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Many domestic items of clothing and military application use polyester as their main fiber content. It has low flame retardancy therefore it is required to add a flame retardant finish. In this study, the flame retardant finish was synthesized using magnesium hydroxide as the core and melamine cyanurate as the shell. Magnesium hydroxidewas chosen as the main material since it is claimed an environmental-friendly flame retardant substance. The verticalflame test was conducted and the samples were characterized by a scanning electron microscope (SEM). The results showed the flame retardant finish could hinder the flame to burn the polyester fabric until 30 % of the fabric length. It was also found that the microcapsules spread all over the surface, but the size and the placement were still uneven. [ABSTRACT FROM AUTHOR]

Currently, the advantages and disadvantages of antimony compounds, halogen-containing compounds, phosphorus preservatives, as well as aluminum and magnesium hydroxides have been studied and analyzed. Various mechanisms for slowing down combustion processes are considered. Containing flame retardants have been shown to be more effective than chlorinated flame retardants. They decompose in a short temperature range. In addition, the composition contains fire-resistant plastics, which are easily recycled due to their high heat resistance. [ABSTRACT FROM AUTHOR]

Orphaned or abandoned sulphide tailing disposal sites pose significant environmental hazards, including eolian dispersion, water erosion, acid mine drainage, and heavy metal mobility. Phytostabilization, an eco-friendly strategy, entails the use of alkaline amendments alongside non-native plant species capable of thriving in environments with high concentrations of heavy metals. A greenhouse experiment was conducted to assess the effect of a commercial cement which contained 46.3% sand, applied alone or combined with three magnesium (Mg) reagents on the shoot dry yield (DMY) of ryegrass (Lolium multiflorum Lam.) grown on sulphide mine tailings (SMT) (pH 3.0). The 29 treatments evaluated were replicated three times in a randomized complete block design. All pots received N-P-K fertilizer. Treatments combining cement and Mg reagents significantly increased the pH of the cultivated tailings. Magnesium oxide (MgO) and magnesium hydroxide (Mg(OH)2), when mixed with the cement, were more effective than magnesium carbonate (MgCO3) in maintaining alkaline conditions in the cultivated tailings. The pH increase was notably higher in cultivated tailing samples treated with cement+MgO, reaching pH levels ranging from 4.93 to 7.58. Analysis of variance (ANOVA) revealed a highly significant effect of the cement+Mg reagents on the DMY of ryegrass. There was a strong correlation between substrate pH and DMY (r = 0.853, p < 0.001), with a quadratic regression equation providing the best fit to the data (R² = 0.894, p < 0.001). In conclusion, the study highlights the potential of an 8% cement combined with 2% MgO for tailing revegetation or cultivation purposes. [ABSTRACT FROM AUTHOR]

Microbiologically induced corrosion (MIC) leads to the degradation/deterioration of concrete pipes, due to the formation of gypsum. Magnesium hydroxide powders may protect the concrete surface by maintaining alkaline pH values at the surface, or by neutralizing the biogenic produced sulfuric acid. An accelerated sulfuric acid spraying test in a custom-made spraying chamber used to examine the consumption of magnesium hydroxide coating, which was applied on poly (methyl methacrylate) plates, instead of applying it on concrete substrates. In that way, only the magnesium hydroxide coating can interact with the acid and can be examined separately. Surface pH measurements and the mass changes were daily conducted, during the four-day accelerated spraying test. The mineralogical phases of the surface were determined by using X-ray Diffraction (XRD) measurements. [ABSTRACT FROM AUTHOR]

Plant-based green synthesis approach is increasingly popular because of its simple process, cost-effectiveness, environmental friendly nature, expandability to commercial level, efficiency in large-scale synthesis, and flexibility in utilizing various value-added products. This work focuses on the synthesis and characterization of nano-size MgO prepared using water-soluble compounds extracted from different parts of Moringa oleifera plant, including woody vascular, the bark of woody, twigs, and leaves. To examine the efficacy of the aqueous extracts as a reducing agent and stabilizing agent, they were mixed with magnesium chloride solution, followed by addition of NaOH solution to form precipitate of magnesium hydroxide. The progress of the reaction was followed by UV-Vis spectrophotometric technique. The precipitate was calcined at 600 ℃; for 5 h, and then characterized using various techniques include XRD, SEM, TEM, and PSA. The formation of MgO as nano material, with the particle size in the range of 40 to 100 nm was confirmed by characterization techniques employed. Successful production of nano-size MgO achieved in this study demonstrates that M. oleifera plant is a prospective source of green agents for production of nano-size materials. [ABSTRACT FROM AUTHOR]

Despite significant advances in medicine, the development of new drugs for cancer treatment remains an urgent task. Only in the last 10 years the number of patients with cancer has increased several times. Therefore, it is advisable to look for new ways to fight against cancer. To solve this problem, new nanotechnology advances and various systems based on nanoparticles are used. One of antitumor treatments may be the use of nanostructured composites based on MgO/Mg2Al(OH)7. In this work, these nanostructures were obtained by water oxidation of an electric explosive nanopowder of AlN/Al composite in the presence of magnesium chloride solution. The effect of synthesized nanostructures on the viability of tumor cells Neuro-2a was studied. MgO/Mg2Al(OH)7 nanostructures have been shown to exhibit more pronounced antitumor activity than magnesium hydroxide both alone and in combination with the chemotherapeutic drug doxorubicin. [ABSTRACT FROM AUTHOR]

The study of thermal behaviors of magnesium hydroxide before and after modifying by high energy electron beam irradiation demonstrated that the initial temperature of mass loss of the irradiated sample is lower than that of the sample without irradiation. Moreover, the quantities of released water and carbon dioxide gas of irradiated specimen are also higher than these values of non-irradiated one. The DSC results showed that the endothermic effects of decomposition reaction of irradiated sample are stronger than that of the sample without irradiation. It was found that magnesium hydroxide particles size greatly decreased, from 74,2 µm of the non-irradiated sample to 33,9 µm at the irradiation dose of 40 kGy. [ABSTRACT FROM AUTHOR]

Nanoceramic hydroxides are important functional materials which hold enormous potential to host important applications. Here we report synthesis and characterization of nano magnesium hydroxide. These hydroxides are synthesized by a very simple and inexpensive aqueous chemical route using two different precursors. The structural, morphological, optical and vibrational properties of the powders were evaluated by conventional characterization techniques and were compared with each other. The morphology having porous nanostructure assemblies with vacant channels as seen here may provide high surface area eventually offering themselves for future technological applications. [ABSTRACT FROM AUTHOR]

Mg(OH)2 and MgO nano particles having flake, like morphology have been synthesized using hydrothermal method. XRD pattern revealed the formation of hexagonal phase for Mg(OH)2while cubic phase for MgO. SEM images shows the transformation of morphology from nanoflakes to nanoballs like shape upon change in crystal structure from hexagonal Mg(OH)2 tocubic MgO. Thermal decomposition and percentage weight loss were calculated through thermogravimetric analysis (TGA) and it is inferred that defects related to oxygen vacancies are responsible for the magnetic properties and the origin of d0 ferromagnetism in these non-magnetic oxides. [ABSTRACT FROM AUTHOR]

In this study, a novel modifier (PPD-PTES) for Magnesium Hydroxide (MH) was successfully synthesized from (3-Aminopropyl) triethoxysilane and phenylphosphonic dichloride aiming to improve not only the compatibility of MH with polymer but also its efficiency. Fourier transform infrared spectroscopy (FTIR), ¹H, 31P-nuclear magnetic resonance (NMR) were carried out to characterize its structure. The flammability, thermal degradation and mechanical properties of the PLA/MH composites were investigated by limiting oxygen index (LOI), microscale combustion calorimetry (MCC), thermogravimetric analysis (TGA) and tensile test. The results showed that the introduction of MH can significantly reduce the peak of heat release rate (PHRR) and total heat release (THR). Additionally, the LOI of modified MH reinforced PLA has also increased compared to the unmodified MH reinforced PLA. Further, results of tensile test proofed that the organic modification could improve the compatibility of MH with the polymer, but only slightly decrease brittleness. [ABSTRACT FROM AUTHOR]

Magnesium oxide and magnesium sulfate were known to react with water to form magnesium hydroxide and magnesium hydroxide heptahydrate. Thermal energy was released during the reaction, and the formed product can be decomposed reversibly when heat is applied. They can be used as thermochemical heat storage materials because of high reaction enthalpy and reversibility. In this study, magnesium oxide was formed into honeycomb shape so that the high temperature air for heat storage or low temperature humid air could be passed through flutes of the honeycomb with minimum pressure drop. Mechanical and thermal properties of the prepared honeycombs were measured and discussed. [ABSTRACT FROM AUTHOR]

The paper is devoted to describing how boehmite, magnesium hydroxide and calcium hydroxide nanoparticles in the form of nanoplates with a size of 20-200 nm having cytotoxic properties to tumor cells were synthesized. It is shown that calcium hydroxide has the highest cytotoxicity, while boehmite has the lowest one. The characterization of the synthesized nanostructures demonstrated that the major antitumor factors probably are the acid-base surface properties. It is established that calcium hydroxide raises the pH of the cell culture medium up to 12.8, magnesium hydroxide--up to 10.8, boehmite--up to 8.6. At the same time, synthesized nanoplates are less toxic to the normal cell lines. The approach presented can be used for synthesis of materials that are able to change tumor cells microenvironment acidity in the defined range for anticancer therapy, and also potentiating standard chemotherapy drugs effect due to extracellular acidosis decreasing. [ABSTRACT FROM AUTHOR]

A series of Cu doped magnesium hydroxide fluoride, Mg1-xCuxFOH, were synthesized via sol-gel method followed by vacuum drying. The characterization of synthesized solids with XRD revealed the presence of an X-ray amorphous phase of the samples and appearance of some humps. FTIR spectra of solids synthesized showed a band at 3700 cm-1 which is an isolated OH group, wide band at 3750-3000 cm-1 supported by the peak at 1650 cm-1 indicated the presence of absorbed water on the surface. Characteristic peaks for Mg-F and Mg-O vibrations were seen at 500-400 cm-1 and 600-500 cm-1 respectively. [ABSTRACT FROM AUTHOR]

A series of Zn-Doped Magnesium Hydroxyfluoride, Mg1-xZnxFOH) samples with Oto 0.15 of x were prepared using a sol-gel synthesis and dried with vacuum technique. XRD characterization of the samples indicated the amorphous phase of Mgl-xZnxFOH similarity with MgF2. The Zn doped in magnesium hydroxyfluoride did not affected on the basic structure of magnesium hydroxyfluoride. The FUR spectra showed the samples had a broad band at 3000-3700 cm-1 and 1620 cm-1 was indicated of adsorbed H20 molecules and a bridging hydroxyl groups, respectively. The intensity of the 460, and 550 cm-1 bands correlates to Mg-F and Mg-O vibrations. The Zn-O stretching vibration of Zn-doped magnesium hydroxyfluoride appeared at 1634 and 621 cm-1. [ABSTRACT FROM AUTHOR]

A series nickel doped magnesium hydroxyfluoride, Mg1-xNixFOH has been prepared by fluorolytic sol-gel method. The x values in these series were from 0 to 0,15. The samples structure was obtained as amorphous phase from XRD characterization. The XRD patterns showed any peaks like the mixing between magnesium fluoride (selllaite) and magnesium hydroxide (brucite). The IR spectra from FTIR characterization of Mg1-xNixFOH samples indicated the peaks of OH bridging at 3630-3000 cm-1, Ni-OH vibration around 660-650 cm-1 Mg-O vibration around 550 cm-1, and Mg-F vibration at 460 cm-1. [ABSTRACT FROM AUTHOR]

The novel synergistic flame retardant melamine phosphate-borate/magnesium hydroxide (MPB/MH) nanocomposites have been prepared by in-situ method and characterized by Fourier transform infrared (FTIR) spectroscopy, X-ray diffraction (XRD) and energy dispersive x-ray analysis (EDAX). Effects of reaction time and temperature on the MH crystalline size were investigated. The flame retardancy mechanisms of epoxide resin/MPB/MH (EP/MPB/MH) were proposed based on the elemental and structural analysis of the Fire residue, combining with the limited oxygen index (OI) and thermal analysis (TG) analysis. The successive dehydration and decomposition of boracic acid, melamine polyphosphate and MH result in both gas and condensed phases flame retardancy mechanisms. [ABSTRACT FROM AUTHOR]

Acid mine drainage, typically produced when pyrites in coal mining overburden is oxidised biologically and by atmospheric oxygen, contains high concentrations of dissolved heavy metals and sulphate, and can have pH values as low as 2.5. Unless treated, such waters can not be discharged into the environment. This study describes a method developed to neutralise acid mine drainage and to remove metals and sulphate. Magnesium hydroxide was used for neutralisation of acid mine drainage, by raising the pH to above pH 7 to enhance the oxidation of Fe(II) and precipitating it as Fe(OH)3 and other metals as hydroxides. Ba(OH)2 was used to precipitate sulphate as BaSO4 and magnesium as Mg(OH)2. CO2 treatment precipitated calcium as CaCO3. [ABSTRACT FROM AUTHOR]

Ground state structures and dehydrogenation characteristics of MgnH2n (n = 1-32) nanoclusters have been investigated using first principles DFT approach. Dehydrogenation temperature gets reduced compared to the bulk rutile phase of MgH2, indicating its favorable usage for hydrogen storage. [ABSTRACT FROM AUTHOR]