acetate from clove bud oil in the inhibition of seed germination was found to be a 1:1 ratio. The clove bud essential oil is widely available and will broaden the horizon of applications for natural and safe inhibitors in the fields.  相似文献   
194.
In 1999, two earthquakes in northwest Turkey caused heavy damage to a large number of industrial facilities. This region is the most industrialized in the country, and heavy damage has a significant economic influence. Industrial storage tanks, ruptured by earthquakes, exascerbate damage through the spread of fire. Storage tanks are uniquely structured, tall cylindrical vessels, some supported by relatively short reinforced concrete columns. The main aim of this study is to evaluate the earthquake performance of Turkish industrial facilities, especially storage tanks in terms of earthquake resistance. Modeling a typical storage tank of an industrial facility helps to understand the structure’s seismic response. A model tank structure was modelled as a solid with lumped mass and spring systems. Performance estimation was done with 40 different earthquake data through nonlinear time history analyses. After the time history analyses, fragility analyses produced probabilistic seismic assessment for the tank model. For the model structure, analysis results were evaluated and compared. In the study, vulnerability of storage tanks in Turkey was determined and the probabilistic risk was defined with the results of the analysis.  相似文献   
195.
196.
Women have the right to support that enables them to breastfeed. Supporting breastfeeding in emergencies is important because artificial feeding places mothers and children at risk. In emergencies, artificial feeding is dangerous to the infant, difficult and requires substantial resources. In contrast, breastfeeding guards infant health. It is also protective against postpartum haemorrhage, maternal depletion, maternal anaemia and closely spaced births and should therefore concern not only nutritionists, but also those involved in reproductive health. However, it is common for women's ability to breastfeed to be undermined in emergencies by the indiscriminate distribution of breast-milk substitutes and the absence of breastfeeding support. Controlling the distribution of breast-milk substitutes, providing supportive environments, and appropriate medical and practical assistance to breastfeeding women safeguards the health and well-being of mothers and babies. Greater collaboration between the nutrition and reproductive health sectors is required to promote best practice in protecting breastfeeding women and their children in emergencies.  相似文献   
197.
Journal of Polymers and the Environment - A new biocomposite cross-linked glutaraldehyde-chitosan/MgO/Fe3O4 (CTS-GL/MgO/Fe3O4) adsorbent with magneto-responsiveness was prepared and applied for the...  相似文献   
198.
Journal of Polymers and the Environment - In this study, Acrylic acid (AA), acrylamide (AM), and 16,16-dimethylheptadecan-1-amine (PJM-T) were copolymerized using gamma irradiation with 60Co...  相似文献   
199.
Environment Systems and Decisions - For mission critical (MC) applications such as bushfire emergency management systems (EMS), understanding the current situation as a disaster unfolds is critical...  相似文献   
200.
Environmental Fluid Mechanics - In this paper, the linear stability of sand waves sheared by a turbulent flow is analyzed. The velocity distribution in the streamwise direction is considered to...  相似文献   
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