Search

Purpose: To evaluate the effect of three different curing protocols based on different ratios of self-curing and light-curing periods on the bond strength and nanoleakage of fiber posts luted with dual-curing selfadhesive cements. Materials and Methods: A total of 48 single-root teeth were endodontically treated and obturated, and an 8-mm post space was prepared with dedicated drills. Specimens were randomly divided into two groups according to the self-adhesive cement employed: group 1 (G1) = PANAVIA SA Plus (Kuraray Noritake), and group 2 (G2) = Bifix SE (VOCO). The specimens were further divided into three subgroups (n = 8 each) according to the light-curing protocol applied: no light-curing (SG1), 20 seconds of light-curing 20 seconds after cement injection (SG2), and 20 seconds of light-curing 120 seconds after cement injection (SG3). Slices of 1-mm thickness were prepared for the pushout test and nanoleakage analyses of the coronal and apical regions after 24 hours of storage in artificial saliva. Results were statistically analyzed with threeway ANOVA and Tukey post hoc tests. Statistical significance was set for P < .05. Results: Three-way ANOVA analysis showed that the factors of cement (P = .02) and curing protocol (P < .001) had a significant influence on bond strength. Tukey post hoc test reported that light-curing 120 seconds after injection showed higher bond strength compared to both no light-curing and photoactivation after 20 seconds. Conclusion: To achieve the highest bond strength with self-adhesive cements, photoactivation with a 120-second delay after mixing is required. There is no difference between light-curing immediately and light-curing 20 seconds after mixing. [ABSTRACT FROM AUTHOR]

AbstractIn modern lightweight construction, multi-material design has become increasingly important. An increasing number of structures are being adhered because adhesive joining technology can be used regardless of the material of the bonded partners. Owing to the dissimilar coefficients of thermal expansion, thermally induced relative displacements of the adherend occur during heat curing. Following these pre-deformations, changes in the mechanical properties of adhesive joints were observed. In this study, thick adherend shear specimens were used to induce defined relative displacements in the shear plane during the curing process. Quasi-static tests showed a directional dependence in the pre-deformation. This anisotropic behaviour was investigated in detail. Results showed that shear band formation occurred in the adhesive owing to the load during the cooling of joined structures. The restructuring of the polymer structure leads to changes in the mechanical properties. [ABSTRACT FROM AUTHOR]

Highlights During the manufacturing of thermoset‐based carbon fiber‐reinforced polymer (CFRP) structures, a curing process involving thermal, chemical, and mechanical interactions occurs. This process gives rise to micro‐scale residual stresses due to differences in fiber and resin properties, leading to decreased mechanical properties compared to nominal values. A trans‐scale analysis method utilizing the reduced order model (ROM) is applied in this study to establish a connection between the manufacturing and in‐service processes for unidirectional CFRP (UD‐CFRP). By employing this method, the evolution of residual stresses at the micro‐scale during UD‐CFRP manufacturing is predicted, and the impact of these residual stresses on structural performance during service is assessed. Specifically, the manufacturing‐induced residual stresses reduce the material strength by a minimum of 19.31%, while also exploring the correlation between macro‐scale and micro‐scale failures. Notably, the computational cost of this method is significantly lower, with a reduction factor of 103 compared to the finite element method. Empirical evidence supports the effectiveness of this method in accurately predicting outcomes throughout both the manufacturing and in‐service processes. Trans‐scale analysis method links composites manufacturing simulation to in‐service performance. Highly efficient trans‐scale method excels in cost, accuracy, consistency, and convergence. Residual stresses from the curing process significantly impact matrix safety. [ABSTRACT FROM AUTHOR]

Chipping has emerged as a significant issue in semiconductor manufacturing, particularly during the dicing process. The existing conventional single-sided wafer mounting technique does not have sufficient holding capability which contributes to instability during dicing and causes higher chipping performance. The objective of the study is to develop a novel wafer mounting technique that can hold the wafer firmly during dicing and improve the chipping performance. In the experiment, chipping and vibration performance during the dicing process on novel double-sided semi and full-sandwich wafer mounting were investigated and compared with the conventional single-sided wafer mounting technique. Chipping was measured using high power scope and ImageJ software while the vibration was initiated using the NI 9234 Sound-Vibration Module and SDT1-028K Piezoelectric film. Implementing extended surface tape coverage on double-sided UV mounting tape for the full sandwich wafer mounting technique resulted in superior wafer gripping during dicing and produced the lowest topside and backside wafer chipping performance. The novel double-sided full sandwich wafer mounting technique has demonstrated higher wafer holding capability, resulting in lower vibration during dicing and improved overall chipping performance [ABSTRACT FROM AUTHOR]

A time–temperature‐transformation diagram is created for the curing reaction of a diglycidylether bisphenol A (DGEBA)‐based epoxy resin. It results from a kinetic analysis performed by means of dynamical differential scanning calorimetry (DSC) measurements; a gelation curve determined with isothermal and dynamical rheological tests; and a vitrification curve obtained from temperature‐modulated dynamic DSC measurements. The resulting diagram is validated by comparison of isothermal measurements with the corresponding calculated curves. [ABSTRACT FROM AUTHOR]

Electrochemical impedance spectroscopy (EIS) was employed in an attempt to gain insight into the mechanisms of ethyl 2-cyanoacrylate (ECA) curing (polymerisation) and bonding on aluminium alloy 2024 metal. EIS can detect ionic movement, adsorption processes, charge transfer and storage occurring at an adhesive/substrate interface and/or in a bulk bond line during curing. Low-frequency capacitance measurements demonstrated sensitivity to surface polymerisation reactions and were modelled using an equivalent circuit model with two time constants in series. At a frequency of 1 kHz, changes in the dielectric polymer could be readily followed with time, confirmed by employing a crown ether to accelerate the polymerisation process. Hydrolytic degradation of poly-ECA bonds at a stainless steel interface was also investigated. An equivalent circuit model containing a number of circuit components comprising pore, charge transfer and diffusional impedances, along with polymer film, double layer and diffusional capacitances (represented by constant phase elements), was developed. Three regions were identified in the frequency domain and ascribed to processes taking place at the polymer/electrolyte and polymer/metal oxide interfaces. In short, EIS can be employed to follow the rate of polymerisation of ethyl-2-cyanoacrylate and also the degradation of the resulting polymer in saline solution. [ABSTRACT FROM AUTHOR]

The silicon-aluminum ratio of the molecular sieves is a crucial control index for the quality of synthetic molecular sieves. Here a fast, simple and reliable sample preparation method, referred to as pouring and curing method, is described for determining the silicon-aluminum ratio of high silicon molecular sieves by energy dispersive x-ray fluorescence (EDXRF). Resin is used as the carrier with the addition of a curing agent, so that the sample powder is embedded in the resin matrix. By measuring sixteen random positions of the same cured sample, the homogeneity of the sample was evaluated to ensure the stability of the results. A double logarithmic calibration curve of the analysis line ratio and the corresponding concentration ratio of silicon and aluminum was established according to the binary ratio method. The results by EDXRF and inductively coupled plasma-optical emission spectrometer (ICP-OES) were compared with a relative standard error from 2.934 to 6.777%. The good precision shows that the pouring and curing method is a suitable for measuring the silicon-aluminum ratio of molecular sieves. [ABSTRACT FROM AUTHOR]

Purpose: The study aims to ascertain the influence of solder conductive particle types and substrate widths on the current carrying capability of flex-on-board (FOB) assemblies. By comparing Sn58Bi and SAC305 particles and varying substrate widths, the research sought to provide insights into the stability and performance of solder joints under different scenarios, particularly in high-power applications. Design/methodology/approach: The study used a comprehensive design/methodology, encompassing the investigation of solder conductive particle types (Sn58Bi and SAC305) and substrate widths on the current carrying capability of FOB assembly. Stable solder joints were obtained by manipulating the curing speed of anisotropic conductive films for both particle types. Various tests were conducted, including current carrying capability assessments under differing conditions. Findings: The study revealed that larger substrate widths yielded higher current carrying capability due to increased contact area and reduced contact resistance. Notably, solder joints remained stable beyond the solder melting temperature due to encapsulation by cured epoxy resin. SAC305 solder joints exhibited superior current carrying capability over Sn58Bi in continuous high-voltage conditions. The results emphasized the stability of SAC305 solder joints and their suitability for robust interconnections in high-power FOB assemblies. Originality/value: This study contributes by offering a comprehensive assessment of the impact of solder particle types and substrate widths on solder joint performance in FOB assemblies. The finding that SAC305 joints outperform Sn58Bi under continuous high-voltage conditions adds significant value. Moreover, the observation of stable solder joints beyond solder melting temperature due to resin encapsulation introduces a novel aspect to solder joint reliability. These insights provide valuable guidance for designing robust and high-performance interconnections in demanding applications. [ABSTRACT FROM AUTHOR]

A series of epoxidized 1,2‐polybutadienes with various degrees of epoxidation are synthesized by the reaction of 1,2‐polybutadienes and m‐chloroperbenzoic acid. Additionally, the curing behavior of epoxidized 1,2‐polybutadienes with a cationic initiator and the relationship between epoxidation ratios and the dielectric, thermal, and mechanical properties of the cured materials are examined. [ABSTRACT FROM AUTHOR]

The use of membrane-forming curing compounds on fresh concrete has been widely adopted by many States' Departments of Transportation as it is feasible where there is a deficiency of water, on sloping surfaces where curing with water is challenging, and in cases where large areas like pavement have to be cured. However, the evaluation of the curing compound application effectiveness is difficult because most of the evaluation test methods are not performed during the early age of the concrete. Moreover, the ASTM C156 standards test of water retention for the qualification of curing compounds has met criticism as the moisture retention is performed only on the mortar specimens, with a fixed application rate and curing condition. Therefore, in this study, the embedded resistance technique was used as a test replacement for the moisture retention test to assess concrete curing. The findings from this study showed that a correlation can be found between the moisture retention test and the embedded resistance test. Based on the findings, the embedded resistance test could be a suitable replacement for the moisture loss test, because the test is much simpler and quicker to be performed both in the lab and in the field. [ABSTRACT FROM AUTHOR]

The current technology for curing high-performance composites, such as those used in industries like such as aeronautics and the automotive industry, is based on the use of autoclaves, where the material is cured by external heating, in large ovens. This type of curing requires enormous amounts of energy, of which only a small part is invested in the actual curing of the material, and the rest is mainly used for heating and maintaining the temperature of the autoclave. An alternative method that entails a lower energy cost compared to the traditional methodology is curing through the Joule effect, in which an electric current is passed through the material, so that it acquires temperature from the inside due to the passage of current through the carbon fibres, triggering and accelerating the curing process of the composite. While Joule curing may provide a much more efficient and faster curing, a control technology is needed to ensure that temperatures all throughout the composite match the temperature programme. In this work, a procedure has been developed to control the Joule effect curing of carbon fibre/epoxy composites in order to compare, by means of differential scanning calorimetry (DSC) and dynamic mechanical analysis (DMA), the curing obtained by this method with that obtained by the traditional oven curing method. [ABSTRACT FROM AUTHOR]

Curing modulation is one of the important processes in tobacco production, so it is crucial to recognize tobacco flue-curing states effectively and accurately. This study created a dataset of the complete tobacco flue-curing process in a bulk curing barn environment and proposed a lightweight recognition model based on a feature skip connections module. Firstly, the image data was enhanced using a color correction matrix, which was used to recover the true color of the tobacco leaf in order to reduce the misidentification of adjacent states. Secondly, the convolutional neural network model proposed in this paper introduced Spatially Separable convolution to enhance the extraction of tobacco leaf texture features. Then, the standard convolution in Short-Term Dense Concatenate (STDC) was replaced with Depthwise Separable Convolutional blocks with different expansion rates to reduce the number of model parameters and FLOPs (Floating Point Operations Per Second). Finally, the Tobacco Flue-Curing State Recognition Network (TFSNet) was constructed by combining the SimAm attention mechanism. The experimental results showed that the model accuracy was improved by 1.63 percentage points after the color correction process. The recognition accuracy of TFSNet for the seven states of tobacco flue-curing was as high as 98.71%. The number of params and the FLOPs of the TFSNet model were 203,058 and 172.39 M, which were 98.18% and 90.55% lower than that of the ResNet18 model, respectively. The size of the model was 0.78 mb, and the time consumed per frame was only 21 ms. Compared with the mainstream model, TFSNet significantly improved the detection speed while maintaining high accuracy, and it provided effective technical support for the intelligentization of the tobacco flue-curing process. [ABSTRACT FROM AUTHOR]

This study aimed to investigate the effects of different curing temperatures on the hydration and mechanical properties of high-volume fly ash (HVFA) concrete. The key variables were curing temperature (13 °C, 23 °C, 43 °C) and fly ash (FA) content (0%, 35%, 55%). The hydration characteristics of HVFA cement were examined by evaluating the setting time and heat of hydration under different curing temperatures. The mechanical properties of HVFA concrete were analyzed by preparing concrete specimens at various curing temperatures and measuring the compressive strength at 7, 28, 56, and 91 days. The results indicated that concrete with high FA content was more sensitive to curing temperature compared to ordinary Portland cement. [ABSTRACT FROM AUTHOR]

This study investigates the influence of expanded perlite (EP) replacement rate and curing methods on the compressive strength of concrete at different ages through the uniaxial compression test. The stress–strain full curve model of concrete considering EP replacement rate is established, and a damage evolution model considering curing conditions, EP replacement rate and load effects is developed based on the damage theory. The results show that: (1) The lack of water in concrete curing will have a huge negative impact on its mechanical properties, and the internal curing effect of pre‐wet EP can effectively alleviate the phenomenon of incomplete hydration. (2) Under dry curing, the addition of EP will reduce the early compressive strength of concrete, while its internal curing effect can improve the compressive strength of concrete in the later stages. (3) The C & C model and the Guozhenhai model are used to construct the segmented model in the rising and falling sections, and the model parameter formula is deduced by the replacement rate. The model can fully describe the stress–strain relationship of expanded perlite concrete (EPC). (4) The damage evolution model of EPC shows an "S" shape growth curve. Dry curing and EP replacement can both reduce the development rate of damage, while the former has a more significant impact. [ABSTRACT FROM AUTHOR]

The kinetics of polymerization of epoxy resin ED-20 cured with a polyethylene polyamine hardener modified with silicone rubber, tris(trimethylsiloxy) phenylsilane, octamethyl cyclotetrasiloxane is studied. A more rapid decrease in the amount of epoxy groups in systems modified with silicon-contained additives during polymerization is observed. A differential equation describing the change in changes in the concentration of epoxy groups with the polymerization time is proposed. The found exact solution to the proposed equation describes adequately the experimental data. The modification of epoxy binder reduces the time and temperature of the maximum heat release during the curing. The modification with the addition of tris(trimethylsiloxy) phenylsilane leads to the maximum increase in heat release. A differential equation describing the change in the heat release temperature with the curing time is formulated. The exact solution to the equation formulated is found, which is applied to estimate the curing end time of the compositions. [ABSTRACT FROM AUTHOR]

Concrete bridge deck cracking can cause serious serviceability issues during a bridge's design life and compromise a bridge's structural strength. Early age concrete bridge deck cracking occurs within a month of the concrete deck being placed and prior to live load application. It can typically be attributed to two factors: (1) construction practices; and (2) concrete shrinkage. This article examines the continuous deck placement sequence approach and its influence on early age concrete bridge deck cracking. Although the continuous deck placement process is commonly used, studies related to stresses induced during this process and the potential for deck cracking when using this construction method are very limited to work conducted overseas. Consequently, a time-dependent analysis considering the continuous bridge deck placement sequence at a steel composite bridge is presented in this article to help explain possible causes of early age bridge deck cracking. The modular ratio approach discussed in the Eurocode 4 is incorporated to approximate the early age concrete elastic modulus. To show the significance of using a continuous placement sequence, tensile stresses along the bridge length centerline are compared with the allowable tensile stress at two times, six and twenty-seven days after the bridge deck construction is initiated. Additionally, the article includes a simplified approach for calculating maximum bridge thermal stresses. The study results in this article will serve to aid engineers in understanding possible factors resulting in early age bridge deck cracking when a continuous deck placement sequence is used for bridge deck construction. Practical Applications: Early age bridge deck cracking can typically be attributed to construction practices and concrete shrinkage. Most bridges are constructed using a sequential deck placement where the concrete bridge deck is placed in discontinuous segments in an order to minimize tensile stresses developing in the concrete bridge deck. Conversely, a continuous deck placement entails placing the concrete bridge deck from one end of the bridge to the other end continuously. Contractors prefer using a continuous deck placement because of the method's reduced construction time. The Arkansas Department of Transportation (ARDOT) has identified early age concrete bridge deck cracking at a disproportionate number of continuous steel girder bridges constructed using a continuous deck placement. Early age concrete bridge deck cracking develops when tensile stresses in the concrete bridge deck exceed the concrete's tensile strength. During the bridge construction phase, concrete self-weight, construction loads, and thermal shrinkage are the primary load contributors to early age concrete bridge deck tensile stress. Since most continuous girder steel bridges consist of multiple short spans, early age concrete bridge deck tensile stress is primarily due to resistance to thermal shrinkage. An equation is derived in the article to calculate an approximate value for the thermal shrinkage stress. Thermal shrinkage cracking is averted by implementing proper curing methods to ensure the concrete tensile strength exceeds the induced tensile stress. Proper curing includes moist curing and minimizing moisture loss by using concrete curing blankets. [ABSTRACT FROM AUTHOR]

The bond–slip behavior of concrete pile–cemented soil interface is crucial for load transfer analysis of stiffened deep cement mixing piles, which is greatly influenced by ground temperature and age during long-term curing. However, the thermal–temporal effect on the frictional characteristics of this interface remains unclear. In this paper, an element-scale specimen of concrete pile–cemented soil interface was first designed. Then interfacial shear tests were performed on batches of samples subjected to varied curing temperatures (T) and ages (t) to obtain interfacial bond–slip (τ‒s) curves. The test results showed that the interfacial peak shear strength (τu) increased with the growth of T and t. Based on the experimental observations, a strength development model for τu considering the thermal effect was established. Subsequently, a disturbed state concept (DSC)-based constitutive model incorporating the thermal–temporal effect was proposed for the investigated interface. Both prepeak and postpeak stages of the τ‒s curves can be effectively described by the developed DSC model, exhibiting robust performance in fitting and predicting experimental results. Finally, the DSC model was cross-validated by the interfacial τ‒s data sets collected from reported experimental publications. Across all data sets, the coefficient of determination (R2) exceeded 0.9, and the mean absolute percentage error of τu remained below 10% when comparing predictions with measurements, which strongly highlights the generalization capability of the DSC model. [ABSTRACT FROM AUTHOR]

Post-harvest losses in onions pose a serious challenge, urging exploration of innovative strategies. The scrutiny explores post-harvest technology's pivotal role in curbing losses, vital for food security and economic stability. Grading, sorting, and modern storage methods are outlined, including recent advances like gamma ray irradiation. Additionally, innovative approaches to managing onion diseases are discussed. Insightfulness into traditional and modern storage methods including recent advances are also brought out. As a corollary, this comprehensive review underscores the critical importance of post-harvest technology in reducing onion losses and enhancing the overall efficiency and sustainability of the onion supply chain. It emphasizes the need for improved post-harvest management to minimize losses, highlighting essential recommendations for agricultural stakeholders. [ABSTRACT FROM AUTHOR]

Present research critically investigates drying sensitivity and cement hydration resumption in recycled aggregate concrete (RAC). To determine minimum post-curing time for optimum strength resumption in RAC, a curing ratio (δ) is introduced. Curing ratio is defined as the ratio between post-curing duration and delay time before curing. Drying sensitivity of RAC is observed significantly lower than NAC. The maximum strength loss under drying conditions is 25.9% in RAC (OPC) and 23.2% in RAC (PPC). Strength criteria determine the curing ratios of RAC (OPC) and RAC (PPC) as 2.22 and 0.30. The maximum delay time for RAC (OPC) and RAC (PPC) is determined at 8 days and 21 days with a minimum post-curing for 17.76 and 6.63 days. The longest allowable delay produces ion penetration less than 1000 Coulombs, resistivity greater than 208 ohm-m, superior structural integrity and internal compactness, and sorptivity comparable to RACs cured after a shorter delay. [ABSTRACT FROM AUTHOR]

High-strength alumina (Al2O3 ) was utilized as a reinforcing phase to improve the strength of hydroxyapatite (HA), a bioactive material, but the HA-Al2O3 ceramics prepared by traditional hydrothermal method could not achieve the precise control of pore size and porosity, whereas the light curing additive manufacturing technology could achieve the high precision molding of HA-Al2O3 ceramics through the high-performance photocurable slurry. The state of HA-Al2O3 slurry is adjusted by the addition of dispersant, photoinitiator, and photoabsorbent to alleviate the severe scattering effect caused by the refractive index mismatch between HA powder, Al2O3 powder, and photosensitive resin. In this study, the effects of the type and content of photoinitiator and dispersant on the slurry were explored. The rheological and curing properties of the slurry are first improved and then weakened with the addition of both, and the optimal dosages of photoinitiator and dispersant are 0. 5% and 4% (mass fraction), respectively. The effects of two light absorbers, graphite and methyl yellow, on improving the printing accuracy were compared. Although graphite improves the printing accuracy and rheology of the slurry, it reduces the printing quality, so the dosage of 5.0 x 10-5 methyl yellow is determined, and finally HA-Al2O3 slurries suitable for high precision printing are obtained. [ABSTRACT FROM AUTHOR]

Several research works have been carried out to improve cold mix asphalt (CMA), being an eco-friendly construction; however, very few attempts have been made on curing of loose CMA mixture before the compaction process for preparing the specimens that simulate the actual field condition. The present study aims to assess the effect of various curing parameters (curing temperature, curing duration and curing condition) on loose CMA mixture for improvement in the curing rate and strength of compacted samples. The curing rate of the loose mixture was satisfactory in the temperature range of 40–60°C; however, curing in the oven at 50°C closely simulated the local field condition in normal weather. After investigating different processes for effective curing of the loose mix, the protocol with initial 1% moisture loss in the air at room temperature, followed by 3% moisture loss in the oven at 50°C resulted in the optimum CMA properties. [ABSTRACT FROM AUTHOR]

Copyright of Environmental Geochemistry & Health is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Durable building materials are essential for sustainability in construction projects, aiming to reduce environmental damage from the start to the end of a building's life. Reducing the use of Portland cement in concrete production is essential because of the significant CO2 emissions generated globally during its production process. This study investigates the workability, compressive strength, and water absorption of concrete when Portland cement is partially substituted with waste glass powder (WGP) and recycled concrete powder (RCP). These two waste powders can be used to partially substitute Portland cement in order to produce environmentally friendly concrete. The activity of the particles in concrete made from these two waste powders is mostly determined by the type and rate of the powders, as well as the curing methods. Therefore, the current research examines how different curing conditions impact the workability, compressive strength, and water absorption characteristics of this innovative eco-friendly concrete that includes the abovementioned waste powders. According to the experimental results obtained, adequate strength can be achieved using an appropriate replacement level of the powders and curing methods. Therefore, the application of these two recycled mineral admixtures in concrete can save Portland cement and has certain environmental and economic benefits. [ABSTRACT FROM AUTHOR]

High-temperature adhesives find extensive application in diverse domains, encompassing repairs, production processes, and material joining. However, achieving their curing at ambient temperatures remains a formidable challenge due to the inherent requirement of elevated temperatures, typically exceeding 500 °C, for the curing reaction. To overcome this limitation, in this study, we developed a distinctive inorganic phosphate-based composite adhesive by incorporating dual-functional calcium monoaluminate (CA) into a traditional adhesive blend comprising Al(H2PO4)3 and MgO. This distinctive approach significantly diminishes the curing temperature, enabling it to occur at room temperature. Firstly, CA's facile hydration reaction effectively scavenges surrounding water molecules, thereby accelerating the dehydration curing process of Al(H2PO4)3. Secondly, as hydration is an exothermic process, it locally generates heat around the Al(H2PO4)3, fostering optimal conditions for its curing reaction. Moreover, the adhesive's strength is substantially bolstered through the strategic inclusion of Nano-Al2O3 (enhancing the availability of reaction sites) and Nano-SiO2 (improving overall stability). As a demonstration, the adhesive formulation with added CA containing 2% Nano-Al2O3 and 2% Nano-SiO2 achieved a remarkable tensile strength of 32.48 MPa at room temperature, underscoring its potential as an efficient solution for various practical adhesive applications. The adhesive prepared in this study harnesses the hydration properties of CA to absorb moisture and release substantial heat, introducing a novel method for ambient temperature curing. This development promises to broaden its applications in refractory materials, coatings, and equipment repair. [ABSTRACT FROM AUTHOR]

Highlights The occurrence of process‐induced deformations of composites laminates is challenging for assembly accuracy and may lead to a service life reduction of parts. However, it can be obviously mitigated through different optimization strategies on the basis of the accurate curing process simulation. In this study, a stacking sequence optimization strategy is proposed and applied to multi‐layer thick asymmetric laminates. The shapes of deformed laminate plates are experimentally investigated in virtue of the three‐dimensional coordinate measuring machine. The thermo‐chemical–mechanical behaviors of plates are first verified through the comparisons of model predicted and experimental process‐induced deformations. Then the nonlinear control formula achieved through the regression model is proposed for the direct relationship between stacking sequences and process‐induced deformations. Finally, the required solutions are generated by solving the control formula. With the comparisons between the average deformations before and after optimizations, it is found that the magnitudes of deformations are significantly reduced, especially when the unoptimizated deformations are large. The thermo‐chemical–mechanical behavior can be described in the curing process simulation model. The deformed shapes of multi‐layer thick asymmetric laminate plates are measured by a three‐dimensional coordinate measuring machine. The stacking sequence optimization strategy is implemented by introducing a nonlinear control formula. [ABSTRACT FROM AUTHOR]

Heat‐resistant chocolate is of much interest to confectionery companies for marketing in tropical areas. Methods exist to produce heat‐resistant chocolate by exposing the product to high relative humidity (RH) and increased temperatures. The overall objective of this research project was to explore the curing of white chocolate (30% whole milk powder, 44% sucrose, and 26% cocoa butter) to make it heat resistant and able to be picked up at 33 and 55°C. The curing involved storing solid chocolate samples at 83% RH at 29°C for 1 week. Moisture content before and after curing was measured using the Karl Fischer technique. Force required to penetrate (hardness) was measured at 29°C using a texturometer. Curing samples of white chocolate bars at a lower relative humidity (50% RH at 18°C for 12 weeks or 50% RH at 29°C for 12 weeks) also resulted in a heat‐resistant chocolate that exhibited internal structure, as monitored by SEM. The moisture content in heat‐resistant milk chocolate increased from an average value of 0.84% to 4.6% during the curing process. Curing increased the penetration force, indicating the development of internal structure. This study showed that heat resistance in white chocolate can be achieved by curing solid chocolate samples at controlled humidity and temperature conditions. [ABSTRACT FROM AUTHOR]

By simulating the high-temperature service environment of tunnel lining concrete, this study investigates the compressive and impermeable properties of tunnel lining concrete at 20, 60, and ambient temperature of 80 ℃ for 3, 7, and 28 d, and analyzes the changes in compressive and impermeable properties of tunnel lining concrete under high-temperature environmental conditions, in order to provide theoretical support and empirical reference for the construction of tunnel lining concrete under high-temperature environmental conditions. The results indicate that a high-temperature curing environment can improve the compressive strength of tunnel lining concrete at 3 and 7 d, but an 80 ℃ high-temperature curing environment can reduce the compressive strength of tunnel lining concrete at 28 d；With the increase of ultrafine powder content, the compressive strength of tunnel lining concrete first increases and then decreases. When the content is 30%, the compressive strength of concrete is the highest；With the increase of temperature and the addition of ultrafine powder, the electrical flux of tunnel lining concrete generally shows a downward trend. In the same mix, the modal chord length of concrete specimens does not show a significant change with the increase of curing temperature, but the average chord length decreases with the increase of curing temperature. [ABSTRACT FROM AUTHOR]

In this paper, we introduce a novel approach for defect detection in hammering inspections using Unmanned Aerial Vehicles (UAVs). Despite the promising application of UAVs for inspecting hard-to-reach structures, like bridges, their efficiency is often compromised by the significant ego noise produced by their motor-propeller systems. This noise complicates the discrimination between healthy and defective hammering sounds. In previous research, methods to improve robustness through supervised learning have been proposed; however, these methods require the labeling of hammering sounds by skilled inspectors to train the discrimination model. To overcome this problem, we propose an ego-noise reduction method based on propeller vibrations. By reducing ego noise and thereby making the characteristics of hammering sound more dramatically clear, we enable unsupervised defect detection amidst ego noise. Our experiments with concrete specimens demonstrate that our technique achieves defect detection with an accuracy on par with the supervised method. The proposed method proves especially beneficial for hammering inspections, in which the domain gap–the variability in acoustic signatures of hammering sounds caused by differences in concrete mix ratios and curing conditions from one site to another–presents a significant challenge. Our approach effectively adapts to these variations, ensuring reliable defect detection across diverse construction environments. [ABSTRACT FROM AUTHOR]

The cure kinetics of various epoxy resin mixtures, comprising a bisphenol epoxy, two epoxy modifiers, and two hardening agents derived from cardanol technology, were investigated through differential scanning calorimetry (DSC). The development of these mixtures aimed to achieve epoxy materials with a substantial bio-content up to 50% for potential automotive applications, aligning with the 2019 European Regulation on climate neutrality and CO2 emission. The Friedman isoconversional method was employed to determine key kinetic parameters, such as activation energy and pre-exponential factor, providing insights into the cross-linking process and the Kamal–Sourour model was used to describe and predict the kinetics of the chemical reactions. This empirical approach was implemented to forecast the curing process for the specific oven curing cycle utilised. Additionally, tensile tests revealed promising results showcasing materials' viability against conventional counterparts. Overall, this investigation offers a comprehensive understanding of the cure kinetics, mechanical behaviour, and thermal properties of the novel epoxy–novolac blends, contributing to the development of high-performance materials for sustainable automotive applications. [ABSTRACT FROM AUTHOR]

Unsaturated polyester resin (UPR) systems are extensively used in composite materials for applications in the transportation, marine, and infrastructure sectors. There are continually evolving formulations of UPRs that need to be evaluated and optimized for processing. Differential Scanning Calorimetry (DSC) provides valuable insight into the non-isothermal and isothermal behavior of UPRs within a prescribed temperature range. In the present work, non-isothermal DSC tests were carried out between temperatures of 0.0 °C and 250 °C, through different heating and cooling ramp rates. The isothermal DSC tests were carried out between 0.0 and 170 °C. The instantaneous rate of cure of the tested temperatures were measured. The application of an autocatalytic model in a calculator was used to simulate curing behaviors under different processing conditions. As the temperature increased from 10 °C up to 170 °C, the rate of cure reduced, and the heat of reaction increased. The simulated cure behavior from the DSC data showed that the degree of cure (α) maximum value of 71.25% was achieved at the highest heating temperature of 85 °C. For the low heating temperature, i.e., 5 °C, the maximum degree of cure (α) did not exceed 12% because there was not enough heat to activate the catalyst to crosslink further. [ABSTRACT FROM AUTHOR]

Softening and subsequent deformation are significant challenges in additive manufacturing of thermal-curable thermosets. This study proposes an approach to address these issues, involving the preparation of thermosetting composite powders with distinct curing temperatures, the utilization of cold spray additive manufacturing (CSAM) for sample fabrication, and the implementation of stepwise curing for each component. To validate the feasibility of this approach, two single-component thermosetting powders P1 and P2 and their composite powder C were subjected to CSAM and stepwise curing. From the sample morphology observation and deposition/curing mechanism investigation based on thermomechanical analysis and differential scanning calorimetry, it is found that severe plastic deformation occurs during the CSAM process, accompanied by heat generation, leading to local melting to promote a good bond at the contact surface of the particles and form small pores. During the progressive curing, the samples printed using C demonstrate superior deformation resistance compared with those using P1 and P2, and the curing time is reduced from 16.7 h to 1.5 h, due to the sequential curing reactions of P1 and P2 components in composite C, allowing the uncured P2 and cured P1 to alternately remain solid for providing structural support and minimizing deformation. [ABSTRACT FROM AUTHOR]

For the assembly problems caused by the curing deformation of L-shaped composite structure, a simulation model of the curing deformation of composite part considering tool–part interaction was established. Firstly, the shear slip effect of the tool on the composite structure during curing process was characterized by setting the friction coefficient with the maximum shear stress. Secondly, the effects of composite anisotropy, material thermal expansion and contraction, and matrix chemical shrinkage on the curing deformation were considered. Finally, the cure hardening instantaneously linear elastic model was used to realize the curing deformation simulation calculation under the premise of effectively improving the computational efficiency. Then, the validity of the simulation model was verified by designing experiments of curing deformation of L-shaped structures with different thicknesses and different lay-up sequences. The experimental and simulation analysis results were compared with a maximum error of − 20.8% and an average error of − 7.35%. Results show that for L-shaped structural parts prepared by aluminum tool, the tool–part interaction exacerbates the curing deformation situation of the structure, and the structural stiffness plays an important role in this deformation. [ABSTRACT FROM AUTHOR]

In the current study, the effects of cement or lime content, fibre content, partial cement or lime replacement with zeolite and curing time on the Unconfined Compressive Strength (UCS) of sand have been investigated. The results reveal that increasing cement or lime content increases Maximum Dry Density (MDD) and Optimum Water Content (OMC). However, increasing zeolite replacement percentage decreases MDD and OMC. Increasing the fibre content from 0 to 4% reduces the MDD and increases OMC. The optimum combination of the stabiliser and fibre has been derived from an array of tests. Results comparison shows the 0.5% fibre content and 8% stabiliser results in maximum effect. Also, the optimum percentage of 80% replacement of lime and 30% and 40% replacement of the cement with zeolite leads to the maximum UCS. Observing failure patterns demonstrates the influential performance of fibre content such as controlling the crack length and brittle behaviour. Moreover, SEM analysis was conducted to compare the microscale behaviour. [ABSTRACT FROM AUTHOR]

Chloroprene rubber (CR) is an expensive and frequently used material in many industries. Thus, a blend of natural rubber (NR) and CR can be used to balance cost and product performance. In this research, the primary objective is to achieve the ideal blend of CR/NR rubber for automotive industry by simultaneously optimizing various response variables, including hardness, tensile strength (TS), vulcanization index (CRI), torque difference and Tan δ. This optimization process is carried out using response surface methodology (RSM) and desirability functions. The study delves into examining the influence of accelerators, retarders, curatives, and the ratio of NR in the final batch on both curing characteristics and mechanical properties. The investigation is conducted through the application of analysis of variance (ANOVA) and linear/nonlinear regression models with the assistance of Design Expert 11. When the quantities of the fillers, TMTM80, DP80, S80, and CTPI80, are at their optimum levels of 1.08, 1.78, 3.5, and 0.96 PHR, respectively, and the NR ratio in the final masterbatch is around 27%, the estimated values for Tan δ, hardness, and TS are approximately 0.144, 55.183 Shore A, and 21.085 MPa, respectively. The observations from the validation experiments align with the predicted outcomes, as all response variables fall within the 95% prediction interval. It is noteworthy to mention that prior research has not attempted simultaneous optimization for CR/NR blend, incorporating these fillers. [ABSTRACT FROM AUTHOR]

The curing cycle of natural rubber (NR) with a conventional accelerated sulfur system (CV) generally exhibits three phases. The induction phase, the crosslinking phase, and the reversion phase. Prolonged curing of NR/CV system even at a temperature of 150 °C can show reversion. Many research reports are available in the literature with reference to the reversion behavior and the subsequent network modifications of natural rubber with accelerated sulfur. However, the literature regarding post-reversion curing behavior is scanty. This article describes the post-reversion upturn of natural rubber with a conventional accelerator sulfur system at a higher curing temperature. A network rebuilding after collapsing the initially formed network due to reversion was identified as the primary reason for the post-reversion upturn. The dynamic rheological testing capability of the Rubber Process Analyzer (RPA) was employed to characterize the network formed during curing, reversion and post-reversion phases. The cure-strain sweep data from the RPA indicated that the shear storage modulus (G′) of the broken network increased due to the post-reversion upturn. The chemical crosslink densities of the samples were also found to increase due to the upturn curing behavior. From these experimental results and the information conceived from the previous literature, two plausible mechanisms have been proposed to interpret the post-reversion upturn cure behavior. [ABSTRACT FROM AUTHOR]

Metal‐to‐metal adhesives are vital across diverse sectors including automotive, aerospace, and industrial assembly. However, traditional adhesion detection methods are mainly based on the fracture mechanism, posing challenges for nondestructive detection. Here, a nondestructive method that leverages electrical signals to monitor the adhesion state of metal interfaces in real‐time is presented. The approach utilizes detectable adhesives (DA) synthesized from poly(ionic liquid) (PIL), which not only exhibit robust adhesion properties (4.9 MPa) but also function as ionic conductors. By correlating changes in capacitance and resistance with the adhesive state, the method allows for in situ monitoring of the curing process, prediction of adhesion strength, and early detection of potential failures. This dual‐sensing capability, combining electrical and mechanical aspects, enhances understanding of adhesive behavior in diverse conditions, presenting a fresh approach for digitally transforming adhesive technologies. [ABSTRACT FROM AUTHOR]

Copyright of China Forest Products Industry is the property of China Forest Products Industry Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Silicone Material is the property of Silicone Material Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

There is an increasing demand for superhydrophobic surfaces due to their unique properties like self-cleaning, anti-icing, corrosion resistance, etc. The development of polyurethane (PU)-based superhydrophobic coating has garnered significant attention for aircraft applications. Polyurethane (PU) topcoat is widely used in aircraft and is hydrophilic in nature with a water contact angle (WCA) of 75 ± 3°. In the present work, a hydrophilic PU clear coat on aircraft-grade aluminum substrate is transformed to a superhydrophobic (SHP) surface by spraying environmentally friendly hydrophobically modified silica nanoparticles (HSiNps) oonto a PU layer that was partially cured in a hot air oven at 60°C for 1.5 h. The SHP surface exhibited a WCA of 162 ± 3° and a sliding angle (SA) of 8 ± 3°. With the incorporation of HSiNps, micro – nano dual-scale surface roughness is created and the surface roughness of the PU coating is increased from 0.35 to 2.42 µm. The coating exhibits good adhesion (5B) with excellent water repelling property and remains thermally stable and superhydrophobic even after subjecting it to 100°C for one week. Durability of the coatings is studied by immersing the coatings in various liquids. The retention of superhydrophobic property after anti-fogging, water sprinkler, and sand paper abrasion tests further demonstrate the robustness of the coating. Polyurethane-based SHP coating is prepared using hydrophobized silica nanoparticles. Partially cured polyurethane coating help in grafting of silica nanoparticles on to the surface. The coatings are durable to heat, solvents, corrosive liquids and sand paper abrasion [ABSTRACT FROM AUTHOR]

Sand production along with the oil/gas detrimentally affects the oil production rate, downhole & subsurface facilities. Mechanical equipment and various chemicals like epoxy resin, furan resin, phenolic resin, etc. are used in the industry to reduce or eliminate this problem. In the present study, a blend of organic and inorganic silicates are used to consolidate loose sand in the presence and absence of crude oil using a core flooding apparatus. The effects of chemical concentration, pH, curing temperature and time, and the presence of residual oil on the consolidation treatment results such as compressive strength and permeability retention, were investigated and optimized. FT-IR and FE-SEM characterization techniques were employed to investigate the interaction between the chemical molecules and the sand grains. The current binding agent exhibited a viscosity of less than 6 cP at room temperature, which facilitates efficient pumping of binding agent into the desired formation through the well bore. The developed mixture demonstrated consolidation properties across all pH conditions. Furthermore, during the experimental investigation, the curing time and temperature was carefully optimized at 12 h and 423.15K, respectively to achieve the highest compressive strength of 2021 psi while achieving the permeability retention of 64%. The current chemical system exhibited improved consolidation capacity and can be effectively utilized for sand consolidation treatment in high-temperature formations. [ABSTRACT FROM AUTHOR]

This study examined the mechanical behavior characteristics of cold recycled emulsified asphalt bases with RAP 76% and emulsified asphalt 3%, in different cure time, i.e., 0, 7, 14 and 28 days and evaluated in terms of the resilient modulus (RM) and permanent deformation (PD) based on repeated load triaxial tests. The results demonstrated that in the first 7 days, the RM increased by 80% compared to the freshly compacted material and after this period, the subsequent increases were not as significant, ranging, from 10.9% to 19.4%, that shows that initical cure time significantly influences the RM behavior of the mixtures. However, the mixtures showed considerable permanent deformations, even after 28 days of curing. This indicates that the use of asphalt emulsion, with prolonged curing, improves the mechanical properties of the mixture but does not entirely resolve the issue of permanent deformation in cold reclaimed asphalt mixture (CRAM). The plastic deformation behavior observed in the triaxial tests must be taken into account when designing pavements containing RAP and asphalt emulsion. [ABSTRACT FROM AUTHOR]

Copyright of World Nuclear Geoscience is the property of World Nuclear Geoscience Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Poly(epichlorohydrin‐co‐ethylene oxide‐co‐allyl glycidyl ether) (GECO) elastomers have gained importance in recent years thanks to improved synthesis methods. The effect of curing agents, fillers, and ionizing radiation on the mechanical properties of GECO elastomers has been studied in detail, however, the effect of the molecular and structural architecture of GECO on their elastomers' properties is not well studied. The main aim of this study was to prepare GECO elastomers with a certain recipe and to examine the effects of molecular and structural parameters of these polymers on the cure characteristics, mechanical properties, temperature scanning stress relaxation, and damping properties. The results showed that among the three monomers, the ethylene oxide ratio was the more important parameter affecting the cure characteristics and cure degree of GECO elastomers. It was also observed that the energy absorption and damping properties vary with the ethylene oxide ratio, crosslink density, and long chain branching. The temperature scanning stress relaxation behavior of GECO elastomers was observed to have almost the same relative behavior, regardless of crosslink density and branching. The results suggest that the temperature‐induced relaxation behavior does not change with the type and ratio of the monomers that make up the GECO. [ABSTRACT FROM AUTHOR]

Silicon‐containing arylacetylene resin (PSA)‐matrix composites hold great potential for aerospace applications due to their excellent heat resistance. In recent years, many PSAs with specific functions have been designed via materials genome approach (MGA), and appropriate resin transfer molding (RTM) curing processes need to be screened to strike a balance between low cost and high quality. In this study, a novel tool based on finite element curing simulation and multiobjective genetic algorithm was developed to optimize the RTM curing process for novel PSA‐matrix composites. The silicon‐containing fluorenylacetylene resin (PSA‐VBF) was selected as the object to systematically characterize its apparent curing kinetics. To address the problem of explosive polymerization of the resin at the injection port during the RTM process, a multiobjective optimization of the curing process using a genetic algorithm was performed to obtain the Pareto front with the maximum temperature gradient at the injection port of the resin, the maximum degree of cure gradient of the composites, and the process time as the objectives. A global sensitivity analysis was also conducted to identify the key parameters. The results demonstrate that the optimized curing process can significantly reduce the temperature gradient and the curing degree gradient with improved curing efficiency. [ABSTRACT FROM AUTHOR]

Novel elastomers are made by reaction of hydroxyl‐terminated polyacrylic ester (HyTemp) with polyethylene glycol (PEG, number of ethylene glycol units 1, 3, 6, 9) based cross‐linkers. The influence of the cross‐linker length, the HyTemp/cross‐linker (w/w) ratio and the cross‐linking accelerator trifluoromethanesulfonate scandium salt (ScTFMS) on the structure and the properties of the materials are studied. The cross‐linker length has not influence on the glass transition (Tg) of the products because of the presence of the flexible PEG units that cancels out the cross‐linking effect associated to a shift to higher Tg. A two‐domain structure is seen by the presence of a dual Tg in samples cured with ScTFMS. Mathematical analysis of the modulated differential scanning calorimetry curves offers for the first time the possibility to identify/confirm structural differences in complex three‐dimensional polymeric structures. Scanning electron microscopy and swelling experiments in ethyl acetate respectively reveal an increase in the pore size (1.13 to 5.48 nm) and in the absorption ability of the elastomers cured with different types and quantities of PEG cross‐linker. The new elastomeric materials are exhibiting a rubbery state over a wide temperature range and absorptivity for the potential recovery of pollutants in soil and/or water. [ABSTRACT FROM AUTHOR]

Based on the physical and thermal properties, plaster of paris (P-O-P) has been used in many applications including the medical field and infrastructure constructions for over thousands of years around the world. With the increased applications developing new technology to real-time monitor, the changes from slurry to the solidified materials are important for evaluating the curing processes and the performances under various applications. Based on the newly developed Vipulanandan electrical characterization method, the resistivity was identified as the critical material property for the P-O-P with water-to-binder ratio of 0.5. In order to make the highly sensing piezoresistive P-O-P, another innovative approach, up to 0.05% of carbon fibers (CF), was added and tested. The measured initial resistivity immediately after mixing was sensitive to the amount of carbon fiber addition. During curing, the changes in resistivity were monitored using the two probe method and alternative current at 300 kHz. During curing, the resistivity changes were sensitive to the amount of fibers added to the P-O-P and was modeled using the Vipulanandan curing model. Solidified P-O-P with and without carbon fibers were tested under compressive loading after 1, 7 and 28 days of curing under the room condition (23 °C and relative humidity of 50%). The one day and 28 days the average compressive strengths of P-O-P without fibers were 2.14 and 6.04 MPa, respectively. The piezoresistive compressive strain at failure for the P-O-P without CF was less than 1%, and with the addition of 0.02 and 0.05% CF, it not only increased the compressive strength but also substantially increased the piezoresistive compressive axial strain at peak stress. After 28 days of curing, the P-O-P with 0.05% CF the axial piezoresistive strain at the peak stress was 345%, it increased by over 500 times (50,000%) compared to the P-O-P without CF, clearly showing the very high sensitivity of the P-O-P develop in this study with CF addition (smart P-O-P). Vipulanandan piezoresistive p-q model was used to predict the piezoresistive behavior of the smart P-O-P and it predicted the behavior very well based on the root mean square error. Vipulanandan correlation model was used to predict the changes in the compressive strength and compressive piezoresistive failure strain with curing time and also the long-term property limits were predicted. [ABSTRACT FROM AUTHOR]

Cemented paste backfill (CPB) is prevented from freezing by antifreeze during transport in subzero temperatures. However, there is yet to be a study on the mechanical properties of CPB with CaCl2 and NaCl antifreeze. This study investigated the effects of antifreeze (CaCl2 and NaCl) on the strength development of CPB curing in above-zero underground environments with a pre-cured at − 12 °C for 1 h. CPB samples with CaCl2 and NaCl antifreeze were prepared and cured under above-zero underground temperatures (2, 20, and 35 °C). Compressive strength tests were implemented after specific curing time (1, 3, 7, and 28 d). Moreover, microstructural analyses and monitoring experiments were performed. The strength of the sample with 15 g/L CaCl2 and NaCl decreased with curing at underground temperatures 20 °C for 1, 3, and 7 d, and increased at 28 d, which was attributed to the competition between the CaCl2 and NaCl antifreeze-induced strength enhancement, that is, increased hydration products, and strength weakening, that is, coarsened pore structure. The development of the CPB strength with the curing time depends on the concentrations of CaCl2 and NaCl and the above-zero underground environments. The findings elucidates on antifreeze CPB in engineering practice. [ABSTRACT FROM AUTHOR]

The use of pork obtained from intensively growing hybrid animals as the main raw material in meat processing, in particular sausage production, is accompanied by undesirable variability of consumer characteristics of sausage products and a decrease in the economic indicators of enterprise performance. The main technological disadvantages of processed pork are reduced water-binding capacity and significant loss of meat fluid, which in practice is usually compensated by the increased use of food additives and non-meat ingredients. The aim of the study was to assess the possibility of targeted improvement of the technological properties of minced pork using a proteolytic enzyme of animal origin. Model samples of minced meat were developed and cured for 24 hours at a temperature of 4 °C. The following control samples were used: minced meat with the addition of 2% edible salt and minced meat with the addition of 2% edible salt and 0.2% sodium bicarbonate. Moreover, 0.0001% chymotrypsin was added to the test samples containing similar curing ingredients. During electrophoretic study, in samples with the enzyme, an increase in low-molecular fractions (20 kDa, 15 kDa and lower) was observed, which indicated the manifestation of proteolytic activity of chymotrypsin in model systems. Enzymatic treatment led to an increase in pH and water-binding capacity. Cooking loss was reduced by 3 to 6 times, compared to Control 1. After cooking, histological studies of model systems showed that the test samples subjected to enzymatic treatment were characterized by a denser arrangement of structural elements, less pronounced cellular components of muscle tissue and the presence of glutin formed as a result of protein breakdown, filling the microcapillaries. Thus, the use of an enzyme preparation provides an opportunity for targeted improvement of the technological properties of pork obtained from intensively growing hybrid animals.

Sand production along with the oil/gas detrimentally affects the oil production rate, downhole & subsurface facilities. Mechanical equipment and various chemicals like epoxy resin, furan resin, phenolic resin, etc. are used in the industry to reduce or eliminate this problem. In the present study, a blend of organic and inorganic silicates are used to consolidate loose sand in the presence and absence of crude oil using a core flooding apparatus. The effects of chemical concentration, pH, curing temperature and time, and the presence of residual oil on the consolidation treatment results such as compressive strength and permeability retention, were investigated and optimized. FT-IR and FE-SEM characterization techniques were employed to investigate the interaction between the chemical molecules and the sand grains. The current binding agent exhibited a viscosity of less than 6 cP at room temperature, which facilitates efficient pumping of binding agent into the desired formation through the well bore. The developed mixture demonstrated consolidation properties across all pH conditions. Furthermore, during the experimental investigation, the curing time and temperature was carefully optimized at 12 h and 423.15K, respectively to achieve the highest compressive strength of 2021 psi while achieving the permeability retention of 64%. The current chemical system exhibited improved consolidation capacity and can be effectively utilized for sand consolidation treatment in high-temperature formations.