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The biblical Nazareth is chronologically the first important element of the historical picture of Jesus, the credibility of which is constantly being questioned. The discussion around it carries a trace of debate between minimalists and maximalists. The presented outline of a holistic picture of the history of this settlement, which consists of information and conclusions obtained on the basis of archaeological and historical-literary research in confrontation with the evidence of religious tradition expressed in sacred architecture, facilitates a critical assessment of the credibility of this place.

The salt of formula [H2EDTA2+][HSO4−]2 (dihydrogen ethylenediaminetetraacetate di(hydrogen sulfate(VI)) was used to examine the physicochemical properties of the resulting Ni layer and evaluate the applicability of the salt as a new additive for Watts-type baths. The Ni coatings deposited from baths containing [H2EDTA2+][HSO4−]2 were compared with those obtained from other baths. The nucleation of nickel on the electrode was proven to occur the slowest in the bath that contained the mixture of [H2EDTA2+][HSO4−]2 and saccharin compared with other baths. The addition of [H2EDTA2+][HSO4−]2 alone (bath III) generated a coating with a morphology similar to that obtained from bath I (without additives). Despite the similar morphology and wettability of the Ni-coated surfaces plated from various baths (all Ni coatings were hydrophilic with contact angles in the range of 68 to 77°), some differences in electrochemical properties were noted. The corrosion resistance for the coatings plated from baths II and IV containing saccharin (Icorr = 1.1 and 1.5 µA/cm2, respectively) and the mixture of saccharin and [H2EDTA2+][HSO4−]2 (Icorr = 0.88 µA/cm2), respectively, was similar or even better than the coating obtained from baths without [H2EDTA2+][HSO4−]2 (Icorr = 9.02 µA/cm2).

The category of “Biblical inspiration” dates back to the biblical period. Subsequently, the early Jewish and Christian traditions made many attempts to describe it definitively. Over the centuries, many ways have emerged to understand the nature of the inspiration and to explain its relationship to the human author. One difficulty is the overly simple understanding of the inspiration model of the prophetic texts in the Bible.

This paper describes the use of a combination of two specific layers to protect the surface of low–carbon steel against electrochemical corrosion phenomena, which has not been published in the scientific literature so far. The layers include a black oxide film and siloxane coating, which are formed in the steel blackening and sol–gel processes, respectively. The so–obtained samples were subjected to surface morphology and physicochemical analysis (atomic force microscopy and Fourier-transform infrared spectroscopy) as well as electrochemical measurements, including AC and DC techniques. The physicochemical and surface morphology analysis allowed to prove the presence and adhesion of the siloxane coating to the surface of the black oxide layer, while the results of the electrochemical tests show that low–carbon steel modified this way is characterized by remarkable anti–corrosive properties, comparable to those of stainless steel.

The research and development of new carbon materials of electrochemical capacitors cause a huge interest in chemical power sources causes. The appropriate modification of carbon materials leads to an increase in supercapacitor capacitance. Therefore, activated carbon was modified by ozone treatment. The process of ozonation was carried out for 15, 30, 60, 120 and 240 min. Moreover, activated carbon was also modified by cobalt(II) hydroxide impregnation in order to construct asymmetric electrochemical capacitor. The performance of electrochemical capacitors has been examined by cyclic voltammetry and galvanostatic charge/discharge in 1 M H2SO4, 1 M Na2SO4 and 6 M KOH

The influence of selected types of ammonium ionic liquid (AIL) additives on corrosion and functional parameters of lead-acid battery positive electrode was examined. AILs with a bisulfate anion used in the experiments were classified as protic, aprotic, monomeric, and polymeric, based on the structure of their cation. Working electrodes consisted of a lead-calcium-tin alloy utilized in the industry for manufacturing current collectors of positive electrodes in lead-acid batteries (LABs). This alloy was used in the first part of the study for the evaluation of corrosion intensity and stability of electrolyte with AIL additives. In the second part, the grid made of the examined alloy was covered with positive active mass, the composition of which was modified by selected AIL. The selection of an appropriate substance was made based on parameters such as corrosion potential, corrosion current, polarization resistance, and hydrogen and oxygen evolution potentials. Techniques such as linear sweep voltammetry, corrosimetry, and electrochemical impedance spectroscopy were used. The conducted measurements revealed that polymeric AIL additive had an exceptionally positive influence on the inhibition of the corrosion process in LAB and electrochemical window of the electrolyte. The influence of this compound on the specific capacity and resistance of the active mass was also discussed.

This paper presents a synthesis and characterizes highly amorphous lead dioxide and its use in hybrid electrochemical capacitor C/PbO2. Highly amorphous lead dioxide with a small amount of β-PbO2 was synthesized by galvanostatic deposition from acetate solution. The hybrid supercapacitor was constructed with PbO2 as the positive electrode whereas activated carbon as the negative electrode. The morphology of materials was examined by scanning electron microscopy and their structure was characterized by means of an X-ray diffraction technique. The electrochemical performance of hybrid electrochemical capacitor with synthesized PbO2 was studied by cyclic voltammetry, galvanostatic charge/discharge and electrochemical impedance spectroscopy. To indicate that the amorphous form of lead dioxide was predominant, results were compared to highly crystalline β-PbO2. The hybrid electrochemical capacitor with synthesized material exhibits a much greater specific capacitance, higher specific energy and power than the highly crystalline one. The specific capacitance values obtained for the supercapacitor rose more than twice in favour of amorphous PbO2. Also, long cycling did not influence any of the electrochemical properties of this hybrid electrochemical capacitor, which makes it an interesting energy storage device.

Attempts have been made to find the best procedure for the detection of premature battery capacity loss (the so called &ldquo, PCL&rdquo, ) in AGM-VRLA 48 V batteries operating in telecommunication systems. However, recorded changes in internal resistance and potential did not give clear indications of the beginning of the PCL effect. The obtained correlation between internal resistance and potential derived from used batteries does not show the expected trend in measured parameters. It seems that the application of Electrochemical Impedance Spectroscopy (EIS), which is a faster and non-destructive method, may solve this problem. It is demonstrated that the change in internal resistance (which is an indicator of the state of health (SoH)) can be determined from EIS spectra during continuous operation of 12 V monoblocks in a backup power source of a base transceiver station (BTS).

This paper presents multistage hydrometallurgical separation of Co(II) from wastewater, achieved in an integrated system containing diffusion dialysis (DD) to decrease the acidity of the industrial effluent – pregnant leach solution (PLS), followed by precipitation of Al(III), Fe(III) and Cr(III) hydroxides, selective extraction of Co(II) with bis(2,4,4-trimethylpentyl)phosphinic acid (Cyanex 272), stripping of Co(II) from the loaded organic phase to form an electrolyte. DD results indicate that minimum metal ion content in the dialysate and high concentration of H+ (1.5−3 M) can be achieved by conducting the process at a low flow rate, but for a longer time. The feed after DD was effectively purified by precipitation of Cr(III), Al(III) hydroxides, and some admixtures of Cu(II) and Fe(III) to ensure that those metals will not disturb the liquid-liquid extraction of Co(II) at pH 5.2. High distribution ratio values for Co(II) extraction mean that ions of this metal can be selectively separated from the remaining ions present in the feed, especially Ni(II), and transported to the organic phase. The application of H2SO4 solution and the dialysate as stripping phases indicates that the dialysate more efficiently stripped most of the metal ions from the extract, thus forming Co(II) rich electrolyte for further electrodeposition of the metal. Finally, Co(II) electrowinning from a model stripping solution was investigated and the preliminary results showed that good quality metallic cobalt can be deposited.

Peruvian Maca crops (Lepidium peruvianum), grown in two geographically-distant cultivation sites located at similar altitudes in the highlands of the Peruvian Andes (Junin at 4,200 m a.s.l. and Ancash 4,150 m a.s.l.), were used in the study. Four prime Maca phenotypes, distinguished by hypocotyl colours labelled as “Yellow”, “Purple”, “Red” and “Black” were selected to determine distribution in levels and corresponding ratios between individual Glucosinolates (Glucotropaeolin and m-methylglucotropaeolin) in an attempt to identify four Peruvian Maca phenotypes from analyses of powdered hypocotyls. There were highly significant differences (P

This paper examines the influence of aprotic solvents on the spectroscopic properties as well as the energy deactivation of two free-base corrole dyes substituted with C6F5 and/or 4-NO2C6H4 groups. Absorption, fluorescence and laser-induced optoacoustic spectroscopy have been used to follow the singlet and triplet states of fluorine corroles belonging to the A2B and A3 type in toluene (TL), chloroform (CL), dimethylformamide (DMF), dimethyl sulfoxide (DMSO) and also in solvent mixtures. Changes in the absorption and fluorescence spectra are influenced by the type of solvent mixture. The fluorescence behaviors of the two investigated corroles were extremely different - fluorescence of the nitro-corrole in TL is dramatically quenched in the presence of DMF. In contrast, fluorescence quenching of fluorine corroles in DMF-TL mixtures is substantially weakened. Absorption, fluorescence, triplet population as well as singlet oxygen generation parameters are evaluated. The spectral experimental data are supported by quantum chemical calculations - time-dependent density functional theory (TD-DFT) and cyclic voltammetry experiments. The presented results are discussed from a viewpoint of aggregation, tautomerization, and deprotonation effects occurring in the corroles.

The aim of the presented study was to develop a feasible and technologically viable modification of a 12 V lead-acid battery, which improves its energy density, capacity and lifetime. The proposed solution promotes the addition of a protic ammonium ionic liquid to the active mass of the positive electrode in the lead-acid battery. The experiments included the synthesis and characterisation of several protic ammonium-based ionic liquids, which differed in terms of the length of the side chain in the cation. A three-stage procedure of the battery test was proposed. First, a laboratory model with a Pb-Ca-Sn alloy as a working electrode and ionic liquids as additives to the electrolytes enabled the selection of the best modifier. Addition of the best-studied ionic liquid, N,N-dimethylhexadecylammonium sulfate, suppressed the corrosion of current collector material by approx. 70% and increased the overpotential of hydrogen evolution reaction. Afterwards, tests on 2 V model lead-acid cells were carried out to compare the various concentrations of the ionic liquid in the active mass. Finally, tests on 12 V lead-acid batteries with 0.5% of protic ionic liquid were performed to evaluate the final influence on the full, industrial product.

The content of essential oil and valerenic acids and the yield of roots were analyzed in valerian cultivar ‘Polka’ and strain no. 4 during the nine following phases: the beginning of vegetation, spring rosette, pedicel development, the beginning of flowering, full bloom, seed harvest, three weeks after the seed harvest, fall rosette, and after the first frost. The yield of valerian roots was different at the investigated phases and in years of cultivation, while tested genotypes produced similar root yields. The highest contents of essential oil and valerenic acids were obtained at different phases by the tested genotypes: strain no. 4 in full bloom (1.3% and 0.266%, respectively) and cultivar ‘Polka’ three weeks after seed harvest (1.25%) and during seed harvest (0.218%). The lowest contents of the investigated substances were detected at the beginning of growth and after the first frost in both genotypes. The obtained results revealed significant differences in essential oil and valerenic acids...

The effect of the presence of quaternary ammonium chlorides (QACl) and saccharin on various electrodeposition parameters for nickel deposition on a stainless steel cathode from a Watts-type plating bath was investigated. The parameters included cathodic current efficiency, throwing power of the bath, cathodic polarization, crystal orientation, and quality of the deposit. The following additives were investigated: saccharin, 1-alkyloxymethyl 3-benzyl imidazolium chlorides [alkyl R =C 2 , C 6 , C 10 ], 1-decyloxymethyl 3-alkyl imidazolium chlorides [alkyl R =C 2 , C 6 , C 10 ], 1-cycloheksyloxymethyl 3-alkyl imidazolium chlorides [alkyl R =C 2 , C 6 , C 10 ], benzyl-dimethyl-alkyl ammonium chloride [alkyl R =C 2 , C 4 , C 8 ], benzyloxymethyl-dimethyl-alkyl ammonium chlorides [alkyl R =C 2 , C 4 , C 8 ], benzyl-dimethyl-alkyloxymethyl ammonium chlorides [ R =C 2 , C 4 , C 8 ]. The results indicated that only one type of QACl fulfilled all requirements to be acceptable, namely: benzyl-dimethyl-alkyloxymethyl chlorides, and especially benzyl-dimethyl-buthyloxymethyl chloride. The mechanism of the action of this additive has also been discussed.

Objectives In recent years there has been an increase in the use of dental casting alloys in prosthodontic treatment. Many patients have metals or alloys, as well as amalgam fillings, in their mouth, and will have them for many years. The aim of this study was to evaluate and compare, in vitro, the galvanic corrosion behavior of chromium–cobalt alloy (Remanium GM 380) and chromium–nickel alloy (Remanium CS) when bound together or coupled with silver-based amalgam (Amalcap plus). Methods An electrochemical characterization of the alloys was performed by potentiostatic and potentiodynamic methods, i.e. the open circuit potential (OCP), the corrosion potential ( E CORR ), corrosion current density ( i CORR ) and corrosion resistance ( R P ). The electromotive force (EMF) of the bimetallic cells was also tested. Electroanalytical techniques were used to estimate the release of any respective element from the dental alloys under study into the artificial saliva solution. Results It was found that a bimetallic cell consisting of Remanium CS and Remanium GM 380 alloys has a very low EMF (a few mV) and is not a potential source of galvanic currents in the oral cavity. However, galvanic cells prepared from Amalcap plus and Remanium CS or Remanium GM 380 showed a much greater EMF: 104 and 109 mV, respectively. This clearly indicates that in these latter cases it is possible to expect some metal ions in the saliva solution as a result of the work of galvanic currents. It was found, by adsorptive stripping voltammetry analysis, that nickel or cobalt, depending on the alloy used, appeared in the saliva solution and increased in concentration over time. Significance The results indicate that the correct design and use of dental alloys are important when determining the appropriate treatment for a specific patient.

Activated carbon modified by ozone treatment was examined. The process was carried out in a glass reactor under a continuous flow of ozone through a bed of activated carbon for 15, 30, 60, 120, and 240 min. The modified and unmodified carbon materials were characterized by Raman spectroscopy and observed by scanning electron microscopy (SEM). Thermogravimetric analysis was used to estimate the presence of oxygen groups in the carbon structure. The surface area and pore size distribution were examined by nitrogen adsorption method at 77 K. Moreover, Fourier transform infrared (FTIR) spectroscopy was used to estimate the functional groups of modified activated carbon. The carbon content was estimated using the elemental analysis. The process of ozonation increases oxygen functionalities, thus the activated carbon was tested as electrodes for an electrochemical capacitor. The performance of an electrochemical capacitor was estimated by selected alternating (AC) and direct current (DC) methods in 1 M H2SO4, 1 M Na2SO4, and 6 M KOH electrolytes.