Industrial Materials Research Articles

On the contribution of local anisotropic creep to macroscopic irradiation-induced growth in zirconium alloy polycrystals

ABSTRACT Zirconium alloys used in nuclear reactor exhibit, under fast neutron flux, a macroscopic deformation even without applied stress called irradiation induced growth. Because of the polycrystalline nature of the material, the local growth of individual grains results in strain incompatibilities yielding to intergranular stresses and thus to local creep. In order to study and understand the influence of the local anisotropic creep on the macroscopic growth behaviour, an analytical and a numerical study have been undertaken, using Voigt and self-consistent estimates and also fast Fourier transform simulations. It is shown that the anisotropic local creep has a strong influence on the effective macroscopic growth strain of the polycrystal. Especially, when the deformation is difficult along the 〈 c 〉 axis, a growth enhancement effect is observed. This phenomenon is well explained in the frame of the Voigt estimate using a reduced fibre texture. Computations conducted using a texture representative of the industrial material provide a quantitative confirmation of this enhancement effect. This work demonstrates the significant contribution of the local anisotropic creep to the macroscopic in-reactor growth strain of zirconium alloys. Highlights The local creep anisotropy has a strong influence on macroscopic irradiation growth of polycrystalline zirconium tubes. The macroscopic axial growth can be significantly enhanced by the interactions between grains when local creep deformation is prevented along the 〈 c 〉 axis. A simplified representation of grain interactions (reduced fibre texture and Voigt estimate) offers a qualitative understanding of this phenomenon. Refined estimates of the effective growth strain are provided for realistic crystallographic texture using polycrystalline unit-cell FFT computations.

Utilisation of Agricultural Wastes as Alternative Raw Materials in Fermented Food Production

The increasing demand for sustainable food production has led to a growing interest in the utilization of agricultural wastes as alternative raw materials in the fermentation industry. This systematic literature review examines the potential of agricultural by-products, such as fruit peels, vegetable scraps, and cereal residues, as substrates for fermented food production. By analyzing a wide range of studies, this review identifies the types of agricultural wastes successfully used, the fermentation processes involved, and the benefits derived from these practices, including waste reduction, cost savings, and nutritional enhancement. The review also highlights the challenges associated with the variability in waste composition, logistical constraints, and consumer acceptance. The findings suggest that the utilization of agricultural wastes in fermented food production not only contributes to environmental sustainability but also offers economic and nutritional benefits. However, further research is needed to optimize fermentation processes, assess economic feasibility, and enhance consumer acceptance. This review provides valuable insights for researchers, industry stakeholders, and policymakers interested in promoting sustainable food production practices.

Numerical and experimental investigation of silo vibration of sulfur storage

PurposeDue to the abundant use of granular materials in chemical industries, it is inevitable to store raw materials and products in bulk in silos. For this reason, much research has been carried out in the field of construction, operation and maintenance of silos. One of the important issues that must be investigated in silos is the behavior of their structure when the materials inside them are unloaded. Structural vibrations and the creation of normal noise usually discharge the granular of material from the silo. Both of phenomena are undesirable due to the problems they can cause to the structure and its surroundings. According to the said issues, this paper aims to investigate the vibration problem of the sulfur storage silo of the first refinery during discharge with the help of measuring experimental vibration data and simulating the silo model.Design/methodology/approachIn the experimental investigation, the main cause of the vibration of the 400-ton silo in the refinery is used. The mass asymmetry phenomenon when the silo is filled is also considered. The experimental results are authenticated by software analysis too.FindingsThe results showed that the natural frequency of the ninth mode is almost equal to the natural frequency of sulfur discharge from the silos and has the largest shape change in the structure and vibration range. It is also concluded that the larger sulfur silo (400 tons) should be prioritized over the smaller sulfur silo (200 tons) in the emptying program, and the 400 tons silo should never be emptied even through the 200 tons silo is empty.Originality/valueAn attempt is made to investigate the issue of vibration in sulfur storage silos in the first refinery of South Pars in the form of experimental investigation and modal analysis.

Identification of the effect of ripening conditions on the yield of rose hips and their processed products

Wild rose hip fruit, pulp, beverage, nectar, as well as technological methods and tools are taken as the object of research. Rose hips have a, bright red color and a rich chemical composition, which makes it a very important raw material for industry. However, insufficient research slows down this work and makes the use of raw materials inefficient. With this in mind, the aim was to study the mechanical and technological characteristics of the femur, which are considered important for industrial processing. The reflection of ripening conditions on the mechanical, physical and chemical properties of rose hips, as well as the influence of processing methods, especially hot processing, on the quality of the product has been established. Research has shown that the percentage of fruit cultivation in the Dashkasan region was the lowest, and the highest in the Gadabay region, and the Goygol region took an intermediate position. The Latin hardness of fruits grown in Dashkasan region was 6.41 N. Gadabay region with 5.56 N and Goygol region with 5.47 N. This indicator plays an important role in the storage and processing of fruits. As a result of the treatment, the amount of dry matter in fruit, pulp and beverage increased slightly, titratable acids, ascorbic acid and pH decreased. An increase in total phenolic compounds was observed during the initial heat treatment of the raw material and was noted to be much lower in the pulp and beverage. Hot treatment had a reducing effect on the amount of ascorbic acid, which is considered one of the main components of indicators in the thigh. The obtained results can be used in individual family farms and in the food industry

Calculation of 3D Shape of a Hyperelastic Body for Nonlinear Elasticity Models Using the Newton Method

This article discusses methods for calculating the deformations of objects with hyperelastic materials within the framework of the nonlinear elasticity theory. This topic is relevant due to the use of new technological materials in industry, and as a result, the emerging task of preliminary numerical calculations for operational reliability, research and modeling of deformation behavior. The first part provides a brief overview of the main provisions and formulas of the nonlinear elasticity theory. Then the spatial discretization of 3-dimensional objects and the calculation of the deformation gradient using the finite element method are considered. The article provides an algorithm for solving this problem, such as minimizing the functional of stored energy, and also considers the class of permissible deformations. Afterwards, a detailed description is given, along with pseudocode, of the method of implementing and calculating the minimization by Newton’s method. The last part demonstrates an example of the calculations performed, based on the developed software that allows for numerical experiments and computer modeling of deformations of hyperelastic bodies, and one of the capabilities of which is to perform these calculations using Newton’s method.

Optimising surface morphology for enhanced radiative properties in thermal energy-efficient materials

Environmental concerns related to heat-absorbing materials in the construction industry can be effectively addressed by optimising the reflectivity of incoming sunlight and thermal emissivity of materials. These radiative properties are closely tied to the surface morphology characteristics of building materials, making superficial topography a critical factor in determining their thermal and energy performance. In our research, we performed reflectance analysis in the UV-Vis-NIR-MIR region and conducted FT-IR analysis to assess the colour and reflectance behaviour of the samples, along with surface morphology and topography investigations. The data collected were utilised in a statistical study to analyse the relationship between superficial topography and thermo-optical characteristics. Our findings underscore the significant impact of surface morphology as a secondary factor influencing radiative properties. Specifically, our results indicate that large-scale components influence mid-infrared absorbance, while surface roughness is crucial in determining solar reflectance properties. Notably, an increase in roughness consistently leads to a reduction in near-infrared and visible reflectance properties by up to 17% and 8%, respectively, with no noticeable effect in the UV region. In conclusion, our research demonstrates the potential for customising and optimising surface properties to reduce energy consumption for cooling purposes and alleviate the urban heat island effect.

Steam reforming of dodecane using Ni-red mud catalyst: A sustainable approach for hydrogen production

Conventional energy sources emit huge amounts of carbon dioxide (CO2) into the atmosphere causing global warming. Hydrogen (H2) is an alternative clean energy carrier that produces only heat and water vapor upon combustion. In this work, we utilized industrial waste material (Red Mud, RM) to develop a cost-effective and efficient catalyst for steam reforming of diesel (n-dodecane as a model compound) for hydrogen production. We impregnated nickel (Ni), a prudent and effective metal, in red mud (RM) in varied proportions to employ as a catalyst for hydrogen production. The catalysts' structure was characterized by powdered X-ray Diffraction (PXRD), Fourier Transform Infrared spectroscopy (FTIR), and X-ray Photoelectron Spectroscopy (XPS). Inductively Coupled Plasma Optical Emission Spectroscopy (ICP-OES) and Electron Dispersive Spectroscopy (EDS) were used to measure the elemental composition while Scanning Electron Microscopy (SEM) was used to investigate the catalysts’ morphology. Surface area and porosity were analyzed using the N2 adsorption/desorption isotherms, and H2-Temperature Programmed Reduction (H2-TPR) to study the reducibility and interaction of Ni species to the RM. The catalysts were then evaluated for hydrogen production by the steam reforming process of n-dodecane (SRD). It was found that the catalyst with 20% Ni loading (20% Ni@RM) can produce hydrogen with selectivity as high as 75%, and stability for 20 h with a negligible decline in the catalyst performance.

Microstructural and wear properties of iron slag reinforced aluminum alloy (LM30) based composite prepared through a stir casting method

Aluminum alloys are widely used in various industries due to their as low density, high strength-to-weight ratio, and good corrosion resistance. However, their wear resistance is often inadequate for certain applications. Utilization of industrial waste materials, such as iron slag, as reinforcement in aluminum alloy matrix composites offers a sustainable approach to material development and waste management. The utilization of industrial waste materials for aluminum alloy matrix composite fabrication offers a waste utilization to material development. The loading of this reinforcement varied from 0 to 15 wt.% and different particle size range (220-140, 140-70, and 70-0 µm). A microscopic analysis indicated that the iron slag particles are spread uniformly inside the metallic matrix. There is also a reduction in the size of primary silicon, as well as morphological changes (acicular to globular shape). The wear behavior was calculated using a pin-on-disk wear set up in accordance with ASTM G99 standard. The composites were employed to dry sliding wear test under various operating conditions such as applied pressure (0.2–1.4 MPa), and sliding distance (0–3000 m). The 15F composite outperformed all other composite samples in terms of wear rate under all working conditions. When compared to the base alloy, it demonstrated a remarkable 67% drop in steady state wear rate. The enhancements in wear performance for the 15F composite were attributed to the effects of Fe slag reinforcement. The inclusion of iron slag particles induced strong interfacial bonding between matrix and reinforcement particles improving the durability of the mechanical mixed layer developed during relative motion. Importantly, the wear rate parameters of the 15F composite were similar to those of the brake drum material used in commercial applications. This emphasizes the composite suitability for usage in a variety of automobile components.

Sustainable Engineered Geopolymer Composites Utilizing Gamma-Irradiated PET and Graphene Nanoplatelets: Optimization and Performance Enhancement

Effective waste management is a matter of global concern. The utilization of widely recognized waste materials, such as plastics, rubber, and glass, in the construction industry is being investigated for their cost efficiency, enhanced material properties, and reduced environmental impact, contributing to broader sustainability efforts. This study investigates the development of an engineered geopolymer composite with a focus on sustainability by utilizing industrial waste materials. Gamma-irradiated polyethylene terephthalate was employed as a partial replacement for silica sand, while graphene nanoplatelets were incorporated to enhance composite properties and reduce environmental waste. A statistical technique known as response surface methodology was used to optimize the effects of gamma-irradiated polyethylene terephthalate and graphene nanoplatelets on the properties of the engineered geopolymer composite. Key findings indicate that gamma-irradiated polyethylene terephthalate, with higher crystallinity and robust interfacial bonding with the geopolymer matrix, significantly enhances compressive strength, elastic modulus, flexural strength, and flexural toughness. However, graphene nanoplatelets, while improving mechanical properties, reduce the ductility index. Optimal composite properties were achieved with 26.4% gamma-irradiated polyethylene terephthalate and 0.12% graphene nanoplatelets. This research underscores the potential of gamma-irradiated polyethylene terephthalate in creating high-performance, sustainable construction materials and highlights the trade-offs between mechanical reinforcement and ductility. Future research should explore the chain scission effects of gamma irradiation on polyethylene terephthalate, further optimize composite properties, and investigate mechanisms to enhance ductility, advancing the utilization of polyethylene terephthalate in sustainable construction materials.

A Reusable Past. Opportunities for the Utilization of Industrial Heritage in Salgótarján, Hungary

AbstractIndustrial heritage is not just the industrial landscape, buildings, and material objects, but also the highly complex cultural heritage created by industrial society, with many unique features. The former industrial towns of East-Central European countries have little memory of their early capitalist industrial past, and their socialist legacy is mostly seen as an unwanted and unwelcome burden. Industrial heritage preservation in Hungary was also adversely affected by the ideology of de-industrialization in the late 1980s, and this was compounded by struggles over the politics of memory. Salgótarján, as the seat of Nógrád County, is a city with county rights that has one of the worst social and economic indicators in the country, with dozens of slums, many of them on former industrial sites. The number of sites suitable for greenfield investment in the valley town is low, while the proportion of under-utilized brownfields is high. The real turning point in the development of the settlement was the opening of the mines and the mining boom in the second half of the 19th century. The opening of the mines was soon followed by the construction of larger industrial plants: the steel mill, the hollow-glass and later flat-glass factory, and the ironworks (stove factory). Initially, skilled workers were recruited from abroad, which laid the foundations for a unique society, as much of the population had no ties to the settlement, or even to Hungary—only to the work and their employer. The industrial society of Salgótarján formed a well-defined local community with a sense of identity. The management of the companies and factories, the network of workers' welfare institutions, the managed leisure programs and facilities, and of course the built environment of the colonies played a major role in all this. Under state socialism, the factories continued to operate with an artificially inflated workforce, and after the political regime change in 1989, the privatized plants closed down with dramatic abruptness, leading to social trauma and high unemployment in the settlement. The preservation and presentation of industrial heritage is also important for the city's identity while the built environment is undergoing a radical transformation, which is why buildings that are deemed worthy of preservation should be given a new function as soon as possible so that they may remain an integral part of the settlement.

Toward sustainability: Integrating experimental study and data-driven modeling for eco-friendly paver blocks containing plastic waste

Abstract Plastic waste (PW) poses a significant threat as a hazardous material, while the production of cement raises environmental concerns. It is imperative to urgently address and reduce both PW and cement usage in concrete products. Recently, several experimental studies have been performed to incorporate PW into paver blocks (PBs) as a substitute for cement. However, the experimental testing is not enough to optimize the use of waste plastic in pavers due to resource and time limitations. This study proposes an innovative approach, integrating experimental testing with machine learning to optimize PW ratios in PBs efficiently. Initially, experimental investigations are performed to examine the compressive strength (CS) of plastic sand paver blocks (PSPBs). Varied mix proportions of plastic and sand with different sizes of sand are employed. Moreover, to enhance the CS and meet the minimum requirements of ASTM C902-15 for light traffic, basalt fibers, a sustainable industrial material, are also utilized in the manufacturing process of environmentally friendly PSPB. The highest CS of 17.26 MPa is achieved by using the finest-size sand particles with a plastic-to-sand ratio of 30:70. Additionally, the inclusion of 0.5% basalt fiber, measuring 4 mm in length, yields further enhancement in outcome by significantly improving CS by 25.4% (21.65 MPa). Following that, an extensive experimental record is established, and multi-expression programming (MEP) is used to forecast the CS of PSPB. The model’s projected results are confirmed by using various statistical procedures and external validation methods. Furthermore, comprehensive parametric and sensitivity studies are conducted to assess the effectiveness of the MEP-based proposed models. The sensitivity analysis demonstrates that the size of the sand particles and the fiber content are the primary factors contributing to more than 50% of the CS in PSPB. The parametric analysis confirmed the model’s accuracy by demonstrating a comparable pattern to the experimental results. Furthermore, the results indicate that the proposed MEP-based formulation exhibits high precision with an R 2 of 0.89 and possesses a strong ability to predict. The study also provides a graphical user interface to increase the significance of ML in the practical application of handling waste management. The main aim of this research is to enhance the reuse of PW to promote sustainability and economic benefits, particularly in producing green environments with integration of machine learning and experimental investigations.

Black and Red Currant Pomaces as Raw Materials to Create Smoothies with In Vitro Health-Promoting Potential.

Pomace is a by-product resulting from the pressing of fruits and vegetables into juices, and it is typically treated as waste. Interestingly, pomace contains minimal amounts of protein and fat but is characterized by its high polyphenol and dietary fiber contents, which may have health benefits for human physiology. Therefore, they are a potentially attractive raw material for the food industry, but to our knowledge, no smoothies with their addition have been prepared and described so far. Consequently, products derived from apple juice, incorporating different doses of fresh (6% and 12%) and dried (3% and 6%) black or red currant pomace, were formulated, and their physical properties, chemical composition, bioactive compound content, and health-promoting potential (in vitro antioxidant and antidiabetic activity) were evaluated. Additionally, the products underwent sensory assessment by consumers. The fortified beverages exhibited different physical characteristics and chemical compositions than apple juice. All smoothies were characterized by higher concentrations of anthocyanins, flavonols, and procyanidin polymers compared to the base product. Moreover, 75% of them exhibited a significantly elevated phenolic acid content as well as a higher concentration of flavan-3-ols. The majority of fresh smoothies exhibited significantly higher in vitro antioxidant capacities and increased in vitro α-amylase and α-glucosidase inhibitory effects compared to the base product. The highest ABTS activity was recorded in the variant with 6% dried black currant pomace. In turn, the smoothie with 3% dried red currant pomace had the most effective FRAP effect and, together with the product containing 12% fresh black currant pomace, ORAC antioxidant activity and α-glucosidase inhibition also. The introduction of 6% dried red currant pomace led to the creation of a beverage that most effectively inhibited α-glucosidase. The study showed that the application of various types of pomace, mainly that of black currant, into apple juice enables the development of new functional products with sensory attributes that are favorably evaluated by consumers.

Assessment of Properties of Green SCC with and without Novel Additive

Concrete is the most widely used construction material in civil engineering industry because of its proved structural strength and stability when made properly. The concrete industry is constantly trying to evolve to make concrete more sustainable replacing a part of full cement with additives and Supplementary Cementitious Materials (SCMs). Each tonne of cement production releases one tonne of CO2 into the atmosphere and hence to greenhouse effect and global warming. A cost effective, alternative and innovative materials called novel additive is taken up for present study to reduce the cement consumption per m3 of concrete/SCC without reduction in strength of required grade. In this project an effort is made replacing cement content of SCC partially with Fly Ash, Ground Granulated Blast Furnace Slag (GGBS) in combination of novel additive. The study focused at studying the properties of fresh SCC and hardened SCC. The design mix proportion of 1: 2.63: 1.86 with a W/B ratio of 0.36 is taken up and 4 different mixes with different combinations of varied percentage replacement materials with 2% by weight of cement of novel additive. The properties of green SCC showed that fresh properties get enhanced through usage of mineral admixtures including a novel additive and hence, the addition of mineral admixture improve the flowability or rheology of SCC mixes. The strength of SCC achieved is ranging from 32- 46 N/mm2 for a cementitious content of 400 kg/m3 , highest being with lowest cement content with novel additive. Keywords: Rheology of SCC, Mineral Admixtures, Novel Additive, Sustainability

AC/DC Magnetic Field Sensing Based on a Piezoelectric Polymer and a Fully Printed Planar Spiral Coil.

Additive manufacturing (AM) is emerging as an eco-friendly method for minimizing waste, as the demand for responsive materials in IoT and Industry 4.0 is on the rise. Magnetoactive composites, which are manufactured through AM, facilitate nonintrusive remote sensing and actuation. Printed magnetoelectric composites are an innovative method that utilizes the synergies between magnetic and electric properties. The study of magnetoelectric effects, including the recently validated piezoinductive effect, demonstrates the generation of electric voltage through external AC and DC magnetic fields. This shift in magnetic sensors, utilizing piezoinductive effect of the piezoelectric polymer poly(vinylidene fluoride), PVDF, eliminates the need for magnetic fillers in printed devices, aligning with sustainability principles, essential for the deployment of IoT and Industry 4.0. The achieved sensitivity surpasses other studies by 100 times, showcasing linear outputs for both applied AC and DC magnetic fields. Additionally, the sensor capitalizes on the linear phase shift of the generated signal with an applied DC magnetic field, an unprecedented effect. Thus, this work introduces a remarkable magnetoactive device with a sensitivity of ST = 95.1 ± 0.9 μV Oe-1 mT-1, a significantly improved performance compared to magnetoelectric devices using polymer composites. As a functional proof of concept of the developed system, a magnetic position sensor has been demonstrated.

Hollow TiO2/Bi2MoO6 Janus-nanofibers for photo-reforming of antibiotics into carbon monoxide

Photo-reforming is an environmentally friendly technology for converting organic wastewater into carbon monoxide (CO), a potential energy source and an important industrial material. Achieving efficient photo-reforming of CO production remains a challenge due to the limitation on fast photogenerated carrier recombination. Here, the TiO2/Bi2MoO6 hetero-nanofibers are well-designed to possess unique Janus interface and ingenious hollow structure. The photo-deposition experiments demonstrated that the Janus binary interface can realize the directional migration of interfacial charges and the spatial separation of redox sites. Moreover, the hollow framework allows full exposure of the bicomponent to reactants and provides excellent optical absorption through multiple light scattering inside the tube, as evidenced by theoretical simulations via COMSOL Multiphysics. The photo-reforming yield of CO from 6000 ppm tetracycline hydrochloride (TCH) solution reaches 2.69 μmol∙g−1∙h−1 (corresponding degradation rate of 44.55 % after 5 h), about 1.44-fold superior to that of the TiO2/Bi2MoO6 core-shell hetero-nanofibers. 13C isotope tracing experiments showed that the efficiency of CO production in the photocatalytic TCH oxidation process is superior to that in carbon dioxide reduction process. Furthermore, when oxygen was introduced into the photocatalytic system, the photo-reforming CO yield from the TCH solution was significantly increased to 60.45 μmol∙g−1∙h−1, which was 22.47 and 5.12 times higher than in carbon dioxide and air atmosphere, respectively. This work provides a promising interfacial engineering to design efficient photo-reforming catalysts for energy production and environmental remediation.

Advanced evaluation of novel quinoline derivatives for corrosion inhibition of mild steel in acidic environments: A comprehensive electrochemical, computational, and surface study

Corrosion poses a significant threat to the integrity and longevity of iron and its alloys, which are crucial materials for modern industry and infrastructure. This study investigates the effectiveness of two recently synthesized inhibitors based on quinoline structures: MPQ (2-methyl-5-(propoxymethyl) quinolin-8-ol) and AAQ ((((2-aminoethyl)amino)methyl)-2-methylquinolin-8-ol) in protecting steel against environmental degradation, particularly in acidic and chloride-rich conditions such as hydrochloric acid. The inhibitors exhibited significant corrosion inhibition efficiencies of 92.37 % for MPQ and 84.13 % for AAQ, as demonstrated through electrochemical analysis. Surface characterization techniques, including SEM-EDX(Scanning Electron Microscopy with Energy Dispersive X-ray analysis), AFM (Atomic Force Microscopy), and contact angle measurements, revealed the formation of a protective barrier film that reduces the corrosion rate. Additionally, theoretical calculations using the Gaussian package provided insights into the adsorption behaviors and protective mechanisms of the inhibitors on mild steel surfaces. The findings contribute to the ongoing search for viable corrosion inhibitors, offering prospects for application in industries and critical infrastructures to enhance corrosion protection and durability.

Analysis of the Effect of Sound Dampening on Ship Engines Based on Tofu Dregs Composite Material (Glycine Max (L) Merill)

Noise in the engine room of a ship is a significant problem that can affect the health and comfort of crew members. This study aimed to evaluate the potential of tofu dregs as a sound insulation material in the form of a composite of carbon black and talak duco. The research method included making composite specimens with variations in composition, followed by testing the sound absorption coefficient using the impedance tube method. The results showed that the specimen with 30% tofu dregs, 45% carbon black, and 25% talak duco produced the highest sound absorption coefficient of 0.24. These findings show that tofu dregs have potential as an environmentally friendly and economical sound insulation material and can be used to reduce noise in ship engine rooms. This study contributes to the development of natural fiber-based insulation materials in the maritime industry.

Exploring superconductivity, supercapacitance and thermoelectric properties of NbCr[formula omitted] and its alloys with Li and Mg: A first-principles Investigation

In the present study, the superconductivity, supercapacitance, and thermoelectric properties of the NbCr2 and its alloys with Li and Mg (with alloy composition of x=0.5 in replacement with Cr atoms) have been surveyed using density functional theory. The mechanical, thermodynamic, and dynamic stability of the pure and alloy compositions have been checked by the results of the cohesive energy, enthalpy of formation energy, and phonon density of states. Moreover, the largest value of the critical temperature (Tc) which has been achieved belongs to the pure NbCr2 with a value of 13.76 K. In addition, the largest values of Tc for Li and Mg alloys are 11.83 and 3.42 K, respectively. Furthermore, the largest peak of the quantum capacitance at room temperature and as a function of the applied voltage is also related to the pure NbCr2 with a value of 676.77 μF/cm2 at the voltage of −1.86 V. In addition, the largest value of the surface charge storage occurred at the negative bias of −1.88 V with a value of −1261.27 μC/cm2. For thermoelectric properties, the largest peak of the thermoelectric power factor per relaxation time as a function of chemical potential and at room temperature belongs to Li alloy with a value 20.03 × 1016μW/(m K2 s) at the negative chemical potentials of −0.73 eV. The largest value of electronic thermal conductivity per relaxation time belongs the Li alloy at 500 K with a value of 48.71 × 1014 W/(m K s) and the largest value of lattice thermal conductivity is also related to Li alloy with the value of 22.8 W/(m K) at 100 K. All of these results represent the materials which not only have the superconductivity property but also supercapacitance and thermoelectric properties that could be useful as electrode materials in the energy storage industries.

Investigating the Effects of Temperature, Azodicarbonamide, Boron Nitride, and Multilayer Film/Foam Coextrusion on the Properties of a Poly(Hydroxyalkanoate)/Poly(Lactic acid) Blend

AbstractPoly(hydroxyalkanoates) (PHAs) are emerging as sustainable materials in packaging and medical device industries. Nevertheless, the high cost and the need to improve the mechanical properties have limited their widespread use. Blending with other bio-based polymers, such as poly(lactic acid) (PLA), has been proposed in previous studies. This study investigates the effects of temperature, azodicarbonamide (AZ, foaming agent), boron nitride (BN, filler), and multilayer film/foam coextrusion on the properties of a blend containing an amorphous PHA and PLA. The effect of twin-screw micro-compounder temperature (185 °C & 205 °C) and BN concentrations of 1, 2, 3, 5, and 10 wt% (185 °C) on the properties of the PHA/PLA blend were investigated using differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), and tensile testing. Design of experiments (DoE) was used to find the optimal concentrations of AZ and BN (205 °C) using JMP® software. The response surface analysis predicted an optimal design based on the target response levels (modulus, tensile strength, strain at break, and toughness). This formulation was prepared and characterized using DSC, TGA, tensile, and melt flow index (MFI) measurements. Finally, this formulation was processed via film/foam coextrusion and examined using scanning electron microscopy (SEM) and density measurements. This study demonstrated that AZ and BN can be used to manipulate the mechanical properties and crystallinity of PHA/PLA blends, while reducing the overall material cost via density reduction (20–21% for the optimal formulation). Furthermore, reducing the concentration of AZ using the I-optimal design in this study could alleviate the toxicity concerns for food packaging.

Enhancing the safety and thermal stability of polyurethane filling materials in the mining industry through expanded graphite-based hydrated salts

The utilization of Polyurethane foaming materials (PUF) to seal coal fissures presents a significant challenge due to the substantial heat generated during the reaction process, potentially accelerating fires. In order to study this issue, we propose a novel low-heat polymerization mechanism by incorporating a hydrated salt phase change composite that efficiently absorbs polymerization heat while encapsulating liquid water using expanded graphite (EG). Our findings demonstrate that integrating 10 % EG-6 leak-free phase change material effectively reduces the reaction temperature to a safer 91.4 °C, ensuring minimal impact on the inherent properties of the material. Thorough analyses via TGA and in-situ IR experiments reveal a noteworthy 17 °C elevation in the modified PUF's thermodynamic characteristic temperature point. Additionally, we developed a mixed combustion model of PUF and coal to investigate the gas generation pattern of polyurethane in the mine-filled state where fire occurs. Specifically, the introduction of PUF reduced O2 consumption and CO production while increasing CO2 and C2H4 production, which is consistent with the reality of increased carbon hydrocarbon gases being monitored downhole. These findings suggest a synergistic, mutually beneficial relationship between the two during the low-temperature oxidation stage. This research offers perspectives for the development of polymer materials for coal mines and the safe application of actual filling.