Zeta Potential Tests Research Articles

Effect of Basalt Powder on Hydration, Rheology, and Strength Development of Cement Paste

Basalt materials (e.g., basalt powder, aggregate, and fiber) are commonly used in cement-based materials. To understand the mechanism of the influence of basalt on the properties of cement-based materials (i.e., fluidity, hydration, and strength), zeta potential tests with different Ca2+ concentrations were carried out using basalt powder (BP). It is found that BP has a weaker absorption for Ca2+ compared to cement and quartz particles, which is directly related to its surface chemical properties. This weak absorption has a significant influence on the rheology and early-age hydration of cement paste. Moreover, the morphology of hydrate on the surface of the material observed by scanning electron microscope (SEM) also shows that the growth of CSH on the surface of BP particles is smaller than that of cement particles, indicating that BP delays the formation of CSH. Rheological tests showed that the reduction of BP's adsorption of calcium ions weakened the electrostatic repulsion between particles, which led to the reduction of rheological properties. The influence of BP on the strength of cement paste was studied through crack characterization and fracture observation. The results show that the interfacial strength between BP and hydration products is very weak and does not increase with the hydration process, and the chemical reaction of BP is not obvious. In addition, the substitution of BP for cement leads to a dilution effect. These factors cause the strength of cement paste to decrease.

Selective flotation of pyrite from serpentine using phytic acid as the depressant

The flotation of sulfide minerals has been always a problem due to the slime coating of serpentine. In this study, phytic acid (PA) was introduced as a selective depressant to eliminate the adverse effect of serpentine on the flotation of pyrite. Micro-flotation tests showed that the flotation performance of pyrite depressed by serpentine could be regained with the addition of PA. In addition to micro-flotation tests, the action mechanism of PA was systemically investigated based on a series of analyses including zeta potential tests, adsorption measurements, turbidity studies and X-ray photoelectron spectroscopy (XPS) analyses. It was found that PA could chemically react with the active Mg sites and then selectively adsorb onto serpentine surface. In this case, the surface potential of serpentine was shifted from positive to negative at pH 9, thus resulting in the transformation of electrostatic interaction between pyrite and serpentine from electrostatic attraction to electrostatic repulsion. Hence, the slime coating of serpentine on pyrite surface was removed and the adsorption amount of potassium butyl xanthate (PBX) onto pyrite surface was regained. In this way, the adverse effect of serpentine on the flotation of pyrite was eliminated.

Flotation behaviors of chalcopyrite and galena using ferrate (VI) as a depressant

This paper investigated the effects of potassium ferrate (PF) on the flotation performances of chalcopyrite and galena. The flotation results showed that PF obviously depressed galena, but had little effects on the floatability of chalcopyrite within pH range of 4.0–12.0. Zeta potential tests showed that the addition of PF induced the formation of more amounts of hydrophilic species on the surface of galena under an alkaline environment. Industrial grade O-isopropyl-N-ethyl thionocarbamate (IPETC) chemically adsorbed on the surface of the PF-treated chalcopyrite and galena after its addition. Contact angle measurements showed that with the addition of PF, the contact angle of the galena surface significantly decreased compared with the chalcopyrite surface. Localized electrochemical impedance spectroscopy (LEIS) tests showed that the addition of PF increased the impedance of the galena surface. X-ray photoelectron spectroscopy (XPS) analyses revealed that the formation of hydrophilic species, namely lead sulfite, lead hydroxide and ferric hydroxide, on the galena surface, decreased its floatability in the presence of PF, while the formation of hydrophobic species, namely copper disulfide and elemental sulfur, on the chalcopyrite surface, maintained its floatability. Finally, a descriptive model for the reaction of PF with chalcopyrite and galena was proposed.

Verification of nanoparticle formation, skin permeation, and apoptosis using nobiletin as a methoxyflavonoid derivative

PurposeNobiletin (NOB), a polymethoxyflavonoid, is known for its antioxidant and anti-inflammatory effects and has antitumor activity. However, its poor solubility and low bioavailability pose a significant challenge in its delivery. In this experiment, NOB was added to Soluplus® (Sol)/l-ascorbyl 2,6-dipalmitate (ASC-DP) as a ternary system, and Sol/ASC-DP/NOB nanoparticles were obtained using the hydration method. The purpose of this study was to enhance the solubility of NOB, apply it for skin permeation, and improve antitumor activity.MethodsThe preparation of Sol/ASC-DP/NOB nanoparticles was attempted using the hydration method, and particle size, zeta potential, and stability tests were performed to evaluate the formation of nanoparticles. 1H-1H NOESY/ROESY NMR spectral measurements were also performed to identify molecular interaction between NOB and Sol/ASC-DP. To evaluate its functionality, DPPH radical scavenging, skin permeation, fluorescence microscopy, and cell viability analyses were performed.ResultsThe particles were approximately 100 nm in size in the ternary system (weight ratio (Sol/ASCDP/NOB=8/1/1)) and were relatively stable for approximately 7 days at 25 °C under light-shielded conditions. From the NMR spectrum measurements of Sol/ASCDP/NOB, a cross-peak was observed between the –OCH3 group: C6,8 (3.8 ppm) derived from NOB, the methyl group (2.0 ppm) derived from Sol, and the side chain portion (1.2 ppm) derived from ASC-DP. Cross-peaks were observed between the polyethylene glycol (PEG) backbone of Sol (3.6 ppm) and the side chain of ASC-DP (0.8–1.2 ppm). The formation of Sol/ASC-DP/NOB nanoparticles facilitated its skin permeation, and fluorescence microscopy confirmed improved permeation. The DPPH radical scavenging test revealed that Sol/ASC-DP/NOB had an IC50 of 46.7 μg/mL. Cell viability assays showed a 20–40% decrease in cell viability with the addition of Sol/ASC-DP/NOB at 0.1 mg/mL.ConclusionSol/ASC-DP/NOB nanoparticles were successfully prepared, and these were found to inhibit melanin formation and have antitumor activity.

FORMULATION AND CHARACTERIZATION OF ZEAXANTHIN NANOEMULSION RADIANCE SERUM AS ANTIOXIDANT

Objective: This study aimed to increase the effectiveness of using zeaxanthin by developed nanoemulsion containing zeaxanthin which was then formulated into radiance serum for topical use.
 Methods: Nanoemulsions are made using spontaneous nano emulsification methods/techniques, which are relatively simple technologically because they rely on the right combination of selected surfactants and co-surfactants. The optimization of the formula was carried out starting from determining the oil: surfactant: co-surfactant phase ratio and concentration of zeaxanthin. Nanoemulsion characterization in the form of physical characterization includes organoleptic tests, globule size and polydispersity index, zeta potential, pH and entrapment efficiency tests. The best results from nanoemulsion were then combined into serum preparations which were then tested for evaluation of the preparations, including organoleptic, homogeneity, viscosity, pH, spreadability, and antioxidant test.
 Results: The results showed that the developed zeaxanthin nanoemulsion had a globule size in the range of 20-24 nm (with a normal globule size distribution curve), polydispersity index value of less than 0.3, zeta potential greater than (-20) mV and entrapment efficiency ranging from 80-85%.
 Conclusion: The results of the evaluation showed that the serum radiance of zeaxanthin nanoemulsion had good physical, chemical and stability properties during storage with an IC50 value of zeaxanthin less than 50 ppm.

FORMULATION AND CHARACTERIZATION OF FACIAL SERUM FROM ASTAXANTHIN-BETA CAROTENE NANOEMULSION AS AN ANTIOXIDANT

Objective: The purpose of this study is to make facial serum from astaxanthin-beta carotene nanoemulsion as an antioxidant.
 Methods: Nanoemulsions were prepared using Spontaneous Nanoemulsion (SNE) method with a ratio of 1:8:1 for (Sunflower oil): surfactant (Kolliphor® RH40): and co-surfactant (PEG 400). Physical nanoemulsion characterization includes globule size, polydispersity index, zeta potential, visual appearance, pH and entrapment efficiency test. The best results from nanoemulsion were then combined into serum preparations which were then tested for evaluation of the preparations, including organoleptic, homogeneity, viscosity, pH, adhesion and stability test (cycling test).
 Results: The results showed that the nanoemulsion of astaxanthin and beta-carotene combination that had been developed had a globule size of<50 nm (with a normal globule size distribution curve), polydispersity index value was less than 0.5, zeta potential was greater than-20 mV and entrapment efficiency was ranging from 80-85%. The results of the preparation evaluation showed that serum astaxanthin-beta carotene nanoemulsion had good results in physical, chemical and stability test during storage. The best serum formula is formula 3 when viewed from the results of the evaluation of the dosage form with an IC50 value of 8.562 ppm with a very strong category as an antioxidant.
 Conclusion: Facial serum from astaxanthin-beta carotene is the potential to be an antioxidant.

The synthesis and characterization of core-shell nanogels based on alginate and chitosan for the controlled delivery of mupirocin

This study aims to synthesize alginate-coated chitosan (ACC) and chitosan-coated alginate (CCA) nanogels as core-shell nanostructured carriers incorporated with mupirocin as an antibiotic. Characterizations are determined by FESEM, TEM, EDS, DLS, zeta potential, and FTIR followed by in vitro release study and MTT assay. The FESEM images show an almost spherical structure as well as a proper uniformity with an average diameter of 16.5 ± 0.95 nm and 17.84 ± 2.3 nm for ACC and CCA nanogels, respectively. FTIR spectra show probable interactions between components. The DLS test finds the particle dispersity index of ACC and CCA is 0.57 and 0.05, respectively, which means CCA presents more uniform dispersion. According to the nature of biopolymers, the surface charges of ACC nanogels are negative compared with positive ones of CCA nanogels confirmed by the zeta potential test. After loading mupirocin, an increase in size is observed. Besides, about 96 % of the antibiotic is released from Mupirocin (0.15 %)-loaded-CCA at 72 hrs while it is about 70 % for Mupirocin (0.15 %)-loaded-ACC nanogels. The antibacterial test exhibits good antibacterial properties against both gram-positive and gram-negative bacteria. Finally, MTT assay approves the biocompatibility of the produced nanogels. Overall, CCA and ACC nanogels would be promising substrates in a controlled drug delivery system.

Enhanced Efficacy of Radiopharmaceuticals When Using Technetium-99m-Labeled Liposomal Agents: Synthesis and Pharmacokinetic Properties.

Challenges posed by the retention of radiopharmaceuticals in unintended organs affect the quality of patient procedures when undergoing diagnostics and therapeutics. The aim of this study was to formulate a suitable tracer encapsulated in liposomes using different techniques and compounds to enhance the stability, uptake, clearance, and cytotoxic effect of the radiopharmaceutical. Cationic liposomes were prepared by a thin-film method using dipalmitoyl phosphatidylcholine (DPPC) and cholesterol. Whole-body gamma camera images were acquired of intravenously injected New Zealand rabbits. Additionally, liposomes were assessed using stability, toxicity, zeta potential, and particle size tests. In the control cases, Technetium-99m (99mTc)-sestamibi exhibited the lowest heart uptake the blood pool and delayed images compared to both 99mTc-liposomal agents. Liver and spleen uptake in the control samples with 99mTc-sestamibi increased in 1-h-delayed images, unlike with 99mTc-liposomal agents, which were decreased in delayed images. The mean maximum count in the bladder for 99mTc-sestamibi loaded liposomes 1 h post-injection was 2354.6 (±2.6%) compared to 178.4 (±0.54%) for 99mTc-sestamibi without liposomes. Liposomal encapsulation reduced the cytotoxic effect of the sestamibi. 99mTc-MIBI-cationic liposomes exhibited excellent early uptake and clearance compared to 99mTc-MIBI without liposomes. Adding cholesterol during liposome formation enhanced the stability and specificity of the targeted organs.

Effect of Zeolite Content on Permeability of Stone Chip-Bentonite-Zeolite Mixture Using a Single Solution

Bentonite is frequently utilized as a landfill lining material due to its high impermeability. Due to the fact that heavy metal ions in leachate can alter the permeability of bentonite liner, the impermeability and metal adsorption effect of bentonite liner is typically enhanced by the use of external admixtures. In this investigation, zeolite was combined with stone chips and bentonite. Using a flexible wall permeation test, zeta potential test, and X-ray diffraction test, the effect of zeolite on the permeability and adsorption properties of the mixture was investigated. The results indicate that the addition of zeolite can enhance the impermeability of the mixed soil. The permeability coefficient of the mixed soil in DIW is 3.74 × 10−7 cm/s when bentonite is incorporated at 11% and decreases to 6.55 × 10−8, 4.65 × 10−8, and 5.10 × 10−8 cm/s when 12.50%, 25%, and 50% of zeolite are incorporated; the permeability coefficient of the mixed soil in DIW was 3.74 × 10−7 cm/s when the permeate concentration was 0.01 mol/L of ZnCl2 solution, the permeation coefficients were 5.73 × 10−7, 5.98 × 10−8, 5.8 × 10−8, and 5.7 × 10−8 cm/s when the zeolite doping was 0, 12.50, 25, or 50%, respectively, and the Zn2+ concentration of the leachate decreased compared to the no-zeolite case by 92.48, 97.29, and 98.65%, respectively; the competitive adsorption of metal ions by zeolites in ionic solutions of different concentrations reduced the ionic concentration in the solution and decreased the inhibition of bentonite swelling, while the adsorption characteristics of stone chip-bentonite-zeolite mixture on Zn2+ were measured by the Langmuir and Freundlich et al. model.

NiTi-layered double hydroxide as an efficient photocatalytic fungicide of Aspergillus fumigatus spores: Capacity and mechanism

Eliminating dormant spores of Aspergillus fumigatus (A. fumigatus) with robust cell wall and super hydrophobicity is a formidable challenge and has attracted great attention. Herein, we found that NiTi-layered double hydroxide (NiTi-LDH) exhibited remarkable photocatalytic inactivation against A. fumigatus dormant spores (∼104 ​CFU/mL), the killing rate could reach to 91.6% after 6 ​h visible light irradiation, which was reusable. Zeta potential test showed that NiTi-LDH possessed positively charged while spores presented negatively charged, which promoted their interaction through electrostatic adsorption, and this was also confirmed by SEM. It not only overcame the problems of low affinity caused by hydrophobicity, and short action distance of photo-generated active species because of their extremely short lifetime, but also weakened spore via interfering with its normal metabolism. In addition, NiTi-LDH exhibited wonderful visible light absorption and excellent photogenerated carrier's separation. Therefore, under the synergy of positive charge disruption and active species oxidation, the dormant spores were severely damaged and died. This work might provide enlightenment for selection and design of recyclable photocatalyst to efficiently and greenly remove pathogenic microorganisms under visible light.

Surface Properties of Eggshell Powder and Its Influence on Cement Hydration.

Using eggshell powder (EP) to replace partial cement in cement-based materials can abate pollution caused by eggshell discard and cement production. In this paper, the surface property of EP and its influence on cement hydration were studied. Quartz powder (QP) and limestone powder (LP) were used as references. First, the chemical composition of EP was characterized. Then, the surface charge properties of these materials were analyzed using zeta potential measurement. The interactions between EP surface and Ca2+ were discussed based on the zeta potential test. Afterward, a scanning electron microscope (SEM) was applied to observe the morphology of hydrates on the surfaces of these materials. The results indicated that, although the compositions of EP and LP are similar, the surface charge properties are significantly different. This is likely due to the existence of organic matter on the surface of EP and the difference in the atomic structure. As shown from the zeta potential test, EP exhibits similar interaction with Ca2+ as QP. The interactions between EP surface and Ca2+ are much weaker than that between LP and Ca2+. These weak interactions lead to the growth of C-S-H on the surface of EP particles less than that of LP particles. The chemical reactivity of EP can be improved by using heat treatment, electrical oven, etc. This study will provide theoretical support for the better use of EP in cement-based materials.

Effect of Compounding Retarder and PCE on the Early Properties and Hydration of High-Belite Sulphoaluminate Cement

To cope with the problem that the setting time and hardening time of high-belite sulphoaluminate cement (HBCSA) is too fast and not easily controlled, three common retarders, citric acid (CA), β-cyclodextrin (β-CD), and borax (B), were selected and compounded with polycarboxylate superplasticizer (PCE). Based on the cement slurry fluidity, fluidity loss, setting time, and mechanical properties of cement mortar, combined with X-ray diffraction (XRD), scanning electron microscopy (SEM), and Zeta potential tests, the interaction and mechanism of different retarders and high-belite sulphoaluminate cement were studied. The results show that β-CD and CA can significantly delay the hydration process of HBCSA cement, effectively improve the fluidity loss, and make the dispersion more stable, but the strength of cement mortar decreases, which is not conducive to the development of strength. However, the addition of B has no obvious retarding effect on the HBCSA cement, and the dispersibility of the cement paste decreases. In microscopic tests, XRD and SEM tests verified that the combination of retarder and PCE had a certain inhibitory effect on the early hydration of HBCSA, and the zeta potential indicated that the addition of retarder would interact with PCE to improve the fluidity loss of HBCSA. In addition, when the retarders CA and B were, respectively, compounded with β-CD, the two would have a synergistic effect. The retardation effect is more obvious, and the time interval between the initial and final setting is shorter, which is more controllable. The initial fluidity is also improved under the auxiliary plasticization of cement paste by β-CD.

New insights into the combination of Fe(III) and xanthan gum in dewatering of coal slurry: Molecular self-assembly

Aggregation is an economical and widely existing method to in fine coal particles dewatering, but the effect of cations on the flocculation activity of different bio-flocculant was inconformity. In this work, the aggregation behavior of coal slurry using XG combination Fe3+ was investigated. The adsorption of FeCl3·6H2O and XG was investigated via wetting heats, water contact angle, Zeta potential and SEM-EDS testing. The results show that the combination of FeCl3·6H2O and XG could build up layer-by-layer self-assembly multilayers on coal particles surface. Further, solution chemistry, FTIR and XPS analyses were performed to detect the adsorption mechanism. The results indicate that Fe(OH)3(s) covering and coordination reaction of the Fe active sites with the polar groups of XG are the main driving force for the self-assembly. The obtained settling tests results show a great potential of the combination of XG combination Fe3+ in the dewatering of coal slurry. The flocculation dewatering model of coal with FeCl3·6H2O and XG was drawn.

Preparation and adsorption properties of green cellulose-based composite aerogel with selective adsorption of methylene blue

Four green aerogels were prepared to remove the cationic dye methylene blue (MB), using the method of solution mixing and freeze-drying. Polyethylene glycol diglycidyl ether (PEGDE) was employed as a crosslinker. The structure and performance of the adsorbents were analyzed by scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), X-ray diffraction (XRD), Fourier transform infrared (FT-IR), zeta potential measurement and mechanic testing. The results identified that PEGDE efficiently assisted in forming network structure of the porous aerogels, and the removal rates of four aerogels were all higher than 90%. The aerogel composed of sodium carboxymethyl cellulose (CMC) and carboxylated cellulose nanofibers (CNF–C) performed best with adsorbance of 579.50 mg/g, which had a strong electrostatic attraction with MB, exhibited selective adsorption, and did not collapse after ten cycles of underwater compression tests. The adsorption process of CMC/CNF–C aerogel was compatible with the pseudo-second-order kinetic model and Langmuir isothermal model, and the maximal adsorption capacity was 917.43 mg/g. According to the calculation of thermodynamic parameters, the adsorption process was spontaneous and benefited from temperature rise in 20–40 °C. After five regenerations, the adsorption capacity of CMC/CNF–C aerogel decreased from 579.5 mg/g to 513.2 mg/g, indicating a reusable adsorbent in wastewater treatment.

Rheology and thermal conductivity of graphene oxide and coal fly ash hybrid nanofluids for various particle mixture ratios for heat transfer applications: Experimental study

This work presents the synthesis of graphene oxide (GO) and coal fly ash (CFA) nanoparticles (NP) to produce water base mono and hybrid nanofluids (HNF) for different particle mixture ratios of 50:50 and 30:70. X-ray diffraction analysis (XRD), X-ray fluorescence (XRF), dynamic light scattering analysis (DLS), Fourier transform infrared (FTIR), field emission scanning electron microscope (FESEM), Ultraviolet-visible spectroscopy analysis (UV–Vis), and zeta-potential tests were carried out. The non-ionic surfactant polyvinylpyrrolidone (PVP) is added to the nanofluid (NF) to improve stability. The thermal conductivity (TC) and rheology experiments are carried out for the concentration range of 0.1 to 1.0 vol% in the temperature range of 30 to 60 °C. The results show that TC and viscosity (VST) enhancement of GO NF is higher than the studied HNF. The maximum VST enhancement of 177%, 152%, and 113% are observed for GO, and GO/CFA (50:50) and, GO/CFA (30:70), respectively for a concentration of 1 vol% at 30°C relative to water. Based on the obtained data, regression analysis is formed to estimate the TC and VST of the studied HNF. The performance enhancement ratio (PER) results show that GO NF and HNF with a mixture ratio of 30:70 are beneficial for thermal applications at all temperatures, whereas HNF with a mixture ratio of 50:50 is only at 45°C and above.

Effectiveness of nano-cobalt oxide with manufactured plant extract and its properties on inhibiting the growth of some types of bacteria and fungi isolated from skin infections

The prepared cobalt oxide nanoparticles were manufactured in the first and second methods, and they show the properties of the nanomaterials for all solutions of plant extracts. XRD examination showed (440) 65, (622) 79, while Sem's examination showed the appearance with a size of 10-25 nm. Tem examination gave that nanoparticles with a size not exceeding 0.5-60 nm. The UV absorbance and permeability test indicated that the nanomaterial is at a value between 236-800nm, and energy gap values of 2.0-3.8 ev. Ft-ir assay shows that the bonding sites for cobalt oxide are at (±50) (505 to 694), and the Zeta Potential test indicated that all the particles of the solutions have very small values and that the material is not agglomerating. The Aleo vera plant extract with cobalt oxide nanomaterial, where the diameters of the inhibition zones were (35, 35, 45) mm, respectively, for the growth of both Ps.aeruginosa, S. aureus and E.coli bacteria. The results of the effect of cobalt oxide solutions on the inhibition of the growth of fungi were great, and that the nanomaterial was also sweeping, showing the absence of fungal growth Trichophyton mentagrophytes.

Impact of PAM-ZnO nanocomposite on oil recovery

A new nanocomposite (NC) comprising of ZnO nanoparticles and polyacrylamide (PAM) polymer hybrid agent is investigated for enhanced oil recovery in sandstone and carbonate rocks. A range of measurements are conducted to examine the behavior of NCs including NC synthesis and characterization, NC physical properties, stability analysis, IFT, and wettability as a function of NC concentration (from 100 to 1000 ppm). Furthermore, core flood tests are performed to evaluate oil recovery and relative permeability characteristics and a numerical model is established, and history matched.The zeta potential tests verified the stability of the set NC at 200 ppm concentration in water-based solutions, while a clear reduction in IFT from 29 mN/m to 5.5 mN/m was observed at the same NC concentration. A notable shift is observed in contact angle from 133° to 13° for the sandstone rock at a 1000 ppm NC concentration suggesting a significant shift in wettability from oil-wet to strongly water-wet after NC injection while the optimal contact angle for the sandstone occurred at NC concentration of 200 ppm. Furthermore, the flooding NCs resulted in a 16.05 % increase in oil recovery factor compared to seawater flood for sandstone while a 26 % increase was recorded for carbonate sample. Likewise, the mobility ratio after NC flooding compared to seawater flooding decreased from 8.56 to 1.46. We obtained a good history match of the water cut and oil recovery factor data by creating the core dimension model. In addition, according to the fluid distribution pattern (one of the simulator outputs), the fingering phenomenon was delayed after flooding the NC compared to seawater. This study provides new insights into the impact of nanocomposite on oil recovery enhancement in sandstone and carbonate formations.

Surface properties of ceramic waste powder and its effect on the rheology, hydration and strength development of cement paste

To reduce carbon emissions and environmental impacts, ceramic waste powder (CWP) can be used to replace part of the cement in concrete. To understand the mechanisms of the influence of CWP on the properties (i.e. rheology, hydration and strength) of cement-based materials, a zeta potential test with different Ca2+ concentrations was conducted. It was found that CWP has a similar absorption for Ca2+ as cement and quartz particles, which is directly related to its surface chemical properties. The adsorption of Ca2+ on the particle surface affects the formation of C–S–H and the rheology of the cement paste. Based on the similarity in surface chemistry, it is elucidated that the effect of CWP on the rheology and early-age hydration of cement paste is attributed to its size or shape, not the surface chemical properties. In addition to strength measurement, the effect of CWP on the strength of cement paste was investigated by crack characterization and fracture surface observation. The results demonstrated that as hydration proceeded the interface strength between CWP and hydrates increased, and the chemical reaction of CWP became apparent. It also showed that CWP is an inert filler similar to quartz particles at early age. Nevertheless, at late age the pozzolanic reaction becomes obvious and improves the strength development of the cement paste.

Polyvinyl alcohol and sodium alginate hydrogel coating with different crosslinking procedures on a PSf support for fabricating high-flux NF membranes

Polyvinyl alcohol (PVA) and sodium alginate (SA) hydrogel-coated nanofiltration (NF) membranes with high-flux and permselectivity were prepared. The coating of PVA and SA hydrogel selective layer on a porous polysulfone (PSf)/non-woven fabric ultrafiltration substrate membrane was conducted through different three procedures including pre-crosslinking, in-situ crosslinking, and immersing crosslinking and the use of glutaraldehyde as a crosslinking agent. The properties and performances of all types of the prepared membranes were evaluated through ATR-FTIR spectroscopy, AFM, SEM, zeta potential, contact angle, and cross-flow permeation tests. The immersing technique resulted in the formation of TFC membranes with higher hydrophilicity, smoother surface layer, higher negative charge, higher permeation flux, higher salt rejection and better anti-fouling performance. Also, the higher negative surface charge of the immersing coated TFC membranes due to dissociation of hydrophilic functional groups of the PVA and SA hydrogel selective layer resulted in higher As(III) rejection. SA coated NF membrane through immersing method exhibited a higher pure water permeability of 11.2 L m−2 h−1 bar−1, NaCl, MgSO4, and Na2SO4 rejection of 38.2%, 55.1%, and 70.4%, respectively with As(III) rejection of 60.6%. All types of the PVA and SA hydrogel-coated PSf membranes possessed improved fouling resistance to BSA aqueous solution, superior anti-fouling performance was obtained with SA hydrogel coating through immersing method. Such optimum membranes indicated high stability in the long-term experiments. This study showed that the coating of the SA hydrogel layer on a PSf support through immersing method could be a promising candidate for fabricating high-flux NF membranes.

Effectiveness of nano-nickel oxide with manufactured plant extract and its properties on inhibiting the growth of some types of bacteria and fungi isolated from skin infections

Nickel oxide nanoparticles prepared in the first and second methods were synthesized and the properties of the solutions were shown. The XRD examination according to the MT values was at the drawing amount (111) 37.2, (200) 44.6, (220) 62.5 corresponding to the international measurements of Miller's Theta2 coefficient, while it was Sem examined the appearance of the shape of the rocky, cork, or spherical and spherical particles with a size of 10-25 nm, the TEM examination gave that nanoparticles with a size not exceeding 0.5-40 nm, the UV test of absorbance and permeability indicated that the solution is homogeneous and very light and the nanomaterial is at a value between 236-800 nm and indicates Energy gap values are 2.0-5.6 ev and that the material is semiconductive, which is evidence of the presence of nickel oxide. The Ftir test shows that the bonding sites for cobalt oxide are at 500-600, and the zeta Potential (ZP) test indicates that all solutions have very small values and that the material is not agglomerating and very light.