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61.
A new integral transform arising from a theory of imaging based on Compton scattering is introduced and the explicit expression for its inverse is established. Its properties serve as foundation to a new nuclear emission imaging principle. To cite this article: M.K. Nguyen, T.T. Truong, C. R. Acad. Sci. Paris, Ser. I 335 (2002) 213–217. 相似文献
62.
Truong Bach 《Zeitschrift für Physik A Hadrons and Nuclei》1978,285(1):1-2
In order to use the same wave-functions for comparisons between different Starkbroadening (semi-classical) theories, Thomas-Fermi and Coulomb oscillator-strengths are computed for the All 3p-nd, and 4s-n'p transition arrays. 相似文献
63.
On the existence of efficient points in locally convex spaces 总被引:1,自引:0,他引:1
Truong Xuan Duc Ha 《Journal of Global Optimization》1994,4(3):265-278
We study the existence of efficient points in a locally convex space ordered by a convex cone. New conditions are imposed on the ordering cone such that for a set which is closed and bounded in the usual sense or with respect to the cone, the set of efficient points is nonempty and the domination property holds. 相似文献
64.
The characteristic energy scale for a one-dimensional electron gas is obtained through the scaling equations for the invariant couplings in next leading order divergence renormalization. This characteristic energy is proportional to the gap of the spin density excitations spectrum. 相似文献
65.
We construct the simplest solvable non-trivial (S ≠ 1) supersymmetric model: the supersymmetric Ising field theory. The supersymmetric generalization of the duality order/disorder algebra is discussed. Finally we attempt to “double” the model and comment on the connection between this doubled model and the unsolved problem of the supersymmetric sine-Gordon kink structure. 相似文献
66.
A new type of semi-active hydraulic engine mount using controllable area of inertia track 总被引:1,自引:0,他引:1
Thanh Quoc Truong 《Journal of sound and vibration》2010,329(3):247-4446
Automotive engine mounts function to constrain the engine shake motion resulting at low-frequencies, as well as to isolate noises and vibrations generated by the engine with unbalanced disturbances at the high frequencies. The property of the mount depends on vibration amplitude and excitation frequency. It means that the excitation amplitude is large in low excitation frequency range and small in high frequency range. In this paper, a new hydraulic engine mount with a controllable area of inertia track is proposed and investigated. Theoretical works with the mount model to isolate the engine-related vibrations were conducted by an optimal algorithm to control the area of the inertia track under shocks and multi-signal force excitations. This research clearly gives an analysis of the considerable changes in the mount dynamic properties according to the changes in the inertia track area. Consequently, when the inertia track area is tuned, the transmissibility of the mount is effectively reduced. 相似文献
67.
68.
This paper presents a new design for an insensitive-polarization all-optical switch using 2 × 2 multimode interference (MMI) couplers. The switching structure can operate at central operating wavelength 1550 nm for both polarizations. A nonlinear directional coupler is used to realize the phase shifter and therefore switching mechanism is obtained. The transfer matrix method and beam propagation method are used to design and optimize the whole device structure. 相似文献
69.
Thi Lieu Nguyen Van Hoang Cao Thi Hai Yen Pham Truong Giang Le 《Electroanalysis》2019,31(12):2538-2545
Platinum nanoflowers modified glassy carbon electrodes (PtNFs/GCE) was fabricated simply for lead determination in water samples. The modified electrodes were prepared by electrodeposition in hexachloroplatinic acid solution at constant potential. The influence of deposition time and potential on surface morphology, chemical composition, electrochemical properties of electrode were investigated. At ?0.2 V of potential and 150 s of deposition duration, platinum developed as nanoflower shape and scattered densely all over the glassy carbon surface, producing the largest electrochemically active surface areas. The highest differential pulse stripping voltammetry (DPSV) signal of lead was obtained by using the prepared electrode. Under optimized experimental condition of electrolyte, accumulation potential and time, the peak current was found to be linear proportion to lead concentration in range of 1 to 100 μg L?1 (slope=0.371) with a limit of detection of 0.398 μg L?1. The method has good repeatability and reproducibility with relative standard deviations of 1.47 % and 4.83 %, respectively. The modified PtNFs/GCE also demonstrated an excellent long‐term stability with only 9 % decrease in Pb peak current over 30 days. Moreover, the performance of the modified PtNFs/GCE in determination of Pb(II) in two industrial wastewaters was good agreement with data obtained by a graphite furnace atomic absorption spectrometry (GFAAS) method. 相似文献
70.
Hassan Osseili Khai‐Nghi Truong Thomas P. Spaniol Laurent Maron Ulli Englert Jun Okuda 《Angewandte Chemie (International ed. in English)》2019,58(6):1833-1837
Facile α‐H elimination from tetrakis(trimethylsilylmethyl)titanium precursors to give adducts of (alkylidene)bis(alkyl)titanium complexes is induced by light alkali metal amides of the NNNN‐type macrocyclic anionic ligand Me3TACD [(Me3TACD)H=1,4,7‐trimethyl‐1,4,7,10‐tetraazacyclododecane]. In the crystal, the alkali metal interacts with the carbene carbon atom or with the CH2 group of the trimethylsilymethyl ligand. The nucleophilic character of the carbene carbon atom was shown by the reaction with benzophenone and terminal acetylenes. 相似文献