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721.
722.
723.
Summary Phase diagrams have been determined as a function of temperature for the following binary and ternary systems; water-pentaoxyethylene dodecylether system and water-dodecane systems containing 10, 20, 30, and 40 wt.-% of pentaoxyethylene dodecylether.X-ray diffraction examinations have revealed that the two lyotropic mesophases (neat phase and middle phase) are formed in the binary system. In the ternary systems, the mutual solubility of water and oil increases remarkably at a medium temperature near the phase inversion temperature in emulsion. The marked increase in mutual solubility is illustrated in the phase diagram as a narrow transparent region which has been regarded as a microemulsion. The electrical conductance, viscosity and type of flow behavior of the ternary system vary with temperature, corresponding to the structural changes of the system. The rheograms of the ternary systems have exhibited various types of flow behavior such asNewtonian flow, pseudoplastic flow, thixotropic hysteresis and dilatant hysteresis. Besides, differential scanning analysis has revealed endothermic peaks corresponding to phase transitions.
Zusammenfassung Zustandsdiagramme wurden als Funktion der Temperatur für folgende binäre und ternäre Systeme bestimmt: Wasser-Pentaoxydthylen-Dodecyläther und Wasser-Dodecan mit 10, 20, 30 und 40 Gew.-% von Pentaoxyäthylen-Dodecyläther.Die Röntgen-Diffraktion-Untersuchung ergab, daß zwei lyotropische mesomorphe Phasen (neat"-Phase und middle"-Phase) in dem binären System gebildet werden. In dem ternären System nimmt die gegenseitige Löslichkeit von Wasser und Öl bei einer mittleren Temperatur in der Nähe der Temperatur der Phasenumkehrung erheblich zu. Dieser Bereich erscheint im Zustandsdiagramm als ein schmales und transparentes Gebiet, welches als eine Mikroemulsion angesehen wird. Die elektrische Leitfähigkeit, die Viskosität und der Typ des Fließverhaltens des ternären Systems verändern sich je nach der Temperatur entsprechend einer Veränderung der Struktur des Systems. Rheogramme der ternären Systeme zeigen verschiedene Typen des Fließverhaltens, wie Newtonscher Fluß, pseudoplastischer Fluß, thixotropische Hysterese, dilatantische Hysterese. Die differentialkalorimetrische Analyse zeigte endotherme Effekte bei den entsprechenden Phasenumwandlungen.相似文献
724.
Hirobumi Ushijima Susumu Sudoh Masatsugu Kajitani Kunio Shimizu Takeo Akiyama Akira Sugimori 《应用有机金属化学》1991,5(4):221-228
Four novel cobalt(III) complexes with a cyclopentadienyl or pentamethylcyclopentadienyl ring and dmit or dmio ligands were synthesized, and their electrochemical behaviour was investigated. All these complexes exhibited three one-electron transfer steps: one reduction and two oxidation steps. In addition, a novel organosulphur compound was afforded by electrochemical oxidation of dmit cobalt complex. Thus, these complexes may have considerable synthetic potential as precursors for electron reservoirs and organosulphur compounds. 相似文献
725.
An Hadamard 3-design involving an Hadamard tournament of Szekeres type involves and Hadamard tournament which is not equivalent with an Hadamard tournament of Szekeres type. 相似文献
726.
[reaction: see text] C-1027, an extremely potent antitumor agent, is composed of chromophore 1 and an apoprotein. Here we report a general and efficient route to the exceedingly reactive bicyclo[7.3.0]dodecatrienediyne core of 1, utilizing selenoxide elimination and epoxide deoxygenation to build the cyclopentadiene and enediyne structures, respectively. 相似文献
727.
728.
Here we investigate the kinetics of water-assisted CVD (henceforth denoted as supergrowth CVD) by a quantitative time-evolution analysis based on a simple growth model. We found that the supergrowth can be well described by a model where the dynamics of the catalyst activity is treated similar to radioactive decay. An in-depth analysis based on this growth model revealed the kinetics of the supergrowth CVD, showing a scale relationship between the carbon source and water, and elucidated the role of water as a catalyst activity enhancer and preserver. 相似文献
729.
Chiral amides derived from O-methyl mandelic acid and achiral amines underwent enantioselective alpha-methylation on treatment with LTMP followed by addition of methyl iodide; chirality transfer from an undeprotonated chiral amide into an achiral enolate in a mixed aggregate is supposed to be responsible for the asymmetric induction. 相似文献
730.
The specific heat of typical relaxors, Pb(Mg(1/3)Nb(2/3))O3 (PMN) and Pb(Mg(1/3)Ta(2/3))O3 (PMT), was measured by adiabatic and relaxation methods between 2 and 420 K. A broad anomaly was found in the specific heat curve over the wide temperature range between 150 and 500 K for PMN, and between 50 and 400 K for PMT, which provides evidence for the formation of ferroelectric nanoregions (FNR) in the paraelectric matrix. The entropy of the anomaly was estimated as 3.3 J K(-1) mol(-1) and 2.9 J K(-1) mol(-1) for PMN and PMT, respectively, which implies an order-disorder-type mechanism for the formation of FNR. 相似文献