⁴⁰Ar/³⁹Ar dating of a hydrothermal pegmatitic buddingtonite–muscovite assemblage from Volyn, Ukraine

We determined 40Ar/39Ar ages of buddingtonite, occurring together with muscovite, with the laser-ablation method. This is the first attempt to date the NH4-feldspar buddingtonite, which is typical for sedimentary–diagenetic environments of sediments, rich in organic matter, or in hydrothermal environments, associated with volcanic geyser systems. The sample is a hydrothermal breccia, coming from the Paleoproterozoic pegmatite field of the Korosten Plutonic Complex, Volyn, Ukraine. A detailed characterization by optical methods, electron microprobe analyses, backscattered electron imaging, and IR analyses showed that the buddingtonite consists of euhedral-appearing platy crystals of tens of micrometers wide, 100 or more micrometers in length, which consist of fine-grained fibers of ≤ 1 µm thickness. The crystals are sector and growth zoned in terms of K–NH4–H3O content. The content of K allows for an age determination with the 40Ar/39Ar method, as well as in the accompanying muscovite, intimately intergrown with the buddingtonite. The determinations on muscovite yielded an age of 1491 ± 9 Ma, interpreted as the hydrothermal event forming the breccia. However, buddingtonite apparent ages yielded a range of 563 ± 14 Ma down to 383 ± 12 Ma, which are interpreted as reset ages due to Ar loss of the fibrous buddingtonite crystals during later heating. We conclude that buddingtonite is suited for 40Ar/39Ar age determinations as a supplementary method, together with other methods and minerals; however, it requires a detailed mineralogical characterization, and the ages will likely represent minimum ages.

Non-Contact Optical Detection of Foreign Materials Adhered to Color Filter and Thin-Film Transistor

This paper describes the non-contact optical detection of debris material that adheres to the substrates of color filters (CFs) and thin-film transistors (TFTs) by area charge-coupled devices (CCDs) and laser sensors. One of the optical detections is a side-view illumination by an area CCD that emits a coherency light to detect debris on the CF. In contrast to the height of the debris material, the image is acquired by transforming the geometric shape from a square to a circle. As a result, the side-view illumination from the area CCD identified the height of the debris adhered to the black matrix (BM) as well as the red, green, and blue of a CF with 95, 97, 98, and 99% accuracy compared to the golden sample. The uncertainty analysis was at 5% for the BM, 3% for the red, 2% for the green, and 1% for the blue. The other optical detection, a laser optical interception with a horizontal alignment, inspected the material foreign to the TFT. At the same time, laser sensors intercepted the debris on the TFT at a voltage of 3.5 V, which the five sets of laser optics make scanning the sample. Consequently, the scanning rate reached over 98% accuracy, and the uncertainty analysis was within 5%. Thus, both non-contact optical methods can detect debris at a 50 μm height or lower. The experiment presents a successful design for the efficient prevention of a valuable component malfunction.

Correlative imaging of ferroelectric domain walls

The wealth of properties in functional materials at the nanoscale has attracted tremendous interest over the last decades, spurring the development of ever more precise and ingenious characterization techniques. In ferroelectrics, for instance, scanning probe microscopy based techniques have been used in conjunction with advanced optical methods to probe the structure and properties of nanoscale domain walls, revealing complex behaviours such as chirality, electronic conduction or localised modulation of mechanical response. However, due to the different nature of the characterization methods, only limited and indirect correlation has been achieved between them, even when the same spatial areas were probed. Here, we propose a fast and unbiased analysis method for heterogeneous spatial data sets, enabling quantitative correlative multi-technique studies of functional materials. The method, based on a combination of data stacking, distortion correction, and machine learning, enables a precise mesoscale analysis. When applied to a data set containing scanning probe microscopy piezoresponse and second harmonic generation polarimetry measurements, our workflow reveals behaviours that could not be seen by usual manual analysis, and the origin of which is only explainable by using the quantitative correlation between the two data sets.

Smart knife: technological advances towards smart cutting tools in meat industry automation

Purpose Modern meat processing requires automation and robotisation to remain sustainable and adapt to future challenges, including those brought by global infection events. Automation of all or many processes is seen as the way forward, with robots performing various tasks instead of people. Meat cutting is one of these tasks. Smart novel solutions, including smart knives, are required, with the smart knife being able to analyse and predict the meat it cuts. This paper aims to review technologies with the potential to be used as a so-called “smart knife” The criteria for a smart knife are also defined. Design/methodology/approach This paper reviews various technologies that can be used, either alone or in combination, for developing a future smart knife for robotic meat cutting, with possibilities for their integration into automatic meat processing. Optical methods, Near Infra-Red spectroscopy, electrical impedance spectroscopy, force sensing and electromagnetic wave-based sensing approaches are assessed against the defined criteria for a smart knife. Findings Optical methods are well established for meat quality and composition characterisation but lack speed and robustness for real-time use as part of a cutting tool. Combining these methods with artificial intelligence (AI) could improve the performance. Methods, such as electrical impedance measurements and rapid evaporative ionisation mass spectrometry, are invasive and not suitable in meat processing since they damage the meat. One attractive option is using athermal electromagnetic waves, although no commercially developed solutions exist that are readily adaptable to produce a smart knife with proven functionality, robustness or reliability. Originality/value This paper critically reviews and assesses a range of sensing technologies with very specific requirements: to be compatible with robotic assisted cutting in the meat industry. The concept of a smart knife that can benefit from these technologies to provide a real-time “feeling feedback” to the robot is at the centre of the discussion.

Monitoring protein unfolding transitions by NMR-spectroscopy

NMR-spectroscopy has certain unique advantages for recording unfolding transitions of proteins compared e.g. to optical methods. It enables per-residue monitoring and separate detection of the folded and unfolded state as well as possible equilibrium intermediates. This allows a detailed view on the state and cooperativity of folding of the protein of interest and the correct interpretation of subsequent experiments. Here we summarize in detail practical and theoretical aspects of such experiments. Certain pitfalls can be avoided, and meaningful simplification can be made during the analysis. Especially a good understanding of the NMR exchange regime and relaxation properties of the system of interest is beneficial. We show by a global analysis of signals of the folded and unfolded state of GB1 how accurate values of unfolding can be extracted and what limits different NMR detection and unfolding methods. E.g. commonly used exchangeable amides can lead to a systematic under determination of the thermodynamic protein stability. We give several perspectives of how to deal with more complex proteins and how the knowledge about protein stability at residue resolution helps to understand protein properties under crowding conditions, during phase separation and under high pressure.

Melanin diagnostics with nonlinear optics: a mini-review

Optical methods are widely used to perform fundamental studies of living systems and solve problems of biomedical diagnostics. Along with the classical spectroscopy, methods of nonlinear optics (e.g., multiphoton microscopy) are also applied in biophotonics. The potential of nonlinear optical methods for visualisation and analysis of the properties of endogenous chromophore molecules are considered in this minireview. Melanin - a pigment with specific spectral features of photophysical properties in the visible and near-IR ranges - is taken as an example. It is discussed what information about its localisation in tissues and structural organisation can be obtained by nonlinear optical methods: multiphoton fluorescence microscopy (including fluorescence lifetime imaging), third harmonic generation, pump - probe spectroscopy, and coherent anti- Stokes Raman spectroscopy.

Comparison between 3D-reconstruction optical methods applied to bulge-tests through a feed-forward neural network

The mechanical behaviour of rubber-like materials can be investigated through numerous techniques that differ from each other in costs, execution times and parameters described. Bulge test method proved helpful for hyperelastic membranes under plane and equibiaxial stress state. In the present study, bulge tests in force control were carried out on SBR 20% CB-filled specimens. 3D reconstructions of the dome were achieved through two different stereoscopic techniques, the epipolar geometry and the Digital Image Correlation. Through a Feed-Forward Neural Network (FFNN), these reconstructions were compared with the measurements by a laser triangulation sensor taken as reference. 3D-DIC reconstruction was found to be more accurate. Indeed, bias errors of the 3D-DIC and epipolar techniques with respect to the relative reference values, under creep condition, were 0.53 mm and 0.87 mm, respectively.<br /><br />

ANALYSIS OF METHODS FOR STUDYING THE SIZE OF NANOPARTICLES

В представленной работе рассмотрены методы определения размеров наночастиц различными способами. Определен эффективный метод нахождения возможных вариантов. Содержатся сведения о многообразии этих методов и о приёмах их реализации. Выбрана и проанализирована информация по различным методам и исследованиям. Рассмотрены принципиально отличающиеся методы нахождения размеров наночастиц. Одними из перспективных методов являются бесконтактные (оптические). Подвергнуты анализу и приведены диапазоны крупности исследуемых частиц при использовании методов: оптической микроскопии, электронной микроскопии, сканирующей зондовой микроскопии. Описаны принципы работы и возможные схемы установок для изучения исследуемого материала. Более подробно освещен седиментационный метод с применением центрифугирования и рентгеновского принципа детекции. Отмечены его преимущества перед другими методами. Приведены примеры его использования на экспериментальной установке, позволяющей получать дифференциальные и интегральные характеристики в различных базисах, которые позволяют анализировать распределение частиц по крупности при гранулометрическом исследовании материалов, включая наноматериалы. In the presented work, various methods for determining the size of nanoparticles are considered. An effective method for finding possible options has been determined. Information on various methods and studies was selected and analyzed. Fundamentally different methods for finding the sizes of nanoparticles are considered. Non-contact (optical) methods are the most promising. The particle size ranges of the investigated particles are analyzed and presented using the next methods: optical microscopy, electron microscopy, scanning probe microscopy. The principles of operation and possible schemes of installations for studying the material under study are described. The sedimentation method, using centrifugation and the X-ray principle of detection, is described in more detail. Its advantages over other methods are noted. Examples are given of its use in an experimental setup that allows obtaining differential and integral characteristics in various bases, which make it possible to analyze the particle size distribution in the granulometric study of materials, including nanomaterials.