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21.
Sunanda Banerjee Rohini M Godbole Sreerup Raychaudhuri Ben Allanach Sunanda Banerjee Satyaki Bhattacharyya Debajyoti Choudhury Siba Prasad Das Anindya Datta Rohini M Godbole Monoranjan Guchait Sabine Kraml Gobinda Majumdar David Miller Margarete Mühlleitner Nobuchika Okada Maxim Perelstein Santosh K Rai Sreerup Raychaudhuri Saurabh D Rindani DP Roy K Sridhar Rishikesh Vaidya D Zeppenfeld 《Pramana》2006,67(4):617-637
This is summary of the activities of the working group on collider physics in the IXth Workshop on High Energy Physics Phenomenology
(WHEPP-9) held at the Institute of Physics, Bhubaneswar, India in January 2006. Some of the work subsequently done on these
problems by the subgroups formed during the workshop is included in this report. 相似文献
22.
We have characterized multidielectric scaled SONOS nonvolatile memory structures with the quasi-static linear voltage ramp (LVR) technique and dynamic pulse measurements. We have formulated physically-based ERASE/WRITE and retention methods with deep level amphoteric traps which capture and emit carriers to the bands in the silicon nitride film. Amphoteric trap parameters are extracted by the LVR technique. ERASE/WRITE and retention amphoteric trap model simulations agree well with the experimental dynamic pulse measurements. Experimental scaled SONOS structures have been fabricated with tunnel oxide XOT=20 Å, nitride XN=30 Å and blocking oxide XOB=55 Å and demonstrated a static flatband shift of 3.6 V with ±5 V programming voltages. These structures may be used as the nonvolatile memory element in high density VLSI circuits. 相似文献
23.
The stannous chloride dihydrate-mediated deprotection-bicyclisation of a range of amides possessing a pendant acetal group is reported. These mild reaction conditions have been used to prepare a number of ring-fused heterocyclic compounds, some in enantiomerically pure form, which should be of interest both in their own right and as building blocks for the production of more complex target molecules. 相似文献
24.
O.G. Kosareva N.A. Panov N. Akozbek V.P. Kandidov Q. Luo S.A. Hosseini W. Liu J.-F. Gravel G. Roy S.L. Chin 《Applied physics. B, Lasers and optics》2006,82(1):111-122
We demonstrate a three orders of magnitude increase and stability in the backscattered fluorescence signal from nitrogen molecules
by terawatt femtosecond laser pulse induced air filaments using a new method. The method is based on squeezing the initial
beam diameter using a telescope. The effect of laser shot-to-shot fluctuations was included in numerical simulations by a
random distribution of the initial intensity in both squeezed and non-squeezed beams. Statistical processing of the simulation
results shows that the average diameter of plasma channels as well as the total amount of free electrons generated in a bunch
of multiple filaments in air is larger in the squeezed beam. Shot-to-shot stability of the simulated plasma density increases
in the squeezed beam. The change of this plasma density with propagation distance is in good qualitative agreement with the
change of the range-corrected nitrogen fluorescence signal with distance.
PACS 42.65.Jx; 42.60.Jf; 42.68.Ay; 42.68.Wt 相似文献
25.
A. M. Yakunin A. Yu. Silov P. M. Koenraad W. Van Roy J. De Boeck J. H. Wolter 《Superlattices and Microstructures》2003,34(3-6):539
An individual Mn acceptor in GaAs is mapped by cross-sectional scanning tunneling microscopy (X-STM) at room temperature and a strongly anisotropic shape of the acceptor state is observed. An acceptor state manifests itself as a cross-like feature which we attribute to a valence hole weakly bound to the Mn ion forming the (Mn2+3d5+hole) complex. We propose that the observed anisotropy of the Mn acceptor wavefunction is due to the d-wave present in the acceptor ground state. 相似文献
26.
M. C. Caracoche J. A. Martínez P. C. Rivas M. A. Taylor A. F. Pasquevich S. Barolin O. A. de Sanctis 《Hyperfine Interactions》2007,179(1-3):87-93
The hyperfine quadrupole interaction at Hf sites in films and powders of 14 mol% CaO–HfO2 and 20 mol% CaO–HfO2 has been determined as a function of temperature. Results indicate the formation of a cubic solid solution and other microstructures assigned to the ?1 (CaHf4O9) and ?2 (Ca6Hf19O44) phases. Dynamical effects on the electric field gradient reveal the existence of oxygen vacancies movements in the solid solution. The thermal behavior of the relaxation constant observed in films allowed the determination of activation energies of 0.54 eV and 0.70 eV for the 14 mol% and 20 mol% CaO doped hafnias, respectively. The influence of the microdomains and the stability of the cubic solid solution are discussed. 相似文献
27.
28.
We demonstrate the phenomenon of Talbot self-image plane shift by tuning the wavelength of the broadband light source. A superluminescent diode (SLD) is used as a broad-band light source and an acousto-optic tunable filter (AOTF) as wavelength-scanning device. A periodic grating is illuminated by the wavelength tuned light of SLD using AOTF and Talbot self-image plane is shifted continuously in the longitudinal direction without mechanically moving the grating. The wavelength-scanning Talbot effect is then implemented for the measurement of arbitrary step-height of discontinuous objects with extended range. The main advantages of the proposed system are non-mechanical scanning, high stability because of it’s common-path geometry and compactness. Since the measurement of the phase is not required the system is free from phase ambiguity problem and therefore, the range of measurement is large as compare to interferometric techniques. 相似文献
29.
30.
Jean E. Taylor 《Discrete and Computational Geometry》1991,6(1):225-262
We bound the number of plane segments in a crystalline minimal surface S in terms of its Euler characteristic, the number
of line segments in its boundary, and a factor determined by the Wulff shapeW of its surface energy function. A major technique in the proofs is to quantize the Gauss map ofS based on the Gauss map ofW. One thereby bounds the number of positive-curvature corners and the interior complexity ofS.
The support of the National Science Foundation and the Air Force Office of Scientific Research and the hospitality of Stanford
University, where this paper was extensively rewritten, are gratefully acknowledged. 相似文献