Resin Ratio Research Articles

Mechanical analysis of polyester resin using digital image correlation and finite element method

The primary objective of this study is to perform a comprehensive mechanical analysis of unsaturated polyester (UP) resin under unidirectional tensile loading. The Digital Image Correlation (DIC) technique was employed to accurately determine the mechanical properties of the material, with full-field strain measurements used to extract both transverse and longitudinal strains through virtual extensometers. This approach facilitated the precise calculation of the Poisson’s ratio of the UP resin. The results obtained via DIC demonstrated strong correlation with the experimental data obtained through the machine’s control software, particularly in capturing vertical displacement and longitudinal strain with high precision. The Poisson’s ratio was found to be 0.46. To further validate the DIC findings, Finite Element Analysis (FEA) was conducted. The FEA results aligned closely with the experimental data, confirming the reliability and accuracy of the DIC method in this context. The values of Young’s modulus determined from experimental tests and FEA data were 3620.02 MPa and 3598 MPa, respectively, with a percentage error of only 0.61%.

Benefits of Environmentally Friendly Plaster on Mechanical Properties When Combined with Polyester Resin and Hardener Are Examined under Compression and Tension.

Recently, plaster has gained increasing attention as a mechanical and environmentally friendly option and is an effective alternative to traditional cement products. Additionally, polyester has an effective impact on the mechanical properties of materials, in addition to being one of the most environmentally friendly materials. However, studies are still ongoing to reach the best ratios of polyester resin, polyester hardener, and gypsum plaster that can improve mechanical properties. This research aims to investigate the impact of these components at various ratios (30%, 45%, and 60%) of gypsum plaster weight on the mechanical properties of plaster material. This study is carried out by conducting compression and tensile tests for three ratios, which are considered among the most important mechanical tests according to their applications. In addition, the environmental emissions resulting from the three different ratios of plaster are evaluated to determine their environmental impact. This study found that the largest ratio (30%) was the most effective from an economic and mechanical point of view, while achieving lower carbon emissions compared to the other ratios, which enhances the trend towards achieving the environmental goals of the Kingdom of Saudi Arabia's Vision 2030 to reach zero emissions. This study is highly significant both in terms of scientific research and practical application across a range of industries, since it integrates the enhancement of material performance with the achievement of environmental sustainability requirements.

The impact of altering the molar ratio on formaldehyde content and the physical and mechanical properties of MDF panels

This study aimed to evaluate the influence of the molar ratio of urea-formaldehyde resin (UF) on formaldehyde content and the physical and mechanical properties of MDF panels. The goal was to determine the optimal composition, i.e. the one that exhibits the lowest formaldehyde content without compromising the properties. To that end, there were five treatments. They were characterized by five F:U molar ratios (0.9:1; 1.0:1; 1.1:1; 1.2:1; and 1.3:1). The panels had a nominal density of 750 kg.m−3, dimensions of 40 × 40 × 1.5 cm, 12% resin, 1% paraffin. They were produced with a pressing cycle with a temperature of 170 °C and pressure of 3.6 MPa per 10 min. The physical-mechanical properties of the panels and the formaldehyde content were determined and evaluated following the NBR 15316-2 (2019) standard. Results showed that the formaldehyde content was lower for panels produced with resin molar ratios of 0.9:1, 1.0:1, and 1.1:1, classified as E1. Panels with a resin molar ratio of 1.2:1 were classified as E2. The molar ratio of 1.3:1 exceeded the limits of the standard. Panels with resin molar ratios of 1.1:1, 1.2:1, and 1.3:1 met the standard requirements for all physical-mechanical properties of non-structural MDF for use in dry conditions. These results indicate that the most suitable UF resin molar ratio for producing MDF panels is 1.1:1. This radio provides low formaldehyde content and technological properties compatible with the reference standard.

CO2-Induced In-Situ Targeted Precipitation of Asphaltene in Heavy Oil Reservoirs: Balancing Formation Gas Channeling Regulation and Wellbore Asphaltene Blockage Prevention

Summary To investigate the mechanisms of the asphaltene precipitation in oil caused by CO2, the sandstone core oil displacement experiments and asphaltene structure observation experiments are designed in this work. The oil displacement experiments create CO2 flooding conditions under different pressures in heavy oil reservoirs and analyze the produced oil components and precipitated asphaltene proportions. Meanwhile, nuclear magnetic resonance (NMR) analysis is conducted on the sandstone cores to discuss the precipitation characteristics of asphaltene in the reservoir pores. The observation experiments analyze the microstructure of precipitated asphaltene after interactions between oil and CO2. The results show that the increasing pressure promotes the precipitation of asphaltene from oil by enhancing the dissolution and component extraction of CO2 in oil, which reduces oil viscosity and promotes reservoir development efficiency. This process also leads to an increase in CO2 sequestration in the reservoir. However, the precipitated asphaltene reduces reservoir permeability, hindering the optimization of the oil recovery rate. During the process of increasing pressure, the rate of increase in oil recovery decreases. In reservoirs containing oil with high asphaltene proportion, the oil recovery rate even decreases under high pressure. Additionally, in-situ targeted precipitation and retention of asphaltenes in large pores can reduce the distribution differences of pores with different sizes in the reservoir, weakening the above negative effects and enhancing oil recovery by regulating gas channeling. Moreover, the ratio of resin in oil affects the asphaltene precipitation form, and CO2 can promote the association of asphaltenes by weakening the steric stabilization effect of resin on asphaltene in oil, which makes the microstructure of precipitated asphaltenes dense and regular and promotes asphaltene precipitation and oil recovery increasing. This work aims to verify the advantages of CO2-induced asphaltene precipitation in improving the efficient and environmentally friendly development of heavy oil reservoirs, while exploring the significance of CO2 flooding in promoting carbon sequestration.

Research on the diffusion plugging mechanism of flowing water grouting slurry in karst pipelines

Among the many adverse geological disasters, the surge water disaster in karst areas causes the greatest loss to underground engineering construction, so it is necessary to carry out relevant research on the management of surge water disaster in karst pipelines. This study presents the creation of an oily epoxy resin magnetic convergence grouting material (OEMS) specifically developed to prevent water infiltration in pipelines. A self-designed visual karst pipeline grouting simulation system was used to conduct an experimental study on the diffusion and plugging behavior of magnetic slurry grouting. A model was constructed to simulate the migration of a magnetic slurry in water inrush circumstances. The model is based on the theory of slurry diffusion and the concept of magnetic adsorption. The results suggest that:(i) The best performance in grouting sealing is achieved when the ratio of new OEMS epoxy resin A liquid to B liquid is 2:1, and the blending ratio of flyash and Fe3O4 powder falls between 25 and 55%. (ii) The primary and secondary correlations among the parameters that affect the rate of change in flow rate, plugging pressure, and slurry retention rate are as follows: Hydrodynamic velocity has the greatest correlation, followed by plugging length, Fe3O4 power ratio, and flyash mixture ratio. (iii) The validity of the model is verified by comparing empirical observations with calculated theoretical values.

Wear Performance Evaluation of Polymer Overlays on Engine Bearings.

Modern engine bearing materials encounter the challenge of functioning under conditions of mixed lubrication, low viscosity oils, downsizing, start-stop engines, potentially leading to metal-to-metal contact and, subsequently, premature bearing failure. In this work, two types of polymer overlays were applied to the bearing surface to compensate for extreme conditions, such as excessive loads and mixed lubrication. Two different polymer overlays, created through a curing process on a conventional engine bearing surface with an approximate thickness of 13 µm, were investigated for their friction and wear resistances under a 30 N load using a pin-on-disc setup. The results indicate that the newly developed polymer overlay (NDP, PAI-based coating) surface has a coefficient of friction (COF) of 0.155 and a wear volume loss of 0.010 cm3. In contrast, the currently used polymer overlay (CPO) in this field shows higher values with a COF of 0.378 and a wear volume loss of 0.024 cm3, which is significantly greater than that of the NDP. It was found that, in addition to accurately selecting the ratios of solid lubricants, polymer resins, and wear-resistant hard particle additives (metal powders, metal oxides, carbides, etc.) within the polymer coating, the effective presence of a transfer film providing low friction on the counter surface also played a crucial role.

The impact of ecological aging on the mechanical performance of jute-banana fibre phenol-formaldehyde hybrid composites

Natural fiber composites provide an environmentally favorable and sustainable alternative to traditional materials, greatly reducing environmental impact. Aging tests are required to evaluate the long-term mechanical performance and durability of these composites under varied situations, ensuring their dependability and safety over time. This study investigates the effects of ecological aging on jute-banana fiber reinforced phenol-formaldehyde (JBP-F) composites. The experiment involved fabricating JBP-F composites using jute and banana fibers with varying weight ratios (60:40, 50:50, 40:60, 30:70) and subjecting them to various aging tests like long-time water resistance, accelerated water resistance, thermal aging, hydrothermal aging, soil burial test, and accelerated weathering test. The result showed that the composite with a 50:50 jute-banana fiber to resin ratio (JBP-F50) outperformed the other compositions examined in terms of aging resistance. This balanced ratio likely optimized fiber-matrix interaction, leading to superior strength and water resistance. Higher fiber content composites (like JBP-F60) absorbed more water due to weaker bonding, while lower fiber content (JBP-F30) suffered more in high temperatures. All composites experienced strength loss during thermal and hydrothermal aging due to heat and moisture cycles. JBP-F50 again showed the least degradation, possibly due to the resin’s ability to recover. In soil burial tests, biodegradation impacted strength, with higher fiber content composites (JBP-F60) degrading more. Finally, weathering tests revealed some surface deterioration due to UV radiation. However, the resin offered protection, with JBP-F30 (higher resin content) experiencing the most weight loss.JBP-F50, with its balanced fiber-resin ratio, demonstrated the best resistance to various environmental stresses, making it a promising option for sustainable composite applications.

Research on the wear resistance and impact resistance of modified rubberized concrete

Rubber can improve the ductility and durability of concrete and reduce compressive strength. Tests were conducted to investigate the mechanical properties, wear resistance, and impact resistance of modified rubberized concrete (MRC) by mixing basalt fibers (BF), curing agent, and epoxy resin mixture. The results showed that the epoxy polymer improved the flowability of the rubberized concrete. The BF changed the failure mode of the rubberized concrete and enhanced the mechanical properties. When the curing agent-epoxy resin ratio was 4:8, the wear rate of BF6E8C4 after 120 times was 4.59 kg/m2, which was 70.02% and 3.77% less than that of BF2E8C4 and BF4E8C4. The impact strength of BF6E8C4 was increased by 256% and 409% compared with the BF2E8C4 and BF4E8C4, respectively. By analyzing the mechanism of the synergistic modification of BF and epoxy polymer, it was found that the synergistic work of BF and epoxy polymer could make the internal structure of concrete denser. At last, the wear damage and impact damage models of MRC were established, and the coefficient of determination exceeded 0.92.

Synthesis of a water‐soluble high hydroxymethyl content phenolic resin crosslinker and the associated polyacrylamide weak gel property investigation

AbstractAs an in‐depth profile control agent, water‐soluble phenolic resin crosslinking polyacrylamide weak gel has been widely used in the middle and high water cut stage of water flooding reservoir. In this study, the phenolic resin was synthesized by two‐step alkali catalysis. Factors influencing the synthesis of phenolic resin, including the molar ratio of phenol and formaldehyde, catalyst types, reaction time, were investigated with hydroxylmethyl and aldehyde content as the criterion. When the molar ratio of phenolic resin was 1:2 and NaOH was catalyst, at 80°C for 4 h, the phenolic resin had the highest hydroxymethyl content (49.37%) and the lowest free aldehyde content (2.95%). Weak gel was formed by the reaction of LT002‐polyacrylamide with phenolic resin. Taking the gelation time and strength as criteria, the factors influencing the crosslinking property, including hydroxymethyl content, crosslinker addition, and polyacrylamide concentration were investigated respectively. Under optimal formulation, the property investigation shows that the hydroxymethyl group in the phenolic resin can be crosslinked with the amide group in polyacrylamide, the gelation time is long (50–60 h), and the gelation strength is larger than 5 × 104 mPa s, which is conductive to the plugging of deep oil layers. When the permeability was 5061 × 10−3 μm2, the plugging rate was 72.73%.

Performance of optimized composition of epoxy resin adhesive used in High Friction Surface Treatment

The High Friction Surface Treatment (HFST) paving technique is widely employed in engineering practices globally, serving to enhance the long-term anti-skid performance of pavements. However, there still exist significant gaps in research regarding the modified and optimized composition and corresponding content of the polymer binding materials used in HFST, as well as the performance of the pavements laid with modified and optimized blended aggregates during service. To address these issues, this research first modified and optimized the composition ratio of traditional epoxy resin materials. Subsequently, a toughened, high-flow epoxy bonding system suitable for the maintenance of concrete pavements was prepared. Additionally, the study explored the bonding performance of this system with both the cement base surface and aggregates. The results established that the optimal ratio range for the modified epoxy adhesive system is E51 epoxy resin to curing agent to toughening agent to diluent in the proportions of 100: 30–35: 20–30: 5. The experimental group used a high-flow epoxy resin adhesive ratio of E51 epoxy resin: curing agent: toughener: diluent = 100:30:20:5. For control group 1, the ratio of epoxy resin adhesive was E51 epoxy resin: curing agent = 100:30, and for control group 2, the ratio was E44 epoxy resin: curing agent = 1:1. Compared with control groups 1 and 2, the modified epoxy system with the cement base demonstrated a 149 % increase in average pull-off strength and an 18 % increase in average shear strength. Similarly, in comparison with control groups 1 and 2, the modified epoxy system with aggregates exhibited a 174 % increase in average pull-off strength and a 541 % increase in average shear strength. Based on the pull-off and shear test results, it was ultimately determined that the dosage of modified epoxy binder for HFST mixtures should be controlled at 1.0–1.2 kg/m2, and the dosage of aggregate should be controlled at 3.3–4.3 kg/m2. These findings provide valuable insights into optimizing HFST pavement compositions for improved performance and longevity.

Impact of different matrix systems on mechanical, thermal, and electrical properties of carbon fiber reinforced epoxy resin matrix composites

AbstractCarbon fiber reinforced epoxy resin matrix composite is one of the most important composite materials in the world. Many researchers have conducted a lot of research on epoxy resin matrix systems in recent years, mainly to improve the problem with the short curing time of the matrix system and epoxy resin's high viscosity. The final aim is to enhance various aspects of composites' performance and optimize the production process. A new type of water dispersed epoxy resin matrix system is investigated in this paper and the target is to optimize the mechanical, thermal, and electrical performances of the composites with the water dispersed epoxy resin matrix by varying different doping particles and different resin/catalyst ratios. Through a series of experiments, it is evident that varying the ratio of resin to catalyst in the matrix system will not significantly improve the mechanical as well as thermal properties of the composites. However, increasing the amount of catalyst in the matrix system can greatly improve the electrical properties of its composite samples. In addition to this, the addition of doping particles to the matrix systems has the effect of slightly enhancing the tensile modulus, thermal conductivity, and electrical conductivity of their composites.Highlights A new water‐dispersed epoxy resin matrix system improves processing technology. Increasing amount of catalyst in the matrix system improves electrical resistivity. Adding particles to matrix systems has a slight effect on different properties.

Multi-frequency composite wearable antenna for wireless communications

This paper proposes a multi-band composite wearable antenna for wireless communication, which uses a monopole structure as the radiating body and achieves multi-band characteristics through slit-loading and multi-branching methods. A polymer composite substrate with high dielectric constant and low dielectric loss was prepared using in situ polymerization, and the optimal dielectric constant and loss angle tangent were obtained by controlling the coating ratio of melamine formaldehyde resin to carbon nanotubes (MWCNTs) and the filler doping rate to achieve miniaturization of the antenna. Comparative experimental results show that the obtained composites have high flexibility and good dielectric properties. The antenna operates in the frequency bands of 2.21–2.52 GHz, 3.07–3.87 GHz, and 4.36–6.03 GHz, which cover the frequency bands of WLAN and WiMAX and 5G applications. The antenna was fabricated and tested, and its performance roughly matched the simulation results. Meanwhile, the antenna has passed the SAR safety test and maintained a stable performance under different curvatures, so it has potential applications in the wireless communication system.

Effects of Chemical Composition and Cross-Linking Degree on the Thermo-Mechanical Properties of Bio-Based Thermosetting Resins: A Molecular Dynamics Simulation Study.

Bio-based epoxy resins have received significant attention in terms of concerns regarding carbon emission. Epoxidized soybean oil (ESO) derived from sustainable feedstock has been widely used to blend with traditional diglycidyl ether of bisphenol-A (DGEBA) to replace some of the petroleum-based components. In this work, molecular dynamics (MD) simulations were applied to track the network formation and predict the performance of methyl hexahydrophthalic anhydride (MHHPA)-cured ESO/DGEBA blend systems. The effects of ESO content and cross-linking degree on the mass density, volumetric shrinkage, glass transition temperature (Tg), coefficient of thermal expansion (CTE), Young's modulus, yield strength, and Poisson's ratio of the epoxy resin were systematically investigated. The results show that systems with high ESO content achieve gelation at low cross-linking degree. The Tg value, Young's modulus, and yield strength increase with the increase in cross-linking degree, but the CTE at the glassy state and Poisson's ratio decrease. The comparison results between the simulated and experimental data demonstrated that the MD simulations can accurately predict the thermal and mechanical properties of ESO-based thermosets. This study gains insight into the variation in thermo-mechanical properties of anhydride-cured ESO/DGEBA-based epoxy resins during the cross-linking process and provides a rational strategy for optimizing bio-based epoxy resins.

Fabrication and Application of Grinding Wheels with Soft and Hard Composite Structures for Silicon Carbide Substrate Precision Processing.

In silicon carbide processing, the surface and subsurface damage caused by fixed abrasive grinding significantly affects the allowance of the next polishing process. A novel grinding wheel with a soft and hard composite structure was fabricated for the ultra-precision processing of SiC substrates, and the grinding performance of the grinding wheel was assessed in this study. Different types of gels, heating temperatures, and composition ratios were used to fabricate the grinding wheel. The grinding performance of the grinding wheel was investigated based on the surface integrity and subsurface damage of SiC substrates. The results showed that the grinding wheel with a soft and hard composite structure was successfully fabricated using freeze-dried gel with a heating temperature of 110 °C, and the component ratio of resin to gel was 4:6. A smooth SiC substrate surface with almost no cracks was obtained after processing with the grinding wheel. The abrasive exposure height was controlled by manipulating the type and ratio of the gel. Furthermore, the cutting depth in nanoscale could be achieved by controlling the abrasive exposure height. Therefore, the fabrication and application of the grinding wheels with soft and hard composite structures is important for the ultra-precision processing of large-size SiC substrates.

Proportioning optimization of transparent rock-like specimens with different fracture structures

Clarifying the principles of proportioning optimization for brittle transparent rock-like specimens with differential fracture structures is crucial for the visualization study of the internal fracture and seepage evolution mechanisms in rock masses. This study, utilizing orthogonal experimental methods, uncovers the influence mechanisms, extents, and patterns by which the ratios of resin, hardener, and accelerator, along with the freezing duration, impact the mechanical characteristics of transparent rock-like specimens. Notably, it was observed that as the accelerator ratio and freezing time are increased, there’s a general decline in the uniaxial compressive strength, tensile strength, and elastic modulus of the specimens. In contrast, an increase in the hardener ratio initially leads to an enhancement in these mechanical properties, followed by a subsequent decrease. Under uniaxial compressive loading, the specimens exhibit four typical modes of failure: bursting failure, splitting failure, single inclined plane failure, and bulging failure. As the hardener and accelerator ratios increase, the mode of failure gradually shifts from bulging to bursting, with freezing time having a minor overall impact on the evolution of failure modes. The study proposes a method for inducing random three-dimensional closed fractures within the specimens and further clarifies the principles for optimizing the proportions of specimens with different fracture structures, such as intact, embedded regular, and random three-dimensional fractures. This research facilitates the in-depth application of transparent rock-like materials in various scenarios and provides theoretical guidance and technical support for visualizing the evolution of fracture and seepage characteristics within the fractured rock mass.

Preparation and performance analysis of polyethylene glycol/epoxy resin composite phase change material

It is crucial for their widespread application to develop phase change materials (PCMs) that can be mass-produced and possess high thermal storage capacity and stability. This study uses polyethylene glycol (PEG) as the phase change material and epoxy resin as the matrix to prepare polyethylene glycol/epoxy resin composite phase change materials (EPPCM) by blending and analyzing the effects of PEG's molecular weight and content on EPPCM's performance. The results indicate that PEG and epoxy resin are physically blended without chemical reaction. When the molecular weight of PEG is fixed, the larger the content of PEG, the higher the crystallinity, phase change enthalpy value, and phase change temperature of EPPCM, and the weaker the thermal cyclic stability and mechanical properties. When the content of PEG is fixed, the larger the molecular weight of PEG, the higher the crystallinity, phase change enthalpy value, and phase change temperature of EPPCM, the stronger the thermal cyclic stability, and the weaker the mechanical properties. Using PEG-10000 as the PCM with a PEG to epoxy resin ratio of 1:2.5, the EPPCM shows a phase change exothermic temperature range of 33.4 °C to 45.7 °C, an endothermic temperature range of 54.3 °C to 65.4 °C, a phase change enthalpy of 130.0 J/g, and only 1.56 % mass loss after 30 phase change cycles.

Preparation and properties optimization of CeO2–Y2O3 Co-stabilized zirconia via vat photopolymerization

Employed ubiquitously in oral restorations, zirconia-based bioceramics face challenges with low-temperature degradation (LTD) in the tetragonal phase (t-ZrO2) within oral environments. In order to improve the resistance of ZrO2 ceramics to LTD, this study utilized vat photopolymerization technology to prepare 7Ce3Y–ZrO2 (7 mol% CeO2 and 3 mol% Y2O3). By adjusting the dispersant content and photosensitive resin ratio enabled the attainment of a 63.5 μm curing depth with a 400 mJ/cm2 exposure, meeting the requirements for vat photopolymerization printing. After sintering at 1550 °C, these ceramics shown a relative density of 97.84 % and an impressive flexural strength of 503.1 MPa. Accelerated LTD tests were conducted to assess LTD-resistance, revealing no degradation in mechanical properties or evidence of tetragonal to monoclinic phase transitions. This stability is credited to the cerium ions' efficacy in hindering oxygen vacancy formation and subsequent aging within the ZrO2. This study affirms that CeO2–Y2O3 co-stabilized ZrO2 ceramics prepared using vat photopolymerization technology exhibit outstanding properties and resistance to LTD, showcasing significant potential in the field of oral restoration.

Improved purification of cyclotron [68Ga]GaCl3 for the production of 68Ga radiopharmaceuticals

IntroductionIncreased demand for NetSpot and Illuccix as requirement to receive the respective Lutathera and Pluvicto radiotherapies, and monitor subsequent response to treatment, have reinforced the need to develop alternative ways of producing gallium-68 (68Ga). Building on our efforts to produce 68Ga in a liquid target on a GE PETtrace, the goal of this work is to modify the current GE Gallium Chloride cassette using the FASTLab 2 synthesis module to produce [68Ga]GaCl3 equivalent to a 1.85 GBq generator and demonstrate compatibility with FDA-approved kits for production of 68Ga-labeled radiopharmaceuticals. Methods68Ga was produced in a liquid target via the 68Zn(p,n)68Ga reaction. 68Ga was loaded onto various sizes of ZR resins (ZR Load, 0.3 mL, 1 mL, or 2 mL). The loading efficiency was determined using a dose calibrator. After washing with HNO3, 1.75 M HCl was used to elute the ZR Load resin through various sizes of a second ZR resin (ZR CG, 0 mL, 2 mL, 4 mL). Using 0.5 mL fractions, the elution profile was determined. Compatibility of the [68Ga]GaCl3 with NetSpot and Illuccix kits was investigated. Radiochemical purity (RCP) and 4 h stability were determined using radioTLC and radioHPLC. Using a modified [68Ga]GaCl3 cassette and new FASTLab program, 6 validation preparations were conducted using NetSpot and Illuccix kits for which RCP, stability, sterility and suitability were determined. Dual irradiation of 2 liquid targets was also performed, which was used to simultaneously prepare 1 NetSpot and 2 Illuccix kits by diluting the required activity with 0.1 M HCl. ResultsThe commercially available GE Cassette gave low RCP using commercial FDA kits. To optimize this, the loading efficiency onto ZR Load and the ratio of ZR resin used to load the initial activity and subsequent elution were explored. When using a 2:4 ratio of ZR Load to ZR CG, 97.89 % RCP was observed when a 3.8 mL [68Ga]GaCl3 solution was used. For Dotatate validation, 0.55 mL of buffer was added to 4.2 mL of [68Ga]GaCl3 which gave 1.35 GBq of formulated product. For Illuccix validation, [68Ga]GaCl3 was added to 2.5 mL of buffer which gave 1.52 GBq of [68Ga]Ga-PSMA-11. Formulated products passed package insert quality control (QC) requirements. When dual target irradiations were performed, 2.84 GBq was delivered to an external vial and used to label 1 NetSpot and 2 Illuccix kits simultaneously, and each kit also met or exceeded established QC criteria. ConclusionMethods are reported for using cyclotron-produced 68Ga from a liquid target in conjunction with FDA-approved NetSpot and Illucix kits. By employing a 2 mL ZR Load resin with a 4 mL ZR CG resin, adequate resolution between residual 68Zn and desired 68Ga was achieved. By modifying the FASTLab procedure to retain the final 2.5 mL of eluate from the ZR CG resin, [68Ga]GaCl3 equivalent to a new 1.85 GBq generator was obtained. This was suitable for labeling NetSpot and Illucix kits, resulting in high incorporation of 68Ga (RCP >95 %), which has not previously been demonstrated. Delivering [68Ga]GaCl3 into an external vial and diluting with 0.1 M HCl makes it possible to prepare multiple kits simultaneously. These new procedures should facilitate use of cyclotron-produced [68Ga]GaCl3 for clinical production going.

Preparation and decolorization of sapindus mukurossi extract and its application in sebum-control shampoos

BackgroundSapindus mukurossi extract (SME) is a kind of natural surface active ingredient with potential applications in cleansing products. However, the polyphenols and pigments contained in the extract may cause color browning of the products during storage especially at elevated temperatures, affecting its high level addition in the products. ObjectiveTo explore a decolorization process suitable for industrialization realize the high level addition of SME and explore the potential of SME in the field of controlling sebum esters. Materials and MethodsSME was prepared by adsorbing polyphenols on the D301 resin and oxidation decoloring oxidation. Investigated its sebum-control efficacy by SZ95 model and clinical study. ResultsThe results demonstrate that the D301 resin displays the best adsorption selectivity for polyphenols in SME, and the polyphenol adsorption ratio of D301 resin (5 wt%) can reach 83.6%; The optimal decolorization conditions are pH= 7.8, temperature 73 ℃ and decolorization time 5.7 h when H2O2 content is 6%, The prepared SME shows no obvious changes in color and retain stable during the high temperature (50 °C) test period of 28 days. 4 μg/mL of SME decreases the lipid synthesis of SZ95 cells by 24.8%. The clinic efficacy of the shampoo containing 10% SME (by dry extract weigh) is further evaluated. No significant changes in the skin moisture content and transepidermal water loss (TEWL) are observed within four weeks after using the product, while the scalp sebum level is significantly reduced. ConclusionIn this study, we prepared a light-colored, highly stable SME, enabled its high-level addition in cleansing and care products and found its sebum-control efficacy.

Low-temperature degradation of waste epoxy resin polymer improved by swelling-assisted pyrolysis

The disposal of waste epoxy resin matrix composite becomes an urgent issue, and pyrolysis is an effective method to decompose the epoxy resin polymer, but the high operating temperature hinders its application. In this study, a swelling-assisted pyrolysis method was proposed for the low-temperature decomposition of epoxy resin. It was found that the degradation ratio of epoxy resin increased from 59.13 % to 79.10 % at 300 °C after the swelling treatment with acetic acid. Compared with traditional pyrolysis, the cracking of epoxy resin was promoted in the swelling-assisted pyrolysis, increasing the yields of pyrolysis gas and oil, as well as enriching the light components in pyrolysis oil and raising the graphite degree of pyrolysis char. Following the characterizations and reactive force field molecular dynamics (ReaxFF-MD) simulation, the key mechanisms of swelling-assisted pyrolysis were determined as the interaction of the enhanced heat transfer and the accelerated ring-open reactions. After the swelling treatment, epoxy resin became porous, improving the heat transfer in the pyrolysis process. Meanwhile, abundant O radicals were generated with the decomposition of acetic acid, accelerating the ring-open reactions of benzene rings. The results could provide promising guidance for the pyrolysis recovery of epoxy resin matrix composites towards the circular economy.