Effect of zinc oxide on synthesis of magnesium potassium phosphate cement

Simple SummaryWeaning is a stressful period for pigs that causes gastrointestinal disruption and low growth rates. For a long time, zinc oxide at pharmacological doses, along with different antibiotics, has been used prophylactically during this phase to reduce the incidence of these gastrointestinal problems. Nowadays, the increasing concern about the environment, along with the global and constant growth of bacterial resistance to antibiotics, has led to the prohibition of the prophylactic use of zinc oxide in diets for piglets in the EU, along with the implementation of new regulations on the use of antibiotics. Consequently, the pig sector faces the important challenge that supposes developing alternatives to the classical system based on the use of these antimicrobial compounds. This study is the first step to achieving this goal by minimizing the use of various antibiotics and zinc oxide in weanling pigs by supplementing citrus flavonoids and only one antibiotic (amoxicillin). Accordingly, the influence of zinc oxide plus antibiotics and citrus flavonoids plus amoxicillin in weaned pigs has been investigated and its impact on growth performance, gut microbiology profile, gut signaling, intestinal architecture, and serum biomarkers indicative of stress and inflammatory responses have been evaluated. Citrus flavonoids plus amoxicillin improved growth performance and gut health, evidencing a positive microbial modulation, stress status reduction, and a positive effect on the gastrointestinal barrier, and other digestive functions. Additionally, the expression of some bitter taste receptors in the intestine has been increased when supplementing both dietary strategies, the one based on zinc oxide or the one based on citrus flavonoids supplementation. Consequently, the present study shows that in weanling piglets, the supplement of citrus flavonoids with amoxicillin might be a promising alternative to the dietary use of pharmacological doses of zinc oxide with more than two antibiotics, therefore minimizing the use of antimicrobial compounds without detrimental effects on performance.Since citrus flavonoids have antioxidant and anti-inflammatory properties, it was hypothesized that these compounds would become a suitable alternative to the use of therapeutic doses of zinc oxide at weaning. A total of 252 weaned pigs ([LargeWhite × Landrace] × Pietrain) were distributed according to BW (5.7 kg ± 0.76) into 18 pens (6 pens per diet, 14 pigs/pen). Three experimental diets for the prestarter (0–14 d postweaning) and starter (15–35 d postweaning) period were prepared: (i) a nonmedicated (CON) diet, (ii) a CON diet supplemented with zinc oxide at 2500 mg/kg, amoxicillin at 0.3 mg/kg and apramycin at 0.1 mg/kg (ZnO), and (iii) CON diet with the addition of a commercial citrus flavonoid extract at 0.3 mg/kg and amoxicillin at 0.3 mg/kg (FLAV). Pig BW, ADG, ADFI, and FCR were assessed on d7, d14, and d35. Samples of intestinal tissue, cecal content, and serum were collected on day seven (18 piglets). FLAV treatment achieved greater BW and ADG during the starter and for the entire experimental period compared with the CON diet (p < 0.05), whereas ZnO pigs evidenced intermediate results. Jejunum tissue analysis showed that pigs fed the FLAV diet overexpressed genes related to barrier function, digestive enzymes, and nutrient transport compared to those pigs fed the CON diet (p < 0.05). An increase in the abundance of bacterial genera such as Succinivibrio, Turicibacter, and Mitsuokella (p < 0.05) was observed in the FLAV compared with the CON and ZnO piglets. ZnO and FLAV increased the expression of TAS2R39, while ZnO pigs also expressed greater TAS2R16 than CON (p < 0.05) in the intestine. FLAV treatment improved the gut function, possibly explaining a higher performance at the end of the nursery period. Consequently, citrus flavonoids supplementation, together with amoxicillin, is a promising alternative to the use of zinc oxide plus amoxicillin and apramycin in weanling pigs, minimizing the use of antibiotics.

Organic acids are increasingly being investigated as alternatives to zinc oxide (ZnO) in nursery pig diets. Monoglycerides can act in distal parts of the intestine, promoting intestinal health, also reducing bacterial fermentation in hindgut. This study aimed to determine the effects of dietary supplementation based on a blend of monoglycerides (C4:C8:C10) (MBLEND) in replacement to ZnO during the nursery phase on growth-performance and intestinal health. Ninety-six piglets were used (average weight 7.08 ± 0.837 kg) with 25 days of age during 42 days, divided into three treatments and eight replicates in a randomized block design. The treatments were: CON - Negative control (basal diet without additive supplementation); MBLEND - Fatty acids (basal diet with monoglycerides blend (C4:C8:C10) additive supplementation at 1.5 kg/ton in the pre-initial 1 and pre-initial 2 phases, 1.0 kg/ton in the initial 1 and initial 2 phases) and ZnO - Zinc oxide (basal diet with zinc oxide supplementation at 3000 ppm in the pre-initial 1, pre-initial 2 and initial 1 phases, 2000 ppm in the initial 2 phase). Both ZnO and MBLEND groups did not influence (P>0.05) growth performance during all phases. The inclusion of the MBLEND improved (P<0.05) dry matter (DM), crude protein (CP), and ashes digestibility when compared to CON and ZnO groups. The use of ZnO reduced (P<0.05) IL-1 β cytokine expression in the piglets' jejunal mucosa. ZnO increased evenness and affected beta-diversity (P<0.05) compared to CON and MBLEND. The ZnO group increased Tannerellaceae, Bacteroidaceae, and Muribaculaceae families and reduced Escherichia Coli-Shigella and Desulfovibrio generas (q<0.05). Although there were similar results on growth performance, ZnO modulated cecal microbiota and reduced inflammatory ileal cytokines and MBLEND improved protein and ashes digestibility.

The use of supplementary cementitious materials as partial Portland cement substitutes in concrete is one of the best strategies for reducing carbon dioxide (CO2) emissions in the cement industry, and also improves the properties of concrete. When highly reactive calcined pozzolans such as metakaolin are used, the setting time of concrete is reduced, and the use of retardants is necessary. The effect of zinc oxide (ZnO) as a cement hydration retarder has already been investigated; however, the influence of zinc oxide on ternary mixtures is unknown and needs study. In this research, the effect of adding zinc oxide on the hydration, microstructure and compressive strength of ternary mixtures is studied using setting time and compressive strength tests, X-ray diffraction, Fourier transform infrared spectroscopy, thermogravimetric analysis with differential scanning calorimetry and scanning electron microscopy. The results show that the hydration process of ternary pastes is delayed or even inhibited when the amount of zinc oxide in the paste is increased. With the addition of 0.5 wt.% zinc oxide, the initial setting time and compressive strength of ternary mixtures after 3 days of curing are similar to those of the cement paste without the addition of pozzolans and zinc oxide.

Effect of zinc oxide (ZnO) nanoparticles (NPs), manganese dioxide (MnO2) NPs and their blends on the yield and quality of bioethanol produced from cofermentation of banana and potato wastes has been investigated. Thus, in this study, ZnO, MnO2 NPs and their novel blend were synthesized, characterized and employed as additives to the fermentation processes, and their effects on the yield and quality of bioethanol produced from various blends of the organic wastes were evaluated. Potato peels (PP) and banana peels (BP) were collected and prepared for sample characterization. Prepared samples were then pretreated using acid pretreatment method before enzymatic hydrolysis, cofermentation and products analyses were carried out. Series of experiments were carried out using the feedstock blends: 100 wt.%BP: 0 wt.%PP, 30 wt. %BP: 70 wt.%PP, 70wt.%BP: 30 wt.%PP, 50 wt. %BP: 50 wt.%PP and 0 wt. %BP: 100 wt.%PP. The ZnO, MnO2 and ZnO+MnO2 NPs were added to the feedstock blends, and the blends without nanoparticles served as control samples. Study results unveiled that the highest yield of bioethanol (29.72g/l) was obtained from the sample blend, 100wt%BP + 0wt.%PP treated with ZnO NPs, and this was followed by 28.52g/l of bioethanol obtained from 50wt.%BP + 50wt.%PP sample blend treated with ZnO and ZnO +MnO2 NPs. It was also observed that the amount of bioethanol produced from addition of ZnO NPs to samples is higher than those produced from control samples as well as from samples treated with MnO2 and ZnO +MnO2 NPs. This may be because ZnO acts as a better catalyst, positively enhancing the enzymatic activity which accelerates the conversion of sugars into ethanol than MnO2 NPs. Product analysis results further unveiled the effect of the nanoparticles on the quality of bioethanol produced. Results of this study could enhance sustainability and economic viability of bioethanol production from organic wastes using nanoparticles.

Zinc oxide is a safe source of zinc for all animal species and no concerns for consumer safety are expected from the use of zinc oxide in animal nutrition, considering the maximum contents for total zinc in feedingstuffs set by EU legislation. Zinc oxide is not an irritant to skin and eyes; it is not a skin sensitiser. The zinc oxide under application is considered a compound with high dusting potential, which may result in a critical exposure of users by inhalation, affecting the respiratory system. The authorised use of zinc oxide as a feed additive does not pose a direct concern for the agricultural soil compartment. However, there is a potential environmental concern related to groundwater, drainage and the run-off of zinc to surface water. Acid sandy soils are most vulnerable to these processes. In order to draw a final conclusion, some further refinement to the assessment of zinc-based feed additives in livestock needs to be considered, for which additional data would be required. The use of zinc-containing additives in aquaculture up to maximum authorised zinc level in feeds is not expected to pose an appreciable risk to the environment. Zinc oxide is efficacious in meeting animal zinc requirements.

Oven aging properties at 350° F and 300° F of EPT polymers were substantially improved with additions of zinc oxide up to 10 and 20 phr. Zinc oxide enhanced the elongation retention after aging, and the improvement was significantly greater with French than with American Process zinc oxides. Finer particle size French Process zinc oxides imparted somewhat better aging properties than did the coarser zinc oxides of the same type. The aging advantage for high loadings of zinc oxide was notable both with whiting and clay-filled EPT compounds with low and normal amounts of sulfur. When the pigmentation of the EPT polymer was 50 phr of FEF black, the aging differences between the several American and French Process oxides at loadings of three to 20 phr were less prominent. Replacement of three per cent of EPT with an equal amount of several unsaturated elastomers increased the cure rate of the compound appreciably. Tear resistance was improved and compression set properties lowered. Improvement in heat resistance depends on the polymer added. Several anatase and rutile pigments were essentially equal in heat aging resistance at an equal volume loading in EPT. The reflectance of stocks with zinc oxide alone or in combination with titanium dioxide in an unfilled stock increased during the first three days of Atlas Weather-Ometer exposure. Beyond this point, there was a gradual degradation in reflectance with the loss in reflectance being somewhat greater with a zinc oxide-titanium dioxide blend than straight zinc oxide. These results reflect the observed differences in ultraviolet opacity between zinc oxide and titanium dioxide. In a comparison of anatase and rutile in a whiting loaded stock, anatase was poorer than rutile in reflectance through the initial exposure stages in the Atlas Weather-Ometer; however, after prolonged exposure, there was a reversal in reflectance, due to the chalk layer developed in the anatase sample. EPT stocks pigments with 79.5 phr of whiting with titanium dioxide between 18.5 and 25 phr, and activation amounts of zinc oxide showed no visible sunlight degradation after 70 weeks outdoors.

1. Zinc oxide and stearic acid do not affect the rate of addition of sulfur to rubber in the vulcanization of pure sodium butadiene rubber in mixtures without accelerators. 2. In mixtures containing diphenylguanidine as accelerator zinc oxide and stearic acid do not affect the rate of addition of sulfur to rubber. 3. In mixtures containing mercaptobenzothiazole zinc oxide retards and stearic acid accelerates the addition of sulfur to rubber. 4. In a similar manner zinc oxide suppresses and stearic acid activates isotope exchange between elementary sulfur and sulfur of the thiol group in mercaptobenzothiazole. 5. Zinc oxide and stearic acid in mixtures with mercaptobenzothiazole increase the rate and degree of crosslinking of the molecular chains of rubber; zinc oxide has the greater influence on the degree, while stearic acid has the greater influence on the rate, of the crosslinking reaction. 6. In mixtures with diphenylguanidine the influence of vulcanization activators on the degree and rate of crosslinking is considerably less pronounced than in mixtures with mercaptobenzothiazole. 7. The kinetics of zinc sulfide formation during vulcanization has been studied and it was established that ZnS is formed as the result of reactions of zinc oxide and zinc compounds with thiol and polysulfide groups in the rubber. Model substances have been used to demonstrate other possible routes for the formation of zinc sulfide during vulcanization. The effect of zinc oxide and stearic acid on the rate and degree of crosslinking is associated with participation of these compounds in such reactions. 8. Isotope exchange between radioactive sulfur in the vulcanizate and elementary sulfur was used to follow the formation and changes in the numbers of polysulfide linkages during the vulcanization process. The amount of sulfur participating in isotope exchange as vulcanization proceeds at first increases, passes through a maximum, and then decreases, which indicates a regrouping of the polysulfide linkages with an increase in their number and a decrease of the average number of sulfur atoms per linkage. Zinc oxide decreases the degree of isotope exchange between the vulcanizate and elementary sulfur at all stages of vulcanization. 9. Vulcanization activators, by favoring a decrease in the number of sulfur atoms in the sulfur bonds, increase the heat stability of the vulcanizates. This effect of the activators was demonstrated by kinetic data on stress relaxation in deformed vulcanizates at 126°. 10. The cleavage and regrouping of polysulfide linkages in the presence of zinc oxide and zinc compounds is accompanied by the combination of part of the sulfur as zinc sulfide, which leads to a decrease in the number of newly formed crosslinks. This effect of zinc oxide is manifested in vulcanization reversion effects and in changes of vulcanizate properties under thermomechanical influences. 11. From the above experimental data the general conclusion may be drawn that the fundamental role of vulcanization activators does not lie in their influence on the kinetics of the addition of sulfur to rubber, but rather in their influence on the nature of the vulcanization structures formed and on changes in them in the course of vulcanization.

Evaluating the efficiency of functionalized zinc oxide based curing system for polychloroprene composites and analyzing its effect on curing, physical, and morphological properties for the application in specialty power transmission belts

Aim: The present study aimed to describe the use of zinc oxide in a public healthcare organization in Riyadh Region.&#x0D; Methodology: This is a retrospective study that includes reviewing the electronic prescriptions of zinc oxide among outpatients in a public healthcare organization in Riyadh Region.&#x0D; Results: More than 52% of the patients who received zinc oxide were males and the age of 79.41% of them was less than 10 years. More than 55% of the patients received zinc oxide for 1 week and 17.65% of them received zinc oxide for 2 weeks. All of the prescriptions were prescribed by residents (100.00%). Most of the prescriptions were written by emergency department (76.47%).&#x0D; Conclusion: The present study showed that zinc oxide was uncommonly prescribed in Al-Kharj. Additional studies are needed to explore the frequency of and the pattern of using it in different settings.

Carboxyl groups in elastomer molecules have been shown to contribute to the crosslinking or joining of these molecules through hydrogen bonding, salt formation, reaction with diepoxides or polyepoxides including epoxy resins, reaction with diamines or polyamines, esterification with di- or poly-hydric alcohols, reaction with carbodiimides, reaction with polyimines, and by reaction with polyisocyanates. Each of these reactions alone may produce useful crosslinkages. Or, they may be used in conjunction with crosslinking reactions operating in other parts of the molecule such as sulfur or peroxide vulcanization. This has been particularly true of salt formation, especially through the use of zinc oxide, with sulfur vulcanizarions. The carboxyl groups in some instances may be generated during the crosslinking reaction. Thus polyethylacrylate may be crosslinked with hexamethylene diamine, barium hydroxide and similar reagents. Many of the reactions of the carboxyl groups in elastomers are quite rapid. For some purposes such as surface toughening of elastomer films, this may be quite useful. For others such as the vulcanization of carboxylic elastomers with zinc oxide or with recipes containing zinc oxide, this may be objectionable because of the scorchiness of the stocks. The scorchiness of vulcanizates of carboxylic elastomers involving zinc oxide may be controlled with organic acid additives or by the use of zinc oxide coated with less reactive materials such as zinc sulfide or zinc phosphate. The speed of reaction of epoxides with carboxyl containing polymers is influenced by the structure of the epoxide. The ease with which carbodiimides induce crosslinkage is dependent upon the structure of the carbodiimide.

The interface between the active layer and the charge-transporting layer is critical for performance improvement in polymer solar cells (PSCs). The use of zinc oxide (ZnO) as an electron transport layer (ETL) in PSCs was limited due to inherent defects in the surface of ZnO prepared by the sol-gel method, mismatched energy bands with the photoactive layer, and incompatibility between the photoactive layer and ZnO ETL. In this study, nitrogen and phosphorus codoped carbon dots (N &amp; P-CDs) were prepared from Ensete ventricosum (false banana) and used as an interfacial modification layer for ZnO ETL. The inverted devices with structures ITO/ZnO/N &amp; P-CD/PTB7:PC70BM/Al were fabricated to investigate the charge transfer dynamic between the active layer and ETL interface modification with N &amp; P-CDs. We have observed that the interfacial modification between the ZnO ETL and the active layer, using N &amp; P-CDs, improves the charge transfer between ZnO ETL and PTB7:PC70BM active layer. The obtained result shows that the ETL/BHJ interface resistance of the devices with ZnO:undoped CDs, ZnO:N-CDs, ZnO:P-CDs, and ZnO:N &amp; P-CD ETLs decreases dramatically from 103.4 to 84.04, 78.16, 37.88, and 28.9 Ω, respectively. This is due to the improvement of charge extraction efficiency by smoothing ZnO surface defects and minimizing the band mismatch between the active layer and ZnO using N &amp; P-CDs. The results indicate that the water-soluble N &amp; P-CDs developed in this study have the potential to be used for efficient free charge carrier extraction for PSCs.

In this study, the effects of zinc oxide (ZnO) and silver (Ag) nanoparticles (NPs) on the intestinal bacteria, Escherichia coli, Lactobacillus acidophilus, and Bifidobacterium animalis were investigated. All three bacterial strains were inoculated into tryptic soy broth (TSB) or Lactobacilli MRS broth media containing different concentrations of ZnO (0, 12, 16, 20 mM) and Ag (0, 1.8, 2.7, 4.6 mM) NPs and 1% of NP-free solution and incubated at 37 oC for 24 h. The presence and characterization of ZnO and Ag NPs on bacterial cells were investigated by scanning electron microscopy (SEM), transmission electron microscopy (TEM), and energy-dispersive X-ray spectroscopy (EDS). UV-visible absorbance and the Live/Dead Bacterial Viability assay were performed to assess membrane leakage and viability of bacterial cells before and after treatment with the NPs. For all bacteria, for up to 12 h of incubation, the numbers of treated cells were within 1 log CFU/mL less than that of the control. Morphological changes of bacterial cells were observed, but many cells remained in normal shapes. Results of UV-visible spectroscopy showed that only a small amount of internal cellular contents were leaked due to the NPs. Also, more live than dead cells were observed after exposure to the NPs. Results indicate that ZnO and Ag NPs have very mild inhibitory effects on intestinal bacteria.

Zinc oxide (ZnO) has been used at pharmacological levels to promote gut health and growth performance in the critical postweaning (PW) phase of piglets. The pharmacological use of ZnO in piglet diets has been banned in Europe and other countries due to antimicrobial resistance and environmental concerns. Therefore, understanding its mode of action, including its molecular mechanisms, is crucial for developing effective and sustainable alternatives. We investigated the mechanisms by which dietary supplementation with 3,000 mg/kg ZnO supports gut health and improves growth performance of piglets during the first 14 days PW. During the 2 weeks of trial (0–14 d PW), ZnO fed piglets had higher average daily gain (165 vs. 123 g/d; p < 0.01), and tended to have increased average daily feed intake (204 vs. 181 g/d; p < 0.1) and improved gain-to-feed ratio (0.669 vs. 0.774; p < 0.05) compared to control piglets. Feces from piglets in the ZnO group were also more consistent during the 2 weeks of trial (p < 0.01). At day 14 PW, ZnO piglets had lower calprotectin concentrations in serum (p < 0.01). Dietary ZnO downregulated several genes, involved in immune, oxidative and inflammatory responses, in jejunal (GPX2, REG3G, IL-8, IL-6, IL-22, and TGFβ1) and ileal (REG3G, IL-17A, IL-1β, and TLR2) mucosa (p < 0.05). It also downregulated the expression of the zinc transporter SLC39A4, that is associated with zinc homeostasis, in both tissues. Notably, PPARGC1A, which promotes energy production and lipid metabolism through fatty acid oxidation, was upregulated by ZnO in ileum. In conclusion, the current results suggest that high dietary levels of ZnO reduce the expression of inflammatory cytokines, the oxidative enzyme GPX2, pathogen recognition proteins, and zinc transporters while promoting the expression of PPARGC1A gene related with energy metabolism in the intestine. Therefore, ZnO can facilitate a smoother weaning transition to reduce weaning related gut health disturbances, ultimately contributing to gut homeostasis and improved performance.

The zinc alkaline battery is one of the most popular sources of portable electrical energy, with more than 300,000 tons being consumed per year. Accordingly, it is critical to recycle its components. In this work, we propose the use of zinc oxide (ZnO) microparticles recovered from worn-out batteries as fillers of epoxy resins. These nanocomposites can be used as protective coatings or pigments and as structural composites with high thermal stability. The addition of ceramic nanofillers, such as ZnO or/and TiO2, could enhance the thermal and mechanical properties, and the hardness and hydrophobicity, of the epoxy resins, depending on several factors. Accordingly, different nanocomposites reinforced with recycled ZnO and commercial ZnO and TiO2 nanoparticles have been manufactured with different nanofiller contents. In addition to the different ceramic oxides, the morphology and size of fillers are different. Recycled ZnO are“desert roses” such as microparticles, commercial ZnO are rectangular parallelepipeds nanoparticles, and commercial TiO2 are smaller spherical nanoparticles. The addition of ceramic fillers produces a small increase of the glass transition temperature (<2%), together with an enhancement of the barrier effect of the epoxy resin, reducing the water diffusion coefficient (<21%), although the maximum water uptake remains constant. The nanocomposite water absorption is fully reversible by subsequent thermal treatment, recovering its initial thermomechanical behavior. The water angle contact (WCA) also increases (~12%) with the presence of ceramic particles, although the highest hydrophobicity (35%) is obtained when the epoxy resin reinforced with recycled flowerlike ZnO microparticles is etched with acid stearic and acetic acid, inducing the corrosion of the ZnO on the surface and therefore the increment of the surface roughness. The presence of desert rose ZnO particles enhances the de lotus effect.

ObjectivesThis study aimed to synthesize nanocrystals (NCs) of zinc oxide (ZnO) and calcium ion (Ca2+)-doped ZnO with different percentages of calcium oxide (CaO), to evaluate cytotoxicity and to assess the effects of the most promising NCs on cytotoxicity depending on lipopolysaccharide (LPS) stimulation.Materials and MethodsNanomaterials were synthesized (ZnO and ZnO:xCa, x = 0.7; 1.0; 5.0; 9.0) and characterized using X-ray diffractometry, scanning electron microscopy, and methylene blue degradation. SAOS-2 and RAW 264.7 were treated with NCs, and evaluated for viability using the MTT assay. NCs with lower cytotoxicity were maintained in contact with LPS-stimulated (+LPS) and nonstimulated (−LPS) human dental pulp cells (hDPCs). Cell viability, nitric oxide (NO), and reactive oxygen species (ROS) production were evaluated. Cells kept in culture medium or LPS served as negative and positive controls, respectively. One-way analysis of variance and the Dunnett test (α = 0.05) were used for statistical testing.ResultsZnO:0.7Ca and ZnO:1.0Ca at 10 µg/mL were not cytotoxic to SAOS-2 and RAW 264.7. +LPS and −LPS hDPCs treated with ZnO, ZnO:0.7Ca, and ZnO:1.0Ca presented similar NO production to negative control (p > 0.05) and lower production compared to positive control (p < 0.05). All NCs showed reduced ROS production compared with the positive control group both in +LPS and −LPS cells (p < 0.05).ConclusionsNCs were successfully synthesized. ZnO, ZnO:0.7Ca and ZnO:1.0Ca presented the highest percentages of cell viability, decreased ROS and NO production in +LPS cells, and maintenance of NO production at basal levels.