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51.
Akhtaruzzaman M Kamata N Nishida J Ando S Tada H Tomura M Yamashita Y 《Chemical communications (Cambridge, England)》2005,(25):3183-3185
Dithiazolylbenzothiadiazoles easily obtained have high electron affinity and the FET device of a trifluoromethylphenyl derivative exhibited a good n-type performance with high electron mobility. 相似文献
52.
Improved synthesis of four stereoisomeric chiral 1,3-dimethyl-1,2,3,4-tetrahydroisoquinolines (1a, b, ent-1a, b) was achieved via the super acid-induced cyclization of chiral N-[1-methyl-2-(phenylsulfinyl)ethyl]-N-(1-phenylethyl)formamides (4a, b, ent-4a, b) using the Pummerer-type cyclization reaction as a key step. The cyclization leading to the isoquinoline ring proceeded in a quantitative manner when trifluoromethane sulfonic acid (TFSA) was used as the super acid, although Friedel-Crafts-type alkylation of 4-phenylsulfanyl TIQ derivatives (5) with benzene used as the solvent accompanied cyclization to yield the 4-phenyl-TIQs (7). The byproduct (7) was exclusively formed when a large excess amount of TFSA was used. 相似文献
53.
Masumi?Sato Masahiro?Nobe Toshiaki?DobashiEmail author Takao?Yamamoto Akira?Konno 《Colloid and polymer science》2005,284(3):293-300
We have found that the dialysis of curdlan dissolved in alkaline solution into aqueous solutions of metal salts yielded multifold gel structures. Aqueous sodium chloride and potassium chloride as well as pure water induced isotropic gels. Aqueous calcium salts induced liquid crystalline gel with refractive index gradient/amorphous gel alternative structure. Aqueous salts of trivalent aluminum and ferric cations induced a rigid liquid crystalline gel, which shrank above a threshold concentration of each salt. On the other hand, Liesegang ring-like pattern was observed with aqueous solutions of mixed salts of calcium chloride and magnesium chloride. The patterns have been classified to discuss the mechanism of forming the variety of structures. 相似文献
54.
Application of the muramyldipeptide derivative B30-MDP to liposomal vaccines will aid in the development of improved high immunogenicity vaccines. To give full play to the effectiveness of B30-MDP as a liposomal vaccine, it is important to evaluate the effect of cholesterol, dimyristoylphosphatidylcholine (DMPC) or distearoylphosphatidylcholine (DSPC) incorporation on the chemical stability of B30-MDP and physicochemical properties of B30-MDP/lipid mixed vesicles from the view point of pharmaceutics.The observed degradation rate constants of B30-MDP by hydrolysis in B30-MDP/cholesterol mixed vesicles were increased with increasing concentration of cholesterol, however, those in B30-MDP/DMPC and B30-MDP/DSPC mixed vesicles were unchanged with increasing concentration of DMPC and DSPC. The degradation behavior of B30-MDP was then compared with physicochemical properties of B30-MDP/lipid mixed vesicles, such as membrane fluidity and particle size. It was apparent that the degradation of B30-MDP in B30-MDP/cholesterol mixed vesicles was influenced by the particle size, but not by the fluidity of the membranes. In the case of B30-MDP/phospholipid mixed vesicles, MDP/phospholipid mixed vesicles, the degradation of B30-MDP was not influenced by either the membranes' fluidity or the particle size of the mixed vesicles.It is considered that the degradation of B30-MDP in the mixed vesicles is dependent on the membrane state, and the addition of cholesterol to B30-MDP vesicle inhibits the mutual interaction of MDP regions, whereas the addition of phospholipids hardly influences the mutual interaction of MDP regions, possibly owing to phase separation between B30-MDP and phospholipids. 相似文献
55.
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. |
56.
Yasuhiro Nakadaira Toshiaki Kobayashi Hideki Sakurai 《Journal of organometallic chemistry》1979,165(3):399-405
1,1,2,2-Dimethyl-3,6-diphenyl-1,2-disilacyclohexadiene reacts with iron pentacarbonyl or diiron nonacarbonyl to give the corresponding (diene)iron tricarbonyl complex which undergoes novel ring contraction reaction to (η4-1,1-dimethyl-2,5-diphenyl-1-silacyclopentadiene)iron tricarbonyl on thermolysis at 160°C. Similar results were observed with 1,1,2,2-tetramethyl-3,4,5,6-tetraphenyl-1,2-disilacyclohexadiene. 相似文献
57.
Copper(II) complex with
-piperidine-3-carboxylic acid (
-Hpipe-3):[Cu(
-pipe-3)2(H2O)] and cobalt(II) and nickel(II) complexes with piperidine-4-carboxylic acid (Hpipe-4):[M(Hpipe-4)2(H2O)4]Cl2 (M: Co, Ni) have been prepared and characterized by means of IR and powder diffuse reflection spectra, thermal analysis, and magnetic susceptibility. The crystal structures of these complexes have been determined by X-ray diffraction. The crystal of [Cu(
-pipe-3)2(H2O)] is orthorhombic with the space group Pbcn. The copper atom is in a square pyramidal geometry, ligated by two carboxylato oxygen atoms, two nitrogen atoms, and a water molecule. One molecule of this complex consists of either
-piperidine-3-carboxylic acid or
-piperidine-3-carboxylic acid. The crystals of [M(Hpipe-4)2(H2O)4]Cl2 are monoclinic with space group P21/n. In these complexes the metal atom is in an octahedral geometry ligated by two carboxylato oxygen atoms and four water molecules. 相似文献
58.
The authors have examined the tumor affinity of various 99mTc-labelled radiopharmaceuticals to Ehrlich's tumor for the purpose of delineating positively human malignant neoplasm. This paper includes biologic distributions of 99mTc-Sn-diphosphonate (99mTc-EHDP), 99mTc-Sn-dimercaptosuccinic acid (99mTc-DMSA) and 99mTc-Sn-diethyl stilbestrol diphosphate (99mTc-DSDP, 99mTc-Honvan) as the second report on the tumor affinity to the Ehrlich-bearing mice. (a) Tumor concentration of 99mTc-EHDP was lowest and the positive delineation of implanted tumor with 99mTc-EHDP was poorest in sequential images, though the active accumulation to some soft tissue maglinant neoplasms, the breast cancer and the thyroid cancer, has been reported. (b) Tumor concentration and tumor to blood ratio of 99mTc-DMSA were not so high on the contrary of our expectation that 197Hg-DMSA may show the high tumor concentration and the high tumor to blood ratio like 197Hg chlormerodrin as same renal scanning radiopharmaceuticals. (c) Tumor concentration of 99mTc-DSDP was highest. Tumor to blood concentration ratio, however, was lower than that of the above mentioned radiopharmaceuticals but tumor to liver ratio and/or tumor to lung ratio was over 1.0 at the earlier time. Biologic distribution of 99mTc-DSDP was similar to that of 32P labeled DSDP and then it is presumed that 99mTc is labeled at phosphate ester of DSDP which is dephospholytated immediately by phospholylase in vivo following the intravenous injection. Therefore, it may be assumed that the accumulation mechanism of 99mTc-DSDP to Ehrlich's tumor is related to the phospholylase activity in neoplasms but is not known precisely. 相似文献
59.
Hetero-biaryl compounds were prepared via the Suzuki-Miyaura coupling reaction of hetero-aryl moieties containing an unprotected NH2 group and arylboronic acids. D-t-BPF was found to be an efficient ligand for the cross-coupling of NH2-unprotected hetero-aryl chlorides with phenylboronic acid. 相似文献
60.
Highly fluorescent polymer particles were prepared with Eu beta-diketonates complex as a fluorophore by miniemulsion polymerization technique. Eu beta-diketonates complex has a long decay time, a large Stokes shift, and very narrow emission bands in comparison with other organic fluorescent compounds. Aqueous miniemulsion was prepared by mixing monomer, crosslinker, hydrophobe, and Eu beta-diketonates complex and then putting the mixture into an aqueous solution of surfactant, followed by ultrasonication. An aqueous solution of initiator was added to the miniemulsion to obtain fluorescent polymer particles, which were monodispersed without aggregation. Particle size was decreased to deca-nano scale by increasing the amount of surfactant. Fluorescent intensity was increased by using Eu beta-complex coordinated with additional ligand. Further fluorescence quantum yields and fluorescent properties in the presence of DNA were investigated to the confirm superiority of Eu beta-diketonates complexes in polymer particles. 相似文献