Performance analysis of hybrid/single nanofluids on augmentation of heat transport in lid-driven undulated cavity

This numerical study reveals the heat transfer performance of hybrid/single nanofluids inside a lid-driven sinusoidal trapezoidal-shaped enclosure. The right and left inclined surfaces of the trapezium have been considered as insulated, whereas the bottom sinusoidal wavy and the flat top surfaces of the enclosure as hot and cold, respectively. The governing partial differential equations of fluid's velocity and temperature have been resolved by applying the finite element method. The implications of Prandtl number (4.2-6.2), Richardson number (0.1-10.0), undulation number (0-3), nanoparticles volume fraction (0%-3%), and nanofluid/base fluid (water, water–copper (Cu), water–Cu–carbon nanotube, water–Cu–copper oxide (CuO), water–Cu–TiO₂, and water–Cu–Al₂O₃) on the velocity and temperature profiles have been studied. Simulated findings have been represented by means of streamlines, isothermal lines, and average Nusselt number of above-mentioned hybrid nanofluids for varying the governing parameters. The comparison of heat transfer rates using hybrid nanofluids and pure water has been also shown. The heat transfer rate is increased about 15% for varying Richardson number from 0.1 to 10.0. Blending of two nanoparticles suspension in base fluid has a higher heat transfer rate—approximately 5% than a mononanoparticle. Moreover, a higher average Nusselt number is obtained by 14.7% using the wavy surface than the flat surface of the enclosure. Thus, this study showed that applying hybrid nanofluid may be beneficial to obtain expected thermal performance.     

Development of medical cotton fabrics with Punica granatum L extract finishing for nosocomial infections control

Transmission of pathogenic microorganisms on textile in the hospital settings may contribute to nosocomial infection. This study was aimed to develop a natural antimicrobial finishing on textile that can prevent transmission of pathogenic microorganisms that meets American Association of Textiles Chemists and Colorists (AATCC) standard. Punica granatum L ethanolic extract was shown to have broad spectrum antimicrobial efficacy with bis(6-methylheptyl)-benzene-1,2-dicarboxylate and ethyl-pentadecanoate as the main bioactive constituents. Textile samples developed with the extract finishing exhibited excellent antimicrobial efficacy with a growth reduction of 99.9% on Hoheinstein Challenge Test. The wash durability of the finished textile was found good even after 30 washes with commercial detergent.     

Fabrication of innovative charkha for pashmina spinning and its impact assessment

Pashmina, a finest natural animal fiber is utilized for preparation of world famous Kashmiri pashmina shawls by traditional practices. Hand spinning is one of the important processing step, wherein fibers are converted into a fine yarn on a traditional spinning wheel (yander). The task is usually carried out by women folk. It is a laborious process resulting in a lot of physical stress affecting the efficiency of artisans. An innovative charkha has been fabricated to reduce the physical stress and its effect on the spinning efficiency and remuneration of artisans over traditional one was evaluated. The study revealed that innovative charkha was efficient in terms of time consumed for spinning by 73.50% over traditional one besides decreasing physical drudgery. In terms of income, there was an increase of 146% over traditional one for same period of time without deteriorating the quality of yarn.     

An absolute measure for stereoblock and heterotactic polymers

Summary A criterion (°) for testing stereoblock and heterotactic polymers is developed. The criterion takes values between 1 and-1, a value of 1 is indicative of a pure stereoblock polymer and a value of-1 indicates a pure heterotactic polymer. The criterion (°) is compared with persistence ratio (ρ) and average stereochemical sequence length. The importance of δ as an aid in the synthesis of stereoblock polymers is discussed.     

Photochemical reactions of polyene sequences produced during the degradation of poly(vinyl chloride)

Photosensitized reactions of tetrahydrofuran (THF) and dichloromethane (DCM) solutions of polyene sequences introduced into poly(vinyl chloride) molecules by chemical degradation have been investigated. The distribution of polyenes produced following further thermal degradation in DCM were shifted toward longer sequences than were observed for the same reaction in THF. Benzophenone-sensitized bleaching of the polyene absorption in aerated THF solutions was characterized by induction periods, but the presence of oxygen had little effect on the same reaction in DCM. The bleaching process seems to involve reaction of the polyenes with the tetrahydrofuranyl radical formed by abstraction of the α-hydrogen from THF by triplet benzophenone. No induction periods were observed for benzoin-sensitized reactions, but the rate of reaction was faster in DCM than in THF. The differences are discussed in terms of the difference in reactivity of the alkyl and alkoxy radicals.     

Comb polysiloxanes with ω-hydroxyoligo(oxyethylene) side chains

Summary Comb-like polysiloxanes with pendant chains of the type (CH₂)₃(OCH₂ CH₂)_nOH (n=0, 8 or 15) were synthesized by hydrosilylation of poly(methylsiloxane) with the corresponding monoallyl glycols in which the hydroxyl group was protected with tetrahydropyran. The polymers were characterized by¹H and²⁹Si NMR, and by GPC and DSC. A considerable fraction of small cycles is formed for the n=o compound during the deprotection reaction. Side chain crystallization occurs but is slower than for polymers containing side chains with terminal methoxy groups.     

Instrumental texture and flavonoid profile of paste developed from sprouted onion varieties of Indian origin

The effect of sprouting on the instrumental texture, antioxidant activity, and ?avonoid pro?le of the paste prepared from four Indian onion varieties (Punjab White, Punjab Naroya, PRO-6, and Commercial) was studied. The significant (P ? 0.05) effect of sprouting on microstructure, firmness, adhesiveness, gumminess, and chewiness in paste samples from all varieties was observed. There was significant decrease (P ? 0.05) in lightness with consequent significant (P ? 0.05) increase in redness, greenness, and yellowness in paste samples which was due to the increase in anthocyanin content with sprouting. The paste samples from sprouted onion varieties also showed an increase in phenol content, flavonoid content, antioxidant capacity, and DPPH radical scavenging activity. The HPLC analysis revealed an increase in total flavonoids in pastes from PRO-6 and Punjab Naroya varieties. Thus, present study implied that sprouting could be beneficial as it enhanced the functional potential of onion pastes.     

Visual search analysis using parametric fixations

Multimedia Tools and Applications - Eye movement analysis has been an important area of research. The analysis of eye movements could help in better understanding of human preferences, behavioral...