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1.
The running coupling and the Kugo-Ojima parameter of unquenched lattice Landau gauge are simulated and compared with the continuum
theory. Although the running coupling measured by the ghost and gluon dressing function is infrared suppressed, the running
coupling has a maximum of α0 ∼ 2 − 2.5 at around q = 0.5 GeV irrespective of the fermion actions (Wilson fermions and Kogut-Susskind (KS) fermions). The Kugo-Ojima parameter
c which saturated to about 0.8 in quenched simulations becomes consistent with 1 in the MILC configurations produced with the
use of the Asqtad action, after averaging the dependence on polarization directions caused by the asymmetry of the lattice.
The presence of the correction factor 1 + c
1/q
2 in the running coupling depends on the lattice size and the sea quark mass. In the large lattice size and small sea quark
mass, c
1 is confirmed of the order of a few GeV. The MILC configuration of a = 0.09 fm suggests also the presence of dimension-4 condensates with a sign opposite to the dimension-2 condensates. The
gluon propagator, the ghost propagator, and the running coupling are compared with recent pQCD results including an anomalous
dimension of fields up to the four-loop level. 相似文献
2.
A simple method to label oligosaccharides with a multifunctional fluorescent group was developed. Oligosaccharides were quantitatively labeled at their reducing termini with pyrene butanoic acid hydrazide. The pyrene-labeled oligosaccharides were successfully applied to fluorescence polarization measurements and ELISA at picomole quantity, which was not previously reached by other procedures. This labeling method should prove to be useful in a variety of aspects in glycobiology. 相似文献
3.
4.
A poly(N-isopropylacrylamide) (PNIPAAm)-like biodegradable thermosensitive polydepsipeptide, poly[Glc-Asn(N-isopropyl)], was synthesized by introducing an isopropyl amide group into poly[Glc-Asn]. Poly[Glc-Asn(N-isopropyl)] was degraded in vitro by cleavage of the ester bonds in the main chain in water at room temperature. The non-toxic nature of the polymer and its degradation products, coupled with a cloud point at 29 degrees C in water, make this polymer attractive for biomedical implant applications. 相似文献
5.
Tatsuro Ouchi Hirotoshi Fujie Satoshi Jokei Yoshiomi Sakamoto Hidenori Chikashita Takeshi Inoi Otto Vogl 《Journal of polymer science. Part A, Polymer chemistry》1986,24(9):2059-2074
Acryloyl-type polymer fixing 1-β-carbonylethyl-5-fluorouracil residues through D -glucofuranoses via ester bonds was synthesized by means of polymerization of the corresponding monomer and polymer reaction. In order to provide the water-soluble objective polymer, the copolymerization of the acryloyl-type monomer with acrylamide was carried out. The extent of release of 5-FU residues from the copolymer was investigated in the enzyme or nonenzyme system in vitro. Furthermore, the antitumor activities of the water-insoluble homopolymer and water-soluble copolymer obtained were tested in vivo. 相似文献
6.
Tatsuro Ouchi Tamio Nishimura Minoru Imoto 《Journal of polymer science. Part A, Polymer chemistry》1976,14(11):2695-2702
It was found recently that the system of nylon 3, copper(II) ion, and water could initiate a radical polymerization of methyl methacrylate(MMA). In the present paper, the effect of average chain length of the molecules of nylon 3 on the rate of polymerization of MMA was studied. The rate increased with the chain length of nylon 3. This result was explained well by the fact that the shorter nylon 3 forms a complex with copper (II) ion more easily than longer nylon 3. It was assumed that the shorter nylon 3 fills three or four coordination sites of copper(II) ion and loses the ability to initiate the polymerization. The efficiency of grafting of MMA and the degree of polymerization of MMA homopolymer were independent of the chain length of nylon 3. 相似文献
7.
An enantiospecific coupling of propargylic esters and carbonates with arylboronic acids has been developed using a palladium catalyst. Optically active 1,3-disubstituted allenes were synthesized with high enantiomeric excesses by carrying out the reactions under basic aqueous conditions. 相似文献
8.
Tatsuro Gueshi Koichi Tokuda Hiroaki Matsuda 《Journal of Electroanalytical Chemistry》1978,89(2):247-260
Equations for chronopotentiometry and chronoamperometry at partially covered electrodes have been derived using a model of hexagonal array of cylidrical spaces terminated, at the electrode surface, by concentric active and inactive regions. The boundary value problem was shown to be analogous to that for a charge transfer preceded by a chemical reaction. Experiments with the reduction of ferricyanide on gold model electrodes partially covered with photoresist layer showed excellent agreement with the theory. Application of the equations to estimation of coverage and size of active sites distributed on a electrode surface is discussed. 相似文献
9.
Jin-Ming Lin Tatsuro Nakagama Hitoshi Okazawa Xing-Zheng Wu Toshiyuki Hobo 《Fresenius' Journal of Analytical Chemistry》1996,354(4):451-454
Capillary gel electrophoresis (CGE) was successfully applied to the separation of optically active isomers and position isomers by incorporating a suitable cyclodextrin chiral selector in polyacrylamide gel. A commercially available ß-cyclodextrin (ß-CD) was used for enantioselectivity towards o-, m- and p-nitrobenzoic acid, o-, m- and p-hydroxybenzoic acid, o-, m- and p-toluic acid and the optical isomers of dansyl-D,L-leucine and R,S-1,1-binaphthyl-2,2-dihydrogenphosphate. Especially the effect of organic solvents, such as acetonitrile, methanol, dimethylsulphoxide and others were examined in detail. The resolution varied to some extent with the addition of the organic solvent to the polyacrylamide gel and the running buffer solution. The possible mechanism has also been discussed. In addition, quantitative aspects of the separation of stereoisomers using CGE have been studied, showing that both the resolution and accuracy of the determinations were affected by the ratio of the enantiomers. 相似文献
10.
S. Furui 《Zeitschrift fur Physik C Particles and Fields》1995,68(4):661-671
Experimental data of $\bar pp$ annihilation into 3π0 and π+π0π? are analyzed in the quark pair creation model (3 P 0 Model) with planar quark diagram topology. There are two form factors depending on whether 1) the two π′s contain a quark or an antiquark that originates from ap or a $\bar p$ respectively, or 2) one π contain a quark and an anti-quark both created from the vacuum. We call the amplitude of the first as a G-type and the latter as the an F-type. The intermediate states in G-type processes which contain correlations of the3 P 0 vertices in the initial state and those in the final state can be regarded as gluons of 0++ and a $\bar qq$ . The two π resonance like structure of 0++ (1520) observed in 3π0 and 2++ observed in π+π0π? can be interpreted as the interference of the G-type amplitudes with the F-type amplitudes. 相似文献