Total conversion coefficient of the 263 keV (21+/2→13+/2) transition in93mMo

1985 ◽  
Vol 85 (1) ◽  
pp. 31-36 ◽  
Author(s):  
Ch. Suryanarayana ◽  
M. Venkateswara Rao ◽  
D. G. S. Narayana ◽  
S. Bhuloka Reddy ◽  
G. Satyanarayana ◽  
...  
1962 ◽  
Vol 40 (4) ◽  
pp. 383-392 ◽  
Author(s):  
J. G. V. Taylor

Using a new coincidence method, the total internal conversion coefficient for the 279-kev transition following the β-decay of Hg203 has been measured with a standard deviation of about 1%. The method which employs a 4πβ–γ coincidence arrangement is based on the differential absorption of β-particles and conversion electrons in 4π geometry. For determining the absolute efficiencies of γ-ray spectrometers or ion-chambers, the method has the advantage of yielding directly the number of γ-ray quanta emitted per Hg203 disintegration without requiring any knowledge of the K:L:M conversion ratios. Likely sources of systematic error have been investigated and their effect has been shown to be smaller than the quoted standard deviation. The value obtained is α = 0.2262 ±.0019 or γ/β = 0.8155 ±.0015, in excellent agreement with the recent β-ray spectrometer measurements of Nijgh et al. This is of interest because a number of widely differing values of conversion coefficients for this transition have been reported. If the K/(L+M+N) conversion ratio of 2.60 ±.06 found by Nijgh et al. is combined with our total conversion coefficient, a value αK = 0.1633 ±.0017 is obtained.


2018 ◽  
pp. 40-47
Author(s):  
D. I. Volkhin ◽  
G. N. Devyatkov

The development of a new class of broadband matching devices, including active impedance transformers, with the possibility of correcting the phase response is an actual task at present. Synthesis of a broadband active impedance transformer with a phase response corresponding to a second-order lattice X-section in a distributed elemental basis based on the previously presented method for the synthesis of broadband matching devices with predetermined phase response is considered in this paper. As a result of synthesis, the y-matrix of the broadband transforming two-port network is obtained. The functions of its own parameters represented in the form of Foster. Applying various conditions of circuit realizability in the synthesis process, we obtained structures convenient for realization on microwave on regular transmission lines, one of which is investigated at various parameters of a given phase response. As a result of the research, it is found that the structure has a wide ability to reproduce the phase response of a second-order lattice X-section with different parameters, and also reproduce the linear phase response characteristic while maintaining an acceptable level of the power conversion coefficient in a given frequency band. Thus, the efficiency of the previously proposed method of synthesis of broadband matching devices with predetermined phase response is demonstrated, and also the possibilities of active impedance transformers on regular transmission lines are shown.


1989 ◽  
Vol 54 (8) ◽  
pp. 2054-2063 ◽  
Author(s):  
Jiří Čejka ◽  
Ludmila Kubelková ◽  
Pavel Jírů

Acetone transformation catalyzed by HZSM-5 and NaZSM-5 zeolites and by zeolites modified with basic oxides was studied in an integral reactor at a temperature of 350 °C. Modification of acido-basic properties of ZSM-5 zeolites resulted both in the total conversion changes and in the essential changes in the product composition. Isobutene was found to be the main product over HZSM-5 zeolites exhibiting low activity, while aromatics prevailed when high conversion level was attained. Classical condensation of acetone yielding mesityloxide and phorones was observed over NaZSM-5 zeolites impregnated with CaO and ZnO.


1960 ◽  
Vol 38 (12) ◽  
pp. 1577-1585 ◽  
Author(s):  
Agda Artna ◽  
Margaret E. Law

The 52.8-hour activity of Pm149 has been investigated using a high resolution beta spectrometer, a lens type coincidence spectrometer, and a scintillation spectrometer in conjunction with a multichannel analyzer. The beta spectrum was found to consist of two groups with maximum energies of 1.072 ± 0.002 Mev and 0.786 ± 0.004 Mev, and intensities of 97.1 ± 0.4% and 2.9 ± 0.4% respectively. A gamma ray of energy 285.7 ± 0.3 kev was found to be in coincidence with the 0.786-Mev beta group. No other gamma rays with intensities greater than 0.1% were found. The K conversion coefficient for the 286-kev transition was measured to be 0.075 ± 0.008. This together with the values of 6.5 ± 0.7 and 4 ± 1 obtained for the K/L and L/M conversion ratios respectively indicate that this transition is M1 in character with less than 10% E2 admixture.


1983 ◽  
Vol 78 (4) ◽  
pp. 444-450 ◽  
Author(s):  
V. Lakshminarayana ◽  
T. T. Neo ◽  
S. M. Tang ◽  
A. Rajaratnam

Author(s):  
A. V Cherepkov ◽  
I. V. Konoshin

Grain before feeding to animals exposed to grinding with the purpose of increasing its digestibility. As a result of this increases the area of interaction of the feed with the gastric juice and decreases the conversion coefficient. Surface theory formulated by German scientist Rittinger, suggests that the work of AR required for the grinding process is directly proportional to newly formed surface. The purpose of this paper is a theoretical evaluation of the intensity of grinding with the use of sieves with rectangular and circular shape holes. When getting groats with the same grinding module by the use of sieves with holes of rectangular shape, one should expect the decrease of specific energy intensity. By reducing the content of dust-like fractions and reduce the total surface feed should be expected to reduce the energy intensity of pneumo transportation.


Sign in / Sign up

Export Citation Format

Share Document