Water Retention Capacity Research Articles

Physical and chemical treatments in obtaining and purifying Kombucha SCOBY Cellulose

SCOBY cellulose (CS) is a biopolymer with exceptional physical properties, serving as a source of fiber, water retention capacity, crystallinity, and purity. Its potential as a byproduct of kombucha production and a source of bacterial cellulose (BC) has been a subject of exploration. This study aims to gather information from experimental studies in the scientific literature on various methods of CS extraction, processing, and purification, and their impact on microscopic, macroscopic structure, and functional characteristics. The purification treatments for CS, as described in the literature, include immersion in deionized, distilled, or sterile water, sodium hydroxide, hydrogen peroxide, and sodium hypochlorite under agitation or static mode at different temperatures (23ºC, 30ºC, 50ºC, 80ºC, 90ºC, 110ºC) and under variable contact times with the substance chosen for treatment (1, 2, 20, 24 hours to 3 days). Alkaline treatments on SCOBY cellulose enhance extensibility, viscoelasticity, absorptivity, tensile strength, heat stability, and remove microorganisms, sugars, and other components of the culture medium adhered to the cellulose. With CS being obtained at a low cost and low complexity in the fermentation process, and the potential for less polluting treatments, it presents a sustainable process and source of CB that can be applied in a variety of industries, particularly in the exciting field of food.

Study of Ancient and Modern Wheat Grain Textures, Physiochemical Properties, and Biscuit Quality

We conducted a comprehensive study to investigate how different types of wheat affect the quality of biscuits. Our research included an ancient wheat variety called T. spherococcum, as well as present-day cultivated hard wheat varieties and soft wheat varieties (T. aestivum). We compared three hard wheat varieties (MACS6478, MACS2496, NI5439) and two soft wheat varieties (HS 490, NIAW3170) with ancient wheat (T. spherococcum) to analyze various aspects such as agronomic, grain and flour physicochemical, dough mixing, and biscuit quality parameters. Our results showed that soft wheat has a weaker association between starch and the protein matrix in the grain, leading to less starch damage, a lower particle size index (PSI), and higher flour recovery than hard wheat. Soft wheat flour also has lower gluten strength, a higher gliadin fraction, and decreased mixing resistance. Additionally, soft wheat flour has lower starch damage, which results in lower alkaline water retention capacity (AWRC) than hard wheat flour. These physiochemical findings helped us better understand how these traits related to biscuit quality. The study concluded that simple and fast physiochemical tests such as PSI, MST, AWRC, and flour protein content would help to select the best biscuit-quality wheat. These tests are quick and simple and do not need high-end sophisticated instruments. We also concluded that T. spherococcum was a hard wheat, and its flour physicochemical dough mixing properties were similar to that of hard wheat. It also produced inferior quality biscuits like hard wheat.

Effects of Varied Tillage Practices on Soil Quality in the Experimental Field of Red-Soil Sloping Farmland in Southern China

Red-soil sloping farmland in southern China plays a crucial role in the local economy and food production. However, improper tillage practices have resulted in topsoil degradation and deteriorating soil quality. This study investigated changes in soil physico-chemical properties under four tillage methods—cross-slope ridge tillage (RT), down-slope ridge tillage (DT), plastic mulching (PM), and conventional tillage (CT)—on red-soil sloping farmland. The study applied the Soil Management Assessment Framework (SMAF) to assess the influence of these tillage practices on soil quality. Results indicated that PM can increase the total porosity of the soil, reduce soil bulk density, and simultaneously decrease soil surface-water evaporation, significantly improving the soil’s water-retention capacity. RT improved soil aggregate formation and stability, leading to increased macro-aggregate content, mean weight diameter, and soil water-stable aggregate stability rates. PM and RT effectively preserved soil nutrients like total nitrogen and organic matter, although PM lowered soil pH, potentially causing acidification. RT demonstrated the highest soil quality, with PM following. Crop growth positively impacted soil macro-aggregate content and stability, showing continuous improvement in soil structure and quality (p < 0.05). Priority should be given to RT in red-soil sloping farmland, followed by PM and CT, while avoiding DT if possible. This research furnishes valuable scientific substantiation for the selection of optimal tillage practices in the preservation of soil quality on red-soil slopes.

Effect of Three Different Types of Biochar on Bioelectricity Generated from Plant Microbial Fuel Cells under Unsaturated Soil Condition.

Plant microbial fuel cell (PMFC) is an emerging technology, showing promise for environmental biosensors and sustainable energy production. Despite its potential, PMFCs struggle with issues like low power output and limited drought resistance. Recent studies proposed that integrating biochar may enhance PMFC performance due to its physicochemical properties. The influence of different biochar types on PMFC efficiency has been minimally explored. This study aims to fill this gap by evaluating the performance of PMFCs integrated with various biochar types under unsaturated soil conditions. The study found that the addition of biochar types─specifically reed straw biochar (RSB), apple wood biochar (AWB), and corn straw biochar (CSB)─significantly influenced the performance of PMFCs. RSB, with its large surface area and porous structure, notably increased the current output by reducing soil resistance and enhancing electron transfer efficiency in microbial reduction reactions, achieving a peak power density of approximately 1608 mW/m2. AWB, despite its less porous structure, leveraged its high cation exchange capacity and hydrophilic functional groups to foster microbial community growth and diversity, thereby also increasing bioelectricity output. Conversely, CSB, with its large surface area, showed the least improvement in PMFC performance due to its layered structure and lower water retention capacity. Additionally, under drought conditions, PMFCs with added RSB and AWB exhibited better drought resistance due to their ability to improve soil moisture characteristics and enhance soil conductivity. The addition of biochar reduced soil resistance, increasing the bioelectric output of PMFCs and maintaining good performance even under low moisture conditions. This study highlights the critical role of biochar's surface area and functional groups in optimizing PMFC performance. It enhances our understanding of PMFC optimization and might offer a novel power generation method for the future, while also presenting a fresh strategy for soil monitoring.

Preparation and Characterization of Multi-Network Crosslinked Gels for Preventing Spontaneous Combustion of Coal

ABSTRACT In order to improve the inhibition performance of a retardant in various stages of coal spontaneous combustion, this study selected guar gum (guar) mixed with sodium tetraborate to form a multi-web gel. Then, polyethylene glycol (PEG) was added for the insertion and modification to improve the physical inhibition effect. Furthermore, we compounded the composite guar/PEG with the chemical retardant 2-hydroxyphosphonoacetic acid (HPAA) to prepare a composite retardant with the effect of full-stage inhibition. Multi-web gel composite inhibitor with a full-stage inhibition effect was prepared. Response surface analysis was used to determine the optimal solution. Scanning electron microscopy tests revealed that the surface folds of PEG/guar increased and the water retention capacity was greatly enhanced. The plugging wind experiment results show that the limiting air pressure of the gel material is 249 Pa, which can match the downhole plugging wind work. Using XRD experiments, the diffraction angle of PEG/guar was narrowed from 18.20° to 17.64°, the crystal layer spacing was increased from 4.8685 nm to 5.0218 nm, and PEG was successfully intercalated into the guar. Using Fourier-transform infrared spectroscopy, it was found that the content of free hydroxyl groups and aliphatic groups became lower, and the content of carbonyl groups and ether bonds increased, which greatly enhanced the antioxidant capacity of coal. Using thermogravimetric analysis, the characteristic temperature points of single and composite inhibitors were examined macroscopically. The results showed that the inhibition treatment could obviously chelate the transition metal ions in the coal samples, which greatly inhibited the process of coal oxidation and achieved the purpose of inhibiting the spontaneous combustion of coal.

Development of a cationic bacterial cellulose film loaded with anionic liposomes for prolonged release of oxacillin in wound dressing applications

Dressings should protect wounds, promote healing, absorb fluids, and maintain moisture. Bacterial cellulose is a biopolymer that stands out in biomaterials due to its high biocompatibility in several applications. In the area of dressings, it is already marketed as an alternative to traditional dressings. However, it lacks any intrinsic activity; among these, the need for antimicrobial activity in infected wounds stands out. We developed a cationic cellulose film by modifying cellulose with 1-(5-carboxypentyl)pyridin-1-ium bromide, enhancing its wettability (contact angle: 26.6°) and water retention capacity (2714.37 %). This modified film effectively retained oxacillin compared to the unmodified control. Liposomal encapsulation further prolonged oxacillin release up to 11 days. Both oxacillin-loaded films and liposomal formulations demonstrated antimicrobial activity against Staphylococcus aureus. Our findings demonstrate the potential of chemically modified cellulose as a platform for controlled anionic antibiotics and/or their formulations delivery in wound care.

Effects of Bacillus subtilis on cotton physiology and growth under water and salt stress

The scarcity of fresh water resources has severely limited agricultural production in arid areas. Although brackish water irrigation or fresh water deficit irrigation can alleviate the water resources crisis, both may cause water and salt stress to crop. Therefore, this study is based on the functional advantages of Bacillus subtilis in soil improvement and crop growth promotion to alleviate water and salt stress and build safe and efficient water-saving irrigation patterns. In this study, cotton (No. 50 Chuangmian) was selected as the research crop, and five application rates of Bacillus subtilis (0, 22.5, 45, 67.5 and 90 kg·ha−1) were combined with three irrigation patterns (brackish water, fresh water and fresh water deficit irrigations) to study the effects of Bacillus subtilis on soil moisture and salinity, soil microbial community, cotton physiology and growth under water and salt stress. The results showed that Bacillus subtilis could enhance soil water retention capacity, promote soil desalination, improve cotton growth indices (plant height, stem diameter, leaf area index, dry matter accumulation), and then increase yield and water use efficiency (WUE). Compared with the control treatment, the yield and WUE of Bacillus subtilis application treatments increased by 3.32–54.67 % and 1.68–41.07 %, respectively. In the cotton physiology characteristics, Bacillus subtilis increased proline content and the activity of superoxide dismutase, peroxidase and catalase while decreased malondialdehyde content in cotton leaves. Bacillus subtilis could enhance the relative abundance of bacteria with the functions of nitrogen fixation, stress resistance and biocontrol. A structural equation model proved that Bacillus subtilis could improve yield and WUE indirectly by directly improving soil microbial diversity, alleviating water and salt stress, and then improving cotton physiology and growth. According to a comprehensive evaluation of cotton physiology and growth, it was determined that the optimal improvement effect was achieved when the application rate of Bacillus subtilis was 45 kg ha−1; the synergistic effect of brackish water irrigation and Bacillus subtilis (45 kg·ha−1) was superior to that of fresh water deficit irrigation combining with Bacillus subtilis (45 kg·ha−1), which could be considered a priority strategy for alleviating the fresh water crisis in arid areas and promoting the efficient increase in cotton yield.

Field assessment of Lake Erie dredged sediment for specialty crops cultivation

AbstractAnnually, approximately 1.5 million tonnes of sediment are dredged from federal navigational channels in Lake Erie. Recognizing the potential influence of Lake sediments on soil compaction, structure, water retention capacity, and aeration, this research assessed the agronomic performance of selected specialty crops under varying sediment ratios in an open‐field production system. The experimental design involved three sediment application rates: 0 tonne (100% farm soil), 0.7 tonne (90% farm soil and 10% sediment), and 7 tonnes per bed (100% sediment). Lettuces (Lactuca sativa L.) were harvested 35 days after planting, with assessments including fresh and dry weights of leaves root biomass and root length measurements. Radishes (Raphanus sativus L.) were evaluated for root length, leaf fresh weight, root fresh weight, and diameter. Tomatoes (Solanum lycopersicum L.) plants were monitored for plant height and stem diameter. Fruit harvest occurred at days 70 and 75 post‐transplant. Metrics such as total number of marketable fruits, total fruit weight, number of US grade‐1 fruits, and polar and equatorial diameters were recorded. The results revealed significant positive effects of the 7‐tonne sediment treatment on lettuce, including increased dry leaf and root biomass, root lengths, and fresh weight. Similarly, radishes exhibited enhanced weight and length when grown in beds with 7 tonnes of sediment. Tomatoes from the 7‐tonne sediment treatment displayed higher values in plant measurements and harvested fruits. Overall, the findings indicate that soils treated with Lake Erie sediment positively influence the development and production of lettuce, radishes, and tomatoes compared to untreated soils.

Effect of stepwise cooking on the water-retention capacity and protein denaturation degree of chicken breast

This study investigated the impact of different center temperatures (60 °C, 65 °C, 70 °C) combined with low temperature long time cooking (cooking at 60 °C for 30 min or 60 min) on the water-retention capacity of chicken breasts. The effects of different heat treatment methods on microstructure, texture parameters, water content, cooking loss, color, pH value, protein denaturation degree and secondary structure content of chicken breast were analyzed. The results revealed that both center temperature and low temperature long times cooking (LTLT cooking) time significantly influenced the water-retention capacity of chicken breasts (P < 0.05). With increasing heat exposure levels, there was a corresponding rise in pH value as well as protein solubility and hydrophobicity in meat. This led to increased alignment of myofibrils along with gradual structural disruption and connective tissue efflux resulting in significant increases in meat hardness, chewiness and cooking loss (P < 0.05). However, when the center temperature reached 70 °C with an LTLT cooking time of 60 min, the muscle fiber structure is almost completely destroyed, causing the connective tissue between the muscle bundles or fibers to refill, resulting in a random coil content increase of about 2%, increased the water content by around 12% and decreased hardness by about 31%. These findings demonstrate that the group subjected to a combination treatment involving a center temperature of 70 °C and an LTLT cooking time of 60 min was effective in enhancing the water content while reducing the hardness of meat.

Evaluation of antinutrients, nutritional, and functional properties in sacha inchi (Plukenetia volubilis L) cake treated with hydrothermal processes

Applying heat treatments using an autoclave and hot air sterilization can alter the proximal composition, technofunctional properties, and antinutrient content of Sacha inchi (P. volubilis) oil press cake. The autoclave and hot air treatments significantly reduced antinutrients compared to the control. The samples treated with autoclave and hot air sterilization exhibited a significant decrease in alkaloids, nitrates, tannins, saponins, and trypsin inhibitors compared to the control sample. However, the 20-min autoclave treatment did not significantly reduce the saponin antinutrients. Phytic acid significantly decreased in the 30-min hot air sample and autoclave 20-min/hot air treatments, respectively. On the other hand, the levels of antinutrients oxalate and thiocyanates did not significant difference between the control and hot air treatments. However, the autoclave treatment resulted in a significant reduction in oxalates. The study found that hydrotreatments at temperatures of 121 °C with humid heat - autoclave showed significant differences in protein content compared to the control sample, with content of 37.75 + 0.2 g/100g. Samples treated with an autoclave for 10, 20, and 30 min showed values of protein 53.19 + 0.28, 66.08 + 2.6, and 70.12 + 0.48 g/100g, respectively. Meanwhile, samples treated with dry heat showed significant differences with the sample treated for 10 min having a protein content of 60.21 + 6.80 g/100g. The techno-functional properties analyzed in the study demonstrated a significant decrease in hydrating properties such as water holding capacity (WHC), water retention capacity (WRC), and swelling capacity (SC) due to changes in the solubility of proteins for the two treatments and the oil holding capacity (OHC) property showed a significant increase. Finally, water's presence during hydrothermal treatments significantly reduces antinutrients, providing guidance for analyzing other study variables.

Impact of natural biochar on soil water retention capacity and quinoa plant growth in different soil textures

Although data regarding the effect of different types of synthetic biochar on plant performance and physical and chemical characteristics of soil is widely available, the effect of natural biochar in this respect is not well known, so far. The purpose of this research was to investigate the effect of 650-million-years old natural biochar at three application levels of 0 %, 2.5 % and 5 % by weight on yield parameters of quinoa plant and the soil water retention characteristic curve in sandy loam, loam, and clay textural classes. The results showed that the application of 5 % natural biochar to the loam soil increased the thousand seed weight by 8 %, but adding 2.5 % of biochar to the sandy loam soil increased biological yield by 2 %, and in loam soil increased root volume by 409 %, compared to the control. The results of the physical parameters of the soil showed that the application of biochar in three soil textures caused an increase in moisture content at the field capacity (1.8 %-11.22 %), a decrease in macropores in the range of 10–46 %, and an increase in micropores in the range of 0.2–10 % in three soil textures. Therefore, it can be concluded that the potential of natural biochar storage affected the physical properties of the soil and increased soil water retention while improving important soil functions.

Insight into the preparation and improved properties of cellulose citrate ester hydrogel slow-release fertilizer

The development of new fertilizers with significant water retention capacity and sustainable nutrient supplementation for arid and semi-arid regions remains an important challenge. In this study, a novel slow-release fertilizer (CCEH-SRF) based on cellulose citrate ester (CCE), which is low-cost and biocompatible, was developed using epoxy chloropropane (ECH) as a cross-linker and urea as a fertilizer. The CCEH-SRF exhibited higher water swelling (21.58 g·g−1) and water retention capacity (20.69 % in 7 days) compared to the neat cellulose hydrogel (CH). Furthermore, the CCEH-SRF demonstrated improved release performance with cumulative slow-release rates of 48.0 % at 2 hours in water, and 5.3 %, 65.9 %, and 66.7 % after 1 day, 26 days, and 35 days respectively in simulated soil column percolation assays, whereas the CH-based SRF had inferior release performance. The nutrient slow-release of CCEH-SRF followed the First-order kinetic model and Fick diffusion process accurately. Additionally, the developed CCEH-SRF showed positive growth promotion effects on maize seedlings, indicating its promising practical applicability. Therefore, this work provides a novel approach for developing environmentally friendly SRFs by utilizing natural cellulose derivatives from readily available agricultural waste in fields such as waste reuse, sustainable agriculture, and horticulture.

Effect of Pistachio Shell Biochar and Organic Cow Manure Application on Plant Growth, Water Retention Capacity and Nutrient Stress Mitigation

AbstractSustainable crop production supports food security by mitigating water and nutrient stress from manures by excessively drained water. Cow manure is a good nutrient resource to enhance soil fertility and plant growth but requires a suitable amender to reduce the nutrients loss by leaching. Worldwide more than 20,400 metric tonnes of pistachios were consumed where roughly 30% of the weight of the nut is the shell which could be a good feedstock for biochar production. Therefore, this study was conducted to produce biochar from pistachio shell by pyrolysis process at three different temperatures 350 to 550 °C and based on various properties characterization, the biochar at 450 °C was amended with 0% (control), 2%, 4% and 8% to the cow manure for eggplant growth (Solanum melongena). Out of all fractions of biochar application, 2% biochar has virtuous performance to increase 5.63 ± 1.45 cm of plant height, 1.33 ± 4.79 cm leaf length and 1.90 ± 4.43 cm leaf width over the control. The leaf chlorophyl content and plant biomass were also significantly (p = 0.02) increased compared to the control. The lower fraction of biochar application showed almost similar water retention capacity with control (p &gt; 0.11) due to the better plant growth. Based on the findings of this study, it is proposed that lower fraction of biochar application with manure is a constructive solution to improve soil quality, reduce nutrient loss and eggplant growth. Under the circular economy and frameworks of sustainability, pistachio shell biochar production has a high legislative attention on valorizing nutshell wastes. Graphical Abstract

Optimization of peapod peel biochar amendment for sustainable agriculture by surface response methodology towards water-food-environment nexus

Valorization of food waste to biochar offers economic and environmental opportunities for sustainable agriculture production. Peapod (Pisum sativum) peel is a high-content lignocellulose vegetable waste and was used in this study to produce biochar through pyrolysis temperatures of 350, 450, and 550 °C, with a heating rate of 5 °C/min for 30 min and thereafter characterized for its various properties. The biochar produced at 350 °C, exhibiting the best soil amendment properties was used for pot testing with mung bean (Vigna radiata). The optimization of plant growth, soil water retention capacity, and microbial activity were determined using response surface methodology (RSM) with three design factors: (a) biochar loading rates (0 %, 0.5 %, and 1 %), (b) temperature (30–40 °C), and (c) quantity of water supplied (50–60 mL/day). The results showed that applying 0.5 % biochar with a water supply of 55 mL/day at 35 °C resulted in optimal responses for seed germination, plant height, and leaf development. Applying 1 % biochar with a water supply of 55 mL/day at 35 °C showed optimal responses for leaf area and leaf chlorophyll content. Stomatal conductance and catalase activity showed optimal responses for 1 % biochar applied with a water supply of 60 mL/day at 40 °C. Urease activity and water retention capacity showed optimal responses when 1 % biochar was applied with a water supply of 60 mL/day at 30 °C, respectively. This study demonstrates the potential use of peapod peel biochar in water-food-environment nexus, with a lower dose and lesser volume of water demand.

A comprehensive decision-making approach for the application of biochar in agriculture to enhance water security: A GIS-AHP based approach

In the context of climate change, biochar application is a promising approach to mitigate the adverse effects of climate change on agriculture. However, the selection of suitable biochar produced from food waste and optimization of loading rates to improve soil quality remains a significant challenge. This study explores the potential impact of biochar application using an integrated analytical hierarchy process (AHP) and geographical information system (GIS) approach. The study first aims to develop an AHP model to prioritize the appropriate biochar source and dosage for soil amendment. The different biochar sources considered are: peas pod shell, pistachio shell, and mixed vegetable waste. The AHP design evaluated the weight percentage of different types of biochar amendments ranging from 0 % to 8 % based on soil quality, nutrient analysis and water retention capacity. Furthermore, an integrated spatial analysis case study was conducted for fodder farms across Qatar using GIS mapping with seasonal variation to evaluate the impact of biochar on water management. According to the AHP decision making, 2 % mixed vegetable waste biochar achieved the goal with the highest priority score, with a value of 0.29, followed by 2 % pistachio shell biochar with a score of 0.22. This is attributed to the high water retention rate determined from the experimental study. The 2% biochar amendment retained 20 % more water compared to the 0 % biochar. Results from the GIS mapping identified priority areas for improving water retention and soil quality. The evapotranspiration maps for winter and summer generated using GIS provide valuable insights into the spatial disributio of biochar application across Qatar fodder farms. The outcomes may encourage policymakers and stakeholders to consider valorizing food waste into biochar.

Bacterial cellulose with CHAPK-mediated specific antimicrobial activity against Staphylococcus aureus

Wound healing represents a complex biological process often hampered by bacterial infections, in particular those caused by Staphylococcus aureus, which is already multiresistant to many antibiotics. In this sense, enzybiotics have additional advantages over conventional antibiotics, since they provide pathogen specificity and do not contribute to antibiotic resistance. However, their soluble administration at the wound site would result in enzyme leakage. On the other hand, bacterial cellulose (BC) pellicles present a very promising dressing and scaffold, given its high purity, water retention capacity, and barrier effect in the wound against possible contaminants. In this study, we present a novel approach that incorporates the enzybiotic CHAPK into BC to develop functionalized membranes that exhibit targeted and controlled antimicrobial activity against S. aureus. The kinetic tests revealed a continuous loading of the enzybiotic into BC until it reaches a maximum and a two-stage release process, characterized by an initial fast release followed by a sustained release. Attenuated total Reflection Fourier Transform Infrared Spectroscopy (ATR-FTIR), Scanning Electron Microscopy (SEM), and Confocal Laser Scanning Microscopy (CLSM) confirmed the incorporation and the preferential surface localization of CHAPK within the BC membranes. Finally, the BC/CHAPK materials demonstrated the sustained reduction of up to 4 logarithmic units in the viability of S. aureus. Overall, the biomaterials developed here exhibit promising antimicrobial efficacy against S. aureus, offering a potential strategy for wound management and skin infection control while maintaining unharmed the commensal skin microbiota, which impairment could compromise the integrity of the skin barrier function.

Macroscopic and molecular scale assessment of thermal effects on soil-water interactions of unsaturated diesel-contaminated soils

The soil-water interactions of unsaturated diesel-contaminated soil are crucial for assessing pollution transport during thermal remediation. This paper aims to improve our understanding of this issue by measuring the matric suction of unsaturated contaminated kaolin and carrying out molecular dynamics simulations under thermal conditions. Results show that the increase in pollutant concentration could reduce the water retention capacity of diesel-contaminated kaolin due to changes in electrochemical properties and pore characteristics of samples, as well as a decrease in interfacial tension. On the other hand, pollutants formed a protective film on the kaolinite surface to act as a liquid bridge and prevent water loss at higher temperatures, as confirmed by Fourier transform infrared spectroscopy. With rising temperatures (50–60 °C), kaolin matric suction generally decreased with higher pollutant concentrations, but this trend was not very evident at lower pollution concentrations (0–10,000 mg/kg). In addition, molecular dynamics simulations were used to demonstrate the validity of these findings. The presence of pollutants might strengthen the interaction energy between kaolinite and water (for example, increasing from 276.52 kcal/mol (25 °C) and 267.95 kcal/mol (40 °C) at 8000 mg/kg to 296.54 kcal/mol (25 °C) and 292.46 kcal/mol (40 °C) at 10,000 mg/kg), thereby enhancing the water retention capacity of kaolin. In short, the study revealed that the coating of pollutants on kaolinite could act as a protective film, which binds water molecules through van der Waals and electric field forces and thereby reduces the sensitivity of water retention capacity to temperature.

Enhancement of physicochemical, in vitro hypoglycemic, hypolipidemic, antioxidant and prebiotic properties of oat bran dietary fiber: Dynamic high pressure microfluidization

To improve the physicochemical and functional properties of oat bran dietary fiber (ODF) and the comprehensive utilization of oat bran, dynamic high-pressure microfluidization (DHPM) was utilized to treat ODF at different pressures. The particle size, physicochemical, functional and probiotic properties of the ODF samples were analyzed to investigate the modification effect of DHPM. After DHPM modification, the microstructure of ODF was broken, the particle size decreased and the specific surface area increased, with the best effect under 420 MPa pressure treatment. The structural breakage and the increase in the specific surface area of ODF may led to the enhancement of its physicochemical and functional properties, and it had greater advantages in terms of the water retention capacity (2.13 ± 0.01 g/g), oil retention capacity (8.46 ± 0.07 g/g), bile salt binding capacity (52.67 ± 1.21 mg/g) and cholesterol binding capacity (1.03 ± 0.02 mg/g). cholesterol binding capacity (1.03 ± 0.02 mg/g). Meanwhile, ODF also remodelled the gut microbiota of the obese population and increased the relative abundance of beneficial bacteria. In conclusion, DHPM treatment effectively enhanced the physicochemical and functional properties of ODF and broadened its applications in the food industry.

Mechanical and hydraulic characteristics of unvegetated or vegetated loess soils amended with xanthan gum

With the development of western and central China, the increasing construction of transportation infrastructures (e.g., roads, railways, etc.) has been producing a large number of man-made slopes in loess regions. Biopolymer as an eco-friendly stabilizing material, has a great potential to amend soils for the purpose of ground improvement and slope stabilization, with its application in vegetated soils particularly at the initial growing stage to support vegetation growth as well as offer reinforcement to unprotected soils being reported recently. In the current study, the contribution of xanthan gum (XG) to both mechanical and hydraulic behaviors of the unvegetated and vegetated loess soils subjected to climatic wetting–drying cycles under the impacts of degree of compaction and biopolymer content are explored, whilst the effectiveness of the two XG-based soil reinforcing methods (with and without vegetation) are compared. Results indicate that XG treatment improved the water-retention capacity of loess soils to an extent that even the degradation of water retention upon initial wetting–drying cycles could be mitigated particularly at higher degrees of compaction. The strengthened shear resistance of loess soils was observed, mainly attributed to the increased soil cohesion, whilst the friction angle remained almost constant. The unvegetated loess soils basically had an increased cohesion proportional to the XG content up to 1.00% of the dry soil mass, whilst the vegetated soils had the highest soil cohesion at a fixed XG content of 0.50% which corresponded to the mostly promoted vegetation growth. Although a dense soil structure inhibited the seed germination and growth of sprouts and roots, it contributed to the overall shear strength of the vegetated soils similar to its effect on the unvegetated soils. XG amendment outperformed planting vegetation at enhancing soil shear strength at a degree of compaction of 95% (comparable to those adopted for design of highway subgrade), whilst providing XG in combination with vegetation was able to result in a more sizable strength increment over the summation of gains in strength by utilizing XG and vegetation separately, suggesting the considerable potential of XG in assisting vegetated soils for ecological slope stabilization. The results obtained from the current research support the broader usage of biopolymers (either used alone or in combination with vegetation) as reliable geotechnical engineering materials in practical implementations.

Enhancing structural strength and water retention of crosslinked polyacrylamide gel with the T-ZnOw

Crosslinked polyacrylamide gel serves as an effective plugging material, crucial for preventing water/gas channeling in reservoirs and enhancing the swept volume and oil recovery. However, its practical application encounters a significant challenge in maintaining long-term stability of strength and volume, particularly under high temperatures. This study investigates the reinforcement of polyacrylamide gel with three-dimensional (3D) nanomaterials, specifically tetra-needle-like zinc oxide whiskers (T-ZnOw), to enhance its structural stability and bound water content. The stress sweep tests showed that the addition of 0.15 wt% T-ZnOw increased the maximum elastic modulus of the gel to 28.5 Pa, representing a 51.2 % improvement compared to before the addition. After 60 days of high-temperature aging at 130 °C, the T-ZnOw strengthened gel still maintained an elastic modulus of 21.8 Pa. With increasing T-ZnOw concentration, the yield point of the gel increased from 4.74 Pa to 9.57 Pa, the anti-deformation of the gel has significantly increased. The stability test results in high salinity water indicate that at a salinity of 150,000 mg/L, the dehydration rate of the strengthened gel is less than 5 %, with an elastic modulus retention rate exceeding 88 %. Furthermore, thermodynamic testing confirms the enhanced thermal degradation resistance and water retention capacity of the gel. Under reservoir temperature conditions, the T-ZnOw strengthened gel exhibits a weight loss of less than 3 %. Additionally, the inclusion of T-ZnOw results in an increase in the bound water capacity index from 4.65 to 12.28. In conclusion, the integration of T-ZnOw into the polyacrylamide gel network not only enhances its mechanical performance and water retention under high-temperature conditions but also demonstrates superior stability in high-salinity environments. This innovative material shows significant potential for improving oil recovery rates in high-temperature reservoirs and can be applied to other high-temperature underground scenarios such as geothermal development and CO2 utilization and storage.