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1.
Summary AT-x phase diagram of the system sodium stearate (NaSt)-stearic acid (HSt) has been determined by DTA. It shows the existence
of five defined association compounds, three of them (2 NaSt · 3 HSt, NaSt · HSt and 3 NaSt · 2 HSt) with an incongruent melting
point and the others (5 NaSt · 2 HSt and 5 NaSt · HSt) with a congruent melting point. The latter two compounds pass through
various mesomorphic phases before melting.
The components do not form solid solutions and are even non-miscible in the mesomorphic state below 200 °C. Mutual miscibility
is only observed above this temperature in the subneat and neat region, occurring in the HSt composition range from 0 to 15
and from 0 to 5 mole% respectively.
The existence of molecular associations in the liquid state is very probable, particularly in the composition range between
30 and 40 mole% stearic acid. This might result in a liquid structure similar to that present in the melt of anhydrous soaps.
Zusammenfassung EinT-x Zustandsdiagramm des Natriumstearat (NaSt)- Stearins?ure (HSt)-Systems wurde mittels DTA bestimmt. Es weist fünf definierte assoziierte Verbindungen auf, drei (2 NaSt · 3 HSt, NaSt · HSt und 3 NaSt · 2 HSt) mit einem inkongruenten Schmelzpunkt und zwei (5 NaSt · 2 HSt und 5 NaSt · HSt) mit einem kongruenten Schmelzpunkt. Die zwei letzteren Verbindungen durchlaufen verschiedene mesomorphe Phasen, bevor sie schmelzen. Die Komponenten bilden keine festen L?sungen und sind im mesomorphen Zustand unter 200 °C nicht einmal miteinander mischbar. Nur bei h?heren Temperaturen sind sie v?llig mischbar, und zwar in der “subneat” und “neat” Region, die im HSt-Bereich von 0 bis 15 bzw. von 0 bis 5 Mol% reicht. Die Existenz molekularer Assoziate im flüssigen Zustand ist sehr wahrscheinlich, vor allem im Bereich zwischen 30 und 40 Mol% Stearins?ure. Dies k?nnte zur Bildung von Strukturen in der Flüssigkeit führen ?hnlich, wie dies bei der Schmelze wasserfreier Seifen der Fall ist.相似文献
2.
Zusammenfassung Es werden die Absorptionsspektren von sechs Derivaten des 1,8-Naphthyridins und ihre Abhängigkeit vom pH-Wert des Lösungsmittels besprochen. Die vermutlichen Gründe hierfür werden diskutiert. Weiters wird auf Zusammenhänge mit den Spektren des Naphthalins und Chinolins hingewiesen.Mit 7 Abbildungen 相似文献
3.
Uwe Klingebiel Detlev Enterling Lutz Skoda Anton Meller 《Journal of organometallic chemistry》1977,135(2):167-172
Fluorosilyl substituted cyclosilazanes are formed by treating lithium salts of hexamethylcyclotri- and octa-methylcyclotetrasilazanes with silicon tetrafluoride and organo-substituted silicon fluorides. Disubstituted compounds are obtained by the reaction of dilithium hexamethylcyclotrisilazane with silicon fluorides or by the reaction of lithium hexamethylcyclotrisilazane with silicon fluorides at higher temperature. Cyclosilazanes with bulky ligands react with butyllithium with elimination of butane as a first step and then react further with a silicon fluoride compound, with LiF-elimination, to give a mixed substituted cyclosilazane. Ring coupling through a silicon bridge is achieved by the reaction of a fluorosilyl-substituted cyclotrisilazane with lithium hexamethylcyclotrisilazane. The mass,1H and19F NMR spectra of the compounds are reported. 相似文献
4.
Petr Munster Tomas Horvath Josef Vojtech Ondrej Havlis Martin Slapak Pavel Skoda 《Fiber and Integrated Optics》2017,36(3):144-156
Currently, individual optical fibers are mostly used for each non-data application, which is very inefficient and uneconomical. Sharing a single fiber for multiple applications is a promising solution. However, in the case of a non-data application, the situation is much more complicated compared to data because of special application´s requirements. In laboratory setup, we performed a measurement with a standard G.652D optical fiber for analyzing possible interaction of stable frequency/accurate time transmission, 1.25/10Gbps data transmission (typical bitrates for access point-to-point networks), and high-power sensor signal for different channel spacing and different pulse duration of sensor signal. 相似文献
5.
6.
K. Bharuth-Ram J. Billowes J. Heese C. J. Gross K. P. Lieb N. Martin S. Skoda J. Eberth 《Hyperfine Interactions》1990,59(1-4):109-112
The IMPAD technique has been used to determine the Larmor precessions of the83Y 595 keV 13/2+ and 145 keV 7/2+ states in iron. The net precessions found are ωτ(13/2+)=−9(2) mrad and ωτ(7/2+)=−92(5) mrad, leading to g-factors, g(13/2+)=+1.3(4) and g(7/2+)=+0.61(18). These results are discussed in terms of a partially decoupled [422]5/2+ Nilsson band. 相似文献
7.
S. Skoda J. L. Wood J. Eberth J. Busch M. Liebchen T. Mylaeus N. Schmal R. Sefzig W. Teichert M. Wiosna 《Zeitschrift für Physik A Hadrons and Nuclei》1990,336(4):391-402
Two collective bands of75Kr have been extended up to spin 21/2 using the compound reactions64Zn(14N,p2n)75Kr and50Cr(28Si, 2pn)75Kr. Spins and parities were assigned from neutron-gatedγ-ray angular distributions and excitation functions using the OSIRIS anti-Compton spectrometer. The bands are interpreted to be built on the well-deformed Nilsson states: [442] 5/2 and [301] 3/2. Energies for both bands and the order of magnitude of the mixing ratios in thef 5/2 band can be reproduced within the single-particle-plus-rotor model, while the experimentalQ(I→I?1)/Q(I→I?2) ratios, deduced from mixing ratios and branching ratios, exhibit large deviations by a factor 4 to 6 from theoretical values (which are around one). An explanation of this effect may be found by treating the two rotational bands each as a result of mixing between rotational bands of oblate and prolate states; thus explaining the large difference between B(E2,I→I?1) andB(E2, I →I?2) in the bands of75Kr. 相似文献
8.
T. D. Johnson F. Cristancho C. J. Gross M. Kabadiyski K. P. Lieb D. Rudolph M. Weiszflog T. Burkardt J. Eberth S. Skoda 《Zeitschrift für Physik A Hadrons and Nuclei》1994,347(4):285-286
Doppler shift attenuation lifetime measurements have been carried out for the 3qp and isomeric rotational bands in83Y using the reaction58Ni(28Si,3p). While the transitional quadrupole moments in the 3qp bands are slightly lower than in the 1qp bands, we found evidence for a strong reduction in ¦Qt¦ for the isomeric band. 相似文献
9.
M. K. Kabadiyski F. Cristancho C. J. Gross A. Jungclaus K. P. Lieb D. Rudolph H. Grawe J. Heese K. -H. Maier J. Eberth S. Skoda W. -T. Chou E. K. Warburton 《Zeitschrift für Physik A Hadrons and Nuclei》1992,343(2):165-177
The reaction58Ni(36Ar, 4p)90Mo has been studied at a beam energy of 149 MeV. A detector array consisting of the OSIRIS spectrometer (12 Compton-suppressed Ge detectors), four charged-particleδE detectors and seven NE-213 neutron detectors at the VICKSI accelerator in Berlin has been used to measure the gamma radiation inγγ- and particle-γγ-coincidence mode. An additional Ge detector was placed at 162? to the beam direction to provide information on DCO ratios. The level scheme of90Mo has been extended up to an excitation energy of about 12 MeV and probable spin 23?. Some 70 transitions and 40 levels have been newly identified. Spin assignments have been proposed on the basis of measured DCO ratios. Shell model calculations in a model space consisting of the proton 1f 5/2, 2p 3/2, 2p 1/2, and 1g 9/2 orbits and the neutron 2p 1/2, 1g 9/2, 1g 7/2, 2d 5/2, 2d 3/2, and 3s 1/2 orbits with some truncation were made for states above 9? and the predicted structure of these states is discussed. 相似文献
10.
W. Fieber K. Bharuth-Ram J. Heese F. Cristancho C. J. Gross K. P. Lieb S. Skoda J. Eberth 《Zeitschrift für Physik A Hadrons and Nuclei》1989,332(4):363-370
Deformation parameters of the positive parity yrast band and negative parity bands in83Zr are deduced from lifetimes andE2/M1 mixing ratios. Lifetimes of high spin states have been determined from recoil distance Doppler shift and Doppler shift attenuation measurements using the54Fe(32S,2pnγ) 83Zr reaction. Ten lifetimes and five lifetimes limits were determined. The positive parity band, built on theg 9/2 K=5/2 orbital has an average deformation ¦β 2¦=0.28(2), and shows a reduction ofE2 transition strengths in the observed backbend region at Iπ≈21/2+. In contrast, theE2 strengths in the negative parity states show a steady increase up to Iπ≈=15/2?. These states are more strongly deformed than the positive parity states (¦β 2¦=0.33(3)). TheE2/M1 mixing ratios show that the negative parity band hasK=3/2 and is prolate, and favour oblate deformation for the positive parity yrast band. In theK=1/2? band theE2 strength of the 7/2?→3/2? transition yields a deformation ¦β 2¦=0.26(5). The band structure is compared with calculations within the Hartree-Fock Bogoliubov cranking model. 相似文献