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51.
Thomas Balasingh Sudha Palanisamy Thanikaivelan Meiyazhagan Ashokkumar Bangaru Chandrasekaran 《Applied biochemistry and biotechnology》2011,163(2):247-257
A hybrid protein fiber from different protein sources such as casein and soybean using wet-spinning technique was prepared.
The casein/soybean hybrid fibers were synthesized at different weight ratios such as 100/0 (casein), 75/25, 50/50, 25/75,
and 0/100 (soy) and characterized. Electron microscopic analysis confirmed the growth of pure and hybrid fibers and shows
an increased surface roughness as the soy concentration increases in the hybrid fibers. Infrared spectra did not exhibit any
significant changes in the functional groups between pure and hybrid fibers. X-ray diffraction pattern indicates slight increase
in the diffraction peak values of hybrid fibers compared with the neat fibers. Thermal analyses show a moderate increase in
the thermal stability of hybrid fibers when compared with the pure fibers. These results implicitly indicate that the casein
and soy proteins are homogeneous in the hybrid fiber form. It has been demonstrated that the hybrid fiber with ≥50 wt.% casein
content exhibits better morphology and increased thermal stability, which has scope for application in technical and medical
industries. 相似文献
52.
53.
An efficient method for the dehydration of tertiary alcohols to obtain olefins in high yield, employing methanesulfonyl chloride-triethylamine and catalytic amount of 4-dimethylaminopyridine in dichloromethane, is described. 相似文献
54.
A simple and ecofriendly protocol has been developed for the expedient synthesis of novel dihydroindeno[1,2-b]pyrrol-4(3aH)-ones from the reaction of ninhydrin and (E)-N-methyl-1-(methylthio)-2-nitroethenamine or (E)-N-(1-(methylthio)-2-nitrovinyl)anilines. 相似文献
55.
M. Sudha S. Senthilkumar R. Hariharan A. Suganthi M. Rajarajan 《Journal of Sol-Gel Science and Technology》2012,61(1):14-22
Nanoparticles of uncapped and PVA (poly vinyl alcohol) capped zinc oxide were synthesized by precipitation method. The synthesized
ZnO nanoparticles were characterized by fourier transform infrared spectroscopy, X-ray powder diffraction, scanning electron
microscopy, transmission electron microscopy and thermogravimetric-differential thermal analysis. The photocatalytic activity
of bare and modified ZnO nanoparticles was studied by monitoring the degradation of Rhodamine B. The results show that PVA
capped ZnO nanoparticles has reduced photocatalytic activity than the bare ZnO nanoparticles. The reduction in the chemical
oxygen demand and total organic carbon results also revealed the reduced photocatalytic activity of PVA capped ZnO. The UV-shielding
property was evaluated by measuring the transmittance which shows that both bare and PVA capped ZnO nanoparticles possess
good UV-shielding ability. 相似文献
56.
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58.
Brualdi’s introduction to the concept of poset metric on codes over \(\mathbb {F}_{q}\) paved a way for studying various metrics on \(\mathbb {F}_{q}^{n}\). As the support of vector x in \(\mathbb {F}_{q}^{n}\) is a set and hence induces order ideals and metrics on \(\mathbb {F}_{q}^{n}\), the poset metric codes could not accommodate Lee metric structure due to the fact that the support of a vector with respect to Lee weight is not a set but rather a multiset. This leads the authors to generalize the poset metric structure on to a pomset (partially ordered multiset) metric structure. This paper introduces pomset metric and initializes the study of codes equipped with pomset metric. The concept of order ideals is enhanced and pomset metric is defined. Construction of pomset codes are obtained and their metric properties like minimum distance and covering radius are determined. 相似文献
59.
Recording multiple holographic gratings in silver-doped photopolymer using peristrophic multiplexing
Plane-wave transmission gratings were stored in the same location of silverdoped photopolymer film using peristrophic multiplexing
techniques. Constant and variable exposure scheduling methods were adopted for storing gratings in the film using He-Ne laser
(632.8 nm). The role of recording geometry on the dynamic range of the material was studied by comparing the results obtained
from both techniques. Peristrophic multiplexing with rotation of the film in a plane normal to the bisector of the incident
beams resulted in better homogenization of diffraction efficiencies and larger M/# value. 相似文献
60.
The incorporation of (±)-, norlaudanosoline, ?nor-reticuline, ?N-methylcoclaurine and ?norlaudanidine into thalicarpine in Cocculus laurifolius DC has been studied and specific utilization of (±)- reticuline is demonstrated. The evidence supports that both the “halves” of thalicapine are derived from reticuline. Parallel feedings of (S)-, and (R)-, reticulines showed that the stereospecifity is maintained in the biosynthesis of thalicarpine from the 1-benzyl-tetrahydroisoquinoline precursor.A double-labelling experiment with (±)-[1-3H, 4′-O14CH3] nor-reticuline has shown that the 4′OMe group of a nor-reticuline unit is lost in the biotransformation into thalicarpine. Feeding experiments also revealed that the plants can convert (S)-bolding and (S)-isoboldine into thalicarpine. 相似文献