Classifying Grains Using Behaviour-Informed Machine Learning

Sorting granular materials such as ores, coffee beans, cereals, gravels and pills is essential forapplications in mineral processing, agriculture and waste recycling. Existing sorting methods are based on the detection of contrast in grain properties including size, colour, density and chemical composition. However, many grain properties cannot be directly detected in-situ, which significantly impairs sorting efficacy. We show here that a simple neural network can infer contrast in a wide range of grain properties by detecting patterns in their observable kinematics. These properties include grain size, density, stiffness, friction, dissipation and adhesion. This method of classification based on behaviour can significantly widen the range of granular materials that can be sorted. It can similarly be applied to enhance the sorting of other particulate materials including cells and droplets in microfluidic devices.

The Water-ice Feature in Near-infrared Disk-scattered Light around HD 142527: Micron-sized Icy Grains Lifted up to the Disk Surface?

We study the 3 μm scattering feature of water ice detected in the outer disk of HD 142527 by performing radiative transfer simulations. We show that an ice mass abundance at the outer disk surface of HD 142527 is much lower than estimated in a previous study. It is even lower than inferred from far-infrared ice observations, implying ice disruption at the disk surface. Next, we demonstrate that a polarization fraction of disk-scattered light varies across the ice-band wavelengths depending on ice grain properties; hence, polarimetric spectra would be another tool for characterizing water-ice properties. Finally, we argue that the observed reddish disk-scattered light is due to grains a few microns in size. To explain the presence of such grains at the disk surface, we need a mechanism that can efficiently oppose dust settling. If we assume turbulent mixing, our estimate requires α ≳ 2 × 10−3, where α is a nondimensional parameter describing the vertical diffusion coefficient of grains. Future observations probing gas kinematics would be helpful to elucidate vertical grain dynamics in the outer disk of HD 142527.

Porous and cracked rocks elasticity: Macroscopic poroelasticity and effective media theory

Macroscopic poroelasticity and effective medium theory are two independent approaches which can be used to analyze the role of pores, cracks, and fluid on elastic properties. Macroscopic poroelasticity belongs to the macroscopic framework of thermodynamics whereas effective medium theory expresses the medium properties in terms of microstructural characteristics (pore and crack shape, etc.) and component properties (fluid properties, solid grain properties, etc.). In this paper, we review the fundamental assumptions and results of both approaches, and show that they are complementary but do not apply over the same range of conditions. A compilation of data is reported, in various dry and saturated rocks, to show the validity of the Gassmann equation and the dispersion between unrelaxed modulus –where effective medium model applies- and relaxed modulus –where poroelasticity applies.

An innovative approach for determining composite wheat quality index to identify quality enriched genotypes - insights and implications

Ranking test entries or test sites on a quality basis is very difficult in wheat as value addition is perceived by several grain properties and end-products. Here, a novel approach has been developed and tested by deriving wheat quality index based on principal component analysis of 13 physico-chemical grain parameters and 3 end products of 45 wheat varieties. Depending upon the observed index range (0.15 to 0.71), the cultivars were assorted into 3 distinct classes i.e. elite, moderate and poor. The top group ascertained high quality standards of grain suited for bread and chapati whereas bottom group assured better cookies quality. This technique was also tested to differentiate quality enriched test sites within a zone or demarcate the most suited production environments to harness good quality wheat. The index will have an implication on farmers (premium price for varietal segregation), industry (product specific quality cultivars), and consumers (superior quality products).

Delayed sedimentary grains

<p>River sediment grains are transported and stored episodically in different reservoirs (terraces, alluvial fans, foreland basin, etc.). The residence time of sediment grains in each reservoir has important implications for the paleo-environmental interpretation established from these grains, and their stratigraphic record, as well as for soil contamination, when these grains come from contaminated sources. The recycling of old sediments, via erosion of an old reservoir (e.g. foreland basin erosion), is a known problem. What is less well recognised is that the recycling of a minority of very old grains can strongly bias the average residence time of a grain population deposited in a stratum. In this case, the time-dependent paleo-environmental properties of a population of grains, such as the degree of weathering, or the concentration of cosmogenic isotopes, can then be biased. Several lines of evidence for this phenomenon, inherent to fluvial transport processes, have emerged, though reconstructing the residence time distribution of a grain population over long times (>>ka) remains a challenge. Using a landscape evolution model coupled with grain transport, we show that at the scale of a piedmont, grains can remain several hundred ka before being evacuated. At the scale of a river in Northern Chile, we used the concentration of 10Be in individual pebbles to show that some pebbles remain stored for several tens of ka before being evacuated to the river outlet. In addition, the distribution of residence times can also provide information on the nature of the diffusive processes that control the fluxes of exported sediment. These results suggest that the characterisation of grain-by-grain properties in a grain population can not only help to avoid possible interpretation biases but also provide constraints for models of long-term fluvial sediment outfluxes.  </p>

Variations of grain physical properties, amylose and anthocyanin of upland red rice cultivars from East Nusa Tenggara, Indonesia

Markus JER, Ndiwa ASS, Oematan SS, Mau YS. 2021. Variations of grain physical properties, amylose and anthocyanin of upland red rice cultivars from East Nusa Tenggara, Indonesia. Biodiversitas 22: 1345-1354. Red rice is becoming more popular nowadays due to the increasing awareness of rice consumers on its health benefits. The demands for red rice are increasing but the supply is limited, thus, local red rice cultivars can be used to fill this gap. Optimal use of local rice germplasm requires a comprehensive evaluation of their traits, and the genotypes having the most desirable traits can be selected for direct use. Several upland red rice cultivars from East Nusa Tenggara Province have been evaluated for various traits while their grain properties are still unrevealed. Information on grain properties is important, both for consumer preference and rice breeders. This study aimed to elucidate the grain physical properties, amylose, and anthocyanin of upland red rice germplasm from ENT Province, and to identify genotypes with the most desirable characters for further employment. Eighteen rice genotypes were used in this study. They were cultivated in the field, and the harvested grains were analyzed in the laboratory. Both ANOVA and descriptive statistics were used for data analysis. Substantial variations were observed on all variables, except the chalky grain percentage. The kernel length of tested genotypes was classified as long, medium, and short while the kernel shapes were slender, medium, and bold. Most tested genotypes had high head rice percentage and low to medium percentages of large and small broken kernels. Chalky grain was almost absent. Amylose content ranged from 1.0% to 28% while anthocyanin was about 1.0 - 20 mg/100 g. The evaluated genotypes were clustered into three main groups. Percentages of large and small broken kernels, and amylose content were mostly responsible for the observed variations among the rice genotypes. The red rice genotypes were diverse in the studied characters, thus, those with desirable grain characters are useful for further development and utilization.

FEATURES OF GRAIN MOISTUREAUTOMATED MEASUREMENTIN FIELD CONDITIONS

The article discusses ways to Mature grain properties and describes its behavior during harvesting, to optimize the selection of grain moisture state, and also analyzes the requirements for the selection of methods and design of a high-frequency module, which provides for the use of instrumentation for monitoring grain moisture, as well as their high accuracy and the possibility of conducting measurements in the field.

Planar column collapse of elongated grains

The granular column collapse is a benchmark configuration for the study of granular flows in dry, saturated, and submerged conditions. The collapse sequence and resultant mobility is acknowledged to be controlled by the column aspect ratio, while grain properties define the relative transition of each stage. Grain shape effects are found to modify the global shear resistance of granular media, with a strong and coupled interaction when interacting with a fluid. In this work, we present the first steps towards the study of grain shape effects in a column collapse when interacting with an ambient fluid. For this purpose, we use a planar configuration and explore the collapse of a column consisting of rod-like grains and study the initial and after collapse grain orientations. On it, the mobilized grains deposit in a preferential horizontal orientation, but further experiments are required to confirm if a nematic configuration can be achieved.

Verschleißmechanismen von CBN-Körnern/Wear mechanisms of CBN grains – Studies to identify and quantify CBN grain wear mechanisms

Dieser Beitrag stellt die Ergebnisse von Verschleißuntersuchungen beim Einkornritzen mit CBN-Körnern dar. Der Fokus der Forschungsarbeit liegt auf der Identifizierung und Quantifizierung der Verschleißmechanismen in Abhängigkeit von den Prozesseinstellgrößen und den Korneigenschaften. Es werden charakteristische Phasen der Verschleißentwicklung identifiziert, die eine Zuordnung der Verschleißmechanismen Mikrobruch, Makrobruch und Abrasion zulassen.   The content of the paper is the presentation of the results of wear investigations on CBN grains used in single grain scratching. The focus of the research work is on the identification and quantification of the wear mechanisms as a function of the process parameters and the grain properties. Characteristic phases of wear development were identified, which allow an allocation of the wear mechanisms micro fracture, macro fracture and abrasion.