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181.
Toshiharu Matsuzawa Takao Iwayanagi Hidehito Obayashi Hideki Tomioka 《Microelectronic Engineering》1983,1(3):185-196
New negative photoresists, called MRS-type resists, are successfully applied to deep-UV 1:1 projection printing and 365 nm 10:1 reduction projection printing. The MRS-type resists are characterized by intense absorption of exposure light and absence of swelling in aqueous developer solutions. They resolve steep profile submicron images in a 1.0 μ thick film. They are not adversely affected by reflected light from water surfaces. In order to use MRS-type resists with broader development latitude, optimizing the extent of light absorption is important because the resist profiles strongly depend on development conditions due to increasing solubility towards the resist bottom. 相似文献
182.
In this paper, we describe a new method for detection of single nucleotide polymorphisms (SNPs) by applying the minisequencing principle to a fluorescence microsphere format. The specific primer, which was designed to anneal to its target of genomic DNA fragment immediately upstream of the polymorphic site, was immobilized to carboxylated Luminex microspheres as a probe. The primer was hybridized with genomic DNA fragments containing polymorphic sites and extended one base in the presence of biotin labeled ddNTP and DNA polymerase. After the extension reaction, Streptavidin-phycoerythrin was added to a reaction mixture to combine the biotin labeled with ddNTP. The final reaction products were analyzed by a Luminex 100 instrument. The fluorescence intensity of the Streptavidin-phycoerythrin combined with the extended ddNTP-biotin was used to identify the SNPs. The results showed that this method is highly sensitive, specific, and suitable for quantitative SNP detection. There was a good linear relationship between the mutant allele frequencies and the relative fluorescence intensities produced by mutant and wild-type gene fragments. A mutant allele frequency as low as 1.0% was accurately determined. 相似文献
183.
Bakalova R Zhelev Z Jose R Nagase T Ohba H Ishikawa M Baba Y 《Journal of nanoscience and nanotechnology》2005,5(6):887-894
The present study describes an enhancement of the photoluminescence of CdSe quantum dots under long-term ultraviolet irradiation in organic solvents. The photoenhancement effect followed multiexponential kinetics and was found to depend on several factors: intensity of ultraviolet light, polarity of the solvent, presence of capping agents on the nanocrystal surface, and presence of free Cd and Se ions in the solution. High intensity ultraviolet irradiation provoked a rapid enhancement of the photoluminescence of CdSe nanocrystals, reaching the maximum with subsequent photoluminescence decay. Low-intensity ultraviolet irradiation provoked a comparatively slow enhancement of the photoluminescence of CdSe nanocrystals, reaching saturation after 5-6 hours of irradiation in organic solvents (butanol and chloroform). The photoenhancement effect was reversible or irreversible depending on the additional ingredients. The role of free Cd and Se in these processes was clarified. The results are discussed in the context of ultraviolet induced liberation of free Cd and Se ions from the nanocrystal surface and their hypothetical reversible deposition with trapping of the surface holes and influencing the efficiency of radiative versus nonradiative exciton decay during the enhancement of photoluminescence. 相似文献
184.
Dodecyl and dodecanoyl groups (C12) are attached at the chain ends of poly[N5-(2-hydroxyethyl) l-glutamine] (PHEG), and association behavior of this both-ends hydrophobically modified water soluble polypeptide (C12-PHEG-C12) has been investigated by means of light scattering measurements. Water/ethylene glycol (EG) mixed solvents were used as selective solvent for PHEG block, and PHEG changed its structure from random-coil state to α-helix with increasing EG content in the mixed solvent (WEG). When WEG is less than 0.5, flower-like micelle with C12 associated core and PHEG corona in loop conformation was suggested to be formed. Increase of WEG from 0.5 to 0.6 induced drastic increase of association number and size of the associate, in which many C12 associated cores may be connected by PHEG in bridge conformation. This structure change of associate is considered to be driven by the increase of helix content of PHEG with WEG, which enhances the possibility to form bridge conformation because of its rigidity. Solution preparation method, i.e. order of addition of solvent, was found to influence the structure of associate, although its effect on the helix content of PHEG was negligible. 相似文献
185.
Gamma-ray-induced graft copolymerization of butadiene with vinyl monomers onto PVC was attempted to improve the physical properties of PVC. The Izod impact strength was increased from 2 kg·cm/cm2 to more than 100 kg·cm/cm2 by grafting ca. 10% butadiene. But the tensile strength and melt flow were decreased by the grafting. The electron micrograph showed that the mass of polybutadiene in the graft copolymer had a convenient diameter (0.1–1 μ) for absorbing the impact energy. The weatherability of PVC grafted with butadiene was improved by cografting of butadiene with acrylates and methacrylates which had long side chains. 相似文献
186.
Nanocrystalline Ag/MgO composites were prepared by the ultrafine-powder-compaction method. The structure was investigated for the first time by high-resolution electron microscopy. Nanometre-sized Ag grains and MgO grains in the composites bonded directly without any intermediate phase layer. Certain preferred orientation relationships were observed between the Ag and MgO grains. The nanocrystalline Ag/MgO composites retained their grain size during annealing up to 873 K. Vickers microhardness measurements were performed on the as-compacted and annealed specimens. Generation and propagation of cracks were less active in the nanocrystalline Ag/MgO composites than in a single-phase nanocrystalline MgO. The Vickers microhardness of the nanocrystalline Ag/MgO composites remained up to 1073 K. Hot-pressing deformation tests showed that the nanocrystalline Ag/MgO composites deformed plastically at 1073 K. 相似文献
187.
A fluorescent image analysis method was developed to evaluate lipid hydroperoxide formation in fish muscle. The lipid hydroperoxides
generated in white and dark fish muscles during storage at 5–6°C oxidized 3-perylene diphenylphosphine located in the tissue
to yield the fluorescent derivative, 3-perylene diphenylphosphine oxide (3-PeDPPO). 3-PeDPPO thus obtained was determined
by digital fluorescent image analysis. The 3-PeDPPO fluorescence intensity of white and dark muscle increased during low-temperature
storage (0–24 h) and was clearly correlated with total lipid hydroperoxide levels in muscle extracts, which were determined
by using HPLC based on a triphenylphosphine oxidation method (R
2=0.954). These results suggest that 3-PeDPPO fluorescence, coupled with fluorescent image analysis, is a novel tool for direct
determination of lipid hydroperoxides in fish muscle without a need for extraction of lipid. 相似文献
188.
The thickness of the glass substrate used in liquid crystal displays continues to be decreased from its original thickness of 1.1 mm for the purpose reducing size and weight. The aim of this study was to clarify the influence of the glass substrate thickness during laser scribing with crack propagation caused by laser heating followed by quick quenching. The laser scribe conditions for soda-lime glass substrates with thickness equal to or less than 1.1 mm were obtained in laser irradiation experiments. Two-dimensional thermal elasticity analysis was conducted with a finite element method based on the scribable conditions obtained in the experiment. The laser scribable conditions can then be estimated by the upper limit of the maximum surface temperature, Tmax, and the lower limit of the maximum tensile stress, σtmax, in the cooling area, regardless of the glass substrate thickness. There is a substrate thickness with which the maximum tensile stress σtmax becomes the largest under each scribe condition. The substrate thickness with which σtmax becomes the largest is obtained at a faster scribe velocity for thinner glass substrate and at slower scribe velocity for thicker glass substrate. Owing to these relations, the crack depth also has almost the same tendency as σtmax. 相似文献
189.
In this study, we have carried out fundamental research on lubricant depletion due to laser heating in thermally assisted magnetic recording. In particular, we investigated the effects of lubricant film thickness and lubricant bonding ratio on lubricant depletion. Conventional lubricants Zdol2000 and Ztetraol2000 were used. The lubricant depletion characteristics due to laser heating were found to depend largely on the lubricant film thickness and material. That is, for films thicker than one monolayer, the lubricant depletion depth increased with the laser-irradiation duration, whereas the thickness of the lubricant after laser irradiation on the diamond-like carbon (DLC) films tended to remain at a constant film thickness of one monolayer. The lubricant depletion width gradually increased as the laser irradiation duration increased. The increasing trends for the lubricant depletion width were quantitatively very similar and almost independent of the initial lubricant film thickness. However, for lubricant films with thicknesses less than one monolayer, the lubricant depletion depth was very small. The lubricant depletion width increased remarkably to several hundred micrometers as the laser irradiation duration increased. The lubricant depletion depth and width were much smaller for Ztetraol2000 than Zdol2000. In addition, the lubricant-bonding ratio was found to greatly affect the lubricant depletion characteristics due to laser heating. In other words, the lubricant depletion depth and width decreased as the bonding ratio increased. The lubricant depletion mechanism involves the evaporation of mobile lubricant molecules when the maximum attained temperature is less than 100 °C. Another suggested lubricant depletion mechanism involves the thermocapillary stress effect, which is induced by the disk surface temperature gradient resulting from the non-uniformity of the laser spot intensity distribution. 相似文献
190.
Akio Ohta Daisuke Kanme Hideki Murakami Seiichiro Higashi Seiichi Miyazaki 《Microelectronic Engineering》2009,86(7-9):1650-1653
A stack structure consisting of ~1.5 nm-thick LaOx and ~4.0 nm-thick HfO2 was formed on thermally grown SiO2 on Si(1 0 0) by MOCVD using dipivaloymethanato precursors, and the influence of N2 annealing on interfacial reaction for this stack structure was examined by using X-ray photoelectron spectroscopy and Fourier transform infrared attenuated total reflection. We found that compositional mixing between LaOx and HfO2 becomes significant from 600 °C upwards and that interfacial reaction between HfLayOz and SiO2 proceeds consistently at 1000 °C in N2 ambience. 相似文献