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971.
T. Tsuchiya M. Takeda I. Yamaguchi T. Manabe T. Kumagai S. Mizuta 《Applied Physics A: Materials Science & Processing》2004,79(4-6):1541-1544
A SnO2 film has been prepared by an excimer laser metal organic deposition (ELMOD) process using an XeCl laser. The effects of the laser fluence, shot number, and the pretreatment temperature of the Sn acetylacetonate (Sn-acac) on the crystallization of the SnO2 film were investigated by X-ray diffraction and infrared spectroscopy. When the MO spin-coated film preheated at room temperature on a Si substrate was irradiated by the laser at a fluence of 100 mJ/cm2 and at a repetition rate of 10 Hz for 5 min, a crystallized SnO2 film was successfully obtained without heat treatment. At a fluence of 260 mJ/cm2, the highest crystalline film was formed. On the other hand, when the amorphous SnO2 film was irradiated by the laser at 260 mJ/cm2, the crystallinity of the SnO2 film was improved. SnO2 films were also prepared by conventional thermal MOD in a temperature range from 300 to 900 °C. The crystallinity of the SnO2 films prepared by the ELMOD process at room temperature was higher than that of the films prepared by heating at 900 °C for 60 min. PACS 81.15.Fg; 81.15.-z; 81.16.Mk; 82.50.Hp; 73.61.Le 相似文献
972.
Development of spin‐dependent relativistic open‐shell Hartree–Fock theory with time‐reversal symmetry (I): The unrestricted approach 下载免费PDF全文
An open‐shell Hartree–Fock (HF) theory for spin‐dependent, two‐component relativistic calculations, termed the Kramers‐unrestricted HF (KUHF) method, is developed. The present KUHF method, which is formulated as a relativistic counterpart of nonrelativistic UHF, is based on quaternion algebra and partly uses time‐reversal symmetry. The fundamental characteristics of KUHF are discussed in this study. From numerical assessments, it was revealed that KUHF gives a corresponding solution to nonrelativistic UHF; furthermore, KUHF properly describes spin‐orbit interactions. In addition, KUHF can improve the self‐consistent field convergence behavior in spin‐dependent calculations, for example, for f‐block elements. 相似文献
973.
974.
Non-close-packed silica colloidal crystalline array was immobilized by polymer, and effects of stretching on the change of
the optical properties and microstructure of the colloidal crystalline arrays have been demonstrated. The immobilization was
a two-step polymerization process: the first step was with hydrophilic polyethylene glycol acrylate (PEGA) polymer gel, and
the second step was with 2-hydroxyethyl acrylate polymer matrix. The structure of the three-dimensional array was maintained
during the immobilizing process with lock in periodic order. The peak wavelength of Bragg diffraction of the polymer-immobilized
colloidal crystalline array shifted to shorter wavelength with stretching. The peak shift was caused by the compression of
the polymer proportional to the stretching ratio, and the compression was homogeneous throughout the polymer-immobilized colloidal
crystalline arrays. These results show that by using polymer-immobilized non-close-packed colloidal crystalline array, mechanically
tunable photonic crystals can be realized, and they open the possibility of tuning the microstructure of colloidal crystalline
array for photonic crystal. 相似文献
975.
Jun Kawakami Toru Isobe Yohei Sasaki Shunji Ito Masahiko Nagaki Haruo Kitahara 《Analytical sciences》2005,21(7):729-730
Poly(amide amine) dendrimer with naphthyl units (N8) as a fluorescent chemosensor for metal ions was synthesized. We investigated the metal ion recognition of N8. Large changes in the fluorescence spectra of N8 were observed upon the addition of cadmium and zinc ions. 相似文献
976.
Moonja Jeong Jong-Won Oh Masahiko Taniguchi 《Journal of Mathematical Analysis and Applications》2007,325(2):1295-1305
In this paper we solve the problem of equivalence between annuli and Bell representations, which are canonical planar domains of connectivity 2. We give a necessary and sufficient condition for equivalence as an explicit formula in parameters of the domains. 相似文献
977.
H. Konno K. Tsuchiya R. Yamamoto 《Journal of Optimization Theory and Applications》2007,135(3):399-410
This paper addresses a new class of linearly constrained fractional programming problems where the objective function is defined
as the ratio of two functions which are the sums of the absolute values of affine functions. This problem has an important
application in financial optimization.
This problem is a convex-convex type of fractional program which cannot be solved by standard algorithms. We propose a branch-and-bound
algorithm and an integer programming algorithm. We demonstrate that a fairly large scale problem can be solved within a practical
amount of time.
The research of the first author was supported in part by the Grant-in-Aid for Scientific Research of the Ministry of Education,
Science, Culture and Sports of the Government of Japan, B(2) 15310122 and 15656025. 相似文献
978.
979.
The mesogenicities of 4,4'-dialkyloxyquaterphenyls (DAQP) and dialkyl quaterphenyl-4,4'-dicarboxylates (DCQP) were studied by differential scanning calorimetry, optical microscopy and miscibility tests. The DAQP homologues, for which the number of carbon atoms in the alkyloxy group (n) is 1-9, showed a SA phase, and the higher homologues (n = 9-18) showed a Sc phase. The propyl, butyl and pentyl esters of DCQP showed a SA phase, and the octyl and dodecyl esters showed SA and Sc phases. The isopropyl, isobutyl, 2-ethylhexyl and cyclohexyl esters showed a Sc phase and the branching of the alkyl group strikingly lowered the mesophase thermal stabilities. 相似文献
980.
Reactions of bromobenzene and chlorobenzene with methyl acrylate were carried out in N-methylpyrrolidone (NMP) over a conventional Pd/C catalyst under Heck coupling conditions indicating both heterogeneous and
homogeneous character. Benzene and biphenyl are produced in addition to the Heck coupling product of methyl cinnamate. It
is proposed that the formation of methyl cinnamate and biphenyl proceed homogeneously with dissolved palladium species, while
the formation of benzene takes place heterogeneously on the surface of supported palladium particles or free colloidal particles
formed during the reaction.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献