Влияние ионного состава раствора и температуры на аномальную электропроводность тонких слоев электролита при электролизе воды

Досліджено вплив іонного составу та температури на аномальну електропровідність поверхневого шару електроліту при електролізі води. Було показано, що підвищення температури руйнує поверхневу структуру воді і зменшує аномальну електропровідність. Введення неорганічних іонів до розчину також зменшує аномальну електропровідність розчина в порівнянні з дистильованою водою. Існує кореляція між аномальній електропровідністю та поверхневим натягом розчинив.Determination of temperature and ion composition on anomalous electrolytic conductivity of gas-liquid interface was investigated. It was show, increase of temperature destroy surface structure of water and decrease anomalous electrolytic conductivity. Inorganic ions decrease anomalous electrolytic conductivity too. It is correlation between electrolytic conductivity and surface tension

Improved separators for silver oxide-zinc and silver oxide-cadmium cells for spacecraft application Third quarterly progress report, 10 May - 9 Aug. 1965

Improved separators for silver oxide-zinc and silver oxide-cadmium cells - flexibility and electrolytic conductivity in modified methyl cellulose polyacid film

Alkaline electrochemical cells and method of making

Equilibrated cellulose ether membranes of increased electrolytic conductivity for use as separators in concentrated alkaline electrochemical cells are investigated. The method of making such membranes by equilibration to the degree desired in an aqueous alkali solution mantained at a temperature below about 10 C is described

Metrological Traceability Concept for Electrolytic Conductivity and pH

The metrological traceability concept links measurement results by a chain of calibrations to the quantity values of primary standards, which are realised by primary measurement procedures. These procedures undergo periodical international comparison measurements, in order to guarantee worldwide comparability of measurement results. In this article we demonstrate how the metrological traceability concept applies to electrolytic conductivity and pH measurements. Furthermore we will outline promising activities in current metrological research to extend traceability of electrolytic conductivity measurements down to the low ?S cm?1 level

Separator for alkaline electric batteries and method of making

Battery separator membranes of high electrolytic conductivity comprising a cellulose ether and a compatible metallic salt of water soluble aliphatic acids and their hydroxy derivatives are described. It was found that methyl cellulose can be modified by another class of materials, nonpolymeric in nature, to form battery separator membranes of low electrolytic resistance but which have the flexibility of membranes made of unmodified methyl cellulose, and which in many cases enhance flexibility over membranes made with unmodified methyl cellulose. Separator membranes for electrochemical cells comprising a cellulose ether and a modified selected from the group consisting of metallic salts of water soluble alphatic acids and their hydroxy derivatives and to electrochemical cells utilizing said membranes are described

Zinc-rich paint coatings containing either ionic surfactant-modified or functionalized multi-walled carbon nanotube-supported polypyrrole utilized to protect cold-rolled steel against corrosion

The intense anodic action of sacrificial zinc pigments ensured viable galvanic function of the highly porous liquid zinc-rich paints (ZRPs) result in deteriorated long-term corrosion resistance often accompanied by cathodic delamination phenomena. In our approach, such a efficacy problem related to the corrosion preventive function of ZRPs is addressed by the application of intimately structured anodic inhibitor particles composed of nano-size alumina and either polyelectrolyte-modified or chemically functionalized multi-walled carbon nanotubes (MWCNT) supported polypyrrole (PPy) in one specific zinc-rich hybrid paint formulation providing balanced active–passive protective functionality. High dispersity of the nanotube-free PPy-deposited inhibitor particles (PDIPs) with uneven polymer distribution on the alumina carrier was confirmed by transmission electron microscopy (TEM) observations. Furthermore, the MWCNT-embedded PDIPs indicated almost complete surface coverage of the alumina-nanotube carriers by PPy with decreased microstructure dispersity which is attributed to the effect of double-flocculants type co-deposition of the oppositely charged polymers causing coalescence of the modified particles. Depending on the amount of the nanotubes and their proportion to the quantities of the deposited PPy and polyelectrolyte as well as the concentration of the surfactant, varied micron-scale association of the PDIPs in the suspensions of dissolved alkyd matrix was disclosed by rheology characterization carried out at particular solid contents similar to hybrid paint formulation. The evenly distributed but less densely packed nano-structure of PPy was evidenced on the polyelectrolyte-modified nanotubes by Fourier-transform infrared (FTIR) spectroscopy whereas more compact polymer film formation was confirmed on the surface of functionalized nanotubes. According to the greater electrical conductivity, enhanced electroactivity and reversibility of the nanotube-embedded PDIPs were indicated over the nanotube-free particles by cyclic voltammetry, depending on the type and the amount of the nanotubes and their modification. Protection function of the hybrid paint coatings (formulated with spherical zinc pigment at 70 wt.%) was investigated by immersion and salt-spray chamber tests over 254 and 142 day periods, respectively. Firm barrier nature of the nanotube-embedded PDIP contained hybrids was proved by electrochemical impedance spectroscopy (EIS) and radio-frequency glow-discharge optical-emission-spectroscopy (RF-GD-OES). Furthermore, due to the increased conductivity of the nanotube-embedded PDIPs cemented in epoxy primers optimally at 0.4 and 0.6 wt.%, altered corrosion preventive behaviour of the hybrid coatings was indicated by the positively polarized open-circuit potentials (OCPs) and the X-ray photoelectron spectroscopy (XPS) detected lower relative quantities of the interfacially accumulated zinc corrosion products, moderate oxidative degradation of the epoxy vehicle. Decreasing oxidative conversion of iron at the surface was indicated by XPS found to correlate with the increasing intensity of zinc corrosion and decreasing oxidative degradation of the epoxy binder, according to the higher nanotube contents of hybrid coatings. In addition, inhibited zinc corrosion caused low rate of oxidative degradation of epoxy, allowing increased durability of coating adhesion and cohesion thereby ensuring reliable protection by zinc-rich compositions. As a conclusion, modified or functionalized MWCNTs acting as unexchangeable doping agents promote enhanced reversibility and increased conductivity of PPy, forming nano-size inhibitor particles with advanced features. Thus, such inhibitor nano-particles in zinc-rich hybrid compositions afford improved barrier and high efficiency galvanic–cathodic corrosion preventive function, exceeding long-term protection capability of the conventional ZRPs

Investigating the impact of microbial interactions with geologic media on geophysical properties

The goals of this study were to investigate the effect of: (1) microbial metabolic byproducts, microbial growth, and biofilm formation on the low frequency electrical properties of porous media, (2) biofilm formation on acoustic wave properties, and (3) the natural electrical (self-potential) signatures associated with an in-situ biological permeable reactive barrier (PRB). The results suggest: (1) increases in electrolytic conductivity are consistent with increased concentrations of organic acids and biosurfactants; (2) mineral weathering promoted by organic acids causes increases in electrolytic conductivity, concomitant with increases in major cation concentrations; (3) interfacial conductivity generally parallels microbial cell concentrations and biofilm formation; (4) variations in microbial growth and biofilms causes spatiotemporal heterogeneity in the elastic properties of porous media; (5) SP signatures associated with the injection of groundwater into an in-situ biological PRB are dominated by diffusion potentials induced by the injections. The results suggest that electrolytic conductivity may be useful as an indicator of metabolism, while interfacial conductivity may be used as proxy indicator for microbial growth and biofilm formation in porous media. In addition, acoustic measurements may provide diagnostic spatiotemporal data for the validation of bioclogging models/simulations. Collectively, this study provides further evidence that geophysical measurements are sensitive to microbial-induced changes to geologic media, and may be useful for the detection and monitoring of subsurface microbial growth, activity, and distribution such as in microbial enhanced oil recovery, assessing biofilm barriers used for contaminant remediation, or as sealants for reservoirs in CO₂ sequestration studies --Abstract, page iv

Condutividade elétrica de complexos organominerais sintéticos

The mechanism of the formation of organomineral complexes in soils is very complex and still little known. Examination of the complexes in unaltered form, as isolated from the soil, is very difficult due to the dispersing effect of all extraction agents which break the complexes up, destroying their natural properties. It is much easier to perform most of the tests on preparations of organomineral complexes obtained under laboratory conditions. This paper is concerned with model research on the formation of synthetic complexes of humic acids with minerals: Na-montmorillonite, mica, kaolinite at various pH values (3-7) and in the presence of aluminum ions. The aim of the research was to develop an optimum reaction of suspension for the synthesis of organomineral complexes, to study the role of aluminum ions, and to attempt to determine the degree of their complexity on the basis of the electrolytic conductivity (EC). An important influence of the suspension pH value on the value of EC was observed. The greatest correlation was found in the organomineral preparations with kaolinite and with aluminum (r = 0.93***). Generally, it can be stated that the degree of reaction of humic acids with minerals depended most of all on the type of mineral, on the pH value, and on the presence of aluminum.O mecanismo de formação de complexos organominerais no solo é muito complexo e ainda pouco conhecido. O exame destes complexos em sua forma inalterada, quando isolados do solo, é muito difícil devido ao efeito dispersivo de todos agentes de extração que quebram estes complexos, destruindo suas propriedades naturais. É muito mais fácil executar a maioria dos testes em preparações de complexos organominerais obtidos em condições de laboratório. Este trabalho se preocupa com pesquisa de modelo sobre a formação de complexos sintéticos de ácidos húmicos com minerais: montmorilonita sódica, mica, caulinita em varios pHs (3-7) na presença de ions de alumínio. Seu objetivo foi desenvolver uma reação de suspensão ótima para a síntese de complexos organominerais, para estudar o papel dos ions de Al e procurar determinar o grau de sua complexidade em base de sua condutividade elétrica. Uma importante influência do pH da suspensão foi observada em relação à condutividade elétrica. A maior correlação foi encontrada para preparações organominerais com caulinita e com Al (r = 0,93***). Em termos gerais, o grau de reação dos ácidos húmicos com os minerais depende, antes de tudo, do tipo de mineral, do pH e da presença de Al

The properties of reservoir water in post‑mining excavations of Cambrian and Devonian quartzite sandstones (Holy Cross Mountains)

In the Holy Cross Mountains (southern Poland), there are numerous disused quarries. Some of these are filled with water, and some, despite their nearby location, have extremely diverse physicochemical and chemical properties of their waters. One such object is the Wiśniówka Mała reservoir. Its waters contain large amounts of sulfates (> 700 mg/L) and iron (24 mg/L), which are weathering products of rocks containing metal sulfides (mainly pyrite) in the direct drainage zone. As a consequence, there is an increase in the electrolytic conductivity of the water supplying the reservoir, resulting in very low pH values (< 4). This article presents the detailed limnological characteristics of this reservoir and explains the process that led to its water acidification. A control reservoir, Barcza, was also selected for the tests. Although it is also a post-mining excavation, it has a neutral pH and a low concentration of sulfates and iron. The examined reservoirs differ in the hydrochemical type of waters. The Wiśniówka Mała reservoir represents a sulfate–calcium double-ion type ( SO4 2−–Ca2+) and the Barcza reservoir, a bicarbonate–calcium type ( HCO3 −–Ca2+). The concentrations of the main ions occurring here are shaped by the lithological features of the surrounding rocks (respectively: Upper Cambrian quartzite sandstones with pyrite mineralization zones, Lower Devonian sandstones cut by mudstones and claystones with tuffite inserts)