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1.
P.S. Vijayanand 《European Polymer Journal》2007,43(5):2046-2056
The novel methacrylic monomer, 4-nitro-3-methylphenyl methacrylate (NMPM) was synthesized by reacting 4-nitro-3-methylphenol dissolved in ethyl methyl ketone (EMK) with methacryloyl chloride in the presence of triethylamine as a catalyst. The homopolymer and copolymers of NMPM with glycidyl methacrylate having different compositions were synthesized by free radical polymerization in EMK solution at 70 ± 1 °C using benzoyl peroxide as free radical initiator. The homopolymer and the copolymers were characterized by FT-IR, 1H NMR and 13C NMR spectroscopic techniques. The solubility tests were tested in various polar and non-polar solvents. The molecular weight and polydispersity indices of the copolymers were determined using gel permeation chromatography. The glass transition temperature of the copolymers increases with increase in NMPM content. The thermogravimetric analysis of the polymers performed in air showed that the thermal stability of the copolymer increases with NMPM content. The copolymer composition was determined using 1H NMR spectra. The monomer reactivity ratios were determined by the application of conventional linearization methods such Fineman-Ross (r1 = 1.862, r2 = 0.881), Kelen-Tudos (r1 = 1.712, r2 = 0.893) and extended Kelen-Tudos methods (r1 = 1.889, r2 = 0.884). 相似文献
2.
Vijayanand Chandrasekaran Eugen Johannes Hauke Kobarg Frank D S?nnichsen Thisbe K Lindhorst 《ChemistryOpen》2014,3(3):99-108
Spatial orientation of carbohydrates is a meaningful parameter in carbohydrate recognition processes. To vary orientation of sugars with temporal and spatial resolution, photosensitive glycoconjugates with favorable photochromic properties appear to be opportune. Here, a series of azobenzene glycosides were synthesized, employing glycoside synthesis and Mills reaction, to allow “switching” of carbohydrate orientation by reversible E/Z isomerization of the azobenzene N=N double bond. Their photochromic properties were tested and effects of azobenzene substitution as well as the effect of anomeric configuration and the orientation of the sugars 2-hydroxy group were evaluated. 相似文献
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Synthesis and Surface‐Spectroscopic Characterization of Photoisomerizable glyco‐SAMs on Au(111) 下载免费PDF全文
Dr. Vijayanand Chandrasekaran Hanne Jacob Finn Petersen Dr. Ketheeswari Kathirvel Prof. Dr. Felix Tuczek Prof. Dr. Thisbe K. Lindhorst 《Chemistry (Weinheim an der Bergstrasse, Germany)》2014,20(28):8744-8752
Photoisomerizable glyco‐SAMs (self‐assembled monolayers), utilizing synthetic azobenzene glycoside derivatives were fabricated. The ultimate goal of this project is to assay the influence of the 3D arrangement of sugar ligands on cell adhesion, and eventually make cell adhesion photoswitchable. However, it is a prerequisite for any biological study on the spatial conditions of carbohydrate recognition, that photoisomerization of the surface molecules can be verified. Here, we employed IRRAS and XPS to spectroscopically characterize glyco‐SAMs. In particular and unprecedented to date, we prove reversible E→Z→E isomerization of azobenzene glycoside‐terminated SAMs. 相似文献
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Surendra V. Singh Jayaram Vishakantaiah Jaya K. Meka Vijayan Sivaprahasam Vijayanand Chandrasekaran Rebecca Thombre Vijay Thiruvenkatam Ambresh Mallya Balabhadrapatruni N. Rajasekhar Mariyappan Muruganantham Akshay Datey Hugh Hill Anil Bhardwaj Gopalan Jagadeesh Kalidevapura P. J. Reddy Nigel J. Mason Bhalamurugan Sivaraman 《Molecules (Basel, Switzerland)》2020,25(23)
The building blocks of life, amino acids, are believed to have been synthesized in the extreme conditions that prevail in space, starting from simple molecules containing hydrogen, carbon, oxygen and nitrogen. However, the fate and role of amino acids when they are subjected to similar processes largely remain unexplored. Here we report, for the first time, that shock processed amino acids tend to form complex agglomerate structures. Such structures are formed on timescales of about 2 ms due to impact induced shock heating and subsequent cooling. This discovery suggests that the building blocks of life could have self-assembled not just on Earth but on other planetary bodies as a result of impact events. Our study also provides further experimental evidence for the ‘threads’ observed in meteorites being due to assemblages of (bio)molecules arising from impact-induced shocks. 相似文献
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Nitin Wadnerkar Vijayanand Kalamse Ajay Chaudhari 《Theoretical chemistry accounts》2010,127(4):285-292
Using density functionals theory, we show that gravimetric hydrogen uptake of C2H4Ti complex and its cation, C2H4Ti+, differ by about 2 wt%. Six and five hydrogen molecules are found to be adsorbed on C2H4Ti+ and C2H4Ti complexes thereby showing a hydrogen-uptake capacity of 13.74 and 11.72 wt%, respectively. All hydrogen molecules are adsorbed
in molecular form on C2H4Ti+ ion with an increase in metal bond strength, whereas in some cases, the hydrogen molecules are found to be dissociated on
C2H4Ti neutral complex. The uptake capacity of neutral C2H4Ti complex shown in this work is in excellent agreement with that reported experimentally, Phillips and Shivaram (Phys Rev
Lett 100:105505, 2008). The H2 adsorption energy and its dependence on exchange and correlation functions in density functionals method were illustrated.
Even after the adsorption of maximum number of hydrogen molecules on C2H4Ti and C2H4Ti+ complexes, Ti and Ti+ remain strongly bound to C2H4 substrate. 相似文献
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Janakiraman Vivekanandan Arunachalam Mahudeswaran Xiao-Yan Tang Sangamesh G. Kumbar Pachanoor Subbaian Vijayanand 《Chemical Papers》2015,69(7):964-972
Novel copolymers of poly(aniline-co-m-chloroaniline)-doped dodecylbenzenesulphonic acid (DBSA) with embedded silver nanoparticles were synthesised using the in situ chemical oxidative method. The structural properties of the copolymers were characterised using the UV-VIS and FTIR spectroscopic methods. The crystalline nature of the copolymer was demonstrated by way of the X-ray diffraction (XRD) pattern. Scanning electron microscopy (SEM) revealed the presence of particle agglomerates measuring 50 nm to 100 nm on the surface of the nanocomposites. The electrical conductivity of the copolymer was dependent on the monomer composition and was found to be in the range of 10?2 S cm?1 to 10?6 S cm?1 with an increasing chloroaniline content and exhibiting improved solubility. 相似文献
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The properties of nanocrystalline Ni0.5Zn0.5Fe2O4 synthesized by an auto-combustion method have been investigated by magnetic measurements and Mössbauer spectroscopy. The as-synthesized single phase nanosized ferrite powder is annealed at different temperatures in the range 673–1,273 K to obtain nanoparticles of different sizes. The powders are characterized by powder X-ray diffraction, vibrating sample magnetometer, transmission electron microscopy and Mössbauer spectroscopy. The as-synthesized powder with average particle size of ~9 nm is superparamagnetic. Magnetic transition temperature increases up to 665 K for the nanosized powder as compared to the transition temperature of 548 K for the bulk ferrite. This has been confirmed as due to the abnormal cation distribution, as evidenced from room temperature Mössbauer spectroscopic studies. 相似文献
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Challa Prathap Paleti Gidyonu Madduluri Venkata Rao Gadamani Suresh Babu Pothu Ramyakrishna Burri David Raju Boddula Rajender Perugopu Vijayanand Kamaraju Seetha Rama Rao 《Catalysis Surveys from Asia》2022,26(2):80-91
Catalysis Surveys from Asia - At this moment the major challenge for the human beings is to address uninterrupted raise in CO2 emissions and their consequences. The demands of globalization... 相似文献
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Arunkumar Lagashetty H. Vijayanand S. Basavaraja Mahesh D. Bedre A. Venkataraman 《Journal of Thermal Analysis and Calorimetry》2010,99(2):577-581
Polycarbonate with γ-Fe2O3 and CuO dispersions were carried out by solvent casting method to make polycarbonate-γ-Fe2O3 and polycarbonate-CuO composite films. These films were characterized for the molecular structure through FTIR spectroscopy
and crystallinity by X-ray diffraction (XRD) measurements. The morphology of polycarbonate-γ-Fe2O3 was found to be different from that of polycarbonate-CuO composite films based on the scanning electron micrograph (SEM)
images. The thermal traces of composites are different from that of pure polycarbonate which indicating the catalytic decomposition
when compared with virgin polymer which is oxidative decomposition. An understanding of the structure, morphology, and thermal
behaviour of the composite films are envisaged in the present study. 相似文献