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71.
Self-dual codes over exist for all even lengths. The smallest length for which the largest minimum weight among self-dual codes has not been determined
is 24, and the largest minimum weight is either 9 or 10. In this note, we show that there exists no self-dual [24, 12, 10]
code over , using the classification of 24-dimensional odd unimodular lattices due to Borcherds.
相似文献
72.
A new geranylated aromatic compound, 5-[(2'E)-3',7'-dimethyl-2',6'-octadienyl]-4-hydroxy-6-methoxy-1-isoindolinone (1), was isolated from the fruiting bodies of the mushroom Hericium erinaceum (Bull.: Fr.) Pers. (Hericiaceae) together with three known sterols, 5alpha,6alpha-epoxy-(22E)-ergosta-8(14),22-diene-3beta,7alpha-diol (2), (22E)-ergosta-7,9(11),22-triene-3beta,5alpha,6beta-triol (3) and (22E)-ergosta-7,22-diene-3beta,5alpha,6alpha,9alpha-tetrol (4). The structure of the new compound was elucidated on the basis of spectral data. 相似文献
73.
Hideo Inaba Fujio Komatsu Akihiko Horibe Naoto Haruki Akito Machida 《Heat and Mass Transfer》2008,44(11):1305-1313
This paper describes heat and mass transfer characteristics of organic sorbent coated on heat transfer surface of a fin-tube
heat exchanger. The experiments in which the moist air was passed into the heat exchanger coated with sorption material were
conducted under various conditions of air flow rate (0.5–1.0 m/s) and the temperature of brine (14–20°C) that was the heat
transfer fluid to cool the air flow in the dehumidifying process. It is found that the sorption rate of vapor is affected
by the air flow rate and the brine temperature. Meanwhile, the attempt of clarifying the sorption mechanism is also conducted.
Finally the average mass transfer coefficient of the organic sorbent coated on heat transfer surface of a fin-tube heat exchanger
is non-dimensionalzed as a function of Reynolds number and non-dimensional temperature, and it is found that the effect of
non-dimensional temperature on them is larger than Reynolds number . 相似文献
74.
Five new monoterpene glycosides, ovatolactone 7-O-(6'-O-p-hydroxybenzoyl)-beta-D-glucopyranoside, ovatic acid methyl ester 7-O-(6'-O-p-hydroxybenzoyl)-beta-D-glucopyranoside, 7-O-p-hydroxybenzoylovatol 1-O-(6'-O-p-hydroxybenzoyl)-beta-D-glucopyranoside, 6'-O-p-hydroxybenzoylcatalposide and (2E,6R)-2,6-dimethyl-8-hydroxy-2-octenoic acid 8-O-[6'-O-(E)-p-coumaroyl]-beta-D-glucopyranoside were isolated from the fallen leaves of Catalpa ovata G. Don. Their structures were determined by extensive spectroscopic studies and syntheses. 相似文献
75.
The use of dielectric barrier discharge (DBD) plasmas has become a practical way to carry out surface treatment where precise control of the plasma parameters, such as rotational and vibrational temperatures (Trot and Tvib), is required. As the Tvib of an atmospheric pressure plasma jet appears to be the most important parameter related to the improvement of surface treatments, in this work, we analysed two methods to increase the values of Tvib in a DBD plasma jet device. One of the methods is to reduce the exit size (ø) of the DBD reactor, which results in an increase in the measured Tvib values, due to an increase in the pressure inside the reactor. The other method is to change the gas flow rate (GFR) used to produce the plasma jets. This leads to a Tvib reduction when the GFR is increased in the case of using helium or nitrogen as the working gas, but the opposite happens (an increase in the Tvib values) when argon is used, with different phenomena causing the variation of Tvib in each situation. 相似文献
76.
77.
On irradiation arylcarbothioamides (1) undergo, in the absence of oxygen, the Paterno-Büchi reaction with olefins followed by cleavage, whereas under aerobic conditions the photoreaction proceeds to give 4 and 5 probably via nitrile sulfide intermediates. 相似文献
78.
Shigeyuki Tasaka Hirokazu Tanabe Yoshiyuki Sasaki Toshiki Machida Mayumi Iino Akira Kiue Seiji Naito Michihiko Kuwano 《Journal of heterocyclic chemistry》1997,34(6):1763-1767
We have investigated 3-substituted-2-phenylimidazo[2,1-b]benzothiazole derivatives and herein we have discussed their pharmaceutical activities. We found that some 2-phenyl-5,6,7,8-tetrahydroimidazo[2,1-b]-benzothiazoles could overcome multidrug resistance for tumor cells. Among them, 2-phenyl-3-(N-methyl-3-piperidyl)carbonylammomiinomemyl-5,6,7,8-tetrahydVoimidazo[2,1-b]benzothiazole [N276-12] demonstrated the most potent activity for overcoming multidrug resistance. 相似文献
79.
We study the role of surface modes in the process of vortex formation in harmonically trapped BEC. It is shown that the vortex nucleation and penetration to the inner part of the cloud occur at velocities slightly exceeding the surface mode critical velocity. Surface modes induce ripples of the order parameter; these ripples are then transformed into vortex-antivortex pairs. After this, vortices move to the inner part of the cloud, whereas antivortices go in the opposite direction 相似文献
80.