Ideal Grain Research Articles

Numerical simulation and experimental researches on different abrasive grain arrangements of monolayer diamond grinding tools fabricated by HFCVD method

The hot filament chemical vapor deposition (HFCVD) method has been used to fabricate monolayer diamond grinding tools, whose abrasive grain arrangements can be achieved by patterned masks. The orderly arrangement pattern of abrasive grains can improve the grinding trajectory density of abrasive grains and reduce the workpiece surface roughness. In this study, the numerical simulation method is used to investigate the effect of abrasive grain pattern arrangements on the grinding trajectories and ground surface topographies, including Archimedes spiral, concentric circular, phyllotactic, disordered, and staggered patterns. The simulation results indicate that the grinding trajectory is most uniform and dense when applying the staggered pattern arrangement, and the workpiece surface roughness is lower than that of the other pattern modes. Then monolayer diamond grinding tools with five types of abrasive grain patterns are fabricated on the SiC substrate by HFCVD method. The grinding tool surface has a complete grain pattern and as-grown diamond film on the substrate is homogeneous in thickness, which is regarded as the bonding layer of the abrasive tools. EDS carbon element mapping and Raman spectra analysis reveal that the as-grown diamonds, both on substrates and seeds, exhibit high quality. Grinding experiments are performed utilizing CVD diamond grinding tools. The ground surface with a staggered pattern exhibits the lowest surface roughness without periodic grinding bands, as is consistent with the simulation results. Besides, the graphitization evaluation and worn feature statistics show that abrasive grains are of low levels of graphitization and high quantity of dynamic active grains as well as have slight abrasive grain wear and large chip space applying staggered pattern, which is the ideal abrasive grain arrangement pattern.

Multiplicity of grain boundary structures and related energy variations

Ideal minimum-energy grain boundary (GB) structures are usually the only ones considered when characterizing GBs. This limited perspective provides an incomplete view of the possible structural variability of GBs. In the present study, phase field crystal (PFC) simulations are employed in a systematic search of GB states based on γ-surface sampling, demonstrating PFC to be a capable tool for this purpose. It is also shown that a set of microscopic degrees of freedom (DOF) must be considered in addition to the GB’s five macroscopic DOF when identifying variants in GB structure. This set of microscopic DOF comprises three components of relative crystal translation, plus one DOF describing the atomic density in the GB region. GB energy is taken as an example of a key property which is shown to exhibit a considerable spread due to variations in these microscopic DOF, at constant macroscopic DOF. The findings underline the need to consider a spectrum of GB energies for each macroscopic GB configuration, rather than a single value corresponding to an idealized minimum-energy structure. As part of the study, some computationally efficient strategies for setting up the PFC simulation model are also proposed.

Pine-to-Bioenergy: Potential of pine sap as adhesive and pine flower biomass waste in the production of biobriquettes

Pine-flower biomass waste is abundant, but its utilization is still lacking. This research converts pine-flower waste into biobriquettes by using pine resin adhesive. This study aims to identify the effect of pine resin adhesive concentration and the effect of grain size on the quality of the resulting biobriquettes. The production of biobriquettes begins by processing pine flower waste into biochar using the pyrolysis method at 400 °C. Biochar from pinecones was ground and sieved into sizes (250, 500, and 750 µm). Then proximate analysis (moisture content, ash content, volatile matter, fixed carbon), and heating value were performed. Making biobriquettes using pine resin adhesive with different concentrations (5, 10, and 15%) of the total mixture According to the results, the ideal grain size was 750 m, the adhesive concentration was 15%, and the moisture content, ash content, volatile matter content, fixed carbon content, and heating value were all respectively 2.23%, 4.51%, 30.23%, 70.04%, and 23.34 MJ/kg, and the longest flame was also determined to be 0.0250 g/sec. All of them comply with universally accepted biobriquette standards (Indonesian National Standard 01–6235–2000), Japanese, English, and ISO 17225. Biobriquettes have potential applications in bioenergy products. Investigation of the economic feasibility of biobriquette production seen from Profit on Sales is 26.43%, Rate on Investment is 34.00%, Pay Out Time is 2.47 years, and Break Event Point is 49.22%.

Heterologous expression of SpsLAZY1a in Populus enhanced the sensitiveness of plant architecture

Plant tiller angle is a key agronomic trait that contributes to ideal plant architecture and grain production. However, the molecular mechanism regulating branch angle and plant architecture has not been fully explored in Salix psammophila. Here, we found that the natural germplasm of S. psammophila has a different plant architecture and determined that SpsLAZY1a participated in the control of agronomical traits. SpsLAZY1a was mainly expressed in the stem. SpsLAZY1a transformed with heterologous overexpression in poplar caused distortion at the base of the stem, increased the number of branches and influenced the sensitivity to gravity of the plant. Furthermore, SpsLAZY1a overexpression plants accumulated less auxin and cytokinin than the control. Transcriptome sequencing showed that the overexpression of SpsLAZY1a caused the differential expression of related genes in the plant hormone signal transduction, starch and sucrose metabolism pathways. The expression level of SpsLAZY1a can be rapidly induced by auxin. Taken together, we discovered the key genes related to S. psammophila plant architecture, which provided a basis for further research on the development of tree architecture.

Natural variation in Tiller Number 1 affects its interaction with TIF1 to regulate tillering in rice.

Tiller number per plant-a cardinal component of ideal plant architecture-affects grain yield potential. Thus, alleles positively affecting tillering must be mined to promote genetic improvement. Here, we report a Tiller Number 1 (TN1) protein harbouring a bromo-adjacent homology domain and RNA recognition motifs, identified through genome-wide association study of tiller numbers. Natural variation in TN1 affects its interaction with TIF1 (TN1 interaction factor 1) to affect DWARF14 expression and negatively regulate tiller number in rice. Further analysis of variations in TN1 among indica genotypes according to geographical distribution revealed that low-tillering varieties with TN1-hapL are concentrated in Southeast Asia and East Asia, whereas high-tillering varieties with TN1-hapH are concentrated in South Asia. Taken together, these results indicate that TN1 is a tillering regulatory factor whose alleles present apparent preferential utilization across geographical regions. Our findings advance the molecular understanding of tiller development.

Non-self-similar grain growth by zero-temperature Potts model

Self-similar coarsening, a well-researched aspect of normal grain growth, is a key component of grain growth theories and visible in mesoscopic simulations of ideal grain growth. One particular simulation algorithm is the Potts model, which can be used to perform a thorough investigation of the temporal evolution of polycrystalline microstructures. Used with carefully selected parameters, the Potts model recreates normal grain growth quite accurately. One specific feature necessary to reach this goal is the simulation temperature, i.e. simulation thermal energy. It prevents grain boundaries from aligning along the underlying simulation lattice. Nevertheless, there are still today many researchers who implement classical zero-temperature Potts model simulations—often for reasons of simplification and/or modeling speed. In the current study, we show in detail the negative effect of setting the simulation temperature to zero. As a result, a unique type of non-self-similar coarsening is observed, where, e.g. the von Neumann–Mullins-relation shows unexpected time-dependent behavior. Hence, this study can be understood as a blueprint on why not to use a zero-temperature Potts model.

Thin lamellar Li7La3Zr2O12 solid electrolyte with g-C3N4 as grain boundary modifier for high-performance all-solid-state lithium battery

Inorganic superionic conductors hold great promise for all-solid-state lithium battery. However, the ionic conductivity of developed inorganic solid electrolytes (ISEs) is often insufficient owing to the enormous grain boundary resistance and large thickness. Herein, a 30 μm-thick Li7La3Zr2O12 (LLZO) lamellar inorganic solid electrolyte (LLZO/CN LISE) is fabricated by assembling LLZO nanosheets into lamellar framework, followed by in-situ growing g-C3N4 in the interlayer spacing. Based on the regular and unambiguous lamellar structure, g-C3N4 is found to be an ideal grain boundary modifier, and the Li-ion transfer process at grain boundary is thus investigated in detail. We demonstrate that this LLZO/CN LISE achieves an ultralow grain boundary resistance (<12.3 Ω cm2vs. 1608 Ω cm2 for LLZO pellet) and hence high ionic conduction properties (the ionic conductivity is 2.50 × 10−4 S cm−1 and the ionic conductance is 167 mS at 25 °C). The assembled Li symmetrical cell can stably cycle over 1500 h at 0.2 mA cm−2 and 60 °C. The assembled LiFePO4|Li cell also exhibits excellent cycling performances with a discharge capacity of 147.7 mAh g−1 at 0.5C and 60 °C after 150 cycles. This insight should present new opportunities in designing and developing high-performance ISEs.

Fast and accurate wheat grain quality detection based on improved YOLOv5

Ideal wheat grain quality detection systems aim for rapid and precise recognition of flaws. Computer vision and machine learning have been widely studied as potential alternatives to human inspection. Numerous deep learning-based detection and classification methods have been proposed in the last few years. However, these methods suffer from poor performance and extremely long time consumption due to the weak feature extraction ability and high computational overhead. To solve these challenges, we present the first comprehensive study and analysis of wheat grain detection using improved YOLOv5. Specifically, we design a machine vision system and construct a Wheat Grain Detection Benchmark (WGDB) including 1746 images with 7844 bounding boxes, all of which have been independently classified. Utilizing this dataset, we conduct a comprehensive study of the most advanced objection detection methods. In addition, we propose a Wheat Grain Detection Network (called WGNet) trained on this benchmark as a baseline, aiming to solve the degradation issues by employing sparse network pruning and a hybrid attention module. Extensive experiments demonstrate the limitations of existing methods and the improved performance of our method, which achieves state-of-the-art precision with the fastest inference speed. The constructed benchmark and the improved experiments shed light on future research in wheat grain detection. The dataset and code will be available at WGNet.

Viscosity, Total Acid, Protein and Hedonic Level of Kefir Made from Buffalo Milk with Different Concentration of Kefir Grain

This research aims to determine the effect of different kefir grain concentration to viscosity, total acid, protein and hedonic level of buffalo milk kefir and to determine the ideal kefir grain concentration for buffalo milk kefir. The basic ingredients used in this research were buffalo milk and kefir grain. Concentration of kefir grain at 2.5%, 5%, 7.5%, 10% (g/v) was used to measure viscosity, total acid, protein and hedonic level of buffalo milk kefir. Ostwald pipette and pycnometer were used to determine the viscosity, total acid used titration method with NaOH 0.1 N, destruction and distillation methods were used to determine the protein content and the hedonic test were done by 25 panelists. The results show that different levels of kefir grain concentration gave significant effect (p&lt;0.05) on every parameter. Various levels of kefir grain concentration had highly significant effect (p&lt;0.05) on kefir as a product. The conclusions from this study are the more addition of kefir grain, the more viscosity, total acid, and protein content. From the hedonic test gave specific results in sour taste, aroma, texture and overall.

Origin of fine equiaxed grains in industrial low-temperature grain-oriented silicon steel normalized sheet and their influence on magnetic properties

In the industrial low-temperature grain-oriented (LTGO) silicon steel normalized sheet, there are a certain number of fine equiaxed grains distributed along the rolling direction. However, the formation mode of the fine equiaxed grains and the influence of them on magnetic properties have not yet been well understood. In the present work, the above issues were investigated using field emission scanning electron microscopy (SEM), field emission transmission electron microscopy (TEM), X-ray diffraction (XRD), high temperature confocal scanning laser microscopy (HTCSLM), etc. It was found that (1) the fine equiaxed grains could be divided into many grain colonies according to grain orientation, and within each colony, the grain orientations were similar; (2) during normalizing, the fine equiaxed grains were mainly generated inside the elongated deformed grains which contained a large number of subgrains; (3) the amount of α → γ phase transformation during the normalizing was very small. Therefore, it can be inferred that the fine equiaxed grains were mainly produced by subgrain coalescence, rather than by phase transformation. Moreover, γ-grain (〈111〉 // ND) colonies with ideal grain size could be formed in the fine equiaxed grain regions after ideal normalizing process. Due to the heredity of microstructure and texture, γ-grain colonies, which can facilitate the formation of the precise Goss texture ({110} 〈001〉 ) during high-temperature annealing, were formed in the primary recrystallized matrix after cold rolling, decarburizing and nitriding, as a result, the magnetic properties of the final product were significantly improved. The present work can provide help to further improve the understandings of the microstructural evolution in the LTGO silicon steel normalized sheet and the influence of normalized microstructure on magnetic properties.

Constant of motion for ideal grain growth in three dimensions

Most metallic and ceramic materials are comprised of a space-filling collection of crystalline grains separated by grain boundaries. While this grain structure has been studied for more than a century, there few rigorous results regarding its global properties available in the literature. We present a new, rigorous result for three-dimensional grain structures that relates the integral of the Gaussian curvature over the grain boundaries to the numbers of grains and quadruple junctions. The result is numerically verified for a grain structure consisting of periodic truncated octahedra.

Remote-Sensing-Combined Haplotype Analysis Using Multi-Parental Advanced Generation Inter-Cross Lines Reveals Phenology QTLs for Canopy Height in Rice.

High-throughput phenotyping systems with unmanned aerial vehicles (UAVs) enable observation of crop lines in the field. In this study, we show the ability of time-course monitoring of canopy height (CH) to identify quantitative trait loci (QTLs) and to characterise their pleiotropic effect on various traits. We generated a digital surface model from low-altitude UAV-captured colour digital images and investigated CH data of rice multi-parental advanced generation inter-cross (MAGIC) lines from tillering and heading to maturation. Genome-wide association studies (GWASs) using the CH data and haplotype information of the MAGIC lines revealed 11 QTLs for CH. Each QTL showed haplotype effects on different features of CH such as stage-specificity and constancy. Haplotype analysis revealed relationships at the QTL level between CH and, vegetation fraction and leaf colour [derived from UAV red–green–blue (RGB) data], and CH and yield-related traits. Noticeably, haplotypes with canopy lowering effects at qCH1-4, qCH2, and qCH10-2 increased the ratio of panicle weight to leaf and stem weight, suggesting biomass allocation to grain yield or others through growth regulation of CH. Allele mining using gene information with eight founders of the MAGIC lines revealed the possibility that qCH1-4 contains multiple alleles of semi-dwarf 1 (sd1), the IR-8 allele of which significantly contributed to the “green revolution” in rice. This use of remote-sensing-derived phenotyping data into genetics using the MAGIC lines gives insight into how rice plants grow, develop, and produce grains in phenology and provides information on effective haplotypes for breeding with ideal plant architecture and grain yield.

Three-dimensional large-scale grain growth simulation using a cellular automaton model

The mechanical properties of metallic materials are highly dependent on the average and distribution of the grain size. Therefore, it is important to accurately understand grain growth behavior, and numerical simulations play an important role in this regard. Accordingly, in this study, a three-dimensional cellular automaton (3DCA) grain growth model was developed using a simple grain boundary curvature model and the stochastic transition rule as a CA algorithm. To validate this model, a large-scale 3DCA simulation of the ideal grain growth was performed, and the obtained results were compared with those of the ultra-large-scale phase-field (PF) simulation and other analytical models. The grain coarsening during the simulation followed a parabolic law, and the distributions of the normalized grain radius and number of grain faces were transformed to steady-state distributions over time. Moreover, the relationship between the normalized grain size and the normalized growth rate was in good agreement with the Hillert theory for the normalized grain sizes of 0.2–2.2. The simulation results were similar to the ultra-large-scale PF simulation data, in which grains remained in the steady state on a statistically reliable scale. Finally, the established relationships between the normalized growth rate, the normalized grain size, and the number of grain faces were in good agreement with the analytical model. Our results indicate that the grain growth behavior can be quantitatively predicted by the proposed 3DCA model. The calculation time required for this simulation (15000 steps with 10003 grids) was about 2.4 d using a personal desktop computer with 1 CPU. From the comparison with ultra-large scale PF simulations, we estimated that this 3DCA model has the potential to calculate >10 times faster than the PF method.

Optimizing the strength and ductility of Cu–Al alloy by an ideal grain structure

Here an ideal grain structure, with short dislocation-slip path and low dislocation density, is fabricated in a Cu–Al alloy by combining equal channel angular pressing and cold rolling at liquid nitrogen temperature and subsequent annealing at 350 °C. The microstructure of this ideal structure is characterized by fine recrystallized grains in size of a few micrometers with abundant nanotwins and high angle grain boundaries. Accordingly, a good strength-ductility synergy combining a yield strength of 475 MPa and a uniform elongation of about 27.9% is obtained in tensile test. The transmission electron microscopy (TEM) examinations revealed effective hindering of dislocations by twin boundaries and storage of dislocations inside grains, which are responsible for the excellent strain hardening capability. This study provides a promising grain structure for industrial application.

Evaluation of mechanical properties of concrete produced with binary and ternary mixtures of aggregate

Cement is the costlier component of concrete, and its productive process causes considerable environmental impact. Thus, alternatives are studied to reduce the amount of cement used. An option is the use of optimized grain size curves of aggregates, aiming to achieve a higher compactness of concrete. An ideal grain size distribution results in a higher mechanical resistance of concrete, providing a reduction in cost and consumption of materials, and, consequently, in environmental impacts. Therefore, the present study aims to improve the properties of conventional concrete through optimized grain size distributions. In this research, concrete was produced with binary mixtures with rolled pebbles from Belém region, in Pará state, and ternary mixtures of granitic crushed stone from the metropolitan region of Recife, in Pernambuco state, and concrete properties in the hardened state were studied. The mix design IPT/EPUSP method was used and grain size composition, unit weight, water absorption by capillarity, and compressive strength tests were performed. It was observed an increase in compressive strength with for higher fine contents. Furthermore, for both aggregates studied, there was no loss in strength with the lower amount of cement used, due to the increased compactness of the concrete, indicated by the unit weight of the aggregate mixture. Therefore, the optimization of the grain size composition of the coarse aggregate provided a reduction in the cement consumption for the same required strength and for both analysed aggregates.

Improvement of edge crack damage of magnesium alloy by optimizing the edge curve during cross variable thickness rolling

According to the MAS rolling and cross rolling theory, the hot rolling experiments were carried out on the AZ31 magnesium alloy specimens at the initial rolling temperature of 350 °C, and the grain distribution and edge damage of the strip after rolling by a controlled rolling reduction in different regions were analyzed. Meanwhile, the edge curves were designed to improve the edge crack and grain refinement of magnesium alloy during cross variable thickness rolling. The results indicated that the variable thickness rolling with the edge curve could effectively reduce the edge crack of magnesium alloy. The results also indicated that different edge curves could produce varying degrees of grain refinement at the strip edge and realize the ideal grain refinement in different regions during the rolling process; meanwhile, the optimization of the edge curve during cross variable thickness rolling could provide a theoretical basis for improving the magnesium alloy edge crack.

Triple-junction morphology classification and dihedral angle distribution during 2D grain growth

We analyzed and classified the grain structure in the vicinity of triple junctions during an ideal 2D grain growth process. We used the multi-order parameter phase-field grain-growth model to generate the grain structures and evaluated the distribution of the dihedral angles between the grain boundaries at triple junctions. The triple junctions were classified based on the microstructure represented by the sharp-interface representation, and the dihedral angles were estimated using the angle between the gradient of the order parameters. The average value was 120°. We also observed that the peak position of the angle distribution was less than 120°. However, the distributions of the three most frequent major classes showed a peak at 120° or a plateau region between 110° and 130°. These observations are explained on the basis of force-balance analysis at the triple junctions.

Role of lanthanum in microstructure evolution and enhanced magnetic properties of cerium‐containing sintered magnets

AbstractIn this study, lanthanum was applied to strip cast Ce−Fe−B alloy to improve its phase composition and microstructure. The results reveal that lanthanum doping can significantly enhance the proportion of 2 : 14 : 1 phase and improve the microstructure of Ce−Fe−B alloy. Besides, the influence of the starting alloys structure on the microstructure and magnetic properties of final multi‐phases cerium‐containing magnets was also systematically investigated. Compared to the multi‐phases magnet without lanthanum addition, a pronounced coercivity increment could be distinguished in lanthanum‐doping multi‐phases magnet, which could be attributed to the finer grain size together with ideal grain boundary. In this work, the superior performance of Hcj = 701.28 kA/m Br = 1.30 T, and (BH)max = 313.70 kJ/m3 were obtained by blending Nd−Fe−B alloy with (La0.35Ce0.65)‐Fe−B alloy to meet 25.0 wt.% lanthanum‐cerium utilization content, suggesting that the possibility to develop high abundant rare earth permanent magnetic materials.

Dosimetric behavior of modified borate bioglass containing copper for low photon dose measurements using luminescence characteristics

Presented work deliberate the dosimetric impact of low absorbed dose in modified borate bioactive glass as utilization for such newly studied material. The particle size impact, glow curve, relative response to different doses, and dose fading impact was examined as thermoluminescence (TL) properties moreover. Thermoluminescence investigations of borate bioglass containing copper oxide irradiated by γ-ray demonstrated a conspicuous TL glow peak maximum at 353 °C. The TL emission peak due to defects identified with the host material. The outcoming results are concerned with their uses in low dose dosimetry. The outcoming showed that the ideal grain size is extended between 53 and 106 µm.), respecting to glow peak of borate bioactive glass after gamma irradiation from gamma radiation cobalt source, three unresolved glow peaks was founded. The linear relationship response curve in the portion runs from 0.1 up to 1.5 Gy. The absolute TL-signal seems to be constant through 30 days of storage of the modified samples. Peaks activation energies were calculated through TL kinetics in deep traps, which recommended store the TL-signal. The low detected with a threshold value (0.01 Gy) fusing with this strategy represented as a good radiation sensitivity making it permissible to use for individual accidental retrospective. However, in the case of a personal dosimeter, Good and helpful data can be gotten on. Treatment would then be able to be founded on this data moreover.

S-PFM model for ideal grain growth

The phase-field method is increasingly used for studying grain growth in metallic alloys. Such an approach offers a thermodynamically consistent framework for studying microstructure evolution during grain growth without the need to explicitly track the interface positions. However, the numerical solution of the models requires a grid spacing much smaller than the interface width. This leads to computationally very intensive simulations, especially when a large number of grains is required to accurately measure statistical quantities. The recently proposed S-PFM approach provides a new inherently discrete formulation of phase field models where the interface width can be as small as the grid spacing, thus drastically improving the numerical performances of the method. Here, we show that this approach can be extended to a multi-phase field model for ideal grain growth. Then, we perform two dimensional simulations to analyse in detail the kinetics of both grain boundaries and triple junctions. We compare our model to a classical phase field formulation and we demonstrate that, for a prescribed accuracy, the memory requirement and simulation times are both reduced by a factor of 4D, where D is the space dimension. Finally, we perform a large-scale simulation of grain growth in two dimensions and show that the method is able to reveal the specific shape of the grain size distribution in the scale-invariant regime displaying two peaks around the mean grain size and quantitative measurements of the underlying topological classes are performed.