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71.
Abstract— Single-celled protonemata of Adiantum capillus-veneris were cultured under continuous red light for 6 days and then in the dark for 15 h. Brief local exposure of a flank (5 times 20 /mi) of the subapical region of a protonema to a microbeam of red light effectively induced a phototropic response toward the irradiated side. The degree of the response was dependent upon the fluence of the red light. Red/far-red reversibility was typically observed in this photoreaction, showing that phytochrome was the photo-receptive pigment. When the flank was irradiated with a microbeam of linearly polarized red and far-red light, red light with an electrical vector parallel to the cell surface was most effective. However, the far-red light effect was most prominent when its electrical vector was normal to the cell surface. These polarized light effects indicate the different dichroic orientation of Pr (red-light-absorbing form of phytochrome) and Pr (far-red-light-absorbing form of phytochrome) at the cell flank. 相似文献
72.
Furuya K. Munakata F. Matsuo K. Akimune Y. Ye J. Okada A. 《Journal of Thermal Analysis and Calorimetry》2002,69(3):873-879
An advanced silicon nitride material with high isotropic thermal conductivity (149 W m-1 K-1) has been developed. This high thermal conductivity was achieved with a process that combines high-quality seed crystals
with a suitable additive system to promote grain growth. In this process, the addition of β-Si3N4 seed crystals was found to be effective in improving thermal conductivity due to their low defect and impurity concentrations.
The seed crystals seem to work as nuclei for controlling grain growth during the sintering process. Controlling the growth
of elongated grains so that they do not interact with each other seems important for suppressing the generation of new defects
inside the grains.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
73.
74.
H. Yasuda K. Furuya 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2000,10(2):279-283
Alloying behavior and phase stability has been studied in situ by transmission electron microscopy using clusters in the Au-Sn system. When tin atoms are vapor-deposited onto nm-sized
gold clusters, rapid dissolution of tin atoms into gold clusters takes place and as a result Au-rich solid solution, amorphous-like
Au-Sn alloy and AuSn compound clusters are formed depending upon the concentration of tin. The remarkable enhancement of solubility
has been observed in Au-rich solid solution and AuSn compound. It becomes more difficult to form two phases in the interior
of individual clusters even if the composition of alloy clusters falls in the two-phase region in the phase diagram for the
bulk alloy and as a result amorphous-like phase is stabilized in nm-sized Au-Sn alloy clusters.
Received 2 August 1999 and Received in final form 8 November 1999 相似文献
75.
76.
In this paper we consider the asymptotic behaviour of the error term Q(x;h/q), which is defined by (1.2). In particular, we derive a certain lower bound estimate of this function when h, k and q are fixed integers, and study the non-trivial upper bound estimates of the mean value of Q(x;h/q). 相似文献
77.
T Nakajima Y Takashima A Furuya Y Ozawa Y Kawashima 《Chemical & pharmaceutical bulletin》1990,38(4):1027-1031
We prepared indomethacin (IM) sustained-release suppositories using sugar ester (SE) as an additive. The suppositories were prepared by the fusion method with IM, SE, and Witepsol H-15 (H-15) and their availabilities in vitro and in vivo were evaluated mainly by the drug release test and the absorption test in rabbits, respectively. The softening point of the suppositories increased with increasing SE content. In the release test with the Muranishi method, slow-release profiles were obtained when the SE content was more than 52.5%. The absorption of IM from these suppositories, however, was very little. In the other release test, e.g. immersion method with gauze, all of the suppositories with SE showed slow-release profiles, and the drug release rates clearly depended on the SE content. The drug was released from the suppositories by the following leaching-type mechanism proposed by Higuchi. The suppository with a 30% SE content showed a sustained-plasma level of IM, but the other suppositories did not. It was concluded that an appropriate content of SE (i.e. 30%) in the suppository base was required to obtain sustained-release because it reasonably regulated the infiltration of rectal fluid into the suppository and the mechanical strength of the suppository against disintegration. 相似文献
78.
Furuya H Nakao H Yamada I Ruan YF Yap YK Yoshimura M Mori Y Sasaki T 《Optics letters》2000,25(21):1588-1590
We developed a Gd(x)Y(1-x)Ca(4)O(BO(3))(3) (GdYCOB) crystal for control of optical birefringence. GdYCOB crystals were successfully used to generate noncritical phase-matched (NCPM) second and third harmonics of 1064-nm lights. However, we observed degradation of third-harmonic-generation (THG) output power and distortion of the beam pattern as a result of photoinduced damage and thermal dephasing. The photoinduced damage was classified into two types. One was gray-track and the other was photorefractive damage. It seems that these types of damage were similar to the types of damage that occurred with KTiOPO(4) and LiNbO(3) crystals. We tried to circumvent this problem by crystal heating. Photoinduced damage of GdYCOB was overcome by elevation of the crystal temperature, and NCPM THG (355-nm) output power from heated GdYCOB increased to 9 mW (62.5 kHz). 相似文献
79.
The structure of a new macrocyclic pyrrolizidine alkaloid, ligularidine(1), having significantly high mutagenic activity was elucidated and the configurations of the necic acid and its enantiomer reported by Edwards2 were also determined. 相似文献
80.
Experimental Mechanics - Cyclic strain at the tip zone of a fatigue crack could be measured continuously by the fine-grating method. At one cycle of fatigue, the loop between strain at the crack... 相似文献