Preparation and Characterization of Superabsorbent Polymers Based on Sawdust

Sawdust, a cheap by-product of the timber and forestry industry, was considered as a framework structure to prepare superabsorbent polymer with acrylic acid (AA) and acrylamide (AM), the synthetic monomers. The effects of initiator content, crosslinker content, AA content, AM content, degree of neutralization of AA, and reaction temperature on the swelling rate of superabsorbent polymer were investigated. The synthesized polymer was characterized by Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), scanning electron microscopy (SEM), and thermogravimetric analysis (TGA). Under optimal synthesis conditions, the results showed that the swelling rate of the polymer in deionized water and 0.9% NaCl solution reached 738.12 and 90.18 g/g, respectively. The polymer exhibits excellent swelling ability, thermal stability, and reusability. After the polymer was introduced into the samples (soil or coal), the water evaporation rate of the samples was significantly reduced, and the saturated water holding capacity and pore structure were also significantly improved.

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Characterization of tin dioxide nanoparticles synthesized by oxidation

Cerâmica ◽

10.1590/0366-69132015613591919 ◽

2015 ◽

Vol 61 (359) ◽

pp. 328-333 ◽

Cited By ~ 9

Author(s):

R. C. Abruzzi ◽

B. A. Dedavid ◽

M. J. R. Pires

Keyword(s):

Gas Sensors ◽

Tin Dioxide ◽

X Ray Diffraction ◽

X Ray ◽

Synthesis Conditions ◽

Tetragonal Crystal ◽

Tetragonal Crystal Structure ◽

Activation Efficiency ◽

Complementary Techniques

AbstractTin dioxide (SnO2) is a promising material with great potential for applications such as gas sensors and catalysts. Nanostructures of this oxide exhibit greater activation efficiency given their larger effective surface. The present study presents results of the synthesis and characterization of tin dioxide under different conditions via oxidation of solid tin with nitric oxide. SnO2powder was characterized primarily by X-ray diffraction and scanning electron microscopy, as well as complementary techniques such as energy-dispersive X-ray spectroscopy, dynamic light scattering and Fourier transform infrared spectroscopy. The results indicated that the established synthesis conditions were suitable for obtaining rutile tin dioxide nanoparticles with a tetragonal crystal structure.

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Novel Synthesis Process and Characterization of Li-Mn-O Spinels for Rechargeable Lithium Batteries

MRS Proceedings ◽

10.1557/proc-496-257 ◽

1997 ◽

Vol 496 ◽

Cited By ~ 2

Author(s):

Toshimi Takada ◽

Hirotoshi Enoki ◽

Etsuo Akiba ◽

Takenori Ishizu ◽

Tatsuo Horiba

Keyword(s):

Strong Dependence ◽

Lattice Parameter ◽

Synthesis Process ◽

X Ray Diffraction ◽

Rechargeable Lithium Batteries ◽

Rietveld Refinements ◽

Synthesis Conditions ◽

New Process ◽

Homogeneous Composition

ABSTRACTA new process has been developed for the synthesis of well-crystallized Li-Mn-O spinels with a homogeneous composition Li[LixMn2-x]O4 (0.0≤x≤0.333) using the stoichiometry mixtures of lithium acetate and manganese nitrate as starting materials. The crystal structure of these compounds was studied with Rietveld refinements of the X-ray diffraction profiles. The lattice parameter of the spinels shows a strong dependence on the composition and manganese oxidation state. SEM micrographs indicate that the crystallites appear as single crystals. The size of the crystallites are in the range of 0.1 – 2μm, depending on the synthesis conditions. Samples with x≤0.125 show good electrode performance for the cell Li/Li1+xMn2-xO4 in the 4V region, whereas Li4Mn5O2 (x=0.333) spinels show good cyclability with a rechargeable capacity of over 100mAh/g in the 3V region.

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Superabsorbent Polymer With Excellent Water/Salt Absorbency And Water Retention, And Fast Swelling Properties For Preventing Soil Water Evaporation

10.21203/rs.3.rs-1119095/v1 ◽

2021 ◽

Author(s):

Haizhou Tian ◽

Sha Cheng ◽

Jianghong Zhen ◽

Ziqiang Lei

Keyword(s):

Water Retention ◽

Tap Water ◽

Good Effect ◽

Water Evaporation ◽

Swelling Kinetics ◽

Superabsorbent Polymer ◽

Application Development ◽

Swelling Properties ◽

Swelling Rate ◽

Water Salt

Abstract Superabsorbent polymers have important applications in many fields, but insufficiency of water/salt absorbency, water retention, and swelling rate limit its application development. Herein, we fabricated HEC-g-P (AA-co-AMPS)/laterite by aqueous solution polymerization, the structure and morphology of the superabsorbent polymer were characterized by FTIR, SEM and TG/DTG. The optimal water absorbency of the superabsorbent polymer were 1294 g/g, 177 g/g, and 119 g/g in distilled water, tap water, and 0.9 wt% NaCl solution, respectively. The superabsorbent polymer had good water retention and re-swelling properties at different temperatures, and fast water absorption rate, and reached swelling equilibrium at 5 min. The swelling mechanism of the superabsorbent polymer was explained by the pseudo-second-order swelling kinetics model and Ritger-Peppas model. The effect of the amount of hydrogel on the water evaporation rate in soil was studied, and it had a good effect.

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Preparation and characterization of high-dispersed pt/c nano-electrocatalysts for fuel cell applications.

Vietnam Journal of Science and Technology ◽

10.15625/0866-708x/54/4/7308 ◽

2016 ◽

Vol 54 (4) ◽

pp. 472

Author(s):

Hoang Anh Huy ◽

Tran Van Man ◽

Huynh Thien Tai ◽

Ho Thi Thanh Van

Keyword(s):

Fuel Cell ◽

Ethylene Glycol ◽

Pt Nanoparticles ◽

Carbon Support ◽

X Ray Diffraction ◽

Simple Method ◽

X Ray ◽

Synthesis Conditions ◽

Size Dispersion

Synthesis conditions are keys to controlling size and dispersion of Platinum (Pt) nanoparticle structures that is one of the most important goals in improving the electrochemical activity and durability of electrocatalyst as Pt nanoparticles catalyst for fuel cells. In this study, we introduce a simple method to address the effects of the temperature, pH and ethylene glycol enhancers (EG) on the morphology and size distribution of Pt nanoparticles catalyst in electrocatalyst fabrication process Pt nanoparticles on carbon support (Pt NPs/C). By using a facile method, we synthesized Pt NPs/C catalyst with and without using EG at room temperature and 60°C in pH = 6.5 and 11 solutions. The morphology, size, dispersion and activity of Pt nanoparticles catalyst on carbon support were characterized by using X-ray diffraction (XRD), Transmissionelectron microscopy (TEM) and Cyclic Voltammetry (CV). We found that the size, morphology and dispersion of Pt nanoparticles on carbon were strongly affected by adjusting the temperature, pH and the presence of ethylene glycol that could enhance catalytic activity of Platinum for fuel cell applications.

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Thermal synthesis and characterization of AlχLa1-χ P3O9

Open Chemistry ◽

10.2478/s11532-007-0020-1 ◽

2007 ◽

Vol 5 (3) ◽

pp. 706-714 ◽

Cited By ~ 1

Author(s):

Petr Bělina ◽

Petra Šulcová ◽

Miroslav Trojan ◽

Pavel Mazurek

Keyword(s):

Volume Concentration ◽

Specific Conductivity ◽

Synthesis And Characterization ◽

X Ray Diffraction ◽

Pigment Volume Concentration ◽

Thermal Synthesis ◽

X Ray ◽

Synthesis Conditions ◽

Dta And Tg

AbstractNew binary lanthanum-aluminum triphosphates were synthesized by thermal-condensation method from H3PO4, La2O3 and Al(OH)3. These pigments could be potentially used as special inorganic pigments; their corrosion-inhibition properties were widely studied. Synthesis conditions were determined on the basis of DTA and TG measurements. The products were also characterized by X-ray diffraction analysis. Physical properties — density by pycnometric method, particle size distribution, oil number and critical pigment volume concentration (CPVC), pH and specific conductivity of their aqueous extracts were also determined.

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Synthesis and structural characterization of Fe1-xMexBO3 (Me = Al, Sc) single crystals

Journal of Physics Conference Series ◽

10.1088/1742-6596/2103/1/012069 ◽

2021 ◽

Vol 2103 (1) ◽

pp. 012069

Author(s):

Yu Mogilenec ◽

K Seleznyova ◽

S Yagupov ◽

K Seleznev ◽

I Nauhatsky ◽

...

Keyword(s):

Single Crystals ◽

Fluorescence Analysis ◽

Flux Growth ◽

X Ray Diffraction ◽

Growth Technique ◽

X Ray ◽

Synthesis Conditions ◽

Initial Charge ◽

Crystal Lattice Parameters

Abstract Fe1-xMexBO3 (Me = Al, Sc) single crystals have been synthesized by flux growth technique using B2O3-PbO-PbF2 solvent and approach of identical synthesis conditions. The contents of the diamagnetic ions Me in the initial charge of both compositions were equal, xcharge=0.05. The exact contents and crystal lattice parameters of the synthesized crystals were determined by X-ray fluorescence analysis and X-ray diffraction, respectively.

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Synthesis of alloyed Bi2TexSe(3-x) nanoparticles and thermoelectric characterization of bulk nanostructured materials obtained by their assembly

MRS Proceedings ◽

10.1557/opl.2015.485 ◽

2015 ◽

Vol 1804 ◽

pp. 1-6 ◽

Cited By ~ 1

Author(s):

Romain Bude ◽

Laurent Divay ◽

Renato Bisaro ◽

Bernard Servet ◽

Elodie Leveugle ◽

...

Keyword(s):

Careful Study ◽

Selenium Content ◽

X Ray Diffraction ◽

Synthesis Conditions ◽

Simultaneous Control ◽

Solution Route ◽

Diffraction Peaks ◽

The Difference ◽

Low Selenium

ABSTRACTThe optimization of the figure of merit of thermoelectric materials requires the simultaneous control of the material composition and microstructure. Assembly of nanoparticles obtained by a solution route is an attractive bulk fabrication method because size and shape of the nanoparticles can be tuned by variation of the synthesis conditions. Recently, new synthetic pathways were reported among which reducing agent assisted, surfactant free processes. We report here the evaluation of this method for the synthesis of Bi2TexSe3-x alloyed nanoparticles with varying selenium concentrations. X-ray diffraction studies conducted on powder and pellet samples show that two alloyed phases are present in the sample even at low selenium content. The careful study of the position of the diffraction peaks as function of the formulation shows that this behaviour could arise from the difference in reactivity of selenium and tellurium. Moreover, the electrical conductivity of the samples is shown to increase upon selenium addition while the Seebeck coefficient is reduced. Power factor shows an optimum value around 20% selenium content with a large tolerance in composition.

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Characterization of Leca Clay Pebbles as a Growing Medium for Geranium (Pelargonium hortorum) Stock Plant Production

HortScience ◽

10.21273/hortsci.30.4.902f ◽

1995 ◽

Vol 30 (4) ◽

pp. 902F-902

Author(s):

Mana Libran ◽

David J. Williams

Keyword(s):

Production Systems ◽

Exchange Capacity ◽

Plant Production ◽

Stock Plant ◽

X Ray Diffraction ◽

X Ray ◽

Growing Medium ◽

Water Holding ◽

Plate Apparatus

Leca clay pebbles were characterized and tested as a possible growing-medium for use in floriculture production systems that recycle irrigation water. Leca clay pebbles are light porous particles made by heating clay. X-ray diffraction tests indicate that high manufacturing temperatures (1100C) result in final particles composed primarily of quartz. Water-holding capacity was determined by pressure plate apparatus at eight pressures. Leca particles that were 4 to 8 mm retained more water than particles sized 12 to 18 mm. The bulk density of the particles were 0.43 and 0.37 g/cc for the 48-mm and the 12- to 18-mm particles, respectively. The pH of the leca particles was 7.77. The cation exchange capacity of the leca particles was relatively low compared to a standard soilless growing medium of 1 pine bark: 1 peat: 1 perlite (by volume). Leca particles have a CEC of o.82 me/100 g Ca and 6.36 me/100 g K, where the CEC of the previously mentioned soilless.medium was 24.21 me/100g Ca and 30.08 me/100 g K. Leca clay pebbles were tested as growing medium for the production of geraniums (Pelargonium hortorum) stock plants.

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Synthesis and Characterization of Nanocrystalline YSZ Powder by Smoldering Combustion Synthesis

Journal of Nanomaterials ◽

10.1155/jnm/2006/49283 ◽

2006 ◽

Vol 2006 ◽

pp. 1-7 ◽

Cited By ~ 23

Author(s):

Ingeborg Kaus ◽

Paul Inge Dahl ◽

Johann Mastin ◽

Tor Grande ◽

Mari-Ann Einarsrud

Keyword(s):

Crystallite Size ◽

Combustion Synthesis ◽

Surface Area ◽

X Ray Diffraction ◽

Synthesis Conditions ◽

Calcination Temperatures ◽

Smoldering Combustion ◽

Transmission Electron ◽

Carbonate Species

Nanocrystalline yttria-stabilized zirconia (YSZ) powders with 8 mol% Y2O3have been produced using smoldering combustion synthesis with glycine as fuel and nitrate as oxidizer. The YSZ powders prepared by using different glycine to nitrate ratios (0.20–1.0) have been characterized by X-ray diffraction (crystallite size), thermogravimetry, infrared spectroscopy, surface area analysis, transmission electron microscopy, and dilatometry to determine the parameters giving the powder the best properties when it comes to densification properties. The influence of calcination temperature on crystallite size, surface area, and carbonate species remaining from the smoldering combustion reaction has been studied especially for the G/N ratio of 0.23 to reveal the optimal synthesis conditions. A G/N ratio of 0.23 and calcination in the range 650–900ºC in oxygen flow gave high quality powder with a crystallite size less than 10 nm. Densities of sintered bodies exhibit an increase for calcination temperatures above 600ºC, where most of the residual carbonate species has been removed.

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Synthesis, Structures, and Physical Properties of Yttrium-Doped Strontium Manganese Oxide Films

MRS Proceedings ◽

10.1557/proc-718-d9.4 ◽

2002 ◽

Vol 718 ◽

Cited By ~ 3

Author(s):

Andrew J. Francis ◽

Paul A. Salvador

Keyword(s):

Thin Films ◽

Manganese Oxide ◽

Alkaline Earth ◽

Epitaxial Thin Films ◽

X Ray Diffraction ◽

Metal Insulator ◽

X Ray ◽

Synthesis Conditions ◽

Colossal Magnetoresistive

AbstractCubic strontium manganese oxide is an end-member of the colossal magnetoresistive (CMR) family of manganese-based perovskites, Ln1-xAExMnO3. Because normal synthesis conditions lead to the 4-H hexagonal polymorph, high-pressure conditions are typically used to obtain the cubic perovskite polymorph. In this work, we describe the synthesis and structural/physical characterization of the cubic perovskite form of the high-alkaline-earth containing phases of Y1-xSrxMnO3 (x ≥ 0.7) as epitaxial thin films. Thin films of various stoichiometries were grown on single-crystal perovskite substrates SrTiO3, NdGaO3, and LaAlO3 using pulsed laser deposition. After optimizing deposition conditions, the perovskite polymorph is obtained using PLD at 800°C and 10-100 mTorr O2 for x=1, 0.9, 0.8, and 0.7, as demonstrated by x-ray diffraction. Epitaxial growth was determined to be cube-on-cube. Electrical property measurements demonstrated insulating behavior and no metal-insulator transition or magnetoresistive behavior, similar to related stable compounds.

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