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51.
52.
Hasan M. Khan Shagufta Naz Safia Tabassum 《Journal of Radioanalytical and Nuclear Chemistry》2011,289(1):225-229
Aqueous solution of crystal violet has been evaluated spectrophotometrically as a gamma-ray chemical dosimeter. The response
of the chemical dosimetric system has also been investigated under different environmental conditions, such as light and temperature.
In the present study the response has been measured at two wavelengths; 588 nm (λmax of the irradiated solution) and 500 nm. The response of the crystal violet dosimeter was linear in the dose range of 50–550 Gy
at pH 5.6 when absorption measurements were made at 588 and 500 nm. The response of the crystal violet dosimeter during post-irradiation
storage at room temperature in dark showed slight decrease in absorbance at 588 and 510 nm but the response was almost stable
at 460 nm. For higher doses, the change in the response was greater as compared to the low doses. Post-irradiation stability
during diffused sunlight showed significant decrease in the response for higher dose at 588 and 510 nm and slower decrease
in the response for lower dose at the above mentioned wavelengths. However the response was almost stable up to 97 days at
460 nm for higher and lower doses. At 4 °C, the decrease in the absorbance was slower at 588 and 510 nm while the response
was almost constant at 460 nm. At higher temperatures, such as 40 °C, the decrease in the absorbance was greater at 588 and
510 nm while at 460 nm the absorbance was almost constant for about 3 months. 相似文献
53.
A conformational study of the biomolecules released from submicron- and micron-sized temperature-sensitive composite polymer
particles by decreasing the temperature from 40 to 25 °C was done with circular dichroism and the results were compared with
those of the native biomolecules. In almost all cases the biomolecules released retained their native conformational states.
Received: 10 April 2001 Accepted: 13 June 2001 相似文献
54.
Hasan Kara Muhammad Aamir Ali Hüseyin Budak 《Mathematical Methods in the Applied Sciences》2021,44(1):104-123
In this paper, we define interval‐valued left‐sided and right‐sided generalized fractional double integrals. We establish inequalities of Hermite‐Hadamard like for coordinated interval‐valued convex functions by applying our newly defined integrals. 相似文献
55.
The Zinc Selenide (ZnSe) thin films have been deposited on SnO2/glass substrates by a simple and inexpensive chemical bath deposition (CBD). The structural, optical and electrical properties of ZnSe films have been characterized by X-ray diffraction (XRD), Energy Dispersive X-ray Analysis (EDAX), optical absorption spectroscopy, and four point probe techniques, respectively. The films have been subjected to different annealing temperature in Argon (Ar) atmosphere. An increase in annealing temperature does not cause a complete phase transformation whereas it affects the crystallite size, dislocation density and strain. The optical band gap (Eg) of the as-deposited film is estimated to be 3.08 eV and decreases with increasing annealing temperature down to 2.43 eV at 773 K. The as-deposited and annealed films show typical semiconducting behaviour, dρ/dT > 0. Interestingly, the films annealed at 373 K, 473 K, and 573 K show two distinct temperature dependent regions of electrical resistivity; exponential region at high temperature, linear region at low temperature. The temperature at which the transition takes place from exponential to linear region strongly depends on the annealing temperature. 相似文献
56.
We discuss the parametrization of quantum groups in terms of independent operators. We find that this consideration leads to the parametrization ofSU q(2) in terms of aq-oscillator plus a commuting phase. The commuting phase is naturally identified with the subgroupU(1) and the remaining cosetSU q(2)/U(1)=CP q(1) consists of aq-oscillator. For unitary quantum groupsSU q (n), the analogous construction results in the quantum projective spaceSU q(n+1)/U q (n)=CP q (n) being identified with then-dimensionalq-oscillator. This yields a nonlinear action of the quantum groupSU q(n+1) on then-dimensionalq-oscillator. 相似文献
57.
A. Konjhodzic A. Adamczyk F. Vagizov Z. Hasan E E. Alp W. Sturhahn Jiyong Zhao J J. Carroll 《Hyperfine Interactions》2006,170(1-3):83-89
With the decrease in size of devices, rapid characterization of nano-devices is an inevitable necessity. It is shown that Mössbauer spectroscopy using synchrotron radiation from the advanced photon source provides such a tool of investigation. Results are presented and compared for conventional Mössbauer and Nuclear Forward Scattering for 151Eu-doped magnesium sulfide as an example, especially at low concentrations. 相似文献
58.
Flat plates, both single and in tandem or side by side arrangement, are widely used in many engineering applications. Despite vast investigations of the flow structures and wakes downstream of these bluff bodies, this unsteady phenomenon yet remains a fundamental issue in many industrial applications. This paper reviews the state of the art concerning the flow over flat plates in different arrangements focusing on plates normal to the flow. Turbulent wake regions are discussed for the flat plates in side by side or tandem arrangement. Numerical studies are reviewed with emphasis on the realized turbulent models. The effect of the chosen turbulence model on the prediction of the wake region is discussed. 相似文献
59.
Najjar Morvarid Hosseini Hasan Ali Masoudi Abdolhossein Hashemzadeh Alireza Darroudi Majid 《Research on Chemical Intermediates》2020,46(4):2155-2168
Research on Chemical Intermediates - In this research, tin oxide nanoparticles (SnO2-nanoparticles) are synthesized using sol–gel method in polymeric bed and considering the principals of... 相似文献