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In small quantity cooling lubrication (SQCL) grinding, small quantity of cutting fluid is air-atomized to serve the purpose of cooling and lubrication during the process. As the flow rate of cutting fluid is intended to be set as low as possible, it is essential to develop high performance cutting fluids. In the present work, it has been attempted to enhance cooling-lubrication and wetting characteristics of a bio-degradable flower seed extracted oil, namely sunflower oil, with suspension of multi-walled carbon nano tubes (MWCNT). The suspension was realized by ultrasonic agitation provided through a 700 W probe sonicator. This new generation fluid was used as a cutting fluid in small quantity cooling-lubrication (SQCL) mode; for grinding hardened AISI52100 steel by a vitrified bonded alumina wheel. Thermal conductivity, anti-frictional properties and therefore the cooling-lubrication characteristics of sunflower oil could be enhanced significantly by the dispersion of nanoparticles. Similarly, wettability of the ordinary sunflower oil was substantially improved with nano-suspension. Augmentation of its overall quality by such nano particle suspension subsequently led to remarkable reduction in requirement of specific energy in the grinding process, as compared with the values obtained by using ordinary sunflower oil (SQCL mode) and soluble oil (delivered in conventional flood and SQCL mode). The wear rate of wheel was also significantly minimized and F t /F n ratio could be kept at steady and lower level, which depict the better sharpness retention of grits under nano-SQCL environment. Surface quality was superior under the nano-SQCL environment. Compressive residual stress could be achieved on the ground surface along with acceptable surface roughness. [ABSTRACT FROM AUTHOR]

The use of high-frequency millimeter wave (mmWave) bands for 5G communication systems has received much attention over the last few years. Analog-to-digital converters (ADCs) contribute significantly to the implementation cost and power consumption of wireless receivers. The use of large antenna arrays in mmWave communications causes these costs to rise even further. Using low precision quantizers in ADCs can reduce these costs significantly. In this paper, we propose a novel receiver design using low precision quantizers drawing ideas from the parallel ADC design literature. Utilizing structural similarities between multi-antenna receivers and parallel ADCs, we show that the signal-to-noise ratio and achievable rate, respectively, scale linearly and logarithmically with the number of antennas. We also extend the idea to the scenario where multiple streams can be transmitted simultaneously. Our simulations of the receiver show promising bit error rate performance under different scenarios and also show how error control coding can be incorporated to improve performance. All our designs depend only on symbol rate sampling, which eliminates costly oversampling of high bandwidth signals. [ABSTRACT FROM PUBLISHER]

Silk obtained from silkworm, Bombyx mori L., is considered as the only natural animal fiber and the insect depends only on the mulberry leaves at their larval stage. We have isolated and purified low molecular weight (LMW, 0.5-3 KDa) peptide(s) from mulberry leaves (SI cultivar). For peptide isolation, leaves of three maturity stages (young, mature and senescence) were selected on the basis of biochemical and morphological attributes of leaves. Feeding of mulberry leaves supplemented with isolated peptide(s) from 5th instar larval stage resulted in rapid larval growth and enhanced cocoon shell weight, when compared with control. Highest larval growth rate and cocoon weight was obtained from peptide treatment isolated from young leaves. Scanning electron microscopic study (SEM) revealed that the silk fibers obtained from peptide treated silkworm were smooth in texture and at least two times thicker than untreated counterparts. HPLC analysis indicated that the major peptide peak at mature stages of mulberry leaves was partially fragmented during senescence. Sequence analysis of bioactive peptide revealed the abundance of aromatic and hydrophobic amino acids with antioxidant activity anu exhibits striking similarity with molting hormone Bombyxin. Therefore the peptides isolated from mulberry leaves might have an implication in improving sericulture and textile industry. [ABSTRACT FROM AUTHOR]

Beneficial effects of liquid nitrogen (LN 2 ) as a metal working fluid (MWF) in high speed machining applications are well recognized. However, adequate attention is not given on possible deleterious effects because of its extremely low boiling point. In the present work, an in-depth investigation has been carried out to explore pros and cons of LN 2 application when a vitrified bonded Al 2 O 3 wheel was used for grinding hardened AISI 52100 steel. It was observed that LN 2 application in place of soluble oil could substantially enhance G-ratio. Although, this observation is in agreement with the reported literatures, the other findings contradicted the notion that cryogenic application is favorable for grinding. Unlike under soluble oil environment, the vitrified bonded wheel failed to produce a good finish when LN 2 was used. There were evidentially more number of microscopic zones having smeared, re-deposited chips and micro-folded ridges on ground surface. Interestingly, larger wear flat areas on wheel topography were observed under LN 2 environment. When critically investigated, it was found that its extremely low temperature unfavorably strengthened bond, which led to undesirable retention of progressively wearing grits. Such an unfavorable alteration in wheel topography led to higher power consumption in the process. Additionally, ground specimen suffered from higher dimensional inaccuracy. Microscopic morphology of chips indicated prevalence of low temperature in the vicinity of grinding zone under this environment but interestingly the ground specimen experienced unfavorably more tensile residual stress with LN 2 than with soluble oil. [ABSTRACT FROM AUTHOR]

Objective: Buccoadhesive wafer dosage form containing Loratadine is formulated utilizing Formulation by Design (FbD) approach incorporating sodium alginate and lactose monohydrate as independent variable employing solvent casting method. Methods: The wafers were statistically optimized using Response Surface Methodology (RSM) and Artificial Neural Network algorithm (ANN) for predicting physicochemical and physico-mechanical properties of the wafers as responses. Morphologically wafers were tested using SEM. Quick disintegration of the samples was examined employing Optical Contact Angle (OCA). Results: The comparison of the predictability of RSM and ANN showed a high prognostic capacity of RSM model over ANN model in forecasting mechanical and physicochemical properties of the wafers. Thein vivoassessment of the optimized buccoadhesive wafer exhibits marked increase in bioavailability justifying the administration of Loratadine through buccal route, bypassing hepatic first pass metabolism. [ABSTRACT FROM AUTHOR]