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Wyniki wyszukiwania dla: METAL STRUCTURES
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Determination of t8/5 cooling times for underwater local dry welding of steel
PublikacjaKnowledge of thermal history is the basic condition for studying the structure - properties of welded joints. The determinant of thermal history is the thermal cycle, whose in-situ measurements are still a big challenge. Water as the welding environment complicates this issue even more. The article presents a method to determine an equation for calculating t8/5 cooling times for underwater gas metal arc welding of unalloyed steels...
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Organic pollutants photodegradation increment with use of TiO2 nanotubes decorated with transition metals after pulsed laser treatment
PublikacjaAmong various titanium(IV) oxide (TiO2, titania) structures, 1D nanotubes (TiO2 NTs) produced during the two-electrode anodization process, are extensively utilized in sensors or supercapacitors as well as in photo(electro)catalytic water splitting. However, due to wide bandgap and fast electron-hole recombination additional modifications, mostly concerned on materials surface, are required. According to the recent research, TiO2...
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An insight into the mixed quantum mechanical-molecular dynamics simulation of a ZnII-Curcumin complex with a chosen DNA sequence that supports experimental DNA binding investigations
PublikacjaAn important aspect of research pertaining to Curcumin (HCur) is the need to arrest its degradation in aqueous solution and in biological milieu. This may be achieved through complex formation with metal ions. For this reason, a complex of HCur was prepared with ZnII, that is not likely to be active in redox pathways, minimizing further complications. The complex is monomeric, tetrahedral, with one HCur, an acetate and a molecule...
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Discussion of Derivability of Local Residual Stress Level from Magnetic Stray Field Measurement
PublikacjaThe NDT procedure dubbed ‘metal magnetic memory’ method and the related ISO 24497 standard has found wide industrial acceptance in some countries, mainly in Russia and China. The method has been claimed by some researchers (Roskosz and Bieniek in NDT&E Int 45:55–62, 2012; Wilson et al. in Sens Actuators A 135:381–387, 2007) as having potential for quantitative determination of local residual stress state in engineering structures,...
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Starch–metal complexes and metal compounds
PublikacjaRecently, metal derivatives of starch evoked considerable interest. Such metal derivatives can take a form of starch compounds bearing metal atoms and metal carrying moieties either covalently bound or complexed. Starch metal complexes may have a character of either Werner, inclusion, sorption or capillary complexes. In this publication, preparation, structure, properties and numerous current and potential applications of those...
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Implementation of Hermite-Ritz method and Navier’s Technique for Vibration of Functionally Graded Porous Nanobeam Embedded in Winkler-Pasternak Elastic Foundation Using bi-Helmholtz type of nonlocal elasticity
PublikacjaPresent study is devoted to investigating the vibration characteristics of Functionally Graded (FG) porous nanobeam embedded in an elastic substrate of Winkler-Pasternak type. Classical beam theory (CBT) or Euler-Bernoulli beam theory (EBT) has been incorporated to address the displacement of the FG nanobeam. Bi-Helmholtz type of nonlocal elasticity is being used to capture the small scale effect of the FG nanobeam. Further, the...
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Assessment of hydrogenation of deposited metal of P 62 MR covered electrodes
PublikacjaThe determination of diffusible hydrogen content in deposited metal of P 62 MR covered electrodes for manual metal arc welding by mercury method was carried out. The test results indicate that covered electrodes 62 P MR grade generate a mean of 4.02 ml/100g of diffusible hydrogen in deposited metal, which is consistent with H5 class.
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Metal nanoparticles-assisted early diagnosis of diseases
PublikacjaEarly diagnosis is essential for the effective illness treatment, but traditional diagnostic approaches inevitably have major downsides. Recent advancements in nanoparticle-based biosensors have created new opportunities for accelerating diagnosis. High surface area, exceptional sensitivity, high specificity, and optical characteristics of metal and metal oxide nanoparticles have made it possible to detect a variety of health conditions...
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Ranking of Heterogeneous Catalysts Metals by Their Greenness
PublikacjaCatalysis is very important process in industry and laboratory practice, especially from the point of green chemistry principles. However, eco-friendly character of heterogeneous catalysts, containing transition metal components has not been evaluated, yet. Therefore, we perform a comprehensive assessment of 18 heterogeneous metal catalysts (Pd, Pt, V, Co, Ni, Mo, Ru, Mn, Au, Cu, Cd, Zr, Fe, Rh, Ir, Sn, Zn, Ag) using multicriteria...
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Microstructure and Mechanical Properties of Combined GTAW and SMAW Dissimilar Welded Joints between Inconel 718 and 304L Austenitic Stainless Steel
PublikacjaA dissimilar welded joint of Inconel 718 and 304L austenitic stainless steel was prepared using a combined procedure with the gas tungsten arc welding and shielded metal arc welding processes by employing the Ni-based fillers: ERNiCr-3 and ENiCrFe-3. The welded joints were investigated for metallographic testing and mechanical properties, and a relationship was established between the microstructure and the resultant mechanical...
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Nickel phase deposition on V2CTx/V2AlC as catalyst precursors for a dry methane reforming: The effect of the deposition method on the morphology and catalytic activity
PublikacjaDry reforming of methane (DRM) is a promising alternative technology for the production of syngas with simultaneous utilization of two main greenhouse gases (CH4, CO2). However, DRM technology is still an industrially immature process due to the lack of stable and active catalyst. Therefore, the search for new catalytic materials is of great research interest. Recently, MAX and MXenes materials are increasingly being tested as...
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Synthesis of CoFe2O4 Nanoparticles: The Effect of Ionic Strength, Concentration, and Precursor Type on Morphology and Magnetic Properties
PublikacjaThe present study highlights the effect of metal precursor types (SO4 2¯, Cl¯, and NO3¯), their concentration, and the influence of ionic strength of reaction environment on the morphology, surface, and magnetic properties of CoFe2O4 particles. The magnetic nanoparticles were obtained by chemical coprecipitation in alkaline medium at increasing metal concentration in the range of 0.0425 mol·dm-3 to 0.17 mol·dm-3 and calcination...
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The effect of preparation route on structure and photocatalytic properties of bimetallic nanoparticles (Au/Pd, and Au/Pt) deposited at TiO2 surface
PublikacjaNoble metal nanoparticles have often been used to enhance the photocatalytic activity of TiO2 and to extend the absorption wavelength from the ultraviolet to visible region. Bimetallic nanoparticles, composed of two different metal elements, can exhibit peculiar electronic, optical, and catalytic or photocatalytic properties that are absent in the corresponding monometallic nanoparticles. In this work we show the effect kind and...
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The effect of metal cluster deposition route on structure and photocatalytic activity of mono- and bimetallic nanoparticles supported on TiO2 by radiolytic method
PublikacjaTiO2 (P25) was modified with small and relatively monodisperse mono- and bimetallic clusters (Ag, Pd, Pt, Ag/Pd, Ag/Pt and Pd/Pt) induced by radiolysis to improve its photocatalytic activity. The as-prepared samples were characterized by X-ray fluorescence spectrometry (XRF), photoluminescence spectrometry (PL), diffuse reflectance spectroscopy (DRS), X-ray powder diffractometry (XRD), scanning transition electron microscopy (STEM)...
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Lower rim substituted p-tert-butyl-calix[4]arene. Part 17. synthesis, extractive and ionophoric properties of p-tert-butylcalix[4]arene appended with hydroxamix acid moieties
PublikacjaThe synthesis and characterization of four p-tert-butylcalix[4]arene-hydroxamic acidc are reported. The dependence of the metal ion binding, assessed by liquid extraction of the metal nitrates from water into dichloromethane in individual and competitive experiments, on the ligand structure, is presented. The results showed that those ligands could be successfully used in separation process of trnasition and heavy metals often...
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Removal and speciation of heavy metals in the constructed wetland treating landfill leachate
PublikacjaThe results of heavy metals removal and speciation of metals at two treatment wetlands receiving landfill are discussed. The first TW is a surface flow facility consisting of 10 ponds. The next TW is a newly constructed pilot-scale facility consisting of three beds with alternately vertical and horizontal sub-surface flow. The metals concentrations were analysed in leachate(both TWs) and bottom sediments (surface flow TW). Seasonal...
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Catalytic Asymmetric Synthesis of Isochroman Derivatives
PublikacjaThe isochroman scaffold constitutes an important structural unit, which is present in various bioactive natural products and synthetic pharmaceutical compounds exhibiting wide arrays of biological properties. Hence the synthesis of this class of heterocyclic compounds in a stereoselective fashion is highly significant and desirable. In the last decade, a substantial advancement has been witnessed ln the catalytic asymmetric...
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Experimental investigation and process parameter optimization of sheet metal bending by line heating method
PublikacjaThe present study is concerned with the experimental investigation of sheet metal deforming by line heating method that incorporates the combined effect of traverse speed of the torch, thickness of the sheet metal, and the number of passes of the torch. For the numerical analysis of metal bending by line heating, the
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Bioaccumulation of metals in tissues of marine animals, Part II - metal concentrations in animal tissues
PublikacjaThe bioaccumulation of metals in an animal depends on a multitude of factors: biotic ones, like its body dimensions and mass, age, sex, diet, metabolism and position in the trophic web, as well as abiotic ones such as the distribution of metals in its environment, the salinity, temperature and pH of the water, habitat type, interactions with other metals. But it is diet that has the greatest influence on the accumulation of metals...
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Fast-SEC coupled to ICP-MS for selected metal determination and its stability over time in polish wine
PublikacjaMetal ions contribute to the wine browning (as reaction catalysts), turbidity (in complexes), and astringency (due to inter- action with tannins). Being aware that bioavailability and metabolism of metal ions in the human body are strictly related with their concentration and the form they occur it is important to monitor not only the total content of metals but also their speciation. Thus, we can obtain more information about...
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Cation sensing by diphenyl-azobenzocrowns
PublikacjaMetal cations complexation and proton binding by 13- and 16-membered diphenyl-azobenzocrowns and diphenyl-hydroxyazobenzocrowns were studied in acetonitrile using spectroscopic methods: UV–vis spectroscopy, spectrofluorimetry, and 1H NMR spectroscopy. Phenyl moieties in benzene rings were found to affect binding strength alkali and alkaline earth metal cations and hydrogen ion, and affect tautomeric equilibrium of hydroxyazobenzocrowns....
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Nanoparticles preparation using microemulsion systems
PublikacjaMetallic nanoparticles become of current interests because they exhibit unique properties compared with those of metal atoms or bulk metal due to the quantum size effect and their large surface area, which make them attractive for applications in optics, electronics, catalysis biology and medicine. TiO2 has been used for environmental remediation purposes such as in the purification of water and air and also solar-to chemical energy...
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The occurrence of heavy metals and metal-resistant bacteria in water and bottom sediments of the Straszyn reservoir (Poland)
PublikacjaThe aim of this study is investigate the distribution of selected heavy metals (zinc, copper, lead, cadmium) and metal-resistant bacteria in water and bottom sediments of drinking water reservoir for Gdańsk (Poland). The research area - Straszyn Lake is a dam reservoir on Radunia river, of the total volume of 3 mln m3. Sediment and water sampling took place between May and October 2013 (eight series). Regarding metal concentration...
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Determination of metals in water samples by atomic absorption spectrometry and flame emission spectrometry
PublikacjaMetal species in environmental waters are relevant to characterize the metal toxicity, the mobility between different environmental compartments, and for remediation purposes in case of contamination. The concentration of many trace metals in natural water samples are generally at µg/l level. The paper describes determination of metals in water samples based on flame atomic emission and flame atomic absorption spectrometry.
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Recent advancements in molecularly imprinted polymers for the removal of heavy metal ions and dyes
PublikacjaContamination set off by highly toxic metal ions and dyes is a big threat to the environment and living beings. Various industries like metal plating, mining, pesticides, battery manufacturing, and dyeing release metal ions and toxic dyes directly into the water. It is necessary to remove these toxic substances from the environment. Molecular imprinting technology (MIT) got a lot of attention in the last two decades because of...
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Unveiling the Pool of Metallophores in Native Environments and Correlation with Their Potential Producers
PublikacjaFor many organisms, metallophores are essential biogenic ligands that ensure metal scavenging and acquisition from their environment. Their identification is challenging in highly organic matter rich environments like peatlands due to low solubilization and metal scarcity and high matrix complexity. In contrast to common approaches based on sample modification by spiking of metal isotope tags, we have developed a two-dimensional...
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Mixed conductivity in tungstenite-phosphate glasses containing alkali metal ions
PublikacjaThe conductivity of glasses in the 50WO3-(50-x)P2O5-xA2O (A = Na, K, Cs) system has been investigated as a function of composition. It is shown that in tungstenite-phosphate glasses containing different alkali metal ions the conductivity decreases with an increase in the alkali metal ion content. A decrease in conductivity is larger for heavier ions and reaches more than seven orders of magnitude in the case of glass containing...
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Diffusible hydrogen management in underwater wet self-shielded flux cored arc welding
PublikacjaThis article reports the effect of underwater wet welding parameters and conditions on the diffusible hydrogen content in deposited metal for welding with a self-shielded flux cored wire. The diffusible hydrogen content in deposited metal was determined using the glycerin method according to the Plackett-Burman design determining the significance of the effect of the stick out length, welding current, arc voltage, travel speed...
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Determination of moisture resistance of covered electrodes according to PN-EN ISO 14372
PublikacjaMoisture present in the electrode covering is one of the sources of diffusible hydrogen in welded joints. In order to study the diffusible hydrogen content in deposited metal, a stand for moisturizing covered electrodes, in accordance with the PN-EN ISO 14372 standard, was built. After the stand was completed, a test of moisturizing the electrodes was carried out and measurements of the diffusible hydrogen content in deposited...
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Study on Microstructure-Property Relationship of Inconel 617 Alloy/304L SS Steel Dissimilar Welds Joint
PublikacjaWelding of Inconel 617 (IN617) alloy and austenitic 304L SS steel has been attempted using the autogenous Laser Beam Welding (LBW) process. Characterization of dissimilar weldments was performed on either side of the fusion boundaries. The metallographic results showed that the inhomogeneous microstructure formation for weld metal contained columnar and cellular dendrites near the interface, whilst the columnar, cellular and equiaxed...
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Nitrogen dioxide gas-sensing detection with GO modified CuO thin films
PublikacjaGas sensors have been continuously developed over the last few decades for several applications including air quality monitoring, automotive industry and recently for medical use. Gas sensors are usually based on metal oxides (MOXs), such as SnO2, TiO2, ZnO, WO3, CuO. Recently, new materials such as graphene oxide and heterostructures of graphene oxide and metal oxides are utilized for gassensing applications.
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Analysis of guided wave propagation in adhesive joints of steel rods
PublikacjaThe aim of the study is the elastic wave propagation in adhesive joints of metal rods that are one of the simplest kind of glue connections. They are consisted of two metal members and an adhesive layer joining two parts together. The analysis is directed to technical diagnostics of such type of connections. Longitudinal and transversal guided waves were excited in prepared joints. Signals of propagating waves were registered in...
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Application of 3D printing metal powder technology in the manufacture of components with complex geometries
PublikacjaThe possibilities of using 3D printing powder technologies for making objects with complex geometries were presented. For this purpose, selected examples of elements with different geometries were used, which were built using metal powder methods – DMLS (direct metal laser sintering) / SLM (selective laser melting). Simultaneously, the indicated elements concern those areas of industry where 3D printing technology has been widely...
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Diiodo-BODIPY Sensitizing of the [Mo3S13]2– Cluster for Noble-Metal-Free Visible-Light-Driven Hydrogen Evolution within a Polyampholytic Matrix
PublikacjaWe report on a photocatalytic setup that utilizes the organic photosensitizer (PS) diiodo-BODIPY and the non-precious-metal-based hydrogen evolution reaction (HER) catalyst (NH4)2[Mo3S13] together with a polyampholytic unimolecular matrix poly(dehydroalanine)-graft-poly(ethyleneglycol) (PDha-g-PEG) in aqueous media. The system shows exceptionally high performance with turnover numbers (TON > 7300) and turnover frequencies (TOF...
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Fabrication and photoactivity of organic-inorganic systems based on titania nanotubes and PEDOT containing redox centres formed by different Prussian Blue analogues
PublikacjaHerein, the heterojunction composed of an inorganic substrate: ordered hydrogenated titania nanotubes (H-TiO2NTs) and a deposited organic film: poly(3,4-ethylenedioxythiophene) (PEDOT) is reported. The conducting polymer is modified with different transition metal haxacyanoferrates (Mehcf), wherein as metal: copper, iron, cobalt and nickel are introduced. The presence of various metal centres provides characteristic redox activity...
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Multi-Analytical Techniques for the Study of Burial Clothes of Polish King Sigismund III Vasa (1566–1633) and His Wife Constance Habsburg (1588–1631)
PublikacjaThe subjects of this research are the burial clothes of Polish King Sigismund III Vasa and his wife Constance, which were woven and embroidered with silk and metal threads. Fragments of the textiles underwent spectroscopic, spectrometric, and thermogravimetric analyses. The hydrofluoric acid extraction method was improved to isolate various classes of dyes from the textile samples that had direct contact with human remains. High-performance...
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Pipeline geometry defects in high resolution pig's data
PublikacjaMost of the pipelines have been inspected at least once using intelligent pigging. The problem of specific software for interactive presentation, analysis and comparison of features revealed during the consecutive geometry surveys is emphasized. Capabilities of a simultaneous measurement of internal geometry and metal loss features in a single run are illustrated. Advantages of application of statistical characteristics of both...
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NOBLE METAL MODIFIED TiO2 FOR PHOTOCATALYTIC AIR PURIFICATION
PublikacjaTiO2 was surface modified with silver, gold, palladium and platinum ion clusters to improve its photocatalytic activity. The effect of metal content, the kind of dopant used during preparation procedure on the photoactivity were investigated. in toluene removal which was used as a model volatile organic compound. Toluene, at the concentration of about 100 ppm, was irradiated over noble metal modified TiO2 using light-emitting diodes...
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Noble metal modified TiO2 microspheres: Surface properties and photocatalytic activity under UV-vis and visible light
PublikacjaComposite photocatalysts that consist of TiO2and noble metal nanostructures have been considered tobe the promising and pivotal material for accessible enhancement of the efficiency in the photocatalyticprocess carried out in the aqueous and gas phases. In this work we fabricated porous TiO2microspheresthrough a hydrothermal process followed by photochemical reduction of noble metal nanoparticles atthe TiO2surface. The morphology...
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Preparation, characterization and photocatalytic activity of TiO2 microspheres decorated by bimetallic nanoparticles
PublikacjaComposite photocatalysts that consist of TiO2and noble metal nanostructures have been considered tobe the promising and pivotal material for accessible enhancement of the efficiency in the photocatalyticprocess carried out in the aqueous and gas phases. In this work we fabricated porous TiO2microspheresthrough a hydrothermal process followed by photochemical reduction of noble metal nanoparticles atthe TiO2surface. The morphology...
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Prediction of metal deformation due to line heating; an alternative method of mechanical bending, based on artificial neural network approach
PublikacjaLine heating is one of the alternative methods of forming metals and this kind of forming uses the heating torch as a source of heat input. During the process, many parameters are considered like the size of the substrate, thickness, cooling method, source power intensity, the travel speed of the power source, the sequence of heating, and so on. It is important to analyze the factors affecting the...
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The Effect of Welding Conditions on Diffusible Hydrogen Content in Deposited Metal
PublikacjaThe article presents the results of a literature survey and preliminary tests which set out effects of welding conditions on the amount of diffusible hydrogen in deposited metal. Experiments were conducted by using rutile coated electrodes which generate high contents of diffusible hydrogen in deposited metal. The amount of diffusible hydrogen was determined by a glycerin test.Eleven factors were considered: the electrode angle,...
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A first-principles study of electronic and magnetic properties of 4d transition metals doped in Wurtzite GaN for spintronics applications
PublikacjaWe studied the electronic and magnetic properties of wurtzite GaN (w-GaN) doped with different concentrations of the 4d transition metal ions Nb, Mo, and Ru. We incorporated spin-polarized plane-wave density functional theory within an ultrasoft pseudopotential formalism. The 4d transition metals were doped at different geometrical sites to determine the geometry with the lowest total energy and the one that induced the largest...
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Effect of underwater wet welding conditions on the diffusible hydrogen content in deposited metal
PublikacjaIn the study mercury displacement method was used for determination of diffusible hydrogen amount in deposited metal obtained during underwater wet welding with covered electrodes in laboratory conditions according to a two-level full factorial design for three factors. The factors and their levels were chosen among conditions and parameters of welding in accordance with the results of own preliminary studies. A statistical analysis...
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Phosphoroorganic Metal Complexes in Therapeutics
PublikacjaThe present mini-review highlights recent developments on antitumor activity of metal-based therapeutics which have been a subject of researches for the last few decades. In 1965, Rosenberg found that during an electrolysis on platinum electrodes a complex of Pt is generated which inhibited to a great extent a binary fission in Escherichia coli bacteria. This discovery started a new chapter in medicinal chemistry and the interesting...
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Laser Dissimilar Welding of AISI 430F and AISI 304 Stainless Steels
PublikacjaA dissimilar autogenous laser welded joint of AISI 430F (X12CrMoS17) martensitic stainless steel and AISI 304 (X5CrNi18-10) austenitic stainless steel was manufactured. The welded joint was examined by non-destructive visual testing and destructive testing by macro- and microscopic examination and hardness measurements. With reference to the ISO 13919-1 standard the welded joint was characterized by C level, due to the gas pores...
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Effect of the welding environment and storage time of electrodes on the diffusible hydrogen content in deposited metal
PublikacjaIn the study the glycerin displacement method was used for determination of diffusible hydrogen content in deposited metal. Specimens were welded in the air and in the water with covered rutile electrodes. The first part of the specimens was made immediately after opening the package of the electrodes. The electrodes were then stored in opened packages in laboratory conditions that allowed for contact with the air for three years....
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Catalytic Mechanism of Non-Target DNA Cleavage in CRISPR-Cas9 Revealed by Ab Initio Molecular Dynamics
PublikacjaCRISPR-Cas9 is a cutting-edge genome editing technology, which uses the endonuclease Cas9 to introduce mutations at desired sites of the genome. This revolutionary tool is promising to treat a myriad of human genetic diseases. Nevertheless, the molecular basis of DNA cleavage, which is a fundamental step for genome editing, has not been established. Here, quantum–classical molecular dynamics (MD) and free energy methods are used...
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Metallurgical characterization and high-temperature tensile failure of Inconel 617 alloy welded by GTAW and SMAW—a comparative study
PublikacjaTwo types of the weld joint of Inconel 617 alloy were produced using gas tungsten arc welding (GTAW) and shielded metal arc welding (SMAW) processes with ERNiCrCoMo-1 filler metal and ENiCrCoMo-1 electrode, respectively. The weld metal showed the segregation of the principle alloying elements like Mo and Cr along the inter-dendritic spaces, triggering the formation of secondary phases. The microstructure characterization of the...
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Insulator to correlated metal transition in V1−xMoxO2
PublikacjaDyskutowane jest przejście typu izolatro - metal w domieszkowanym atomami Molibdenu związku V1-xMoxO2. Prezentowany jest diagram fazowy.