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121.
Jnn'ichi Toei Keizen Fujii Nobuyuki Baba 《Fresenius' Journal of Analytical Chemistry》1989,334(1):13-15
Summary A new type reaction valve for flow injection analysis has been developed. In a FIA system with this valve the injected sample is once passed into a loop of the valve, thereafter the valve is rotated to the next position. Therefore, the sample is retained in the loop in a stop-state for a long time and the next sample is introduced into another loop in the next position. When the valve is rotated for one round, the stopped sample in the fist loop is again passed into the detector flow cell. Thus, an analysis, which needs a long reaction time, can be performed with this valve with high precision.
Verbessertes Reaktionsventil für die Flie\injektionsanalyse相似文献
122.
We introduce the notions of approximate innerness and central triviality for endomorphisms on separable von Neumann factors, and we characterize them for hyperfinite factors by Connes-Takesaki modules of endomorphisms and modular endomorphisms which are introduced by Izumi. Our result is a generalization of the corresponding result obtained by Kawahigashi-Sutherland-Takesaki in automorphism case. 相似文献
123.
Hiroyuki Suga Satoshi Higuchi Daisuke Ishimoto Yuta Hashimoto Teruko Tsuchida Toshihide Baba 《Tetrahedron》2010,66(16):3070-6287
High enantioselectivities (94-96% ee) were obtained for the inverse electron-demand 1,3-dipolar cycloadditions between cyclohexyl vinyl ether and 2-benzopyrylium-4-olate generated via Rh2(OAc)4-catalyzed decomposition of o-methoxycarbonyl-α-diazoacetophenone. The reactions were effectively catalyzed by Eu(OTf)3, Ho(OTf)3, or Gd(OTf)3 complexes (10 mol %) of chiral 2,6-bis[(4S,5S)-4,5-diphenyl-2-oxazolinyl]pyridine. The reactions with the other electron-rich dipolarophiles such as allyl alcohol, 2,3-dihydrofuran, and butyl-tert-butyldimethylsilylketene acetal showed moderate enanantioselectivities (60-73% ee). Good to high enantioselectivities (73-97% ee) were also obtained for the cycloadditions between 3-acyl-2-benzopyrylium-4-olates, generated from methyl 2-(2-diazo-1,3-dioxoalkyl)benzoates and butyl or cyclohexyl vinyl ethers, in the presence of binaphthyldiimine (BINIM)-Ni(II) complexes (10 mol %). Under similar conditions, the reaction between methyl 2-(2-diazo-1,3-dioxohexyl)benzoate and 2,3-dihydrofuran was highly endo-selective, and moderately enantioselective (70% ee). For the BINIM-Ni(II)-catalyzed reactions of cyclohexyl vinyl ether, the use of an epoxyindanone as the 3-acyl-2-benzopyrylium-4-olate precursor revealed that the chiral Lewis acid can function as a catalyst for asymmetric induction. The scope of the cyclic carbonyl ylides was extended to those generated from 1-diazo-2,5-pentanedione derivatives, which were reacted with butyl or TBS vinyl ether and catalyzed using the (4S,5S)-Pybox-4,5-Ph2-Lu(OTf)3 complex to give good levels of asymmetric inductions (75-84% ee). 相似文献
124.
Haruka Baba 《Tetrahedron letters》2010,51(15):2063-4307
Treatment of alkylbenzenes with p-toluenesulfonamide and 1,3-diiodo-5,5-dimethylhydantoin (DIH) in a small amount of carbon tetrachloride at 60 °C gave the corresponding α-p-toluenesulfonylamido)alkylbenzenes in good to moderate yields. The present reaction is a simple method for the α-sulfonylamidation of the benzylic position in alkylbenzenes. 相似文献
125.
The electroreductive intramolecular coupling of aliphatic cyclic imides with ketones in isopropanol gave five- and six-membered cyclized products. Similarly, the electroreductive intramolecular coupling of aliphatic cyclic imides with O-methyloximes afforded five-, six-, and seven-membered cyclized products. These reactions provide a useful method to synthesize azabicyclo[n.m.0] compounds. The bicyclic products were stereoselectively transformed to the corresponding deoxylated compounds by reduction with NaB(CN)H3 or Et3SiH/BF3·Et2O. 相似文献
126.
Plínio C. Sathler Charles S. Craik Toshihiko Takeuchi Russolina B. Zingali Helena C. Castro 《Applied biochemistry and biotechnology》2010,160(8):2355-2365
Ecotin is a bidentate, fold-specific inhibitor of mammalian serine-proteases produced by Escherichia coli. This molecule may be engineered to increase and/or change its affinity and specificity providing significant biotechnological
potential. Since ecotin binds tightly to serine proteases of the trypsin fold, it may help to identify the role of these enzymes
in different biological processes. In this work, we tested ecotin variants as an affinity purification reagent for identifying
enzymes in samples of tumor progression and mammary gland involution. Initially, we used a commercial source of urokinase-type
plasminogen activator (u-PA) that remained fully active after elution from an affinity column of the ecotin variant (M84R,
M85R). We then successfully identified u-PA from more complex mixtures including lysates from a prostate cancer cell line
and involuting mouse mammary glands. Interestingly, a membrane-type serine protease 1 was isolated from the Triton X-100-solubilized
PC-3 cell lysates, and surprisingly, haptoglobin, a serine-protease homolog protein, was also identified in mammary gland
lysates and in blood. Haptoglobin does not prevent ecotin inhibition of u-PA, but it may act as a carrier within blood when
ecotin is used in vivo. Finally, this affinity purification matrix was also able to identify a thrombin-like enzyme from snake venom using an ecotin
variant directed against thrombin. Overall, the ecotin variants acted as robust tools for the isolation and characterization
of proteins with a trypsin fold. Thus, they may assist in the understanding of the role of these serine proteases and homologous
proteins in different biological processes. 相似文献
127.
Tsutom Hasuikea Toshihiko Hattori Toshio Hayashi Seiichi Wakaizumi 《Zeitschrift fur Physik C Particles and Fields》1997,76(1):127-132
Due to the large mass of top quark, CP violation in the top-quark decay is sensitive to the interactions mediated by Higgs bosons. We consider CP violation in t → W + b decay by calculating consistently in unitary gauge the CP-violating up-down asymmetry of the leptons from W boson decays in t → W + b, defined by Grz?dkowski and Gunion, in the two-Higgs doublet model with CP-violating neutral sector. The asymmetry is shown to be at most of the order of (1–4) × 10-4 for tan β = 1.0, where tan β is the ratio of vacuum expectation values for the two neutral Higgs bosons. 相似文献
128.
Akio Nara Nobuko Kobayashi Kazuko Hasegawa Katsuko Honba Shigeo Baba 《Microchemical Journal》1975,20(4):440-448
For the conductometric titration of fluoride with calcium acetate, solvent system in sample solution and titrant, concentration, and acidity of sample solution were examined to establish the titration conditions. Results of these examinations were transferred to the microdetermination of fluorine in organic compounds using oxygen flask combustion method.Comparative examination between quartz and Pyrex flasks for the combustion of fluorine samples indicated that good results were obtained by the use of the former flask, whereas the use of the latter one gave negative values of 1.0–1.6% due to the formation of boron fluoride during the combustion. 相似文献
129.
Tsutomu Asano Shota Sano Toshihiko Okabe Takumi Sano Chie Sawatari 《Journal of Macromolecular Science: Physics》2018,57(5):317-332
Using a modified method developed from Vonk's method, detailed values of crystallinity and crystal disorder were obtained by wide angle X-ray diffraction (WAXD). In Vonk's method, the crystallinity (w) is determined by extrapolation of the WAXD experimental curve back to zero scattering angle, while the distortion factor (k) is determined by the inclination of the experimental curve at zero scattering angle. In our new method, both w and k are determined at the same time by using the least squares method. In order to show the efficiency of our method, the new fitting procedure was applied to the experimental values of polyethylene and polyethylene terephthalate as measured by Vonk, and the values of w and k determined by our new method were compared with those found by Vonk's method. The new fitting method has the advantage that it uses the whole experimental curve. Moreover, our modified Vonk's method enables us to discuss crystal distortions as arising from first-kind (thermal) disorder and second-kind (paracrystalline) disorder. 相似文献
130.
Devi Ritu Singh Jaydip Potukuchi Baba 《International Journal of Theoretical Physics》2022,61(10):1-14
International Journal of Theoretical Physics - We successfully realized symmetric and asymmetric cyclic quantum teleportation by using different controllers for each receiver. In this study, Alice... 相似文献