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11.
Kuroda N Sako A Ohyama K Akiyama S Nakashima K 《Journal of chromatographic science》2005,43(3):116-120
Modified 3-aminopropylsilyl silica stationary phases with 1,8-naphthalic anhydrides [3-(1,8-naphthalimido)propyl (NAIP), 3-(4-amino-1,8-naphthalimido)propyl (4A-NAIP), 3-(3-nitro-1,8-naphthalimido)propyl (3N-NAIP), and 3-(4-nitro-1,8-naphthalimido)propyl modified silyl silica gel (4N-NAIP)] are prepared in a single reaction. Chromatographic properties of these phases are characterized using various solutes including monosubstituted benzenes, alkyl benzenes, and polycyclic aromatic hydrocarbons (PAHs) in high-performance liquid chromatography. Even though the retention in these NAIPs is mainly based on the reversed-phase mode, 3N- and 4N-NAIP show a remarkable recognition toward aromatic hydrocarbons, which is attributed to their strong pi-pi interaction. Furthermore, the recognition ability is according to the molecular planarity and non-linearity of PAHs. Subsequently, 3N- and 4N-NAIP has a distinct selectivity from octadecyl silica and, therefore, will be a valuable alternative for a separation or a solid-phase extraction of aromatic compounds. 相似文献
12.
Polymer-protected platinum/ruthenium colloidal dispersions were prepared by refluxing mixed solutions of hexachloroplatinic(IV) acid and ruthenium(III) chloride in a mixture of ethanol/water (1/1 v/v) in the presence of poly(N-vinyl-2-pyrrolidone). The electronic spectra and transmission electron micrographs suggested that the colloidal dispersions are almost composed of the mixture of the small monometallic Pt and Ru clusters over all the ratio of Pt/Ru compositions. Extended X-ray absorption fine structure analyses and high resolution electron microprobe analyses indicated that no Pt/Ru alloy clusters exist in the dispersions, and the aggregation occurs between small monometallic Pt clusters (diameter ca. 15 A) and partially oxidized Ru microclusters (diameter less than 10 A). Electron diffraction measurements also suggested that the diffraction pattern of aggregated Pt/Ru cluster particles prepared by the simultaneous reduction of Pt and Ru ions is the same as that of the physical mixture of the small monometallic Pt and Ru clusters separately prepared. Therefore, it can be concluded that the aggregated Pt/Ru cluster particles, with 10 to 60 A in diameter, are built up by small monometallic Pt clusters and partially oxidized Ru microclusters, and that Pt/Ru alloy clusters are not formed. 相似文献
13.
Hashizaki K Taguchi H Itoh C Sakai H Abe M Saito Y Ogawa N 《Chemical & pharmaceutical bulletin》2005,53(1):27-31
Poly(ethylene glycol)-grafted liposomes (PEG-liposomes) were prepared from dipalmitoylphosphatidylcholine (DPPC) with various amounts of distearoyl-N-monomethoxy poly(ethylene glycol)-succinyl-phosphatidylethanolamines (DSPE-PEG) with PEG molecular weights of 1000, 2000, 3000 and 5000. The effects of DSPE-PEG concentration on the permeability of PEG-liposomes were investigated using carboxyfluorescein (CF). In the gel state, the CF leakage from PEG-liposomes was decreased with increasing mole fractions of DSPE-PEG for all PEG molecular weights. In the liquid-crystalline state, the CF leakage from PEG-liposomes containing DSPE-PEG1000 gradually increased with increasing mole fractions of DSPE-PEG, while that of PEG-liposomes whose molecular weight in PEG units was above 2000 rapidly decreased by the addition of DSPE-PEG. Furthermore, no effect of PEG molecular weight on CF leakage was observed. The relationship between the fluorescence polarization of 1,6-diphenyl-1,3,5-hexatriene (DPH) (or 1-(4-trimethylammoniumphenyl)-6-phenyl-1,3,5-hexatriene (TMA-DPH)) and the mole fraction of DSPE-PEG for PEG-liposomes was also investigated. No significant changes in fluorescence polarization of DPH for liposomal bilayer membranes was observed in the gel and liquid-crystalline states due to the addition of DSPE-PEG, while that of TMA-DPH was decreased compared with that of liposomes without DSPE-PEG in both states. 相似文献
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17.
Masunobu Maeda Yoshiaki Kinjo Osamu Hisada Kaname Ito 《Journal of solution chemistry》1990,19(10):1019-1027
The Pitzer approach has been applied to the evaluation of dissociation constants of ammonium ion in lithium perchlorate and lithium chloride-sodium chloride mixed solutions at 25°C. The calculated values showed good agreement with the observed values, provided all the higher-order interaction terms ('s and 's) concerned were introduced. The unknown (NH4LiClO4) value was determined from the isopiestic measurements of NH4ClO4–LiClO4 mixed solutions. Parameters in the Pitzer formalism for ammonia-ion interactions involved in LiCl and NaCl media were determined by use of the activity coefficients of ammonia measured in LiCl–NaCl mixed solutions by a transpiration method. 相似文献
18.
Self-assembling structures of long-chain phenyl glucoside influenced by the introduction of double bonds 总被引:1,自引:0,他引:1
Jung JH John G Yoshida K Shimizu T 《Journal of the American Chemical Society》2002,124(36):10674-10675
Four long-chain phenyl glucoside amphiphiles possessing a saturated or unsaturated long alkyl chain group as the self-assembling unit of a highly organized molecular architecture were synthesized. Their self-assembling properties were investigated by EF-TEM, SEM, CD, FT-IR, and XRD. Compound 2 possessing one double bond in the lipophilic portion showed twisted helical fibers, which formed a bilayered structure with a 3.59 nm period, while compound 3 showed the helical ribbons and left-handed nanotubular structures with 150-200 nm inner diameters and ca. 20 nm of wall. Very interestingly, compound 4 possessing three double bonds showed a nanotubular structure with ca. 70 nm of inner diameter through a helical ribbon, which formed a loose bilayered structure with 4.62 nm. These results indicate that self-assembling properties strongly depend on the number of cis double bonds. 相似文献
19.
Ryuichi Iemura Tsuneo Kawashima Toshikazu Fukuda Keizo Ito Goro Tsukamoto 《Journal of heterocyclic chemistry》1987,24(1):31-37
Several types of benzimidazole derivatives were prepared and were screened for H 1-antihistaminic activity. Most of the compounds showed potent antihistaminic activity in vitro. Among them 2-[(1-piperazinyl)methyl]-benzimidazoles 14 and 2-[(1-homopiperazinyi)methyl]benzimidazoles 15 exhibited potent activity also in vivo. 相似文献
20.
Carbon dioxide fixation by microalgae photosynthesis using actual flue gas discharged from a boiler 总被引:2,自引:0,他引:2
Matsumoto Hiroyo Shioji Norio Hamasaki Akihiro Ikuta Yoshiaki Fukuda Yoshinori Sato Minoru Endo Noriyoshi Tsukamoto Toshiaki 《Applied biochemistry and biotechnology》1995,(1):681-692
To mitigate CO2 discharged from thermal power plants, studies on CO2 fixation by the photosynthesis of microalgae using actual exhaust gas have been carried out. The results are as follows.
相似文献
1. | A method is proposed for evaluating the maximum photosynthesis rate in the raceway cultivator using only the algal physical properties; |
2. | Outdoor cultivation tests taking actual flue gas were performed with no trouble or break throughout 1 yr using the strain collected in the test; |
3. | The produced microalgae is effective as solid fuel; and |
4. | The feasibility studies of this system were performed. The system required large land area, but the area is smaller than that required for other biomass systems, such as tree farms. |