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Viscometric, mechanical and electron microscope investigations were carried out on mixtures of polyacrylonitrile (PAN) with its copolymers containing methyl methacrylate (MMA) and vinyl sulphate (VS) units. It was found that the compatibility of the components in solutions is reduced when the number of MMA and VS units in the copolymers is increased, as was also found in the case of differences in the molecular weight of the PAN. The tensile strength of films prepared from a mixture of PAN and its copolymers, containing up to 20% of the latter, is reduced as the number of MMA and VS units rises, while the number of double bends (in the case of the AN-MMA copolymer) is increased. It is shown that if the copolymer content of the mixtures exceeds 20%, the molecular weight of the PAN is the factor that has the most influence on the mechanical properties of the films.

It was empirically established previously that the relation γ 2 /γ 1 in the basic equation of gas chromatography could be substituted in some cases by V mol 2 / V mol 1 . Difficulties in the calculation of γ 2 /γ 1 have been overcome, as the new equation involves only physicochemical parameters of the solutes. The relation r exp 1,2 / r calc 1,2 is used as a measure of the specificity of phases which is related to hydrogen bonding of structure, but not of that due to differences in V mol . These properties of the phase could be evaluated by means of suitable standard solutes. The specificity of some phases for n -paraffins, aromatic hydrocarbons and chlorinated hydrocarbons, and its application to some simple calculations are discussed.

Der Einflus des Kupferphthalocyanins (I) und des basischen Bleiphosphits (II) auf die Wechselwirkung bei der gemeinsamen Thermobehandlung von Polycaprolaktam (PCA) und Polyathylenglykolterephthalat (PAT) im Schmelzzustand wurde untersucht. Die Zugaben von I und II in Mengen von 0,05 Gew.-% zu der Mischung inhibieren die Austauschreaktionen zwischen den beiden Polymeren. Oberhalb eines bestimmten Grades des Austausches enthalt das hochschmelzende Blockpolyesteramid eine in 85proz. Ameisensaure losliche Fraktion. Dies wird durch die Thermogramme der Proben nach dreimaliger Extraktion mit 85proz. Ameisensaure bestatigt. Der einzige Schmelzpeak hierin, der sich auf das hochschmelzende Blockpolyesteramid bezieht, ist deutlich schmaler zu hoheren Temperaturen verschoben. Die Zugabe von 1 Gew.-% von II zum Gemisch beschleunigt die Austauschreaktion zwischen PCA und PAT, wodurch die Doppelwirkung von II zum Ausdruck kommt. There has been investigated the effect of copper phthalocyanine (I) and basic lead phosphite (II) on the exchange interaction in a joint thermal processing in a melt of polycaprolactamide (PCA) and polyethylenglycolterephthalate (PAT). Added in a quantity of 0,05 mass-% with regard to the mixture of I and II, they inhibit the exchange reactions between the two polymers. It was found that above a definite degree of exchange interaction, the high melting block polyesteramide contains a fraction which is soluble in 85% formic acid. This is confirmed by the thermograms of the samples after triple extraction with 85% formic acid. The only peak of melting therein, referring to the high melting block polyesteramide, is considerably narrowed and moved on to higher temperatures. The addition of 1 mass-% of II of the mixture accelerates the exchange interaction between PCA and PAT, in which is expressed the double action of II.

Study of how insects attack wood, the types of damage they do and how to identify insects from the decayed wood. Detailed analysis of insecticides, the manner in which they affect insects and how to determine which solution to use. The restoration of three iconostasis is presented.

The possibility of misinterpreting results of the determination of γ-glutamyl transpeptidase (GGTP) activity in serum due to the influence of sulfonamides on the colour reaction or the enzymic reaction itself was assayed. Five sulfonamide drugs were tested in vitro and in 46 patients. GGTP activity was estimated by four methods. The results of the naphthylamide method were influenced (in the sense of some increase of the values) by the sulfonamides with antibacterial effect, by way of interference of these sulfonamides with the Bratton and Marshall procedure used in this method. The values obtained with the naphthylamide-glycylglycine method were not influenced by any sulfonamides. By two methods, using γ- l -glutamyl -p- nitroanilide , it was found that at a therapeutic sulfonamide concentration in blood, no inhibition of serum GGTP activity was observed.

Empirical correction of the physico-chemical retention indices of hydrocarbons on squalane Peaks obtained by gas chromatography of an oil fraction of wide boiling range on squalane can be identified on the basis of corrected physico-chemical retention indices. A method is given for the calculation of the correction factors of these retention indices. The corrected physico-chemical retention indices and the retention indices after Kovats have been listed for 68 paraffinic, naphthenic and aromatic hydrocarbons.

(1)The minimum measured brightness of the night sky (in the visual region) is about 100 stars of the 10th magnitude per square degree near the galactic poles.(2)The ratio of fluxes in the ultraviolet (2300–3000 Å) and visual regions is approximately in agreement with expected theoretical data based on the models of stellar atmospheres for spectral classes B0 to G5 and on the distribution of stars of the different spectral classes over the sky.(3)The nature of possible deviations (theory minus observation) is discussed.

Die unter betrieblichen Bedingungen gewonnenen Produkte aus der Umesterung von Dimethylterephthalat (DMT) mit Athylenglykol (AG) in Anwesenheit zweier Katalysatoren (Calciumacetat und das Gemisch von Mangan- und Natriumacetat) wurden untersucht. Die bei unterschiedlicher Reaktionsdauer erhaltenen Produkte (Umesterungsprodukt und Destillat) wurden analysiert. Aus den Ergebnissen wurde der Einflus der Dauer und der Temperatur der Reaktion und der Katalysatorart auf den Verlauf von Haupt- und Nebenreaktionen festgestellt. Die Umesterung vollzieht sich uber einen Mischester der Terephthalsaure, namlich uber das Methylathylolterephthalat. Nach Umesterung der Methylestergruppen des Methylathylolterephthalats und des Dimethylterephthalats hort die Reaktion nicht auf, sondern geht mit einer Oligomerisation des Diathylolterephthalats weiter. Der Prozes endet mit Bildung von etwa 82% Oligomeren bei Calciumacetat als Katalysator und 93% bei dem Mischkatalysator. Die Versuchsergebnisse zeigen, das ein Teil der Ausgangsprodukte DMT und AG an nichterwunschten Nebenreaktionen teilnehmen: Hydrolyse des DMT bis zur Terephthalsaure, Zerfall des AG bis zum Acetaldehyd und Bildung von Diathylenglykol. Nach den erhaltenen Ergebnissen besitzt der Mischkatalysator die hohere Effektivitat. The products of the ester exchange of DMT with EG in the presence of two catalysts (calcium acetate and a mixture of manganese and sodium acetate) obtained under manufacturing conditions have been investigated. The ester exchange product and the distillate obtained during different reaction times were analysed. On the base of the obtained results of the effect of the duration and temperature the reaction was established as well as of the type of catalyst on the progress of the fundamental and by-reactions. It was found that the trans-esterification proceeds through a mixed ester of terephthalic acid, namely methylethylolterephthalate. After the trans-esterification of the methylester groups of methylethylolterephthalate and DMT the reaction does not stop, but continues with the oligomerization of the diethylterephthalate. At the end of the process about 82% of oligomers are obtained when the catalyst is calcium acetate and 93% with the mixed catalyst. The experimental results show that part of the initial monomers participate in undesired side-reactions (by-processes): hydrolysis of DMT to terephthalic acid and breaking down of EG to acetaldehyde. The results obtained indicate the greater effectiveness of the mixed catalyst.

A 1.5-Gev electron synchrotron is described. The synchrotron is of the weakfocusing type with a magnetic-field fall-off index of n= 0 58 The machine operates under pulse conditions, with a repetition frequency of 1 cps. The injector is a 5.5-MeV mierotron. A voltage of 240 kV is required to accelerate electrons to 1.5 GeV, and this is designed to be supplied by two resonators. An energy of 1.1 GeV and an acceleratedbeam intensity of 1.2·1010 particles per pulse was obtained in 1965 on a synchrotron with one resonator.

Products of pre-esterification of dimethyl terephthalate with ethylene glycol at various times carried out with two catalysts, i.e., calcium acetate and a mixture of manganese and sodium acetates, were studied. Thin-layer chromatography was used to follow the fundamental reaction and determine the type and degree of oligomerization. It was established that the manganese–sodium acetate mixed catalyst is more efficient both with regard to pre-esterification and oligomerization.

Resume Differentes interventions chirurgicales portant sur les nerfs faciaux et la musculature perioculaire ont ete realisees chez des Papio papio plus ou moins photosensibles. La resection du nerf facial fait apparaitre dans les mois qui suivent, un spasme facial predominant au niveau de la musculature peribuccale. La resection de la musculature perioculaire provoque, dans les semaines qui suivent l'intervention, des modifications des potentiels evoques visuels dans le territoire fronto-rolandique ou ils revetent un caractere paroxystique. L'etude de leur cycle d'excitabilite fait apparaitre une facilitation importante de leurs composantes tardives. Le degre de photosensibilite est peu modifie par ces deux types d'intervention, mais le declenchement des myoclonies chez des animaux anterieurement photosensibles a ete plus aise qu'auparavant. Les relations entre les decharges paroxystiques provoquees par la stimulation lumineuse intermittente a differentes frequences au niveau fronto-rolandique et les myoclonies faciales qui leur sont associees sont etudiees en detail. Les rapports entre spasme facial et photosensibilite d'une part, et resection de la musculature perioculaire et modifications des PEV fronto-rolandiques d'autre part, sont discutes ainsi que leur mode d'apparition.

According to the modern views, coronary heart disease (CHD) is a heterogeneous disease with pathophysiological and pathomorphological features. In clinical practice, CHD often is combined with other cardiac and extracardiac pathology, which results in certain clinical CHD types. The review describes the best-known of these types, as well as suggests the potential new types, which might affect early diagnostics and effective treatment of CHD.

A method has been elaborated for the dilatometric investigation of compressed samples of acetylcellulose (AC) with the aid of the derivatograph. The determined glazing temperature shows a good coincidence with the literatureTg data for fibres and films. This allows the conclusion that orientation processes do not affect the transition. The development of crystallization has been established predominantly in heterogeneous highly esterified AC (60% CH3COOH).

The present article provides the results of experiments on accumulating protons along a track with a constant magnetic field by means of the charge-exchange method under resonance conditions. The coherent effects connected with the high intensity were detected and investigated. It was established that the limitation of the orbital current is connected with the action of the longitudinal component of the beamTs electric field.

Auf zwei nach Zusammensetzung und Struktur unterschiedliche Zellstoffe - gebleichte Sulfit-und viskose Sulfatvorhydrolysecellulose - wurden Polyacrylnitrilseitenzweige aufgepfropft. Dabei wurde festgestellt, das mit Steigerung des Pfropfungsgrades bei Herabsetzung des mittleren Polymerisationsgrades der Pfropflinge und konstanter Polyacrylnitrilmenge das Acetyliervermogen fur beide Cellulosearten steigt und zwar besonders bei der Sulfitzellulose. Das Pfropfen erhoht den amorphen Anteil in den modifizierten Triacetylcellulosen, was mit einer Erhohung ihrer Loslichkeit in Dimethylformamid einhergeht. Es wurden viskosimetrische Prufungen uber die Strukturbildung in verdunnten Losungen von gepfropften Triacetylcellulosen in Dimethylformamid und in binaren Gemischen von Dimethylformamid/Wasser durchgefuhrt. Two celluloses, which were different in composition and structure (sulphite and sulphate cellulose), were grafted with side chains of polyacrylonitrile. It was found that with increase of the degree of grafting, and with decrease of the degree of polymerization of the side chains, under constant amount of grafted polyacrylonitrile the capacity of acetylation grows for both types of cellulose, especially for the sulphite cellulose. The grafting raises the amorphous part in the modified triacetyl celluloses being accompanied by an increase of their solubility in dimethyl formamide. Investigations on the structure formation in diluted solutions of grafted triacetyl celluloses in dimethyl formamide and in mixtures of dimethyl formamide and water were made by viscosimetric measurements.

The temperature coefficients of the physico-chemical index (PCI) of more than 75 isoparaffins, cycloparaffins and aromatic hydrocarbons have been calculated, tabulated and compared with the experimentally found Δ I /Δ T values. The discrepancy observed leads to errors of ±0.5 i.u. or less and rarely to ± i i.u. when the temperature of the analysis is changed over the range ± 20°.

A method is given for calculation of correction factors of the physicochemical indices (PCI) of mono- and dialkyl aromatic hydrocarbons. It was shown that the corrected PCI for the hydrocarbons are in agreement with the experimental retention indices I on squalane. Discrepancies observed are within the limits of the results obtained for the I, determined experimentally in different laboratories.