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Recently, replacing plastic packaging materials with biobased alternatives has been trending in the field of food packaging. The role of food packaging materials is to contain and protect the product throughout the supply chain, and the most used materials for this are polyolefins due to their functionality and affordability. However, environmental awareness and the new regulations and restrictions have been strong drivers to push the development towards biobased materials. In this study, the feasibility and potential of biowaxes used as a dispersion barrier coating formulation material were examined. Four commercial biowaxes were selected for the study, and their nano‐ and crystalline structures were determined by wide‐angle X‐ray scattering (WAXS). The biowaxes were melted and dispersed into a stable water‐based dispersion. Barrier coating formulations were prepared using two different polymer dispersions mixed with the waxes and additives. A fibre substrate was coated with the prepared formulations, and their barrier properties were studied. The properties of biowax‐containing coatings showed similar or minor improvements compared to the reference. However, foldability was especially improved in the biowax sample. Interestingly, this sample contained wax, which was structurally most stable, presenting an orthorhombic phase in all studied states. Based on our results, introducing biowax materials is a viable solution to replace part of the formulation materials and adjust the barrier performance of existing dispersion polymers. Our results also suggest that the nanostructure of waxes might play a role in an optimal solution. However, all these observations deserve more studies, and the share of biowax in barrier coatings will need further optimisation in the future. [ABSTRACT FROM AUTHOR]

Recycling high-density micronized (HDM) heat-press glass ceramic ingots to press several restorations would be economical and reduce waste. However, to achieve this, the effects of re-pressing on the optical properties and long-term durability of HDM glass ceramics must be completely understood. The aim of this study was to assess the effects of re-pressing and glazing on the optical properties of HDM heat-press glass ceramic. Twenty-one HDM glass ceramic (Initial LiSi Press) discs were prepared and randomly divided into three groups (n = 7 per group): single heat pressing, double heat pressing, and triple heat pressing. Optical properties, surface roughness, and crystalline structure were measured for each group at three time points: before glazing and thermocycling, after glazing, and after thermocycling. The effect of these independent variables on optical properties were assessed by two-way ANOVA, and Tukey's post hoc test assessed the differences between groups. Heat re-pressing HDM glass ceramic significantly altered its color, reduced translucency, and reduced surface roughness (P < 0.001). After the second heat-press, the color (ΔΕ 00) and translucency parameter changes (ΔTP 00) exceeded perceptible thresholds but not clinically acceptable thresholds, but these were exceeded after the third press for ΔΕ 00. Additionally, glazing lightened the shade of the ceramic, reduced translucency, and reduced surface roughness (P < 0.001), with ΔΕ 00 and ΔTP 00 changes exceeding the perceptible but not the clinically acceptable threshold. Thermocycling produced ΔTP 00 changes that exceeded the clinically acceptable threshold. Further studies of the effects of heat re-pressing on HDM glass ceramic are now needed to progress toward clinical translation. [ABSTRACT FROM AUTHOR]

Highlights This study aims at the assessment of damage on crystallinity of fiber reinforced thermoplastic (FRTP) composites resulting from mechanical polishing to demonstrate a novel methodology enabling comprehensive crystalline structural characterization. Investigating the crystalline structure is relevant for understanding the relationship with the mechanical properties. In a previous study, FRTPs have successfully been processed to the thickness of 5 μm or below via an innovative polishing strategy, which for the first time visualized the crystalline morphologies by polarized optical microscopy. Analyzing these sections via micro‐Raman and micro‐infrared spectroscopies facilitate the quantification of these structure. However, no study reports on the correct interpretation of FRTP data appropriately considering the damage resulting from mechanical polishing to date. Herein, we report fundamental knowledge on this aspect via detailed Raman micro‐spectroscopic investigations to demonstrate our novel strategy. Four types of FRTPs with major matrix resins (GF/PBT, CF/PA6, CF/PEEK and GF/PP) were analyzed and the damage on both polished cross‐sections, prepared by traditional process, and the thin sections was confirmed to be approx. 1%–2% crystallinity, which solidified the credibility of the obtained analytical data. Then, the newly established methodology of ‘cross‐referenceable microscopic and micro‐spectroscopic analyses for FRTPs’ was applied for comprehensive crystalline structural characterization. Cross‐sectioning and thin‐sectioning of FRTPs. Evidencing of damage on the crystallinity resulting from mechanical polishing. Equations to convert Raman spectral data into crystallinity. Strategy for considering the anisotropy of Raman measurements. Practical application of novel microscopic and micro‐spectroscopic strategies. [ABSTRACT FROM AUTHOR]

When it comes to sustainable and efficient energy solutions, organic semiconductors can play an important role in thermoelectric applications, since they are non‐toxic, cheap, made of abundant chemical species, and show intrinsically low thermal conductivities. Their electrical conductivity can be optimized via doping. Yet, thermal conduction should be as low as possible and, to this end, the atomic scale mechanisms behind heat transport –e.g. the correlation between morphology and thermal conductivity or the role of doping– should be understood in detail. Fully atomistic molecular dynamics calculations of the lattice thermal conductivity of doped poly(3,4‐ethylenedioxythiophene) (PEDOT) highly ordered, quasi‐crystalline nanofibers are presented here. It is found that the conductivity along the backbone direction is not necessarily the highest, but it depends on the length of the PEDOT chains, thus the degree of anisotropy depends on the the aspect ratio of the nanofiber. Indeed, transport along the lamellar direction can be of the same order or higher than that of the backbone if their lengths are comparable. These results challenge the usual expectation that thermal conduction along the backbone largely exceeds those along the lamellar and π − π direction and have the important consequence that the anisotropy could be leveraged in thermal management applications. [ABSTRACT FROM AUTHOR]

In ternary nitrides, the Ga0.9Fe3.1N sample has ultimately been prepared through solid‐gas preparation for the gallium‐richest phase GaFe3N. The substitution of gallium atoms for iron atoms weakens the saturation magnetization of ferromagnetic γʹ‐Fe4N and induces the transmission from ferromagnetism to antiferromagnetism. A new magnetic behavior, defined as the spin glassy magnetic state, has been observed in the temperature‐dependent magnetic performance measurement process for Ga0.9Fe3.1N. The magnetic competition between ferromagnetic and antiferromagnetic Fe–Fe bonds will lead to the spin frustration of the magnetic system. And even the positional disorders caused by substitution, will all be responsible for the spin glassy behavior in Ga0.9Fe3.1N. [ABSTRACT FROM AUTHOR]

Plasmonic nanocavities are receving increased attention from the nanophotonics, nanoelectronics, and quantum optics community due to their ability to confine light in extremely small volumes. Coupling colloidal plasmonic nanocrystals to metal films is an inexpensive approach to fabricate virtually unlimited individual resonators that can be tuned by adjusting nanoparticle size, gap thickness, and refractive index. The focus is on silver nanocubes separated from a gold mirror by thin amorphous dielectric layers (Al2O3, TiO2). The optical response is measured and correlative electron microscopy is performed on a large number (>800) of individual resonators to unveil the statistical distribution of gap plasmon modes and assess systematically their sensitivity. A sensitivity as large as 8 nm/nm to nanocube size variation, 50 nm/nm to Al2O3 thickness variation, and 130 nm/RIU for index change of the spacer layer is found. With the help of numerical simulations, this approach enables to infer a quantitative statistical distribution of molecular coatings present on the nanocubes surface, such as polyvinylpyrrolidone, which can affect the performance of nanoelectronic devices and assess the strategy to remove it. Finally, polarization‐resolved measurements enable to unveil a birefringent behavior when nanocubes are supported on annealed TiO2 layers (2–4 nm). [ABSTRACT FROM AUTHOR]

In actual underground rock engineering, to prevent the deformation and damage of the rock mass, rock bolt reinforcement technology is commonly employed to maintain the stability of the surrounding rock. Therefore, studying the anchoring and crack-stopping effect of rock bolts on fractured granite rock mass is essential. It can provide significant reference and support for the design of underground engineering, engineering safety assessment, the theory of rock mechanics, and resource development. In this study, indoor experiments are combined with numerical simulations to explore the impact of fracture dip angles on the mechanical behavior of unanchored and anchored granite samples from both macroscopic and microscopic perspectives. It also investigates the evolution of the anchoring and crack-stopping effect of rock bolts on granite containing fractures with different dip angles. The results show that the load-displacement trends, displacement fields, and debris fields from indoor experiments and numerical simulations are highly similar. Additionally, it was discovered that, in comparison to the unanchored samples, the anchored samples with fractures at various angles all exhibited a higher degree of tensile failure rather than shear failure that propagates diagonally across the samples from the regions around the fracture tips. This finding verifies the effectiveness of the numerical model parameter calibration. At the same time, it was observed that the internal force chain value level in the anchored samples is higher than in the unanchored samples, indicating that the anchored samples possess greater load-bearing capacity. Furthermore, as the angle αs increases, the reinforcing and crack-stopping effects of the rock bolts become increasingly less pronounced. [ABSTRACT FROM AUTHOR]

In this study, we conduct a comparative analysis of single-beam laser annealing (SBLA) and dual-beam laser annealing (DBLA) techniques for semiconductor manufacturing. In the DBLA approach, two laser beams were precisely aligned to simultaneously heat a phosphorus-doped silicon (Si) wafer. The main objective was to investigate the impact of the two annealing techniques on the electrical properties, crystalline structure, and diffusion profile of the treated phosphorus-doped Si at equivalent laser powers. Both SBLA and DBLA improved the electrical properties of the phosphorus-doped Si, evidenced by increased carrier concentration and reduced carrier mobility. Additionally, the crystalline structure of the phosphorus-doped Si showed favorable modifications, with no defects and improved crystallinity. While both SBLA and DBLA produced similar phosphorus profiles with no significant redistribution of dopants compared to the as-implanted sample, DBLA achieved a higher activation ratio than SBLA. Although the results suggest improved dopant activation with minimal diffusion, further studies are needed to clearly confirm the effect of DBLA on dopant activation and diffusion. [ABSTRACT FROM AUTHOR]

The pdy-m-phenylene isophthalamide (PMIA) fiber is an organic high-performance fiber possessing excellent properties and versatile technical applications. It is widely used in protective clothing fields such as firefighter suits, flame-retardant suits, and racing suits, with great application value. However, due to the presence of abundant hydrogen bonds formed by amide groups along its macromolecular chains, the PMIA fiber has a compact and ordered structure. This compactness and extremely crystalline structure make it challenging for dye molecules to penetrate the PMIA fibers, rendering the dyeing process of PMIA fibers extremely difficult and time-consuming, severely limiting the applications of this kind of high-performance fiber in protective clothing and other fields. Therefore, improving the dyeability of PMIA fibers is crucial to unlock its full application potential and expand its application scope. To address the dyeing difficulties caused by the high hydrogen bonding density in the PMIA molecular structure, extensive research has focused on hydrogen bond regulation of PMIA fibers. Among these, the carrier dyeing method is currently the most commonly used approach for industrial production of dyed PMIA fibers. It utilizes small-molecule organic solvents to penetrate the fibers first, disrupting the hydrogen bond network and increasing the porosity, thereby accelerating dye absorption. However, many carriers used in this method suffer from issues such as irritating odors, high toxicity, and difficult recovery, limiting further applications of the carrier dyeing method. Moreover, research on the microscopic hydrogen bond regulation mechanism of PMIA fibers at the nanoscale is relatively lacking when using carriers, and the effects of carriers on different microscopic crystalline structures of PMIA fibers remain unexplored. Therefore, investigating the mechanism behind the dyeability differences of PMIA fibers with distinct crystalline states and improving their dyeability are of great significance for expanding the applications of PMIA fibers in the textile field. This study employs dimethyl sulfoxide (DMSO), a low-toxicity, low-cost solvent with mature recovery technology, as a hydrogen bond regulator. Molecular dynamics simulations and experiments are combined to study the effects of DMSO on the crystalline structure and dyeability of PMIA. Firstly, molecular models of PMIA and DMSO/PMIA with different crystalline states are constructed based on molecular dynamics simulation theory. The changes in hydrogen bond quantity and length, chain mobility (mean square displacement), and interfacial binding energy between PMIA and dye solution before and after DMSO treatment are calculated. Furthermore, SEM, FTIR, XRD characterisation of the PMIA fabrics are carried out and the apparent colour yield (K/S), dyeing rate and colour fastness are tested to mutually verify the simulation results. The computational results of the structural models demonstrate that DMSO can effectively disrupt the hydrogen bond network of PMIA, reducing the hydrogen bond quantity by 56.5% and 25.7% in the amorphous and crystalline regions, respectively, and significantly enhancing the chain mobility in the amorphous regions. Additionally, the interfacial binding energies between PMIA with different crystalline states and the dye molecules are higher after DMSO treatment, with a more substantial increase observed in the amorphous regions compared to the crystalline regions. Experimental results reveal that DMSO can effectively increase the surface roughness of PMIA fibers without significantly affecting their chemical structure and crystallinity. Meanwhile, the dyeability of PMIA is remarkably improved, with the K/S value and dye exhaustion increasing by 72.34% and 65.6%, respectively, and the wet rubbing fastness and light fastness enhancing by half a grade and one grade, respectively. The experimental results are consistent with the molecular dynamics simulation conclusions. This study provides a mechanistic guideline for selecting hydrogen bond regulators for PMIA fibers and offers new insights into improving the dyeability of PMIA fibers. [ABSTRACT FROM AUTHOR]

The physical modification of starch to produce resistant starch (RS) is a viable strategy for the glycemic index (GI) lowering of foods and functionality improvement in starchy food products. RS cannot be digested in the small intestine but can be fermented in the colon to produce short-chain fatty acids rather than being broken down by human digestive enzymes into glucose. This provides major health advantages, like better blood sugar regulation, weight control, and a lower chance of chronic illnesses. This article provides a concise review of the recent developments in physical starch modification techniques, including annealing, extrusion, high-pressure processing, radiation, and heat–moisture treatment. Specifically, the focus of this paper is on the alteration of the crystalline structure of starch caused by the heat–moisture treatment and annealing and its impact on the resistance of starch to enzymatic hydrolysis, as well as the granular structure and molecular arrangement of starch caused by extrusion and high-pressure processing, and the depolymerization and crosslinking that results from radiation. The impacts of these alterations on starch's textural qualities, stability, and shelf life are also examined. This review demonstrates how physically modified resistant starch can be used as a flexible food ingredient with both functional and health benefits. These methods are economically and ecologically sustainable since they successfully raise the RS content and improve its functional characteristics without the need for chemical reagents. The thorough analysis of these methods and how they affect the structural characteristics and health advantages of RS emphasizes the material's potential as an essential component in the creation of functional foods that satisfy contemporary dietary and health requirements. [ABSTRACT FROM AUTHOR]

In order to explore the changes in the performance of polyester fibers prepared by different processes under alkaline conditions, high tenacity (HT) polyester industrial fiber and fully drawn polyester yarn (FDY) of high speed spinning were selected for artificial accelerated aging tests in alkaline conditions at 85 °C. The mechanical properties of fibers were tested during the processes. Wide-angle X-ray diffraction, small-angle X-ray scattering and intrinsic viscosity were used to study the change in crystalline, lamellar structure and chemical structure of polyester fibers. The results showed that the changes in structure and properties of two polyester fibers in alkaline conditions can be divided into three stages. At the initial stage, the breaking strength and degree of orientation of the fibers first decreased significantly due to the effect of water and heat, while crystallinity remained constant. It was caused by the disorientation of amorphous orientated molecular chain segments in the frozen state, resulting in shrinkage. Then the decrease in breaking strength of fibers was slowed down, which was attributed to the breakage of amorphous molecular chains and the formation of a few new crystal structures. In the final stage of alkaline hydrolysis, the breaking strength of the fibers decreased significantly, while the crystallinity of fibers began to decline and the intrinsic viscosity reduced constantly, indicating that the breakage of amorphous molecular chain became the dominant factor. The alkaline hydrolysis reaction rate and the change degree of microstructure and mechanical property parameters of HT fibers were lower than those of FDY fibers, owing to the greater crystallinity and crystal size of HT fibers, which inhibited the erosion of water and OH-. As a result, HT fibers had a better alkaline hydrolysis resistance than FDY fibers. [ABSTRACT FROM AUTHOR]

Copyright of Food & Fermentation Industries is the property of Food & Fermentation Industries 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.)

Oleogel is a special gel system, regarded as an effective alternative to plastic fats in the food industry.Different gelation factors lead to different structural properties of oleogels due to their specific crystallization behavior.Here, the effects of four different esterification degrees of stearic acid including stearic acid(SA),glyceryl monostearate(GMS),glyceryl distearate(GDS),and glycerol tristearate(GTS) on the crystallization behavior in oleogels were investigated.The effects of esterification degree and concentrations of gelation factors on the crystallization behavior were explored by using rheology, X-ray diffraction,and polarized light microscope methods.The oleogels with SA, GMS, GDS and GTS exhibited solid-like behavior and formed strong gels.The oleogels with GMS has high oil-binding capacity.Thermodynamic performance results indicated that the oleogels with GMS exhibited superior thermal stability.They also were observed the most stable β-polymorphic structure and small needle-like crystals.FTIR spectroscopy revealed hydrogen bonding was observed in the oleogels with GMS, while it was not observed in the oleogels with SA, GDS, and GTS.Overall, the formation of hydrogen bonds between the two additional free hydroxyl end groups of GMS and the fatty acid carbonyl groups promoted the formation of a denser network structure in the oleogels with GMS, which can be effectively immobilized liquid oil.These findings provide strong theoretical support for the application of oleogels as substitutes for plastic fats. [ABSTRACT FROM AUTHOR]

Polyamide-6 (PA6), or nylon-6, is a widely used low-cost polymer material for various applications. Manufacturing PA6 into fibers involves a spinning process which orients the polymer chains into a semicrystalline structure. The most economical spinning process for PA6 fibers is melt extrusion. When stretching the produced fibers to high strains, the PA6 fibers transition the metastable γ phase back into the stable α phase. The effects of these large stretches on mechanical properties have not been explored after the stretch has been released. In this study, the effects on mechanical properties were studied by stretching the PA6 fibers from 10 to 50% tensile strain and subsequently releasing the fibers. The stretched fibers were characterized by X-ray diffraction and atomic force microscopy to determine the changes to the crystal structure and surface roughness. The stretched fibers were then tensile tested to failure and the tensile properties were examined. The stress-strain curves on the post-stretched PA6 fibers showed clear softening in the fibers with lower initial moduli after 30% stretching. These results may hold a clue to softening of fibers in applications with repeated loading and have implications for mechanical stability and fatigue of this polymeric material. [ABSTRACT FROM AUTHOR]

The molecular structure of a crystalline monolayer of hydrocarbon chains was modeled and studied via computer simulation using the Metropolis Monte Carlo algorithm at a temperature T = 300 K. The only interactions in this system occur through Lennard‐Jones dispersion forces and short‐range atom‐atom repulsion. The intent was to establish whether the chains were either rigidly extended or twisted via the thermal formation of gauche bonds and apply the results to understand observations made on two possible oleogelators: triacontane and stearic acid. Specifically, we aimed to understand if their observed crystalline monolayer thicknesses are due to gauche‐bond‐shortened hydrocarbon chains oriented perpendicular to the monolayer surface, or to fully extended rigid chains oriented at a tilt angle with respect to the surface. The results showed that crystals of hydrocarbon chains did not include significant gauche bonds, so that all molecules were rigidly extended, thus explaining the experimental data previously reported. Accordingly, TC and SA dimer molecules are packed in crystalline multilayers with tilt angles in relation to the methyl group plane. [ABSTRACT FROM AUTHOR]

1,3-bis((1H-1,2,4-triazol-1-yl)methyl)hexahydropyrimidine was readily prepared by cyclocondensation of propane-1,3-diamine with a mixture of (1H-1,2,4-triazol-1-yl)methanol and formaldehyde. The 1H- and 13C-NMR spectroscopic data of this ligand have been fully assigned and are consistent with the molecular structure. The crystalline structure of the compound was fully determined by single crystal X-ray diffraction at 150 K and at room temperature, together with the isobaric thermal expansion. Finally, during the first heating, DSC measurements showed no phase transition up to the melting temperature at 385.1 K (111.9 °C). [ABSTRACT FROM AUTHOR]

Copyright of China Synthetic Fiber Industry is the property of Sinopec Baling Petrochemical Company 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.)

Abstract When it comes to sustainable and efficient energy solutions, organic semiconductors can play an important role in thermoelectric applications, since they are non‐toxic, cheap, made of abundant chemical species, and show intrinsically low thermal conductivities. Their electrical conductivity can be optimized via doping. Yet, thermal conduction should be as low as possible and, to this end, the atomic scale mechanisms behind heat transport –e.g. the correlation between morphology and thermal conductivity or the role of doping– should be understood in detail. Fully atomistic molecular dynamics calculations of the lattice thermal conductivity of doped poly(3,4‐ethylenedioxythiophene) (PEDOT) highly ordered, quasi‐crystalline nanofibers are presented here. It is found that the conductivity along the backbone direction is not necessarily the highest, but it depends on the length of the PEDOT chains, thus the degree of anisotropy depends on the the aspect ratio of the nanofiber. Indeed, transport along the lamellar direction can be of the same order or higher than that of the backbone if their lengths are comparable. These results challenge the usual expectation that thermal conduction along the backbone largely exceeds those along the lamellar and π − π direction and have the important consequence that the anisotropy could be leveraged in thermal management applications.

As a new physical modification method, high-pressure treatment has been widely used in the processing of starch. In this paper, the effects of high-pressure treatment on the crystalline structure, gelatinization, retrogradation, digestion, thermal and rheological properties of starches are systematically summarized. High-pressure treatment can significantly decrease the relative crystallinities of starches and transform the A-type or C-type crystalline structure of starch into a B-type crystalline structure. And the destruction of the crystalline structure of starch is mainly achieved by disrupting the regular arrangement of the double helix, rather than directly destroying the double helix structure. High-pressure treatment significantly increases the retrogradation rate and resistant starch content. High-pressure treatment increases the apparent viscosity, yield stress, storage modulus, and loss modulus of starches. However, high-pressure treatment has different effects on the gelatinization, thermal properties, flowability index and consistency coefficient of different starches. High-pressure treatment technology has important application prospects in the preparation of R3 resistant starch and new starch materials.

The design and visualization of the distribution of atoms in a fraction of space through the application of software allows us to increase the understanding of the structure of materials and the elaboration of theoretical propositions. The purpose of this work was to develop a procedure for the application of the GeoGebra 3D software as a tool for designing crystalline structures, from the Mathematics subject for Chemical Engineering students. A workshop called GeoCristal was held to reflect experiences on the use of GeoGebra 3D. Based on a sequence of tasks, the students designed a BCC crystal structure related to alpha iron in the software. The experience demonstrated the usefulness of the software for the design of crystalline structures. It made possible to promote and systematize essential contents of Materials Engineering. Managed to increase students' motivation for Mathematics. The study reflected the importance of the use of ICTs and basic subjects in the training of chemical engineers. [ABSTRACT FROM AUTHOR]

The construction of high-performance n-type semiconductors is crucial for the advancement of organic electronics. As an attractive n-type semiconductor, molecular systems based on perylene diimide derivatives (PDIs) have been extensively investigated over recent years. Owing to the fascinating aggregated structure and high performance, S-heterocyclic annulated PDIs (SPDIs) are receiving increasing attention. However, the relationship between the structure and the electrical properties of SPDIs has not been deeply revealed, restricting the progress of PDI-based organic electronics. Here, we developed two novel SPDIs with linear and dendronized substituents in the imide position, named linear SPDI and dendronized SPDI, respectively. A series of structural and property characterizations indicated that linear SPDI formed a long-range-ordered crystalline structure based on helical supramolecular columns, while dendronized SPDI, with longer alkyl side chains, formed a 3D-ordered crystalline structure at a low temperature, which transformed into a hexagonal columnar liquid crystal structure at a high temperature. Moreover, no significant charge carrier transport signal was examined for linear SPDI, while dendronized SPDI had a charge carrier mobility of 3.5 × 10−3 cm2 V−1 s−1 and 2.1 × 10−3 cm2 V−1 s−1 in the crystalline and liquid crystalline state, respectively. These findings highlight the importance of the structure–function relationship in PDIs, and also offer useful roadmaps for the design of high-performance organic electronics for down-to-earth applications. [ABSTRACT FROM AUTHOR]

Compared to steam reforming techniques, partial oxidation of methane (POM) is a promising technology to improve the efficiency of synthesizing syngas, which is a mixture of CO and H2. In this study, partial oxidation of methane (POM) was used to create syngas, a combination of CO and H2, using the SAPO-5-supported Ni catalysts. Using the wetness impregnation process, laboratory-synthesized Ni promoted with Sr, Ce, and Cu was used to modify the SAPO-5 support. The characterization results demonstrated that Ni is appropriate for the POM due to its crystalline structure, improved metal support contact, and increased thermal stability with Sr, Ce, and Cu promoters. During POM at 600 °C, the synthesized 5Ni+1Sr/SAPO-5 catalyst sustained stability for 240 min on stream. While keeping the reactants stoichiometric ratio of (CH4:O2 = 2:1), the addition of Sr promoter and active metal Ni to the SAPO-5 increased the CH4 conversion from 41.13% to 49.11% and improved the H2/CO ratio of 3.33. SAPO-5-supported 5Ni+1Sr catalysts have great potential for industrial catalysis owing to their unique combination of several oxides. This composition not only boosts the catalyst's activity but also promotes favorable physiochemical properties, resulting in improved production of syngas. Syngas is a valuable intermediate in various industrial processes. [ABSTRACT FROM AUTHOR]

Poly(p-phenylene-2,6-benzobisoxazole) (PBO) fiber is currently one of the best-performing organic fibers; however, its low UV aging resistance limits its use. To improve the UV aging performance of PBO fibers, a novel PBO-Fe-PDA fiber was created by depositing a biomimetic structure of polydopamine (PDA) on the surface of PBO fibers with the transition metal ion Fe3+ as the active center. The surface morphology and elemental composition of PBO-Fe-PDA fibers were investigated. It was revealed that Fe3+ formed a coordination bond structure with the oxazole ring, and PDA was successfully loaded onto the surface of PBO-Fe fibers. After UV aging, the crystallinity and crystallographic orientation of PBO fibers significantly decrease, microcrystals inside the fibers slip, and the size of microvoids in the fibers rises. As a result, the strength of PBO fibers was significantly decreased after UV aging. The anti-UV aging capacity of PBO-Fe-PDA fibers, on the other hand, has been enhanced, as evidenced by a slight drop in crystallinity and crystallographic orientation and a significant decrease in the size growth of internal microvoids in the fibers after UV aging. The tensile strength retention of PBO-Fe-PDA fibers after UV aging increased by 93.13% when compared to PBO fibers without altering the fibers' initial strength. The testing results show that this surface modification method is simple to employ and extends the service life of PBO fibers significantly. [ABSTRACT FROM AUTHOR]

Copyright of Science & Technology of Food Industry is the property of Science & Technology of Food Industry Editorial Office 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 study of the tribological behavior of the braking system in auto vehicles requires knowing the characteristics of the material in contact and, in the work process, the friction pair brake disc pads. Material structural analysis is necessary because the wear process depends both on the friction-pair chemical composition (brake disc pads) and on the work process parameters (pressing force, rotational speed, traffic conditions, etc.). The material of the brake discs is generally the same, gray cast iron, and the brake pads can be semimetallic (particles of steel, copper, brass, and graphite, all united with a special resin), organic materials (particles of rubber, glass, and Kevlar, all joined with the help of a resin), composite materials that contain different constituents, and ceramic materials (rarely have small copper particles). Therefore, the purpose of this paper is to analyze the crystalline structure, tribological behavior (at friction and wear), and the mechanical properties of the materials of the brake disc–pad friction pair specific to the field through study and analysis. [ABSTRACT FROM AUTHOR]

In this article a complete procedure to investigate thin semiconductor plates (epitaxial layers), including high-resolution X-ray diffraction measurements, mathematical modelling of both crystalline structure and crystalline microstructure and computations to approximate solving inverse problems, is proposed and described in detail. The method is successfully applied to estimate crystalline homogeneity of a square indium-arsenide plate epitaxially-grown on gallium-arsenide substrate. To this end, the specimen is tested in nine areas around points forming a square grid. It is demonstrated that whole specimen may be regarded as a single large crystalline grain consisting of crystallites separated by small-angle boundaries. The crystallites occur as rode-like cuboids elongated in the direction perpendicular to the plate surface, with different areas of the sample and with base sizes not much differing. The mean-absolute second-order strain is very small and almost constant in the whole sample. The first-order strain also appears and, effectively, the structure of the crystalline layer is tetragonal with unit-cell parameters being smaller parallelly and larger perpendicularly to the layer surface and varying slightly in the layer. The results are presented in tables and figures and commented. [ABSTRACT FROM AUTHOR]

Copyright of China Synthetic Fiber Industry is the property of Sinopec Baling Petrochemical Company 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 crystalline structure and absorption spectra of thin ZnO films with different levels of B doping are studied. The films are deposited on the glass substrates using the radio-frequency magnetron sputtering without targetedsubstrates’ heating. The concentration of free charge carriers is estimated. The observed ‘blue’ shift of the fundamental absorption edge in the ZnO:B films with increasing of doping level is explained by the Burstein–Moss effect. [ABSTRACT FROM AUTHOR]

Organic solar cells (OSCs) hold immense potential as renewable energy sources, but the performance‐stability conundrum remains a major obstacle on the road to OSC commercialization. To address this, in this study, molecular packing behaviors of representative state‐of‐the‐art Y‐series non‐fullerene acceptors (NFAs) are studied, focusing on their terminal group symmetries. Utilizing grazing‐incidence wide‐angle X‐ray scattering, the distinct crystalline packing structure of these NFAs is revealed. Remarkably, NFAs with asymmetric terminals exhibited excellent additive insensitivity and thermal stability for their crystalline structure, unlike their symmetric counterparts. Molecular dynamics simulations confirmed the stable and robust crystalline feature of asymmetric NFAs and attributed to their large molecular dipole moments. These findings showed the great potential of asymmetric NFAs in fabricating efficient and intrinsically stable additive‐free OSC devices for real applications. [ABSTRACT FROM AUTHOR]

Three sweet potato varieties grew in natural high temperature (HT) and low temperature (LT) field soils. Their starch physicochemical properties were affected similarly by HT and LT soils. Compared with LT soil, HT soil induced the increases of granule size D[4,3] from 18.0–18.7 to 19.9–21.8 μm and amylopectin average branch-chain length from 21.9–23.1 to 24.1–24.7 DP. Starches from root tubers grown in HT and LT soils exhibited CA- and CC-type XRD pattern, respectively. Starches from root tubers grown in HT soil exhibited stronger lamellar peak intensities (366.8–432.0) and higher gelatinization peak temperature (72.0–76.8 °C) than those (176.2–260.5, 56.4–63.4 °C) in LT soil. Native starches from root tubers grown in LT soil were hydrolyzed more easily (hydrolysis rate coefficient 0.227–0.282 h−1) by amylase than those (0.120–0.163 h−1) in HT soil. The principal component analysis exhibited that starches from root tubers grown in HT and LT soils had significantly different physicochemical properties.

The FEM simulations of the ECAP including real conditions of the process – the friction between the metal extruded and the die walls, as well as, the channels rounding, were done here in two scales – macro- and micro-. The macroscopic analyses were done for isotopic material with a non-linear hardening using the UMAT user material procedure. The pure Lagrangian approach was applied here. The stress, strains and their increments, as well as, the deformation gradient tensor were recorded for selected finite elements in each calculation step. The displacements obtained in the macroscopic FEM analysis are then used as the kinematic input for the polycrystalline structure. The dislocation slip was included as the source of the plastic deformation here for the face-centered cubic structure. The results obtained with the use of the crystal plasticity show the heterogeneous distribution of stress and strain within the material associated with the grains anisotropy. The results in both micro- and macro- scales are coincident. The FEM analyses show the potential of the application of the crystal plasticity approach for solving elastic-plastic problems including the material forming processes.

In actual underground rock engineering, to prevent the deformation and damage of the rock mass, rock bolt reinforcement technology is commonly employed to maintain the stability of the surrounding rock. Therefore, studying the anchoring and crack-stopping effect of rock bolts on fractured granite rock mass is essential. It can provide significant reference and support for the design of underground engineering, engineering safety assessment, the theory of rock mechanics, and resource development. In this study, indoor experiments are combined with numerical simulations to explore the impact of fracture dip angles on the mechanical behavior of unanchored and anchored granite samples from both macroscopic and microscopic perspectives. It also investigates the evolution of the anchoring and crack-stopping effect of rock bolts on granite containing fractures with different dip angles. The results show that the load-displacement trends, displacement fields, and debris fields from indoor experiments and numerical simulations are highly similar. Additionally, it was discovered that, in comparison to the unanchored samples, the anchored samples with fractures at various angles all exhibited a higher degree of tensile failure rather than shear failure that propagates diagonally across the samples from the regions around the fracture tips. This finding verifies the effectiveness of the numerical model parameter calibration. At the same time, it was observed that the internal force chain value level in the anchored samples is higher than in the unanchored samples, indicating that the anchored samples possess greater load-bearing capacity. Furthermore, as the angle αs increases, the reinforcing and crack-stopping effects of the rock bolts become increasingly less pronounced.

The rapid growth of urban cities and industries has resulted in huge amounts of potentially harmful waste being released into the atmosphere. One form of hazard is noise/sound. Noise cannot be controlled in automobile industries and urban areas, which include traffic, railway stations, and markets. But it can be converted into a useful form through advanced material usage. One of the materials is piezoelectric material. Strain can be produced through vibration caused by sound, which, in turn, produces electrical energy. Hence, the objective of this research was to harvest electrical energy from hazardous sounds released from industries. Electrical energy was generated through systematic experiments using piezoelectric sensors. The experimental results revealed that the magnitude of 90 dB sound produced up to 2 volts through a single piezoelectric sensor. We can generate more energy by increasing the number of sensors as this material is cost effective. The numerical model was also effectively replicated and good agreement was obtained between the experimental and numerical frequency sound curves. [ABSTRACT FROM AUTHOR]

This study investigates the influence of poly(butadiene-isoprene) copolymer rubber (BIR) and TDAE oil on the crystallization and melting behavior of neodymium-based butadiene rubber (Nd-BR). The study demonstrates that the melting points of Nd-BR and its blends decrease with lower crystallization temperatures. Below the critical crystallization temperature (Tc,c), the melting behavior shows dual peaks in distinct temperature ranges, which are attributed to different spherulitic sizes. The addition of BIR or TDAE oil lowers the Tc,c, with TDAE oil exerting a more substantial effect. These diluents mainly influence the nucleation temperature and crystallinity level of Nd-BR while having a minimal effect on the crystallization mechanism. A master curve, which overlaps for various samples, is developed by correlating the peak melting temperature (Tm,peak) with the Tc. This curve facilitates a quantitative assessment of the effects of BIR and TDAE oil on Nd-BR, highlighting the greater influence of TDAE oil on the crystalline structure compared with BIR at equivalent mass fractions. By applying the Lorentz equation and multi-peak fitting, a relationship between the melting points and crystallization temperatures is established, enabling the calculation of the equilibrium melting points (Tm0) for different samples. The findings show a reduction in the Tm0 due to the diluents; specifically, the Tm0 is approximately 0 °C for pure Nd-BR, and it decreases to −4.579 °C and −6.579 °C for samples with 50 PHR TDAE oil and 60 wt.% BIR, respectively. [ABSTRACT FROM AUTHOR]

X-ray diffraction (XRD) and Fourier transform infrared (FT-IR) spectroscopy were used to conduct studies of both the crystalline and molecular structure of copper hexadecafluoro-phthalocyanine (F16CuPc). Bulk AC electrical conductivity and dielectric characteristics of F16CuPc were displayed in the pellet form over a temperature range of 293 K to 393 K and a frequency range of 50 Hz to 20 MHz. In this study, the universal power law σ ac ω , T = A ∘ ω S has been utilized to explain the frequency exponent response of AC conductivity. The correlated barrier hopping model (CBH) governs the AC conductivity of F16CuPc. The determination of activation energy for the alternating current process was indexed. The barrier height was discovered to be 0.25 eV according to the Giuntini model. The complex impedance Z ′ vs Z ″ was found to be semicircular. The variation of ε ′ , ε ″ as the frequency changes is also investigated. At various temperatures, the bulk of F16CuPc obtained complex permittivity and complex electric modulus. [ABSTRACT FROM AUTHOR]

Oat rice with great sensory acceptance was developed based on the combination method of milling and defatting (petroleum ether) treatment. In this study, the effect of milling and defatting treatment on the texture and digestion properties of oat rice was investigated. Results showed that milling and defatting treatment enhanced stickiness, enthalpy, and starch digestibility. The pasting temperature and hardness of oat rice were reduced. The lipid content of oat rice was significantly reduced by milling and defatting treatment, leading to a decrease in the formation of starch-lipid complex. Fourier transform infrared spectroscopy and X-ray diffraction analyses revealed that the application of milling and defatting treatments led to a reduction in the content of starch-lipid complexes in oats during the cooking process. Milling and defatting significantly enhanced both the rapid and slow digestion rates of oat rice. Specifically, the rapid digestion rate was found to be 2.5 times higher than the slow digestion rate. The nutritive components of oat rice were properly preserved, and the viscosity and elasticity of oat rice reached the maximum when milling for 40 s and defatting. This study provides a theoretical basis for oat products.

The physical modification of starch to produce resistant starch (RS) is a viable strategy for the glycemic index (GI) lowering of foods and functionality improvement in starchy food products. RS cannot be digested in the small intestine but can be fermented in the colon to produce short-chain fatty acids rather than being broken down by human digestive enzymes into glucose. This provides major health advantages, like better blood sugar regulation, weight control, and a lower chance of chronic illnesses. This article provides a concise review of the recent developments in physical starch modification techniques, including annealing, extrusion, high-pressure processing, radiation, and heat–moisture treatment. Specifically, the focus of this paper is on the alteration of the crystalline structure of starch caused by the heat–moisture treatment and annealing and its impact on the resistance of starch to enzymatic hydrolysis, as well as the granular structure and molecular arrangement of starch caused by extrusion and high-pressure processing, and the depolymerization and crosslinking that results from radiation. The impacts of these alterations on starch’s textural qualities, stability, and shelf life are also examined. This review demonstrates how physically modified resistant starch can be used as a flexible food ingredient with both functional and health benefits. These methods are economically and ecologically sustainable since they successfully raise the RS content and improve its functional characteristics without the need for chemical reagents. The thorough analysis of these methods and how they affect the structural characteristics and health advantages of RS emphasizes the material’s potential as an essential component in the creation of functional foods that satisfy contemporary dietary and health requirements.

In this study, we conduct a comparative analysis of single-beam laser annealing (SBLA) and dual-beam laser annealing (DBLA) techniques for semiconductor manufacturing. In the DBLA approach, two laser beams were precisely aligned to simultaneously heat a phosphorus-doped silicon (Si) wafer. The main objective was to investigate the impact of the two annealing techniques on the electrical properties, crystalline structure, and diffusion profile of the treated phosphorus-doped Si at equivalent laser powers. Both SBLA and DBLA improved the electrical properties of the phosphorus-doped Si, evidenced by increased carrier concentration and reduced carrier mobility. Additionally, the crystalline structure of the phosphorus-doped Si showed favorable modifications, with no defects and improved crystallinity. While both SBLA and DBLA produced similar phosphorus profiles with no significant redistribution of dopants compared to the as-implanted sample, DBLA achieved a higher activation ratio than SBLA. Although the results suggest improved dopant activation with minimal diffusion, further studies are needed to clearly confirm the effect of DBLA on dopant activation and diffusion.

With the development of 5G technology, the miniaturised and highly integrated electronic devices urgently require thermal management materials possessing high thermal conductivity and mechanical properties. In this work, isotactic polypropylene (iPP)/high-density polyethylene (HDPE)-based dielectric composites possessing ideal thermal conductivity and balanced mechanical properties were prepared via Fused Filament Fabrication (FFF). The advanced material properties were achieved by the introduction of hybrid fillers and tailored polymer crystalline structure. The highly oriented h-BN, oriented iPP crystalline and iPP/HDPE epitaxy crystalline were observed. Meanwhile, we studied the effect of the ratio of hybrid fillers on various properties of composites. The thermal conductivity of iPP/HDPE/h-BN/Al2O3 composites reach 1.802 W·m−1·K−1. The impact strength and tensile strength reach 13.23 KJ/m2 and 40 MPa, respectively. In addition, the composites maintain ideal dielectric properties. This work offers a feasible strategy to fabricate dielectric and thermal conductive composites with balanced mechanical properties using semicrystalline polymer through FFF process.

LiCo1-xNixO2 (x = 0, 0.25, 0.5, 0.75, 1) powders are synthesized using the urea; the crystalline structure and surface morphology of the prepared powders are investigated through XRD, FTIR, FE-SEM, and EDX analyses. X-ray diffraction indicates a hexagonal crystal structure for the LiCoO2 phase, Additionally, the XRD pattern of prepared LiCoO2 doped with Ni metal (x = 0.25) shows the formation of a cubic LiCoO2 nanostructure, FTIR spectra analysis of LiCoO2 and LiCo1-xNixO2 revealed several vibrational modes, such as (C=O and O–H). FESEM results indicate that all samples have nanostructure dimensions, An EDX spectrum reveals the presence of transition metals (Co) in LiCoO2, transition metals (Co and Ni) in LiCo1-xNixO2, and transition metals (Ni) in LiNiO2. [ABSTRACT FROM AUTHOR]

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Na(Nb1−xTax)O3 binary solid‐solution ceramics with high quality were fabricated by conventional solid‐state sintering routes for improving the electric(E)‐field‐induced irreversible polarization and transition behaviors of NaNbO3. The studied results confirm that this binary solid‐solution ceramics exhibit orthorhombic Pbcm space group companying with reduced unit‐cell volume at x ≤ 0.4, and orthorhombic Pbnm space group at x = 0.5. As the Ta5+ content increases in the binary solid‐solutions, the E‐field‐induced irreversible antiferroelectric → ferroelectric (AFE → FE) transition becomes reversible at x ≥ 0.2, giving rise to double‐polarization hysteresis; the key E‐fields triggering both irreversible and reversible transitions (EF) increase in general. In particular, the E‐field‐induced FE phase at x = 0.15 is unstable upon unloading E‐field to zero, which can return to AFE phase with time lapse. At x = 0.5, the Curie temperature (TC) of AFE shifts to below room temperature, but E‐field‐induced reversible transition is still observed, which results in a nonlinear polarization with the lowest hysteresis and contributes to the largest energy‐storage density. This transition is not due to the AFE ↔ FE transition but rather to the order ↔ disorder behavior of polar clusters or/and nanoregions within nonpolar Pbnm structure matrix. [ABSTRACT FROM AUTHOR]

The response performances of the crystalline organic fluorescence probe are highly dependent on the long-range ordered arrangement of crystalline structure. Herein, a novel organic crystalline fluorescent probe with a high quantum yield was established through the rapid self-assembly of 1,2,4,5-Tetrakis (4-carboxyphenyl) benzene (H4TCPB) and DMF molecules. Each H4TCPB, which connects to four DMF molecules through hydrogen bonds, acts as the structural unit. The building units are packed by π–π, lone pair···π, and lone pair···lone pair interactions to form solid-state crystalline materials. H4TCPB·4DMF exhibits distinct blue fluorescent under UV light, while the quantum yield is as high as 89.02% and the fluorescence lifetime is 1.95 ns. The H4TCPB·4DMF nanocrystal exhibits a specific fluorescence quench sensibility to tetracycline (TC), compared with the common chemicals and ions in environmental water. Moreover, the test results can be obtained quickly and are easily visible to the naked eye. The limit of detection for TC is as low as 12 nM in an aqueous solution. Spectral analysis and density functional theory (DFT) theoretical calculations were used to explain the fluorescence quenching mechanism of H4TCPB·4DMF toward TC, which could be attributed to the photoinduced electron transfer occurring from H4TCPB·4DMF to TC. Our work enriches the database of crystalline luminescent materials and provides theoretical support for the design and mechanical studies of organic fluorescent probes. [ABSTRACT FROM AUTHOR]

The FEM simulations of the ECAP including real conditions of the process – the friction between the metal extruded and the die walls, as well as, the channels rounding, were done here in two scales – macro- and micro-. The macroscopic analyses were done for isotopic material with a non-linear hardening using the UMAT user material procedure. The pure Lagrangian approach was applied here. The stress, strains and their increments, as well as, the deformation gradient tensor were recorded for selected finite elements in each calculation step. The displacements obtained in the macroscopic FEM analysis are then used as the kinematic input for the polycrystalline structure. The dislocation slip was included as the source of the plastic deformation here for the facecentered cubic structure. The results obtained with the use of the crystal plasticity show the heterogeneous distribution of stress and strain within the material associated with the grains anisotropy. The results in both micro- and macro- scales are coincident. The FEM analyses show the potential of the application of the crystal plasticity approach for solving elastic-plastic problems including the material forming processes. [ABSTRACT FROM AUTHOR]

Rare earth ion substitution is one of the most important methods for adjusting the magnetic properties of M-type hexagonal ferrites; however, the regularity of these phase formations has rarely been studied. In this work, La substituted Sr hexaferrite La x Sr 1- x O· n Fe 2 O 3 (La-SrM, 4.9 ≤ n ≤ 6.0, 0 ≤ x ≤ 0.6) was prepared using the traditional ceramic method. The effects of the Fe/Sr molar ratio (n), calcining temperature, and La3+ substitution (x) on SrM phase formation, the crystalline structure, and magnetic properties were investigated. With an increase of x up to a maximum value of 0.5–0.6, a higher calcining temperature is required to form the single M-phase of La-SrM samples. However, the optimal n values of single-phase La-SrM samples differ as the La substitution varies: when x = 0.1, n = 5.5–6.0; x = 0.2, n = 5.5–5.9; x = 0.3, 0.4 and 0.5, n = 5.7–5.8. The magnetic measurements show that La 0.2 Sr 0.8 O·5.8Fe 2 O 3 has the highest specific saturation magnetization (σ s), which is 2.2% higher than that of unsubstituted SrM (SrO·6Fe 2 O 3), while the anisotropic field (H A), the anisotropic constant (K 1), and Neel point (T N) of La3+ substituted SrM decreased. Detailed structure analyses were conducted to explain the changes in magnetic properties. Fe3+ in the spin-up 2 a sublattice of La x Sr 1- x O·5.8Fe 2 O 3 decreased by approximately 5% from 98.5% (x = 0) to 93.85% (x = 0.4) with an increase in x. Additionally, a small amount of Fe3+ was reduced to Fe2+ in the spin-down 4 f 2 sublattice with the maximum reduction amount of 4.13% reached at x = 0.2, thereby improving σ s. The decrease in the bond angle of (4 f 1) Fe3–O2–Fe5 (12 k), (2 a) Fe1–O4–Fe3 (4 f 1), and (4 f 1) Fe3–O4–Fe5 (12 k) lead to the weakening of Fe–O–Fe superexchange of La-SrM so that H A , K 1, and T n decreased with increasing values of x. This work lays a solid foundation for the study of process regulation and ion substitution of permanent magnet ferrite. [ABSTRACT FROM AUTHOR]

The goal of this study is to evaluate the influence of the concentration of silver on the structural and antimicrobial in vitro properties of silver-doped hydroxyapatite powders obtained using the precipitation method. Different concentrations of silver were evaluated to assess the antimicrobial properties. X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), Raman spectroscopy, scanning electron microscopy (SEM), and dispersive energy spectroscopy (EDS) were used to characterize the powders. XRD and FTIR showed that the hydroxyapatite structure is not affected by the incorporation of silver; on the other hand, EDS showed the presence of silver in the powders. Antibacterial studies showed the efficiency of hydroxyapatite powders in inhibiting bacterial growth as silver concentration increases. According to the results, silver-doped hydroxyapatite powders are suggested for use in the prevention and treatment of infections in bone and dental tissues. [ABSTRACT FROM AUTHOR]