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21.
In this work a formula for the second regularized trace of a self adjoint differential operator which is given in a finite interval and with bounded operator coefficient was found.  相似文献   
22.
In this paper, we study the approximation properties of nonlinear integral operators of convolution-type by using summability process. In the approximation, we investigate the convergence with respect to both the variation semi-norm and the classical supremum norm. We also compute the rate of approximation on some appropriate function classes. At the end of the paper, we construct a specific sequence of nonlinear operators, which verifies the summability process. Some graphical illustrations and numerical computations are also provided.  相似文献   
23.
In this paper, we investigate the problem of statistical approximation to a function by means of positive linear operators defined on a modular space. Especially, in order to get more powerful results than the classical aspects we mainly use the concept of statistical convergence. A non-trivial application is also presented.  相似文献   
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In this work, we study the statistical approximation properties of the double-complex Picard integral operators. We also show that our statistical approach is more applicable than the classical one.  相似文献   
26.
In this study, dithizone (diphenylthiocarbazone) has been separately radiolabeled with 131I and with 99mTc for preliminarily testing their radiopharmaceutical potentials on male albino rabbits. 131I-dithizone and 99mTc-dithizone were intravenously injected to rabbits via their ear veins after anesthetizing with a mixture of Alfazyne and Alfamine (Serva) to determine their dynamic and static statuses in the metabolism. Also, 99mTc as pertechnetate and 131I as iodate were administered to rabbits as controls. Dynamic and static scintigrams were obtained using a gamma camera (Diacan Instruments). Dynamic scintigrams were obtained over the first half hour with frames of 1 minute following the administrations of the labeled compounds. Static images were obtained from posterior projection at different time intervals up to about 3 hours following the administration of the radiolabeled compounds. 99mTc-dithizone was significantly uptaken by the pancreas in contrast to free 99mTc. In the case of 131I-dithizone, the distribution of 131I activity in the metabolism was clearly different than the case of free 131I and the uptake of 131I-dithizone at the pancreas zone was also significant. These preliminary tests have clearly indicated that especially 99mTc-dithizone has a significant potential to be used as a pancreatic radiopharmaceutical.  相似文献   
27.
A new approach for solving the laminar flow problem above a porous medium is presented here, using an apparent interface for which both superficial velocity and intrinsic shear stress are continuous. The derivation of this approach is based on a detailed investigation of the Ochoa-Tapia and Whitaker (Int. J. Heat Mass Transfer 38:2635–2646, 1995a) jump condition and its sensitivity to the value of β (the jump condition coefficient) and to an error in the interface location. While the value of the jump condition coefficient is highly sensitive to the interface location, the new apparent interface approach does not require an a priori information about the location of the interface. This approach can be easily used knowing only one measurable parameter—the maximum velocity or the flow rate. Validation of the apparent interface approach against measurements from other works shows that it can be successfully used to predict the velocity profile for different geometrical models.  相似文献   
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In this study, our investigations showed that the increasing concentrations of all examined mono alcohols caused a decrease in the V m, k cat and k cat/K m values of Bacillus clausii GMBE 42 serine alkaline protease for casein hydrolysis. However, the K m value of the enzyme remained almost the same, which was an indicator of non-competitive inhibition. Whereas inhibition by methanol was partial non-competitive, inhibition by the rest of the alcohols tested was simple non-competitive. The inhibition constants (K I) were in the range of 1.32–3.10 M, and the order of the inhibitory effect was 1-propanol>2-propanol>methanol>ethanol. The ΔG and ΔG E???T values of the enzyme increased at increasing concentrations of all alcohols examined, but the ΔG ES value of the enzyme remained almost the same. The constant K m and ΔG ES values in the presence and absence of mono alcohols indicated the existence of different binding sites for mono alcohols and casein on enzyme the molecule. The k cat of the enzyme decreased linearly by increasing log P and decreasing dielectric constant (D) values, but the ΔG and ΔG E???T values of the enzyme increased by increasing log P and decreasing D values of the reaction medium containing mono alcohols.  相似文献   
30.
The thermal and magnetothermal properties of La0.5Pr0.5Mn2Si2 and isostructural LaFe2Si2 intermetallic compounds in the temperature range 4.5-303 K are reported with and without applied magnetic field. The electronic, lattice, and magnetic contributions to the heat capacity of La0.5Pr0.5Mn2Si2 are determined and analyzed. We have determined and from heat capacity experiments; the values are in line with those from the magnetization measurements. We conclude that in order to observe the anomaly in the heat capacity data around in the system, the transition around should occur in a narrow temperature interval.  相似文献   
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