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1.
An attempt was made on the modification of the tetraglycidyl‐4,4′‐diaminodiphenyl methane/diaminodiphenyl sulfone (TGDDM/DDS) system to improve properties for several industrial applications. Epoxy resins [TGDDM and 1‐glycidyloxy‐4‐methoxy phenol (GMP)] were synthesized in the laboratory. Also, a new cyanate ester and phenoxy polymer were synthesized and characterized by FTIR, 1H‐/13C‐NMR, and thermal studies. GMP was added as a diluent and a new cyanate ester (DCDPT) was introduced to reduce the tight crosslinking density. Further, a new phenoxy polymer was added to improve the toughness property. A variety of neat resin casts using different compositions of the blends were made and their physical, chemical, thermal, and mechanical properties were evaluated to study the effect of GMP as a diluent, cyanate ester as a comonomer, and phenoxy polymer as a toughener. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 88: 2963–2973, 2003 相似文献
2.
Liquid–liquid–liquid phase transfer catalysis (L–L–L PTC) offers orders of magnitude intensification of rates of reaction and better selectivities than the biphasic PTC. The catalyst-rich middle phase is the main reaction phase. The etherification or alkoxylation of p-chloronitrobenzene (PCNB) was conducted by using alkanol and alkali instead of the metal alkoxide. A kinetic model is presented and validated. 相似文献
3.
Suguna Lakshmi Madurai Stella Winnarasi Joseph Asit Baran Mandal John Tsibouklis Boreddy SR Reddy 《Nanoscale research letters》2011,6(1):15-8
The intercalation of captopril (CP) into the interlayers of montmorillonite (MMT) affords an intestine-selective drug delivery
system that has a captopril-loading capacity of up to ca. 14 %w/w and which exhibits near-zero-order release kinetics. 相似文献
4.
Photocatalytic degradation of pesticide contaminants in water 总被引:2,自引:0,他引:2
Photocatalysis has been proved to be an effective and inexpensive tool for the removal of organic and inorganic pollutants from water. Of particular interest in this context, in recent years, has been the complete photocatalytic mineralisation of a variety of pesticides into harmless products. The technique is now reaching the pre-industrial level, with several pilot plants and prototypes being operational in various countries. This paper reviews the major developments in the area, with special reference to the mechanism of the process involved, nature of the reactive intermediates and final products. 相似文献
5.
Suguna Migeemanathan Rajeev Bhat Wan‐Nadiah Wan‐Abdullah Fook Yee Chye 《International Journal of Dairy Technology》2014,67(3):437-447
Transmission of the thermo‐tolerant pathogen Listeria monocytogenes via contaminated milk and its products, can lead to serious food‐borne illness. In this study, the effects of selected temperatures on survival, percentage injury and inactivation of L. monocytogenes in goat milk samples collected from two different farms were evaluated. Low temperature ranges (0, 5, 10 °C) had a bacteriostatic effect; while at temperatures of 25 and 45 °C, this pathogen grew luxuriantly. However, growth was comparatively slow at 15 °C throughout a 12‐h stress period. Furthermore, a high temperature range (50, 55, 60 and 65 °C) resulted in the elimination of this pathogen within 4 h of stress. Results of Scanning Electron Microscopy showed morphological changes in the cells upon induction of stress temperatures. 相似文献
6.
A new phosphorous containing coupling agent namely, diethylenetriamino-diethylphosphate (DTDP) was synthesized. The structure was confirmed by means of FT-IR, 1H-NMR, 13C-NMR spectra, and mass spectral analysis. The coupling ability of DTDP was investigated by blending it with DGEBA and PDMS, and thus obtained blends have reflected in an increase in the modulus, glass transition temperature and adhesion strength property between the metal-to-metal interface. The high thermal stability, IPDT temperature and flame retardant properties (LOI) were attributed to the presence of phosphorous atom in the coupling agent. 相似文献
7.
R Banerjee K Das R Ravishankar K Suguna A Surolia M Vijayan 《Canadian Metallurgical Quarterly》1996,259(2):281-296
The structure of the complex of the tetrameric peanut lectin with lactose has been refined to an R-value of 16.4% using 2.25 angstroms resolution X-ray diffraction data. The subunit conformation in the structure is similar to that in other legume lectins except in the loops. It has been shown that in the tertiary structure of legume lectins, the short five-stranded sheet plays a major role in connecting the larger flat six-stranded and curved seven-stranded sheets. Furthermore, the loops that connect the strands at the two ends of the seven-stranded sheet curve toward and interact with each other to produce a second hydrophobic core in addition to the one between the two large sheets. The protein-lactose interactions involve the invariant features observed in other legume lectins in addition to those characteristic of peanut lectin. The "open" quaternary association in peanut lectin is stabilised by hydrophobic, hydrogen-bonded and water-mediated interactions. Contrary to the earlier belief, the structure of peanut lectin demonstrates that the variability in quaternary association in legume lectins, despite all of them having nearly the same tertiary structure, is not necessarily caused by covalently bound carbohydrate. An attempt has been made to provide a structural rationale for this variability, on the basis of buried surface areas during dimerisation. A total of 45 water molecules remain invariant when the hydration shells of the four subunits are compared. A majority of them appear to be involved in stabilising loops. 相似文献
8.
Shirshendu Dey Sushama Pethkar Suguna D. Adyanthaya Murali Sastry C. V. Dharmadhikari 《Bulletin of Materials Science》2008,31(3):309-312
A new methodology to anchor λ-DNA to silanized n-Si(111) surface using Langmuir Blodget trough was developed. The n-Si (111) was silanized by treating it with low molecular weight octyltrichlorosilane in toluene. Scanning tunneling microscopy
(STM) image of λ-DNA on octyltrichlorosilane deposited Si substrate shows areas exhibiting arrayed structures of 700 nm length and 40 nm spacing.
Scanning tunneling spectroscopy (STS) at different stages depict a broad distribution of defect states in the bandgap region
of n-Si(111) which presumably facilitates tunneling through otherwise insulating DNA layer. 相似文献
9.
Nasreena Lone In Woo Cheong Min Cho Yong-Ki Hong Yoo Seong Choi Suguna Perumal Byung-Taek Oh Jin Joo 《Journal of Coatings Technology and Research》2017,14(3):621-630
Synthesis of an eco-friendly and efficient antibacterial and antifouling coatings is presented by exploiting urushiol, a natural varnishing material. Since urushiol has inherent outstanding surface-protecting and antimicrobial properties, a series of poly (methyl methacrylate)-urushiol polymer compositions were prepared and fabricated into films. The prepared films were subjected to antimicrobial and antifouling studies. The polymer systems were characterized by various physico-spectroscopic techniques such as 1H NMR, Fourier transform infrared spectroscopy, differential scanning calorimetry, atomic force microscopy, and thermal gravimetric analysis. The confocal laser scanning micrographs, obtained for Pseudomonas aeruginosa biofilm formation, demonstrated an excellent antimicrobial response of the urushiol-incorporated polymers against this bacterial strain. We also demonstrated an inhibitory attachment effect against Navicula incerta, a fouling microalgal strain. 相似文献
10.
Silicon - This paper investigates the RF Stability performance of the Germanium Source Dual Halo Dual Dielectric Triple Material Surrounding Gate Tunnel FET Ge(SRC)-DH-DD-TM-SG-TFET using 3D -... 相似文献