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Search results for: METAL-ORGANIC FRAMEWORKSOPEN METAL SITESCATALYSISHYDROGENATION4-NITROPHENOL
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Experimental research of the stability of steel cylindricalshell subjected to circumferential compression
PublicationAt the Department of Metal Structures Gdańsk University of Technology, experiments have been performed on the stability of shell of steel cylindrical models. The experiments have been carried on a test bench built at the Department. The design based on other test benches which were created in the past by other scientists, where modernized by the courtesy of companies that offer modern solutions. The test bench enables to generate...
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Lower rim substituted p-tert-butylcalix[4]arene; Part 14. Synthesis, structures and binding studies of calix[4]arene thioamides
PublicationA number of p-tert-butylcalix[4]arene thioamides were synthesized and characterized by 1H-NMR and elemental analysis. Compounds 1-5 are O-substituted derivatives with -CH2-C(=S)-N-X groups, where NX = morpholidyl, NEt2, NHC2H4Ph, NHCH2Ph and NHEt,respectively. The X-ray structures of the ligands 1, 3, 5 and of the complex 3Pb(ClO4)2, (compound 6), are presented and their slightly distorted cone conformation is established. The...
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Ion recognition properties of new pyridine-2,6-dicarboxamide bearing propeller-like pendant residues: multi-spectroscopic approach
PublicationThe synthesis and ion binding properties of new amide derived from propeller-like tris(2-pyridyl)amine and 2,6-pyridinedicarboxylic acid chloride were described. Amide binds divalent metal cations: copper(II), nickel(II), zinc(II), and lead(II) in acetonitrile. In acetonitrile:water mixture (9:1 v/v) amide interacts only with copper(II) and nickel(II) cations forming complexes of 1:1 stoichiometry. It was found that the introduction...
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EVALUATION OF THE NO2CONCENTRATION PREDICTION POSSIBILITYBASED ON STATIC AND DYNAMIC RESPONSES OF TGS SENSORSAT CHANGING HUMIDITY LEVELS
PublicationThe commercially available metal-oxide TGS sensors are widely used in many applications due to thefact that they are inexpensive and considered to be reliable. However, they are partially selective and theirresponses are influenced by various factors,e.g. temperature or humidity level. Therefore, it is importanttodesign a proper analysis system of the sensor responses. In this paper, the results of examinations of eightcommercial...
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Simultaneous Removal of Al, Cu and Zn Ions from Aqueous Solutions Using Ion and Precipitate Flotation Methods
PublicationThis paper presents the results of investigations concerning the simultaneous removal of Al(III), Cu(II), and Zn(II) from dilute aqueous solutions using ion and precipitate flotation methods. The effects of initial solution pH, surface active substance concentration, and the gas velocity on the flotations’ efficiency and course are studied. Experimental results are discussed in terms of physicochemical aspects related to aqueous...
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Prediction of the fatigue lifetime of PUR structural elements using a combined experimental-numerical approach
PublicationThis paper presents a method for estimating the fatigue life of polyurethane elastomeric components. A rubber replacement - polyurethane of hardness 80ShA commonly used in vibration damping systems, for example, in motor vehicle suspensions, was used for the study. A metal-rubber bushing component was selected for analysis, and numerical analysis was carried out along with a fatigue model proposal based on a modification of the...
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The influence of the carbon equivalent on the weldability of high-strength low-alloy steel in the water environment
PublicationFrom many years, the high strength low alloy steels are often used for offshore constructions. This constructions, due to the environment in which they work, require more frequent repairs than the constructions from the land. For economic reasons, repairs take place in the underwater conditions, however water significantly decreases the weldability of steel. The paper presents the results of the CTS weldability test for S460ML...
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Excited state properties of a series of molecular photocatalysts investigated by time dependent density functional theory.
PublicationTime dependent density functional theory calculations are applied on a series of molecular photocatalysts of the type [(tbbpy)2M1(tpphz)M2X2]2+ (M1 = Ru, Os; M2 = Pd, Pt; X = Cl, I) in order to provide information concerning the photochemistry occurring upon excitation of the compounds in the visible region. To this aim, the energies, oscillator strengths and orbital characters of the singlet and triplet excited states are investigated....
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Superconductivity on a Bi Square Net in LiBi
PublicationWe present the crystallographic analysis, superconducting characterization and theoretical modeling of LiBi, that contains the lightest and the heaviest nonradioactive metal. The compound crystallizes in a tetragonal (CuAu-type) crystal structure with Bi square nets separated by Li planes (parameters a = 3.3636(1)Å and c = 4.2459(2) Å, c/a = 1.26). Superconducting state was studied in detail by magnetic susceptibility and heat...
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MULTI-CRITERIA COMPARATIVE ANALYSIS OF THE USE OF SUBTRACTIVE AND ADDITIVE TECHNOLOGIES IN THE MANUFACTURING OF OFFSHORE MACHINERY COMPONENTS
PublicationThe dynamic development of additive manufacturing technologies, especially over the last few years, has increased the range of possible industrial applications of 3D printed elements. This is a consequence of the distinct advantages of additive techniques, which include the possibility of improving the mechanical strength of products and shortening lead times. Offshore industry is one of these promising areas for the application...
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Influence of Protonation State on the Excited State Dynamics of a Photobiologically Active Ru(II) Dyad
PublicationThe influence of ligand protonation on the photophysics of a ruthenium (Ru) dyad bearing the 2-(1-pyrenyl)-1H-imidazo[4,5-f][1,10]-phenanthroline (ippy) ligand was investigated by time-resolved transient absorption spectroscopy. It was found that changes in the protonation state of the imidazole group led to changes in the electronic configuration of the lowest lying excited state. Formation of the fully deprotonated imidazole...
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Development of dynamic method for evaluation of inhibition efficiency on the example of 8-hydroxyquinolin
PublicationSelection of a proper inhibitor should be based on the evaluation of its mechanism and effective concentrations. Mechanism of inhibition usually has dynamic character due to changing physicochemical conditions of the environment and corroding metal surface. Most of actually used methods are stationary or contain assumptions which highly influences obtained values. Development of new dynamic method, based on modified EIS, allows...
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A simplified behavioral MOSFET model based on parameters extraction for circuit simulations.
PublicationThe paper presents results on behavior modeling of general purpose Metal-Oxide Semiconductor Field-Effect Transistor (MOSFET) for simulation of power electronics systems requiring accuracy both in steady-state and in switching conditions. Methods of parameters extraction including nonlinearity of parasitic capacitances and steady-state characteristics are based on manufacturer data sheet and externally measurable characteristics....
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RESIDUE ANALYSIS OF ETU AND PTU BY LC/MS
PublicationDithiocarbamates (DTCs) are important organosulfur compounds, which act as inhibitors of metal dependant and sulphydryl enzymes and have a serious consequence on biological systems. They possess variety of applications in agriculture as fungicides, as well as, in the rubber industry as vulcanization accelerators and antioxidants. In this way, DTCs are the main group of fungicides used to control approximately 400 pathogens of more...
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Effect of heat treatment on the diffusion intermixing and structure of the Cu thin film on Si (111) substrate: a molecular dynamics simulation study
PublicationThis work is devoted to the study of the diffusion process at the interface between copper films with a thickness of 2, 3, 4, 7 and 10 atomic monolayers and silicon substrate by molecular dynamics simulation method. For this purpose, the variation of the concentration of copper and silicon along the perpendicular direction to the interface was investigated. An analysis of the density profile along this direction made it possible...
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Novel Diazocrowns with Pyrrole Residue as Lead(II) Colorimetric Probes
PublicationNovel 18- and 23-membered diazomacrocycles were obtained with satisfactory yields by diazocoupling of aromatic diamines with pyrrole in reactions carried under high dilution conditions. X-ray structure of macrocycle bearing five carbon atoms linkage was determined and described. Compounds were characterized as chromogenic heavy metal ions receptors. Selective color and spectral response for lead(II) was found in acetonitrile and...
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Activated Tungsten Inert Gas Weld Characteristics of P91 Joint for Advanced Ultra Supercritical Power Plant Applications
PublicationActivated Tungsten Inert Gas (A-TIG) welding, a variant of tungsten inert gas (TIG) welding, was used for welding P91. In Generation IV power plants, P91 welds are prone to premature failure due to the presence and formation of brittle phases and creep at high temperatures. When performing A-TIG welding, the flux composition plays a role in the reversal of the Marangoni flow in the weld pool, which ultimately determines the level...
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Underwater wet welding of S1300 ultra-high strength steel
PublicationMarine Structures Volume 81, January 2022, 103120 Underwater wet welding of S1300 ultra-high strength steel Author links open overlay panelJacekTomkówGrzegorzRogalski https://doi.org/10.1016/j.marstruc.2021.103120 Get rights and content Under a Creative Commons licenseopen access Highlights • Technological method of S1300 steel underwater weldability improving was proposed. • Number of cracks and hardness of welded joints was...
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Development of a vortex-assisted switchable-hydrophilicity solvent-based liquid phase microextraction for fast and reliable extraction of Zn (II), Fe (II), Pb (II), and Cd (II) from various baby food products
PublicationThis manuscript describes the development of a novel liquid phase microextraction (LPME) method for the extraction and determination of Zn (II), Fe (II), Pb (II), and Cd (II) in various infant/baby food and supplements products. The method is based on vortex-assisted extraction combined with a switchable-hydrophilicity solvent (SHS) sample preparation. The SHS, which undergoes reversible phase changes triggered by pH change, enables...
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Mission impossible for cellular internalization: When porphyrin alliance with UiO-66-NH2 MOF gives the cell lines a ride
PublicationIs it possible to accelerate cell internalization by hybridization of nanomaterials? Herein we support the realization of using metal-organic frameworks (MOFs) with the assistance of rigid porphyrin structure (H2TMP) aimed at drug loading, drug release, relative cell viability, and targeted in vitro drug delivery. There are several MOFs, i.e., UiO-66-NH2 (125 ± 12.5 nm), UiO-66-NH2 @H2TMP (160 ± 14 nm), UiO-66-NH2 @H2TMP@DOX, and...
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Can bottom sediments be a prospective fertilizing material? A chemical composition analysis for potential reuse in agriculture.
PublicationEvery year huge amounts of bottom sediments are extracted worldwide, which need to be dis-posed. The recycling of bottom sediments for soil fertilization is in line with the long-promoted circular economy policy and enables the use of micro and macronutrients accumulated in sedi-ments for soil fertilization. When considering potential agricultural reuse of the dredge sediments, the first necessary step should be to analyze whether...
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Badania nośności na zginanie innowacyjnego kształtownika giętego na zimno typu GEB
PublicationLekkie konstrukcje metalowe wytwarzane z kształtowników giętych na zimno to jedna z najszybciej rozwijających się dyscyplin w zakresie budownictwa. Do niedawna profile gięte na zimno stosowano wyłącznie jako elementy drugorzędne, czyli płatwie oraz rygle. Nowo opatentowany przekrój typu GEB ma być wykorzystywany jako element nośny konstrukcji ramowych. Jednak jego zaistnienie na rynku budowlanych konstrukcji metalowych jest uwarunkowane...
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Dirac fermions and possible weak antilocalization in LaCuSb2
PublicationLayered heavy-metal square-lattice compounds have recently emerged as potential Dirac fermion materials due to bonding within those sublattices. We report quantum transport and spectroscopic data on the layered Sb square-lattice material LaCuSb2. Linearly dispersing band crossings, necessary to generate Dirac fermions, are experimentally observed in the electronic band structure observed using angle-resolved photoemission spectroscopy,...
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Phytoremediation—From Environment Cleaning to Energy Generation—Current Status and Future Perspectives
Publication:Phytoremediationis a technology based on the use of green plants to remove, relocate, deactivate, or destroy harmful environmental pollutants such as heavy metals, radionuclides, hydrocarbons, and pharmaceuticals. Under the general term of phytoremediation, several processes with distinctively different mechanisms of action are hidden. In this paper, the most popular modes of phytoremediation are described and discussed. A broad...
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Does the low optical band gap of yellow Bi3YO6 guarantee the photocatalytical activity under visible light illumination?
PublicationBi3YO6, which is known as an ionic conductor, was tested here as an electrode and photoanode in contact with aqueous electrolytes. Bi3YO6 was deposited onto the Pt substrate and the such prepared electrode was polarized in various aqueous electrolytes. The optical energy band gap of the material equal to 1.89 eV was determined using the Kubelka-Munk function resulting from the UV-Vis spectrum (allowed indirect transition) and also...
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KTaO3 a perovskite for water and air treatment
PublicationPerovskites are inorganic compounds that exhibit dielectric properties. These minerals belong to the crystal ceramics family. These compounds are described by the formula: ABX3 where, A and B are 2, 3 or 4 valuable metal ions, and X is an ion of oxygen or fluorine. An example of perovskite is the compound KTaO3. There are many methods for producing KTaO3, but the hydrothermal method is most commonly used. Perovskites can be characterized...
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COMPARATIVE NUMERICAL ANALYSIS OF DIFFERENT STRENGTHENING SYSTEMS OF HISTORICAL BRICK ARCHES
PublicationThe article presents a comparative numerical analysis of various ways to strengthen historical brick arches. Five ways of strengthening brick arches with steel tie-rods have been proposed. Two of these involve the use of braces wrapped around pillars supporting the arch connected with a tie-rod; another two ways involve the use of the tie-rods with welded metal sheets of different sizes; the last way involves the use of the tie-rod...
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APPLICATION OF MAGNETIC NANOPARTICLES FOR WATER TREATMENT
PublicationIn this study magnetic nanoparticles were fabricated and used for water treatment. Nanoparticles were prepared in two ways. The first one involved NiZn ferrite nanoparticles synthesized by co-precipitation of metal cations with sodium hydroxide at high temperature. The second one featured maghemite nanoparticles was prepared by saltassisted solid-state reaction. Modification and functionalization of nanoparticles surface was investigated....
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1,3,4-Thiadiazole-based diamides: Synthesis and complexation properties
PublicationAromatic diamides, derivative of 2,6-pyridinedicarboxylic acid and isophthalic acid, bearing 1,3,4-thiadiazole residue were prepared with satisfactory yields in conventional procedures and microwave stimulated reactions. X-ray structure of N,N-bis (1,3,4-thiadiazol-2-yl)-2,6-pyridinedicarboxamide (2) DMSO solvate (2DMSO) was described. Selective zinc(II), lanthanum(III), terbium(III) and L-tyrosine recognition was found for N,N-bis(1,3,4-thiadiazol-2-yl)-2,6-pyridinedicarboxamide...
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Electrolytic corrosion of water pipeline system in the remote distance from stray currents– case study
PublicationCase study of corrosion failure of urban water supply system caused by the harmful effects of stray currents was presented. The failure occurred at a site distant from the sources of these currents namely the tramway and railway traction systems. Diagnosis revealed the stray currents flow to pipeline over a remote distance of 800 ÷ 1,000 meters from the point of failure. At the point of failure stray currents flowed from the pipeline...
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3D Sound Intensity Measurement Around Organ Pipes Using Acoustic Vector Sensors
PublicationThe aim of the presented paper was to obtain and visualize sound intensity distribution of radiated acoustic energy around the organ pipes. The experimental setup consisted of the multichannel acoustic vector sensor and the specialized Cartesian robot. Measurements were performed in free field with spatial resolution of 0.1 [m]. Two organ pipes, i.e. wooden and metal were measured during the ex-periment. The organ pipes were activated...
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High temperature corrosion resistance of porous hastelloy alloy
PublicationTo further understand the suitability of Ni-Cr-base alloy for solid oxide fuel cell (SOFC), a commercial Ni-Cr-Fe-Mo alloy, Hastelloy X was selected and evaluated for oxidation behaviour under high temperature conditions. HastelloyX was chosen due to its unusual resistance to oxidizing, reducing and neutral atmospheres. For long term stability of metal supported fuel cell, the corrosion resistance plays a vital role and must be...
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On the necessity of experimental verification of numerical results in biomedical applications
PublicationPorous structures made of metal or biopolymers with a structure similar in shape and mechanical properties to human bone can be easily produced by stereolitography techniques, e.g. selective laser melting (SLM). Numerical techniques, like finite element method (FEM) have great potential in testing new, even the most sophisticated designs, according to their mechanical properties, i.e. strength or stiffness. However, due to different...
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Microfluidic devices for photo-and spectroelectrochemical applications
PublicationThe review presents recent developments in electrochemical devices for photo- and spectroelectrochemical investigations, with the emphasis on miniaturization (i.e., nanointerdigitated complementary metal-oxide-semiconductor devices, micro- and nano-porous silicon membranes or microoptoelectromechanical systems), silica glass/microreactors (i.e., plasmonic, Raman spectroscopy or optical microcavities) or polymer-based devices (i.e.,...
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Shape Memory Materials from Rubbers
PublicationSmart materials are much discussed in the current research scenario. The shape memory effect is one of the most fascinating occurrences in smart materials, both in terms of the phenomenon and its applications. Many metal alloys and polymers exhibit the shape memory effect (SME). Shape memory properties of elastomers, such as rubbers, polyurethanes, and other elastomers, are discussed in depth in this paper. The theory, factors...
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A Comprehensive Experimental and Theoretical Study on the[{(η5-C5H5)2Zr[P(µ-PNEt2)2P(NEt2)2P]}2O Crystalline System
PublicationThe structure of tetraphosphetane zirconium complex C52H100N8OP10Zr21 was determined by single crystal X-ray diffraction analysis. The crystal belongs to the monoclinic system, space group P21/c, with a = 19.6452(14), b = 17.8701(12), c = 20.7963(14)Å, α = γ = 90°, β = 112.953(7)°, V = 6722.7(8)Å3, Z = 4. The electronic structure of the organometallic complex has been characterized within the framework of Quantum Chemical Topology....
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Miniaturized Dual-Band SIW-Based Bandpass Filters Using Open-Loop Ring Resonators
PublicationThis article presents two novel architectures of dual-band substrate integrated waveguide (SIW) bandpass filters (BPFs). Initially, two identical open-loop ring resonators (OLRRs) are coupled face-to-face on the top of the SIW cavity to realize a dual-band single-pole BPF. To obtain two-pole dual-band characteristics, two OLRRs resonant units are assembled horizontally within the top metal layer of the SIW, which is a technique...
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Chromogenic azomacrocycles with imidazole residue: Structure vs. properties
PublicationNew diazo macrocycles linked by hydrocarbon chain bearing imidazole or 4-methylimidazole residue have been synthetized with satisfactory yield (24–55%). The structure of macrocycles was confirmed by X-ray analysis and spectroscopic methods (1H NMR, MS, FTIR). Metal cation complexation studies were carried out in acetonitrile and acetonitrile-water system. It was found that azomacrocyles form triple-decker complexes with lead(II)....
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Dynamic analysis of temporary steel grandstand equipped with different types of bracing system
PublicationIn the paper, behaviour of a temporary steel grandstand equipped with two different types of bracing system has been analysed through the numerical study. A typical solution concerning application of a diagonal tubular members has been compared with elements proposed by authors and called polymer dampers. A polymer element consists of two L-shape steel members bonded with polymer mass. The aim of the paper is to verify the effectiveness...
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Experimental research on marine oil-lubricated stern tube bearing
PublicationBearings of propeller shafts are very crucial elements of the propulsion system of each of the ships. The safety of shipping depends on their durability and reliability. The new legal restrictions mean that today we are looking for environmentally friendly solutions. That is why water-lubricated bearings are becoming more and more popular. So, will oil-lubricated shaft bearings belong to the past? The bearing with a white metal...
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Cyclic mechanical stress impact on protective properties of organic coatings
PublicationCelem pracy jest zaprezentowanie wyników badań wpływu cyklicznych naprężeń mechanicznych na układy powłoka/metal. Powtarzające się naprężenia mechaniczne zostały zidentyfikowane jako czynnik w znaczącym stopniu przyczyniający się do degradacji powłok. Próbki składające się z powłoki epoksydowej nałożonej na stal St3SAl poddano serii 21000 cykli naprężenie-odpuszczenie. Badania przeprowadzono w zakresie odkształceń elastycznych...
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Similarities and differences in d6 low-spin ruthenium, rhodium and iridium half-sandwich complexes: synthesis, structure, cytotoxicity and interaction with biological targets
PublicationIn this paper, we discussed the similarities and diferences in d6 low-spin half-sandwich ruthenium, rhodium and iridium complexes containing 2,2′-biimidazole (H2biim). Three new complexes, {[RuCl(H2biim)(η6 -p-cymene)]PF6}2·H2O (1), [(η5 - Cp)RhCl(H2biim)]PF6 (2), and [(η5 -Cp)IrCl(H2biim)]PF6 (3), were fully characterized by CHN, X-ray difraction analysis, UV–Vis, FTIR, and 1 H, 13C and 15N NMR spectroscopies. The complexes exhibit...
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Li nucleation on the graphite anode under potential control in Li-ion batteries
PublicationApplication of Li-ion batteries in electric vehicles requires improved safety, increased lifetime and high charging rates. One of the most commonly used intercalation anode material for Li-ion batteries, graphite, is vulnerable to Li nucleation, a side reaction which competes with the intercalation process and leads to loss of reversible capacity of the battery, ageing and short-circuits. In this study, we deploy a combined grand...
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Conducting polymers for biodegradable metallic implants
PublicationNowadays permanent metallic cardiovascular stents are long-term implants. The long-time presence of such an implant in human body can cause overgrowth of tissue within the treated portion of the vessel, blockage of the circulatory system and many other clinical complications, such as thrombosis, prolonged physical irritations or chronic inflammation. Therefore, in recent years, there is an interest to create biodegradable metallic...
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The first compound with an unusual type of anion, [Li(SR)2]-:bis(µ2-aqua-d2)tetrakis(aqua-d2)]dilithium(I)bis[bis(tri-tert-butoxysilanethiolato-k2O,S)lithate(I)]dihydrate-d2
PublicationTytułowy związek [Li2(D2O)6][Li(C9H27SSiO3)2]2*2D2O, jest pierwszym związkiem z wiązaniem S-M (M-metal alkaliczny), zawierającym niespotykany typ anionu litanowego: [Li(SR)2]-,gdzie R=Si{OC{CH3)3}3. Centrum symetrii związku znajduję się pośrodku pierścienia Li2O2 wchodzącego w skład kationu. Wszystkie atomy litu budujące rdzenie kationów - LiO4 i anionów - LiO2S2, są czterokoordynacyjne. Jednoujemne aniony [Li(SR)2]- są dobrze...
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Construction of glucosamine-6-phosphate synthase with an internal hexahistydyl fragment
PublicationL-Glutamine: D-fructose-6-phosphate aminotransferase (EC 2.6.1.16), known also as glucosamine-6-phosphate (GlcN-6-P) syntase, catalyzes the first committed step in the amino sugar biosynthetic pathway in prokaryotic and eukaryotic organisms. The enzyme carries out a complex reaction involving ammonia transfer and sugar phosphate isomerization. GlcN-6-P syntase is an important point of metabolic control of amino sugar biosynthesis...
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Optical recognition elements: macrocyclic imidazole chromoionophores entrapped in silica xerogel
PublicationMaterials containing new chromoionophores consisting of crown residue and azole moiety as partsof macrocycles were encapsulated by the sol-gel procedure in silica xerogel matrices and proposed aschemical recognition elements especially for such metal ions as Li+, Cs+ and Cu2+. Action of these recognition elements is in principle based on changes of reflectance. The recognition elements containing 21-membered chromogenic...
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Advances in mass spectrometry for iron speciation in plants
PublicationIron is an important nutrient essential for plants and critical for human health. The state-of-the art of methods for iron speciation in cereal grains and plant fluids is critically reviewed. Particular attention is given to the latest developments in the coupling of HPLC with the parallel ICP MS and electrospray ionization (ESI) MS/MS detection, usually QTOF MS or Q-Orbitrap MS, for the identification and quantification of iron...
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La 15 Nb x Ge 9 : a superstructure of the Mn 5 Si 3 structure type with interstitial Nb atoms
PublicationThe crystal structure and elementary properties of La15NbxGe9 are reported. Single-crystal X-ray diffraction,from a crystallite with only 0.12 Nb/formula unit, reveals that this compound, although transition metal deficient, crystallizes in a hexagonal “15-1-9”-like structure type, space group P63mc (no. 186) with lattice parameters a = b = 15.5017(2) Å, c = 6.9173(2) Å. The physical properties were examined by specific heat and resistivity...
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White cabbage in the biofumigation process- expectations and perspectives
PublicationHealth risks related to common use of pesticides and artificial fertilizers raised the interest in alteranative methods of crop protection, among them biofumigation is becoming the most promising. In this process certain natural compounds, mainly degradation products of glucosinolates produced by Brassica species are used to combat pests and microorganisms attacking crops. Increased synthesis of these bioactive compounds can be...