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11.
In the present study, an attempt has been made to model and analyze a combined footing supporting column, which is to be constructed on very soft soil. In view of small bearing capacity and very large deflections, foundations are constructed after improving the original ground. Here, the ground has been improved by providing the stone columns in the soft soil and on top of this improved ground; a granular fill layer has been placed just below the footing. The footing has been modeled as a beam having finite flexural rigidity. Granular fill layer, soft soil and stone columns have been represented by Pasternak shear layer, Kelvin–Voigt body and the Winkler springs, respectively. Nonlinear behavior of these has been considered by means of hyperbolic constitutive relationships. Governing differential equations for response of the system have been derived and presented in non-dimensional form. These equations have been solved using appropriate boundary conditions by means of an iterative Gauss Elimination technique.  相似文献   
12.
New filtering scheme is investigated and implemented on digital speckle pattern interferometric fringes to enhance the signal-to-noise ratio (SNR) in the speckle interferograms. To establish the potential of new filtering scheme the experiment was conducted on the vibrating cantilever beam. Experimental results revealed that the new filtering scheme is more powerful than other known filtering schemes (Kumar et al. Opt Laser Eng 2004;41:81–93. Kumar et al. Opt Laser Technol 2001;33:567–571. Shakher et al. Opt Eng 2002;41:176–180. Shakher et al. Proceedings ICICS, Singapore, 9–12 September 1997, p. 953–956. Bowler et al. Proceedings of IEE second international conference on image processing, London, 1986, p. 24–26. Lim. Opt Eng 1981;20:670–678. Devila et al. J Mod Opt 1995;42:1795–1804; Kaufmann et al. Opt Eng 1996;35:9–14). The new scheme reduced the speckle noise and improved SNR in speckle interferograms. Further, the new investigated filtering scheme is implemented to study the mode shapes of square plates under two different boundary conditions. In the first condition all the edges of the square plate were fixed while in the second condition two adjacent edges were fixed and the remaining two edges were free. From the experimental results it is clear that the mode shapes are more distinctly visible with the implementation of the new filtering scheme as compared to other known schemes. Under both the boundary conditions the recorded resonance frequencies were compared with the calculated values of resonance frequencies based on classical theory. The results obtained form DSPI show good agreement with classical theory.  相似文献   
13.
In this paper, we consider the multi-Galerkin and multi-collocation methods for solving the Urysohn integral equation with a smooth kernel, using Legendre polynomial basis functions. Superconvergence results for the approximate and iterated approximate solutions of the proposed methods are obtained in both infinity and \(L^2\)-norm. Numerical examples are presented to illustrate the theoretical results.  相似文献   
14.
Ghosh  Subha  De  Debashis  Deb  Priti  Mukherjee  Anwesha 《Wireless Networks》2020,26(1):349-372
Wireless Networks - The rapid escalation of user traffic and service innovation has made the deployment of small cell base stations essential for eventually decreasing energy consumption in future...  相似文献   
15.
Wireless Personal Communications - Design of energy and spectrum-efficient multi-tier small cell network is an emerging research area. This paper has addressed the challenges of power optimization...  相似文献   
16.
Curcumin is the primary polyphenol in turmeric’s curcuminoid class. It has a wide range of therapeutic applications, such as anti-inflammatory, antioxidant, antidiabetic, hepatoprotective, antibacterial, and anticancer effects against various cancers, but has poor solubility and low bioavailability. Objective: To improve curcumin’s bioavailability, plasma concentration, and cellular permeability processes. The nanocurcumin approach over curcumin has been proven appropriate for encapsulating or loading curcumin (nanocurcumin) to increase its therapeutic potential. Conclusion: Though incorporating curcumin into nanocurcumin form may be a viable method for overcoming its intrinsic limitations, and there are reasonable concerns regarding its toxicological safety once it enters biological pathways. This review article mainly highlights the therapeutic benefits of nanocurcumin over curcumin.  相似文献   
17.
A nonmotile, nonspore-forming, Gram-negative, aerobic, small rod-shaped bacterium, isolated from soil, was identified as Chryseobacterium gleum on the basis of 16S rRNA gene sequence analysis. It was observed to grow luxuriously at pH 9 and tolerate highly alkaline environment up to pH 12. Orange red color was a peculiar character of these cells which on purification obtained 60–80 mg/l and found to be sphingosine type of sulfonolipid “sulfobacin A” on the basis of infrared, nuclear magnetic resonance, and mass spectral data. Inhibition of sulfobacin A synthesis by incorporation of l-cycloserine in culture growth medium suggested presence of serine palmitoyl transferase which is one of the important enzymes involved in its biosynthesis. Sulfobacin A from C. gleum LMG P-22264 exhibited cytotoxicity against four cell lines tested. Maximum activity against human mammary adenocarcinoma cells was indicative of its potential as an anticancer agent.  相似文献   
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19.
A highly enantio- and stereoselective synthetic strategy for both syn- and anti-1,3-polyols has been developed. The sequence involves iterative Jacobsen's hydrolytic kinetic resolution (HKR), diastereoselective iodine-induced electrophilic cyclization, and ring-closing metathesis (RCM). This protocol has subsequently been utilized for the synthesis of cryptocarya diacetate, a natural product with broad range of biological activity.  相似文献   
20.
This paper describes an improved liquid chromatographic (LC) method involving a prechromatographic derivatization step for the estimation of solasodine from berries of various Solanum species, market samples of Solanum xanthocarpum herb, extract, and its market formulations. Solasodine has heterocyclic nitrogen but has no conjugated double bonds in its structure. However, in all reported LC methods, detection was made in the ultraviolet range of 200-213 nm. In the present study, a prechromatographic derivatization of solasodine was done by forming an ion-pair complex of the heterocyclic nitrogen using the acidic dye methyl orange and acetate buffer of pH 4.7. Detection could be made in the visible range at 530 nm in this method. The method was validated and successfully applied to determine solasodine content in various plant samples and polyherbal formulations. The relative standard deviation was found to be 0.025% for system precision, and 0.8% for the linearity of the method, and the correlation coefficient was 0.999. Plant samples and market formulations were analyzed and found to contain solasodine in the range of 0.113-0.227% (w/w) on a fresh weight basis in berries; 0.3-1.278% (w/w) and 0.412% (w/w) on a dry weight basis in S. xanthocarpum herb powder and extract, respectively; and 0.245-0.525% (w/w) on dry weight basis in formulations containing S. xanthocarpum herb powder. No matrix interference was encountered. The method was found to be accurate, with a mean recovery of 100.5 +/- 0.83%. The method has good reproducibility and was found to be suitable for estimation of solasodine.  相似文献   
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