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101.
We have analyzed the role of interaction range on multifragmentation within the isospin-dependent quantum molecular dynamic
(IQMD) model. We find that the effect of width of Gaussian wave packet associated with a nucleon depends on the mass of the
colliding system. For a given set of input parameters, we find that width has a sizable effect. At the same time, we know
that a different set of parameters can influence the reaction dynamics drastically. Hence, in our opinion it may not be possible
to pin down the width to a very narrow level. A systematic study of mass effect ( 197Au, 124La, 124Sn, 107Sn in the breakup of a projectile spectator at intermediate energies has been performed. We also studied the disapperance
of flow which demonstrates the effect of the scaled Gaussian width (SGW). Our studies shows that SGW influences the reaction
dynamics. 相似文献
102.
Microchimica Acta - New spot tests are described for the selective detection of Tl(I), Bi(III), and I? ions, with limits of detection 4 μg, 5 μg, and 15 μg respectively, and... 相似文献
103.
104.
The dc conductivity of semiconducting cobalt-phosphate glasses has been measured at temperatures ranging from 213 to 530 K. Four bulk samples of CoO-P2O5 glasses of different compositions were produced by melting dry mixtures of analytical reagent grades of CoO and P2O5 at temperatures between 1200-1250 °C for 2 h using a press-quenching method from glass melt. Samples were annealed at 400 °C for 1 h. The dc conductivity was found to be dependent on the CoO content in the glass. At temperatures from 213 to 444 K, however, both Mott's variable-range hopping (VRH) and the Greaves' intermediate range hopping models are found to be applicable. VRH at this range of temperatures is attributed to large values of the disorder energy of these glasses. 相似文献
105.
Prakash S. Nayak Sumati Anthal Vivek K. Gupta Rajni Kant H. S. Yathirajan 《Molecular Crystals and Liquid Crystals》2014,592(1):249-258
4-[(3-Acetylphenyl)amino]-2-methylidene-4-oxobutanoic acid (1) is synthesized by a ring opening reaction of itaconic anhydride with 3-aminoacetophenone and characterized by FT-IR, 1H NMR, UV-Vis, TGA, DTA, and single crystal X-ray diffraction. The crystal of 1 belongs to triclinic unit cell in the P-1 space group with the unit cell dimensions a = 4.9485(3), b = 5.3614(6), c = 22.457(2) Å, α = 88.295(8), β = 89.379(7), γ = 84.495(7), and Z = 2 The crystal structure is solved by direct methods using single-crystal X-ray diffraction data collected at room temperature and refined by full-matrix least-squares procedures to a final R-value of 0.0467 for 1623 observed reflections. Intermolecular N&;sbnd;H?…O and O&;sbnd;H?…O hydrogen bonds links the molecules into chains along [010] direction. In addition the thermal stability of the 1 is determined by using DTA, TGA analysis, and wavelength absorption at λmax = 297 nm is determined by UV-Vis spectrophotometer. 相似文献
106.
Charles J. Beischel Daniel R. Knapp Rajni Govindjee Thomas G. Ebrey Rosalie K. Crouch 《Photochemistry and photobiology》1994,60(1):64-68
Abstract —The retinal derivative, all-truns-9–(4-azido-2,3,5,6-tetrafluorophenyl)-3,7-dimethyl-2,4,6,8-nonatetraenal, was synthesized by two routes as a potential photoactivatable cross-linking agent for studies in bacteriorhodopsin (BR) of the chromophore interaction with its apoprotein. The retinal analogue formed a stable, moderately functional BR pigment confirming that the ring cavity of the retinal binding site has a significant tolerance for derivatization on that portion of the molecule. Attempts to cross-link the azido chromophore to the protein by photoactivation were unsuccessful. The electron delocalization effect of the conjugated polyene side chain of the retinal appears to interfere with the formation or reactivity of the nitrene intermediate to the extent that photoactivated cross-linking is not achieved. These results demonstrate a limitation to the use of fluorinated aryl azides as photoaffinity reagents. 相似文献
107.
Dielectric measurements on three heterocyclic compounds namely pyrrolidine, piperidine and 2-acetylpyridine in paraffin oil
and paraffin oil + cyclohexane mixtures over the temperature range (294–318 K) at 9.8 GHz have been made. The data have been
analysed using the method of Higasiet al and their dependence on macroscopic viscosity has been examined. The effect of solvent viscosity on the dipolar rotational
process of the molecules in highly viscous media is also discussed. 相似文献
108.
Galaeva IY Dainiak MB Plieva FM Hatti-Kaul R Mattiasson B 《Journal of chromatography. A》2005,1065(2):169-175
Two steps in parallel processing of multiple biosamples, namely, sample clarification and capture of the target protein, were integrated and combined with the direct assay of captured protein using a newly developed microtiter (96-well) plate system based on the monoliths of hydrophilic elastic supermacroporous material, cryogel. Cryogel monoliths have pore size large enough for microbial and mammalian cells to pass through unretained. Moreover, cryogel monoliths are elastic allowing them to be slightly compressed and easily introduced into the wells. When expanded, cryogel monoliths fill the well tightly with no risk of leakage in between the monolith and the walls of the well. The capillary forces keep the liquid inside the pores of the cryogel monolith making the monolith columns drainage protected. The application of a certain volume of liquid on top of a cryogel monolith column results in the displacement of exactly the same volume of liquid from the column. The concept of using supermacroporous gels in 96-well plate format offers new possibilities to the biotechnologist allowing separation of particulate matter, capturing of soluble material from particle containing media, and parallel assay of large number of non-clarified samples. 相似文献
109.
P. Singh S. V. L. S. Rao Rajni Pande T. Basak Shweta Roy M. Aslam P. Jain S. C. L. Srivastava Rajesh Kumar P. K. Nema S. Kailas V. C. Sahni 《Pramana》2007,68(2):331-342
At BARC, development of a Low Energy High Intensity Proton Accelerator (LEHIPA), as front-end injector of the 1 GeV accelerator
for the ADS programme, has been initiated. The major components of LEHIPA (20 MeV, 30 mA) are a 50 keV ECR ion source, a 3
MeV Radio Frequency Quadrupole (RFQ) and a 20 meV drift tube linac (DTL). The Low Energy Beam Transport (LEBT) and Medium
Energy Beam Transport (MEBT) lines match the beam from the ion source to RFQ and from RFQ to DTL respectively. Design of these
systems has been completed and fabrication of their prototypes has started. Physics studies of the 20–1000 MeV part of the
Linac are also in progress. In this paper, the present status of this project is presented.
相似文献
110.
In vivo progressive effects of UV irradiation on the lens epithelium were studied using various histomorphological and biochemical parameters. Fifteen day old rat pups were exposed to 600 mW/m2 of radiation, including UV-A and UV-B, 12 h daily for 90, 120, 150 and 180 days. Biochemical parameters such as protein-bound and non-protein-bound sulfhydryl groups in both soluble and insoluble fractions and enzymes, which play an important role in combating the oxidative stress, were studied. Decreased cell density of lens epithelial cells (LEC) was observed in all three zones along with the decrease in the levels of soluble sulfhydryls (S-SH), glutathione reductase (GR), superoxide dismutase (SOD), glutathione peroxidase (GPx) and catalase (CAT). On the other hand, an increase in insoluble sulfhydryls was observed. Because of the decrease in S-SH and GR activities, the LEC became vulnerable to oxidative stress. Decreased activities of SOD, GPx and CAT suggest elevated oxidative stress. This effect of UV radiation may lead to cell death that may be responsible for the observed decrease in the cell density in all three zones of the lens epithelium. 相似文献