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131.
The diagonal viewing angle light leakage in a black state of in-plane switching (IPS) liquid crystal display (LCD) associated with pretilt angle has been investigated. The mechanical rubbing process with a cloth causes relatively high pretilt angle in the homogenously aligned liquid crystals (LCs) so that the tilted LC director results in increase of a light leakage in a black state at diagonal viewing angles. In this study, we theoretically estimated using classical optic theory how the light leakage in a black state at diagonal viewing angle is associated with the pretilt angle and also proposed an effective method to reduce the pretilt angle from 1.5° to 0° in rubbed IPS LCD by utilising polymer stabilisation. With this approach, we could successfully acquire a better black quality in all viewing angles as compared with normal IPS LCD. 相似文献
132.
On the setting of the half-space we introduce the Schatten-Herz classes of Toeplitz operators and obtain characterizations
for positive Toeplitz operators to belong to those classes. We also prove results concerning the boundedness and compactness
of Toeplitz operators with Herz symbols. Such a study has been recently done on the ball. At a critical step of the proofs
we employ a much simplified argument to extend the range of parameters for Herz spaces on which the Berezin transform is bounded.
Our results show not only that most of results on the ball continue to hold, but also that there is some pathology caused
by the unboundedness of the domain.
The first author was in part supported by a Korea University Grant(2007), the second author was in part supported by Hanshin
University Research Grant, and both authors were in part supported by KOSEF(R01-2003-000-10243-0). 相似文献
133.
Mariem Saada Hanen Wasli Ins Jallali Rim Kboubi Karl Girard-Lalancette Vakhtang Mshvildadze Riadh Ksouri Jean Legault Susana M. Cardoso 《Molecules (Basel, Switzerland)》2021,26(19)
The fractionation of the methanolic extract (MeOH-E) of Retama raetam (Forssk.) Webb & Berthel and further analysis by thin layer chromatography resulted in four fractions (F1, F2, F3 and F4) that, in parallel with the MeOH-E, were screened for antioxidant, cytotoxic, antidiabetic and antibacterial properties. In addition, chemical characterization of their bioactive molecules was performed using LC-DAD-ESI/MSn. The results indicated that F3 was the most promising regarding antioxidant and cytotoxicity abilities, possibly due to its richness in flavonoids class, particularly isoflavones. In turn, F1 was characterized by the presence of the most polar compounds from MeOH-E (organic acids and piscidic acid) and showed promising abilities to inhibit α-amylase, while F4, which contained prenylated flavonoids and furanoflavonoids, was the most active against the tested bacteria. The gathered results emphasize the distinct biological potentials of purified fractions of Retama raetam. 相似文献
134.
Rim G.-H. Lee H.-S. Pavlov E.P. Kim G.-H. Cho C.-H. Choi Y.-W. Kim J.-S. 《IEEE transactions on plasma science. IEEE Nuclear and Plasma Sciences Society》2000,28(5):1362-1367
Many pulsed power applications require short high-voltage pulses with a high-repetition rate. Conventional high-voltage discharge pulse-switches such as thyratrons, spark gap switches, and vacuum tube switches have a short lifetime, whereas the semiconductor switches have a long lifetime and high reliability. The semiconductor switches, however cannot be directly applied to fast high-voltage pulsed power generation due to their limited operating voltage ratings despite their relatively long switching times. Therefore, they are used with voltage amplification and a pulse compression stage. This paper describes two pulse generators that use the semi-conductor switches and nonlinear capacitors: one is based on an opening switch (IGBT) and inductive energy storage, the other is a combination of a closing switch (RSD) and capacitive energy storage 相似文献
135.
On the setting of the half-spaceR
n–1×R
+, we investigate Gleason's problem for harmonic Bergman and Bloch functions. We prove that Gleason's problem for the harmonicL
p
-Bergman space is solvable if and only ifp>n. We also prove that Gleason's problem for the harmonic (little) Bloch space is solvable. 相似文献
136.
137.
Mathematical Physics, Analysis and Geometry - In the 1977 paper of McCoy et al. (J. Math. Phys. 18, 1058–1092, 1977) it was shown that the limiting two-point correlation function in the... 相似文献
138.
Young Hoon Lee Mihyun Kim A Rim Woo Ji Young Choi Jong Chul Byun Jack M. Harrowfield Woo Taik Lim Pierre Thu��ry Yang Kim 《Journal of inclusion phenomena and macrocyclic chemistry》2011,71(3-4):395-407
Structural studies of seven complexes of ligands derived from various azetidine- and oxetane-containing ligands characterise the difference in reactivity of both free and bound forms of these two four-membered heterocycles. The relatively unreactive azetidine ring is preserved in a variety of transformations, whereas facile opening of the oxetane ring provides a convenient pathway to complexes with pendent functionality. 相似文献
139.
140.