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61.
The seeds of Zanthoxylum armatum DC, on hydrodistillation, yielded 1.2% of the essential oil. The oleoresins were extracted by a Soxhlet extractor using ethanol, ethyl acetate, and isopropyl alcohol. Gas chromatography-mass spectrometry analysis of the essential oil resulted in the identification of 38 components, of which linalool (62%) and limonene (18.1%) were the major components. The major components of oleoresins were linoleic acid, palmitoleic acid, and linalool. The antioxidant potential of essential oil and oleoresins were evaluated by 2,2′-diphenyl picrylhydrazyl radical scavenging, Fe2+ chelating, ferric thiocyanate method, and various lipid peroxidation assays. The essential oil showed maximum antioxidant potential, whereas oleoresins showed moderate antioxidant activity.  相似文献   
62.
Least-squares spline interpolation techniques are reviewed and presented as a mathematical tool for noise reduction and interpolation of diffusion profiles. Numerically simulated diffusion profiles were interpolated using a sixth-order spline. The spline fit data were successfully used in conjunction with the Boltzmann-Matano treatment to compute the interdiffusion coefficient, demonstrating the usefulness of splines as a numerical tool for such calculations. Simulations conducted on noisy data indicate that the technique can extract the correct diffusivity data given compositional data that contain only three digits of information and are contaminated with a noise level of 0.001. Splines offer a reproducible and reliable alternative to graphical evaluation of the slope of a diffusion profile, which is used in the Boltzmann-Matano treatment. Hence, use of splines reduces the numerical errors associated with calculation of interdiffusion coefficients from raw diffusion profile data.  相似文献   
63.
This paper deals with the problem of navigation and planning of an automated warehouse equipped with mobile robotic devices. A generalised layout of the warehouse is considered here, which is a modular construction type. The path planning algorithm (optimises the path for the shortest distance to the goal) and the collision avoidance strategy for a multiple robot environment are developed based on velocity and distance bounds. The landmarks are assumed to supply all pertiment information regarding the module identification and the movement directions, while the sensors are assumed to be capable of maintaining the robot in its correct track and understand the knowledge contained in the landmarks. The path planning and collision avoidance algorithms are programmed and simulated for a multiple robot environment in a construction site warehouse.  相似文献   
64.
This brief note obtains expressions for Interval Reliability of a 2-unit stand-by repairable system by using the regenerative point technique of the Markov Renewal Process.  相似文献   
65.
A new approach to study organic solar cell using Lambert W-function   总被引:2,自引:0,他引:2  
Organic photovoltaic solar cells bear an important potential of development in the search for low-cost modules for the production of domestic electricity. One of the main differences between inorganic and organic solar cells is that photo-excitation in these materials does not automatically lead to the generation of free charge carriers, but to bind electron–hole pairs (exciton) with a binding energy of about 0.4 eV. Till now various numerical methods using approximations have been reported to study different aspects of organic solar cells. For the first time an accurate method using Lambert W-function is presented to study different parameters of organic solar cells.  相似文献   
66.
BACKGROUND: Iron, folate, and vitamin B12 deficiencies have adverse effects on pregnancy outcome. In India, data on the concomitant prevalence of these deficiencies among pregnant women are meager. OBJECTIVE: We conducted a community-based study to assess the prevalence of deficiencies of iron, folate, and vitamin B12 among pregnant women in a rural block of Haryana State. METHODS: The study was approved by the ethics committee of the All India Institute of Medical Sciences, New Delhi. A total of 283 pregnant women were enrolled in the study. After oral informed consent had been obtained from the women, blood was drawn from the antecubital vein for estimation of the levels of serum ferritin by enzyme-linked immunosorbent assay (levels < 12 ng/ mL were considered as indicative of poor iron stores); serum folate was determined by radioimmunoassay (levels <3 ng/mL were considered as indicative of poor folate stores); and serum vitamin B12 was estimated by the microbiologic method (levels < 200 pg/mL were considered as indicative of poor vitamin B12 stores). RESULTS: The results indicated that 67.7%, 26.3%, and 74.1% of the women had poor iron, folate, and vitamin B12 stores, respectively. Concomitant deficiencies of iron, folate, and vitamin B12 occurred in 16.2% of the women. We found that 59.9% of the women were consuming less than 75% of the recommended daily caloric allowance (2175 kcal), indicating an overall poor food intake. This could be one of the predominant reasons for poor iron, folate, and vitamin B12 stores among the women. CONCLUSIONS: Our findings suggest that apart from iron and folate, vitamin B12 deficiencies may play an important role in causing anemia.  相似文献   
67.
Microsystem Technologies - Modular multilevel converter (MMC) is an enhanced multilevel converter topology. It is widely used in research nowadays for its superior performance in high-voltage...  相似文献   
68.
The thermolysis of high energetic polynitro organic compounds has been reviewed in the present communication.  相似文献   
69.
Erörterungen zur homogenen Keimbildung und zur Berechnung der kritischen Übersättigung bei der Desoxidation von Eisenschmelzen mit Mangan. Behandlung des Wachstums der Desoxidationsprodukte durch Diffusion und Kollision. Aussagen über die zeitliche Verteilung der Desoxidationsprodukte unter Berücksichtigung von Stokes- und Gradient-Kollision. Angaben über die Bedeutung der Grenzflächenspannung zwischen Schmelze und Einschluß für die Abscheidung der Desoxidationsprodukte.  相似文献   
70.
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