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991.
992.
T. G. Kuznetsova K. G. Ione N. F. Salakhutdinov 《Reaction Kinetics and Catalysis Letters》1997,62(2):273-280
The interaction of α-methacrolein with mixedtrans- andcis-alloocimenes on β zeolite has been studied at room temperature in a solvent under various conditions. The scheme of the process
has been specified including the formation of (4+2) and (3+2)-cycloaddition products and strongly adsorbed alloocimene species. 相似文献
993.
Quenching of fluorescence from Na(32
P) and K(42
P) atoms by various collision partners was studied at 973 and 1273K. Excited alkali atoms were produced photolytically by excimer
laser light at 193nm. For each collision pair, the appropriate relative velocity was computed and used to evaluate the quenching
cross-section from the measured rate constants. Cross sections for CO2, O2 and N2 are large (10–60Å2) while for Ar, the values are <1 Å2. The results are compared with those of previous investigations as a function of relative velocity. Finally, implications
for combustion diagnostics are briefly discussed.
Received: 29 March 1996 相似文献
994.
Takafumi Adachi Ichimin Shirotani Junichi Hayashi Osamu Shimomura 《Physics letters. A》1998,250(4-6):389-393
Lanthanide monophosphides LnP (Ln = La, Ce, Pr, Nd, Sm, Gd, Tb, Tm and Yb) with a NaCl-type structure have systematically been prepared at high temperatures. Using synchrotron radiation, X-ray diffractions of LnP have been studied up to 61 GPa at room temperature. The NaCl---CsCl transition for CeP is found at around 25 GPa. First-order phase transitions of LnP (Ln = La, Pr and Nd) with the crystallographic change occur at around 24, 26 and 30 GPa, respectively. The structure of the high pressure phases of these phosphides is a body center tetragonal structure (Ln: 0, 0, 0; P: 1/2, 1/2, 1/2; space group P4/mmm), which can be seen as the distorted CsCl-type structure. The Pr---P distance in the high pressure form of PrP is 2.789 Å. This almost agrees with the sum of covalent radii of Pr and P. The Pr---P bond has the covalent character at very high pressures. Similar results are also obtained for LaP and NdP. The pressure-induced phase transitions of SmP, GdP, TbP, TmP and YbP occur at around 35, 40, 38, 53 and 51 GPa, respectively. The structure of the high pressure phase is unknown. The phase transitions of LnP with many f-electrons are not due to the mechanism of the ordinary NaCl---CsCl transition. The transition pressures of LnP increase with decreasing the lattice constants in the NaCl-type structure, which decrease with increasing atomic number of the lanthanide atoms. 相似文献
995.
We propose a new method for computing multimode wave interactions in towing systems; our method is based on wave splitting
of the equations of a model in such a way that each computational step requires computation for only one mode. The efficiency
of the method is demonstrated by analysis of a concrete towing system with a turning towboat.
Translated fromDinamicheskic Sistermy. Vol. 12, pp. 55–64, 1993. 相似文献
996.
Zólomy A. Berceli T. Járó G. Hilt A. Marozsák T. 《Optical and Quantum Electronics》1998,30(11-12):969-983
Optical and Quantum Electronics - A new approach for the design and construction of low noise broadband optical receivers is presented utilizing distributed amplification based on hybrid integrated... 相似文献
997.
A. T. Barabanov 《Journal of Mathematical Sciences》1998,90(6):2537-2540
We propose criteria for controllability and observability of stationary systems specified by complex domain models. Conclusions
concerning controllability and observability are made on the basis of coefficients in the corresponding transfer functions.
Translated fromDinamicheskie Sistemy, Vol. 12, pp. 120–126, 1993. 相似文献
998.
T Kloks D Kratsch C.K Wong 《Journal of Algorithms in Cognition, Informatics and Logic》1998,28(2):272-289
We present two algorithms solving the minimum fill-in problem on circle graphs and on circular-arc graphs in timeO(n3). 相似文献
999.
A.M. El-Badry T. Kuroyanagi S. Mitarai A. Odahara Y. Gono S. Morinobu K. Ogawa 《The European Physical Journal A - Hadrons and Nuclei》1998,3(2):133-138
A recoil distance method was used to measure half-lives of the excited states of 145Sm. The reaction used was 139La(10B, 4n)145Sm. A plunger system was used. Half-lives were determined for two excited states for the first time. The yrast 27/2+ state was found to have a half-life of 1.1 ± 0.2 ns corresponding to the retardation of 3.1 × 10−4 comparing with the single particle estimate of M1. The excitation energy of this state was well reproduced by the shell model
calculation having a mixed configuration of [π{h11/2(g7/2)−2 (d5/2)−1}10−, νf7/2] + [π{h11/2(g7/2)−1}9−,νh9/2]. Another retarded E1 transition was also found in a decay of a 21/2+ state. Its retardation was 1.6 × 10−4 comparing with the single particle value.
Received: 9 September 1997 / Revised version: 12 June 1998 相似文献
1000.
Studies of the influence of plastic deformation and the straining temperature on the temperature dependence of the stresses
developed in titanium nickelide shape memory alloys are described.
Zh. Tekh. Fiz. 68, 141–142 (July 1998) 相似文献