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131.
132.
The 75As(d, p)76As reaction was investigated with 11 MeV deuterons. Thirty levels of the residual nucleus were identified up to about 1.8 MeV excitation energy, and angular distributions were measured. Spectroscopic factors and ln values were obtained for low-lying transitions by means of a distorted-wave analysis of the differential cross sections. The ln = 4 transition to the ground state of 76As and the presence of ln = 2 transitions to low-lying levels provide a strong support to the assumption that nuclei in this mass region have a large deformation parameter. The results are compared with the 75As(n, γ)76As data. 相似文献
133.
Mordechai Lewin 《Discrete Mathematics》1975,11(2):187-189
It is shown that a collection of circular permutations of length three on an n-set generates the alternating group An if and only if the associated graph is connected. It follows that [] circular permutations of length three may generateAn. 相似文献
134.
Mordechai Lewin 《Journal of Combinatorial Theory, Series B》1978,25(3):245-257
Given n and i, n > 2, 2 ≤ i ≤ n ? 1, the smallest size of an n-graph without endvertices is obtained, which ensures a path of length i between any two vertices of the graph. 相似文献
135.
Mevorat-Kaplan K Brumfeld V Engelhard M Sheves M 《Photochemistry and photobiology》2006,82(6):1414-1421
Halorhodopsin from Natronobacterium pharaonis (pHR) is a light-driven chloride pump in which photoisomerzation of a retinal chromophore triggers a photocycle which leads to a chloride anion transport across the plasma membrane. Similarly to other retinal proteins the protonated Schiff base (PSB), which covalently links the retinal to the protein, does not experience hydrolysis reaction at room temperature even though several water molecules are located in the protonated Schiff base (PSB) vicinity. In the present studies we have revealed that in contrast to other studied archaeal rhodopsins, temperature increase to about 70 degrees C hydrolyses the PSB linkage of pHR. The rate of the reaction is affected by Cl-concentration and reveals an anion binding site (in addition to the Cl- in the SB vicinity) with a binding constant of 100mM (measured at 70 degrees C). We suggest that this binding site is located on the extracellular side and its possible role in the Cl-pumping mechanism is discussed. The rate of the hydrolysis reaction is affected by the nature of the anion bound to pHR. Substitution of the Cl- anion by Br-, I- and SCN- exhibits similar behavior to that of CI- in the region of 100mM but higher concentrations are needed for N3-, HCOO- and NO2-to achieve similar behavior. Steady state pigment illumination accelerates the reaction and reduces the energy of activation and the frequency factor. Adjusting the sample temperature to 25 degrees C following the hydrolysis reaction led to about 80% pigment recovery. However, the newly reformed pigment is different from the mother pigment and has different characteristics. It is concluded that the apo-membrane adopts a modified conformation and/or aggregated state which rebinds the retinal to give a new conformation of the pHR pigment. 相似文献
136.
Rachel Ta-Shma Mordechai Chevion Abed Al Aziz Quntar Morris Srebnik 《Tetrahedron》2006,62(23):5469-5473
Three pyrimidine derivatives (8a-c), differing from isouramil and divicine at C2, have been synthesized and their autoxidation rates measured spectrophotometrically. The autoxidation rates of all five pyrimidines (8a-c, isouramil and divicine) were correlated with values (rho=−1.28, r2=0.949). 相似文献
137.
138.
We study, theoretically and experimentally, the nonlinear dynamics of a wave packet launched inside a trap potential. Increasing the power of the wave packet transforms its dynamics from linear tunneling through a potential barrier, to soliton tunneling, and eventually, above a well-defined threshold, to the ejection of a soliton from the potential trap. 相似文献
139.
We provide a negative answer to an old question in tight closure theory by showing that the containment in holds for infinitely many but not for almost all prime characteristics of the field . This proves that tight closure exhibits a strong dependence on the arithmetic of the prime characteristic. The ideal has then the property that the cohomological dimension fluctuates arithmetically between 0 and .
140.
Fleischer JW Bartal G Cohen O Manela O Segev M Hudock J Christodoulides DN 《Physical review letters》2004,92(12):123904
We present the experimental observation of both on-site and off-site vortex-ring solitons of unity topological charge in a nonlinear photonic lattice, along with a theoretical study of their propagation dynamics and stability. 相似文献