2,007 research outputs found
Internal conversion coefficients for M4 transition for tellurium
Internal conversion coefficients for M4 transition in telluriu
TABLE OF ELECTRON WAVE FUNCTIONS AT THE NUCLEAR SURFACE
The beta and gamma radiations of 21-hr I/sup 133/ were investigated by single-crystal and multicrystal scintillation spectrometers, and a scheme is proposed for the energy levels of Xe/sup 133/. The level scheme of Ge/sup 74/ was obtained by means of single-crystal and multicrystal beta- and gammaray spectrometry using sources of Ga/sup 74/ and As/sup 74/. The angular correlation for the 0.60-0.60-Mev cascade was measured. Both beta- and gamma-ray single- crystal measurements and gamma-beta and gamma-gamma coincidence experiments were performed on the decay of I/sup 132/. Also, gamma-gamma angular correlations were measured for all the prominent gamma rays. This information has led to a level scheme in Xe/sup 132/ involving excited states at 0.673, signments of 2, 4, 3, and 4 for the first four of these. A study of 2.7-hr Pm/sup 150/ established that the most energetic beta ray, at 3.16 plus or minus 0.11 Mev, decays to the first excited state of Sm/sup 150/ at 0.333 Mev. A partial decay scheme based on beta-gamma coincidence spectrometry was formulated with excited states in Sm/sup 150/ at 0.333, 1.18, 1.66, and 2.08 Mev. The measurement of the neutron- absorption cross sections of Ce/sup 141/ and Ce/sup 144/ by the activation method is in progress. Separation of the 5.9-hr Pr/sup 145/ daughter of the 3-min Ce/ sup 145/ produced by the (n, gamma ) reaction on Ce/sup 144/ from the associated cerium isotopes was accomplished by the extraction of tetravalent cerium with di(2-ethyl-hexyl)phosphoric acid in n-heptane. Preliminary results of several irradiations of Ce/sup 144/ in the LITR indicate an effective neutron cross section of (6 plus or minus 2) x 10/sup -24/ cm/sup 2/atom. Flux depressions in the vicintty of and within infinite cadmium slabs were calculated using the SNG reactor code on the IBM-704 computer at K-25. These results are pertinent to burnout calculations concerning cadmium filters during long irradiations. An upper limit of 0.1 barn was set for the formation cross section of the 25-sec isomer of Po/sup 211/ from Po/sup 210/ for thermal reactor neutrons. An upper limit of about 7 x 10/sup 5/ years was obtained for the haif life of Bi/sup 208/ by measuring the disintegration rate and measuring qualitatively the Bi/sup 208/ Bi/sup 209/ ratio; this value is consistent with an approximate estimate of 7.5 x 10/sup 5/ years by C. H. Miller and co-workers at Chalk River. A value of 870 barns was determined for the fission resonance integral of U/sup 233/ from analyses of three fission products: Sr/sup 89/, Mo/sup 99/, and Ba/sup 140 /. This value may be compared with two values, 900 and 820 barns, calculated from available resonance data. Work on electron depolarization by scattering and the effect of multiple scattering on scattering asymmetry, along with changes in experimental equipment, will allow the use of weaker sources in beta-ray polarization measurements. (auth
Quantum Hamilton-Jacobi analysis of PT symmetric Hamiltonians
We apply the quantum Hamilton-Jacobi formalism, naturally defined in the
complex domain, to a number of complex Hamiltonians, characterized by discrete
parity and time reversal (PT) symmetries and obtain their eigenvalues and
eigenfunctions. Examples of both quasi-exactly and exactly solvable potentials
are analyzed and the subtle differences, in the singularity structures of their
quantum momentum functions, are pointed out. The role of the PT symmetry in the
complex domain is also illustrated.Comment: 11 page
Dielectronic Recombination on and Electron-Impact Excitation of Heliumlike Argon
We have measured cross sections for Δn=1 dielectronic recombination (DR) on He-like argon and found good agreement with theoretical calculations based on the Hartree-Fock atomic model. Experimental absolute cross sections were obtained by using the electron-energy dependence of yields of He-like and Li-like argon ions from the Kansas State University electron-beam ion source to measure the ratio of the DR cross section on He-like argon to the electron-impact-ionization cross section of Li-like argon and normalizing to the latter. The K x-ray emission spectra due to Δn=1,2 DR and n=1→2 electron-impact excitation of He-like argon were also observed with a Si(Li) detector placed at 0° relative to the electron-beam direction. By normalizing to the theoretical KLL integrated DR differential cross section, we obtained differential and partial differential DR cross sections and differential electron-impact excitation cross sections. We found good agreement with Hartree-Fock calculations for DR and with distorted-wave calculations for electron-impact excitation
Recommended from our members
NBS monograph
From Introduction: "This Monograph, supplemented by ORNL-3207 [9], should eliminate completely the need for use of approximate formulas (e.g. those of Kotani and Ross [10]). The formulation of the problem has been summarized in sec. II. This is followed in sec. III by a discussion of the methods used in numerical calculations. Sec. IV contains a detailed explanation to facilitate the use of present tables.
Recommended from our members
Laboratory Measurements of Fe XXIV Line Emission: 3→2 Transitions Near Excitation Threshold
Using the Electron Beam Ion Trap facility at Lawrence Livermore National Laboratory, we have measured relative cross sections for Fe XXIV line emission at electron energies between 0.7 and 3.0 keV. The measurements include line formation by direct electron impact excitation (DE), radiative cascades, resonant excitation (RE), and dielectronic recombination (DR) satellites with captured electrons in n≥5 levels. Good agreement with R-matrix and distorted wave calculations is found. In collisionally ionized plasmas, at temperatures near where the ion abundance peaks (kTe~1.7 keV), the RE contributions are found to be ≲5% of the line emission, while the DR satellites contribute ≲10%. While good agreement with state-of-the-art atomic physics calculations is found, there is less good agreement with existing spectral synthesis codes in common astrophysical use. For the Fe XXIV 3p3/2 → 2s1/2, 3p1/2 → 2s1/2, and 3d5/2 → 2p3/2 transitions, the synthesis code MEKAL underestimates the emissivity in coronal equilibrium by ~20% at temperatures near where the ion abundance peaks. In situations where the ionization balance is not solely determined by the electron temperature, RE and DR satellites may contribute a considerable fraction of the line emission
Enhanced Room Temperature Coefficient of Resistance and Magneto-resistance of Ag-added La0.7Ca0.3-xBaxMnO3 Composites
In this paper we report an enhanced temperature coefficient of resistance
(TCR) close to room temperature in La0.7Ca0.3-xBaxMnO3 + Agy (x = 0.10, 0.15
and y = 0.0 to 0.40) (LCBMO+Ag) composite manganites. The observed enhancement
of TCR is attributed to the grain growth and opening of new conducting channels
in the composites. Ag addition has also been found to enhance intra-granular
magneto-resistance. Inter-granular MR, however, is seen to decrease with Ag
addition. The enhanced TCR and MR at / near room temperature open up the
possibility of the use of such materials as infrared bolometric and magnetic
field sensors respectively.Comment: 22 pages of Text +
Figs:comments/suggestions([email protected]
Green competence framework: Evidence from China
© 2015 Taylor & Francis Recently human resources management functions such as recruitment, selection, training and performance evaluation are expected in considering environmental management issues. Environmental protective acts with adequate ecological knowledge and socio-economic behavior and skills are referred to in this paper as green competencies (GCs). However, a systematic approach for developing and understanding key factors that enhance individuals' GCs is lacking. This study contributes to green human resource literature by integrating environmental consumer behavior literature with traditional skills and competencies literature to help firms to select the right individuals to achieve their environmental goals. Using Robert's competencies framework and structural equation modeling, this paper empirically examines the influence of individual GCs on organizations' green practices and performance objectives. Our model is tested using a sample of 1230 employees working in key industries in the Chinese coastal city of Ningbo. The results indicate that acquired GCs are more positively associated with individuals' GCs and green behavior. The study empirically demonstrates that verifying acquired GC attributes such as environmental knowledge, green purchase attitude and intention during employee selection would certainly be helpful for firms to identify individual green performance potential
A guanosine 5′-triphosphate-dependent protein kinase is localized in the outer envelope membrane of pea chloroplasts
A guanosine 5-triphosphate (GTP)-dependent protein kinase was detected in preparations of outer chloroplast envelope membranes of pea (Pisum sativum L.) chloroplasts. The protein-kinase activity was capable of phosphorylating several envelope-membrane proteins. The major phosphorylated products were 23- and 32.5-kilo-dalton proteins of the outer envelope membrane. Several other envelope proteins were labeled to a lesser extent. Following acid hydrolysis of the labeled proteins, most of the label was detected as phosphoserine with only minor amounts detected as phosphothreonine. Several criteria were used to distinguish the GTP-dependent protein kinase from an ATP-dependent kinase also present in the outer envelope membrane. The ATP-dependent kinase phosphorylated a very different set of envelope-membrane proteins. Heparin inhibited the GTP-dependent kinase but had little effect upon the ATP-dependent enzyme. The GTP-dependent enzyme accepted phosvitin as an external protein substrate whereas the ATP-dependent enzyme did not. The outer membrane of the chloroplast envelope also contained a phosphotransferase capable of transferring labeled phosphate from [-32P]GTP to ADP to yield (-32P]ATP. Consequently, addition of ADP to a GTP-dependent protein-kinase assay resulted in a switch in the pattern of labeled products from that seen with GTP to that typically seen with ATP
- …