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91.
Neil B. Cramer Sirish K. Reddy Hui Lu Tsali Cross Rishi Raj Christopher N. Bowman 《Journal of polymer science. Part A, Polymer chemistry》2004,42(7):1752-1757
The liquid, ceramic precursor monomer VL20 was copolymerized with a thiol monomer in a traditional radical thiol‐ene photopolymerization. Polymerization occurred via addition of the thiol functional group to the vinyl silazane functional group in a 1:1 ratio consistent with a step‐growth polymerization. Gelation occurred at a high conversion of functional groups (70%) consistent with an average molecular weight and functionality of 560 and 1.7, respectively, for VL20 monomers. Initiatorless photopolymerization of the thiol‐VL20 system also occurred upon irradiation at either 365 or 254 nm. © 2004 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 42: 1752–1757, 2004 相似文献
92.
Savithri Srinivasan Rishi Ram 《Zeitschrift für Angewandte Mathematik und Physik (ZAMP)》1975,26(3):307-313
The propagation of a sonic discontinuity in an optically thick gray gas at temperature 105°K or higher has been studied. The effects of radiation pressure and radiation energy density have been taken into account, while the profiles structured by radiant heat transfer are imbedded in the discontinuities under high temperature conditions of an optically thick medium. When the sonic discontinuity is propagating into a gas at rest, its velocity of propagation is found to be a constant which is the effective speed of sound in a radiating gas. The fundamental differential equations governing the growth of the sonic discontinuity are obtained and solved. It is concluded that if the sonic discontinuity is a compressive wave of order 1, then it terminates into a shock wave after a critical timet c which has been determined. But on the other hand, when the sonic discontinuity is an expansion wave of order 1, then it will decay and will vanish ultimately. Particular cases of interest have been studied in details. 相似文献
93.
Conclusion The method proposed above is convenient for rapid analysis of many samples where extremely high accuracy is not required especially with sulphate determination. 相似文献
94.
Muszkat L Feigelson L Bir L Muszkat KA 《Journal of photochemistry and photobiology. B, Biology》2001,60(1):32-36
The TiO2 photocatalyzed oxidation of the proteins serum albumin, ovalbumin and gamma globulin, is reported. All the amino acids were susceptible to photocatalytic oxidation. However, some were especially vulnerable. Tyrosine was particularly sensitive, as was the semiaromatic histidine, although to a lesser extent. The lack of an activating group on the aromatic ring in Phe, renders the system less amenable to degradation. The photocatalytic degradation of the aliphatic amino acids Gly and Asp, was particularly slow, like in the Fenton oxidation where production of glycine was observed during the cleavage of collagen induced by hydroxyl radicals. Intermediate degradation rate was noticed in Ser, Arg, Val, Cys and Phe. 相似文献
95.
We argue that the quantized non-Abelian gauge theory can be obtained as the infrared limit of the corresponding classical gauge theory in a higher dimension. We show how the transformation from classical to quantum field theory emerges, and calculate Planck's constant from quantities defined in the underlying classical gauge theory. 相似文献
96.
A. Kremenović D. Poleti N. E. Ghermani L. Karanović U. B. Mioč Z. Nedić A. Spasojević-de Biré 《Crystal Research and Technology》2007,42(1):98-104
Crystals suitable for X-ray structure analysis were obtained after the slow evaporation of the reaction mixture containing equimolar quantities of magnesium chloride and dodecatungstophosphoric acid aqueous solution insuring pH of the solution between 1.0 and 1.2. This simple synthetic route yielded stability of Keggin anion and high quality [Mg(H2O)6][HPW12O40]·4H2O single crystals. The obtained compound belongs to the group of heteropoly compounds and its structure is composed of Keggin [PW12O40]3– anions, [Mg(H2O)6]2+ cations and lattice water molecules. Zigzag arrangement of Keggin anions along c-axis creates irregular channels occupied by [Mg(H2O)6]2+ cations and lattice H2O molecules. The calculation of the total potential solvent volume indicated the presence of 4.1 lattice H2O lattice molecules per formula unit, which is in agreement with the here presented structural model. The position of one lattice water molecule is well defined, while each of three other molecules is statistically distributed over two locations. Hydrogen bonds involve all coordinated and lattice H2O molecules, as well as some oxygen atoms from the Keggin anion. (© 2007 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
97.
98.
Pathania Preeti Sharma Arunima Kumar Binod Rishi Praveen Raman Suri C. 《Mikrochimica acta》2017,184(5):1499-1508
Microchimica Acta - The authors report on an aptamer-based method for the detection of S. Typhimurium. The aptamers were identified by using a modified cell-based SELEX method (cell-SELEX) by... 相似文献
99.
Alexander A. Kamnev Anna V. Tugarova Borbála Biró Krisztina Kovács Zoltán Homonnay Ern? Kuzmann Attila Vértes 《Hyperfine Interactions》2012,208(1-3):91-94
The Thylacine Hole–001 meteorite was recovered from the Nullarbor Desert (Australia) in 1977 and is an Ordinary Chondrite, Group H4/5br, which has undergone moderate to severe (B/C) weathering. We have characterised the Fe-bearing phases in Thylacine Hole–001 by 57Fe M?ssbauer Spectroscopy at 300?K, 100?K, 50?K and 4?K. The spectrum at 300?K is dominated by the paramagnetic doublets of Olivine, Pyroxene and a Ferric component which is most likely nanoparticulate Goethite. Magnetically split sextets due to Maghemite or Magnetite are also present, consistent with the relatively advanced terrrestrial age of 28,500 yrs The nanoparticulate Goethite component shows a blocked, magnetically split sextet at low temperatures. We also observe the effects of magnetic ordering of the Olivine and Pyroxene below 50?K. 相似文献
100.
P. L. Neumann V. I. Obreczán G. Dobrik K. Kertész E. Horváth I. E. Lukács L. P. Biró Z. E. Horváth 《Applied Physics A: Materials Science & Processing》2014,117(4):2107-2113
Chemical sensing properties of single wire and mat form sensor structures fabricated from the same carbon nanotubes (CNT) materials have been compared. Sensing properties of CNT sensors were evaluated upon electrical response in the presence of five vapours as acetone, acetic acid, ethanol, toluene, and water. Diverse behaviour of single wire CNT sensors was found, while the mat structures showed similar response for all the applied vapours. This indicates that the sensing mechanism of random CNT networks cannot be interpreted as a simple summation of the constituting individual CNT effects, but is associated with another robust phenomenon, localized presumably at CNT–CNT junctions, must be supposed. 相似文献