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141.
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
142.
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
143.
Miwako Mori Katsutoshi Hori Masaya Akashi Masanori Hori Yoshihiro Sato Mayumi Nishida 《Angewandte Chemie (International ed. in English)》1998,37(5):636-637
Dry air is the source of molecular nitrogen for reactions with TiL4, Li, and TMSCl (L = Cl, OiPr; TMS = trimethylsilyl). The nitrogen–titanium complexes thus prepared can be used to synthesize indoles, pyrroles, and lactams from carbonyl compounds. Applying this method to 1 provides access to 2 , the key compound in the synthesis of (±)-lycopodine. 相似文献
144.
Norihiro Yamada Mayumi Iijima Kulthida Vongbupnimit Keiichi Noguchi Kenji Okuyama 《Angewandte Chemie (International ed. in English)》1999,38(7):916-918
A parallel rather than a perpendicular alignment of aromatic compounds with respect to surfactant molecules (see schematic representation) is preferred for the formation of a liposome structure, because the perpendicular alignment would reduce the hydrophilicity of the aggregate. This is the result of studies on crystalline complexes of monoalkylammonium halides and various aromatic compounds. 相似文献
145.
146.
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
147.
148.
Yuichi Michikawa Kentaro Fujimoto Kenji Kinoshita Seiko Kawai Keisuke Sugahara Tomo Suga Yoshimi Otsuka Kazuhiko Fujiwara Mayumi Iwakawa Takashi Imai 《Analytical sciences》2006,22(12):1537-1545
In the present work, a convenient microarray SNP typing system has been developed using a plastic base that covalently immobilizes amino-modified oligonucleotides. Reliable SNP allele discrimination was achieved by using allelic specificity-enhanced enzymatic extension of immobilized oligonucleotide primer, with a locked nucleic acid (LNA) modification at the SNP-discriminating 3'-end nucleotide. Incorporation of multiple biotin-dUTP molecules during primer extension, followed by binding of alkaline phosphatase-conjugated streptavidin, allowed optical detection of the genotyping results through precipitation of colored alkaline phosphatase substrates onto the surface of the plastic base. Notably, rapid primer extension was demonstrated without a preliminary annealing step of double-stranded template DNA, allowing overall processes to be performed within a couple of hours. Simultaneous evaluation of three SNPs in the genes TGFB1, SOD2 and APEX1, previously investigated for association with radiation sensitivity, in 25 individuals has shown perfect assignment with data obtained by another established technique (MassARRAY system). 相似文献
149.
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
150.
Aromatic C-H borylation using [IrCl(COD)]2 and 2,2′-bipyridinedicarboxylic acids was studied. 2,2′-Bipyridine-4,4′-dicarboxylic acid was complexed with [IrCl(COD)]2 in the presence of bis(pinacolato)diboron. The resulting iridium catalyst could be readily separated from the reaction mixture by simple filtration, and the recovered catalyst under a nitrogen atmosphere was still active and could be reused more than 10 times. 相似文献