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51.
A new technique for two-dimensional smoothing is proposed to generate smooth laser irradiation profiles on laser fusion targets employing the broad bandwidth of KrF lasers. In this technique, a wedged etalon is used to get angular dispersion to the orthogonal direction to the one-dimensional broadband random-phase smoothing effect. The preliminary experiment has demonstrated its effectiveness.  相似文献   
52.
Dynamic mechanical properties of cold-compacted films of polyethylene prepared by γ-ray-induced polymerization in bulk at 30°C are discussed in connection with the fine structure. The cold-compacted films show a broad α-relaxation at a lower temperature than do single-crystal mats or melt-crystallized polymer. From the effects of annealing and swelling by carbon tetrachloride on the relaxation, it is concluded that the α-relaxation, like the α-relaxation in the single-crystal mats, originates from molecular motions within lamellar crystals. This is consistent with the finding that these films are composed of stacked small irregular lamellar crystals. The γ-relaxation is also similar to that in crystal mats.  相似文献   
53.
We study the influence of external multiplicative noise on the electrohydrodynamic instability (EHD) in nematic liquid crystals. It turns out that the correlation time n and the intensityQ of the noise are the crucial parameters to control the system. Different types of noise lead to minor quantitative changes when compared to Gaussian white noise, leaving the qualitative aspects unchanged. With increasing noise intensity the threshold for the onset of the first instability changes drastically. We observe that the curvature arising when the threshold of the various instabilities is plotted as a function of the noise intensity changes as one is going, e.g., from the onset of Williams domains (WD) to the onset of the grid pattern (GP). This result reflects the transition in the flow structure from two-dimensional (WD) to three-dimensional (GP, DSM) flow patterns. As the intensity of the noise is increased further, the onset of the first instability becomes more complex. The measurement of the nonlinear onset time shows a strong dependence on the noise intensityQ, which is linear for WD and GP well above onset. The linear onset time shows an unexpected dependence on the noise intensity close to the onset of the first instability. For sufficiently long correlation times of the noise, a destabilization by noise is obtained.  相似文献   
54.
In the previous paper [9] the author proved the joint limit theorem for the Riemann zeta function and the Hurwitz zeta function attached with a transcendental real number. As a corollary, the author obtained the joint functional independence for these two zeta functions. In this paper, we study the joint value distribution for the Riemann zeta function and the Hurwitz zeta function attached with an algebraic irrational number. Especially we establish the weak joint functional independence for these two zeta functions. Received: 17 Apri1 2007  相似文献   
55.
We designed and synthesized a photocontrollable peroxynitrite (ONOO(-)) generator, P-NAP, which has N-methyl-N-nitrosoaminophenol structure with four methyl groups introduced onto the benzene ring to block reaction of the photodecomposition product with ONOO(-) and to lower the semiquinoneimine's redox potential. The semiquinoneimine intermediate generated by photoinduced release of nitric oxide (NO) reduces dissolved molecular oxygen to generate superoxide radical anion (O(2)(?-)), which reacts with NO to afford ONOO(-) under diffusion control (k = 6.7 × 10(9) M(-1) s(-1)). NO release from P-NAP under UV-A (330-380 nm) irradiation was confirmed by ESR spin trapping. Tyrosine nitration, characteristic of ONOO(-), was demonstrated by HPLC analysis of a photoirradiated aqueous solution of P-NAP and N-acetyl-l-tyrosine ethyl ester. ONOO(-) formation was confirmed with a ONOO(-)-specific fluorogenic probe, HKGreen-3, and compared with that from 3-(4-morpholinyl)sydnonimine hydrochloride (SIN-1), which is the most widely used ONOO(-) generator at present. The photoreaction of P-NAP was influenced by superoxide dismutase, indicating that generation of O(2)(?-) occurs before ONOO(-) formation. The quantum yield for formation of duroquinone, the main P-NAP photodecomposition product, was measured as 0.86 ± 0.07 at 334 nm with a potassium ferrioxalate actinometer. Generation of ONOO(-) from P-NAP in HCT-116 cells upon photoirradiation was successfully imaged with HKGreen-3A. This is the first example of a photocontrollable ONOO(-) donor applicable to cultured cells.  相似文献   
56.
Nitroxyl (HNO), a one-electron-reduced form of nitric oxide, has various biological activities, including a cardioprotective effect. Here, we first synthesized another, more hydrophilic photocontrollable HNO donor (3), which can release HNO in a spatially and temporally controlled manner, and then examined the properties of our series of compounds as practical HNO donors in a cellular system under photocontrol. We selected compound 2 as the preferred donor, and used it to show that calcitonin gene-related peptide (CGRP) can be upregulated in A549 cells via photocontrolled HNO release. This result demonstrates the suitability of this photocontrollable HNO donor for biological investigations.  相似文献   
57.
In this paper we establish the joint universality theorems for pairs consisting of the Riemann zeta function, automorphic \(L\) -functions associated with holomorphic Hecke eigen cusp forms, Rankin–Selberg \(L\) -functions, and symmetric square \(L\) -functions.  相似文献   
58.
In the unidimensional unfolding model, given m objects in general position on the real line, there arise 1 + m(m − 1)/2 rankings. The set of rankings is called the ranking pattern of the m given objects. Change of the position of these m objects results in change of the ranking pattern. In this paper we use arrangement theory to determine the number of ranking patterns theoretically for all m and numerically for m ≤ 8. We also consider the probability of the occurrence of each ranking pattern when the objects are randomly chosen. Received March 5, 2005  相似文献   
59.
The structure of the Diels-Alder cycloadduct formed from 2-(1,2,3-1H-benzotriazol-1-yl)-2-(p-tolyl)-2H-isoindole and dimethyl acetylenedicarboxylate was proved as 11-aza-1-(1,2,3-1H-benzotriazol-1-yl)-11-(4-methylphenyl)-tricyclo-[5.2.1.0(2.7)]undeca-2,4,6.9-tetraene-9,10-dioic acid dimethyl ester. The benzotriazole moiety was located as its 1-yl form, analogous to previous reports. The benzotriazole and the benzene (of tricyclo framework) planes were twisted with an angle of 115.83 degrees. Intramolecular close contacts between benzotriazole and ester are characteristic [N(3)...C(26), 2.754(3)A; N(3)...H(22), 3.26(4)A]. The shortest contact of N(3)...H(22) accounting for the rotation of the methyl group is estimated to be 3.10 A, which might be reasonable as C-H...N-type hydrogen bonding.  相似文献   
60.
A Staphylococcus aureus transpeptidase, sortase A (SrtA), catalyzes selective peptide/protein ligations that have been applied to cell imaging and protein engineering, while the ligations do not proceed to completion due to their reversibility. We successfully enhanced SrtA-mediated protein ligation through the formation of a β-hairpin around the ligation site.  相似文献   
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