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71.
M. Lakrimi S. Khym D. M. Symons R. J. Nicholas F. M. Peeters N. J. Mason P. J. Walker 《Physica E: Low-dimensional Systems and Nanostructures》1998,2(1-4)
We have studied the temperature dependence of the magnetoresistance of semimetallic InAs/GaSb structures with magnetic field applied parallel to the layers. We present the first unambiguous evidence for the presence of a mini-gap at the crossing point between the electron and hole dispersion relations. The resistivity is found to change from semiconductor-like behaviour with a strong temperature dependence at low parallel magnetic fields to that of a semimetal with a weak temperature dependence at high field. Furthermore, the magnetoresistance, for intrinsic samples, is found to decrease with field by as much as 70% at low temperatures. As the parallel magnetic field is increased the centres of the electron and hole dispersions are shifted apart in k-space and at sufficiently high field the mini-gap is destroyed and the bands overlap fully. Finally, a theoretical model allows us to estimate that the mini-gap is of order 7 meV. 相似文献
72.
Spectrophotometric evidence for the formation of contact ion-pairs in solutions of tetra-alkylammonium iodides in certain solvents of poor ion-solvating power, such as carbon tetrachloride, is presented. Since the band ascribed to contact ion-pairs is not detected for solutions in other solvents, such as chloroform, it is concluded that the ion-pairs detectable by other techniques in such solvents are separated by solvent molecules. 相似文献
73.
Mohammad T. Freigoun Penghong Guo Emily E. Hohman Alison D. Gernand Danielle Symons Downs 《Mathematical and Computer Modelling of Dynamical Systems: Methods, Tools and Applications in Engineering and Related Sciences》2013,19(6):661-687
ABSTRACTThe underlying mechanisms for how maternal perinatal obesity and intrauterine environment influence foetal development are not well understood and thus require further understanding. In this paper, energy balance concepts are used to develop a comprehensive dynamical systems model for foetal growth that illustrates how maternal factors (energy intake and physical activity) influence foetal weight and related components (fat mass, fat-free mass, and placental volume) over time. The model is estimated from intensive measurements of foetal weight and placental volume obtained as part of Healthy Mom Zone (HMZ), a novel intervention for managing gestational weight gain in obese/overweight women. The overall result of the modelling procedure is a parsimonious system of equations that reliably predicts foetal weight gain and birth weight based on a sensible number of assessments. This model can inform clinical care recommendations as well as how adaptive interventions, such as HMZ, can influence foetal growth and birth outcomes. 相似文献
74.
A radical exhibiting a very large hyperfine coupling to 127I, together with a small coupling to 14N, formed in γ-irradiated N-iodosuccinimide at 77 K is identified as a σ* radical anion in which the added electron is accommodated primarily in the N-I antibonding σ-orbital. 相似文献
75.
76.
ZHENG Yong-Nan ZHOU Dong-Mei K. Matsuta M. Mihara M. Fukuda D. Nishimura J. Komurasaki D. Ishikawa R. Matsumiya T. Nagatomo T. Izumikawa S. Takahashi H. Hirano T. Ohtsubo S. Momota Y. Nojiri A. Kitagawa M. Kanazawa M. Torikoshi S. Sato T. Minamisono J.R. Alonso G.F. Krebs T. J. M. Symons YUAN Da-Qing ZUO Yi FAN Ping T. Suzuki ZHANG Xi-Zhen ZHU Sheng-Yun 《中国物理C(英文版)》2009,33(Z1)
Nuclear structure of proton-rich unstable nucleus 28P has been studied by measuring its g-factor for the first time. The g-factor of 28P (Iπ =3+, T1/2=270.3 ms) was measured by means of β-NMR technique combined with the new polarization technique for charge exchange reaction product in the intermediate energy heavy ion collisions. The obtained g-factor of g=0.1028(27) is very much quenched from the Schmidt value,but is well reproduced by the shell model (+0.102). In connection with the magnetic moment of the mirror partner and the β-ray transition probability, the orbital angular momenta and intrinsic spins of protons and neutrons have been determined as 〈lp〉 = 0.43(29), 〈ln〉 = 1.85(29), 〈Sp〉 = 0.28(4), and 〈Sn〉 = 0.44(4). 相似文献
77.
K. Matsuta M. Izumi A. Kitagawa Y. Nojiri T. Minamisono A. Ozawa T. Ohtsubo S. Momota Y. Matsuo K. Sugimoto K. Omata Y. Shida I. Tanihata S. Shimoura T. Kobayashi J. R. Alonso G. F. Krebs T. J. M. Symons 《Hyperfine Interactions》1990,61(1-4):1387-1390
The lifetime and magnetic moment of43Ti (Iπ-7/2−, T1/2=0.50 sec), one of the mirror beta-radioactive nuclei in the f7/2-shell, have been measured with a fragment separator built at the Bevalac of the LBL. By means of the beta-NMR method on43Ti, a preliminary value of the magnetic moment of43Ti was determined to be μ=(0.70±0.07) μπ. 相似文献
78.
Klay JL Ajitanand NN Alexander JM Anderson MG Best D Brady FP Case T Caskey W Cebra D Chance JL Chung P Cole B Crowe K Das AC Draper JE Gilkes ML Gushue S Heffner M Hirsch AS Hjort EL Huo L Justice M Kaplan M Keane D Kintner JC Krofcheck D Lacey RA Lauret J Law C Lisa MA Liu H Liu YM McGrath R Milosevich Z Odyniec G Olson DL Panitkin SY Pinkenburg C Porile NT Rai G Ritter HG Romero JL Scharenberg R Schroeder L Srivastava B Stone NT Symons TJ Wang S Wells R Whitfield J Wienold T Witt R Wood L 《Physical review letters》2002,88(10):102301
Rapidity distributions of protons from central 197Au+197Au collisions measured by the E895 Collaboration in the energy range from (2-8)A GeV at the Brookhaven AGS are presented. Longitudinal flow parameters derived using a thermal model including collective longitudinal expansion are extracted from these distributions. The results show an approximately linear increase in the longitudinal flow velocity, (L), as a function of the logarithm of beam energy. 相似文献
79.
Martyn C.R. Symons Graham Eaton T Ann Shippey John M. Harvey 《Chemical physics letters》1980,69(2):344-347
Infrared spectra ot acetone in the CO stretching region have been studied as a function of the composition of a range of mixed protic-aprotic solvents. For methanolic systems, equilibria between hydrogen-bonded and non hydrogen-bonded acetone dominate the spectral changes, but for aqueous systems at least four distinct components need to be considered. 相似文献
80.
D. Nishimura J. Komurasaki K. Matsuta M. Mihara R. Matsumiya S. Momota T. Ohtsubo T. Izumikawa H. Hirano A. Kitagawa M. Kanazawa M. Torikoshi S. Sato M. Fukuda D. Ishikawa T. Minamisono R. Watanabe T. Kubo Y. Nojiri J. R. Alonso G. F. Krebs T. J. M. Symons 《Hyperfine Interactions》2007,180(1-3):71-74
The magnetic moment of short lived β-emitter 24mAl (426 keV, I π ?=?1?+?, T 1/2?=?131 ms) has been measured by means of β-NMR technique, for the first time. From the β-NMR spectrum, the magnetic moment was determined as $\left| {\upmu}\left( ^{\rm 24m}{\rm Al} \right) \right|=\left( {2.99\pm 0.09} \right){\upmu}_{\rm N}$ . Combined with the known magnetic moment of the mirror partner 24mNa, the expectation value of <?S z?> is obtained to be (0.08 ± 0.12). These values are reproduced well by the shell model calculation. 相似文献