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171.
The c-axis polarity of ZnO crystals growing in the c direction was investigated for crystals grown by chemical reaction in the vapor, by VLS mechanism and by chemical vapor deposition. In the initial growth stage ZnO crystals nucleate both in the +c and -c directions in each type of growth. In growth by chemical reaction in the vapor, a higher growth rate of the crystal in the +c direction results in dominant growth of large crystals in this direction. The difference in the growth rate is attributed to a higher effective surface energy of the Zn atom surface than that of the O atom surface. On the other hand, in VLS growth long whiskers and needles grow in both c directions. This fact indicates that the difference in the growth rates between the two c directions decreases in VLS growth. 相似文献
172.
Giuliano Freddi Patrizia Monti Masanobu Nagura Yohko Gotoh Masuhiro Tsukada 《Journal of Polymer Science.Polymer Physics》1997,35(5):841-847
Structural changes of tussah (Antheraea pernyi) silk fibroin films induced by heat treatment were studied as a function of the treatment temperature in the range 200–250°C. The DSC curve of tussah films with α-helix molecular conformation displayed characteristic endo and exo peaks at 216 and 226°C, respectively. These peaks first weakened and then completely disappeared after heating at 230°C. Accordingly, the TMA thermal shrinkage at 206°C disappeared when the films were heated at 230°C. The onset of weight loss was monitored at 210°C by means of TG measurements. X-ray diffraction profiles gradually changed from α-helix to β-sheet crystalline structure as the treatment temperature increased from 200 to 250°C. On raising the heating temperature above 200°C, the intensity of IR and Raman bands characteristic of β-sheet conformation increased in the whole ranges of amide and skeletal modes. The sample treated at 200°C showed a spectral pattern intermediate between α-helix and β-sheet molecular conformation. The IR marker band for random coil structure, still detectable at 200°C, disappeared at higher treatment temperatures. Spectral changes attributable to the onset of thermal degradation appeared at 230°C. © 1997 John Wiley & Sons, Inc. J Polym Sci B: Polym Phys 35: 841–847, 1997 相似文献
173.
Ranganathan Kandasamy Masanobu Yamanaka Yasukasu Izawa Sadao Nakai 《Optical Review》2000,7(2):149-151
Using Jones matrix formulation, the theoretical calculations of birefringence compensation technique for a quarter-wave plate scheme are presented. This scheme was proposed and experimentally demonstrated by W. A. Clarkson et al. (Opt. Lett. 24 (1999) 820). In the present paper we have theoretically confirmed that using this method, even in principle, complete compensation is not possible. However, it is shown quantitatively that this scheme does makes possible effective compensation for the birefringence in as few as several tens of watts of pumping power region, which is an attractive feature for laser-diode (LD) pumped solid-state laser systems. We also found good agreement between our theoretical calculations and experimental results obtained by W. A. Clarkson et al. For example, from the analysis we show that only < 0.1% loss will be generated by about 10 W of heat deposited in the rod. This corresponds to about 30 W of LD pump power, which may generate from 6 to 10 W output power depending upon the conversion efficiency of type lasers 相似文献
174.
Masato Goto Yoshiyuki Kani Masanobu Tsuchimoto Shigeru Ohba Hideaki Matsushima Tadashi Tokii 《Acta Crystallographica. Section C, Structural Chemistry》2000,56(1):7-11
In the crystals of the five title compounds, tetrakis‐(μ‐3,3‐dimethylbutyrato‐O:O′)bis(ethanol‐O)dicopper(II)–ethanol (1/2), [Cu2(C6H11O2)4(C2H6O)2]·2C2H6O, (I), tetrakis(μ‐3,3‐dimethylbutyrato‐O:O′)bis(2‐methylpyridine‐N)dicopper(II), [Cu2(C6H11O2)4(C6H7N)2], (II), tetrakis‐(μ‐3,3‐dimethylbutyrato‐O:O′)bis(3‐methylpyridine‐N)di‐copper(II), [Cu2(C6H11O2)4(C6H7N)2], (III), tetrakis‐(μ‐3,3‐dimethylbutyrato‐O:O′)bis(4‐methylpyridine‐N)di‐copper(II), [Cu2(C6H11O2)4(C6H7N)2], (IV), and tetrakis‐(μ‐3,3‐dimethylbutyrato‐O:O′)bis(3,3‐dimethylbutyric acid‐O)dicopper(II), [Cu2(C6H11O2)4(C6H12O2)2], (V), the dinuclear CuII complexes all have centrosymmetric cage structures and (IV) has two independent molecules. The Cu?Cu separations are: (I) 2.602 (3) Å, (II) 2.666 (3) Å, (III) 2.640 (2) Å, (IV) 2.638 (4) Å and (V) 2.599 (1) Å. 相似文献
175.
Hiroo Nakagawa Yoshiyuki Kani Masanobu Tsuchimoto Shigeru Ohba Hideaki Matsushima Tadashi Tokii 《Acta Crystallographica. Section C, Structural Chemistry》2000,56(1):12-16
In the crystals of bis(pyridine‐N)tetrakis(μ‐trimethylsilylacetato‐O:O′)dicopper(II), [Cu2(C5H11O2Si)4(C5H5N)2], (I), the dinuclear CuII complexes have cage structures with Cu?Cu distances of 2.632 (1) and 2.635 (1) Å. In the crystals of bis(2‐methylpyridine‐N)tetrakis(μ‐trimethylsilylacetato‐O:O′)dicopper(II), [Cu2(C5H11O2Si)4(C6H7N)2], (II), bis(3‐methylpyridine‐N)tetrakis(μ‐trimethylsilylacetato‐O:O′)dicopper(II), [Cu2(C5H11O2Si)4(C6H7N)2], (III), and bis(quinoline‐N)tetrakis(μ‐trimethylsilylacetato‐O:O′)dicopper(II), [Cu2(C5H11O2Si)4(C9H7N)2], (IV), the centrosymmetric dinuclear CuII complexes have a cage structure with Cu?Cu distances of 2.664 (1), 2.638 (3) and 2.665 (1) Å, respectively. In the crystals of catena‐poly[tetrakis(μ‐trimethylsilylacetato‐O:O′)dicopper(II)], [Cu2(C5H11O2Si)4]n, (V), the dinuclear CuII units of a cage structure are linked by the cyclic Cu—O bonds at the apical positions to form a linear chain by use of a glide translation. 相似文献
176.
Determination of inorganic anions in human saliva by zwitterionic micellar capillary electrophoresis
Masanobu Mori Wenzhi Hu James S. Fritz Hirohito Tsue Takashi Kaneta S. Tanaka 《Analytical and bioanalytical chemistry》2001,370(4):429-433
Capillary electrophoresis (CE) using sulfobetaine-type zwitterionic micelles as the background electrolyte (BGE) has been used to determine inorganic anions in human saliva. The zwitterionic micelles resulted in unique migration behavior for the separation of inorganic anions. They also prevented adsorption of proteins on the inner wall of the capillary. These properties of the zwitterionic micelles enabled the direct determination of inorganic anions in human saliva. Three species of inorganic anions, NO2 –, NO3 –, and SCN–, were found in real samples and the analysis was achieved within 3 min. Direct UV-absorption was used as the detection method and the detection limits for these anions were 2.0, 1.0, and 5.0 μmol L–1, respectively (0.09, 0.06, and 0.30 μg mL–1). 相似文献
177.
178.
Ahmed Jalal Uddin Yusuke Mashima Yutaka Ohkoshi Yasuo Gotoh Masanobu Nagura Akinobu Sakamoto Ryuma Kuroda 《Journal of Polymer Science.Polymer Physics》2006,44(2):398-408
Drawing behavior, flow drawing, and neck drawing, was studied for isotacticpolypropylene fibers in CO2 laser drawing system, and the fiber structure and the mechanical properties of drawn fibers were analyzed. For a certain laser power, flow drawing of polypropylene (PP) was possible up to draw ratio (DR) 19.5. Though the drawing stress was very low, the flow‐drawn PP fiber exhibited oriented crystal structure and improved mechanical properties. On the other hand, neck‐drawing was accomplished from DR 4 to 12, with significant increase in drawing stress that enhanced the development of fiber structure and mechanical properties. Unlike PET, the drawing stress depends not only on the DR, but on irradiated laser power also. The 10–12 times neck‐drawn fibers were highly fibrillated. The fibers having tensile strength 910 MPa, initial modulus 11 GPa, and dynamic modulus 14 GPa were obtained by single‐step laser drawing system. © 2005 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 44: 398–408, 2006 相似文献
179.
Toshihiro Okamoto Kenji KakutaniTomomi Yoshizaki Masanobu HaraguchiMasuo Fukui 《Surface science》2003,544(1):67-73
We have proposed a way to evaluate the reflectance of surface plasmon polaritons (SPP) at a Ag step barrier from an experiment using the attenuated total reflection structure consisting of ultra-thin metal films sandwiched by dielectrics with nearly identical refractive index. At a wavelength of 632.8 nm, for a long-range SPP (L-SPP) excited in a Ag film of 5.7 nm in thickness, the reflectance at Ag step barriers of 766 nm in height was evaluated to be 7.9 × 10−2. 相似文献