Showing papers by "University of Erlangen-Nuremberg published in 1972"
TL;DR: The NMR shift reagent technique as mentioned in this paper has been introduced to NMR spectroscopy, which is much less expensive but nevertheless useful, and has been applied in a variety of applications.
Abstract: The number of possible applications of NMR spectroscopy has rapidly increased during the past few years. New fields of applications have been opened by the development of supraconducting solenoids and various spin-decoupling techniques and by the method of “pulsed Fourier transform NMR-spectroscopy”. These methods originate mainly from progress in instrumentation. Recently, another “technique” has been introduced into NMR spectroscopy, which—principally on the basis of chemical and spectroscopic experience—is much less expensive but nevertheless useful. The basic principles, background, and most important applications of this method, known as the “NMR-shift-reagent technique”, form the subject of this paper.
107 citations
TL;DR: In this article, the authors investigated the thermoluminescence of Li-doped ZnO single crystals in the temperature range 4.2-300 K and found that a glow curve was observed with three maxima, two emitting the strong polarized yellow luminescence.
103 citations
TL;DR: In this paper, large single crystals of ZnO (up to 20 g weight) have been grown by oxidation of zn-vapour, which contained foreign impurities in a concentration of about 1-3 ppm.
98 citations
TL;DR: In this paper, the surface Debye temperature of a LiF crystal was derived from measurements of the specularly reflected intensity of a thermal beam of atomic hydrogen impinging on the surface of the crystal.
94 citations
TL;DR: The NMR-Spektroskopie is eine nicht minder nutzliche, doch weitaus weniger kostspielige "technik" bereichert worden, die hauptsachlich auf chemischen and spektros-kopischen Erfahrungen beruht as discussed by the authors.
Abstract: Die Zahl der Anwendungsmoglichkeiten der NMR-Spektroskopie ist in den letzten Jahren stark gewachsen. Durch die Einfuhrung supraleitender Elektromagnete, der verschiedenen Verfahren der Kernspin-Entkoppelung sowie der „gepulsten Fourier-Transform”-NMR-Spektroskopie sind neue Anwendungsbereiche erschlossen worden. Wahrend dies vor allem Fortschritte auf apparativem Gebiet waren, ist die NMR-Spektroskopie in letzter Zeit um eine nicht minder nutzliche, doch weitaus weniger kostspielige „Technik” bereichert worden, die hauptsachlich auf chemischen und spektroskopischen Erfahrungen beruht. Der vorliegende Aufsatz befast sich mit dem Prinzip, den Grundlagen und den wichtigsten Anwendungsmoglichkeiten dieser als „NMR-Verschiebungsreagens-Technik” bekannt gewordenen Methode.
89 citations
TL;DR: In this paper, an apparent $1s$-to-2p$ transition was observed with far-infrared spectrometers at 5.9 and 7.2 meV.
Abstract: Apparent $1s$-to-$2p$ transitions, observed with far-infrared spectrometers at 5.9 and 7.2 meV, exhibit linear Zeeman splitting but are not otherwise consistent with the effective-mass hydrogenic model because the activation energy is an order of magnitude too small and the quadratic Zeeman shift is absent. Cyclotron resonance was observed at 5 K but not at 1.3 K, which confirms the existence of shallow bound states.
60 citations
TL;DR: In this article, the shape of well resolved spectral lines for emission, absorption, and scattering phenomena in gases is studied by a kinetic-equation approach, and a spectral function is derived which reduces to a Doppler profile and collision-broadened lorentzian line at low and high densities, respectively, and describes the Dicke narrowing phenomenon at intermediate densities.
58 citations
TL;DR: In this paper, a thermal beam of atomic hydrogen is scattered from the (001) cleavage plane of a LiF crystal and the ( ± 1, 0) diffraction peaks are observed.
55 citations
01 May 1972
TL;DR: The 57Fe Mossbauer effect in [Fe(mephen)3]-BPh4)2(I) and Fe(mepshen3]-I2(II) has been studied between 298 and 4.2°K.
Abstract: Der 5 7Fe-Mosbauer-Effekt wurde in [Fe(mephen)3](BPh4)2(I) und [Fe(mephen)3]I2(II) zwischen 298 und 4,2°K untersucht (mephen = 2-Methyl-1,10-phenanthrolin). Verbindung I zeigt bei 298°K ein fur einen 5 T2-Grundzustand charakteristisches Dublett mit Δ EQ(2 T2) = 0,96mm sec-1 und δIS (5 T2) = +0,96mm sec-1 . Ab 223°K beobachtet man das Auftreten eines zweiten, fur einen 1 A1-Grundzustand charakteristischen Dubletts, dessen Intensitat mit fallender Temperatur zunimmt. Bei 4,2°K hat 1A1 eine Intensitat von 75,2% und es ist Δ EQ(1 A1) = 0,61 mm sec-1, δIS 1A1) = +0,42mm sec-1 . Das Verhalten der Verbindung II ist ahnlich, 1 A1 hat bei 4,2°K eine Intensitat entsprechend 37,3%. Aus der Temperaturabhangigkeit von ΔEQ(5 T2) laβt sich die axiale Ligandenfeldaufspaltung zu δ = -440cm-1 fur I sowie II abschatzen. Die Analyse magnetischer Daten zeigt, daβ der 5 T2−1A1-Termabstand ϵ stark von der Temperatur abhangt, ϵ = 98 cm−1 bei 303°K und ϵ = 890 cm−1 bei 83°K fur I mit ahnlichen Werten fur II. In einem auseren Magnetfeld von 40 kG ergibt sich Vzz > 0 fur den 1A1-Grundzustand von I und II. Fur die Natur des beobachteten Uberganges konnen drei Vorstellungen diskutiert werden: 1. reine Boltzmann-Verteilung; 2. „Spin-Gleichgewichte” mit permanent paramagnetischem Anteil; 3. „Umklapp”-Mechanismus. Ein direkter Einflus des Anions auf den 5T2-1A1-Ubergang ist nicht festzustellen.
The 57Fe Mossbauer effect in [Fe(mephen)3](BPh4)2(I) and Fe(mephen)3]I2(II) has been studied between 298 and 4.2 °K (mephen = 2-methyl-1,10-phenanthroline).At 298°K compound I shows a doublet with ΔEQ(5T2)= 0.96mm sec−1 and δ1S(5T2)= +9.6mm sec−1 characteristic of a 5T2 ground state. As the temperature is lowered, a second doublet, typical for a 1A1 ground state, appears at 223°K and its intensity increases with decreasing temperature. At 4.2°K 75.2% of the intensity is due to the 1A1 state, and Δ EQ(1A1) = 0.61 mm sec−1 and δ1S (1A1) = +0.42 mm sec−1. Compound II behaves similarly, the intensity of the 1A1 state at 4.2″K being 37.3%. From the temperature variation of ΔEQ(5T2)the axial ligand field splitting (δ) is estimated to be -440cm−1 in both I and 11. Analysis of the magnetic data for the compounds demonstrates that the 5T2-1A1 energy separation ϵ is strongly temperature dependent. At 303 and 83°K t: has the values 98 and 890cm−1, respectively, for I and similar values for II. In an applied magnetic field of 40 kG, Vzz > 0 for the 1A1 state in both I and II. Three possible explanations are proposed for the observed transition: 1. pure Boltzmann distribution; 2. spin-equilibrium with a contribution of permanently paramagnetic molecules; 3. spin-flip mechanism. No direct influence of the anion on the 5T2-1A1 transition has been observed.
48 citations
TL;DR: Whether in a streptomycindependent mutant of Chlamydomonas reinhardii the association of the sd-gene with the mitochondrion-“genome” is in agreement with the results obtained in this study is discussed.
Abstract: Dreidimensionale, masstabgetreue Modelle, die nach elektronenmikroskopischen Bildern von Serienschnitten konstruiert wurden, zeigen, das in den Zellen vonChlamydomonas reinhardii nur ein geringer Teil der Mitochondrien eine einfache rundliche oder ellipsoidale Form hat. Die meisten Mitochondrien sind langgestreekt und weisen charakteristische Einschnurungen und Verzweigungen auf. Die Einschnurungen sind mitunter so schmal, das es nicht sicher ist, ob der innere Teil der Mitochondrienhulle noch einen einzigen Innenraum umschliest oder ob das betreffende Mitochondrium 2 getrennte Raume enthalt. Durch ihre Verzweigungen konnen die Mitochondrien Gesamtlangen erreichen, die weit groser sind als die jeweiligen Zelldurchmesser. Die verastelte Form der Mitochondrien kann dazu fuhren, das Mitochondrienanschnitte, die in einem Einzelschnitt sogar an entgegengesetzten Zellpolen auftreten, tatsachlich Teile ein- und desselben Mitochondriums sind. Die wirkliche Zahl der Mitochondrien pro Zelle ist infolge dieser besonderen Gestaltung erheblich geringer als man sie aufgrund der Beobachtung von Einzelbildern schatzen wurde. Sie betrug in 2 durch Serienschnitte vollstandig erfasten Zellen (+Gameten) 9 bzw. 14 Mitochondrien. Es wird diskutiert, ob bei einer streptomycinbedurftigen Mutante vonChlamydomonas reinhardii die Zuordnung des sd-Gens zum Mitochondrien-“Genom” in Einklang mit den hier gewonnenen Ergebnissen steht.
43 citations
TL;DR: In gastric ulcer patients the free, bound, and total N-acetylneuraminic acid (NANA) fractions of gastric juice were shown to be reduced significantly as compared to control subjects and during four weeks of treatment with carbenoxolone sodium, NANA contents increased above normal values.
Abstract: In gastric ulcer patients the free, bound, and total N-acetylneuraminic acid (NANA) fractions of gastric juice were shown to be reduced significantly as compared to control subjects. During four weeks of treatment with carbenoxolone sodium, NANA contents increased above normal values. As sialic acids are known to be essential constituents of gastric glycoproteins which serve as a protective coat, it is suggested that the stimulative effect of carbenoxolone on NANA production may contribute to the increased rate of healing of peptic ulcer in patients treated with the drug. In the present study no statistically relevant evidence was obtained of carben-oxolone-induced changes in Alcian blue binding capacity, acid production, peptic activity, or protein content of gastric juice.
TL;DR: The homoallylic rearrangement (A1 ⇋ A2 ⇋ α-deuterierte Verbindung (A3) durch einen ausergewohnlich grosen sekundaren, thermodynamischen Isotopeneffekt was investigated in this paper.
TL;DR: One woman of the third generation with a balanced translocation C 11/D 13 additionally showed a triplo-X constitution, among 10 pregnancies this woman had 5 abortions and 5 children, 2 of them with multiple malformations.
Abstract: In a pedigree with familial C 11/D 13-translocation the chromosomes of 18 persons in 4 generations were analyzed. 8 of them had a normal karyotype, in 8 cases a balanced translocation was found. Totally 7 children with different multiple malformations were observed, 5 of whom had already died at the time of investigation. The other 2 showed an unbalanced translocation C 11/D 13 with partial trisomy for the long arm of chromosome C 11. These children showed the same syndrome (mental retardation, low birth weight, cutis laxa, hypertelorism, broad flat nose, micrognathia with retracted lower lip, heart malformation, ridge dysplasia of dermatoglyphics).
TL;DR: In this article, a modified size effect theory was used to calculate the electrical resistivity of thin films evaporated under high vacuum conditions, and the maximum resistance increase was calculated as a function of film thickness and measuring temperature.
TL;DR: A new technique for the transvenous implantation of a specially designed atrial sensing electrode in combination with a ventricular stimulating electrode and an atrial-controlled pacemaker enables synchronization of atrial with ventricular activity.
Abstract: A new technique for the transvenous implantation of a specially designed atrial sensing electrode is described. In combination with a ventricular stimulating electrode and an atrial-controlled pacemaker, the method enables synchronization of atrial with ventricular activity. The atrial sensing electrode is put into the right atrial appendage through a preshaped radiopaque Teflon applicator catheter. Two hooks on the electrode tip provide for safe and secure anchoring of the electrode tip to trabeculae of the atrial appendage. The technique has been used for synchronous P wave pacing in 12 patients with complete atrioventricular block, most of them suffering from AdamStokes attacks. Three additional patients with sinoatrial block were treated by means of anchored atrial electrodes. Observation periods of up to 39 months showed no dislocation of any of the anchored atrial electrodes, and performance in all patients was faultless.
TL;DR: In this paper, the rate struktureller Chromosomenaberrationen signifikant (p < 0,001) uber den Werten der unbehandelten, gesunden Vergleichspersonen.
Abstract: Bei 32 mit Anticonvulsiva behandelten Epileptikerinnen und ihren in der Schwangerschaft diesen Medikamenten ausgesetzten Kindern im Alter von 0–3 Jahren lag die Rate struktureller Chromosomenaberrationen signifikant (p<0,001) uber den Werten der unbehandelten, gesunden Vergleichspersonen. Da in den meisten Fallen verschiedene Anticonvulsiva gleichzeitig eingenommen worden waren, konnte nicht entschieden werden, ob Unterschiede in der chromosomenaberrationsauslosenden Wirkung zwischen den einzelnen Anticonvulsiva-Praparate-Gruppen bestehen. Zwischen den Werten der Mutter und der jeweiligen Kinder bestand eine signifikante Korrelation. Hinweise auf eine teratogene Wirkung der untersuchten Anticonvulsiva-Praparate ergaben sich nicht. Die Haufigkeit von Aborten, Totgeburten und misgebildeten Kindern war in der vorliegenden Untersuchung nicht erhoht.
01 Jun 1972
TL;DR: In der vorliegenden Arbeit wurde von verschiedenen Verfahren zur ALA-d-Bestimmung im Vollblut die Methode von Bonsignore u. Hernberg aufgegriffen und auf ihre analytische ZuverlAssigkeit hin gepruft as discussed by the authors.
Abstract: In der vorliegenden Arbeit wurde von verschiedenen Verfahren zur ALA-d-Bestimmung im Vollblut die Methode von Bonsignore u. Hernberg aufgegriffen und auf ihre analytische ZuverlAssigkeit hin gepruft. Als Modifikation dieser Methode wird ein Verfahren zur ALA-d-Bestimmung im Capillarblut angegeben.
TL;DR: In this paper, a trypanocidal Diamidine with three rings in two isolated ring systems is synthesized, which are derived of type A of 6- or 5-amidino-2-[4-amidon-phenyl]-thionaphthene or -benzofuran by further variation of the condensed five-membered ring, by insertion of a bridge of one or two atoms between the two ring systems and by variations of the amidino groups.
TL;DR: In this paper, the stability of the above-mentioned carbamoyl carbonyl complexes increases from the penta-to the tetra- to the tri-carbonyl derivatives.
TL;DR: In a correlative study the gastric acid output and cyclic 3′, 5′-adenosinc monophosphate contents of gastric mucosa were determined in rats and with respect to sex no significant differences were obtained.
Abstract: In a correlative study the gastric acid output and cyclic 3′, 5′-adenosinc monophosphate contents of gastric mucosa were determined in rats. With respect to sex no significant differences were obtained. A concomitant diurnal rhythm was demonstrated for both acid output and cyclic AMP contents of gastric mucosa characterized by a peak at midnight and a trough at noon.
TL;DR: The properties of the new compounds are described and their structures are discussed on the basis of IR and mass spectral data as mentioned in this paper, and the corresponding isocyanato complexes have been obtained by the oxidative degradation of the above compounds with I 2.
TL;DR: In this article, the superconducting critical current density Δjc has been measured as a function of fluence and of the external magnetic fieldHa(jc⊥Ha), and the thermal annealing treatment of the defects concerning thejc and induced by irradiation, has been investigated in the temperature region from 200 to 800 °C.
Abstract: Nb3Sn diffusion layers were irradiated with 24 MeV oxygen ions at fluences from 3.2×1013 up to 1.6×1015 cm−2. The enhancement of the superconducting critical current density Δjc has been measured as a function of fluence and of the external magnetic fieldHa(jc⊥Ha). The thermal annealing treatment of the defects concerning thejc and induced by irradiation, has been investigated in the temperature region from 200 to 800 °C. The results are compared with the measurements of irradiation of Nb3Sn with protons and deuterons. The measured data are discussed in connection with size of defects, cluster distance, fluxline distance and pinning-force.
TL;DR: The 57Fe Mossbauer spectrum of [FeL4] (ClO4)2 where L = 1,8-naphthyridine is characterized by ΔEQ-values between 4.26 mm sec−1 at 298°K and 4.54 mm sec −1 at 4.2°K, Vzz>0, and δIS = +1.06 mmsec−1 as mentioned in this paper.
TL;DR: X-irradiation of dilute solutions of LDH5 in phosphate buffer induces, simultaneously with the loss of activity several changes of the protein structure which became obvious by measuring the u.v.-absorption spectrum, the amino-acid composition, and the titrable SH-groups.
Abstract: SummaryX-irradiation of dilute solutions of LDH5 in phosphate buffer induces, simultaneously with the loss of activity several changes of the protein structure which became obvious by measuring the u.v.-absorption spectrum, the amino-acid composition, and the titrable SH-groups. Furthermore the conformational changes cause the occurrence of four components different in molecular size which could be separated by gel-filtration. The results are compared with those obtained in similar experiments with ribonuclease.
TL;DR: In this paper, the vibrational spectra of a series of tris complexes M (bipy) 3 n + n + 2,2'-bipyridyl with formal oxidation numbers of the metal between +III and −I and those of the mono anion bipy − are reported between 4000 and 200 cm −1.
TL;DR: In this article, the results were consistent with a 3 A 2 (ξ 2 η 2 ϵζ) ground state characterized by a zero-field splitting of D = 4.60 cm −1 into an upper ¦ M S =±1> and a lower ¦ 0> level and g = 2.80.
TL;DR: In this article, linkage isomers involving the O-and S-bonded unidentate sulfinate ions were prepared, which are of the type [M(bipy) 2 (RSO 2 ) 2 ] where R = p -toluene and the metal = Fe II, Co II, and Ni II.