Effect of Different Parameters on Particle Diameters of Magnesium Salt Flame Retardants

2013 ◽  
Vol 750-752 ◽  
pp. 1267-1270 ◽  
Author(s):  
Xu Zhang ◽  
Dan Li ◽  
Hua Xie
Keyword(s):  
Particle Size ◽  
Aging Time ◽  
Flame Retardants ◽  
Ammonia Concentration ◽  
Magnesium Salt ◽  
Molar Ratio ◽  
Particle Size Analyzer ◽  
Optimization Parameters ◽  
Magnesium Salts ◽  
The Impact

The impact of the reaction temperature, ammonia concentration, aging time and molar ratio on the particle diameters of magnesium salt flame retardants have been systematically investigated through preparing magnesium salt powders under different conditions. Particle diameters are characterized by laser particle size analyzer, and the effect of different factors on the particle diameters is discussed, respectively. On the basis of the analysis, optimization parameters for synthesizing magnesium salts with the minimum particle diameters are found, which may be very helpful to the development of magnesium salt flame retardants

Fe3O4 Magnetic Preparation by Bauxite Ore Washing Fine Mud

2014 ◽  
Vol 1010-1012 ◽  
pp. 961-965
Author(s):  
Jian Qiang Xiao ◽  
Guo Wei He ◽  
Yan Jin Hu
Keyword(s):  
Particle Size ◽  
Aging Time ◽  
Average Particle Size ◽  
Xrd Analysis ◽  
Test Methods ◽  
Raw Material ◽  
Molar Ratio ◽  
Average Particle ◽  
Experimental Conditions ◽  
Particle Size Analyzer

Bauxite waste sludge as a raw material, the use of reverse chemical coprecipitation synthesize Fe3O4. Researching temperature, precipitation concentration, aging time and Fe2+/Fe3+ molar ratio effect on the particle size, morphology. Optimal experimental conditions: temperature 70 °C, the precipitant NaOH mass ratio of 10%, aging time 3h, Fe2+/Fe3+ molar ratio of 2:3. Test methods using a laser particle size analyzer, XRD analysis of the products were characterized, the product is Fe3O4, the average particle size of 0.11mm.

scholarly journals Nitrate-dominated PM<sub>2.5</sub> and elevation of particle pH observed in urban Beijing during the winter of 2017

2020 ◽  
Vol 20 (8) ◽  
pp. 5019-5033 ◽  
Author(s):  
Yuning Xie ◽  
Gehui Wang ◽  
Xinpei Wang ◽  
Jianmin Chen ◽  
Yubao Chen ◽  
...  
Keyword(s):  
Atmospheric Aerosols ◽  
Ammonia Concentration ◽  
Historical Record ◽  
Molar Ratio ◽  
Effective Control ◽  
Nitrate Content ◽  
Chinese Government ◽  
Low Level ◽  
The Impact ◽  
Pollution Episodes

Abstract. The Chinese government has exerted strict emission controls to mitigate air pollution since 2013, which has resulted in significant decreases in the concentrations of air pollutants such as SO2. Strict pollution control actions also reduced the average PM2.5 concentration to the low level of 39.7 µg m−3 in urban Beijing during the winter of 2017. To investigate the impact of such changes on the physiochemical properties of atmospheric aerosols in China, we conducted a comprehensive observation focusing on PM2.5 in Beijing during the winter of 2017. Compared with the historical record (2014–2017), SO2 decreased to the low level of 3.2 ppbv in the winter of 2017, but the NO2 level was still high (21.4 ppbv in the winter of 2017). Accordingly, the contribution of nitrate (23.0 µg m−3) to PM2.5 far exceeded that of sulfate (13.1 µg m−3) during the pollution episodes, resulting in a significant increase in the nitrate-to-sulfate molar ratio. The thermodynamic model (ISORROPIA II) calculation results showed that during the PM2.5 pollution episodes particle pH increased from 4.4 (moderate acidic) to 5.4 (more neutralized) when the molar ratio of nitrate to sulfate increased from 1 to 5, indicating that aerosols were more neutralized as the nitrate content elevated. Controlled variable tests showed that the pH elevation should be attributed to nitrate fraction increase other than crustal ion and ammonia concentration increases. Based on the results of sensitivity tests, future prediction for the particle acidity change was discussed. We found that nitrate-rich particles in Beijing at low and moderate humid conditions (RH: 20 %–50 %) can absorb twice the amount of water that sulfate-rich particles can, and the nitrate and ammonia with higher levels have synergetic effects, rapidly elevating particle pH to merely neutral (above 5.6). As moderate haze events might occur more frequently under abundant ammonia and nitrate-dominated PM2.5 conditions, the major chemical processes during haze events and the control target should be re-evaluated to obtain the most effective control strategy.

scholarly journals Formulation, Characterization and Antioxidant Myricetin Nanophytosome for Topical Delivery

2020 ◽  
Vol 8 (3) ◽  
pp. 9-13
Author(s):  
Purnamasari Nur Aini ◽  
Dzakwan Muhammad ◽  
Pramukantoro Ganet Eko ◽  
Mauludin Rachmat ◽  
El Fahmi
Keyword(s):  
Particle Size ◽  
Encapsulation Efficiency ◽  
Antioxidant Activities ◽  
Biological Effects ◽  
Radical Scavenging Activity ◽  
Radical Scavenging ◽  
Spherical Shape ◽  
Molar Ratio ◽  
Limiting Factor ◽  
Particle Size Analyzer

Background: Phytosomes are recently introduced drug delivery system and novel botanical formulation to produce lipophilic molecular complex to improve absorption and bioavailability of phytoconstituent. Myricetin is a well-known flavonoid with different biological effects and contributed in food preserving by free radical scavenging activity. However, bioavailability of myricetin is an important limiting factor for its antioxidant activities. Purpose: To overcome this limitation, in the present study we aimed to produce myricetin-loaded nano phytosomes to improve its physicochemical stability and bioavailability. Methods: myricetin-loaded nano phytosome was prepared by using phosphatidylcholine (PC) and cholesterol (CH). Myricetin nanophytosomes system was characterized by particle size analyzer, particle size distribution (PDI), encapsulation efficiency and potential antioxidant activity. Results: Results showed that formulation with the myricetin: PC: CH molar ratio of 1: 2: 0.8 had lower particle size (291.11 nm) and higher encapsulation efficiency percent (93%). Morphology analysis showed that myricetin nanophytosome spherical shape. The potential antioxidant data showed that incorporation myricetin in the phospholipid myricetin remained unchanged even after encapsulation of myricetin in binarynanophytosome formulation. Conclusion: Nano phytosomal formulation of myricetin showed promising potential in fortification of nutraceutical with water insoluble antioxidants.  

Synthesis and characterization of polyaniline nanomaterials with different molar ratio of monomer

2020 ◽  
Vol 3 (1) ◽  
Author(s):  
Priyanka S ◽  
Dhachanamoorth N ◽  
Birundha B
Keyword(s):  
Particle Size ◽  
Initial Conditions ◽  
Oxidative Polymerization ◽  
Molar Ratio ◽  
Synthesis Process ◽  
Chemical Oxidative Polymerization ◽  
Good Tool ◽  
Particle Size Analyzer ◽  
Ft Ir

Formation of polymer nanomaterials are achieved by the process of polymerization and there was an availability of different methods such as chemical oxidative polymerization,electro chemical polymerization, In-situ oxidative polymerization and emulsion polymerization etc., Many monomers combine to form polymers under certain conditions by chemical reactions between the monomers. The chemical oxidative polymerization was most commonly used method to synthesize PANI and the synthesis process involved various molar ratio of aniline (0.1M, 0.2M, 0.3M) in which APS was used as an oxidant with dopant of HCl. This study revealed that the properties changed based on their initial conditions. The prepared aromatic polyaniline was characterized by FT-IR, UV-VIS,Particle size analyzer techniques and anti-bacterial activity of the sample was analyzed.FT-IR spectroscopy gives deep view of many  functional groups that were present in a system by measuring vibrational frequencies of chemical bonds involved. UV-VIS was a good tool to identify, characterize and to study the optical properties of nanomaterials.In particle size analyzer, the size of a particle was measured using the instrument laser diffraction particle size analyzer (SALD-2300). The synthesized polyaniline had the tendency to resist the growth of both gram positive and gram negative bacteria. These organic conducting polymers were sometimes called “smart polymers” and have varies application in medical, OLED, solar cell, batteries and sensor etc.,

scholarly journals β-hexanitrohexaazaisowurtzitane Particles Prepared by Spray Drying and its Characterization

2021 ◽  
Vol 27 (1) ◽  
pp. 119-124
Author(s):  
Wenzheng XU ◽  
Hao LI ◽  
Xin LIANG ◽  
Jie WANG ◽  
Jinyu PENG ◽  
...  
Keyword(s):  
Particle Size ◽  
Spray Drying ◽  
Ultrafine Particles ◽  
Average Particle Size ◽  
Narrow Particle Size Distribution ◽  
Average Particle ◽  
Thermal Stimulus ◽  
Particle Size Analyzer ◽  
Xrd Patterns ◽  
The Impact

In this paper, the ultrafine β-hexanitrohexaazaisowurtzitane (β – CL – 20) particles were prepared by spray drying method. The CL – 20 samples were characterized by scanning electron microscope (SEM), particle size analyzer, X-ray diffraction (XRD), and Differential Scanning Calorimeter (DSC). Furthermore, the safety properties of samples under impact and thermal stimulus were tested and analyzed. The results of SEM showed that the average particle size of ultrafine CL – 20 particles with a narrow particle size distribution, were about 320 nm, and the shape was elliptical. The XRD patterns indicated that the polymorphic phase of ultrafine particles was mainly β-type. Compared with that of raw CL – 20, the impact sensitivity of the ultrafine CL – 20 had been decreased significantly, for the drop height (H50) was increased from 13.0 to 33.5 cm. The critical explosion temperature of the ultrafine CL – 20 decreased from 232.16 ℃ to 227.93 ℃, indicating that the thermal stability of the ultrafine CL – 20 is lower than that of raw CL – 20.

Effects of Synthesis Parameters on Hydrothermal Synthesis of NaA Zeolite

2010 ◽  
Vol 148-149 ◽  
pp. 1444-1448
Author(s):  
Lin Lin Yuwen ◽  
Meng Fu Zhu ◽  
Hong Bo Su ◽  
Xiu Dong You ◽  
Cheng Deng ◽  
...  
Keyword(s):  
Particle Size ◽  
Molar Ratio ◽  
Crystallization Time ◽  
X Ray Diffraction ◽  
Molar Ratios ◽  
Naa Zeolite ◽  
Optimum Synthesis ◽  
Synthesis Parameters ◽  
Particle Size Analyzer ◽  
Crystal Particle

In this research, NaA zeolite samples were synthesized from aluminosilicate solution through hydrothermal method. The effects of different parameters such as the SiO2/Al2O3, OH-/Si and H2O/Na2O molar ratios of the initial gel solution, crystallization time and temperature on the crystallinity and morphology of the synthesized zeolites were investigated. The final products were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM) and laser particle size analyzer. The experiment results indicated that the SiO2/Al2O3 molar ratio had influence on morphology and size of the synthesized zeolites, the optimum range of SiO2/Al2O3 molar ratio for synthesizing NaA zeolite was 1.5-2. Alkalinity (OH-/Si and H2O/Na2O molar ratio) had a significant effect on particle sizes of the synthesized zeolites, the higher the alkalinity, the smaller the crystal particle size. In addition, it was found that crystallization temperature during hydrothermal treatment played an important role in reducing the over all reaction time. The crystallization time had effect on the crystallinity of the synthesized zeolites. Finally, the optimum synthesis parameters can be proposed in order to synthesize NaA zeolite with desirable particle size, crystallinity and morphology.

Study on Thermal Decomposition Characteristics of Magnesium Salt Flame Retardants

2014 ◽  
Vol 915-916 ◽  
pp. 1058-1061 ◽  
Author(s):  
Xu Zhang ◽  
Dan Li ◽  
Hua Xie ◽  
Rui Feng Ma
Keyword(s):  
Thermal Analysis ◽  
Thermal Decomposition ◽  
Differential Thermal Analysis ◽  
Thermogravimetric Analysis ◽  
Flame Retardant ◽  
High Performance ◽  
Flame Retardants ◽  
Magnesium Salt ◽  
Combustible Gas ◽  
Optimization Parameters

Magnesium salt flame retardant is a new filler flame retardant agent, and can release the water and absorb the latent heat during the thermal decomposition, which can effectively inhibit the polymers decomposition and cool the combustible gas generated in the case of fire. In this paper, the magnesium salt flame retardant is synthesized in different conditions. Then the thermal decomposition features of the magnesium salt flame retardants with the smallest particle diameters are characterized by using thermogravimetric analysis and differential thermal analysis. Finally, on the basis of this analysis, optimization parameters for preparing the magnesium salt flame retardant with good thermal decomposition performance are obtained, which may be helpful for guiding the preparation of high-performance magnesium salt flame retardants and providing a beneficial reference.

scholarly journals Konduktivitas Apatit Lantanum Silikat La9.33Si6O26 Hasil Sintesis Hidrotermal dengan Mineraliser NaOH dan KOH

2018 ◽  
Vol 14 (1) ◽  
pp. 1
Author(s):  
Atiek Rostika Noviyanti ◽  
Dani Gustaman Syarif ◽  
Riansyah Amynurdin ◽  
Iwan Hastiawan ◽  
Iman Rahayu ◽  
...  
Keyword(s):  
Particle Size ◽  
Solid Oxide Fuel Cells ◽  
Solid Oxide ◽  
Molar Ratio ◽  
X Ray Diffraction ◽  
X Ray ◽  
Particle Size Analyzer ◽  
Lanthanum Silicates ◽  
Lanthanum Silicate ◽  
Apatite Type

<p>Apatit lantanum silikat banyak digunakan sebagai elektrolit pada sel bahan bakar padatan (SOFC). Beberapa oksida apatit lantanum silikat La<sub>9.33</sub>Si<sub>6</sub>O<sub>26 </sub>telah disintesis dengan metode hidrotermal guna mengamati pentingnya peranan mineraliser terhadap karakternya. Penelitian ini bertujuan untuk mengetahui pengaruh jenis dan konsentrasi mineraliser terhadap kristalinitas, ukuran partikel dan hubungannya dengan sifat konduktivitas oksida apatit lantanum silikat. Struktur, ukuran partikel dan konduktivitas oksida apatit masing-masing dikarakterisasi dengan XRD, PSA dan spektroskopi impedansi. Oksida apatit lantanum silikat diperoleh dengan melarutkan La<sub>2</sub>O<sub>3</sub> dan Na<sub>2</sub>SiO<sub>3</sub> dengan mol ratio 1,555 menggunakan mineraliser NaOH (3-5 M) dan KOH (0,3-0,7 M). Hasil penelitian menunjukkan bahwa kinerja elektrolit sangat ditentukan oleh kristalinitas dan morfologi apatit lanthanum silikat yang dipengaruhi oleh jenis dan konsentrasi mineralizer. Ukuran apatit lantanum silikat terkecil diperoleh dari hasil sintesis dengan menggunakan mineraliser NaOH 3 M yaitu 1,7889 µm, dengan nilai konduktivitas tertinggi yaitu 1,99×10<sup>-6 </sup>S/cm pada suhu operasi 600 ºC. Berdasarkan hasil tersebut NaOH 3 M merupakan mineraliser yang paling baik untuk menghasilkan apatit lanthanum silikat La<sub>9.33</sub>Si<sub>6</sub>O<sub>26</sub>.</p><p><strong>Conductivity of </strong><strong>L</strong><strong>anthanum </strong><strong>S</strong><strong>ilicate </strong><strong>A</strong><strong>patite </strong><strong>P</strong><strong>hase of La<sub>9.33</sub>Si<sub>6</sub>O<sub>26</sub> </strong><strong>P</strong><strong>repare</strong><strong>d</strong><strong> by </strong><strong>H</strong><strong>ydrothermal </strong><strong>S</strong><strong>ynthesis using NaOH and KOH as </strong><strong>M</strong><strong>ineralizer</strong><strong>. </strong>Lanthanum silicates are used as electrolytes in solid oxide fuel cells (SOFC). Some oxide-based apatite has been synthesized by hydrothermal method to observe mineralizer effect on the process of crystallization. The effect of type and amount of mineralizers for preparing apatite –type lanthanum silicate of La<sub>9.33</sub>Si<sub>6</sub>O<sub>26 </sub>was investigatedon its crystallinity, particle size, as well as on the conductivity properties relationship were investigated. The structure, particle size and conductivity of La<sub>9.33</sub>Si<sub>6</sub>O<sub>26</sub> was characterized using X-ray diffraction, particle size analyzer and impedance spectroscopy respectively. The results show that the electrolyte performance is strongly dependent on the crystallinity and the morphology textural of lanthanum silicate apatite affected by the type and amount of mineralizer. The lanthanum silicate apatiteprepared by La<sub>2</sub>O<sub>3</sub> and Na<sub>2</sub>SiO<sub>3</sub> (molar ratio of La<sub>2</sub>O<sub>3</sub> and Na<sub>2</sub>SiO<sub>3</sub> = 1.555), and NaOH (3; 4; 5 M) and KOH (0,3-0,7 M) as mineralizer. As a result, apatite-type lanthanum silicate was prepare using NaOH 3 M shows smallest particle (1.7889 μm) and highest conductivity (1.99 × 10-6 S / cm at 600 ºC). With respect to both particle size and conductivity, the NaOH 3 M can be selected as a suitable type and amount mineralizer for the preparation of excellent lanthanum silicate apatite La<sub>9.33</sub>Si<sub>6</sub>O<sub>26</sub>. </p>

SINTESIS DAN KARAKTERISASI NANOPARTIKEL KITOSAN – EKSTRAK KULIT BUAH MANGGIS (Garcinia Mangostana)

2013 ◽  
Vol 14 (3) ◽  
Author(s):  
Eriawan Rismana ◽  
Susi Kusumaningrum ◽  
Olivia Bunga P ◽  
Idah Rosidah ◽  
Marhamah Marhamah
Keyword(s):  
Particle Size ◽  
Sodium Tripolyphosphate ◽  
Chitosan Solution ◽  
The Other ◽  
Ionic Gelation ◽  
Garcinia Mangostana ◽  
Particle Size Analyzer ◽  
Cadmium Lead ◽  
Solvent Residue ◽  
Mold And Yeast

The chitosan – Garcinia Mangostana extract nanoparticles has been prepared by ionic gelation reaction by mixture 0.2 % chitosan solution in acetic acid with Garcinia Mangostana extract and it’s continued by reaction process with 0.1 % sodium tripolyphosphate. The particle size of material was determined by Particle Size Analyzer (PSA) that it showed in the range of 200 – 500 nm. The color, pH, water, α- mangostin, mercury, arsenic, cadmium, lead, totally microbe aerobic, totally mold and yeast, and solvent residue contents of nanoparticles were also examined by many methods that these resulted are yellow, 4.50 – 5.50, 89 – 90 %, 1.05 %, < 0.005 ppm, < 0.01 ppm, < 0.01 ppm, < 0.05 ppm, < 10 CFU/g, < 10 CFU/g and not detected, respectively. The other characterization was also observed that it’sincluded stability andTLC chromatogram. A mixture of nanoparticles with cosmetics bases was showed that it’s increased stability, homogeneity and easy to formed.

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