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The hypnotic turbo-induction technique has been used for more than three decades for various indications in dentistry and medicine. The use of the technique is described step by step using therapeutic communication and hypnotic suggestions in a dento-surgical treatment of a 48-year-old adult man. In a 15-minute appointment, two maxillary third molars (wisdom teeth) have been extracted without interruptions/complications by a dental team in a private practice trained in dental/medical hypnosis. The hypnotic turbo-induction technique proved to be a successful application method for anxiety reduction/relaxation, pain relief as well as postoperative wound healing after the extraction of wisdom teeth, which had to be extracted due to a medical indication. Anxiety- and pain reducing effects were noted by the patient during and after the treatment; rapid wound healing was noted by the dental team at the follow-up appointment one week later in this case. The cooperation of the two dental professionals trained in hypnosis proved to be beneficial, especially when the dentist must concentrate on the dento-surgical treatment, the dental assistant can concentrate on both the patient and the hypnosis and to maintain the hypnotic state by additional suggestions. Clinical research is needed to further investigate the effects of the proposed hypnotic turbo-induction technique.

The Seebeck-coefficient (aka thermopower) is a less wide-spread parameter to determine constants for defect chemical models of semiconductor oxides. It is a measure for the charge carrier concentration. In contrast to the often investigated electrical conductivity, it has the benefit of being independent of the material geometry. BaFe0.7Ta0.3O3‐δ is known as a temperature-independent conductometric oxygen sensor material with perovskite crystal structure. The present work considers the Seebeck-coefficient as well as the electrical conductivity of bulk and thick-film BaFe0.89Al0.01Ta0.1O3‐ δ (BFAT10). Seebeck-coefficient and electrical conductivity were measured simultaneously between 600 and 950 °C under varying oxygen partial pressures from 10− 24 to 1 bar. BFAT10 thick films have been successfully deposited by the novel Aerosol Deposition Method (ADM) at room temperature on a special transducer. The electrical conductivity of thick-film sensors shows almost no temperature dependency but depends strongly on the oxygen partial pressure in the temperature range from 600 to 800 °C. An n-to-p-type transition was observed in the investigated oxygen partial pressure and temperature range. The defect parameters were derived from the experimental results and an initial defect model for BFAT10 is discussed. A hopping-type conduction mechanism is assumed due to the very low charge carrier mobility.

Calcium cobaltite is one of the most promising oxide p-type thermoelectric materials. The solid-state reaction (or calcination, respectively), which is well known for large-scale powder synthesis of functional materials, can also be used for the synthesis of thermoelectric oxides. There are various calcination routines in literature for Ca3Co4O9 powder synthesis, but no systematic study has been done on the influence of calcination procedure on thermoelectric properties. Therefore, the influence of calcination conditions on the Seebeck coefficient and the electrical conductivity was studied by modifying calcination temperature, dwell time, particle size of raw materials and number of calcination cycles. This study shows that elevated temperatures, longer dwell times, or repeated calcinations during powder synthesis do not improve but deteriorate the thermoelectric properties of calcium cobaltite. Diffusion during calcination leads to idiomorphic grain growth, which lowers the driving force for sintering of the calcined powder. A lower driving force for sintering reduces the densification. The electrical conductivity increases linearly with densification. The calcination procedure barely influences the Seebeck coefficient. The calcination procedure has no influence on the phase formation of the sintered specimens.

We present a new high-deposition-rate coating technique that allows us to produce at room temperature long thick films of MgB 2 on flexible steel substrates. Such a technique might give rise to new tapes with higher filling factors compared to the standard processed tapes. With the so-called aerosol deposition technique, MgB 2 films were prepared on Hastelloy substrates with commercially available ex situ-prepared MgB 2 powder (T C,onset of 38 K, JC of 3.8·10 3 A/cm 2 at 4 K and 1 T). Microscopic analyses yield nanocrystalline dense films with high film stresses. The as-deposited films have so far a superconducting transition temperature T C0 of 18.1 K and a critical current density J C up to 5·10 3 A/cm 2 at 4 K and self-field obtained.

Iron-substituted strontium titanate Sr(Ti,Fe)O 3 (STF) is a semiconducting oxygen sensing ceramic, and features a temperature independent conductivity at temperatures between 700 and 800 °C for the composition SrTi 0.65 Fe 0.35 O 3– δ (STF35). Aerosol deposition (AD) offers advantages as a means of producing thick films of this sensor material. In this work, aerosol co-deposition of ceramics (AcDc) was used to tune the functional properties of STF35 by incorporating alumina particles directly. Composite films of STF35:Al 2 O 3 with homogeneously distributed particle fractions were successfully deposited by AcDc. The conductivity of films was tunable over an order of magnitude with up to 60 volume percent alumina, and the temperature independent oxygen sensing behavior, as observed in bulk ceramics, was retained. Higher percentages of alumina decreased the conductivity further (up to four orders of magnitude) but the sensor response characteristic to oxygen disappeared.

The present study is focused in two directions. In the first part, BaFe(1-x)-0.01Al0.01TaxO3−δ (BFATx) thick films with a Ta content between 0.1 and 0.4 were manufactured using the novel room temperature coating method “aerosol deposition” (ADM), and its material properties were characterized to find the best composition of BFATx for temperature-independent oxygen sensors. The material properties “Seebeck coefficient” and “conductivity” were determined between 600 and 800 ∘C at different oxygen partial pressures. BaFe0.69Al0.01Ta0.3O3−δ (BFAT30) was found out to be very promising due to the almost temperature-independent behavior of both the conductivity and the Seebeck coefficient. In the second part of this study, films of BFAT30 were prepared on a special transducer that includes a heater, equipotential layers, and special electrode structures so that a combined direct thermoelectric/resistive oxygen sensor of BFAT30 with almost temperature-independent characteristics of both measurands, Seebeck coefficient and conductance could be realized. At high oxygen partial pressures (pO2 > 10−5 bar), the electrical conductance of the sensor shows an oxygen sensitivity of m = 0.24 (with m being the slope in the logσ vs. logpO2 representation according to the behavior of σαpO2m), while the Seebeck coefficient changes with a slope of −38 µV K−1 per decade of pO2 at 700 ∘C. However, at low pO2 (pO2 −14 bar) the conductance and the Seebeck coefficient change with pO2, with a slope of m = −0.23 and −21.2 µV K−1 per decade pO2, respectively.

Oxide-based materials are promising candidates for use in high temperature thermoelectric generators. While their thermoelectric performance is inferior to commonly used thermoelectrics, oxides are environmentally friendly and cost-effective. In this study, Cu-based delafossites (CuFeO2), a material class with promising thermoelectric properties at high temperatures, were investigated. This work focuses on the phase stability of CuFeO2 with respect to the temperature and the oxygen partial pressure. For this reason, classical material characterization methods, such as scanning electron microscopy, energy dispersive X-ray spectroscopy, and X-ray diffraction, were combined in order to elucidate the phase composition of delafossites at 900 &deg, C at various oxygen partial pressures. The experimentally obtained results are supported by the theoretical calculation of the Ellingham diagram of the copper&ndash, oxygen system. In addition, hot-stage X-ray diffraction and long-term annealing tests of CuFeO2 were performed in order to obtain a holistic review of the phase stability of delafossites at high temperatures and varying oxygen partial pressure. The results support the thermoelectric measurements in previous publications and provide a process window for the use of CuFeO2 in thermoelectric generators.

The gas sensing properties of resistive gas sensors of BaFe0.7Ta0.3O3-δ (BFT30) prepared by the so-called aerosol deposition method, a method to manufacture dense ceramic films at room temperature, were investigated. The electrical response of the films was investigated first under various oxygen concentrations and in a wide temperature range between 350 and 900 °C. Between 700 and 900 °C, the conductivity of BaFe0.7Ta0.3O3-δ (BFT30) depends on the oxygen concentration with a slope of almost 1/4 in the double-logarithmic plot vs. oxygen partial pressure. In addition, the sensor response is temperature independent. BFT30 responds fast and reproducibly to changing oxygen partial pressures even at 350 °C. The cross-sensitivity has been investigated in environments with various gases (C3H8, NO, NO2, H2, CO, CO2, and H2O) in synthetic air between 350 and 800 °C. BFT30 exhibits good sensing properties to NO between 350 and 400 °C in the range from 1.5 to 2000 ppm with a high selectivity to the other investigated gas species. Thus this semiconducting ceramic material is a good candidate for a temperature-independent oxygen sensor at high temperatures with the application in exhausts and for a selective nitrogen monoxide (NO) sensor at low temperatures for air quality monitoring.

In the field of thermoelectric energy conversion, oxide materials show promising potential due to their good stability in oxidizing environments. Hence, the influence of oxygen partial pressure during synthesis on the thermoelectric properties of Cu-Delafossites at high temperatures was investigated in this study. For these purposes, CuFeO2 powders were synthetized using a conventional mixed-oxide technique. X-ray diffraction (XRD) studies were conducted to determine the crystal structures of the delafossites associated with the oxygen content during the synthesis. Out of these powders, films with a thickness of about 25 µm were prepared by the relatively new aerosol-deposition (AD) coating technique. It is based on a room temperature impact consolidation process (RTIC) to deposit dense solid films of ceramic materials on various substrates without using a high-temperature step during the coating process. On these dense CuFeO2 films deposited on alumina substrates with electrode structures, the Seebeck coefficient and the electrical conductivity were measured as a function of temperature and oxygen partial pressure. We compared the thermoelectric properties of both standard processed and aerosol deposited CuFeO2 up to 900 °C and investigated the influence of oxygen partial pressure on the electrical conductivity, on the Seebeck coefficient and on the high temperature stability of CuFeO2. These studies may not only help to improve the thermoelectric material in the high-temperature case, but may also serve as an initial basis to establish a defect chemical model.

We have investigated the electrical transport properties of poly(3,4-ethylenedioxythiophen)/poly(4-styrene-sulfonate) (PEDOT:PSS) with PEDOT-to-PSS ratios from 1:1 to 1:30. By combining impedance spectroscopy with thermoelectric measurements, we are able to independently determine the variation of electrical conductivity and charge carrier density with PSS content. We find the charge carrier density to be independent of the PSS content. Using a generalized effective media theory, we show that the electrical conductivity in PEDOT:PSS can be understood as percolation between sites of highly conducting PEDOT:PSS complexes with a conductivity of 2.3 (Ωcm)−1 in a matrix of excess PSS with a low conductivity of 10−3 (Ω cm)−1. In addition to the transport properties, the thermoelectric power factors and Seebeck coefficients have been determined. © 2012 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys, 2012

In the field of thermoelectric energy conversion, oxide materials show promising potential due to their good stability in oxidizing environments. Hence, the influence of oxygen partial pressure during synthesis on the thermoelectric properties of Cu-Delafossites at high temperatures was investigated in this study. For these purposes, CuFeO2 powders were synthetized using a conventional mixed-oxide technique. X-ray diffraction (XRD) studies were conducted to determine the crystal structures of the delafossites associated with the oxygen content during the synthesis. Out of these powders, films with a thickness of about 25 µm were prepared by the relatively new aerosol-deposition (AD) coating technique. It is based on a room temperature impact consolidation process (RTIC) to deposit dense solid films of ceramic materials on various substrates without using a high-temperature step during the coating process. On these dense CuFeO2 films deposited on alumina substrates with electrode structures, the Seebeck coefficient and the electrical conductivity were measured as a function of temperature and oxygen partial pressure. We compared the thermoelectric properties of both standard processed and aerosol deposited CuFeO2 up to 900 °C and investigated the influence of oxygen partial pressure on the electrical conductivity, on the Seebeck coefficient and on the high temperature stability of CuFeO2. These studies may not only help to improve the thermoelectric material in the high-temperature case, but may also serve as an initial basis to establish a defect chemical model.