Electrical Conductivity

6 14 40 20 26 32 Titelbild Modellierungsergebnis: Isothermenflächen und Grundwasserströmungslinien als Ergebnis einer Simulation des Entwicklungszyklus des geothermisch genutzten Reservoirs Groß Schönebeck (In-situ-Geothermielabor des Deutschen GeoForschungsZentrums GFZ) über einen Zeitraum von 30 Jahren

The adsorption of asphaltenes on solid surfaces can be the precursor of deposition problems in oilfields. The prediction of adsorption thickness using conventional techniques, such as quartz crystal microbalance (QCM), is usually costly and time-consuming. Alternatively, the adsorption can be related to asphaltene characteristics in the bulk phase that are easier to determine. This study investigates the relationship between the adsorption thickness of asphaltenes on hydrophilic surfaces, such as gold, and their electrical conductivity in toluene within a range of concentrations where adsorption is diffusion-controlled. The method is based on the measurement of direct-current (DC) conductivity of petroleum fluids in toluene using the impedance spectroscopy (IS) method. An inverse relationship is established between the thickness of adsorbed rigid monolayer films on gold and the conductivity of particles in the bulk fluid. However, the relation does not hold for small asphaltene particles (d < 3 nm) because they tend to form non-uniform multilayers with possible viscoelastic characteristics.

Epitaxial growth of a metal (CoSi2)/insulator (CaF2) nanometer-thick layered structure on Si(lll) was demonstrated and the resistivity of CoSi2 epilayer in this structure was investigated. An epitaxial CoSi2 layer on CaF2 was obtained by the two-step growth technique, i.e. solid phase epitaxy with the epitaxial Si layer grown in the first step and Co deposited in the second step. This technique was shown to be effective to avoid the Co agglomeration on CaF2 layer observed in the co-evaporation of Si and Co. An epitaxial CaF2 layer was formed on CoSi2/CaF2 at low substrate temperature (450°C) with partially ionized and accelerated CaF2 beam, to avoid Co agglomeration in the CoSi2/CaF2 underlayer as well. Obtained results showed a single-crystalline nature in reflection high-energy electron diffraction (RHEED) and transmission electron microscopy (TEM) observations. The resistivity of a few nm-thickCoSi2 epilayers embedded by CaF2 has been investigated. We studied thickness and annealing temperature dependence of resistivity and showed that a minimum resistivity of 30~tD cm was obtained in a 2 nm-thickCoSi2 sample annealed at 860°C.

The magnetic field around the Moon has been successfully observed at a nominal altitude of ∼100 km by the lunar magnetometer (LMAG) on the SELENE (Kaguya) spacecraft in a polar orbit since October 29, 2007. The LMAG mission has three main objectives: (1) mapping the magnetic anomaly of the Moon, (2) measuring the electromagnetic and plasma environment around the Moon and (3) estimating the electrical conductivity structure of the Moon. Here we review the instrumentation and calibration of LMAG and report the initial global mapping of the lunar magnetic anomaly at the nominal altitude. We have applied a new de-trending technique of the Bayesian procedure to multiple-orbit datasets observed in the tail lobe and in the lunar wake. Based on the nominal observation of 14 months, global maps of lunar magnetic anomalies are obtained with 95% coverage of the lunar surface. After altitude normalization and interpolation of the magnetic anomaly field by an inverse boundary value problem, we obtained full-coverage maps of the vector magnetic field at 100 km altitude and the radial component distribution on the surface. Relatively strong anomalies are identified in several basin-antipode regions and several near-basin and near-crater regions, while the youngest basin on the Moon, the Orientale basin, has no magnetic anomaly. These features well agree with characteristics of previous maps based on the

Electrical resistivity tomography ͑ERT͒ has shown great promise for monitoring transient hydrologic processes. One advantage of ERT under those conditions is the ability of a user to tailor the spatial sensitivity of an ERT survey through selection of electrode locations and electrode combinations. Recent research has shown that quadripoles can be selected in a manner that improves the independent inversion of ERT data. Our ultimate interest lies in using ERT data along with measurements from other sensors, which typically can provide high-quality data from shallow regions of the subsurface, in a joint inversion. As a result, we do not consider the selection of quadripoles specifically for inde-pendent ERT inversion. Rather, we present an approach to focusthe spatial sensitivity of ERT surveys in specific subsurface regions with the assumption that those data, when interpreted along with other measurements that are sensitive to those regions, will lead to more complete hydrologic characterization. Because we are interested in monitoring rapid processes, our approach is designed to efficiently identify optimal quadripoles. This is achieved by separating the optimization from the inversion grid, significantly reducing computational effort. We extend our previous work to consider the use of both surface and borehole ERT electrodes and to consider the impacts of horizontally layered electrical conductivity conditions. Results confirm the ability of the method to focus survey sensitivity while showing the importance of incorporation of prior knowledge of the subsurface electric conductivity structure in designing optimal ERT surveys.

Epoxy resin will continue to be in the forefront of many thermoset applications due to its versatile properties. However, with advancement in manufacturing, changing societal outlook for the chemical industries and emerging technologies that disrupt conventional approaches to thermoset fabrication, there is a need for a multifunctional epoxy resin that is able to adapt to newer and robust requirements. Epoxy resins that behave both like a thermoplastic and a thermoset resin with better properties are now the norm in research and development. In this paper, we viewed multifunctionality in epoxy resins in terms of other desirable properties such as its toughness and flexibility, rapid curing potential, self-healing ability, reprocessability and recyclability, high temperature stability and conductivity, which other authors failed to recognize. These aspects, when considered in the synthesis and formulation of epoxy resins will be a radical advance for thermosetting polymers, with a lot of applications. Therefore, we present an overview of the recent finding as to pave the way for varied approaches towards multifunctional epoxy resins.

Anodic coupling of dithienylacetylene and dithienylacetylenes substituted with alkyl and alkoxy groups has been investigated in acetonitrile. The resulting polymers have been characterized by cyclic voltammetry, UV-Vis spectroscopy, electrochemical quartz crystal microbalance, in situ ESR and in situ conductivity. The degree of conjugation of the polymers is increased as the monomer oxidation potential is lowered, which occurs with alkyl-substitution and even more with alkoxy-substitution. Alkoxy-substitution in position 3 of the thiophene ring produces the dimer, whereas 4-subslitution yields an extensively crosslinked polymer. A regularly coupled polymer is obtained by 3,4-disubstitution with the ethylenedioxy group. The low conductivity (1 × 10-3 S cm-1) and the high unpaired spin density in the oxidized state of this polymer are explained by localization of charge and spin operated in the dithienyl moieties by the triple bonds.

Rapid advances in biosensors have recently been reported. This has been possible due to rapid growth in the development of new biomaterials such as conducting polymers, copolymers and sol gels etc and the reported improvements in sensing techniques. Biosensors are miniaturized devices employing biochemical molecular recognition as the basis for a selective analysis. The response generated as a result of biochemical reaction is detected by a transducer to give a signal (optical/electrical/thermal) that can be used with or without amplification for the estimation of the concentration of an analyte in a given test sample. Among the various biosensors, electrochemical sensors, especially amperometric biosensors presently hold a leading position.Due to specificity, portability, simplicity, high sensitivity, potential ability for real-time and on-site analysis coupled with the speed and low cost, biosensors have been projected to have applications in food analysis, environment control, clinical detection, drug and agriculture industries etc. Besides this, biosensors offer exciting opportunities for numerous decentralized clinical applications, ranging from emergency room screening, home self testing and alternative site testing, continuous and real-time in vivo monitoring. New generation of biosensors combining new bioreceptors with the ever-growing number of transducers is emerging. The present paper highlights some of the recent advances in the area of biosensors contributed by our laboratory.

A Pt/C heterojunction has been fabricated and tested as a conductometric hydrogen gas sensor. The carbon layer, deposited between planar Au substrate contacts using a filtered cathodic vacuum arc (with an applied substrate bias of -500 V), consisted largely of vertically oriented graphitic sheets. These sheets have good through-film electrical conductivity and contributed to a low device resistance of ~ 60 Ω. The Pt layer (of 3 nm thickness) was deposited using a Gatan Model 682 Precision Electron Coating System (PECS). A change in the device resistance of > 2% was exhibited upon exposure to 1 % hydrogen gas (in synthetic, zero humidity air) at room temperature. The time for the sensor resistance to decrease by 2 % under these conditions was 60 s and the baseline (zero hydrogen exposure) resistance remained constant to within 0.03% during and after the exposure tests.

Electrically conductive fabrics were produced by deposition of a thin film of doped polypyrrole on the surface of cotton fibres. In situ oxidative chemical polymerisation were carried out in aqueous solutions of pyrrole, oxidant and doping agents, at room temperature. Polypyrrole-coated fibres were characterized by Light Microscopy, SEM, EDX, FTIR and TGA. Moreover, fabric samples were also evaluated for moisture regain, electrical resistivity, heat generation and antibacterial activity. PPy alters the combustion process of cellulose fibres that maintain the fibrous shape after heating in air. Moreover, it seems that PPy is really an antibacterial agent, apart from the oxidant or dopant used. The results highlight potential applications as technical textiles with antistatic (low electrical resistance), heat generation, hygroscopy, antibacterial and high temperature resistance properties.

The uncertain conductivity value of skull and brain tissue influences the accuracy of the electroencephalogram (EEG) inverse problem solution. Indeed, when the assumed conductivity in the numerical procedure is different from the actual conductivity then a source localization error is introduced. When using traditional least-squares minimization methods, the number of electrodes in the EEG cap does not influence the spatial resolution. A recently developed reduced conductivity dependence (RCD) methodology, based on the selection of electrodes, is able to increase the spatial resolution of the EEG inverse problem. This paper presents the implications of the RCD method when using a large number of electrodes in the EEG cap on the spatial resolution of the EEG inverse solutions. We show by means of numerical experiments that in contrast to traditional methods, the RCD method enables to increase the spatial resolution. The computations show that the EEG hardware should be modified with as large as possible electrodes.

The conversion of wood-based fiberboard materials into crack-free, monolithic, porous hard carbons is of significant interest due to their ability to perform in a multifunctional capacity. Three varieties of carbonized medium-density fiberboard (c-MDF) were studied for electrical, mechanical, and structural properties. X-ray diffraction data suggested that the volume fraction of large turbostratic crystallites increased with carbonization temperature (T). The volume fraction of large carb turbostratic crystallites had a positive correlation with elastic modulus and electrical conductivity. The c-MDF materials were approximately isotropic with respect to elastic modulus and exhibited increasing stiffness with increasing T (up to 4.5 carb GPa). Between 600 and 1400 8C, the electrical resistivity of c-MDF varied by seven orders of magnitude. The electrical resistivity of the hard carbon material in c-MDF 1400 8C was found to be within about an order of magnitude of polycrystalline graphite.

A dielectric resonator technique has been developed for measurements of conductivity and surface resistance of thin metal films deposited on a dielectric substrate. This technique allows for measurements of films having surface resistances that are smaller than 5 without requiring the need to perform measurements of the substrate thickness. The uncertainty of the surface resistance measurements is about 2-3% for both thin films and bulk materials. The accuracy of the conductivity measurements of the thin films is similar to the accuracy of the measurements of their thickness. Several samples have been measured having thicknesses that range from 66 nm to 50 m.

This paper describes a part of the work performed on the determination of the thermophysical properties of alloys in the binary system Li-Pb. The preparation of the eutectic alloy from the pure elements and its characterization using chemical analysis, metallography, thermal and thermal differential analysis is described. Results of the measurements of the following properties are presented: latent heat of fusion, specific heat, density, thermal expansion, thermal and electric conductivity and viscosity. The wetting behaviour of Li(17)Pb(83) against SS 316 is discussed in terms showing the influence of especially of oxygen on the wetting angle in this system.

Ana Silvaa,b, Laura Quintanaa, Matıas Galeanoa & Pablo Errandoneaa aDepartamento de Neurofisiologıa, Instituto de Investigaciones Biológicas Clemente Estable; Unidad Asociada de Facultad de Ciencias, Universidad de la República, Avda. Italia 3318, 11600 ...

Nanostructured polyanilines (PANIs) with a variety of morphologies were synthesized in acidic aqueous solutions with an added ionic liquid, 1-butyl-3-methylimidazolium chloride. The influence of various reaction conditions, i.e., the molar ratio of aniline to ionic liquid and initial aniline concentration, on the morphology and properties of the synthesized PANIs were investigated. The morphologies of the PANIs, as studied by scanning electron microscopy (SEM), range from nanowires to complex three-dimensional structures and were influenced particularly by the molar ratio of aniline to ionic liquid. The chemical structure and molecular-weight characteristics, as determined by Fourier-transform infrared spectroscopy (FTIR), UV-Vis spectroscopy and size-exclusion chromatography (SEC), were not affected by the reaction conditions, indicating that the aniline polymerization mechanism did not change in the presence of the ionic liquid, which acted as a soft template. The conductivities of the prepared PANI samples, as measured by impedance spectroscopy, were of the order of 10 −2 S/cm.

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The use of silver(I)-2-[2-(2-methoxyethoxy)ethoxy]acetate, [AgO 2 C(CH 2 OCH 2 ) 3 H], and its application as an aqueous metal-organic decomposition (MOD) inkjet ink is reported. The chemical and physical properties of the silver carboxylate and the ink formulated thereof are discussed. The ink meets all requirements of piezo driven inkjet printing. The printed features were converted into electrically conducting silver patterns by thermal or photo-thermal treatment. The conversion of [AgO 2 C(CH 2 OCH 2 ) 3 H] to elemental silver follows a two-step decomposition as demonstrated by thermogravimetry-mass spectrometry (TG-MS) measurements. The measured conductivities of the printed features on glass and polyethylene-terephthalate (PET) are 2.7 × 10 7 S m −1 and 1.1 × 10 7 S m −1 , respectively, which correspond to 43% (glass) and 18% (PET) of the bulk silver conductivity.

Conductivities and dielectric constant measurements in water at 25°C have been made on the amphiphilics sodium n-dodecyl sulfate, n-dodecyltrimethylammonium bromide, and chlorpromazine hydrochloride. By using the conductivity/concentration data, critical micelle concentrations (cmc) have been determined by applying the Williams definition and two forms of the Phillips method. This first Phillips form consists of an approximation to Gaussians of the second derivative of the conductivity/concentration data followed by two consecutive integrations. The second form, which is proposed here, consists of the application of a combination of the Runge-Kutta numerical integrations method and the Levenberg-Marquardt leastsquares fitting algorithm. The proposed method permits the determination of the cmc in systems with low aggregation numbers and with slow variations of physical property/concentration curves allowing the determination of the so-called second cmc. A comparative study with results obtained by dielectric constant measurements has been carried out. With this new technique, the cmc's (first and second) are directly obtained as singular points in the dielectric constant/concentration curves, and thus, this technique is an alternative to the determination of cmc's from conductivities.

Conductive fibrous porous materials present strong anisotropy in electrical conductivity. The electrical conductivity of continuous carbon fiber composites is a function of carbon fiber electrical conductivity, fiber direction, preform thickness, fiber volume fraction, length to width ratio and temperature. Along the fiber direction, the conductivity of the composite depends upon the carbon fiber conductivity and on the fiber volume fraction. In the transverse to the fiber direction, the electrical conductivity of the unidirectional (UD) preform depends upon the random fiber-to-fiber contact.

Polyaniline (PANI) has been prepared by the oxidation of aniline with ammonium peroxydisulfate in the 0-4 M phosphoric acid. The maximum conductivity of PANI, 15.5 S cm K1 , was found with PANI prepared in the presence of 1 M phosphoric acid. The mass loss after deprotonation with ammonium hydroxide revealed that relatively large amounts of phosphoric acid were associated with PANI if the polymerization had been carried out at higher acid concentration. This suggests the protonation of both the imine and amine nitrogens in PANI, the increased adsorption of phosphoric acid by PANI, or the presence of polyphosphate counter-ions. The increasing content of phosphoric acid is also reflected in the increase of sample density. FTIR spectra of ammonium salts collected after deprotonation proved that the counter-ions of the sulfate type, resulting from the decomposition of peroxydisulfate, always participated in the protonation of PANI. The proportion of sulfate to phosphate counter-ions was reduced as the concentration of phosphoric acid in the medium increased.

Rotor eddy-current loss is usually significant in high-speed permanent magnet brushless dc (PM BLDC) motors. On the other hand, the rotor is usually protected with a nonmagnetic retaining sleeve. The influence of the conductivity of the retaining sleeve on the rotor eddy-current loss is analyzed in this paper. Furthermore, utility of a conductive copper shield between the sleeve and magnets is demonstrated. Although eddy current is induced in the copper shield, causing additional loss, its magnetic field can smooth the varying field in the rotor and reduce the overall eddy-current loss dramatically. The relationship between the thickness of copper shield and the rotor eddy-current loss is also examined.

This research investigates a capacitive deionization method for salinity reduction in a batch reactor as a new approach for desalination. Reductions of cost and energy compared with conventional desalination methods are the significant advantages of this approach. In this research, experiments were performed with a pair of graphite bipolar electrodes that were coated with a one-gram activated carbon solution. After completing preliminary tests, the impacts of four parameters on electrical conductivity reduction, including (1) the initial concentration of feed solution, (2) the duration of the tests, (3) the applied voltage, and (4) the pH of the solution, were examined. The results show that the maximum efficiency of electrical conductivity reduction in this laboratory-scale reactor is about 55%. Furthermore, the effects of the initial concentration of feed solution are more significant than the other parameters. Thus, using the capacitive deionization method for water desalination with low and moderate salt concentrations (i.e., brackish water) is proposed as an affordable method. Compared with conventional desalination methods, capacitive deionization is not only more efficient but also potentially more environmentally friendly.

The insolubility of single-walled carbon nanotubes (SWNT) in either water or organic solvents has been a limitation for the practical application of this unique material. Recent studies have demonstrated that the suspendability of SWNT can be greatly enhanced by employing appropriate surfactants. Although the efficiency of anionic, cationic, and nonionic surfactants has been demonstrated to different extents, the exact mechanism by which carbon nanotubes and the different surfactants interact is still uncertain. To deepen the understanding of this interfacial phenomenon, we have investigated the effects of chemical modifications of the surface on the extent of nanotube-surfactant interaction. Such changes in the surface chemistry of the SWNT can be achieved by simply varying the pretreatment method, which can be acidic or basic. We have found that intrinsic surface properties such as the PZC (point of zero charge) are greatly affected by the purification method. That is, the electrical charge of the SWNT surface varies with the pH of the surrounding media. However, it has been found that during the adsorption of the anionic surfactant sodium dodecylbenzenesulfonate (NaDDBS) on SWNT Coulombic forces do not play a central role, but are overcome by the hydrophobic interactions between the surfactant tail and the nanotube walls. Only at pH values far from the PZC do the Coulombic forces become important. The hydrophobic forces between the surfactant tail and the nanotube determine the structure of the surfactant-stabilized nanotubes. In such a structure, each nanotube is covered by a monolayer of surfactant molecules in which the heads form a compact outer surface while the tails remain in contact with the nanotube walls. It is important to note that although the final configuration can be described as a cylindrical micelle with a nanotube in the center, the mechanism of formation of this structure does not proceed by incorporation of a nanotube into a micelle, but rather by a two-step adsorption that ends up in the formation of a surfactant monolayer.

In this paper the pulsed eddy current (PEC) response of a range of heat treatable and non-heat treatable aluminium alloys (AA-1050, 2024, 5083 and 7075) to applied stress well below the elastic limit is studied. The effect of prior heat treatment and prior plastic deformation on the stress dependency of the pulsed eddy current response is quantified using the peak value of the PEC difference signal. In certain cases non-linear stress responses are measured. Because it is well known that the effect of stress on conductivity is anisotropic both isotropic (circular) probes and directional (rectangular) probes are compared. It is found that both prior plastic work and heat treatment condition can have a strong effect on the stress coefficients, even changing the sign of the stress dependence. The implications of these effects for the future characterisation of residual stress state by PEC are discussed. 44 0 191 222 563; fax: + 44 0 191 222 8180. E-mail addresses: Maxim.Morozov@ncl.ac.uk (M. Morozov), Philip.Withers@manchester.ac.uk (P.J. Withers). NDT&E International 43 (2010) 493-500

The objective of this study was to assess the physicochemical parameters and waterborne parasites in selected recreational lakes from Malaysia. Samples were collected from seven stations of Recreational Lake A (RL-A) and six stations of Recreational Lake B (RL-B). The samples were processed to detect the presence of Giardia spp. and Cryptosporidium spp. using immunomagnetic separation kit, helminth eggs or ova by bright field microscopy and Acanthamoeba spp. by cultivation in non-nutrient agar. Chemical parameters such as ammonia, chlorine, fluoride, nitrate and nitrite and physical parameters such as dissolved oxygen, electrical conductivity, pH, salinity, temperature and total dissolved solid were also measured. Both lakes were freshwater with salinity ranging from 0.05 to 0.09 ppt. Most stations of these lakes were contaminated with Cryptosporidium spp., Giardia spp., Ascaris spp. and hookworm. Schistosoma spp. was found in RL-B only, while Acanthamoeba spp. was found in all stations. Of all sampling sites, station 5 of RL-B is the most contaminated. Linear regression and correlation analysis revealed that Giardia spp. and Schistosoma spp. showed a significant negative correlation with turbidity (p <0.01). Based on the preliminary data obtained, it is clearly shown that there is a necessity to implement the detection of waterborne parasites and physicochemical analysis in Malaysia. Future work on heavy metals (chromium, copper, mercury and zinc) is recommended to enhance the overall water quality monitoring and to take appropriate safety measures to ensure maintenance of good water standards.

This paper reports the results of an investigation carried out to understand the influence of a fine glass powder on cement hydration. The pozzolanicity of the glass powder and a Class F fly ash for comparison was evaluated using strength activity index over a period of time, and a rapid electrical conductivity based method. Flame emission spectroscopy and electrical conductivity tests were used to quantify the alkali release from glass powder, and gain information on the rate of alkali release. It was found that the glass powder releases only a very small fraction of sodium ions into the solution. It was observed that the glass powder modified pastes show higher non-evaporable water contents than the plain paste and fly ash modified pastes, indicating that glass powder facilitates enhancement in cement hydration. An expression has been developed for the change in non-evaporable water content as a result of enhancement in cement hydration and the hydration of the cement replacement material. The efficiency of any cement replacement material with age in the paste system can be quantified using this parameter. Based on this parameter, a 5% cement replacement with glass powder was found to be effective at the chosen water-to-cementing materials ratio (w/cm), whereas at higher replacement levels, the dilution effect dominates. A model to predict the combined degree of hydration of cement pastes incorporating more than one cementing material is outlined. The measured and predicted combined degrees of hydration agree well.

Polypyrrole-poly ethylene glycol (Ppy-PEG) composites were synthesized by electrochemical method using ρ-toluene sulfonate as a dopant in aqueous medium. Polyethylene glycol was used as the insulating material in order to impart enhanced mechanical properties to the conducting polymer composite films. The composite films were synthesized with various percentages of PEG, and were characterized by FT-IR spectroscopy, conductivity measurement, optical microscopy (OP), X -ray diffraction (XRD) and dynamic mechanical analysis (DMA). The FT-IR result reveals the successful incorporation of PEG into the polypyrrole structure forming Ppy-PEG composite films. The conductivity of the composite films prepared from using 0.20% PEG was found to exhibit the highest conductivity (61.28 Scm -1 ) among all the prepared composite films measured at room temperature. The optical microscopy of Ppy-PEG shows the globular surface morphology. The XRD analysis of Ppy-PEG composite films shows that the composite films are amorphous. The enhanced mechanical properties of the Ppy-PEG composite films are the direct consequence of incorporating PEG in the polypyrrole structure.

We use data from two magnetotelluric profiles, ToSca10 and ToSca'09, over the Scandinavian Mountains to study the crustal structure in southern Norway. The profiles cross the major tectonic structures of the Caledonian orogen as well as the western margin of the Precambrian Baltica. Dimensionality and strike analyses indicate generally 3-D behavior of the data. However, the majority of the used data distinguishes a preferable strike direction, which is supported by the geology of the region. Hence, we employ 2-D inversion and choose to invert the determinant of the impedance tensor to mitigate 3-D effects in the data on our 2-D models. Magnetotelluric data from both profiles are inverted using a damped least squares solution based on a singular value decomposition. We improved the solution by defining the inverse model covariance matrix through gradient or Laplacian smoothing operators. The two-dimensional inversion models of the ToSca'09 and ToSca'10 field data from southern Norway derived from the damped least squares scheme with the Laplacian inverse model covariance matrix are presented. Resistive rocks, extending to the surface, image the autochthonous Southwest Scandinavian Domain and the allochthonous Western Gneiss Region. Near-surface conductors, which are located between the resistive Caledonian nappes and Precambrian basement, delineate highly conductive shallow-sea sediments, so called alum shales. They exhibit a decollement along which the Caledonian nappes were overthrust. A deeper, upper to midcrustal conducting layer in the Southwest Scandinavian Domain may depict the remnants of closed ocean basins formed during the accretions and collisions of various Sveconorwegian terranes. In ToSca'10, the Caledonian nappes, the conducting alum shales and the deeper conductor are terminated in the west by the Faltungsgraben shear complex which represents a crustal scale boundary between the Western Gneiss Region in the west and the Southwest Scandinavian Domain in the east. Tectonophysics j o u r n a l h o m e p a g e : w w w . e l s e v i e r . c o m / l o c a t e / t e c t o Please cite this article as: Cherevatova, M., et al., Crustal structure beneath southern Norway imaged by magnetotellurics, Tectonophysics (2014), http://dx.

This work focuses on the preparation of novel ternary transparent conducting oxide coatings on glass by the sol-gel method. The coatings were deposited by spin-coating from solutions of appropriate metal precursors and heat-treated at different heat-treatment procedures. An increase in electrical conductivity was achieved by a final forming gas treatment. Best electrical and optical properties have been obtained for coatings of crystalline Zn 2 SnO 4 , Zn 3 In 2 O 6 and Zn 5 In 2 O 8 and X-ray amorphous ZnSnO 3 with resistivities in the order of 10 − 2 -10 − 1 Ω cm, an average transmission in the visible of 85% and an average surface roughness of ∼ 1 nm. ZnGa 2 O 4 and GaSbO 4 coatings showed no electrical conductivity. For Zn 2 SnO 4 coatings, a restricted crystallite growth was observed probably due to phase segregation effects. Electrical properties of coatings in the system ZnO-In 2 O 3 were interpreted on the basis of the percolation theory.

The spectral induced-polarization (IP) response of rocks and soils is a complex function of pore solution chemistry, sample microgeometry, and surface chemical properties. We measure the complex conductivity and the time domain IP responses of Berea sandstone as a function of pore fluid ionic strength and pH. Complex conductivity is measured over the frequency range 10 -3 to 106 Hz, and chargeability is computed using a time window of 0.16 to 1.74 s. The field IP parameters: phase, percent frequency effect, and chargeability are functions of both the surface and bulk electrical properties of the sample and are observed to decrease with increasing solution conductivity. Dividing these parameters by the sample resistivity yields normalized IP parameters (quadrature conductivity, metal factor, normalized chargeability) that are proportional to the imaginary component of the complex surface conductivity. Normalized IP parameters increase with ionic strength up to concentrations of 10 -1 M NaC1 and show a reduced response at pH 3, the point of zero charge for quartz-dominated systems. For concentrations > 10 -1MNaC1, the normalized parameters decrease with increasing concentration. This decrease in surface polarization may indicate a decrease in the effective mobility of polarizing charges at high solution concentration. Our data indicate that normalized IP parameters are directly related to the physiochemical parameters that control the surface conductivity responses of rocks and soils. Normalization of IP measurements in environmental investigations should increase the effectiveness of IP surveys, especially in high-conductivity environments. The IP response of rocks and soils is controlled by electrochemical polarization mechanisms that are a function of the surface chemical and the microgeometrical properties of the sample. In earth materials containing water, ions from the saturating solution are attracted to the mineral surface, which usually has negative net surface chargeß These ions form an electric double layer (EDL) that consists of a fixed layer of charge that is chemically adsorbed to the grain surface and a diffuse layer of charge that extends into the pore space. When an electric field is applied to the material, the ions in the EDL migrate tangentially to the grain surfaces and the grains become polarized. The polarization of the EDL leads to a frequency-dependent complex surface conductivityß This surface conductivity is a function of the surface charge density, the surface ionic mobility, and the grain size distribution [Lima and Sharma, 1992' Lesmes and Morgan, 2001]. The complex surface conductivity is usually assumed to add in parallel with the bulk electrical properties of the sample. Commonly measured field IP parameters, such as phase, percent frequency effect, and chargeability, are dependent upon both the surface and bulk electrical properties of the material [Marshall and Madden, 1959; Collett and Katsube, 1973; Van Voorhis e! al., 1973; Vinegar and Waxman, 1984]. Dividing the field IP parameters by the formation resistivity, or multiplication by the formation conductivity, yields the r,,• .... ;*"• normalized TD parameters l%Jll%J ¾¾ Ill s metal factor, and a normalized chargeability called "specific capacity" [Marshall and Madden, 1959; Keller, 1959]. These normalized IP parameters are more sensitive to the surface chemical properties of the sample and therefore are more 4079 1984]. LESMES AND FRYE: PORE FLUID CHEMISTRY DEPENDENCE OF IP 4081 Technol., 6, 44-57, 1954.

Thermally activated ("thermal") batteries are primary batteries that use molten salts as electrolytes and employ an internal pyrotechnic (heat) source to bring the battery stack to operating temperatures. They are primarily used for military applications, such as missiles and ordnance, and in nuclear weapons. This paper discusses the development history and presents a general overview of this technology.

Soil salinisation is very often due to excessive irrigation. However, irrigation is absolutely essential for obtaining reliable crop yields, particularly under predicted global warming conditions. A simple methodology for assessing the salinisation risk for any water management situation and under predicted global warming conditions is presented. The methodology is illustrated by the assessment of irrigation effects on soil salinity at San Antonio del Sur Valley, in the southeast of Cuba. Irrigation from a new dam will support agriculture in the Valley, but at the same time soil salinity is expected to increase. Soil electrical conductivity at several depths and topographical altitudes were used to create raster layers in a Geographic Information System (GIS), thus, determining the border of the saline-affected zones by a GIS analysis. Water-table depth at the border of the saline zones was assumed to be 2 m. The physically based SWAP model was used to predict future water-table depths after irrigation begins and under global warming conditions. Future temperature and precipitation daily values were calculated from a linear increase/decrease of the daily values corresponding to a typical year, according to a global-change forecast for the zone. Soil hydraulic properties were estimated from pedotransfer function and published soil data. Simulated results predict a fast water-table raise of 1 m, due to the increase of irrigation water. Borders of the new saline zones under these conditions (i.e. the places where the water-table is at a 2 m depth) were calculated using a digital terrain model, assuming that the water-table rose 1 m over the whole valley. According to the simulation results, the original saline zones of the valley will be enlarged from 31.4 to 96.8 ha 15 years after the scheduled start of irrigation. The methodology could be used by farmers and decision-makers to select the most suitable water management solution considering both economical and environmental criteria. # .cu (A. Utset).

The variations of thermal conductivity with temperature for Al-[x] wt.% Cu, x = 3, 6, 15 and 24 alloys were measured by using a radial heat flow apparatus. The variations of electrical conductivity of solid phases versus temperature for the same alloys were determined from the Wiedemann-Franz and Smith-Palmer equations by using the measured values of thermal conductivity. From the graphs of thermal and electrical conductivity versus temperature, the thermal conductivity of the solid phases at their melting temperatures, and the thermal temperature and the electrical coefficients for the same alloys were obtained. Dependency of the thermal and electrical conductivity on the composition of Cu in the Al based AlÀCu alloys were also investigated. According to present experimental results, the thermal and electrical conductivity of Al-[x] wt.% Cu, x = 3, 6, 15 and 24 alloys linearly decrease with increasing the temperature and composition of Cu. The enthalpy of fusion and the specific heat change during the transformation for the same alloys were determined from cooling trace during the transformation from eutectic liquid to eutectic solid by means of differential scanning calorimeter (DSC).

Carbon fiber/epoxy composite specimens are manufactured using liquid resin infusion and incorporate a copper wire mesh on the outer layer for lightning strike protection. The specimens are then painted in order to be representative of an aircraft skin. The specimens are subjected to a scarf repair, which removes a portion of the wire mesh and of the carbon fiber substrate. The bonded repair is performed to re-establish the structural and electrical integrity of the laminate. Purpose of the study is to evaluate the effect of repair procedure on the structural performance of the carbon/epoxy specimens following a lightning strike, and in particular it is aimed at comparing the two extreme cases where full electrical conductivity is re-established, and where the electrical conductivity is interrupted. To do so, the copper wire mesh is re-applied during the repair following two scenarios. The first, denoted as ''good'' repair, involves overlapping part of the repair mesh with the parent mesh surrounding the repair area, while the second, referred to as ''poor'' repair, involves applying a repair mesh that is shorter than the parent mesh, thereby leaving a gap in the electrical path. The repaired specimens are then subjected to simulated lightning strike at the location of the repair. The damage resistance characteristics of the repaired specimens are compared to the benchmark values of unprotected specimens (i.e. without copper mesh) and protected pristine specimens (i.e. without repair). Residual strength testing using four-point bend flexure is used to assess the damage tolerance behavior of the specimens. Results show that a ''good'' repair performs as well as the pristine protected specimen, while a ''poor'' repair performs equally or worse than a fully unprotected specimen.