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21.
A novel fine particle removal system composed of a corona-discharge neutralizer, a pulse-jet air unit and an image processing system has been developed. First of all, adhesion force between particle and film was directly measured and effect of electrostatic force on the adhesion force was calculated experimentally and theoretically. The electrostatic force was found to be significant, leading to the suggestion that the countermeasure for the electrostatic force was required to effectively remove fine particles. This system was then applied to the removal of fine particles from surface of a gelatin film used for conventional capsule material. The number of particles removed by the system was calculated by an image processing system and number base removal efficiency was computed with and without the elimination of electrostatic charge by the neutralizer. It was found that the difference between the removal efficiency of particles with elimination of electrostatic charge and that of without the elimination showed linear relationship with the electrostatic adhesion force. The data confirmed the necessity of electrostatic charge elimination for the effective removal of fine particles. 相似文献
22.
Takenori Tomohiro Kouichi Uoto Hiroaki Okuno 《Journal of heterocyclic chemistry》1990,27(5):1233-1239
A series of macrocyclic tetraamines with 28-, 32-, 36-, 40- and 44-membered rings have been efficiently prepared from the corresponding ditosylamide and monobromoalcohol derivatives in 6 steps via a double condensation reaction. Overall yields were: 41, 41, 46, 29, and 33%, respectively, for 1,8,15,22-tetraazacyclooctacontane ( 11a ), 1,9,17,25-tetraazacyclodotriacontane ( 11b ), 1,10,19,28-tetraazacyclohexatriacontane ( 11c ), 1,11,21,31-tetraazacyclotetracontane ( 11d ) and 1,12,23,34-tetraazacyclotetratetracontane ( 11e ). 相似文献
23.
A. Miyakawa H. Takeya T. Sekine K. Yoshihara 《Journal of Radioanalytical and Nuclear Chemistry》1989,136(2):151-157
In recoil implantation reaction of51Cr in Cr/acac/3 a polymer component which was sensitive to radiation dose was found. However, a retention type component51Cr/acac/3 was not so sensitive to radiation dose. A remarkable dependence of the yield of51Cr/acac/3 on recoil energy was found in the range 102–106 eV in recoil implantation using a thin film technique. This suggests a special role of implantation reaction in solids. 相似文献
24.
Thermodynamically stable vesicle formation from glycolipid biosurfactant sponge phase 总被引:3,自引:0,他引:3
Imura T Yanagishita H Ohira J Sakai H Abe M Kitamoto D 《Colloids and surfaces. B, Biointerfaces》2005,43(2):115-121
Thermodynamically stable vesicle (L(alpha1)) formation from glycolipid biosurfactant sponge phase (L(3)) and its mechanism were investigated using a "natural" biocompatible mannosyl-erythritol lipid-A (MEL-A)/L-alpha-dilauroylphosphatidylcholine (DLPC) mixture by varying the composition. The trapping efficiency for calcein and turbidity measurements clearly indicated the existence of three regions: while the trapping efficiencies of the mixed MEL-A/DLPC assemblies at the compositions with X(DLPC)< or =0.1 or X(DLPC)> or =0.8 were almost zero, the mixed assemblies at the compositions with 0.1 or =0.8 were multilamellar vesicles (L(alpha)) with diameter from 2 to 10 microm. Meanwhile, dynamic light scattering (DLS) measurement revealed that the average size of the vesicles at the composition of X(DLPC)=0.3 was 633.2 nm, which is remarkably small compared to other compositions. Moreover, the mixed vesicle solution at the composition of X(DLPC)=0.3 was slightly bluish and turbid and kept its dispersion stability at 25 degrees C for more than 3 months, indicating the formation of a thermodynamically stable vesicle (L(alpha1)). These results exhibited the formation of a thermodynamically stable vesicle (L(alpha1)) with a high dispersibility from the MEL-A/DLPC mixture. The asymmetric distribution of MEL-A and DLPC in the two vesicle monolayers caused by the difference in geometrical structures is very likely to have changed their self-assembled structure from a sponge phase (L(3)) to a thermodynamically stable vesicle (L(alpha1)). 相似文献
25.
Dobashi T Nobe M Yoshihara H Yamamoto T Konno A 《Langmuir : the ACS journal of surfaces and colloids》2004,20(16):6530-6534
Curdlan dissolved in aqueous sodium hydroxide was dialyzed to aqueous calcium chloride to form a gel. Transparent and turbid concentric layers observed in the gel cross section perpendicular to the long axis of the dialysis tube were identified as liquid crystalline gels with refractive index gradient and amorphous gels, respectively. The thickness of each layer was proportional to the diameter of the dialysis tube, and the gelation proceeded in proportion to the root of time. The unique pattern formation was attributed to the change of curdlan conformation and calcium-induced cross-linking resulting from a diffusion of calcium cations and hydroxide anions through the dialysis tube. It is suggested that the orderedness of the curdlan molecules decreases by the increase of the curvature of the concentric liquid crystal layers as the layer comes toward the center of the dialysis tube. 相似文献
26.
A. Mutalib T. Omori K. Yoshihara 《Journal of Radioanalytical and Nuclear Chemistry》1992,165(1):19-25
A new chemical species of bis(acetonitrile)bis(acetylacetonato)technetium(III), [Tc(acac)2(CH3CN)2]+, has been prepared by the reaction of tris(acetylacetonato)technetium(III) with acetonitrile in the presence of a strong acid, perchloric or hydrochloric acid. The reaction kinetics were followed by observing spectral change of Tc(acac)3 in the UV-visible region. The complex has been characterized by combination of elemental analyses, IR and UV-visible spectrophotometry, ion-exchange chromatography, and paper electrophoresis. Applicability of this substance to synthesize mixed-ligand technetium(III) complexes was discussed based on the solubility of this complex and the ease of substitution of the acetonitrile ligand. 相似文献
27.
Hiroshi Tatewaki Tomohiro Hashimoto Kimihiko Hirao 《Theoretical chemistry accounts》1997,98(2-3):71-74
Using optimal exponents for B through Ne given by Dunning and those for Al through Ar by Woon and Dunning, d-type contracted polarization functions (2d/1d), (3d/1d), and (3d/2d) are generated from natural orbitals of atomic single and double excitation configuration interaction (SDCI) calculations,
where the numbers before and after the slash are those of the primitive and contracted Gaussian type functions. The resulting
contracted functions are tested on N2 and P2 molecules by self-consistent field and SDCI calculations, which clarify characteristics of the present polarization functions.
Received: 5 June 1997 / Accepted: 20 August 1997 相似文献
28.
An efficient method of photoaffinity labeling has been developed based on rationally designed multifunctional photoprobes. Photoaffinity techniques have been used to elucidate the protein structure at the interface of biomolecules by the photochemical labeling of interacting sites. However, the identification of labeled sites within target proteins is often difficult. Novel biotinyl bioprobes bearing a diazirine photophore have contributed significantly to the rapid elucidation of ligand binding sites within proteins, thereby extending conventional photoaffinity methods. This article discusses the synthesis and applications of various photoprobes bearing a biotin, including strategies using cleavable linkages between photophores. The combination of photoaffinity methods with chip technology is also described as a novel entry to rapid affinity-based screening of inhibitors. This review focuses on a rapid and reliable photoaffinity method utilizing diazirine-based multifunctional photoprobes with numerous potential applications in functional proteomics of biomolecular interactions. 相似文献
29.
Yoshihara T Druzhinin SI Zachariasse KA 《Journal of the American Chemical Society》2004,126(27):8535-8539
The planar rigidized molecule fluorazene (FPP) undergoes fast reversible intramolecular charge transfer (ICT) in the excited state, with a reaction time of 12 ps in the polar solvent ethyl cyanide at -45 degrees C. The ICT state of FPP has a dipole moment mu(e)(ICT) of 13 D, much larger than that of the locally excited state LE (1 D). The ICT behavior of FPP is similar to that of its flexible counterpart N-phenylpyrrole (PP), for which mu(e)(ICT) = 12 D. These results show that intramolecular charge transfer to a planar ICT state can occur efficiently. In designing ICT systems capable of rapid switching, it is therefore important to realize that large amplitude motions such as those necessary for the formation of a twisted intramolecular charge transfer (TICT) state are not required. 相似文献
30.
Hiroki Nakamura Jiro Tanaka Nobuaki Nakashima Keitaro Yoshihara 《Chemical physics letters》1981,77(2):419-421
The photoionization of 8-anilino-1-naphthalenesulfonate in polar solvents occurs through a biphotonic process, as proved by nanosecond flash photolysis. A transient absorption of a charge transfer to solvent (CTTS) state is found with ≈10 ns life-time. The state is shown to be an intermediate of the photoionization process. 相似文献