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81.
Concentrations of HCH and DDT in soil, water and whole blood were determined in two areas under malaria control. These were, (i) bioenvironmental control of malaria at BHEL, and (ii) residual spraying of insecticides in rural and urban area of Bahadrabad PHC of Hardwar district. Mean concentrations of HCH in soil and whole blood samples from BHEL was 2.26 micrograms/kg and 1.20 micrograms/l and from Bahadrabad 61.12 micrograms/kg and 24.3 micrograms/l respectively. Similarly, the mean concentration of DDT in soil and whole blood from BHEL was 3.68 micrograms/kg and 4.71 micrograms/l, while in Bahadrabad 270.51 micrograms/kg and 38.13 micrograms/l respectively. HCH and DDT were never detected in any water samples from BHEL area, while the mean concentration of these compounds in water of Bahadrabad area was 0.18 and 0.07 microgram/l respectively. Residual level of HCH and DDT were 27 and 73.5 times higher in soil and 20.2 and 8.1 times higher in whole blood samples from Bahadrabad as compared to their corresponding values from BHEL respectively.  相似文献   
82.
BACKGROUND: The effects of salt on the essential oil yield and fatty acid composition of aerial parts of two marjoram varieties were investigated. Plants with 6 leaves were treated with NaCl (75mM). RESULTS: Salt treatment led to a reduction in aerial part growth. Salinity increased the fatty acid content more significantly in Tunisian variety (TV) than in Canadian variety (CV). CV showed an increase in double‐bond index (DBI) and a decrease in malondialdehyde content under salt stress, while the opposite was observed in TV. The DBI was mainly affected by a strong reduction in oleic and linoleic acids in TV, whereas a strong stimulation of linoleic acid in CV was observed. Salt decreased and increased the essential oil yield in TV and CV respectively. The main constituents of the essential oil of TV were trans‐hydrate sabinene and terpinen‐4‐ol, which showed a significant decrease under salt stress. In contrast, the main constituents of the essential oil of CV were sabinene and trans‐hydrate sabinene, which showed a significant decrease and increase respectively under salt stress. CONCLUSION: Marjoram oil is a rich source of many compounds such as essential oils and fatty acids, but the distribution of these compounds differed significantly between the two varieties studied. Copyright © 2011 Society of Chemical Industry  相似文献   
83.
Among different type of transition metal oxides, tungsten trioxide (WO3) is a suitable candidate for electronic device fabrication due to its n-type property and wide band gap. Herein, one-dimensional tungsten trioxide (WO3) nanorods were achieved from an aqueous solution of sodium tungstate dihydrate (Na2WO4·2H2O) and sodium chloride (NaCl) in an acidic media by a time-optimized hydrothermal synthesis in autoclave at 180°C or different synthesis durations. For studying morphology and size of obtained powder, X-ray diffraction (XRD), scanning electron microscope (SEM), and high resolution transmission electron microscope (HRTEM) were applied. Finally, WO3 nanorods of about 2–3 μm in length and 100–200 nm in diameter were obtained during 3 h hydrothermal process.  相似文献   
84.
Electrophoretic deposition (EPD) has been known as a cost-effective and simple method in shaping or coating ceramic parts. Usefulness of this electrically driven method becomes more pronounced when it is applied for manipulating nanosize materials. Our findings in this area have showed that nanoparticle manipulation with EPD method is possible through applying low frequency alternating current (AC) electric fields. In our previous work, we explained how nanoparticles fill the non-conductive gap between two in-plane electrodes at frequency of 1 Hz. In this work, we used the similar idea to deposit TiO2 nanoparticles on non-conductive Alumina base in direction parallel to the electrode edge. The length and width of TiO2 deposited line was in the order of micrometer and coherency of deposited layer was good. It was concluded that with designing different electrode shapes, micro-patterning of ceramic nanoparticles on different substrates via low frequency AC electrophoretic deposition is possible.  相似文献   
85.
The aim of this study was to determine and to compare the presence of oxytetracycline (OTC) residues in raw and cooked (boiled) meat before and after withdrawal period with the Maximum Residue Limits (MRL) using biological and physicochemical techniques. In animal building of 2000 broiler chickens (Gallus domesticus, breed ISA F15) and under the same conditions, 12 healthy adult chickens were selected and divided in two groups (n?=?6 in each group). The sample was treated by Oxytetracycline® 20% (0.4 g/kg) during 3 days. Juices and muscles tissues were sampled twice for this assay: first, the broiler chickens were slaughtered (n?=?6) 24 h after the third day of treatment. However, the second sampling (n =?6) was performed 24 h after the end of the withdrawal period. For each portions of sample, the juice meat and muscle tissues samples were collected after cooking at 80 °C during 45 min and after freezing/defrosting for the raw meat. Biological methods consisted of using four plates test (FPT) to pre-screening and Premi®Test to screening. Finally, to confirm and to quantify the accurate level of OTC in positive samples, ultra-high-performance liquid chromatography–tandem mass spectrometry (UHPLC-MS/MS) measurements were conducted. The FPT test showed that all samples were positive. While the Premi®Test analysis showed negative results for raw meat tested and positive results for juice of meat cooked in both samples. The obtained results using UHPLC-MS/MS methods confirmed the previously results. Thus, the presence of such toxic substances in our diet constitutes a major health risk for consumers, requiring the establishment of an adequate monitoring system. There is a paucity of official withdrawal periods for veterinary medicinal products in cooking meat; a relationship between the concentrations of residues of antibiotics after waiting period and cooking is not established since meat is always cooked before consumption.  相似文献   
86.
Pressure die casting mould manufacturing companies have difficulties assessing manufacturing costs for bid generation. In particular, manufacturing effort of mould cavities could hardly be predicted accurately. Due to varying complexity of casting part geometry, processing time of manufacturing cavities appears to be a rather unpredictable factor influencing costs calculation of moulds. This article introduces a novel method for generating and analysing computer-aided design (CAD) models of mould cavities to compute the tool accessibility. Using geometrical information of cavities, working areas for different milling head geometries are determined, and processing times are calculated. Thereupon, a three-step accessibility analysis (AA) has been conducted. Beside the AA method, a CAD-based application of the calculation tool ??visual form calculator?? (VFC), developed at IFW, is presented. Using the VFC, companies are now able to generate a virtual model of the contour element in order to assess mould costs accurately when analysing manufacturing processes of cavities.  相似文献   
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