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Nickel(II), manganese(III), and magnesium(II) porphyrazines are synthesized and investigated as active electrode components of polyvinyl chloride plasticized membranes for ion-selective electrodes (ISE). The potentiometric response of membranes based on metalloporphyrazines doped with 1, 3-dihexadecylimidazolium chloride (ionic additive) relative to benzylpenicillin and iodide anions is studied. It is found that the introduction of the ionic additive significantly improves the electrochemical characteristics of the ISE: the slope of the electrode function in benzylpenicillinate solutions is (58 ± 7) mV/dec and [c.sub.min] = 7 x [10.sup.-5] M, and in iodide solutions, (55 ± 2) mV/dec and [c.sub.min] = 6 x [10.sup.-6] M. It is shown that the ISE based on manganese(III) porphyrazine with an ionic additive can be used to determine iodide in Iodinol preparation. Keywords: metalloporphyrazines, ion-selective electrodes, dihydrogen phosphate, benzylpenicillin, iodide DOI: 10.1134/S1061934815010177, In recent decades, metal-complex receptors have been increasingly used in ion-selective electrodes for the direct potentiometric determination of various ions. The development of ISE for anions is a challenging task [...]

The preparation and characterization of Pt nanoelectrodes in the range of 1 to 3 nm in radii are reported. APt microwire is sealed into a bilayer quartz capillary and pulled into an ultrasharp Pt nanowire sealed in a silica tip using a laser-assisted pulling process. The ultrasharp tip is then sealed into a piece of glass tubing, which is manually polished to expose the Pt. Transmission electron microscopy and steady-state voltammetry are utilized to characterize the nanoelectrodes. The results show that the minimum size of the Pt nanoelectrode is determined by the size of the Pt microwire and parameters used in the pulling process. The heterogeneous electron transfer rate constant for the oxidation of ferrocene, ferrocenemethanol, and potassium hexachloroiridate (III) are determined from steady-state voltammetry using the method of Mirkin and Bard and are found to be [k.sup.o] = 7.6 [+ or -] 3.4 cm/s and = 0.85 [+ or -] 0.06 for ferrocene, [k.sup.o] = 7.4 [+ or -] 6.9 cm/s and = 0.78 [+ or -] 0.16 for ferrocenemethanol, and [k.sup.o] = 6.0 [+ or -] 4.2 cm/s and [alpha] = 0.72 [+ or -] 0.15 for Ir[[Cl.sub.6.sup.3-].

An improvement in dielectric strength is required in vacuum circuit breakers (VCBs) intended for use in higher voltage systems. In order to develop higher voltage VCBs, it is important to improve the dielectric strength in a vacuum based on consideration of the vacuum breakdown mechanism. Particularly for gaps longer than 10 mm, little is known about the breakdown mechanisms and their quantitative analyses in a vacuum. This paper discusses the breakdown conditioning characteristics of long gap electrodes, under a non-uniform electric field in a vacuum. We treat gap lengths of up to 50 mm in this paper. The conditioning characteristics are investigated under impulse voltage applications. A negative standard lightning impulse voltage was applied to rod-plane electrodes made of Cu-Cr and SUS304 for different tip radii and gap distances until the conditioning effect was completed. We observed illumination spots on electrodes at each breakdown during the conditioning process and calculated the corresponding breakdown field strengths. Experimental results revealed that the tendency of breakdowns associated with long gaps is different from that for the short gaps. As a result, we clarified that the breakdown field strengths are nearly constant at 110-120 kV/mm at the distances longer than 10 mm, and the breakdown field strength is at its maximum when the gap distance is about 5 mm. Index Terms--Breakdown conditioning, non-uniform electric field, long gap, lightning impulse voltage.

This paper presents a new methodology for the adjustment of the preheating process and steady-state operation of electronic ballasts intended for hot-cathode fluorescent lamps. The classical series-resonant parallel-loaded half-bridge inverter is the power stage analyzed in this paper. In addition, the preheating process is based on the imposition of a constant rms current through the electrodes, in order to provide a proper value of the [R.sub.h]/[R.sub.c] ratio before the lamp start. According to the proposed methodology, it is possible to set suitable operating points for the electronic ballast, considering optimal conditions for the lamps electrodes. Therefore, the proposed methodology for setting the preheating and steady-state operation is a complete platform to the design of electronic ballasts for hot-cathode fluorescent lamps. Index Terms--Electrodes filaments, electronic ballasts, fluorescent lamp model, preheating process, [R.sub.h]/[R.sub.c] ratio.

A two-band model of free electrons in ferromagnetic electrodes is used to study the magnetoresistance of low and high barrier magnetic tunnel junctions (MTJs). It is demonstrated that tunneling magnetoresistance (TMR) and the electron current density through MTJs depend significantly on the dielectric constant of the MgO insulator and the electron current density through low barrier MTJs can be high enough to change the magnetization of a ferromagnetic electrode.

The thickness-shear vibrations of rotated Y-cut quartz places with electrodes of different thickness are analyzed. It is seen that different electrodes showing the possibility of an alternative of contoured or mesa resonators can achieve strong energy trapping.

This paper is intended to present a comprehensive and objective approach to the behavior of grounding electrodes when subjected to lightning currents. Index Terms--Grounding, lightning currents, transient grounding behavior.

The effect of the three-electrode voltage distribution on the microdischarge characteristics of an ac-PDP with a long discharge path (400 [micro]m) is investigated. It is found that the auxiliary pulse applied to the address electrode, which participates in the trigger discharge, plays a key role in lowering the sustain voltage in the long discharge path by both providing the priming particles to generate the main discharge and accumulating more wall charges with the proper polarity to help the next discharge. In particular, the amplitude and width of the auxiliary pulse are very important parameters in a large sustain gap structure, as they are related to both the electron channeling that bridges the long discharge path and the accumulation of wall charges on the sustain electrodes. Thus, the effect of the width and amplitude of the auxiliary short pulse on the discharge characteristics, such as a low sustain voltage, the luminance, and luminous efficiency, are extensively investigated. As a result, the existence of a proper width and amplitude for the auxiliary pulse to lower the sustain voltage is observed, thereby also improving the luminous efficiency. Index Terms--Auxiliary short pulse applied to address electrode, large sustain gap, long discharge path, voltage distribution among three electrodes.

Current-voltage characteristics of array electrodes in laboratory plasma have been studied in association with the interaction of high-voltage solar array with the ambient space plasma. An electrode or an array of electrodes distributed on a dielectric material were used to simulate the interconnectors of the solar-array panel in space environment. It has been found that the charging effect and secondary electrons of the dielectric material play an important role in the collection of the electrode current. In the array configuration, the current of each electrode was generally suppressed, as compared with that of single electrode, but a rapid enhancement of the electrode current was observed when the spacing of the electrodes was less than a critical value. These results indicate a possibility that the high-voltage plasma interaction can be suppressed if we select proper dielectric material for the panel and proper distribution of the solar-array voltage. Index Terms--High-voltage solar array, plasma interactions, spacecraft charging.

We report on an R&D program targeted to produce large area glass resistive plate chamber (RPC) detectors. The aim of this work has been to exploit as much as possible glass industry standard techniques. One of the most important steps we have introduced to reach the goal of fully automated production of large area detectors has been the use of screen silk printing technique for the resistive electrodes. A substantial number of prototypes detector have been produced: [approximately equal to]100 [m.sup.2]. The detector's efficiency as a function of the local particle rate has been tested at the DAFNE Beam Test Facility with 500 MeV electrons. Results concerning long term stability tests, presently going on by means of two cosmic ray telescopes in two different laboratories, will also be presented. Index Terms--Ageing, glass, rate capability, resistive plate chamber (RPC).

The three-dimensional flow interaction between the primary flow and the secondary flow (often called an electric wind or ionic wind) for tuft/point corona in the wire-duct type electrostatic precipitators (ESPs) has been investigated in the past. This study was further extended to incorporate the alternately oriented point corona on the wire-plate type electrodes, which are commonly used for the industrial ESPs. The secondary flow distribution without gas flow consists of a pair of long-elliptic and circulatory cells between spikes points along the wire. However, the flow rotation between spiked points is the same direction, which is opposite to that of the point corona electrode. The flow interaction is described using dimensionless number, [N.sub.EHD], which is the ratio of the ionic wind velocity to the primary flow velocity. When the primary flow exists, a pair of long-elliptic spiral flows is formed in the direction of the gas flow between ground plates. When the relative distance between the spike point spacing and the wire-to-plate spacing (or the ratio of [S.sub.z]/d) is greater than 0.17, the organized long-elliptic spiral flow is formed. When [S.sub.z]/d is less than 0.1, the organized spiral flow is diminished, resulting in turbulence. Index Terms--Electrohydrodynamics, ionic wind, flow interaction, spiked-electrode, [N.sub.EHD] number, electrostatic precipitator

The IEC 60093 Standard, prepared by the International Electrotechnical Commission in 1980, sets up methods of measurements, determination and calculation of volume and surface resistivities of solid dielectrics. The document contains some editorial mistakes as well as content-related inaccuracies that require revisions. Besides corrections of obvious editorial mistakes it is suggested to introduce some content-related improvements. The most important remarks given in the paper are associated with the following problems: 1) shunting of the current meter by the resistance between guarding and guarded electrodes; 2) significant influence of the electrodes made of conducting rubber on volume resistivity measurement results; 3) errors associated with application of simplified expressions for resistivitiy calculations (volume resistivity for tubular samples, surface resistivity for samples with circular electrodes); 4) increase of the effective surface of the measuring electrode (margin width determination and consideration). Finally, proposals of alterations of particular clauses of the standard, supplemented with appropriate justifications, were given in the paper. Index Terms--Dielectric materials, resistivity measurement, electrodes, standardization.

Cathode initiation of vacuum breakdown in dc and pulse modes is considered. New criteria and methods for evaluating the cathode initiation mechanism are proposed. They are based on consideration of relative changes in cathode surface state and electric strength. The elaborated criteria and methods have been verified with experiments results using dc and pulse modes of high-voltage treatment of electrodes. Accuracy of the proposed methods exceeds known methods precision. It is shown that optimum modes of pulsed conditioning can be used for definition of top boundary of cathode initiation mechanism applicability in dc mode. Index Terms--Vacuum insulation, vacuum breakdown, surface treatment, insulation testing, quality control.

We describe an electrochemical cell containing a single faradic electrode (a Pt ultramicroelectrode) and a blocked (polarized) electrode (Si with an insulating Si[O.sub.2] film) that served as a capacitive counter electrode. When a bias was applied between the two electrodes, a current was observed from a faradic process at Pt and a capacitive current at the blocking electrode. A steady charging current was obtained when the solution was moved along the insulator to continuously contact fresh surface (emersing a layer of charged ions and electronic countercharge into the gas phase). Electrogenerated chemiluminescence was clearly observed from a system containing Ru[(bpy).sub.3.sup.2+] in this kind of cell under pulsed excitiation, demonstrating that faradaic reactions can be carried out in an electrochemical cell without generation of any products at a counter electrode. The use of such a system for coulometric addition of desired species in nanosystems and in synthesis is suggested.