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111.
The law of variation for mean Hubble’s parameter with average scale factor, in an anisotropic Bianchi type V cosmological space–time, is discussed within the frame work of Lyra’s manifold. The variation of Hubble’s parameter, which gives a constant value of deceleration parameter, generates two types of solutions for the average scale factor; one is the power-law and the other one is of exponential form. Using these two forms, new classes of exact solutions of the field equations have been found for a Bianchi type V space–time filled with perfect fluid in Lyra’s geometry by considering a time-dependent displacement field. The physical and kinematical behaviors of the singular and non-singular models of the universe are examined. Exact expressions for look-back time, luminosity distance and event horizon versus redshift are also derived and their significance are discussed in detail. It has been observed that the solutions are compatible with the results of recent observations. 相似文献
112.
The composite of silver-modified lithium manganese oxide were prepared using thermal decomposition method of different mole
ratio. Structural characterization was carried out by X-ray diffraction (XRD). XRD analysis revealed different patterns as
the content of the dopant in the spinel increases. Phase analysis shows that Ag particles were dispersed on the LiMn2O4 surface instead of entering the spinel structure. On the other hand, the electrochemical behavior of cathode powder was examined
by using two-electrode test cells consisting of a cathode, metallic lithium as anode, and a solid polymer electrolyte of 0.87PEO-0.13LiCF3SO3-0.10DBP. According to the electrochemical tests results, the influence of the Ag additive content on the electrochemical
properties of Ag/LiMn2O4 composites is clearly shown. 相似文献
113.
A Lanczos potential for an arbitrary Petrov type D vacuum spacetimes, using the compacted spin coefficient formalism (or GHP-formalism),
has been obtained; which in turn leads to a solution of Weyl-Lanczos equations. 相似文献
114.
Results regarding micromechanical characteristics of gel grown pure- and sodium-modified copper tartrate crystals, bearing composition CuC4H4O6·3H2O, (Cu)0.77(Na)0.23C4H4O6·3H2O and (Cu)0.65(Na)0.35C4H4O6·H2O, as obtained on using indentation induced hardness testing technique are reported. Thermal behaviour of these crystals in the temperature ranging from room temperature (∼25 °C) to about 600 °C is also reported. Pure copper tartrate crystals are found to be thermally more stable than the sodium-modified ones. Dependence of Vickers’ hardness number Hv on load ranging from 0.049 to 2.94 N on two different planes for all the three compositions is analyzed. It is shown that after initial rise in the value of Hv, the same achieves saturation at a load of 0.49 N. Modification of copper tartrate crystal by introducing sodium in its lattice brings about a change in the micromechanical characteristics. The saturation value of Hv decreases with increase in the concentration of sodium ions. The results on (0 0 1) and (1 1 1) planes for both pure and modified copper tartrate crystals suggest hardness anisotropy. Relative difference of hardness between the two planes and yield strength for both pure and modified copper tartrate crystals is worked out. The experimental results are analyzed for applicability of Meyer’s law and Proportional Specimen Resistance Model. It is suggested that the experimental results indicating reverse ISE phenomenon may be explained in terms of the existence of a distorted zone near the crystal-medium interface. The integral method of Coats and Redfern approximation applied to the thermoanalytical data suggests “Random Nucleation Model” for the reaction kinetics of these crystals. Non-isothermal kinetic parameters such as activation energy, frequency factor and order of reaction are calculated. 相似文献
115.
The objective of this note is to provide some(potentially useful) integral transforms(for example, Euler, Laplace, Whittaker etc.) associated with the generalized k-Bessel function defined by Saiful and Nisar [3]. We have also discussed some other transforms as special cases of our main results. 相似文献
116.
Mohd Yusuf Khan Xiangxiong Chen Seung Woo Lee Seok Kyun Noh 《Macromolecular rapid communications》2013,34(15):1225-1230
Atom transfer radical polymerization (ATRP) catalyzed by high oxidation state metal salts of FeX3 is developed for the first time in the absence of both external initiator and reducing agent. Methyl methacrylate (MMA) and styrene are polymerized successfully using FeX3/Phosphorous ligands with well‐controlled molecular weight distributions (=1.5). The molecular weight of the polymers increases with monomer consumption with the progress of time and the polymerization behaviors show a decent ATRP trend. Activators and initiators are suggested to generate in situ by the addition reaction of MMA and one equivalent of FeX3. The PMMA synthesized from without‐initiator system is characterized by 1H, 13C and DEPT (distortionless enhancement by polarization transfer nuclear magnetic resonance) nuclear magnetic resonance spectroscopy. Chain extension and copolymerization experiments prove the livingness of the obtained polymer.
117.
Hasliza Hassan Mohd Din Amiruddin Wolfram Weckwerth Umi Salamah Ramli 《Electrophoresis》2019,40(2):254-265
Palm oil is an edible vegetable oil derived from lipid‐rich fleshy mesocarp tissue of oil palm (Elaeis guineensis Jacq.) fruit and is of global economic and nutritional relevance. While the understanding of oil biosynthesis in plants is improving, the fundamentals of oil biosynthesis in oil palm still require further investigations. To gain insight into the systemic mechanisms that govern oil synthesis during oil palm fruit ripening, the proteomics approach combining gel‐based electrophoresis and mass spectrometry was used to profile protein changes and classify the patterns of protein accumulation during these complex physiological processes. Protein profiles from different stages of fruit ripening at 10, 12, 14, 15, 16, 18 and 20 weeks after anthesis (WAA) were analysed by two‐dimensional gel electrophoresis (2DE). The proteome data were then visualised using a multivariate statistical analysis of principal component analysis (PCA) to get an overview of the proteome changes during the development of oil palm mesocarp. A total of 68 differentially expressed protein spots were successfully identified by matrix‐assisted laser desorption/ionisation‐time of flight (MALDI‐TOF/TOF) and functionally classified using ontology analysis. Proteins related to lipid production, energy, secondary metabolites and amino acid metabolism are the most significantly changed proteins during fruit development representing potential candidates for oil yield improvement endeavors. Data are available via ProteomeXchange with identifier PXD009579. This study provides important proteome information for protein regulation during oil palm fruit ripening and oil synthesis. 相似文献
118.
Isahak Wan Nor Roslam Wan Hasan Siti Zubaidah Ramli Zatil Amali Che Ba-Abbad Muneer M. Yarmo Mohd Ambar 《Research on Chemical Intermediates》2019,45(3):951-953
Research on Chemical Intermediates - 相似文献
119.
Asghar Anam Raman Abdul Aziz Abdul Daud Wan Mohd Ashri Wan Ramalingam Anantharaj Zain Sharifuddin Bin Md 《Research on Chemical Intermediates》2019,45(6):3311-3327
Research on Chemical Intermediates - Hydrogen peroxide (H2O2) is commercially produced by catalytic oxidation of anthrahydroquinone, which is energy-intensive. Electrochemical production of... 相似文献
120.
CH.B. Praveena Devi K. Vijay B. Hari Babu Syed Farooq Adil M. Mujahid Alam M. Vijjulatha Mohd. Bismillah Ansari 《Journal of Saudi Chemical Society》2019,23(7):980-991
A novel series of conjugates of benzosuberone and 1,2,3-triazole i.e. 3-(4-phenyl-1H-1,2,3-triazol-1-yl)propyl-9-chloro-2,3-dimethyl-6,7-dihydro-5H-benzo[7]annulene-8-carboxylic acids (8a-j) were synthesized in good to excellent yields catalysed by CuSO4 under milder reaction conditions and evaluated for their anti-proliferative activity. The structural elucidation of the prepared compounds was carried out using IR, 1H NMR, 13C NMR and Mass spectral analysis. The newly synthesized derivatives (8a-j) were evaluated for their anti-proliferative activity against four human cell lines and the novel derivatives showed moderate to excellent activity. The obtained results suggest that these compounds can be considered as new hits for anti-proliferative drug development programme and further SAR studies can help obtain better anticancer agents. 相似文献