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Can Electrical Conductivity Predict Seed Germination of Three Pinus Species?

leachate conduc - tivity measurements. Canadian Journal of Forest Research 23(5): 864-870. SǾRENSEN, A., E. B. LAURIDSEN and K. THOMSEN (1996): Electrical conductivity test. Technical Note No. 45. Danida Forest Seed Centre, Denmark. YOUNG, J. A and CH. G. YOUNG (1992): Seeds of Woody Plants in North America. Dioscorides Press, Portland, Oregon. ZHAO, G. and T. ZHONG (2012): Improving the assessment method of seed vigor in Cunninghamia lanceolata and Pinus massoniana based on oxygen sensing technology. Journal of Forestry

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Effects of Extremity Elevation and Health Factors On Soft Tissue Electrical Conductivity

References Heller, J., Feldkamp, J.R. (2009). Auto-tuned induction coil conductivity sensor for in-vivo human tissue measurements. Meas. Sci. Rev. , 9, No. 6, 162-168. Holder, D.S. (ed.) (2004). Electrical Impedance Tomography: Methods, History and Applications. Institute of Physics. Haemmerich, D., Staelin, S.T., Tsai, J.Z. (2003). In vivo electrical conductivity of hepatic tumors. Physiol. Meas. , 24, 251-260. Stinstra, J.G., Shome, S., Hopenfeld, B

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Continuous field soil moisture content mapping by means of apparent electrical conductivity (ECa) measurement

References Anderson, T.W., Darling, D.A., 1954. A test of goodness of fit. Journal of the American Statistical Association, 49, 765-769. Baráth, C., Ittzés, A., Ugrósdy, G., 1996. Biometry. (Biometria.) Mezőgazda Kiadó, Budapest. (In Hungarian.) Brevik, E.C., Fenton, T.E., 2002. The relative influence of soil water, clay, temperature, and carbonate minerals on soil electrical conductivity readings taken with an EM-38 along a Mollisol catena in central Iowa. Soil Survey Horizons, 43, 9

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Electrical conductivity of low-temperature sodium-potassium cryolite melts

Abstract

Electrical conductivity of NaF-KF-AlF3 melts with different ratios of sodium fluoride and potassium fluoride was measured using a pyrolytic boron nitride tube-type cell with constant distance of electrodes. Molar cryolite ratios MR = (n(NaF) + n(KF))/n(AlF3) varied from 1.5 to 1.2 (with a step 0.1) in the temperature range of (675—900) °C. AC-techniques with a sine wave signal with small amplitude in the high frequency range were applied. Electrolyte resistance was obtained from nonlinear regression analysis according to equivalent circuit. Concentration and temperature dependency of electrical conductivity was described and defined. Experimental data were compared with literary sources and regression equations.

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The electrical conductivity of jet fuels F–34 and F–35 (JET A–1) in distribution

Abstract

The paper presents a changeability of electrical conductivity of jet fuels in distribution. Author described the methods used to prevent the formation of the dangers of static electricity. Research was carried out on two basic fuels used worldwide to power engines in civil (Jet A – 1) and military aircrafts (F – 34), during real fuel supplies in aviation military unit. Results of influence of temperature on the electrical conductivity of jet fuel are presented.

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The relation of the seismicity in the eastern part of the Ukrainian Carpathians and the distribution of electrical conductivity in the Earth’s crust

Abstract

We present results of a study of the peculiarities of the seismicity and electrical conductivity distribution beneath the Ukrainian Eastern Carpathians. Based on the analysis of seismic data for the years 1999–2016, specific zones of concentration of earthquake sources related to the principal fault systems and their intersections have been distinguished. This paper covers two zones, one linked to the contact of the Outer Carpathians and the Carpathian Foredeep and another one linked to the fault system transverse to the Carpathians strike. Both belts of earthquake sources concentration correlate well with the geoelectric models of the studied area obtained as a result of 2D and quasi-3D inversion. Most of the seismic events occur at the intersection of the mentioned seismic zones, at shallower depths, than the main conductive structures appear, concentrated at their marginal parts. The interrelation of both phenomena suggests their common explanation by processes occurring in active fault systems: fracturing, shear deformation, migration of highly mineralized fluids, high porous pressure, accumulation and release of tectonic stress.

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Electrical conductivity of Pd47Ni47Si6 amorphous membrane while hydrogen permeation

Abstract

Hydrogen diffusion through an amorphous membrane causes local disorders in the structure which can be detected through the measurement of changes of the electrical conductivity. Detecting these changes and comparing them directly with the amount of the permeated hydrogen provides information on the efficiency of separation, which can be used in hydrogen sensor and analyzer technology. This paper presents the results of electrical resistivity measurement of Pd47Ni47Si6 alloy amorphous membrane while hydrogen permeation flux was being changed along with the temperature. It was found that hydrogen changes the nature of the resistivity and the temperature coefficient of resistivity is negative, however, starting from the temperature of 365 K, its value becomes smaller. In order to explain this phenomenon thorough and detailed measurements of phase transitions were made with the use of differential scanning calorimetry and X-ray diffractometry. On the basis of the research an attempt was made to explain the recorded changes of electrical conductivity.

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Electrical conductivity of molten fluoride-oxide melts with high addition of aluminium fluoride

Abstract

Electrical conductivity of NaF-AlF3 melts with an addition of 2 wt % Al2O3 and/or 5 wt % CaF2 was measured using a pyrolytic boron nitride tube-type cell with a constant distance of electrodes. The molar cryolite ratios MR = n(NaF)/n(AlF3) were 1.8 and 1.6, and the temperature was varied from 865 °C to 1005 °C. Ac-techniques with a sine wave signal with small amplitude in the high frequency range were applied. Electrolyte resistance was obtained from nonlinear regression analysis according to equivalent circuit. Experimental data were used to describe the dependence of the electrical conductivity in fluoride melts with lower temperature on the amount of various additions and temperature.

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Synthesis, morphology, electrical conductivity and electrochemical properties of α-Ni(OH)2 and its composites with carbon

Abstract

A simple and effective hydrothermal synthesis of spherical α-Ni(OH)2 particles and α-Ni(OH)2/carbon composites was proposed. The mechanism of ultrafine α-Ni(OH)2 phase forming and correlations between synthesis conditions, morphology, electrical conductivity were analyzed. It was found that carbon nanoparticles form an electric conductive cover on nickel hydroxide microparticles during synthesis which increases overall electronic conductivity of the composite material. α-Ni(OH)2 and α-Ni(OH)2/C samples were tested as electrodes for hybrid supercapacitors. It was found that carbon coverings stabilize α-Ni(OH)2 phase in the alkaline medium. The comparison of the influence of laser irradiation and ultrasonic treatment on the electrochemical performance of the obtained materials was made.

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Synthesis, effect of γ-ray and electrical conductivity of uranium doped nano LiMn2O4 spinels for applications as positive electrodes in Li-ion rechargeable batteries

Abstract

LiMn2O4 is an attractive candidate cathode material for Li-ion rechargeable batteries, but it suffers from severe capacity fading, especially at higher temperature (55 °C) during charging/discharging processes. Recently, many attempts have been made to synthesize modified LiMn2O4. In this work, a new study on the synthesis of pure and U4+-doped nano lithium manganese oxide [LiMn2−x UxO4, (x = 0:00, 0.01, 0.03)] via solid-state method was introduced. The synthesized LiMn1:97U0:03O4 was irradiated by γ-radiation (10 and 30 kGy). The green samples and the resulting spinel products were characterized using thermogravimetric and differential thermal analysis (TG/DTA), X-ray diffraction (XRD), infrared (IR), and scanning electron microscopy (SEM) measurements. XRD and SEM studies revealed nano-sized particles in all prepared samples. Direct-current (DC) electrical conductivity measurements indicated that these samples are semiconductors and the activation energies decrease with increasing rare-earth U4+ content and γ-irradiation. ΔEa equals to 0.304 eV for LiMn1:99U0:01O4, ΔEa is 0.282 eV for LiMn1:97U0:03O4 and decreases to ΔEa = 0:262 eV for γ-irradiated LiMn1:97U0:03O4 nano spinel. The data obtained for the investigated samples increase their attractiveness in modern electronic technology.

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