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81.
Pankaj Bharali Pranjal Saikia Lakshmi Katta Benjaram M. Reddy 《Journal of Industrial and Engineering Chemistry》2013,19(1):327-336
The influence of Hf, Pr and Tb dopant cations on structural and catalytic properties of nanosized CexZr1?xO2 solid solutions has been investigated. A wide range of analytical techniques are utilized to characterize the synthesized materials, and the catalytic activity is evaluated for CO oxidation. XRD, Raman, SEM and TEM results suggested formation of dopant cation incorporated ceria–zirconia solid solutions with highly homogeneous morphology and lattice defects. The CO-TPR measurements revealed an enhanced reducibility of CexZr1?xO2 which is reflected in their better catalytic activity. The role of Tb4+/Tb3+ and Pr4+/Pr3+ redox couples in facilitating a higher activity has been addressed. 相似文献
82.
Putla Sudarsanam Lakshmi Katta Gode Thrimurthulu Benjaram M. Reddy 《Journal of Industrial and Engineering Chemistry》2013,19(5):1517-1524
The present study was undertaken to develop a novel and easy practical approach for synthesis of cyclopentanone, a versatile industrial ingredient. Accordingly, ceria–zirconia based nano-oxide catalysts, namely, CexZr1?xO2 and CexZr1?xO2/M (M = SiO2 and Al2O3) were prepared and evaluated for the title reaction. The physicochemical characterization has been achieved using different techniques, namely, XRD, BET surface area, XPS, Raman, OSC, and HREM. The catalytic results revealed that CexZr1?xO2 based nano-oxides are promising heterogeneous catalysts for synthesis of cyclopentanone. Amongst, the CexZr1?xO2/Al2O3 catalyst exhibited ~100% conversion with 75% desired cyclopentanone product selectivity owing to its favorable physicochemical characteristics. 相似文献
83.
Sakina Khatoon Sunki Reddy Yella Reddy 《European Journal of Lipid Science and Technology》2005,107(11):786-791
Speciality plastic fats with no trans fatty acids suitable for use in bakery and as vanaspati are prepared by interesterification of blends of palm hard fraction (PSt) with mahua and mango fats at various proportions. It was found that the interesterified samples did not show significant differences in solid fat content (SFC) after 0.5 or 1 h reaction time. The blends containing PSt/mahua (1:1) showed three distinct endotherms, indicating a heterogeneity of triacylglycerols (TG), the proportions of which altered after interesterification. The SFC also showed improved plasticity after interesterification. Similar results were observed with other blends of PSt/mahua (1:2). These changes in melting behavior are due to alterations in TG composition, as the trisaturated‐type TG were reduced and the low‐melting TG increased after interesterification. The blends containing PSt/mango (1:1) showed improvement in plasticity after interesterification, whereas those containing PSt/mango (2:1) were hard and showed high solid contents at higher temperature and hence may not be suitable for bakery or as vanaspati. The blends with palm and mahua oils were softer and may be suitable for margarine‐type products. The results showed that the blends of PSt/mahua (1:1, 1:2) and PSt/mango (1:1) after interesterification for 1 h at 80 °C showed an SFC similar to those of commercial hydrogenated bakery shortenings and vanaspati. Hence, they could be used in these applications in place of hydrogenated fats as they are free from trans acids, which are reported to be risk factors involved in coronary heart disease. For softer consistency like margarine applications, the blends containing palm oil and mahua oil are suitable. 相似文献
84.
M.?S.?L.?Karuna J.?R.?C.?Reddy B.?V.?S.?K.?Rao R.?B.?N.?PrasadEmail author 《Journal of surfactants and detergents》2005,8(3):271-276
An efficient and simple lipase-mediated synthesis of alkyl ricinoleates and 12-hydroxy stearates was performed by transesterification
of methyl ricinoleate/12-hydroxy stearate and various alcohols in a solvent-free system without estolide formation. The reaction
conditions were optimized by varying the temperature, pressure, and dosage of lipase. Sulfates of alkyl ricinoleates/12-hydroxy
stearates were evaluated for surfactant properties such as surface tension, critical micelle concentration, emulsifying properties,
foaming power, and calcium tolerance. The surfactant properties of sulfated alkyl ricinoleates were found to be superior to
the sulfated alkyl 12-hydroxy series. The surfactant properties of the above two series of compounds were then compared with
sodium dodecyl sulfate, and the properties of sulfated dodecyl ricinoleate and sulfated dodecyl 12-hydroxy stearate were found
to be comparable with sodium dodecyl sulfate. 相似文献
85.
Ravanamma Rallapalli Muralidhara Reddy Kalimi Ravi Nirlakalla Padma Suvarna Reniguntla 《International Journal of Applied Ceramic Technology》2022,19(4):2053-2063
Structure, morphology, and electrical properties of 10 mol% of Nb2O5-activated yttrium barium titanate (BT) Ba(60-z)Ti(40-x)NbzYxO3 (BTY10Nb10), barium titanate (BT), and 10 mol% of Y2O3-activated BT were explored with calcination and sintering temperatures of 1000°C at 8 h and 1200°C at 6 h, respectively. The thermogravimetric and differential scanning calorimetry (TG–DSC) analysis reported that the total weight loss and residual mass of BT at 1300°C were 16.8 and 83.2%, respectively. The X-ray diffraction (XRD) pattern confirmed that BTY10Nb10 ceramics containing the BaNbO3 phase were developed. A Raman band of BT at 307 cm–1 unveiled a blue shift slightly for BTY10 to 298 cm–1 and for BTY10Nb10 to 306 cm–1. Average pore area of the ferroelectric BTY10Nb10 was found to be 6.96 nm for the total scanning electron microscopy (SEM) image area of 20.31 nm. Formation of BT nanorods analyzed from transmission electron microscopy (TEM) has been reported in three samples that regulate surface roughness. Moreover, Nyquist diagram of BTY10Nb10 shows two overlapping semicircles as a function of frequency. Nanorod structures led to change the morphology and surface roughness. Recoverable energy storage density and energy storage efficiency were estimated as 2.63 µJ/cm3 and 57%, and BTY10Nb10 ferroelectric showed potential for energy storage applications due to changes in surface morphology and porosity. 相似文献
86.
Allister Yingwei Tham Chinnasamy Gandhimathi Jayaraman Praveena Jayarama Reddy Venugopal Seeram Ramakrishna Srinivasan Dinesh Kumar 《International journal of molecular sciences》2016,17(8)
Bone transplants are used to treat fractures and increase new tissue development in bone tissue engineering. Grafting of massive implantations showing slow curing rate and results in cell death for poor vascularization. The potentials of biocomposite scaffolds to mimic extracellular matrix (ECM) and including new biomaterials could produce a better substitute for new bone tissue formation. A purpose of this study is to analyze polycaprolactone/silk fibroin/hyaluronic acid/minocycline hydrochloride (PCL/SF/HA/MH) nanoparticles initiate human mesenchymal stem cells (MSCs) proliferation and differentiation into osteogenesis. Electrospraying technique was used to develop PCL, PCL/SF, PCL/SF/HA and PCL/SF/HA/MH hybrid biocomposite nanoparticles and characterization was analyzed by field emission scanning electron microscope (FESEM), contact angle and Fourier transform infrared spectroscopy (FT-IR). The obtained results proved that the particle diameter and water contact angle obtained around 0.54 ± 0.12 to 3.2 ± 0.18 µm and 43.93 ± 10.8° to 133.1 ± 12.4° respectively. The cell proliferation and cell-nanoparticle interactions analyzed using (3-(4,5-dimethyl thiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium inner salt) MTS assay (Promega, Madison, WI, USA), FESEM for cell morphology and 5-Chloromethylfluorescein diacetate (CMFDA) dye for imaging live cells. Osteogenic differentiation was proved by expression of osteocalcin, alkaline phosphatase activity (ALP) and mineralization was confirmed by using alizarin red (ARS). The quantity of cells was considerably increased in PCL/SF/HA/MH nanoparticles when compare to all other biocomposite nanoparticles and the cell interaction was observed more on PCL/SF/HA/MH nanoparticles. The electrosprayed PCL/SF/HA/MH biocomposite nanoparticle significantly initiated increased cell proliferation, osteogenic differentiation and mineralization, which provide huge potential for bone tissue engineering. 相似文献
87.
Vedhavathi H. S. Divya U. S. Madhukar B. S. Vanga Pradeep Reddy Swamy N. Kumara 《Journal of Inorganic and Organometallic Polymers and Materials》2022,32(5):1853-1867
Journal of Inorganic and Organometallic Polymers and Materials - Herein we have synthesised Gadolinium oxide doped Zinc oxide (Gd2O3@ZnO) by solution combustion method and incorporated it as a... 相似文献
88.
As a result of the varied applications of Hurwitz polynomials in the analysis and design of two-dimensional circuits and systems, several different classes of two-variable Hurwitz polynomials have been defined. The authors provide a comprehensive presentation of the definitions of different classes, the interrelationships among them, and their applications. The place and role of the newly defined principal Hurwitz polynomials among the various Hurwitz polynomials are also brought to light. Using a continuity property of the zeros of two-variable polynomials, new proofs for the test procedures of the different Hurwitz polynomials are presented. Applications of the Hurwitz polynomials in the study of the stability of two-dimensional systems and the properties of two-variable passive networks are summarized 相似文献
89.
Cheng-Wei Lee Hsueh-Pei LuNagannagari Masi Reddy Hsuan-Wei LeeEric Wei-Guang Diau Chen-Yu Yeh 《Dyes and Pigments》2011,91(3):317-323
An acetylene-linked porphyrin-perylene anhydride and an acetylene-linked porphyrin-naphthalic anhydride have been synthesized; the highly conjugated acetylenic bridge in these porpyrins efficiently mediates electronic interaction between the porphyrin and perylene units to extend the π-conjugation of the porphyrin dye and to cause both broadening and red shifts of both the Soret and Q absorption bands. This condition is a useful feature for efficient dye-sensitized solar cell applications. The optical, electrochemical and photovoltaic properties of the new linked anhydrides show that the HOMO-LUMO gap decreased upon extension of π-conjugation, indicating a strong electronic coupling between the porphyrin and the perylene or naphthalene unit. 相似文献
90.
Genetic Diversity and Phylogeny of Antagonistic Bacteria against Phytophthora nicotianae Isolated from Tobacco Rhizosphere 总被引:2,自引:0,他引:2
Jin F Ding Y Ding W Reddy MS Fernando WG Du B 《International journal of molecular sciences》2011,12(5):3055-3071
The genetic diversity of antagonistic bacteria from the tobacco rhizosphere was examined by BOXAIR-PCR, 16S-RFLP, 16S rRNA sequence homology and phylogenetic analysis methods. These studies revealed that 4.01% of the 6652 tested had some inhibitory activity against Phytophthora nicotianae. BOXAIR-PCR analysis revealed 35 distinct amplimers aligning at a 91% similarity level, reflecting a high degree of genotypic diversity among the antagonistic bacteria. A total of 25 16S-RFLP patterns were identified representing over 33 species from 17 different genera. Our results also found a significant amount of bacterial diversity among the antagonistic bacteria compared to other published reports. For the first time; Delftia tsuruhatensis, Stenotrophomonas maltophilia, Advenella incenata, Bacillus altitudinis, Kocuria palustris, Bacillus licheniformis, Agrobacterium tumefaciens and Myroides odoratimimus are reported to display antagonistic activity towards Phytophthora nicotianae. Furthermore, the majority (75%) of the isolates assayed for antagonistic activity were Gram-positives compared to only 25% that were Gram-negative bacteria. 相似文献