Mineral Ions Research Articles

Effects of Mineral Salts on Chilled Canine Sperm Quality

Mineral ions have essential roles for maintaining osmotic balance, forming parts of primary enzymes relating to the sperm metabolism and function. This study was conducted to evaluate the effects of mineral salts as supplement to semen extender on chilled canine sperm quality during 10 days of storage. The sperm motility was performed by computer assisted sperm analysis (CASA). The plasma membrane integrity, acrosome membrane integrity, and mitochondrial membrane potential parameters were determined using a fluorescent staining combination. The results showed that although the percentage of sperm motility and sperm plasma membrane integrity in the mineral salts and the control extenders were not markedly different during the first 6 days of storage (P>0.05), the acrosome membrane integrity, mitochondrial membrane potential and the healthy sperm parameters in the mineral salts extender was substantially higher than that in the control extender during this period (P<0.05). Notably, the sperm quality of sperm in the mineral salts extender decreased rapidly after the first 6 days and evidently lower than that in the rest extender (P<0.05). In conclusion, the mineral salts extender can improve sperm quality in chilled canine sperm during 6 days of storage.

Functional Properties of Two Distinct PTH1R Mutants Associated With Either Skeletal Defects or Pseudohypoparathyroidism.

ABSTRACTConsistent with a vital role of parathyroid hormone (PTH) receptor type 1 (PTH1R) in skeletal development, homozygous loss‐of‐function PTH1R mutations in humans results in neonatal lethality (Blomstrand chondrodysplasia), whereas such heterozygous mutations cause a primary failure of tooth eruption (PFE). Despite a key role of PTH1R in calcium and phosphate homeostasis, blood mineral ion levels are not altered in such cases of PFE. Recently, two nonlethal homozygous PTH1R mutations were identified in two unrelated families in which affected members exhibit either dental and skeletal abnormalities (PTH1R‐V204E) or hypocalcemia and hyperphosphatemia (PTH1R‐R186H). Arg186 and Val204 map to the first transmembrane helix of the PTH1R, and thus to a critical region of this class B G protein‐coupled receptor. We used cell‐based assays and PTH and PTH‐related protein (PTHrP) ligand analogs to assess the impact of the R186H and V204E mutations on PTH1R function in vitro. In transiently transfected HEK293 cells, PTH1R‐R186H mediated cyclic adenosine monophosphate (cAMP) responses to PTH(1‐34) and PTHrP(1‐36) that were of comparable potency to those observed on wild‐type PTH1R (PTH1R‐WT) (half maximal effective concentrations [EC50s] = 0.4nM to 1.2nM), whereas the response‐maxima were significantly reduced for the PTH1R‐V204E mutant (maximum effect [Emax] = 81%–77% of PTH1R‐WT, p ≤ 0.004). Antibody binding to an extracellular hemagglutinin (HA) tag was comparable for PTH1R‐R186H and PTH1R‐WT, but was significantly reduced for PTH1R‐V204E (maximum binding level [Bmax] = 44% ± 11% of PTH1R‐WT, p = 0.002). The potency of cAMP signaling induced by a PTH(1‐11) analog was reduced by ninefold and threefold, respectively, for PTH1R‐R186H and PTH1R‐V204E, relative to PTH1R‐WT, and a PTH(1‐15) radioligand analog that bound adequately to PTH1R‐WT exhibited little or no specific binding to either mutant receptor. The data support a general decrease in PTH1R surface expression and/or function as a mechanism for PFE and a selective impairment in PTH ligand affinity as a potential PTH1R‐mutation‐based mechanism for pseudohypoparathyroidism. © 2022 The Authors. JBMR Plus published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research.

Mechanically reinforced injectable bioactive nanocomposite hydrogels for in-situ bone regeneration

Gelatin-methacryloyl (GelMA) has received extensive attention in tissue engineering because of its low antigenicity, suitable biodegradability, and similarity to ECM. However, it is still a challenge to induce in-situ bone regeneration for bone defects due to the absence of osteogenic factors or other mineral ions. In this study, a novel injectable organic–inorganic nanocomposite GelMA hydrogel system doped Sr-substituted xonotlite (Sr-CSH) nanofibers was developed. The integration of Sr-CSH nanowires improved the mechanical property of GelMA hydrogels. In addition, GelMA/Sr-CSH hydrogels facilitated cell adhesion, proliferation, ALP activity and the expression of osteogenic genes (BSP, OPN and OCN) and angiogenesis genes (VEGF, ANG-1 and CD31) by activating the ERK/p38 signaling pathway in vitro. Moreover, in vivo results of in-situ bone regeneration in rat calvarial defects model demonstrated that the incorporation of Sr-CSH nanowires could apparently accelerate new bone formation of GelMA. Overall, the prepared injectable organic–inorganic nanocomposite of GelMA/Sr-CSH hydrogel system has great potential for in-situ bone regeneration of bone defect area.

Novel process design of desalination wastewater recovery for CO2 and SOX utilization

Desalination is one of the most effective methods of supplying industrial water. Desalination has evolved into a feasible water supply alternative that allows the use of ocean water, and desalination plants operate in many countries, including in arid areas. Therefore, a large amount of desalination wastewater is generated, which is discharged into the sea. Since highly concentrated mineral ions in desalination wastewater are useful substitutes for carbon dioxide (CO2) and sulfur oxide (SOx) utilization compared with limited feedstock, such as high-grade limestone, it is crucial to improve the utilization of metal ions by recovering desalination wastewater. This study presents a novel process of desalination wastewater recovery CO2 and SOx utilization. The proposed process model comprises the following four systems based on validated experimental data: electrolysis, metal ion separation, SOx capture and utilization (SCU), and CO2 capture and utilization (CCU). First, desalination wastewater was electrolyzed to obtain a strong basic solution through electrolysis. Second, during metal ion separation, magnesium and calcium ions in the wastewater were precipitated in the form of a metal hydroxide and separated by the basic solution. Third, the separated Ca(OH)2 was used for desulfurization and produced gypsum in the SCU system. Finally, CO2 in the desulfurized flue gas was captured by the strong basic solution and utilized as CaCO3 and MgCO3 in the CCU procedures. Consequently, about 91% CO2 is captured and utilized from flue gas, and the desulfurization efficiency is 99%. In addition, the maximum net profit of the proposed process is $ 73.23 per tonne of CO2, and it is profitable and suitable for large-capacity processes, compared with other alternative CCU processes.

Property of mud and its application in cosmetic and medical fields: a review.

Mud is a semi-colloidal substance formed by the mixture of inorganic, organic and water under the influence of various physical and chemical factors through geological and biological processes. The chemical composition of mud is complex, rich in Ca2+, Zn2+, Mg2+, Na+ and other mineral elements, also contains organic matter such as humic acid, fulvic acid and acetic acid. In cosmetic field, mud can improve the activity of glutathione enzyme and superoxide dismutase in skin, which helps the skin anti-aging. Besides, it also can improve the skin microbial community, due to its distinctively physical properties, mineral ions, microorganisms, etc. In medical field, mud can treat osteoarthritis, especially knee osteoarthritis which has been studied extensively, and it can also increase the chemotaxis of macrophages. On the one hand, the use of clay (a kind of refined mud) can protect the gastrointestinal tract and treat some gastrointestinal diseases. On the other hand, clay is often used as carriers or composites in drug delivery, especially in skin drug delivery, showing very positive results. The purpose of this review is to present an overview of current knowledge about the application of mud in cosmetic and medical fields and to provide ideas for further research in mud.

Biomimetic Mineralized Hydroxyapatite Nanofiber-Incorporated Methacrylated Gelatin Hydrogel with Improved Mechanical and Osteoinductive Performances for Bone Regeneration.

PurposeMethacrylic anhydride-modified gelatin (GelMA) hydrogels exhibit many beneficial biological features and are widely studied for bone tissue regeneration. However, deficiencies in the mechanical strength, osteogenic factors and mineral ions limit their application in bone defect regeneration. Incorporation of inorganic fillers into GelMA to improve its mechanical properties and bone regenerative ability has been one of the research hotspots.MethodsIn this work, hydroxyapatite nanofibers (HANFs) were prepared and mineralized in a simulated body fluid to make their components and structure more similar to those of natural bone apatite, and then different amounts of mineralized HANFs (m-HANFs) were incorporated into the GelMA hydrogel to form m-HANFs/GelMA composite hydrogels. The physicochemical properties, biocompatibility and bone regenerative ability of m-HANFs/GelMA were determined in vitro and in vivo.ResultsThe results indicated that m-HANFs with high aspect ratio presented rough and porous surfaces coated with bone-like apatite crystals. The incorporation of biomimetic m-HANFs improved the biocompatibility, mechanical, swelling, degradation and bone regenerative performances of GelMA. However, the improvement in the performance of the composite hydrogel did not continuously increase as the amount of added m-HANFs increased, and the 15m-HANFs/GelMA group exhibited the best swelling and degradation performances and the best bone repair effect in vivo among all the groups.ConclusionThe biomimetic m-HANFs/GelMA composite hydrogel can provide a novel option for bone tissue engineering in the future; however, it needs further investigations to optimize the proportions of m-HANFs and GelMA for improving the bone repair effect.

Assessment of phenology, growth characteristics and berry composition in a hot Australian climate to identify wine cultivars adapted to climate change

Background and Aims The phenology, growth traits and fruit composition of cultivars in the CSIRO germplasm collection, located in a hot Australian region, were assessed to identify those adapted to climate change. Methods and Results The study involved 465 cultivars assessed over four seasons. Differences in key traits included a 5-week range in budburst; a 4-month harvest window; a twofold difference in the growth period from budburst to harvest; a fivefold difference in fruitfulness and in leaf area index; a 15-fold difference in berry mass; and a five- to 15-fold difference in berry mineral ion concentration and large differences in fruit composition. The latter included pH (range 3.48–4.95), titratable acidity (1.60–9.07 g/L), tartaric acid (2.20–7.95 g/L), malic acid (0.80–7.74 g/L), yeast assimilable nitrogen (70–505 mg/L) and, in red wine cultivars, total anthocyanins (0.04–5.79 mg/g) and phenolic compounds (0.55–3.60 a.u.). Conclusions Cultivars grown under hot conditions with late budburst to minimise frost risks; short growth periods and small canopies to improve water use efficiency; and early and late ripening to extend the season have been identified. Early ripening cultivars had better fruit composition than late ripening cultivars. Significance Opportunities to broaden genetic diversity will enhance the capability of the wine industry to meet challenges associated with climate change. Poor fruit composition, however, associated with high pH is a limiting factor under hot conditions.

Application of geostatistical techniques in the assessment of groundwater contamination in the Afigya Kwabre District of Ghana

Geostatistical techniques have been applied to successfully assess the groundwater quality in the Afigya Kwabre District of Ghana. Forty boreholes were sampled for physicochemical and bacteriological characteristics of the groundwater. Principal component analysis revealed that seven components contain 81.01% of the variation of the original variables. Factor 1 accounted for 31.34% of the total variance, factor 2 accounted for 10.97%, third and fourth factors explained 8.41% and 8.19%, the fifth factor showed 8.13% while the sixth and seventh components showed 7.76% and 6.21% variances, respectively. R-mode cluster analysis showed five clusters. Cluster 1 was made of Na+, Cl−, TH, SiO2, HCO3− and TDS. Cluster 2 and cluster 3 contained dissolved oxygen (DO), pH, K+ and F−, Br, respectively. Cluster 4 was made of PO43− and NO3−and Cluster 5 had Ca2+, Mg2+, Total. coli, Fecal. coli, SO42−, and salinity. Correlation analysis revealed a strong positive correlation between EC and TDS, Mg2+, Ca2+, Mn, Na+, TH, HCO3−; pH and Ca2+, HCO3−; Mg2+ and Ca2+, Na+, TH, HCO3−, Fe; Ca2+ and Na+, TH, HCO3−; Cu and PO43−; Mn and Na+; F− and SO42− as well as NO3− and PO43−. The study revealed the impact of both natural processes such as rock mineral weathering, ion exchange, and anthropogenic activities such as application of agrochemicals on farmlands and improper waste disposal on the geochemistry of the groundwater. Generally, the groundwater in the District has a low pH. However, it is generally suitable for domestic use with exception of a few samples with high Fe, F-, Pb concentrations and Escherichia coliform and fecal coliform contaminations. The study has shown that the geostatistical technique is useful in determining the state of water contamination, the extent of contamination, and possible source of contaminants, as well as presenting a guideline for effective groundwater resource management.

The power of weak ion-exchange resins assisted by amelogenin for natural remineralization of dental enamel: an in vitro study

This study aims to develop an innovative dental product to remineralize dental enamel by a proper combination of ion-exchange resins as controlled release of mineral ions that form dental enamel, in the presence of amelogenin to guide the appropriate crystal growth. The novel product proposed consists of a combination of ion-exchange resins (weak acid and weak base) individually loaded with the remineralizing ions: Ca2+, PO43− and F−, also including Zn2+ in a minor amount as antibacterial, together with the protein amelogenin. Such cocktail provides onsite controlled release of the ions necessary for enamel remineralization due to the weak character of the resins and at the same time, a guiding tool for related crystal growth by the indicated protein. Amelogenin protein is involved in the structural development of natural enamel and takes a key role in controlling the crystal growth morphology and alignment at the enamel surface. Bovine teeth were treated by applying the resins and protein together with artificial saliva. Treated teeth were evaluated with nanoindentation, scanning electron microscopy and energy-dispersive X-ray spectroscopy. The innovative material induces the dental remineralization creating a fluorapatite layer with a hardness equivalent to sound enamel, with the appropriate alignment of corresponding nanocrystals, being the fluorapatite more acid resistant than the original mineral. Our results suggest that the new product shows potential for promoting long-term remineralization leading to the inhibition of caries and protection of dental structures.

The long-term exposure of cyanotoxin, cylindrospermopsin, on the macrophyte Lemna trisulca

ABSTRACT The increase in frequency and prevalence of cylindrospermopsin (CYN)-producing cyanobacteria blooms have become a growing problem worldwide. Therefore, the long-term effects of CYN on the physiological processes of the macrophyte, Lemna trisulca, were examined. During a 5-day exposure to a range of CYN concentrations (0.5, 1 and 5 μg ml−1), the low levels of stress experienced by L. trisulca stimulated its growth rate and photosynthesis and led to an increase in the synthesis of photosynthetic pigments. In turn, it was shown that a 3-week exposure to the highest tested CYN concentration (5 μg ml−1) resulted in the inhibition of biomass accumulation (by 7.6%) compared with that of the control plants, but necrosis and chlorosis were not observed. A negative correlation with the concentration of carotenoids was also observed, which may suggest that the antioxidant mechanisms of L. trisulca are effective only up to a certain CYN concentration. An increase in protein content in the tissues of macrophytes treated with concentrations of CYN ranging from 0.5 to 5 μg ml−1 indicates that the toxin did not inhibit protein synthesis but increased the metabolism of L. trisulca, potentially to provide energy for defence. The toxin also affects the homeostasis of mineral ions in cells. This is the first description of the physiological response of L. trisulca to the long-term effects of a wide range of CYN concentrations.

Sonophotocatalytic degradation and operational parameters optimization of diazinon using magnetic cobalt–graphene nanocomposite as a catalyst

Adopting the hydrothermal method, the cobalt ferrite nanocomposite was loaded onto graphene (G–CoFe2O4) and the material thus produced was first characterized and then employed as a sonophotocatalyst to assist in the degradation of diazinon (DZN) at different operational parameters. Further, response surface methodology was used for the optimization and modeling of the operational parameters. From the statistical analysis of the analysis of variance (ANOVA), the quadratic model was observed to give a good fit with the experimental data, barring the catalyst dose (P value = 0.194) and the initial concentration of DZN (P value = 0.20), significantly affected the efficiency of the DZN degradation. Complete DZN degradation was achieved under the conditions of pH 3, time 100 min, DZN concentration 10 mg/L, temperature 50 °C, and the G–CoFe2O4 dose of 0.99 g/L. Reduction in the DZN degradation rate was observed, falling below 10% during the eight consecutive cycles, giving proof of the stability and adequate recyclability of the G–CoFe2O4. Biodegradability related to the five–day biochemical oxygen demand/chemical oxygen demand (BOD5/COD) ratio increased from 0.15 to 0.58, with the corresponding 90.95% total organic carbon (TOC) and 96.41% COD being removed. The toxicity evaluated using the inhibition growth rate of Escherichia coli (E. coli) showed high ability of the suggested treatment system to lower the toxicity, when compared to photocatalysis and photolysis. On using the analytical methods, the presence of the mineral ions such as NH4+, NO3−, SO42−, and PO43− appeared to act as good indicators of mineralization.

Advances in biomimetic mineralization of tooth enamel based on cell-free strategies

Tooth enamel is a highly-mineralized hard tissue covering the outermost layer of the dental crown, and amelogenesis is inseparable from the participation of necessary components such as ameloblasts, organic matrix proteins, and mineral ions, such as Ca2+ and PO43-. However, mature enamel is an acellular tissue and it is difficult to self-repair once damaged. The current treatment methods for enamel damage are filling or repairing with alloys, ceramics, or composite resins. However, the mechanical properties of these materials are quite different from the natural enamel and they can’t ensure a completely closed interface with the remaining enamel surface, which usually causes a series of post-repair problems. At present, the biomimetic mineralization of tooth enamel is a research hotspot in the field of prosthodontics, and has great clinical application needs and prospects, especially the researches on cell-free strategies have made significant accomplishment. Here, based on the cell-free strategies, we review the recent knowledge from ex situ and in situ two dimensions in the remineralization of tooth ename.

Chemical Compositions in Modified Salinity Waterflooding of Calcium Carbonate Reservoirs: Experiment

Modified or low-salinity waterflooding of carbonate oil reservoirs is of considerable economic interest because of potentially inexpensive incremental oil production. The injected modified brine changes the surface chemistry of the carbonate rock and crude oil interfaces and detaches some of adhered crude oil. Composition design of brine modified to enhance oil recovery is determined by labor-intensive trial-and-error laboratory corefloods. Unfortunately, limestone, which predominantly consists of aqueous-reactive calcium carbonate, alters injected brine composition by mineral dissolution/precipitation. Accordingly, the rock reactivity hinders rational design of brines tailored to improve oil recovery. Previously, we presented a theoretical analysis of 1D, single-phase brine injection into calcium carbonate-rock that accounts for mineral dissolution, ion exchange, and dispersion (Yutkin et al. in SPE J 23(01):084–101, 2018. https://doi.org/10.2118/182829-PA). Here, we present the results of single-phase waterflood-brine experiments that verify the theoretical framework. We show that concentration histories eluted from Indiana limestone cores possess features characteristic of fast calcium carbonate dissolution, 2:1 ion exchange, and high dispersion. The injected brine reaches chemical equilibrium inside the porous rock even at injection rates higher than 3.5 times 10^{-3} m s^{-1} (1000 ft/day). Ion exchange results in salinity waves observed experimentally, while high dispersion is responsible for long concentration history tails. Using the verified theoretical framework, we briefly explore how these processes modify aqueous-phase composition during the injection of designer brines into a calcium-carbonate reservoir. Because of high salinity of the initial and injected brines, ion exchange affects injected concentrations only in high surface area carbonates/limestones, such as chalks. Calcium-carbonate dissolution only affects aqueous solution pH. The rock surface composition is affected by all processes.

Zinc and its role in vitamin D function.

Zinc is an essential mineral with an important relationship with vitamin D. Studies have found that reduced blood zinc levels could predict vitamin D deficiency in adolescent girls, while zinc supplementation increased vitamin D levels in postmenopausal women. In vitro studies using human peritoneal macrophages have found that zinc induced the release of calcitriol (1,25-dihydroxycholecalciferol). Zinc also acts as a cofactor for vitamin D functions, as the transcriptional activity of vitamin D-dependent genes relies on zinc to exert pleiotropic functions, including mineral ion regulation. Vitamin D could also induce zinc transporters to regulate zinc homeostasis. Together, zinc and vitamin D in adequate concentrations help maintain a healthy musculoskeletal system and beyond; however, deficiency in either of these nutrients can result in various disorders affecting almost all body systems. This brief article will focus on the role of zinc in vitamin D functions.

Spatial Ionomics Reveals the Dynamic Network of Mineral Ions in Oryza Sativa L. Under Cd and Nutritional Deficiency Stress

Spatial Ionomics Reveals the Dynamic Network of Mineral Ions in Oryza Sativa L. Under Cd and Nutritional Deficiency Stress

An on-demand and on-site shape-designable mineralized hydrogel with calcium supply and inflammatory warning properties for cranial repair applications.

Although more than 2.2 million cranial repair surgical operations are performed every year, orthopedic doctors still dream of excellent artificial repair materials with suitable strength, on-site and on-demand fast-shaping properties, and bone induction properties. However, fast-shaping and high-strength properties seem to contradict each other, and even mineralized hydrogels, which already have excellent strength and bone induction properties, are not ideal candidates, since they lack the plasticity needed for complex craniofacial surface use during the essential mechanism of the process of the cleavage of inorganic ions, nucleation, and growth. Here, we report a novel mineralized hydrogel based on dispersing mineral ions prior to use and then inducing inorganic formation by decreasing the temperature, which endows the hydrogels with the characteristics of precise customization at an appropriate degree of mineralization and simultaneously achieves suitable mechanical properties and sufficient calcium supply for bone regeneration. Additionally, the calcium ion content in the water of the matrix will change with the temperature, and, thus, the conductivity of the mineralized hydrogels will change accordingly. This implements the ability to warn of inflammation in a timely fashion in the form of a temperature sensor. Therefore, this temperature-responsive hydrogel effectively achieves the aim of versatile material design.

A Review on Phytoconstituents and Therapeutic Properties of Ancient Plant: Terminalia arjuna (Roxb)

Terminalia arjuna also known as arjun or arjuna, is a member of Combretaceae family. Medicinal or therapeutic plant plays a crucial role to cure various diseases and Terminalia arjuna is one such therapeutic plant. This comprehensive review helps in studying various aspects like phytochemical, pharmacological, ethnomedical, phytological and clinical significance. Alkaloids, flavonoids, triterpenoids, glycosides and mineral ions present in different parts of the plant are discussed. Terminalia arjuna is used mainly in cardiovascular treatment, shows antibacterial, antimicrobial and antifungal properties.

Application of alternating electric field scale inhibition device in heat exchange station

The present study introduces an alternating electric field device that can effectively inhibit the growth of scale on industrial heat exchangers. The 5–70 V voltage and alternating electric field (AEF) of 80–300 kHz frequency are transferred by the device in water where they can inhibit scale formation on tube walls by changing the precipitation mode of mineral ions. After the alternating electric field device is used, the scale thickness on the heat exchange surface becomes significantly thinner, and the maximum fouling resistance decreases by 58% (from 8.54 10−4m2K/W to 3.58 10−4m2K/W). Scanning electron microscopy (SEM) results show that after the use of the alternating electric field device, the scale on the heat exchange surface changed from dense crystals with irregular, sharp shape to loose crystals with spherical shape, and X-ray diffraction (XRD) analysis showed that most crystals changed from calcite to aragonite. X-ray energy dispersion spectroscopy (EDS) analysis showed that the weight percentage of Fe in the scale decreased by 9.81%. This shows that scale and corrosion on the heat exchange surface can be effectively improved under the action of an electric field.

Traditional irrigation practices sustain groundwater quality in a semiarid piedmont

In semi-arid areas, agricultural practices have been found to significantly alter groundwater quality. Although significant research has been conducted on the impacts of the intensification of irrigated agriculture, many pivotal questions relating to the impact of traditional agricultural practices on groundwater quality remain unanswered. In this study, the results of major ions analysis of 91 water samples collected in the semi-arid piedmont of the High Atlas Mountains, central Morocco, are used to assess the impact of traditional irrigation practices on groundwater quality. Despite the use of organic fertilizer in the irrigated area, the NO3 groundwater concentrations remain low (median = 9 mg/L) and only increase on average by 3.6 mg/L during the irrigation season. All groundwater sampled in the irrigation area has an excellent quality for both drinking and irrigation purposes based on the chemical indices. Overall, groundwater chemistry is controlled by geogenic processes. Relationships between major ion in groundwater reflects the mineral dissolution and ion exchange processes during the trajectory of the streamwaters from the mountain to the alluvial plain via irrigation practices. In comparison, in the non-irrigated area, halite dissolution and/or transpiration processes results in increases in electrical conductivity values that were over twice the values in the irrigated area. The seasonal decrease of electrical conductivity values in groundwater beneath the irrigated area (on average from 841 to 692 μS/cm) is a result of irrigation recharge, which counterbalances effects of salinization mechanisms that can often characterize irrigated arid zones. These results highlight the low impacts of this ancestral hydro-agro system on groundwater quality. Such a traditional irrigation system provides a nexus between food production, low energy costs (streamflow diversions by gravity-fed channels), and low environmental impacts. In the context of accelerations in global change impacts via the rapidly expanding modern irrigation practices, such traditional hydro-agro systems, where possible, should be highlighted and preserved.

Direct contact membrane distillation with softening Pre-treatment for effective reclaiming flue gas desulfurization wastewater

Comparisons of the formation, distribution, and composition of the membrane foulants caused by raw and pre-treated flue gas desulfurization wastewaters during membrane distillation process. • Softening-treated DCMD for concentration of flue gas desulfurization wastewater. • Mineral ion is effectively removed by NaCO 3 , NaOH and polyacrylamide pre-treatments. • Pretreatment inhibits membrane fouling and changes composition of membrane fouling. • CaSO 4 is the main foulant. • Mg-Si, Al colloid and organic matter weld scaling layer. • Colloidal silica/organic matter is the main contaminant in DCMD to pre-treat FGDW. The flue gas desulfurization wastewater (FGDW) contains extremely high concentration of heavy ions (e.g., Ca 2+ , Mg 2+ ) and unbiodegradable organic pollutants such as humic substances. In this paper, the effects of softening pre-treatment on water reclamation performance and membrane fouling phenomenon of the direct contact membrane distillation of FGDW were investigated systematically. Results showed that fouling on the membrane caused by crystallization of CaSO 4 , Mg-Si complex, Al colloid, and organic matter in the FGDW decreased the permeate flux. Pre-treatment with NaCO 3 , NaOH and polyacrylamide in combination with coagulation and chemical precipitation processes resulted in nearly 100% removal of Ca 2+ and Mg 2+ and prevented membrane from fouling. This led to 11 times-concentrated FGDW with excellent salt and organic matter rejections. Overall, membrane distillation combined with softening pre-treatment can effectively reclaim FGDW water with high concentration and salt rejection rates, without causing significant membrane fouling.