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The chemical and mechanical pressure influence on chromium luminescence
Dane BadawczeIn this study, we aim to compare the changes in the luminescence properties of Ga2O3:Cr3+ modified by Al or Sc ion substitution (chemical pressure) and hydrostatic pressure. We find the same behavior for Ga2–xAlxO3:Cr3+ and different behavior for Ga2–xScxO3:Cr3+ in terms of the optical properties under chemical and mechanical pressure. We consider Al...
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Corrosion behavior of concrete produced with diatomite and zeolite exposed to chlorides
PublikacjaChloride induced reinforcement corrosion is widely accepted to be the most frequent mechanism causing premature degradation of reinforced concrete structures. The electrochemical impedance of reinforcing steel in diatomite- and zeolite-containing concrete exposed to sodium chloride was assessed. Chemical, physical and mineralogical properties of three concrete samples (20% diatomite, 20% zeolite, and a reference containing neither)...
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Displacements of bones during bending test of first metatarsophalangeal joint after arthrodesis with medially or dorsally positioned locking plate and lag screw.
Dane BadawczeThe Dataset contains the values of displacements of bone control points during the bending test of first metatarsophalangeal (MTP1) joint specimens after arthrodesis.
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Surface Texture after Turning for Various Workpiece Rigidities
PublikacjaIn the paper, we present an analysis of the surface texture of turned parts with L/D (length/diameter) ratios of 6 and 12 and various rigidity values. The studies were carried out on samples made of S355JR steel and AISI 304 stainless steel. A detailed analysis of 2D surface profiles was carried out by using a large number of parameters that allowed us to distinguish significant differences in the surface microgeometry, which confirmed...
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INFLUENCE OF TACK WELDS DISTRIBUTION AND WELDING SEQUENCE ON THE ANGULAR DISTORTION OF TIG WELDED JOINT
PublikacjaIn this paper the influence of tack welds distribution and welding sequence on angular distortion of the Tungsten Inert Gas (TIG) welded joint was tested. Additionally, the effect of welding current on angular distortion was assessed. For research X2CrTiNb18 (AISI 441) stainless steel (2.5 mm thick) was chosen. During research specimens were prepared with different distributionsof tack...
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Effect of electrode waterproof coating on quality of underwater wet welded joints
PublikacjaIn this paper, the effects of different hydrophobic coatings on the surface of covered electrodes on the quality of wet welded carbon steel joints were discussed. Commonly available hydrophobic substances used in industrial applications were selected for the research. The aim of using waterproof coatings was to check the possibility to decreasing the susceptibility of highstrength low-alloy S460N steel to cold cracking. During...
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Ship’s de-perming process using coils lying on seabed
PublikacjaA ship built from ferromagnetic steel disturbs the uniformity of the Earth’s magnetic field. Changes of ship’s signature are due to the magneto-mechanical interaction of the hull with the Earth’s magnetic field. The ship’s magnetic field can be detected by a magnetic naval mine. For this reason, the vessel has to be demagnetized. There are several methods of ship’s de-perming. The results of experimental and computer simulations...
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Reference-free determination of debonding length in reinforced concrete beams using guided wave propagation
PublikacjaThis paper presents theoretical and experimental investigations of guided wave propagation in reinforced concrete beams, with pre-existing debonding between steel rebars and concrete blocks, for the purpose of damage detection. The primary aim of these investigations was a detailed analysis of the possible applications of wave propagation in single and multiple debonding detection in reinforced concrete structures and reference-free...
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Numerical investigation of the core eccentricity effect on wave propagation in embedded waveguide
PublikacjaThe paper presents results of theoretical and numerical investigation of guided wave propagation in two-layer bars with geometric imperfections in the form of eccentric location of steel core. Steel rod of diameter equal to 1 cm embedded in composite mortar-type cover with external diameter equal to 5 cm has been taken into consideration. Several different rods with variable size of eccentricity are analysed. Results for rods with...
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Study of Integer Spin S = 1 in the Polar Magnet β-Ni(IO3)2
PublikacjaPolar magnetic materials exhibiting appreciable asymmetric exchange interactions can potentially host new topological states of matter such as vortex-like spin textures; however, realizations have been mostly limited to half-integer spins due to rare numbers of integer spin systems with broken spatial inversion lattice symmetries. Here, we studied the structure and magnetic properties of the S = 1 integer spin polar magnet β-Ni(IO3)2...
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Repeated Projectile Impact Tests on Multi-Layered FibrousCementitious Composites
PublikacjaThis research aims to experimentally evaluate the behaviour of multi-layered fibrous cementitious composites withintermediate Glass Fibre Meshes (GFM) under repeated projectile load. The impact load was subjected through a convexedge projectile needle at a low velocity on cylindrical specimens of three-layered fibrous cementitious composites, whichhave two different steel fibre distributions. In series A mixtures, a constant steel...
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Building damage due to structural pounding during earthquakes
PublikacjaEarthquake-induced pounding between adjacent buildings has been identified as one of the reasons for substantial damage or even total collapse of colliding structures. A major reason leading to interactions in buildings results from the differences in their dynamic parameters and also from insufficient distance between the structures. Although the research on structural pounding has been much advanced, the studies have mainly been...
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SiC coating in ring-on-ring sliding with saline solution (0.9%) lubrication 5MPa, 0.1m/s specimn. #B37/#A35
Dane BadawczeWear tests in sliding friction of SiC coating on 1.4021 (EN 10088-1) heat treated stainless steel. Ring - on - ring contact in unidirectional sliding, SiC over SiC . Mean contact stress: 5MPa. Sliding velocity: 0,1 m/s. Mean friction radius: 9.5mm. Lubricant: SALINE SOLUTION (0.9%). Tribometer: PT-3. Overall test time till coating penetration 3 min.Secimen...
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TiC coating in ring-on-ring sliding with saline solution (0.9%) lubrication 5MPa, 0.1m/s specimn. #A39/#B41
Dane BadawczeWear tests in sliding friction of TiC coating on 1.4021 (EN 10088-1) heat treated stainless steel. Ring - on - ring contact in unidirectional sliding, TiC over TiC . Mean contact stress: 5MPa. Sliding velocity: 0,1 m/s. Mean friction radius: 9.5mm. Lubricant: SALINE SOLUTION (0.9%). Tribometer: PT-3. Overall test time till coating penetration 3 min.Secimen...
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SiC coating in ring-on-ring sliding with saline solution (0.9%) lubrication 5MPa, 0.1m/s specimn. #A35/#B37
Dane BadawczeWear tests in sliding friction of SiC coating on 1.4021 (EN 10088-1) heat treated stainless steel. Ring - on - ring contact in unidirectional sliding, SiC over SiC . Mean contact stress: 5MPa. Sliding velocity: 0,1 m/s. Mean friction radius: 9.5mm. Lubricant: SALINE SOLUTION (0.9%). Tribometer: PT-3. Overall test time till coating penetration 3 min.Secimen...
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Effects of V2O5 Additive on Structure and Dielectric Properties of BiNbO4 Ceramics
PublikacjaGoal of the present research was to investigate the influence of V2O5 additive on the structure and dielectric properties of BiNbO4 ceramics. To fabricate BiNbO4 ceramics with V2O5 added the solid state reaction route and pressureless sintering was utilized. Thus obtained ceramics was characterized in terms of its microstructure (SEM), chemical composition (EDS), phase composition and crystalline structure (X-ray phase and structural...
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Charge density wave and large nonsaturating magnetoresistance in YNiC2 and LuNiC2
PublikacjaWe report a study of physical properties of two quasi-low-dimensional metals YNiC2 and LuNiC2 including the investigation of transport, magnetotransport, galvanomagnetic, and specific heat properties. In YNiC2 we reveal two subsequent transitions associated with the formation of weakly coupled charge density wave at TCDW=318K and its locking in with the lattice at T1=275K. These characteristic temperatures follow the previously...
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La 15 Nb x Ge 9 : a superstructure of the Mn 5 Si 3 structure type with interstitial Nb atoms
PublikacjaThe 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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Transparent thin films of Cu-TiO2 with visible light photocatalytic acitivity
PublikacjaThin films of Cu–TiO2 with a high level of transparency were prepared by a dip-coating procedure on the glass surface. CuCl2 was used as a copper precursor added during sol – gel synthesis of TiO2. The extension of optical absorption into the visible region of as-prepared thin films was indicated by UV/Vis spectroscopy. Only the anatase phase was detected by X-ray di ffraction analysis (XRD). The presence of copper in the structure...
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Crystal structure and physical properties of new Ca2TGe3 (T = Pd and Pt) germanides
PublikacjaThe crystallographic, electronic transport and thermal properties of Ca2PdGe3 and Ca2PtGe3 are reported. The compounds crystalize in an ordered variant of the AlB2 crystal structure, in space group P6/mmm, with the lattice parameters a = 8.4876(4) Å/8.4503(5) Å and c = 4.1911(3) Å/4.2302(3) Å for Ca2PdGe3 and Ca2PtGe3, respectively. The resistivity data exhibit metallic behavior with residual-resistivity-ratios (RRR) of 13 for...
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MgPdSb─An Electron-Deficient Half-Heusler Phase
PublikacjaThe half-Heusler family consists of many semiconducting intermetallic compounds, virtually all of them having a valence electron count (VEC) of 18. We have studied an electron-deficient (VEC = 17) phase MgPdSb and its Pd-stuffed variant MgPd1.25Sb. The cubic F4̅3m crystal structure was confirmed by the Rietveld refinement of powder X-ray diffraction (XRD) data. The lattice parameter is a = 6.284 and 6.335 Å for MgPdSb and MgPd1.25Sb,...
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Strong-coupling superconductivity of SrIr2 and SrRh2 : Phonon engineering of metallic Ir and Rh
PublikacjaExperimental and theoretical studies on superconductivity in SrIr2 and SrRh2 Laves phases are presented. The measured resistivity, heat capacity, and magnetic susceptibility confirm the superconductivity of these compounds with Tc = 6.07 and 5.41 K, respectively. Electronic structure calculations show that the Fermi surface is mostly contributed by 5d (4d) electrons of Ir (Rh), with Sr atoms playing the role of electron donors....
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Structure and transport properties of donor-doped barium strontium cobaltites
PublikacjaIn this work, Nb-substituted barium strontium cobaltites Ba0.5Sr0.5Co1-xNbxO3-δ (x = 0 – 0.4) have been fabricated and studied. The structural analysis showed that the Nb content influences the lattice constant as well as the distance between the (Co, Nb) and oxygen atoms. The study of morphology of samples showed that the Nb content does not change the porosity, grain size and morphology of the ceramics. The total electrical conductivity...
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Ground anchors diagnostic process based on elastic wave propagation method
PublikacjaThe paper is focused on analysis of elastic wave propagation in the context of diagnostics of ground anchors. Numerical simulations were performed to assess the possibility of evaluation of the anchorage quality. It was assumed that the quality and the load capacity of the anchor system directly depend on the length, on which mortar and steel cooperate.
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Manganese Phosphatizing Coatings: The Effects of Preparation Conditions on Surface Properties
PublikacjaManganese phosphate coating could be used to protect the surface of steel products. However, it is essential to determine the effects which process parameters, as well as the types of additives used, have on the efficiency of coating deposition. Thus, we present here a process of phosphatization of low-alloy steel (for 15 min at 95 ◦C) in manganese/nickel baths followed by a passivation process with the use of a silicon and zircon...
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Influence of the Widespread Use of Corten Plate on the Acoustics of the European Solidarity Centre Building in Gdansk
PublikacjaThis paper describes the relationship between a strong architectural vision that is difficult to balance, and user expectations in terms of acoustics. The focus is on the use of corten steel as the dominant finishing material on façades and interiors to achieve an expressive, symbolic message through program-based design. The architectural premises justifying the adopted solutions are presented, especially the universality and...
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Burnout Investigation of Small Diameter Tubes Immersed in Nanofluids
PublikacjaThis paper deals with research into pool boiling critical heat flux (CHF) of water–Al2O3, water–TiO2 and water–Cu nanofluids on horizontal stainless steel tubes. The experiments were conducted under atmospheric pressure. Nanoparticles were tested at concentrations of 0.001%, 0.01%, 0.1% and 1% by weight. Ultrasonic vibration was used in order to stabilize the dispersion of the nanoparticles. Although dispersants were not used to...
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Novel application of dynamic electrochemical impedance monitoring to a cataphoretic coating process
PublikacjaThe paper presents a novel method of on-line impedance monitoring of cataphoretic coating application process. Utilization of dynamic electrochemical impedance spectroscopy (DEIS) overcame the fundamental problem connected with non-stationarity of the aforementioned coating deposition process, which eliminates classical impedance spectroscopy technique from a real-time description of cataphoresis. The paper illustrates selected examples...
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Buckling Analysis of Cold Formed Silo Column
PublikacjaThe paper is devoted to stability analysis of different models of steel cold formed silo column. The steel cylindrical silos are often composed of corrugated walls and vertical open-sectional columns uniformly placed along the silo circumference. Both the whole 3D silo, a simplified model consisting of one column with a part of the silo walls, and a single column resting on elastic foundation provided by the silo walls were analyzed....
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The Influence of Selected Parameters of Numerical Modelling on Strains and Stresses at Weld Toe Notch
PublikacjaLatest development in the field of welding technology and prefabrication enabled massive production of thin-walled sandwich structures. Multi-layered sandwich structures are fabricated with the use of high-power CO2 lasers, friction welding, arc welding, hybrid welding, or other technique designed for the special purpose. Steel or aluminium alloy plates with thickness between 1 and 5 mm are connected by internal stiffeners. Strength...
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The Application of Cluster Analysis in the Assessment of the Weldability of Unalloyed Steels
PublikacjaNon-alloy steels constitute a large group of steels characterised by diversified chemical composition, structural morphology and a wide range of mechanical properties (determining weldability). The paper presents results of multidimensional analyses (based on cluster analysis) of 110 selected unalloyed steel grades. Properties adopted as diagnostic features included the chemical composition, mechanical properties (yield point)...
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Risks caused by microbiologically influenced corrosion in diesel fuel storage tanks
PublikacjaMicrobiologically influenced corrosion (MIC) poses serious problems for the petrochemical and refinery industries. Particularly favourable conditions for MIC arise in storage tanks and transmission pipelines for mixtures of diesel oil with the addition of a biocomponent (in Poland 7%). The best conditions for the development of MIC occur at the fuel-water interface, where microorganisms are provided with a source of food and water,...
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Ocena stanu technicznego rurociągu przesyłowego zawiesiny popiołów w Elektrowni Ostrołęka B
PublikacjaPrzedmiotem pracy był rurociąg przesyłowy zawiesiny popiołów przesyłanych z Elektrowni Ostrołęka B. Celem pracy było potwierdzenie przynależności próbek yvyciętych z rurociągu do określonego gatunku stali i ocena stanu materiału po eksploatacji. Dla zrealizowania tego celu wykonano: - analizę składu chemicznego materiału pobranego ze stalowych rur, - mikroanalizę warstw wierzchnich na powierzchni wewnętrznej i zewnętrznej, -...
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Investigating lubricants behaviour in microgravity for vibration damping purposes
PublikacjaVibration is one of the harshest environments an object is exposed to during and after launch into space on a launch vehicle. Such vibrations should be damped to avoid destruction of the spacecraft or its elements. Currently, active and material damping is used. A possibility of using lubrication as the damping factor is suggested by some research. MoS2 is a typical solid lubricant used in space applications. Its properties vary...
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Carbon dioxide sequestration by industrial wastes through mineral carbonation: Current status and perspectives
PublikacjaMineral carbonation using natural minerals or industrial wastes is a safe and promising strategy for CO2 sequestration. Application of industrial wastes for this purpose has significant ecological and environmental value, which is one of the key green technologies in the global carbon mitigation. This review summarizes the current research status of CO2 mineralization by industrial wastes. This work surveys the mechanisms and capacities...
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Badania nośności na zginanie innowacyjnego kształtownika giętego na zimno typu GEB
PublikacjaLekkie 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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Standard and modified falling mass impact tests on preplaced aggregatefibrous concrete and slurry infiltrated fibrous concrete
PublikacjaAlthough several studies have been conducted to evaluate the impact response of concrete using theAmerican Concrete Institute (ACI) 544-2R falling mass impact test, the variations in test results are themain drawback of this testing method. This study aims to reduce the variations in experimental impacttest results by introducing two simple test setup modifications; (1) using coarse or fine aggregate bed-ding as an alternative...
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The correlation of fractal dimension to fracture surface slope for fatigue crack initiation analysis under bending-torsion loading in high-strength steels
PublikacjaIn this study, the fractal dimension of fatigue fracture surfaces is investigated in order to find an alternative failure loading indicator. Some of many metrological factors are generalized by reducing the fracture surface structure to one factor and develop an entire fracture surface procedure by analyzing the impact of surface slope and calculation resolution. Three notched geometries are studied under cyclic bending-torsion:...
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Guided ultrasonic waves for detection of debonding in bars partially embedded in grout
PublikacjaThis paper deals with theoretical, numerical and experimental investigations of guided wave propagation in multilayered cylindrical bars with pre-existing debonding. The research focuses on a complex description of the nature of the wave phenomena occurring in a debonded specimen with a special emphasis on the influence of the location of damage on the wave conversion and diffraction. Experimental non-destructive and destructive...
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Debonding Detection in Reinforced Concrete Beams with the Use of Guided Wave Propagation
PublikacjaOne of the most frequent damage of the reinforced concrete structures is debonding between steel bar and concrete cover. In the case of debonding occurrence not only the strength of the structure decreases, but also it is more vulnerable to corrosion damages. For this reason fast and effective methods of debonding detection in an early stage of its development need a significant boost. The paper presents analytical and experimental...
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Jumping Wave Characteristic during Low Plasticity Burnishing Process
PublikacjaDuring the low plasticity burnishing process of soft materials such as carbon steel with a hardness of up to 40 HRC (Rockwell grade) a raised structure of the material known as the Jumping Wave forms in front of the tool roll. This phenomenon significantly disturbs the burnishing process, but is very poorly described in the literature. This article presents studies of this phenomenon on the example of burnished 1.0562 steel. The...
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The Influence of Modelling Material Zones on Strains and Stresses at Weld Toe Notch
PublikacjaThe latest development in the field of welding technology enabled prefabrication of thin-walled sandwich structures in an industrial scale. Sandwich structures fabricated of steel, or aluminium alloy plates and stiffeners are welded with the use of hi-power CO2 lasers. Strength analysis of such structures with the use of finite element method needs proper material modelling.In this paper the material model of steel sandwich panel...
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Evaluation of reformer tubes degradation after long term operation
PublikacjaPurpose of this paper is to show the effect of long-term service at elevated temperatures on microstructural changes of cast steel reformer tubes made of the alloy IN-519 (24%Cr, 24%Ni, Nb). The relationship between mechanical properties and microstructure degradation is discussed. Investigations were performed on five tubes taken from ammonia reformer furnace. Tubes worked at temperature of 880C and 3,2 MPa pressure. The operation...
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Influence of permanent magnetic field on wear performance of dry sliding contacts
PublikacjaResults of experimental studies concerning the influence of permanent magnetic field on wear of dry sliding contact are presented.It was found that magnetic field of horizontal orientation is causing temporary reduction of material's hardness. It also facilitates and accelerates removal process of wear particles from the contact zone.Formation of bulges, consisting of accumulated and compacted anti-ferromagnetic material produced...
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Carburization Behavior of High-Grade Pellets After Direct Reduction in Pure Hydrogen
PublikacjaCarburization is a critical aspect in the iron and steel industry as it significantly affects the mechanical and chemical properties of the final product. This study provides a comprehensive analysis of the carburization potential of high-grade quality iron ore pellets after direct reduction in pure hydrogen. The results show that the porosity of the pellets has a significant impact on the efficiency and success of the direct reduction...
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Single crystal growth and physical properties of MCo2Al9 (M= Sr, Ba)
PublikacjaSingle crystals of SrCo2Al and BaCo2Al9 were grown using a self-flux method. A LeBail analysis of the powder X-ray diffraction patterns show that both compounds crystallize in a hexagonal (P6/mmm) crystal structure with lattice parameters: a = 7.8995(1) Å, c = 3.9159(1) Å for SrCo2Al9, and a = 7.9162(2) Å, c = 3.9702(1) Å for BaCo2Al9 aluminide. The low temperature analysis of the heat capacity measurements give a Sommerfeld...
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The LaPdIn 4 indide and elementary properties of the LaTIn 4 ( T = Ni, Pd, Pt) materials family
PublikacjaThe indium-rich intermetallic compound LaPdIn4 is reported, prepared by arc-melting and annealing at 600 C. Single crystal X-ray diffraction found the material to be orthorhombic, space group Cmcm (No. 63), with lattice parameters a ¼ 4.5462(3) Å, b ¼ 16.9208(10) Å, and c ¼ 7.3100(5) Å. This previously unreported indide is isostructural with LaNiIn4 and LaPtIn4. It is demonstrated that all three compounds in the LaTIn4 (T ¼ Ni,...
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Superconductivity in the intermetallic compound Zr5Al4
PublikacjaPolycrystalline Zr5Al4 was synthesized using the arc-melting method. Powder X-ray diffraction confirms the previously reported crystal structure of the Ti5Ga4-type P63/mcm with lattice parameters: a = 8.4312(6) A , and c = 5.7752(8) A . Electrical resistivity and low-temperature magnetic susceptibility measurements indicate that Zr5Al4 exhibits superconducting behavior below 2 K. The normalized heat capacity jump at Tc= 1.82 K...
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(CsX)Cu5O2(PO4)2 (X = Cl, Br, I): A Family of Cu2+ S = 1/2 Compounds with Capped-Kagomé Networks Composed of OCu4 Units
PublikacjaThree new salt inclusion compounds (CsX)Cu5O2(PO4)2 (X = Cl, Br, I), phosphate analogues of the kagomé mineral averievite, are reported. Their crystal structures are composed of trigonal networks of corner-sharing OCu4 anion-centered tetrahedra, forming capped-kagomé planes, which can also be regarded as two-dimensional slices along the [111] direction of a pyrochlore lattice. Magnetization and heat capacity measurements reveal...
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Local material symmetry group for first- and second-order strain gradient fluids
PublikacjaUsing an unified approach based on the local material symmetry group introduced for general first- and second-order strain gradient elastic media, we analyze the constitutive equations of strain gradient fluids. For the strain gradient medium there exists a strain energy density dependent on first- and higher-order gradients of placement vector, whereas for fluids a strain energy depends on a current mass density and its gradients....