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11.
Suniti Misra Mrinal K. Ghosh A. Choudhury Ashis K. Dutta Prasanta K. Pal Amitabha Ghosh 《Journal of the science of food and agriculture》1985,36(11):1193-1196
Fatty acids of the total lipids of flesh and hepatopancreas of Macoma sp. have been determined. The level of 20:5w3 (ca 17%), a biologically important fatty acid, was found to be considerably high. Other major component fatty acids were 16:0, 16:1, 18:1 and 22:4w6. High levels of 22:5w6 (8%), 22:5w3 (8%) and 22:6w3 (ca 15%) were found in flesh lipid. Nonsaponifiables were also high (28–30%). Alkyl ether acyl glycerols were found in flesh (1.3%) and hepatopancreas (3.8%). 相似文献
12.
Ozone exposure results in an acute decrease in the serum levels of thyroid hormones; the physiologic sequelae of this are unclear. Whereas thyroid hormone supplementation appears to benefit pulmonary function in septic, oxyradical models of injury, thyroid hormone increases ozone toxicity. We demonstrated an increase in metabolic rate and pulmonary injury in lungs from ozone exposed, T3 treated animals. This was evidenced by an increase in pulmonary weight gain, vascular perfusion pressure, and decrease in compliance in the supplemented animals. However, an increase in alkane generation, as an index of lipid peroxidation, was not seen in the ozone exposed, hormonally treated animals. This suggests that although thyroid hormone supplementation increases metabolic rate and ozone toxicity, an increased rate of lipid peroxidation plays a minimal role. 相似文献
13.
14.
In the research presented here, we explore the use of a low‐energy plasma to deposit thin silicone polymer films using tetramethyldisiloxane (TMDSO) (H(CH3)2? Si? O? Si? (CH3)2H) on the surface of an ethylene propylene diene elastomeric terpolymer (EPDM) in order to enhance the surface hydrophobicity, lower the surface energy and improve the degradation/wear characteristics. The processing conditions were varied over a wide range of treatment times and discharge powers to control the physical characteristics, thickness, morphology and chemical structure of the plasma polymer films. Scanning electron microscopy (SEM) shows that pore‐free homogeneous plasma polymer thin films of granular microstructure composed of small grains are formed and that the morphology of the granular structure depends on the plasma processing conditions, such as plasma power and time of deposition. The thicknesses of the coatings were determined using SEM, which confirmed that the thicknesses of the deposited plasma‐polymer films could be precisely controlled by the plasma parameters. The kinetics of plasma‐polymer film deposition were also evaluated. Contact angle measurements of different solvent droplets on the coatings were used to calculate the surface energies of the coatings. These coatings appeared to be hydrophobic and had low surface energies. X‐ray photoelectron spectroscopy (XPS) and photoacoustic Fourier‐transform infrared (PA‐FT‐IR) spectroscopy were used to investigate the detailed chemical structures of the deposited films. The optimum plasma processing conditions to achieve the desired thin plasma polymer coatings are discussed in the light of the chemistry that takes place at the interfaces. Copyright © 2004 Society of Chemical Industry 相似文献
15.
Approximations commonly used to determine the effective indexes of the guided modes of optical waveguides formed using multiple quantum well (MQW) materials are compared to the exact solutions in the slab waveguide model. Modeling the quantum well region as a single homogeneous layer with an average index of refraction is shown to produce results in close agreement with exact values of the effective index. A geometrically weighted average of the indexes provides the most accurate approximation for typical values of index and layer thickness of GaAs-AlxGa1-xAs quantum well waveguides 相似文献
16.
Undoped and Te-doped gallium antimonide (GaSb) layers have been grown on GaSb bulk substrates by the liquid phase epitaxial
technique from Ga-rich and Sb-rich melts. The nucleation morphology of the grown layers has been studied as a function of
growth temperature and substrate orientation. MOS structures have been fabricated on the epilayers to evaluate the native
defect content in the grown layers from theC-V characteristics. Layers grown from antimony rich melts always exhibitp-type conductivity. In contrast, a type conversion fromp- ton- was observed in layers grown from gallium rich melts below 400 C. The electron mobility of undopedn-type layers grown from Ga-rich melts and tellurium doped layers grown from Sb- and Ga-rich solutions has been evaluated.
Paper presented at the poster session of MRSI AGM VI. Kharagpur. 1995 相似文献
17.
B. K. Dutta 《Acta Mechanica》1989,78(3-4):255-262
Summary The conjugate problem of heat transfer from an accelerating surface in presence of suction and blowing has been solved analytically. The effects of different parameters on cooling of the surface have been discussed.With 3 Figures 相似文献
18.
Strain compensated InGaAs-GaAsP-InGaP laser 总被引:1,自引:0,他引:1
N.K. Dutta W.S. Hobson D. Vakhshoori H. Han P.N. Freeman J.F. de Jong J. Lopata 《Photonics Technology Letters, IEEE》1996,8(7):852-854
The performance characteristics of InGaAs-GaAsP-InGaP strain compensated laser emitting near 1 /spl mu/m are reported. The ridge waveguide lasers have room temperature threshold current of 18 mA and differential quantum efficiency of 0.45 W/A/facet. The linewidth enhancement factor is smaller and gain coefficient is larger for these strain compensated lasers compared to that for conventional strained layer laser. This may be due to higher effective compressive strain in the light emitting layer of these devices which reduces the effective mass. The observed larger gain coefficient is consistent with the measured larger relaxation oscillation frequency of these lasers compared to that for a conventional strained layer laser. 相似文献
19.
Sinha Swati Shaw Siddharth Biswas Kunal De Debashis Das Samir Chandra Sarkar Angsuman Bandyopadhyay Jaya 《Microsystem Technologies》2021,27(11):4087-4100
Microsystem Technologies - Single-Walled Carbon Nanotubes (SWCNTs) are widely used as potential carriers in drug delivery systems. The objective of this work was to observe the effects of pristine,... 相似文献
20.
Paresh Chandra Dutta 《Journal of the American Oil Chemists' Society》1997,74(6):659-666
Hydrogenated rapeseed oil/palm oil blend, sunflower oil and high-oleic sunflower oil, and French fries fried in these oils
were assessed for contents of sterol oxidation products. Different oxidation products of phytosterols (7α- and 7β-hydroxy-sito-and
campesterol, 7-ketosito- and 7-ketocampesterol, 5α,6α-epoxy-sito- and campesterol, 5β,6β-epoxy-sito-and campesterol, dihydroxysitosterol
and dihydroxycampesterol) were identified and quantiated by gas chromatography (GC) and GC-mass spectroscopy. Rapeseed oil/palm
oil blend contained 41 ppm total sterol oxides before frying operations. After two days of frying, this level was increased
to 60 ppm. Sunflower oil and high-oleic sunflower oil had 40 and 46 ppm sterol oxides, respectively, before frying operations.
After two days of frying operations, these levels increased to 57 and 56 ppm, respectively. In addition to campesterol and
sitosterol oxidation products, small amounts of 7α- and 7β-hydroxystigmasterol were detected in the oil samples. Total sterol
oxides in the lipids of French fries fried at 200°C in rapeseed oil/palm oil blend, sunflower oil, and high-oleic sunflower
oil were 32, 37, and 54 ppm, respectively. The levels of total oxidized sterols, calculated per g sample, ranged from 2.4
to 4.0 ppm. In addition to the content of phytosterol oxides, full scan mass spectra of several oxidation products of stigmasterol
are reported for the first time.
Part of these results were presented at the 86th Annual Meeting of the AOCS, May 7–11, 1995, San Antonio, TX. 相似文献