Untersuchungen zur Reaktion von konzentrierter Phosphors�ure mit reinen und korrodierten Stahloberfl�chen

1984

Mittels Mosbauerspektroskopie wurde gefunden, das sich aus Rostkomponenten neben den normalen Eisen (III)- und Eisen (II)-phosphaten auch ein saures Eisen (III)-phosphat bilden kann, wenn sie mit konzentrierter Phosphorsaure behandelt werden. Voraussetzung hierfur ist, das die Ausgangsphase eine reine Fe3+-Verbindung ist. Das saure Eisen(III)-phosphat, wahrscheinlich FeH3(PO4)2 · 2,5 H2O, enthalt Fe3+ in nahezu kubischer Umgebung, die Kristallstruktur hat jedoch niedrigere Symmetrie. Unterhalb von 28 K setzt eine magnetische Ordnung ein. Es sind zwei Falle mit verschiedener Spinstruktur und Verkantungen zu unterscheiden.

Half-life and configuration of the 1/2+ intruder state in203Bi

1984

The decay properties of theJπ=1/2+,Eexc=1,098 keV state in203Bi were studied. The state was populated via the204Pb(p, 2n) reaction and the activity was studied with the ion guide isotope separator on-line system IGISOL. The half-life of the 1/2+ state was measured to beT1/2=303 ±5 ms. From this value the partial half-lives of the three depopulating branches 1/2+ →7/2− (E3), 1/2+→5/2− (E3 +M2) and 1/2+→9/2 g.s. − (M4) were deduced. Since all the transitions are configuration forbidden in first order, a detailed study of second-order shell-model configuration mixing could be performed.

Mass and low-lying levels ofIn106,108from theCd106,108(p,nγ)reactions

1984

106In has been studied via the reaction 106Cd(p,nγ)106In in the energy range Ep=7-9 MeV. Inbeam γ-ray excitation functions, γ-γ coincidence measurements, and β+-delayed γ-ray excitation functions have been used to identify thirteen levels in 106In. From this new level scheme the energy separation of the high-spin ground state and the low-spin isomer has been determined to be 28.6±0.5 keV. The threshold energy of the strongest low-lying γ-ray transition yields a mass excess for 106In of -80601±15 keV. Spins for some states are suggested by comparing the excitation functions to Hauser-Feshbach calculations. In-beam γ-ray excitation functions for the 108Cd(p,nγ)108In reaction give a mass exces…

WIGNER TRANSFORM METHODS IN INCLUSIVE ELECTRON SCATTERING FROM NUCLEI

1984

A multiple scattering series for deep inelastic leptoninduced reactions is derived by using semiclassical Wigner transform methods. In contrast to the usual Glauber theory there is no limitation for the energy loss since a time-dependent formulation is used throughout. A simple parametrization of the generalized profile function yields a closed analytical expression for the longitudinal and transverse response function of p-shell nuclei. Comparison is made with the Saclay data for -'• C. I Introduction It is common knowledge that geometrical optics is valid if the wavelength of the scattering wave is small compared to the dimensions of the scatterer. Under these conditions the phase-space d…

Observations on the effects of cyclophosphamide, phosphoramide mustard and some activated oxazaphosphorines on murine L1210 leukemia.

1984

The L1210 tumor system was used in vitro and in vivo in comparative studies with activated cyclophosphamide analogs, cyclophosphamide and phosphoramide mustard. All the above compounds gave substantial cell kills (5 logs) of L1210 in vivo at doses that were non-toxic, but slight differences were noted. ASTA Z 7557 had a slight advantage in cure rate over cyclophosphamide when these drugs were given i.v. or i.p. to early tumor (i.p.). However, cyclophosphamide had the advantage in cure rate when drug administration was i.v. to advanced tumor. At equimolar concentrations in vitro ASTA Z 7557 was more cytotoxic than either phosphoramide mustard or acrolein. In vivo, the activated cyclophospham…

Die Tentakuliten aus dem Frasnium (Ober-Devon) von Ghuk (westliches Zentral-Afghanistan)

1984

Es werden Tentakuliten des Frasniums aus dem westlichen Zentral-Afghanistan beschrieben. Von den 11 untersuchten Arten sind 6 neu:Dicricoconus dupliannulatus n. sp.,Dicricoconus ghukensis n. sp.,Dicricoconus gracilis n. sp.,Dicricoconus harundata n. sp.,Volynites kaminjensis n. sp. undAlternatus spatiosus n. sp. Die Fauna tritt in zwei stratigraphischen Niveaus auf. Das mittelbis oberfrasnische bzw. oberfrasnische Alter der beiden Niveaus wird durch das Vorkommen vonTentaculites donensis bzw.Dicricoconus tichomirovi,Dicricoconus tragula undUniconus livnensis bestatigt. Die palaogeographischen Verhaltnisse lassen auf Verbindungen mit dem Epikontinentalmeer der Russischen Plattform wahrend de…

Evidence for rotational bands in103Nb

1984

The nucleus103Nb62 has been studied through the s− decay of the fission product103Zr at LOHENGRIN and JOSEF. The energies of the lowlying levels and the γ transitions indicate rotational bands based on the Nilsson proton configurations [422 5/2+] [303 5/2−] and [301 3/2−] at 0, 164 and 248 keV, respectively. The measured half-lives of (4.7±0.5) ns and (2.0±0.6) ns of the levels at 164 and 248 keV are consistent with the Nilsson-model estimates including pairing.

Effects of β-adrenergic blockade on EMG signal characteristics during progressive exercise

1984

High-spin bands in117,119I and118Xe

1984

Excited states in117I,118Xe and119I were populated in the reactions106Pd+16O and108, 110Cd+12C. The groundstate band in118Xe was observed to its (18+) member and the 11/2− bands in117I and119I to their (35/2−) and (43/2−) members, respectively. The structure of the bands in the I isotopes is interpreted as aπ h11/2 proton coupled to an even-even band structure in Xe, and the band crossings observed in118Xe and119I are interpreted in the Cranked Shell Model framework asABn ofv h11/2.

Inelastic neutron scattering study of the rotational excitations in(KBr)1−x(KCN)xin the paraelastic and structural glass state

1984

The coupled rotational-translational excitations in ${(\mathrm{KBr})}_{1\ensuremath{-}x}{(\mathrm{KCN})}_{x}$ were studied by inelastic neutron scattering for concentrations $0.008\ensuremath{\le}x\ensuremath{\le}0.20$. We followed the ${A}_{1g}\ensuremath{-}{T}_{2g}$ tunneling transition and the ${A}_{1g}\ensuremath{-}{E}_{g}$ librational excitation through the transition from the paraelastic to the structural glass state. We found that these two excitations and their coupling to the lattice strains exhibit a very different temperature dependence in the glass state. While the tunneling transition, which triggers reorientations of the ${\mathrm{CN}}^{\ensuremath{-}}$ ions, shows a drastic r…

Position Analysis of Spatial Mechanisms

1984

In this paper matrix notation is used to develop a computational algorithm for position analysis of spatial mechanisms having revolute (R) and prismatic (P) pairs. Since all lower pairs are equivalent to some combination of R and P pairs, the method works for spatial mechanisms containing any lower pair. By using the method, spatial mechanisms are describable by simple equations which are easily programmable.

Rare decay modes of the neutral pion

1984

3 páginas, 2 figuras, 1 tabla.

The invariant chains of mouse class II antigens: biochemical properties and molecular relationship

1984

The proteins p40 (Mr = 40 000), p32 (Mr = 32 000), p28 (Mr = 28 000), p20 (Mr = 20 000) and p10 (Mr = 10 000) are described which occur in noncovalent association with the polymorphic alpha, beta heterodimer of class II antigens. They were investigated with respect to their molecular characteristics and their mutual structural relationship. p32, the predominant species of this group corresponds to the invariant chain gamma (Ii). In contrast to the polymorphic subunits alpha and beta, proteins p40, p28, p20 and p10 migrated like gamma in electrophoretically constant positions, when class II molecules of different subregions and different alleles were assessed by two-dimensional gel electroph…

Occidentalisation ou modèles nationaux : le cas des services éducatifs

1984

International audience

Theory of hydrogen and helium impurities in metals

1984

A powerful computational scheme is presented for calculating the static properties of light interstitials in metallic hosts. The method entails (i) the construction of the potential-energy field using the quasiatom concept, (ii) the wave-mechanical solution of the impurity distribution ("zero-point motion"), (iii) calculation of the forces exerted on the adjacent host atoms and their displacements, and (iv) iteration to self-consistency. We investigate self-trapping phenomena in bcc and fcc metals in detail, and calculate both the ground and low-lying excited states. Implications of the wave-mechanical or band picture to diffusion mechanisms and inelastic scattering experiments are discusse…

Electron scattering mechanisms inn-type indium selenide

1984

Electron scattering mechanisms in $n$-type indium selenide are investigated by means of the temperature dependence (4-500 K) of Hall mobility and the magnetic field dependence of Hall and magnetoresistance coefficients. The Schmid model for homopolar optical-phonon scattering can explain the temperature dependence of electron mobility above 40 K. The electron-phonon coupling constant is determined, ${g}^{2}=0.054$. The optical phonon involved in the process is identified as the ${A}_{1}^{\ensuremath{'}}$ phonon with energy 14.3 meV. The magnetic field dependence of Hall and magnetoresistance coefficients is discussed in terms of the Jones-Zener expansion.

Synthesis of peptides with α,β‐dehydroamino acids, I. synthesis of N‐benzyloxycarbonyl and N‐trifluoroacetyl dipeptides of dehydroalanine and dehydro…

1984

Condensation of amides of N-(benzyloxycarbonyl)- and N-(trifluoroacetyl)amino acid with pyruvic and phenylpyruvic acid yields, in the presence of p-toluenesulfonic acid as a catalyst, N-(benzyloxycarbonyl)- and N-(trifluoroacetyl)dehydro dipeptides with C-terminal Δ Ala and ΔPhe, respectively (Table 2 and 3). Synthese von Peptiden mit α,β-Dehydroaminosauren, I. - Synthese von N-(Benzyloxycarbonyl)-und N-(Trifluoracetyl) dipeptiden von Dehydroalanin und Dehydrophenylalanin Die Kondensation von Nα-(Benzyloxycarbonyl)- und Nα-(Trifluoracetyl)aminosaureamiden mit Brenztrauben- und Phenylbrenztraubensaure in Gegenwart von p-Toluolsulfonsaure als Katalysator fuhrt zu N-(Benzyloxycarbonyl)- und N-…

The chemical ionisation mass spectra of alcohols

1984

National audience

Spectrophotometric determination of fluoride in fluoride-bearing minerals after decomposition by fusion with sodium hydroxide

1984

The decomposition of highly insoluble minerals (fluorspar and cryolite) by fusion with molten alkali-metal hydroxides is studied. The introduction of additives such as aluminium compounds or sodium peroxide to obtain total liberation of fluoride from calcium fluoride samples, is tested. The fusion is done in a silver crucible with a Bunsen burner. The cooled melt is easily soluble, giving solutions suitable for spectrophotometric fluoride determination by the Zr(IV)-fluoride-Erichrome Cyanine R method.

Real-time ultrasound of normal adrenal glands and small tumors.

1984

The adrenals were studied prospectively with real-time ultrasound in a series of 60 healthy individuals and 13 patients with small adrenal masses sized 8-20 mm in diameter. In only one of the 60 healthy subjects was a normal adrenal gland delineated as a distinct hypoechoic structure. In all other instances only the highly echogenic suprarenal fat could be displayed. Visualization of small tumors was successful in 12 of 13 patients. The suprarenal area and small lesions were best demonstrated by a lateral intercostal approach using longitudinal and transverse scanning planes. The best access was through the 9th/10th intercostal space at the junction with the anterior and middle axillary lin…

Rupture of supra-aortic neck arteries due to lesions caused by tracheal tubes

1984

Haemorrhages from the common carotid or innominate artery caused by tracheal tubes are rare but dramatic complications of head and neck surgery. Patients with metal tracheostomy cannulas or patients in the phase of wound healing after radical tumour resections of the pharynx and larynx run a greater risk. Following extensive tumour resections and radiation of the upper respiratory and digestive tracts in 680 patients, acute bleeding of the larger neck arteries occurred in 18 patients. In four of these cases, fistulae developed in the innominate or common carotid artery. These ruptures were caused by both plastic and metal tracheal tubes.

Mean 14.00-17.00 h plasma cortisol concentration and its relationship to the 1 mg-dexamethasone suppression response in depressives and controls.

1984

Three-hour cortisol-profiles and cortisol responses to a 1 mg dose of dexamethasone were recorded in 31 depressed patients and nine controls. The data indicate that the likelihood of detecting non-suppressible cortisol concentrations after dexamethasone is significantly increased in depressed patients with a hypersecretion of cortisol. However, a considerable subsample of normosecretors shows abnormal DST results. Conversely, hypersecretion is often associated with dexamethasone suppression. In this study a 1 mg-DST did not reflect the adrenocortical activity with ultimate accuracy. Therefore any attempts which correlate psychopathological or biological data with pituitary-adrenal activity …

Order and disorder in mixed metal linear chains: The homo and heterobimetallic EDTA (M(H2O)4OIOII)[M?(EDTA)] � 6H2O complexes (M = Mg, Mn, Co, Zn and…

1984

Polymetallic solid solutions of the ethylenediaminetetracetic acid (EDTA) and six divalent metal ions exist in the range: MgαMnβCoγZnδNieCuτ(EDTA) · 6H2O where α + β + γ + δ + e + τ=2, 0⩽τ⩽1, 0⩽γ,e,δ⩽2, 0⩽α, β⩽1. This type of structure is characterized by the presence of two different octahedral carboxylate-bridged coordination sites forming infinite zig-zag chains. Visible and i.r. spectra and t.g.a. analysis show that there is occupational preference for the two coordination sites in the crystalline structure. Due to this preference, and also to the structural features, the heterobimetallic MM′(EDTA) · 6H2O compounds constitute a structurally new class of materials which can be described …

La signification économique du travail social

1984

International audience

Arsenic, antimony and bismuth complexation by L-cysteine in water

1984

Synthese, dans l'eau, des complexes L-cysteine: AsL 3 , SbL 3 •H 2 O et BiL 3 .H 2 O L=forme monoanionique de cysteine. Etude IR des structures

Comparative statistical studies on the physical anthropology of the late Medieval period (A.D. 1000–1500)

1984

Continuing previous studies on preceding temporal periods, a total of 162 skeletal series from the late Medieval period are analysed. The dendrogram reveals an east cluster as in the other periods but a west cluster is not evident possibly because western Europe is represented by very few series. Moreover, we find a Scandinavian and a Turk cluster. Regional or ethnic pooling of the original series gives an affinity structure which is more influenced by geographic proximity than by ethnic relation. This structure predominantly reflects differentiations of skull width and length and to a lesser degree of facial height. The diachronic trend appears again, but in this period there is only a sli…

PHOSPHORORGANISCHE VERBINDUNGEN 1081DIE SYNTHESE FLUORESZIERENDER UND CHEMOSELEKTIVER REAGENTIEN ZUM GEZIELTEN NACHWEIS UND SCHUTZ BIOLOGISCH WICHTIG…

1984

Abstract Compounds of type A are fluorescent, if the donator groups, like NMe2, OMe, SMe and PR2, and the acceptor groups, like R′P(O)X, SO2R′ and CO2R′, are linked to different nuclei of the naphthalin ring system.

L'éducation dans une nouvelle division temporelle des activités : raisonnement sur deux cas nationaux

1984

International audience

(8,9-Dihydro-7H-imidazo[1,2-c][1,3]diazepin-5-yl)-cyanamide und homologe imidazo-bizyklen

1984

Die Reaktion der 2-(ω-Aminoalkyl)-imidazole 4a-f mit N-Cyanodiphenyl-imidocarbonat (7) fuhrt zu den entsprechend hydrierten Imidazo[1,5-a]imidazolen, Imidazo[1,2-c][1,3]diazepinen und Imidazo[1,2-c][1,3]diazocinen (9a-f), die im Verhalten gegenuber Nucleophilen und in ihren spektroskopischen Eigenschaften den (7,8-Dihydro-imidazo[1,2-c]pyrimidin-5-yl)-cyanamiden (3) [1] vergleichbar sind. The reaction of the 2-(ω-aminoalkyl)imidazoles 4a-f with N-cyanodi-phenylimidocarbonate (7) leads to appropriately hydrogenated imidazo-[1,5-a]imidazoles, imidazo[1,2-c][1,3]diazepines and imidazo[1,2-c][1,3]diazocines (9a-f), which are similar to (7,8-dihydroimidazo)[1,2-c]pyrimidin-5-yl)cyanamides (3)[1]…

Über polygermane

1984

Abstract The optimum conditions for selectively cleaving off two phenyl groups in Ge2Ph6 by trichloroacetic acid have been determined. Neither trihaloacetic acids nor HCl/AlCl3 nor reactive tetrahalides MCl4 are suitable reagents for cleaving one phenyl group alone. The 13C NMR chemical shifts of functional phenyl-mono- and -digermanes are given. The crystal structure of 1,2-bis(trichloroacetate)tetraphenyldigermane has been determined and refined to R = 0.048. The digermane bond is bridged by both acetates (distances GeGe 239.3(2), GeO 207.3(3) and 231.4(3) pm). The Ge atoms have trigonal bipyramidal coordination.

Polycondensed nitrogen heterocycles. Part13. Pyrrolo[3,2-b]indole by intramolecular nucleophilic substitution reaction in the pyrrole series

1984

An intramolecular nucleophilic substitution in the pyrrole series has been generalized. The behaviour of nitro, chlorine, bromine and iodine as leaving groups towards the nucleophilic amino group was observed. An acid catalyzed mechanism has been proposed.

Computational analysis of positron experiments

1984

A number of applications of the calculational scheme developed by Puska and Nieminen (1982-3) are reported and the predictive power of the scheme is substantiated. Effects on positron parameters of relaxation and of N or H impurities in vacancies in Mo are calculated and employed to analyse recent experiments. Predictions pertaining to H decoration of vacancies in Al and Ni suggest the use of positron lifetime studies of these systems. Positron responses to submicroscopic vacancy clusters decorated with Kr and to large Kr bubbles in Cu are calculated and used to analyse recent experiments. To accomplish this the scheme is generalised to incorporate crystals of inert gas. In turn this makes …

Die ästhetische Wirkung von aus verschiedenen Perspektiven dargestellten Gesichtern

1984

In einer experimentellen Untersuchung wurden Fotografien von Gesichtern, die aus verschiedenen Perspektiven aufgenommen worden waren, von einem Beurteilergremium unter Verwendung einer Rating-Skala nach Schonheit beurteilt. Dabei ergaben sich signifikante Unterschiede zwischen den Beurteilungen fur die verschiedenen Bildvarianten. Daruber hinaus wurde festgestellt, das fur den Gesamteindruck die En-face- und Halbseitenansicht masgebender ist als die reine Profildarstellung.

Soluble groups which are products of nilpotent minimax groups

1984

Conditional Versus Joint Probability Assessments

1984

AbstractThe assessment of conditional and / or joint probabilities of events that constitute scenarios is necessary for sound planning, forecasting, and decision making. The assessment process is complex and subtle, and various difficulties are encountered in the elicitation of such probabilities such as, implicit violations ofthe probability calculus and some meaningfjilness conditions. The necessary and sufficient as well as meaningfulness conditions that the elicited information on conditional and joint probabilities must satisfy are evaluated against actual assessments empirically. A high frequency of violation of these conditions was observed in assessing both conditional and joint pro…

On the stability of bifurcation branches in thermal ignition

1984

A method is given to determine the stability of stationary solutions of the thermal ignition equation for the case ofn-dimensional spherical symmetry, together with the number of unstable modes. For sufficiently high temperature and activation temperature this number is arbitrarily large. Some numerical results on the solutions and their stability are reported.