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排序方式: 共有296条查询结果,搜索用时 15 毫秒
291.
Katsumata K Ohno Y Tomita K Sakai M Nakajima A Kakihana M Fujishima A Matsushita N Okada K 《Photochemistry and photobiology》2011,87(5):988-994
Titanium dioxide thin films were prepared by using four water-soluble titanium complexes of titanium-lactate, tartalate, malate and salicylate complex solutions. The crystalline phases detected in the films were anatase. The surface microstructures of the four film samples were different in their grain sizes. Photocatalytic decomposition activity of the four films was almost the same, but their photoinduced hydrophilicities were different. The film prepared using titanium-salicylate complex exhibited lower hydrophilic conversion rate than the other films. Grain size and stress yielded to the film are considered to be important factors on the photoinduced hydrophilicity. 相似文献
292.
Fujii S Suzaki M Armes SP Dupin D Hamasaki S Aono K Nakamura Y 《Langmuir : the ACS journal of surfaces and colloids》2011,27(13):8067-8074
Submicrometer-sized pH-responsive sterically stabilized polystyrene (PS) latex particles were synthesized by dispersion polymerization in isopropyl alcohol with a poly[2-(diethylamino)ethyl methacrylate]- (PDEA-) based macroinitiator. These PDEA-PS latexes were extensively characterized with respect to their particle size distribution, morphology, chemical composition, and pH-responsive behavior. Millimeter- and centimeter-sized "liquid marbles" with aqueous volumes varying between 15 μL and 2.0 mL were readily prepared by rolling water droplets on the dried PDEA-PS latex powder. The larger liquid marbles adopted nonspherical shapes due to gravitational forces; analysis of this deformation enabled the surface tension to be estimated. Scanning electron microscopy and fluorescence microscopy studies indicated that flocs of the PDEA-PS particles were adsorbed at the surface of these water droplets, leading to stable liquid marbles. The relative mechanical integrity of the liquid marbles prepared from alkaline aqueous solution (pH 10) was higher than those prepared from acidic aqueous solution (pH 2) as judged by droplet roller experiments. These liquid marbles exhibited long-term stability (over 1 h) when transferred onto the surface of liquid water, provided that the solution pH of the subphase was above pH 8. In contrast, the use of acidic solutions led to immediate disintegration of these liquid marbles within 10 min, with dispersal of the PDEA-PS latex particles in the aqueous solution. Thus the critical minimum solution pH required for long-term liquid marble stability correlates closely with the known pK(a) value of 7.3 for the PDEA stabilizer chains. Stable liquid marbles were also successfully prepared from aqueous Gellan gum solution and glycerol. 相似文献
293.
Berhal F Takechi S Kumagai N Shibasaki M 《Chemistry (Weinheim an der Bergstrasse, Germany)》2011,17(6):1915-1921
In an attempt to explore the synthetic utility of a ternary asymmetric catalyst comprising La(NO3)3?6H2O, amide‐based ligand (R)‐ L1 , and D ‐valine tert‐butyl ester H‐D ‐Val‐OtBu, we investigated a catalytic, asymmetric amination of functionalized N‐nonsubstituted α‐alkoxycarbonyl amides using di‐tert‐butyl azodicarboxylate as an electrophilic aminating reagent. A highly functionalized, cyclic N‐nonsubstituted α‐alkoxycarbonyl amide delivered the desired amination product in up to 96 % enantiometric excess, with the requisite functionalities of the polar heads of sphingosines with the appropriate stereochemical arrangement. The rapid asymmetric assembly of these functional groups allowed a concise enantioselective synthetic route to sphingosines to be established with a broad flexibility towards derivative synthesis. These studies have culminated in an efficient catalytic enantioselective total synthesis of immunosuppressive fungal metabolites mycestericin F ( 3 a ) and G ( 3 b ). 相似文献
294.
Sho Inoue Nguyen T. NamNguyen N. Phuoc Jiangwei CaoHnin Yu Yu Ko Takao Suzuki 《Journal of magnetism and magnetic materials》2008
The magnetic and magneto-optical properties of FeRh thin films epitaxially deposited onto MgO(1 0 0) substrates by RF sputter-deposition system have been investigated in conjunction with the structure. An intriguing virgin effect has been found in the M–T curves of the as-deposited FeRh thin films, which is presumably interpreted in term of a change in structural phase when heating. Also, a (negative) maximum peak of Kerr rotation at around 3.8 eV has been observed when FeRh thin films are in ferromagnetic state. The polar Kerr rotation angle is found to increase at temperatures above 100 °C, which corresponds to the antiferromagnet (AF)–ferromagnet (FM) transition of FeRh thin films. 相似文献
295.
Onda K Ogihara S Yonemitsu K Maeshima N Ishikawa T Okimoto Y Shao X Nakano Y Yamochi H Saito G Koshihara SY 《Physical review letters》2008,101(6):067403
The quasistable state in the photoinduced phase transition for the quasi-one-dimensional quarter-filled organic conductor (EDO-TTF)2PF6 has been examined by ultrafast reflective measurements and time-dependent model calculations incorporating both electron-electron and electron-phonon interactions. The transient optical conductivity spectrum over a wide probe photon-energy range revealed that photoexcitation induced a new type of charge-disproportionate state. Additionally, coherent and incoherent oscillations dependent on probe photon energies were found, as predicted by the calculation. 相似文献
296.
Kazunobu Sugihara Sachiko Kaidzu Masahiro Sasaki Sho Ichioka Yuji Takayanagi Hiroshi Shimizu Ichiya Sano Katsunori Hara Masaki Tanito 《Photochemistry and photobiology》2023,99(3):967-974
Two krypton-chloride germicidal excimer lamp units (Care222 TRT-104C11-UI-U3, USHIO Inc.) were installed in the examination room of an ophthalmology department. The irradiation dose was set not to exceed the former (i.e., before 2022) threshold limit value (TLV) (22 mJ cm−2/8 h) recommended by the ACGIH. Section 1: The eyes and lids of the six ophthalmologists (5 wore glasses for myopic correction) who worked in the room for a mean stay of 6.7 h week−1 were prospectively observed for 12 months. Slitlamp examinations revealed neither acute adverse events such as corneal erosion, conjunctival hyperemia, and lid skin erythema nor chronic adverse events such as pterygium, cataract, or lid tumor. The visual acuity, refractive error, and corneal endothelial cell density remained unchanged during the study. Section 2: The irradiation of samples placed on the table or floor using the same fixtures in the room (5–7.5 mJ cm−2) was associated with >99% inhibition of φX174 phage and >90% inhibition of Staphylococcus aureus. In conclusion, no acute or chronic health effects in human participants was observed in a clinical setting of full-room ultraviolet germicidal irradiation by 222-nm lamp units, and high efficacy in deactivation of microorganisms was determined in the same setting. 相似文献