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101.
C. L. Khetrapal M. M. Dhingra K. Venkata Ramiah P. Usha Bai 《Proceedings Mathematical Sciences》1968,67(6):322-327
Interactions of compounds containing OH group with acrylonitrile, 2 : 3 dichloropropene, allyl cyanide and allyl halides have been studied using NMR and IR techniques. Hydrogen bonds of the type O-H ··· N have been detected. With allyl halides bonds of the type O-H ··· Cl have been detected for allyl chloride only. The value of the equilibrium constant has been calculated for O-H ··· N bonds using IR studies. 相似文献
102.
Analytical expressions are found for the coupled wavenumbers in an infinite fluid-filled cylindrical shell using the asymptotic methods. These expressions are valid for any general circumferential order (n). The shallow shell theory (which is more accurate at higher frequencies) is used to model the cylinder. Initially, the in vacuo shell is dealt with and asymptotic expressions are derived for the shell wavenumbers in the high- and the low-frequency regimes. Next, the fluid-filled shell is considered. Defining a relevant fluid-loading parameter μ, we find solutions for the limiting cases of small and large μ. Wherever relevant, a frequency scaling parameter along with some ingenuity is used to arrive at an elegant asymptotic expression. In all cases, Poisson's ratio ν is used as an expansion variable. The asymptotic results are compared with numerical solutions of the dispersion equation and the dispersion relation obtained by using the more general Donnell-Mushtari shell theory (in vacuo and fluid-filled). A good match is obtained. Hence, the contribution of this work lies in the extension of the existing literature to include arbitrary circumferential orders (n). 相似文献
103.
S. Raghava Iyengar J. Shashidhara Prasad Shanta Venkata Raman 《Molecular Crystals and Liquid Crystals》2013,570(2-4):281-288
Refractive indices of cholesteryl linoleate are determined at different temperatures and order parameters have been calculated in smectic and cholesteric phases. 相似文献
104.
Avula Krishna Kumari Vemulapati Hanuman Reddy Guda Mallikarjuna Reddy Yellala Venkata Rami Reddy Suddala Leelavathi 《Journal of heterocyclic chemistry》2019,56(5):1661-1666
In an effort for development of innovative biologically active agents, a sequence of 1,4‐dihydropyridine analogues was synthesized through the green synthetic method. In addition, all compounds were evaluated for their cytotoxic activities against three human cancer cell lines and mouse melanoma and figured out the most active compounds. Besides, promoter reusability, easy handling of the chemical reagent, simple reaction process, time minimization, ethanol–water solvent compatibility, and cost reduction reagent are key tools for this fruitful path. Thus, these examinations recommended that dihydropyridine and their derivatives are motivating moieties for the discovery of new anticancer drugs. 相似文献
105.
Venkata Naresh Vema Y. Bharathi Kumari Sridhar Musulla Rama Krishnam Raju Addada Srinivasa Rao Alapati 《Tetrahedron letters》2019,60(14):986-988
A concise total synthesis of (3R),(5R)-5-hydroxy-de-O-methyllasiodiplodin and its epimer have been synthesized from commercially available (R)-propylene oxide and Orsellinic acid as starting materials. The key steps involved in the synthesis are Wittig reaction, epoxide ring opening with 1,3-dithiane intermediate and Yamaguchi macrolactonization. 相似文献
106.
D.G.S. Sudhakar Ch. Venkata Ramana Reddy Srinivasa Rao Alapati 《Tetrahedron letters》2019,60(37):151027
An efficient stereoselective total synthesis of balticolid has been accomplished starting from known aldehyde. The key steps involved in this synthesis are Sharpless asymmetric epoxidation, Wittig olefination, alkylation of 1,3-dithiane and Yamaguchi macrolactonization. 相似文献
107.
Amara Venkateswara Rao Basa Ashok Gopireddy Venkata Subbareddy Vatti Chandra Sekhar Gollapudi Venkata Ramanamurthy 《International Journal of Polymer Analysis and Characterization》2019,24(4):346-354
Using aqueous extraction of red sanders powder as a reducing agent, silver and copper bimetallic nanoparticles were in situ generated in cotton fabrics. Silver and copper nanoparticles were also generated separately for comparison. The resulted nanocomposite cotton fabrics (NCFs) were characterized by Fourier transform infrared (FTIR) spectroscopy, scanning electron microscopy (SEM), X-ray diffraction (XRD), thermogravimetric analysis (TGA), and antibacterial tests. SEM analysis indicated the generation of more number of nanoparticles when bimetallic source solutions were used. Further, the size range of the generated bimetallic nanoparticles was found to be lower than when individual metal nanoparticles were generated in NCFs. XRD analysis confirmed the in situ generation of silver and copper nanoparticles when equimolar bimetallic salt source solutions were utilized. The NCFs with bimetallic nanoparticles exhibited higher antibacterial activity against both Gram-negative and Gram-positive bacteria and hence can be considered for applications as antibacterial bed and dressing materials. 相似文献
108.
Mydhili S. P. Sireesha B. Reddy Ch. Venkata Ramana 《Russian Journal of General Chemistry》2019,89(5):1015-1022
Russian Journal of General Chemistry - Evaluation of stability constants of the complexes formed in solution by the biologically important ligands and metal ions can aid in understanding the... 相似文献
109.
Venkata Rao Madduluri Peddinti Nagaiah Challa Prathap Paleti Gidyonu Burri David Raju Kamaraju Seetha Rama Rao 《Journal of Saudi Chemical Society》2019,23(6):678-690
Co3O4/γ-Al2O3 catalysts with variable Co3O4 loadings (5–20 wt%) and deposition of 15% Co3O4 on La2O3/γ-Al2O3 were prepared by wet impregnation method. La2O3-γ-Al2O3 support with variable composition of La2O3 (2–6 wt%) were prepared by co-precipitation method. All the catalysts were tested for oxidative dehydrogenation of ethylbenzene with CO2 as soft oxidant. Among the Co3O4/γ-Al2O3 catalysts, 15% Co3O4/γ-Al2O3 has shown good performance and hence this catalyst has been chosen to investigate the effect of La2O3 species. CO2 pulse chemisorption data indicate more amount of CO2 uptake over 15% Co3O4/4%La2O3/γ-Al2O3 catalyst which clearly indicates that this catalyst exhibits good performance in ethylbenzene dehydrogenation with CO2 as soft oxidant because of reverse water gas shift reaction. Temperature programmed reduction studies indicate that the Co3O4 catalysts follow two step reduction mechanism from Co3O4 to CoO and then to Co and La2O3 promotional effect is visible through facile reduction of Co3O4 species. La2O3 doping has a vital influence in getting enhanced ethylbenzene conversion, styrene yield and alleviates catalyst deactivation compared to that of unpromoted Co3O4/γ-Al2O3 catalyst. TGA studies indicate the presence low amount coke deposition during time-on-stream over 15% Co3O4/4%La2O3/γ-Al2O3 catalyst compared to 15% Co3O4/γ-Al2O3 catalyst. 相似文献
110.
Babu R. Balakrishnan S. Venkata Krishnan R. Senapati Abhiram Ananthasivan K. Joseph Kitheri 《Journal of Thermal Analysis and Calorimetry》2019,136(6):2421-2427
Journal of Thermal Analysis and Calorimetry - Thorium–cerium mixed oxides (Th1?xCex)O2 (x?=?0.25, 0.5, 0.75) were prepared by the citrate gel combustion technique. X-ray... 相似文献