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A novel UV-curable hyperbranched polyester-urethane-acrylate (PUA) resin was successfully synthesized using citric acid as a core bio-based material and ester-urethane-acrylate linkage as the arm and was applied on both wood and metal substrates. Citric acid was employed as a functionality-enhancing bio-based monomer for coating applications. This resin (PUA) was synthesized from citric acid (CA)-based polyester-polyol (CAP) and subsequently reacted with isophorone diisocyanate (IPDI) and end-capped with 2-hydroxyethylmethacrylate (HEMA) to form a tetra-functional acrylate precursor (UCAP). Fourier-transform infrared spectroscopy (FTIR), proton nuclear magnetic resonance spectroscopy (1H-NMR) and gel permeation chromatography (GPC) were used to characterize the citric acid-based polyester-urethane-acrylate (UCAP). This oligomer was formulated with a reactive diluent and a photoinitiator (UCAP PUA), applied on both wood and metal substrates and cured under UV-radiation. The mechanical, chemical and thermal properties of the coated substrates were investigated and compared to a commercial urethane acrylate (CUA). The mechanical properties such as crosscut adhesion, pencil hardness, impact strength and flexibility showed comparable results. Even though the chemical resistance and free film properties of the synthesized urethane acrylate (UCAP) were found to be inferior, the thermal properties were observed to be superior. [ABSTRACT FROM AUTHOR]

[Display omitted] Inorganic nitrate is an indispensable nutrient that has been used in experimental studies for the prevention and treatment of several diseases. However, the short half-life of nitrate limits its clinical application. To increase the usability of nitrate and overcome the challenges of traditional combination drug discovery through large-scale high-throughput biological experiments, we developed a swarm learning-based combination drug prediction system that identified vitamin C as the drug of choice to be combined with nitrate. Employing microencapsulation technology, we used vitamin C, sodium nitrate, and chitosan 3000 as the core materials to prepare a nitrate nanoparticle, which we named Nanonitrator. The long-circulating delivery ability of nitrate by Nanonitrator significantly increased the efficacy and effect duration of nitrate in irradiation-induced salivary gland injury, without compromising safety. Nanonitrator at the same dose could better maintain intracellular homeostasis than nitrate (with or without vitamin C), emphasizing its potential for clinical use. More importantly, our work provides a method for incorporating inorganic compounds into sustained-release nanoparticles. [ABSTRACT FROM AUTHOR]

Potassium carbonate was tested as novel information for producing carbonaceous materials from jute cores. Two quadratic models have been developed for both answers to link the preparatory parameters: activating temperatures, molar ratio, and incubation time. The RSM and ANN models were used to improve the processing conditions to maximise the quantities of iodine and methylene blue penetration. The best charcoal was obtained using 900°C activating temperatures, a 1.5 molar ratio, and a 4-hour activating time. This resulted in iodine and methylene blue absorption of 1260.07 mg/g and 369.21 mg/g, respectively. It was discovered that the K2CO3-based pyrolysis process might be anticipated to become a safe yet incredibly efficient process of making activated carbons with a very well-defined and monocultural porous structure. Even though the precise emphasis given to K2CO3 is unknown at the moment, given the creation of K2C3O4 just after evolvement with one additional molarity of CO at approximately 870°C, these same porous and papule responses begun by K2CO3 stimulation might be temporarily posited to be quite comparable to an initiation action needed to make progress by K2C3O4. The influence of control parameters was examined in this study using variance analysis like the ANOVA test. Furthermore, the response surface (RSM) and artificial neural networks (ANN) are employed to improve the output results while optimising the methylene blue and iodine qualities. Consequently, the experimental findings correlate well with the statistics. [ABSTRACT FROM AUTHOR]

The work is dedicated to revealing the structural features of coals with different ranks, such as anthracites, metaanthracite and graphite, that determine their ability to crush and form fine dust. For this purpose, a combination of various nanoindentation techniques and Raman spectroscopy was used. The mechanical behavior of the selected coals was investigated by cyclic nanoindentation with increasing peak load and quasi-static loading. The alteration of the mechanical properties was studied by analysis of elastic moduli and damage indices Rw. Three groups of coals were identified based on their propensity to crushing during cyclic nanoindentation. Coals assigned to the first and second groups are characterized by local destruction in the contact zone with the indenter and the formation of a core of crushed material. Coals assigned to the third group are characterized by bulk destruction (outside the zone of contact with the indenter). In general, the ability of coals to fracture under mechanical loading decreases in the series of metamorphism due to microscale compaction of vitrinite matter. In the series of anthracite, metaanthracite and graphite, it is established that the coal matter compaction takes place for the anthracite and metaanthracite, whereas graphite reveals rather different behavior due to abrupt change of its structure. The ratios between the amorphous and crystalline phases of carbon (S) were determined by deconvolution of coals Raman spectra. The propensity of coals to crushing (a damage index Rw) increases with growth of the proportion of amorphous carbon in the coal matter. For the considered coals and metaanthracite, it is established that the proneness to destruction outside the contact zone with the indenter is determined by the ratio of amorphous and crystalline carbon of 1 and higher. When S parameter is lower than 1, the coals are being crushed only in the zone of contact with the indenter. [ABSTRACT FROM AUTHOR]

Diphenylanthracene (DPA) and its derivatives are promising semiconducting materials for p‐type organic‐field‐effect transistors (OFETs). In this study, to develop n‐type semiconducting materials with an anthracene core, pentafluorobenzene was introduced into anthracene by C−H direct arylation, enabling the synthesis of various bis(pentafluorophenyl)anthracene (DPA−F) derivatives. The high reactivity of the pentafluorobenzene C−H bond allows direct arylation for synthesizing DPA−F derivatives in a single step. The introduction of strong electron‐withdrawing pentafluorophenyl groups provides the anthracene derivatives with n‐type semiconducting properties, in contrast to the p‐type properties of the parent DPAs. Among the synthesized compounds, 2,6‐bis(pentafluorophenyl)anthracene shows a high electron mobility of 0.12±0.02 cm2/Vs and an on/off ratio>106 in OFETs. The high crystallinity results in the smooth electron transport. This study provides a facile synthetic method for n‐type semiconducting materials and insights into the molecular design of the positional effects of aromatic substituents on anthracene. [ABSTRACT FROM AUTHOR]

The choice of materials for cores of electrotechnical devices is currently related to energy saving and global warming problems. Nanocrystalline alloys are emerging as materials for cores in these devices in addition to amorphous materials already commonly used due to their better magnetic properties at high operating frequencies. The thermal stability of the magnetic properties of cores is also an important criterion. Keeping these criteria in mind, a study of microstructure and magnetic properties was carried out in this work, and FeCoNbBCu-type material was selected for use as the core of a choke operating in a DC/DC converter in interleaved topology. On the basis of the conducted studies, it was found that good magnetic properties and the best thermal stability were shown by Fe58Co25Nb3B13Cu1 alloy. Using RALE software, the technical parameters of the choke core were determined and compared with the same parameters for a choke core made of FINEMET-type alloy. [ABSTRACT FROM AUTHOR]

Recently, metal–organic frameworks (MOFs) as the cathode materials for aqueous zinc‐ion batteries (ZIBs) received growing attention. Herein, a novel MOF, Ni‐Ndi‐trz (Ndi‐trz=2,7‐di(4H‐1,2,4‐triazol‐4‐yl)benzo[lmn][3,8]phenanthroline‐1,3,6,8(2H,7H)‐tetraone) was synthesized through a solvothermal method. Its rational design using a naphthalene diimide (Ndi) core allowed the formation of a four‐fold interpenetrated pcu (primitive cubic) topology. The as‐synthesized Ni‐Ndi‐trz is highly stable over a wide pH range (0–12) for 30 days, which is critical to ensure the decent cyclability of zinc‐ion batteries (ZIBs). When used as the cathode material of ZIBs, it shows a high initial specific capacity of 90.7 mAh g−1 and excellent cycling stability. Remarkably, three‐electrode system tests, ex situ FTIR, UV/Vis and XPS spectra revealed that the Ndi core of Ni‐Ndi‐trz undergoes a reversible interconversion between the keto and enol forms when interacting with Zn2+ ions. This work may shed light on the feasibility of designing novel MOFs and exploring their mechanisms for zinc ion batteries. [ABSTRACT FROM AUTHOR]

The preparation technology of sustained release is a significant value of fragrance microcapsules. This article used quaternary ammonium chitosan (HACC) with antibacterial properties as the shell material. To research the factors affecting the density, encapsulation ratio and sustained‐release of the shell material of the coated fragrance microcapsules. According to the in‐situ polymerization method, fragrance microcapsules were prepared with aldehyde fragrance 7328 as the core material, TiO2 modified HACC as the shell material and glutaraldehyde as the crosslinking agent. During preparation, the effects of emulsification speed, pH and core‐shell ratio on the encapsulation ratio were explored. The results showed that under the conditions of the core‐shell ratio of 3:1 and emulsification speed of 1000 rad/min, when the shell material is modified with TiO2 and kh550, the encapsulation ratio can be reached 71.74%, which was increased by 41.5% compared with the unmodified microcapsules. And the sustained‐release time can last as long as 29 days, which was 18 days higher than that of unmodified microcapsules. [ABSTRACT FROM AUTHOR]

Baling cellulosic biomass into round bales is an effective way to reduce the cost of storage and transportation. To improve the quality of bales and reduce the baling energy consumption, this paper introduces the steel roller layout parameters of the round baler into the biomass baling process. Alfalfa was used as an experimental material for five levels pitch value of roller circumferential layout baling experiments. The results showed that the introduction of chamber non-roundness (pitch value of roller circumferential layout) destroyed the formation of the entanglement high density ring cylindrical shell lamination of the outer layer of bales, which was beneficial to the compression of bales core material. When the pitch value was 30 mm, the maximum baling pressure, radial pressure transfer loss, and the baling energy consumption of baler were reduced by 30.4%, 33.4%, and 13.7%, respectively. When the pitch value was 60 mm, the relaxation ratio and radial density difference were reduced by 6.3% and 35.8%, respectively, and the radial density uniformity of alfalfa bale was increased by 32.0%. The experimental results provide a theoretical basis and technical support for the chamber structural optimization design of the round baler. [ABSTRACT FROM AUTHOR]

The necessary conditions are established for the thicknesses of two layers of the planar absorbing structure at which zero reflectance can be achieved. Using these conditions, a numerical procedure was developed for finding the thicknesses of three layers of the structure, which makes it possible to achieve close to zero values of the reflectance and transmittance for the chosen wavelength. This made it possible to propose a method for designing narrow-band absorbers based on such structures. [ABSTRACT FROM AUTHOR]

Faults are composed of a damage zone and a fault core with wear material that has accumulated during sliding. Fault zone width and structural complexity have been suggested as key factors that dictate the stability of fault slip and the transition from stable to unstable motion. Here we address the role of fault rock wear rate and the presence of gouge on the stability of frictional sliding. We performed biaxial shear experiments on quartz‐rich bare rock surfaces having different resistances to abrasion (i.e., wear production with slip), as well as simulated quartz gouge. To characterize the influence of shear displacement on fault stability, constant velocity and velocity step experiments were performed to displacements up to 30 mm. Mechanical data are analyzed within the rate‐and‐state framework, and integrated with post‐mortem microscopic analyses of the samples. For initially bare surfaces a shear displacement threshold is required to transition from stable to unstable sliding. Stick‐slip events (laboratory earthquakes) evolve systematically as a function of fault slip. Shear displacement has a clear effect on the rate‐and‐state parameters (a‐b) and Dc. For all our tests, (a‐b) decreases with increasing shear displacement, implying enhanced velocity weakening and potential unstable behavior for larger fault slip. For high wear rates and simulated gouge, Dc decreases with increasing slip. However, for low wear rate faults, changes in Dc are negligible. Our results demonstrate that, fault stability varies systematically with fault slip and in particular that shear displacement and strain localization are dominant parameters controlling fault stability. Plain Language Summary: Large earthquakes mainly occur on faults having large cumulative slip. In the field, fault structure consists of a fault core made of wear product (rock flour) that is surrounded by fractured rocks (damage zone). Most of laboratory studies on fault stability, that is, the capability of fault to nucleate earthquake, consider faults either as only intact rock interfaces or wear product only. Here, we address the role of fault rock wear rate (wear development with slip) and the presence of fault gouge on the mode of frictional sliding (stable sliding vs. earthquake). Three fault systems were tested in the laboratory: intact rock surfaces having a low wear rate, intact rock surfaces having a high wear rate and wear product alone. We found that for all the tested faults, earthquake nucleation requires a certain amount of slip. Microstructural analyses of the fault after the experiment show that cumulative slip favors localization of the deformation necessary for earthquake nucleation. We show that the fault stability is not constant in time and space but depends on the fault history (cumulative displacement, shear localization, presence or absence of gouge). Key Points: Laboratory investigation of fault stability with varying wear rateShear displacement has a dominant impact on fault stabilityIndependently of the fault wear rate, the rate‐and‐state stability parameters evolve continuously with shear displacement [ABSTRACT FROM AUTHOR]

Abstract—This paper offers a general approach to the modelling of the wellbore stress state in the Bazhenov formation. In modelling, strata are presented as transversely isotropic objects with a set direction of the anisotropy axis that does not coincide with the vertical line. The paper also presents results of the laboratory Bazhenov formation core analysis. The analysis of core materials yielded correlation dependences for reconstructing stress-strain parameters of a transversely isotropic medium in selected wells. Parameters of the rock anisotropy were analyzed on the basis of standard and non-standard laboratory tests. The solution of the stress state problem in a deformation bounded medium was used to suggest an algorithm of calculating the components of the regional stress state along the well path. RN-SIGMA software tools were used to construct borehole stability models for wells penetrating anisotropic rocks. The effect of the anisotropy of elasticity on a safe drilling mud density window is demonstrated. The results of the calculations show that the anisotropy effects are crucial for calculating a safe drilling window. Examples are given to demonstrate potential effects of the anisotropy in image interpretation as well as in selecting horizontal wellbore drilling directions. [ABSTRACT FROM AUTHOR]

In this paper, free vibration, modal and stress state analyses of honeycomb sandwich structures with different boundary conditions was investigated and major factors affecting the sandwich frequencies and stiffness due to material or parameter changes were determined. The representative volume element (RVE) method used in this work were analytically and numerically validated by comparing the obtained results to those available in literature. Firstly, unit cell method was used to capture the entire effects of different parameters on the free vibration of honeycomb sandwich structure in ANSYS. This study analyzed the natural frequencies of honeycomb sandwich structures with different core materials combination. The effects of foil thickness, boundary conditions, materials selection, density and presence of crack on sandwich structure were taken into consideration and examined. The proposed core had an inbuilt shaped reinforcement with different materials f [ABSTRACT FROM AUTHOR]

Electrospinning is considered to be an efficient method to prepare piezoelectric thin films because of its ability to transform the phase of the polymers. A core-sheath structure can endow fibers with more functions and properties. In this study, fibers with a core-sheath structure were prepared using polyvinylidene fluoride (PVDF) included with nanoparticles (NPs) as the shell layer and polycaprolactone (PCL) as the core layer. Their mechanical and piezoelectric properties were studied in detail. During the course of the electrospinning process, PVDF was demonstrated to increase the amount of its polar phase, with the help of nanoparticles acting as a nucleating agent to facilitate the change. PCL was chosen as a core material because of its good mechanical properties and its compatibility with PVDF. Transmission electron microscope (TEM) assessments revealed that the fibers have a core-sheath structure, and shell layers were loaded with nanoparticles. Mechanical testing showed that the core layer can significantly improve mechanical properties. The XRD patterns of the core-sheath structure fibers indicated the β phase domain the main component. Piezoelectric testing showed that the doped nanoparticles were able to enhance piezoelectric performances. The increases of mechanical and piezoelectric properties of core-sheath structure fibers provide a feasible application for wearable electronics, which require flexibility and good mechanical properties. [ABSTRACT FROM AUTHOR]

With the development of science and technology, the function of waterborne coatings has been advanced to a higher standard, which requires researchers to innovate and expand the research on them. Aloe-emodin is a natural material with antibacterial properties. Applying its antibacterial effect to the coating can enrich its function and meet the diversified needs of consumers. In this study, the urea-formaldehyde resin was used as the wall material and the aloe-emodin as the core material to prepare the microcapsules. The coating rate, yield, and morphology of the microcapsules were characterized. Through an orthogonal experiment and a single factor experiment, the optimization scheme of microcapsule preparation was explored. The results indicated that the optimum preparation process of aloe-emodin microcapsules was as follows: the mass ratio of core material to wall material was 1:15, the molar ratio of urea to formaldehyde was 1:1.2, the temperature of microencapsulation was 50 °C, and the stirring speed of microencapsulation was 600 rpm. On this basis, the aloe-emodin microcapsules with 0%, 1.0%, 3.0%, 6.0%, 9.0%, and 12.0% contents were added to the waterborne coating to prepare the paint films, and their influence on the antibacterial and optical properties of the waterborne paint films was explored. The results demonstrated that the aloe-emodin microcapsules had antibacterial activity. When the content was 6.0%, the comprehensive performance of the film was better. The antibacterial rate of the film against Escherichia coli was 68.1%, and against Staphylococcus aureus it was 60.7%. The color difference of the film was 59.93, and the glossiness at 60° was 7.8%. In this study, the microcapsules that can improve the antibacterial performance of water-based coatings were prepared, which can expand the application of water-based coatings and provide a reference for the study of the functionalization of water-based coatings. [ABSTRACT FROM AUTHOR]

In this paper, nanosilver solution was used as an antibacterial agent to prepare antibacterial microcapsules. The mass ratio of the core material to the wall material (Wcore: Wwall), the emulsifier's hydrophilic–lipophilic balance (HLB) value, the mass ratio of ethanol to the emulsifier in solvent (Wcore: Wemulsion), and the rotational speed (r/min) were used to develop the four-factor, three-level orthogonal experiment, which was meant to investigate the most significant factors and the optimum process preparation parameters impacting the coating rate and yield of microcapsules. It was used to make an antibacterial coating that was applied to the surface paint film of a glass substrate and andoung wood, and it was mixed to the water-based primer with a content of 4%. Analyses of the mechanical, optical, and bactericidal characteristics were conducted. The micromorphology of the nanosilver solution microcapsules is influenced by the emulsifier's HLB value. The color difference of the antibacterial coating film decreased with increasing emulsifier HLB value; however, the coating film's gloss remained largely suitable. Additionally, the coating film's transparency and tensile strength both decreased. It had minimal impact on the paint film's surface hardness, but the adhesion and tensile strength showed a noticeable downward trend. The surface of the paint film was rough. Escherichia coli and Staphylococcus aureus were resistant to the antibacterial characteristics of the water-based primer film when it was combined with antibacterial nanosilver solution microcapsules by 80.7% and 74.55%, respectively. The coating film's antibacterial properties were applied to the surface of the andoung wood, which were 75.7% and 71.0%, respectively, and somewhat decreased. In order to successfully inhibit bacteria, the nanosilver solution microcapsules were added to waterborne coatings. This ensures both the outstanding performance of the coating film and the effectiveness of the antibacterial effect. It expands the application prospects of antibacterial microcapsules in coatings. [ABSTRACT FROM AUTHOR]

Castings are near-net-shape components that are almost always machined to produce the final product. Dimensional variation is driven by casting geometry, dimensional accuracy of mold and core boxes, variation in the mold and core material properties, and casting process. This work examines the shrink behavior of stepped tubular castings with varying wall thicknesses. Dimensional shrink magnitudes are related to processing factors (core type, resin content, and knock-out time) and geometric factors (section size, inner/outer diameter, location relative to parting line) using a full-factorial design of experiment. Shrink factors, a scaling number used in building tooling to obtain the correct size component, are determined as a function of the tube inner and outer diameters as well as length. [ABSTRACT FROM AUTHOR]

Sol–gel and two step polyacrylamide gel methods were used for the preparation of three systems NiFe2O4 (1:1, 1:2, 1:3, 2:1 and 3:1), ZnxNi1−xFe2O4 (x = 0–0.8) and CozCdyZnxNi(1−x−y−z)Fe2O4 (x + y + z = 0–0.75) nanocomposites (1–3). After the sintering process, electrochemical responses of NiFe2O4 (NFO) samples have been studied to analyze the effect of Zn2+, Cd2+ and Co2+ ions on dielectric and magneto-electric properties. Ni2+ and Fe3+ ions have considerable influence on the relative permittivity εr′ values from 9.57 × 103 to 5.29 × 103 at lower frequency. In Znx@Ni1−xFe2O4 (x = 0.4) sample, a small decrease in the ac-conductivity showed higher ionic conductivity than other specimens. The decrease in magneto-dielectric (MD) and increase in magneto-conductivity (MC) responses were observed at higher frequencies between 1.5 and 2 logf for samples x = 0.4 and x + y + z = 0.45. The enhancement in magneto transport property (65.2–432%) of CozCdyZnxNi(1−x−y−z)Fe2O4 at 0.01 T confirms ferromagnetic behavior. A novel compound system with high magneto-electric response can develop the sensitivity and energy conversion of magnetic core materials. [ABSTRACT FROM AUTHOR]

This study presents the results of full-scale field tests of embankments supported with wood-cored stiffened deep cement mixing (SDCM) columns and conventional DCM columns to highlight the superior performances of wood-cored SDCM column-supported embankment (SCSE) and to confirm that a less stiff material such as wood can be used as a core in SDCM columns. A further numerical investigation on SCSE performances is conducted. Several effects of SDCM column parameters (core pile and socket dimensions and spacing), load-transfer platform inclusion, and different core pile materials are considered and highlighted. Column-supported embankment performances consisting of embankment settlement, differential settlement, lateral movement, column bending moment, and embankment stability, are detailedly assessed and discussed. Numerical results indicate that the significant improvements of soil settlement and safety level regarding column bending failure are obtained for SCSE. However, the differential settlement of SCSE should carefully be considered. Based on cost-effectiveness, SDCM columns with small diameter core can be used to support embankments if the required deformation is not strict. It is also recommended that the wood can be used as the core in SDCM columns to support embankments instead of concrete for saving the column construction cost. [ABSTRACT FROM AUTHOR]

Gas sensors can effectively detect toxic, harmful, flammable and explosive gases with concentrations below the human olfactory limit, and have great research significance in the fields of military defense, environmental safety, medical diagnosis and so on. Among them, resistance gas sensor is widely used because of its low cost and universal suitability for civil gas detection. Gas sensing material is the core of gas sensor, and it is very important to design and synthesize suitable gas sensing material for developing high performance gas sensor. Based on the brief introduction of gas sensor, resistive gas sensor, and several traditional gas sensing materials of resistive gas sensor, this review focuses on the SnS2 gas sensing materials, a class of n-type semiconductors. The structure, properties, research status and limitations of SnS2 gas sensing materials are summarized. Several important methods to improve the performance of SnS2 gas sensing materials and SnS2-based gas sensors are summarized, including vacancy engineering, thermal activation engineering, photoactivation engineering and heterojunction engineering. The research trend of SnS2-based gas sensors is prospected. [ABSTRACT FROM AUTHOR]

Copyright of Acta Materiae Compositae Sinica is the property of Acta Materiea Compositae Sinica Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In this work, various emerging core and winding materials suitable for a high frequency planar transformer (PT) has been analyzed and compared. Core and winding materials used in a transformer has a significant effect mostly in the core and winding losses of the transformer. Emerging core materials like amorphous and nanocrystalline cores were compared against the conventional ferrite core. The results obtained showed that core losses were reduced by around 48.14% on using amorphous or nanocrystalline cores instead of the conventional ferrite cores. Typical copper and aluminum windings were also compared with emerging materials like carbon nanotube (CNT), Cu/CNT and Al/CNT. Winding losses was found to be the lowest on using CNT windings instead of metal windings like Cu or Al, or metals composite windings like Cu/CNT and Al/CNT. A winding loss reduction of about 56.2% was seen with CNT windings. Thus, it was concluded that the best possible core and winding combination was amorphous or nanocrystalline cores with CNT windings, as they give the lowest possible core and winding losses for the PT. Finite Element Analysis was carried out on a 2-kW PT operating at 100 kHz frequency, with the software Altair FLUX for the analysis. [ABSTRACT FROM AUTHOR]

A single-polarization solid-core anti-resonant fiber is proposed, and the influence of the fiber core material anisotropy of the solid-core anti-resonant fiber on polarization characteristics is investigated using the finite element method. Single-polarization guidance is achieved by using the anisotropy of optical fiber materials, which also ensures high birefringence. The numerical simulation results indicate that there are two single-polarization intervals (1210–1440 nm and 1490–1560 nm), with a maximum bandwidth of up to 230 nm, when the confinement loss difference between the two orthogonal polarizations exceeds two orders of magnitude. Specifically, when the work wavelength is 1550 nm, a polarization extinction ratio (PER) of 108 is obtained by optimizing the structure parameters. Additionally, the y-polarization fundamental mode (YPFM) can be well confined in the fiber center with a low confinement loss of 0.04 dB/m, while the x-polarization fundamental mode (XPFM) has a huge confinement loss larger than 4.65 dB/m due to the coupling with the tube mode. The proposed single-polarization solid-core anti-resonant fiber has a huge potential in applications such as laser systems, fiber-optic gyroscopes, and optical fiber communications. [ABSTRACT FROM AUTHOR]

The article analyses technologies for the formation of coatings to protect machine and equipment parts from corrosion and wear in aggressive environments. the study considers plasma electrolytic oxidation (PEO) regimes of valve metal materials on the core, microstructure, and physical and mechanical properties of oxide coatings. To solve this problem, it is promising to develop a combined technology: application of a layer of aluminium on the surface of steel parts followed by its PEO. the purpose of this work is a theoretical study of the temperature distribution in a steel cylinder covered with a layer of aluminium during PEO to substantiate the thickness of the layers of the two-layer aluminium-aluminium oxide coating. An installation for PEO and a technological process of forming a two-layer Al-Al2O3 coating on long-dimensional parts are developed. A mathematical model is created for an infinite three-layer cylinder with an internal coaxial surface cylindrical source of heat that moves at a constant speed in the radial direction deep into the aluminium layer of the cylinder. It is based on solving the boundary value problem of thermal conductivity with the condition of ideal thermal contact between the layers. During PEO, a solid oxide layer is formed, but the thickness of the unoxidized aluminium layer decreases. The thermophysical characteristics of such a cylinder are functions of both the radial co-ordinate of the cylinder and the time. During the construction of a two-layer coating, it is advisable to use the results of thermal calculations to justify the thickness of the unoxidized aluminium layer adjacent to the surface of the steel under the condition of ensuring the flow of mutual diffusion processes at the interface between aluminium and steel to increase the adhesion strength of the coating to the base due to heating by instantaneous heat sources caused by the action of electric-spark discharges in the PEO process. the thickness of the outer solid layer of aluminium oxide is chosen based on the condition of ensuring the necessary service life of machine parts for wear with a certain reservation. the results of mechanical, tribological, and corrosive cracking tests for steel samples with the developed two-layer Al2O3 coating show its high operational properties. [ABSTRACT FROM AUTHOR]

Drumlins are important bedforms of former glaciated landscapes as they demonstrate past ice‐flow directions and elucidate processes that operated at the ice/bed interface. Recently mapped drumlins and other streamlined subglacial bedforms in northeast Iceland reveal the flow‐sets of cross‐cutting palaeo‐ice streams that were active within the Iceland Ice Sheet (IIS) during and following the Last Glacial Maximum. Here we study the Bustarfell drumlin field within the Vopnafjörður–Jökuldalsheiði flow‐set. The internal architecture of two drumlins was investigated using sedimentological analysis and ground‐penetrating radar (GPR, 50 and 100 MHz) to illuminate subglacial processes that contributed to drumlin formation, as well as the history and dynamics of the IIS. On the stoss side of one of the drumlins, two subglacial traction till units were identified, separated by a thick unit of deformed glaciofluvial sand and gravel. The core of glaciofluvial material suggests that the drumlin formed around well‐drained patches (sticky spots) in the subglacial bed that retarded the ice flow locally through increased basal drag and encouraged till deposition. Furthermore, our GPR data indicate a combination of erosional and depositional processes. We suggest that the glaciofluvial sediments were deposited as small ice‐marginal fans on the Bustarfell plateau, possibly during the Bølling–Allerød interstadial, and that the drumlins were formed around these fans during a subsequent readvance during the Younger Dryas. [ABSTRACT FROM AUTHOR]

Aim: The study aimed to evaluate and compare the shear bond strength (SBS) at the interface of monolithic zirconia with zirconomer (Zr) core build-up, a new type of glass ionomer cement to monolithic zirconia with composite resin core build-up material. Setting and Design: In vitro a comparative study. Materials and Methods: A total of 32 disk-shaped samples of monolithic zirconia and two distinct core build-up materials: Zr (n = 16) and composite resin (n = 16) were used. The two components, monolithic zirconia with Zr core build-up and monolithic zirconia with composite resin core build-up, were bonded using zirconia primer and self-adhesive, dual-cure cement. The samples were subsequently thermocycled, and the SBS was tested at their interfaces. The failure modes were determined using a stereomicroscope. Data were evaluated using the descriptive analysis for mean, standard deviation, confidence interval, and independent t-test for intergroup comparison. Statistical Analysis Used: Descriptive analysis, independent t-test, Chi-square test. Results: The mean SBS (megapascals) of monolithic zirconia to Zr core build-up (0.74) was statistically significant when compared to monolithic zirconia with composite resin core build-up material (7.25) (P ≤ 0.001). Zirconomer core build-up showed 100% adhesive failure; composite resin core build-up had 43.8% cohesive, 31.2% mixed, and 25.0% adhesive failures. Conclusion: When evaluating the two core build-up materials' bindings to monolithic zirconia, Zr and composite resin core build-up showed statistically significant differences. Although Zr has been demonstrated to be the optimal core build-up material; however, additional investigation is required to determine how it bonds to monolithic zirconia more effectively. [ABSTRACT FROM AUTHOR]

Copyright of Tikrit Journal of Engineering Sciences is the property of Republic of Iraq Ministry of Higher Education & Scientific Research (MOHESR) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Coal Science & Technology (0253-2336) is the property of Coal Science & Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The stability of nanoparticles is a major challenge in thermal and electrocatalysis. This is especially true for core‐shell nanoparticles where only a few monolayers of noble metal protect the usually non‐noble core material. In this work, we utilize the practical nobility concept to engineer stable core‐shell nanoparticles with a self‐passivating core material. Specifically, tantalum carbide as core material in combination with a 1–3 monolayer thick platinum shell exhibits exceptional stability in aqueous media. The core‐shell catalyst shows no sign of structural changes after 10,000 degradation cycles up to 1.0 VRHE. Due to the efficient passivation of tantalum carbide at the solid/liquid interface, the dissolution reduces by a factor of eight compared to bare Pt. Our findings confirm that passivating core materials are highly beneficial for the stabilization of core‐shell nanomaterials in aqueous media. They open up new ways for the rational design of cost‐efficient but stable non‐noble core – platinum shell nanoparticles where harsh, oxidizing conditions are employed. [ABSTRACT FROM AUTHOR]

Copyright of China Mechanical Engineering is the property of Editorial Board of China Mechanical Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Stretchable electronic devices as an emerging electronic application product break the limitations of traditional planar rigid circuits and further expand the application fields of optoelectronics. Stretchable organic field-effect transistors (STOFETs) are an indispensable class of stretchable electronic devices, especially in wearable electronics, implantable electronics and skin like electronics. Therefore, extensive research effort has been devoted to the development of high-performance STOFETs, and remarkable advances in materials, processing techniques and applications have been achieved. Here, the latest studies of core materials for STOFETs are reviewed, mainly focusing on electrodes, dielectric layers and semiconductor layers. Then, the recent progress of some approaches for fabricating intrinsic STOFETs is mentioned, including solution methods, printing, and other methods. Detailed descriptions of the various stretchable electronic device applications of STOFETs are provided, along with their electrical/mechanical properties and examples of device applications. To conclude, a brief future outlook is presented. [ABSTRACT FROM AUTHOR]

Using nanoencapsulated phase change materials (NanoPCMs) for thermal energy storage has great application prospects in addressing the mismatch issues between energy supply and demand. However, the rapid, large-scale preparation of NanoPCMs is a challenge. Here, we developed a facile, efficient, green, and continuous method for the ultrafast preparation of NanoPCMs for energy storage using microwave-assisted polymerization with cross-linked poly(methyl methacrylate) and the PCM n-octadecane utilized as the shell and core materials, respectively. Sodium chloride (NaCl) acted as a microwave sensitizer and synergized with emulsifier to control the particle size of the NanoPCMs. Through orthogonal experiments, we investigated the effects of microwave power, temperature, and polymerization time on the properties of the NanoPCMs. The optimum conditions were 1.0 wt% NaCl, 60 °C, 10 min, and 600 W. The resulting NanoPCMs with uniform, spherical, core–shell structures were successfully utilized as thermal energy storage materials. The encapsulation efficiency was 50.8% and the NanoPCMs exhibited a particle size of ca. 95 nm, a high latent heat storage capacity of ca. 114.9 J g−1, and good thermal stability. In particular, the reaction time was greatly reduced from 12 h to 10 min, 100 times faster than conventional hydrothermal polymerization. Based on these parameters, the continuous, efficient production of microwave-assisted NanoPCMs was realized through reactor design, laying a foundation for the commercial production of NanoPCMs. [ABSTRACT FROM AUTHOR]

Reducing losses in electrical devices is essential for reducing global energy consumption. Losses in the core of electrical machines constitute a significant part of the overall losses—their share increases with the number of machines powered by PWM converters, especially for high-speed machines. Limiting core losses requires precise determination at the design stage of the device. Achieving this goal is possible thanks to numerical or analytical simulation. A necessary input for this process is the correct determination of the properties of the core material. The sheet loss, however, changes due to the machining process, primarily punching. The subject of the work is to develop a sufficiently accurate approximation of electrical steel sheet-specific loss, taking into account the effects of cutting and the width of a given machine element for a wide range of induction and frequency. The method also enables the extrapolation of losses for higher frequencies relevant from the point of view of generating losses in the machine. The developed loss approximation can be used in the finite element simulation and in applying analytical methods. The technique can be successfully used for many grades of non-oriented sheet metal, provided that the requirements specified in the work are met. The proposed approximation allows us to determine the loss of a sample of a certain width in a wide range of magnetic induction magnitude and frequency with an accuracy not worse than 4%. [ABSTRACT FROM AUTHOR]

A class of adamantane‐like molecular materials attracts attention because they exhibit an extreme non‐linear optical response and emit a broad white‐light spectrum after illumination with a continuous‐wave infrared laser source. According to recent studies, not only the nature of the cluster molecules, but also the macroscopic structure of the materials determines their non‐linear optical properties. Here we present a systematic study of cluster dimers of the compounds AdR4 and [(RT)4S6] (T = Si, Ge, Sn) with R = methyl, phenyl or 1‐naphthyl to gain fundamental knowledge about the interactions in the materials. For all compounds, a similar type of dimer structures with a staggered arrangement of substituents was determined as the energetically most favorable configuration. The binding energy between the dimers, determined by including London dispersion interactions, increases with the size of the core and the substituents. The cluster interactions can be classified as substituent‐substituent‐dominated (small cores, large substituents) or core–core‐dominated (large cores, small substituents). Among various possible dimer conformers, those with small core–core distances are energetically preferred. Trimer and tetramer clusters display similar trends regarding the minimal core–core distances and binding energies. The much lower energy barrier determined for the rotation of substituents as compared to the rotation of the cluster dimers past each other indicates that the rotation of substituents more easily leads to different conformers in the material. Thus, understanding the interaction of the cluster dimers allows an initial assessment of the interactions in the materials. [ABSTRACT FROM AUTHOR]

The processes that control irradiation creep are dependent on the temperature and the rate of production of freely migrating point defects, affecting both the microstructure and the mechanisms of mass transport. Because of the experimental difficulties in studying irradiation creep, many different hypothetical models have been developed that either favour a dislocation slip or a mass transport mechanism. Irradiation creep mechanisms and models that are dependent on the microstructure, which are either fully or partially mechanistic in nature, are described and discussed in terms of their ability to account for the in-reactor creep behaviour of various nuclear reactor core materials. A rate theory model for creep of Zr-2.5Nb pressure tubing in CANDU reactors incorporating the as-fabricated microstructure has been developed that gives good agreement with measurements for tubes manufactured by different fabrication routes having very different microstructures. One can therefore conclude that for Zr-alloys at temperatures < 300 °C and stresses < 150 MPa, diffusional mass transport is the dominant creep mechanism. The most important microstructural parameter controlling irradiation creep for these conditions is the grain structure. Austenitic alloys follow similar microstructural dependencies as Zr-alloys, but up to higher temperature and stress ranges. The exception is that dislocation slip is dominant in austenitic alloys at temperatures < 100 °C because there are few barriers to dislocation slip at these low temperatures, which is linked to the enhanced recombination of irradiation-induced point defects. [ABSTRACT FROM AUTHOR]

A liquid crystal (LC) mixture in liquid crystal on silicon (LCoS) is the core material for augmented reality (AR) displays. However, a LC mixture with high birefringence (Δn) and large dielectric anisotropy (Δε) possesses high viscosity (γ1), which results in a slow response time of LCoS devices for AR displays. This work proposes to apply difluorovinyl-based LC diluters to fine balance the low viscosity, high ∆n, and large ∆ε of the LC mixture for a fast response time. Through studying their effects on the key electro-optical properties of a high-∆n LC mixture, it is found that doping these diluter molecules to a high-∆n LC mixture can decrease the viscoelastic coefficient (γ1/K11), increase ∆ε and the figure of merit, maintain a wide nematic phase temperature range, a high clearing point, and ∆n. It also means that these diluters could effectively regulate the relationship between ∆n, ∆ε, and γ1 in the LC mixtures to achieve a fine balance of various excellent properties and further improve the LC device's response time. The widespread applications of these liquid crystal diluters in emerging liquid crystal optical devices are foreseeable. [ABSTRACT FROM AUTHOR]

This research work uses sp3d5s* tight-binding models to design and analyze the structural properties of group IV and III-V oriented, rectangular Silicon (Si) and Gallium Arsenide (GaAs) Nanowires (NWs). The electrical characteristics of the NWs, which are shielded with Lanthanum Oxide (La2O3) material and the orientation with z [001] using the Non-Equilibrium Green Function (NEGF) method, have been analyzed. The electrical characteristics and the parameters for the multi-gate nanowires have been realized. A nanowire comprises a heavily doped n+ donor source and drains doping and n-donor doping at the channel. The specified nanowire has a gate length and channel length of 15 nm each, a source-drain device length LSD = 35 nm, with La2O3 as 1 nm (gate dielectric oxide) each on the top and bottom of the core material (Si/GaAs). The Gate-All-Around (GAA) Si NW is superior with a high (ION/IOFF ratio) of 1.06 × 109, and a low leakage current, or OFF current (IOFF), of 3.84 × 10−14 A. The measured values of the mid-channel conduction band energy (Ec) and charge carrier density (ρ) at VG = VD = 0.5 V are −0.309 eV and 6.24 × 1023 C/cm3, respectively. The nanowires with hydrostatic strain have been determined by electrostatic integrity and increased mobility, making them a leading solution for upcoming technological nodes. The transverse dimensions of the rectangular nanowires with similar energy levels are realized and comparisons between Si and GaAs NWs have been performed. [ABSTRACT FROM AUTHOR]

Cellulose is classified as one of the most abundant biopolymers in nature. Its excellent properties have gained a lot of interest as an alternative material for synthetic polymers. Nowadays, cellulose can be processed into numerous derivative products, such as microcrystalline cellulose (MCC) and nanocrystalline cellulose (NCC). MCC and NCC have demonstrated outstanding mechanical properties owing to their high degree of crystallinity. One of the promising applications of MCC and NCC is high-performance paper. It can be utilized as a substitute for the aramid paper that has been commercially used as a honeycomb core material for sandwich-structured composites. In this study, MCC and NCC were prepared by extracting cellulose from the Cladophora algae resource. MCC and NCC possessed different characteristics because of their distinct morphologies. Furthermore, MCC and NCC were formed into a paper at various grammages and then impregnated with epoxy resin. The effect of paper grammage and epoxy resin impregnation on the mechanical properties of both materials was studied. Then, MCC and NCC paper was prepared as a raw material for honeycomb core applications. The results showed that epoxy-impregnated MCC paper outperformed epoxy-impregnated NCC paper with a compression strength of 0.72 MPa. The interesting result from this study is that the compression strength of the MCC-based honeycomb core was comparable to the commercial ones despite being made of a natural resource, which is sustainable and renewable. Therefore, cellulose-based paper is promising to be used for honeycomb core applications in sandwich-structured composites. [ABSTRACT FROM AUTHOR]

[Display omitted] • The loading content of SA in the PUF microcapsules was approximately 40%. • The antibacterial rates of SA@PUF after 35 days against S. aureus and P. aeruginosa remained at 80 % and 81 %, increased by 60 % and 62 % compared with pure SA, respectively. • The long-term antibacterial mechanisms were the toxicity of SA and the continuous generation of ROS. • The SA@PUF coating exhibited the excellent anti-corrosion property with |Z| 0.01Hz of 5.51 GΩ cm2. • The SA@PUF coating was effective in an actual marine environment. This work successfully synthesized the salicylic acid@polyurea-formaldehyde (SA@PUF) microcapsules with PUF microcapsules as shell material and SA as core material. The loading content of SA in the PUF microcapsules was approximately 40 %. The SA@PUF microcapsules had excellent long-term antibacterial properties because the PUF microcapsules controlled the release of SA antifouling agents with the ability to induce reactive oxygen species generation and inactivate bacteria. The antibacterial efficiency of SA@PUF microcapsules after 35 days against Staphylococcus aureus and Pseudomonas aeruginosa remained at 80 % and 81 %, increased by 60 % and 62 % compared with pure SA, respectively. The impedance modulus at 0.01 Hz of the SA@PUF coating reached 5.51 GΩ cm2, much higher than blank coating (2.55 GΩ cm2) and PUF coating (4.94 GΩ cm2), indicating that the anti-corrosion property of the SA@PUF coating was much better. This work would contribute to developing novel coatings with long-term antibacterial activity and excellent anti-corrosion performance. [ABSTRACT FROM AUTHOR]

Kinetic analysis remains a powerful tool for studying a large variety of reactions, which lies at the core of material science and industry. It aims at obtaining the kinetic parameters and model that best describe a given process and using that information to make reliable predictions in a wide range of conditions. Nonetheless, kinetic analysis often relies on mathematical models derived assuming ideal conditions that are not necessarily met in real processes. The existence of nonideal conditions causes large modifications to the functional form of kinetic models. Therefore, in many cases, experimental data hardly obey any of these ideal models. In this work, we present a novel method for the analysis of integral data obtained under isothermal conditions without any type of assumption about the kinetic model. The method is valid both for processes that follow and for those that do not follow ideal kinetic models. It consists of using a general kinetic equation to find the functional form of the kinetic model via numerical integration and optimization. The procedure has been tested both with simulated data affected by nonuniform particle size and experimental data corresponding to the pyrolysis of ethylene-propylene-diene. [ABSTRACT FROM AUTHOR]

Despite the politically oppressive period of Normalization that followed the Prague Spring in the late 1960s and 1970s in Czechoslovakia, performance artists had to find a way of creating despite the heavy policing of cultural spaces. Křižovnická škola čistého humoru bez vtipu (Crusaders School of Pure Humour with No Jokes) found their creative sanctuary by making works in the semi-public spaces of pubs. The group of artists, performers, poets, philosophers, and photographers conceptualised of their meetings in pubs as a form of artistic practice. Their core materials became meeting, community, alcohol, and the pub atmosphere which they utilized to create often impromptu and satirical performance works. Their works such as Fando, nezlob se (Don't Be Angry, Fando, 1969), which was an alcoholic version of ludo that the group regularly played, or Křižovnický kalendář (Crusader Calendar, 1972), in which the group met on the last Friday of every month to meet and capture themselves on camera, used meeting in the pub and drinking as both the site and the material for their performances. The group conceived of their meetings in the pub through phenomenology - drinking together in a pub functioned as an experiential epistemology for the group. The-pub became a stand-in for Heideggerian Da-sein and being-in-the-world was replaced by being-in-the-pub. This formulation anticipates pub as a prerequisite and a method for exploration of meeting. Their pub meetings were for them a free arena of artistic expression that relied on communal artmaking. As opposed to "the meeting" that defined the official sphere, Crusaders' pub "meetings" were of the people – chaotic, loud, disorderly, and fuelled by alcohol. Crusaders' shared practice illustrates how meeting can be a potent political and artistic tool to create and exercise freedom under political oppression. [ABSTRACT FROM AUTHOR]

Early childhood caries (ECC) involve extensive coronal tooth structure loss, and tooth reconstruction remains highly challenging. To fulfill preclinical assessment, the present study investigated the biomechanics of non-restorable crownless primary molars that were restored by stainless steel crowns (SSC) using different composite core build-up materials. Computer-aided design-integrated 3D finite element and modified Goodman fatigue analyses were performed to determine stress distribution, risk of failure, fatigue life and dentine–material interfacial strength for the restored crownless primary molars. A dual-cured resin composite (MultiCore Flow), a light-cured bulk-fill resin composite (Filtek Bulk Fill posterior), a resin-modified glass-ionomer cement (Fuji II LC) and a nano-filled resin-modified glass-ionomer cement (NRMGIC; Ketac N100) were used as core build-up composite materials in the simulated models. The finite element analysis showed that types of core build-up materials affected the maximum von Mises stress only in the core materials (p-value = 0.0339). NRMGIC demonstrated the lowest von Mises stresses and revealed the highest minimum safety factor. The weakest sites were along the central grooves regardless of type of material, and the ratio of shear bond strength to maximum shear stress at the core–dentine interface of the NRMGIC group was lowest among the tested composite cores. However, all groups provided lifetime longevity from the fatigue analysis. In conclusion, core build-up materials differentially influenced the von Mises stress (magnitude and distribution) and the safety factor in crownless primary molars restored with core-supported SSC. However, all materials and the remaining dentine of crownless primary molars provided lifetime longevity. The reconstruction by core-supported SSC, as an alternative to tooth extraction, may successfully restore non-restorable crownless primary molars without unfavorable failures throughout their lifespan. Further clinical studies are required to evaluate the clinical performance and suitability of this proposed method. [ABSTRACT FROM AUTHOR]

This article reviews all available information on the species composition, current distribution, and origins of the neobiotic (non-indigenous and restoring the lost range) freshwater mollusks in Siberia. An extensive literary search has been carried out, and virtually all existing publications of recent decades on the findings of freshwater mollusk species new to Siberia were taken into account. We examined extensive malacological collections of some of Russia's and Kazakhstan's scientific organizations. The core of the examined material is our own observations and collections made in various parts of Siberia and adjacent areas. An annotated checklist of neobiotic species of mollusks reliably recorded in Siberia is presented, and probable mechanisms and "corridors" of infiltration of these species into the region are discussed. Most of the discovered snail species belong to a group popular among aquarists, and their source of introduction is obvious. Another large portion of species infiltrate into the region with the development of fish farming. A classification of species of neobiotic freshwater mollusks of Siberia was proposed and a forecast was made for changes in the Siberian freshwater malacofauna for the coming decades. In our opinion, at present it is possible to accept the newest stage in the genesis of the freshwater malacofauna of Siberia, occurring in conditions specific to the Anthropocene. [ABSTRACT FROM AUTHOR]

The mechanical consequences of core disruptive accidents (CDAs) are a major safety concern in sodium-cooled fast reactors. Once core disruption occurs, liquefied core materials rapidly disperse vertically and radially. The dispersed materials penetrate the pin bundles and control rod guide tubes (CRGTs) before freezing at the edge of the penetration zone as heat is transferred to surrounding structures. Such freezing phenomena can suppress the negative reactivity feedback of fuel dispersion. The discharge of core materials can be impeded, resulting in a molten core pool formation when tight blockages occur inside CRGTs due to frozen material. Accordingly, freezing phenomena of core materials play a key role in governing the mechanical consequences of a CDA. To validate a freezing model implemented in our CDA analysis code, ASTERIA-SFR, a preliminary simulation of the THEFIS RUN#1 test, was performed. The calculation results show that freezing on the structural wall and crust formation were key phenomena affecting the penetration behavior, and the structural heat transfer is an important parameter. A remarkable reduction of the heat transfer coefficient was required to reproduce the penetration length observed in the experiment. This suggests that the momentum exchange and flow regime at the leading edge as well as heat transfer should be well modeled to predict the freezing phenomena in rapidly evolving CDAs. [ABSTRACT FROM AUTHOR]

The leakage inductance of an integrated transformer is usually utilized as the series inductor of an LLC topology. However, leakage inductance exists on both primary and secondary sides of an integrated transformer and secondary leakage inductance leads the control and design of the converter to difficulty. In this article, a novel topology forinserted-shunt integrated transformers is proposed that has low secondary leakage inductance. The inserted shunt of the proposed topology is not segmental and can be located conveniently within the transformer. In addition, the inserted shunt does not require low permeability core material, simplifying its manufacture. The design and modeling of the proposed transformer topology are presented and verified by finite-element analysis and experimental implementation. The proposed topology is also compared with a recently published inserted-segmental-shunt integrated transformer. It is shown that the proposed transformer provides higher efficiency and lower ac resistance. Finally, an LLC resonant converter is implemented to examine the performance of the proposed integrated transformer in practice. [ABSTRACT FROM AUTHOR]

Electrical equipment operates under various temperatures and non-sinusoidal excitation, which makes magnetic properties of soft magnetic materials quite different from those under room temperature and sinusoidal excitation. Magnetic properties and loss characteristics of the ferrite (N87) and nanocrystalline alloy (FT-3KL) are measured and analyzed in the range of 25 °C to 125 °C from 5 kHz to 20 kHz under both square and rectangular excitation with different duty ratios. The temperature dependence of these materials under different conditions is systematically compared with normalization method. The comprehensive performance of core materials is discussed in combination with the experimental phenomena and results. [ABSTRACT FROM AUTHOR]

Wheat (triticum aestivum l.) breeding technology can face a great challenge on the long cycle, low efficiency, and narrow genetic background. An important breakthrough can be combining the high-throughput phenotyping of in-field wheat and genome-wide association, thereby revealing the genetic variation in dynamic response to environmental stress. Fortunately, the unmanned aerial vehicle (UAV) remote sensing and machine learning can be expected to bridge the genotype–phenotype gap of the wheat in the breeding process. Among them, frost tolerance is an important phenotype target, particularly with the winter survival of wheat in various environments. It is a high demand for the rapid and cost-effective assessment of frost tolerance from the UAV multi-spectral imagery using machine learning. In this study, a genome-wide association study (GWAS) was assessed for the quantitative genomic analysis of wheat frost tolerance. A bi-parental wheat population consisting of 491 doubled haploid lines was also used in four study sites. 491 wheat core materials with a relatively consistent growth stage were selected to obtain their high-density genotype data with the 660 kb single nucleotide polymorphism (SNP). The UAV-based multi-spectral imagery of the wheat canopy was collected at the overwintering stage at four experimental sites. At the same time, the wheat in-field phenotypes of frost tolerance were investigated by the wheat breeding experts at the same time. The image pre-processing was performed on the features generation of 16 spectral vegetation indices, including image mosaic, geometric correction, radiometric correction and index calculation. Image segmentation was utilized to obtain the features of the wheat canopy using unsupervised clustering. The features correlation analysis and importance analysis were implemented to compare with the in-field investigation, in order to identify quantitative trait loci (QTL) underlying frost tolerance. A comparison was then made on the evaluation models of wheat freezing injury established by random forests (RF), extreme gradient boosting (XGBoost), gradient boosting decision tree (GBDT), and support vector machine (SVM). The results showed that significantly high accuracy was achieved up to 67.94% of the classifier in the XGBoost, compared with the in-field investigation. The correlation and importance of features were also analyzed during this time. The importance of 22 spectral features to the prediction performance of the classifier was evaluated using the information gain brought by the feature, when the sub node of the classifier split. The results showed that there was the most important for the prediction performance of the classifier in the simplified Canopy Chlorophyll content index (SCCCI) among the 16 spectral features of the wheat canopy. Three QTLs were also closely related to the frost resistance detected by the genome-wide association analysis. The three loci of 2B, 3A, and 5A on chromosome 21 of wheat presented a significant SNP, even exceeding the threshold (-lgP=4). The SNPs were continuously distributed. Therefore, the spectral features using UAV remote sensing can be expected to serve as the wheat frost resistance QTL. The UAV-enabled phenotyping can be an effective, high-throughput, and cost-effective approach to understanding the genetic basis of wheat frost tolerance in genetic studies and practical breeding. This finding can also provide a fast way for the high-throughput phenotyping of wheat frost tolerance for wheat winter survival in the field. [ABSTRACT FROM AUTHOR]

Microencapsulation of various substances encompasses a vast field of exceptional application in modern medicine, pharmacy, perfumery and cosmetics, biomedical engineering, as well as in the textile, petroleum and general industries. Although this process can be effected in different ways, depending on its nature (physical, chemical or physicochemical process), physicochemical group of procedures and in particular coacervation is one of the most preferred in terms of ecological purity and biodegradability of the materials used in this method of producing microcapsules. The material in coacervation process used to produce the microcapsules is entirely from natural sources, which would allow their biodegradability over time. The coacervation can be divided into two types: simple and complex. In the microencapsulation of expensive natural products, they need to be diluted with a suitable solvent for three reasons: on the one hand - due to the cost of the encapsulated substance, on the second - to stabilize the core material, and on the third hand - to increase the efficiency of the process, resulting in higher yield and quality of the microcapsules obtained. This article examines the effect of the type of solvent (playing the role of media for diluting the encapsulated substance) on the encapsulation efficiency, yield, and quality of the microcapsules obtained, in the microencapsulation of rose oil using the complex coacervation process. [ABSTRACT FROM AUTHOR]

Composite sandwich structures are well-suited for applications requiring high bending strength, flexural rigidity, crashworthiness, and light weight. However, skin--core debonding and core failure remain a barrier to optimal structural performance when polymeric foams are used as core materials. Suppressing or compartmentalising these failure modes can enhance the structural integrity of sandwich structures. In this paper, the flexural response of a sandwich structure was improved by adding carbon fibre-reinforced plastic in the form of through-thickness ribs during the manufacturing process. The effect of the position of the ribs was investigated using a quasistatic three-point bend test. A camera was used to capture failure events, while the digital image correlation technique provided the full-strain field at different stages of loading. Improved flexural performance was obtained when a reinforcement was placed on either side of the loading roller. With this configuration, skin--core debonding was restricted to a confined portion of the panel, resulting in a more localised and stable fracture process, which involved enhanced foam crushing and hardening. A simple FEA approach has been adopted in this paper and has proven to be an effective approach for capturing the details of the failure process, including the debonding in the composite foam structures, without the need for complex and computationally expensive interface modelling. [ABSTRACT FROM AUTHOR]

The aim of this study is to analyze the properties of Paulownia tomentosa x elongata plantation wood from Serbia, considering the influence of the stem height (0 to 1 m and 4.5 to 6 m above soil level—height spot) and radial position from the pith to bark (in the core, near the bark, and in between these zones—cross-section spot). The results show that most properties are improved when the samples were taken from upper parts of the tree (height spot) and from the near bark spot (cross-section spot). The mean density measured 275 kg/m3 at the stem height between 4.5–6 m and 245 kg/m3 for the samples collected from 0–1 m trunk height. The density had the highest value on the spot near bark (290 kg/m3), for the mature wood at a height of 4.5–6 m, and near pith had a mean density of 230 kg/m3. The Brinell hardness exhibited highest values in the axial direction (23 N/mm2) and near bark (28 N/mm2). The bending strength was 41 N/mm2 for the trunk's height range of 4.5–6 m and 45 N/mm2 in the cross-section, close to cambium. The three-point modulus of elasticity (MOR) of the samples taken at a stem height of 4.5 to 6 m was up to 5000 N/mm2, and on the spot near bark, the MOR measured 5250 N/mm2. Regarding compressive strength, in the cross-section, near the pith, the mean value was the highest with 23 N/mm2 (4.5–6 m), whilst it was 19 N/mm2 near bark. The tensile strength was, on average, 40 N/mm2 for both 0–1 m and 4.5–6 m trunk height levels and 49 N/mm2 between bark and pith. The screw withdrawal resistance measured 58 N/mm for the samples extracted at a stem height of 4.5 to 6 m and 92 N/mm for the specimens collected near pith. This study stresses the influence, in short-rotation Paulownia timber, of indicators, such as juvenile and mature wood (difference emphasized after the fifth year of growth) and height variation, on the physical and mechanical properties of sawn wood. This study will help utilize more efficient sustainable resources, such as Paulownia plantation wood. This fast-growing hardwood species from Europe is adequate as a core material in sandwich applications for furniture, transport, sport articles, and lightweight composites, being considered the European Balsa. [ABSTRACT FROM AUTHOR]