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31.
V. V. Aivazyan I. V. Ajinenko Yu. A. Belokopytov P. C. Bosetti H. B?ttcher F. Botterweck P. V. Chliapnikov F. Crijns A. De Roeck E. A. De Wolf Th. Driever K. Dziunikowska A. Eskreys W. Friebel Z. C. Garutchava V. G. Gavrjusev H. Graessler P. van Hal T. Haupt W. Kittel S. S. Megrabyan F. Meijers A. B. Micha?owska V. I. Nikolaenko L. C. S. Oliveira K. Olkiewicz L. P. Petrovikh E. Riipinen V. M. Ronjin A. M. Rybin H. M. T. Saarikko W. Schmitz L. Scholten R. Schulte O. G. Tchikilev L. A. Tikhonova A. G. Tomaradze V. A. Uvarov F. Verbeure R. Wischnewski A. Wróblewski S. A. Zotkin NA Collaboration 《Zeitschrift fur Physik C Particles and Fields》1989,42(4):533-542
Forward-backward multiplicity correlations in σ+,K + p andpp collisions at 250 GeV/c ( \(\sqrt s \) =22 GeV) are given for all charges and for the different charge combinations. The correlations are found to be caused predominantly by centrally produced particles. It is demonstrated that this result is an agreement with observations at the ISR and the CERNp \(\bar p\) -Collider. The results are compared to expectations from LUND, DPM and FRITIOF Monte Carlo models and a geometrical picture relating correlations in hadron-hadron collisions toe + e ? data in terms of impact parameters is tested. 相似文献
32.
Małgorzata Borówko Jacek Goworek Mieczysław Jaroniec 《Monatshefte für Chemie / Chemical Monthly》1982,113(6-7):669-680
A model of monolayer adsorption of binary liquid mixtures on homogeneous and heterogeneous solid surfaces involving association of one component in the bulk phase is discussed. Suitable model calculations, illustrating association and heterogeneity effects, have been performed according to an equation derived for adsorption excess. This equation has been examined by using the experimental data of adsorption of alcohols from benzene andn-heptane on silica gel.
Adsorptionsmodell für die Grenzfläche Feststoff-Flüssigkeit unter Berücksichtigung der Assoziation in der Flüssigkeitsphase
Zusammenfassung Es wird ein Adsorptionsmodell binärer, flüssiger Mischungen an homogenen und heterogenen Oberflächen von Feststoffen unter Beachtung der Assoziation eines der Bestandteile in der Flüssigkeitsphase diskutiert. Mit der aus dem Oberflächenüberschuß abgeleiteten Gleichung wurden entsprechende Modellberechnungen durchgeführt, die die mit Assoziation und Heterogenität verbundenen Effekte illustrieren. Die Gleichung wurde für die experimentellen Daten der Alkoholadsorption aus Benzol undn-Heptan an Kieselgel überprüft.相似文献
33.
The DTA method was used to determine the phase diagram of the NaCl-CaSO4 system over the range 0.55 wt.% of CaSO4 in air atmosphere. The effects of SiO2, CaCO3 and Fe2O3 on the melting temperatures of pure NaCl and the eutectic were determined. On the basis of the above temperatures, a method of quantitative determination of the anhydrite content in rock salts has been developed.
Zusammenfassung DTA wurde benutzt, um in Luft im Bereich 0 bis 55,0 Gew.% CaSO4 das Phasendiagramm des Systemes NaCl-CaSO4 zu bestimmen. Es wurde auch der Einfluß von SiO2, CaCO3 und Fe2O3 auf die Schmelztemperatur von reinem NaCl bzw. des Eutektikums bestimmt. Auf der Grundlage obiger Temperaturen wurde eine Methode zur quantitativen Bestimmung des Anhydritgehaltes in Steinsalzen entwickelt.
- 0–55,0 . , . , ( ) .相似文献
34.
The dissociation constants of diprotonated 3,3'-dimethylnaphthidine (DMN) and 3,3'-dimethoxybenzidine (DMB) have been determined spectrophotometrically. They are: pK(a1) = 2.62 +/- 0.03, pK(a2) = 3.33 +/- 0.09 for DMN: pK(a1) = 2.83 +/- 0.07, pK(a2) = 4.05 +/- 0.12 for DMB. The molar absorptivities (l.mole(-1).cm(-1)) of all forms of the indicators have been also determined: epsilon(B) = 1.68 x 10(4), epsilon(BH(+)) = 9.34 x 10(3), epsilon(BH(2+)(2)) = 1.80 x 10(3) at 300 nm for DMB; epsilon(B) = 7.33 x 10(3), epsilon(BH(+)) = 3.73 x 10(3), epsilon(BH(2+)(2)) = 0 at 330 nm for DMN. 相似文献
35.
36.
Kučinskaitė Agnė Pobłocka-Olech Loretta Krauze-Baranowska Mirosława Briedis Vitalis Savickas Aruñas Sznitowska Małgorzata 《平面色谱法杂志一现代薄层色谱法》2007,20(2):121-125
SPE and TLC have been used for qualitative and quantitative analysis of salidroside, rosavin, rosarin, and rosin in commercially available dry extracts from Rhodiola rosea roots. The best separation of all the compounds was achieved on silica gel TLC plates with ethyl acetate—methanol—water, 77 + 13 + 10 (v/v), as mobile phase. UV detection was performed at λ = 215 nm for salidroside and at λ= 245 nm for the rosavins (rosavin, rosarin, and rosin). Detection limits for salidroside and the rosavins were 90 ng and 60 ng per spot, respectively. Results from quantitative analysis confirmed the manufacturer’s declaration of the amounts of salidroside and the rosavins in the extracts.
相似文献37.
Cl···O intramolecular contacts are analysed here. Hence the Cambridge Structural Database (CSD) search was performed to find
five-membered Cl–C=C–C=O pseudo-rings closed through Cl···O intramolecular contacts. Such rings were analysed and it was found
that some of Cl···O distances are smaller than the corresponding sum of van der Waals radii. Additionally ab initio MP2/6-311++G(d,p)
calculations and AIM analyses were carried out here on 3-chloropropenal and its fluoro derivatives to deepen the nature of
intramolecular Cl···O interactions, some of findings may indicate that they are attractive and stabilizing ones.
This paper is dedicated to Prof. T. M. Krygowski on the occasion of his 70th birthday 相似文献
38.
The solvation force of a simple fluid confined between identical planar walls is studied in two model systems with short ranged fluid-fluid interactions and long-ranged wall-fluid potentials decaying as -Az(-p),z--> infinity, for various values of p. Results for the Ising spins system are obtained in two dimensions at vanishing bulk magnetic field h=0 by means of the density-matrix renormalization-group method; results for the truncated Lennard-Jones (LJ) fluid are obtained within the nonlocal density functional theory. At low temperatures the solvation force f(solv) for the Ising film is repulsive and decays for large wall separations L in the same fashion as the boundary field f(solv) approximately L(-p), whereas for temperatures larger than the bulk critical temperature f(solv) is attractive and the asymptotic decay is f(solv) approximately L(-(p+1)). For the LJ fluid system f(solv) is always repulsive away from the critical region and decays for large L with the the same power law as the wall-fluid potential. We discuss the influence of the critical Casimir effect and of capillary condensation on the behavior of the solvation force. 相似文献
39.
Maria Nowakowska Mirosława Smoluch Dorota Sendor 《Journal of inclusion phenomena and macrocyclic chemistry》2001,40(3):213-219
The effect of -, - and -cyclodextrin onthe photochemical stability of 7-amino-4-methylcoumarin (C120)was studied. Using spectroscopic techniques (UV/Vis absorption spectroscopy, fluorescence, fluorescence anisotropy and circular dichroism) combined with HPLC/MS and MS analysis it was demonstrated that addition of -cyclodextrin to the aqueoussolution of C120 markedly inhibits the photodegradation of that dye. This results from theformation of an inclusion complex between C120 and -cyclodextrin. 相似文献
40.