Additional Processing Research Articles

Exploration of surface treatment and liquid additive processing for enhanced multilayer ceramic capacitors performance

This study proposes the development of an optimum multilayer ceramic capacitor (MLCC) that exhibits outstanding performance. Novel research on the improvement of the dispersibility of the dielectric slurry using BaTiO3 is carried out and the results are analyzed and assessed. To improve the dispersibility of the fine powder, various types of silane coupling agents are used to comparatively analyze properties of the dielectric sheet and the MLCC sample chip. In addition, a powder form Dy is generally used to improve the reliability of MLCC dielectric properties; nonetheless, outstanding properties are achieved by applying a liquid form Dy. Therefore, this research combines the optimal surface treatment method of the ferroelectric powder for the manufacture of outstanding MLCCs and the method of treating liquid form additive to achieve innovative research results to obtain MLCCs with outstanding performance.

A sensitive coumarin fluorescence sensor designed for isoprene detection and imaging research in plants

The release of isoprene by plants is considered to be an adaptation to the environment. Herein, a highly selective coumarin fluorescent probe (DMIC) was designed for detecting isoprene. When isoprene came into contact with the maleimide of DMIC, an electrophilic addition process took place. The powerful push-pull effect of DMIC was disrupted. Simultaneously, intramolecular charge transfer was initiated. This enabled DMIC to achieve rapid detection of isoprene within 5 min. Furthermore, excellent linearity was observed in the concentration range of 1–560 ppm (R2 = 0.996). A limit of detection is 1.6 ppm. DMIC was applied to in vitro studies of plant release of liberated isoprene. By monitoring the release of isoprene from different tree species throughout the day, the dynamics of isoprene release from plants throughout the day have been successfully revealed. In addition, the release of isoprene varied considerably among different tree species. In particular, the biocompatibility of DMIC allowed for the in vivo detection of isoprene using fluorescence imaging. The results successfully revealed the dynamics of isoprene release in plants under stress. The amount of isoprene that a plant produced increased with the severity of the stress it experienced. This suggested that the level of isoprene content in plants could be used as a preliminary indicator of the physiological health status of plants. This research demonstrates great potential for clarifying signal transduction in biological systems. It provided ideas for further understanding the biology of isoprene.

Sustainability in Family and Nonfamily Businesses in the Wine Industry

The implementation of environmentally sustainable initiatives within organizations is a shared research topic across both sustainability and family business research. Using a case study approach, this paper provides an in-depth exploration of the presence, role, and strategic nature of environmentally sustainable processes within the Chilean wine industry. Our interview process resulted in 21 interviews between July and November of 2014. Our findings suggest that the recognized tendency of family firms to both engage in and benefit from sustainability practices may not only be owed to their desire to preserve family socio-emotional wealth, but also the unique ability to better incorporate, apply, and effectively benefit from such investments. These findings extend previous work in this area by recognizing additional processes necessary for the development of proactive sustainability practices which are not considered using the motivation-based schema common in extant work. Our findings are analyzed and discussed as they relate to both family business and sustainability research and serve as a bridge between these two related research domains.

MR Elastography: Practical Questions, From the AJR Special Series on Imaging of Fibrosis.

MR elastography (MRE), first described in 1995 and FDA-cleared in 2009, has emerged as an important tool for noninvasively detecting and staging liver fibrosis in patients with known or suspected chronic liver disease. This review focuses on a series of practical questions about the clinical use of MRE. Most head-to-head comparison studies with other laboratory and imaging-based tests have concluded that MRE has the highest diagnostic performance among tests for staging liver fibrosis. Limitations in the accuracy of biopsy as a standard of truth in staging liver fibrosis are increasingly being recognized. MRE-based measurements show promise as quantitative surrogates of disease severity and predictors of important clinical outcomes. The appropriate role of MRE in the management of patients with chronic liver disease is being actively incorporated into recognized clinical guidelines. Growing evidence shows that MRI measurement of elevated liver fat is the most important single biomarker for detecting nonalcoholic steatohepatitis (NASH) and that MRE-based liver stiffness is the most important single biomarker for detecting at-risk NASH (i.e., NASH with stage ≥ F2 fibrosis). Advances in MRE technology are offering higher precision and new biomarkers, which have potential to allow independent assessment of inflammation and other histologic processes in addition to fibrosis.

Enhancing Operations Quality Improvement through Advanced Data Analytics

This study focuses on the application of data analytics algorithms for real-time monitoring in additive manufacturing processes. The utilization of advanced analytics plays a pivotal role in enhancing the quality control and efficiency of these manufacturing techniques. The research explores how data-driven insights can be harnessed to identify, analyze, and rectify deviations in the manufacturing process, ensuring optimal performance and product quality. By integrating sophisticated monitoring algorithms, the study aims to create a robust framework that continuously analyzes various parameters during additive manufacturing. This includes monitoring factors such as temperature, pressure, and material properties in real-time. The collected data is processed through advanced analytics tools to detect anomalies or deviations from the expected standards. The implementation of machine learning algorithms further facilitates predictive maintenance and proactive adjustments, contributing to the overall reliability and effectiveness of additive manufacturing processes. The outcomes of this research hold significant implications for industries relying on additive manufacturing technologies, providing a foundation for improved process control and product quality. The study contributes to the growing field of Industry 4.0 by showcasing the integration of data analytics as a key enabler for efficient and reliable additive manufacturing.

Hybrid directed energy deposition process coupled with plastic deformation

Laser directed energy deposition (LDED) process has unique advantage in rapid forming of large-sized metal components, gradient material/structural components, or repairing/remanufacturing worn parts. However, the high residual stress and strong anisotropy in mechanical properties of the as-deposit components limit the application of LDED technology in the manufacturing of key structural components. To overcome these problems, various hybrid additive manufacturing (HAM) technologies have been developed, such as plastic deformation, ultrasonic or magnetic field assisted LDED processes to improve the quality and the mechanical properties, where these coupled processes are carried out either simultaneously or cyclically with the LDED process. The hybrid additive manufacturing, while retaining the advantages of individual forming process, avoids the mutual interference between each process and reducing the adverse effects generated if used separately. Hybrid additive manufacturing processes fundamentally change the underlying physical mechanisms of molten pool dynamics, microstructural evolution, temperature and thermal stress gradient in additive manufacturing, thereby optimizing the microstructure and performance of the manufactured components. In this paper, the key technical features of the hybrid additive manufacturing process coupled with plastic deformation were described in details, and the resulting differences in microstructure, residual stress, and mechanical properties of the prepared samples were systematically analyzed. The developing trend of hybrid additive manufacturing processes in coupling mechanisms, parameter optimization, and equipment have been discussed.

The influence of layer height in the orthotropic elastic properties of PLA material obtained by additive processes

Polylactic acid (PLA) is a biodegradable thermoplastic polyester used extensively in 3D printing, that can be obtained from renewable resources with low production costs and low carbon emissions. The extrusion temperature of PLA is lower, and its tensile strength and elastic modulus are higher than that of other common polymeric thermoplastic materials.To assess the structural integrity of parts obtained by additive manufacturing, especially in more complex geometries, the finite element method is extensively used, being necessary, for this purpose, to characterize the constitutive model of the material. From the printer manufacturing parameters, one of the most affecting the elastic and strength properties is the layer height.The layer-by-layer slicing sequence of additive manufacturing processes can introduce anisotropy into the materials, whereby, in most applications, materials obtained by these processes are considered orthotropic. The mechanical characterization of anisotropic materials through classical tests is not always the most suitable for this purpose, given the economic aspects, the time required, precision requirements and, sometimes, the technological difficulties of the tests. The ASTM E1876-21 standard presents a method for determining the dynamic elastic properties of materials by impulse excitation of vibration, at room temperature.In this article, the influence of the layer height in the dynamic Young's Modulus, Shear Modulus, and Poisson's Ratio obtained by impulse excitation of vibration (ASTM E1876-21 standard), of Tough PLA is analyzed.

Safety evaluation of an extension of use of the food enzyme containing cellulase, endo-1,3(4)-β-glucanase and endo-1,4-β-xylanase from the non-genetically modified Trichoderma reesei strain AR-256.

The food enzyme containing cellulase (EC 3.2.1.4), endo-1,3(4)-β-glucanase (EC 3.2.1.6) and endo-1,4-β-xylanase (EC 3.2.1.8) is produced with the non-genetically modified Trichoderma reesei strain AR-256 by AB-Enzymes GmbH. A safety evaluation of this food enzyme was made previously, in which EFSA concluded that this food enzyme did not give rise to safety concerns when used in seven food manufacturing processes. Subsequently, the applicant requested to extend its use to include two additional processes. In this assessment, EFSA updated the safety evaluation of this food enzyme when used in a total of nine food manufacturing processes: processing of cereals and other grains for the production of 1) baked products, 2) cereal-based products other than baked, 3) brewed products, 4) starch and gluten fractions, 5) distilled alcohol; processing of fruits and vegetables for the production of 6) wine and wine vinegar, 7) juices, 8) fruit and vegetable products other than juices and 9) fruit-derived distilled alcoholic beverages other than from grape. As the food enzyme-total organic solids (TOS) is removed from or not carried into the final foods in three food manufacturing processes, the dietary exposure to the food enzyme-TOS was estimated only for the remaining six processes. It was up to 4.049 mg TOS/kg body weight (bw) per day in European populations. Using the no observed adverse effect level (NOAEL) reported in the previous opinion (939 mg TOS/kg bw per day), the Panel derived a revised margin of exposure of at least 232. Based on the revised exposure calculation and the outcome of the previous evaluation, the Panel concluded that this food enzyme does not give rise to safety concerns under the revised intended conditions of use.

Extractability of oleuropein, hydroxytyrosol, tyrosol, verbascoside and flavonoid-derivatives from olive leaves using ohmic heating (a green process for value addition)

This figure highlights the effectiveness of ohmic heating (considering extraction temperature and solvent ratio) compared to conventional heating in the recovery of representative polar phenols of olive leaves.

Investigation of comfort characteristics of knitted fabric produced from neppy yarn

Fabric made from fancy yarn, especially neppy yarn has a great environmental impact because the fabric does not need any additional dyeing process. This study involved knitting neppy yarn of two distinct spinning processes, vortex and ring spinning, each having three different percentages of neps. The comfort properties of six different fabrics were evaluated by analyzing various parameters, including moisture management properties, water vapor transmission rate, air permeability, hand feel properties, and bursting strength. Microscopic views were also examined for analyzing the physical appearance of the fabric’s surface. The experimental results revealed that fabrics made from vortex-spun neppy yarn (VSNY) exhibit better moisture management, breathability, and hand feel properties than ring-spun neppy yarn (RSNY). Alternatively, bursting strength and water vapor evaporation rate showed a lower trend in fabrics made from vortex-spun neppy yarn. The research findings contribute valuable insights into the potential of vortex spinning techniques for sustainable and comfortable textile production.

An apparatus to study arc-wire direct energy metal deposition additive manufacturing process in a drop tower microgravity platform.

Understanding the mechanisms and dynamics of molten metal droplet transfer within the plasma of a directed energy deposition arc process in microgravity is critical for optimizing the build process with minimal defects. This paper presents a unique experimental setup designed to investigate the transfer of molten metal droplets in the microgravity environment of a drop tower. The primary design of the apparatus revolves around accommodating, within the confines of the drop tower experimental capsule, essential components, including a high-speed camera with necessary filters for capturing molten metal droplets, a consumable electrode wire-arc setup, batteries, a linear traverse stage for single bead deposition, sensors, data acquisition systems, online communication systems, and the control system. These systems are secured to withstand the high deceleration forces at the end of a free fall in the drop tower. The arrangement has demonstrated consistent deposition outcomes, capturing clear images of droplet transfers using a high-speed camera along with voltage, current, and temperature data during the microgravity state induced by free fall. This apparatus will serve as a foundational element in establishing a viable additive manufacturing capability for space applications, as it provides fundamental insights into the transfer of molten metal droplets.

Avaliação da Influência dos Parâmetros de Processamento na Manufatura Aditiva do Aço VP50IM por PCGTAW

Abstract The wire arc additive manufacturing process or WAAM (Wire Additive Arc Welding) is recognized as a process able of making pieces of high geometric complexity, with mechanical properties comparable to those of the cast material. However, there are significant challenges associated with WAAM, such as undesirable microstructures and mechanical properties, high residual stresses and geometric distortion. This study aims to contribute to the selection of deposition parameters for VP50IM steel using WAAM via pulsed TIG (Tungsten Inert Gas) and characterization of the generated stacking, using the Central Composite Complete methodology, CCC. In this study, the peak (Cp) and base (Cb) current, wire feed speed during peak (Vap), base (Vab) and welding speed (Vs) were varied. The ideal parameter presented was Cp=200A, Cb=100A, Vap=2.9cm/min, Vab=1.2cm/min and Vs=20cm/min. Tensile tests showed up to 15% greater resistance in the samples in the longitudinal section in the welding direction compared to the transverse direction. Hardness tests demonstrated up to 9% less hardness at the center of the stack compared to the top and bottom. The fracture analysis of the specimens showed ductile fracture.

Single Millisecond Pulsars from Dynamical Interaction Processes in Dense Star Clusters

Globular clusters (GCs) are particularly efficient at forming millisecond pulsars. Among these pulsars, about half lack a companion star, a significantly higher fraction than in the Galactic field. This fraction increases further in some of the densest GCs, especially those that have undergone core collapse, suggesting that dynamical interaction processes play a key role. For the first time, we create N-body models that reproduce the ratio of single-to-binary pulsars in Milky Way–like GCs. We focus especially on NGC 6752, a typical core-collapsed cluster with many observed millisecond pulsars. Previous studies suggested that an increased rate of neutron star binary disruption in the densest clusters could explain the overabundance of single pulsars in these systems. Here, we demonstrate that binary disruption is ineffective and instead we propose that two additional dynamical processes play dominant roles: (1) tidal disruption of main-sequence stars by neutron stars and (2) gravitational collapse of heavy white dwarf binary merger remnants. Neutron stars formed through these processes may also be associated with fast radio bursts similar to those observed recently in an extragalactic GC.

Lightweighting structures using an explicit microarchitectured material framework

In this paper, a new approach to design ultralight structures is developed based on a previous work called Efficient Multiscale Topology Optimization. A parameterized (or explicit) truss-based cell is introduced to generate intrinsically well-connected microstructures and to get clear interpretable optimal multiscale structures. The method uses a pre-computed database of optimal micro-cells to be computational efficient without losing in structural performances. The parameterization allows to generate a lightweight database just storing the set of parameters, that define the optimal cells, and the cells properties, that are obtained through inverse homogenization. The method has been successfully tested on two-dimensional compliance problems. Several examples demonstrate its versatility and give quantitative results. Moreover, it allows to obtain structures compatible with additive manufacturing processes, to naturally solve concurrent multi-scale problems, as well as controlled porosity and optimal fiber orientation problems.

Smart‐Alloying – Liquid in-situ re-alloying in additive manufacturing

Smart-Alloying enables local modification of the chemical composition of metallic components within additive manufacturing processes. In the example of laser based powder bed fusion (PBF-LB/M), this new technology uses suspensions to place alloying elements precisely at every requested point of the printed area. It allows a tailor-made change of the local microstructure and properties. High chromium-containing stainless steel and carbon as the alloying element serves as a demonstration example. Microprobe and EBSD analyses confirm a locally increasing carbon content, which leads to the formation of fine martensitic structures with chromium-rich carbides at the grain boundaries of the ferritic base material. The associated change in microstructure regarding grain size and phase composition results in modified mechanical properties. Indentation tests carried out show a corresponding locally increased indentation hardness. This decisive influence of even individual alloying elements paves a new way for functional grading of metallic components in additive manufacturing.

Development of a selective and scalable N1-indazole alkylation.

N1-Alkyl indazoles are a ubiquitous and privileged motif within medicinal chemistry, yet methods to selectively furnish N1-alkyl indazoles with simple alkyl side chains remain sparse. Herein, negative data from high-throughput experimentation (HTE) enabled a confident pivot of resource from continued optimisation to the development of an alternative reaction. This workflow culminated in a methodology for the synthesis of N1-alkyl indazoles. The procedure is highly selective for N1-alkylation, practical, and broad in scope, with no N2-alkyl products detected at completion. Mechanistic understandings were consistent with attributing the high selectivity to thermodynamic control. Additional data-driven process development led to this reaction being safely demonstrated on a 100 g scale, with potential for further scale up. This study highlights pragmatic principles followed to develop a necessitated methodology, suitable for large scale manufacture.

Strong green upconversion emission from submicron spindle-shaped SrMoO4:Yb3+,Er3.

Upconversion luminescence (UCL) is a fluorescence process where two or more lower-energy photons convert into a higher-energy photon. Lanthanide (Ln3+)-doped UCL materials often suffer from weak luminescence, especially when directly synthesized by a hydrothermal (HT) process due to the existing hydroxyl group and undesirable arrangement of dopants within host lattices which quench luminescence and limit energy transfer. Therefore, additional heat treatment processes are required to enhance their UCL emission, even though direct hydrothermal synthesis without further heat treatment has the advantages of low energy consumption, fast synthesis, and wide applicability to generate UCL materials. In this study, via a HT process without annealing, we have produced Yb3+ and Er3+ co-doped SrMoO4 submicron spindles with a strong green UCL emission which can be seen with the naked eye, which HT produced oxide-based UCL materials often fail to demonstrate. We have investigated different HT synthesis conditions, such as temperature, time, pH and dopant composition, which control the nucleation, growth, lattice structure arrangement, and ultimately their UCL properties through XRD, SEM, EDS and UCL measurements. The bright green UCL from the SrMoO4:Yb,Er submicron spindles is further enhanced by post-synthesis annealing within a molten NaNO3/KNO3 system to prevent particle size growth. The green UCL intensity from the annealed SrMoO4:Yb,Er submicron spindles surpasses samples produced by the solid-state method and is comparable to that from the commercial NaYF4:Yb,Er sample. We have further studied the temperature-dependent luminescence of both the HT-prepared and molten-salt annealed SrMoO4:Yb,Er submicron spindle samples. The strong UCL from our SrMoO4:Yb,Er submicron spindles could warrant their candidacy for bioimaging and anticounterfeiting applications.

Angular momentum transport near convective-core boundaries of Gamma Doradus stars

Recent asteroseismic studies have revealed that the convective core ofγDoradus stars rotates faster than their radiative interior. We study the development of differential rotation near the convective core to test angular momentum transport processes that are typically adopted in stellar evolution models. Models that only include the advection of angular momentum by meridional circulation and shear instabilities cannot reproduce current rotational constraints, irrespective of the initial conditions. The latest formulation of internal magnetic fields based on the Tayler instability is indeed able to reproduce the internal rotation rate of post-main sequence stars; however, it appears too efficient during the main sequence and has thus been disfavoured. A less efficient version of the same transport process can simultaneously reproduce the rotation rate of the convective core, the rotation rate in radiative regions as probed by gravity-modes, and the surface rotational velocities ofγDoradus stars. Our work suggests that there are additional physical processes apart from internal magnetic fields at work in the stellar interiors of post-main sequence stars.

Spectral analysis of cross-hole sonic logging data for pile integrity assessment

Ensuring the safety of foundations requires advanced non-destructive testing techniques. Cross-hole sonic logging (CSL) is a widely adopted method for evaluating the integrity of deep foundation elements, such as bored piles, barrettes, and diaphragm walls. This method involves analyzing the propagation time and relative energy of ultrasonic pulses transmitted and registered by probes inserted into pre-installed access tubes. However, in certain cases, standard analyses may not effectively distinguish anomalous signals arising from defects and other factors unrelated to concrete quality. Our study explores the potential of an alternative frequency-domain approach for CSL data analysis. We propose new attributes to quantify ultrasonic signal spectra, including spectrum area, normalized spectrum area, weighted mean frequency, and maximum frequency. These attributes are automatically calculated, eliminating the need for additional data processing time and minimizing the risk of human error. The proposed approach was applied to CSL data collected from two bored piles of 46 m length and successfully identified signals classified as anomalous through standard time-domain analysis. Further research is deemed necessary to fully explore the potential of the frequency-domain approach in enhancing the information content and reliability of CSL pile integrity testing

Exploring the impact of design tool usage on design for additive manufacturing processes and outcomes

Abstract Improving designers’ ability to identify manufacturing constraints during design can help reduce the time and cost involved in the development of new products. Different design for additive manufacturing (DfAM) tools exist, but the design outcomes produced using such tools are often evaluated without comparison to existing tools. This study addresses the research gap by directly comparing design performance using two design support tools: a worksheet listing DfAM principles and a manufacturability analysis software tool that analyzes compliance with the same principles. In a randomized-controlled study, 49 nonexpert designers completed a design task to improve the manufacturability of a 3D-printed part using either the software tool or the worksheet tool. In this study, design outcome data (creativity and manufacturability) and design process data (task load and time taken) were measured. We identified statistically significant differences in the number of manufacturability violations in the software and worksheet groups and the creativity of the designs with novel build orientations. Results demonstrated limitations associated with lists of principles and highlighted the potential of software in promoting creativity by encouraging the exploration of alternative build orientations. This study provides support for using software to help designers, particularly nonexpert designers who rely on trial and error during design, evaluate the manufacturability of their designs more effectively, thereby promoting concurrent engineering design practices.