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51.
We present here a ‘similar’ solution for the nano boundary layer with nonlinear Navier boundary condition. Three types of flows are considered: (i) the flow past a wedge; (ii) the flow in a convergent channel; (iii) the flow driven by an exponentially-varying outer flows. The resulting differential equations are solved by the homotopy analysis method. Different from the perturbation methods, the present method is independent of small physical parameters so that it is applicable for not only weak but also strong nonlinear flow phenomena. Numerical results are compared with the available exact results to demonstrate the validity of the present solution. The effects of the slip length ?, the index parameters n and m on the velocity profile and the tangential stress are investigated and discussed. 相似文献
52.
Sensitivity analysis for cocoercively monotone variational inclusions and (A,η)-maximal monotonicity
Sensitivity analysis for cocoercively monotone variational inclusions based on the generalized resolvent operator technique is discussed. The notion of the cocoercive monotonicity unifies most of the existing notions, such as cocoercivity, strong monotonicity, relaxed monotonicity, relaxed cocoercivity, and others. As a result, the obtained results are general in nature. 相似文献
53.
Bhim Bali Prasad Khushaboo Tiwari Meenakshi Singh Piyush S. Sharma Amit K. Patel Shrinkhala Srivastava 《Chromatographia》2009,69(9-10):949-957
A combination approach in solid-phase microextraction, based on a molecularly imprinted polymer-brush coating on an optical fiber coupled with a complementary molecularly imprinted polymer sensor, has been adopted for isolation, preconcentration, and analysis of dopamine at ultratrace levels in highly dilute aqueous samples. This combination enabled enhanced (up to 8.5-fold) preconcentration of the analyte, which is appropriate for achieving a stringent detection limit in clinical diagnosis of several neurodegenerative diseases. The detection limit of dopamine in biological samples was 0.018 ng mL?1 with a relative standard deviation less than 2.1% and without any non-specific contributions. 相似文献
54.
55.
Vinod Chhokar Meenakshi Sangwan Vikas Beniwal Kiran Nehra Kaur S. Nehra 《Applied biochemistry and biotechnology》2010,160(8):2256-2264
Tannase from Aspergillus awamori MTCC 9299 was purified using ammonium sulfate precipitation followed by ion-exchange chromatography. A purification fold
of 19.5 with 13.5% yield was obtained. Temperature of 30 °C and pH of 5.5 were found optimum for tannase activity. The effects
of metals and organic solvents on the activity of tannase were also studied. Metal ions Mg+2, Mn+2, Ca+2, Na+, and K
+
stimulated the tannase activity, while Cu+2, Fe+3, and Co+2 acted as inhibitors of the enzyme. The addition of organic solvents like acetic acid, isoamylalcohol, chloroform, isopropyl
alcohol, and ethanol completely inhibited the enzyme activity. However, butanol and benzene increased the enzyme activity. 相似文献
56.
S. Chowta P. K. Mohapatra S. C. Tripathi B. S. Tomar V. K. Manchanda 《Journal of Radioanalytical and Nuclear Chemistry》2010,285(2):309-314
Radiochemical results of U isotopes (234U, 235U and 238U) and their activity ratios are reported for well waters as local sources of drinking waters collected from the ten settlements
around the Semipalatinsk Nuclear Test Site (SNTS), Kazakhstan. The results show that 238U varies widely from 3.6 to 356 mBq/L (0.3–28.7 μg/L), with a factor of about 100. The 238U concentrations in some water samples from Dolon, Tailan, Sarzhal and Karaul settlements are comparable to or higher than
the World Health Organization’s restrictive proposed guideline of 15 μg (U)/L. The 234U/238U activity ratios in the measured water samples are higher than 1, and vary between 1.1 and 7.9, being mostly from 1.5 to
3. The measured 235U/238U activity ratios are around 0.046, indicating that U in these well waters is of natural origin. It is probable that the elevated
concentration of 238U found in some settlements around the SNTS is not due to the close-in fallout from nuclear explosions at the SNTS, but rather
to the intensive weathering of rocks including U there. The calculated effective doses to adults resulting from consumption
of the investigated waters are in the range 1.0–18.7 μSv/y. Those doses are lower than WHO and IAEA reference value (100 μSv/y)
for drinking water. 相似文献
57.
58.
M. Mohapatra Y.P. NaikV. Natarajan T.K. SeshagiriS.V. Godbole 《Physica B: Condensed Matter》2011,406(10):1977-1982
Lithium titanate ceramics doped with Eu were synthesized and their photoluminescence (PL) and emission spectral characteristics were investigated. PL spectra of the sample showed peaks corresponding to the 5D0→7FJ (J=0, 1, 2, 3 and 4) transitions under 230 nm excitation. The fluorescence lifetimes of Eu3+ ions were found out to be 645 μs. Strong red emission coming from the hypersensitive 5D0→7F2 transition of Eu3+ ion suggested the presence of the dopant ion in highly asymmetric environment. Further analysis of the emission spectrum revealed that the symmetry of the metal ion is very low i.e. C2. The emission intensity of the sample was compared with a commercial phosphor to get an idea about the commercial utility of the phosphor. Various emission properties for the system namely Judd-Ofelt intensity parameters, spontaneous emission probabilities, branching ratios, radiative lifetimes and quantum efficiency were evaluated for the dopant ion by adopting standard procedure. 相似文献
59.
Anita Pati Snigdha Mohapatra Rajani K. Behera 《Journal of heterocyclic chemistry》2011,48(6):1234-1237
The syntheses of an important class of hitherto unreported spiro derivatives containing benzo[f]chromanone moiety involving very simple cyclocondensation reactions are described. Installation of pharmacologically active moieties like thiazolidine and thiazolidinone is achieved by taking simple reagents like ethylchloroacetate, 1, 2‐dibromo ethane and thioglycollic acid. J. Heterocyclic Chem., (2011). 相似文献
60.
P. K. Mohapatra V. K. Manchanda 《Journal of Radioanalytical and Nuclear Chemistry》1999,241(1):101-105
The extraction behavior of Am3+ and UO2
2+ is investigated employing chloroform solution of 18-crown-6 as the organic phase and picrate solution at pH 3.0 as the aqueous
phase. In contrast to the commonly observed behavior, the extraction of Am3+ is preferred to that of UO2
2+. This unusual separation behavior is investigated as a function of several variable parameters such as crown ether concentration,
picric acid concentration, inert electrolyte concentration, nature of diluent etc. Thermodynamic parameters are also evaluated. 相似文献