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1980[X]
21Author    RajihaI. Al-Nia 'mi, Muthana ShanshalRequires cookie*
 Title    Konformation konjugierter Cyclopropanderivate mit sterischer Hinderung  
 Abstract    The influence of a-and o-methyl substituents on the conformation of phenylcyclopropane is studied. Synthesis as well as low temperature PMR studies of the corresponding derivatives are carried out. The changes in the PMR spectra measured at room temperature and —100 °C are too small to count for the rotation barrier calculations. Fo 2,2-dichloro-l-phenyl-cyclopropane (8) ,2,2-dichloro-l-methyl-l-phenyl-cyclopropane (9) and 2,2-dichloro-l-o-tolyl-cyclopropane(10) the predicted most stable conformation is the near-bisected in which the aromatic ring is slightly twisted towards the CI atoms. For 2,2-dichloro-l-(2,6-dimethyl-phenyl)-cyclopropane (11) the planar conformation is predicted to be most stable. MINDO/3-FORCES calculations of the conformations and rotation barriers of similarly methylsubstituted vinyl-cyclopropanes, phenylcyclopropane and 2-cyclopropyl-pyridine are reported. It is found that introducing a methyl group to the a-position of the three membered ring or to the C4 atom f the vinylgroup causes the deviation of the olefine plane from the bisected conformation by 30°. Similar deviations are expected for the a-and o-methyl-phenyl-cyclopropanes. 
  Reference    Z. Naturforsch. 35a, 129—136 (1980); eingegangen am 1. September 1979 
  Published    1980 
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 Identifier    ZNA-1980-35a-0129 
 Volume    35 
22Author    NuhudhD. Bhaya, Muthana ShanshalRequires cookie*
 Title    UV-Absorptionsspektren methylsubstituierter Phenylcyclopropane  
 Abstract    UV absorption Spectra of Me thy I substituted Phenylcyclopropanes The UV absorption spectra of phenyl-cyclopropane(l), 267 nm, 1-methyl-1-phenyl-cyclopro-pane(2), 259 nm, o-tolyl-cyclopropane(3), 264 nm, m-tolyl-cyclopropane (4), 270 nm, and p-tolyl-cyclopropane(5), 280 nm are recorded in the gas phase, in methanol and in n-hexane. The hypso-chromic shifts in the spectra of both 2 and 3 are explained in terms of a twisting of the phenylring out of the bisected conformation which causes an increase in the excitation energy. The spectra of 4 and 5, in which no steric factors are expected to twist the phenylring, show typical inductively caused bathochromic shifts. The vibronic structuring of all the absorption spectra are analyzed and found to include the frequencies 984, 964 and 1100 cm -1 that are attributed to the and the vs vibrations of the cyclopropyl ring in the excited state. The results of the analysis confirm a recent assumption of a strong participation of the zlas Walsh MO of these Molecules in their electronic excitation processes. 
  Reference    Z. Naturforsch. 35a, 137 (1980); eingegangen am 1. September 1979 
  Published    1980 
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 Identifier    ZNA-1980-35a-0137 
 Volume    35 
23Author    J. Jordan, T. Kirsten, H. RichterRequires cookie*
 Title    i29j/i27j. a Puzzling Early Solar System Chronometer  
 Abstract    We report I-Xe ages and other relevant xenon data for seven ordinary chondrites from H and L-groups of petrologic types 4—6, which were selected on the basis of minimum weathering and shock effects. Nevertheless, no chronological order with respect to the I-Xe ages exists among the different petrologic types. We demonstrate, however, that the degree to which the 1-Xe record is preserved in these chondrites, but not necessarily the age, is dependent on the thermal metamorphic history. In order to explain the lack of chronological order among the chondrites, spatiotemporal variations in the condensation-accretion process or inhomogeneities in the isotopic composition of iodine in the solar nebula is required. 
  Reference    Z. Naturforsch. 35a, 145—170 (1980); received November 12 1979 
  Published    1980 
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 TEI-XML for    default:Reihe_A/35/ZNA-1980-35a-0145.pdf 
 Identifier    ZNA-1980-35a-0145 
 Volume    35 
24Author    J. C. Ruffenach, R. Hagemann, E. RothRequires cookie*
 Title    Isotopic Abundances Measurements a Key to Understanding the Oklo Phenomenon  
 Abstract    The Oklo natural nuclear reactors have been studied mainly by isotopic and chemical analyses of uranium and fission products. Interpretation of these analyses allows parameters which char-acterize these reactions (flux, fluence,...), and also the age and duration of the nuclear reactions to be evaluated. The mechanisms and extent of fission-product migration can also be discussed. The behaviour of various elements formed in the Oklo uraninite and in oxyde fuels of pressurized water reactors is compared and found to be similar. Therefore, experience gained from the study of the Oklo phenomenon can provide valuable information on the long-term storage of radioactive wastes in geological media. 
  Reference    Z. Naturforsch. 35a, 171 (1980); received November 26 1979 
  Published    1980 
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 TEI-XML for    default:Reihe_A/35/ZNA-1980-35a-0171.pdf 
 Identifier    ZNA-1980-35a-0171 
 Volume    35 
25Author    Gero Kurat, Alfred KracherRequires cookie*
 Title    Basalts in the Lance Carbonaceous Chondrite  
 Abstract    We describe three lithic fragments from the Lance carbonaceous chondrite which apparently are of igneous origin and of basaltic parentage. They consist of large enstatite grains (pheno-crysts ?) which poikilitically include some olivine and abundant Fe-Ni metal and Fe sulfide blebs. These enstatites are set into a matrix of partly ophitic and partly porphyritic plagioclase (~ an71) and interstitial clinopyroxene and clinopyroxene plus plagioclase intergrowths. Mineral com-positions are highly variable and reflect a complex genesis. Olivine compositions range from fo5 to fo60 and sometimes exhibit compositional zoning. Enstatites are mostly of en 98 com-position with some Fe-enrichment towards grain surfaces and cracks. Plagioclases have about an71 but mostly are altered to nonstoichiometric high-alkali compositions (with original Al/Si ratios corresponding to ~ an 70) or are partly replaced by K-free nepheline. Generally two clinopyroxenes are present within the plagiophyric portions of the fragments: One low Fe/Mg augite (~ en53 wo44) rich in Ti, AI, Cr, and Mn (Fe/Mn ^ 2) and a ferrosalite (~ enl5 wo47) poor in Ti, Cr, and Mn (Fe/Mn ~ 100). One fragment also contains spinel (hercynite) which apparently is xenocrystic in nature. Our investigation indicates: (1) The fragments are of igneous origin. (2) The original melt was of basaltic composition, crystallizing the primary mineral association ol + en + plag + low-Fe augite. (3) During crystallization the melt suffered strong reduction which led to segregation of Fe-Ni droplets from the melt and which continuously lowered the Fe/Mn ratio of successively crystallizing silicates from nearly chondritic (~ 100) to 0.6. (4) Probably after incorporation into the Lance breccia the fragments suffered to different degrees metasomatic alterations which were caused by the addition of Na, K, and Fe to the system. The origin of the pre-Lance basaltic melt cannot yet be established. 
  Reference    Z. Naturforsch. 35a, 180—190 (1980); received November 14 1979 
  Published    1980 
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 Identifier    ZNA-1980-35a-0180 
 Volume    35 
26Author    Swarajranjan Biswas, HungT. Ngo, MichaelE. LipschutzRequires cookie*
 Title    Trace Element Contents of Selected Antarctic Meteorites. I. Weathering Effects and ALH A77005, A77257, A77278 andA77299  
 Abstract    We report data for volatile/mobile Ag, As. Au, Bi, Cd, Co, Cs, Cu, Ga, In, Rb, Sb, Se, Te, TI and Zn in exterior and/or interior samples of four Antarctic meteorites from the Allan Hills (ALH) : A77005 (unique achondrite) ; A77257 (ureilite) ; A77278 (L3) ; A77299 (113). Exterior samples reflect contamination and/or leaching by weathering but trace element (ppm-ppt) contents in in-terior samples seem reasonable for representatives of these rare meteoritic types. The A77005 achondrite seems related to shergottites; other samples extend compositional ranges previously known for their groups or types. With suitable precautions, Antarctic meteorite finds yield trace element data as reliable as those obtained from previously — known falls. 
  Reference    Z. Naturforsch. 35a, 191—196 (1980); received June 1 1979 
  Published    1980 
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 TEI-XML for    default:Reihe_A/35/ZNA-1980-35a-0191.pdf 
 Identifier    ZNA-1980-35a-0191 
 Volume    35 
27Author    Elke Göbel, Uwe Reimold, Hildegard Baddenhausen, Herbert PalmeRequires cookie*
 Title    The Projectile of the Lappajärvi Impact Crater  
 Abstract    Two impact melt samples from the Lappajärvi crater (Scandinavia) are highly enriched in siderophile elements, such as lr, Re, and Os. This indicates the presence of a meteoritic com-ponent. The simultaneous enrichments of Ni, Co, Cr, and Se suggest a chondritic projectile. Because of the relatively large indigenous contributions to Ni, Co, and Cr, it is not possible to distinguish between a normal and a carbonaceous chondrite. The high concentrations of relatively volatile elements could point towards a volatile-rich projectile. The two melt samples have high Re/Ir ratios compared to chondritic ratios. Enrichment of Re relative to Ir is very unusual in terrestrial impact melts. Loss of Re, because of volatilisation under oxidizing conditions or by weathering is frequently observed. The high Re/Ir ratios and the high abundances of relatively volatile elements either indicate the presence of a volatile rich phase or they characterize a type of meteorite, which has not been sampled. Some lunar highland rocks have a pattern of meteoritic elements rather similar to that observed for the Lappajärvi meteorite. The Lappajärvi crater is, after Rocheehouart, the second European crater where a significant amount of meteoritic component has been found. A melt sample from the Lake St. Martin crater (Manitoba), did not show any enrichment in meteoritic elements. 
  Reference    Z. Naturforsch. 35a, 197—203 (1980); received January 9 1980 
  Published    1980 
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 Identifier    ZNA-1980-35a-0197 
 Volume    35 
28Author    Gerlind Dreibus, Heinrich WänkeRequires cookie*
 Title    The Bulk Composition of the Eucrite Parent Asteroid and its Bearing on Planetary Evolution  
 Abstract    It is shown that howardites fit extraordinary well into a binary mixing diagram for both their major and trace element compositions. Eucrites and diogenites would be suitable endmembers. In the mixing diagram computed from the elemental compositions of howardites, we find at a certain position a composition with very special features. This composition designated PR* contains all refractory incompatible elements in almost C 1, i.e. primitive, abundances. If 43% olivine is added to PR* in order to match the C 1 value for the Mg/Si ratio, a composition is obtained which has almost exact C 1 abundance values for all lithophile elements of non-volatile character. Because of its probable genetic relation we have used an olivine composition equal to that of pallasites. An eucrite parent body (EPB) with eucrites, diogenites and pallasites as the major building blocks has been previously suggested by various authors. The bulk composition of the EPB, resulting from our computations is found to be almost chondritic, but with a considerable depletion of volatile and moderately volatile elements. A comparison of the bulk composition of the EPB with that of Earth and Moon reveals a number of remarkable differences. Thus, the similarity of the composition of the silicate phases of Earth and Moon becomes even more remarkable and must be taken as strong indication for the genetic relationship of Earth and Moon. 
  Reference    Z. Naturforsch. 35a, 204—216 (1980); received January 10 1980 
  Published    1980 
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 Identifier    ZNA-1980-35a-0204 
 Volume    35 
29Author    H. Kihara, W. SchnabelRequires cookie*
 Title    High Energy Radiation-Induced Aggregation of Plasma Proteins. Time Resolved Light Scattering Measurements  
 Abstract    Human immunoglobulin (IgG), bovine fibrinogen and bovine serum albumin were irradiated at room temperature with short pulses (50 ns to 2 ;is) of 16 MeV electrons in 0.2 M NaC104 solution containing phosphate buffer (pH 7.5). In the presence of NaO the intensity of light (LSI) scattered by the protein solutions increased after the pulse indicating aggregation. The latter process originates from the attack of protein molecules by OH radicals (aggregation is impeded by t-butanol and augmented by NoO). Upon plotting the relative increase of LSI vs. log time (after the pulse) sigmoidally shaped curves were obtained. From these findings and results of optical absorption measurements the following is inferred: Aggregation occurs as a consequence of chemical alterations of the protein molecules induced by the attack by OH radicals. The transient species formed during and a few pis after the pulse are reacting within a period of several ms. At the end of this period the formation of aggregates starts. It is concluded that the primary radiation chemical process consists (among others) in the generation of nuclcation sites. The latter subsequently initiate aggregation processes. 
  Reference    Z. Naturforsch. 35a, 217—220 (1980); received December 27 1979 
  Published    1980 
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 Identifier    ZNA-1980-35a-0217 
 Volume    35 
30Author    Peter Kroneck, Otto Lutz, Alfons Nolle, Horst OehlerRequires cookie*
 Title      
 Abstract    Tetrahedrally coordinated copper(I) complexes C11L4X have been synthesized, L being P(OR)3, PR3 or P(R)n(OR)3-n, and X being a non-coordinating anion such as Perchlorate or tetra-fluoroborate. Depending on the nature of the bound phosphorus ligand the Cu(I) complexes give well resolved 63 Cu NMR spectra including a quintet signal due to spin-spin coupling between 63 Cu and 31 P. The 63 Cu NMR spectra have been analyzed with reference to the chemical shift (), the shielding constant a* (given on an absolute atomic scale), the linewidth Av, and the coupling constant J(63 Cu-31 P). Generally, the relative magnitude of these NMR parameters are in satis-factory agreement with results reported for isoelectronic Ni(O) complexes with the phosphorus ligands mentioned above. Furthermore, the NMR properties of the Cu(I) compounds are discussed in terms of cr-donor or 7r-acceptor capacities of the ligands coordinated, and stereochemical properties of the complexes. 
  Reference    Z. Naturforsch. 35a, 221—225 (1980); received December 24 1979 
  Published    1980 
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 Identifier    ZNA-1980-35a-0221 
 Volume    35 
31Author    P. Kroneek, 0. Lutz, A. NolleRequires cookie*
 Title    NMR Investigations of 17 0, 33 S, 95 Mo, and 97 Mo in Thiomolybdates  
 Abstract    NMR investigations of 1T 0, 33 S, 95 Mo, and 97 Mo have been used to elucidate the existence and the behaviour of the oxothiomolybdate species, Mo04-nSn 2-(n — 0, 1, 2, 3, 4) in aqueous solution. Very large chemical shifts and surprisingly narrow lines have been found for these nuclei in the different species. 
  Reference    Z. Naturforsch. 35a, 226—229 (1980); received December 24 1979 
  Published    1980 
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 Identifier    ZNA-1980-35a-0226 
 Volume    35 
32Author    B. P. Singh, L. P. Pathak, M. P. HemkarRequires cookie*
 Title    Lattice Dynamics of Molybdenum and Chromium  
 Abstract    The frequency-wave vector dispersion relations, the frequency spectrum, the Debye tempera-ture, the temperature dependence of the Debye-Waller factor and the mean square displacements of the atoms molybdenum and chromium, the metals for which long range forces are also impor-tant, have been computed on the basis of the extended improved Fielek model for BCC transition metals. The model considers, for the first time the d shell-d shell central interactions upto next-nearest-neighbours. The calculated results show a satisfactory agreement with the available ex-perimental data. 
  Reference    Z. Naturforsch. 35a, 230—235 (1980); received November 9. 1979 
  Published    1980 
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 Identifier    ZNA-1980-35a-0230 
 Volume    35 
33Author    E. Erdle, H. MöhwaldRequires cookie*
 Title    Mini-Excitons and Lattice Dynamics in Mixed CT-Crystals: An ESR, Optical and Raman Spectroscopical Study  
 Abstract    Mixed CT-crystals of composition anthracenecphenanthrenei.c-tetracyanobenzene (AnthfPheni.c-TCNB, 0 < c 5S 1) have been investigated using ESR, optical and Raman spectroscopy. The data yield information on structural features and exciton transport as well as on the interrelation be-tween these properties. With respect to their structural properties the mixed crystals can be separated into two classes: a) Crystals with excess phenanthrene (c ^ 0.5) behave like Phen-TCNB exhibiting two donor orientations and lacking molecular motion as well as a phase transition, b) Crystals with excess anthracene (c > 0.5) are comparable to Anth-TCNB: they also undergo a first order phase transi-tion, though at a lower transition temperature ft (ITt = 155K for c = 0.75, whereas 7\ = 206 K for c = l). Mini-triplet-excitons confined to the anthracene moiety were found. Their diffusion takes place quasi-onedimensionally and independently of temperature, i. e. especially without being affected by the phase transition. This result holds for the fast component of the diffusion tensor as well as for the slow one. 
  Reference    Z. Naturforsch. 35a, 236—243 (1980); received December 18 1979 
  Published    1980 
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 Identifier    ZNA-1980-35a-0236 
 Volume    35 
34Author    J.A M S Duarte, H. J. RuskinRequires cookie*
 Title    The Change in the Prefactor Exponent with Valence for Percolation in 3 and 4 Dimensions  
 Abstract    The change of the prefactor exponent for restricted valence percolation in 3 and 4 dimensions is shown to occur between valences 2 and 3 as in 2 dimensions. For valence 2 the exponent is SAW-like and after the change it assumes the normal percolative value for each dimension. 
  Reference    Z. Naturforsch. 35a, 244—246 (1980); received November 18 1979 
  Published    1980 
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 Identifier    ZNA-1980-35a-0244 
 Volume    35 
35Author    Werner UrlandRequires cookie*
 Title    Magnetische Eigenschaften der Normaltemperaturform von CsYbO  
 Abstract    The magnetic behaviour of the normal-temperature form of CsYb02 has been studied in the temperature range between 2.8 and 251.3 K. Besides at temperatures below about 12 K the magnetic data are well interpreted by means of a model in which the influence of the crystal field is theoretically described by the angular overlap model and the influence of magnetic interaction by the molecular field model. By this the transferability of the angular overlap parameters from one compound to another is tested. The energy values of the crystal-field levels of the 2 Fy/2 ground state are calculated. 
  Reference    Z. Naturforsch. 35a, 247—251 (1980); eingegangen am 4. Januar 1980 
  Published    1980 
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 TEI-XML for    default:Reihe_A/35/ZNA-1980-35a-0247.pdf 
 Identifier    ZNA-1980-35a-0247 
 Volume    35 
36Author    Fritz BoppRequires cookie*
 Title    Quarks im Lichte einer Idee von Pais Quarlcs According to an Idea of Pais  
 Abstract    A wave equation of a kind proposed by Pais in 1953 describes a particle with an infinite sequence of quantum states, which belong to the symmetrical representations (A, 0) of the group SU 3. Particles composed of such single ones are connected with the whole set of representations (A, /li) of SU 3. The wave equation is compatible with an exclusion principle. Assuming that only particles with zero triality occur, all quarks and quarklike particles are excluded. Neither coulours, nor bags are needed, as we do not need repulsive forces to exclude Li-atoms with symmetrical wave functions. 
  Reference    Z. Naturforsch. 35a, 252—253 (1980); eingegangen am 26. November 1979 
  Published    1980 
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 Identifier    ZNA-1980-35a-0252_n 
 Volume    35 
37Author    T. S. Rao, R. N. JukarRequires cookie*
 Title      
 Abstract    Electrophilic substitution in aromatic substrates by iodine monochloride is about 10 5 times faster than by iodine in potassium iodide. This is due to the permanent dipole in the iodine monochloride, with iodine as the positive end, which greatly facilitates electrophilic attack. 
  Reference    Z. Naturforsch. 35a, 254—255 (1980); received December 18 1979 
  Published    1980 
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 Identifier    ZNA-1980-35a-0254_n 
 Volume    35 
38Author    J. H. Reynolds, G. R. Lumpkin, P. M. JefferyRequires cookie*
 Title    Search for 129 Xe in Mineral Grains from Allende Inclusions: An Exercise in Miniaturized Rare Gas Analysis  
 Abstract    A static mass spectrometer, modified by installation of a Baur-Signer (Zürich) ion source and an ion-counting system, was used to detect xenon from single mineral grains from inclusions in the C3 meteorite Allende. The grains were melted in small conical heaters wound from tungsten wire. In almost all cases excess 129 Xe from 129 I decay was detected, in concentrations varying from < 1000 to 600,000 atoms per microgram. Inferred iodine concentrations increased on the average from pentlandite (0.6 ppb), to hedenbergite (21 ppb), to olivine (92 ppb), to enstatite (203 ppb) to melilite (422 ppb), but vary widely from one grain to another of the same mineral, indicating that the iodine resides in some minor phase which is included "spottily" in the bulk phases over which we had good mineralogical control. About 23,000 atoms of fissiogenic 132 Xe, presumably from 244 Pu decay, was detected in the largest melilite sample analyzed, but we cannot determine from this study whether the 244 Pu is "spotty" like 129 I or is uniformly distributed in the melilite. One can foresee that if the samples could be loaded into previously outgassed heater cones, a system such as the one described in this paper would have 132 Xe blanks of ~ 50,000 atoms. It is likely that in such a system the detectability for excess Xe achieved in this paper (~ 20,000 atoms) could be substantially improved. We also ran St. Severin troilite, which contains less than ~ 33 atoms of excess 129 Xe per microgram, and a single chondrule from Allegan, which contains higher concentrations of radiogenic xenon than were previously reported by Podosek from runs on a pile-irradiated sample. Introduction The iodine-xenon method of dating meteorites, which has been practiced since 1960 [1] and has recently showed signs of furnishing useful chrono-logical information [2 — 4], has always suffered from our ignorance about the iodine sites in the rocks being studied. Since it has been clear that the ultimate sensitivity of the method has never been closely approached in practice, we undertook [as a sabbatical leave project for one of us (JHR) ] a search for excess 129 Xe in hand-picked mineral grains from inclusions in the Allende C 3 car-bonaceous chondrite. Essential to the project was miniaturization of the techniques for analysis of 
  Reference    Z. Naturforsch. 35a, 257—266 (1980); received January 7 1980 
  Published    1980 
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 Identifier    ZNA-1980-35a-0257 
 Volume    35 
39Author    Mineo Imamura, Masako Shima, Masatake HondaRequires cookie*
 Title    Radial Distribution of Spallogenic K, Ca, Ti, V and Mn Isotopes in Iron Meteorites  
 Abstract    Cosmic-ray-produced stable nuclides of Ca (mass number: 42, 43, 44 and 46), Ti (46, 47, 49 and 50), V (50), Cr (50, 53 and 54) and the long-lived nuclides, 40 K and 53 Mn were determined along the radial axes of the iron meteorites Grant and Treysa. Grant was extensively examined and the results compared with rare gas data. Although Treysa does not include enough samples to allow detailed analysis, the depth profile shows typical features for a small meteorite. The results were compared with calculated profiles of 40 K, 49 Ti and 53 Mn using thick bombard-ment data. The approximate pre-atmospheric radii of Grant and Treysa were determined to be 30 cm and 14 cm, respectively. The effect of space erosion was also estimated by comparing the data of 49 Ti and radioactive 53 Mn in Grant and Treysa with the calculated patterns. It is suggested that space erosion of both meteorites is small (<0.8Ä/y) during the cosmic-ray exposure of several hundred million years. 
  Reference    Z. Naturforsch. 35a, 267—279 (1980); received January 7 1980 
  Published    1980 
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 Identifier    ZNA-1980-35a-0267 
 Volume    35 
40Author    Helmut HebenstreitRequires cookie*
 Title    Wave Propagation in a Moving Cold Magnetized Plasma  
 Abstract    Polarization relations and dispersion equations are derived for media electrically anisotropic in the comoving frame. The obtained results are discussed mainly for cold magnetized plasmas, briefly for uniaxial dielectric crystals. Special directions of wave propagation are considered. 
  Reference    Z. Naturforsch. 35a, 280—292 (1980); received November 23 1979 
  Published    1980 
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 TEI-XML for    default:Reihe_A/35/ZNA-1980-35a-0280.pdf 
 Identifier    ZNA-1980-35a-0280 
 Volume    35 
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