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81.
A modification of an existing technique for thermistor linearization is presented. A temperature-measuring circuit using a thermistor in a specially designed pulse generator is used to obtain a highly linear relation between absolute temperature and frequency. The use of a general-purpose operational amplifier and two switching transistors in the design of the pulse generator provides a temperature scale that is linear over a wide range of values on a high degree of sensitivity. The result shows that an extremely high degree of linearity is achieved by this method 相似文献
82.
S Sengupta T Velpandian P Sapra P Mathur SK Gupta 《Canadian Metallurgical Quarterly》1998,11(4-5):273-278
Nimesulide is a newer non-steroidal anti-inflammatory drug (NSAID) with selective cyclo-oxygenase (COX)-2 blocking property and has demonstrated a potent analgesic and anti-inflammatory activity on oral and rectal administration. However, the Cmax through both these routes is reached only after 3 h of administration. Dose-dependent gastrointestinal side effects also limit the concentration of drug that can be achieved at the site of inflammation when administered through these routes. The present study was conducted to evaluate the antinociception induced by a new gel formulation of nimesulide when applied on the skin. Efficacy of topical nimesulide gel 1% (w/w) was studied on mice in the acetic-acid-induced writhing, tail flick latency (TFL) test and formalin-induced pain models. The antinociceptive effect of nimesulide was compared to diclofenac gel (1% w/w). Both the drugs induced dose-dependent analgesia with peak effect seen between 90 and 120 min after treatment. Greater antinociceptive effect (expressed as percent maximum possible effect) was seen in the writhing test than in the TFL test, indicating the peripheral action of both drugs. Nimesulide evidenced significant protection in the first phase of formalin-induced pain indicating modulation of peripheral nociceptors unlike other conventional NSAIDs. This suggests that COX-2 may be a primary contributor to afferent evoked increase in prostanoid-mediated changes in pain processing. Antinociception seen following drug application on the skin was lower than that seen on intraperitoneal administration, indicating localised action following topical application. The findings of the present study suggest that the transgel formulation of nimesulide provides significant analgesic activity when applied topically. 相似文献
83.
This paper deals with the propagation of 2-dimensional waves in a thermo-elastic micropolar solid layer which can stretch and contract. Thermo-elastic Rayleigh wave velocity equation in the micropolar medium with stretch has been deduced from the above theory. The wave velocity equation obtained is in agreement with the classical result of Rayleigh when the layer is unstretched and thermal and micropolar effects are negligibly small. 相似文献
84.
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86.
The efficiency and selectivity of two approaches for introducing alkoxysilane functionality to polyethylene (PE) are examined along with the moisture‐curing performance of the resulting products. Although the peroxide‐initiated grafting of vinyltriethoxysilane to PE is accompanied by undesirable crosslinking, comparable silane contents can be introduced without affecting the melt viscosity through the addition of mercaptopropyltriethoxysilane (MPTES) to the unsaturation within the polymer. Rapid hydrogen atom donation by thiols underlies this unique selectivity for grafting versus molecular weight alteration, and gives rise to a remarkable tolerance of MPTES additions to phenolic antioxidants. Direct comparisons of the moisture‐curing efficiencies provided by the two functionalization techniques reveal few significant differences in crosslink yields or composition distributions. POLYM. ENG. SCI., 46:480–485, 2006. © 2006 Society of Plastics Engineers. 相似文献
87.
An analysis for steady-state heat transfer between an underground vertical infinite cylindrical structure and ground is presented, and is used as a direct method to evaluate conduction shape factor for the structure. Numerical values of the shape factor have been determined after solving the transcendental equation involved here, subject to some valid approximation, and found to converge to a finite value. The convergence has also been verified by studying the numerical values of the shape factor for different length:radius ratio of the cylindrical structure and the result is convincing. 相似文献
88.
The determination of flutter frequencies and flutter boundary pressures of conical shells is carried out using finite element analysis. Static condensation procedure with Q.R. algorithm is used for the extraction of eigen values of the system. An empirical relation for determining the values of flutter boundary pressures of clamped-clamped conical shells is proposed. It is seen that there is an optimum semivertex angle at which a given conical shell of prescribed length and initial radius offers maximum resistance for flutter. 相似文献
89.
A. Sengupta Chandana Sengupta U. K. Mazumder 《European Journal of Lipid Science and Technology》1987,89(3):119-123
Fatty acid compositions of four lipid fractions of Celastrus paniculatus seed namely normal triglycerides (20.2%), polar triglycerides (44.4%), polar nonglyceridic ester (23.5%), and nonpolar nonglyceridic ester (11.9%), have been determined by gas liquid chromatography. Percentage contents of major component acids in these fractions are: palmitic, 25.1, 42.0, 12.7, 58.2; stearic, 6.7, 4.5, 15.8; oleic, 46.1, 24.8, 4.7, 14.2; linoleic, 15.4, 14.7, 10.0; and linolenic, 3.0, 13.1, 43.0, respectively. The major molecular species constituting the normal triglycerides are: palmitooleopalmitin, 6.8%; palmitooleostearin, 5.6%; palmitodiolein, 14.7; palmitooleolinolein, 7.0%; stearodiolein, 6.1%; triolein, 8.0% and dioleolinolein 7.6%. Lipolysis of the polar triglyceride indicated as high as 59.6% of saturated acids linked to the 2-position of glycerol. 相似文献
90.
Anupam Sengupta Sajal K. Roychoudhury 《Journal of the science of food and agriculture》1977,28(5):463-468
The fatty acid composition of Buchanania lanzan seed oil, determined by urea complex formation and gas liquid chromatography (g.l.c), was found to be: myristic, 0.6; palmitic, 33.4; stearic, 6.3; oleic, 53.7; and linoleic, 6.0%. Triglyceride compositions of the native seed oil and its randomised product were calculated from the fatty acid compositions of the triglycerides and of the corresponding 2-monoglycerides produced by pancreatic lipase hydrolysis. The oil is composed of 3.2, 35.8, 45.5 and 15.5% trisaturated, monounsaturated disaturated, diunsaturated monosaturated and triunsaturated glycerides respectively. The special characteristic of the B. lanzan seed oil is its content of 22.7, 31.0 and 11.3% dipalmitoolein, dioleopalmitin and triolein respectively. The percent GS3 content in the oil increased from 3.2 to 7.5 by the process of randomisation. On directed interesterification the oil yielded a product with a slip point of 41.5°C which may be suitable as a coating material for delayed action tablets. The oil also appears to be a promising one as a commercial source of palmitic and oleic acids. 相似文献