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111.
Narottam Sutradhar Apurba Sinhamahapatra Biplab Roy Hari C. Bajaj Indrajit Mukhopadhyay Asit Baran Panda 《Materials Research Bulletin》2011,46(11):2163-2167
MgO nano-rods of several microns in length and 50–100 nm in width were prepared by calcining nesquehonite phase, obtained by simple precipitation using (NH4)2CO3 under ambient condition. The MgO nano-rod with reasonably high surface area (75–120 m2 g−1) exhibits strong activity in solvent-free base catalyzed Claisen-Schmidt condensation giving 99% conversion in 2 h and is easily recyclable with no significant change in catalytic activity. Presence of numerous basic sites of different strengths (surface hydroxyl groups, low coordinate O2− sites) is attributed to the observed effect. 相似文献
112.
J. Portal C. Carrot J.C. Majeste S. Cocard V. Pelissier K. Baran I. Anselme‐Bertrand 《Polymer Engineering and Science》2008,48(6):1068-1076
The aim of this work is to develop a set of experimental methods to investigate the morphology of blends of two immiscible elastomers, namely natural rubber (NR) and polybutadiene (PB). Selective extraction, dynamic mechanical spectroscopy in the melt, and transmission electron microscopy (TEM) were used to get information on the structure of unfilled and uncured blends. 1,2‐dichloroethane and 4‐methyl‐2‐pentanone (MIBK) were employed to dissolve selectively NR and PB in specific conditions to assess the continuity of the phases. In oscillatory shear flow at low frequencies and low volume fractions of the minor phase, the storage modulus shows an excess of elasticity that increases with the dispersed phase content. At higher concentration of the minor phase, the elasticity decreases in relation to the morphology. Samples were also ultra cryo‐microtomed and then analyzed by TEM. The superposition of the three methods highlights the existence of a phase‐inversion point for these systems. POLYM. ENG. SCI., 2008. © 2008 Society of Plastics Engineers 相似文献
113.
Pradhan Dristhi Baishya Himakshi Das Amit Baran 《Food science and biotechnology》2022,31(11):1443-1450
Food Science and Biotechnology - The study aimed to investigate the effects of various pretreatment methods on sohiong fruit juice during the microfiltration process. The ultrasound,... 相似文献
114.
Hikmet Cicek Ozlem Baran Mortaza Tahmasebian Yasar Totik Ihsan Efeoglu 《Journal of Adhesion Science and Technology》2013,27(12):1140-1148
TiBN coatings have high hardness and high adhesion. Due to these excellent properties there has been increasing interest in TiBN coatings. In this study, TiBN coatings were deposited on AISI D2 cold work tool steel and silicon wafers by closed field unbalanced magnetron sputtering (CFUBMS). The structural, mechanical and adhesion properties of these coatings were analysed by X-ray diffraction, scanning electron microscopy, microhardness test, indentation test and scratch tests. TiBN coatings produced by magnetron sputtering exhibited a dense and columnar structure. These results indicate that TiB2, TiN and h-BN exist in crystalline forms at all coatings. The highest hardness was obtained at the lowest nitrogen flow rate. Very few cracks were observed at the edge of the indentation marks at the highest nitrogen flow rate. The highest critical load obtained with scratch test was identified as 102?N. 相似文献
115.
Feridoon Azough Robert Freer Stephen R. Yeandel Jakub D. Baran Marco Molinari Stephen C. Parker Emmanuel Guilmeau Demie Kepaptsoglou Quentin Ramasse Andy Knox Duncan Gregory Douglas Paul Manosh Paul Andrea Montecucco Jonathan Siviter Paul Mullen Wenguan Li Guang Han Elena A. Man Hasan Baig Tapas Mallick Nazmi Sellami Gao Min Tracy Sweet 《Journal of Electronic Materials》2016,45(3):1894-1899
116.
L. V. Baran 《Inorganic Materials》2013,49(3):257-265
This paper reports a study of fullerite-Sn films containing 4, 6, 8, 10, 12, or 20 at % Sn grown by thermal evaporation in vacuum using a combined atomic-molecular flow. The influence of metal content and thermal annealing on the surface topography, structure, and elemental and phase compositions of the fullerite-Sn films has been studied by atomic force microscopy, X-ray and electron diffraction, scanning electron microscopy, and X-ray microanalysis. The results demonstrate that films grown by codeposition of Sn atoms and fullerene molecules on oxidized single-crystal silicon substrates have a granular structure. The phase composition of the fullerite-Sn films varies widely, depending on the percentage of Sn: from an intercalated structure to a mixed-phase composite containing a hexagonal fullerite phase, tetragonal Sn, and fullerite-like structures containing Sn nanoparticles. Thermal annealing of the fullerite-Sn films leads to the formation of a new phase. 相似文献
117.
Poly‐2‐[(4‐methylbenzylidene)amino]phenol: Investigation of thermal degradation and antimicrobial properties
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A new polyphenol (poly‐2‐[(4‐methylbenzylidene)amino]phenol) (P(2‐MBAP)) containing an azomethine group was synthesized by oxidative polycondensation reaction of 2‐[(4‐methylbenzylidene)amino]phenol (2‐MBAP) with NaOCl, H2O2, and O2 oxidants in an aqueous alkaline medium. The structures of 2‐MBAP and P(2‐MBAP) were characterized by UV‐vis, FT‐IR, and 1H NMR spectra. While the monomer decomposed completely up to 350°C and 57.2% of the polymer decomposed up to 1000°C. The thermal degradation of P(2‐MBAP) was also supported by the Thermo‐IR spectra recorded in the temperature range of 25–800°C. Electrical conductivity of the polymer was observed to increase 108 fold after doping with I2. Antimicrobial activities of the P(2‐MBAP) and 2‐MBAP against Sarcina lutea, Enterobacter aerogenes, Escherichia coli, Enterococcus feacalis, Klebsiella pneumoniae, Bacillus subtilis, Candida albicans, and Saccharomyces cerevisiae were also investigated. The number average molecular weight (Mn), weight average molecular weight (Mw) and polydispersity index (PDI) of the polymers were determined by gel permeation chromatography (GPC). © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 41758. 相似文献
118.
Ionomer covalent functionalization of single‐walled carbon nanotubes by radical polymerization of zirconium acrylate
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Sellamuthu N. Jaisankar Donna J. Nelson Ravi Kumar Asit Baran Mandal 《American Institute of Chemical Engineers》2014,60(3):820-828
A facile and efficient covalent functionalization of single‐walled carbon nanotubes (SWCNTs) via peroxide‐mediated free radical covalent attachment and polymerization of zirconium acrylate is reported. The resulting covalently functionalized SWCNTs exhibit improved solubility in organic solvents. The covalently functionalized SWCNTs are characterized by cross polarization magic angle spinning 13C NMR, differential scanning calorimetry, thermogravimetric analysis, x‐ray diffraction, Raman, and infrared spectroscopy. Infrared spectroscopy reveals that carboxylate groups of covalently attached ionomers chelate with zirconium ions and the participating carboxylate groups may be from different ionomer chains leading to cross‐linking the chains. The SWCNT topology, ionic clustering, and π‐electron clouds were explored by transmission electron microscopy. © 2014 American Institute of Chemical Engineers AIChE J, 60: 820–828, 2014 相似文献
119.
Microbial mediated dimerization of fattyacids of sunflower oil: An effective role of lipase and biosurfactant
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This study emphasizes microbial mediated transformation of sunflower oil to an adhesive product and characterization in detail. Marine bacterial isolates Bacillus (MTCC 5514), when grown in mineral medium, releases both hydrolytic enzymes and surface‐active components during the log phase of growth. When this species was grown in the presence of sunflower oil at an optimized concentration of 5% (w/v) under room temperature, enzymatic hydrolysis of oil proceeds with the release of fatty acids and glycerol. Further, on increasing the incubation period, the presence of surface‐active components, lipase and glycerol, influence the dimerization of the fatty acids, which further, transformed to a polymerized product sunflower oil‐based adhesive product with adhesive nature. Liquid chromatography‐mass spectrometry (electrospray ionization) analysis further authenticates the presence of dimeracids. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 40555. 相似文献
120.
Kazi Afzalur Rahman Anutosh Chakraborty Bidyut Baran Saha Kim Choon Ng 《International Journal of Heat and Mass Transfer》2012,55(4):565-573
This study presents the theoretical frameworks for the thermodynamic quantities namely the heat of adsorption, specific heat capacity, entropy, and enthalpy for the adsorption of methane onto various carbonaceous materials. The proposed theoretical frameworks are developed from the rigor of thermodynamic property surfaces of a single component adsorbate–adsorbent system and by incorporating the micropore filling theory approach, where the effect of adsorbed phase volume is considered. The abovementioned thermodynamic properties are quantitatively evaluated from the experimental uptake data for methane adsorption onto activated carbons such as Maxsorb III at temperatures ranging from 120 to 350 K and pressures up to 25 bar. Employing the proposed thermodynamic approaches, this paper shows the thermodynamic maps of the charge and discharge processes of adsorbed natural gas (ANG) storage system for understanding the behaviors of natural gas in ANG vessel. 相似文献