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31.
32.
Alexander Samokhvalov Eduardus C. Duin Sachin Nair Bruce J. Tatarchuk 《Surface and interface analysis : SIA》2010,42(9):1476-1482
The Ag/titania sorbent for the ultradeep desulfurization of liquid fuels was characterized by electron spin resonance and was found to contain nearly the stoichiometric titania, without significant concentration of Ti3+ or the reactive oxygen species. The surface chemical reactions of thiophene adsorbed on the Ag/titania were studied by temperature‐programmed XPS from 25 to 525 °C upon in situ thermal annealing in high vacuum and in situ oxidation by oxygen gas. The titania support is not chemically reactive under those conditions. Silver oxide in the Ag/titania sorbent is converted to Ag2 S without formation of the transient surface sulfates or sulfites and is further oxidized by molecular oxygen. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
33.
R. D. Bhanushali Sachin S. Pathak I. C. Pius S. K. Mukerjee 《Journal of Radioanalytical and Nuclear Chemistry》2010,284(3):647-651
Based on the Linssi database and UniSampo/Shaman software, an automated analysis platform has been setup for the analysis
of large amounts of gamma-spectra from the primary coolant monitoring systems of a CANDU reactor. Thus, a database inventory
of gaseous and volatile fission products in the primary coolant of a CANDU reactor has been established. This database is
comprised of 15,000 spectra of radioisotope analysis records. Records from the database inventory were retrieved by a specifically
designed data-mining module and subjected to further analysis. Results from the analysis were subsequently used to identify
the reactor coolant half-life of 135Xe and 133Xe, as well as the correlations of 135Xe and 88Kr activities. 相似文献
34.
Subtle differences in RNA and DNA duplex geometry could be sensed by the changed stereochemistry at 3'-amino function in the 5-atom thioacetamido linker of thioacetamido-linked nucleic acids and iso-thioacetamido-linked nucleic acids modified oligomers. In contrast to the preferred N-type sugar conformations for either 3'- ribo- or xylo amino nucleosides, predominant S-type sugar conformations were found in the dimers. Although the CD spectral differences for the dimer blocks were found to be identical for those found in phosphodiester linked ribo/xylo dimers, the 5-atom thioactamido linker could reverse the RNA binding selectivity to DNA binding selectivity by the change in configuration at the 3'-amino-substituted sugar. 相似文献
35.
Calculation of Channel Capacity Considering the Effect of Different Seasons for Higher Altitude Platform System 总被引:1,自引:1,他引:0
This paper presents effect of the weather impairments on a high altitude platform (HAP) broadband wireless communication system.
It is shown that attenuation due to oxygen, water vapor, fog, cloud, and rain has significant effect on a radio link which
is operating in a millimeter frequency range. Channel capacity is calculated for different seasons using Shannon’s channel
capacity theorem. The location of HAP is taken to be Delhi (India). Further, it is considered that a user and the HAP platform
are stationary. 相似文献
36.
The Er3+ -Yb3+ codoped in Li2O content tungsten -tellurite (TWL) transparent glasses are synthesized and measured the absorption, Raman and upconversion
luminescence (UPL) spectra. At room temperature intense green emission peak at 560 nm ( 4S3/2→4I15/2) and red emission peak at 670 nm ( 4F9/2→4I15/2) of Er3+ observed even at minimum 86 mW pumping power of infrared 980 nm excitation. For structure of the TWL glass, Raman spectrum
result revealed that an important role of WO3 in the formation of glass network linkage with Li2O. Under this influence estimated lifetime of the 4I11/2 of Er3+ was 1.89 μs and due to lower phonon energy of the glass produce strong upconversion signal. The effect of Er2O3 concentration on emission intensity result indicated that green emission intensity initially increase in compare to red emission.
Under the 980 nm pump power variation measured the relatively increases the red emission to the green emission intensity and
analyze the possible upconversion mechanism and process. 相似文献
37.
38.
JPC – Journal of Planar Chromatography – Modern TLC - A densitometric HPTLC method has been established for simultaneous quantification of sennosides A and B and gallic acid in a... 相似文献
39.
Sachin Bhalekar Varsha Daftardar‐Gejji 《Numerical Methods for Partial Differential Equations》2010,26(4):906-916
In this article, we apply the new iterative method proposed by Daftardar‐Gejji and Jafari (J Math Anal Appl 316, (2006), 753–763) for solving various linear and nonlinear evolution equations. The results obtained are compared with the results by existing methods. © 2009 Wiley Periodicals, Inc. Numer Methods Partial Differential Eq, 2010 相似文献
40.
4(3H)‐Quinazolinones were synthesized in high yields by one‐pot three‐component condensation of anthranilic acid, carboxylic acid and aniline in the presence of ionic liquid such as 1‐n‐butyl‐3‐methylimidazolium tetrafluoroborate (BMImBF4) as catalyst under solvent free and neutral conditions. 相似文献