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1.
Experimental Investigations of Ionisation and Charge-transfer of Alcohols by 6-25 keV Hydrogen Ions Ionisation and charge-transfer cross sections were measured for the interaction of H+, H and H ions (in the energy range 6-25 keV) with alcohols (methanol-octanol). The cross sections depend significantly on the target molecular structure like molecular length, ionisation potential, polarizability and atomic bonds in the target molecule.  相似文献   

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The radiation excited in nitrogen and hydrogen by an electron swarm moving in a uniform electric field is investigated. In nitrogen the bands of the 2 nd positive group in the region from 3400 to 3800 Å are the dominating part of the radiation. In hydrogen the main part of the radiation is lying in the far ultraviolet (1000 to 1200 Å) due to the excitation of the state 21 II u . The coefficientδ describing the intensity of the radiation is measured with a photomultiplier device as a function of the electric fieldE and the pressurep in the range from about 10 to 100 Torr. Besides the dependence ofδ onE/p a pressure dependence is found which is explained as a quenching process of the excited molecules by collisions. The pressurep 0 for equal probability of radiating and non-radiating decay of the states involved is 60 Torr in N2 and 20 Torr in H2. The theoretical interpretation of the dependence onE/p supports the excitation energy of the state C3 II u of N2 for electron impact to be equal to the spectroscopical value of 11·04 eV and yields 0·9·10?16 cm2 for the maximum of the excitation cross section. The results of the measurements in H2 can be described assuming a cross section of 0·55·10?16 cm2 for the excitation of the state 21 II u by electron impact.  相似文献   

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Die grundlegenden Gedanken über die Nutzung chemisch-kinetischer Isotopieeffekte des Wasserstoffs zur Erhöhung der Beständigkeit chemischer und pharmazeutischer Erzeugnisse gegenüber diese Stoffe schädigenden Vorgängen wie Autoxydation, Oxydation, Hydrolyse u. a. werden dargelegt. Die ökonomischen und technischen Vorteile dieser Methode werden am Beispiel der Deuterierung eines Uhrenöls demonstriert.  相似文献   

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Es wurden folgende isotopisomere Formen des Bernsteinsäuredibenzylesters synthetisiert:

C6H5CH2–OOCCH2CH2COO–CH2C6H5, (I)

C6H5CD2-OOCCH2CH2COO–CD2C6H5, (II)

C6H5CH2–OOCCD2CD2COO7ndash;CH2C6H5, (III)

C6H5CD2-OOCCD2CD2COO–CD2C6H5. (IV)

Die Gesehwindigkeit der Autoxydation dieser Verbindungen bei 191 °C zeigt Isotopieeffekte der Größe k1/k11 = 4,3 ± 0,5; k1/k111 = 1,0 und k1/kiv = 4,6 ± 0,5, bezogen auf die Maximalgeschwindigkeit. Durch die Anwesenheit des Inhibitors Phenyl-a-naphthylamin (0,1%) werden die maximalen Geschwindigkeiten der Autoxydation nicht beeinflußt. Die Induktionsperioden werden hingegen bei den Verbindungen (I) und (II) in sehr unterschiedlicher Weise verändert, so daß die Induktionsperiode von (II) 40mal länger als die von (I) wild.  相似文献   

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Zeitschrift für Physik A Hadrons and nuclei - Es werden Lichtanregungsversuche durch Caesiumionenstoß in leichtem und schwerem Wasserstoff beschrieben. Für einige Wasserstoff- und...  相似文献   

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Short light sparks release 10 nsec pulses of 105 electrons each which initiate electron avalanches in high-purity argon and hydrogen. The transit times of the avalanches are measured and thus the drift velocities of ions and electrons derived. — There is general agreement with available results of other authors.  相似文献   

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This paper describes the measurement of ionization and charge exchange cross-sections for hydrogen atoms (H0), Protons (H+) and molecular hydrogen ions H 2 + and H 3 + in hydrogen gas in the energy range 9 to 60 keV. Further, the emission of secondary electrons from copper-beryllium by impact of these particles was measured. A beam of monoenergetic neutral hydrogen atoms was produced by charge exchange of a beam of protons in a gas chamber. Separation of the charged and uncharged components was accomplished by a magnetic field. The pressure in the chamber in which the cross-sections were measured was so low, that only a few particles of the incident beam suffered an effective collision. The positive and negative charges, which were produced by ionization and charge exchange along the path of the beam, were extracted by a transverse electric field and the saturation current was measured. The intensity of the neutral beam was determined at the same time by repeated charge exchange in an 80 mμ thick foil of aluminiumoxide.  相似文献   

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In der Abteilung fūr Isotopentrennung des Instituts für Atomphysik Cluj wurde eine kontinuierlich arbeitende Abreicherungskolonne für die Gewinnung von an Deuterium verarmtem Wasser entwickelt. Es wurde zur Herstellung von Standardproben mit Deuteriumkonzentrationen unterhalb der natūrlichen Isotopenzusammensetzung in größeren Mengen benötigt.  相似文献   

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Using a Cf252-fission source and two semiconductor detectors in 180°-position the specific energy loss of heavy ions in A1-, Ag-, and Au-foils was measured. The agreement with the results ofMoak andBrown, and ofKahn andForgue is better than 15%. The energy loss predicted byLindhard is 10–25% lower than the measured values. A better agreement — especially for absorbers with low atomic numberZ — is achieved by a semiempirical formula proposed byMünzel.  相似文献   

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