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161.
Shinsuke Miyajima Makoto Sawamura Akira Yamada Makoto Konagai 《Journal of Non》2008,354(19-25):2350-2354
n-Type hydrogenated nanocrystalline cubic silicon carbide (nc-3C–SiC:H) films have been deposited by very high-frequency plasma-enhanced chemical vapor deposition at a low substrate temperature of about 360 °C to apply this material to the window layer of heterojunction crystalline silicon (HJ-c-Si) solar cells. We investigated the effect of in situ doping on deposition rate, crystalline volume fraction and dark conductivity to optimize properties of the material. We also fabricated HJ-c-Si solar cells with a n-type nc-3C–SiC:H window layer. The solar cells shows high internal quantum efficiency of 0.90 at a wavelength of 400 nm, indicating that n-type nc-3C–SiC:H deposited by VHF-PECVD is a promising candidate of the window layer of HJ-c-Si solar cells. 相似文献
162.
Anisimovsky VV Artamonov AV Bassalleck B Bhuyan B Blackmore EW Bryman DA Chen S Chiang IH Christidi IA Cooper PS Diwan MV Frank JS Fujiwara T Hu J Ivashkin AP Jaffe DE Kabe S Kettell SH Khabibullin MM Khotjantsev AN Kitching P Kobayashi M Komatsubara TK Konaka A Kozhevnikov AP Kudenko YG Kushnirenko A Landsberg LG Lewis B Li KK Littenberg LS Macdonald JA Mildenberger J Mineev OV Miyajima M Mizouchi K Mukhin VA Muramatsu N Nakano T Nomachi M Nomura T Numao T Obraztsov VF Omata K Patalakha DI 《Physical review letters》2004,93(3):031801
An additional event near the upper kinematic limit for K+-->pi(+)nunu; has been observed by experiment E949 at Brookhaven National Laboratory. Combining previously reported and new data, the branching ratio is B(K+-->pi(+)nunu;)=(1.47(+1.30)(-0.89))x10(-10) based on three events observed in the pion momentum region 211
相似文献
163.
Nakamura H Miyajima Y Takei T Kasaoka S Maruyama K 《Chemical communications (Cambridge, England)》2004,(17):1910-1911
The nido-carborane lipid, which has a double-tailed moiety, was synthesized from heptadecanol in 5 steps. Analysis in a transmission electron microscope by negative staining with uranyl acetate showed that the lipid formed a stable vesicle in which calcein was encapsulated. The lipid was incorporated into distearoylphosphatidylcholine (DSPC) liposomes at a very high concentration. 相似文献
164.
Hosoya N Takegami R Suzumura J Yada K Koyasu K Miyajima K Mitsui M Knickelbein MB Yabushita S Nakajima A 《The journal of physical chemistry. A》2005,109(1):9-12
A molecular beam of europium-cyclooctatetraene sandwich nanowires Eu(n)()(COT)(m)() was produced by a laser vaporization synthesis method. The formation mechanism of the nanowires was quantitatively revealed by photoelectron and photoionization spectroscopies of the Eu-COT species, together with supporting theoretical calculations. From these results, it is confirmed that growth processes extending the length of Eu-COT nanowires involve a series of elementary reactions in which efficient charge transfer occurs at the terminal reaction sites. In every elementary step, the reaction proceeds between one reactant having low ionization energy and the other reactant having high electron affinity, probably via a "harpoon" mechanism. 相似文献
165.
A new polymorph of FeAlO3 at high pressure 总被引:1,自引:0,他引:1
Nagai T Hamane D Devi PS Miyajima N Yagi T Yamanaka T Fujino K 《The journal of physical chemistry. B》2005,109(39):18226-18229
Synchrotron X-ray diffraction measurements confirmed that a new polymorph of FeAlO3 could be synthesized at about 1800 K and 72 GPa. This phase can be indexed on an orthorhombic cell and transforms into the trigonal form on release of pressure. The c/a ratio of about 2.71 of the trigonal phase suggests corundum structure of FeAlO3 rather than LiNbO3 or ilmenite structure. This conclusion also suggests that the high-pressure orthorhombic phase could be the Rh2O3(II) structure rather than the GdFeO3-type perovskite structure. 相似文献
166.
The rate constants for the ammonolysis of trimetaphosphate in aqueous solution were determined by measuring the disappearance of trimetaphosphate by use of high-performance liquid chromatography (HPLC). The rate of the reaction was of first order in the concentration of trimetaphosphate. It was found that metal cations added increased the reaction rate. The activation energy and the activation entropy were determined to be 13.6kcal/mole and about -25 eu, respectively. 相似文献
167.
Isao Kanesaka Tsuneyuki Miyajima Kiyoyasu Kawai 《Journal of Molecular Structure》1984,118(3-4):189-195
The IR intensity of ν1 of carbon disulfide is reported in various states. The intensity increases with a decrease in temperature. Less than 10% of the observed intensity can be explained in terms of an electric field applied from an adjacent molecule. On the other hand, nearly half of the intensity is explained in terms of a vibrational coupling of ν1 with ν3 or ν2, which is estimated from dimer models, on the assumption that the observed IR and Raman frequencies can be attributed to dimers. 相似文献
168.
Carbon-13 NMR chemical shifts of several series of aliphatic hydrocarbon derivatives–-substituted methanes, ethanes, isopropanes, n-propanes and n-butanes–-were found to have a linear relationship with σ-electron densities (Qσ) calculated by the method of σ-included ω-HMO. A plot of the 13C NMR chemical shift of a given carbon in a substituted propane versus that of the corresponding carbon in a substituted butane showed a good linearity with a slope of unity. The values of the 13C chemical shifts of the n-butyl derivatives converged rapidly to a constant value as the distance from the substituent increased. Accordingly, the value for the δ-carbon was found to be constant regardless of the substituent. These results show that the 13C NMR chemical shifts of aliphatic hydrocarbon derivatives are mainly dependent on inductive effects. The convergence shown by the experimental results is supported by the calculated results of the Qσ values of the n-butyl derivatives. 相似文献
169.
170.
The binding behavior of dodecylpyridinium chloride to sodium polyphosphate of various degrees of polymerization (DP) was
studied by means of a potentiometric titration method using a surfactant-selective electrode in the presence of 10 mM NaCl
at 30 °C. Binding isotherms were analyzed by direct calculation of a matrix expressing the partition function. It is found
that binding affinity depends prominently on the polymer chainlength when the DP value is less than ca. 35, but becomes nearly
independent on DP thereafter. No binding was observed for linear triphosphate or cyclic trimetaphosphate anions. The picture
that arises for the binding is that the polymer’s end-effect reduces the apparent cooperativity, while the hydrophobic interaction
with neighboring surfactant remains constant because of the short-range nature of the interaction. The so-called end-effect
is associated with a superimposition of electrostatic potentials around the polymer rods. Both the matrix method and the Satake–Yang
equation were carried out for simulations, and the matrix one shows a better fitting with the experimental data for the short-chain
polyelectrolyte.
Received: 1 July 1997 Accepted: 21 August 1997 相似文献