Lower Mold Research Articles

A Study on Improving the Shape Error of the Lower Mold of Free-Form Concrete Panels Using Magnetic Force

A Study on Improving the Shape Error of the Lower Mold of Free-Form Concrete Panels Using Magnetic Force

Analysis of effect on temperature field of tire curing process by initial temperatures and condensate discharging

To improve the heat transfer efficiency and temperature distribution uniformity of steam-heating vulcanization processes, a 3D simulation model was established by Solidworks and transient simulation studies were carried out by Fluent 2021 R1. The effects of four initial tire temperatures and five condensate discharging schemes on the heat transfer efficiency and temperature distribution uniformity were investigated. The study finds that: (1) At the end of the stage of filling the capsule with high-temperature and high-pressure steam, the temperature of the lower mold sidewall is 152.08 °C which is significantly higher than that of the lower mold bead with 128.03 °C, the lower mold shoulder with 115.00 °C, and the lower mold crown with 109.57 °C. (2) With the initial tire temperature increasing from 25 °C to 55 °C, the final temperatures at the lower mold crown and the upper mold sidewall are increased by 12.00 °C and 2.27 °C, respectively, indicating that the increase in the initial temperature helps to raise the temperature at difficult vulcanization locations of the tire. (3) It is recommended to carry out condensate discharging when the volume fraction of condensate at the lower mold sidewall is 0.2 %∼0.3 %, which improves the temperature uniformity in the steam-heating vulcanization process.

РОДОВОЙ СОСТАВ И АГРЕССИВНОСТЬ ГРИБНЫХ БОЛЕЗНЕЙ У ОДНОЛЕТНИХ ЦВЕТОЧНЫХ КУЛЬТУР

In the context of the development of the agro-industrial complex and the replacement of imported plant material in the Russian Federation, the development of methods and technologies for the prevention and control of diseases and pests is a priority area of agrarian science. Fungal diseases cause great damage to both vegetable and ornamental crops. Some of the most harmful phytopathogens are fungi of the genus Fusarium (Fusarium Link). The objective of the study is to identify and determine the aggressiveness of the pathogenic mycobiota complex present on annual flowering plants of the Lamiaceae Bromhead family. During immunological studies on plants, fungal pathogens from the genera Alternaria Nees, Fusarium Link, some species of Pythium spp. and representatives of lower mold fungi Penicillium Link, Mucor Fresen were identified. Based on this, a collection of the most common pathogens from the genera Alternaria (5 samples) and Fusarium (10 samples) was created. When testing the selected samples using the method of L.M. Sokolova, the strains of alternariosis did not show high pathogenicity, the damage score of the tested material was from 0.5 to 1.0. When testing the strains of fusarium, the damage score varied from 1.0 to 4.0. Based on this, only one aggressive strain FAK-7 was selected, which had a damage score of 4.0 for the tested material. This pathogenic strain was isolated from the root system of the snapdragon selection line A-5-1. This strain will be involved in the selection process to work on the resistance of snapdragon lines and varieties to root rot.

The effect of maltodextrin edible coating containing pyracantha extract and potassium nano-carbonate on secondary metabolites, antioxidant capacity and microbiological properties of grape during cold storage

This study aimed to investigate the postharvest application of edible coating of maltodextrin containing potassium nanoparticles (KNPs; 0–2%) and pyracantha extract (PE; 0–1.5 %) on the maintenance of phenolic compounds, antioxidant capacity and microbial properties of ‘Rishbaba’ grape during 60 days at −1 °C using response surface methodology and central composite design. The results showed that the applied coating on Rishbaba grape maintained total phenol, total flavonoids, total anthocyanin, stilbenes (resveratrol and viniferin) and catechin. That also caused higher antioxidant capacity and lower mold and yeast growth in grape during the storage time. Finally, the best cold storage conditions of ‘Rishbaba’ grape were determined by using the edible maltodextrin coating containing 2 % KNPs and 1.5 % of PE for 34 days with a desirability of 0.728 in terms of investigated Characteristics. The optimized sample has the amount of total phenol (5.79 mg/g), total flavonoid (8.95 mg/g), total anthocyanin (6.48 mg/g) and the greatest ability to inhibit DPPH free radical (42.56 %) and the lowest growth rate of mold and yeast (21 Cfu/g).

Emulsion-based edible chitosan film containing propolis extract to extend the shelf life of strawberries

In this study, propolis was first loaded into a conventional oil-in-water emulsion, which was combined with a chitosan film-forming solution to produce propolis emulsion-loaded film (PEF). Strawberries inoculated with Botrytis cinerea coated with PEF and blank emulsion-loaded films (BEF) were stored for 14 days at 4 °C. Compared to BEF, PEF showed superior mechanical and oxygen barrier properties, as well as antioxidant activities, but higher moisture permeability. PEF showed less oil agglomeration on the film surface after drying, as demonstrated by scanning electron microscopy (SEM) analysis. Compared to uncoated strawberries, coatings did not have a significant effect on weight loss or firmness during storage. In contrast, coated strawberries showed elevated total phenolics, anthocyanins, and ascorbic acid retention; however, PEF-coating yielded higher values. Moreover, the PEF coating resulted in a significantly lower reduction of organic acid and total soluble solids. Mold growth was visible in both uncoated and BEF-coated strawberries after 7 days of storage, while PEF-coated fruits showed no visible mold until the end of storage. Starting from day 4, PEF-coated fruits showed lower mold counts (~2 log CFU/g) than other samples. Therefore, the PEF prepared in this study has application potential for the preservation of fresh fruits.

Analysis of the Stress Field in Photoelasticity Used to Evaluate the Residual Stresses of a Plastic Injection-Molded Part.

The degree of quality of thermoplastic injection-molded parts can be established based on their weight, appearance, and defects. However, the conditions of the injection process may induce effects on the mechanical performance of the injected parts, and the residual stresses can cause cracks or early failures when an external load or force is applied. To evaluate these mechanical behaviors, different experimental techniques have been reported in the literature, where digital photoelasticity has stood out both for being a non-contact technique and for achieving quantitative results through sophisticated computational algorithms. Against this background, our proposal consists of analyzing the overall residual stress distribution of parts injected under different molding conditions by using digital photoelasticity. In this case, the specimens are subjected to bending strength tests to identify possible effects of the injection process conditions. The findings show that, at mold temperatures of 80 °C, flow-induced residual stresses increase with packing pressure. However, these internal stress levels do not affect the external load applied by the mechanical bending test, while the mass injected at higher levels of packing pressure helps to increase the bending strength of the injected part. At lower mold temperatures (50 °C), the mechanical strength of the injected part is slightly reduced, possibly due to a lower effect of the packing pressure.

Green productivity and value chain analysis to enhance sustainability throughout the passenger car tire supply chain in Thailand

Although the tire industry is important for the economy of the country, focusing only on productivity will not lead to sustainable production and competitiveness in today's global market. This research aimed to enhance economic and environmental performance throughout Thailand's tire supply chain using green productivity (GP) and value chain analysis. The current performance of the tire supply chain was presented using GP level with value chain analysis for identifying the causes of extravagant resources, energy, or waste. The clean technology (CT) concept was used to develop options to improve GP and obtaining a sustainable tire supply chain. The results showed that the highest GP value of primary and intermediate rubber products was fresh latex and smoke sheet rubber. Cup lump and STR20 block rubber, in contrast, offered the lowest GP. Overuse of chemical fertilizer in the cup lump production, water consumption in the STR20 production and steam consumption in the tire manufacturing process were key issues selected for developing CT options from value chain analysis. The chosen options are to fertilize following the Rubber Research Institute recommendations, recycle used or treated water in the rubber industry and lower mold open time among tire manufacturers to reduce steam and coal consumption. These techniques were predicted to raise the GP value from 0.1495 to 0.1626 in cup lump production, 0.0320–0.0326 in the STR20 plant and 0.0098–0.0114 in a tire factory. It indicated a more sustainable business operation that could reduce environmental impacts and increase competitiveness simultaneously.

The effects of cooling rate (mould temperature) on HDPE gears produced through injection moulding

The effects of mould temperature (cooling temperature) on molten HDPE (Hostalen GC 7260) during manufacture, is evaluated in this paper. HDPE gears were produced at varying mould temperatures using Injection Moulding. Optimised injection values for melt temperature, injection volume, hold pressure, and hold time were obtained, and then held constant while the mould temperature was altered.Analysis on how the mould temperature affected peak melting points and crystallinity were then carried out using differential scanning calorimetry (DSC). These revealed that crystallinity improved as the mould temperature was increased from 22 °C to 65 °C. Gears produced at similar cooling temperatures were then meshed on a gear test rig and run at 1000 rpm, using different torque loadings. Their wear rates, and modes of failure were then analysed, and comparisons were made to ascertain how the differing mould temperatures employed during the injection moulding manufacturing process affected their wear characteristics. Topographical analysis of worn gear teeth was performed using scanning electron microscopy (SEM). It was noted that gear tooth wear and failure was dependent on the mould temperature employed during the manufacturing process. Gears produced at 65 °C showed improved tooth surface wear resistance at lower loads (0.5 Nm and 1 Nm) compared to those produced at 22 °C, but were more likely to fail through tooth fracture at the pitch line due to excessive material removal. Gears produced at lower mould temperatures, on the other hand, exhibited better wear resistance for higher loads (3 Nm and 4 Nm), compared to those produced at higher mould temperatures, and were more likely to fail due to material flow. The results show a correlation between mould temperature, crystallinity, and gear performance. Based on wear rate responses of gears produced at differing mould temperatures to the application of varying torque loadings, a Mould Temperature to Torque Reference Chart for HDPE is presented.

PENGARUH TEMPERATUR CETAKAN TERHADAP STRUKTUR MIKRO DAN KEKERASAN PISTON HASIL PENGECORAN MENGGUNAKAN 3D PRINTING

Motorcycle users in 2019 reached 133,617,012 units in Indonesia. The impact of a large number of motorcycle certainly attracts the interest of the industry to produce two-wheeled automotive vehicles. The piston is part of the engine that functions as a compression barrier in the combustion chamber, the piston material is aluminum alloy. Therefore, research was carried out on making pistons with investment casting methods, physical and mechanical patterns from 3D printers on pistons. This research starts from drawing the piston using CAD (computer-aided design), making a printed pattern from a 3D Printer machine with PLA (polylactide acid) material. The mold pattern is coated with a mixture of gypsum cement and silica powder. The casting process with a pouring temperature of 750ᵒC and a mold temperature of 200 ᵒC, 250 ᵒC, 300 ᵒC, 350 ᵒC, and 400 ᵒC. The results showed the largest grain size at a mold temperature of 400ᵒC. The highest hardness at 200 ᵒC mold temperature is 47.00 HRB and the lowest hardness at 400 ᵒC mold temperature is 40.56 HRB. The higher the temperature of the mold used, the level of porosity of a material will decrease. This is due to the temperature difference when pouring the molten metal and the lower mold temperature. This makes the metal solidification time longer. The higher the mold temperature, the slower the solidification time, the larger the grain structure, and the decreased hardness.

Comparison of Different Techno-Functional Properties of Raw Lemon Pomace and Lemon Pomace Powder, and Development of Nutritional Biscuits by Incorporation of Lemon Pomace Powder

Lemon is one among the fruits of a highly respectable class known as citrus, well known for its nutritious juice and beverage products, rich with a range of micro and macro elements, and functional bioactives. After extraction of juice, the pomace left has great potential as a sustainable agricultural processing by-product, due to its vast application in the food, feed and pharma industries. Lemon pomace powder was prepared from the by-product obtained after the extraction of juice from the lemon. Dried lemon pomace powder contained fiber (60.12 g 100 g<sup>-1</sup>), moisture (10.67 g 100 g<sup>-1</sup>), protein (4.89 g 100 g<sup>-1</sup>), fat (2.17 g 100 g<sup>-1</sup>), sugar (4.81 g 100 g<sup>-1</sup>) and ash (3.21 g 100 g<sup>-1</sup>), indicating higher amounts of ash, fat and fiber contents than wheat flour. The water-holding and oil-holding capacities of lemon pomace powder were noticed 5.9 and 3.2 g, respectively. Lightness (<em>L</em>*) and yellowness (<em>b</em>*) of powder were decreased while redness (<em>a</em>*) was increased in powder as compared to raw pomace. Water activity was decreased, while dry matter and pH of pomace powder were significantly increased as compared to raw pomace. Microbiological analyses revealed lower mold, yeast and total viable counts in lemon pomace powder as compared to raw lemon pomace. Dried lemon pomace powder was replaced with wheat flour at concentrations of 0%, 5%, 10% and 15% in biscuits. The biscuits were evaluated for chemical and sensory properties. Data revealed that the incorporation of lemon pomace powder improved the chemical and sensory properties of biscuits significantly. Highly acceptable biscuits with good sensory properties were obtained by incorporating 10% lemon pomace powder, with the potential use of promoting health.

알루미늄 판재의 Tail Gate Hinge 부품 블랭킹 공정에서 버어 감소 및 융착 방지를 위한 급속 Air Cooling 금형기술

Aluminum alloy is different from high strength steel, which is a hard material. Cracks owing to insufficient elongation in the press forming process and shear stress repeatedly applied in the shear process cause aluminum particles fused to the material surface to fall. To eliminate these, a large waste of manufacturing time occurs due to additional processing operations. We developed a rapid air cooling shear mold with a vortex tube that can prevent fusing of aluminum material at the punch and die edges of the upper and lower molds. The goal was to solve the chronic burr problem by minimizing the thermal occurrence generated during shearing. In the blanking mold of Tail Gate Hinge parts, the temperature inside the mold increases owing to the heat generated during continuous press production. Cooling is possible in an actual mold experiment by applying a rapid air cooling system using a vortex tube.

Process Optimization of Injection Overmolding Structural Electronics with Regard to Film Distortion

The integration of structural electronics in injection-molded parts is a challenging step. The films-comprising of laminated stacks with electronics-are exposed to shear stresses and elevated temperatures by the molten thermoplastic. Hence, molding settings have a significant impact on the successful, damage-free manufacturing of such parts. In this paper, test films with polycarbonate (PC) sheets as outer and two different thermoplastic polyurethanes (TPUs) as middle layers incorporating conductive tracks on a flexible printed circuit board (flexPCB) are manufactured and overmolded with PC. Parameter studies investigating the influence of the melt temperature, mold temperature, injection speed and used TPU layer were performed. The molded parts were inspected visually and compared with a numerical simulation using injection molding software. A shear distortion factor for the TPU layer was derived based on the simulations that linked the shear stresses with the injection time and the softening (melting) of the TPU. The distortion of the films was found to reduce with higher melt temperature, lower mold temperature and faster injection speed. Films using the TPU with the higher melting temperature yielded significantly better results. Moreover, distortion on the films reduced with the increasing distance to the gate and a larger cavity thickness was found to be beneficial. All those relations could be correlated with the shear distortion factor.

Clinical case of rhino-orbital mucormycosis in a convalescent COVID-19 patient: diagnostic and treatment tactics

According to current data, SARS-CoV-2 virus has the ability to cause multi-organ pathology, leading to acute damage of various organs and systems and long-term consequences characterized by polymorphic symptoms. Recently, a high incidence of invasive mycoses, particularly mucormycosis COVID-M, has been noted among the COVID-19 complications. The predisposing factor for the development of this pathology is diabetes mellitus, immunodeficiency states, and prolonged use of high doses of glucocorticosteroids. Mucormycosis is characterized by severe clinical manifestations and high lethality, and timely diagnostics of this pathology often represents a difficult problem. The aim of this study was to analyze a clinical case of rhino-orbital mucormycosis in convalescent COVID-19 patient. In the study, there was used mucopurulent nasal discharge from the patient previously hospitalized with a severe novel coronavirus infection. Here, we describe the methodology allowing to isolate and identify a pure mold fungus culture from the biomaterial using methods of routine bacteriology and MALDI-ToF mass spectrometry. Direct microscopy examination of nasal cavity discharge revealed branched non-septic hyphae with a characteristic branching angle, allowing to preliminarily diagnose invasive mucormycosis. Growth of mycelial fungus colony was observed by using Sabourauds medium with potassium tellurite. Microscopy of the pure culture revealed branching mycelium without septa, broad, with irregular thickness, unsegregated hyphae, and sporangia with a typical column specific to mucormycetes. Analysis of the obtained mass spectra allowed to establish the microbial species identity as Lichtheimia corymbifera. The latter along with other members of the order Mucorales, are known to cause mucormycosis. As a result of antifungal treatment (Amphotericin B) and timely surgical intervention, the patient was discharged from the hospital with prominent clinical improvement and no complaints during further outpatient follow-up period. The analysis of this clinical case showed the lack of alertness in some clinical diagnostic laboratories to detect pathogens of invasive mycoses. To avoid errors, while making a diagnosis, attention should be paid not only to detection of fungal spores in clinical material, but also take into account the structure of mycelium underlying major difference between yeast-like fungi, higher and lower molds. The isolation and identification of a pure pathogen culture allows to confidently verify the diagnosis, timely correct the treatment tactics and monitor circulation of mycotic agents to prevent occurrence of mycoses in most vulnerable patients cohorts.

직접가열 프레스 금형 개발에 의한 고무 성형 에너지 절감

Rubber is positioned as an important material and essential tool and means for mass production of products in all industries due to its unique properties such as sealing, elasticity and shock absorption. However, in the case of conventional press rubber molding, its energy efficiency is low due to considerable heat loss, and the deviation of the temperature distribution of the molding mold is high due to the indirect heating method in which heat is transferred to the upper and lower molds installed on hot plates. The upper and lower heating plates were heated by several heaters installed on the hot plates. The high deviation of the temperature distribution causes unformed defects. Among the rubber mold working methods that consume considerable energy, this study attempted to reduce energy consumption by directly heating the mold via installing a heater inside the upper and lower molds in a compression mold with large energy loss. As a result, compared to the conventional method of transferring heat to the mold by heating the hot plate of the press, energy was saved by 30%, the initial mold heating time was shortened by 20 minutes, and the product defect was reduced with a rate of 25%.

Numerical Simulation and Experimental Validation of Squeeze Casting of AlSi9Mg Aluminum Alloy Component with a Large Size.

The squeeze casting process for an AlSi9Mg aluminum alloy flywheel housing component was numerically simulated using the ProCAST software, and orthogonal simulation tests were designed according to the L16 (4) 5 orthogonal test table to investigate the alloy melt flow rule under four factors and four levels each of the pouring temperature, mold temperature, pressure holding time and specific pressure, as well as the distributions of the temperature fields, stress fields and defects. The results showed that the flywheel housing castings in all 16 test groups were fully filled, and the thinner regions solidified more quickly than the thicker regions. Hot spots were predicted at the mounting ports and the convex platform, which could be relieved by adding a local loading device. Due to the different constraints on the cylinder surface and the lower end surface, the solidification was inconsistent, the equivalent stress at the corner junction was larger, and the castings with longer pressure holding time and lower mold temperature had larger average equivalent stress. Shrinkage cavities were mainly predicted at mounting ports, the cylindrical convex platform, the peripheral overflow groove and the corner junctions, and there was also a small defect region at the edge of the upper end face in some test groups.

Basil, marjoram, nutmeg and oregano essential oils as natural preservatives of Quark-type cheese

This study aims to evaluate the in vitro antimicrobial activity of basil, marjoram, nutmeg, and oregano essential oils to use the essential oil with better results for Quark-type cheese preservation. To verify the shelf life of Quark-type cheese without essential oil (CTL) and Quark-type cheese added with 0.05% essential oil (OE), microbiological and physicochemical analyses were performed for 35 days (4 °C). The acceptability of the product was also evaluated. The oregano essential oil showed strong antimicrobial activity in the disk-diffusion test (34.0 to 51.0 mm), and lower values of minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) against all species of bacteria tested. A lower mold and yeast count (p < 0.05) was observed during storage in OE denoting a positive effect in delaying its deterioration. On the other hand, there was no difference (p > 0.05) between the CTL and OE count of total mesophiles and Enterobacteriaceae. For the physicochemical parameters evaluated, there were no significant differences between the CTL and OE, thus denoting that the typical characteristics of this cheese were maintained. The Quark-type cheese added with oregano essential oil also showed good acceptability (> 7), which is a way to preserve the product with a natural additive.

Bacillus amyloliquefaciens M73 reduces postharvest decay and promotes anthocyanin accumulation in Tarocco blood orange (Citrus sinensis (L.) Osbeck) during cold storage

Due to its antifungal effects on a variety of phytopathogenic fungi and growth-stimulating activity, the effects of Bacillus amyloliquefaciens M73 on the preservation and especially the anthocyanin accumulation in Tarocco blood orange (Citrus sinensis (L.) Osbeck) during cold storage at 4 °C were investigated. Compared with the untreated fruit, B. amyloliquefaciens M73 culture supernatant (BMCS)-treated blood orange exhibited the lower percentage of fruit decay and greater desirable darker purple coloration. BMCS-treated fruit also maintained the lower weight loss and richer contents of total soluble solids, vitamin C, titratable acidity and anthocyanins, with higher transcription levels of anthocyanin biosynthesis related genes of CHS1, CHS2, F3’5’H, ANS, and Ruby in the pulp. The treated fruit had higher activities of peroxidase and polyphenol oxidase that were related to fruit disease resistance, as well as the lower mold count on the pericarp. BMCS treatment did not aggravate the generation of off-flavors during the storage. Our study suggested that B. amyloliquefaciens M73 had the potential to be developed into a novel preservative of high efficiency and low cost on maintaining the storage quality and increasing coloration of Tarocco blood orange during cold storage.

Effect of heat-treated flour on the quality and storage stability of fresh noodles

The effects of heat-treated flour on the quality, water distribution, and molecular weight distribution of protein and volatile compounds in fresh noodles during storage were evaluated. Heat-treated wheat flour (HTWF) at 80°C–100 °C for 30 min was used to prepare noodles (HTFN). Results showed that heat treatment improved the quality of the noodles during storage. Compared with the control samples, the HTFN samples had a lower total plate counts (TPCs), a lower mold and yeast counts (MYCs), and a more stable pH value during storage. Heat treatment provided fresh noodles with bright color and positive texture. Low-field nuclear magnetic resonance (LF-NMR) results indicated that heat treatment restricted water migration with high A21 and minimal T23 (less free water) in the HTFN samples. Heat treatment promoted the aggregation of protein molecules, further inducing a difference in the quality of noodles. Moreover, heat treatment decreased the relative concentrations of free radicals and improved the overall aroma profile.

Study of Monitoring Method and Melt Flow Behavior in Compression Molding Process Using Thermoplastic Sheets Reinforced with Discontinuous Long-Fibers

In compression molding using glass-fiber-mat-reinforced thermoplastic (GMT) sheets, a slightly longer compression waiting time from sheet placement on a lower mold to the start of sheet compression by an upper mold can cause incomplete filling due to a decrease in the sheet temperature. However, precise measurement techniques for compression waiting time have not been sufficiently established. A monitoring system was produced that includes pressure—temperature sensors mounted in a compression mold that can simultaneously measure the pressure and temperature of one local surface. Two types of distance sensors were also used to measure upper mold motion widely and precisely. Determination of compression waiting time was attempted by measuring the moment when the lower mold temperature slightly increases in response to contact with the melted GMT sheet and the moment when the melt pressure increases in response to compression by an upper mold. The results showed that compression waiting time could be precisely calculated using the profile data obtained. Moreover, it was also possible to observe the melt pressure overshoot that occurs depending on sheet stacking patterns and mold cavity shape, although in some cases, the overshoot was not observed. In conclusion, this study has demonstrated that the system is effective in monitoring the compression molding process widely and precisely.

Effects of Mould Temperature on Rice Bran-Based Bioplastics Obtained by Injection Moulding

The high production rate of conventional plastics and their low degradability result in severe environmental problems, such as plastic accumulation and some other related consequences. One alternative to these materials is the production of oil-free bioplastics, based on wastes from the agro-food industry, which are biodegradable. Not only is rice bran an abundant and non-expensive waste, but it is also attractive due to its high protein and starch content, which can be used as macromolecules for bioplastic production. The objective of this work was to develop rice-bran-based bioplastics by injection moulding. For this purpose, this raw material was mixed with a plasticizer (glycerol), analysing the effect of three mould temperatures (100, 130 and 150 °C) on the mechanical and microstructural properties and water absorption capacity of the final matrices. The obtained results show that rice bran is a suitable raw material for the development of bioplastics whose properties are strongly influenced by the processing conditions. Thus, higher temperatures produce stiffer and more resistant materials (Young’s modulus improves from 12 ± 7 MPa to 23 ± 6 and 33 ± 6 MPa when the temperature increases from 100 to 130 and 150 °C, respectively); however, these materials are highly compact and, consequently, their water absorption capacity diminishes. On the other hand, although lower mould temperatures lead to materials with lower mechanical properties, they exhibit a less compact structure, resulting in enhanced water absorption capacity.