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71.
Finely patterned transparent, conductive SnO2 thin films have been prepared. UV-light from a high-pressure mercury lamp was irradiated through a mask on the precursor films prepared from SnCl2 with acetyl acetone in the ambient atmosphere, and this irradiation led to the change of solubility of the films in alkaline solution. Patterns with a width of about 3 to 50 m and thickness of about 0.1 m were formed with a pitch of about 2 to 20 m. The resistivity of the films heat-treated at 500°C after UV irradiation was about 1 × 10–2 cm, which was almost the same resisitivity for the films heat-treated at 500°C without UV irradiation.  相似文献   
72.
By the use of seed crystals in the initial stage of preparation of a new type of zeolite for olefin synthesis, shape and size distribution of the zeolite could be regulated uniformly, and the catalyst performance was improved markedly especially with respect to olefin selectivity and the catalyst life.
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73.
We have prepared superhydrophobic surfaces which become superhydrophilic by heat-treatment at 500°C or irradiation of UV-light. When hydrolyzed fluoroalkyltrimethoxysilane (FAS) was coated on Al2O3 gel film with a roughness of 20 to 50 nm, the films showed superhydrophobicity and high transparency; the contact angle for water of the film was 165° and the transmittance for the visible light was higher than 92%. When the FAS-coated thin films were heat-treated at temperatures higher than 500°C, the films became superhydrophilic; the contact angle for water on the films was smaller than 5°. Thin films of amorphous TiO2 or anatase TiO2 were coated between Al2O3 gel and FAS layer, and the contact angle for water was also about 160°. UV irradiation using high-pressure mercury lamp on these films resulted in the contact angle to be smaller than 5°. When UV light was irradiated through a photomask, superhydrophobic-superhydrophilic micropatterns applicable as a stamper for printing or a substrate of micro-optical components were successfully obtained on the films.  相似文献   
74.
75.
Fluorescence spectra of Ce3+ ions in silicate, borate, and phosphate glasses melted in Ar were measured. The relative fluorescence intensity of Ce3+ in the ultraviolet region increased in the order of R = Ba, Ca, Sr, and Mg in the 20Li2O-20RO-60SiO2 glass samples and with decreasing BaO content in the BaO-B2O3 glass samples, respectively. In contrast, the relative fluorescence intensity of Ce3+ did not change with varying the glass composition in phosphate glass samples. The compositional dependence of the relative fluorescence intensity of Ce3+ is discussed in terms of redox reaction of Ce3+-Ce4+ in oxide glasses.  相似文献   
76.
Amphiphilic, star‐shaped copolymers were synthesized by the ring‐opening polymerization of trimethylene carbonate initiated with a trifunctional, poly(ethylene glycol)‐based surfactant (polyoxyethylene sorbitan monolaurate) in the absence of any catalysts. The metal‐ and solvent‐free polymerization proceeded at 150 °C and afforded polyoxyethylene sorbitan monolaurate‐block‐poly(trimethylene carbonate) with number‐average molecular weights of 4500–11,900 in excellent yields. The copolymers successfully dispersed in a water/ethyl acetate (10/1 v/v) mixture, and the uniform suspension could contain a hydrophobic pigment and pyrene. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 6633–6639, 2006  相似文献   
77.
A methacrylate having a hydrophilic poly(ethylene glycol) chain and 2‐(N,N‐dimethylamino)ethyl methacrylate were radically copolymerized to obtain a statistical hydrophilic copolymer having tertiary amino groups in the side chains. The obtained polymeric amine was quantitatively quaternarized by a benzyl chloride‐type molecule having an acetal moiety derived from geraniol, which is a hydrophobic alcohol widely used as a fragrance ingredient. The resulting copolymer, which had PEG chain and the quaternary ammonium moieties as hydrophiles and the acetal moieties as hydrophobes, exhibited amphiphilicity to form stable associates in water. The acetal moieties were stable for 30 days at pH 9, while they were gradually hydrolyzed at pH 4 to release geraniol continuously at least for 30 days, confirming the potential applicability of the copolymer to a controlled releasing system of functional molecules. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 3241–3247, 2009  相似文献   
78.
The influence of a deformation of the triton due to a non-s part of the ground state wave function on triton induced reactions is investigated. For this purpose, a measurement of the absolute cross section of the197Au(t, d)198Au reaction below 7 MeV was performed and compared with a finite range DWBA calculation. Implications on reactions with tritons during the primordial nucleosynthesis are briefly discussed.  相似文献   
79.
The characteristics of radiation detector fabricated by stacking some piezoelectric lead zirconate titanate (PZT) elements were studied by irradiating it with a 400 MeV/n xenon (Xe) beam. Comparing between observed results from the detector and calculation results using Bethe–Bloch formula, it was found that the amplitude of the output voltage observed was dependent on the amount of ionization energy loss of Xe ion with PZT.  相似文献   
80.
4-Formyl-2-methyl-1,3,4-thiadiazolin-5-thione, prepared from acetic formic anhydride, is found to act as a selective formylation reagent under mild conditions. The synthesis of some N-formyl antibiotics with this reagent is reported.  相似文献   
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