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1.
Ryohei Hanayama Kenichi Hibino Shin’ichi Warisawa Mamoru Mitsuishi 《Optical Review》2004,11(5):337-343
Wavelength scanned interferometry allows the simultaneous measurement of top surface shape and optical thickness variation of a transparent object consisting of several parallel surfaces. Interference signals from these surfaces can be separated in frequency space, and their phases are detected by discrete Fourier analysis. However, these signal frequencies are shifted from the detection frequency by the refractive index dispersion of the object and a nonlinearity of the wavelength scanning. The Fourier analysis is sensitive to the detuning of the signal frequency and suffers from the multiple-beam interference noise. Conventional error-compensating algorithms cannot be applied to an object consisting of more than three reflecting surfaces. We derive a new 2N-1 sample error-compensating algorithm, which allows the phase detection of any order of harmonic frequency among the interference signals. The new algorithm suppresses the effect of signal frequency detuning as well as the multiple-beam interference noise and can be applied to the measurement of complex objects consisting of more than three reflecting surfaces. 相似文献
2.
Kazuhiko Nakano Toshihiro Nakamura Izumi Nakai Akira Kawase Makoto Imai Mikio Hasegawa Yohichi Ishibashi Isamu Inamoto Kazuhuyu Sudou Masaru Kozaki Akira Tsuruta Akihiro Ono Kazutoshi Kakita Mamoru Sakata 《Analytical sciences》2006,22(9):1265-1268
The Japan Society for Analytical Chemistry has developed some new plastic certified reference materials (CRMs) for the analysis of mercury in polyester disks using XRF analysis. These CRMs (named as JSAC 0621-0625) were prepared by casting polyesters including a toluene solution of organometallic compounds as a standard. Concentrations of the five levels of mercury ranged from 0 to 250 mg/kg. Homogeneity tests of prepared disks had shown excellent results. Interlaboratory comparison study for the certification was performed by 15 laboratory participants. The z-scores in robust statistical method was applied for the evaluation of outliers. The certified values were assigned after discarding outliers. The uncertainties of certified values were determined as the confidence levels of 95%. 相似文献
3.
4.
Tomoya Kinumi Kazuo Tsujimoto Mamoru Ohashi Reiko Hara Tomiyuki Hara Koichi Ozaki Miho Saka Yuko Katsuta Akimori Wada Masayoshi Ito 《Photochemistry and photobiology》1993,58(3):409-412
Abstract— 3, 7-Dimethyl-2, 4, 6, 8, 10-dodecapentaenal was synthesized for reconstitution of the retinochrome analog. Its opsin shift was 1000 cm 1 smaller than that of native retinochrome, whose chromophore contains the same number of double bonds. The conformational change from 6-s-trans to 6-s-cis , as figured in a retinal molecule, plays an important role in the formation of the retinochrome analog, based on the estimation of opsin shifts for retinal analogs locked in the 6-s conformation. Thus the conformation of the 6–7 single bond in the native retinochrome was suggested to be 6 -cis . Analysis of the circular dichroic spectra of retinochrome analogs revealed that the 6-s conformation is independent of the appearance of the β-band. The stereoselectivity in the photoisomerization of the retinal analogs by a retinochrome template depends on the hydrophobic binding in the region of the β-ionone ring. 相似文献
5.
Phase transition of water restrained by curdlan suspension
annealed at a temperature from 20 to 110°C was investigated by differential
scanning calorimetry (DSC). The melting temperature of water restrained by
annealed curdlan discontinuously decreased at around 60°C, while the amount
of bound water calculated from enthalpy of melting increased at 60°C,
regardless of water content. Using a highly sensitive DSC, curdlan suspension
with various concentrations was studied. It was found that an endothermic
transition was observed at ca. 58°C in a wide range of concentrations.
The transition observed at 60°C is thermo-reversible and both temperature
and transition enthalpy are constant even after gel formation. Well equilibrated
suspension at a temperature lower than 60°C formed no gel. 相似文献
6.
Chatani N Amako K Tobisu M Asaumi T Fukumoto Y Murai S 《The Journal of organic chemistry》2003,68(4):1591-1593
The reaction of benzofuran-2,3-dione derivatives 1 with CO and alkenes (or alkynes) results in a carbonylative [2+2+1] cycloaddition in which the ester-carbonyl group is incorporated into a two-atom assembling unit to give spirolactone derivatives 2. This reaction provides the first example of an ester-carbonyl group participating in a carbonylative cycloaddition reaction. 相似文献
7.
Ogawa T Araki M Miyamae T Okayama T Hagiwara M Sakurada S Morikawa T 《Chemical & pharmaceutical bulletin》2003,51(7):759-771
To improve the oral bioavailability of a dermorphin tetrapeptide analog, N(alpha)-1-iminoethyl-Tyr-D-MetO-Phe-MebetaAla-OH (III), which has a potent analgesic activity after oral administration, various derivatives were synthesized to increase lipophilicity by esterification of the C-terminal carboxyl group and/or acylation of the phenolic hydroxyl group on Tyr1. Antinociceptive activity was evaluated after subcutaneous or oral administration using the mouse tail pressure test. As a result, increased antinociceptive activity after oral administration as well as an improved ED50(p.o.)/ED50(s.c.) ratio, which is an indicator of oral bioavailability, were found for some compounds. With regard to the improvement of bioavailability, derivatives with acylation of the phenolic hydroxyl group on Tyr1 showed better results than derivatives with esterification of the C-terminal carboxyl group. In particular, an ED50(p.o.)/ED50(s.c.) ratio equivalent to that of morphine was found for an acetylated derivative, N(alpha)-1-iminoethyl-Tyr(COMe)-D-MetO-Phe-MebetaAla-OH (7a), as well as for a methoxycarbonylated derivative, N(alpha)-1-iminoethyl-Tyr(CO2Me)-D-MetO-Phe-MebetaAla-OH (7l). 相似文献
8.
Osamu Matsumoto Eiji Hayami Mamoru Samejima Yasushi Kanzaki 《Plasma Chemistry and Plasma Processing》1984,4(1):33-42
The nitriding of titanium with argon-nitrogen (3%) and argon-nitrogen (3%)-hydrogen (2%) plasma jets at pressures of 190 torr was studied. The reaction kinetics obeyed mainly a parabolic law. The parabolic kinetic constants were 10–10–10–8 g2 cm–4 s–1, which were 2–3 orders of magnitude larger than those in R.F. discharges. From emission spectroscopy, nitrogen atoms in the excited states were observed. The nitrogen atoms can promote the nitriding reaction. The effect of the addition of hydrogen to nitrogen is also briefly discussed. 相似文献
9.
Manabu Tsujino Tetsuhiko Isobe Mamoru Senna 《Journal of Sol-Gel Science and Technology》2000,19(1-3):785-789
A tetraethoxysilane (TEOS)-derived sol aged for 0 h–6 h at room temperature was mixed with a polyurethane (PU) matrix. A composite of silk fibroin (SF) powders and acrylamide (AAm) was dispersed in the sol-PU mixture and dried isothermally at temperatures between 25°C and 120°C to obtain composite films. Three competitive reactions take place, i.e., those between silica-silica, SF-PU and silica-organic phases, during formation of the composite films. These reactions determine the properties such as morphology and homogeneity of the composite films. IR absorption bands for amide groups (–CONH–), C=O (amide I, 1730 cm–1) and N–H (amide II, 1530 cm–1) become larger with decreasing aging time of TEOS-derived sol, or increasing drying temperature. DTA exothermic peak due to the thermal decomposition of SF-AAm composite, on the composite films prepared from the 0 h-aged sol or dried at more than 50°C, shifts toward higher temperature by 44 K or more than 63 K respectively, as compared to the SF-AAm composite. Shorter aging time of TEOS-derived sol and higher drying temperature increased the extent of dispersibility, among SF-AAm composite, PU and silica, to bring a composite film more homogeneous. 相似文献
10.
The melting process of constrained nylon 6 fibers has been studied to estimate the true melting point of its original crystals.
The melting peak became simpler in shape and shifted to higher temperature with increasing fiber-axis restricting force. When
heating rate, β, was increased, the temperature where the melting curve initially departs from its baseline, Tsm, decreased
steeply in the range of 45 to 60°C min-1, and increased linearly with increasing β above 60°C min-1. By linear extrapolation of Tsm to 0°C min-1, the temperature of ca 190°C was obtained for the melting temperature of the original nylon 6 crystals. This seems to correspond
to the zero-entropy-production melting of the most imperfect crystallites of the nylon 6 fabric.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献