14 research outputs found

    A copper alloy light cannon from Grodno: an example of early firearms from Eastern Europe

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    The paper discusses a recent find of a copper alloy light cannon discovered at the Old Castle in Grodno, Belarus. The research aim was to analyse the artefact in all its possible aspects, including archaeological and historical contexts, possible analogies, and the gun’s technology of manufacture. This latter was done against a broad comparative background of what is known on manufacturing technologies of late medieval and modern period copper alloy firearms. First, the archaeological and historical contexts of the discovery are dealt with. Then, the morphology and typochronology of the cannon are discussed and relevant analogies are proposed. Next, the technology of manufacture of the cannon is studied on the basis of metallographic examinations and EDS analyses of the metal’s elemental composition. It was found out that the artefact had been made of leaded copper. The cannon can be dated with reasonable certainty to the late 14th c., as implied both by the find context, the morphology and the chemical composition of the artefact. Its deposition can be related to fights over the Old Castle in Grodno in this period, waged by Teutonic, Polish and Lithuanian forces. It can tentatively be proposed that the cannon was manufactured in a Teutonic Order’s workshop, but further research is necessary to verify this supposition

    ELECTROCHEMICAL CODEPOSITION OF MOLYBDENUM AND SELENIUM

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    The electrodeposition of the Mo-Se thin films from sulfate solution containing Na2MoO4 and H2SeO3 was studied. The process of deposition were conducted under potentiostatic condition on copper electrode. The effect of different potential, pH and time of deposition were examined. The deposits were characterized by X-ray diffraction, X-ray fluorescence and scanning electron microscopy

    The Mechanism of Phase Transfer Synthesis of Silver Nanoparticles Using a Fatty Amine as Extractant/Phase Transfer Agent

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    The paper presents the research results on synthesizing silver nanoparticles in aqueous solutions and their extraction into the organic phase. Studies have shown that it is best to perform the extraction process using n-hexane > cyclohexane > toluene > chloroform > ethyl acetate. The results show a correlation between the dielectric constant of the organic phase and its ability to extract nanoparticles. The lower the dielectric constant is, the higher the extractability. The hydrodynamic radius of the silver nanoparticles changes after transfer to the organic phase, depending greatly on the organic phase used. The extraction mechanism is complex and multi-step. As the first step, the Ag nanoparticles are transferred to the phase boundary. As the second step, the octadecylamine (ODA) molecules adsorb on the silver nanoparticles (AgNPs) surface. The change in particle shape was also noted. This suggests that the interfacial processes are more complex than previously reported. Below the initial concentration of ODA 2 × 10−4 M, the formation of a third phase has been observed. In a one-stage experiment, the concentration of silver nanoparticles after transferring to the organic phase was increased 500 times in about 10 s. The role of the concentration of ODA, therefore, is not only a measure of the extraction efficiency and productivity but functions as an enabler to maintain favorable biphasic processing, which underlines the role of the solvent again

    The mechanism of phase transfer synthesis of silver nanoparticles using a fatty amine as extractant/phase transfer agent

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    The paper presents the research results on synthesizing silver nanoparticles in aqueous solutions and their extraction into the organic phase. Studies have shown that it is best to perform the extraction process using n-hexane > cyclohexane > toluene > chloroform > ethyl acetate. The results show a correlation between the dielectric constant of the organic phase and its ability to extract nanoparticles. The lower the dielectric constant is, the higher the extractability. The hydrodynamic radius of the silver nanoparticles changes after transfer to the organic phase, depending greatly on the organic phase used. The extraction mechanism is complex and multi-step. As the first step, the Ag nanoparticles are transferred to the phase boundary. As the second step, the octadecylamine (ODA) molecules adsorb on the silver nanoparticles (AgNPs) surface. The change in particle shape was also noted. This suggests that the interfacial processes are more complex than previously reported. Below the initial concentration of ODA 2 × 10−4 M, the formation of a third phase has been observed. In a one-stage experiment, the concentration of silver nanoparticles after transferring to the organic phase was increased 500 times in about 10 s. The role of the concentration of ODA, therefore, is not only a measure of the extraction efficiency and productivity but functions as an enabler to maintain favorable biphasic processing, which underlines the role of the solvent again

    Synthesis of Co–Fe 1D Nanocone Array Electrodes Using Aluminum Oxide Template

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    Porous anodic alumina oxide (AAO) obtained via two-step anodization is a material commonly used as a template for fabricating 1D nanostructures. In this work, copper and cobalt-iron 1D nanocones were obtained by an electrodeposition method using AAO templates. The templates were produced using two-step anodization in H2C2O4. The Co–Fe nanostructures are characterized by homogeneous pore distribution. The electrocatalytic activity of the produced nanomaterials was determined in 1 M NaOH using the linear sweep voltammetry (LSV) and chronopotentiometry (CP) methods. These materials can be used as catalysts in the water-splitting reaction. The sample’s active surface area was calculated and compared with bulk materials

    Influence of the Applied External Magnetic Field on the Deposition of Ni–Cu Alloys

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    Ni–Cu alloys are suitable candidates as catalysts in hydrogen evolution reaction. Because of the different magnetic properties of Ni and Cu, the influence of an applied external magnetic field on the synthesis Ni–Cu alloys was studied. The coatings were prepared with visible changes in their appearance. The differences between the observed regions were studied in terms of morphology and chemical composition. In addition, the overall chemical and phase compositions were determined using X-ray fluorescence and X-ray diffraction methods, respectively. The catalytic activity was measured in 1 M NaOH using linear sweep voltammetry. The contact angle was determined using contour analysis. All samples were hydrophilic. Hydrogen evolution started at different times depending on the area on the surface. It started earliest on the coating obtained in parallel to the electrode magnetic field at 250 mT. We found that when the Lorenz force is maximal, Cu deposition is preferred because of the enhancement of mass transport

    Inhaler use technique course: an effective postgraduate training solution for pharmacists to enhance therapeutic outcomes as part of patient education

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    Abstract Background Patients with asthma and chronic obstructive pulmonary disease could benefit from education on using inhalers provided by pharmacists. However, pharmacists may have limited competencies, indicating the necessity to implement appropriate postgraduate courses. The study aimed to evaluate an inhaler use course for pharmacists, including its impact on participants’ knowledge and satisfaction. Methods The study involved 261 pharmacists from community pharmacies and was conducted between September 2019 and March 2021. A pre-post analysis of their knowledge of the topic was applied. Additionally, at the beginning of the course, participants were asked about their educational needs, and at the end, they completed a satisfaction survey. The preferred learning formats indicated by participants were interactive workshops and lectures. Results As a result of the course, both their actual and self-assessed level of knowledge significantly increased. The percentage of correct answers in the test before the training was 24.4%, while after, it was 84.3% (p < 0.0001). Before the course, their average self-assessed level of knowledge was 52.0%, and after the training, it increased to 90.0% (p < 0.0001). Almost all respondents stated that the course met their expectations. They estimated their satisfaction at 94.0% and the usefulness of the provided information at 98.0%. Conclusions Improved preparation of pharmacists resulting from their participation in the course can contribute to providing more professional advice to patients, thereby positively influencing the pharmaceutical care process in community pharmacies

    The Mechanism of Phase Transfer Synthesis of Silver Nanoparticles Using a Fatty Amine as Extractant/Phase Transfer Agent

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    The paper presents the research results on synthesizing silver nanoparticles in aqueous solutions and their extraction into the organic phase. Studies have shown that it is best to perform the extraction process using n-hexane > cyclohexane > toluene > chloroform > ethyl acetate. The results show a correlation between the dielectric constant of the organic phase and its ability to extract nanoparticles. The lower the dielectric constant is, the higher the extractability. The hydrodynamic radius of the silver nanoparticles changes after transfer to the organic phase, depending greatly on the organic phase used. The extraction mechanism is complex and multi-step. As the first step, the Ag nanoparticles are transferred to the phase boundary. As the second step, the octadecylamine (ODA) molecules adsorb on the silver nanoparticles (AgNPs) surface. The change in particle shape was also noted. This suggests that the interfacial processes are more complex than previously reported. Below the initial concentration of ODA 2 × 10−4 M, the formation of a third phase has been observed. In a one-stage experiment, the concentration of silver nanoparticles after transferring to the organic phase was increased 500 times in about 10 s. The role of the concentration of ODA, therefore, is not only a measure of the extraction efficiency and productivity but functions as an enabler to maintain favorable biphasic processing, which underlines the role of the solvent again

    Substrates with different magnetic properties versus iron-nickel film electrodeposition

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    The hereby work presents the iron-nickel alloys electroplated on the different metallic substrates (aluminium, silver, brass) using galvanostatic deposition, with and without presence of the external magnetic field (EMF). The films were obtained in the same electrochemical bath composition - mixture of iron and nickel sulphates (without presence of additives) in the molar ratio of 2 : 1 (Ni : Fe), the electric current density (50.0 mA/cm2), and the time (3600 s). The mutual alignment of the electric (E) and magnetic field (B) was changeable - parallel and perpendicular. The source of EMF was a set of two permanent magnets (magnetic field strength ranged from 80 mT to 400 mT). It was analysed the surface microstructure, composition, morphology, thickness and the mechanical properties (roughness, work of adhesion). The surface morphology and the thickness of films were observed by Scanning Electron Microscopy (SEM) and Confocal Laser Scanning Microscopy (CLSM). The elemental composition of all FeNi films was measured using Wavelength Dispersive X-Ray Fluorescence (WDXRF). The crystalographic analysis of the deposits was carried out by X-Ray Diffraction. Depending on the used substrate, modified external magnetic field orientation influenced the tribological and physio-chemical properties of the deposited layers. The diamagnetic substrates and EMF application reduced the FeNi thickness and the average crystallites size, in contrast to the paramagnetic substrate. Parallel EMF increased the value of the tribological parameters for CuZn and Ag but decreased for Al. The content of FeNi structure was rising in the case of diamagnetic substrate and the dependence was opposite on the paramagnetic substrate
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