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1.
New mesogenic homologous series having an azo central linkage was synthesized by fixing a rigid 4-methyl phenyl azo group
to resorcinol moiety. The terminal and lateral phenolic -OH groups were esterified, one by one, with 4-n-alkoxybenzoyl and acetyl group, respectively. All the twelve homologues synthesized exhibit mesomorphism. The methoxy ton-decyloxy andn-hexadecyloxy derivatives exhibit monotropic nematic mesophase whereas,n-dodecyloxy andn-tetradecyloxy derivatives exhibit enantiotropic nematic mesophase. The mesogenic properties of the present series was compared
with those of other structurally related mesogenic series.
Paper presented at the 5th National Seminar on Liquid Crystals, University of Jammu, Jammu, December 1997. 相似文献
2.
Kaushik Patel Jagdish Prajapati Rajiv Vaidya S. G. Patel 《Bulletin of Materials Science》2005,28(5):405-410
Single crystals of the lamellar compound, ZrSe3, were grown by chemical vapour transport technique using iodine as a transporting agent. The grown crystals were characterized
with the help of energy dispersive analysis by X-ray (EDAX), which gave confirmation about the stoichiometry. The optical
band gap measurement of as grown crystals was carried out with the help of optical absorption spectra in the range 700–1450
nm. The indirect as well as direct band gap of ZrSe3 were found to be 1.1 eV and 1.47 eV, respectively. The resistivity of the as grown crystals was measured using van der Pauw
method. The Hall parameters of the grown crystals were determined at room temperature from Hall effect measurements. Electrical
resistivity measurements were performed on this crystal in the temperature range 303–423 K. The crystals were found to exhibit
semiconducting nature in this range. The activation energy and anisotropy measurements were carried out for this crystal.
Pressure dependence of electrical resistance was studied using Bridgman opposed anvils set up up to 8 GPa. The semiconducting
nature of ZrSe3 single crystal was inferred from the graph of resistance vs pressure. The results obtained are discussed in detail. 相似文献
3.
4.
Abhinesh Kumar Prajapati Neha Sharma Rakesh Kumar Jena Preena Shrimal Parth Bagtharia Rajesh Kumar Kaushal 《分离科学与技术》2016,51(13):2276-2283
The electrochemical treatment (ECT) of textile wastewater was carried out in a 1.5 dm3 electrolyte batch reactor using iron electrodes. With the four plate configurations, a current density (CD) of 89.2 A/m2 and a pH value of 8.5 were found to be optimal, at which maximum reduction in chemical oxygen demand (COD) and colour achieved were 86% and 79%, respectively. Loss of 0.0666 kg/m3 iron electrode and 18.44 kWh/m3 power consumption was observed during ECT with a maximum COD reduction of 79%. The settling characteristics of electrochemically treated effluents as well as the characteristics of foam and residue were also analysed. 相似文献
5.
A one-dimensional non-isothermal model for oxygen permeable membrane reactor has been developed to simulate the partial oxidation of methane to produce hydrogen. The performance of two fixed bed reactors (FBRs) viz. one with pure O2 in feed (FBR1), other with air in feed (FBR2), and a membrane reactor (MR) having air in non-reaction side have been studied at various feed conditions and inlet temperatures in order to investigate the effect of these parameters on conversion of methane and yield of hydrogen. The fixed bed reactor with pure O2 in feed has been found to provide better performance as compared to fixed bed reactor with air and membrane reactor. 相似文献
6.
I.M. Somasundram A. Cendrowicz M.L. Johns B. Prajapati D.I. Wilson 《Chemical engineering science》2010,65(22):5990-6000
In wick debinding the binder phase is removed from an injection moulded ceramic part by the capillary action of a wicking powder. The binder is withdrawn in the liquid phase in the form of a front, and fronts originating from parts in close proximity may collide, thereby reducing the potential for the binder to be extracted by the capillarity of the wicking powder. The model presented by Somasundram et al. (2008) is employed here to simulate isothermal debinding of cylindrical parts located in close proximity, using the level-set method to track the progress of binder fronts. Two-dimensional cases were simulated using a commercial finite element solver and the results are compared with preliminary experimental results which show the potential of the model and demand further experimental investigation. A simplified model is also presented which encapsulates the main features of the detailed model for simple geometries. 相似文献
7.
8.
Rupesh S. Chavan P. S. Prajapati Shraddha R. Chavan 《Sensing and Instrumentation for Food Quality and Safety》2011,5(1):33-42
Low-fat sweet syrup cheese ball (Rosogolla) was manufactured by using low-fat cow milk and implementing six different combinations viz. type of chhana and two different
concentrations (40 and 50o Brix) of cooking medium. Experimental Rosogolla samples and control were analysed for physico-chemical,
textural and sensory properties. A 40o Brix concentration of sugar syrup as a cooking medium gave a highly acceptable low-fat
Rosogolla. Average composition of low-fat Rosogolla is, moisture—49.83%, fat—4.66%, protein—11.85%, sorbitol—32.41% and ash—0.90%.
Rheological properties of the most acceptable low-fat Rosogolla were hardness—6.78 N, springiness—5.72 mm, gumminess—3.2 N,
chewiness—18.92 Nmm and stiffness—0.95 N/mm. 相似文献
9.
Fei Tao Pritesh Hiralal Lianbing Ren Yong Wang Qing Dai Gehan AJ Amaratunga Hang Zhou 《Nanoscale research letters》2014,9(1):361
Subwavelength nanostructures are considered as promising building blocks for antireflection and light trapping applications. In this study, we demonstrate excellent broadband antireflection effect from thin films of monolayer silica nanospheres with a diameter of 100 nm prepared by Langmuir-Blodgett method on glass substrates. With a single layer of compact silica nanosphere thin film coated on both sides of a glass, we achieved maximum transmittance of 99% at 560 nm. Furthermore, the optical transmission peak of the nanosphere thin films can be tuned over the UV-visible range by changing processing parameters during Langmuir-Blodgett deposition. The tunable optical transmission peaks of the Langmuir-Blodgett films were correlated with deposition parameters such as surface pressure, surfactant concentration, ageing of suspensions and annealing effect. Such peak-tunable broadband antireflection coating has wide applications in diversified industries such as solar cells, windows, displays and lenses. 相似文献
10.
p-nitrobenzyl triphenyl phosphonium ylide initiated radical polymerisation of MMA in 1-4 dioxane at 65 ± 1°C for 2 h under
a nitrogen blanket, follows ideal kinetics with bimolecular termination. The overall activation energy and average value of
k
p
2/k
t are 75.7 kJ mol and 1.14 × 102 l mol−1 s−1. FTIR Spectroscopy confirms a band of 1,729 cm−1 of the ester group. 1H NMR and 13C NMR confirms methoxy protons at 3.8 δ ppm and 52 δ ppm, respectively. E.S.R studies confirm a free radical mode of polymerisation. TGDTA analysis confirms the atactic nature
of polymer and its thermal stability up to 120°C. Ylide dissociates to give a phenyl radical which is responsible for polymerisation. 相似文献