Studien zum Vorgang der Wasserstoffübertragung, 57 Einige Beispiele zur diastereoselektiven Hydrierung von Verbindungen mit prochiralen CC-Bindungen

1979

(1R,2S)-N,N-Dimethylephedriniumchlorid, (1S,2S)-N,N-Dimethylpseudoephedriniumchlorid, (1R,2S)-N-Methylephedrin, (1S,2S)-N-Methylpseudoephedrin und [(2S)-2-Hydroxy-2-phenyl-ethyl]trimethylammoniumchlorid werden mit α- und β-Methylzimtsaure zu 1–4 und 7 verestert und an Raney-Nickel, Palladium, Platin und einer Reihe von Edelmetalltragerkatalysatoren hydriert. Die hydrierten Ester werden verseift und die optische Ausbeute der α- bzw. β-Methyldihydrozimtsaure bestimmt. Die optischen Ausbeuten bewegen sich in Abhangigkeit von der optisch aktiven Hilfskomponente zwischen 68 und 4%. Bei optischen Ausbeuten uber 10% wird die absolute Konfiguration der α- oder β-Methyldihydrozimtsaure von der Konfi…

The intensification of absorbance changes in leaves by light-dispersion

1979

In dispersive samples, like leaves, the absorbance of pigments is intensified. The intensification is due to a longer optical path through the dispersive sample. However, in chloroplast suspensions the optical path is not much longer than in clear solutions. The factor of intensification β (=the lengthening of the optical path) is calculated by comparing the absorbance of leaves and the absorbance of chloroplast suspensions with equal pigment-content. This method also includes the influence of possible sieve effects which could decrease absorbance. The measurements are carried out with high- and low-light leaves of different thickness and pigment content. The intensification of absorbance w…

Regularity of the solution to a class of weakly singular fredholm integral equations of the second kind

1979

Continuity and differentiability properties of the solution to a class of Fredholm integral equations of the second kind with weakly singular kernel are derived. The equations studied in this paper arise from e.g. potential problems or problems of radiative equilibrium. Under reasonable assumptions it is proved that the solution possesses continuous derivatives in the interior of the interval of integration but may have mild singularities at the end-points.

Ground state correlations and the nuclear charge distribution

1979

Combining a sum rule approach and the generator coordinate model we evaluate the influence of ground state correlations on the moments of the radial charge distribution. The isotopic and isotonic differences of the moments come out to be particularly sensitive to fluctuations of the ground state correlations due to changes in the low energy spectrum. A comparison with the experimental results for the isotopes of Ca, Fe, Ni and Zn shows a fair agreement and confirms the importance of the ground state correlations for isotopic and isotonic differences of radial moments.

STUDIEN ZUM VORGANG DER WASSERSTOFF- ÜBERTRAGUNG 561 Elektroreduktive Spaltung der N–S Bindung in Sulfenamiden und Sulfenimiden

1979

Von funf Benzo-1,3-thiazol-2-sulfenamiden (1–5) und drei N-Thiolkyl-bzw. N-thioarylsubstituierten Succinimiden (6–8) werden polarographisch die Halbstufenpotentiale bestimmt (Tabelle I) und der Ver...

One- and multi-locus multi-allele selection models in a random environment

1979

We deduce conditions for stochastic local stability of general perturbed linear stochastic difference equations widely applicable in population genetics. The findings are adapted to evaluate the stability properties of equilibria in classical one- and multi-locus multi-allele selection models influenced by random temporal variation in selection intensities. As an example of some conclusions and biological interpretations we analyse a special one-locus multi-allele model in more detail.

Grapeseed as a possible source of food protein

1979

Book Review: Foundations of Christian Faith

1979

Multiplizit�ten ?unendlich-ferner? Spitzen

1979

LetX be the quotient of a bounded symmetric domainD by an arithmetically defined subgroup Γ of all analytic automorphisms ofD and letX * be theSatake-compactification ofX. In the present note, the multiplicities of the local rings of the zero-dimensional boundary components ofX * will be computed in a completely elementary manner using reduction-theory in selfadjoint homogeneous cones.

Analyse économique et technologies éducatives non conventionnelles dans l'enseignement supérieur

1979

International audience

Heat transport of helium II in restricted geometries

1979

The linear heat transport of helium II contained in porous powder samples with mean pore diameters of 1.25µm, 0.17µm and 0.02µm was systematically studied in the temperature range between 0.8 K and 2 K. The effective thermal conductivity was determined by steady-state heat flow measurements and the effective thermal diffusivity by transitory temperature measurements. The experimental results are interpreted by a simple theoretical model. In the framework of this model the linear heat transport consists of two contributions: the laminar flow of the normal fluid (T≳1.4 K) and a diffusion mechanism (T≲1.4 K). At low temperatures (T≲1.2 K) the mean free paths of the elementary excitations of he…

Numerische Behandlung von Verzweigungsproblemen bei gew�hnlichen Differentialgleichungen

1979

We present a new method for the numerical solution of bifurcation problems for ordinary differential equations. It is based on a modification of the classical Ljapunov-Schmidt-theory. We transform the problem of determining the nontrivial branch bifurcating from the trivial solution into the problem of solving regular nonlinear boundary value problems, which can be treated numerically by standard methods (multiple shooting, difference methods).

Decay of24Al and24Almto γ-Ray and α-Particle Emitting States in24Mg

1979

The level structure of 24Mg and decay properties of 129 ms 24Alm and 2.07 s 24Al have been investigated by means of γ-ray and particle spectroscopy. The energy and intensity of the isomeric transition were measured to be 425.8 ± 0.1 keV and (82.5 ± 3.0)%, respectively. The isomer was observed to decay via a super-allowed transition with a log ft value of 3.51 ± 0.04 to its 1+, 9965.2 ± 1.5 keV analog state in 24Mg. In addition, decay to seven particle-emitting levels and four levels depopulated by γ-ray emission were observed. In the decay of 2.07 s 24Al a new delayed α-particle group with an energy 3.04 MeV and three new γ-transitions were observed. More accurate values than those reported…

Mercury and chlorinated hydrocarbons in zoobenthos of Lake Päijänne, Finland

1979

The average amounts of mercury, PCBs, and sigma DDT (primarily DDE), found in macrozoobenthos, on the wet basis, in Lake Päijänne, Finland, for the time period 1972-1974, were 79 ng/g, 29 ng/g, and 8 ng/g, respectively. Lindane was found in negligible amounts in only 2% of the samples examined; aldrin was present in 10% of the samples; no dieldrin was detected. Mercury and PCB concentrations varied regionally in the lake. PCB and sigma DDT concentrations were greater in the predatory bottom animals than in the herbivores or detritus feeders, and the amounts of chlorinated hydrocarbons were greater in profundal animals than in littoral animals. No significant correlation was apparent between…

MÖSSBAUER SPECTROSCOPIC STUDIES OF SPIN CROSSOVER COMPOUNDS

1979

Oxide growth and tunneling characteristics of Sn-SnO x -Sn junctions

1979

Sn—SnOx—Sn tunneling junctions were prepared by thermal oxidation of vacuum deposited Sn-films. The thickness growth of the oxide was followed by ellipsometric measurements. From logarithmic conductivity measurements the barrier heights were determined. The tunneling characteristic could be well described by the two-band-tunneling model using a value of 0.14 for the ratio of the effective masses in the oxide and the metal.

On t-covers in finite projective spaces

1979

A t-cover of the finite projective space PG(d,q) is a setS of t-dimensional subspaces such that any point of PG(d,q) is contained in at least one element ofS. In Theorem 1 a lower bound for the cardinality of a t-coverS in PG(d,q) is obtained and in Theorem 2 it is shown that this bound is best possible for all positive integers t,d and for any prime-power q.

Polymerization of styrene

1979

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1979

The autosomal recessive (Becker) form of myotonia congenita

1979

In the last two decades, two genetically distinct forms of myotonia congenita have been identified--an autosomal dominant and an autosomal recessive form. The purpose of this review is to describe the features that enable us to distinguish between these two forms in the absence of sufficient genetic data. Thus far, it can be concluded that the only probable difference between the two forms is in the fatty-acid pattern of muscle phospholipids. Clinical, histologic, ultrastructural, and electromyographic investigation may prove helpful, but they alone cannot provide a reliable means of identifying the genotype in an individual patient.

Die Anwendung der Dynamischen Optimierung bei der Sozial-Sanitären Bezirkseinteilung

1979

Nach einer kurzen Analyse des Problems der optimalen Aufteilung eines geographischen Gebietes in sozial-sanitare Bezirke wird in der vorliegenden Arbeit fur die Losung eines solchen Problems ein Modell dynamischer Programmierung verwendet. Es werden dann zwei Algorithmen vorgeschlagen: der erste, der von der territorialen Einheit ausgeht, soll die zulassigen sozial-sanitaren Bezirke unter Berucksichtigung der Faktoren Nahe, Dichte und begrenzter Bevolke-rungsunterschied ermitteln; der zweite errechnet jene Gesamtheit der zulassigen Bezirke, die, jede territoriale Einheit nur einmal „deckend“, eine Zielfunktion auf ein Minimum reduziert, die das Gleichgewicht zwischen Angebot und Nachfrage d…

Measurements on the temperature dependence of the cationic polymerization of styrene in CH2Cl2 with CF3SO3H as catalyst

1979

The cationic polymerization of styrene in CH2Cl2 with CF3SO3H as catalyst and at low monomer concentrations shows, at −15°C, −45°C and −60°C, the same formal dependence on monomer concentration. The dependence on the catalyst concentration is approximately but not exactly of a third order.

Reconciling high-transverse-momentum dimuon production with quantum chromodynamics

1979

It is shown that by taking into account nuclear effects in a phenomenological model-independent way, the recent Fermilab data for of muon pairs may be reduced to values compatible with quantum-chromodynamics predictions. The sensitivity of this reduction to uncertainties in the assumed nuclear dependence are discussed.

Pharmakologisch-aktive polymere, 19. Polymere mit kovalent gebundenem streptomycinsulfat

1979

Mononuclear heterocyclic rearrangements. Part III. Rearrangement of theP-methoxyphenylhydrazone and them-nitrophenylhydrazone of 3-benzoyl-5-phenyl-1…

1979

The rates of the mononuclear heterocyclic rearrangement of the p-methoxyphenylhydrazone (Ib) and the m-nitrophenylhydrazone (1c) of 3-benzoyl-5-phenyl-1,2,4-oxadiazole have been measured in the range of pS+ 3.8–11.5 (solvent: dioxane/water 1:1, v:v) and compared with those of the unsubstituted phenylhydrazone (Ia). The obtained results show that in the base-catalyzed range, electron-repelling as well as electron-withdrawing substituents accelerate the rearrangement rates.

Analyse des coûts du projet "manuels scolaires aux Philippines"

1979

Référence interne : 79004

Pharmakologisch-aktive polymere, 18. Körperverteilung und ausscheidungsverhalten von monomerem und polymerem sulfadiazinacrylamid

1979

Sulfadiazinacrylamid was absorbed after oral and intraperitoneal application in rats to a high extent; the absorption from the intraperitoneum was retarded. Glucose treatment delayed the absorption after both application forms. At comparatively high renal and enteral excretion rates the biological half life time of the monomer was estimated to 8 h. A tumouraffinity was not found but there were indications for a preferred storage in the RES. Poly[sulfadiazinacrylamide] was absorbed after intraperitoneal injection to a clear extent, where at the beginning of the treatment under simultaneous glucose load the absorption was delayed. 24 h after injection higher concentrations in metabolic organs…

Toxicity of 4-chloro-O-cresol to rat: I. Light microscopy and chemical observations.

1979

TEXTURE PROBLEMS AND THE GOLDANSKII-KARAGIN EFFECT TREATED BY THE INTENSITY MATRIX METHOD

1979

The texture problem and the Goldanskii-Karyagin effect are easy to survey if the intensities of the transitions are written in terms of the intensity matrix. For pure magnetic and quadrupole interaction the equations are explicitly given.

Closure operations for Schunck classes and formations of finite solvable groups

1979

The purpose of the present note is to investigate the closure operations common to both the operations of forming classes and formations. Furthermore, new descriptions of formations and saturated formations in terms of closure operations are given.

Polymerization of styrene

1979

Electroproduction of low energy charged pions on9Be,12C and16O

1979

Measurements of electroproduced pions with an energy of 10MeV are presented. The results of a calculation based on the PWIA are compared with the presented data as well as with data at higher pion energies.

Eine Beziehung zwischen Regularitätsbedingungen für Faserungen

1979

This is the proof of a theorem which states a relation between some regularity conditions for spreads.

Short- and long-term effects of vinblastine on the rat adrenal medulla

1979

The effects of a single high dose (10mg/kg) of vinblastine (vb) sulfate (“Velbe”, Lilly) on the ultrastructure, catecholamine (CA) content and activity of CA-synthesizing enzymes of the rat adrenal medulla were studied for up to 120h after intravenous injection of the drug.

Comment déterminer l'azote "minéralisable" dans des boues résiduaires ?

1979

Zur Histopathologie der Niere beim Pseudo-Bartter-Syndrom durch chronischen Diuretikaabusus

1979

Bei einer 38jahrigen Patientin entwickelte sich ein Pseudo-Bartter-Syndrom mit hypokaliamischer Alkalose, Hyponatriamie und Hyperreninamie infolge eines mehr als 10jahrigen Abusus von Diuretika (Furosemid, Spironolacton, Thiabutazid). Als nierenbioptische Befunde werden eine Hyperplasie des iuxtaglomerularen Apparates und der Mesangiumzellen als morphologisches Substrat des Hyperreninismus sowie eine herdformige Vakuolisierung von proximalen Tubuluszellen und eine herdformige Atrophie der distalen Tubuli beschrieben. Die Genese der tubularen Veranderungen und ihre mogliche Beziehung zu kaliopenischen, hypoxischen oder medikamententoxischen Einflussen wird diskutiert, kann jedoch nicht befri…