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The ozone layer is regarded as an invisible filter that protects all life from the dangerous overexposure to ultraviolet rays. The thinning of the ozone layer over the South Pole stratosphere of our planet is a seasonal phenomenon that takes place every year during the spring since the 80s and is known as the “ozone hole”. It is developed on the Antarctic, reaching an area of 30 million square kilometers approximately. In the spring begins to deform reached lower latitudes, presenting specific cases of low total ozone column over Rio Gallegos (51 ° 36 'S, 69 º 19' W) due to the passage of the hole and its border over this city, which can derive in UV indices greater increasing the UV radiation impact on surface. This study evaluates the statistical dependence of the UV index with total ozone column and cloud optical thickness in the Patagonian city of Rio Gallegos for spring and summer. Another aim is to quantify the attenuation of UV radiation produced for the clouds to cases that the ozone hole is passing over the city. The cloud optical thickness and UV index data analyzed were obtained at Station CEILAP RG (CITEFA-CONICET) with a narrowband multichannel radiometer GUV-541 (Biospherical Inc.), and the total ozone column data were extracted from the Satellite OMI / AURA database of NASA. All these belong to the spring and summer seasons of the October 2005-December 2008 period. It is noted that 25% of ozone hole cases in springtime, which would result in a high UVI on Rio Gallegos, are strongly attenuated by the clouds.

The stratospheric ozone (O3) is one of the most important gases in our atmosphere due to its capacity to absorb biologically harmful solar radiation (called UV-B) that would otherwise arrive to the terrestrial surface producing dangerous effects on different organisms. On the other hand, the nitrogen dioxide (NO2) is a key trace gas in the ozone photochemical. The systematic sensing of the concentration of NO2 and other minority gases is essential in order to understand the stratospheric ozone destruction and formation processes. In this work we present the study carried out on the seasonal variation of the atmospheric O3 and NO2 vertical column concentration, using a SAOZ spectrometer (System d' Analyse par Observation Zenitale) belonging to the Service d'Aéronomie (Centre National de Recherche Scientifique, France), located in Río Gallegos, Santa Cruz province (51º 36’ S, 69º 19’ W), in the CEILAP-RG remote sensing station. We analyze the correlation between the O3 and NO2 concentration and study the behavior of these gases in ozone hole situation. Likewise, we compare the ground-based measurement with those coming from the OMI/AURA (Ozone Monitoring Instrument, AURA satellite)

For the retrieval of the vertical distribution of ozone in the atmosphere the Ozone ProfilE Retrieval Algorithm (OPERA) has been further developed. The new version (1.26) of OPERA is capable of retrieving ozone profiles from UV-VIS observations of most nadir looking satellite instruments like GOME, SCIAMACHY, OMI and GOME-2. The set-up of OPERA is described and results are presented for GOME and GOME-2 observations. The retrieved ozone profiles are globally compared to ozone sondes for the year 1997 and 2008. Relative differences between GOME/GOME-2 and ozone sondes are within the limits as specified by the user requirements from the Climate Change Initiative (CCI) program of ESA. To demonstrate the performance of the algorithm under extreme circumstances the 2009 Antarctic ozone hole season was investigated in more detail using GOME-2 ozone profiles and lidar data, which showed an unusual persistence of the vortex over the Río Gallegos observing station (51° S, 69.3° W). By applying OPERA to multiple instruments a timeseries of ozone profiles from 1996 to 2013 from a single robust algorithm can be created.

[1] This paper presents an analysis of satellite and ground-based measurements of total O3 columns and the UV index of a unique event during the 2009 Antarctic O3 hole season. From 11 to 30 November 2009 the Antarctic vortex was located just south of the southern tip of South America rather than at its climatological position over Antarctica. Analysis of 30 years of assimilated total O3 column and UV index measurements shows that this 20-day event was unique in the history of the ozone hole for these latitudes. During this period, small total O3 columns and large UV index values were observed over the southern tip of South America. Comparison of ground-based and satellite measurements of total O3 columns and satellite based calculations of the UVI index – never designed nor validated for such extreme Southern Hemisphere conditions – show excellent agreement.

Es wurden Flussigkeitsbrucken aus wasrigen Natriumdodecylsulfatlosungen verschiedener Konzentration zwischen Polytetrafluorathylen und Glasoberflachen in n-Octan untersucht. Die Verteilungsisothermen sind vom gleichen Typ unabhangig von der Tensidkonzentration, die charakteristischen Werte der Umhaftungskurven, wie die kritische Tropfenmasse, bei der noch vollstandige Umhaftung erfolgt und die dem stationaren Zustand entsprechende konstante Umhaftmasse, aber stark von der Tensidkonzentration abhangig. Die Stabilitat der Brucke sowie die Bildung von Satellittropfchen nach Aufspalten wird anhand von Kapillarwellen interpretiert. Zur Erklarung von Hystereseeffekten wird eine einfache energetische Modellbetrachtung angewandt.

Aus wasrigen Polyvinylalkohollosungen durch chemisches Vernetzen mit Glutaraldehyd entstehen Gele, die infolge molekularer Inhomogenitaten eine quasidisperse Struktur aufweisen. Diese Struktur wird betrachtlich beeinflust durch Polyvinylpyrrolidon. Der Effekt hangt stark vom Molekulargewicht und der Konzentration beider Polymere ab, und es konnen sowohl Bereiche mit hoher Segmentdichte, als auch Mikrotropfchen entstehen. Diese Schlusfolgerung wurde an Hand von optischen, mechanischen und Quellungsmessungen gezogen.

The displacement of n-dodecane by aqueous solutions of sodium dodecyl sulfate in glass capillaries with periodically varying cross-section has been studied. By measuring the dynamic contact angles of the moving fluid interface upon variation of surfactant concentration c s , flow rate v and viscosity ratio {ie82-1}, of oil to water according to a three-level quadratic experimental design, significant pair-interdependences have been found between the influence of c s and v as well as between that of c s and {ie82-2} on the displacement. The results indicate that in addition to these parameters which are generally used to characterize the efficacy of oil displacement, other factors such as surface viscosity and rigidity of the liquid/liquid interfacial film as well as the stability of the oil film adhered to the capillary wall have to be taken into account, too.

Liquid flow as disturbed by the presence of a fluid interface of definite shape was studied during immiscible liquid/fluid displacement in a capillary tube. Microscopic cinematography with tracer method has been used to obtain flow patterns on both sides of the moving interface. The effect of the curvature of the interface on the distribution of velocity components was investigated. The experimental results obtained for flat liquid/fluid interfaces were compared with those calculated from an approximate solution of the flow equation by Kafka and Dussan V.

The temperature dependence of equilibrium concentration of swollen polyvinyl acetate gels was studied below and above the ϑ temperature. Collapse was not observed. An analysis of the classical gel theories as well as the experimental results has shown that the James-Guth theory is adequate to describe the experimentally found universal dependence of φ θ /φ on τ/φ θ (where φ is the equilibrium concentration of the gel, τ is the reduced temperature and the ϑ subscript refers the ϑ state). It was also found that upon cooling below the ϑ point a continuous non-phase transition occurs.

The kinetic and thermodynamic properties of aldolase and D-glyceraldehyde-3-phosphate dehydrogenase were studied in the presence of soluble poly(vinyl alcohol), poly(N-vinyl pyrrolidone) and poly(acrylic acid). Two kinds of aldolase preparations were found which did not differ in specific activity, but showed differences in respect of their kinetic response to polymer action. Preparation type a was more active at low concentrations of the polymers, and less active at high concentrations, than in buffer solution. In the case of type b preparation the polymer concentration dependence was detectable only in solutions containing poly(acrylic acid); poly (vinyl alcohol) had no effect in the concentration range studied, whereas poly(N-vinyl pyrrolidone) caused inhibition rather than activation of the enzyme. However, the thermodynamic data indicate that the polymer interacts with the enzyme even in those cases where kinetic effects are absent. Alteration of the steric structure of poly(vinyl alcohol) by intramolecular crosslinks caused qualitative changes in its effect on aldolase activity. In the case of D-glyceraldehyde-3-phosphate dehydrogenase, a dissociable tetramer, the kinetic consequences of polymer action depend on the oligomeric state of the enzyme. It appears that the above non-specific enzyme—macromolecule interactions are considerably influenced by the colloidal state of both interacting partners.

A quantitative model based on the hydrophobic interaction concept has been presented for the polymer—surfactant complex formation and checked by potentiometric measurements using Au/Hg/Hg l DS and sodium-ion selective glass electrodes. The interaction of sodium dodecyl sulfate (NaDS) with poly-(vinyl alcohol) (PVA). poly-(vinylpyrrolidone) (PVP) and poly-(ethylene oxide) (PEO) has been investigated. The polymer surfactant complex formation is characterized by the cooperativity of the process, i.e., by the formation of surfactant aggregates (subunits), which are smaller than the ordinary micelles, being distributed along the polymer chain. The aggregation number of subunits for the PVA-NaDs complex is 12 and it increased with the counter-ion concentration. In the presence of 0.1 M excess NaNO 3 the aggregation numbers are between 40 and 50 for all the polymer—NaDS complexes concerned here. The standard free energy change of the transfer of DS-ions into surfactant complex subunits are very close to that of the micelle formation, which confirms that the main driving force of the polymer—surfactant complex formation is the micelle-like aggregation of the surfactant ions. The energy contribution arising from the interaction between the subaggregates being in the same polymer chain seems to be insignificant comparing to that of the sub-aggregate formation. The binding of the surfactants to the polymer (or the increase of the complex concentration) with increasing amount of surfactants is interrupted by the free micelle formation, because the surfactant monomer activity reaches its upper limit. In the case of the PVA—NaDS system the degree of binding is far from saturation but, at the beginning of the micelle formation, the PVP—NaDS and PEO—NaDS system approach it. The presenteoi treatment explains adequately the shape of binding isotherms of ionic surfactants by polymers, e.g. as observed by equilibrium dialysis and surface tension measurements.

Es wurden Stromungspotentiale in den Systemen Bariumsulfat/wasrige Natriumalkylsulfatlosungen (Gruppe A) sowie Cellulosefaserstoffe/wasrige Aluminiumchloridlosungen (Gruppe B) gemessen und Zetapotentiale, unter Anwendung einer Korrektur fur die Porenleitfahigkeit (χP), berechnet. Das Verhaltnis χP/χV (χV — normale Leitfahigkeit) lauft in Abhangigkeit von der Konzentration der Losung bei Gruppe A durch ein Minimum, wogegen es bei Gruppe B monoton abnimmt. Dieser Befund wird auf qualitative Weise gedeutet. Streaming potentials of the systems barium sulfate/aqueous solutions of sodium alkyl sulfates (group A) as well as cellulose fibres/aqueous solutions of aluminium chloride (group B) have been measured, and zeta-potentials were calculated using a correction accounting for the pore conductivity (χP). The ratio χP/χV (χV — ordinary conductivity) varies in dependence of the solute concentration according to a minimum curve for group A, but decreases monotonically for group B. This finding is interpreted in qualitative terms.

The kinetic properties of rabbit muscle aldolase have been studied in solutions containing various amounts of poly( N -vinyl pyrrolidone) or poly(vinyl alcohol) of different molecular weights. At low polymer concentrations both polymers enhance the maximum rate of cleavage of fructuose 1,6-bisphosphate, whereas at high concentrations inhibition occurs. In the presence of polymers of low molecular weight excess substrate inhibits the enzyme reaction, a phenomenon not observed in the absence of polymers. The thermal denaturation of the enzyme is markedly increased by the presence of polymers. It is suggested that the principal effect of these polymers is most probable the alteration of the enzyme conformation.

The applicability of the drop weight method for determining time dependent surface tension of surfactant solutions was experimentally proved.

Es wurde die Benetzbarkeit von Polymeroberflachen verschiedener Polaritat durch wasrige Losungen ionogener Tenside untersucht. Es wurde der vorruckende Randwinkel von Losungstropfen sowie die Oberflachenspannung der Losungen gemessen. Die fruher vonBernett undZisman und auch vom Verfasser fur die Spreitung vonreinen Flussigkeiten gefundene Linearitat zwischen dem Cosinuswert des Randwinkels und der Oberflachenspannung konnte im allgemeinen nicht bestatigt werden. Dagegen trifft im Falle von unpolaren Oberflachen wie Polytetrafluorathylen und Paraffin die vom Verfasser fruher festgestellte Linearitat zwischen Benetzungs- und Oberflachenspannung zu. Bei nicht vollkommen unpolaren Oberflachen treten jedoch in den cosΘ,γ L -Kurven Wendepunkte, Knickpunkte, ja sogar Minima bei Oberflachenspannungswerten auf, die mitunter weit oberhalb von derγCMC liegen (das ist die der CMC entsprechende Oberflachenspannung). Im Falle von relativ stark polaren Polymeren (z. B. Polyathylenterephthalat, Polycarbonat) tritt auch unterhalb von derγ c (der kritischen Oberflachenspannung nachZisman) keine Spreitung auf. Die der CMC entsprechenden Randwinkel sind — bis auf wenige Ausnahmen — unabhangig von der Art des Tensids und des Polymers.

1. Es wird die Peptisationsgeschwindigkeit von Fe(OH)3-, Al(OH)3-, Cr(OH)3- und Berlinerblau-Gelen bei verschiedenen Temperaturen (0°, 15°, 25°, 35° und 50° C) gemessen. Als Peptisatoren wurden HCl-, FeCl3-, AlCl3-, NaOH- und K2C2O4-Losungen angewandt. 2. In Ubereinstimmung mit fruheren Untersuchungen wird gezeigt, das die Peptisation in der Zeit im allgemeinen entsprechend einer S-formigen Kurve verlauft und quantitativ durch die Gleichung $$ - \frac{{d(x_\infty - x)}}{{dt}} = (k + k'x)\,(x_\infty - x)$$ dargestellt werden kann. 3. Die Peptisationsgeschwindigkeit nimmt sowohl mit der Zunahme der Peptisatorkonzentration, wie mit der Temperatur zu. Zugleich verschiebt sich der Wendepunkt nach kleinerent-Werten, um schlieslich vollkommen zu verschwinden. Im letzteren Falle vereinfacht sich die obere Gleichung zu der der monomolekularen Reaktionen: $$ - \frac{{d(x_\infty - x)}}{{dt}} = k(x_\infty - x)$$ . 4. Es wird gezeigt, das fur die Temperaturabhangigkeit derk-Konstante die Arrheniussche Glei chung gultig ist. Es wird auf Grund dieses Zusammenhanges die Aktivierungswarme der Peptisation ausgerechnet. Die Grosenordnung der Aktivierungswarme ist 10 kcal pro Mol. 5. Es wird auf die charakteristischen Unterschiede zwischen den hydrophoben und hydrophilen Gelen bezuglich der Kinetik der Peptisation hingewiesen.

Comparison of the spectra of syndiotactic, isotactic and atactic polypropylene illustrates the sensitivity of the infrared spectrum to changes in polymer systems resulting from stereoregularity. The bands are classified according to general types dependent on stereoisomer, degree of coupling due to stereosequence length, and the helical conformation.

Die Darstellung der Seleninsaureanhydride (RSeO)2O mit R = CH3, CF3, C2H5 und C6H5 gelingt sowohl durch Oxydation der entsprechenden Diselenide RSeSeR mit O3 als auch mit NO2. Es werden einige Eigenschaften mitgeteilt und die Schwingungsspektren diskutiert. Aus dem Solvolyseverhalten und den Schwingungsspektren folgt im Gegensatz zu den analogen Schwefelverbindungen, die SS-Bindungen enthalten, echte Anhydridstruktur mit gewinkelter SeOSe-Brucke. The seleninic acid anhydrides (RSeO)2O with R = CH3, CF3, C2H5 and C6H5 have been prepared by oxidation of the diselenides RSeSeR by means of O3 as well as NO2. Some properties and the vibration spectra are given and discussed. Contrary to the analogous sulphur compounds which contain SS bonds, bent SeOSe bridging groups are deduced from the solvolytic behaviour and the vibration spectra.

Die Seleninsaurechloride RSeOCl mit R = CH3 und C2H5 lassen sich sowohl durch Umsetzung von RSeCl-Losungen mit O3 als auch mit NO2 darstellen. Dagegen erhalt man aus CF3SeCl nur mit O3 das CF3SeOCl, wahrend mit dem NO2 Weiterreaktion von primar gebildetem CF3SeOCl zum (CF3SeO)2O und NO2Cl erfolgt. Es werden einige Eigenschaften der Verbindungen mitgeteilt. Es ergeben sich zwischen dem CF3SeOCl einerseits und den Alkylverbindungen andererseits merkliche Unterschiede im Schmelzpunkt, in der Fluchtigkeit, im Loslichkeitsverhalten, in der Stabilitat und der Reaktivitat, die auf Polaritatsunterschiede der Bindungen zuruckgefuhrt werden. Das CF3SeOCl hydrolysiert zur Saure CF3SeOOH, die Chloride CH3SeOCl und C2H5SeOCl dagegen zu den Salzen [RSe(OH)2]Cl. Die Umsetzung von RSeOCl (R = CH3, C2H5) mit NaOCH3 in CH3OH ergibt die Ester RSeOOCH3. Die partielle Hydrolyse von C6H5SeCl3 in Gegenwart von Pyridin fuhrt zum Komplexsalz [PyH][C6H5SeOCl2]. The seleninic acid chlorides RSeOCl with R = CH3, C2H5 are prepared by reaction of RSeCl solutions with O3 as well as with NO2. On the other side, CF3SeOCl can be prepared only by reaction of CF3SeCl with O3 whereas with NO2 the primarily formed CF3SeOCl reacts in a second step to (CF3SeO)2O and NO2Cl. Some properties of the seleninic acid chlorides are studied. There are remarkable differences between CF3SeOCl and the alkyl compounds in melting point, volatibility, solubility, stability, and reactivity, which are caused by different bond polarities. Hydrolysis of CF3SeOCl yields the acid CF3SeOOH, whereas CH3SeOCl and C2H5SeOCl are transformed into the salts [RSe(OH)2]Cl. The reaction of the chlorides RSeOCl (R = CH3, C2H5) with NaOCH3 in CH3OH yields the esters RSeOOCH3. The complex compound [PyH][C6H5SeOCl2] is formed by partiell hydrolysis of C6H5SeCl3 in the presence of pyridine.

The development and design of the first continuously tuned production UHF converter to employ a silicon transistor oscillator is described. Discussed are the factors which contribute to a six to one reduction in volume, a 500 uv/m maximum radiation level, and lowered cost. The circuit is briefly described and performance curves are presented.

Die Grenzviskositat von Polyvinylalkohol (PVA) gelost in Mischungen von Wasser undn-Propanol andert sich nach einer Maximumkurve mit der Propanolkonzentration. Aus diesen Ergebnissen, sowie aus Messungen in Θ-Mischungen von Wasser und Propanol bzw. anderen niedermolekularen Alkoholen wurde unter Anwendung derFloryschen und derKurata-Stockmayerschen Theorie auf die Konformation und Solvatation des PVA-Molekuls geschlossen. Die fur die ungestorte statistische Kettenlange charakteristische, sich aus der Theorie ergebendeKθ-Konstante, die an sich unabhangig vom Losungsmittel sein muste, hangt von der Art des Alkohols, mit dem die θ-Zusammensetzung hergestellt worden war, ab. Sie ist in Athanol am grosten, was durch das Einbetten des quasi-erstarrten PVA-Molekuls in die stark assoziierte Struktur des Losungsmittelgemisches erklart werden kann. Die Zunahme der Grenzviskositat in Wasser-Propanol-Mischungen ist auf die bevorzugte Solvatation des PVA durch Wasser zuruckzufuhren.

Infrared dichroic measurements, refined to apply to Systems of low orientation, have been used to determine the structure of uniplanar and biaxially drawn polyacrylonitrile films. Orientation results in an alignment of the molecular chains with some degree of unkinking of the molecule. Preferential orientation of the nitrile side groups occurs due to the intermolecular dipolar attractions. Contrary to previous work, the results indicate that this dipolar interaction yields nitrile groups less well oriented than the chains with respect to the direction of draw.

Infrared spectroscopic methods have previously been developed for measuring the amount of structure and degree of orientation in three dimensions in polymer films. These methods involved tilting the sample with respect to the radiation beam. For samples with little orientation the results were found to be extremely sensitive to the accuracy of the absorbance measurements made at the tilted angle. This tilted absorbance measurement was required to determine the refractive index and path length of the refracted beam in the sample. The error in this sensitive measurement was reduced by utilizing a refractive index obtained from a multiple of measurements. The precision of the measurements was improved by 50% by this change in the method and suggests a simplification of the procedure. The improved method was utilized to study uniaxially drawn polyacrylonitrile films. It was concluded that only partial uniaxial orientation of the film was obtained.

It has been found that direct measurement of selective sorption of solvent mixture on the loosely crosslinked gels with low polymer concentration would yield some information on the preferential solvation and also on the nature of the interactions. Experimental data obtained by refractometry and sorption measurements carried out with the system poly(vinyl alcohol)-water-n-propanol have shown the proposed way of approximation to be successful. Based on the experimental results a solvate model for this system was proposed in which the n-propanol is bound to the polymer chain by both hydrogen and hydrophobic bonds.

Es wird an Hand von Messungen des Randwinkels an horizontalen, geneigten und vertikalen Oberflachen, sowie des Abrollwinkels und des kritischen Gewichts von Tropfen verschiedener Grose organischer Flussigkeiten an verschiedenen Polymeroberflachen und an Paraffin gezeigt, das Benetzen und Haften nicht unbedingt symbate Erscheinungen sind. Wahrend fur das Netzvermogen dieYoungDupresche („statische“) AdhasionsarbeitWSL=γL (1 + cosΘ) charakteristisch ist (γL: Oberflachenspannung der Flussigkeit,Θ: Gleichgewichtsrandwinkel), kann fur die Haftfahigkeit die „dynamische“ Adhasionsarbeit\(\Delta W_{SL} = \gamma _L (\cos \overleftarrow \Theta - \cos \overrightarrow \Theta )\) als Mas angesehen werden (\(\overrightarrow \Theta \): Vorruckwinkel,\(\overleftarrow \Theta \): Ruckzugswinkel). ΔWSL ist, bis auf einen Proportionalitatsfaktor, gleich der Abrollkonstanteka =m·g· sinx/2r π (α: Abrollwinkel,m: Tropfenmasse,r: Radius des Haftkreises).

In order to simulate microscopic processes that may occur during tertiary oil recovery, capillary tubes of glass, polyethylene and polyurethane withperiodically varying cross-section were prepared, and the displacement of highern-alkanes by aqueous solutions of sodium-dodecylsulfate was studied by means of microphotography. Investigated was the influence of the surfactant concentration, the flow velocity and the viscosity ratio of the two fluids on the dynamic contact angle and the distribution of the “oil” in the pores. It was found that both the extent of the hydrodynamically trapped oil and the way it occurs depends on the local geometry.

A simple rapid method has been developed for the quantitative analysis of styrene monomer in butadiene/styrene latexes using Raman spectroscopy. The latex samples were sealed in capillary tubes and scanned under high resolution conditions using a Spex Ramalog 1401 with a Spectra Physics 2 W argon ion laser. The Raman method involves ratioing the olefinic C=C (1632 cm−1) band of styrene monomer to the trans 1:4 C=C (1668 cm−1) band of butadiene in the butadiene/styrene polymer. Typical samples were found to have as low an unreacted styrene concentration as 0.7 wt. %. Reproducibility between samples was found to be within 0.1%. The values of residual styrene obtained by the Raman technique agreed within 0.25% with those obtained by liquid chromatography.

We have studied the kinetic consequences of the interactions of non-charged soluble polymers with enzymes. As polymers, poly-(vinyl-alcohol) (PVA) and poly-(N-vinylpyrrolidone) (PVP) appeared to be most suitable because their molecular weight and structure could be varied over a wide range. The enzymes studied were D-glyceraldehyde-3-phosphate-dehydrogenase (GAPD) and aldolase.