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941.
942.
N. K. Zainuddin M. A. Saadiah A. P. P. Abdul Majeed 《International Journal of Polymer Analysis and Characterization》2018,23(4):321-330
The present work deals with the development of carboxymethyl cellulose (CMC) blended with kappa carrageenan (KC) as a host-based polymer electrolyte (PE) system. The CMC/KC films were successfully prepared using solution casting method and were characterized through electrical impedance spectroscopy, Fourier transform infrared (FTIR) spectroscopy, and X-ray diffraction (XRD) methods, respectively. The FTIR spectrum revealed that the significant region of interaction transpires at wave number 1,057, 1,326, 1,584, and 3,387?cm?1 which correspond to the bending of C–O–C, bending of –OH, asymmetric of –COO? as well as the stretching of –OH, respectively. It has also been demonstrated that the complexation process occurred between CMC and KC. The CMC/KC blend PE system with a ratio of 80:20 achieved an optimum conductivity of 3.91?×?10?7?S?cm?1 and had the lowest crystallinity percentage as suggested by the XRD analysis. 相似文献
943.
Shehar Bano Mahd Rauf Abdul Ghaffar Farhat Yasmeen Waheed-Uz- Zaman 《Natural product research》2020,34(9):1311-1314
AbstractVolatile oil composition of leaves and fruits of Terminalia arjuna (Roxb.) was reported for the first time. Oils were extracted by microwave assisted hydrodistillation where yield of both oils were found to be 0.20% and their GC-MS analyses led to the identification of 65 and 48 constituents, respectively. Major constituents of leaves were carvacrol (11.17%), thymol (6.52%), α-terpinyl acetate (5.92%) and anethole (5.13%) while that of fruits were (E)-isoeugenol (11.48%), furfural (8.25%), p-vinylguaiacol (6.8%) and p-ethylguaiacol (5.72%) that demonstrated a significant difference between composition of its aerial parts, however, 33 constituents were identical that showed similarity characteristics in quality of these oils. Both leaf and fruit oils were found active against pathogenic and drug-resistant microbes: E. coli, Methicillin-resistant S. aureus, P. aeruginosa, Total-drug-resistant P. aeruginosa and K. pneumoniae with MIC values of 0.32, 0.32, 0.64, 0.64, 2.56?mg/mL and 0.16, 0.16, 0.32, 0.64, 1.28?mg/mL, respectively. 相似文献
944.
Xietao Yuan Amir Abdul Razzaq Yujie Chen Yuebin Lian Xiaohui Zhao Yang Peng Zhao Deng 《中国化学快报》2021,32(2):890-894
Lithium polymer batteries(LPBs) rely on a high ion transport to gain improved cell performance.Thermostable and porous gel polymer electrolytes(GPEs) have attracted much attention due to their excellent properties in electrolyte wettability and ionic conductivity.In this work,iron-nickel-cobalt trimetal Prussian blue analogue(PBA) nanocubes are filled into the electro spun polyacrylonitrile(PAN)-based membranes to generate GPE composites with morphological superiority consisting of fine fibers and interconnected pores.The thus obtained PBA@PAN fibrous membrane showcases good thermal stability,high porosity and electrolyte uptake,as well as a peak io nic conductivity of 2.7 mS/cm with the addition of 10% PBA,Consequently,the assembled lithium iron phosphate(LiFePO_4) battery using PBA@PAN-10 as the GPE delivers a high capacity of 152.2 mAh/g at 0.2 C and an ultralow capacity decay of0.09% per cycle in a long-te rm cycle life of 350 cycles at 1 C,endorsing its promising applications in LPBs. 相似文献
945.
Junichi Matsumoto Abdul A. Khan Sam S. Y. Wang Mutsuto Kawahara 《International Journal of Computational Fluid Dynamics》2013,27(2):129-134
This paper presents a computational simulation method for a river problem. For the actual flow problem, it is necessary to compute flow velocity, water elevation and water region at the same time. For the basic formulation, the unsteady shallow water equations are used. As the numerical approach, implicit FEM is proposed by bubble function. To control numerical stability and accuracy, LSBF (Least-Squares Bubble Function) is used to solve the finite element equations. Also, the fixed boundary technique is combined to deal with wet and dry areas in the moving finite element mesh. Some numerical tests are shown to check this method. 相似文献
946.
Choon-Ming Seah Siang-Piao Chai Satoshi Ichikawa Abdul Rahman Mohamed 《Particuology》2013,11(4):394-400
Iron catalyst nanoparticles were prepared on silicon wafers by spin-coating colloidal solutions containing iron nitrate, polyethylene glycol (PEG) and absolute ethanol. The effects of various spin-coating conditions were investigated. The findings showed that the size of the iron particles was governed by the composition of the colloidal solution used and that a high angular speed was responsible for the formation of a thin colloidal film. The effect of angular acceleration on the size and distribution of the iron particles were found to be insignificant. It was observed that a longer spin-coating duration provoked the agglomeration of iron particles, leading to the formation of large particles. We also showed that single-walled carbon nanotubes could be grown from the smallest iron catalyst nanoparticles after the chemical vapor deposition of methane. 相似文献
947.
Abdul Rahman Mohd Kasim Nurul Farahain Mohammad Sharidan Shafie Ioan Pop 《Heat and Mass Transfer》2013,49(2):163-171
The mixed convection boundary layer of a viscoelastic fluid past a circular cylinder with constant heat flux is discussed. The boundary layer equations are an order higher than those for the Newtonian (viscous) fluid and the adherence boundary conditions are insufficient to determine the solution of these equations completely. The governing non-similar partial differential equations are transformed into dimensionless forms and then solved numerically using the Keller-box method by augmenting an extra boundary condition at infinity. Numerical results obtained in the form of velocity distributions and temperature profiles are presented for a range of values of the dimensionless viscoelastic fluid parameter. It is found that for some values of the viscoelastic parameter and some negative values of the mixed convection parameter (opposing flow) the momentum boundary layer separates from the cylinder. Heating the cylinder delays separation and can, if the cylinder is warm enough, suppress the separation completely. Similar to the case of a Newtonian fluid, cooling the cylinder brings the separation point nearer to the lower stagnation point. 相似文献
948.
This paper is devoted to study the modified holographic dark energy model by taking its different aspects in the flat Kaluza-Klein universe. We construct the equation of state parameter which evolutes the universe from quintessence region towards the vacuum. It is found that the modified holographic model exhibits instability against small perturbations in the early epoch of the universe but becomes stable in the later times. We also develop its correspondence with some scalar field dark energy models. It is interesting to mention here that all the results are consistent with the present observations. 相似文献
949.
M. N. Mohd Nasir Z. Yusoff M. H. Al-Mansoori H. A. Abdul Rashid P. K. Choudhury 《Laser Physics》2009,19(10):2027-2030
An efficient multi-wavelength Brillouin-erbium fiber laser utilizing low stimulated Brillouin scattering threshold highly
nonlinear photonic crystal fiber (PCF) is presented. A Fabry-Perot pre-amplified Brillouin pump configuration was used which
consists of 100 m PCF and 10 m erbium doped fiber (EDF). Up to 28 output channels with SNR of more than 20 dB could be generated
with modest pump power. 相似文献
950.