Evaluation of electrode-sample contact impedance under different curing humidity conditions during measurement of AC impedance of cement-based materials

In this study, a simple method was proposed to calculate electrode-sample contact impedance in the cases of two-point and four-point measurements. The results indicated that when using the saturated calcium hydroxide solution (SCH) as conductive medium, the contact impedance in the four-point measurement is negligible for the impedance range of cement-based materials. The SCH can be used as a reference for correction of the contact impedance. A reasonable combination of curing humidity and different conductive media is recommended for the two-point measurement, which is suitable for testing the ACIS of cement-based materials. In a case of contact impedance not being precisely known, it is highly recommended that a four-point measurement with two different ratios of the length of the sample and the center spacing of the voltage electrodes (L/a) should be conducted to evaluate the effect of the contact impedance following the procedure proposed in this study.

Ultra-fast conductive media for RNA electrophoretic mobility shift assays

The use of RNA electrophoretic mobility shift assays (REMSAs) for analysis of RNA–protein interactions have been limited to lengthy assay time and qualitative assessment. To vastly improve assay efficiency, feasibility and quality of data procured from REMSAs, we combine here some of the best-known labeling and electrophoretic techniques. Nucleic acid fragments are end-labeled with fluorescent tags, as opposed to the radioactive or biotin tags. The fluorescent probes may be detected directly from the electrophoresis gel, eliminating the need for cumbersome membrane transfer and immunoblotting. Modifying the REMSA protocol to include low-molarity, lithium borate conductive media and near-infrared-labeled probes allows for a reduction assay time, quantitative comparison between experimental conditions and crisp band resolution (i.e., optimized results).

Wireless Technology of Electric Power Transmission Using Non-Metal Conductive Media

Over two million kilometers of power grids in Russia exist. They have to be replaced in the coming 15 years. However, nowadays we witness and participate in the development of advanced technologies. New wireless resonant electric-power systems for different power consumers are considered including stationary single-conductor transmission lines and single-trolley and noncontact high-frequency electric transport, using non-metal conductive media. The trends of the future development and application of wireless resonant systems for electric power transmission are described. In the future, electrified mobile robots with external wireless electric power supplies will allow the organization of agricultural production with full automation of technological processes. The chapter describes the method and means for electric power transmission without metal wires. In this case, several components of conventional transmission lines, such as metal wires, insulators, and cables, are excluded, which results in considerable reduction in the equipment cost.

Application of the Shifted Frequency Internal Equivalence to Two Dimensional Lossy Objects

Performance of a new method, Shifted Frequency Internal Equivalence (SFIE) is studied in the analysis of scattering from two dimensional lossy objects. This method finds the solution of a wideband scattering problem faster than classical approaches.By introducing conductivity, loss shows itself as imaginary electrical permittivity. Changing conductivity also changes the distribution of electromagnetic waves and modifies RCS plots. In this study homogeneous and inhomogeneous conductive media are investigated to widen the usage of SFIE method. By increasing conductivity skin effect phenomenon is observed, electrical dimensions are decreased and RCS plots are flattened as expected.Numerical results obtained by SFIE are compared to the ones obtained by Method of Moments and the differences are shown.