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61.
In this paper, we introduce a two-stage method to solve rectangular linear systems that exhibits faster convergence than typical stationary iterative methods. Under suitable conditions, we prove convergence of the new method. The number of outer iterations can be reduced by using a few significant number of inner iterations for efficient computations. Further, we perform a comparison analysis, and establish that a higher number of inner iterations ensures a smaller spectral radius of the global iteration matrix. We also discuss the uniqueness of a proper splitting, and illustrate different comparison theorems for different subclasses of proper splittings. 相似文献
62.
N. K. Mishra 《腐蚀工程科学与技术》2014,49(8):705-711
Failure of components due to high temperature oxidation is the major degradation mechanism in boiler and gas turbine industries. Superalloys having superior mechanical properties and creep resistance are used in these applications but lack resistance to oxidation under aggressive environments. Protective coatings are used to improve their oxidation resistance in such applications. In the present investigation, Al2O3–40%TiO2 coating was deposited on superni 718 and superni 601 superalloys by low velocity oxy fuel process. The as sprayed coating was characterised for microhardness, surface roughness, scanning electron microscopy and X-ray diffraction analysis. High temperature oxidation behaviour of Al2O3–40%TiO2 coated and uncoated superni 718 and superni 601 superalloys has been evaluated at the elevated temperatures of 800 and 900°C for total duration of 50 cycles under cyclic conditions. Each cycle consisted of keeping the samples for 1 h at the elevated temperature followed by 20 min cooling in ambient air. Al2O3–40TiO2 coating in the as sprayed condition showed the presence of Al2O3–TiO2, α-Al2O3, TiO2 as the main phases. Al2O3–40%TiO2 coating on superni 718 and superni 601 superalloys has shown a lower oxidation rate as compared to those of uncoated superalloys. However, the oxidation rate of the coating was not steady due to the occurrence of spallation/sputtering at various stages. The coating was found adherent on the substrate superalloys throughout the study. 相似文献
63.
Singh Chitranjan Prasad Agrawal Hemant Mishra Arvind Kumar 《Bulletin of Engineering Geology and the Environment》2021,80(10):8009-8019
Bulletin of Engineering Geology and the Environment - Vibrations induced due to blasting in mines may damage the nearby houses and disturb the habitants. The monitoring, prediction, and control of... 相似文献
64.
Mishra Shraddha Singh Surya Prakash 《Clean Technologies and Environmental Policy》2019,21(6):1237-1257
Clean Technologies and Environmental Policy - There is a growing consensus that the increase in greenhouse gases results in unfavorable changes to the Earth’s climate and is responsible for... 相似文献
65.
Physico‐mechanical properties of nano‐polystyrene‐decorated graphene oxide–epoxy composites 下载免费PDF全文
Prashant S Khobragade Dharmesh P Hansora Jitendra B Naik James Njuguna Satyendra Mishra 《Polymer International》2017,66(10):1402-1409
Nano‐polystyrene (nPS)‐decorated graphene oxide (GO) hybrid nanostructures were successfully synthesized using stepwise microemulsion polymerization, and characterized using Fourier transform infrared (FTIR) spectroscopy, X‐ray diffraction (XRD), field‐emission scanning electron microscopy and transmission electron microscopy. XRD and FTIR spectra revealed the existence of a strong interaction between nPS and GO, which implied that the polymer chains were successfully grafted onto the surface of the GO. The nPS‐decorated GO hybrid nanostructures were compounded with epoxy using a hand lay‐up technique, and the effect of the nPS‐decorated GO on the mechanical, thermal and surface morphological properties of the epoxy matrix was investigated using a universal tensile machine, Izod impact tester, thermogravimetric analysis and contact angle measurements with a goniometer. It was observed that in the epoxy matrix, GO improved the compatibility. © 2017 Society of Chemical Industry 相似文献
66.
The procedure for the determination of satellite nadir and azimuth angles has beenverifiedusing the Coastal Zone Color Scanner (CZCS) geolocation algorithm formulated by Wilson and co-workers in 1981. The error involved in the determination of satellite nadir and azimuth angles for positive and negative tilt of the mirror using the above method is discussed. A simple method to determine nadir and azimuth angles for a tilting mirror is proposed. The nadir and azimuth angles after roll, pitch and yaw of the satellite are presented. 相似文献
67.
68.
Effect of relative humidity and light conditions on the oxidative stability of sunflower oil blends stabilised with synthetic and natural antioxidants 下载免费PDF全文
Rohit Upadhyay Hari Niwas Mishra 《International Journal of Food Science & Technology》2016,51(2):293-299
The effect of relative humidity (RH) and light conditions on the oxidative stability of sunflower oil (SO) stabilised with oleoresin rosemary + ascorbyl palmitate (SOR), sage + ascorbyl palmitate (SOS) and tertiary butyl hydroquinone (SOT) was investigated. The SO without additive (SOC) served as positive control. Oil samples were subjected to 3 RH (29%, 52% and 75%) and two light conditions (dark, D and fluorescent light (600 lx), L) at 60 °C for 7 days. The oxidative stability was monitored by peroxide value (PV), conjugated diene value (CDV), free fatty acids (FFAs) and Rancimat induction period (IP). A direct relationship was noted between RH and increase in PV, CDV and FFA levels irrespective of light conditions. The detrimental effect of light on the oxidative stability was prominently noted at higher RH (75%) which followed an order: SOC > SOT > SOR > SOS. The samples stored under lower RH (29% and 52%), and dark conditions were better stabilised than light‐exposed counterparts. 相似文献
69.
Pratyush Kumar Mishra Chang-Mo Yoo Dr. Eunmi Hong Prof. Dr. Hyun Woo Rhee 《Chembiochem : a European journal of chemical biology》2020,21(7):924-932
Studying protein–protein interactions (PPIs) is useful for understanding cellular functions and mechanisms. Evaluating these PPIs under conditions as similar as possible to native conditions can be achieved using photo-crosslinking methods because of their on-demand ability to generate reactive species in situ by irradiation with UV light. Various fusion tag, metabolic incorporation, and amber codon suppression approaches using various crosslinkers containing aryl azide, benzophenone, and diazirines have been applied in live cells. Mass spectrometry and immunological techniques are used to identify crosslinked proteins based on their capture transient and context-dependent interactions. Herein we discuss various incorporation methods and crosslinkers that have been used for interactome mapping in live cells. 相似文献
70.