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Tribological components cost just a fraction of the whole spacecraft, but they often lead to failures that partially or completely disrupt the spacecraft. Mechanical components used in space applications have to withstand extreme and severe environmental conditions such as very high or very low cryogenic temperatures, high vacuum, corrosive elements and radiation. MoS2 is the most widely used lubricating material in space applications. It possesses a lamellar structure with strong covalent bonds within layers and simultaneously weak van der Wall’s interlayer bonds, resulting in easy shearing of the crystals in the direction parallel to the basal planes, hence acting as a good solid lubricant. In this research, a thin film nano scale coating of MoS2 was deposited on steel using Physical Vapour Deposition (PVD). The PVD technique used was the RF magnetron sputtering process. Material characterization was performed using X-Ray diffraction (XRD), Field Emission Scanning Electron Microscopy (FESEM) and Raman spectroscopy. According to the results, the developed MoS2 nano coatings have a polycrystalline structure with basal planes that are oriented perpendicular to the substrate surface.

The lubrication effect of solid-based materials has been recognized for centuries, but their use as lubricants dates back to only about 50 years. Solid lubricants are used in applications where parts operate under severe operating conditions such as extreme temperatures and very high vacuum. Solid lubricants replace liquid based lubricants for operation under extreme environmental conditions that are beyond the capability of a liquid-based lubricant such as high or very high vacuum, high and cryogenic temperatures, radiation, corrosive gases, and fretting wear. Applications such as space mechanisms, satellites, space vehicles, turbopumps, nuclear reactors, refrigeration plants, etc are examples of such operating conditions. In this research, nano scale composite coatings of MoS2with varied proportions of ZrN (5%, 10% and 20%) were deposited on Ti3SiC2 Max phase substrate using Physical Vapour Deposition (PVD). The PVD technique used was the RF magnetron sputtering process. Material characterization was carried out using Field Emission Scanning Electron Microscope (FESEM) Spectroscopy and Energy Dispersive X-Ray Spectroscopy (EDS). Addition of ZrNis observed to reduce the porosity of the self-lubricating MoS2 coating.

Ascariasis is highly endemic in Kashmir valley as temperate climate and wet soil provide excellent conditions for its development. We studied 198 cases (11%) of biliary ascariasis out of 1,800 patients of worm infestation from December 2001 to December 2004 in the age group of 4-15 years. In our study, we found biliary ascariasis to be more common in female children, and most common clinical presentation was biliary colic in 143 patients, cholangitis in 28, cholecystitis in 15, liver abscess 7, pancreatitis 4 and postoperative worm infestation in 1 patient. Ultrasonography of abdomen was the diagnostic tool of choice with hundred percent results. Most of the patients were managed conservatively. ERCP was not done in children because of need of general anesthesia and difficulty in performing the procedure. Surgical intervention was required in 23 patients (cholecystectomy with CBD exploration in 5, choledochotomy alone in 13, drainage of liver abscess in 3, choledochoduodenostomy in 1 and peritoneal lavage in 1).

The combining ability provides insightful information about the genetic mechanisms that govern the inheritance of traits and enables the identification of potential inbred lines; and promising hybrid combinations for crop improvement. However, most studies on quality protein maize (QPM) have focused on nutritional aspects, and very few are focused on their combining ability. In addition, studies on the adaptation, hybrid performance and stability of QPM in temperate areas remain scarce. Therefore, the present study sought to examine the combining ability of eight QPM inbred lines (QPM13, QPM14, QPM20, QPM21, QPM49, QPM50, VQL1, and VQL17). These 8 lines were subjected to half-diallel mating. Consequently, 28 crosses obtained were further evaluated in the temperate region of Kashmir against one check and parents in the RCBD, with three replications in a single row. The results revealed significant variances for general combining ability (GCA) and specific combining ability (SCA) for most of the recorded agronomic, yield, and quality traits. The crosses QPM49 × VQL1, QPM 13 × QPM14, QPM21 × VQL17, QPM13 × QPM50 and QPM50 × VQL17 were found to perform best in terms of earliness in tasselling (-1.842), silking (-1.204), days to mature (-2.654), highest yield (12.875 g)and protein content (1.113%), respectively. These promising crosses can be viable material sources for future QPM variety development programs in temperate regions. [ABSTRACT FROM AUTHOR]

The two significant challenges facing the world are growing pollution issues and fossil fuel depletion. Emissions emanating and consumption of fossil fuels in diesel engines are reduced by modifying engine operating parameters and by developing more efficient alternative fuels. In view of this, the current work evaluates the effect of ZnO nanoparticles mixed with diesel-ethanol blend on the working characteristics of diesel engine at different CR's and loads. The test fuels selected for the experimental work are pure diesel, DE10, DE10ZnO50 and DE10ZnO100, and the compression ratios are 16.5, 17.5 and 18.5. Using ultrasonic agitation, ZnO nanoparticles were incorporated in fuel blends in the presence of 2% surfactant span80. All fuel blends were tested for their physicochemical properties, and it was noted that the fuel properties improved when ZnO nanoparticles were added to the test blends. The results showed that at CR 18.5, the DE10ZnO100 fuel blend shown maximum improvement in engine working characteristics as compared to other blends. In comparison to diesel at CR 18.5 for DE10ZnO100 blend, BTE enhanced by 5.73% and BSFC was reduced by 8.31%. CO, NOx and UHC emissions are reduced by 21.96%, 6.41% and 12.07%, whereas CO2 emissions have increased by 7.44%, respectively. Different concentration of ZnO nanoparticles incorporated diesel-ethanol blend is prepared. The effect of ZnO nanoparticles diesel-ethanol blend at various compression ratios of diesel engine was investigated Optimal results are noted for the DE10ZnO100 blend at compression ratio 18.5. Improvements in BTE and BSFC is 5.73% and 8.31% as compared to diesel at CR 18.5 for DE10ZnO100 blend. CO, UHC and NOx reduced by 21.96%, 12.07% and 6.41%. [ABSTRACT FROM AUTHOR]