scholarly journals Effect of Saturated Steam Heat Treatment on Physical and Chemical Properties of Bamboo

Molecules ◽  
2020 ◽  
Vol 25 (8) ◽  
pp. 1999 ◽  
Author(s):  
Qiuyi Wang ◽  
Xinwu Wu ◽  
Chenglong Yuan ◽  
Zhichao Lou ◽  
Yanjun Li
Keyword(s):  
Heat Treatment ◽  
Moisture Content ◽  
Treatment Time ◽  
Flexural Modulus ◽  
Initial Moisture Content ◽  
Chemical Properties ◽  
Saturated Steam ◽  
Xrd Patterns ◽  
Physical And Chemical ◽  
Steam Heat

The aim of this study was to investigate the effects of the heat treatment time and initial moisture content of bamboo on the corresponding chemical composition, crystallinity, and mechanical properties after saturated steam heat treatment at 180 °C. The mechanism of saturated steam heat treatment of bamboo was revealed on the micro-level, providing a theoretical basis for the regulation of bamboo properties and the optimization of heat treatment process parameters. XRD patterns of the treated bamboo slices were basically the same. With the increase in the initial moisture content of bamboo, the crystallinity of bamboo increased first and then decreased after treatment. Due to the saturated steam heat treatment, the content of cellulose and lignin in bamboo slices increased while the content of hemicellulose decreased, but the content of cellulose in bamboo with a 40% initial moisture content increased first and then decreased. The shear strength of treated bamboo changed little within 10 min after saturated steam heat treatment, and then decreased rapidly. During the first 20 min with saturated steam heat treatment, the compressive strength, flexural strength, and flexural modulus of elasticity of the treated bamboo increased, and then decreased.

Characteristics of Lithium Polysilicate Electrolyte Synthesized by Sol-Gel Processing

2007 ◽  
Vol 124-126 ◽  
pp. 1031-1034
Author(s):  
Bong Soo Jin ◽  
Bok Ki Min ◽  
Chil Hoon Doh
Keyword(s):  
Heat Treatment ◽  
Acid Treatment ◽  
Treatment Time ◽  
Sol Gel ◽  
Silicate Solution ◽  
Treatment Temperature ◽  
Lithium Silicate ◽  
Treatment Conditions ◽  
Xrd Patterns ◽  
Si Wafer

To find out suitable Si surface treatment and heat treatment conditions, acid treatment of Si wafer was done for lithium polysilicate electrolyte coating on Si wafer. In case of HCl treatment, the wet angle of a sample is 30o, which is the smallest wet angle of other acid in this experiment. Acid treatment time is 10 min, which is no more change of wet angle. Lithium polysilicate electrolyte was synthesized by hydrolysis and condensation of lithium silicate solution using perchloric acid. Thermal analysis of lithium polysilicate electrolyte shows the weight loss of ~23 % between 400 and 500 , which is due to the decomposition of LiClO4. The XRD patterns of the obtained lithium polysilicate electrolyte also show the decrement of LiClO4 peak at 400 . The optimum heat treatment temperature is below 400 , which is the suitable answer for lithium polysilicate electrolyte.

scholarly journals The prediction model of moisture content’s stabilization during tobacco strip drying process

2018 ◽  
Author(s):  
Mingjian Zhang ◽  
Feng Huang ◽  
Qing Chen ◽  
Le Wang ◽  
Haisheng Wang ◽  
...  
Keyword(s):  
Moisture Content ◽  
Probability Distributions ◽  
Chemical Properties ◽  
Mean Value ◽  
Drying Process ◽  
Variance Model ◽  
Initial Stage ◽  
The Mean ◽  
Agriculture Products ◽  
Physical And Chemical

A mathematical model was established to predict the mean value and variance of tobacco strip during drying processing, based that the physical and chemical properties of tobacco strip as agriculture products show probability distributions. The results show that the model can predict the mean value of moisture content at different times, and there is a certain deviation in predicting the variance of moisture content at initial stage of drying process. However, the prediction value of the variance of tobacco strip is much more accurate while the moisture content is between 8% and 10%, which is the interval of quality requirements.Keywords: tobacco strip; drying; mean value;variance model.  

scholarly journals Effect of Heat-Treatment on the Thermal and Mechanical Stability of Ni/Al2O3 Nanocrystalline Coatings

2020 ◽  
Vol 4 (1) ◽  
pp. 17
Author(s):  
Kavian O. Cooke ◽  
Tahir I. Khan ◽  
Muhammad Ali Shar
Keyword(s):  
Heat Treatment ◽  
Grain Size ◽  
Mechanical Stability ◽  
Chemical Properties ◽  
Treatment Temperature ◽  
Al2o3 Coating ◽  
Operational Temperature ◽  
Average Grain Size ◽  
Properties Of Materials ◽  
Physical And Chemical

Heat-treatment is a frequently used technique for modifying the physical and chemical properties of materials. In this study, the effect of heat-treatment on the mechanical properties, thermal stability and surface morphology of two types of electrodeposited coatings (pure-Ni and Ni/Al2O3) were investigated. The XRD analyses showed that the crystal structure of the as-deposited coating changes from slightly amorphous to crystalline as the heat-treatment temperature increases. The heat-treatment of both the pure-Ni and the Ni/Al2O3 coating caused an increase of the grain size within the coatings. However, the unreinforced Ni coating experienced a faster growth rate than the Ni/Al2O3 coating, which resulted in a larger average grain size. The temperature-driven changes to the microstructure of the coatings caused a reduction in the hardness and wear resistance of the coatings. The presence of nanoparticles within the Ni/Al2O3 coating can successfully extend the operational temperature range of the coating to 473 K by pinning grain boundaries.

Formation of NaNbO3 Crystals in Dielectric Glass and Glass-Ceramics of a Na2O-Nb2O5-Al2O3-SiO2 System

2008 ◽  
Vol 55-57 ◽  
pp. 229-232 ◽  
Author(s):  
S. Thongsaeng ◽  
Anuson Niyompan ◽  
Rungnapa Tipakontitikul ◽  
Kamonpan Pengpat
Keyword(s):  
Heat Treatment ◽  
Treatment Time ◽  
Glass Ceramics ◽  
Glass Production ◽  
Nucleating Agent ◽  
Aluminum Silicate ◽  
Phase Identification ◽  
Dielectric Glass ◽  
Xrd Patterns ◽  
Glass Compositions

Dielectric glass and glass-ceramics were derived from Na2O-Nb2O5-Al2O3-SiO2 system. Small amount of TiO2 were also introduced into glass compositions to study crystallization behavior of the glass with present of this nucleating agent. Conventional melt-quenching technique was employed for a glass production and the selected bulk glass samples were subjected to the heat-treatment process at appropriate temperature. After six different glass compositions were produced, and by observation with necked eyes, all obtained glass samples are in light brown color and some samples were opaque due to crystallization took place during quenching. Phase identification through XRD patterns show that there were 3 phases, NaNbO3, NaNbO8 and a sodium aluminum silicate compound, found in those opaque glass samples. NaNbO3 is a predominant phase in all samples. Fortunately, clear transparent glass was obtained from the composition with no TiO2 addition. Heat treatment of this glass did not induce phase change, three aforementioned phases still present. Increasing heat treatment time promoted a higher of observed intensity of NaNbO3. But the NaNbO3 crystalline size was not significantly developed with time. The dielectric response of the NaNbO3 crystals in the glass-ceramics samples are influenced by presence of other crystalline phases.

Effect of Heat Treatment on Decay Resistance of Chinese Fir and Pine

2012 ◽  
Vol 468-471 ◽  
pp. 1118-1122
Author(s):  
Yan Jun Li ◽  
Lan Xing Du ◽  
Gou Ying Hu ◽  
Xing Xia Ma
Keyword(s):  
Heat Treatment ◽  
Moisture Content ◽  
Treatment Time ◽  
Brown Rot ◽  
Decay Resistance ◽  
Chinese Fir ◽  
Heat Treatment Time ◽  
White Rot ◽  
Heat Treated ◽  
Brown Rot Fungus

To enhance decay resistance, the effect of heat treatment and the variation of chemical composition on Chinese Fir and Pine were investigated in this study — heat treatment temperature was 170°C, 190°C and 210°C, respectively, heat treatment time was 2, 3 and 4hours, respectively. Both of them were subsequently exposed to white-rot fungus and brown-rot fungus. The results showed that:(1) With the increasing of the heat treatment, decay resistance of Chinese Fir and Pine were improved, anti-corrosion of Pine after being heat treated at 190°C which were exposed to write-rot fungus can reach I, anti-corrosion of Chinese Fir after being heat treated at 170°C treated which were exposed to brown-rot fungus could reach I yet, After being heat treated at 210°C for 3 hours , the Chinese fir samples had no measurable weight loss when exposed to the write-rot fungus.(2) There was no remarkable influence on both Chinese Fir and Pine by heat treatment time.(3) The moisture content of Chinese Fir and Pine were lower than the moisture content that the rot fungus need, macromolecule chains such as cellulose and hemicellulose broke down, their contents decreased, and the hemicellulose decomposed into acetic acid, they prevented the growth of rot fungus.

scholarly journals PHYSICAL AND CHEMICAL PROPERTIES OF SORBENTS USED FOR WASTEWATER PURIFICATION FROM OIL PRODUCTS

2018 ◽  
Vol 61 (7) ◽  
pp. 136
Author(s):  
Grigoriy I. Gusev ◽  
Andrey A. Gushchin ◽  
Vladimir I. Grinevich ◽  
Tatyana V. Izvekova ◽  
Dmitriy V. Fillipov
Keyword(s):  
Moisture Content ◽  
Sorption Capacity ◽  
Chemical Properties ◽  
Oil Products ◽  
Physical And Chemical Properties ◽  
Adsorption Parameters ◽  
Wastewater Purification ◽  
Maximum Sorption Capacity ◽  
Physical And Chemical ◽  
And Chemical Properties

The work is devoted to the study of the physico-chemical and adsorption properties of synthetic and natural sorbents contaminated with oil products. The parameters such as sorption capacity for petroleum products, water adsorption and moisture content, bulk density, as well as parameters characterizing the sorption equilibrium in the surface layers (distribution coefficients, maximum adsorption values, Henry constants, Gibbs energy changes, adsorption coefficients and filling degrees) were determined. Adsorption isotherms for all sorbents are almost identical in character with a pronounced linear region in the region of low concentrations of oil products and correspond to isotherms of monomolecular adsorption. The sorption capacity of the sorbents under study varies from 10 to 50 mg of oil products per 1 g of sorbent. The maximum sorption capacity among the sorbents studied the Ol-Ex Hard possesses. This sorbent belongs to sorbents of the silicate group and Ol-Ex 82, based on polyurethane. The lowest moisture content is also characteristic for silicate sorbents and does not exceed 0.5 % of their mass. The maximum moisture adsorption is typical for sorbents of SONET Sorb and MGS Sorb. It was revealed that the surface of Ol-Ex Hard is almost completely filled with oil (q → 1), while for shungite the surface will be filled only by 13%. The most effective for trapping oil products should be considered the sorbent Ol-Ex Hard, for which the highest values of adsorption parameters are characteristic.Forcitation:Gusev G.I., Gushchin A.A., Filippov D.V., Grinevich V.I., Izvekova T.V. Physical and chemical properties of sorbents used for wastewater purification from oil products. Izv. Vyssh. Uchebn. Zaved. Khim. Khim. Tekhnol. 2018. V. 61. N 7. P. 136-142

scholarly journals The Influence of Saturated Steam on Moso Bamboo Quasi-static Micromechanical Properties: Nano-Scale Evaluation

2021 ◽  
Author(s):  
Tiancheng Yuan ◽  
Zhaoshun Wang ◽  
Xin Han ◽  
ZhuRun Yuan ◽  
XinZhou Wang ◽  
...  
Keyword(s):  
Heat Treatment ◽  
Cell Wall ◽  
Crystallinity Index ◽  
Thermal Modification ◽  
Moso Bamboo ◽  
Saturated Steam ◽  
Static Properties ◽  
Tan Δ ◽  
Increasing Temperature ◽  
Steam Heat

Abstract In this paper, in order to analyze the quasi-static properties of Moso bamboo, a new, environmentally friendly and eco-friendly method was used for bamboo thermal modification under the effect of saturated steam. Under saturated steam heat treatment, the chemical composition in bamboo decreased, and the bamboo cell wall shrunk slightly. The increased crystallinity index of cellulose and decreased intensity of peaks belong to hemicellulose were confirmed by XRD and Fourier transform infrared (FTIR) spectroscopy. In addition, the highest modulus of elastic and hardness of treated bamboo were 22.5GPa and 1.1GPa at 180℃/10 min. These conclusions confirmed the micro-mechanical properties of the bamboo cell wall were enhanced by saturated steam heat treatment. The E'r of differently treated bamboo increased with increasing temperature and time, while the E''r and tan δ negatively as a function of increasing frequency. Furthermore, this thermal modification can be regarded as a useful, environmental-friendly and eco-friendly treatment to outdoor use of bamboo-based materials.

scholarly journals Pine wood modification by heat treatment in air

BioResources ◽  
2008 ◽  
Vol 3 (1) ◽  
pp. 142-154
Author(s):  
Bruno M. Esteves ◽  
Idalina J. Domingos ◽  
Helena M. Pereira
Keyword(s):  
Heat Treatment ◽  
Moisture Content ◽  
Equilibrium Moisture Content ◽  
Dimensional Stability ◽  
Bending Strength ◽  
Hot Air ◽  
Low Dimensional ◽  
Tangential Directions ◽  
Steam Heat ◽  
Made In

Maritime pine (Pinus pinaster) wood has low dimensional stability and durability. Heat treatment was made in an oven using hot air during 2 to 24 h and at 170-200 ºC. A comparison was made against steam heat treatment. The equilibrium moisture content and the dimensional stability (ASE) in radial and tangential directions were evaluated at 35%, 65%, and 85% relative humidity. MOE, bending strength and wettability were also determined. At the same mass loss, improvements of equilibrium moisture content and dimensional stability were higher for oven heat treatment, but the same was true for mechanical strength degradation. A 50% decrease in hemicellulose content led to a similar decrease in bending strength.

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