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1.
用过氧聚钨酸(PPTA)水溶液,通过离心涂膜法在显微镜载玻片上制备了具有光滑表面且厚度为100nm的PPTA薄膜,利用PPTA薄膜在紫外光照下可研制光栅以及其它光学元件的薄膜材料,具有很高的利用价值。 相似文献
2.
Tomomi Ikemoto Tatsuya Ito Atsuko Nishiguchi Kiminori Tomimatsu 《Tetrahedron》2004,60(48):10851-10857
The efficient synthesis of 2,3-dihydro-1-benzothiepine derivatives 4 has been developed. The intramolecular Claisen type reaction of the new products, 4-(o-formylphenylthio)butyrate 9, with alcoholate in dialkylcarbonate as a solvent afforded 4 in good yields. According to this new procedure, we have accomplished the practical preparation of CCR5 antagonist 1 as a candidate for oral HIV-1 therapy. 相似文献
3.
Akiko Sekihara Hidekazu Honma Tadahiro Fukuju Kiminori Maeda Hisao Murai 《Research on Chemical Intermediates》1998,24(8):859-877
Photooxidation (charge transfer) reactions of carbazole derivatives by maleic anhydride (MA) in alcoholic media are studied
by a time-resolved cw-ESR (TRESR) and Fourier transform ESR (FTESR) techniques. The CIDEP spectra observed in the systems
(methyl-, ethyl-, and phenyl-substituted carbazoles with MA) remarkably depend on the MA concentration. Under the high concentration
conditions, an emissive TM (triplet mechanism) polarization with a slight A/E (absorption/emission) pattern of the RPM (radical
pair mechanism) is observed. In the low concentration of MA, a TM-like absorptive polarization is superimposed on the A/E
pattern of the RPM. Since this reaction takes place exclusively through the triplet state, this spectral phase reveals that
the singlet state of the radical-ion pair (RIP) has an energy higher than that of the triplet state, in other words, the sign
of the apparent exchange interaction of the present RIP systems is positive. The total absorptive polarization observed in
the low concentration of MA is tentatively explained by the polarization transfer from the excited triplet state of carbazoles
in thermal equilibrium. 相似文献
4.
Tomoko Nii Akira Takamura Kiminori Mohri Fumiyoshi Ishii 《Colloids and surfaces. B, Biointerfaces》2003,27(4):436-332
We examined hydrogenated purified egg yolk lecithins, having practical advantages over non-hydrogenated ones, as liposomal membrane materials. Liposomes were prepared by the microencapsulation vesicle (MCV) method in which liposomes are formed through two-step emulsification and dispersion. Three types of purified egg yolk lecithins with different iodine values were examined after being dissolved in one of three lipid solvents. The liposome size increased as the temperature during the second emulsification increased, being closer to the boiling temperature of the solvent. The preparation temperature in relation to the transition temperature of each lecithin was also a factor affecting liposome sizes. As for the encapsulation efficiencies of the model compound calcein in liposomes, they differed mainly depending on the solubility of each lecithin in a lipid solvent and it was more obvious in hydrogenated lecithins. A high preparation temperature resulted in lower encapsulation efficiencies, suggesting that leakage of encapsulated calcein was facilitated at high temperature in the MCV methods. There was a significant correlation between liposome sizes and encapsulation efficiencies in non-hydrogenated purified egg yolk lecithin but not in hydrogenated ones. When using hydrogenated purified egg yolk lecithins as liposomal membrane materials, it was suggested that a lipid solvent should be chosen so that a lecithin completely dissolves under the preparation condition in order to achieve a higher encapsulation efficiency. Smaller liposome particles were obtained when the second emulsification was performed at a lower temperature compared with the boiling point of the lipid solvent. These findings can be applied to control encapsulation efficiencies and particle sizes in each particular liposome preparation enclosing therapeutic agents. 相似文献
5.
γ-irradiated acetone in polycrystalline CCl3F at 77 K has been studied by ESR to reveal that the acetone molecules tend to be oriented in CCl3F Matrix upon freezing the solution in ESR tubings. At higher concentrations both monomer and dimer radical cations of acetone are produced. The dimer cation is responsible for the optical absorption with λmax ≈ 740 nm. 相似文献
6.
Yoko M. NAKAO Takashi MIYAWAKI Shinji YASUNO Kazuhiro NAKAO Sachiko TANAKA Midori IDA Masakazu HIRATA Masato KASAHARA Kiminori HOSODA Kenji UESHIMA Kazuwa NAKAO 《Proceedings of the Japan Academy. Series B, Physical and biological sciences》2012,88(8):454-461
Objective: To investigate the significance of intra-abdominal fat area (IAFA) on new onset of individual components of the metabolic syndrome: high blood pressure, dyslipidemia, or hyperglycemia. Methods: We conducted a longitudinal study using checkup data of a hospital from 1994 to 2010. Of 25,255 subjects, we examined 1,380 Japanese, who underwent computed tomography to measure IAFA and had no metabolic syndrome components at baseline. Results: During 3.6 years of the mean follow-up period, one of metabolic syndrome components occurred in 752 subjects. Of three components, high blood pressure was more prevalent. The multiple Cox regression analysis disclosed that IAFA is significantly associated with onset of metabolic syndrome components (HR: 1.05 per 10 cm2, 95%CI: 1.03–1.07). This finding was independent of BMI, and significant even in non-obese individuals with body mass index <25 kg/m2. Conclusions: MERLOT study demonstrates that IAFA is an independent predictor for new onset of individual components of the metabolic syndrome, even in non-obese healthy Japanese. 相似文献
7.
Ultraviolet second-harmonic generation in first-order periodically poled MgO:LiNbO3 is presented. Using a high-voltage multipulse application method, we fabricated a first-order nonlinear grating with a period of 1.8 microm and depth of approximately 150 microm over 10-mm interaction length in a 1-mm-thick MgO:LiNbO3 substrate. In a single-pass configuration, continuous-wave 30-mW UV light at 362.5 nm was generated for a fundamental power of 522 mW, corresponding to a normalized conversion efficiency of 11%/W. 相似文献
8.
A 1,3,5-substituted benzene platform has been widely used in the fields of supramolecular chemistry and molecular recognition. Here, we show that 1,3,5-tris(2-benzyl-o-carboran-1-yl)benzene 6 exhibits solvent-dependent conformation in the crystalline state. Recrystallization from dichloromethane-n-pentane gave the anti conformation 6-anti, while recrystallization from methanol-acetone gave the syn conformation 6-syn, in which the three benzyl-o-carboranyl moieties are located to one side of the central benzene ring. Interestingly, one acetone molecule is captured in the π-rich space of 6-syn and two complexes facing each other encapsulate two acetone molecules in a π-rich container formed by the eight benzene rings. The inclusion involves several weak interactions, that is, T-shaped C-H···π interactions, and C-H···O and C-H···π interactions. Two C-H···O interactions involving benzylic C-H hydrogens activated by the electron-withdrawing character of the o-carborane cage and the oxygen atom of the acetone seem to be the most important. DFT calculations indicate that the binding energy for entrapment of acetone is 6.6 kcal/mol. Inclusion of acetone is achieved through not only multiple C-H···O interactions but also a number of C-H···π interactions. The third benzyl-o-carborane moiety is fixed in the syn conformation by intramolecular and intermolecular C-H···π interactions. 相似文献
9.
Kiminori Itoh Tohru Okamoto Shuhei Wakita Hiroshi Niikura Masayuki Murabayashi 《应用有机金属化学》1991,5(4):295-301
Thin films of peroxohetero(carbon)polytungstic acid (CW-HPA) and carbon-free isopolytungstic acid (W-IPA) were prepared, and examined in terms of optical and etching properties. Thermal decomposition was found to give good results in removing excess hydrogen peroxide (H2O2) during the preparation of CW-HPA and W-IPA. It was shown for the first time that thin films of CW-HPA and W-IPA have very high refractive indices (larger than 2.0) when sufficiently dried. Optical waveguide (OWG) characteristics of these films were examined using a slab-type OWG structure and ARROW (Antiresonance Reflection Optical Waveguide)-type structures. An embossing technique was applied to make diffractional grating couplers. 相似文献
10.
The fabrication of a periodic domain inversion in LiTaO3 and LiNbO3 using direct ion-beam writing is presented. The polarization of these materials can be reversed at room temperature by irradiating Si2+ ions into +c faces. A first-order periodic domain inversion with a 50% duty cycle, a depth of 300μ, and an interaction length of 1 mm was realized in LiTaO3. Using this structure, 300μW of blue light was generated for a conversion efficiency of 0.25%/W. 相似文献