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941.
Yuto Suzuki Mario Gutirrez Senri Tanaka Eduardo Gomez Norimitsu Tohnai Nobuhiro Yasuda Nobuyuki Matubayasi Abderrazzak Douhal Ichiro Hisaki 《Chemical science》2021,12(28):9607
The library of isostructural porous frameworks enables a systematic survey to optimize the structure and functionality of porous materials. In contrary to metal–organic frameworks (MOFs) and covalent organic frameworks (COFs), a handful of isostructural frameworks have been reported for hydrogen-bonded organic frameworks (HOFs) due to the weakness of the bonds. Herein, we provide a rule-of-thumb to develop isostructural HOFs, where we demonstrate the construction of the third and fourth generation of isostructural HAT-based HOFs (TolHAT-1 and ThiaHAT-1) by considering three important structural factors, that are (1) directional H-bonding, (2) shape-fitted docking of the HAT core, and (3) modulation of peripheral moieties. Their structural and photo-physical properties including HCl vapor detection are presented. Moreover, TolHAT-1, ThiaHAT-1, and other isostructural HOFs (CPHAT-1 and CBPHAT-1) were thoroughly compared from the viewpoints of structures and properties. Importantly, molecular dynamics (MD) simulation proves to be rationally capable of evaluating the stability of isostructural HOFs. These results can accelerate the development of various isostructural molecular porous materials.The library of isostructural porous frameworks enables a systematic survey to optimize the structure and functionality of porous materials. 相似文献
942.
Hirofumi Matsuhata Hirotaka Yamaguchi Tamotsu Yamashita Toshiaki Tanaka Bin Chen Takashi Sekiguchi 《哲学杂志》2013,93(15):1674-1685
Shockley partial dislocations in 4H-SiC were observed using monochromatic synchrotron X-ray topography with a grazing-incidence Bragg-case geometry, that is, Berg–Barrett topography. The contrast of partial dislocations at the edges of Shockley-type stacking faults is discussed in terms of whether they have C- or Si-core edge components, or screw components. The dissociated state of basal-plane dislocation is discussed on a basis of the stacking sequence for basal-planes in the 4H-SiC crystal structure. It is expected that the results obtained in this study will be useful for characterizing Shockley-type stacking faults in Berg–Barrett topography. 相似文献
943.
M. Tanaka H. Kohri T. Ohta M. Yosoi M. Fujiwara K. Ueda S. Imoto K. Takamatsu J. -P. Didélez G. Frossati A. de Waard Yu. Kiselev S. Makino H. Fujimura K. Fukushima S. Fukushima H. Kondoh 《Physics of Particles and Nuclei》2013,44(6):959-963
The project in producing the hyperpolarized 3He and 19F are addressed in pursuit of radiation free medical diagnosis. The program for production of the hyperpolarized 3He by the brute force method with the Pomeranchuk cooling and the rapid melting of the solid 3He started a few years ago, and is still on the way, while a new program for production of the hyperpolarized 19F by means of the PHIP (ParaHydrogen Induced Polarization) has just got started. Particular attention is placed upon a new idea of the hyperpolarization catalyst to be used for 19F. 相似文献
944.
Haruyuki Inui Norihiko L. Okamoto Takashi Hashimoto Katsushi Tanaka Masaharu Yamaguchi 《哲学杂志》2013,93(12):1463-1478
The defect structures in orthorhombic C54 crystallites in thin films of Mo-doped TiSi 2 produced by co-sputtering have been investigated by transmission electron microscopy. Almost all C54 crystallites contain a twin boundary parallel to (101), dividing a crystallite into two regions, each of which also contains many thin twins with the habit plane parallel to (001), which is inclined by about 45° from (101). Both of the two regions divided by the twin boundary parallel to (101) tend to have facets on (001) as well as thin twins with the habit plane parallel to (001). As a result, C54 crystallites exhibit a characteristic shape just like an oak leaf. While twins with the (001) habit plane have been observed in C54 crystallites in both binary and Mo-doped TiSi 2 thin films, those with the (101) habit plane are present only in Mo-doped TiSi 2 thin films. The twinning elements for (101) twins are determined to be K 1 = (101), , K 2 = (001) and m2 = [100]. The origin of (101) twins in Mo-doped TiSi 2 is discussed in terms of the change in the c / a axial ratio upon alloying TiSi 2 with Mo. 相似文献
945.
H. Horima T. Yamanishi S. Tanaka H. Kumamaru T. Nakahara K. Ishihara 《Fiber and Integrated Optics》2013,32(2-3):149-163
Abstract Jelly-filled optical fiber cables have been investigated. The waterproof characteristics and transmission and mechanical properties of the fabricated jelly-filled cables, including temperature and aging characteristics, were sufficient to apply them for practical use. 相似文献
946.
A micro liquid chromatograph-interfaced Fourier transform infrared spectrophotometer system (LC/FTIR) for on line analysis of liquid chromatography effluents is described. About 2 μg of injected diethylphthalate can be detected using a 0.025 mm pathlength flow cell. Several examples of a micro LC/FTIR are demonstrated. 相似文献
947.
K. Miki A. Tamii N. Aoi T. Fukui T. Hashimoto K. Hatanaka T. Ito T. Kawabata H. Matsubara K. Ogata H. J. Ong H. Sakaguchi S. Sakaguchi T. Suzuki J. Tanaka I. Tanihata T. Uesaka T. Yamamoto 《Few-Body Systems》2013,54(7-10):1353-1356
Tensor correlations in 4He were studied via the (p, dp) reaction at the incident energy of 392 MeV with a focus on spin configurations of correlated pn pairs in 4He at high relative momenta ${(P_{\rm rel}^{\rm cor})}$ . The preliminary results show that the correlated pn pair at ${P_{\rm rel}^{\rm cor} = 310 {\rm MeV/c}}$ predominantly has the channel spin S = 1, which is consistent with the characteristics of tensor correlations. 相似文献
948.
Raman scattering intensities of the NO2 symmetric stretching vibration band were measured for some aromatic nitrocompounds. It was shown that in the case of ortho alkyl-substituted nitrobenzenes, the intensities decrease in an orderly fashion with the increase of the degrees of twisting of NO2 group from the plane of benzene ring. From this result, it was assumed that the factor determining the intensities in question is the conjugation effect between NO2 group and benzene ring. Then, the intensities for some para substituted nitrobenzenes were examined, and the influence of substituents was discussed in terms of the conjugation effect. It was shown that when the electron donating character of substituents becomes stronger, the intensities intensity change among the compounds. The more experimental data and the detailed theoretical analysis of them are necessary not only for the elucidation of spectroscopic aspects of the intensity in question, but also for establishing the criterion for the application of it to the group type analysis and the microanalysis. Therefore, further experimental and theoretical examinations are required and now proceeding in our laboratory. 相似文献
949.
The Raman scattering intensities of the NO2 symmetric stretching vibration band were investigated experimentally for some para and meta substituted nitrobenzenes. The excitation profiles obtained with the six excitation wavelengths from 457.9 to 514.5 nm were presented. The results were examined in terms of the Albrecht-Hutley's theory, and the electronic states involved in the preresonance Raman intensity enhancement were suggested. 相似文献
950.
S. Iwai S. Tanaka K. Fujinuma H. Kishida H. Okamoto Y. Tokura 《Phase Transitions》2013,86(7-8):807-813
Initial dynamics of photo-induced ionic (I) to neutral (N) phase transition in tetrathiafulvalene- p -chloranil (TTF-CA) was investigated by femtosecond reflection spectroscopy with various excitation intensities. A charge transfer excitation in the I phase produces N donor (D 0 )-acceptor (A 0 ) strings within 2 ps. For a weak excitation intensity, these initial N states decay with a life time of 300 ps at 4 K, but rather multiply leading to macroscopic I-N conversion within 20 ps at 77 K just below the N-I transition temperature T NI . Near T NI , we also found the coherent motion of the macroscopic N-I domain boundary with a period of 85 ps. 相似文献