Decrease In Enthalpy Research Articles

Effects of molecular structure on the grafting of diaminobenzene sulfonic acid onto graphene oxide

Molecular grafting is an effective technique for introducing sulfo groups into materials such as graphene oxide (GO). Existing studies on the grafting molecules with sulfo groups onto GO have been empirical, and the analytical elucidation of this process remains insufficient. In this study, we experimentally and numerically investigated the adsorption and reduction reactions between GO and two types of diaminobenzene sulfonic acids (DBSAs), namely 2,4- and 2,5-DBSAs, that possess an equal number of functional groups but different coordination numbers. Composite films of GO and DBSA were prepared from a GO/DBSA solution using centrifugation and filtration. Initially, X-ray diffractometry was employed to confirm the intercalation of DBSAs between GO layers in GO/DBSA composite films. Subsequently, X-ray photoelectron spectroscopy and Fourier-transform infrared spectroscopy were performed; the results indicated that the bonding in GO to the oxygen functional group was replaced by the bonding to the amino group of DBSA; moreover, 2,5-DBSA was more reactive towards GO than 2,4-DBSA. To further investigate the reactivity differences, density functional theory calculations were performed. The decrease in enthalpy after the reaction of 2,5-DBSA was found to be higher than that of 2,4-DBSA, suggesting higher reactivity for 2,5-DBSA.

Synergistic effect of nitrocellulose coating on structural and reactivity stabilization of ammonium nitrate oxidizer

The present work aims to stabilize the room temperature allotropic transition of ammonium nitrate (AN) particles utilizing a microencapsulation technique, which involves solvent/non-solvent in which nitrocellulose (NC) has been employed as a coating agent. The SEM micrographs revealed distinct features of both pure AN and NC, contrasting with the irregular granular surface topography of the coated AN particles, demonstrating the adherence of NC on the AN surface. Structural analysis via infrared spectroscopy (IR) demonstrated a successful association of AN and NC, with slight shifts observed in IR bands indicating interfacial interactions. Powder X-ray Diffraction (PXRD) analysis further elucidated the structural changes induced by the coating process, revealing that the NC coating altered the crystallization pattern of its pure form. Thermal analysis demonstrates distinct profiles for pure and coated AN, for which the coated sample exhibits a temperature increase and an enthalpy decrease of the room temperature allotropic transition by 6 °C, and 36%, respectively. Furthermore, the presence of NC coating alters the intermolecular forces within the composite system, leading to a reduction in melting enthalpy of coated AN by ∼39% compared to pure AN. The thermal decomposition analysis shows a two-step thermolysis process for coated AN, with a significant increase in the released heat by about 78% accompanied by an increase in the activation barrier of NC and AN thermolysis, demonstrating a stabilized reactivity of the AN-NC particles. These findings highlight the synergistic effect of NC coating on AN particles, which contributed to a structural and reactive stabilization of both AN and NC, proving the potential application of NC-coated AN as a strategically advantageous oxidizer in composite solid propellant formulations.

The significant role of passive oxide layer on reactive metal combustion: insights into composite solid propellant with superior performance

ABSTRACT Passive oxide layer could expose a significant impact on reactive metal combustion. Boron and aluminum experience combustion enthalpy of 59.3 and 31.1 KJ/g and passive oxide layer of 200 and 7 nm, respectively. In this study, surface oxygen of born and aluminum particles (10 µm) was quantified via EDAX analysis. Boron and aluminum demonstrated surface oxygen content of 14.6 and 7.2 wt %, respectively. Reactive particles were integrated into ammonium perchlorate (AP) oxidizer. While boron demonstrated decrease in AP decomposition enthalpy by −14.8%; aluminum offered an increase in AP decomposition enthalpy by 60.8% using DSC. Whereas, aluminum oxide layer could be pealed out more effectively; boron passive oxide layer could melt with the evolution of an insulating barrier. Aluminum particles offered decrease in AP apparent activation energy by 68%, 105%, and 76% using Kissinger, Kissinger-Akahira-Sunose (KAS), and Flyn and Wall (FWO) models, respectively. Solid propellant formulations were developed; ballistic performance was assessed using small-scale rocket motor. Aluminum particles demonstrated stable combustion process with enhanced specific impulse and total pressure impulse compared with boron. Additionally, aluminum particles demonstrated stable burning with pressure exponent of 0.19 compared with 0.4 for boron particles.

Effect of AlN nanoparticle doping on thermophysical properties of nitrate via mechanical milling: Experimental studies and microscopic mechanisms

A compounding method based on ball milling was used to incorporate AlN into LiNO3 to effectively improve its thermal conductivity. The optimal doping ratio was determined to be 2 wt% with an increase in thermal conductivity of 112.09 % integrating the enthalpy decrease. From the perspective of molecular dynamics simulations, it is demonstrated that AlN achieves a better matching of vibrations with LiNO3 by changing its vibrational modes at the doping ratio of 2 wt% with the support of vibration density of states, overlapping energy and phonon participation ratio. When 2 wt% AlN was added, non-local vibrational modes of LiNO3 increased, which microscopically illustrated the intrinsic mechanism of 2 wt% as the optimal doping ratio. The radial distribution function was used to explain the microscopic mechanism behind the changes in the specific heat of LiNO3 concerning temperature. The reason why the enthalpy of LiNO3 would decrease after AlN added is that AlN can bind LiNO3 molecules on the surface, and LiNO3 is confined by stronger intermolecular forces, leading to a blockage of its phase change behavior. This study proposed a doping method that can uniformly disperse AlN and avoid crystallized water. It also provides a strategy for selecting the appropriate nanoaddictives for compositing in molten salts to enhance energy storage efficiency.

Changes in the structure and enzyme binding of starches during in vitro enzymatic hydrolysis using mammalian mucosal enzyme mixtures

Starches are hydrolyzed into monosaccharides by mucosal α-glucosidases in the human small intestine. However, there are few studies assessing the direct digestion of starch by these enzymes. The objective of this study was to investigate the changes in the structure and enzyme binding of starches during in vitro hydrolysis by mammalian mucosal enzymes. Waxy maize (WMS), normal maize (NMS), high-amylose maize (HAMS), waxy potato (WPS), and normal potato (NPS) starches were examined. The order of the digestion rate was different compared with other studies using a mixture of pancreatic α-amylase and amyloglucosidase. NPS was digested more than other starches. WPS was more digestible than WMS. Hydrolyzed starch from NPS, NMS, WPS, WMS, and HAMS after 24 h was 66.4, 64.2, 61.7, 58.7, and 46.2 %, respectively. Notably, a significant change in the morphology, reduced crystallinity, and a decrease in the melting enthalpy of the three starches (NPS, NMS, and WPS) after 24 h of hydrolysis were confirmed by microscopy, X-ray diffraction, and differential scanning calorimetry, respectively. The bound enzyme fraction of NPS, NMS, and WPS increased as hydrolysis progressed. In contrast, HAMS was most resistant to hydrolysis by mucosal α-glucosidases in terms of digestibility, changes in morphology, crystallinity, and thermal properties.

Mild steam treatment: Enhancing the rehydration performance of instant rice noodles by changing the physicochemical properties and gel structure of rice starch.

The "instant" quality of instant rice noodles is significantly affected by slow rehydration during cooking. This happens as a result of the native rice starch's low ability to gelatinize as well as the high shear and pressure utilized in industries during the widely used extrusion molding process. In order to address this issue, the rice flour was pretreated with mild steam (MS) technology. The results revealed that the rehydration qualities of the rice noodles that were extruded from the steam-treated flour significantly improved. There was a reduction of 25.5% in the rehydration time, from 443 to 330s. The MS-treated rice starch's peak viscosity increased to 4503 from 4044mPa/s. Decreases in gelatinization enthalpy (ΔH) and short-range ordering also suggest a reduction in difficulty in accomplishing starch gelatinization. Scanning electron microscopy studies showed particle aggregation increased as the treatment duration lasted longer. In conclusion, our findings indicate that we successfully addressed the issue of slow rehydration in instant rice noodles while presenting a novel approach for their manufacturing in the manufacturing sector.

Kinetics and thermodynamic stability of native and chemically modified acid invertase: Extracted from yellow pea (Lathyrus aphaca) Seedlings

In this work, an acid invertase isolated from Lathyrus aphaca seedlings is purified, and its thermal properties are investigated. Acid invertase was purified through salt fractionation, CM-cellulose, and Ultrogel ACA-44 chromatography. Using SDS-PAGE, the consistency of the isolated enzyme was verified. The enzyme weighs 29 kDa at the molecular level. Acid invertase functions best at a pH of 3.0 and a temperature of 45 °C. Activation energy of 29.5 kJ mol−1 and Km and Vmax values of 0.5 mM and 119.7 µmol. min−1. mg−1 of protein was found for the isolated enzyme. It was shown that the mercaptide-forming agent p-chloromercuribenzoic acid (PCMB; 0.5 mM) and the enzyme's activity were both modestly increased by Ca2+, Mn2+, and Mg2+ ions but inhibited by Hg2+, Cd2+, and Pb2+ ions. At elevated temperatures, the invertase exhibited an increase in thermostability due to an increase in activation entropies (∆Sº) and a decrease in activation enthalpies (∆Hº). The interactions between 4 M urea and α-chymotrypsin were tetraphasic, causing periodic increases and decreases in invertase activity. It also suggests a potential explanation for acid-invertase thermal inactivation at high temperatures. This enzyme might be a catabolite-resistant invertase to produce high-gravity ethanol or fructose syrup.

Dielectric barrier discharge cold plasma modifies the multiscale structure and functional properties of banana starch

Banana starch has attracted significant attention due to its abundant content of resistant starch. This study aims to compare the multiscale structure and functional properties of banana starch obtained from five cultivated varieties and investigate the impact of dielectric barrier discharge cold plasma (DBD) treatment on these starch characteristics. All five types of natural banana starch exhibited an elliptical and irregular shape, conforming to the CB crystal structure, with a bimodal distribution of branch chain lengths. The resistant starch content ranged from 88.9 % to 94.1 %. Variations in the amylose content, amylopectin branch chain length distribution, and structural characteristics resulted in differences in properties such as gelatinization behavior and sensitivity to DBD treatment. The DBD treatment inflicted surface damage on starch granules, reduced the amylose content, shortened the amylopectin branch chain length, and changed the relative crystallinity to varying degrees. The DBD treatment significantly increased starch solubility and light transmittance. Simultaneously, it resulted in a noteworthy decrease in peak viscosity and gelatinization enthalpy of starch paste. The in vitro digestibility test showed that 76.2 %–86.5 % of resistant starch was retained after DBD treatment. The DBD treatment renders banana starch with reduced viscosity, increased paste transparency, enhanced solubility, and broadens its potential application.

Beef tenderization without exacerbating the cooking loss: The way of enzymatic deamidation

Tenderization of beef using proteolytic enzymes often leads to high water loss due to harsh structural disruption. This study first verified the enzymatic deamidation (protein-glutaminase, PG) in softening grass-fed steak texture without exacerbating the cooking loss. PG deamidation at the deamidation degree (DD) of 5% (d5) or 7% (d7) significantly increased the tenderness and softened the texture whereas they negligibly affected the cooking loss. The muscle bundles were loosed while fibers were thickened probably as the result of charge induced myofibril dissociation (increased myofibril fraction index) and intermolecular repulsion. Compared to papain, the effect of PG deamidation on the water mobility was minor, though it was still seen a slight conversion of bound water into immobilized water in high DD steaks (d5 and d7). PG deamidation hardly hydrolyze individual proteins but partially altered the tertiary structure of muscle proteins, resulting in a slight decrease in denaturation enthalpies of muscle proteins including myosin, collagen and sarcoplasmic protein. These results demonstrated that PG deamidation appeared to be a novel and promising strategy in meat tenderization.

Microstructure and gas-solid hydrogen storage properties of La1-xCexY2Ni10.95Mn0.45 (x = 0 – 0.75) alloys

RE-Y-Ni-based superlattice alloys have been studied for their high hydrogen storage capacity and excellent activation properties. However, their practical applications in gas-solid hydrogen storage devices are limited by their low hydrogen absorption/desorption platform pressure and the occurrence of a double platform phenomenon. In this study, we investigated the phase structure and gas-solid hydrogen storage properties of La1−xCexY2Ni10.95Mn0.45 (x = 0, 0.15, 0.30, 0.45, 0.60, 0.75) alloys. As the Ce content increases, the content of Ce2Ni7 phase and the platform pressure also increase, while the hydrogen storage capacity and hydrogen desorption enthalpy decrease. When the Ce content increases to 0.45, the Gd2Co7 phase disappears and the LaNi5 phase appears, the hydrogen absorption/desorption platform of the alloy changes from a double platform to a single platform. However, the increase in Ce content leads to a higher amount of residual hydrogen during the dehydrogenation process, attributed to the increased content of the Ce2Ni7 phase. The La0.55Ce0.45Y2Ni10.95Mn0.45 alloy exhibits a hydrogen absorption capacity of 1.61 wt%, with a capacity retention of 97.89% after 100 cycles, and achieves a hydrogen desorption platform pressure of 0.23 MPa. These results indicate that this alloy demonstrates the best overall hydrogen storage performance, characterized by high platform pressure and hydrogen storage capacity.

Effects of different drying treatments on the structural, functional and in vitro digestive characteristics of isolated starch from tiger nut

Drying treatment can significantly increase the oil yield of tiger nuts, and the full utilization of starch by-products in tiger nut meal is an important aspect of improving its industrial value. Consequently, the effects of roasting, microwave and roasting treatments on the structure, functional properties and in vitro digestive characteristics of tiger nut starch were investigated. The results showed that compared to that of CS (untreated control starch), samples of BS (baked starch), MS (microwaved starch), and RS (roasted starch) showed deeper color, surface cracks, partial aggregation on the granules, and larger particle size. In addition, baking, microwave and roasting treatments all decreased the relative crystallinity and short-range ordering of the tiger nut starch, explaining the decrease in enthalpy in the DSC results, the increase in the stability of the freeze-thaw, the solubility and the swelling. From the rheological analysis of starch, it was found that the gel structure of tiger nut starch decreased after the aforementioned treatments. This indicates that the branched chain starch was damaged, which impacing the digestibility of the starch. Further in vitro digestion tests demonstrated that three drying treatments increased slow-digestible starch and resistant starch content. Among them, microwave drying treatment had a significant effect on the structural and functional properties of the isolated starch of tiger nut. This study aimed to provide theoretical guidance for the comeplete utilization of tiger nut starch.

Thermophysical properties of Cordyceps militaris change during the freezing process

This study focuses on determining the thermophysical parameters of Cordyceps militaris in the freezing stage of the freeze-drying process. When the temperature of Cordyceps militaris changed from an ambient temperature of 25°C to a freezing temperature of -45°C, the thermophysical parameters of Cordyceps militaris changed much. The study determined the initial freezing point temperature of Cordyceps militaris to be -0.6°C. At temperatures above the initial freezing point, the density (ρ) and specific heat (c) increase slightly as the temperature decreases. In contrast, thermal conductivity (k), thermal diffusivity (a), and enthalpy (h) decrease. However, at temperatures below the initial freezing point, when the temperature decreases, the density, specific heat, and enthalpy decrease while the coefficient of thermal conductivity and thermal diffusion increase. The results obtained from this study can be applied in calculating the heat and mass transfer during the freezing phase in the freeze-drying process of Cordyceps militaris.

Humidity-controlled heat treatment of fresh spinach noodles for color preservation and storage quality improvement

The high sensitivity to color browning during room-temperature storage was a significant factor in limiting the development of fresh spinach noodles (FSN). The practice of humidity-controlled heat treatment (HCHT) at varying temperatures, relative humidity, and time was carried out to limit enzyme activity and improve the quality of FSN. Results showed that HCHT could maximize the color preservation of fresh spinach noodle quality while effectively inactivating polyphenol oxidase and the yeasts, and mold count in FSN during storage was almost undetectable after mild conditions (80 °C). The hardness and chewiness of HCHT noodles were significantly increased, but the free sulfhydryl content was reduced. At 80 °C, 90 %, 5 min, protein structural aggregation was found in the microstructure of HCHT fresh spinach noodles. HCHT also caused partial gelatinization, as evidenced by the decrease in starch gelatinization enthalpy from 5.49 to 4.77 J/g, although the gelatinization degree of FSN was comparatively low.

Thermodynamic Properties of Seeds: A Review

Study of isotherms and thermodynamic properties become essential to understand the drying and imbibition mechanisms of seeds. Among post-harvest procedures of seeds, drying is widely known and used in order to assure quality and stability during storage and shelf life. Variation of moisture content through drying is important in order to understand the interaction between water molecules and the seed components, which is the key factor for correct drying and storage. Seed viability could be maintained during long periods owing to their glass structure, as a thermodynamic unstable state, with high viscosity. Thermodynamic properties were enthalpy (Amount of energy available to do work), entropy (Amount of energy present but it not available to do work) and gibbs free energy (Differential energy between the enthalpy and entropy). Thermodynamic properties of seed water determines the reaction kinetics during seed deterioration. Thermodynamic properties showed a critical upper limit, with tolerant species having higher values then susceptible species. In general the values of critical limits of the thermodynamic parameters decreased with increasing temperature. The differential enthalpy and entropy increased in seeds with period of storage and became asymptotic as the seed lost their viability. Thermodynamics properties increased with increase in temperature, indicating that drying and water absorption do not occur spontaneously it requires external energy. A radical drop in germination follows the trend of gibbs free energy increase and enthalpy decrease, indicating intensification of endergonic reaction. Hence, it is concluded that by using thermodynamic properties of seeds the seed quality can be determined without conducting the germination test in shortest period.

Pineapple Peel Flours: Drying Kinetics, Thermodynamic Properties, and Physicochemical Characterization

Pineapple is a widely cultivated, consumed, and processed fruit by the industry. However, only 22.5% of the whole fruit is used, which constitutes economic waste and environmental impact. The objective was to determine the drying kinetics and characterize the residual peel flours of two pineapple varieties at four drying temperatures. Jupi and Pérola pineapple peels were dried at temperatures of 50, 60, 70, and 80 °C in a thin layer. Ten mathematical models were adjusted to the experimental data to characterize the drying process. Fresh samples and flours were characterized according to their physicochemical properties (water content, ash, water activity, total sugars, reducers, pH, acidity, proteins, lipids, carbohydrates, and total energy value—TEV). The Midilli model was chosen because it best represents the drying process with high values of determination coefficients (R2) and low mean squared deviations (MSD), Chi-square (χ2), and estimated mean error (EME). The increase in temperature led to an increase in the effective diffusivity coefficient and consequent reduction in drying time. The activation energy obtained from the Arrhenius equation was 24.59 and 26.25 kJ/mol for Jupi and Pérola, respectively. Differences were reported in the enthalpy and entropy decrease with the increasing temperature, contrary to the Gibbs free energy. The flours produced had good characteristics for conservation, being acidic with low water content and low water activity. High levels of total and reducing sugars, carbohydrates, and total energy value were observed, in addition to good protein content.

Advanced design of bimetal sulfide/V2CTX MXene photothermal nanocomposites for integrated solar steam generation, electricity generation, and water purification

The utilization and conversion of solar energy is considered an environmentally friendly strategy to achieve global carbon peak and carbon neutrality. To synergistically alleviate freshwater and electricity scarcity, designing multifunctional photothermal composites that are highly efficient and stable is particularly important. Herein, a multifunctional Cu3BiS3@V2C/BF membrane with a bilayer structure has been developed, the top is Cu3BiS3@V2C-1 nanocomposite coating, and the bottom is porous BF membrane, the interface matching is achieved by coordination effect of calcium ions and carboxylate group. The Cu3BiS3@V2C-1/BF membrane can achieve a broadband absorption of ≈95.2 % in the full spectrum, benefitting from the near-infrared spectral compensation mechanism. Further, a high evaporation rate of 1.68 kg m−2 h−1 is achieved by the synergetic design of multistage photothermal conversion and the decrease in evaporation enthalpy. Moreover, the membrane has high solar desalination efficiency, electricity generation of 55 mV under one sun, and water purification performance, which profit from the unique sodiophilic property of V2CTx MXene, the enhanced photothermal catalysis and the abundant adsorption sites of Cu3BiS3@V2C-1 nanocomposite. Furthermore, the deep mechanism of photothermal conversion and photothermal catalytic is analyzed using first-principles calculation. This work is a promising approach to focus on multifunctional solar utilization in the future.

Understanding the improvement of sorghum starch acid hydrolysis modification by E-beam irradiation: A supramolecular structure perspective

To investigate the effect of E-beam irradiation (EBI) on acid-hydrolyzed starch, sorghum starch was pretreated with EBI (2, 4, and 8 kGy) and further hydrolyzed using hydrochloric acid (1 % and 6 % concentrations) in this study. EBI intensified acid hydrolysis corrosion on starch granule surfaces without inducing changes in the growth ring, FT-IR spectra, and crystal type (A-type). Also, EBI promoted starch degradation by acid hydrolysis, as evidenced by the R1047/1022 loss (1.071 to 1.027), the molecular weight decrease, and the chain length distribution shift (toward short A-chain). Moreover, this synergistic modification induced a starch enthalpy decrease (only 9.49 J/g) and crystallinity reduction (29.87 %), while solubility increase (34.27 %) and swelling power inhibition (only 7.65 g/g) were observed. Notably, starch digestibility was improved after synergistic modification. The obtained results broaden the processing depth of EBI in modified starch and highlight the promising application of acidolysis sorghum starch as a potential industrial starch.

Investigating the influence of CaCl2 induced surface gelatinization of red adzuki bean starch on its citric acid esterification modification: Structure–property related mechanism

This study prepared starch with different degrees of gelatinization (10 % and 30 %) by CaCl2, and further combined with citric acid at different concentrations (10 %, 20 %, and 30 %) for esterification. The results indicated that CaCl2 induced surface gelatinization and the esterification promoted its fragmentation. This synergistic modification induced depolymerization of starch chains and a decrease in molecular weight, although starch's Maltese cross, growth rings, and crystal type remained unchanged. Moreover, the synergistic modification induces a short-range ordered structure loss and the enthalpy decrease of starch, which induce starch pasting properties decrease and solubility increase. Furthermore, the introduction of ester groups by esterification increases the resistant starch content by limiting the binding sites for digestive enzymes. In conclusion, surface gelatinization can increase active reaction sites by disrupting the starch shell structure, and serves as a potential pretreatment to enhance the deep application of esterified starch in food and pharmaceutical fields.

Insights into Entropy Change of β2 Relaxation in Retraction of Uniaxially Stretched Polyimide Films

AbstractStretching has been extensively applied for decades in the production of polyimide (PI) materials with improved mechanical, electrical, and thermal properties. Meanwhile, a detailed understanding of the molecular motions during stretching is still limited. Herein, the thermomechanical behaviors of uniaxially stretched PI films prepared from 3,3′,4,4′‐biphenyl tetracarboxylic dianhydride (BPDA) and 2,2′‐bis (trifluoromethyl) benzidine (TFDB) are studied, and the possible molecular motions responsible for the sub‐glass transition temperature (Tg) stretchability and retraction after stretching are systematically investigated. Based on X‐ray diffraction and dynamic mechanical analysis, it is revealed that both the sub‐Tg stretchability and retraction correlates with β2 relaxation, which originates from the highly cooperative molecular motions of conformational rotations involving segmented BPDA units. A thermodynamic model is established and applied for the analysis of the retraction behaviors of stretched BPDA‐TFDB PI films. It is found that the increase of entropy under stretching plays a significant role in most retraction cases. However, as the stretching temperature increases, the α relaxation‐correlated large‐scale molecular motions emerge. Such motions partially counterbalance the conformational rotations of BPDA segments, leading to an enhanced contribution of enthalpy decrease during the retraction of BPDA‐TFDB PI films.

Numerical prediction of the solidification and melting of encapsulated nano‐enhanced phase change materials

AbstractThe thermal properties of Octadecane vary due to the addition of copper oxide (CuO) nanoparticles. The synthesis of two nano‐enhanced phase change material (NEPCM) required the implementation of the two‐step method, using Octadecane as the base phase change material and CuO nanoparticles at 2.5 and 5.0 wt%. The experimental characterization determined the specific heat capacity, and thermal conductivity of the NEPCMs solid phase, including phase change enthalpy and temperature. These experimental results were then utilized for computational simulation of the thermal charging (solidification) and discharging (melting) processes of NEPCMs within a spherical enclosure, employing the ANSYS/Fluent software. The incorporation of CuO nanoparticles led to an increase in thermal conductivity while causing a decrease in specific heat capacity, enthalpy, and phase change temperature of Octadecane. The computational results revealed a reduction in the melting period and an improvement in the solidification of both NEPCMs. In terms of melting, the convective heat transfer coefficient increased by approximately 27.4% and 3.2% for the NEPCM at 2.5 and 5.0 wt% CuO, respectively. During the solidification process, the overall heat transfer coefficient experienced a significant increase of 43.8% and 59.8% for the NEPCM at 2.5 and 5.0 wt%, respectively.