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81.
This paper presents a study of responsivity of InAs0·3Sb0·7 infrared detector. Thin films of InAs0·3Sb0·7 semiconducting compound were prepared by vacuum evaporation on glass and mica substrates held at 473° K under a pressure
of 10−6 torr with deposition rate of 20 A°/sec. The isothermal annealing process was employed to improve the quality of the films.
The responsivity variation with blackbody temperature (333° K to 673° K), detector temperature (80° K to 303° K) and frequency
(10 Hz to 10 kHz) was measured. The experimental set-up and the results are presented and discussed. 相似文献
82.
Betal Atanu Bera Jayanta Alam Mahfooz Gandi Appala Naidu Sahu Satyajit 《Journal of Computational Electronics》2022,21(1):227-234
Journal of Computational Electronics - The strain- and electric field-dependent electronic and optical properties of monolayer GaInS2 have been calculated using density functional... 相似文献
83.
Mallikarjuna A. Kumar N. Suresh Babu T. Anil Ramesh S. Naidu K. Chandra Babu 《Journal of Inorganic and Organometallic Polymers and Materials》2021,31(12):4512-4522
Journal of Inorganic and Organometallic Polymers and Materials - (1-x) (Al0.2La0.8TiO3)?+?(x) (BiZnFeO3) (x?=?0.2–0.8) [ALTBZFO] nanocomposites were synthesized via... 相似文献
84.
Tejraj M. Aminabhavi Lakshmi C. Shetty B. Vijaya Kumar Naidu Nadagouda N. Mallikarjuna Vanajakshi M. Hanchinal 《应用聚合物科学杂志》2004,94(3):1139-1150
Sorption, diffusion, and swelling characteristics of sodium alginate and its blend membranes with poly(vinyl alcohol) were investigated for water–acetic acid mixtures by using a gravimetric method at 30, 40, and 50°C. The membranes were characterized by X‐ray diffraction and Fourier transform infrared techniques. Concentration‐independent diffusion coefficients were obtained by applying Fick's relationship before completion of equilibrium sorption. Permeation coefficients were calculated from sorption and diffusion coefficients. Concentration profiles of liquids were computed considering the sheet geometry for the membrane by solving Fick's equation under suitable boundary conditions. Arrhenius activation parameters were computed for the transport processes. Experimental results and calculated quantities were discussed to understand membrane–solvent interactions. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 94: 1139–1150, 2004 相似文献
85.
BACKGROUND/AIMS: After liver transplantation for autoimmune hepatitis, the long-term results and the incidence of recurrence of primary disease are unknown. METHODS: In this retrospective study we reviewed the clinical course of 25 patients transplanted for autoimmune hepatitis and followed for a mean of 5.3 years (2-8.5 years). RESULTS: The actuarial 5-year patient and graft survival rates were 91% (+/-6%) and 83% (+/-8%). The actuarial 1-year rate of acute rejection was 50% (+/-10.2%), which was comparable to that of patients transplanted for primary biliary cirrhosis and primary sclerosing cholangitis. Autoantibodies persisted in 77% of patients, at a lower titer than before liver transplantation. Ten patients were excluded from the study of autoimmune hepatitis recurrence, one because of an early postoperative death and nine because of hepatitis C virus infection acquired before or after liver transplantation. In the remaining 15 patients, who were free of hepatitis C virus infection, 5-year patient and graft survivals were 100% and 87%, respectively. Despite triple immunosuppressive therapy, three patients (20%) developed chronic hepatitis with histological and serological features of autoimmune hepatitis in the absence of any other identifiable cause. The disease was severe in two patients, leading to graft failure and asymptomatic in another, despite marked histological abnormalities. In one of these three patients, autoimmune hepatitis recurred on the second liver graft as well. CONCLUSIONS: Patients undergoing liver transplantation for autoimmune hepatitis have an excellent survival rate although severe primary disease may recur, suggesting the need for stronger post-operative immunosuppressive therapy. 相似文献
86.
MH Skiadopoulos S Surman JM Tatem M Paschalis SL Wu SA Udem AP Durbin PL Collins BR Murphy 《Canadian Metallurgical Quarterly》1999,73(2):1374-1381
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The Fraunhoffer diffraction analysis of cloud-covered satelite imagery has shown that the diffraction pattern follows approximately cosine squared distribution. The overshooting tops of clouds and the shadows cast by them contribute much to the diffraction of light, particularly in the high-frequency range. Indeed, cloud-covered imagery can be distinguished from cloud-free imagery on the basis of rate of decay of the diffracted light power in the high-frequency band. 相似文献