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排序方式: 共有555条查询结果,搜索用时 31 毫秒
81.
Tomomichi Okano Naoyuki Egawa Masami Fujiwara Masahiro Fukuda 《Journal of the American Oil Chemists' Society》1996,73(1):31-37
Sodium α-sulfonated, fatty acid polyethylene glycol monoesters [C
m
H2m+1CH(SO3Na)COO(C2H4O)
n
H] and diesters [C
m
H2m+1CH(SO3Na)COO(C2H4O)
n
COCH(SO3Na)C
m
H2m+1], wherem=10–16 andn=1–35, were prepared by esterification of α-sulfonated, fatty acids with polyethylene glycols, followed by neutralization
with NaOH. Crude products were purified by reversed-phase column chromatography on an octadecyl-modified silica gel. Characteristic
solution behavior of these α-sulfonated fatty acid esters was, examined, and the following features were observed. All monoesters
prepared in this work had Krafft points below 0°C and also possessed good calcium stabilities. Critical micelle concentrations
of the monoesters increased monotonously, as a rule, with an increase in the number of oxyethylene units. These results suggest
that the polyethylene glycol residue of the monoester behaves as a hydrophile. On the other hand, diesters possessed high
water solubility, low foamability, and critical micelle concentrations that were lower by a factor of ten compared to those
of the monoesters. 相似文献
82.
Taher Sharshar Kotoyuki Okano Yoichi Kawase 《Nuclear instruments & methods in physics research. Section B, Beam interactions with materials and atoms》1992,70(1-4):259-264
The basic characteristics of a N2-jet system coupled with a surface-ionization type ion source have been investigated at KUR-ISOL. The yields of transported activities and ionized ions have been measured under various conditions for both the He- and N2-jets. The effects of N2 gas upon the ionization and skimmer efficiency have been investigated. It was found that N2 gas has almost no effect upon the ionization efficiency, but causes poorer skimmer efficiency than He gas owing to the large opening angle of aerosol particles at the outlet of a capillary. A mixture of He and N2 gases was also tested. 相似文献
83.
Araki Masuyama Tomomichi Okano Mitsuo Okahara 《Journal of the American Oil Chemists' Society》1988,65(11):1830-1833
Amide oxime compounds have become of major interest because they can complex with uranium, gallium and various transition
metal ions. In this work surface active amide oximes were prepared to make some functions of the amide oxime group exhibit
as molecular aggregates in aqueous media. Amide oximes were obtained from nitriles which were prepared by the cyanoethylation
of alcohol ethoxylates with a monodispersed oligo(oxyethylene) group. Surface active properties of these compounds were measured
under various conditions and were compared with nonionics of the alcohol ethoxylate type. The pKa1 values of these amide oximes were about five, and they acted as cationic surfactants under acidic conditions and nonionic
ones under neutral and basic conditions. When they served as nonionics, the cloud point, CMC, γCMC and foaming properties of surface active amide oximes were similar to other alcohol ethoxylate nonionics. 相似文献
84.
Hepatocyte growth factor (HGF) stimulates inositol 1,4,5-trisphosphate (InsP3) formation in rat primary cultured hepatocytes, which is inhibited by the pretreatment with a tyrosine kinase inhibitor, genistein. This InsP3 production was coincident with tyrosine phosphorylation of phospholipase C gamma (PLC gamma), detected in immunoprecipitates with anti-PLC gamma, suggesting activation mechanism of PLC gamma by tyrosine phosphorylation. However, in human hepatocarcinoma HepG2 cells, HGF, which suppresses cell growth, causes neither phosphorylation of PLC gamma nor InsP3 formation. The results suggests that PLC gamma in normal hepatocytes was activated by HGF through tyrosine kinase of HGF receptor. 相似文献
85.
Tomiaki Furuya Kunihiko Sasaki Yoshio Hanakata Toshiyuki Ohhashi Masahiko Yamada Toshiaki Tsuchiya Yutaka Furuse 《Catalysis Today》1995,26(3-4):345-350
The hybrid catalytic combustor concept proposed by the authors has an advantage concerned with catalyst durability, because the catalyst is maintained below 1000°C even for application to 1300°C class gas turbines. A full-scale hybrid catalytic combustor has been designed for a 200 MW (1300°C) class gas turbine. The catalyst bed was 450 mm in diameter and consisted of a Pd/ alumina washcoat on a cordierite monolith. In experiments, the combustor has demonstrated the capability of meeting the NOx emission level of SCR (selected catalytic reduction) during atmospheric pressure testing. To predict the catalyst performance at an elevated pressure, the characteristics of the catalyst were studied using a small scale reactor test, and a material property test using a DTA/TGA-Q.MASS system. The catalyst showed a higher activity in the oxidized state (PdO) than in the metallic state (Pd). This activity difference was governed by the equilibrium of the oxygen release from PdO in bulk. It was considered that oxidation rate of the metallic Pd in bulk was not so high and this caused self-oscillation for the Pd catalyst around the temperature of the oxygen release equilibrium. Even below the temperature of the oxygen release equilibrium, both surface and bulk (lattice) oxygen of the PdO was consumed by the methane oxidation reaction, and resulted in a lack of surface oxygen on the catalyst. This caused a reversible decrease in the catalyst activity during combustion testing, and indicated that the oxygen dissociation step was a rate limiting step in the catalytic combustion. 相似文献
86.
LIM-kinase 1 (LIMK1) and 2 (LIMK2) are members of a novel class of protein kinases containing two LIM motifs at the N-terminus. The LIM motif is thought to be involved in protein-protein interactions. We report here evidence that LIMK1 self-associates and also associates with LIMK2. In vivo and in vitro binding analyses using variously deleted mutants of LIMKI revealed that the self-association of LIMK1 was caused by interaction between the N-terminal LIM domain and the C-terminal kinase domain. The association of LIMK1 with itself and with LIMK2 is important for understanding how activities and functions of LIMK family kinases are regulated. 相似文献
87.
88.
Using the instrumented fuel assemblies (IFA) installed in the Japan Power Demonstration Reactor (JPDR)-II core, fluctuations of the inlet and outlet channel flow rates were observed under both conditions of at-power operation and cold core flow circulation. The correlation analysis revealed that the flow fluctuations in any IFA channel showed almost uncorrelated cross-covariance function with other IFA channel flow. To explain the mechanism of the channel flow fluctuations, some hypothetical idea is introduced. 相似文献
89.
Electrical properties of phosphorus-implanted silicon annealed by a single shot of a high-power pulsed electron beam have been studied by differential Hall-effect and sheet-resistivity measurements. Nearly 100% electrical activation of implanted phosphorus can be obtained after electron-beam annealing at an incident energy density of 0.92 J/cm2. Uniformly distributed carrier concentration profiles have been formed by electron-beam annealing. 相似文献
90.