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91.
Nonlinear Dynamics - Based on a non-classical plate theory, a nonlinear analytical model is proposed to analyze transverse vibration of thin partially cracked and submerged orthotropic plate in the... 相似文献
92.
Synthesis of single crystals of calcium iodate by gel method is described. Fairly transparent crystals of reasonably large size with different habits obtained here are illustrated. Crystals grown are identified and characterized by electron microprobe, chemical, X-ray, thermogravimetric and infra-red analysis. 相似文献
93.
Determination of organophosphate pesticides at a carbon nanotube/organophosphorus hydrolase electrochemical biosensor 总被引:7,自引:0,他引:7
Randhir Prakash Deo Joseph Wang Ines Block Ashok Mulchandani Kanchan A. Joshi Marek Trojanowicz Fritz Scholz Wilfred Chen Yuehe Lin 《Analytica chimica acta》2005,530(2):185-189
An amperometric biosensor for oganophosphorus (OP) pesticides based on a carbon nanotube (CNT)-modified transducer and an organophosphorus hydrolase (OPH) biocatalyst is described. A bilayer approach with the OPH layer atop of the CNT film was used for preparing the CNT/OPH biosensor. The CNT layer leads to a greatly improved anodic detection of the enzymatically generated p-nitrophenol product, including higher sensitivity and stability. The sensor performance was optimized with respect to the surface modification and operating conditions. Under the optimal conditions the biosensor was used to measure as low as 0.15 μM paraoxon and 0.8 μM methyl parathion with sensitivities of 25 and 6 nA/μM, respectively. 相似文献
94.
Procedure for hydrothermal synthesis of ZSM-8-type zeolite crystals, using TEA—OH as a template, in the system having molar composition 16.2 (Na2O) — Al2O3 — 117 (SiO2) — 4.8 (TEA)2O — 3887 H2O at 170 °C is described. Results of characterization of these crystals by XRD, IR, EDAX, SEM, TGA, and adsorption studies are described and discussed. X-ray diffraction studies establish that the crystals are ZSM-8-type with structure similar to that of ZSM-5-type crystals. Crystals have prismatic bipyramidal morphology with average size 18–25 microns. Degased calcined samples adsorb xylenes in the order p > m > 0. Pore length per unit cell, estimated from n-hexane adsorption studies, is 46 Å. 相似文献
95.
96.
Polymer composite comprising polyvinylidene fluoride (PVDF) and potassium hexatitante (K2Ti6O13) was synthesized by solution casting. The effect of K2Ti6O13 on surface, thermal, and electrical properties of polymer composite were investigated. The addition of K2Ti6O13 with polymer leads to thermal degradation and transition of polymer composite from semi-crystalline to amorphous phase. The optimum results of contact angle for different loading wt% of K2Ti6O13 were directly correlated with the surface morphology. Our experimental results confirmed the incorporation of K2Ti6O13 in polymer by SEM micrographs. The evaluated dielectric properties (ε' = 424; tan δ = 2.14 at 130 °C and 100 Hz frequency for 20 wt% loading of K2Ti6O13) for polymer composite are higher in compared to pure polymer. The enhancement in dielectric constant and changing the surface properties of polymer composite can be used for the development of electrochemical storage device applications. 相似文献
97.
98.
S.S. Pote C.P. Joshi S.V. Moharil P.L. Muthal S.M. Dhopte 《Physica B: Condensed Matter》2011,406(6-7):1308-1311
Some compounds with fluorite structures in the system CaF2–YF3 were prepared by precipitation followed by thermal annealing at 1000 °C. Photoluminescence spectra of Ce3+ and Eu2+ were studied. In this host, Ce3+ exhibits PL, which is totally different from that observed for the constituent fluorides. Eu2+ emission, on the other hand, is almost the same as that for CaF2. The changes are explained in terms of the defect structure of Ca1?xYxF2+x. 相似文献
99.
100.
In this paper we obtain global controllability of a semilinear system involving monotone nonlinearities of both Lipschitzian and non-Lipschitzian types. 相似文献