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(1) Background: this article focuses on the durability decline problem of rammed earth buildings in Paishan Village, Zhuhai City under the influence of complex environments. It aims to reveal the erosion mechanisms of rammed earth walls caused by different environmental factors (acid rain, salt spray, humidity, biological activities, etc.), and provide a scientific basis for formulating targeted remediation strategies. (2) Methods: a technical framework combining macroscopic investigation and microscopic analysis was adopted. Ion chromatography, scanning electron microscopy (SEM), and characterization (XRD) were used to study the damage to buildings in Paishan Village under the influence of different environmental factors. (3) Results: The acid rain and sulfate buildup could cause cracks and peeling on the south wall of the rammed earth wall. Salt spray and high humidity conditions exacerbated surface weathering on the west wall. Vibrant biological activity and high humidity made the north wall’s minerals easily dissolve, leaving the structure loose. The east wall was affected by the changing dynamics of carbonate rocks, which made it more vulnerable to weathering. (4) Conclusion: according to the analysis of different walls, specific steps should be taken during future restoration to improve the durability of rammed-earth buildings. Full article

Unconventional heavy oil reservoirs are particularly susceptible to steam breakthrough, which significantly reduces crude oil production. Profile control is a crucial strategy used for stabilizing oil production and minimizing production costs in these reservoirs. Conventional plugging agent systems used in the thermal recovery of heavy oil currently fail to meet the high-temperature, high-strength, and deep profile control requirements of this process. Precipitation-type calcium salt blocking agents demonstrate long-term stability at 300 °C and concentrations up to 250,000 mg/L, making them highly effective for profile control and channeling blockage during the steam injection stages of heavy oil recovery. This study proposes two types of precipitation-type calcium salt blocking agents: CaSO₄ and CaCO₃ crystals. The precipitation behavior of these agents was investigated, and their dynamic growth patterns were examined. The calcium sulfate blocking agent exhibits a slower crystal precipitation rate, allowing for a single-solution injection, while the calcium carbonate blocking agent precipitates rapidly, requiring a dual-solution injection. Both systems incorporate scale inhibitors to delay the growth of calcium salt crystals, which aids in deep profile control. Through microscopic visualization experiments, the micro-blocking characteristics of the calcium salt blocking agent systems within pores were compared, elucidating the blocking positions of the precipitated calcium salts under porous conditions. Calcium sulfate crystals preferentially precipitate in and block larger pore channels, whereas calcium carbonate crystals are more evenly distributed throughout the pore channels, reducing the reservoir’s heterogeneity. The final single-core displacement experiment demonstrated the sealing properties of the precipitation-type calcium salt blocking agent systems. The developed precipitation-type calcium salt blocking agent systems exhibit excellent profile control performance. Full article

Colitis in equines has high morbidity and mortality rates, which severely affects the development of the equine-breeding industry. With the issuance of antibiotic bans, there is an urgent need for healthier and more effective alternatives. In recent years, probiotics have been widely used as microbial feed additives in animal husbandry, playing a crucial role in preventing and treating diarrhea and regulating host immune function. In this study, we isolated and screened a strain with rapid and stable acid production using bromocresol purple, litmus milk coloration tests, and acid production performance assessments. Based on morphological characteristics, physiological and biochemical properties, and 16S rDNA identification, the strain was identified as Pediococcus pentosaceus and named M6. The Pediococcus pentosaceus M6 exhibited stable growth and tolerance to high temperatures, acid and bile salt concentrations, and simulated gastrointestinal fluid environments. The M6 strain demonstrated good antibacterial effects against Escherichia coli, Staphylococcus aureus, and Salmonella. The M6 strain did not produce hemolysis zones on Columbia blood agar plates, indicating its high safety, and was found to be insensitive to 12 antibiotics, including cephalexin and neomycin. Additionally, intervention in mice with dextran sulfate sodium (DSS)-induced colitis alleviated weight loss and shortened colon length. To a certain extent, it regulated the expression of inflammatory cytokines and the gut microbiota within the body and reduced inflammatory cell infiltration and intestinal barrier damage. In summary, the isolated Pediococcus pentosaceus M6 strain exhibited excellent probiotic properties and could alleviate DSS-induced colitis in mice, suggesting its potential application value as a probiotic in animal husbandry. Full article

Water quality in urban streams is critical for the health of aquatic and human life, as it impacts both the environment and water availability. The strong impacts of changing climate and land use on water quality necessitate a better understanding of how stream water quality changes over space and time. To this end, four key water-quality parameters—Escherichia coli (E. coli), nitrate (NO₃⁻), sulfate (SO₄²⁻), and chloride (Cl⁻)—were collected at 12 sites along Fall Creek and Pleasant Run streams in Indianapolis, Indiana USA from 2003 to 2021 on a seasonal basis: March, July, and October each year. Two-way ANOVA tests were used to determine the impacts of seasonality and location on these parameters. Correlation and RDA (redundancy analysis) were used to determine the importance of climatic drivers. Linear regressions were used to quantify the impacts of land-use types on water quality integrating buffer zone size and sub-watershed analysis. Strong seasonal variations of the water-quality parameters were found. March had higher levels of NO₃⁻, SO₄²⁻, and Cl⁻ than other months. July had the highest E. coli concentrations compared to March and October. Seven-days antecedent snow and precipitation were found to be significantly related to Cl⁻ and log₁₀(E. coli) and can explain up to 53% and 31% of their variations, respectively. Spatially, urban built-up land in a 1000 m buffer around the sampling sites was positively correlated with the log₁₀(E. coli) variation, while lawn cover was positively related to NO₃⁻ concentrations within 500 m buffers. Conversely, NDVI (Normalized Difference Vegetation Index) values were negatively related to all variables. In conclusion, E. coli is more impacted by higher precipitation and urban land coverage, which could be related to more combined sewer overflow events in July. Cl⁻ peaking in March and its relationship with snow indicate salt runoff during snow melting events. NO₃⁻ and SO₄²⁻ increases are likely due to fertilizer input from residential lawns near streams. This suggests that Indianapolis stream water-quality changes are influenced by both changing climate and land-cover/-muse types. Full article

Asphalt pavements are subjected to both repeated vehicle loads and erosive deterioration from complicated environments in service. Salt erosion exerts a serious negative impact on the service performance of asphalt pavements in salt-rich areas such as seasonal frozen areas with snow melting and deicing, coastal areas, and saline soils areas. In recent years, the performance evolution of asphalt materials under salt erosion environments has been widely investigated. However, there is a lack of a systematic summary of salt erosion damage for asphalt materials from a multi-scale perspective. The objective in this paper is to review the performance evolution and the damage mechanism of asphalt mixtures and binders under salt erosion environments from a multi-scale perspective. The salt erosion damage and damage mechanism of asphalt mixtures is discussed. The influence of salt categories and erosion modes on the asphalt binder is classified. The salt erosion resistance of different asphalt binders is determined. In addition, the application of microscopic test methods to investigate the salt damage mechanism of asphalt binders is generalized. This review finds that the pavement performance of asphalt mixtures decreased significantly after salt erosion. A good explanation for the salt erosion mechanism of asphalt mixtures can be provided from the perspective of pores, interface adhesion, and asphalt mortar. Salt categories and erosion modes exerted great influences on the rheological performance of asphalt binders. The performance of different asphalt binders showed a remarkable diversity under salt erosion environments. In addition, the evolution of the chemical composition and microscopic morphology of asphalt binders under salt erosion environments can be well characterized by Fourier Infrared Spectroscopy (FTIR), Gel Permeation Chromatography (GPC), and microscopic tests. Finally, the major focus of future research and the challenges that may be encountered are discussed. From this literature review, pore expansion mechanisms differ fundamentally between conventional and salt storage asphalt mixtures. Sulfate ions exhibit stronger erosive effects than chlorides due to their chemical reactivity with asphalt components. Molecular-scale analyses confirm that salt solutions accelerate asphalt aging through light-component depletion and heavy-component accumulation. These collective findings from prior studies establish critical theoretical foundations for designing durable pavements in saline environments. Full article

Composite hydrogels with improved mechanical and chemical properties can be formed by non-covalently decorating the nanofibrillar structures formed by the self-assembly of peptides with fucoidan. Nevertheless, the precise interactions, and the electrochemical and thermodynamic stability of these composite materials have not been determined. Here, we present a thermodynamic analysis of the interacting forces that drive the formation of a composite fucoidan/9-fluorenylmethoxycarbonyl-phenylalanine-arginine-glycine-aspartic acid-phenylalanine (Fmoc-FRGDF) hydrogel. The results showed that the co-assembly of fucoidan and Fmoc-FRGDF was spontaneous and exothermic. The melting point increased from 87.0 °C to 107.7 °C for Fmoc-FRGDF with 8 mg/mL of added fucoidan. A complex network of hydrogen bonds formed between the molecules of Fmoc-FRGDF, and electrostatic, hydrogen bond, and van der Waals interactions were the main interactions driving the co-assembly of fucoidan and Fmoc-FRGDF. Furthermore, the sulfate group of fucoidan formed a strong salt bridge with the arginine of Fmoc-FRGDF. This study provides useful biomedical engineering design parameters for the inclusion of other highly soluble biopolymers into these types of hydrogel vectors. Full article

This study investigates the deterioration of granite graffiti at the Philae Archaeological Site on Bigeh Island (Aswan, Egypt), attributed to Khaemwaset (1281–1225 BCE, 19th Dynasty). These graffiti, despite being carved into durable Aswan granite, are experiencing progressive degradation due to environmental and hydrological factors. This research aims to analyze the mineralogical and chemical transformations affecting the graffiti to provide a comparative assessment of submerged and unsubmerged granite surfaces. A multi-analytical approach was employed, combining petrographical examination, X-ray diffraction (XRD), X-ray fluorescence (XRF), and scanning electron microscopy with energy-dispersive spectroscopy (SEM-EDS) to identify compositional changes and deterioration patterns. The results indicate mineralogical transformations in submerged and periodically exposed surfaces. The granite primarily consists of quartz, feldspar, and biotite, with notable alterations including kaolinization and illitization and dissolution of feldspar minerals and biotite oxidation. These processes are directly linked to prolonged exposure to fluctuating water levels and recurrent wet–dry cycles, which accelerate granular disintegration, exfoliation, and surface loss. Additionally, salt crystallization, particularly halite, contributes to granite weathering, while sulfate interactions promote chemical weathering. In addition, biofilm colonization, facilitated by high moisture retention, further exacerbates surface deterioration by producing organic acids that weaken the mineral matrix. Finally, the results confirm the need for conservation interventions to mitigate ongoing damage. Full article

Salt lakes and the surrounding saline soils distributed across northwestern China and Inner Mongolia impose severe physicochemical corrosion on cement-based concrete. Understanding the corrosion products and mechanisms are crucial scientific and technological factors in ensuring the durability and service life of concrete structures in these regions. In this study, various analytical techniques—including X-ray diffraction, thermogravimetric–differential thermal analysis, X-ray fluorescence, and scanning electron microscopy coupled with energy-dispersive spectroscopy—were employed to systematically analyze the corrosion products of ordinary Portland cement (OPC) and high-performance concrete (HPC) specimens after eight years of field exposure in the Qarhan Salt Lake area of Qinghai. The study provided an in-depth understanding of the physicochemical corrosion mechanisms involved. The results showed that, after eight years of exposure, the corrosion products comprised both physical corrosion products (primarily sodium chloride crystals), and chemical corrosion products (associated with chloride, sulfate, and magnesium salt attacks). A strong correlation could be observed between the chemical corrosion products and the strength grade of the concrete. In C25 OPC, the detected corrosion products included gypsum, monosulfate-type calcium sulfoaluminate (AFm), Friedel’s salt, chloro-ettringite, brucite, magnesium oxychloride hydrate 318, calcium carbonate, potassium chloride, and sodium chloride. In C60 HPC, the identified corrosion products included Kuzel’s salt, Friedel’s salt, chloro-ettringite, brucite, calcium carbonate, potassium chloride, and sodium chloride. Among them, sulfate-induced corrosion led to the formation of gypsum and AFm, whereas chloride-induced corrosion resulted in chloro-ettringite and Friedel’s salt. Magnesium salt corrosion contributed to the formation of brucite and magnesium oxychloride hydrate 318, with Kuzel’s salt emerging as a co-corrosion product of chloride and sulfate attacks. Furthermore, a conversion phenomenon was evident between the sulfate and chloride corrosion products, which was closely linked to the internal chloride ion concentration in the concrete. As the chloride ion concentration increased, the transformation sequence of sulfate corrosion products occurred in the following order: AFm → Kuzel’s salt → Friedel’s salt → chloro-ettringite. There was a gradual increase in chloride ion content within these corrosion products. This investigation into concrete durability in salt-lake ecosystems offers technological guidance for infrastructure development and material specification in hyper-saline environments. Full article

Bayan Obo rare earth concentrate (BOREC) is composed of bastnaesite, monazite and fluorite, which is recognized as a refractory mineral in the world. In order to solve the problems of waste gas treatment and comprehensive utilization efficiency of BOREC decomposed by the current concentrated sulfuric acid roasting method (500–700 °C), H₂SO₄-HCl mixed acid assisted by aluminum salt was used to leach out the bastnaesite, and the optimal conditions were determined as follows: c(H⁺) = 7 mol/L, c(1/2H₂SO₄):c(HCl) = 5:1, c(Al₂(SO₄)₃) = 0.25 mol/L, temperature 135 °C, liquid–solid ratio of 42:1, and reaction time 3 h. At this time, the leaching rates of concentrate and rare earth (La, Ce, Pr and Nd) were 74.08% and 71.95%, respectively, and the decomposition rate of bastnaesite was 96.83%. At the same time, the yield of calcium sulfate was 77.35% and the purity was 99.22%. Subsequently, sodium sulfate was added with m(Na₂SO₄):m(RE₂O₃) = 2.5:1, and the recovery rate of rare earth was 99.5%, and the purity of rare earth double salt product was 98.47% at a temperature of 90 °C. After most of the acid had been extracted with triethyloctanamine, sodium fluoride was added with a fluorine–aluminum ratio of 6:1, sodium carbonate was used to adjust pH = 3, and cryolite was obtained with a purity of 95.59% and an aluminum recovery rate of 99.6% at 90 °C. Since the separation of bastnaesite and monazite has been basically realized in the leaching stage, it is conducive to the docking of subsequent alkali decomposition and recovery of trisodium phosphate, realizing the comprehensive recovery of rare earth, fluorine, calcium, aluminum and phosphorus. Full article

A membrane system was applied for ultrapure water production from the treatment of saline effluent from the canned food industry. The industrial effluent presented a high saline concentration, including sodium chloride, calcium carbonate, calcium sulfates, and magnesium. The effluent was treated using a system of reverse osmosis (RO) and a post-treatment process consisting of ion exchange resins (IEXRs). The RO was accompanied by the addition of a hexametaphosphate dose (2, 6, and 10 mg/L) as an antiscalant to avoid the RO membrane scaling by minerals. In turn, IEXRs were used for water deionization to produce ultrapure water with a reduced concentration of monovalent ions. The antiscalant dose was 6 mg/L, producing clean water from RO permeates with an efficiency of 65–70%. The brine from RO was projected for its reuse in food industry processes. The clean water quality from RO showed 20% total dissolved solids (TDS) removal (equivalent to salts). The antiscalant inhibited the formation of calcium salt incrustation > 200 mg/L, showing low fouling. In turn, anionic resins removed 99.8% of chloride ions, whereas the monovalent salts were removed by a mix of cationic–anionic resin, producing ultrapure water with electrical conductivity < 3.3 µS/cm. The cost of ultrapure water production was 2.62 USD/m³. Full article

In milk, casein proteins orientate themselves into spherical micellar structures with hydrophobic casein subtypes concentrated in the core, while hydrophilic casein subtypes populate the exterior. Previous research demonstrated that milk with the addition of emulsifying salts coupled with high-pressure homogenization induced an unprecedented amount of casein micelle dissociation. This research aims to quantify the extent of casein micelle dissociation in diluted skim milk and evaluate the functionality of these proteins following emulsifying salt treatment coupled with high-pressure homogenization. To evaluate the extent of micellar dissociation, dilute skim milk solutions (20% v/v) were prepared with a varying amount of treatment: no processing (control), just emulsifying salts (Treatment E, 100 mM sodium hexametaphosphate), just high-pressure homogenization (Treatment H, at 300 MPa), and EH (a combination of E and H treatments). Samples were then put through varying filter sizes (0.22 µm, 0.05 µm), and the permeates were analyzed using sodium dodecyl sulfate-polyacrylamide gel electrophoresis. In the control group (20% skim milk), 9.35% ± 2.53% casein protein permeated through a 0.05 µm filter. Alternatively, 93.2% ± 7.71% casein protein was present in EH samples post-filtration through a 0.05 µm filter, demonstrating a significant processing-induced dissociation of casein micelles. A potential benefit to this casein micelle size reduction is the exposure of highly functional hydrophobic subunits from the core of the micelle. In agreement, compared to the control samples, the EH samples had higher foam expansion index values (138.3% ± 12.58% vs. 33.33% ± 14.43% at 0 h), foam stability (113.3% ± 5.774% vs. 21.67% ± 2.887% after 8 h), emulsifying activity (ca. two-fold higher), and interaction with caffeine. These data demonstrate that E, coupled with H, enhances skim milk system functionality, and these changes are likely due to micellar dissociation and protein conformational changes. This work has direct applications in dairy systems (e.g., dairy foams, dairy ingredients) as well as implications for potential processing strategies for other protein-rich systems. Full article

Salt-affected soil areas are increasing in the Northern Great Plains (NGP), with patches occurring in some of the most productive croplands. High electrical conductivity (EC) and sodium and/or sulfate concentrations of saline–sodic areas impede the growth and yield of ‘normal’ [corn (Zea mays)/soybean (Glycine max)] rotational crops, and more appropriate management systems are needed. Brassica spp. and amendment applications, such as biochar, may provide management alternatives for these areas. In two greenhouse studies, (1) 10 canola (Brassica napus) genotypes were evaluated for emergence in non-saline (EC_1:1 = 0.62 dS m⁻¹), moderately saline–sodic (EC = 5.17 dS m⁻¹), and highly saline–sodic (EC_1:1 = 8.47 dS m⁻¹) soils and (2) 10 canola genotypes and 3 other brassicas (Brassica juncea/B. oleracea) were evaluated for emergence and biomass in non-saline or moderately saline–sodic soils with or without two 5% biochar (hardwood or softwood) amendments. Canola emergence at 28 days after planting (DAP) in moderately and highly saline–sodic soils was less than 12% for most genotypes, although one had 37% emergence. The hardwood biochar improved Brassica spp. emergence (42%) from the moderately saline–sodic soil compared to non-amended soil (29%), although shoot biomass was similar among treatments at 60 DAP. These findings suggest that specific salt-tolerant Brassica spp. may be an alternative crop for NGP saline–sodic soil areas. Florida broadleaf mustard, typically used for forage, had the greatest emergence (52%) in the saline–sodic soil and may be a suitable cover crop for these areas. In addition, hardwood biochar applications may aid in plant establishment. Full article

This research examines the influence of ammonium (NH₄⁺) impurities on the kinetic behavior, activation energy, crystal structure, morphology, and purity of cobalt sulfate hexahydrate using the cooling crystallization method. Characterization results indicate that ammonium at all concentrations affects the crystallization process, with a minimum concentration required to alter crystal characteristics. At ammonium concentrations up to 3.75 g/L, the crystal growth rate decreases, while activation energy increases. Furthermore, the crystal structure does not change, and crystal purity decreases by approximately 0.2%. This decline is insignificant and tends to stagnate, suggesting a maximum adsorption limit of impurities onto the crystal. At ammonium concentrations of 5 g/L, the crystal growth rate increases, and activation energy decreases. This shift in behavior is caused by the formation of Tutton’s salt, (NH₄)₂Co(SO₄)₂·6H₂O, which significantly reduces crystal purity by 1%. Additionally, the presence of ammonium does not alter the crystal shape. Full article

Phycobiliproteins and pigments derived from cyanobacteria hold significant potential for diverse applications in the food, pharmaceutical, and chemical industries. The filamentous cyanobacterium Anabaena cylindrica serves as a valuable resource for extracting these compounds. This study develops a simplified, safe, and cost-effective extraction method that eliminates toxic solvents and minimizes processing steps. This makes the method applicable for all users and allows the easy integration of the extraction into biorefinery concepts in which the biomass is to be used as a fertilizer, for example. Utilizing salts such as ammonium sulfate and calcium chloride (15 gL⁻¹ each) enables the effective extraction of phycocyanin (PC) and allophycocyanin, achieving a PC concentration of 192.34 $\mathrm{mg}{\mathrm{g}}_{\mathrm{CDW}}^{-1}$ and 209.44 $\mathrm{mg}{\mathrm{g}}_{\mathrm{CDW}}^{-1}$, respectively. Ethanol was introduced as a less toxic alternative to methanol for pigment extraction, increasing chlorophyll a and carotenoid recovery by 21% and 37%, respectively. Full article

The water distribution system is a critical infrastructure aiming to deliver safe and clean drinking water, with pipeline materials significantly influencing water quality and efficiency. One critical factor in selecting pipeline materials is the potential for biofilm formation on the inner surfaces of pipes. This study investigates the effects of three iron salts—iron (II) sulfate heptahydrate, iron (III) nitrate nonahydrate, and iron (III) chloride on biofilm formation by Escherichia coli and Enterococcus faecalis in pipeline environments, focusing on water distribution systems. While previous research has examined the effects of iron on various bacterial species, there are limited data on E. coli and E. faecalis biofilm formation in the context of water distribution systems. Results reveal that iron (III) chloride significantly inhibited E. coli biofilm formation by up to 80%, while E. faecalis biofilm growth was promoted by iron (II) sulfate heptahydrate, with an increase of approximately 45%. These findings underscore the critical role of managing iron concentrations to mitigate biofilm-related issues, which influence water quality, infrastructure durability, and microbial resistance. The study highlights the importance of integrating these insights into sustainable water management practices and advancing pipeline material innovations to enhance public health and environmental resilience. Full article