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141.
R. J. Peterson S. deBarros I. O. deSouza M. B. Gaspar Hameed Ahmed Khan Shahid Manzoor 《Zeitschrift für Physik A Hadrons and Nuclei》1995,352(2):181-189
Data for fission induced by pi meson beams from 80 to 500 MeV are presented for nuclei from Fe through Pu as measured by solid state track detectors. The general trends for binary fission withπ + are reproduced fairly well by a calculation in the ‘high excitation’ limit with standard level density and fission barrier parameters, butπ ? data are underpredicted. A universal dependence of the binary fission probabilities with the fissility (Z±1)2/A is found to be valid for both pion beam charges for all beam energies below the delta resonance. Probabilities for observing three fragments withπ + are not reproduced by a ternary fission application of the model found to work for binary fission. 相似文献
142.
143.
Ashleigh N. Bristol Brooke P. Carpenter Ashley N. Davis Lisa K. Kemp Vijayaraghavan Rangachari Shahid Karim Sarah E. Morgan 《Macromolecular bioscience》2020,20(8)
Gliadin, a component of gluten and a known epitope, is implicated in celiac disease (CeD) and results in an inflammatory response in CeD patients when consumed. Acrylamide‐based polyelectrolytes are employed as models to determine the effect of molecular weight and pendent group on non‐covalent interaction modes with gliadin in vitro. Poly(sodium 2‐acrylamido‐2‐methylpropane sulfonate) and poly(sodium 3‐methylpropyl‐3‐butanoate) are synthesized via aqueous reversible addition fragmentation chain transfer (aRAFT) polymerization and characterized by gel permeation chromatography‐multiangle laser light scattering. The polymer/gliadin blends are examined via circular dichroism, zeta potential measurements, 8‐anilinonaphthalene‐1‐sulfonic acid fluorescence spectroscopy, and dynamic light scattering. Acrylamide polymers containing strong anionic pendent groups have a profound effect on gliadin secondary structure and solution behavior below the isoelectric point, while polymers containing hydrophobic character only have a minor impact. The polymers have little effect on gliadin secondary structure and solution behavior at the isoelectric point. 相似文献
144.
We consider a two-photon correlated emission laser as a source of an entangled radiation with a large number of photons in each mode. The system consists of three-level atomic schemes inside a doubly resonant cavity. We study the dynamics of this system in the presence of cavity losses, concluding that the creation of entangled states with photon numbers up to tens of thousands seems achievable. 相似文献
145.
We show that a particle confined in a one-dimensional square well in the presence of an external periodic linear modulation
undergoes coherent oscillations between the discrete levels analogous to an atom exposed to an electromagnetic field. We define
the selection rules for state transitions based on the matrix elements of the perturbation potential. These selection rules
contribute to the time evolution of the qubit which can partake efficiently in quantum informatics. Quantum logic gates are
realized in the square-well potential by controlling the period of modulation. 相似文献
146.
S.?AhmadEmail author S.?A.?Janjua Shahid?Hussain A.?Ellahi 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2003,22(2):189-192
Certain important and pertinent questions have been raised by E. Träbert in his comment on the paper [Eur. Phys. J. D 22, 189 (2003)] by one of us. We provide explanations as well as new and recent data using a calibrated monochromator on the existence of the main intercombination multiplet 233 nm which is the bone of contention. It is shown that there is no conflict with the established atomic physics in the regenerative sooting discharges; only the interpretations are at variance with those of the comment.Received: 30 July 2003, Published online: 30 September 2003PACS:
32.70.Fw Absolute and relative intensities - 34.50.Dy Interactions of atoms and molecules with surfaces; photon and electron emission; neutralization of ions - 34.80.Dp Atomic excitation and ionization by electron impact 相似文献
147.
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149.
A simple, selective, sensitive, precise, simultaneous high performance liquid chromatographic analysis of serum samples and commercial tablet formulation containing hydrochlorothiazide, olmesartan medoxomil and irbesartan are reported. Good chromatographic separation was achieved using a μ-Bondapak, C18 column (15 cm×4.6 mm, 5 μm), and a mobile phase consisting of acetonitrile-0.2% acetic acid aqueous solution (50∶50, v/v) at a flow rate of 1.0 mL/min. The ultraviolet detector was set at a wavelength of 260 nm. Hydrochlorothiazide, olmesartan medoxomil, and irbesartan were eluted at 1.2, 3.8, and 4.4 min, respectively. No extraneous materials were found to interfere. The method uses protein precipitation with acetonitrile for the preparation of serum sample. The linear ranges for hydrochlorothiazide, olmesartan medoxomil, and irbesartan were 6.25-18.75, 20-60, and 75-225 ng/mL, respectively. The recoveries of hydrochlorothiazide, olmesartan medoxomil, and irbesartan in spiked samples were all greater than 98%, and their relative standard deviations were less than 2.0%. The limits of detection were 1, 2, and 2 ng/mL for hydrochlorothiazide, olmesartan medoxomil, and irbesartan, respectively, and the limits of quantification were 3 ng/mL, which allow their determination at the expected serum concentration levels. 相似文献