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91.
Hirosuke Oku Jyutaro Shudo Kunio Mimura Akinori Haratake Junichi Nagata Isao Chinen 《Lipids》1995,30(2):169-172
A neutral lipid class was isolated by thin-layer chromatography from the skin surface lipids of the hairless mouse. The fraction
migrated faster than triglycerides and had a migration rate similar to that of diacyl alkanediols (diester wax). Upon deacylation,
however, the long-chain diols were identified as 1-alkylglycerol ethers based on their chromatographic properties and on the
mass spectra of their nicotinylidene derivatives. Thus, the skin lipid fraction was identified as 1-O-alkyl-diacylglycerol. The alkyl moieties were all saturated and even-numbered and ranged in chainlength from C16 to C22 with 1-O-hexadecylglycerol amounting to 34% of the total glycerol ether moieties. The fatty acids derived from this lipid fraction
were mostly monoenoic with chainlengths ranging from C16 to C24. The major acyl component was eicosenoic acid (20∶1) representing 61% of the total fatty acids. 相似文献
92.
A new non-heating technique was developed for the sterilization of food stuff. Applying a roller compactor, ultra-high pressure sterilization has experimentally demonstrated its ability to sterilize dry powders, such as corn flour and Chinese herbs, with little quality deterioration. Also, the degree of food sterilization was found correlated well with the linear press forces between the rollers, roller gaps, and number of compaction passes. In comparison to the conventional high pressure sterilization technique, the new dry continuous processing method has the advantage of lower investment cost and is more versatile for sterilizing various food powders. 相似文献
93.
A computerized thermodynamics-oriented procedure for reaction system synthesis is proposed. First, hierarchy structure of chemical reactions is discussed and the reaction system is categorized into three types; (1) combination with a heat source or sink, (2) combination with a reaction donor, and (3) decomposition of target reaction into subtargets. Then, the algorithm to find subtarget reactions and/or donor reactions is presented. 相似文献
94.
The minimum sequence lengths (nc) of vinyl acetate (VAc) units necessary to form a colored iodine complex were determined to be 4 and 17 for radically polymerized VAc/vinyl propionate (VPr) and VAc/isopropenyl acetate (IPAc) copolymers, respectively. The iodine affinities (I/VAc) of VAc/VPr copolymers (SP-series) obtained by propionylation of partially saponified polyvinyl acetate (PVAc) were remarkably affected by the saponification conditions. An increase of the water content in acetone/water mixture as saponification solvent brought about a decrease of the iodine affinities of the SP-series. The dependence of the iodine affinity on the saponification of monomer units in the SP-series was compared with that in the radically polymerized VAc/VPr copolymers by taking the sequence probability as the measure of monomer unit distribution. The results strongly supported an occurence of the slide fastener reaction at high degrees of saponification, which was well-known in the saponification of PVAc. Furthermore, it was found that the saponification mode of PVAc at low degrees of saponification was influenced uniquely by the water content in saponification solvents and the saponification temperature. 相似文献
95.
Jiunn Yih Lee Hisashi Tanaka Hideo Takezoe Atsuo Fukuda Eiichi Kuze Hiroshi Iwanaga 《应用聚合物科学杂志》1984,29(3):795-802
A novel method is proposed of preparing thin Ag–Hg alloy on PAAm film surface at room temperature: The film of interest is formed by holding PAAm aqueous solution with AgNO3 in Hg-saturated atmosphere. Two kinds of films, one of which is a conductor and the other an insulator, can be selectively formed with pH-controlled PAAm solution by ammonia. The conducting surface is assigned to the α phase of Ag–Hg alloy by means of X-ray analysis. Potentiometric titration and IR spectral studies suggest the existence of PAAm–Ag+ complexes. On the basis of their structure and the oxidation and reduction potential of Ag+ and Hg2+, the mechanism of film formation is also discussed. 相似文献
96.
M. Shimada M. Koizumi A. Tanaka T. Yamada 《Journal of the American Ceramic Society》1982,65(4):c48-c48
Temperature dependence of KIC values for Si3 N4 bodies sintered at high pressures without additives was studied from room temperature to 1400°C. Little change in KK was found in this range. 相似文献
97.
The pre-treatment of a silica-supported gallium oxide catalyst with H2 at 823 K increased the yield of aromatics and the selectivity to aromatics in the dehydrogenation of propane over the catalyst at 823 K. Gallium oxide in the catalyst was partially reduced with H2 at 823 K. NH3 desorption and DRIFTS studies on the gallium oxide catalyst suggest that the dehydrogenation of propane over a silica-supported gallium oxide catalyst would proceed in the following way: (1) the dehydrogenation of propane to produce propene would occur on Ga sites including Gaδ+–H sites and (2) the aromatization of propene to aromatics on Ga–O–H acid sites. 相似文献
98.
Kikuo Maekawa Makoto Yamazaki Toshinobu Ogiso Takehiko Maruyama Hideki Ogura Wakako Kashino Hanae Koiso Masaya Yamaguchi Makiro Tanaka Yasuharu Den 《Language Resources and Evaluation》2014,48(2):345-371
The balanced corpus of contemporary written Japanese (BCCWJ) is Japan’s first 100 million words balanced corpus. It consists of three subcorpora (publication subcorpus, library subcorpus, and special-purpose subcorpus) and covers a wide range of text registers including books in general, magazines, newspapers, governmental white papers, best-selling books, an internet bulletin-board, a blog, school textbooks, minutes of the national diet, publicity newsletters of local governments, laws, and poetry verses. A random sampling technique is utilized whenever possible in order to maximize the representativeness of the corpus. The corpus is annotated in terms of dual POS analysis, document structure, and bibliographical information. The BCCWJ is currently accessible in three different ways including Chunagon a web-based interface to the dual POS analysis data. Lastly, results of some pilot evaluation of the corpus with respect to the textual diversity are reported. The analyses include POS distribution, word-class distribution, entropy of orthography, sentence length, and variation of the adjective predicate. High textual diversity is observed in all these analyses. 相似文献
99.
Tetsuya Tanigami Kanna Kai Koji Tanaka Shuji Matsuzawa 《Journal of Inorganic and Organometallic Polymers》2003,13(4):237-253
Poly[bis(-phenoxyethoxy)phosphazene] [PBPEP] had been shown in our previous paper to be a very useful polymer for investigating the crystallization mechanism of polymers, as the crystallization rate of PBPEP is extraordinarily small when isothermally crystallized from the melt. The crystallization of the low molecular weight oligomers of PBPEP was first studied in comparison to the high molecular weight polymers. The oligomer-rich fraction was obtained by fractionation of the as-polymerized sample, which had a broad molecular weight distribution. The fractions thus obtained were characterized by solution viscometry and size exclusion chromatography. The melting temperature and the growth rate of the spherulite from the melt were investigated by differential scanning calorimetry and optical microscopy. The growth rate was one or two orders of magnitude smaller in the oligomer-rich fraction than in the other high molecular weight fractions. A collapsed spherulite appeared in the oligomer-rich fraction at high crystallization temperatures. It is speculated that in the oligomer-rich fraction there is an excess free energy due to defects in the crystal phase. This defect is considerably larger in the oligomer-rich fraction than in the other fractions because a large quantity of short length chains is present. 相似文献
100.
The compositions of ester- and amide-linked fatty acids from ceramides of human vernix caseosa were described with emphasis
on the distribution of the branched-chain fatty acid (BCFA). Two novel ceramides were isolated from vernix caseosa in the
course of this study: the acylated type of esterified α-OH-hydroxyacid/sphingosine ceramide (Cer[EAS]) and nonacylated type
of non-OH fatty acid/hydroxysphingosine ceramide (Cer[NH]). Their chemical structures were identified by nuclear magnetic
resonance and chemical procedure. The Cer[EAS] was an acylceramide and consisted of the highest concentrations of ester- and
amide-linked BCFA (62 and 67%, respectively). The iso- or anteiso-branching structures of the aliphatic chains were confirmed
by the mass spectra of their picolinyl or pyrrolidide derivatives. As a whole, amide-linked fatty acids of ceramides 1–7 and
Cer[NH] were normal types of straight-chain fatty acids with or without α- or ω-hydroxylation. The BCFA concentrations of
amide-linked fatty acids in these ceramides (ceramides 1–7 and Cer[NH]) were low and less than 10%. The BCFA thus occurred
exclusively in a novel acylceramide of Cer[EAS] in the vernix caseosa. 相似文献