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121.
Mikuláš Blažek 《Zeitschrift fur Physik C Particles and Fields》1986,32(2):309-316
The energy dependent parameter characterizing the leading particle effect allows to restore the scaling in proton-proton and antiproton-proton multiplicity distributions from Serpukhov until highest available CERN \(S \bar ppS\) collider energies. The identification of theoretical second dispersions with the experimental ones represents one of the basic ingredients in the quantum statistical bosonic approach applied in the present contribution. The KNO scaling at the ISR energies as well as the Worblewski relation for the second dispersions at the \(S \bar ppS\) collider energies arise quite naturally; similar phenomena might appear at higher energies too. Some predictions for 2 and 10 TeV cms energies are specified. 相似文献
122.
S. Djurović N. Konjević M. S. Dimitrijević 《Zeitschrift für Physik D Atoms, Molecules and Clusters》1990,16(4):255-260
We report results of a study of the Stark broadening of halogen atom lines from (1 D)n p levels. Wall stabilized arc is used as a plasma source. Electron densities 2.2–3.2×1022 m?3 are determined from the width ofH α line and electron temperature 9300–10000 K from plasma composition data. The agreement with the results of simple semiclassical calculations is within the limits of the estimated errors of both experiment and theory. An explanation for the large discrepancy between theory and experiment detected for three BrI lines is offered. 相似文献
123.
We report measured Stark shifts and widths of neutral flourine and chlorine lines. Wall stabilized arc is used as a plasma source. Electron densities 2–4×1022 m?3 are determined from the width of theH β line and electron temperatures 9500–10 000 K from plasma composition data. Experimental results for FI and ClI Stark widths and FI Stark shifts agree within 10% with semiclassical calculations. ClI Stark shifts are systematically smaller for about 20% than theoretical data with the only exception of the line from multiplet no. 15 where the discrepancy goes up to 49%. Results of investigation of similarities and regularities of Stark widths are in agreement with the study of Wiese and Konjevi?. Comparison of experimental Stark shifts shows certain types of regularities. 相似文献
124.
The subject of this report is the determination of lysophospholipids; lysophosphatidylcholine, lysophosphatidylethanolamine, lysophosphatidylserine and lysophosphatidic acid, by matrix-assisted laser desorption/ionisation time-of-flight mass spectrometry (MALDI-TOF MS). The mean signal-to-noise ratio (S/N) was used for the first time as a measure of lysophospholipid concentration. Two different sample preparation procedures were applied, the 'standard' procedure and the 'premix' in order to check to what extent these methods influence the results of the lysophospholipid quantification. Results can be summarised as follows: (a) All classes of lysophospholipids can be easily and sensitively analysed by MALDI-TOF MS. The smallest detectable amount of lysophospholipids was 0.09 pmol on the sample plate. That is about two orders of magnitude lower than the amount detectable by standard chromatographic methods. (b) The mean S/N of all peaks detected in the positive ion mass spectra can be used as a measure of the lysophospholipid concentration. Whereas the S/N for neutral lysophospholipids correlated with the applied concentrations only when the samples were analysed as 'premix', the sample preparation and application procedure did not influence the quantification of acidic lysophospholipids. The standard deviations were not higher than 10% of the mean value. (c) All spectra were additionally analysed in the presence of CsCl. The addition of caesium ions makes the peak identification unambiguous in phospholipid mixtures, but the Cs adducts of lysophospholipids do not properly reflect their concentration and, therefore, they were not useful for quantification. (d) The applicability of the method was demonstrated on the organic extract of human neutrophils. 相似文献
125.
A systematic study for the optimization and implementation of high-performance capillary electrophoresis (HPCE) in conjunction with negative ion electrospray ionization-quadrupole time of flight-tandem mass spectrometry (ESI-QTOF-MS/MS) for the analysis of complex glycolipids is described. The performance of the capillary electrophoresis (CE) and off-line CE/ESI-QTOF-MS approach has been explored for screening a complex ganglioside mixture from bovine brain. All instrumental and solution parameters demonstrated to require special adjustment and to have the most substantial effect on the CE separation, abundance of product ions produced in a low-energy collision-induced dissociation (CID) process and their detection by MS/MS, when attempting to identify and sequence single ganglioside molecular species from CE eluted fractions. Upon optimization of the experimental parameters, an efficient methodology emerged providing the general basic requirements for combined CE/ESI-MS analysis of this type of complex glycoconjugate. 相似文献
126.
Summary From studies of aqueous solutions of dodecylammoniumnitrate an association mechanism has been proposed involving multiequilibrium. In the concentration range considered we can differentiate between two aspects: ranges of marked qualitative and quantitative changes and formation of differently structured surfactant species.
Zusammenfassung Aus der Untersuchung wäßriger Lösungen von Dodecylammoniumnitrat würde ein Assoziationsmechanismus abgeleitet, welcher ein Multiequilibrium beinhaltet. Im untersuchten Konzentrationsbereich können zwei Bereiche unterschieden werden: Bereiche mit ausgeprägten qualitativen und quantitativen Änderungen und Bereiche mit der Bildung von verschieden strukturierten oberflächenaktiven Spezies.相似文献
127.
J. Brandštetr 《Journal of Thermal Analysis and Calorimetry》1981,21(2):357-365
A review of instruments for thermochemical (thermometric) solution analysis is given, including new types of isoperibol reaction of bomb calorimeters, the design of which can influence the future development of thermochemical measuring techniques. The new type of Dithermanal (Vaskut-EMG, Hungary, and Herrmann- Morris, France) controls the individual steps of the thermochemical analysis, adding memory and computing capabilities. Similar programming units with microprocessors for bomb and/or reaction calorimetry have been developed by Parr Comp. and Leco Comp. (USA). The latest modification of the Technicon flow analyzer permits on-line analysis of solid samples. For thermochemical titrations, the Sanda titrator (USA) and Vaskut automatic titrator (Hungary) are available. In the USA, the Tronac isothermal or isoperibol calorimeters are widely used. At the Technical University of Brno, ?SSR, smaller table instruments with a water-bath are applied for different modes of solution thermochemical analysis, and also for the reactions of solid samples in liquids. For the measurement of very small temperature differences, PTC thermistors are used. The possibilities of the future development of measuring techniques are outlined. 相似文献
128.
Zusammenfassung Die Temperaturabhängigkeit der Viskosität im System LiNO3–H2O und im Temperaturbereich 20–70°C wird in der Gleichung =A expB/T=T
0 zusammengefaßt; aus der so erhaltenen Beziehung werden Rückschlüsse auf die Struktur der Lösungen gezogen.
Temperature dependence of the viscosity in the system LiNO3–H2O is expressed by =A expB/T-T 0 in the temperature range 20–70°C. Possible relations to structural changes in the solutions are considered.相似文献
129.
Nataša Bukovec 《Thermochimica Acta》1985,96(2):391-395
The thermal decomposition of N2H5Nd(SO4)2·H2O has been studied by simultaneous TG and DSC and by isothermal weight change determination. The final product and the intermediate phases have been identified by chemical analysis, X-ray powder patterns and infrared spectroscopy. The solid phases in the decomposition sequence are: N2H5Nd(SO4)2· H2O → N2H5Nd(SO4)2 → NH4Nd(SO4)2 → Nd2(SO4)3. The reactions overlap under dynamicconditions, isothermally, however, NH4Nd(SO4)2 can be obtained by 200°C. 相似文献
130.
Summary Typical precipitation curves of various metal phosphates have been obtained using the turbidimetric technique. The following
systems have been investigated: Al(NO3)3-K3PO4, Al(NO3)3-KH2PO4, Al(NO3)3NaH2PO4, FeCl3-K3PO4, FeCl3-(NH4)2HPO4, FeCl3K2HPO4, FeCl3-KH2PO4, FeCl3-NaH2PO4, La(NO3)3K3PO4,La(NO3)3-K2HPO4,La(NO3)3-KH2PO4,La(NO3)3NaH2PO4 and Th(NO3)4-K2HPO4. Typical precipitation curves indicated concentration ranges of phosphate precipitation and of complex solubility.
Supported in part by the U.S. Army Research Office, Contract No. DA-ORD-10. 相似文献
Zusammenfassung Typische F?llungskurven verschiedener Metallphosphate, die mittels Trübungsmessungen erhalten wurden, wurden graphisch dargestellt. Die folgenden Systeme wurden untersucht: Al(NO3)3-K3PO4,Al(NO3)3KH2PO4, Al(NO3)3-NaH2PO4, FeCl3-K3PO4, FeCl3(NH4)2HPO4, FeCl3-K2HPO4, FeCl3-KH2PO4, FeCl3NaH2PO4, La(NO3)3-K3PO4, La(NO3)3-K2HPO4, La(NO3)3-KH2PO4, La(NO3)3-NaH2PO4 und Th(NO3)4K2HPO4. Typische F?llungskurven zeigten Konzentrationsgebiete, in welchen die Metallphosphate gef?llt werden, sowie Konzentrationen, die zur Komplexbildung führten.
Supported in part by the U.S. Army Research Office, Contract No. DA-ORD-10. 相似文献