34 research outputs found

    Separation of Ho3+ in Static Magnetic Field

    Get PDF
    Abstract The rare earths elements (REE) belong to the group of critical metals and they are achieving more and more interest due to their special properties. However, there occur some problems connected with their production. The most difficult phase is separation of REE. It includes a necessity to intensify currently applied processes and looking for new solutions. The present work introduces an idea to use differences in physical properties of the REE ions to get them separated. In the experimental part of the work some efforts were undertaken to analyse results presenting changes of holmium ions concentration under an influence of the magnetic field gradient. There was determined the gradient of magnetic field and concentration of Ho3+ ions depending on initial concentration of the solution and time. A simulation of changing the concentration of holmium ions in the solution under an influence of the magnetic field gradient was performed to compare the mathematical model with the obtained results

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

    Get PDF
    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 CC1 PROJECT – SYSTEM FOR PRIVATE CLOUD COMPUTING

    Get PDF
    The main features of the Cloud Computing system developed at IFJ PAN are described. The project is financed from the structural resources provided by the European Commission and the Polish Ministry of Science and Higher Education (Innovative Economy, National Cohesion Strategy). The system delivers a solution for carrying out computer calculations on a Private Cloud computing infrastructure. It consists of an intuitive Web based user interface, a module for the users and resources administration and the standard EC2 interface implementation. Thanks to the distributed character of the system it allows for the integration of a geographically distant federation of computer clusters within a uniform user environment

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

    Get PDF
    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

    Otrzymywanie cienkich powłok Cu dla elektroniki metodą stałoprądowego rozpylania magnetronowego

    No full text
    The results of the DC magnetron sputtering of copper thin films with different parameters of deposition are presented. The main aim of studies was to determine the influence of current value, time of deposition and target-substrate distance on morphology and grain size of obtained copper thin films. The effects of film's thickness on the resistivity of copper thin films were investigated. The influence of parameters on the rate of deposition was also determined. The possibility of application of resulting films for contact surface in electronic components was discussed. The morphology was characterized by AFM method, the size of Cu deposited grains was calculated using Scherrer's method. The WDXRF method was used for estimate of thickness of sputtered films. The resistivity of obtained films was measured using four probe method.W pracy przedstawiono wyniki badan nad wpływem parametrów napylania magnetronowego cienkich warstw Cu na ich własnosci. Głównym celem przeprowadzonych badan było okreslenie wpływu natezenia pradu, czasu osadzania, odległosci pomiedzy targetem a napylana powierzchnia na wielkosc ziarna oraz morfologie cienkich warstw. Przeprowadzono równiez badania nad wpływem grubosci warstwy na jej opór własciwy. Omówiona została mozliwosc stosowania warstw nanoszonych ta metoda w przemysle elektronicznym. Morfologie otrzymanych warstw charakteryzowano przy uzyciu mikroskopu AFM. Wielkosc ziarna oszacowana została na podstawie wzoru Scherrera. Grubosc warstw wyznaczono technika WDXRF. Do pomiarów oporu własciwego wykorzystano metode pomiaru czteropunktowego

    Stopy Co-Mo oraz Co-Mo-C osadzane w polu magnetycznym o wysokim natężeniu oraz ich właściwości elektrokatalityczne

    No full text
    The article presents results of tests on electrodeposition in a magnetic field of Co-Mo and Co-Mo-C alloys characterised by low overvoltage of hydrogen evolution. Addition of molybdenum and carbon was to lower the values of overvoltage of hydrogen evolution on cobalt. The influence of a magnetic field of high intensity (1 - 12 T) on the deposits composition, structure and morphology was determined. The deposition was conducted in a magnetic field of parallel orientation of the magnetic field forces lines in relation to the working electrode. Electrocatalytic properties of the obtained alloy coatings within the range of hydrogen evolution were tested in a concentrated solution of NaOH. The obtained alloys were analysed with the XRD method, their composition was tested with the WDXRF technique and they underwent observation applying scanning electron microscopy (SEM). The comparison of electrocatalytic properties of Co-Mo alloys with properties of Co-Mo-C ones enabled determining the influence of carbon presence in cathodic deposits on the overvoltage value of hydrogen evolution on them.W artykule przedstawione zostały wyniki badań nad elektroosadzaniem w polu magnetycznym stopów Co-Mo oraz Co-Mo-C charakteryzujących się niskim nadnapięciem wydzielania wodoru. Dodatek molibdenu oraz węgla miałna celu obniżenie wartości nadnapięcia wydzielania wodoru na kobalcie. Określony zostałwpływ pola magnetycznego o wysokim natężeniu (1 - 12 T) na skład, strukturę oraz morfologię osadów. Osadzanie prowadzone było w polu magnetycznym o równoległej orientacji linii siłpola magnetycznego względem elektrody pracującej. Właściwości elektrokatalityczne otrzymanych powłok stopowych w zakresie wydzielania wodoru badano w gorącym stężonym roztworze NaOH. Otrzymane stopy poddano analizie XRD, analizie składu z wykorzystaniem techniki WDXRF oraz obserwacjom z wykorzystaniem skaningowej mikroskopii elektronowej (SEM). Porównanie właściwości elektrokatalitycznych stopów Co-Mo z właściwościami stopów Co-Mo-C pozwoliło na określenie wpływu obecności węgla w osadach katodowych na wartość nadnapięcia wydzielania na nich wodoru

    Kinetic Studies of Pt(IV) Chloride Complex Ions Reduction Reaction Using Potassium Formate

    No full text
    In this paper, the kinetics of the platinum(IV) chloride complex ions reduction reaction was studied. It was shown that the mechanism exhibits autocatalytic character. The presence of metallic platinum in the system significantly increases the reaction rate. The influence of the initial concentration of precursor, reductant, ionic strength, initial concentration of the chloride ions as well as the temperature on the process rate was investigated. The activation energy was determined and is equal to 93.57 kJ/mol. Moreover, the obtained metallic phase was analyzed, and it was observed that it has a micrometric size

    Selected Cyclic Corrosion Tests in Automotive Industry

    No full text
    Corrosion is a main problem for longtime exploration of heat exchangers in automotive industry. Proper selection of accelerated corrosion test for newly developed material is a key aspect for aluminum industry. The selection of material based on corrosion test includes test duration, chemical spray composition, temperature and number of cycles. The paper present comparison of old and newly developed accelerated corrosion tests for testing automotive heat exchanger. The accelerated test results are comprised with heat exchanger taken from market after life cycle

    Steel Packaging Production Process and a Review of New Trends

    No full text
    Packaging steels are thin gauge flat carbon steels coated with tin or chrome on both sides. They are very important raw materials for the production of steel packaging, which allow food to be stored safely and with an extended shelf life. The publication focuses on the production process of ETP and ECCS steel, as well as the problem of corrosion of steel packaging. The topic of legislative changes that require the elimination of chromium (VI) compounds from the steel passivation process was also discussed. The packaging steel industry is currently facing the need to develop a new passivation technology. Leading packaging steel manufacturers in cooperation with varnish and paint suppliers have developed chromium (VI) free technologies by implementing chromium (III) compounds and titanium oxide technology. Authors focus also on new trends and potential development directions for the packaging steel industry

    Katalitycznie aktywne stopy Ni-Re osadzane w zewnętrznym polu magnetycznym

    No full text
    The aim of this work was to obtain Ni-Re binary alloy by a simple method of electrodeposition. Nickel - rhenium alloys have been deposited from nickel sulfamate and ammonium perrhenate electrolyte with citrate-anion additives. The effect of magnetic field superimposed during electrodeposition was studied. The impacts of that parameter on hydrogen evolution process for obtained Ni-Re alloys were examined. The deposited layers were determined by optical and scanning electron microscopy (SEM), X-ray diffraction (XRD) and X-ray fluorescence (XRF).Celem pracy było uzyskanie stopów Ni-Re metoda osadzania elektrolitycznego. Stop niklowo renowy osadzano z elektrolitu zawierającego sulfaminian niklu oraz nadrenian amonu. Stosowano bufor cytrynianowy. Badano wpływ przyłożonego zewnętrznego pola magnetycznego podczas osadzania stopu na wydzielanie wodoru na tak uzyskanym stopie. Badano osadzone warstewki stopowe za pomocą mikroskopu optycznego oraz mikroskopu skaningowego i metodami XRD oraz XRF
    corecore