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71.
Singlet oxygen was generated by reaction of sodium hypochlorite and hydrogen peroxide in a micro-channel. The two reagent solutions were delivered into the micro-channel by a syringe pump, providing a laminar flow liquid-liquid interface. The chemiluminescence from the singlet oxygen was emitted in the collapse of the interface due to molecular diffusion under laminar flow conditions. The chemiluminescence intensity was observed continuously and stably for each combination of reagents fed into the micro-channel; while, in the normal batch-type reactor the chemiluminescence peaks from singlet oxygen were observed within ca. 5 s. The features of the chemiluminescence emitted under laminar flow conditions were examined by changing the concentrations of sodium hypochlorite and hydrogen peroxide; the concentrations of 2.5 mM sodium hypochlorite and 7.5 mM hydrogen peroxide provided highest chemiluminescence intensities without bubble formation. Also, the effects of beverages, such as green tea, coffee, white wine, red wine, and sake (rice wine), on the chemiluminescence intensity as well as the concentrations of sodium hypochlorite and hydrogen peroxide were examined. The chemiluminescence intensities observed with addition of the beverages to the reagents decreased in the following orders; green tea > coffee > red wine > rice wine > white wine (being added to sodium hypochlorite); coffee > white wine > green tea > red wine > rice wine (being added to hydrogen peroxide). It was found that coffee decreased the chemiluminescence intensity (ca. 33% chemiluminescence decrease) without altering the concentrations of sodium hypochlorite or hydrogen peroxide. The cause of the decrease in chemiluminescence with coffee is discussed. 相似文献
72.
Production of micron-sized monodispersed composite polymer particles by seeded polymerization utilizing the dynamic swelling method 总被引:1,自引:0,他引:1
In order to develop the seeded polymerization technique utilizing the dynamic swelling method (DSM) proposed by authors for
the production of micron-sized mono-dispersed “composite” polymer particles consisting of two kinds of polymers, the seeded
polymerization for the dispersion of ethyl methacry-late (EMA)-swollen PS particles prepared utilizing DSM was carried out.
Monodispersed PS/poly(ethyl methacrylate) (PEMA) composite particles having 7 μm in diameter were produced by the addition
of NaCl to lower the solubility of EMA in medium and by the addition of CuCl2 as a water-soluble inhibitor to depress the by-production of submicron-sized PEMA particles.
Received: 16 July 1996 Accepted: 10 October 1996 相似文献
73.
Masao Ikeda Takashi Nakamura Yu Nagase Koji Ikeda Yoshiro Sekine 《Journal of polymer science. Part A, Polymer chemistry》1981,19(10):2595-2607
For the purpose of studying the mechanism of thermal degradation of poly[(tetramethyl-p-silphenylene) Siloxane] (poly TMPS) a series of polymers with silphenylene and siloxane bonds in the main chain were prepared and subjected to thermogravimetry (TG) and pyrolysis study. Analyses of products from poly TMPS degradation (in vacuum at a constant temperature) by gas chromatography (GC), infrared (IR), nuclear magnetic resonance (NMR) spectroscopy, and gas chromatography-mass spectrometry (GC–MS) revealed that degradation occurs at the silphenylene bonds. The TG curves obtained in He for heating rates of 1,2,2.5,7.5, and 10°C/min were analyzed by the Ozawa method; activation energies of 39 ± 1 and 45 ± 2 kcal/mol were obtained respectively for the initial cleavage of the methyl side group and the later-stage scission of the main-chain silphenylene bond which leads to a major weight loss. The results agree with those obtained for other structurally similar polymers. 相似文献
74.
Adsorptions of N(2), H(2)O, and organic vapors including CH(2)Cl(2), CCl(4), c-C(6)H(12), C(6)H(6), n-C(6)H(14), and n-C(9)H(20) on a silica-pillared layered manganese oxide (SiHMnO) and nonane-preadsorbed SiHMnO were examined. It is found that SiHMnO has a microporosity with a wide pore width distribution showing different pore wall affinities. Micropores with smaller width preferentially accommodate the nonane preadsorbate while the surface hydrophilicity of pore wall leads to an easier detachment of the adsorbed nonane molecules. H(2)O adsorption influences both the porosity and the surface properties by accelerating a sufficient hydrolysis of the remained TEOS molecules in SiHMnO. Examinations using Dubinin-Radeshkevich (DR) equation and isosteric heat of adsorption of organic molecules provide evidences that the wall surface of micropores with smaller and larger width have less affinity toward nonpolar and polar organic vapors, respectively. 相似文献
75.
Koichi Shiomi Masao Shimono Hiromi Arimoto Seiji Takahashi 《Journal of separation science》1991,14(11):729-737
A slightly modified, commercially available high resolution capillary gas chromatograph and a PC-based data processing system running proprietary software (“PONA”) have been employed in the development of a system for petroleum type analysis which would be equivalent or superior to the FIA (fluorescent indicator adsorption) method in terms of ease of use and the speed, variety, and accuracy of the analytical data produced. The system is capable of performing identification and quantitation of most of the individual components in a complex gasoline sample consisting of more than 230 components and can report weight percentage and/or volume percentage for each component as well as types by carbon number (e.g., isoparaffins, normal paraffins, olefins, naphthenes, aromatic compounds) within a ca. 70 minute analysis cycle. Precolumn sulfonation to trap olefins and aromatic compounds has been used as an complementary technique to the basic mass spectrometric identification of components of interest. The estimation of correction factors for weight percentage (or volume percentage) calculation are also discussed. Comparisons are made between this system and others, and the results indicate that the proposed method supersedes the conventional method employing FIA. 相似文献
76.
5-Fluorouracil derivatives with serum protein binding potencies 总被引:1,自引:0,他引:1
S Yamashita Y Suda M Masada T Nadai M Sumi 《Chemical & pharmaceutical bulletin》1989,37(10):2861-2863
To develop an optimal delivery system for 5-fluorouracil (5FU) using serum protein as a drug carrier, a series of its benzyl derivatives was synthesized. Then their binding to the serum protein was investigated by equilibrium dialysis. The benzyl derivatives of 5FU were strongly bound to rat plasma protein or human serum albumin. The bound percentage increased with increasing hydrophobicity. It was suggested that the benzyl derivative of 5FU existed in the blood as a complex with serum albumin and circulated for a long time as a polymeric drug does. 相似文献
77.
An epoxy-group-containing polymer chain was grafted onto the hollow-fiber form of a porous polyethylene membrane by the immersion of the electron beam-irradiated trunk polymer in glycidyl methacrylate diluted with methanol and 1-butanol. The epoxy group density ranged from 8.5 to 13.4 mol per kg of the trunk polymer. Subsequently, the epoxy groups produced were converted into sulfonic acid and diethylamino groups. The density of -SOH and -N(C2H5), groups was 0.40 and 2.2 mol per kg of the product. respectively. The polymer brush, defined as a polymer chain extending from the surface of a pore toward the interior of the pore, was evaluated from the determination of an equilibrium binding capacity of hen egg lysozyme (HEL) and bovine serum albumin (BSA). The polymer brush prepared in 1-butanol was found to be longer than that prepared in methanol from the determinations of liquid permeability and protein adsorptivity. The proteins were bound to the polymer brush prepared in 1-butanol, followed by the functionalization, at higher degrees of multilayer binding: about 30 for HEL and 6 for BSA. 相似文献
78.
[reaction in text] The first total synthesis of (+/-)-linderol A, a hexahydrodibenzofuran isolated from Lindera umbellata bark, with potent inhibitory activity on melanin biosynthesis of cultured B-16 melanoma cells was achieved via a 20-step of reaction in 7.64% overall yield starting from 4,6-dimethoxysalicylaldehyde. 相似文献
79.
As a new concept for the design of effective photocatalysts, an ion beam technology using accelerated metal ions, a metal ion implantation and an ionized cluster beam (ICB) method, have been applied to design unique photocatalysts. The metal ion implantation of TiO2 and Ti-containing zeolites with highly accelerated metal ions (V+, Cr+, etc.) is useful in designing photocatalysts that can operate efficiently under visible light irradiation. Also, an ICB method with a low acceleration energy is useful in preparing transparent TiO2 thin films on various types of substrates for the efficient photocatalytic degradation of pollutants diluted in water and air. The combination of the ICB method and metal ion implantation can develop the TiO2 thin films that are able to operate not only under UV light but also under visible light irradiation. 相似文献
80.
Meso and racemic isomers of 1,1′-bis(α-hydroxyalkyl)ferrocene derivatives, and trans and cis isomers of 7-oxa[3]ferrocenophanes have been isolated. The configurations of these isomers have been determined both by spectroscopy and from their reaction behavior. It has been found that the ring-closure and ring-opening interconversion reactions between 1,1′-bis(α-hydroxyalkyl)ferrocenes and 7-oxa[3]ferrocenophanes are stereospecific. PMR spectra of the diols and ethers have been examined at 100 MHz in CF3COOH, and the existence of α-[1′-(α-hydroxyalkyl)ferrocenyl]carbonium ions has been demonstrated in this acid. A mechanism for the various interconversion reactions is proposed on the basis of their stereospecific reactivity and from the PMR spectra of the carbonium ions. 相似文献