scholarly journals Changes of major chemical components in larch wood through combined treatment of drying and heat treatment using superheated steam

2017 ◽  
Vol 63 (6) ◽  
pp. 635-643 ◽  
Author(s):  
Yonggun Park ◽  
Soo-Kyeong Jang ◽  
Jun-Ho Park ◽  
Sang-Yun Yang ◽  
Hyunwoo Chung ◽  
...  
Keyword(s):  
Heat Treatment ◽  
Superheated Steam ◽  
Combined Treatment ◽  
Chemical Components ◽  
Larch Wood ◽  
Major Chemical

Combined treatment of green pitch pine wood by heat and superheated steam and the effects on physical properties of the products

Holzforschung ◽  
2014 ◽  
Vol 68 (3) ◽  
pp. 327-335 ◽  
Author(s):  
Yonggun Park ◽  
Chang-Deuk Eom ◽  
Yeonjung Han ◽  
Jun-Ho Park ◽  
Yoon-Seong Chang ◽  
...  
Keyword(s):  
Heat Treatment ◽  
Physical Properties ◽  
Large Scale ◽  
Superheated Steam ◽  
Bending Strength ◽  
Combined Treatment ◽  
Decay Resistance ◽  
Green Wood ◽  
Heat Treated ◽  
Pitch Pine

Abstract Pitch pine (P. rigida) wood was treated with superheated steam (SHS) and the subsequent effects due to drying and heat treatment (HT) were observed. The following treatment parameters were tested: 180°C air HT, 220°C air HT, 0.1 MPa–180°C SHS HT, 0.1 MPa–220°C SHS HT, 0.5 MPa–180°C SHS HT, and 0.5 MPa–220°C SHS HT. No drying checks were observed in the specimens (500×150×50 mm3) treated at 0.5 MPa–220°C SHS and with these treatment parameters, equilibrium moisture content (EMC) was the lowest. Low EMC has an effect on physical properties such as shrinkage, compressive strength parallel to the grain, bending strength, hardness, and decay resistance. Based on the results, it is expected that the green wood in a large scale is possible to be simultaneously dried and heat-treated without occurrence of checks by the SHS HT process.

Isolation and HPLC Determination of the Chemical Components of Gentianella acuta (Michx.) Hulten

2018 ◽  
Vol 15 (1) ◽  
pp. 21-33
Author(s):  
Ying Wei ◽  
Yongqiao Liu ◽  
Yifan Hele ◽  
Weiwei Sun ◽  
Yang Wang ◽  
...  
Keyword(s):  
Medicinal Plant ◽  
High Speed ◽  
Chemical Constituents ◽  
Folk Medicine ◽  
Gradient Elution ◽  
Chemical Components ◽  
Isolation And Characterization ◽  
Major Chemical ◽  
Main Components ◽  
First Time

Background: Gentianella acuta (Michx.) Hulten is an important type of medicinal plant found in several Chinese provinces. It has been widely used in folk medicine to treat various illnesses. However, there is not enough detailed information about the chemical constituents of this plant or methods for their content determination. Objective: The focus of this work is the isolation and characterization of the major chemical constituents of Gentianella acuta, and developing an analytical method for their determination. Methods: The components of Gentianella acuta were isolated using (1) ethanol extraction and adsorption on macroporous resin. (2) and ethyl acetate extraction and high speed countercurrent chromatography. A HPLC-DAD method was developed using a C18 column and water-acetonitrile as the mobile phase. Based on compound polarities, both isocratic and gradient elution methods were developed. Results: A total of 29 compounds were isolated from this plant, of which 17 compounds were isolated from this genus for the first time. The main components in this plant were found to be xanthones. The HPLC-DAD method was developed and validated for their determination, and found to show good sensitivity and reliability. Conclusion: The results of this work add to the limited body of work available on this important medicinal plant. The findings will be useful for further investigation and development of Gentianella acuta for its valuable medicinal properties.

scholarly journals Dual Electrochemical Treatments to Improve Properties of Ti6Al4V Alloy

Materials ◽  
2020 ◽  
Vol 13 (11) ◽  
pp. 2479
Author(s):  
Stefano Rossi ◽  
Luciana Volgare ◽  
Carine Perrin-Pellegrino ◽  
Carine Chassigneux ◽  
Erick Dousset ◽  
...  
Keyword(s):  
Heat Treatment ◽  
Combined Treatment ◽  
Amorphous Film ◽  
Amorphous Layer ◽  
Good Alternative ◽  
Surface Treatments ◽  
Ex Situ ◽  
X Ray Diffraction ◽  
Transmission Electron ◽  
Fluid Environment

Surface treatments are considered as a good alternative to increase biocompatibility and the lifetime of Ti-based alloys used for implants in the human body. The present research reports the comparison of bare and modified Ti6Al4V substrates on hydrophilicity and corrosion resistance properties in body fluid environment at 37 °C. Several surface treatments were conducted separately to obtain either a porous oxide layer using nanostructuration (N) in ethylene glycol containing fluoride solution, or bulk oxide thin films through heat treatment at 450 °C for 3 h (HT), or electrochemical oxidation at 1 V for 3 h (EO), as well as combined treatments (N-HT and N-EO). In-situ X-ray diffraction and ex-situ transmission electron microscopy have shown that heat treatment gave first rise to the formation of a 30 nm thick amorphous layer which crystallized in rutile around 620 °C. Electrochemical oxidations gave rise to a 10 nm thick amorphous film on the top of the surface (EO) or below the amorphous nanotube layer (N-EO). Dual treated samples presented similar results with a more stable behavior for N-EO. Finally, for both corrosion and hydrophilicity points of view, the new combined treatment to get a total amorphous N-EO sample seems to be the best and even better than the partially crystallized N-HT sample.

scholarly journals Seasonal characteristics, formation mechanisms and source origins of PM<sub>2.5</sub> in two megacities in Sichuan Basin, China

2017 ◽  
Author(s):  
Huanbo Wang ◽  
Mi Tian ◽  
Yang Chen ◽  
Guangming Shi ◽  
Yuan Liu ◽  
...  
Keyword(s):  
Sichuan Basin ◽  
Urban Site ◽  
Chemical Components ◽  
Formation Mechanisms ◽  
Major Mechanism ◽  
Inorganic Aerosols ◽  
Seasonal Characteristics ◽  
Geographical Regions ◽  
Secondary Aerosols ◽  
Major Chemical

Abstract. To investigate the characteristics of PM2.5 and its major chemical components, formation mechanisms, and geographical origins in the two biggest cities, Chengdu (CD) and Chongqing (CQ) in Sichuan Basin, the most densely populated basin in China, daily PM2.5 samples were collected simultaneously at one urban site in each city from October 2014 to July 2015. Annual mean concentrations of PM2.5 were 67.0 ± 43.4 and 70.9 ± 41.4 μg m−3 at CD and CQ, respectively. Secondary inorganic aerosols (SNA) and organic matter (OM) accounted for 41.1 % and 26.1 %, respectively, of PM2.5 mass at CD, and 37.4 % and 29.6 % at CQ. Seasonal variations of PM2.5 and its major chemical components were significant, usually with the highest values in winter and the lowest in summer. SNA and OM were 1.7–3.4 times higher on polluted days than on clean days at both sites, whereas their percentage contributions to PM2.5 varied differently among the components and between the two sites. Gas-phase oxidation probably played an important role on the formation of secondary aerosols when PM2.5 mass varied in the range of 75–150 μg m−3, while heterogeneous transformation was likely the major mechanism on the heavy polluted days. Geographical regions causing high PM2.5 were identified to mainly distribute within the basin at both sites based on potential source contribution function (PSCF) analysis.

scholarly journals Barothermal Processing of Animal Feed Ingredients

2019 ◽  
Vol 29 (3) ◽  
pp. 428-442 ◽  
Author(s):  
Vladimir I. Syrovatka ◽  
Natalya V. Zhdanova ◽  
Aleksandr N. Rasskazov ◽  
Dmitriy I. Toropov
Keyword(s):  
Heat Treatment ◽  
Superheated Steam ◽  
High Pressures ◽  
High Efficiency ◽  
Animal Feed ◽  
Raw Materials ◽  
Digital Technologies ◽  
Feed Ingredients ◽  
System P ◽  
User Friendly

Introduction. The article substantiates the need for high-temperature processing of feed ingredients. Principles of operation and design features of the applied methods and equipment for feed production are considered. Phase transitions, along with advantages and energy, technological, and technical drawbacks are highlighted. The aim of the study is to justify a possibility of creating high-efficiency production lines using heat treatment of feeds by application of heat valves ensuring continuous loading of raw materials into a reactor and discharge of the treated feed at high pressures and temperatures. Materials and Methods. It is proposed to transfer the process of barothermal processing to a higher zone of the phase diagram of the system p,t (pressure and temperature). This is a section of the superheated steam zone with temperature 300–374 °C, pressure 12–21 MPa and treatment exposure 30–60 seconds, which replaces costly processes of normalizing, expansion, extrusion and granulation. The change in enthalpy in the pressure range 0–21 MPa and temperature range 0–600 °C is shown. Thermal modes are presented as formulas which is the basic condition for the use of digital technologies. Results. The design of the reactor with a thermal gate for loading and unloading, being the main unit of the production line of the feed heat treatment, was proposed. The results of the study are fundamental for the development of the sample flow low-capacity line. Discussion and Conclusion. The transfer of the process of barothermic processing of feed into the zone of superheated steam allows for the transfer of poorly digestible elements of grain and legumes in easily digestible, pathogen-free feed. Advantages of the reactor and line include the user-friendly design, energy saving and possibility of implementation of advanced digital technologies.

scholarly journals Effects of 2.45-GHz Electromagnetic Fields with a Wide Range of SARs on Micronucleus Formation in CHO-K1 Cells

2004 ◽  
Vol 4 ◽  
pp. 29-40 ◽  
Author(s):  
S. Koyama ◽  
Y. Isozumi ◽  
Y. Suzuki ◽  
M. Taki ◽  
J. Miyakoshi
Keyword(s):  
Heat Treatment ◽  
Electromagnetic Fields ◽  
Cell Damage ◽  
Combined Treatment ◽  
Chinese Hamster ◽  
Positive Control ◽  
Dependent Manner ◽  
Temperature Dependent ◽  
Chromosomal Breakage ◽  
Wide Range

There has been considerable discussion about the influence of high-frequency electromagnetic fields (HFEMF) on the human body. In particular, HFEMF used for mobile phones may be of great concern for human health. In order to investigate the properties of HFEMF, we have examined the effects of 2.45-GHz EMF on micronucleus (MN) formation in Chinese hamster ovary (CHO)-K1 cells. MN formation is induced by chromosomal breakage or inhibition of spindles during cell division and leads to cell damage. We also examined the influence of heat on MN formation, since HFEMF exposure causes a rise in temperature. CHO-K1 cells were exposed to HFEMF for 2 h at average specific absorption rates (SARs) of 5, 10, 20, 50, 100, and 200 W/kg, and the effects on these cells were compared with those in sham-exposed control cells. The cells were also treated with bleomycin alone as a positive control or with combined treatment of HFEMF exposure and bleomycin. Heat treatment was performed at temperatures of 37, 38, 39, 40, 41, and 42°C.The MN frequency in cells exposed to HFEMF at a SAR of lower than 50 W/kg did not differ from the sham-exposed controls, while those at SARs of 100 and 200 W/kg were significantly higher when compared with the sham-exposed controls. There was no apparent combined effect of HFEMF exposure and bleomycin treatment. On heat treatment at temperatures from 38–42°C, the MN frequency increased in a temperature-dependent manner. We also showed that an increase in SAR causes a rise in temperature and this may be connected to the increase in MN formation generated by exposure to HFEMF.

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