ALBERT

Notes: Abstract The previously reported IR study on 21 different 1-substituted 3-acylamino-2-pyrazolines assumed thecis configuration for the amide groups. In order to establish the configuration, X-ray structure determinations of two model compounds (1-phenyl-3-benzoylaminopyrazoline, monoclinic,a = 5.218,b = 8.830,c = 14.372 Å, β = 90.7 °,Z = 2, P2 1; 1-benzyl-3-acetaminopyrazoline, monoclinic,a = 9.529,b = 13.679,c = 18.112 Å, β = 96.7 °,Z = 8,P21/n) were performed. Both structures were solved by direct methods, and refined to a finalR = 0.075 for 710 andR = 0.122 for 2140 observed reflections. The configurations of the amide groups were found to betrans.

Notes: Abstract The crystal structure of 2,4-dinitrophenyl phenylsulfide, C12H8N2O4S, has been determined by single crystal X-ray diffraction. The crystals are monoclinic, space groupP2 1/n, Z = 8, witha = 10.670(2),b = 8.381(4),c = 27.998(18) Å, and β = 100.44(4) °. There are two crystallographically independent molecules per asymmetric unit. All intensity measurements were made at room temperature on an Enraf-Nonius CAD-4 automatic diffractometer using monochromatized MoKα radiation. The structure was solved by direct methods and refined to a finalR value of 0.032. The two independent molecules have nearly identical geometries, with the most notable difference being the torsion angles involving the sulfur atoms. Thepara-nitro groups are more nearly in the planes of the central phenyl rings than are theortho-nitro groups although there may be nonbonded attractions between the latter. The two phenyls of each molecule are nearly at right angles to each other, as necessitated by steric forces involvingortho hydrogens. The characteristic distortions of the central phenyl rings caused by differing substituent electronegativities and degrees of conjugation are noted. The13C-NMR spectrum of the compound was assigned by comparison of calculated with observed chemical shift data. Calculated chemical shifts were obtained by incrementation of the chemical shifts of diphenylsulfide with standard nitro group additivities which were adjusted for the sulfur-nitro group interaction. Where necessary, assignments were confirmed with selective excitation spin-coupled subspectra. Solution behavior of the molecule was determined from spin-lattice (T 1) relaxation measurements which showed the unsubstituted ring to reorient anisotropically about the C(21)-C(24) bond axis while the substituted ring appears to be governed by the overall isotropic reorientation of the molecular framework, indicating that the sulfur-nitro group interaction restricts anisotropic reorientation about the C(11)-C(14) bond axis.

Notes: Abstract The reactions in THF or benzene between Cp2 M (HgX)2 ·x HgX 2 (M = Mo or W; O ⩽x ⩽ 1;X − = Cl−, Br−, I−, SCN−, OAc−) and sodium diethyl-dithiocarbamate $$\begin{gathered} Cp_2 M\left( {HgX} \right)_2 .xHgX_2 + \left( {2 + x} \right)Nadtc \rightleftharpoons Cp_2 M\left( {Hgdtc} \right)_2 \hfill \\ + xHg\left( {dtc} \right)_2 + \left( {2 + x} \right)NaX \hfill \\ \end{gathered} $$ as well as between Cp2 MH2 and mercury diethyldithiocarbamate $$x2Cp_2 MH_2 + 2Hg\left( {dtc} \right)_{2 - } Cp_2 M\left( {Hgdtc} \right)_2 + \left\{ {Cp_2 Mdtc} \right\}dtc + 2H_2 $$ give the compound Cp2 M(Hgdtc)2 (dtc is diethyldithiocarbamate anion). The structure of the molybdenum complex determined by the X-ray method (a = 12.776(4),b = 7.835(4),c = 27.397(7) Å β = 111.18(2) °; space groupC2/c (No. 15);Z = 4) consists of discrete molecules occupying special positions on two-fold axes. A short Mo-Hg distance of 2.643(8) Å and a rather long Hg-S one of 2.50(2) Å were found. The diethyldithiocarbamate anion behaves like a monodentate ligand. IR and1H,13C NMR results agree with the molecular structure determination and confirm a weak bond between mercury and dithiocarbamate and strong molybdenum-mercury bond. A considerable solvent effect (C6D6 vs. CDCl3 solutions) has been observed on the1H chemical shifts of both dtc and Cp ligands. The {Cp2Modtc}+ X − (X = dtc and PF6) complexes, although not obtained in a pure form, were included in the discussion of the spectroscopic features of those with theM-Hg bonds.

Notes: Abstract The crystal and molecular structure ofH 4a ,H 9a -cis-H 9,H 9a -trans-2-methyl-9-phenyl-2, 3,4,4 a ,9,9 a -hexahydro-1H-indeno[2,1-c]pyridine hydrochloride was determined. The compound crystallizes in the orthorhombic space groupPbca, with eight molecules in the unit cell of dimensionsa = 10.461(2),b = 20.141(10), andc = 15.469(3) Å. Intensity data were measured using Mo radiation and a θ−θ scan method. The structure was solved by direct methods and refined by least-squares techniques to a finalR of 4.6%. Thecis-trans isomer has higher antihistamine activity compared to thecis-cis isomer but is less active than phenindamine, the 2,3,4,9-tetrahydro derivative. The bond distances in thecis-trans andcis-cis derivatives are identical so that the differences in activity must be related to differences in conformation. The difference in the conformation is discussed from a receptor-site view of the two molecules.

Notes: Abstract The crystal structure of the muscle relaxant stercuronium iodide in the form of its ethanol solvate C26H43N2 +I− · C2H5OH, has been determined by the heavy-atom method and refined by block-diagonal least-squares toR o = 0.062 for 1941 observed reflections andR = 0.079 for a total of 2420 reflections measured on a four-circle diffractometer in the ω/2θ scanning mode. The crystals are monoclinic,P21,a = 15.386(5),b = 11.377(4),c = 8.307(3) Å, β = 98.22(2) °,Z = 2. RingsA andB in the modified conessine skeleton are both highly symmetrical half-chairs, ringC is in the chair conformation, and ringsD andE are highly symmetrical envelopes. The pyrrolidine ringE fused to ringD is roughly perpendicular to the steroid skeleton formed by ringsA toD. The N+---N distance of 10.76 Å is within the usual range required for potent neuromuscular blocking. Semiquantitative results are presented which suggest that the site of the tertiary N atom in ringE is not heavily congested by neighboring atoms in the molecule and may therefore be susceptible to protonation under physiological conditions. This could account for the relatively high drug potency of stercuronium.

Notes: Abstract The crystal structure of 2-aminophenol has been redetermined from automatic diffractometer data in order to locate the hydroxyl and amino hydrogens and confirm the nature of the intermolecular hydrogen bonding. Crystals are orthorhombic, space groupPbca, witha =19.751(6),b = 7.250(3), andc = 7.852(5) Å, and eight molecules per cell. The structure was solved by Multan and refined to a conventionalR value of 0.030. The molecular geometry compares well with previously reported structures of related species. The molecules are hydrogen bonded from OH to N to form chains parallel to theb axis, with these chains linked together to form sheets by NH to O hydrogen bonds essentially parallel toc. The NH - O hydrogen bonds are 0.33 Å longer than the OH - N ones, and an explanation for this is provided which incorporates newly computed values for atomic electronegativities. Pairs of molecules are mutually hydrogen bonded across inversion centers. There are large cavities between the sheets which could conceivably result in easy intercalation of small foreign molecules, much as in the clathrates formed by urea and β-quinol.

Notes: Abstract Crystals of 5-ethyl-5-(3′-methylbut-2′-enyi) barbituric acid, mp 154° C, are monoclinic, space groupP21/c witha = 11.590(3) Å,b = 22.188(10),c = 10.195(4), β = 108.949(1)°, and Z = 8. The crystal structure was solved by direct methods and Fourier and difference-Fourier techniques, and refined by block least-squares procedure toR = 0.071 for 2983 observed data. Of the two molecules in the asymmetric unit, one is disordered and has been explained in terms of three different conformations of the 3′-methylbut-2′-enyl group. The molecules form ribbonlike structures, held together by N-H ... O=C hydrogen bonds. These ribbons are held together to form bilayers of barbiturate rings by van der Waals interactions between the 5-ethyl groups, with the bilayers held together by van der Waals interactions between the 5-(3′-methylbut-2′-enyl) groups.

Notes: Abstract The crystal structure of bromofluoroacetic acid has been determined from three-dimensional counter data, and refined by full-matrix least-squares techniques. The crystals belong to the monoclinic space groupP21/c, witha = 8.529(4),b = 5.632(3),c = 9.500(4) Å,β = 105.52(4) °, andD x = 2.37 g cm−3 forZ = 4. The finalR factor for 654 independent observed reflections is 0.081. The compound exists as hydrogen-bonded dimers in the solid state.

Notes: Abstract trans-5-Ethyl-5-but-1′-enyl barbituric acid, mp 112° C, is triclinic, space groupP¯1 witha = 8.228(1),b = 10.445 (2),c = 7.265(1) Å, α = 111.165(1), β = 105.512(1), γ = 95.079(1)°, and Z = 2. The crystal structure was determined by direct methods and refined to R = 0.047 by full-matrix least-squares procedures for 2308 observed diffraction maxima. The molecules form ribbonlike structures alongb, held together by N-H ... O=C hydrogen bonds and van der Waals forces between an alternating sequence of ethyl and but-1-enyl groups.

Notes: Abstract Crystals oftrans-5-ethyl-5-(1′,3′-dimethylbut-1′-enyl) barbituric acid (13M1TB), mp 183° C, are triclinic witha = 7.677(2),b = 10.393(3),c = 9.176(3) Å, α = 104.331(1), β = 106.919(1), γ = 96.494(1)°, space group P, with two molecules in the unit cell. The structure was solved by direct methods and refined by least-squares procedures toR = 0.050 for 2809 observed diffraction maxima. The 5-ethyl group is oriented under the barbiturate ring with the orientation of the but-1-enyl group directed away from the ring. This orientation is determined by the 1′-methyl substituent. The molecules are linked together by N-H ... O=C hydrogen bonds across inversion centers, thus forming single ribbons alongb. Adjacent ribbons are held together in theac plane by van der Waals interactions between alternating ethyl and l′,3′-dimethylbut-l′-enyl groups.

Notes: Abstract The distance between two equilibrium proton sites in symmetric OHO bonds and its isotopic variation, determined from precise neutron-diffraction data, has been compared with the predicted values which were derived previously by the author using correlation curves in hydrogen-bond parameters. It is shown that a fairly good agreement was obtained between the observed and the predicted values, indicating the validity of the empirical relations.

Notes: Abstract The crystal structure of vanadocene has been determined from counter data, and refined by full-matrix least-squares techniques. The crystals belong to the monoclinic space groupP21/n witha = 9.269(3),b = 8.020(3),c = 5.892(2) Å, β = 91.21(3)°, andD x = 1.37 gcm-3 for Z = 2. The finalR value for 583 observed reflections is 0.031. The vanadium atom resides on a crystallographic center of inversion. The cyclopentadienyl groups are statistically disordered 70–30%. The average vanadium-carbon (η5) bond distance is 2.26(2) Å.

Notes: Abstract Crystals of C20H16N2O2 are orthorombic:P212121,a = 28.1364(21),b = 7.6474(2),c = 7.5376(2) Å,Z = 4, μ = 6.4 cm−1 (CuKα radiation), andM = 316.36. The structure has been solved by direct methods and refined by two-block least-squares toR = R w = 0.042. The conformation of ringB is a distorted envelope at N(10), and the phenyl rings have acis configuration with respect to the pyridazine ring. Thermal motion of the molecule has been analyzed in terms of the rigid-body TLS model.

Notes: Abstract Crystals of the title compound, C17H14BrNO, are monoclinic, with space groupP21/a,a = 14.314(5),b = 15.009(11),c = 6.596(3) Å, and β = 102.39(3) °. Diffraction data were collected with CuKα radiation to a Bragg angle of 77 °. The structure was solved by the heavy-atom method and refined to anR index of 0.059 for 2129 reflections. In agreement with NMR results, the C=O group is orientedanti to the benzene ring, and the methyl group at C(6) is axial. Unlike 1-(p-bromobenzoyl)-2-methyl-1,2,3,4-tetrahydroquinoline, the heterocyclic ring assumes a well defined half-chair conformation. Except for C(5) and the methyl group at C(6), the whole molecule is very nearly planar.

Notes: Abstract The X-ray crystal structure of the title compound, C10H14S1, is reported. Crystals are monoclinic, space groupP21/c with Z = 2 in a unit cell of dimensionsa = 8.517(2),b = 6.109(1),c = 10.730(1) Å, and β = 107.01(2)°. The structure was solved by direct methods and refined by full-matrix least squares toR = 0.032 for 1059 diffractometer data. The bicyclic molecular framework contains eight π-electrons and is planar and rigid, all relevant interatomic distances corresponding to either ideally single or ideally double bonds. The first UV absorption observed at 3.61 eV, and tentatively described as due to a π(bg) → π*(a u*) electron transition, is significantly higher than that found in a related aromatic tetraphenylthienothiophene system.

Notes: Abstract Crystals of the phenylurethane derivative of a novel bicyclic lactone, C18H21NO8, have an orthorhombic unit cell of dimensionsa = 8.648(2),b = 11.041(7),c = 19.589(4) Å, and belong to space groupP212121. The structure was solved by direct methods and was refined by the block diagonal approximation to a finalR value of 0.034 using 1035 reflections. The structure is made up of a six-membered lactone ring, in the boat conformation,cis-fused to a five-membered oxolane ring. The phenylurethane and the methoxy groups aretrans to each other, while the ethyl carboxylate group is attached in equatorial position.

Notes: Summary Floor Loading and Movement Along the Coalface Total roof to floor convergence, floor loading, horizontal and vertical movements of floor along three selected longwall faces were investigated. Empirical equations expressing the above noted linearly time-dependent factors in strata mechanics are developed. It was observed that the contribution of floor to the total roof to floor closure is between 31 to 63%, dependent upon the strength of roof and floor layers encountered.

Notes: Résumé Anisotropie de la dilatance des roches schisteuses Les petites déformations de schistes ardoisiers, mesurées au cours d'essais de compressions triaxiales, montrent une orthotropie de révolution élastique initiale dont les coefficients varient avec la pression de confinement. Lorsque la déformation croît, comme pour les roches pseudo-isotropes, mais seulement pour certaines plages d'orientation de la structure par rapport au tenseur contrainte, prend naissance le mécanisme de dilatance. Le seuil de dilatance dépend de cette orientation et de la pression de confinement. La dilatance croît avec la contrainte suivant une loi proche du second degré.

Notes: Summary On the Determination of Some Important Geotechnical Joint Properties by Means of Integral Geometry Simple equations are presented which are useful to evaluate properties of joints important in rock mechanics, e. g. the length of linear of intersected joints, the joint area, the joint opening, the joint volume, and the edge length of rock blocks defined by joints. Also, the integral-geometrical derivation of the equations is presented to compare these with previously published expressions for such joint properties. Methods of measurement are illustrated to record the features from which the joint properties are evaluated: simply determinable numbers of points and lengths along measuring lines and numbers of points on measuring areas. The potential usefulness of the integral-geometrically derived equations is tested on a weathering profile of a Upper Devonian siltstone.

Notes: Summary Approach to Complete Limit Equilibrium Analysis for Rock Wedges — The Method of “Artificial Supports” Since the movement of rock wedges or blocks is the primary phenomenon in rock mass failure, it is convenient to use limit equilibrium approaches for stability analysis. In spite of their wide use, limit equilibrium analysis is often restricted due to: 1) the usual procedural simplifications (regarding geometry, force application, failure modes), and 2) basic deficiencies of the limit equilibrium approach (the fundamentally indeterminate rigid body problem requires assumptions regarding the force reactions). The method of artificial supports intends to circumvent or reduce many of these restrictions. In particular, the problem of unknown force distribution on the supporting plane is reduced by specifically considering and optimizing a variety of reactions on these planes. All sliding modes of failure — i. e., translational, free and restrained rotational sliding — can be correctly modelled. Particularly significant is the result that the usual assumption oftranslational sliding can be incorrect andunsafe, if forces other than the weight are significant. The methodologies employed in the artificial support model can be extended to all modes of failure, i. e., lifting off and toppling in addition to the previously mentioned sliding modes; this is demonstrated with a procedure for a “complete” stability analysis for a 2-joint wedge.

Notes: Zusammenfassung Das neotektonische Spannungsfeld in den Regionen von Shaanxi, Gansu, Ningxia und Qinghai (China) Geologische, seismologische, geodätische und geomorphologische Daten wurden verwendet, um die Richtung der überregionalen, neotektonischen Hauptnormalspannungen im nördlichen Zentralchina zu bestimmen. Es wird gezeigt, daß die maximale Druckspannung eine NE-SW-Richtung hat (N 40° E). Im Detail scheint es eine Rotation der maximalen Druckspannungsrichtung von N 7° E im Ladakh bis N 33° E im chinesischen Westxizang und bis ca. N 70° E im Südwesten der hier untersuchten Region zu geben. Dies kann ein Hinweis dafür sein, daß, abgesehen vom Effekt einer Kollision zwischen der eurasischen und indischen tektonischen Platte, sich auch der Effekt der Kollision zwischen der eurasischen und pazifischen Platte bemerkbar macht.

Notes: Summary Size Distributions of Rock Blocks from Measurements on Rock Faces In this model rock blocks are regarded to have spherical shape and they are described by a distribution of diameters of spheres. The measured quantities are the lengths of chords which are recorded along measuring lines across rock faces. The volume fractions of the size classes of rock blocks are derived from the distribution of chord lengths. Three methods are discussed for obtaining the sphere diameter distribution from counts of chord numbers on sections. An example is given for the size distribution of rock blocks in a weathering profile of an Upper Devonian siltstone.

Notes: Zusammenfassung Geomechanische Modelluntersuchungen für die Gründung von Talsperren Das Verhalten hoher bestehender Talsperren für Großspeicher, einige besondere Vorkommnisse bei der Nutzung derselben sowie einige Unfälle haben gezeigt, daß der Frage der Gründung von Talsperren besondere Bedeutung zukommt, da ein einwandfreies Zusammenwirken von Sperrenkörper und Gründungskörper für die potentiellen Lastfälle Voraussetzung für die Standsicherheit von Talsperren ist. Somit wird die Frage der Gründung von Talsperren bereits im Planungsstadium zu einem wesentlichen Bestandteil jeder ernsthaften Projektierung. Bei der Ausarbeitung von Alternativlösungen für den Talabschluß eines Speicherbeckens kann diese Frage sowie die Beurteilung des künftigen Verhaltens des Untergrundes der Sperre und des Speicherbeckens für die Dauer der vorgesehenen Nutzung die Wahl eines Sperrentyps maßgebend beeinflussen. Während wir für den Sperrenkörper mit Baustoffen arbeiten, deren Festigkeitsund Verformungseigenschaften wohlbekannt sind, ist dies für den Sperrenuntergrund, auch bei sorgfältig durchgeführten Voruntersuchungen und Aufschlußarbeiten während der Bauzeit nicht der Fall und auch nicht zu erwarten. Rechnerische und experimentelle Untersuchungen zur Erfassung des wahrscheinlichen Verhaltens des Untergrundes für ein Speicherbecken werden unter diesen Voraussetzungen in den meisten Fällen mit Schwierigkeiten behaftet sein; diese nehmen mit der Höhe der Talsperre als auch mit der Größe des Speicherraums zu. Die heute in der Talsperrenstatik üblichen Berechnungsmethoden, die das Untergrundverhalten in die Betrachtung mit einbeziehen, sind keineswegs so, daß sie als vollbefriedigend angesehen werden können. Über diese Tatsache kann auch der Einsatz von hochgezüchteten, für geomechanische Betrachtungen mehr oder weniger geeigneten Computerprogrammen beim Entwurf von Talsperren nicht hinwegtäuschen. Anhand von Prinzipskizzen von Talsperren verschiedener Typen wird die Frage der Kraftübertragung vom Sperrenkörper in den Untergrund im Zusammenhang mit den damit verbundenen Problemen erläutert, sowie auf die Grundzüge der bei der Planung von Sperren gebräuchlichen Berechnungsverfahren (mathematische Modelle) eingegangen. Der Aussagewert dieser Berechnungen im Hinblick auf die Beurteilung des Tragvermögens des Sperrenuntergrundes ist begrenzt und trägt — der Problemlösung inhärent — Zeichen einer ingenieurmäßig fundierten Abschätzung. Ein weiteres wertvolles Hilfsmittel für die Problemlösung steht dem planenden Ingenieur mit der Anwendung geomechanischer Modelluntersuchungen zur Verfügung. Bei Untersuchungen dieser Art werden das Gefügesystem (Groß- und Kleinklüfte) und Störungen im Felsuntergrund unter Berücksichtigung der Gefügeeigenschaften nachgebildet. In Abhängigkeit von den Anforderungen, dem Arbeitsaufwand und der angewandten Versuchstechnik wird die Qualität der Ergebnisse derartiger Untersuchungen sein. In vielen Fällen wird die Aussage nur qualitativen oder bestenfalls halb-quantitativen Charakter haben, jedoch in sehr anschaulicher Weise, z. B. potentielle gefährliche Verformungsvorgänge aufzeigen. Hauptsächlich dadurch sind sie ein wertvolles Hilfsmittel für den Entwurf, sowie für konstruktive und meßtechnische Entscheidungen. Je nach Aufgabenstellung werden derartige Versuche zweioder dreidimensional durchgeführt. Anhand einiger Beispiele werden die Einsatz- und Aussagemöglichkeiten von geomechanischen Versuchen erläutert, auf Entwicklungsmöglichkeiten bei der Anwendung sowohl für die Grundlagenforschung als auch für die projektbezogene Forschung wird hingewiesen. Abschließend wird festgestellt, daß die Bedeutung geomechanischer Untersuchungen in unserer Zeit des Computers nicht übersehen werden darf, da geeignete Berechnungsverfahren und adäquate Modelluntersuchungen als notwendige und gleichwertige, sich ergänzende Partner zu betrachten und heranzuziehen sind, um schwierige und verantwortungsvolle Entscheidungen bei der Errichtung von hohen Talsperren mit größtmöglicher Sicherheit treffen zu können; dies war grundsätzlich immer so, ist aber mit einer gewissen Euphorie der „allmächtigen“ Computer mancherorts in Vergessenheit geraten. Die Komplexität der Problemlösung einerseits und die der Verantwortung für ein einwandfreies Verhalten von Talsperren andererseits lassen die Notwendigkeit der Heranziehung aller bewährten Hilfsmittel zur bestmöglichen Erfassung der vielfältigen Aspekte der Problemstellung erkennen, um damit den Spielraum der Unsicherheiten in der Beurteilung der Standsicherheit einer Talsperre weitgehend einzuengen.

Notes: Summary The lower ultramafic part of the Chalkidiki Ophiolite Complex consists of a successive alternation of chromitite, dunite, and harzburgite, which is repeated periodically in a cyclic manner. This cyclic pattern is consistent with an origin as magmatic cumulates. However, the tectonic fabric superimposed on the cumulate texture of this sequence suggest a solid-state deformation at considerable depth. In the present study, the textural and chemical features of chromite are discussed. The interrelationships between the compositions of chromite, its mode of occurrence as well as the associated silicates are emphasized. It is found that the investigated chromites have properties in common with both podiforn and stratiform chromites. From a geometrical and structural point of view, they are of podiform type. On the other hand, their appreciably high iron content, the strong interdependence between the composition of chromite and the coexisting silicates together with the cryptic layering exhibited by the two mineral groups contrast markedly with podiform chromites. An alternative hypothesis is proposed involving fractional crystallization of an ultrabasic melt introduced to the magma chamber as periodic inflows of essentially the same composition. An upwelling upper-mantle that is subjected to stepwise partial fusion may fulfill these conditions.

Notes: Summary Au-and PGE-bearing samples1 from organogenic limestone located in the western part of the Lubin mine have been investigated. They contain: Au−Ag−Pt−Hg alloys, native Pd, sobolevskite (PdBi), native lead and plumbian gold which is related to an admixture of AuPb2, electrum (Ag2Au). Clausthalite also occurs in this association and contains up to 1% Ir. Kerogen is an important member of the association and contains, among others, 700 ppm Pt, 400 ppm Pd, 600 ppm Ir and 1100 ppm Au. These alloys are closely associated with nests of secondary calcite with dark brown internal reflections due to admixture of organic compounds. Organic matter colouring calcite II contains: ketones (chiefly diketones), nitrogen derivatives, phenols, probably tertiary alcohols and aromatic hydrocarbons. Metal carbonyls were also recorded. The organic substances investigated contain oxidation retarding derivatives.

Notes: Summary The mineral fibroferrite has the chemical formula Fe(OH)SO4·xH2O; the value forx has not been definitely settled, but as a rule it is found to be near five. Several symmetries are given in the literature. A sample from Saint Felix de Paillères, France, proved to be rhombohedral with space group R3; lattice constants for the hexagonal cell area=24.176,c=7.656 Å. As calculated from the experimental density (ρ=1.95 g·cm−3)Z=18 for this cell. Intensities were collected on an automated X-ray diffractometer from a thin fiber extended along [00.1]. The structure was determined by Patterson and Fourier methods. Least squares refinement with 818 observed reflections resulted inR=0.076. The structure contains hydroxo-bridged {Fe(OH)(H2O)2SO4} spiral chains built of [Fe(OH)2(H2O)2O2] octahedra and SO4 tetrahedra. Hydrogen bonds provide connections between these chains. The spiral chains are a stereoisomer variant of the hydroxo-bridged linear chains of Fe(OH)SO4, butlerite and parabutlerite. A comparison of these compounds is givenm to understand the relationship between the structure and their water content.

Notes: Zusammenfassung Die Kristallstruktur des Tunisits wurde zunächst an Material vom Originalfundort prinzipiell bestimmt; in Übereinstimmung mit einer neuen Analyse ergab sich eine Änderung der chemischen Idealformel auf NaCa2 Al4(CO3)4(OH)8Cl. Die Strukturverfeinerung erfolgte an dafür besser geeignetem Material aus Frankreich; mit 692 kristallographisch unabhängigen Röntgenreflexen wurde ein konventioneller ZuverlässigkeitsindexR=0,059 erreicht. Die Atomanordnung stellt einen neuen Strukturtyp mit [Al[6](OH)2 CO3]1−-Schichten parallel zu {001} dar. Die Na-Atome sind von vier O-Atomen und einem Cl-Atom koordiniert. Um die Ca-Atome wurde eine (4+2+4)-Koordination von Sauerstoffen gefunden; da sich für dieses Atom ein stark ausgelängtes Schwingungs-ellipsoid ergab, scheint eine Aufspaltung der Ca-Punktlage um ca. 0,4 Å möglich.

Notes: Zusammenfassung Der Grad der frühalpinen Metamorphose im Schneebergerzug und angrenzenden Altkristallin ist charakterisiert durch die beginnende Stabilität von posttektonisch gewachsenem Staurolith und Disthen am Nordrand des Schneebergerzuges. Das erste Auftreten von Staurolith ist durch erhöhten ZnO-Gehalt im Gestein kontrolliert, der im Staurolith mit maximal 5,6 Gew.% konzentriert ist. Erst südlich des Schneebergerzuges werden die Temperaturbedingungen der disk ontinuierlichen Mineralreaktion Granat + Chlorit + Muskovit = Staurolith + Biotit + Quarz + H2O überschritten. Die Staurolithbildung in paragonitreichen Schiefern wird der Mineralreaktion Paragonit + Chlorit + Quarz = = Staurolith + Albit + H2O zugeschrieben. Die häufige stabile Paragenese Paragonit + Quarz im chemisch reinen System limitiert die Maximaltemperaturen der frühalpinen Metamorphose mit einer thermodynamisch berechneten Temperatur von 570°C (5 kb). Mischkristallbildung, die im Albit stärker ist als im Paragonit und Verdünnung der Gasphase in Graphit-haltigen Gesteinen führte zur Instabilität von Paragonit und Quarz bei deutlich tieferen Temperaturen. Der Mg/Fe-Verteilungskoeffizient zwischen Granat und Biotit in bivarianten Paragenesen des Schneebergerzuges wird um einen Wert von 0,003 pro Mol.% Grossularkomponente im Granat erniedrigt. Die Verteilungskoeffizienten werden für diese Beeinflussung korrigiert und ergeben Gleichgewichtstemperaturen zwischen 548° und 577°C (5 kb). Eine weitere Erniedrigung des Verteilungskoeffizienten von Mg/Fe zwischen Granat und Biotit ist in Paragenesen mit zinkreichem Staurolith zu beobachten. Das Auftreten von Disthen läßt auf einen Mindestdruck während der frühalpinen Metamorphose von ∼5 kb bei 570°C schließen.

Notes: Summary Kutnohorite-quartz veins penetrate through a weakly metamorphosed Late Proterozoic sedimentary rhodochrosite carbonate in pyrite shales. Kutnohorite is pleochroic ranging from colourless (∈) to pinkish grey (ω), ω=1.735, ∈=1,543,d=3.066g·cm−3;a 0=4.852(1),c 0=16.219(7) Å. A quantitative chemical analysis leads to the formula (Ca0.95Mn0.05)1.00(Mn0.64Mg0.23Fe0.13)1.00(CO3)2.04. An electron microprobe scanning reveals considerable microscale inhomogeneity in cleavage rhombohedrons taken from a coarsely grained aggregate. It is mostly of the character of periodic fluctuations of the main element contents around an average value. There is a strong prevalence of an Fe+Ca−Mn+Mg antagonism, the extremes of compositonal differences lying in distances of 0.0X mm. The fluctuation maxima amount to about 9% for FeO, 6% for MnO, 3% for CaO, and 1.5% for MgO. In one of the samples even a two phase character with the above antagonism between the two phases was detected by X-rays. The inhomogeneities are due, partly at least, to the Fe-metasomatic processes that followed the formation of the kutnohorite by Alpine-paragenesis hydrothermal metamorphism.

Notes: Summary The crystal structure of låvenite (monoclinicP2 1 /a,a=10.83(1),b=9.98(1),c=7.174(5) Å, β=108.1(1)o), was refined using 1743 independent reflections toR=0.032 andR w=0.036. The refined structure is in agreement with the structure model proposed bySimonov andBelov (1960), characterized by the presence of walls of large cation polyhedra. These walls are four columns large, linked together by both direct connection as well as by Si2O7 groups. The cation distribution inside the wall is explained and compared with that found in other phase of the cuspidine group. The crystal chemical formula resulting from structural and chemical analyses on låvenite from Langesund (Norway) is (Na6.50Ca1.47Y0.03) (Ca0.93 Mn1.26Fe 0.87 2+ Ti0.65Zr0.18Mg0.05) (Zr3.42Nb0.58) (Si2O7)4O3.82F3.98.

Notes: Summary The Middle Proterozoic Faraday Metagabbro in the Bancroft area of eastern Ontario has been subjected to syn-orogenic textural and mineralogical modifications resulting in the formation of scapolite-bearing metagabbro and gabbroic blastomylonite assemblages. The elemental flux during cryptic and overt scapolitization has been calculated usingGresens general metasomatic equation which applies corrections for density and volume changes during alteration. Metasomatic variation diagrams using analyses from two primary gabbros and six altered rocks indicate that Na, K, Cl, Li, Rb, and Ba are the principal introduced elements and that Cu and S were removed. These changes are very similar to those involved in the formation of metasomatic nepheline-bearing rocks elsewhere in the district and, furthermore, nephelinization and scapolitization were broadly coincident in time and space. It is concluded that the nephelin- and scapolite-bearing rocks and their cryptic facies are different manifestations of the same metasomatic agent and that the source of the fluids was a possible horizon of evaporitic sediments within the country rocks in which the gabbro was emplaced.

Notes: Zusammenfassung An sieben Pegmatiten aus der Kor- und Saualpe wurden insgesamt 12 Rb−Sr-Gesamtgesteins-Analysen durchgeführt, an Muskoviten aus den Pegmatiten sind 16 Rb−Sr-Analysen und 15 K−Ar-Bestimmungen gemacht worden. Alle Pegmatite haben zwei Hellglimmergenerationen, die deutlich unterscheidbar sind. Mit der Rb−Sr-Methode ergeben die großen Muskovite (bis 20 cm ϕ) in acht Fällen praealpidische Alterswerte: 240 bis 265 M, J. Mit der gleichen Methode wird an den Muskoviten der zweiten Generation (bis 3 cm ϕ) alpidisches Alter bestimmt: 72 bis 122 M. J. Die Rb−Sr-Gesamtgesteins-Analysen deuten auf ein geöffnetes System für Rb−Sr in alpidischer Zeit, vergleichbar mit den Paragneisen (Morauf, 1980b). Die K−Ar-Bestimmungen an den Muskoviten beider Generationen ergeben alpidische Alterswerte; 71–116 M. J. Es ist ein Einfluß der Korngröße auf den Alterswert feststellbar sowie Unterschiede zwischen Kern und Rand bei den Muskoviten der ersten Generation. Prae-alpidische Mineral-Alter sind im Bereiche der Kor-und Saualpe nur noch in großen Pegmatit-Muskoviten nachweisbar, da durch eine altalpidische druckbetonte Metamorphose (vor 80 M. J.) nicht nur kleine Glimmer verjüngt/gebildet wurden, sondern auch die Gesamtgesteine zum teilweise offenen System für Rb und Sr wurden. Die prägende Deformation muß nach den vorliegenden Daten ebenfalls altalpidisch sein.

Notes: Summary This paper deals with some unsolved crystal chemical questions concerning a group of alkali iron hydrated sulphates based on clusters of composition [Fe 3 3+ O(SO4)6(H2O3]5− Taking the experimental chemical formulae, X-ray data and known crystal structures into account it is possible to establish the theoretical boundaries of the Na−K diadochy in metavoltine and also to define the influence of the Na−K replacement on the structure of α-Maus' salt. These considerations allow us to propose more general crystal chemical formulae, both for metavoltine and α-Mous' salt. Finally, the causes which affect the stability of metavoltine and α and β-Maus' salt are discussed.

Notes: Zusammenfassung Es werden die hydrothermalen Alterationen der subvulkanischen dazitischen Andesite-stellenweise mit Monzoniten und Monzodioriten vergesellschaftet — in einem Gebiet nördlich und nordöstlich von Kirki mineralogisch-petrographisch und chemisch untersucht und ihre Beziehungen zu den sulfidischen Vererzungen diskutiert. Sie werden schematisch wie folgt aufgeschlüsselt: 1. Eine hochthermale Alteration führte zur Bleichung und zu starken chemischen Veränderungen des Gesteins, das durch Albitisierung, Serizitisierung und Verkieselung gekennzeichnet ist. Hiermit ist eine Erzmineralisation des “porphyry-Typs” aus Molybdänit, Kupferkies und Pyrit verbunden. Um das gebleichte Gestein ist der dazitische Andesit propylitisiert. In diesem Umwandlungsstadium treten Chlorit, Epidot, Karbonate, Prehnit und Zeolith auf. 2. Nach der Intrusion des dazitischen Andesits erfolgte eine tektonische N−S bzw. NNW-SSE gerichtete Gangbildung, und es wurde die sulfidische Gangmineralisation, zunächst mit Sphalerit, eingeleitet. Die Hauptphase der Pb−Zn-Vererzung (Bleiglanz und Fe-freier Sphalerit und Wurtzit) fand jedoch im epi- bis telethermalen Stadium statt. Der gleiche Vulkanismus und ähnliche Alterationen sind auch in benachbarten Gebieten am SE-Rand der Rhodopen anzutreffen. Es wird insbesondere auf die Bedeutung der Bleichungshöfe und ihrer Erzmineralisation des “porphyry copper Typs” hingewiesen.

Notes: Summary The hydrogen content of 29 quartz crystals originating from the Penninic series of the central and western Tauern Window (Tyrol, Austria) was determined by IR spectroscopy. The hydrogen contents are between 7 and 66 H/106 Si-atoms. In one sample showing a mimetic lamellar structure H-contents up to 140 H/106 Si-atoms could be found. In most cases no difference exists between the hydrogen contents of margins and cores of the crystals. No clear relationships between the hydrogen content of the quartz lattice and the metamorphic temperature ranging from about 600°C to about 450°C can be found.

Notes: Summary Pressure/temperature estimates based on different combinations of calibrated mineralogical thermometers and barometers and alternative assumptions concerning the Fe2+/(Fe2++Fe3+) ratios in the mineral phases are compared for a suite of fourteen nodules. PreferredP/T values have been obtained by simultaneous solution of eq. (12) ofWood (1974) for garnet-orthopyroxene equilibria and theEllis andGreen (1979) equation defining theP,T,X dependence of the Fe2+−Mg2+ partition coefficient for coexisting garnet and clinopyroxene. However, to obtain realistic results it is first necessary to calculate the Fe3+ contents in the minerals—conveniently done on a charge balance basis. The favoured meanP/T estimates of 654±36°C and 10.8±3.1 kbs are compatible with a lower crustal origin for this nodule suite.

Notes: Summary Changes in morphology of the parent solid materials, and the texture of kaolin crystals developed during hydrothermal synthesis of kaolin, may be graphically followed by scanning electron micrography (SEM) of the samples drawn during synthesis. Because the chemical conditions prevailing during synthesis are controlled and known, a possiblity arises for correlating the type of kaolin texture that is produced with the various known properties of the genetic environment. In this study, which is a first attempt toward that objective, the texture of kaolin produced by four different variations of hydrothermal synthesis using amorphous silica, allophane, and gibbsite in H2SO4 and H4EDTA solutions are illustrated with SEMs. Elongate crystals of kaolin, and accordion-type mats of elongate crystals, not plates, interspersed with less dense layers of elongates are recorded.

Notes: Summary Thermal metamorphism and later retrogression of low metamorphic grade garnet-bearing pelites has produced diverse patterns of garnet zoning. In the narrow thermal aureole, fibrolite, staurolite and biotite are present and commonly are retrogressed to assemblages containing sericite, chlorite and chloritoid. In the thermal aureole, garnet contains inclusions of quartz, biotite, fibrolite, ilmenite, chlorite and muscovite and underwent relatively rapid growth from pre-existing low to medium grade regionally metamorphosed rocks. Garnet was armoured from breakdown reactions by fibrolite which nucleated on garnet. The grain size of poikiloblastic garnet, the volume of zones of inclusions in the garnet and the size of the inclusions all decrease with increasing distance from the contact. In the thermal aureole, normal compositional zoning is common and rare reversezoned garnets probably result from the partitioning of Mn from ilmenite during thermal metamorphism. Garnet grains in the thermal aureole have a peripheral enrichment in Mn in the outermost 200 μm as a result of diffusion of Fe from garnet into the matrix during incipient retrogression. Coarse retrograde garnet in schists is unzoned and richer in Fe than the normal- and reverse-zoned prograde garnet in hornfelses suggesting that relatively large scale local diffusion in retrograde schists was operative during retrogression but not effective enough to completely remove the relic prograde zoned garnets in the hornfelses.

Notes: Summary The green feldspar in alkali granite from the Avdar deposit of decoration stone (150 km W of Ulan-Bator) has been identified by means of physical and chemical methods as amazonite. Its structural state corresponds to that of microcline with a high degree of triclinicity and displaying the following anomalous dimensions of the unit cell (nm):a=0.8568,b=1.2967,c=0.7217 nm, α=90.732, β=115.851, γ=87.702°;V=0.72115 nm3. The amazonite contains in increased amount of Pb (1950 ppm) as well as of Rb (1.15 mass %). The genesis of this amazonite is associated with younger metasomatic processes in the alkali granite.

Notes: Summary Recently several natural and artificial ferric iron sulphate crystal structures have been solved. Sideronatrite, Na2Fe3+(SO4)2(OH)·3H2O, does not provide good crystals for structural purposes. However if we examine crystallographic, chemical and physical data some useful information about the ...Fe−O−S... structural topology can be inferred. In fact this analysis strengthens the hypothesis that there is a {Fe 2 3+ (SO4)4(OH)2} chain in sideronatrite like that found in guildite, Cu2+Fe3+(SO4)2(OH)·4H2O.

Notes: Zusammenfassung Die intermediären bis basischen Plutonite des Nördlichen Waldviertels aus dem Raum Gebharts-Pfaffenschlag werden petrologisch untersucht und ihre Genese sowie ihr möglicher Zusammenhang mit den großen granitischen Intrusionen dieses Bereiches diskutiert. Nach Mineralbestand und Chemismus können diese basischen Gesteine im Wesentlichen als Quarzmonzodiorite und Quarzmonzonite klassifiziert werden. Es wird gezeigt, daß diese Plutonite trotz variablem Chemismus einen weitgehend ähnlichen Entwicklungstrend aufweisen. Die Kristallisationsfolge beginnt je nach Ausgangschemismus mitOpx undKpx; mit steigendemP H2O erfolgte eine vollständige Uralitisierung der Pyroxene unter Bildung von Anthophyllit oder Mg- und Ca-Amphibolen. Der Abbau von Cummingtonit zu Biotit sowie die Verdrängung von Korund durch Margarit und die Bildung von Diaspor aus Spinell in Resorptionsschlieren spricht für eine langsame Abkühlrate unter kontrolliertenP H2O-Bedingungen. Die untersuchten dioritischen Gesteine werden aufgrund ihrer tieftemperierten Umwandlungsreaktionen als synorogene Intrusionen angesehen, wobei einP H2O ≃ 3 kb ≤P total bei einer angenommenen H2O-Sättigung der Schmelze einer Mindestintrusionstiefe von 12 km entspricht. Geochemisch sind die untersuchten Massengesteine anhand einiger Element-Quotienten von Krustenmaterial abzuleiten, wobei aber eine Beteiligung von Mantelmaterial nicht ganz ausgeschlossen werden kann. Die Haupt- und Spurenelementgehalte zeigen eine klare Entwicklungstendenz vom Gabbro von Kleinzwettl über Hornblende- und Biotitdiorite und Wolfsegger Granit bis zu den sauren Graniten vom Typus Schrems und Mauthausen und deren Ganggefolge. Daraus läßt sich ableiten, daß speziell die Diorite ein Produkt einer magmatischen Differentiation darstellen und gewissermaßen als basische Vorläufer der jüngeren Granite aufzufassen sind. Aufgrund von Tracht, Habitus und Wachstumstendenz der akzessorischen Zirkone ist allerdings eine direkte genetische Verwandtschaft zwischen den Dioriten (und dem Gabbro von Kleinzwettl) einerseits und den Graniten vom Typus Mauthausen, Schrems und Wolfsegg nicht anzunehmen. Tracht, Habitus und Einschlußtypen der Zirkone der basischen Gesteine schließen dagegen eine genetische Bindung zur Masse des Weinsberger Granites nicht aus. Trotz der sehr deutlichen geochemischen Entwicklungstendenz der untersuchten Massengesteine ist daher eine gewisse Eigenständigkeit der Magmenentwicklung der Diorite und deren gabbroider Vorläufer anzunehmen.

Notes: Summary The structure of hydrothermally synthesized cliffordite, approximate formula UTe3O9, space groupPa3-T h 6 ,a=11.335(5) Å was refined toR=0.053 with 501 independent three-dimensional diffractometer data. A full matrix least squares refinement yielded for one of the two U-positions a site occupancy factor of 0.82. A quantitative electronprobe microanalysis confirmed the corresponding U:Te ratio. A discussion of the charge balance is given. From reflectivity measurements the refractive indexn of cliffordite was determined to be 2.25(2) for λ=5890 Å.

Notes: Zusammenfassung Die Kristallstruktur des Minerals Teschemacherit, NH4CO2(OH), (a=7,255,b=10,709,c=8,746 Å;Z=8, Raumgruppe:Pccn) wurde an synthetischem Material mit 3-dimensionalen Röntgendaten verfeinert. Die Struktur wird aus parallel [001] verlaufenden [CO2(OH)]−-Ketten aufgebaut. Wasserstoffbrücken zu [NH4]+-Gruppen verbinden diese Ketten zu einem 3-dimensionalen Gerüst.

Notes: Summary The Habachtal emerald deposit, Hohe Tauern, is composed of blackwall sequences of the type: serpentinite — talc schist — ±chlorite schist or actinolite schist — biotite schist —albite gneiss and/or micaschist. 2 serpentinites, 33 blackwall rocks, 9 micaschists, 10 albite gneisses, and 5 aplitic gneisses were analyzed for major elements, and for Li, Be, Cr, Ni, Zn, Zr, Sn, in 36 samples also for Sc, Cu, Rb, Sr, Cs, Ba, W. The blackwall formation is due to a metasomatic exchange involving a transfer of Mg from the serpentinite to the silicic country rock, and of Si, Ca, K, and Al from the country rock to the serpentinite. Some of the trace elements were also mobile: Compared to serpentinite, Li and Be were enriched in all the blackwall rocks, and Sn and Cs in the actinolite, chlorite, and biotite schists; Sr was concentrated in the dolomite-bearing talc schists, and Zn, Rb, and Ba predominantly in the biotite schists.

Notes: Zusammenfassung Die chemische Analyse des neuenMMinerals Lammerit mit der Elektronenmikrosonde ergab: CuO 49,9, ZnO 0,8, MgO 0,2, FeO 0,2 und As2O5 49,8, Summe 100,9%. Aus diesem Ergebnis wurde die idealisierte Formel Cu3[AsO4]2 abgeleitet. Lammerit kristallisiert monoklin. Die möglichen Raumgruppen sindP21 oderP21/m. Die Gitterkonstanten sind:a=5,080(2),b=11,616(6),c=5,391(2) Å, β=111,71(3)°,Z=2. Die stärksten Linien des Pulverdiagramms sind: 4,06(5) ( $$11\bar 1$$ ), 3,80(6) (021), 3,06(8) (031), 3,00(8) (130), 2,89(10) (040, $$13\bar 1$$ ), 2,84(7) (111), 2,62(8) (121), 2.59(8) ( $$11\bar 2$$ ), 2,52(9) ( $$20\bar 1$$ , 041), 2,09(5) (150) und 1,582(6) ( $$25\bar 2$$ , 241). Lammerit ist dunkelgrün durchscheinend. Die Kristalle sind tafelig nach {100} und zu radialstrahligen Aggregaten verwachsen. Die Spaltbarkeit nach {010} ist ausgezeichnet, nach {100} gut und nach {001} angedeutet. Das Mineral ist optisch zweiachsig positiv, 2V∼54±5°. Die Werte der Lichtbrechung sind:n α≲1,89,n β=1,90 undn γ=1,95. Lammerit ist stark pleochroitisch mit den AchsenfarbenX=hellblau,Y=himmelblau undZ=bläulichgrün. Die Auslöschung istn α‖b und auf (010)n γ⋏c∼40°.H (Mohs)∼3,5–4.D=5,18 undD X =5,26 g·cm−3. Lammerit kommt gemeinsam mit Olivenit und einem weiteren vermutlich neuen Mineral vor. Der Fundort war Veta Negra. Laurani, Bolivien.

Notes: Summary A detailed electron microprobe study of the mineralogy of fifteen eclogites from the Moses Rock kimberlitic dyke, Utah, has demonstrated complexity in compositional zoning of minerals. Most of the eclogites examined are of the almandine-jadeite type and zonal and irregular variation in grossular content of garnet and acmite, jadeite and diopside-hedenbergite content of pyroxene produce large uncertainties in temperature estimates based on Fe/Mg partitioning between garnet and clinopyroxene. Zoning pattems of increasingX Mg in both clinopyroxene and garnet, and increasingX Jd in clinopyroxene, suggest the introduction of Mg and Na throughout the evolution of these essentially bimineralic assemblages. Averaged data yield temperatures from 340°C to 500°C at 10 kbar for compositions of rims of coexisting garnet and clinopyroxene. Two samples contain pyrope-rich gamets but coexisting pyroxenes are extremely magnesian and temperatures of equilibration of both primary omphacite-pyrope and secondary omphacite-almandine/pyrope-chlorite are only slightly higher (500–650° at 10 kbar) than those for almandine jadeite eclogites and estimates overlap with those of some examples of the latter type. Unlike the majority of almandine-jadeite eclogites, two examples contain garnets with almandine-cores and pyrope-rich rims without accompanying variation in grossular content. The simple interpretation of these samples as evidence of garnet growth during prograde metamorphism is precluded by complex zoning in coexisting clinopyroxene. The eclogites provide evidence for the presence of a metamorphic terrane including rocktypes resembling those of blueschist terranes beneath the Colorado Plateau but do not permit deduction of theP,T path by which such rocktypes reached theirP,TT-conditions (∼10 kbar, 400–600°C) of metamorphism.

Notes: Summary A meta-ironstone, composed essentially of eulite, almandine and quartz, and locally containing ferrifayalite (Fe4−x (SiO4)2), magnetite, clinopyroxene, biotite, graphite and plagioclase, was discovered at Louzi Mountain, Qianan, Eastern Hebei province, China. Its parent in terms of bulk rock chemistry is probably a Fe-rich sediment. The mineral chemistry and the distribution coefficient of Fe2+ and Mg between coexisting ferromagnesian minerals are defined, and also the inferared and Mössbauer spectra. According to the two-pyroxene geothermometers ofWood andBanno (1973),Saxena (1976), andWells (1977), the equilibrium crystallization temperature of the rock was about 750°C, and the pressure according toWood's method (1974) is about 13 kb at that temperature. It is implied that the rock has undergone granulite facies metamorphism.

Notes: Abstract After a discussion of the observed phenomena a short account of the very-long-baseline radio interferometry and the redshift controversy is given. The issue of superluminal velocities in the theory of relativity is clarified and a variety of physical models that have been proposed to account for the observed phenomena are discussed. Finally the data of some superluminal sources and their implications are reviewed.

Notes: Abstract Progress in understanding of interferon-mediated mechanisms over the past 20 years has been steady although slow. A major obstacle has always been the difficulty of obtaining sufficient quantities of highly purified interferera. Rational therapeutic applications therefore depend on a solution of problems connected with mass production and purification of interferon.

Notes: Abstract During shock the organism reacts by means of primarily useful autoregulation mechanisms which, however, in excess become useless and at least harmful. Therapeutically it is necessary now, to partly break through these mechanisms going along with substitution of certain necessary substances and besides that in part to support the organism's own concept.

Notes: Abstract There are 109±0.5 neutron stars in the Galaxy. They are born in supernova explosions. Isolated neutron stars are observed as (radio-)pulsars, in some cases also as γ-ray pulsars and as IR-, optical and X-ray pulsars. Binary neutron stars, when accreting mass from their companion, become flickering, periodic and/or bursting X-ray sources, and probably also γ-ray bursters. They may all derive from binary star systems. The masses of population-I-neutron stars are compatible with (1.4 ±0.2)M ⊙; their surface magnetic fields fall almost exclusively within 1012.2 and 1013.2 Gauss (at birth). The radii of population-II-neutron stars are (10 -3 +6 )km. Even in exotic sources like SS 433 and Cyg X-1, the compact core may well be a neutron star.

Notes: Abstract Synthetic hydrophilic polymers find promising applications in pharmacology, biotechnology and chemistry. The biocompatibility, biodegradability and pharmacological activity of these polymers depend much on their hydrophilic nature. This article summarizes the recent developments in the utilization of the different classes of these hydrophilic polymers as pharmacologically active agents, for enzyme modification and as catalysts and supports for chemical reactions.

Notes: Abstract Plankton algae occasionally produce water blooms in which cell density may be so high as to colour the water reddish or yellow-brown. Some of these organisms exhibit considerable toxicity. While the marine toxic species belong almost exclusively to the dinoflagellates, toxin producers of limnic habitats are mostly blue-green algae. Some chemical and pharmacological properties of algal toxins are discussed.

Notes: Abstract The 100th anniversary of Beilstein's Handbook of Organic Chemistry, founded in 1881, merits a brief description of the principal concepts and goals of the literary genre “scientific handbook” in general. Systematic arrangement, critical data and fact evaluation, thoroughness and reliability are among these goals, thus providing the handbook user with a concise compilation of carefully checked and cross-referenced information in his particular field of interest.

Notes: Abstract Interactions of organic materials with solid surfaces can be successfully studied with inorganic layer crystals that take up organic compounds between the layers. The kind of information obtainable is illustrated by three selected examples. Investigations with long-chain compounds clarify the possible chain conformations in planar alkyl chain aggregates (mono- and bimolecular films). Studies with polyelectrolytes demonstrate the influence of the charge patterns on polymer adsorption and interactions with nucleotides present very specific adsorption phenomena.

Notes: Abstract We use hydra as a model system to understand how growth and differentiation and, as a consequence of this, pattern formation are controlled at the molecular level. We have found that four substances control head and foot formation in hydra: an activator and an inhibitor of head formation and an activator and an inhibitor of foot formation. The two activators are peptides with molecular weights around 1000 daltons, the inhibitors are smaller in molecular weight (〈500), have an overall positive charge and do not contain peptide bonds. In normal animals all four substances are present and most likely produced by nerve cells. We hope to understand how these substances act and interact to create the spatial and temporal pattern of growth and differentiation typical for hydra.

Notes: Abstract Investigating quarks, leptons or even smaller particles reveals that the description of matter by ultimate constituents with interacting forces loses in significance in favor of the concept of fields. Essential progress concerning the understanding of the various forces and important steps towards their unification give hope for a unique, even if abstract description of nature, which might also bring the old question closer to a solution why laws of nature exist at all.

Notes: Abstract In each generation cycle of a higher organism, a complex structure is formed under the instruction of the genes. In this process morphogenetic fields (probably spatial concentration patterns of substances) are involved which elicit cell responses giving rise to visible pattern and form. Autocatalytic short-range activation in conjunction with long-range (“lateral”) inhibition is capable of generating striking concentration patterns starting from near-uniform distributions. No features unusual in molecular biology are required, and self-regulatory properties observed experimentally in biological development can be accounted for. Cell responses to morphogenetic fields can include cell differentiation and the generation of bending moments, curvature and form in cell sheets giving rise to defined forms in organs and organisms. It appears that biological pattern formation is explicable on the basis of known physical laws and processes.