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The author has recently introduced the class of CNED sets in Euclidean space, generalizing the classical notion of NED sets, and shown that they are quasiconformally removable. A set E is CNED if the conformal modulus of a curve family is not affected when one restricts to the subfamily intersecting E at countably many points. We prove that several classes of sets that were known to be removable are also CNED , including sets of σ -finite Hausdorff (n - 1) -measure and boundaries of domains with n-integrable quasihyperbolic distance. Thus, this work puts in common framework many known results on the problem of quasiconformal removability and suggests that the CNED condition should also be necessary for removability. We give a new necessary and sufficient criterion for closed sets to be (C)NED. Applying this criterion, we show that countable unions of closed (C)NED sets are (C)NED. Therefore we enlarge significantly the known classes of quasiconformally removable sets. [ABSTRACT FROM AUTHOR]

Ferroelectric polymer-based separators, known for their flexibility, ease of synthesis, and modifiability through dopants, are currently under extensive study due its potential applications in electronic devices. PVDF nanocomposites, which combine the strengths of their constituents, currently lead in emerging technologies. This research employs Zinc oxide nanoparticles (ZnO NPs) as fillers in the PVDF matrix and investigates their structural, optical, thermal and electrical properties. ZnO NPs synthesized via the combustion method, are being incorporated with varying concentrations (2, 4, 6, 8, and 10 wt%), into PVDF nanocomposite (PNC) thin films through a solution casting process. The PNC thin films are characterized using XRD, FTIR, UV–Vis spectroscopy and thermogravimetric analysis (TGA). Dielectric properties are being explored across a frequency range from 20 to 2 MHz at room temperature, revealing enhanced dielectric constants at lower frequencies, decreasing with frequency due to Maxwell–Wagner interfacial polarization. With increasing frequency, AC conductivity and electric modulus exhibit enhancement. Complex impedance analysis via the Cole–Cole plot indicates a non-Debye type of dielectric relaxation with heightened conductivity. TGA demonstrates improved thermal stability in PNC thin films. These findings suggest the potential application of the prepared PNC thin films as separators in energy storage devices. [ABSTRACT FROM AUTHOR]

This work investigates the AC conductivity, impedance spectroscopy, and modulus formulation of varied compositions of glass samples within the modified borovanadate glassy system, synthesized using the melt-quenching technique. Up to 10 mol% of BaO, the AC conductivity shows a rising trend as BaO content rises; however, for x = 15&20 mol%, there is a drop. The Almond West model fits the experimental data of ac conductivity and parameters such as crossover frequency, frequency exponent (s), and direct current conductivity are retrieved. All samples feature a CBH conduction mechanism at varying frequencies, except for VBa1, which has a small polaron quantum mechanical mechanism. There is good agreement in the activation energy derived from conductivity (0.565–0.742 eV), electric modulus (0.526–0.616 eV), and impedance research (0.530–0.743 eV). Dielectric studies reveal non-Debye-type behavior. According to impedance formalism, electric conduction occurs through Ba2+ ions and electron/polarons. This characteristic renders the glasses well-suited for energy storage devices. [ABSTRACT FROM AUTHOR]

Silicophosphate, prepared from Tunisian siliceous sand, has been investigated as a potential oxide ion conductor. XRD and Rietveld refinement analyses confirm the formation of pure single-phase Si5P6O25 that crystallizes in the trigonal system with R-3 space group. The electrical conductivities and dielectric properties of this material have been studied using complex impedance spectroscopy from 10 to 106 Hz at a temperature range from 600 to 680 °C. The results show that the ionic conductivity σdc increases from 5.43 × 10− 5 S.cm− 1 at 600 °C to 0.23 × 10− 3 S.cm− 1 at 680 °C with an activation energy of 1.33 eV. The frequency dependence of AC conductivity could be explained by Jonscher's power law. The dielectric constant's decrease with frequency indicates a region of dispersion resulting from a polarization process' relaxation. The simulation of the oxygen conduction using the Bond Valence Site Energy (BVSE) model shows the presence of four interstitial sites used with equilibrium sites to form a zigzag isosurface of oxygen migration. The calculated activation energy is about 1.43 eV. [ABSTRACT FROM AUTHOR]

The complex lead-free perovskite ceramics, (1-x) BiFeO3-X(B/K) Ti/MnO3, where X = 0.05, 0.10 were fabricated by using a solid-state chemical reactions technology. The X-ray diffraction analysis exhibits the formation of the sample in rhombohedral crystal symmetry (#R3c). The average crystallite size for BKTM with 5% content and BKTM with 10% content was determined utilizing the Scherrer formula, resulting in sizes of 21.83 nm and 27.81 nm, respectively. Fourier-transformed infrared spectroscopy spectrum analysis also supports the formation of compounds based on the characteristics peak corresponding to Bi-O and Ti-O bonds. Scanning electron microscope (SEM) shows the distribution of grain and surface morphology. The surface morphology indicates dense grain development with no fractures. The mean grain size for BKTM with 5% content is approximately 2.73 μm, whereas for BKTM with 10% content, it is about 0.49 μm. This discovery could help with grain and grain border resistive and capacitive properties. The impedance study reveals the electrical behavior of the sample. The semicircular arc of the complex impedance and electrical modulus spectrum plots reveal the substance’s semiconducting properties. [ABSTRACT FROM AUTHOR]

BaBiLaNbVO9 is a lead-free compound and has been synthesized by solid-state technique. The formation of the compound was confirmed by X-ray diffraction and is found to be crystallized in the monoclinic (space group P 21) crystal system (a = 13.7464± 0.0015 Å, b = 4.0156± 0.0012 Å, c = 12.4946 ± 0.0018 Å, β = 93.48 ± 0.01o). The crystallite size was found to be 52.91 nm. SEM and EDX studies analyzed the morphology, composition, and elemental distribution in the specimen. The average grain size is about 1.0651 μm. Several properties, such as frequency and temperature response resistivity, conductivity, and dielectric behaviours of the compound, have been analyzed. The overlapping large polaron tunnelling (OLPT) and correlated barrier hopping (CBH) models are appropriate for electrical conduction in the compound. The energy band gap (Eg) of the material was 2.40 eV, suitable for optoelectronic devices. Ferroelectric behaviour may be deduced from symmetric and well-shaped P-E hysteresis loops. The impedance study satisfies the negative temperature coefficient of resistance (NTCR) behaviour, which is suitable for thermistor devices and its correlated application. [ABSTRACT FROM AUTHOR]

This paper discusses the structural, microstructure and electrical properties of perovskite oxide lanthanum nickel LaNiO3, synthesized by the sol–gel reaction technique that was investigated. The prepared material was doped with bismuth and niobium and studied their properties. The Rietveld refinement of the X-ray diffraction pattern suggests that the compound has a monoclinic phase at room temperature with a P21/n space group. Scanning electron microscopy surface morphology analysis of the sample showed closed packing of grains with good density and very little porosity. The frequency-dependent modulus of the material is investigated in the temperature range from 200 K to 360 K and in range frequency between 1 kHz and 1 MHz. The Cole–Cole model is used to analyze the dielectric relaxation phenomenon. The complex impedance data are analyzed by an electrical equivalent circuit consisting of a resistance and a constant phase element, where the ideal capacitance part is replaced by a constant phase element. The frequency-dependent conductivity spectra follow the Jonscher power law. Nevertheless, the Arrhenius-type conduction mechanism was found to be active in the sample with activation energy of 0.168 eV. The electrical property of the sample was found to be independent of temperatures, making it a potential candidate for thermally stable capacitor application. [ABSTRACT FROM AUTHOR]

In this paper, we study the existence of limits at infinity along almost every infinite curve for the upper and lower approximate limits of bounded variation functions on complete unbounded metric measure spaces. We prove that if the measure is doubling and supports a 1-Poincaré inequality, then for every bounded variation function f and for 1-a.e. infinite curve γ , for both the upper approximate limit f ∨ and the lower approximate limit f ∧ we have that lim t → + ∞ f ∨ (γ (t)) and lim t → + ∞ f ∧ (γ (t)) exist and are equal to the same finite value. We give examples showing that the conditions of the doubling property of the measure and a 1-Poincaré inequality are needed for the existence of limits. Furthermore, we establish a characterization for strictly positive 1-modulus of the family of all infinite curves in terms of bounded variation functions. These generalize results for Sobolev functions given in Koskela and Nguyen (J Funct Anal 285(11):110154, 2023). [ABSTRACT FROM AUTHOR]

The incorporation of sugar palm fiber (SPF) into polymer composites presents an environmentally conscious and promising alternative to synthetic reinforcement materials. These composites exhibit impressive mechanical stiffness, strength, elongation, and thermal stability. Extensive research has centered on characterizing the thermal, mechanical, and physical behaviors of SPF-reinforced polymer composites under varying conditions. Despite their exceptional qualities, these composites have mainly been utilized in traditional applications such as brooms, brushes, and ropes. This study conducts a comprehensive exploration of their properties, employing dynamic mechanical analysis (DMA) to assess the thermal stability of SPF-reinforced polymer composites in both thermoplastic and thermoset matrices. The investigation focuses on critical parameters including storage modulus (E′), loss modulus (E′′), complex modulus (E), and damping factor (tan δ), with particular attention to temperature-sensitive interfacial bonds between fibers and diverse polymer matrices. Factors such as matrix type, filler type, processing and post-processing conditions, frequency, temperature, fiber length, loading, volume fraction, orientation, and treatment significantly influence the DMA properties of natural fibers. This review synthesizes the latest literature of the past decade, offering an in-depth overview of SPF polymer composites, including hybrid composites, and exploring their diverse applications. Furthermore, the study evaluates the effects of integrating synthetic fibers and employing chemical treatments on the DMA properties, impact resistance, and post-impact performance of SPF-reinforced polymer composites. By advancing knowledge in this domain, this comprehensive review provides valuable insights into designing and optimizing these composites for a wide range of engineering applications. [ABSTRACT FROM AUTHOR]

In this paper, we establish six necessary and sufficient conditions for a homeomorphism of R n onto itself to be strongly quasisymmetric. These conditions are quantitative in terms of conformal moduli of disjoint continua as well as the geometric modulus, which was recently introduced by Tukia and Väisälä. Note that all of them are equivalent to bilipschitz continuity with parameters depending also on two fixed points. As an application, we obtain several quantitative characterizations for a homeomorphism of the Riemann sphere R ¯ n onto itself to be strongly quasimöbius. [ABSTRACT FROM AUTHOR]

This study focuses on the preparation of lithium diphosphate compound LiCeP2O7 via conventional solid-state reaction. Analysis using the Rietveld refinement of the X-ray diffraction pattern reveals that the sample adopts a monoclinic structure at room temperature. Surface morphology is further examined through SEM. Additionally, complex impedance and electrical modulus spectroscopy analyses indicate the presence of non-Debye-type relaxation behavior. The direct current (dc) conductivity exhibits Arrhenius behavior, with activation energies of 0.94 eV in region I and 1.21 eV in region II, indicating thermally activated lithium-ion conduction. The thermal behavior of the exponent parameter "s" suggests a transition in the conduction mechanism from large polaron tunneling to small polaron tunneling that occurs at 533 K. Electric modulus studies confirm that the ionic conduction relaxation process is thermally activated and exhibits a spread of relaxation time. Understanding the ionic conduction mechanism will facilitate the design of efficient ionic conductors for battery applications. [ABSTRACT FROM AUTHOR]

The polymer with nanoparticles tethered at each end is a unique model for unraveling the effect of chain ends on the polymer dynamics. We investigated the rheological behavior of this kind of polymer by using nonequilibrium molecular dynamics simulation. The effect of polymer lengths and nanoparticle radii on the complex moduli and viscosity was examined. The dependence of complex moduli on the frequency becomes less pronounced as the polymer is short or the nanoparticle is large. The shear thinning behavior was revealed for these systems, and the scaling exponent of complex viscosity with respect to the frequency was found to change from −1/2 to −3/4 as the polymer shortens or the nanoparticle enlarges. The rheological behavior was further explained by analyzing the mean square distance of nanoparticles. The simulation results were compared with the existing experimental finding, showing an agreement. The work provides information for understanding the chain end effect on polymer rheology. [ABSTRACT FROM AUTHOR]

The solid-state reaction route created the lead-free dielectric material CaBiLaNbVO9 at a high temperature. The polycrystalline compound belongs to a monoclinic crystal structure having dimensions a = 10.6738 Å, b = 10.4488 Å, c = 7.1793 Å, and V = 798.04 Å3. The grain size is calculated to be 1.1029 µm. The doping of La3+ at the Bi-site and divalent cation Ca2+ substituted at site-A and Nb5+, V5+ in the site-B of ABO3 has considerably modified the structural, dielectric, and electrical conduction mechanism. The study of ac conductivity (frequency-temperature characteristics) shows CBH (correlated barrier hopping) and NSPT (non-overlapping small polaron tunneling) conduction mechanisms. Non-Debye type relaxation has been observed using impedance analysis. The modulus and impedance study have been used to confirm the short-range order of charge carriers. The average transmittance of the compound is about 82–84%, and absorption is in the range of 0.1–1.0% in the visible area applicable for transparent conductive oxide. The energy band gap is 2.73 eV. The analysis of the resistive and capacitive properties indicates the material is an electronic component for the creation of devices. [ABSTRACT FROM AUTHOR]

The common practice of freezing meniscal allograft tissue is limited due to the formation of damaging ice crystals. Vitrification, which eliminates the formation of damaging ice crystals, may allow the mechanical properties of meniscal allograft tissue to be maintained during storage and long-term preservation. The primary objective of this study was to investigate the differences between fresh, frozen, and vitrified porcine lateral menisci examining compressive mechanical properties in the axial direction. Unconfined compressive stress-relaxation testing was conducted to quantify the mechanical properties of fresh, frozen and vitrified porcine lateral menisci. The compressive mechanical properties investigated were peak and equilibrium stress, secant, instantaneous and equilibrium modulus, percent stress-relaxation, and relaxation time constants from three-term Prony series. Frozen menisci exhibited inferior compressive mechanical properties in comparison with fresh menisci (significant differences in peak and equilibrium stress, and secant, instantaneous and equilibrium modulus) and vitrified menisci (significant differences in peak stress, and secant and instantaneous modulus). Interestingly, fresh and vitrified menisci exhibited comparable compressive mechanical properties (stress, modulus and relaxation parameters). These findings are significant because (1) vitrification was successful in maintaining mechanical properties at values similar to fresh menisci, (2) compressive mechanical properties of fresh menisci were characterized providing a baseline for future research, and (3) freezing affected mechanical properties confirming that freezing should be used with caution in future investigations of meniscal mechanical properties. Vitrification was superior to freezing for preserving compressive mechanical properties of menisci which is an important advance for vitrification as a preservation option for meniscal allograft transplantation. [ABSTRACT FROM AUTHOR]

As purchased, PVDF and MWCNT were used to synthesise PD by varying the volume fractions of MWCNT (fMWCNT) into the polymer matrix through the novel cold-pressing method. The structure, microstructure and the electrical properties of the samples were obtained through XRD, FESEM, and Impedance analyzer. The microstructures of the PD show the presence of two components, such as the spherulites of PVDF (retained due to the novel cold-pressing) and the distribution of MWCNT into the PVDF matrix. The extent of distribution of MWCNT in the PD increases and the clustering of MWCNT also increases with increase of fMWCNT. The PD undergo an insulator to metal transition (IMT), with a non-universal low percolation threshold (fc) value of fMWCNT = 0.006, attributed to the high aspect ratio of MWCNT and the adhesiveness/method of preparation of the PD. The scaling equations hold good in the critical region around IMT, and the non-universal critical exponents [s = 0.36 ± 0.03, s' = 1.26 ± 0.1] were obtained. Impedance, Nyquist and Modulus spectra for the PD have been implemented to understand the relaxation behaviour/microstructure of the samples. For fc, a broad relaxation, understood by a modified Kohlrausch, Williams and Watts (KWW) function, showing a non-Debye type relaxation associated with the universal stretched coefficient of β = 0.54 is obtained. The σeff with frequency obeys universal Jonscher's power law with exponent, k = 0.91 ± 0.01. [ABSTRACT FROM AUTHOR]

This study investigated the capillary rise potential and dynamic behavior of rubber particles-silty sand mixtures. A series of capillary rise tests and undrained cyclic triaxial tests were designed and performed on pure silty sand and rubber soil mixtures. The impact of rubber particles content (RC) and mean grain size ratio ( D 50 , r / D 50 , s ) of the mixtures was investigated. The results showed that the increase of RC and D 50 , r / D 50 , s decreased the capillary rise behavior. Compared with pure silty sand, the total capillary water mass increment of mixtures with 30% rubber particles with 41.3 and 7.9 D 50 , r / D 50 , s decreased by 52.7% and 35.1%, respectively. An increase in D 50 , r / D 50 , s resulted in a harder performance for the mixtures, whereas an increase in RC resulted in softer performance for the mixtures. Compared with pure silty sand, the maximum Young's modulus of mixtures with 30% rubber particles (at 200 kPa confining pressure) for 41.3 and 7.9 D 50 , r / D 50 , s decreased by 52.7% and 35.1%, respectively. An increase in the normalized Young's modulus was associated with a decrease in RC and increase in D 50 , r / D 50 , s . An increase in RC and decrease in D 50 , r / D 50 , s resulted in an increase in damping ratio. A set of empirical equations was proposed to describe the normalized Young's modulus and damping ratio. The results presented here provide new ideas for the use of rubber soil mixtures in geotechnical engineering. [ABSTRACT FROM AUTHOR]

The extraordinary physical characteristics and enormous potential for technological applications of multiferroic materials have sparked recent interest in these materials. In this work, the composition of aliovalent ions Ba2+/Ti4+ doped YMnO3 i.e., Y0.95Ba0.05Mn0.95Ti0.05O3 ceramic sample was prepared through the solid-state method. The structural, dielectric, and ferroelectric properties of the prepared sample were studied in detail. X-ray diffraction patterns unveil the hexagonal crystal structure of the ceramic owning P63cm space group symmetry, which is also authenticated by accomplishing Rietveld's refinement of the sample. Nevertheless, the ceramic demonstrated the emergence of the orthorhombic peak. The formation of phase composition of the prepared sample was proved through FT-IR spectroscopic measurement. The Raman spectroscopy analysis of the sample reveals the presence of subtle vibrational modes. The investigation of the dielectric and electrical properties of the prepared sample at frequencies between 1 kHz and 1 MHz and temperatures spanning from 303 to 623 K has yielded significant outcomes. These outcomes include dielectric dispersion, conduction mechanism, and relaxation process of the samples, which are highlighted in this study. The ferroelectric behaviour of the prepared sample has been studied using PE hysteresis loop measurement. [ABSTRACT FROM AUTHOR]

The effect of frequency and temperature on the permittivity and transport properties of calcium manganese was investigated. The sample was synthesized using a simple, an economic and a reproducible complex polymerizable route. Thereafter, it was characterized by the X-ray diffraction and complex impedance spectroscopy techniques. The obtained results showed that CaMnO3–δ exhibits a semiconducting behaviour between room temperature and 400°C. Beyond that temperature, the perovskite behaves as a metal. As for the activation energy, it showed a change around 400°C, which is attributed to the first-order transition from semiconducting to the metallic behaviour. Moreover, the dielectric constant and the loss exhibited a decreasing trend with increasing frequency, which is a characteristic of polar dielectrics. Between 25 and 400°C, the maximum barrier height increased from 0.1 to 0.32 eV. The low dissipation factor at high frequencies seems to be an interesting feature highlighting the promising use of CaMnO3–δ in high-frequency microwave device applications. [ABSTRACT FROM AUTHOR]

Strength and deformation characteristics of jointed rocks are important parameters for the design of many civil and mining engineering structures. These parameters are difficult to obtain from direct testing of jointed rocks; hence it is usual practice to derive them through indirect approaches. In the present study, an attempt is made to obtain rough estimates of strength and modulus of jointed rocks through P wave velocity. Jointed specimens of a model rock were prepared for laboratory testing. Joints at different orientations and comprising of different joint roughness coefficients were used (JRC = 2–4, 12–14 and 14–16). Ultrasonic P-wave velocity and UCS tests were conducted on the specimens. The effect of joint orientation and joint wall roughness on P-wave velocity was studied. An index, Joint Factor was used to quantify the effect of joint attributes on strength and modulus of jointed rock. It was observed that P-wave velocity is closely linked with Joint Factor. This study suggests a correlation to obtain Joint Factor Jf from P-wave velocity. P-wave velocity may be measured in the field and Jf may be computed through the suggested correlation. The computed Jf may then be used to get the strength and modulus values of jointed rocks. Charts are also suggested to roughly assess the shear strength parameters, cmass and ϕmass of the jointed rock. [ABSTRACT FROM AUTHOR]

A359 aluminum alloy composite containing 20 vol. % silicon carbide particles was remelted, and 100-mm diameter foam ingots were prepared using 0.75 wt. % of titanium hydride (TiH2). Three identical experiments each were carried out at two foaming temperatures (640 and 660 °C) to check the reproducibility of the cell structure and foam properties. Foams made at 640 °C were reproducible in terms of foam expansion, cell size and cell size variation along the ingot height. The property scatter, evaluated in terms of relative standard deviation, is similar for density and modulus of the foam. For compressive plastic strength, the scatter is double than for density. The density and mechanical properties are reproducible within these scatters. Foams prepared at 660 °C, on the other hand, suffered from liquid foam collapse during solidification and hence couldn't be qualified for detailed study of reproducibility. The collapse resulted in distortion of the foam ingot and elongated cell structures in other parts. However, the cell size and mechanical properties in the un-distorted region are comparable with those foamed at 640 °C. Overall, good quality cell structure and consistent mechanical properties could be obtained in foams processed at 640 °C. [ABSTRACT FROM AUTHOR]

This study investigated the mechanical and tribological properties of branched polyethyleneimine/polyacrylic acid (bPEI/PAA) coatings. (bPEI/PAA) coatings were prepared on Ti6Al4V substrate using layer-by-layer assembly technique. The coatings have good tribological behaviors with the rotating mode under the deionized water. In particular, (bPEI/PAA)40 has the lowest friction coefficient with the reciprocating mode, about 0.14. The cross-linked network structures were formed with the electrostatic attraction. The amorphous phase of coatings provides a crucial buffer during the loads applying on the surface. The (bPEI/PAA)n coatings have the swelling ability, and there are large decreases of storage modulus and loss modulus in deionized water compared with removing from the deionized water. The excellent tribological properties are ascribed to the cross-linked network structure, amorphous phase, and swelling ability. [ABSTRACT FROM AUTHOR]

It is extremely important to investigate the mechanical properties and failure characteristics of granite at the mesoscale to understand the mesoscopic evolution mechanism of the time-dependent fracture of deep-buried hard rocks. This study explores the mesoscopic mechanical properties (i.e., hardness, Young's modulus, and fracture toughness) of the primary granite minerals and their interfaces using nanoindentation. Micro X-ray computed tomography was used to analyze the fracture characteristics of the failed Brazilian disc of granite. Moreover, two homogenization upscaling methods were used to calculate granite's Young's modulus and compared with that from uniaxial compression test results. The results demonstrate the following: (1) The mechanical properties of granite minerals are related to the peak load of nanoindentation. Young's modulus and hardness of quartz, K-feldspar, and plagioclase decrease with an increase in the peak load and tend to be stable when the peak load reaches 5000 μN, whereas Young's modulus and hardness of biotite at multiple peak loads are in variability and irregularity. (2) Young's modulus and hardness of quartz–plagioclase and quartz–biotite interfaces are between quartz and plagioclase and quartz and biotite, respectively. Furthermore, a linear formula is proposed to estimate fracture toughness based on Young's modulus of granite minerals. (3) The generalized means method that predicts granite's Young's modulus is more accurate compared to the Mori–Tanaka method. (4) Under Brazilian splitting conditions, ~ 84% of tensile cracks along intragranular cracks primarily occur in feldspar minerals, while ~ 16% along grain boundaries occur at feldspar–biotite interfaces. Highlights: Mesomechanical properties of granite minerals and mineral interfaces. A linear relationship between the fracture toughness and Young's modulus. Homogenization methods used for upscaling the mesoscopic Young's modulus of granite. [ABSTRACT FROM AUTHOR]

In this study, the impact of Nd doping on the structural, microstructural, dielectric, ferroelectric, and transport properties of Pb (1 - x) Nd x (Fe 0.5 Nb 0.5) 1 - x / 4 O 3 (PNFN) solid solutions ( x = 0 , 0.02 , 0.04 , 0.08 , and 0.1 ) is reported. For all the solid solutions, room temperature Rietveld refined X-ray diffraction (XRD) analysis reveals the monoclinic crystal structure with Cm space group. From Field emission scanning electron microscope (FESEM) studies, the polyhedral-shaped grains are found to be homogeneously distributed. Variation of dielectric properties with temperature displays the decrease of phase transition temperature (TC) with increasing Nd content. The temperature-dependent AC conductivity follows the Arrhenius behavior and the activation energies are calculated for high temperature regions. The frequency dependent AC conductivity behavior obeys the Johnscher's power law. Impedance spectroscopy results show the impact of conductivity from the bulk (grain) and displays non-Debye type of behaviour. Electric modulus demonstrates thermally activated relaxation phenomenon in the materials. Polarization vs. electric field (P-E) loops analysis confirms the ferroelectric nature of the materials. With increase in Nd concentrations, the value of remanent polarization (2Pr) increases, on the other hand, the coercive field (2Ec) value decreases. Both of these properties are suitable for enhancement of the physical properties of the multiferroic materials. [ABSTRACT FROM AUTHOR]

In this paper, we show that Orlicz–Sobolev spaces W 1 , φ (Ω) can be characterized with the ACL- and ACC-characterizations. ACL stands for absolutely continuous on lines and ACC for absolutely continuous on curves. Our results hold under the assumptions that C 1 (Ω) functions are dense in W 1 , φ (Ω) , and φ (x , β) ≥ 1 for some β > 0 and almost every x ∈ Ω . The results are new even in the special cases of Orlicz and double phase growth. [ABSTRACT FROM AUTHOR]

Eugenol is widely used as bio-based raw materials, based on functional groups such as hydroxyl, methoxy, and allyl contained in the molecule that has van der Waals forces or chemical reactivity. In this paper, eugenol and 1,3,5,7-tetramethyl cyclo tetrasiloxane (D4H) were used as raw materials to synthesize a phenolic siloxane crosslinking agent (PSCA) by heterogeneous catalytic hydrosilylation method(ology). Low-modulus gels (LMG) were prepared by the volcanization of PSCA and vinyl terminated silicone oil (DVi-Si). A dual crosslinking network is fabricated through chemical bonding and physical interaction present in the LMG. The results show that the PSCA crosslinked LMG holds a low elastic modulus of 6.04 kPa and suitable elastic recovery property. It's attractive to use LMG as a thermal conductive gel matrix for its superior flexibility, enhancing conformality and decreasing thermal contact resistance for future thermal management materials (e.g thermal conductive gel). [ABSTRACT FROM AUTHOR]

In this research, it was explored how the strength of sand core would be affected by the silicate binder with varying modulus and different cation types (Na and K) and micro-silica powder. To be specific, the microscopic morphology of the bonding bridge was examined by scanning electron microscope (SEM), while the changes in internal structure were revealed through Fourier transform infrared spectrum (FT-IR) analysis. It was discovered that with the modulus reduced from 2.3 to 1.3, there was a progressive increase from 20% to 50% in the amount of micro-silica powder as required for the sand cores to reach the maximum bonded strengths. Under the same conditions, the strength of sand cores bonded by potassium silicate was improved compared to sodium silicate. According to FT-IR analysis, the decline in modulus improved not only the concentration of OH– but also the density of active groups inside silicate solution, which is conducive to the formation of Si–O–Si bonds through reaction with micro-silica powder. Meanwhile, the results of the EDS and FT-IR analysis suggest a higher concentration of Si–O–Si bonds in the mixture of potassium silicate and micro-silica powder. Consequently, the sand core bonded by potassium silicate outperformed that with sodium silicate in both tensile strength and storage performance. [ABSTRACT FROM AUTHOR]

K2CuP2O7 potassium diphosphate has been obtained by the traditional solid-state reaction method and characterized by different techniques. Rietveld's refinement of XRD data confirmed orthorhombic symmetry, belonging to the Pbnm space group. SEM mapping and energy dispersive spectroscopy (EDS) indicated the same morphology and different particle sizes. The electrical and dielectric properties of this material were investigated using impedance spectroscopy in the frequency range 100 Hz–1 MHz and temperature range 603–673 K. The temperature dependence of the dc conductivity obeys Arrhenius' law. The frequency-dependent AC conductivity was found to obey Jonscher's power low. The values ​​of the frequency exponents increase with increasing temperature. The conduction mechanism was therefore attributed to the small non-overlapping polaron tunnel effect (NSPT). [ABSTRACT FROM AUTHOR]

A variety of rechargeable Na batteries are under development for use in energy storage systems. For these batteries, a Na-ion conducting solid electrolyte is desired. One such electrolyte under consideration is NaSICON (Na Super Ionic Conductor). One important aspect of the NaSICON electrolytes that has been overlooked is their mechanical properties. Such information is required if NaSICON has to be used as a solid electrolyte in rechargeable Na batteries that exhibit long life cycle and high power. This paper reviews the elastic, plastic, and fracture properties of NaSICON electrolytes. Young's modulus values for NaSICON range from ~ 56 to 97 GPa with Poisson's ratio ~ 0.26. Hardness values determined by micro-indentation for NaSiCON are 4.4–4.9 GPa. The value of the Gilman-Chin parameter suggests the bonding in NaSICON is covalent. As a result of its covalent bonding, NaSICON exhibits a high Peierls which leads to low fracture toughness, with KIC values ~ 1–1.5 MPa m0.5. The fracture strength of NaSICON is between 50 and 110 MPa and is controlled by the amount and size of the second-phase ZrO2 particles. [ABSTRACT FROM AUTHOR]

Cobalt sulphides, including CoS, CoS2, Co3S4 and Co9S8, have been studied as potential anode materials for Li- and Na-ion batteries. However, the mechanical properties of the cobalt sulphides have not been intensively investigated. In this work, density functional theory (DFT) calculation was employed to study the mechanical properties of the cobalt sulphides mentioned above. Besides, the mechanical properties of final products of lithiation/sodiation of Co9S8 have been calculated, including the bulk modulus, shear modulus, Young’s modulus and Poisson’s ratio. This work provides an insight into understanding the electrochemical performance of Co9S8 material as anode material for Li- and Na-storage during the cycling process. [ABSTRACT FROM AUTHOR]

Most commercially-available mechanical testing devices are bulky, expensive, and unable to evaluate changes in sample microstructure under load. This leaves a crucial gap in understanding between material structure and bulk mechanical properties. Our objective was to fabricate a mechanical testing device small enough to fit in most upright or inverted microscopy stages and able to position samples to allow for simultaneous mechanical and microstructural characterization. Parts were 3D printed using the hobbyist-friendly Fused Filament Fabrication technique, then assembled with commercial fasteners and translation components to create a mechanical testing device that utilized the deflection of plastic posts to determine sample reaction forces under applied strain. Video of sample deformation was analyzed using a custom processing script to calculate stress and strain behavior in an automated and high-throughput manner. This device was able to perform mechanical characterization with an accuracy comparable to commercial mechanical testing devices for a wide range of nonlinear and viscoelastic samples under dry and hydrated conditions. Additionally, the device showed compatibility with different upright and inverted microscopes and was able to demonstrate accurate mechanical testing results when used with these instruments. We successfully developed a device capable of accurately testing a majority of soft materials in the field of Biomedical Engineering with the ability to perform additional microstructural characterization using microscopy at a price point of $600. [ABSTRACT FROM AUTHOR]

With the increase in the use of high-density polyethylene (HDPE) products and the serious long-term hazard they pose to the environment, there has been an increasing need to decrease the release of these materials to the environment as waste. This study sets out to develop and optimize the mechanical properties of the GLP-HDPE composite, a sustainable material made from agro residues (ginger leaf particles (GLP)) and high-density polyethylene waste materials. The Taguchi robust technique, analysis of variance, and regression analysis were employed to optimize, analyze, and model the behavior of the composite materials with respect to the developmental factors of particle size and particle content. The optimum bending modulus of elasticity (MOE), modulus of rupture (MOR), and impact energy (IE) of the developed composites was 2490 MPa, 11.90 MPa, and 4.1 J at a particle size/particle content combination of 710 µm/35%, 520 µm/35%, and 710 µm/45%, respectively. Analysis of variance at 95% confidence level showed that the particle content had a significant effect on the MOE, MOR, and IE of the GLP-HDPE composite with a minimum percentage contribution of 71.61%. Equations for predicting the MOE, MOR, and IE of the composites were developed with good prediction accuracy. [ABSTRACT FROM AUTHOR]

The major problems disturbing the rheology of magnetic fluid are deformation of magnetic aggregate and destruction of field-induced structure, and this has caused major drawbacks to the rheological systems. The magnitude of the deformation is dependent on the percentage of the strain rate. To curtail the drawback and improve the rheology of the magnetic nanofluid, low strain rate application is required for fluid material testing. Henceforth, we examine the effect of strain rate and magnetic field on the rheological properties of zinc ferrite ferrofluid (FF) using oscillatory sweep test. The rheology of the fluid is examined in the absence and presence of magnetic field at strain amplitude 1%, 10%, 33%, and 100%. The magnitude of the deformation varied as the strain percentage is altered. Low deformation is formed at strain 1% and 10%, this results to the formation of improved and better rheological systemic function, and the rheological function is partially weakened at strain 33%, whereas structural deformation is higher at strain 100%. At strain 100%, the rheological system is largely weakened, but at strain 1%, the rheological system is enhanced. At low strain, high complex magnetoviscosity, low shear stress, low rotating magnetic field, and improved viscoelastic system are formed, but, at high strain application, low complex magnetoviscosity, high shear stress, speedy rotating magnetic field and poor viscoelastic system are formed. A steady-state flow is formed when low relaxation modulus is applied. At high strain, high rotation is formed, and this breaks the rotating magnetic field and destroys the magnetic structure, but at low strain, the rotation of the rotating magnetic field is low, and this protects the aggregates from destruction. The synthesized particles were ultra-sonicated and coated with oleic acid to curtail agglomeration of the particle. The storage modulus (G′) is largely greater than loss modulus, and this established the formation of dominant elastic structure. From TEM analysis, a spherically shaped nanoparticle is formed. The XRD analysis indicates the formation of cubic structure and Fe-phase in trivalent state. The hopping lengths in the tetrahedral site A and octahedral site B are 3.61 nm and 2.94 nm, while the lattice parameters a and c are 8.3298 Å and 13.7501 Å. [ABSTRACT FROM AUTHOR]

Cement stabilization is one of the chemical stabilization techniques carried out to improve sabkha soil engineering properties. Cement can be mixed with sabkha at natural water content. However, there is a lack of information concerning the dynamic properties of cemented sabkha. Therefore, this study's primary purpose is to determine the dynamic properties of cemented sabkha, at cement content of 5% and 10%, which satisfied static requirements and compare it with untreated sabkha in literature. The tests were carried out using the cyclic triaxial test at several effective stresses and cyclic stress ratios (CSR). The averages of shear modulus of cemented sabkha of 5% cement are 38, 32, and 21 MPa for cyclic stress ratio of 0.15, 0.35, and 0.65, respectively; they are 85, 45, and 43 MPa for 10% cement. Furthermore, the averages of damping of 5% cement are 0.03, 0.016, and 0.014 for CSR of 0.15, 0.35, and 0.65, respectively; they are 0.027, 0.012, and 0.01 for 10% cement. The results indicate that the increasing cement content to sabkha from 5 to 10% decreases the shear strain ratio by 0.05, 0.04, and 0.22 for CSR of 0.15, 0.35, and 0.65, respectively. For CSR of 0.15, the change in cement content from 5 to 10% leads to increased shear modulus by 1.4 to 3 times of shear modulus of untreated sabkha; the shear modulus ratio of cemented sabkha to shear modulus to sabkha increases with the increasing number of cycles. The cement content of 5 and 10% leads to a decrease in the normalized damping ratio of cemented sabkha to damping ratio of sabkha with a range from 0.55 to 0.85. [ABSTRACT FROM AUTHOR]

The article is devoted to the new application of number-theoretic transforms. Representing number systems by these transforms allows us to create fundamentally new and efficient algorithms for factoring numbers and to calculate period of the exponential function and of the discrete logarithm. The factorization algorithm allows us to decompose any finite product into factors in one run, it is an exact test of number simplicity. This algorithm is based on representing number systems by a number-theoretic transforms and has no analogs in the world since it uses only simple arithmetic operations. Properties of number simplicity or other number properties are not applied. Thus, number factoring and calculations of the exponential function period and of the discrete logarithm are simple arithmetic operations that are performed in a finite time and belong to the complexity class P. [ABSTRACT FROM AUTHOR]

A lead free polycrystalline double perovskite-based ceramic oxide Ca2BiNbO6(CBNO) was synthesized by the conventional solid state reaction route. Emergence of a new single-phase double perovskite structure exhibiting cubic phase with space group fm-3 m was confirmed through the room temperature XRD analysis. Particle size of 34.29 nm was obtained using Scherrer's formula. Different electrical parameters such as complex impedances, modulus, dielectric (εr and tanδ) and conductivity were recorded carefully by the LCR analyzer for a wide range of temperatures (25–500 ø°C) and frequencies (100 Hz–5 MHz), respectively. Large room temperature dielectric constant with a NTCR property was investigated. The ferroelectric nature with a transition temperature above 300 °C was analyzed from the study. The thermal dependent conductivity fitted curve satisfies the Arrhenius law and leads to a calculated activation energy of 0.0597 eV. The obtained result promotes this new material to be a favorable candidate to uses in smart and modern electronic device applications. [ABSTRACT FROM AUTHOR]

The mechanical characterization of brain tissue has been generally analyzed in the frequency and time domain. It is crucial to understand the mechanics of the brain under realistic, dynamic conditions and convert it to enable mathematical modelling in a time domain. In this study, the compressive viscoelastic properties of brain tissue were investigated under time and frequency domains with the same physical conditions and the theory of viscoelasticity was applied to estimate the prediction of viscoelastic response in the time domain based on frequency-dependent mechanical moduli through Finite Element models. Storage and loss modulus were obtained from white and grey matter, of bovine brains, using dynamic mechanical analysis and time domain material functions were derived based on a Prony series representation. The material models were evaluated using brain testing data from stress relaxation and hysteresis in the time dependent analysis. The Finite Element models were able to represent the trend of viscoelastic characterization of brain tissue under both testing domains. The outcomes of this study contribute to a better understanding of brain tissue mechanical behaviour and demonstrate the feasibility of deriving time-domain viscoelastic parameters from frequency-dependent compressive data for biological tissue, as validated by comparing experimental tests with computational simulations. [ABSTRACT FROM AUTHOR]

We focus on two topics that are related to moduli of elements in partially ordered vector spaces. First, we relate operators that preserve moduli to generalized notions of lattice homomorphisms, such as Riesz homomorphisms, Riesz* homomorphisms, and positive disjointness preserving operators. We also consider complete Riesz homomorphisms, which generalize order continuous lattice homomorphisms. Second, we characterize elements with a modulus by means of disjoint elements and apply this result to obtain moduli of functionals and operators in various settings. On spaces of continuous functions, we identify those differences of Riesz* homomorphisms that have a modulus. Many of our results for pre-Riesz spaces of continuous functions lead to results on order unit spaces, where the functional representation is used. [ABSTRACT FROM AUTHOR]

The damping properties of as-cast and austempered Al-alloyed ductile iron produced by rotary furnace melting process and sand casting technique were investigated. Two Al-alloyed ductile irons, which contain 2.29 wt% Al and 3.02 wt% Al, were produced and test samples were machined, followed by heat treatment process. The samples were subjected to both conventional single step and two-step austempering processes. The microstructure of the Al-alloyed ductile irons, after chemically analysed, was characterized using scanning electron microscopy, while the storage modulus, loss modulus and damping capacity were evaluated using a dynamic mechanical analyser of model DMA 242E (Artemis) with NETZSCH format, using three-point bending mode procedure in accordance with ASTM E756-05. It was found that the ausferrite structure of the Al-alloyed ductile iron exhibited improved damping capacity than the pearlite-based Al-alloyed ductile iron of the same composition. Also, the two-step austempered Al-alloyed ductile iron yielded more improved damping capacity values of 0.23194 (1 Hz) and 0.23351 (5 Hz), respectively, at room temperature than the as-cast ductile irons investigated in this study. [ABSTRACT FROM AUTHOR]

This paper is aimed at studying the thermal properties of poly(lactic acid), PLA with different plasticizers. Plasticized PLA was obtained by mixing and extruding PLA with 20 mass% of neat cardanol, epoxidized cardanol acetate (ECA) and poly(ethylene glycol) (PEG) 400. The glass transition of completely amorphous samples, melting and crystallization behavior of plasticized PLA were analyzed by differential scanning calorimetry. Results obtained show that, below Tg, a higher enthalpy relaxation occurs for PLA plasticized by cardanol derivatives. This is indicative of a faster mobility of PLA chains below Tg, when cardanol derivatives are used as plasticizers. On the other hand, an opposite behavior was observed for the crystallization studies. In facts, a much faster crystallization was found for PLA plasticized by PEG, which in turn indicates a much higher mobility of PLA chains above Tg compared to PLA plasticized by cardanol derivatives. Mechanical properties obtained on completely amorphous samples show that PLA plasticized by ECA is characterized by lower modulus, which is indicative of a more efficient plasticization. On the other hand, the thicker crystals formed during crystallization of PLA plasticized by ECA involve a more relevant increase in the modulus in semicrystalline samples. [ABSTRACT FROM AUTHOR]

Sodium silicate is one of the common alkali activators of geopolymers. The modulus, concentration and dosage of sodium silicate have significant effects on the activation of fly ash, the strength and microstructure of geopolymer. In this paper, unconfined compressive strength test, X-ray diffraction analysis (XRD), Fourier transform infrared light (FTIR), 29Si nuclear magnetic resonance (29Si NMR), scanning electron microscope and energy disperse spectroscopy (SEMEDS), and physisorption experiment (BET) were carried out to study the effects of the sodium silicate modulus and dosage on the mechanical property and microstructure of fly ash-based geopolymer. The results indicated that the main product of the geopolymer activated by sodium silicate was hydrated sodium aluminosilicate (N-A-S-H). When modulus value decreased and meanwhile dosage of sodium silicate increased, the reorganization and polymerization of gel products were accelerated so that the integrity and continuity of the microstructure of geopolymer were improved, and then the strength increased. When the modulus of sodium silicate was 3.28, the maximum value of the strength was at the dosage of 10%. According to this study, it was investigated that modulus value and dosage of sodium silicate had obvious influence on the alkali- activated reaction of fly ash, which can provide an engineering reference for the special soil solidification with geopolymers. [ABSTRACT FROM AUTHOR]

Tandon–Weng model based on Mori–Tanaka idea for tensile modulus of conventional composites is currently used for various polymer nanocomposites, but some complex terms in this model may limit the calculations. In this article, this model is simplified and developed for ternary polymer nanocomposites containing layered and spherical nanofillers. The calculations of developed model are compared with the experimental results and the trends between experimental data and the predictions are explained. The developed model shows that some parameters such as tensile modulus of nanoparticles cannot significantly affect the tensile modulus of binary and ternary nanocomposites, due to its very high level. [ABSTRACT FROM AUTHOR]

Gyeongju bentonite is a Ca-bentonite and a highly compacted buffer material primarily considered in Korea, as a part of an engineered barrier system (EBS) of high-level radioactive waste (HLW) repository. During the repository lifetime, the buffer material should guarantee the safe disposal of HLW against any external mechanical impact, including seismic activity. Therefore, the dynamic deformation properties of buffer material is crucial to validate its lifetime effectiveness and performance. Even though there are some researches to investigate the dynamic properties of the bentonite buffer, there has been no researches for the Korean bentonite buffer. For this reason, the paper aims to evaluate the dynamic properties at small-strain of Gyeongju bentonite and correlate the small-strain deformation properties with unconfined compressive strength using seismic and static laboratory tests. Three sets of compacted cylindrical bentonite specimens with varying dry densities (1.50 g/cm3 to 1.77 g/cm3) were produced using a cold isostatic pressing technique under three different pressing loads. Free-free resonant column (FFRC) tests and unconfined compressive (UC) tests were performed. The FFRC tests measured deformation properties at small strain, including unconstrained and constrained compression velocities, Young's modulus (Emax), constrained modulus (Max), material damping ratio (Dmin), and Poisson's ratio. The UC tests evaluated the compressive strength and secant modulus (E50) at large-strain. In this study, it was found that the deformation properties (Emax and Mmax) and unconfined compressive strength increase with the increase in a design rage of dry density. Poisson's ratio measured at constrained boundary yields relatively constant value close to 0.4 for specimens at a range of dry density higher than 1.5 g/cm3. In addition, it was found that the elastic moduli have an almost linear relationship with the unconfined compressive strength. Finally, empirical equations between elastic moduli and unconfined compressive strength for Gyeongju compacted bentonite are proposed for a Koeran design guideline. [ABSTRACT FROM AUTHOR]

A general model was developed to predict the temperature-dependent modulus and yield strength of different thermoplastic polymers. This model, which depends on only two parameters with clear and specific physical meanings, can describe the temperature-dependent modulus and yield strength of thermoplastic polymers over the full glass transition region. The temperature-dependent modulus and yield strength of three thermoplastic polymers were measured by uniaxial tension tests over a temperature range of 243–383 K. The predictions showed excellent agreement with the experimental data. Sensitivity analysis of model input parameters showed negligible effect on the present general model. The universality of the present general model was further validated, showing excellent agreement with published experimental data on other thermoplastic polymers and their composites. [ABSTRACT FROM AUTHOR]

This paper presents the fabrication and electrical characterization of a lead-free polycrystalline complex electronic material Ba0.8Sr0.2(Zr0.1Ti0.8Ce0.1)O3 (abbreviated as BSZTCO) using standard experimental techniques. The phase identification of the material, determined using X-ray diffraction data, depicts the formation of a multi-phase system. The various electrical parameters were obtained at different frequencies (102–106 Hz) and temperatures (20–500 °C) using the phase-sensitive meter and found interesting results. Study of the micrograph of natural surfaces of the sample suggests that the ceramic sample has been formed with high density grain growth (without any cracks or voids). The transport properties and dielectric relaxation characteristics of the material have been studied using modulus and impedance spectroscopy techniques. Temperature dependence of conduction behavior (Nyquist plot) confirms the presence of bulk and grain boundary effects in the material. The charge transfer by hopping dominates the electrical transport process of the material as revealed from conductivity analysis. The dielectric relaxation of the material is studied using a complex modulus spectrum depicting non-Debye type relaxation. [ABSTRACT FROM AUTHOR]

A simple methodology is suggested to examine the roles of interphase characteristics in the shear, bulk and Young's moduli of polymer nanocomposites containing spherical nanoparticles such as SiO2 and CaCO3. A core-shell structure is presumed for nanoparticles and surrounding interphase, and then the shear and bulk moduli of supposed particles are calculated. Subsequently, simple equations predict the different moduli of a composite containing a polymer matrix and supposed particles. The absence of interphase regions between the polymer matrix and nanoparticles underestimates the moduli of nanocomposites, but the calculations show good agreement with the experimental data assuming the proper levels for thickness and moduli of interphase regions. The Poisson ratio of polymer matrix vm differently affects the shear, bulk and Young's moduli of nanocomposites. The variation of vm unimportantly changes the shear modulus, while vm significantly affects the bulk modulus. Thick and high-modulus interphase regions cause the positive effects on the shear, bulk and Young's moduli of nanocomposites. According to the present results, the properties of the polymer matrix, nanoparticles and interphase introduce a wide variation in the bulk modulus, while cause moderate and slight changes in the Young's and shear moduli of nanocomposites, respectively. [ABSTRACT FROM AUTHOR]

Magnetoelectric composites combining ferromagnetic cobalt ferrite (CFO) and ferroelectric barium titanate (BT) are prepared using conventional solid-state reaction. Dielectric measurements reveal that CFO and CFO-BT composites exhibit Maxwell–Wagner polarization and temperature-dependent relaxation originating due to the presence of ions/defects vacancies. Prominently, CFO-30%BT composite showed an unexpected low dielectric loss ≈ 0.5 above 1 kHz and has potential for device application. Impedance spectroscopy confirms the thermally activated relaxation mechanism and high impedance behavior in the samples. Modulus analysis affirms the statistically distributed non-Debye-type behavior existing in CFO-BT composites. The electric conductivity takes place via correlated barrier hopping in CFO and CFO-10BT composite and overlapping large polaron tunneling in CFO-30BT composite. The addition of BT in CFO initiates the structural modification and results in conductivity cross-over with improved conductivity. These results are useful for exploring devices based on CFO-BT composites. [ABSTRACT FROM AUTHOR]

We construct a linear operator R, between two Banach lattices, such that R has a modulus which does not satisfy the Riesz–Kantorovich formula, thereby answering a long-standing question in the theory of regular operators. [ABSTRACT FROM AUTHOR]

Converter steel slag, currently underutilized crystalline metallurgical residue, was investigated for use as a precursor for alkali activation. Water glass solution with various moduli (0.5, 1.0, 1.5 and 2.0) was used at the same Na2O dosage of 4% in order to investigate effect of modulus on hydration. Pure cement paste with the same ratio of water to binder was selected as the control sample. Results show that modulus has a significant impact on the hydration and mechanical strength development of alkali-activated steel slag. Similar to pure cement paste, alkali-activated steel slag paste has C–S–H gel and Ca(OH)2 as its main hydration products. However, alkali-activated steel slag pastes have lower hydration heat and fewer amounts of hydration products. Additional silicate has a retarding effect on the hydration of steel slag. Hydration heat, Ca(OH)2 contents and non-evaporable water contents reduce with increasing modulus. In addition, high silicate modulus fines the pore structure and improves compressive strength of the hardened paste. [ABSTRACT FROM AUTHOR]

This study focused on rheological and mechanical properties of poly(vinylidene fluoride) nanocomposites incorporated with functionalized graphene nanoplatelets and hydroxylated titanium dioxide. Mechanical properties of the ternary composites were improved with a slight reduction in damping coefficient compared to the pure polymer and graphene binary composites. The storage modulus of the ternary composites significantly increased from about 67.5 Pa for the pure polymer to 3.24 × 105 Pa and 3.49 × 105 Pa at 0.1 rad/s for 6.67 wt% graphene composites containing 10 wt% and 20 wt% titania respectively. All ternary composites showed higher tensile strength and Young modulus compared to the pure polymer. Strong bonding between the polymer and co-fillers with a reduction in interfacial slipping in the ternary composites resulted in their lower damping factor and higher strength compared to their counterparts. The composite samples were prepared by solution and melt mixing methods. The scanning electron microscope was used to examine the samples' morphology and dispersion of the co-fillers in the matrix. Such composites can find applications in automobile and aerospace industries where materials with good strength and noise or vibration absorption capability are required. [ABSTRACT FROM AUTHOR]

Cesium–zinc orthophosphate (CsZnPO4) was prepared by a solid-state method. X-ray powder diffraction at room temperature confirmed the phase formation of the synthetized compound in the monoclinic system (P21/a space group). Infrared and Raman spectroscopies showed the presence of PO43− anion and its vibrations. Regarding the differential scanning calorimetry, three reversible phase transitions were revealed. The first is of a second-order type located at T1 = 520/503 K (heating/cooling), while the second and the third ones are of a first-order type located at T2 = 544/520 K (heating/cooling) and T3 = 585/577 K (heating/cooling). The detected phase transitions with calorimetric measurements were confirmed by average normalized change (ANC) and electrical conductivity study. The conduction of the studied sample is assured by Cs+ ions' hopping in tunnels and its mechanism was discussed. [ABSTRACT FROM AUTHOR]