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81.
Back Cover: Tailored Synthesis of 162‐Residue S‐Monoglycosylated GM2‐Activator Protein (GM2AP) Analogues that Allows Facile Access to a Protein Library (ChemBioChem 20/2016)
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82.
Soichi Hirota Shuhei Inoue Takahito Inoue Yoshifumi Kawai Yasutaka Wada Takashi Noguchi Yukihiko Matsumura 《Korean Journal of Chemical Engineering》2016,33(4):1261-1266
Supercritical water gasification (SCWG) has attracted attention as a technology for utilizing wet biomass. We used a fluidized bed of alumina particles to prevent blockage of a SCWG reactor. A glucose solution was heated in the reactor with and without fluidized alumina particles. In the absence of alumina particles, char particles formed homogeneously in the reactor, but the use of a fluidized bed resulted in accumulation of char particles at the reactor’s exit rather than inside the reactor. Therefore, the fluidized bed was effective at preventing blockage of the reactor. However, the alumina particles did not remove deposits from the reactor’s walls. Instead, the fluidized bed caused larger char particles to form, preventing their adhesion to the reactor’s wall. 相似文献
83.
Novel conductor-backed uniplanar structures, including the nonleaky CPW and slotline, are analyzed and applied to the active antenna design. Both the spectral domain analysis and finite-difference time-domain techniques are used to simulate these circuits and to justify the numerical results. The measured gain of the novel active antenna is 1.7 dB higher than the conventional CPW antenna due to the unidirectional radiation of conductor-backed circuits. © 1996 John Wiley & Sons, Inc. 相似文献
84.
Koji Ouchi Shoichi Ibaragi Ataru Kobayashi Kazuyuki Tanimoto Masataka Makabe Hironori Itoh Kenji Matsubara Tomei Takekawa 《Fuel》1984,63(1):78-83
After solvent extraction of Taiheiyo, Miike and Balmer coals using wash oil under nitrogen atmosphere at 370 °C for 30 min, the extraction yield is always within the additivity law. Further studies used Yallourn, Soyakoishi, Taiheiyo, Horonai, Miike, Shin Yubari, Balmer coals and their blends which were hydrogenated in tetralin, wash oil or creosote oil, with or without catalyst, at 400–450 °C under 10 or 3 MPa of initial hydrogen pressure. When hydrogen is available, the additivity law exists for blended coals, but when the hydrogen supply is deficient, the experimental conversion of blended coals is always lower than calculated conversions. This may be due to the faster consumption of the hydrogen by more reactive coals and thus the less reactive coals were unable to react with hydrogen. 相似文献
85.
Three North Dakota lignites with almost the same percentage carbon have been used to determine the relation between chemical structure and reactivity to hydrogenation. Average structural indices of the lignites were estimated using the pyridine-soluble products after alcohol-alkali treatment, the structural indices obtained at various reaction times being extrapolated to zero reaction time. Hydrogenation was influenced by the average structure, with the lignite having higher aromaticity, higher molecular weight of the pyridine extract from the alcohol-alkali reaction product, larger aromatic ring size and lower content of aliphatic structure, showing a smaller degree of conversion. 相似文献
86.
Sterol composition of 19 vegetable oils 总被引:6,自引:4,他引:6
The unsaponifiables from 19 vegetable oils were divided into a sterol and three other fractions by thin-layer chromatography.
All except olive and palm kernel oils gave the sterol fraction in a large quantity. Compositions of the sterol fractions were
determined by gas liquid chromatography. Identification of each sterol was carried out by gas liquid chromatography and combined
gas chromatograph-mass spectrometry. Campesterol, stigmasterol and β-sitosterol were present in all oils, and a minor amount
of cholesterol in majority of the oils. Brassicasterol occurrence was widespread but its content was extremely small in oils
other than rapeseed oil. Other sterols, presumably δ7-stigmastenol and δ5- and δ7-avenasterol were detected in most of the oils. 相似文献
87.
Sterols,methylsterols, and triterpene alcohols in threeTheaceae and some other vegetable oils 总被引:4,自引:0,他引:4
The unsaponifiables from threeTheaceae (Camellia japonica L.,Camellia Sasanqua Thunb., andThea sinensis L.) oils and alfalfa, garden balsam, and spinach seed oils and shea fat were separated into four fractions: sterols, 4-methylsterols,
triterpene alcohols, and less polar compounds by thin layer chromatography. While the sterol fraction was the major one for
the unsaponifiables from alfalfa and spinach seed oils, the triterpene alcohol fraction was predominant for the unsaponifiables
from all other oils. The sterol, 4-methylsterol, and triterpene alcohol fractions were analyzed by gas chromatography. All
the sterol fractions were alike in their compositions, consisting exclusively of Δ7-sterols, such as α-spinasterol and Δ7-stigmastenol as predominant components together with Δ7-avenasterol and 24-methylcholest-7-enol. Obtusifoliol, gramisterol (occasionally accompanied with cycloeucalenol), and citrostadienol,
together with several other unidentified components, were found in the 4-methylsterol fractions from all of the oils except
shea fat. The 4-methylsterol fraction from shea fat showed a characteristic composition containing a large proportion of unidentified
components which had relative retention time greater than that of citrostadienol, while no citrostadienol was detected. β-Amyrin,
lupeol, and butyospermol were major components of the triterpene alcohol fractions from most of the oils, but the fraction
from spinach seed oil contained cycloartenol and 24-methylene-cycloartanol as predominant components. There is a close similarity
in the compositions of unsaponifiables (sterols, 4-methylsterols, and triterpene alcohols) of the threeTheaceae oils. Two sterols, α-spinasterol and Δ7-stigmastenol, and five triterpene alcohols were isolated from tea seed oil. Moreover, five unidentified components beside
parkeol, butyrospermol, α-amyrin, and lupeol were isolated from the triterpene alcohol fraction of shea fat. 相似文献
88.
1 Introduction MEMS (MicroElectroMechanicalSystem )basedonsemiconductormicrofabricationplaysim portantrolesforexampleinthe peripheryofITsystems.NEMS (NanoElectroMechanicalSys tem)containsnano_scalestructures.Sophisticatedandhighperformancesystemsbasedonth… 相似文献
89.
Rubber bearings used in bridges are exposed to the air and easily attacked by oxygen, even at room temperature, and heat, light, dynamic strain, and liquids. It is usually known that the degradation of polymers often occurs as a nonuniform or heterogeneous process because aged rubber will prevent deterioration from progressing into the inner rubber bearing. Thermal oxidation tests were carried out on natural rubber (NR) blocks at different elevated temperatures using the modulus profiling method. The development of the heterogeneous property profiles in aged rubber bearings is revealed. The NR blocks display the features of a diffusion-limited oxidation and the properties change most significantly at the surface. However, in the interior region beyond the critical depth, NR does not change. The property variations at the block surface and the interior are quantitatively examined, based on which, the relations are clarified among property variation, temperature, aging time, and relative position inside a rubber bearing. An appropriate aging model is established, which is able to predict the aging characteristics in NR bearing. 相似文献
90.
Hyeonjae Kim Yeongsoo Choi Nariyasu Kanuka Hisao Kinoshita Takahito Nishiyama Takao Usami 《Applied Catalysis A: General》2009,352(1-2):265-270
Preparation of Pt-loaded TiO2 nanofibers and their catalytic performance for water gas shift (WGS) reactions have been explained in this work. The Pt-loaded TiO2 nanofibers were obtained by electrospinning poly-ethylene oxide (PEO) aqueous solutions containing Ti(OH)n slurry and Pt nanoparticles at room temperature, followed by calcination at 773 K for 4 h. The calcined nanofibers were rougher than the nanofibers of PEO/Ti(OH)n/Pt due to the PEO degradation and oxidation of Ti(OH)n to TiO2. Diameters of the Pt-loaded TiO2 nanofibers ranged between 200 and 900 nm. Catalytic activity of the Pt-loaded TiO2 nanofibers for water gas shift (WGS) reactions was evaluated and it was observed that their activity was 5–7 times higher than that of a bulk catalyst. Such improvement is attributed to the larger surface area of the nanofiber catalyst compared to that of the bulk catalyst. To the best of our knowledge, this is the first demonstration of a synthesis of Pt-loaded TiO2 nanofibers from a Ti(OH)n nanoparticle slurry using electrospinning and its application to WGS reactions. 相似文献