Temperature Resistance Research Articles

Assessment of bacteria-based self-healing concrete through experimental investigations — a sustainable approach

This study aims to evaluate the destructive and non-destructive strength parameters of bacterial concrete with different grades (M20, M25, M30) and cell counts (10^5 and 10^6 cells/ml) using Bacillus subtilis. Additionally, cost analysis and cost–benefit comparisons were conducted for each mix. The effectiveness of B. subtilis in resisting high temperatures was also examined. Findings indicate a 25–40% increase in strength parameters in bacterial concrete compared to conventional concrete. Bacterial mixes consistently showed velocities above 4.45 km/s, indicating excellent quality, surpassing conventional concrete. Notably, bacteria with a cell count of 10^5 cells/ml exhibited greater strength than 10^6 cells/ml across all grades. Cantabro loss tests revealed a 15–25% reduction in wear and tear for bacterial concrete. The bacterial specimens also showed significantly lower strength loss at higher temperatures. This study underscores the potential of bacterial-based self-healing concrete for specific construction applications, offering high temperature resistance, increased strength, and reduced wear and tear.

Experimental Study on Surfactant–Polymer Flooding After Viscosity Reduction for Heavy Oil in Matured Reservoir

An advanced enhanced oil recovery (EOR) method was investigated, employing a surfactant–polymer (SP) system in combination with a viscosity reducer for application in a heavy oil reservoir within the Haiwaihe Block, Liaohe Oilfield, in China. Significant advantages were observed through the combination of LPS-3 (an anionic surfactant) and OAB (a betaine surfactant) in reducing interfacial tension and enhancing emulsion stability, with the optimal results achieved at the ratio of 9:1. The BRH-325 polymer was found to exhibit superior viscosity enhancement, temperature resistance, and long-term stability. Graphene nanowedges were utilized as a viscosity reducer, leading to a viscosity reduction in heavy oil of 97.43%, while stability was maintained over a two-hour period. The efficacy of the combined system was validated through core flooding experiments, resulting in a recovery efficiency improvement of up to 32.7%. It is suggested that the integration of viscosity reduction and SP flooding could serve as a promising approach for improving recovery in mature heavy oil reservoirs, supporting a transition toward environmentally sustainable, non-thermal recovery methods.

All-Organic Aramid Films with High Temperature Resistance and Electrical Insulation by Introducing Interfacial Hydrogen Bonds.

Although aramid nanofibers (ANFs) consist of rigid poly(terephthalic acid terephthalamide) molecular chains with good high temperature resistance for aerospace and other high-temperature applications, it has poor electrical insulation properties due to internal defects. Currently, the main method to improve the electrical insulation properties is to introduce wide band gap two-dimensional (2D) fillers, such as Boron Nitride Nanosheets (BNNS) or mica flakes, but this inevitably affects the mechanical properties and optical transparency. Cellulose acetate (CA) is originated from acetylation of natural cellulose, and the higher number of hydrogen bond donors on the molecular chain enables it to interbond with many polymers. In this study, CA was introduced into ANFs films, and the all-organic aramid films were prepared by blade coating method. A high dielectric constant of 14.4 as well as a low dielectric loss (0.062 @103 Hz) were obtained, and the dielectric loss of all films was lower than that of the ANFs films, which is attributed to the introduction of interfacial hydrogen bonds that suppressed the loss. In addition, the introduction of interfacial hydrogen bonds introduced deep traps inside the all-organic aramid films, which further improved in breakdown strength from 216.11 MV/m for ANFs film to 367.8 MV/m for the 5 CA film. The prepared all-organic aramid films also showed excellent flexibility as well as high temperature resistance, and the electrical insulation performance under different extreme environments was still higher than that of the ANFs films. This study provides a method for the preparation of high temperature resistant and electrically insulating films, which have great potential applications in fields relating to high temperature circumstance.

IoT-Integrated Smart Energy Meter for Industrial Energy Monitoring

- Electric energy monitoring in industrial loads like pressure die casting is extremely vital especially due to their energy handling requirements. This work details the conception and implementation of an Internet of Things based Smart Energy Meter designed specifically for Industrial purposes. The system can measure three-phase voltage, current (up to 100A) and furnace temperatures with the aid of Resistance Temperature detectors. Using the ESP32 microcontroller and the Blynk Internet of things platform, the meter enables the collection, storage, and displaying of the data on the Cloud in real time. In order to enhance accuracy, the hardware architecture combines ZMPT101B voltage sensors, SCT-013-000 current sensors and a MAX31865 Resistance Temperature detector module. The software part of the system uses the Open-Energy Monitor library which contains various algorithms for energy calculations and transfers data over Serial peripheral interface/Wi-Fi protocols. The system has been tested in an industrial setting and the results have shown an accuracy of measurement within a tolerance of 1% for electrical and thermal characteristics plus a normal operation for variable conditions. The presented results prove the possibility of intra- system energy optimization and the industrial prospects of its application. Promising research directions include the addition of predictive maintenance features based on machine learning as well as more efficient scaling to support many different industrial applications. Key Words: Smart Energy Meter, IoT, ESP32, RTD Sensors, Energy Monitoring, Industrial Automation

The Production and Durability of Superhydrophobic Foamed Concrete

The durability problem caused by the high-water absorption of foamed concrete restricts its further development and application. This study aimed to improve the durability of foamed concrete by transforming its performance from hydrophilic to superhydrophobic. Firstly, polydimethylsiloxane-modified superhydrophobic bulk foamed concrete was produced through physical foaming. Then, multiple durability tests, like mechanical wear, acid–alkali–saline resistance, ultraviolet aging, and extreme temperatures resistance tests, were carried out to assess its performance. Finally, the mechanism of superhydrophobicity also was studied. The results indicated that the volumetric and capillary water absorption of the superhydrophobic foamed concrete decreased by 72.4% and 92.6%, respectively, compared to ordinary foamed concrete. The dry densities of ordinary foamed concrete and superhydrophobic foamed concrete were 720 kg/m3 and 850 kg/m3, respectively. Superhydrophobic foamed concrete exhibited excellent wear resistance and resistance to ultraviolet aging. The contact angles after 10 m polishing and 168 h of ultraviolet irradiation were 152.1° and 152.2°, respectively. High temperature increased its hydrophobicity, and the contact angle increased to 157.1° at 200 °C. Additionally, electrochemical tests proved its better chloride ion corrosion resistance, and the corrosion potential and corrosion current of the superhydrophobic foamed concrete after 7 days were −0.190 V and 3.177 × 10−6 A, respectively. Therefore, the superhydrophobic bulk modification technique shows considerable potential for enhancing the durability of foamed concrete applied in various scenarios.

Modified Ziman Resistivity Formula and Temperature Dependence of Intrinsic Resistivity: A Case Study of Janus WSH Monolayer

Modified Ziman Resistivity Formula and Temperature Dependence of Intrinsic Resistivity: A Case Study of Janus WSH Monolayer

Functional groups control of metal by electron beam irradiation and its application to superhydrophobic surface

Since electron beam irradiation tended to increase metal wettability, significantly decreasing surface wettability remained difficult. In this paper, low-energy electron beam irradiation was used to significantly decrease the surface wettability of 316 L stainless steel, and the mechanism of modifying functional groups was revealed. The experimental results demonstrated that the hydrophilic functional groups C-O-C, O-C=O, and -OH had a significant decrease in contents, and the hydrophobic C-C/C-H group contents increased dramatically. The contact angle increased from 50° to 91°. This was due to the interaction of excited secondary electrons with precursor molecules, as well as fragmented carbon radicals and other fragments adsorbed on the surface, which generated new chemical bonds. The effects of various metal materials and microtextures on secondary electron emission were investigated. It was observed that a higher excitation coefficient for secondary electrons corresponds to a greater increase in the contact angle. The addition of different types of precursor molecules has the effect of controlling the wettability of electron beam irradiation. Nitrogen reduced the effect of electron beam irradiation modification, and hydrocarbon molecules increased the effect. A superhydrophobic surface with a contact angle of 160° and a sliding angle of 6° was successfully prepared by combining a pitting texture with hydrocarbon molecules. It has excellent wear resistance, high temperature resistance, and ultraviolet radiation resistance.

Novel Polymer Development Creates New High-Temperature, High-Pressure Cement Slurry Suspending Agent

Summary A high-temperature suspending agent with temperature resistance up to 200°C has been developed to address the challenges of high-temperature, high-density cement slurry (2.0–2.6g/cm3) settling and destabilization during cementing in deep wells (4500–6000 m) and ultradeep wells (>6000 m). This suspending agent is designed to introduce modified nano-silica (nano-SiO2) and long hydrophobic side-chain temperature-sensitive monomers. The inclusion of modified nano-SiO2 enhances the temperature resistance of the suspending agent and improves the suspension stability of solid-phase particles in high-density cement slurries. Concurrently, the long hydrophobic side chains increase the viscosity of the cement slurry at high temperatures through hydrophobic bonding. The synergistic effect of these components can delay settling of high-density cement slurries at high temperatures. In performance evaluations adhering to American Petroleum Institute (API) standards, the addition of 0.6 wt% of the suspending agent to a high-density cement slurry (density of 2.35 g/cm³) reduced the density difference between the top and bottom of the slurry from 0.897 g/cm³ to 0.028 g/cm³ after curing at 200°C, surpassing the local (Chinese) standard requirement of 0.05 g/cm³. This contributes to maintaining the overall uniformity of solid-phase particles in high-density cement slurry at high temperatures. It ensures the proper development of slurry consistency and cement strength properties. This advancement can help to reduce the risks associated with deep well cementing, supporting the quality of cementing operations in deep and ultradeep wells, and holds promise for starting some field tests.

Modification and Performance Evaluation of Radio Frequency Identification Technology in High-Temperature and High-Pressure Environments

Summary As oil and gas exploration progresses into deeper and ultradeep territories, the radio frequency identification (RFID) tags used in drillpipes are required to demonstrate enhanced resilience to elevated temperatures and pressures. Current research on tags for ultrahigh temperature and ultrahigh pressure environments is relatively scarce. This study focuses on the application of RFID in deeper drilling operations, aiming to further enhance the tags’ temperature and pressure resistance to meet the application requirements. Numerical simulations were conducted to assess the mechanical properties of RFID tags installed on drillpipes of varying dimensions under conditions of elevated temperatures and pressures. This process enabled the optimization of the dimensions of the RFID tags and installation holes. The optimal dimensions for the RFID tag were determined to be φ24.3×7 mm, with the corresponding installation hole being φ24.3×11 mm. To evaluate the high-temperature endurance of the RFID tags, they were subjected to a temperature of 200℃ for a period of time, after which a maximum temperature of 230℃ was applied. Furthermore, a bespoke high-temperature and high-pressure apparatus was used to conduct a 7-day endurance test at 200℃ and 200 MPa. The findings demonstrated that the RFID tags exhibited reliable performance even when subjected to an extreme temperature of 230℃. Furthermore, the RFID tags exhibited consistent performance when subjected to prolonged periods of high temperature and pressure. The efficacy of the RFID tags was further validated through an 11-well field experiment, wherein the embedded tags exhibited no indications of detachment or deterioration. Once removed from the apparatus, the tags were able to be read automatically in real time, thus enabling the automated collection of data from the drillpipe in actual operating conditions. The findings of this study provide valuable insights and establish a foundation for the design and application of RFID tags in the challenging environments of deep and ultradeep oil and gas exploration.

Ethylene vinyl acetate as a multifunctional compatibilizer for natural rubber/cis-1,4-polybutadiene rubber blends with enhanced compatibility, filler dispersion and mechanical properties

The blending of natural rubber (NR) with cis-1,4-polybutadiene rubber (BR) has gained widespread attention due to its potential in enhancing the low temperature resistance and abrasion resistance of NR. However, the incompatibility between NR and BR as well as the non-uniform distribution of fillers often have an adverse impact on the mechanical properties. Herein, we propose a facile approach to modulate the multi-scale structures in NR/BR blends including polymer compatibility and filler distribution by introducing ethylene vinyl acetate (EVA) with varying vinyl acetate (VA) content as multifunctional compatibilizers. The results indicate that the cure characteristics (i.e., processability) and mechanical properties of NR/BR blends can be readily tailored through adjustment of the VA content in EVA. When the VA content in EVA is increased to 18% (EVA-18), the NR/BR blends simultaneously exhibit favorable processability and mechanical properties. The microstructural analysis demonstrates that the introduction of EVA-18 not only enhances the compatibility between NR and BR with significantly reduced domain size, but also improves fillers dispersion in the rubber matrix. The presence of EVA-18 at concentrations up to 20 parts per hundred of rubber (phr) in NR/BR vulcanizates improves the mechanical properties by approximately 24% compared to un-compatibilized NR/BR vulcanizates, which is superior to the most present studies. This work will be beneficial for the development of NR/BR blends in the industry and provide a guideline for designing efficient compatibilizers for other immiscible rubber blends.Graphical abstract

Enhancing temperature resistance of calcium aluminate cement through carbonated steel slag

Enhancing temperature resistance of calcium aluminate cement through carbonated steel slag

3D printing of regolith-based epoxy composites with excellent temperature resistance and mechanical strength

3D printing of regolith-based epoxy composites with excellent temperature resistance and mechanical strength

Optimization of the Preparation Process of Crosslinked Polyvinyl Alcohol and Its Thermal Stability in Cementing Slurry

This study focuses on addressing the limitations of fluid loss additive in cement slurry under higher temperatures. The synthesis process of glutaraldehyde-crosslinked polyvinyl alcohol (PVA) was optimized to develop an efficient fluid loss additive for oil well cement slurries. Using one-factor experiments and the uniform design method, the optimal synthesis parameters were established: a reaction temperature of 50 °C; an acid concentration of 1 mol/L; a PVA mass concentration of 8%; a molar ratio of glutaraldehyde to PVA hydroxyl group of 1.47; and a crosslinking degree of 1.49%. The optimized crosslinked PVA demonstrated the ability to control API fluid loss within 50 mL when applied at 1% concentration in cement slurry under conditions of 30–110 °C and 6.9 MPa. Rheological analysis at medium and high temperatures revealed improved slurry properties, including smooth thickening curves and unaffected compressive strength. Further analyses, including thermogravimetric analysis (TGA), Zeta potential testing, and scanning electron microscopy (SEM), revealed that the crosslinked PVA hydrogel remained thermally stable up to 260 °C. Chemical crosslinking transformed the linear PVA into a network structure, enhancing its molecular weight, viscoelasticity, and thermal stability. This thermal resistance mechanism is attributed to the hydrogel’s high-strength reticular structure which forms a uniform, dense, and highly stable adsorption layer, thereby improving both the additive’s efficiency and the hydrogel’s temperature resistance.

Thermal Effect of Firebrand Accumulation in Ceramic Roof Tiles

This paper presents investigations concerning the thermal firebrand reaction due to its accumulation in the top of ceramic roof tiles, commonly applied to the exterior of dwellings in southern Europe. A large-scale fire experiment is conducted, wherein firebrands are placed above the tiles and temperature readings are taken from multiple layers of the building components. The selection of materials for the roof layer assembly was based on recommendations for either fire resistance or high temperature behaviour. The test follows the fire setup recommended in the California Building Code for firebrand deposition. This investigation will allow for a more accurate verification of the firebrand reaction in the roof, including the type of ignition, the creation of smoke and droplets, and even their mechanical ability to withstand elevated temperatures.

Pressurised water flow in fractured permafrost rocks revealed by borehole temperature, electrical resistivity tomography, and piezometric pressure

Abstract. Rock slope instabilities and failures from permafrost rocks are among the most significant alpine hazards in a changing climate and represent considerable threats to high-alpine infrastructure. While permafrost degradation is commonly attributed to rising air temperature and slow thermal heat propagation in rocks, the profound impact of water flow in bedrock permafrost on warming processes is increasingly recognised. However, quantifying the role of water flow remains challenging, primarily due to the complexities associated with direct observation and the transient nature of water dynamics in rock slope systems. To overcome the lack of a quantitative assessment, we combine datasets of rock temperature measured in two deep boreholes (2016–2023), with electrical resistivity tomography measurements repeated monthly in 2013 and 2023; the site-specific temperature–resistivity relation determined in the laboratory with samples from the study area; and borehole piezometer data. Field measurements were carried out at the permafrost-affected north flank of the Kitzsteinhorn (Hohe Tauern range, Austria), which is characterised by significant water outflow from open fractures during the melt season. Borehole temperature data demonstrate a seasonal maximum of the permafrost active layer of 4–5 m. They further show abrupt temperature changes (∼ 0.2–0.7 °C) at 2, 3, and 5 m depth during periods with enhanced water flow and temperature regime changes between 2016–2019 and 2020–2022 at 10 and 15 m depth, which cannot be explained solely by conductive heat transfer. Electrical resistivity measurements repeated monthly reveal a massive decrease in resistivity from June to July and the initiation of a low-resistivity (< 4 kΩ m) zone in the lower part of the rock slope in June, gradually expanding to higher rock slope sections until September. We hypothesise that the reduction in electrical resistivity of more than an order of magnitude, which coincides with abrupt changes in borehole temperature and periods of high water heads up to 11.8 m, provides certain evidence of snowmelt water infiltration into the rockwall becoming pressurised within a widespread fracture network during the thawing season. This study shows that, in addition to slow thermal heat conduction, permafrost rocks are subjected to sudden push-like warming events and long-lasting rock temperature regime changes, favouring accelerated bottom-up permafrost degradation and contributing to the build-up of hydrostatic pressure, potentially leading to slope instability.

Superstrong Lightweight Aerogel with Supercontinuous Layer by Surface Reaction.

Breaking the thermal, mechanical and lightweight performance limit of aerogels has pivotal significance on thermal protection, new energy utilization, high-temperature catalysis, structural engineering, and physics, but is severely limited by the serious discrete characteristics between grain boundary and nano-units interfaces. Herein, a thermodynamically driven surface reaction and confined crystallization process is reported to synthesize a centimeter-scale supercontinuous ZrO2 nanolayer on ZrO2-SiO2 fiber aerogel surface, which significantly improved its thermal and mechanical properties with density almost unchanged (≈26 mgcm-3). Systematic structure analysis confirms that the supercontinuous layer achieves a close connection between grains and fibers through Zr─O─Si bonds. The as-prepared aerogel exhibits record-breaking specific strength (≈84615 Nmkg-1, can support up to ≈227272 times aerogel mass) and dynamic impact resistance (withstanding impacts up to 500 times aerogel mass and up to 200 cycling stability at 80% strain). Besides, its temperature resistance has also been greatly optimized (400°C enhancement, stability at 1500°C). This work will provide a new perspective for exploring the limits of lightweight, high strength, and thermal properties of solid materials.

Electrical conductivity of multilayered Cu/Nb composites fabricated by accumulative roll bonding

The electrical conductivity of nanolayered copper/niobium composites fabricated using accumulative roll bonding was investigated as a function of layer thickness. Cu/Nb was used as a model system to evaluate the processing-structure–property relationship stemming from the accumulative roll bonding process. The physical properties were compared against samples of individual average layer heights ranging from 193 to 25 nm. The electrical resistivity was measured over a temperature range of ∼3–300 K. Analysis on the role of interfaces on temperature dependence is conducted including the residual resistivity ratio and temperature coefficient of resistivity. It was found that electrical resistivity increases with decreasing layer height.

Low Temperature Atomic Layer Deposition of (00l)‐Oriented Elemental Bismuth

This study presents the first successful demonstration of growing elemental bismuth (Bi) thin films via thermal atomic layer deposition (ALD) using Bi(NMe2)3 as the precursor and Sb(SiMe3)3 as the co‐reactant. The films were deposited at a relatively low temperature of 100 °C, with a growth per cycle (GPC) of 0.31‐0.34 Å/cycle. Island formation marked the initial growth stages, with surface coverage reaching around 80% after 1000 cycles and full coverage between 2000 and 2500 cycles. Morphological analysis revealed that the Bi grains expanded and became more defined as the number of ALD cycles increased. This coalescence is further supported by X‐ray diffraction (XRD) patterns, which show a preferential shift in growth orientation from the (012) plane to the (003) plane as the film thickness increases. X‐ray photoemission spectroscopy (XPS) confirmed the presence of metallic Bi with minimal surface oxidation. Temperature‐dependent sheet resistance measurements highlight the semimetallic nature of Bi, with a room temperature resistivity of ≈200 µΩcm for the 2500 cycles Bi. Temperature‐dependent sheet resistance was also associated with a transition in carrier‐type dominance from electrons at higher temperatures to holes at lower temperatures.

Low Temperature Atomic Layer Deposition of (00l)-Oriented Elemental Bismuth.

This study presents the first successful demonstration of growing elemental bismuth (Bi) thin films via thermal atomic layer deposition (ALD) using Bi(NMe2)3 as the precursor and Sb(SiMe3)3 as the co-reactant. The films were deposited at a relatively low temperature of 100 °C, with a growth per cycle (GPC) of 0.31-0.34 Å/cycle. Island formation marked the initial growth stages, with surface coverage reaching around 80% after 1000 cycles and full coverage between 2000 and 2500 cycles. Morphological analysis revealed that the Bi grains expanded and became more defined as the number of ALD cycles increased. This coalescence is further supported by X-ray diffraction (XRD) patterns, which show a preferential shift in growth orientation from the (012) plane to the (003) plane as the film thickness increases. X-ray photoemission spectroscopy (XPS) confirmed the presence of metallic Bi with minimal surface oxidation. Temperature-dependent sheet resistance measurements highlight the semimetallic nature of Bi, with a room temperature resistivity of ≈200 µΩcm for the 2500 cycles Bi. Temperature-dependent sheet resistance was also associated with a transition in carrier-type dominance from electrons at higher temperatures to holes at lower temperatures.

ИЗУЧЕНИЕ КОЛЛЕКЦИИ СОРТООБРАЗЦОВ ОЗИМОЙ ПШЕНИЦЫ ЗАРУБЕЖНОЙ СЕЛЕКЦИИ В УСЛОВИЯХ ЗАПАДНОЙ СИБИРИ

The purpose of the study is to conduct a breeding assessment of variety samples and identify sources of valuable traits for winter wheat breeding. A collection of 52 varieties of winter soft wheat of different ecological and geographical origins was studied. Field and laboratory studies were carried out in 2020–2022 on the experimental field of the Omsk State Agrarian University in the conditions of the southern forest-steppe of Western Siberia. Sowing was carried out in fallows at generally accepted sowing times. The research results showed that American and Turkish varieties had the highest yield (284 and 297 g/m2), winter hardiness (6–6.5 points) and resistance to snow mold (5–5.5 points). Mexican lines had greater variability in the studied traits in comparison with other groups of variety samples and are recommended for breeding to expand the genotypic diversity of domestic varieties for drought resistance and grain quality. Bulgarian samples are unique in grain quality (on average they contain: protein – 17.1 %; gluten – 37.2; ash content – 1.81; gluten index – 95.8 % and sedimentation – 68 ml). Varieties and lines have been identified as adaptive and promising genotypes for winter wheat breeding in Western Siberia: Mv-Ispan, Mv-Bojtar, Mv-Dandar, SYWolf, KS13DH00 37-66, KS13DH00 30-32, CO13D 1299, WBLL1*2 / Tukuru // Billings. These varieties formed the highest yield (341–453 g/m2) in dry growing conditions, had higher rates and a smooth increase in biomass (NDVI = 0.37–0.68), high drought resistance (6.0–7.0 points ) and lower leaf surface temperature (≥ 35.3 °C).