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961.
Naoki Inamoto Shozo Masuda Katsumi Tokumaru Kazuo Tori Masayuki Yoshida Yohko Yoshimura 《Tetrahedron letters》1976,17(41):3711-3714
962.
The IR absorption band of methane adsorbed on an active carbon was obtained at 153 K. The IR nu(1) band of methane (inherently IR inactive in the gaseous phase) adsorbed on the active carbon was induced by the electric field of surface groups, even though the adsorbent was known to be macroscopically hydrophobic. The source of the electric field was suggested to be a hydrogen-bonding surface carboxyl or phenolic OH group. The strength of the electric field was estimated to be 1.13 x 10(5) esu, although the number of sites bearing an electric field was very small. A strong electric field (1.75 x 10(5) esu) was created on the carbon surface by oxidation, and its origin was suggested to be carbonyl groups. Copyright 2000 Academic Press. 相似文献
963.
Ozao R. Ochiai M. Yoshida H. Ichimura Y. Inada T. 《Journal of Thermal Analysis and Calorimetry》2001,64(3):923-932
Gamma-alumina membrane was prepared from anodic (amorphous) alumina (AA) obtained in a sulphuric acid electrolyte. The transformation
scheme, i.e., the crystallization to form metastable alumina polymorphs and the final transition to α-Al2O3 with heating was studied by TG-DTA and X-ray diffraction (XRD) using fixed time (FT) method. When heating at a constant rate,
the crystallization occurred at 900°C or higher and the final formation of α-Al2O3 occurred at 1250°C or higher, which temperatures were higher than the case of using anodic (amorphous) alumina prepared from
oxalic acid electrolyte. Relative content of S of the products was obtained by transmission electron microscope (TEM)-energy
dispersive spectroscopy (EDS). The proposed thermal change of anodic alumina membrane prepared from sulphuric acid is as follows:
1. At temperatures lower than ca 910°C: Formation of a quasi-crystalline phase or a polycrystalline phase (γ-, δ- and θ-Al2O3);
2. 910–960°C: Progressive crystallization by the migration of S toward the surface within the amorphous or the quasi-crystalline
phase, forming S-rich region near the surface;
3. 960°C: Change of membrane morphology and the quasi-crystalline phase due to the rapid discharge of gaseous SO2;
4. 960–1240°C: Crystallization of γ-Al2O3 accompanying δ-Al2O3; and
5. 1240°C: Transition from γ-Al2O3 (+tr. δ-Al2O3) into the stable α-Al2O3.
The amorphization which occurs by the exothermic and the subsequent endothermic reaction suggests the incorporation of SO3 groups in the quasi-crystalline structure.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
964.
Partial revision of the hydrated structure, and determination of the absolute configurations of geraniin and mallotusinic acid lead to structures I-A and II-A, respectively. 相似文献
965.
966.
967.
968.
Adsorption of phenol from an aqueous solution in batch and continuous flow systems using carbon gels with a microhoneycomb structure (carbon gel microhoneycombs, CMHs) was studied. The obtained monolithic CMHs had fairly straight channels, 25–45 μm in diameter, and the thickness of the walls which form the channels was around 5 μm. The CMHs showed 370 times lower hydraulic resistance when compared with a column packed with particles having the same diffusion path length as it. The obtained CMHs have a hierarchical micro-meso porous structure giving BET surface area in the range of 513–1070 m2·g?1.When used for phenol adsorption from an aqueous solution, the CMHs quickly adsorbed phenol at first, and then, the uptake gradually increased, which indicates that the adsorption mechanism is based on not only simple physisorption. The phenol adsorption capacity increased with the increase in carbonization temperature of the CMH and the decrease in its hydrophilicity. CMHs carbonized at temperatures higher than 1073 K showed the highest phenol adsorption capacity which was around 160 mg·g?1. The CMHs could continuously adsorb phenol from aqueous solutions, and their length of unused bed (LUB) values depended on operation conditions but were in the range of 0.3–0.7 cm. The experimental results indicated that carbon cryogels with a microhoneycomb structure have a high potential to be used for effective separation of phenol. 相似文献
969.
Shape‐Memory Platinum(II) Complexes: Intelligent Vapor‐History Sensor with ON–OFF Switching Function
Yasuhiro Shigeta Dr. Atsushi Kobayashi Dr. Tadashi Ohba Dr. Masaki Yoshida Dr. Takeshi Matsumoto Prof. Ho‐Chol Chang Prof. Masako Kato 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(8):2682-2690
A novel platinum(II)–diimine complex, [Pt(CN)2(H2dcphen)] ( 1 ; H2dcphen=4,7‐dicarboxy‐1,10‐ phenanthroline), was synthesized and its vapochromic shape‐memory behavior was evaluated. The as‐synthesized amorphous purple solid, [Pt(CN)2(H2dcphen)]?2 H2O ( 1 P ), exhibited vapochromic behavior in the presence of alcoholic vapors through transformation to a red, crystalline, porous, vapor‐adsorbed form, 1 R?vapor . The obtained 1 R?vapor complex released the adsorbed vapors upon heating without collapse of the porous structure. The vaporfree, porous 1 R?open could detect water or n‐hexane vapor, although these vapors could not induce 1 P ‐to‐ 1 R?vapor transformation, and 1 R?open could easily be converted to the initial 1 P by manual grinding. These results indicate that 1 is a new shape‐memory material that functions through formation and collapse of the porous framework with an emission change upon vapor‐adsorption and grinding; this enables it to exhibit vapor history and ON–OFF switching sensing functions. 相似文献