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101.
Abstract FT-IR spectroscopy has been employed in the detection of the carbonyl absorption band centered at 1728 cm?1 and assigned to the open form of D-fructose in deuterium oxide or water. Changes in the intensity of the band at 1728 cm?1 allowed the monitoring of the concentration of the open form of the keto sugar D-fructose at different temperatures and pHs. The concentration of the open form was observed to increase with increasing temperature and was an order of magnitude higher at 80 °C compared to 30 °C. The buildup of the open form was found to be extremely rapid. The new equilibrium can be reversed with decreasing temperature with a slight hysteresis. This work demonstrates the potential of applying FT-IR spectroscopy in studying the effect of environmental factors on the level of the open chain form of sugars. 相似文献
102.
Y. G. Shee M. A. Mahdi M. H. Al-Mansoori A. Ismail N. A. M. A. Hambali A. K. Zamzuri R. Mohamad S. Yaakob 《Laser Physics》2009,19(12):2194-2196
A simple configuration for the reduction of stimulated Brillouin scattering threshold in photonic crystal fiber is presented.
The threshold reduction is contributed by the bidirectional pumping scheme through the reflection of transmitted Brillouin
pump back to the gain medium. The pump recycling scheme has greatly reduced the Brillouin threshold of a 200-m long of photonic
crystal fiber from 50 to 30 mW of Brillouin pump power. 相似文献
103.
Understanding CHF is of an upmost importance in many industries, especially in the design and operation of boilers, nuclear power plants, cryogenic systems, etc. Due to safety issues related to the nuclear power plants, and the adaptation of CHF as the limiting criterion of power generation, it is important to understand the mechanisms of CHF relevant to nuclear systems operation. Moreover, CHF is expected to occur during transients than steady-state conditions. Therefore, knowledge of transient CHF is of great importance for the safety evaluation of nuclear reactors under transient condition. In this paper, the existing CHF experimental and modeling studies are discussed in order to understand the phenomena leading to CHF. Also, the effect of transient conditions on CHF for nuclear fuels has been evaluated. 相似文献
104.
M. K. Kullab B. A. Al-Bataina A. M. Ismail K. M. Abumurad 《Radiation measurements》2001,34(1-6):361-364
Previously calibrated passive detectors (CR-39) and an active radon device (Radon Monitor RM3) were used to study seasonal variation of radon-222 concentration levels inside and outside specific locations in Jordan. The study sites were located in an area that used to be an old phosphate mine. We found that the maximum value of radon concentration in air inside the dwellings, as measured by the passive dosimeters, was 1532.9 Bq/m3 during the winter season, and the minimum one was 46.3 Bq/m3 during fall season. While the highest and lowest readings of the active monitor were 892 and 4 Bq/m3 during fall and summer seasons, respectively. The radon concentration in soil ranges from 0.2 kBq/m3 in spring to 37.8 kBq/m3 in fall. 相似文献
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108.
The structure of the 2-thiazolylazosalicylic acid molecule, TAS, has been determined by means of quantum SCF-CI calculations. The ionization potential and the electron affinity of TAS molecule were calculated to have the values 9.057 and 2.56 eV respectively. The solvation energies in different solvents, and the bond orders of the TAS molecule were calculated for the neutral state, the oxidized form (the cation) and the reduced form (the anion). Mixed solvent studies were carried out with TAS and 2-benzothiazolylazosalicylic acid (BTAS), using polar solvents (EtOH and MeOH) to confirm the formation of a solvent-solute complex. The azo group in the TAS molecule nas a considerable contribution in the SCFLUMO; thus cathodic reduction has been focused on the azo group and was verified experimentally by cathodic reduction. 相似文献
109.
Amand Faessler M. Ismail N. Ohtsuka M. Rashdan W. Wadia 《Zeitschrift für Physik A Hadrons and Nuclei》1987,326(4):501-508
A recent approach for calculating both the real and imaginary parts of the ion-ion potential has been modified to produce the ground state properties of separate nuclei. This approach is used to study both the energy and orientation dependence of the optical potential between two U nuclei adopting the sudden and adiabatic approximations. 相似文献
110.
Ismail A. Haj Waseem Hafiz Muhammad Ishtiaq Muhammad Jamal Sajjad Shaukat Khan Majid 《International Journal of Theoretical Physics》2021,60(5):1720-1741
International Journal of Theoretical Physics - Most of the enciphering structures are based on the transformation of mediums by describing the strict criteria. The presented article is based on... 相似文献