The Influence of Polymer Architecture on Nanosized Hydroxyapatite Precipitation

2008 ◽  
Vol 8 (2) ◽  
pp. 667-674 ◽  
Author(s):  
Özlem Dogan ◽  
Mualla Öner
Keyword(s):  
Thermal Stability ◽  
Particle Size ◽  
Atmospheric Conditions ◽  
Wet Chemical Synthesis ◽  
Air Atmosphere ◽  
Particle Size Analyzer ◽  
Sem Micrograph ◽  
Mean Size ◽  
Wet Chemical ◽  
The Mean

In this work we present a facile way to produce hydroxyapatite (HAP) nanoparticles by wet chemical synthesis in the presence of polyelectrolytes under controlled temperature, pH, and atmospheric conditions. The resulting calcium rich carbonated HAP is sintered in an air atmosphere to investigate the thermal stability of the synthesized powders. The morphology and microstructure of the HAP nanoparticles were investigated by XRD, SEM, FTIR spectroscopy, thermal analysis, and particle size analyzer. Polyelectrolytes affect the coherent length of the crystalline domain, the dimension and particle size distribution of the crystals. The reduction in size is greater in the direction of the c-axis. The SEM micrograph shows the formation of well-crystallized, agglomerated small particles of HAP. The mean size of the subunit is smaller than that of the surface of the grain observed in SEM. X-ray analysis have shown that the resulting particles have high thermal stability.

Batch Precipitation of Lead Iodide

1994 ◽  
Vol 59 (6) ◽  
pp. 1301-1304
Author(s):  
Jaroslav Nývlt ◽  
Stanislav Žáček
Keyword(s):  
Aqueous Solution ◽  
Particle Size ◽  
Particle Size Distribution ◽  
Size Distribution ◽  
Crystal Size ◽  
Lead Nitrate ◽  
Lead Iodide ◽  
Constant Rate ◽  
Mean Size ◽  
The Mean

Lead iodide was precipitated by a procedure in which an aqueous solution of potassium iodide at a concentration of 0.03, 0.10 or 0.20 mol l-1 was stirred while an aqueous solution of lead nitrate at one-half concentration was added at a constant rate. The mean size of the PbI2 crystals was determined by evaluating the particle size distribution, which was measured sedimentometrically. The dependence of the mean crystal size on the duration of the experiment exhibited a minimum for any of the concentrations applied. The reason for this is discussed.

Influence of Electrical Parameter on the Size of Superalloy Powders Prepared by Spark Plasma Discharge Process

2007 ◽  
Vol 561-565 ◽  
pp. 403-406
Author(s):  
Jun Yu ◽  
Chang Chun Ge ◽  
Guo Hua Ni ◽  
Lu Lu Meng ◽  
Wei Ping Shen ◽  
...  
Keyword(s):  
Particle Size ◽  
Pulse Duration ◽  
Electrical Parameter ◽  
Spherical Shape ◽  
Plasma Discharge ◽  
Discharge Process ◽  
Small Particle Size ◽  
Spark Plasma ◽  
Mean Size ◽  
The Mean

Superalloy powders, which have a small particle size and spherical shape, were prepared by a spark plasma discharge process. The electrical parameter, spark voltage, current and pulse duration have very important effects on the size distribution of produced superalloy powders. When current or pulse duration changed the mean size significantly changed.

Study on the Synthesis of Micron-Sized Magnesium Hydroxide Flame Retardant by Using a Gaseous Ammonia Bubbling Method

2013 ◽  
Vol 821-822 ◽  
pp. 1341-1345
Author(s):  
Bing Liang ◽  
Chang Jian Gao ◽  
Jiao Lv
Keyword(s):  
Particle Size ◽  
Reaction Time ◽  
Experimental Design ◽  
Particle Size Distribution ◽  
Flame Retardant ◽  
Magnesium Hydroxide ◽  
Design Procedure ◽  
Gaseous Ammonia ◽  
Particle Size Analyzer ◽  
The Mean

Micron-sized Mg (OH)2 particles were synthesized by precipitation of MgSO4 with gaseous ammonia. An experimental design procedure was used to investigate the effects of the concentration of MgSO4, temperature of the reaction, time of the reaction, assembly time, speed of stirring, ultraphonic, the introduce of NaOH and surfactant on the mean particle size and the particle size distribution. Laser particle size analyzer, XRD, TG-DTG, SEM and other instrument was used to characterize the product and corresponding particle size.

Particle Size Distribution of Cerate-Zirconate Powder Prepared via Three Different Methods

2015 ◽  
Vol 1108 ◽  
pp. 67-72 ◽  
Author(s):  
Najwa Adni Ibarahim ◽  
Nafisah Osman ◽  
Mohd Azlan Mohd Ishak
Keyword(s):  
Particle Size ◽  
Particle Size Distribution ◽  
Size Distribution ◽  
Supercritical Fluids ◽  
Particle Distribution ◽  
Sol Gel ◽  
Spherical Shape ◽  
Particle Size Analyzer ◽  
Powder Density ◽  
Sem Micrograph

Ceramics powder of BaCe0.54Zr0.36Y0.1O2.95 (BCZY) was synthesized using three different methods namely sol-gel (SG), supercritical fluid (SC) and sol-gel assisted supercritical fluids (SGSF).The respective prepared samples were denoted as S1, S2 and S3. The calcined powder (T= 1100 °C) was analyzed using particle size analyzer (PSA), Pcynometer and scanning electron microscope (SEM). PSA showed a single particle size distribution (PSD) for all samples except for S3 which exhibits bimodial particle distribution. PSD of the samples were in the range of 295-396 nm for the primary powder and 712-820 nm for secondary powder. High relative powder density for S1, S2, S3 were recorded at 95 %, 93 % and 99 %, respectively. Morphology of the calcined powders by SEM micrograph revealed that S1 is in spherical shape, S2 is in cubic structure and S3 showed a mixture of spherical and rod-like structure. It was found that SG and SC produce a single shape of powder with lower density compared with SGSF.

Influence of annealing temperature on optical, chemical and particle size properties of polyaniline nanomaterial

2020 ◽  
Vol 3 (1) ◽  
Author(s):  
Dhachanamoorthi N ◽  
Haripriya S
Keyword(s):  
Particle Size ◽  
Dominant Role ◽  
Oxidative Polymerization ◽  
Polymeric Materials ◽  
Electron Transition ◽  
Circuit Board ◽  
Heating Process ◽  
Particle Size Analyzer ◽  
Different Temperatures ◽  
Mean Size

Polyaniline is a representative conducting polymer because of its high electrical conductivity in doped state and it’s used in various fields of science and engineering because of its unique characteristics. Polymers are playing a dominant role in many areas such as material sciences, textile industries and chemical industries. Monomers of aniline are combined together to form a polymer of polyaniline by chemical oxidative polymerization method. The process of synthesis includes 1.5 M of aniline (C6H5N) as main reagent which causes chemical reaction, Sulfuric acid (H2SO4) as a dopant which alters its original electric and optical properties and Ammonium Peroxydisulfate (APS) as an oxidant which has the ability to oxidize and accept electrons. The synthesized nanoparticles are subjected to heating process at two different temperatures (200˚C and 400˚C). The prepared polymer material is characterized by UV-Visible Spectroscopy,Fourier Transform Infra-Red Spectroscopy, Particle Size Analyzer and antibacterial activity. The electron transition from ground state to excited state was revealed by UVVis Spectroscopy. Polymeric materials are identified using FTIR spectroscopy and it also exhibits the chemical bonds and structure of the sample. Particle Size Analyzer represents the mean size of the polyaniline sample. The overwhelming potential application of polyaniline includes manufacturing of circuit board, corrosion resistance, and fabrication of smart textiles.

Studying the Influence of Surfactants on Acrylate Emulsion

2015 ◽  
Vol 731 ◽  
pp. 506-509
Author(s):  
Yang Yu ◽  
Xiu Lan Xin ◽  
Yang Xiao ◽  
Xue Hua Cheng
Keyword(s):  
Thermal Stability ◽  
Surface Tension ◽  
Particle Size ◽  
Polymerization Process ◽  
Polymeric Surfactants ◽  
Particle Size Analyzer ◽  
Nonionic Emulsifier ◽  
Acrylate Emulsion ◽  
Covalently Linked ◽  
The Stability

Alkyl maleic reactive polymeric surfactants (AMRPS) was used to replace traditional anionic emulsifier. The cashew phenol polyoxyethylene ether (CPEO-9/15) was used to replace traditional nonionic emulsifier. The acrylate emulsion was synthesized by semi-continuous and pre-emulsification polymerization technology. The acrylate emulsion was analyzed by particle size analyzer, viscosity analyzer,surface tension,water absorption and thermal stability. The result showed that this surfactants could be reactive in the polymerization process and thus was covalently linked onto the surface of the latex particles of acrylate emulsion. So it was able to improve the stability of polyacrylate emulsion.

Wet-chemical synthesis of Li7P3S11 with tailored particle size for solid state electrolytes

2021 ◽  
pp. 132334
Author(s):  
Jianbin Zhou ◽  
Ying Chen ◽  
Zhaoxin Yu ◽  
Mark Bowden ◽  
Quin R. S. Miller ◽  
...  
Keyword(s):  
Particle Size ◽  
Solid State ◽  
Chemical Synthesis ◽  
Wet Chemical Synthesis ◽  
Wet Chemical ◽  
Solid State Electrolytes

scholarly journals The Influence of Starch Modification with Amylosucrase Treatment on Morphological Features

Processes ◽  
2020 ◽  
Vol 8 (11) ◽  
pp. 1409
Author(s):  
Hyeyoung Lee ◽  
Inmyoung Park
Keyword(s):  
Particle Size ◽  
Cross Section ◽  
Resistant Starch ◽  
Flat Surface ◽  
Particle Sizes ◽  
Particle Size Analyzer ◽  
The Mean ◽  
Waxy Corn ◽  
Slowly Digestible Starch ◽  
Scanning Electron

Amylosucrase (AS) is a starch-modifying enzyme from Neisseria polysaccharea used to produce low-glycemic starches such as slowly digestible starch (SDS) and resistant starch (RS). The morphology of native, control, and AS-modified waxy corn starches (230 and 460 U) was examined using a particle size analyzer and field-emission scanning electron microscopy (FE-SEM). AS modification of the starch elongated the glucose and resulted in higher SDS and RS contents. The mean particle sizes of the control, 230 U-AS-, and 460 U-AS-treated starches were 56.6 µm, 128.0 µm, and 176.5 μm, respectively. The surface of the 460 U-AS-treated starch was entirely porous and coral-like, while the 230 U-AS-treated starch had a partial dense and flat surface which did not react with AS. FE-SEM of the granule cross section confirmed that the center contained a dense and flat region without any evidence of AS reaction to either of the AS-treated starches. It was assumed that the particle size and porous and sponge-like particle features might be related to the SDS and RS fractions.

scholarly journals Comparison of hazes in freshly bottled and aged beers by multiple angle turbidimetry

2010 ◽  
Vol 28 (No. 1) ◽  
pp. 36-43
Author(s):  
P. Sladký ◽  
R. Koukol
Keyword(s):  
Particle Size ◽  
Particle Size Distribution ◽  
Size Distribution ◽  
Scattered Light ◽  
Distribution Measurement ◽  
Particle Size Distribution Measurement ◽  
Mean Size ◽  
The Mean ◽  
Dual Angle

The hazes of freshly bottled and aged pale lager beers determined with the 12° and 90° dual angle laboratory hazemeters and 10° to 90° range photogoniometer were compared and evaluated. The instruments were standardised in EBC formazin units. In freshly bottled beer, the forward (12°–25°) haze values were smaller approximately by a factor of three than the nephelometric (90°) values which yielded 0.33 EBC units. In aged beer, the forward haze was greater than the nephelometric one. Whereas the aged beer showed the greatest and the fresh beer the lowest intensity of scattered light, the formazin suspension intensity was in between. Due to the standardisation of the beer scattered intensities by relation to that of formazin, the standardised nephelometric haze in non-aged beer was greater than the forward haze, and vice versa in aged beer. The greater forward than the nephelometric haze in aged beer was caused by the growth of haze particles above the mean size of formazin particles which was larger than 2 μm as confirmed by the particle size distribution measurement.

Preparation of Anti-Mosquito Microcapsule Finishing Agent

2013 ◽  
Vol 821-822 ◽  
pp. 1353-1357 ◽  
Author(s):  
Jun Hua Wang ◽  
Gang Huang ◽  
Yong Tang Jia
Keyword(s):  
Particle Size ◽  
In Situ Polymerization ◽  
Melamine Formaldehyde ◽  
Optimum Synthesis ◽  
Particle Size Analyzer ◽  
The Mean ◽  
Oil Water ◽  
Finishing Agent ◽  
Water Ratio

Slow-released anti-mosquito microcapsules finishing agent was prepared using the resin of melamine-formaldehyde as wall and DEET as core by in-situ polymerization. The effects of emulsifier content and oil/water ratio on anti-mosquito finishing agent were investigated. Scanning electron microscopy (SEM) and laser particle size analyzer were employed to characterize the microcapsules. The optimum synthesis condition was: 3% emulsifier SMA and oil/water ratio at 4:17. Under the conditions, the mean particle size of the capsules was about 39μm.

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