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121.
A powerloom plant consists of two units A and B(n) connected in series. Unit B(n) has n components in parallel redundancy that carry threads of different varieties/colours to unit A. Unit A is the strategic unit that weaves these threads together and produces a long piece of cloth of some standard size. Failure of unit A makes the entire system fail whereas the failure of k components out of n in unit B(n) results in the system working in a degraded state. The present paper deals with the reliability analysis of the powerloom plant with a cold standby for its strategic unit. The common cause failure and critical human errors have also been considered to avoid overestimation of the reliability of the system. Results of Dhillon [Int. J. cyst. Sci. 23, 1277–1287 (1992)] have been deduced as a particular case of our result. 相似文献
122.
123.
SP Yadav M Gopal I Chadha P Gulati R Sharma SK Marya R Yadav 《Canadian Metallurgical Quarterly》1997,95(5):129-30, 134
Infertility has a fair degree of male factor contribution in its aetiology, hence needs complete evaluation of male partner especially the status of spermatogenesis. In the present study comparative evaluation of fine needle aspiration cytology (FNAC) and biopsy of testis showed 90% accuracy of FNAC in respect of histopathological diagnosis of spermatogenesis. FNAC is a safe, fairly accurate, outdoor investigation in infertile man and it is devoid of the complications of haematoma formation, suppression of spermatogenesis and antigenic stimulation as seen with testicular biopsy. 相似文献
124.
125.
Respiratory obstruction caused by a round worm is rate. A fatal case of the complication in a three-year-old child was encountered at the Nehru Hospital attached to the Postgraduate Institute of Medical Education and Research, Chandigarh, India. 相似文献
126.
Effect of ferrocene concentration on the synthesis of bamboo-shaped carbon-nitrogen nanotube bundles
Yadav RM Shripathi T Srivastava A Srivastava ON 《Journal of nanoscience and nanotechnology》2005,5(5):820-824
We have investigated the effect of ferrocene concentration on the synthesis of carbon-nitrogen (C-N) nanotubes. The bamboo-shaped carbon-nitrogen nanotubes were synthesized by spray pyrolysis of Fe(C5H5)2 and CH3CN solution using argon as a carrier gas at the optimum temperature of approximately 900 degrees C. The effect of ferrocene concentration on the length and concentration of nitrogen in nanotubes was studied. Micro-structural features of the nanotubes were monitored employing scanning and transmission electron microscopic techniques. SEM studies reveal that with decreasing ferrocene concentration from 25 mg ml(-1) to 5 mg ml(-1), the length of the nanotubes vary from 80 microm to 430 microm. A feasible growth model has been described and discussed. X-ray photoelectron spectroscopic studies have confirmed the formation of nitrogen-doped carbon nanotubes. These studies reveal that the nitrogen concentration in the nanotubes decreases with the increase of ferrocene concentration. The present synthesis route also provides means of producing carbon nanotubes with different concentrations of nitrogen. 相似文献
127.
128.
Pheochromocytoma is rarely observed during pregnancy and not easily diagnosed, especially since the clinical manifestations may mimic common gravid hypertension. The maternal and fetal prognosis depends on early diagnosis and multidisciplinary management preparing for tumor resection. Appropriate laboratory tests easily provide the positive diagnosis, if they are ordered. The tumor is localized by ultrasonography or magnetic resonance imaging (MRI). By prescribing an alpha-blocker, it is possible to prepare the resection as a function of term, before or after delivery. This strategy allows a reduction in maternal and fetal mortality which is high if the pheochromocytoma goes undiagnosed. 相似文献
129.
Enterokinase has a critical role in initiating proteolytic digestion by hydrolysing the conversion of pancreatic trypsinogen into trypsin. The enzyme is synthesised by enterocytes of the proximal small intestine and initially incorporated into the brush border from where it is released into the intestinal lumen by the action of pancreatic secretions. The aim of the study was to analyse enterokinase activity in the duodenal mucosa of infants with diarrhoeal disease including cow's milk protein-sensitive enteropathy. Our observations show that the mean depletion of enterokinase was only 17% compared to 60-80% for other brush border enzymes like disaccharidases, peptidases and alkaline phosphatases in infants with diarrhoea. This suggests that enterokinase activity in the small bowel enteropathies may be dependent not only on the degree of mucosal damage specifically but also on the extent of damage to the goblet cell population where the enzyme is synthesised. Thus the enterokinase activity was reduced in acute and chronic diarrhoea with marked mucosal damage where significant reduction of goblet cell population was evident but the enzyme was relatively little affected when the mucosa was damaged mildly. 相似文献
130.
Yadav AK Kaushik CP Haritash AK Kansal A Rani N 《Journal of hazardous materials》2006,128(2-3):289-293
Defluoridation of groundwater using brick powder as an adsorbent was studied in batch process. Different parameters of adsorption, viz. effect of pH, effect of dose and contact time were selected and optimized for the study. Feasible optimum conditions were applied to two groundwater samples of high fluoride concentration to study the suitability of adsorbent in field conditions. Comparison of adsorption by brick powder was made with adsorption by commercially available activated charcoal. In the optimum condition of pH and dose of adsorbents, the percentage defluoridation from synthetic sample, increased from 29.8 to 54.4% for brick powder and from 47.6 to 80.4% for commercially available activated charcoal with increasing the contact time starting from 15 to 120 min. Fluoride removal was found to be 48.73 and 56.4% from groundwater samples having 3.14 and 1.21 mg l(-1) fluoride, respectively, under the optimized conditions. Presence of other ions in samples did not significantly affect the deflouridation efficiency of brick powder. The optimum pH range for brick powder was found to be 6.0-8.0 and adsorption equilibrium was found to be 60 min. These conditions make it very suitable for use in drinking water treatment. Deflouridation capacity of brick powder can be explained on the basis of the chemical interaction of fluoride with the metal oxides under suitable pH conditions. The adsorption process was found to follow first order rate mechanism as well as Freundlich isotherm. 相似文献