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141.
A sensitive adsorptive stripping voltammetric method for the determination of simeton with universal buffer solution has been described. The method was based on the adsorption accumulation of simeton at a hanging mercury drop electrode. The overall reduction process is under controlled diffusion. The adsorptive peak was observed at ?0.8 V vs SCE in acidic solution 2 < pH < 6. The peak response was characterized with respect to pH, accumulation potential, time, and scan rate. The calibration plot was found to be linear from 1.13 × 10???5 to 3.5 × 10???8 M with a limit of detection of 2.0 × 10???8 M. Finally, the method has been applied for the determination of simeton in its formulations and vegetable samples.  相似文献   
142.
Journal of Material Cycles and Waste Management - In this study, pyrolysis of agricultural residues, such as rice straw (RS), wheat straw (WS), and sugarcane bagasse (SB), was performed in a...  相似文献   
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Summary Detailed analyses of the utilisation of the natural forest and its forest products by the community of a small Indian Himalayan village, reveal various interactions between the forest, the people, their agricultural systems and their methods of animal husbandry. Biomass flow systems have been identified and processes of forest and environmental degradation described.  相似文献   
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Environmental Science and Pollution Research - The major global concern on energy is focused on conventional fossil resources. The burning of fossil fuels is an origin of greenhouse gas emissions...  相似文献   
148.
Extraction and quantification of pesticide residue from the milk matrix at or below the established maximum residue limit (MRL) is a challenging task for both analytical chemists and the regulatory institutions to take corrective actions for the human health and safety. The main aim of the study is to develop a simple rapid and less expensive QuEChERS extraction and cleanup method for simultaneous analysis of 41 multiclass pesticide residue in milk by gas chromatography-electron capture detector (GC-ECD), followed by confirmation of the residues with gas chromatography-mass spectrometer (GC-MS). Effect of sorbent type, temperature, spiking concentration, matrix effect (ME), measurement uncertainty (MU), inter- and intra-assay repeatability, reproducibility of recovery, and trueness of the results were investigated to validate the effectiveness of the method. Limit of determination (LOD) and limit of quantitation (LOQ) for all the analytes ranged within 0.001–0.02 and 0.002–0.05 µg mL?1, respectively. The % recovery of all the pesticides ranged between 91.38 and 117.56% with relative standard deviation (RSD) below 2.79%. The MU for all the analytes was ≤29% of respective LOQs, and except for few pesticides, the ME was largely negative. The method fulfilled all the SANTE guidelines and thus can be extended for routine analysis of multiclass pesticide residue in milk.  相似文献   
149.
Increasing on-farm crop diversity is one agroecological approach to enhancing food self-sufficiency that helps small-scale farmers keep their food systems stable by reducing risks associated with stressors, such as a pest outbreaks or droughts. But understanding how crop diversity and food self-sufficiency are related is unknown. To explore this complex relation, this study presents household data (n = 1664) from Nepal to test the hypothesis that families with high crop diversity enjoy greater household food self-sufficiency. Data are presented for three districts that are representative of three distinct agroecological regions of the country: (1) Sarlahi, which is affluent, market-oriented, and on the plains; (2) Makwanpur District in the hills, which has well-developed integrated farm production; and (3) the mountainous District of Humla, which has the poorest quality environment and is the most remote. Results show that in the Humla District, families with greater crop diversity were more self-sufficient. In contrast, farmers in Makwanpur, who have already established a high degree of crop diversity based on vegetable production, do not benefit from additional crop diversity in terms of their ability to provide for themselves. Finally, data from Sarlahi show that families’ food self-sufficiency benefits from crop diversification. We conclude that boosting crop diversity is a viable strategy for maintaining stability in food systems, but this varies depending on the accessibility of a farm and, in particular, access to markets.  相似文献   
150.
Mustang, a mountainous region in the Kali Gandaki River Basin in western Nepal, has been increasingly experiencing climatic changes (e.g., higher temperatures). Rising temperatures lead to ecological shifts, which, in turn, can lead to the expansion of the lower limit for the cultivation of apple trees in this area. Apple cultivation can provide opportunities for adaptations under climate change through vulnerability reduction, income source diversification, livelihood improvement, and capacity building for farmers. As there is a lack of a strong basis to justify the expansion of apple cultivation in Mustang, this study examines the biophysical and socioeconomic suitability of apple cultivation in the area. Necessary data and information were collected from both primary and secondary sources. Findings of biophysical suitability using variable and equal weights to the indicators showed that 5.2 and 4.1 % of the areas are highly suitable for apple cultivation, respectively. However, not all potential farming areas are currently in use. Thus, there is the possibility to expand apple cultivation into unplanted areas and to integrate apple crops with other crops on cultivated lands. Increasing temperature may increase the suitable areas for the cultivation of apples in the coming years. High, benefit–cost ratio for land use confirmed the economic suitability of apple farming when compared to other land uses. The social suitability assessment showed no social discords, conflicts, or disagreements with apple cultivation, which is a positive indicator for the expansion of apple cultivation in western Nepal.  相似文献   
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