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排序方式: 共有112条查询结果,搜索用时 15 毫秒
1.
Adsorption characteristics of bisphenol A onto carbonaceous materials produced from wood chips as organic waste 总被引:1,自引:0,他引:1
Nakanishi A Tamai M Kawasaki N Nakamura T Tanada S 《Journal of colloid and interface science》2002,253(2):393-396
A single-chain amphiphile containing a rigid Schiff base segment, 3-cyano-N-benzylidene hexadecylamine (CNBHB) in the polar head group was synthesized and studied for its vesicle-forming properties. The dependence of the aggregation behavior of the vesicles as such and in the presence of manganese ions were studied as a function of temperature using differential scanning calorimetry and turbidity measurements. Transmission electron microscopy (TEM) was used to analyze the morphology of the vesicles, showed interesting features with fusion of regular structures, and were quite stable. In the presence of manganese ions, fusion of vesicles takes place. This could be due to the metal ions that are bound to the surface of the vesicles that cause a partial destruction of the hydration shell on the surface of the vesicles. The reduction in the hydration force could thus be responsible for the fusion. 相似文献
2.
Fujita M Nakao Y Matsunaga S Seiki M Itoh Y Yamashita J Van Soest RW Fusetani N 《Journal of the American Chemical Society》2003,125(51):15700-15701
A novel MMP inhibitor, ageladine A (1) with antiangiogenic activity was isolated from a marine sponge Agelas nakamurai. Structure 1 was determined by a combination of spectroscopic and chemical methods to be an unprecedented structure of 4-(4,5-dibromo-1H-pyrrol-2-yl)]-1H-imidazo[4,5-c]pyridin-2-amine. 相似文献
3.
[reaction: see text] Chiral C(4)-substituted (E)- or (Z)-1-alkynyl-1-trimethylsilyloxy-2-butene systems provide anti-(Z) or syn-(Z) conjugated dienyne, with a very high level of stereocontrol, on treatment with BF(3).OEt(2) in CH(2)Cl(2) at -50 degrees C in the presence of allyltrimethylsilane. The Cieplak conformation for (E)-substrates and neighboring-group participation for (Z)-substrates are considered to be responsible for the stereochemical consequences. 相似文献
4.
Hideo?AkisadaEmail author Masakatu?Ishihara Mitiko?Nishi Masaaki?Higake Seiki?Ishimaru Junko?Nishida 《Colloid and polymer science》2003,281(10):993-997
The partial molal volumes of two series of homologous surfactants, n-alkylammonium decanesulfonates and a, ?-alkanediammonium nonanesulfonates, were measured below and above their CMC in aqueous solution. Their counterions were n-alkylammonium and a, ?-alkanediammonium. The relationship between the partial molal volume and the chain length of the counterion below the CMC had an inflection point. The relationship between them, above the CMC, was almost linear. In the case of the alkylammonium salts, the values of the volume change of micellization were almost the same when the chain length of the counterions was shorter than the butyl, and increased with an increase in the chain length when it was longer than the propyl. In the case of the alkanediammonium salts, the volume change of micellization showed a small decrease with the chain length when it was shorter than octane, and was very large for the nonane ammonium salt. The large positive increase in the volume change with the increase in the chain length of the counterion can be explained by the hydrophobic interaction between the alkyl chain of the counterion and the hydrophobic core of the micelle. 相似文献
5.
[reaction: see text] This paper describes a novel method to synthesize a quinoline backbone by incorporating allenyl cations into a catalytic intramolecular Friedel-Crafts reaction. The initial products were isomerized and aromatized upon treatment with acid and base, respectively, to give quinolines. The basic concept also proved to be promising for 1-benzazepine, 1-benzazocine, or isoquinoline synthesis. 相似文献
6.
Murrae J. Bowden Antoni S. Gozdz Joseph M. DeSimone James E. McGrath Seiki Ito Minoru Matsuda 《Macromolecular Symposia》1992,53(1):125-137
The various chemical approaches aimed at improving the reactive-ion etch resistance of poly(olefin sulfone)s are described. Resist systems based on incorporation of RIE-resistant moieties via random copolymerization, blending and block copolymer formation are described and lithographic properties noted. 相似文献
7.
Removal of phosphate by aluminum oxide hydroxide 总被引:17,自引:0,他引:17
Tanada S Kabayama M Kawasaki N Sakiyama T Nakamura T Araki M Tamura T 《Journal of colloid and interface science》2003,257(1):135-140
The development and manufacture of an adsorbent to remove phosphate ion for the prevention of eutrophication in lakes are very important. The characteristics of phosphate adsorption onto aluminum oxide hydroxide were investigated to estimate the adsorption isotherms, the rate of adsorption, and the selectivity of adsorption. Phosphate was easily adsorbed onto aluminum oxide hydroxide, because of the hydroxyl groups. The adsorption of phosphate onto aluminum oxide hydroxide was influenced by pH in solution: the amount adsorbed was greatest at pH 4, ranging with pH from 2 to 9. The optimum pH for phosphate removal by aluminum oxide hydroxide is 4. The selectivity of phosphate adsorption onto aluminum oxide hydroxide was evaluated based on the amount of phosphate ion adsorbed onto aluminum oxide hydroxide from several anion complex solutions. It is phosphate that aluminum oxide hydroxide can selectively adsorb. The selectivity of phosphate onto aluminum oxide hydroxide was about 7000 times that of chloride. This result indicated that the hydroxyl groups on aluminum oxide hydroxide have selective adsorptivity for phosphate and could be used for the removal of phosphate from seawater. 相似文献
8.
An optical sensor using a quartz core microcantilever was fabricated by etching clad layer from optical fiber. The temperature dependence of the resonance frequency of this sensor was measured in atmosphere and water. The temperature coefficient of the resonance frequency in water was 1.3×10−3/°C, which was about one order larger than that (2.3×10−4/°C) in atmosphere. This was caused by increase of additional mass due to temperature dependence of the viscosity of water, while, the increase of the resonance frequency in atmosphere was caused by temperature dependence of Young’s modulus of the quartz core. These results were evaluated theoretically using a “string-of-beads” model. 相似文献
9.
Although the Hall coefficient R(H) is an informative transport property of metals and semiconductors, its meaning in the cuprate superconductors has been ambiguous because of its unusual characteristics. Here we show that a systematic study of R(H) in La2-xSrxCuO4 single crystals over a wide doping range establishes a qualitative understanding of its peculiar evolution, which turns out to reflect a two-component nature of the electronic structure caused by an unusual development of the Fermi surface recently uncovered by photoemission experiments. 相似文献
10.
Magnetic-field-induced ordering of electrons around vortices is a striking phenomenon recently found in high-T(c) cuprates. To identify its consequence in the quasiparticle dynamics, the magnetic-field (H) dependence of the low-temperature thermal conductivity kappa of La(2-x)SrxCuO4 crystals is studied for a wide doping range. It is found that the behavior of kappa(H) in the subkelvin region changes drastically across optimum doping, and the data for underdoped samples are indicative of unusual magnetic-field-induced localization of quasiparticles; this localization phenomenon is probably responsible for the unusual "insulating normal state" under high magnetic fields. 相似文献