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Emissions from wind turbines (WT) cover a wide range of infrasound and ground motions. When they are perceived as immissions by local residents, they can become a source of disturbance or annoyance. To mitigate such disturbances, it is necessary to better understand and, if possible, suppress WT-induced emissions. Within the project Inter-Wind we record and analyze ground motion signals in the vicinity of two wind farms on the Swabian Alb in southern Germany, simultaneously with acoustic and meteorological measurements, as well as psychological surveys done by cooperating research groups. The investigated wind farms consist of 3 and 16 WTs, respectively, and are located on the Alb peneplain at 700–800 m height, approximately 300 m higher than the two municipalities considered in our study. Our main aim is to better understand reasons why residents may be affected from WT immissions. Known ground motions include vibrations due to eigenmodes of the WT tower and blades, and the interaction between the passing blade and the tower, causing signals at constant frequencies below 12 Hz. In addition, we observe signals in ground motion recordings at frequencies up to 90 Hz which are proportional to the blade-passing frequency. We can correlate these signals with acoustic recordings and estimate sound pressure to ground motion coupling transfer coefficients of 3–16.5 µms-1Pa-1. Sources for these emissions are the WT generator and possibly the gearing box. The identification of such noise sources can help to find measures to reduce disturbances in order to increase the public acceptance of WTs. Residents perceive more disturbance at the location where the wind farm is closer to the municipality (approximately 1 km). However, there is also a major railway line which produces higher vibration and infrasound signal amplitudes compared to the WTs. Along the measurement lines the decay rate of the WT-induced ground motions is determined for a damping relation proportional to 1/rb. We find frequency-dependent b values for different scenarios at our geological setting of Jurassic limestone on marl, sandstone, and Quaternary deposits. These damping relationships can be used to estimate emissions in the far field and to plan mitigation strategies.

Deep low-frequency seismic events are detected in the East Eifel Volcanic Field (EEVF) since 2013. To well detect and locate such events the Deep Eifel Earthquakes Project - Tiefe Eifel Erdbeben (DEEP-TEE) started in July 2014 which now is composed of ca. 10 permanent and 15 mobile recording stations. Up to now, the DEEP-TEE seismic dataset contains eight years of continuous seismic records and the network has been reconfigured and continuously developed to achieve an optimum configuration regarding detection and location of seismic events.In order to detect the weak deep low-frequency (DLF) events we developed a seismic event detector and found ca. 330 localizable DLF events in 2014-2021. The DLF hypocenter distribution outlines a near-vertical structure close to the Laacher See Volcano (LSV) which erupted about 13,079 years ago. The hypocenters are as deep as ca. 45 km, close to the assumed lithosphere-asthenosphere boundary, and reach to about 5-8 km depth. Most events occur close to the Moho and in the lower crust what is interpreted as magmatic underplating and deep crustal intrusion. In the same depth range but further to the west, we find seismic reflections with a negative polarity. These are also interpreted as magmatic pockets in the lower crust and the Moho region.We try to estimate the mass flux (magma and volatiles) which is related with the seismicity. For this we apply Aki et al.'s model (JVGR, 1977) for describing the magma movement (a so-called chain of cracks connected by narrow channels) and estimate the related magma intrusion volume rate in the EEVF lithosphere. We assume an initial set of model parameters and evaluate the sensitivity and stability of the modelling results by allowing a reasonable range of each individual input parameter. Our results give an estimate of about 2,000-16,000 cubic meters of melt per year which is transported in the lithosphere.

Persistent microseismicity in the East Eifel Volcanic Field occurs along the Ochtendung Fault Zone (OFZ) just SE of Laacher See Volcano. In addition, deep-low-frequency earthquakes close by are a strong indication for active magmatic processes. No surface expression is known for the OFZ, therefore an active seismic study was conducted in the summer 2021 aiming to detect the near-surface structure of the fault.The survey follows a line nearly perpendicular to the assumed fault orientation. The total length of the survey is 4,500 m with 5 m geophone distance and a maximum offset of 1000 m. Additional to these vertical component geophones, 3-component sensors were deployed at several sites along the profile in order to record far offsets. A drop-weight served as a seismic source.1,022 shots lead to a total of more than 225,000 channels with maximum offsets of up to 1km, if including the 3-component sensors even up to 5km. Standard QC procedures and the stacking of the single shots at each shot point was done. The data set comprises 177 shot gathers with up to 221 receivers active at the same time. On these data the first onset P-wave arrivals were determined resulting in more than 35000 picks.The refraction tomography uses an innovative inversion technique harnessing the power of a transdimensional, hierachical Markov chain Monte Carlo (McMC) algorithm without the need of a priori assumptions. The number of Voronoi cells describing the Earth structure model and the level of data noise is automatically determined during the inversion process. The forward modelling is performed by a fast, finite-difference based eikonal solver. Starting several hundred McMC-chains across multiple CPU-cores leads to the parallelism needed for efficient sampling of the model space, thus computing of a refraction tomography 2-D Earth structure model including its uncertainty.We achieve a good resolution in depth down to about 200 m throughout our model. The thickness of the tephra layer covering the Rhenish shield is increasing from SW (few meters) to NE (80 m) along the profile. Further studies are still needed to illuminate the shallow structure of the OFZ.

Monitoring crustal movements is essential to volcanic hazard assessment in areas of active volcanism. These surface movements occur on a wide range of time scales and wavelengths. However, the origin of crustal movements is not always associated with volcanic activities, particularly in areas with rigorous human activities (i.e., ground water extraction). It is challenging yet critical to distinguish between the ongoing volcanic and anthropogenic activities. In this study, we focus on the East Eifel Volcanic Field, which consists of multiple active Quaternary volcanoes. We report areas of uplift and subsidence 2-3 km away from each other near the Laacher See volcanic crater (2-3 km distance), and investigate the mechanisms responsible for the reversed deformation in such close proximity.PS-InSAR measurements by the BodenBewegungsdienst Deutschland (BBD) show notable ground displacements in this area for the period between 2014 and 2019. The deformation is clearly mapped by three different tracks of the Sentinel-1 satellite – two ascending and one descending, which confirms the robustness of the signal being detected by PS-InSAR. The main deformation is round in shape, and the rates peak up to 10 mm per year in line-of-sight (LOS) for the uplift area near the village Glees and reach down to -4 mm LOS for the subsidence zone in the vicinity of the village Wehr. To investigate the likely mechanism responsible for the ground displacements, we model the crustal movements with two spherical pressure point sources (i.e., the Mogi sources) simultaneously using a combined global and local optimization scheme. In the inversion, we search for the optimal combinations for a set of four parameters (latitude, longitude, depth and volume) for each Mogi source. The global optimization is achieved by Multi-Level Single-Linkage algorithm and we use the PRAXIS algorithm to find the local minimum. We include all three tracks of data, of which the different satellite viewing geometries help stabilize the inversion.Our results show that the uplift trend in Glees can be explained by an additional volume of 13000 m³ per year at 530 m depth. The subsidence near Wehr can be best fitted by a decrease in volume of 1700 m³ per year at 340 m depth. The modelling results show a trade-off between depth and volume, however, the uncertainties are smaller for the subsidence source near Wehr. Residuals trending in SW-NE direction are observed at the Glees uplift area, and the relatively large parameter uncertainties for Glees uplift zone are likely due to sparse persistent scatters there. Given the shallow depth of the Mogi sources, we interpret the Glees uplift being predominantly associated with fluid refilling in the respective volume caused by former CO2 extraction. The subsidence around Wehr is linked to ongoing industrial CO2 extraction. Our study identifies anthropogenic factors that may cause ground deformation in an active volcanic region, and has implications for future volcanic hazard assessment.

Wind turbine (WT) ground motion emissions have a significant influence on sensitive measuring equipment like seismic monitoring networks. WTs permanently excite ground motions at certain constant frequencies due to the eigen modes of the tower and blades as well as the motion of the blades. The emitted waves have frequencies mainly below 10 Hz which are relevant for the observation of, e.g., local tectonic or induced seismicity. Furthermore, frequencies proportional to the blade passing frequency can be observed in ground motion data above 10 Hz, closely linked to acoustic emissions of the turbines. WTs are often perceived negatively by residents living near wind farms, presumably due to low frequency acoustic emissions. Therefore, similarities in ground motion and acoustic data provide constraints on the occurrence of such negatively perceived emissions and possible counter-measures to support the acceptance of WTs.We study ground motion signals in the vicinity of two wind farms on the Swabian Alb in Southern Germany consisting of three and sixteen WTs, respectively, which are of the same turbine type, accompanied by acoustic measurements and psychological surveys. A part of the measurements is conducted in municipalities near the respective wind farms where residents report that they are affected by emissions. Additional measurements are conducted in the forests surrounding the WTs, and within WT towers. The wind farms are located on the Alb peneplain at 700-800 m height, approximately 300 m elevated compared to the municipalities. Results indicate that WTs are perceived more negatively in the location where the wind farm is closer to the municipality (ca. 1 km) and where other environmental noise sources like traffic occur more frequently. At the location more distant to the WT (ca. 2 km), even though more WTs are installed, residents are affected less. To improve the prediction of ground motion emissions, instruments are set up in profiles to study the amplitude decay over distance, which is linked to the local geology.This study is supported by the Federal Ministry for Economic Affairs and Energy based on a resolution of the German Bundestag (03EE2023D).

The German Seismological Broadband Array (Deutsches Seismologisches Breitband Array [DSEBRA]) comprises 100 mobile seismological stations and can be deployed as a stand-alone network or in conjunction with other stations to build an even larger array. The first mission of DSEBRA was in the framework of the European AlpArray initiative. The aim of the project is to understand the deep structure, mantle dynamics, plate tectonics, its linkage to surface processes, and seismic hazard of the Alps–Apennines–Carpathians–Dinarides orogenic system. DSEBRA, purchased in the framework of the German Priority Program Mountain Building Processes in 4D, contributed to one-third of the temporary AlpArray seismic network (AASN). The stations are currently deployed in the Alpine foreland of Germany and Austria, in the high Alps of Austria and Italy, and in the Pannonian basins of Hungary. The stations are equipped with state-of-the-art technology, thus allowing to acquire high-quality broadband data in real time. In this article, we present the current station deployment within the AASN, describing the equipment and its handling. Furthermore, we discuss the data quality and perform noise analyses. In conclusion, DSEBRA stations provide excellent data and are very well suited for deployment in national or international seismological experiments.

In order to advance the expansion of onshore wind energy, wind turbines (WTs) must be erected in often complex terrain. The orography and the associated meteorological conditions, as well as the complex propagation of sound and ground motion waves can lead to increased annoyance of residents. Here a joint investigation of residential noise reports, meteorological, acoustic and ground motion data together with operational parameters of a wind farm in southern Germany is presented, with the objective to assess the annoyance of residents affected by WT emissions. Once strongly annoyed residents had been identified, simultaneous measurements were conducted over a 2-month period while residents used a noise reporting app to document their annoyance. A combination of the data shows that WT-related signals can be detected by acoustic and ground motion measurements in the vicinity of the WTs and, to a lesser extent, at the residential sites. In addition, background noise can be identified well. The app data indicates higher complaint rates in the early morning, evening and night hours. Changes in rotation rate seem to be the cause of annoyance as well as high rotation rates. These findings can be used to adjust WT operation in order to decrease immissions.

The region around the town of Albstadt, SW Germany, is one of the most seismically active regions in Central Europe. In the last century alone three earthquakes with a magnitude greater than five happened and caused major damage. The ruptures occur along the Albstadt Shear Zone (ASZ), an approx. 20-30 km long, N-S striking fault with left-lateral strike slip. As there is no evidence for surface rupture the nature of the Albstadt Shear Zone can only be studied by its seismicity.To characterize the ASZ we continuously complement the earthquake catalog of the State Earthquake Service of Baden-Württemberg with additional seismic phase onsets. For the latter we use the station network of AlpArray as well as 5 additional, in 2018/2019 installed seismic stations from the KArlsruhe BroadBand Array. We inverted for a new minimum 1D seismic velocity model of the study region. We use this seismic velocity model to relocalize the complemented catalog and to calculate focal mechanisms. The majority of the seismicity happens between the towns Tübingen and Albstadt at around 9°E in a depth range of about 1.5 to 16 km and aligns north-south. Additionally, we see a clustering of events at the towns Hechingen and Albstadt. The dominating focal mechanism is strike-slip, but we also observe minor components of normal and reverse faulting.Our results image the ASZ by its mainly micro-seismic activity between 2011 and 2018 confirming the N-S striking character, but also indicating a more complex fault system.We thank the State Earthquake Service in Freiburg for using their data (Az. 4784//18_3303).

Vorgestellt werden Ergebnisse aus experimentellen und numerischen Untersuchungen bezuglich des Leistungseintrages einer koaxialen Anordnung aus Schrauben- und Wendelruhrer. Diese Kombination ist fur den Einsatz in komplexen Anwendungen bei hoherer Viskositat und bei Vorliegen von strukturviskosem Verhalten geeignet.

In Fermentationsanlagen konnen tierische Zellen durch mechanische Beanspruchungen irreversibel geschadigt werden, wodurch die Produktivitat sowie die Produktreinheit sinken. Da solche Fermentationsprozesse haufig in Ruhrreaktoren bewerkstelligt werden, sind numerische und experimentelle Untersuchungen zur Klarung der physikalischen Effekte fur die Prozessgestaltung/-optimierung von Nutzen.

The syntheses of 1,8-diazacyclotetradeca-3,5,10,12-tetrayne (2a), its N,N′-dimethyl (2b), N,N′-diethyl (2c), N,N′-diisopropyl (2d), N,N′-diallyl (2e), and N,N′-dibenzyl (2f) derivatives were achieved in a one-pot procedure from primary amines and 1,6-dibromo-2,4-hexadiyne (4). Diffraction studies on single crystals of 2c−2f reveal a chair conformation with the substituents in the diaxial positions. The preference of the axial orientation of the substituents on the nitrogens in 2c−2f is due to several contributions: minimal synaxial 1,3 interactions of the NR bond and the lone pair with adjacent CH and CC bonds.

Reaction of Cp(PMe(3))IrPh(OH) (1) with nitriles is undetectably slow in benzene solution at room temperature. However, in the presence of Cp(PMe(3))IrPh(OTf) (2) (OTf = O(3)SCF(3)), the reaction is strongly catalyzed, leading to iridium(III) carboxamides Cp(PMe(3))IrPh[NHC(O)R] (6a-d) [R = C(6)H(4)CH(3) (6a), C(6)H(5) (6b), C(6)H(4)CF(3) (6c), CH(3) (6d)]. We propose that these transformations occur by initial displacement of the trifluoromethanesulfonate ("triflate") anion of 2 by a molecule of nitrile, leading to a nitrile-substituted iridium cation, [Cp(PMe(3))IrPh(NCR)](+) (10). Following this, the nucleophilic hydroxide group of 1 attacks the (activated) nitrile molecule bound in 10, leading (after proton transfer) to the iridium carboxamide complex. In the case of nitriles possessing hydrogens alpha to the cyano group, competitive loss of one of these protons is observed, leading to iridium C-bound cyanoenolates such as Cp(PMe(3))(Ph)Ir(CH(2)CN) (7). Protonolysis of carboxamides 6a-d with HCl yields Cp(PMe(3))IrPh(Cl) (9) and the free amides. A pronounced solvent effect is observed when the reaction between 1 and nitriles catalyzed by 2 is carried out in THF solution. The basic hydroxide ligand of 1 induces an overall dehydration/cyclization reaction of the coordinated aromatic nitrile. For example, the reaction of 1 with p-trifluorotolunitrile and a catalytic amount of 2 leads to the formation of 6c, water, [Ph(PMe(3))Ir[C(5)Me(4)CH(2)C(C(6)H(4)CF(3))N]] (12), and [Ph(PMe(3))Ir(C(5)Me(4)CH(2)C(C(6)H(4)CF(3))NH)]OTf (13). A mechanism to explain the formation of both 12 and 13 and the role each compound plays in the formation of the iridium carboxamides is proposed.

The conformations of azacyclodeca-3,8-diyne (4a) and its N-methyl (4b) and N-isopropyl (4c) derivatives as well as 1,6-diazacyclodeca-3,8-diyne (5a) and its 1,6-dimethyl (5b), 1,6-diisopropyl (5c),...

The preparation of N,N′-dialkyl- and N,N′-diaryl-1,6-diazacyclodeca-3,8-diynes was achieved by reaction of alkyl- or arylamines with 1,4-dihalobut-2-yne under dilution conditions in yields of 5–15%. The compounds synthesized by this procedure were the N,N′-dimethyl (2b), N,N′-diethyl (2c), N,N′-diisopropyl (2d), N,N′-di-tert-butyl (2e), N,N′-dicyclohexyl (2f), N,N′-diphenyl (2g), and N,N′-di-p-tolyl (2h) derivatives. The parent compound 2a was obtained in ca. 40% yield by heating 2d with α-chloroethylchloroformate (20). Using 1,9-dibromonona-2,7-diyne (10) and methylamine or isopropylamine, respectively, the corresponding N-alkyl-1-azacyclodeca-3,8-diynes 4b and 4d were synthesized under dilution conditions. By heating 4d with 20 we obtained 1-azacyclodeca-3,8-diyne (4a). As side products of the cyclization reactions the trimers 18 and tetramers 12 and 19 were isolated and characterized. N-methyl-1-azacycloundeca-3,9-diyne (14b) was prepared by reaction of 1,10-dibromodeca-3,8-diyne (13) with methylamine.

The reactions of 1,6-dialkyl-1,6-diazacyclodeca-3,8-diynes (9, a = CH3, b = C2H5, c = i-C3H7) with HCl, H2O and CH3OH have been investigated. The reaction of 9c with HCl selectively gives N,N′-diisopropyl-4-chloro-1,2,3,5,6,7-hexahydro-2,6-naphthyridine (13c) in quantitative yield. Investigation of this reaction at different temperatures allows the activation parameters for the process to be derived (ΔH≠ = 24 ± 1 kcal · mol−1, ΔS≠ = – 9 ± 2 cal · mol−1 · K−1). The regioselective reaction of 9c with methanol affords a quantitative yield of N,N′-diisopropyl-4-methoxy-1,2,3,4,5,6,7-hexahydro-2,6-naphthyridine (29c). Addition of water to 9a in the presence of H2SO4 gives N,N-dimethyl-7-oxo-1,2,3,4,5,6,7,8-octahydro-2,6-naphthyridine (28a) in low yields (15%). If the addition of water is carried out in the presence of Hg2+, the yield of 28a is increased considerably. The mechanisms of all three reactions are discussed and those involving electrophilic addition (AdE2) are favored.

The Pd-catalyzed rearrangement of 1,6-diisopropyl-1,6-diazacyclodeca-3,8-diyne ( 1b ) to N,N′-diisopropyl-3,3′-bispyrrole ( 2b ) in a one pot reaction involves forming two new CC bonds, cleaving one triple bond, two allylic rearrangements and two dehydrogenation steps.

The reactions of 1,6-dialkyl-1,6-diazacyclodeca-3,8-diynes (9, a = CH3, b = C2H5, c = i-C3H7) with HCl, H2O and CH3OH have been investigated. The reaction of 9c with HCl selectively gives N,N′-diisopropyl-4-chloro-1,2,3,5,6,7-hexahydro-2,6-naphthyridine (13c) in quantitative yield. Investigation of this reaction at different temperatures allows the activation parameters for the process to be derived (ΔH≠ = 24 ± 1 kcal · mol−1, ΔS≠ = – 9 ± 2 cal · mol−1 · K−1). The regioselective reaction of 9c with methanol affords a quantitative yield of N,N′-diisopropyl-4-methoxy-1,2,3,4,5,6,7-hexahydro-2,6-naphthyridine (29c). Addition of water to 9a in the presence of H2SO4 gives N,N-dimethyl-7-oxo-1,2,3,4,5,6,7,8-octahydro-2,6-naphthyridine (28a) in low yields (15%). If the addition of water is carried out in the presence of Hg2+, the yield of 28a is increased considerably. The mechanisms of all three reactions are discussed and those involving electrophilic addition (AdE2) are favored.

The conformations of azacyclodeca-3,8-diyne (4a) and its N-methyl (4b) and N-isopropyl (4c) derivatives as well as 1,6-diazacyclodeca-3,8-diyne (5a) and its 1,6-dimethyl (5b), 1,6-diisopropyl (5c),...

The preparation of two 1-thia-6-azacyclodeca-3,8-diynes is reported together with their spectroscopic and structural properties (X-ray structure).

The preparation of four 1,6-diazacyclodeca-3,8-diynes is reported together with spectroscopic and structural properties (X-ray structure).