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The contemporary occurrence of juvenile gas emissions at springs or mofettes in active volcanic areas can be observed worldwide. This correlation is less frequent in areas with dormant or post-volcanic activity. The NW-Bohemia/Vogtland region located at the Eger rift zone (Czech Republic) provides an intriguing example of this correlation between numerous Neogene-aged post-volcanism locations and juvenile fluid emission sites. Newly discovered dikes and diatremes are located close to vents with the highest helium isotope ratios (3He/4He) of about 6 Ra. Our results lend support to the hypothesis that feeder dikes and their fractured wall rocks should be considered the predominant conduits for the continuous upwelling of juvenile fluids. Moreover, 77% of the CO2 gas emission sites are located close to dikes or diatremes, i.e., within a distance of 4 km. Our studies reveal a spatial dependence of the Ra values at the spring sites with the estimated distances to the basaltic bodies. The results confirm the negative trend known from the literature. That is, Ra values decrease with increasing distance from the feeder dikes.

Respiration rate (RR) is a proficient indicator to measure the health status of cattle. The common method of measurement is to count the number of respiratory cycles each minute based on flank movements. However, there is no consistent method of execution. In previous studies, various methods have been described, including counting flank movements for 15 s, 30 s or 60 s as well as stopping the time for 5 or 10 breaths. We assume that the accuracy of the aforementioned methods differs. Therefore, we compared their precision with an RR sensor, which was used as the reference method in this study. Five scientists from the fields of agricultural science and veterinary medicine quantified the flank movement according to each of the five methods mentioned above. The results showed that with an average RR of 30 breaths per minute (bpm), all methods showed a high correlation to the values of the RR sensor. However, counting breaths for 60 s had the highest level of conformity with the RR sensor (Lin`s concordance correlation coefficient: 0.96) regardless of the level of RR. With rising RR, the inaccuracy increased significantly for the other four investigated methods, especially when counting 5 and 10 breaths. Therefore, we would recommend that counting for 60 s should be used as the standard method for future studies due to its high precision regardless of the level of RR.

Respiration rate (RR) is a proficient indicator to measure the health status of cattle. The common method of measurement is to count the number of respiratory cycles each minute based on flank movements. However, there is no consistent method of execution. In previous studies, various methods have been described, including counting flank movements for 15 s, 30 s or 60 s as well as stopping the time for 5 or 10 breaths. We assume that the accuracy of the aforementioned methods differs. Therefore, we compared their precision with an RR sensor, which was used as the reference method in this study. Five scientists from the fields of agricultural science and veterinary medicine quantified the flank movement according to each of the five methods mentioned above. The results showed that with an average RR of 30 breaths per minute (bpm), all methods showed a high correlation to the values of the RR sensor. However, counting breaths for 60 s had the highest level of conformity with the RR sensor (Lin`s concordance correlation coefficient: 0.96) regardless of the level of RR. With rising RR, the inaccuracy increased significantly for the other four investigated methods, especially when counting 5 and 10 breaths. Therefore, we would recommend that counting for 60 s should be used as the standard method for future studies due to its high precision regardless of the level of RR.

The geodynamic activity of the NW-Bohemia / Vogtland region with its earthquake swarm activity is always studied in relation to the local emission of juvenile fluids, in particular of CO2. Based on a 3D interpretation of the geological setting, geophysical results, and new evaluation of existing data, our approach suggests a spatial separation of the upper crust into areas with differing pore fluids. The first area comprises a mixture of juvenile and meteoric pore fluids, where juvenile CO2 diffuses towards the surface. The second area exclusively contains meteoric and no juvenile pore fluids. It is in this area where the earthquake swarm activity occurs. This separation provides an important constraint which influences shear processes as the contrasting fluid chemistry induces different interaction of wall rock with pore fluids. Long-lasting chemical degradation of the wall-rock with clay as a typical alteration product in crustal volumes with pervasive CO2 discharge reduces the friction coefficients resulting in the weakening of the fault zone and allowing an aseismic slip according to the stress field. The presented studies suggest that the junction of two regional geological features of crustal scale, the N–S trending seismically active Leipzig-Regensburg-zone and the NW-SE trending fluid emission zone of magmatic volatiles, can be interpreted as a transition from frictional slip in the recent focal zones to aseismic behavior towards the southwest caused by clay coatings on the shear planes induced by a CO2 containing pore fluid.

The West Bohemia/Vogtland region is characterized by earthquake swarm activity and degassing of CO2 of mantle origin. A fast increase of CO2 flow rate was observed 4 days after a M L 3.5 earthquake in May 2014 in the Hartousov mofette, 9 km from the epicentres. During the subsequent 150 days the flow reached sixfold of the original level, and has been slowly decaying until present. Similar behavior was observed during and after the swarm in 2008 pointing to a fault-valve mechanism in long-term. Here, we present the results of simulation of gas flow in a two dimensional model of Earth's crust composed of a sealing layer at the hypocentre depth which is penetrated by the earthquake fault and releases fluid from a relatively low-permeability lower crust. This simple model is capable of explaining the observations, including the short travel time of the flow pulse from 8 km depth to the surface, long-term flow increase and its subsequent slow decay. Our model is consistent with other analyse of the 2014 aftershocks which attributes their anomalous character to exponentially decreasing external fluid force. Our observations and model hence track the fluid pressure pulse from depth where it was responsible for aftershocks triggering to the surface where a significant long-term increase of CO2 flow started 4 days later.

The Central Apennines are affected by frequent earthquakes of moderate magnitude that occur mainly within the upper part of the crust at depths of

For more than 20 years, seismohydrological investigations have been undertaken at the mineral aquifer system of Bad Brambach (Vogtland, Germany). Two strong swarm earthquake series in 2000–2001 and 2008–2009 at the Nový Kostel epicentre (Czech Republic, 10 km E of BB) have enabled for the first time a comparison of seismological and groundwater hydraulic features in a semi-quantitative way. In spite of their similar spatial distribution in 2001 and 2008, the earthquake foci of each swarm migrated differently through time, horizontally as well as in depth. The seismic energy of the 2008–2009 events was released predominantly within 1 month, in contrast to 2000–2001 when it occurred over 3 months. The main distinctive features of each are seen in the hydraulic pressure anomalies which accompanied the earthquake swarms: number, shape, and progression (duration) of the anomalies. The comprehensive hydraulic data, with high temporal resolution, suggest that fluid triggering dominated not only the earthquake initiating phases. In particular, the long-lasting seismicity of the 2008–2009 swarm can be attributed to a continued triggering of weak earthquakes by over-pressured deep fluids. Here, the remaining static strain was obviously not sufficient to generate strong earthquakes as at the beginning of the earthquake swarm periods. Furthermore, the enduring high fluid pressure in 2009 could also indicate a continuation of the long-term gas flow increase observed at several gas outlets in the Vogtland/NW Bohemia region between 1998 and 2008. However, it is not possible at present to derive a systematic relationship between anomaly occurrence and seismic activity, as generally proposed in the context of earthquake prediction discussion.

The Miano borehole, 1047 m deep, is located close to the river Parma in the Northern Apennines, Italy. A measuring station has been installed to observe the discharge of fluids continuously since November 2004. The upwelling fluid of this artesian well is a mixture of thermal water and CH4 as main components. In non-seismogenic areas, a relatively constant fluid emission would be expected, perhaps overlaid with long term variations from that kind of deep reservoir over time. However, the continuous record of the fluid emission, in particular the water discharge, the gas flow rate and the water temperature, show periods of stable values interrupted by anomalous periods of fluctuations in the recorded parameters. The anomalous variations of these parameters are of low amplitude in comparison to the total values but significant in their long-term trend. Meteorological effects due to rain and barometric pressure were not detected in recorded data probably due to reservoir depth and relatively high reservoir overpressure. Influences due to the ambient temperature after the discharge were evaluated by statistical analysis. Our results suggest that recorded changes in fluid emission parameters can be interpreted as a mixing process of different fluid components at depth by variations in pore pressure as a result of seismogenic stress variation. Local seismicity was analyzed in comparison to the fluid physico-chemical data. The analysis supports the idea that an influence on fluid transport conditions due to geodynamic processes exists. Water temperature data show frequent anomalies probably connected with possible precursory phenomena of local seismic events.

SUMMARY Earthquake swarms occur mostly in regions with CO2-enriched pore fluids. It is generally accepted that both geodynamic stress accumulation and critical pore fluid pressures act as a triggering mechanism for most seismic events. The new thesis presented here is that hydrothermal alteration processes in fault zones help facilitate the shear failure propagation due to mechanical weakening and dissolution of the wall rock, in addition to the normal shear stress and fluid overpressure. The basic idea that stress corrosion cracking results from chemical weakening and comminution has been discussed for many years. However, it has not yet been applied to explain the earthquake swarm phenomenon. Studies of extensive alteration as well as the latest investigations of CO2 sequestration give evidence that these high dissolution rates of wall rock in contact with an acid fluid phase exist in seismogenic fault zones. Several indications support the assumption that in the Vogtland/NW Bohemia region, the weakening of stressed fault zones by hydrothermal alteration could take place at seismogenic depths and could generate earthquake swarms. Investigations of quartz samples from the fracture zones by means of cathodoluminescence as well as spatiotemporal analysis of seismicity and numerical modelling of alteration-induced earthquake swarms support this hypothesis.

Over the last 15 years, there has been an increase in the 3He/4He ratios (Ra) at gas emission sites including springs (liquid-dominated) and mofettes (gas-dominated) in the Vogtland (Germany) and NW Bohemia (Czech Republic), indicating an active magmatic process. The highest Ra value (6.2) was measured at the mofette Bublak. Continuous CO2 flow records at Bad Brambach mineral springs (Vogtland) and Cheb Basin mofettes show a significant and enduring increase in gas flow. This increase ranges from 1.6% at Schillerquelle spring, Bad Brambach, and 61% per year at mofette Bublak. Calculated gas flow ratios between the individual emission sites not only emphasize the greater increase in gas flow over time at the Cheb Basin mofettes compared with the Bad Brambach springs (factor 2.1 to 2.6) but also show a uniform gas flow behaviour within both emission areas. Using simplified models, it is demonstrated that long-term gas flow measurements reveal a gas-hydraulic parameter, the effective cross-sectional ratio, to compare the near-surface gas-bearing fissures and cracks between the emission sites. Thus, the overall cross-sectional area of gas pathways at the mofette Soos is 13.2 times higher than at the Wettinquelle spring, indicating greater overall fissure widths for gas transport at the Cheb Basin mofettes than at the mineral springs. Comparison between the monthly fluctuations of free gas flow and dissolved CO2 at the Wettinquelle spring shows an inverse dependence of both parameters but without a temporal trend of dissolved CO2. This indicates that the mineral water body acts as a kind of buffer saturated by CO2 and being degassed more or less strongly, depending on the flow rate of the ascending free gas. The results suggest increased activity of the magmatic reservoir below the Cheb Basin, not only from the qualitative (3He/4He) but also from the quantitative (amount of magmatic CO2) perspective.

SUMMARY Cold CO2 gas emission sites in rainwater-filled pools, so called mofettes, are widely distributed all over Italy. Their gas reservoirs, mostly having a high CO2 content, have a magmatic and/or metamorphic origin. Temporal variations in fluid expulsions were observed at the mofettes of Caprese Michelangelo during the period from 2002 to 2005. These observations were made possible by using a new approach: photographic time-series. A first interpretation of these fluid expulsions was based on meteorological/hydrogeological explanations. However, our long-term observations show that these processes may merely be a side effect. The probable main reason for the anomalous emissions is the long-term variation in the long-distance fluid transport process from the reservoir induced by the local tectonic settings. In the northern part of the Alto Tiberina Fault, a fault intersection was reactivated by a seismic sequence which started on 2001 November 26, and continued for approximately four months. The magnitude of the main shock was MW= 4.6. As revealed by the drilling of a deep borehole, dug in the direct vicinity, overpressurized fluids trapped at a depth of 3700 m could be activated as a consequence of the improved transport conditions, that is, the fracture apertures that materialized as a result of the rupture process. A migration of the hypocentres towards the surface provides hints of a possible pore pressure diffusion process. The consequence is an increased fluid transport to the mofettes. The first indications of anomalous fluid expulsions at the mofettes of Caprese Michelangelo were detected 18 months after the seismic events.

Wahrend und nach der Rekonstruktion der Wettinquelle in Bad Brambach im Jahre 1999 wurden umfangreiche Untersuchungen zur Tritiumkonzentration und der spezifischen Leitfahigkeit des Quellwassers durchgefuhrt, die eine Zunahme der Sensitivitat hydrochemischer Parameter der Mineralquelle gegenuber Druckschwankungen im Grundwasserleiter belegen. Mischungsberechnungen auf Basis der spezifischen Leitfahigkeit zeigen, dass im speziellen Fall kurzfristig zufliesende oberflachennahe Grundwasser mithilfe der Tritium-Altersverteilung allein nicht identifiziert werden konnen. In diesem Zusammenhang konnten eine Mischwasserkomponente mit ca. 4 TU in geringer Tiefe sowie an einer benachbarten Tiefbohrung ein tritiumfreies Mineralwasser in 135 m Tiefe nachgewiesen werden. Zumischungen jungerer Anteile bei hydrologischen Extremereignissen beeinflussen vorwiegend die erstere Komponente. Ungeachtet der Fassungssanierung sind die langfristig herausgebildeten balneologisch-hygienischen Eigenschaften des Wasser der Wettinquelle praktisch unverandert geblieben. Dazu tragt nicht zuletzt der konsequente Grundwasserschutz vor Ort bei.

Since 1989, hydrological, geochemical, and isotope investigations are accomplished at springs of the Upper Vogtland (Germany). The results give evidence of a fluidal response of the mineral spring ‘Wettinquelle’ (formerly: ‘Radonquelle’) Bad Brambach to the seismogenic processes in the swarm quake area of Nový Kostel (distance: 10 km), the most seismically active area in the region. In 1999, the measuring network was extended to groundwater drillings around the Wettinquelle, and multiparameter stations were installed at mofettes SW and S of the Nový Kostel area. Beginning at the end of August 2000, the strongest swarmquake series compared with the 1985/86 swarms occurred in the area of Nový Kostel. Hydrological and hydrochemical measurements show an anomalous behaviour of several parameters such as groundwater level, hydrostatic pressure, and free gas flow beginning at the end of July 2000, and partially, of a duration up to the first strong events of the autumn 2000 swarm. These precursor phenomena were the result of an increased fluidal pressure in the ground before the earthquakes. They were visible as higher static water levels in a gauge well and a stronger degassing of the mineral spring ‘Wettinquelle’. The anomalies confirm our co-seismic hydrogeological observations of the last 10 years at Bad Brambach, as well as our model conception of anomaly generation due to fluidal pressure pulses [Pure. Appl. Geophys. 157 (2000) 1621]. Furthermore, co- and post-seismic effects of hydrological and geoelectrical parameters were recorded in the mofette area of Soos and Bublak (Czech Republic).

Time dynamics of self-potential, geochemical and meteorological parameters, simultaneously recorded in a CO 2 degassing area at Soos, NW-Bohemia (Czech Republic), have been investigated. The power spectra, behaving as power-law function of the frequency, show the presence of colored-noise-type dynamics. The Higuchi analysis reveals the observed geophysical signals to have the property of fractal curves, with the identification of different scaling regimes. The Detrended Fluctuation Analysis, removing trends and non-stationarities, has shown that the signals present clear fingerprints of long-range correlated fluctuations.

Scaling properties of self-potential and carbon dioxide flow rate data, concomitantly recorded in a CO 2 degassing area at Soos, Bohemia (Czech Republic), have been investigated by means of several fractal tools. The power spectra, behaving as power law function of the frequency, show the presence of colored noise-type dynamics. The Higuchi analysis reveals the self-potential and flow signals to have the property of fractal curves. The variograms, analyzing time-scales stretching from one hour to almost 50 hours, reveal the presence of approximately three time-scaling ranges, characterized by different features in terms of persistence of the processes underlying the signals.

—Extensive hydrogeological, geochemical, radiometric and hydro-isotope investigations in the Vogtland region, Germany, since 1989 suggest a fluid connection between a special epicentral area (focal depth: 3–15 km; ML < 5) and a mineral spring at Bad Brambach. Twenty-six hydrogeochemical anomalies are related to earthquakes/swarmquakes of that epicentral area near Novy Kostel (CZ) during the last 9 years. The anomalies were originated by a slug-flow process in the fluid-filled fracture system near the surface. The gas component of the observed fluid (99 vol. % CO2) is of upper mantle/crustal origin. The fluid transport pathway to the surface is the seismically active Marianske Lazne fault zone. The interpretation suggests an influence of the fluid system due to earthquake preparation processes.

For some years, the Saxon Academy of Sciences at Leipzig (SAW) is engaged in the research project ‘Contributions to Environmental Research by means of Radiometric-Geochemical Methods’ in the Vogtland area (Germany). The main goal is to investigate the hydrogeological and hydrochemical parameters of mineral springs in that region and their interrelations. Here, the high CO2degassing rates are of particular interest. The isotopic signature of these gases indicates an anomalous high mantle/crust contribution (Weinlich et al., 1999). A further geoscientifically important phenomenon of this region is the high seismicity, in particular the Vogtland/NW Bohemian earthquake swarms. Therefore, we have tried to use the mantle-originated fluids as transport media for information from the seismogenic horizons.

Coseismic geochemical variations have been detected in some gaseous vents and natural springs during the last seismic crisis occurred in Umbria region (Central Apennines), that started on September 26th, 1997 with several moderate earthquakes (up to M1 5.8). The results of chemical analyses performed on both gas and water samples taken at a weekly rate, combined with analyses on continuous gas flow rate nearby San Faustino site, suggest that the variations can be interpreted as possible consequence of the crustal permeability changes induced by earthquake shaking.

Addition of sulfur dichloride to tetrachlorocatechol-bisallylether (1) yields the 9- and 10-ring thia crown ether derivatives2 and3, respectively, together with the dithia-18-crown-6-ether4. The 10-membered ring compound3 represents the first thia macrocycle containing bothMarkovnikov andanti-Markovnikov constitution of the β-chloro-thio structural segments in the same molecule. By1H and13C NMR spectroscopy, equal amounts of two preferred conformers of the only isolated diastereomer of3 were observed at temperatures below −50°C. The signals were assigned to these conformers using COSY, HETCOR, and phase sensitive NOESY spectra at low temperatures. The preferred conformations and the relative configuration were determined using the different effects of γ gauche -and γ anti -positions in13C NMR chemical shifts and analyzing vicinal3 J H,H coupling constants. These results were confirmed by molecular mechanics calculations.

Bis-(1-chloro-3-phenoxy-prop-2-yl)-sulfanes – Nucleophilic Displacement and Regiochemistry. Separation and Assignment of Diastereomers. Synthesis of Diastereomerically Pure Trithiacycles The title compounds 1 were substituted by a series of O-, N- and S-nucleophiles (H2O solvolysis, AgOAc, NaN3, KSCN, NaSPh, thiourea). A strong tendency to β-elimination of HCl depending on the kind of the attacking nucleophile was found. In most cases no regioisomerization could be detected in the isolated products of the nucleophilic displacement. Best results were obtained with sulfur nucleophiles. The separation of the diastereomeric mixture of the p-kresyl derivative 1b into the individual diastereomers 1bA and 1bB in a preparative scale was achieved. These 3-thia-1,5-dichlorides and several products of substitution could be assigned to the meso- or (±)-form by examination of the stereochemistry and symmetry of the corresponding sulfoxides. The 1,5-dimercapto derivatives 8 are convenient as structural units for the synthesis of diastereomerically pure cis- or trans-disubstituted trithiacycles e.g. 15bA, 15bB. The (±)-form of the 4,6-disubstituted 2,5,8-trithia[9]-(2,6)-pyridinophane 16bA was characterized by X-ray crystal structure determination.

The interpretation of long term radon measure-ments in a spring located in Vogtland shows a significant relationship to the seismicity of a region close to the sampling point. A statistical check was performed in order to identify the anomaly-generating area. The cause for this relation is emission of mantle originated gases (including CO2) influenced by tectonic processes in the crust.

Investigations on the Chemistry of 3-Chloromethyl-3-methyl-2,3-dihydro-1,4-benzoxathiines A series of 3-chloromethyl-2,3-dihydro-1,4-benzoxathiines 3 were prepared by the reaction of several β-methallylphenylethers 1 with sulfur dichloride. In some cases intermediate sulfenyl chlorides 2 were isolated and characterized as substituted thiazolidin-2-ones. The thermal regioisomerization of selected sulfenyl chlorides and one of the thiazolidinone products was achieved. Starting from 3-chloromethyl-2,3-dihydro-1,4-benzoxathiine 3o several derivatives were obtained by nucleophilic displacement at the 3-chloromethyl position, activated by S-3-neighboring group partizipation. The structure of the 3-acetoxymethyl derivative was determined by x-ray crystal structure analysis. Further special derivation with selected chiral reagents led to diastereomeric compounds. The separation of the diastereomers by crystallization and chromatography was attempted. HPLC-separation was achieved in one case.

By way of thermolysis mass spectrometry it was shown that HSiCl 3 and MeHSiCl 2 decompose in the lower temperature region by hydrogen abstraction. To a small extent, methyl or chlorine groups as well as HCl are eliminated from MeHSiCl 2 . α-Eliminations become possible above 800°C. The disilanes Si 2 Cl 6 , Me 2 Si 2 Cl 4 and Me 3 Si 2 Cl 3 are cleaved heterolytically to give chlorosilylenes and chlorosilanes below 500°C, whereas above 700°C redistribution and homolytic fission may successfully compete or even dominate. These unimolecular reactions may also be helpful in the evaluation of initial steps in bimolecular decompositions of silicon compounds.

The results of continuous radon measurements in soil air and the water of a mineral spring at Bad Brambach are presented. They are discussed in connection with meteorological, hydrological parameters, and seismic events with magnitudes

[1] The combination of the latest geophysical instruments and geochemical methods applied to the arc volcanism (Aeolian Islands, Italy) has given new insights on the role of active tectonics on fluids migration. A continuous monitoring of the hydrothermal system off the island of Panarea has shown contemporaneous modifications of the vented fluids and the seismic activity of the nearby Stromboli volcano. The almost contemporary start of the last volcanic crisis at Panarea and Stromboli in 2002, besides the contemporary variation of the 3 He/ 4 He ratios at both the islands and the large number of submarine crater-shaped structures at Panarea, bears testimony to interconnections between the volcanic edifices. To confirm a tectonic drive of magmatic fluids over volcanic arcs implies that episodes of volcanic unrest can be triggered by the tectonic activity increasing the volcanic risk for the whole area, and this might be the case of the Stromboli-Panarea volcanic complex.

A New Group of Compounds Derived from Nereistoxin - Synthesis of Bis-dimethylamino-tris-disulfanes The reaction of organo-thiosulfates, BUNTE-salts, with mercaptans is a convenient synthesis of disulfanes. Similarly bis-BUNTE-salt 7 and tert. butyl mercaptan give bis-disulfane 5c [9]. By treating 7 with several aliphatic mercaptans we found the formation of the tris-disulfanes 8a–d in preparative amounts in addition to the bis-disulfanes 5a–d expected. This reaction was investigated. The preparation of the compounds 8 is described and a proposal is given for a mechanism of the formation of 8 as a thiol-disulfide-interchange.

In this work we analyze the geoelectrical and geochemical time series jointly recorded by means of Tramutola station during the period January 1995–September 1996. Since 1991 a research activity devoted to the analysis of geophysical and geochemical time series measured in a test site located in Southern Italy has been carried out. After a preliminary screening of spatial and temporal patterns of geochemical and geophysical phenomena observed in the investigated area, some multiparametric automatic stations, able to detect possible precursory phenomena, have been set up close to anomalous fluid emissions in Basilicata (Italy). The stations are equipped with sensors suitable for CO 2 , 222 Rn, electrical conductivity in water, temperature and self-potential. The main aims of this work are: a) to obtain a complete time series of possible precursory parameters; b) to apply statistical methods to discriminate anomalous patterns from background noise; c) to link geophysical and geochemical signals; d) to evaluate the possible correlation between anomalous patterns in precursory parameters and the local seismic activity.

Der Einflus der Reaktionsbedingungen und des Losungsmittels auf die Molmassenverteilung von Polysilanen, hergestellt durch Umsetzung von Diorganodichlorsilanen mit Natrium, wurde untersucht. Einsatz von Paraffinol als Solvens verkurzt die Reaktionszeten und liefert, wie fur (MePhSi)n naher studiert, auch in Mischungen hohermolekulare Produkte. Die beobachteten Effekte lassen sich durch im wesentlichen diffusionskontrollierte Oberflachenreaktionen an Natrium erklarren. The influence of reaction conditions and solvent composition on the molecular weight distribution of polysilanes ob- tained from diorgano dichlorosilanes and sodium dispersions is studied. Use of paraffin oil as the solvent reduces the time of reaction and furnishes higher molecular weight products as shown for (MePhSi)n even in mixtures containing small contents of paraffines. The observed effects may be explained by predominant diffusion-controlled reactions on the sodium surface.

Bis-(o-halophenoxy)silane reagieren mit Natrium nach Metallierung im Sinne einer raschen intramolekularen [1,3]-carbanionischen Umlagerung zu den Natriumsalzen der Bis-(o-hydroxyphenyl)silane (R1R2Si(o-C6H4ONa)2; R1 = Me, OMe…). Diese lassen sich durch Protolyse in die freien Phenole uberfuhren oder im Eintopfverfahren mit reaktiven Halogenverbindungen verestern und verethern. [1.3]-Carbanionic Rearrangements. Synthesis of Bis-(o-hydroxyphenyl) silane Derivatives Bis-(o-halophenoxy)silanes react via metallation in a fast two step [1.3]-carbanionic rearrangement to the sodium salts of the bis-(o-hydroxyphenyl)silanes (R1R2Si(o-C6H4ONa)2; R1 = Me, OMe…). These are protolyzed to the free phenols or are giving ethers and esters by reacting with reactive halogen compounds in an one pot reaction.

Bis-(o-halogenoaroxy)silane reagieren mit Natrium nach Metallierung im Sinne einer raschen zweifachen [1,3]-Umlagerung zu den Natriumsalzen der Bis-(o-hydroxyaryl)-silane. Im Eintopfverfahren lassen sich diese mit Organoelementhalogeniden des Siliciums, Phosphors und Arsens zu den Titelverbindungen der allgemeinen Formel R1R2Si(C6H4O)2E (E = SiR2, P(Y)R, As(Y)R) cyclisieren. Den NMR-spektroskopischen Untersuchungen entsprechend wird die Bildung eines Konformeren bevorzugt. Synthesis and NMR Spectroscopic Investigations of Dibenzo [d,g]-1,3-dioxa-2-element-6-silocine Bis-(o-halogenoaroxy)silanes react with sodium via metallation and a fast two-step [1.3]-rearrangement to the sodium salts of bis(o-hydroxyaryl)silanes. These are cyclized in a one-pot-reaction with element halides of silicon, phosphorus and arsenic to the title compounds of the general formula R1R2Si(C6H4O)2E (E = SiR2, P(Y)R, As(Y)R). One conformer is prefered according to N.M.R. spectroscopical investigations.

This paper presents the preliminary results analysing the correlation between local seismicity and geoelectrical, hydrogeological and geochemical signals concomitantly recorded in Basilicata Region, one of the most seismically active areas in Southern Italy. The signals were recorded by two stations: Tito and Tramutola. Tito station measures vertically the Self-Potential field (SP) by an array of five no-polarizable electrodes equally spaced with the common electrode at 20 m depth as well as water-level, water-temperature and electrical-conductivity. Tramutola station measures self-potential signals in soil surface, gas flow and water temperature in a thermal-water well, as well as atmospheric barometric pressure and ambient temperature. Correlations were found between the sharp variability of the signals recorded by both stations and the seismic sequence that occurred on September 3 to 4, 2004, allowing us to link these anomalies with the tectonic evolution of the investigated area.

Aktuelle Ergebnisse auf dem Gebiet niederkoordinierter Si-Verbindungen wurden auf einem ersten Workshop fur Nachwuchschemiker in Greifswald vorwiegend von Doktoranden und Diplomanden vorgetragen. Nach Einfuhrungen zum photoelektronen- und matrix-spektroskopischen Nachweis transienter Si-Spezies wurden synthetische Arbeiten vorgestellt.