showing 36 of ~574560 from 574555 documents
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1972
Der Zerfall des 2,4-sec100Nb
1972
The nuclide100Nb was produced by irradiation of enriched100Mo targets with 14 MeV-neutrons, and its decay properties were investigated employing scintillation and semiconductor spectrometers and coincidence techniques. A half-life of 2.4±0.3 sec and aQ β-value of 5.8±0.2 MeV were found. From 27 gamma-rays, 20 transitions, representing 95% of the observed gamma-ray intensity, could be placed in a decay scheme comprising 10 excited states of100Mo.
Asymmetric linear Ge(Li)Ge(Li) sum-peak coincidence spectrometer
1972
Abstract An asymmetric linear Ge(Li)Ge(Li) sum-peak coincidence spectrometer configuration has been designed and tested. In this system, the ratio of the gains of two detector-amplifier chains is chosen around 1.2 to 1.3, and the pulse amplitudes or addresses due to coincident events are summed. The simple method introduced involving a single run which results in two spectra (separated according to which detector records the larger energy) appears to be quite useful in γγ coincidence and directional correlation measurements, especially in laboratories where no event-by-event data acquisition hardware are available.
A case of severe repeated immunological reactions to intermittent rifampicin treatment
1972
A case is reported in which a 36-year-old patient twice suffered a rapidly-developing severe reaction to intermittent rifampicin therapy. The symptoms were upper abdominal and back pain, nausea and shivering. Acute renal failure, thrombocytopenia, jaundice and haemolytic anaemia also developed. Aetiologically this was due to an immunopathological effect. This case was unusual in that all the previously observed reactions to rifampicin of an immunological aetiology occurred together, resulting in a marked leucocytosis with the presence of immature cells. It appears that the immediate administration of high-dose corticosteroids can favourably influence this condition. We consider that despite…
Der Zerfall des93Sr
1972
The nucleide93Sr was isolated by chemical separation methods after thermal neutron induced fission of235U, and its decay properties were investigated employing scintillation and semiconductor spectrometers and coincidence techniques. A half-life of 7.43±0.03 min and aQβ-value of 4.3±0.2 MeV were found. Out of 74 gamma-rays, 55 transitions, representing 97% of the observed gamma-ray intensity, could be placed in a decay scheme comprising 22 excited states of93Y.
Comparison of various CI treatments for the description of potential curves for the lowest three states of O2
1972
Abstract Various ab initio CI treatments are reported for the 3 Σ − g , 1 Δ g and 1 Σ + g states of O 2 with particular emphasis on the agreement obtained between calculated and experimental results for binding energies and bond distances of these species and also for transition energies between them. The utility of off-center s and p gaussians in describing the bonding process is stressed and the possibility of optimizing the configurations used in the calculations at each internuclear distance is considered.
Новое зкспериментальное подтверждение для ядра8Не
1972
In this work we present the analysis and interpretation of an event, consistent with the production and subsequent decay of the exotic nucleus8He, found in the study of K− interactions with nuclear-emulsion nuclei at different energies.
Hybriden vonParus melanolophus undParus ater im Nepal-Himalaya
1972
Im Dhaulagiri-Gebiet des nepalischen Himalaya wurde eine Zone der Uberlappung (?) und Hybridisierung vonParus melanolophus undParus ater aemodius entdeckt. Das kritische Material (Anhang, Tafel 1) und die okologisch-biologische Situation (Abschnitt 1, 2) werden in ihrer Bedeutung ausfuhrlich diskutiert (Abschnitt 3–5). Nach den bisherigen Kenntnissen ist die Kontaktzone schmal. In ihr tretenaemodius- undmelanolophus-ahnliche, sowie morphologisch von beiden auffallig abweichende, zimtbauchige (Tafel 1: 3, 8) Hybriden auf. Unter Berucksichtigung aller vorhandenen okologisch-biologischen Information wird aus dem morphologischen Befund der Populationen auf das Bestehen partieller Isolationsmech…
Note on the decay of200Au
1972
Gamma and beta rays from the decay of200Au (48.4 min) were studied employing Ge(Li) and plastic detectors in various singles and coincidence arrangements. The intensity of the β-branch to the ground state of200Hg was determined as 79%, and the disintegration energy of200Au to be asQβ=2.26 ± 0.06 MeV. A tentative spin and parity assignment of (1,2)+ is proposed for levels at 1515.2 and 1972.5 keV in 200Hg
Blutdrucktelemetrie beim Menschen mit der Mikrokathetermethode
1972
Es wird eine einfache, risikoarme, den Probanden nicht belastende Methode zur direkten kontinuierlichen blutdruckmessung und telemetrischen Ubertragung beschrieben. An Hand typischer Anwendungsbeispiele last sich zeigen, das mit dieser Methode sowohl die Erfassung rascher Blutdruckanderungen unter verschiedenen Bedingungen, als auch die genaue Registrierung eines „alltaglichen“ 24 Std-Blutdruckprofils moglich ist. Die Methode erscheint geeignet fur grundlagen-bezogene Studien der Blutdruckrhythmik, wie fur klinisch-pharmakologische Untersuchungsreihen. Verglichen mit herkommlichen indirekten Messungen der Liege-und Steh-Blutdrucke konnte sich mit vorliegender Methode eine „neue Dimension“ i…
On screening effects in pair production at intermediate and high energies
1972
The effect of screening in atomic field pair production is calculated in Born approximation without approximation as to energy or angle and compared with the results of previous calculations based on the high energy approximation. The difference between the two calculations is comparable to the errors in recent experiments. The effect of nuclear excitation on the total pair production cross section is also investigated, but is found to be extremely small.
Molekulargewichtsverteilungen bei der rein thermischen Substanzpolymerisation von Styrol
1972
An rein thermisch in Substanz polymerisiertem Styrol wurden an Testfraktionen mittels kombinierter Gelchromatographie und Viskosimetrie die Molekulargewichte bestimmt. Dabei erhalt man die absoluten Molekulargewichte unabhangig von einer in den Praparaten auftretenden Verzweigung. Die Verteilungen selbst wurden gelchromatographisch gemessen. Fur die Breite der Molekulargewichtsverteilungen ergeben sich im Mittel Mw/Mn-Werte von 2,2. Dies entspricht einer Uneinheitlichkeit U = 1,2, die also etwas groser ist, als bei einer ScHuLzverteilung mit Kopplungsgrad 1. Der hohere U-Wert last sich durch die Nichtstationaritat des realen Polymerisationsvorganges und den Verzweigungsmechanismus erklaren.…
Dualit�ten mit zwei Geraden aus absoluten Punkten in projektiven Ebenen
1972
Die Bedeutung der Brennstoffzufuhr für die Körperfunktionen
1972
Eine neue Technik der Bronchospirometrie
1972
Rat proximal tubule D-glucose transport as a function of concentration, flow, and radius
1972
From earlier microperfusion studies ofD-glucose and water reabsorption in the proximal surface nephron of the rat,D-glucose was found to be removed by a saturable carrier and by an apparent coupling with net fluid reabsorption. Equations appropriate to describe this system were developed. They incorporated carrier-mediatedD-glucose transport, net water transport, and water-coupled solute transport. Water reabsorption was assumed to be constant either per unit surface area, or per unit volume of the nephron, and the rate of carrier-transportedD-glucose was assumed constant per unit length, per unit surface area, or per unit volume of the tubule. The possibility thatD-glucose could be reabsor…
Zur Anwendbarkeit des Pi-Systems in der Vaterschaftsbegutachtung
1972
In der vorliegenden Arbeit wird die Brauchbarkeit des Pi-Systems fur die Gutachterpraxis diskutiert. Berucksichtigt man die geringe Ausschluswahrscheinlichkeit (0,05) und die Schwierigkeiten, die sich bei der exakten Bestimmung einiger Phanotypen ergeben, so scheint das Pi-System nur von geringer forensischer Brauchbarkeit zu sein.
The Parasitic Colonization of the Horny Layer in Tinea Versicolor
1972
Observations of vertical sections and of tape strippings of areas infested with tinea versicolor indicate that because of their dimorphic state, these parasites can colonize the horny layer. Mycelial hyphae progress downwards into the intercellular spaces of the horny cells where they feed on nonkeratinous substances and extrude proliferating yeast cells which form clusters in nest-like cavities. The yeast-mycelial conversion gives rise to new mycelial hyphae and the cycle is complete. The parasites are actually lodged in tunnels and nests hollowed out in the horny layer. A dynamic balance between the cycle of the parasites and the renewal rate of the horny layer is responsible for the long…
Die physiologischen Wirkungen erhitzter Fette, insbesondere der Frittierfette
1972
In dem vorliegenden ubersichtsreferat wurde unter Berucksichtigung der Literatur und eigener Untersuchungen zu dem Problem der physiologischen Wirkungen von Frittierfetten Stellung genommen.
The role of target geometry in 14 MeV neutron capture cross-section measurements
1972
Abstract Some activation capture cross sections of 14.5 MeV neutrons have been measured by systematically varying the target geometry. In all cases, the results are found to strongly depend on the geometrical conditions, which implies that a large part of the activation capture cross sections reported earlier are in error. An investigation of a number of materials shows that aluminium gives rise to a fairly small fraction of secondary low-energy neutrons and is, therefore, suitable material for target holders. A thin air-cooled target head specially designed for reliable activation cross-section measurements has been constructed and tested.
D-Glucose and fluid reabsorption in proximal surface tubule of the rat kidney
1972
Hexose reabsorption in the kidney was investigated by microperfusion of proximal cortical rat nephrons with Ringer's solution containingD-glucose (2.5, 5.0 and 18.0 mM/l), 3-O-methylD-glucose (4.5 mM/l) orD-fructose (18.0 mM/l) at perfusion rates of 20 or 40×10−6 ml/min. Inulin was used as a reference for fluid reabsorption. 1. The fraction of fluid reabsorbed was independent of the glucose concentration but it decreased when the perfusion rate increased from 20–40×10−6 ml/min. 2. At 18.0 mM/l the % glucose reabsorption was equal to the % fluid reabsorption. This equality was independent of the perfusion rate, (20 or 40×10−6 ml/min), indicating 1:1 coupling with net isotonic fluid reabsorpt…
Darstellung temperierter vektorwertiger Distributionen durch holomorphe Funktionen I
1972
Die Einführung der sogenanntenv-Koordinate als Variable für die Clearance-Kurven der Lunge zur Berücksichtigung der Variation der Atemfrequenz und de…
1972
Probable collapse mechanisms in indefinite plates on an elastoplastic continuum
1972
With reference to a theory expounded in a previous note [2] on the limit state behaviour of plates resting on an elastoplastic continuum subject to distributed loads, probable collapse mechanisms are considered in order to supplying more tractable solutions for technical practice. As the case is a general one, it is shown that the results obtained are suitable for following the load carrying capacity of plates and the relative collapse mechanism as the limit resistance of the soil and the spread of the load acting on it vary.
Trimethylplatinum(IV) complexes with ON bidentate ligands
1972
Abstract Complexes of the trimethylplatinum(IV) moiety with bidentate monobasic salicylaldimines C 6 H 5 (OH)CHNR (R = ethyl, propyl, phenyl) have been prepared and characterized by IR, UV and NMR spectra and magnetic susceptibility measurements. The complexes are dimeric with double PtOPt bridges, and the metal appears to be pseudo-octahedrally hexacoordinated.
Zum Mechanismus der Inden‐Bildung durch Friedel‐Crafts‐Cycloalkenylierung
1972
α,β-Ungesattigte Aldehyde reagieren mit Benzol unter Friedel-Crafts-Bedingungen zu Indenen. Mittels 14C- und 2H-indizierten Verbindungen werden die reversible, nucleophile Addition von Benzol an Zimtaldehyd sowie die 1.3-Wasserstoff-Verschiebung im Crotonaldehyd beim Ringschlus nachgewiesen. On the Mechanism of the Indene Formation by Friedel-Crafts Cycloalkenylation α,β-Unsaturated aldehydes were condensed with benzene in a Friedel-Crafts type reaction to give indenes. With the aid of 14C- and 2H-labelled compounds both the reversible nucleophilic addition of benzene to cinnamaldehyde and the 1.3-hydrogen shift in the cycloalkenylation of crotonaldehyde are examined.
Über die bildung von ab-blockcopolymeren bei der darstellung von aba-blockcopolymeren
1972
Effects of several muscarinic agonists on cardiac performance and the release of noradrenaline from sympathetic nerves of the perfused rabbit heart
1972
Summary 1 The effects of several muscarinic agonists on atrial tension development, ventricular rate and noradrenaline release from terminal sympathetic fibres evoked by electrical nerve stimulation (SNS) and 1,1-dimethyl-4-phenylpiperazinium (DMPP) were measured in isolated perfused rabbit hearts. 2 Hexamethonium, in a concentration which almost abolished the release of noradrenaline by DMPP, had no effect on the release produced by SNS, confirming that the stimulation was postganglionic. 3 The order of potency for inhibition of atrial tension development was N-methyl-1,2,5,6, tetrahydro-nicotinic acid prop-2-yne ester (MH-1)>oxotremorine > acetylcholine > methacholine > carbachol > furtre…
Friessche verschiebung bei acetylderivaten phenolischer mehrkernverbindungen
1972
Die FRIES sche Verschiebung wurde an den Acetylderivaten einiger phenolischer Zweiund Dreikernverbindungen untersucht. In Nitrobenzol, mit AlCl3 als Katalysator, ist bei Temperaturen von 40-60°C eine gleichzeitige Umlagerung von mehreren Acylgruppen pro Molekul in die para-Stellung zur phenolischen Hydroxylgruppe ohne Schwierigkeiten moglich. Methoxygruppen bleiben dabei erhalten. Die bei hoheren Temperaturen verlaufende Umlagerung in die ortho-Stellung zur phenolischen Hydroxylgruppe gelang jedoch bisher nicht. Die erhaltenen Mehrkernverbindungen mit p-Hydroxyacetophenonbausteinen wurden IR-, UV- und NMR-spektroskopisch untersucht. Sie wurden ferner durch Uberfuhrung in die entsprechenden …
Die Wirkung einiger Cytostatica auf die DNA Synthese in einem oncogenen RNA Virus
1972
Sowohl durch matrizeninaktivierende Cytostatica als auch durch Cytostatica, die am Enzymprotein angreifen, konnen in vitro die RNA-abhangige DNA-Polymerase und die DNA-abhangige DNA-Polymerase aus RML-Viren gehemmt werden. Von den getesteten Cytostatica, die die Matrize inaktivieren, wirken Daunoblastin (=Daunomycin) und Adriamycin selektiv hemmend auf die RNA-abhangige DNA-Polymerase, wahrend Olivomycin, Chromomycin und Actinomycin D bereits in niedrigen Konzentrationen die DNA-abhangige DNA-Polymerase aus RML-Viren selektiv inhibieren. Durch 2 Cytostatica konnen die enzymatischen Reaktionen der DNA-Polymerasen aus RML-Viren, durch Angriff am Enzymprotein beeinflust werden: Demethyl-Rifamp…
Isothermal flow of helium II through plane slits
1972
Measurements are reported on the isothermal, gravitational flow of liquid He II through narrow plane slits. The employed superleak consists of ring-shaped Hostaphan foils packed in layers. The distance between the foils is varied by pressure. The performance of the measurements and the observance of the isothermal conditions are described. The velocity of the superfluid component of He II is calculated in dependence on the width of the slits, the temperature and the hydrostatic pressure. Especially the critical velocity is considered.
Ein iteratives numerisches verfahren zur auswertung von elutionsanalysen an eng verteilten polymeren
1972
Ein iteratives Rechenverfahren zur Bestimmung der Molekulargewichtsverteilungsfunktionen aus experimentellen, mit der isothermen Elution ermittelten Daten – speziell fur Polymere kleiner Uneinheitlichkeit – wird beschrieben. Hierbei wird die klassisch gewonnene Verteilung als Naherung betrachtet, rechnerisch auf der Basis des Phasengleichgewichts erneut fraktioniert und aus den ermittelten Fraktionen die Zusatzinformation zur Konstruktion einer besseren Naherung gewonnen. Um die Stabilitat der Konvergenz des Verfahrens zu zeigen, wurde eine Simulationsrechnung durchgefuhrt. Schlieslich wird das Verfahren an experimentell gewonnenen Daten eines aus zwei gut bekannten, eng verteilten Polystyr…
p-Di-(1-phenylvinyl)-Benzol und seine reaktion mit elektronenüberträgern
1972
p-Di-(1-phenylvinyl)-benzol (I) wurde, ausgehend von p-Diacetylbenzol und Phenylmagnesiumbromid, in hoher Reinheit und guter Ausbeute dargestellt und charakterisiert. I setzt sich spontan mit Elektronenubertragern (Natrium, Naphthalin-Natrium) unter Ausbildung einer tief violetten Farbung um. Es entstehen die Oligomeren bis zum Dekameren, wobei die geradzahligen Homologen in hoherer Konzentration vorliegen als die jeweils benachbarten ungeradzahligen. Die Ergebnisse werden diskutiert. p-Di-(1-phenylvinyl) benzene (I) was prepared from diacetyl benzene and phenyl magnesium bromide in high purity and with good yield. It was identified by IR, NMR, and elemental analysis. I reacts immediately w…
The decomposition of 1-phenyl-3-chloro-nortricyclene and 1-phenylnortricyclene on reduction in 1,2-dimethoxyethane. The EPR spectra of the radical io…
1972
Radical anions of 1-phenyl-3-chloronortricyclene and 1-phenylnortricyclene were produced by reduction with potassium in 1,2-dimethoxyethane under a high vacuum. The initially formed radical anion of 1-phenyl-3-chloronortricyclene was very unstable, and decomposed finally to the anions of naphthalene and biphenyl. The only product of the reduction of 1-phenylnortricyclene was the biphenyl anion. The EPR spectra of the reaction mixtures were measured at temperatures from —80°C to room temperature.
Über die oligomerisierung von Cycloocten
1972
Cycloocten wurde in Anwesenheit des Katalysatorsystems WCl6/C2H5OH/C2H5AlCl2 oligomerisiert mit dem Ziel, die homologe Reihe (C8H14)n darzustellen. Es wurden die Reaktionsbedingungen, besonders hinsichtlich der Katalysator-Konzentration, und der Einflus des Losungsmittels untersucht. Die isolierten Oligomeren (Dimeres, Trimeres) wurden IR-, NMR- und massenspektrometrisch charakterisiert. Cyclooctene was oligomerized in the presence of the catalytic system WCl6/C2H5OH/C2H5AlCl2 in order to prepare the homologous series (C8H14)n. The conditions of reaction were established particularly with respect to the catalyst concentration. The influence of the solvent was investigated. The oligomers pre…