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101.
We synthesized some 4,4'- and 2,2'-dihydroxytriphenylmethane derivatives 3a--e and 4a--c by condensation of phenol 1 and aromatic aldehyde 2 in moderate to good yields (30--83%). Most of them showed significant antiviral activity against herpes simplex virus type 1 (anti-HSV-1 activity) in a plaque reduction assay. The most potent antiviral activity (EC(50)=0.79 microg/ml) was observed in the 4,4'-dihydroxytriphenylmethane derivative 3b. This compound 3b showed lower cytotoxicity (CC(50)=30.2 microg/ml), compared to that of the prototype 3a.  相似文献   
102.
It is shown that in phase-pinned charge-density-wave condensates an external electric field induces thermally activated continuous creation of new domains, when the pinning potential is periodic in the phase π of the condensate wave function. The mechanism gives rise to a nonlinear dc conductivity at finite temperatures, which seems to account for the anomalous conductivity observed in NbSe3.  相似文献   
103.
104.
We present calculations for the influence of fluctuations in high field superconductors where the critical field is limited by Pauli paramagnetism. Due to the fact that the critical field at the second order phase transition point as function of temperature may have a maximum atT≠0 the additional conductivity due to fluctuations may have a nonmonotonic temperature dependence. This way we can account for recent experimental findings by Tedrow, Meservey and Schwartz. We also calculate the additional tunneling density of states due to fluctuations. Under proper conditions it exhibits a maximum at zero frequency like in the gapless regime. Finally we show that our findings of a nonmonotonic resistivity should also apply to superconductors containing magnetic impurities such as La3-x Gd x In in an external field.  相似文献   
105.
IntroductionThe photo-and thermo-chromisms of organometallic compounds have been intensivelystudied during thelast1 0 years.Meriwetheretal.[1 ,2 ] examined the chromic behaviorofmet-al-dithizone(phenyldiazenecarbothionic acid2 -phenylhydrazide) complexesin detail.From thekinetic and infrared studies,they showed thatthe central metal of a dithizonate complex de-termined the photochemical stability,the rate of the thermal return reaction,and the colorofthe dithizonate complex.As reported by Mer…  相似文献   
106.
This paper considers the oblique propagation of a plane SH-wave in an inhomogeneous elastic medium whose material properties vary harmonically with a space variable. Assuming a small deviation in the harmonic variation, the method of multiple scales is applied and approximate solutions are obtained for three types of the medium.Effects of oblique propagation of SH-waves on a resonant frequency and on an unstable region of wave propagation are discussed. Effects on the reflection coefficient at a stress-free boundary when the wave propagates in a semi-infinite space are also discussed.  相似文献   
107.
We describe in this study the asymmetric synthesis of radioisotope (RI)-labeled selective glucocorticoid receptor modulator. This synthesis is based on optimization of the cinchona alkaloid catalyzed addition of 6-bromoindole to ethyl trifluoropyruvate and Negishi coupling of zinc cyanide to the 6-bromoindole moiety. [1?C] Labeled (-)-{4-[(1-{2-[6-cyano-1-(cyclohexylmethyl)-1H-indol-3-yl]-3,3,3-trifluoro-2-hydroxypropyl}piperidin-4-yl)oxy]-3-methoxyphenyl}acetic acid (-)-1 was synthesized successfully with high enantioselectivity (>99% ee) and sufficient radiochemical purity.  相似文献   
108.
The effect of the surface layering time of lactose carrier particles on the dry powder inhalation properties of salbutamol sulfate was investigated. Lactose carrier particles were layered with vegetable magnesium stearate by physical mixing. In the present study, drug/carrier powder mixtures were designed consisting of micronized salbutamol sulfate and lactose carriers with various particle surface conditions prepared by surface layering. These powder mixtures were aerosolized by a Jethaler, and the in vitro deposition properties of salbutamol sulfate were evaluated by a twin impinger. Compared with the powder mixed with unlayered lactose carrier, the in vitro inhalation properties of the powder mixture prepared using the surface layering lactose carrier were significantly different, showing that the in vitro inhalation properties of the drug/carrier powder mixtures were improved. In vitro deposition properties (RP) increased with surface layering time. Using this surface layering system would thus be valuable for increasing the inhalation properties of dry powder inhalation.  相似文献   
109.
The electronic contribution to the thermal conductivity in a pure type II superconductor in a field immediately belowH e2 is reconsidered. In a pure type II superconductor the electron scattering due to the electron-phonon interaction becomes of importance. The inclusion of the electron-phonon interaction into the theory gives rise to a sharper drop of the thermal conductivity in a field slightly belowH e2. Also the problem of the diamagnetization factor is discussed.  相似文献   
110.
The Stroh formalism is a powerful and elegant mathematical method developed for the analysis of the equations of anisotropic elasticity. The purpose of this exposition is to introduce the essence of this formalism and demonstrate its effectiveness in both static and dynamic elasticity. The equations of elasticity are complicated, because they constitute a system and, particularly for the anisotropic cases, inherit many parameters from the elasticity tensor. The Stroh formalism reveals simple structures hidden in the equations of anisotropic elasticity and provides a systematic approach to these equations. This exposition is divided into three chapters. Chapter 1 gives a succinct introduction to the Stroh formalism so that the reader could grasp the essentials as quickly as possible. In Chapter 2 several important topics in static elasticity, which include fundamental solutions, piezoelectricity, and inverse boundary value problems, are studied on the basis of the Stroh formalism. Chapter 3 is devoted to Rayleigh waves, for long a topic of utmost importance in nondestructive evaluation, seismology, and materials science. There we discuss existence, uniqueness, phase velocity, polarization, and perturbation of Rayleigh waves through the Stroh formalism.

The Table of Contents and Index are also provided as Electronic Supplementary Material for online readers at doi:   相似文献   
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