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311.
312.
Natsuhiro Azuma Kiyoshi Kitahara Takashi Motoi Sumio Tokita Hisao Nishi 《Journal of heterocyclic chemistry》1993,30(1):225-227
1,4,8,11,15,18,22,25-Octaalkoxy-2,3,9,10,16,17,23,24-octakis(phenylthio)phthalocyaninato copper(II) was synthesized. They were easily soluble in organic solvents and their Q-bands showed bathochromic shifts about 100 nm compared with unsubstituted phthalocyaninato copper(II). Their properties were examined. 相似文献
313.
The photodissociation dynamics of organometallic compounds (tetramethyltin, trimethylgallium, trimethylindium and dimethylzinc) adsorbed on a quartz substrate at 100 K have been studied by time-of-flight mass spectrometry, detecting mainly CH3 photofragments. Shapes of the time-of-flight spectra depend on the flux of the dissociation laser at 193 nm and the thickness of multilayers of organometallic compounds. In thick layers, not only a low energy component but also a high energy component are observed in the time-of-flight spectrum of the CH3 photofragments. In thin layers, relaxation processes take place so quickly that the product time-of-flight profiles are characterized by a Maxwell–Boltzmann temperature profile. 相似文献
314.
Haruko Okamura 《Graphs and Combinatorics》1987,3(1):159-189
Suppose thatk ≥ 1 is an odd integer, (s 1,t 1),..., (s k> ,t k ) are pairs of vertices of a graphG andλ(s i ,t i ) is the maximal number of edge-disjoint paths betweens i andt i . We prove that ifλ(s i ,t i )≥ k (1≤ i ≤ k) and |{s 1,...s k ,t 1,...,t k }| ≤ 6, then there exist edge-disjoint pathsP 1,...,P k such thatP i has endss i andt i (1≤ i ≤ k). 相似文献
315.
Masateru Ono Shin Yasuda Kaori Nishi Kazutaka Yamamoto Satoshi Fuchizaki Satomi Higuchi 《Natural product research》2016,30(8):904-911
Two new ursane-type triterpenoids (1, 2) attached to isopropylidenedioxy group were isolated from the seeds of blackberry (Rubus fructicosus L., Rosaceae) along with two known ursane-type triterpenoids, 2,3-O-isopropylidenyl-2α,3α,19α-trihydroxyurs-12-en-28-oic acid (3) and 1β-hydroxyeuscaphic acid (4). The chemical structures of 1 and 2 were determined to be 2,3-O-isopropylidene-1β,2β,3β,19α-tetrahydroxyurs-12-en-28-oic acid and 1,2-O-isopropylidene-1β,2α,3α,19α-tetrahydroxyurs-12-en-28-oic acid, respectively, based on spectroscopic data. Additionally, their cytotoxic activity towards HL-60 human leukaemia cells was evaluated. Among them, 3 demonstrated a clear cytotoxic activity with 72.8 μM of IC50 value. 相似文献
316.
Yasuo Horiuchi Yoshio Nishi Noburu Sokabe Akira Murai 《International Journal of Infrared and Millimeter Waves》1985,6(9):929-946
Sixty and three absorption transitions in D2CO and H2CO, respectively, have produced a number of far infrared laser lines when they are pumped by an etalon-tuned TE-CO2 laser. Almost all the absorption transitions pumped previously by a free runing TE-CO2 laser have been efficiently pumped by the etalon tuned CO2 laser and found to have offset within ±500 MHz from the line-center of the relevant CO2 pump lines. 22 (1) absorption and 63 (4) emission lines of D2CO (H2CO) are assigned. Some of these lines have generated superfluorescence. In paticular, the D2CO 319-m line pumped by CO2-9P(32) delivered an output energy of approximately one half that of the well-known D2O 66-m. It is shown that a large electric dipole moment and an appreciable amount of fractional population in the lower level of the pump transition of this line are responsible to the superfluorescence. 相似文献
317.
In this study, nano-sized bacterial magnetic particles (BMPs) displaying human estrogen receptor ligand binding domain (ERLBD) on the surface was successfully produced by the magnetic bacterium, Magnetospirillum magneticum AMB-1. Furthermore, a non-isotopic binding assay for estrogenic compounds using the BMPs displaying ERLBD was developed. A BMP membrane-specific protein, Mms16, was used as an anchor molecule to localize ERLBD on the surface of BMPs. ERLBD-BMP complexes were simply extracted by magnetic separation from ruptured AMB-1 transformants and used for the assay based on the competitive binding of alkaline phosphatase conjugated 17β-estradiol (ALP-E2) as a tracer. Dissociation constant of the receptor was 2.3 nM. Inhibition curves were evaluated by the decrease in luminescence intensity resulting from the enzymatic reaction of alkaline phosphatase. The overall simplicity of this receptor binding assay results in a method that can be easily adapted to a high throughput format. Moreover, this method can be integrated into a fully-automated ligand screening system using magnetic separation. 相似文献
318.
Electrokinetic chromatography is a new type of analytical separation method which belongs to the group of high performance capillary electrophoretic techniques but whose separation principle is based on that of chromatography. The solute distributes itself between a carrier and the surrounding medium. The carrier, which corresponds to the stationary phase in conventional chromatography, can be transported by electrophoresis with a different velocity from the surrounding medium. The separation is achieved by the differential solute distribution and the differential migration of the carrier. The charged molecules or charged molecular aggregates are employed as the carrier. Various kinds of carriers are available for electrokinetic chromatography along with different partition mechanisms. Among them, micellar electrokinetic chromatography, which employs an ionic micelle as a carrier, has become the most popular method because of its unique and attractive characteristics as well as the separating capability of electrically neutral or nonionic solutes in comparison with capillary zone electrophoresis. The present paper describes the principle, separation characteristics and its application to the analysis of pharmaceuticals. 相似文献
319.
Enantioselectivities observed in high-performance liquid chromatography (HPLC) with the novel chiral stationary phase (CSP-18C6I) derived from (+)-18-crown-6 tetracarboxylic acid (18C6H4) were investigated by using nuclear magnetic resonance (NMR) spectrometry. The elution orders in CSP-18C6I, that is, the S-enantiomer of 1-(1-naphthyl)ethylamine (1-NEA) and the -enantiomer (S-form) of alanine-β-naphthylamide (Ala-β-NA) eluted prior to each corresponding enantiomer, were successfully explained on the basis of the apparent binding constants (Ka) of the enantiomers to the CSP moiety which were calculated from 1H-NMR experiments. Detailed HPLC and NMR studies for the chiral recognition of racemic amino compounds with 18C6H4 hosts showed that 1H-NMR spectrometry is a useful technique for the investigation of the chiral recognition mechanism in HPLC. Additionally, it was found 18C6H4 can be recommended as a useful chiral shift reagent for the enantiomeric excess determination by 1H-NMR. 相似文献
320.