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排序方式: 共有97条查询结果,搜索用时 672 毫秒
1.
2.
A. A. Naqvi Faris A. Al-Matouq F. Z. Khiari Khateeb-ur-Rehman M. A. Gondal A. A. Isab 《Journal of Radioanalytical and Nuclear Chemistry》2013,296(1):215-221
A thermal neutron capture-based Prompt Gamma ray Activation Analysis setup has been designed to analyze the elemental concentration of environmental bulk samples using a D(d,n) reaction-based portable neutron generator. The performance of the setup was tested through mercury concentration measurements in Hg-contaminated water samples using a large volume cylindrical bismuth germinate (BGO) gamma ray detector. Excellent agreement of experimental count rate of 2.64, 3.19 + 3.29 and 4.67–5.05 MeV Hg prompt gamma rays with theoretical count rate obtained through Monte Carlo simulations, indicates excellent performance of the newly designed portable neutron generator-based PGNAA setup. 相似文献
3.
Background
In this paper, the kinetics of oxidation of [CrIII(HIDA)(Val)(H2O)2]+ and [CrIII(HIDA)(Arg)(H2O)2]+ (HIDA = iminodiacetic acid, Val = DL-valine and Arg = L-arginine) were studied. The choice of ternary complexes was attributed to two considerations. Firstly, in order to study the effect of the secondary ligands DL-valine and L-arginine on the stability of binary complex [CrIII(HIDA)(IDA)(H2O)] towards oxidation. Secondly, transition metal ternary complexes have received particular focus and have been employed in mapping protein surfaces as probes for biological redox centers and in protein capture for both purification and study. 相似文献4.
K. El Aidoudi A. Qachaou M. Faris H. Lassri A. Fahmi Z. Yamkane 《Optical and Quantum Electronics》2013,45(10):1019-1026
In this work, we present a study of the magneto transport properties in magnetic multilayered structure $\text{ Ni }_{81}\text{ Fe }_{19}\text{/Zr }$ Ni 81 Fe 19 /Zr . The magnetic $(\text{ Ni }_{81}\text{ Fe }_{19})$ ( Ni 81 Fe 19 ) and non magnetic (Zr) layer thickness $(\mathbf{t}_\mathbf{NiFe}, \mathbf{t}_\mathbf{zr})$ ( t NiFe , t zr ) effects on the magneto resistance (MR) are discussed theoretically in the framework of the Johnson–Camley semi classical approach based on the Boltzmann transport equation. A comparison between calculated and measured MR is obtained. The observed MR ratio oscillates for Zr layer thickness with an average period of 7Å. A generally weak $\text{ MR }(\text{ t }_{\mathrm{NiFe}})$ MR ( t NiFe ) ratio for fixed $\mathbf{t}_\mathbf{zr}$ t zr is obtained and it shows a maxima peak of the MR with a value of 1.8 % located at $\mathbf{t}_\mathbf{NiFe}= 80$ t NiFe = 80 Å. 相似文献
5.
William G. Faris 《Communications in Mathematical Physics》1973,30(1):23-34
LetH
00 be a self-adjoint operator acting in a spaceL
2(M, ). It is assumed thatH
0
e=0, wheree is strictly positive, and that exp(–tH
0) is positivity preserving fort0. LetV be a real function onM such that its positive part is inL
2(M,e
2) and its negative part is relatively small with respect toH
0. ThenH=H
0+V is essentially self-adjoint on the intersection of the domains ofH
0 andV. This result is applied to Schrödinger operators and to quantum field Hamiltonians. 相似文献
6.
Theodor Kostiuk John J. Hillman James L. Faris 《Journal of Molecular Spectroscopy》1981,89(2):397-404
Precision measurements of 26 individual spectral lines of ozone near 9.5 μm were made using the GSFC infrared heterodyne spectrometer. The line profiles of 26 lines in near coincidence with the emission lines from a 12C16O2 laser local oscillator were measured at resolving powers of 6 × 106. The retrieved absolute line center frequencies, accurate to ±3 MHz, and the relative line intensities were compared to previous experimental results and theoretical calculations. 相似文献
7.
8.
Travnikova O Liu JC Lindblad A Nicolas C Söderström J Kimberg V Gel'mukhanov F Miron C 《Physical review letters》2010,105(23):233001
Dissociative nuclear motion in core-excited molecular states leads to a splitting of the fragment Auger lines: the Auger-Doppler effect. We present here for the first time experimental evidence for an Auger-Doppler effect following F1s → a(1g)* inner-shell excitation by circularly polarized x rays in SF(6). In spite of a uniform distribution of the dissociating S-F bonds near the polarization plane of the light, the intersection between the subpopulation of molecules selected by the core excitation with the cone of dissociation induces a strong anisotropy in the distribution of the S-F bonds that contributes to the scattering profile measured in the polarization plane. 相似文献
9.
10.
We have prepared and characterized several lanthanide ion complexes of multidentate ligands or chelates in an effort to develop new upconverting luminescent labels that can be immune to autofluorescence and photobleaching. This study has involved the characterization of various chelates of Nd, Er, and Tm with respect to relative luminescent efficiency and excited-state lifetimes and explored various two-photon stepwise excitation mechanisms. Using peak laser powers near 100 kW, the upconversion emissions of Nd in Nd(EDTA)2(5-) at 386 nm, Er in Er(DPA)3(3-) at 550 nm, and Tm in Tm(DPA)3(3-) at 480 nm, at levels of approximately 10(-12) moles can be detected. 相似文献