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1.
We carried out detailed calculations for photorefractive wave-mixing switches based on one of three crystals with high electro-optic coefficients, namely, BaTiO3, Strontium Barium Niobate (SBN (0.75)), and Potasium Sodium Strontium Barium Niobate (KNSBN). A comparison of results for the three crystals shows that a 0_-cut BaTiO3 crystal is suitable for a longitudinal switch and requires a voltage of about 80 for a 2-mm-thick crystal to induce sufficient phase mismatch. The electrodes must be transparent for the incident and diffracted beams. A 45_-cut SBN (0.75) crystal, however, is suitable for a lateral switch and requires a voltage of about 150 for a 1-mm-wide crystal. The electrodes do not need to be transparent.  相似文献   
2.
Dehydration of zinc biladienone was catalyzed by zinc acetate, while the reverse reaction was catalyzed by triethylamine. The transformation can be performed thermally without catalyst, and the ratio of the hydrated form to the dehydrated form depended on the solvents: the dehydrated form is favored in CHCl3 and CH2Cl2, while the hydrated form is favored in hexane, pyridine, and DMF. Kinetic studies on the thermal transformation of zinc biladienone from its hydrated blue form to the dehydrated yellow-brown form were performed in toluene and THF. The rate law was half order with respect to the zinc biladienone concentration in toluene, while first order in THF, leading to a slow transformation in concentrated solution in toluene.  相似文献   
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4.
A series of panchromatic ruthenium sensitizers ( MJ sensitizers) with attached thiophene and phenyl units bearing alkyl chains was synthesized. A new synthetic route was used to examine all possible positions for the alkyl chains. The absorption spectra showed the sum of a ruthenium complex and peripheral organic chromophore units. The hypochromic effect and blueshift of the metal‐to‐ligand charge‐transfer band observed in the modified ruthenium sensitizers were suppressed by changing the positions of the alkyl chains on the attached thiophene ring. Changing only one alkyl chain also influenced the performance of dye‐sensitized solar cells. Ruthenium sensitizer MJ‐10 with bulky substituent harvests visible and near‐infrared light, and solar cells sensitized by MJ‐10 exhibit an efficiency of 9.1 % under 1 sun irradiation.  相似文献   
5.
Cellulose - High hygroscopicity is an unavoidable feature of cellulose materials, and it is important for clarifying the humidity dependence of the target function toward precise utilization....  相似文献   
6.
The rotational spectrum of methyl formate (HCOOCH3) has been observed in the frequency range from 7 to 200 GHz. We newly assigned 1612 lines in the ground torsional state and simultaneously analyzed both A- and E-species data including previously reported lines on the basis of the internal axis method. A total of 3077 lines were fitted to a 1σ standard deviation of 139 kHz, and molecular parameters were determined.  相似文献   
7.
Kierstead showed that every computable marriage problem has a computable matching under the assumption of computable expanding Hall condition and computable local finiteness for boys and girls. The strength of the marriage theorem reaches or if computable expanding Hall condition or computable local finiteness for girls is weakened. In contrast, the provability of the marriage theorem is maintained in even if local finiteness for boys is completely removed. Using these conditions, we classify the strength of variants of marriage theorems in the context of reverse mathematics. Furthermore, we introduce another condition that also makes the marriage theorem provable in , and investigate the sequential and Weihrauch strength of marriage theorems under that condition.  相似文献   
8.
The extraction and separation of lanthanides have been investigated using CHON-type extractants, which are composed of only C, H, O, and N atoms. N,N-Dioctyldiglycol amic acid (DODGAA) showed high extraction and separation performances for heavier lanthanides compared with typical CHON-type extractants. On the other hand, N,N,N',N'-tetrakis(2-pyridylmethyl)ethylenediamine (TPEN) provided an unprecedentedly high selectivity for lighter lanthanides. Furthermore, it was found that the combination of DODGAA and TPEN under suitable conditions enabled the mutual separation of light, middle, and heavy lanthanides.  相似文献   
9.
By the method of microwave cavity resonance the authors have measured the temporal variation of the lctron density following the laser excitation of neon glow-discharge plasma, and the result is compared with the optogalvanic signal. It is found that the optogalvanic signal does not represent the change in the electron density; i.e., the time resolution is poor and the absolute magnitude is smaller by an order.  相似文献   
10.
Infrared microwave double resonance signals have been observed for CH3OH using the 3.5-μm HeXe laser line. When microwave transitions in the ground vibrational state are pumped, the double resonance signals are obtained on two infrared transitions v = 1 ← 0 of νCH(a′); v = 1, J, K, μ = 4, 2, 1 ← v = 0, J, K, μ = 3, 2, 1, and 4, 3, 1 ← 3, 3, 1. Three weak double resonance signals are due to the collision-induced transitions. Their relative intensities have been explained successfully by using the rate constants of collision-induced transitions which are proportional to the dipole matrix elements between the states involved in the transitions.  相似文献   
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