Processing Temperature Research Articles

Effect of Hydrogen Sulfide Concentration on Two-Dimensional SnS2 Film by Atomic Layer Deposition in Annealing process.

Two-dimensional (2D) materials are widely studied due to their unique physical, optical, electrical properties and good compatibility with various synthesis methods. Tin disulfide (SnS2) has high uniformity and conformality even at low process temperatures and is a two-dimensional material with accurate thickness control using atomic layer deposition (ALD). However, since the crystallinity of thin film is low at a low process temperature, various post-annealing methods are being studied to compensate for film quality. In this work, we compared the crystal structures, chemical binding energies, and electrical properties of post-annealed SnS2 thin films at hydrogen sulfide concentrations of 4.00 % and 99.99 %. The crystallinity, grain size, and carrier concentrations of the SnS2 thin film were highest at a post-annealing temperature of 350 ℃ and a hydrogen sulfide concentration of 99.99 %, and the chemical binding energies corresponded with the standard Sn4+ states, forming a pure 2D-hexagonal SnS2 phase. In addition, SnS2 thin films deposited via ALD showed high uniformity and conformality in large-scale wafers and trench structure wafers.

Shaping the Future of Functional Foods: Using 3D Printing for the Encapsulation and Development of New Probiotic Foods.

Consumers have been demanding foods that, besides providing nutrition, bring some health benefits, known as functional foods. The insertion of probiotics in foods is a strategy for developing functional foods. Still, it has been a challenge because these matrices have different pHs and undergo different process temperatures and times that can reduce the viability of these microorganisms. In this sense, encapsulation using 3D printing emerges to protect probiotic microorganisms and ensure that they reach the intestine viable and carry out the expected beneficial action. Thus, this review evaluates the current advancements in 3D printing to encapsulate and develop novel probiotic foods. Research has shown that 3D printing effectively encapsulates probiotic microorganisms, preserving their viability throughout the gastrointestinal tract. Studies have proven the effectiveness of 3D printing encapsulation in protecting probiotics during processing, storage, and digestion. Innovative formulations for 3D bioprinted products with probiotics, such as food structures based on cereals, mashed potatoes, and cream, have been developed. Producing products with shelf life and combining applications of phytochemicals and probiotics aims to improve personalized nutrition, textural characteristics, and sensory attributes of the foods produced by this emerging approach. Therefore, 3D printing of foods with probiotics has the potential to create new products that meet this demand.

Green strategies for the valorization of industrial medicinal residues of Serenoa repens small (saw palmetto) as source of bioactive compounds

Serenoa repens is a medicinal plant well-known for its therapeutic potential in treating various urological disorders and prevention of prostatic cancer. However, the extraction process in the pharmaceutical industry leads to the generation of plant residues, typically discarded, wasting valuable resources. In this study, we aimed to explore a series of green extraction strategies to effectively valorize the residues of Serenoa repens fruits. Initially, we employed supercritical CO2 (1.2% yield on dry biomass) on the discarded biomass to identify and quantify residual fatty acids and polyprenols (1.6% of the extract dry weight), a class of unsaturated isoprenoid alcohols with promising biomedical applications. Subsequently, subcritical water extraction was utilized on the exhausted biomass to extract polar compounds. An increase in the extraction yield was observed with the rise in processing temperature up to 180 °C (yields were found higher than 26%). Phenolic compounds and carbohydrate macromolecules profiles were affected by the increased hydrolytic conditions. Polar extracts exhibited robust bioactivities, demonstrating significant antioxidant activity and antimicrobial efficacy against Gram-positive and Gram-negative bacteria strains. Extracts obtained at 180 °C demonstrated the highest efficacy. Furthermore, in vitro assessment of mannans-rich fraction provided a new perspective of potential applications in the cosmeceuticals field. Results underscore the potential of the sustainable extraction biorefinery for the residue of this medicinal plant and demonstrate that, harnessing these bioactive compounds, new sustainable and eco-friendly approaches for its complete utilization can be offered, thereby promoting near-zero waste practices and contributing to a more sustainable future.

Optimisation of interlayer temperature in wire-arc additive manufacturing process using NURBS-based metamodel

Optimisation of interlayer temperature in wire-arc additive manufacturing process using NURBS-based metamodel

Synthesis of mesoporous cobalt-doped MoO3 nanoribbons for highly selective detection of triethylamine

Co-doped MoO3 nanobelts are successfully synthesized as model materials by MOF derivatization method, and the gas sensing performance towards TEA as well as the sensing mechanism are studied. In particular, the MCo-MoO3-450 sample exhibits the best TEA sensing performance at 110 °C, with superior anti-interference ability and high sensing response (Ra/Rg = 361.62, 50 ppm). It is noteworthy that the improvement of TEA sensing performance can be achieved by adjusting the processing temperature to control the Co2+/Co3+ ratio. This work offers a dependable approach for the production of cobalt-doped MoO3 nanobelts and demonstrates that cobalt doping is a viable tactic for designation of high-performance TEA sensors.

Thermal decomposition temperature-dependent bonding performance of Ag nanostructures derived from metal–organic decomposition

AbstractIn wide-bandgap semiconductor power device packaging, die bonding refers to attaching the die to substrate. Thereby, the process temperature of Ag sintering for the die bonding should be low to prevent damage to fragile dies. Herein, an organic-free strategy using Ag nanostructures derived from the thermal decomposition of metal–organic decomposition (MOD) was proposed to achieve low-temperature bonding. Significant effects on bonding performance were determined by the thermal decomposition temperature, which in turn determined the organic content and sintering degree of Ag nanostructures. At a low thermal decomposition temperature of 160 °C, incomplete decomposition resulted in high organic content in the Ag nanostructures, causing large pores inside the Ag joints owing to the generation of gaseous products. Owing to the Ag particles with naked surfaces and wide size distribution, the Ag nanostructure obtained at 180 °C showed an excellent bonding performance, resulting in a high shear strength of 31.1 MPa at a low bonding temperature of 160 °C. As the thermal decomposition temperature was 200 °C, sintering among Ag particles increased the particle size, resulting in a reduction of surface energy and driving force for sintering. We think that uncovering this underlying mechanism responsible for the bonding performance will promote the application of Ag MOD in the die bonding of WBG power devices. Graphical abstract

Направления совершенствования сероочистки, осушки и переработки природного газа

The results of the work of the staff of the Department of “Chemical Technology of Oil and Gas Refining” of Astrakhan State Technical University in the field of separation of three-phase reservoir mixture, increasing the efficiency of desulfurization, improving the process of drying gas and the production of continuous hydrocarbons – raw materials for petrochemistry. The influence of the quality of raw materials entering processing on the formation of deposits in technological equipment has been studied. Reconstruction of the inlet and three-phase separators of high-pressure reservoir mixture separation plants by installing a vibration damper and a depulsor on the reservoir mixture supply line to the installation, as well as reconstruction of the input of raw materials into the separator of the installation. The use of the KPG-200 defoamer and the KPG-200 AV antifoamer made it possible to reduce the consumption rate of defoaming reagents several times in gas purification plants from acidic components. The influence of various impurities on the foaming of working amine solutions (mechanical impurities, coal dust, products of thermal destruction of amine, thermostable salts, corrosion inhibitors) has been determined. It was revealed that the products of thermal degradation of amine have the greatest effect at concentrations above 3% by weight. A method for reducing the content of mechanical impurities in a solution of diethanolamine in a constant magnetic field has been developed and introduced into an industrial desulfurization plant. The filtration efficiency increases 2.6 times, the foam height is halved, and the foam stability is quadrupled. At the same time, the activity of the defoamer increases by 1.7 times. The mathematical dependence of the height of the protective layer of aluminum oxide in an adsorber with zeolite on impurities of diethanolamine has been experimentally found. The effectiveness of the developed improved distribution ring device is shown, the use of which makes it possible to practically eliminate dead zones in the zeolite layer and thereby increase the efficiency of the adsorption process and increase the inter-regeneration period on the drying unit. Studies of the catalytic pyrolysis of the butane fraction using CVM-type pentasils modified with the introduction of chromium can reduce the process temperature compared with the thermal decomposition of raw materials by more than one hundred degrees 100 °C.

Photo‐Curable Fluorinated High‐k Polyimide Dielectrics by Polar Side Substitution Effect for Low‐Voltage Operating Flexible Printed Electronics

AbstractPolyimide‐based dielectric films are widely used in various thin film devices including organic field‐effect transistors (OFETs) owing to their promising thermal/chemical stability, mechanical flexibility, and insulating properties. On the other hand, considerable attention is paid to lowering the process temperature to allow coating on plastic substrates because high‐temperature annealing (≈200 °C) is usually required to convert precursors to polyimide films with those excellent properties. In addition, polyimide‐based dielectric films have low dielectric constants (k) (<4). Therefore, modifying the k properties of polyimide is a critical issue for applications as an insulating thin film for practical transistors. This paper reports a new type of polyimide‐based gate dielectric comprising methacryloyl moiety (PI‐MA) as a side chain for photo‐pattern/processability and high‐k properties. This study shows that the photocured PI‐MA thin films show excellent insulating properties (leakage current densities < 10−8 A cm⁻2 at 4 MV cm⁻1) and high‐k properties (≈8) even without a post‐annealing process. Finally, the use of PI‐MA in printed field‐effect transistors results in high performance with low‐voltage operation (within 5 V) and integrated logic‐gate devices (NOT, NAND, and NOR gates).

Elemental diffusion coefficient prediction in conventional alloys using machine learning

This paper presents the Machine Learned Diffusion Coefficient Estimator, a comprehensive machine learning framework designed to predict diffusion coefficients in impure metallic (IM) and multi-component alloy (MCA) media. The framework incorporates five machine learning models, each tailored to specific diffusion modes: (1) impurity and (2) self-diffusion in IM media, and (3) self, (4) impurity, and (5) chemical diffusion in MCA media. These models use statistical aggregations of atomic descriptors for both the diffusing elements and the diffusion media, along with the temperature of the diffusion process, as features. Models are trained using the random forest and deep neural network algorithms, with performance evaluated through the coefficient of determination (R2), mean squared error (MSE), and uncertainty estimates. The models within this framework achieve an impressive R2 score above 0.90 with MSE less than 10−16 m2/s, demonstrating high predictive accuracy and reliability for diffusion coefficient.

Impact of Bias Stress and Endurance Switching on Electrical Characteristics of Polycrystalline ZnO-TFTs with Al2O3 Gate Dielectric

Abstract This study experimentally investigates electrical characteristics and degradation phenomena in polycrystalline zinc oxide thin-film transistors (ZnO-TFTs). ZnO-TFTs with Al2O3 gate dielectric, Al-doped ZnO (AZO) source-drain contacts, and AZO gate electrode are fabricated using remote plasma-enhanced atomic layer deposition (PE-ALD) at a maximum process temperature of 190°C. We employ positive bias stress (PBS), negative bias stress (NBS), and endurance cycling measurements to evaluate the ZnO-TFT performance and examine carrier dynamics at the channel-dielectric interface and at grain boundaries in the polycrystalline channel. DC transfer measurements yield a threshold voltage of −5.95 V, a field-effect mobility of 53.5 cm2/(V∙s), a subthreshold swing of 136 mV/dec, and an on-/off-current ratio above 109. PBS and NBS measurements, analysed using stretched-exponential fitting, reveal the dynamics of carrier trapping and de-trapping between the channel layer and the gate insulator. Carrier de-trapping time is 88 s under NBS at −15 V, compared to 1856 s trapping time under PBS at +15 V. Endurance tests across 109 cycles assess switching characteristics and temporal changes in ZnO-TFTs, focusing on threshold voltage and field-effect mobility. The threshold voltage shift observed during endurance cycling is similar to that of NBS due to the contrast in carrier trapping/de-trapping time. A measured mobility hysteresis of 19% between the forward and reverse measurement directions suggests grain boundary effects mediated by the applied gate bias. These findings underscore the electrical resilience of polycrystalline ZnO-TFTs and the aptitude for 3D heterogeneous integration applications.

Evaluation of Processing Parameters in the Solvothermal Synthesis of Cu-Rich Tetrahedrites for Potential Application as Thermoelectric Materials

The major issue associated with thermoelectric performance is the low efficiency of power conversion. The main challenge is achieving a combination of high Seebeck coefficient, high electrical conductivity, and low thermal conductivity for a significantly improved figure of merit (ZT). Developing strategies include the production of tetrahedrites with an intrinsically low thermal conductivity through the solvothermal method, using a low reaction time and processing temperature. Here, we report on the preparation of Cu-rich tetrahedrites through the solvothermal technique at low temperature, providing a promising strategy for the preparation of materials with potential applications in thermoelectricity. The influence of synthesis reaction time and temperature on the morphological, structural, and thermoelectrical properties of the samples was investigated through different characterization techniques. Tetrahedrite synthesized at 180 °C for 19 h yielded a favorable ZT value of >0.43 and a thermal conductivity of 0.2 Wm−1 K−1 (423 K), related to the Sb3+/Sb5+ and Cu+/Cu2+ ratio, as was observed by XPS. The cubic tetrahedrite phase attributed to the (222) plane was confirmed by XRD and TEM and the intense Raman mode observed at 351 cm−1. SEM images revealed that nanotetrahedral Cu-rich tetrahedrites efficiently assemble into spherical structures, resulting in an improvement in the Seebeck coefficient (437 µVK−1) and electrical conductivity.

Effect of maltodextrin concentration and temperature process on physicochemical characteristics of instant lemon (Citrus limon l) powder minute using crystallization machine

The purpose of this study was to determine the effect of maltodextrin concentration and drying temperature on the physicochemical characteristics of instant lemon powder drinks. The research used the randomized design group with a 3x3 factorial pattern consisting of two factors with two repeats so that 18 experimental units were obtained. There is a T factor which is a concentration of maltodextrin consisting of three levels, namely t1 (10%), t2 (15%), and t3 (20%), and a K factor that is a variation of the process temperature also consisting of three levels, namely k1 (50°C), k2 (60°C), and k3 (70°C). In this study, physical responses include solubility, dissolving time, amount of yield, hygroscopicity, bulk density, and scanning electron microscopy. Chemical responses correspond to water content, antioxidant activity, pH value, and vitamin C. The results showed that maltodextrin concentration can affect solubility, dissolving time, amount of yield, hygroscopicity, bulk density, water content, pH value, and vitamin C. Variations in process temperature affect solubility, dissolving time, amount of yield, hygroscopicity, bulk density, moisture content, pH value, and vitamin C. The interaction of maltodextrin concentration and process temperature variations affects hygroscopicity but not solubility response, dissolving time, yield amount, bulk density, water content, pH value, and vitamin C.

Considerations for the safe handling and processing of unstable materials

AbstractWe evaluate the instability hazards of initiators, monomers, and other unstable materials during storage and handling in individual containers, pallets of containers, and storage and process vessels. We propose a simplistic model to analyze the temperature–time profile of an unstable chemical, given heat transfer from/to the environment, heat generation due to decomposition and other reaction kinetics, and heat generated from auxiliary equipment (e.g., agitators/mixers, pumps, vessel jackets). Lumped capacitance‐based heat transfer and decomposition kinetics are integrated to predict self‐accelerating decomposition temperature (SADT), self‐accelerating polymerization temperature (SAPT), and the temperature profile given exposure conditions (e.g., ambient temperature and additional sources of heat). Case studies related to the storage and processing of unstable liquid monomers (i.e., methyl methacrylate, MMA), and organic peroxides, (i.e., tert‐butyl peroxybenzoate, TBPB), are presented. We also provide recommendations on determining safe storage and processing temperatures and steps to prevent emergency situations and include an overview of thermal analysis and data treatment procedures which might affect chemical process safety recommendations.

Thermal modification’s influence on the color of Tectona grandis L.f. sapwood to resemble heartwood

The commercial value of teak wood is associated with its heartwood, which has a naturally darker color than sapwood. To reduce this color disparity, thermal modification can be used to homogenize the color between sapwood and heartwood by minimizing color differences. This research aimed to assess the effectiveness of thermal modification in making the color of teak sapwood similar to that of heartwood. Thermal modification was carried out at 160, 180, 200, and 220 °C for 150 min. Thermal modification of teak sapwood at 180 °C ensured greater color similarity to the heartwood of a fast-growing 16-year-old plantation. The material darkened with increasing process temperature. There was a change in the content of soluble substances, and hot water extraction had greater correlations with hue angle, lightness, and yellowness. Thermal modification also reduced the number of hydroxyl groups and improved the wood’s thermal stability.

Sustainable Polyamide Composites Reinforced with Nanocellulose via Melt Mixing Process

Introduction of biomass-based nanofillers into the polyamide matrix may represent a sustainable approach for the development of high-performance engineering plastics. From this standpoint, nanocellulose, derived from various cellulosic sources, has attracted a great deal of attention because of is exceptional mechanical properties, lightweight nature, and biodegradability, which presents significant advantages over conventional inorganic fillers. However, a technical challenge arises in the industrially favorable melt processing of polyamides and nanocellulose. This challenge is associated with the thermal degradation of nanocellulose at high processing temperatures, as well as the strong tendency of nanocellulose to aggregate within the polymer matrix. This review examines recent developments to address these issues. Key approaches based on the surface treatment of nanocellulose as well as optimization of processing conditions are discussed in detail, which can provide insights on the development of nanocellulose-reinforced polyamide composites.

The Influence of Temperature in the Wire Drawing Process on the Wear of Drawing Dies

The Influence of Temperature in the Wire Drawing Process on the Wear of Drawing Dies

No-impact trajectory design and fabrication of surface structured CBN grinding wheel by laser cladding remelting method

The structured grinding wheels have a specially designed macro or microstructure on the surface, with a relatively low average grinding force and temperature in the cutting zone and more space for chips and coolant. Most traditional grinding wheel fabrication methods, such as electroplating, sintering, and brazing, have the problems of poor abrasive grain holding strength, random abrasive distribution, or thermal deformation of the substrate. To address this, laser cladding remelting technology is introduced to fabricate the structured CBN grinding wheel. A no-impact trajectory was designed on the substrate of the grinding wheel, which can reduce the fluid friction in the channel and increase the fluid pressure at the outlet. The temperature and velocity fields of the grinding process were simulated to verify the feasibility of the designed structure theoretically. The optimal process parameters for the bonding among the metal bond, the abrasive grains, and the substrate were determined by orthogonal and full-scale factorial experiments. The chemical metallurgical reactions between CBN grain and metal bond, as well as between the metal bond and substrate, were formed, increasing the holding force of CBN grains. The method can realize the fabrication of high-strength and long-life structured grinding wheels with an orderly arrangement of abrasive grains. The micro-mechanism of fabrication was analyzed using element distribution measurement and XRD analysis.

Recent Developments in Low Temperature Wafer Level Metal Bonding for Heterogenous Integration

Abstract An overview of various low-temperature (<200°C) wafer bonding processes using metal interlayers is presented. Such processes are very attractive for novel applications in 3D heterogenous packaging as the allow for simultaneous formation of electrical interconnects, as well as hermetic encapsulation of various sensors and microelectromechanical systems-based devices. Metal wafer bonding is a generic category of processes consisting of various sub-categories, each one defined by the different principles governing the process. One can differentiate between eutectic wafer bonding (a eutectic alloy is formed as bonding layer during the process by liquid-solid interdiffusion), intermetallic wafer bonding (an intermetallic alloy is formed as bonding layer during the process by solid-liquid interdiffusion, a process known also as solid liquid intermetallic diffusion transient liquid phase, and metal thermo-compression wafer bonding. Different critical/gating parameters were investigated and their impact for generally reducing processing temperatures for the different metal bonding systems was studied.

Preparation of novel and efficient arylphosphonate flame retardants for simultaneously enhancement of fire safety and UV-shielding properties of transparent thermoplastic polyurethane

Thermoplastic polyurethane (TPU) is highly flammable and UV aging, limiting its application in the field of new energy and electronic device. In this work, a novel macromolecular aromatic phosphonate Bis(4-(((diphenylphosphinyl)oxy)methyl)phenyl)phenylphosphonate (DMP) containing both P-C and P=O was successfully prepared by nucleophilic substitution reaction. The DMP was introduced into the TPU matrix to prepare multifunctional TPU composites. Condensed and gas phase analysis have shown that the flame retardant mechanism of DMP was mainly influenced by flame retardant inhibition and the barrier effect of char layer. Only 5 wt% DMP enabled TPU to obtain the UL-94V-0 rating with the LOI of 27.6 %. Compared with pure TPU, the HRR and THR of TPU/5 wt% DMP were decreased by 19.8 % and 13.2 %. Meanwhile, the matching of the melting point for DMP and the processing temperature for TPU increased its dispersion in TPU matrix. Due to the excellent compatibility between DMP and TPU, TPU/DMP composites almost retained their original transparency and ductility. In addition, TPU/DMP composites exhibited excellent UV resistance, obtaining 100 % UV shielding at UV-B wavelengths and up to 97 % UV isolation at UV-A wavelengths. The study introduced a novel approach for preparing multifunctional flame retardant additives, and opened up wide application prospects for high-performance flame retardant TPU composites in emerging fields such as rail transit and electronic packaging.

Printed Interconnects for Heterogeneous Systems Integration on Flexible Substrates

AbstractHeterogeneous integration on flexible substrates has been explored in recent years to meet the high‐performance and flexible form factors requirements of several emerging applications. Reliable interconnects, in both 2D and 3D layouts, are critical for the effective use of these systems. But it is challenging to employ conventional bonding and interconnect technology due to considerable mismatches in mechanical and thermal properties. For example, the ultra‐thin chips (UTCs) are too fragile to withstand the static or oscillating forces applied during conventional bonding. In this regard, printing of metal tracks on flexible substrates is a promising alternative to access the contact pads on integrated circuits (ICs), as the interconnects on diverse substrates can be realized at room temperature processing using as much materials as needed. Further, it is easier to attain step coverage. Considering the above attractive features, and the challenges associated with conventional bonding techniques, this article focuses on the development of high‐resolution printing interconnects in both 2D and 3D layouts and explores various printing routes available for high density integration. The article also discusses major conventional interposers/interconnects forming methods and their limitations for flexible hybrid electronics along with few examples of printed interconnects to highlight the opportunities for future.