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91.
K.B. Bhalla M. Chaudhry S. Lokanathan R.K. Grover I.K. Daftari G.L. Kaul L.K. Magotra Y. Prakash N.K. Rao S. Garpman I. Otterlund 《Nuclear Physics A》1981,367(3):446-458
Relativistic α-particles have been studied in 423 interactions of Fe in emulsion at 1.7A GeV. Comparisons of the observed angular distribution with that from 16O-emulsion reactions at 2.1A GeV reveal that more α-particles are observed at large angles in the Fe-emulsion reactions. The α-particles at large angles cannot be explained by fragmentation from a clean-cut spectator. Comparison of the experimental data with moving relativistic Boltzmann distributions shows that a single Boltzmann distribution cannot fit the fragmentation peak and the tail simultaneously. A thermal source (fireball) explaining the tail part of the distribution needs to be formed by a mechanism other than a simple clean-cut participant-spectator process. A large transverse momentum transfer to the spectator before fragmentation may explain the tail. 相似文献
92.
The 1s22s2p J = 2 → J = 1 M1 transition rates are calculated in the multi-configuration Hartree-Fock procedure for several members of the beryllium isoelectronic sequence. The total transition rates, including existing M2 rates, are presented for different atomic numbers. 相似文献
93.
A study of 100 interactions, produced by secondary particles from 200 GeV/c proton interactions in nuclear emulsions, has
been made to estimate the transverse momenta of the secondary particles. The data have been analysed by different methods
of energy estimation and the weighted average values ofp
t
have been compared as estimated from various methods. An average value ofp
t
equal to 0.38 ± 0.03 GeV/c, in proton-nucleus interactions at 200 GeV/c, has been obtained from the production mechanism
method. 相似文献
94.
Mrinal Kumar Das Radhey Shyam Sharma Vandana Mishra 《Applied biochemistry and biotechnology》2012,166(6):1552-1561
Apoptotic cell death is a fundamental process in the development and physiological homeostasis of multicellular organisms.
It is associated with control of cell numbers in tissues and organs during development, with cell turnover, and with response
to infection. Molecules that trigger this process in continuously proliferating cancer cells can be used as chemotherapeutic
agents. Ribosome inactivating proteins (RIPs) that inhibit translation in a cell by depurinating (N-glycosidase activity) the 28S rRNA are known to serve as apoptosis inducers. However, the role of depurination activity of
the RIPs in apoptosis induction is still controversial. Presently, there are three different hypotheses which propose that
depurination is: (1) essential, (2) essential but not the sole factor, or (3) not essential for apoptosis induction. This
article reviews various experimental outcomes on the importance of N-glycosidase activity of RIPs in the induction of apoptosis. 相似文献
95.
Kansal Munish Cordero Alicia Bhalla Sonia Torregrosa Juan R. 《Numerical Algorithms》2021,87(3):1017-1060
Numerical Algorithms - In this paper, a two-step class of fourth-order iterative methods for solving systems of nonlinear equations is presented. We further extend the two-step class to establish a... 相似文献
96.
An efficient and operationally simple route to benzylseleno‐ and phenylselenoalkanoic acids from ethyl benzyl/phenylselenoalkanoates is described. This involves preparation of ethyl benzyl/phenylselenoalkanoates as substrates by reaction of dibenzyl/diphenyl diselenide and sodium borohydride with ethyl chloroalkanoates in ethanol followed by basic hydrolysis and subsequent acidification. 相似文献
97.
Iodine–ammonium acetate–mediated annealation of dimedone with aldehydes led to facile formation of spirodihydrofuran in good yields through tandem Knoevenagel–Michael iodonation and cyclodehydroiodonation reactions in a single pot. 相似文献
98.
In the present paper, we have executed the synthesis of substituted 5-(2-chloroquinolin-3-yl)-3-phenyl-4,5-dihydroisoxazolines via the reactions of substituted 3-(2-chloroquinolin-3-yl)-1-phenylprop-2-en-1-ones with hydroxylamine hydrochloride and sodium acetate in aqueous acetic acid solution in 72-90% yields at room temperature under ultrasound irradiation. This method provides several advantages such as operational simplicity, higher yield, safety and environment friendly protocol. The resulting substituted isoxazolines were characterized on the basis of (1)H NMR, (13)C NMR, IR, elemental analysis, and mass spectral data. 相似文献
99.
100.
The usually allowed Coster-Kronig L1L2,3M transitions are found not to be energetically possible for all electronic configurations with a single K-shell and multiple L-shell vacancies of Al. Consideration of these effects as related to X-ray measurements in heavy-ion-atom collisions are presented. 相似文献