Synthesis of aluminum hydroxide thin coating and its influence on the thermomechanical and fire-resistant properties of wood

Holzforschung ◽  
2014 ◽  
Vol 68 (7) ◽  
pp. 781-789 ◽  
Author(s):  
Nana Wang ◽  
Yanchun Fu ◽  
Yongzhuang Liu ◽  
Haipeng Yu ◽  
Yixing Liu
Keyword(s):  
Reaction Time ◽  
Aluminum Hydroxide ◽  
Viscoelastic Properties ◽  
Oxygen Index ◽  
Reaction Times ◽  
X Ray Diffraction ◽  
Wood Substrate ◽  
Relative Crystallinity ◽  
Limiting Oxygen Index ◽  
X Ray

Abstract Aluminum hydroxide [Al(OH)3] film on wood substrate has been synthesized by means of the hydrothermal (HT) method for improvement of wood’s mechanical properties and resistance to combustion. The HT temperature was set to 100°C and 120°C, and the reaction time varied from 4 h to 10 h. X-ray diffraction (XRD) and X-ray photoelectron spectrometry (XPS) results show that the thin film grown on wood surface was amorphous Al(OH)3 and the relative crystallinity of treated woods slightly improved. SEM observation revealed that the Al(OH)3 film is composed of regular micro/nano-sized spheres, whose production and size increase with the reaction time, and some AlO(OH) structures emerged at 120°C with reaction times longer than 6 h. The storage modulus of the wood treated at 100°C and 120°C for 8 h can be improved by 30%, while the viscoelastic properties are also influenced by the HT treatment and Al(OH)3 coating. The limiting oxygen index of raw wood rose from 24.7% to 27.9% after the treatment, which can be interpreted as a moderate improvement of the fire resistance.

scholarly journals Application of modified phytic acid as flame retardant in cellulosic paper

BioResources ◽  
2021 ◽  
Vol 16 (4) ◽  
pp. 7953-7965
Author(s):  
Qijie Chen ◽  
Zhi Rong ◽  
Zhuo Liu ◽  
Na You ◽  
Guangyang Xie
Keyword(s):  
Flame Retardant ◽  
Phytic Acid ◽  
Oxygen Index ◽  
Impregnation Method ◽  
X Ray Diffraction ◽  
Limiting Oxygen Index ◽  
X Ray ◽  
Char Length ◽  
Cellulosic Paper ◽  
Scanning Electron

A flame retardant containing phosphorus and nitrogen was synthesized using phytic acid and dicyandiamide, and it was subsequently used to prepare flame-retardant cellulosic paper via an impregnation method. Vertical flame and limiting oxygen index (LOI) were used to evaluate the flame retardancy of the paper. The paper containing modified phytic acid was characterized with Fourier transform infrared spectroscopy (FTIR), thermogravimetry (TG), X-ray diffraction (XRD), and scanning electron microscopy (SEM). When the concentration of modified phytic acid was 20%, the char length of the treated paper decreased from 12.5 cm to 4.1 cm, the LOI value increased from 19.6% to 41.5%, and the tensile index was only 3.66% lower than that of the control paper. The modified phytic acid was judged to have good flame-retardant effects on the paper.

ELECTROCHEMICAL SYNTHESIS AND CHARACTERIZATION OF DIFFERENT MORPHOLOGIES NANORAMSDELLITE-MnO2

NANO ◽  
2012 ◽  
Vol 07 (04) ◽  
pp. 1250030
Author(s):  
MADJID TORKAMAN ◽  
AZIZAN AZIZ ◽  
MOHAMAD ABU BAKAR ◽  
SULAIMAN AB GHANI
Keyword(s):  
Electron Microscopy ◽  
Reaction Time ◽  
Average Particle Size ◽  
Reaction Times ◽  
Average Particle ◽  
X Ray Diffraction ◽  
X Ray ◽  
Transmission Electron ◽  
Crystal Particle

In this work manganese dioxide (Ramsdellite- MnO2 ) was synthesized at room temperature using a facile electrochemical method. X-ray diffraction (XRD) was used to identify the type and the size of the crystal particle, while field emission scanning electron microscopy (FESEM) and energy filtered transmission electron microscopy (EFTEM) were used to show and identify the morphology of the particles and changes of their morphologies with the increase of reaction times. Fourier transform infrared (FTIR) spectroscopy confirmed the Mn–O bond. Results from XRD showed that optimum time for synthesis Ramsdellite- MnO2 was 9 h. The results of EFTEM showed a mixture of nanospheres and nanorods after 9 h reaction time while a homogenous morphology of nanospheres was detected at 12 h reaction time. Results confirmed on the existence of a correlation between the reaction time and the resulting nanostructures. Moreover, the EFTEM result showed that average particle size for 12 h was (25 ± 7 nm). The variation of calculated specific capacitance (F/g) versus the different scan rate has indicated that the efficiency of synthesized Ramsdellite- MnO2 nanostructures in 12 h reaction time was superior to 9 h.

scholarly journals Rapid four-component synthesis of dihydropyrano[2,3-c]pyrazoles using nano-eggshell/Ti(IV) as a highly compatible natural based catalyst

BMC Chemistry ◽  
2021 ◽  
Vol 15 (1) ◽  
Author(s):  
Arefeh Dehghani Tafti ◽  
Bi Bi Fatemeh Mirjalili ◽  
Abdolhamid Bamoniri ◽  
Naeimeh Salehi
Keyword(s):  
Thermo Gravimetric Analysis ◽  
Reaction Times ◽  
Diffraction Field ◽  
Gravimetric Analysis ◽  
X Ray Diffraction ◽  
X Ray ◽  
Solvent Free Conditions ◽  
High Yields ◽  
Work Up

AbstractNano-eggshell/Ti(IV) as a novel naturally based catalyst was prepared, characterized and applied for the synthesis of dihydropyrano[2,3-c]pyrazole derivatives. The characterization of nano-eggshell/Ti(IV) was performed using Fourier Transform Infrared spectroscopy, X-ray Diffraction, Field Emission Scanning Electron Microscopy, Energy-Dispersive X-ray Spectroscopy, and Thermo Gravimetric Analysis. Dihydropyrano[2,3-c]pyrazoles were synthesized in the presence of nano-eggshell/Ti(IV) via a four component reaction of aldehydes, ethyl acetoacetate, malononitrile and hydrazine hydrate at room temperature under solvent free conditions. The principal affairs of this procedure are mild condition, short reaction times, easy work-up, high yields, reusability of the catalyst and the absence of toxic organic solvents.

Facile Refluxing Synthesis of Hydroxyapatite Nanoparticles

2015 ◽  
Vol 68 (8) ◽  
pp. 1293 ◽  
Author(s):  
Pakvipar Chaopanich ◽  
Punnama Siriphannon
Keyword(s):  
Crystallite Size ◽  
Reaction Times ◽  
Single Step ◽  
Hydroxyapatite Nanoparticles ◽  
X Ray Diffraction ◽  
X Ray ◽  
Transmission Electron ◽  
Aqueous Mixture ◽  
Diffraction Patterns ◽  
Microscopy Images

Hydroxyapatite (HAp) nanoparticles were successfully synthesized from an aqueous mixture of Ca(NO3)2·4H2O and (NH4)2HPO4 by a facile single-step refluxing method using polystyrene sulfonate (PSS) as a template. The effects of reaction times, pH, and PSS concentration on the HAp formation were investigated. It was found that the crystalline HAp was obtained under all conditions after refluxing the precursors for 3 and 6 h. The longer refluxing time, the greater the crystallinity and the larger the crystallite size of the HAp nanoparticles. The HAp with poor crystallinity was obtained at pH 8.5; however, the well-crystallized HAp was obtained when reaction pH was increased to 9.5 and 10.5. In addition, the X-ray diffraction patterns revealed that the presence of PSS template caused the reduction of HAp crystallite size along the (002) plane from 52.6 nm of non-template HAp to 43.4 nm and 41.4 nm of HAp with 0.05 and 0.2 wt-% PSS template, respectively. Transmission electron microscopy images of the synthesized HAp revealed the rod-shaped crystals of all samples. The synthesized HAp nanoparticles were modified by l-aspartic acid (Asp) and l-arginine (Arg), having negative and positive charges, respectively. It was found that the zeta potential of HAp was significantly changed from +5.46 to –24.70 mV after modification with Asp, whereas it was +4.72 mV in the Arg-modified HAp. These results suggested that the negatively charged amino acid was preferentially adsorbed onto the synthesized HAp surface.

Facile hydrothermal synthesis of Fe3O4 nanoparticle and effect of crystallinity on performances for supercapacitor

2019 ◽  
Vol 12 (02) ◽  
pp. 1950019 ◽  
Author(s):  
Yue Xu ◽  
Ying Zhang ◽  
Xiaolan Song ◽  
Hanjun Liu
Keyword(s):  
Hydrothermal Method ◽  
Reaction Times ◽  
Amorphous Structure ◽  
Electrochemical Performances ◽  
X Ray Diffraction ◽  
Oxide Electrode ◽  
Facile Hydrothermal Method ◽  
X Ray ◽  
Pseudocapacitive Behavior ◽  
Adsorption Desorption

Fe3O4 nanoparticles were synthesized by a facile hydrothermal method using triethanolamine. Effects of reaction times (2–8[Formula: see text]h) on crystallinity and electrochemical performances of Fe3O4 were investigated. Samples were analyzed by X-ray diffraction, infrared spectroscopy, N2 adsorption–desorption, scanning electron microscope, galvanostatic charge/discharge, and cyclic voltammetry. Results showed that the crystallinity of Fe3O4 was increased with hydrothermal time, and the sample prepared at 2[Formula: see text]h displayed amorphous structure with small grain size and large surface area of 165.0[Formula: see text]m2[Formula: see text]g[Formula: see text]. The sample exhibited typical pseudocapacitive behavior with capacitance of 383.2[Formula: see text]F[Formula: see text]g[Formula: see text] at 0.5 Ag[Formula: see text] in Na2SO3 electrolyte. After 2000 cycles, the capacitance retention of Fe3O4 at 2[Formula: see text]h was recorded as 83.6%, much higher than 26.3% for sample at 8[Formula: see text]h. It indicated that hydrothermal method was an effective approach to obtain amorphous Fe3O4, implying the potential application for preparing metal oxide electrode for supercapacitors.

scholarly journals Electroless Deposition of Cu-SWCNT Composites

2019 ◽  
Vol 5 (4) ◽  
pp. 61 ◽  
Author(s):  
Raja ◽  
Esquenazi ◽  
Jones ◽  
Li ◽  
Brinson ◽  
...  
Keyword(s):  
Photoelectron Spectroscopy ◽  
Electroless Deposition ◽  
Reaction Times ◽  
Phase Identification ◽  
X Ray Diffraction ◽  
Copper Surfaces ◽  
X Ray ◽  
Dispersing Agent ◽  
Defect Sites ◽  
Walled Carbon Nanotubes

In this work, as-received HiPCO single walled carbon nanotubes (SWCNTs) are incorporated in a controllable manner at various concentrations into Cu-SWCNT composites via electroless plating, by varying the related reaction times, with polyethylene glycol (PEG) used as a dispersing agent. The resultant samples were analyzed using scanning electron microscopy (SEM) for morphology assessment, energy dispersive X-ray analysis (EDX) and X-ray photoelectron spectroscopy (XPS) for elemental analysis, X-ray diffraction (XRD) for the assessment of crystal phase identification, and Raman spectroscopy for the confirmation of the presence of the incorporated SWCNTs. The Cu-SWCNT composites were found to contain carbon, catalytic iron (associated with the raw, as-received SWCNTs), oxygen, and copper; the latter was found to be inversely proportional to carbon and iron contents. The oxygen (associated with both the SWCNT defect sites and oxidized copper surfaces) remained more or less constant regardless of the proportion of SWCNTs in the composites. The Raman IG:ID ratio remains within the experimental error constant, indicating that the electroless deposition does not have a deleterious effect on the SWCNTs. At short deposition times, SEM revealed a relatively dense structure comprising a distinctive fibrous morphology, suggestive of an underlying SWCNT substrate coated with copper; however, with increasing deposition, a more porous morphology is observed. The size of the granular particles increases up until 10 min of reaction, after which time it remains unchanged.

scholarly journals Synthesis of new bimetallic phosphate (Al/Ag3PO4) and study for its Catalytic performance in the synthesis of 1,2-dihydro-l-phenyl-3H-naphth [1,2-e]-[1,3] oxazin-3-one derivatives

2021 ◽  
Vol 11 (3) ◽  
pp. 215
Author(s):  
Achraf El Hallaoui ◽  
Tourya Ghailane ◽  
Soukaina Chehab ◽  
Youssef Merroun ◽  
Rachida Ghailane ◽  
...  
Keyword(s):  
Reaction Times ◽  
Catalytic Performance ◽  
X Ray Diffraction ◽  
One Pot ◽  
X Ray ◽  
Silver Sulfate ◽  
Triple Super Phosphate ◽  
Aryl Aldehyde ◽  
Ft Ir ◽  
First Time

<p>This work aims to prepare a new bimetallic phosphate catalyst using a new simple and effective method. This new catalyst was ready for the first time by a modification of Triple Super Phosphate (TSP) fertilizer with silver sulfate (AgSO<sub>4</sub>), followed by the impregnation of the aluminum atoms using aluminum nitrate (Al(NO<sub>3</sub>)<sub>3</sub>). The use of Al/Ag<sub>3</sub>PO<sub>4</sub>, for the first time as a heterogeneous catalyst in organic chemistry, offers a new, efficient, and green pathway for synthesizing 1,2-dihydro-l-phenyl-3H-naphth[1,2-e]-[1,3]oxazin-3-one derivatives by one-pot three-component cyclocondensation of b-naphthol, aryl aldehyde, and urea. The structure and the morphology of the prepared catalyst were characterized by spectroscopic methods such as X-Ray Diffraction (XRD), Fourier Transform Infrared spectroscopy (FT-IR), and dispersive X-ray spectrometry coupled with a scanning electron microscope (EDX-SEM). In addition, the optimization of the reaction parameters was carried out considering the effect of catalyst amount, the temperature, and the solvent. The procedure described herein allowed a comfortable preparation of oxazine derivatives with excellent yields, short reaction times, and in the absence of organic solvent.</p>

scholarly journals Optimization of Microwave Pre-Cooked Conditions for Gelatinization of Adzuki Bean

Foods ◽  
2022 ◽  
Vol 11 (2) ◽  
pp. 171
Author(s):  
Jianyou Zhang ◽  
Xuehua Xie ◽  
Lyu Zhang ◽  
Yiling Hong ◽  
Gaopeng Zhang ◽  
...  
Keyword(s):  
Starch Content ◽  
Polarized Light ◽  
Microwave Treatment ◽  
Adzuki Bean ◽  
X Ray Diffraction ◽  
Relative Crystallinity ◽  
Soaking Time ◽  
X Ray ◽  
Ft Ir ◽  
Microwave Time

Pre-cooked adzuki beans (Vigna angularis), which looks like dried adzuki bean, is easily cooked and preserved. This study aimed to optimize the microwave pre-cooked conditions on adzuki beans by applying the response surface methodology. The results showed that soaking time has a significant effect on the gelatinization degree of adzuki beans according to microwave time. The most suitable gelatinization and the sensory scores were obtained with a soaking time of 7.8 h, a microwave power of 830 W, and microwave time of 92 s. The pre-cooked treatment had no significant effect (p > 0.05) on the protein, free amino acid, fat and starch content of adzuki bean products. The results of SEM and polarized light microscopy showed that the surface and center of starch were damaged after microwave treatment. XRD showed that microwave pre-cooking did not change the crystal structure of starch and maintained the original order of type A structure while reducing the relative starch crystallinity. FT-IR showed that the pre-cooked treatment did not produce new structure in adzuki bean starch, but the ratio of 1047/1022 cm−1 was slightly decreased, indicating that the starch crystallization area decreased relative to the amorphous area and the relative crystallinity decreased. The results of FTIR were consistent with X-ray diffraction results. Therefore, microwaves improved the gelatinization of adzuki beans and made the pre-cooked adzuki beans more suitable.

The Influence of Introduction of Polyethylene Glycol on Synthesis of Bimodal Mesoporous γ-Al2O3

2013 ◽  
Vol 709 ◽  
pp. 89-92
Author(s):  
Xiang Li ◽  
Xin Mei Liu ◽  
Zi Feng Yan
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Polyethylene Glycol ◽  
Bet Surface Area ◽  
X Ray Diffraction ◽  
Relative Crystallinity ◽  
X Ray ◽  
Transmission Electron ◽  
Increasing Trend ◽  
Opposite Tendency

In the presence of polyethylene glycol (PEG2W),bimodal mesoporous γ-Al2O3 was successfully synthesized via hydrothermal method. The samples were respectively characterized by X-ray diffraction (XRD), N2 physisorption, transmission electron microscopy (TEM), thermogravimetric and differential scanning calorimeter (TG-DSC). Introduction of PEG2W can increase the relative crystallinity of AACH and γ-Al2O3. The BET surface area and pore volume of alumina shows an increasing trend with increasing of PEG2W content, while the pore size shows an opposite tendency. The PEG2W also plays an important role in inducing the formation of the nanorod-like alumina.

K5[FeO4] und K17[Fe5O16]: Zwei neue Kalium-Oxoferrate(III) / K5[FeO4] and K17[Fe5O16]: Two New Potassium Oxoferrates(III)

2005 ◽  
Vol 60 (12) ◽  
pp. 1224-1230 ◽  
Author(s):  
Gero Frisch ◽  
Caroline Röhr
Keyword(s):  
Linear Chain ◽  
Reaction Times ◽  
Structure Type ◽  
Maximum Temperature ◽  
X Ray Diffraction ◽  
Tetrahedral Geometry ◽  
Space Group ◽  
X Ray ◽  
Subsequent Quenching ◽  
Rich Mixtures

The title compounds were synthesized from potassium rich mixtures of Fe2O3, elemental potassium and the hyperoxide KO2 by applying short reaction times, a maximum temperature of 875 K and subsequent quenching of the samples. The structures of the two new oxoferrates(III) have been determined by single crystal X-ray diffraction. The orthoferrate(III) K5[FeO4] (Na5[GaO4] structure type, space group Pbca, a = 1124,0(2), b = 667,95(9), c = 2034,8(3) pm, Z = 4, R1 = 0,0585) exhibits isolated ortho-anions [FeO4]5− with nearly ideal tetrahedral geometry and Fe-O distance in the narrow range of 189 to 192 pm. The pentaferrate K17[Fe5O16] (space group Cm, a = 671,71(5), b=3560,8(3), c=670,81(5) pm, β =119,687(5)°, Z =2, R1=0,0291) crystallizes with a new structure type. Its building units are isolated novel penta-nuclear anions composed of five corner sharing [FeO4] tetrahedra. These linear chain pieces [Fe5O16] are arranged in a hexagonal rod packing, with a stacking sequence according to |:AB:| along the large monoclinic b axis. The structure is thus related to that of the tetra-ferrate K14[Fe4O13] with a comparable packing of tetra-nuclear ferrate(III) anions.

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