The nanomaterials have been widely used in various fields, such as photonics, catalysis, and adsorption, because of their unique physical and chemical properties. Therefore, their production methods are of utmost importance. Compared with traditional synthetic methods, the template method can effectively control the morphology, particle size, and structure during the preparation of nanomaterials, which is an effective method for their synthesis. The key for the template method is to choose different templates, which are divided into hard template and soft template according to their different structures. In this paper, the effects of different types of templates on the morphology of nanomaterials during their preparation are investigated from two aspects: hard template and soft template, combined with the mechanism of action.

Heat-treated wood, a relatively new product treated at high temperatures of 180 to 260°C, possesses new versatile and attractive properties, which make it popular for outdoor applications. It is of considerable importance to investigate the influence of sunlight on the weathering degradation processes. In order to understand the degradation processes, kiln-dried (untreated) and heat-treated (210˚C) jack pine woods (Pinus banksiana) were exposed to artificial sunlight irradiation for different periods. Before and after exposure, their color and wettability by water were determined. Structural changes and chemical modifications at exposed surfaces were also investigated using SEM, FTIR spectroscopy, and XPS. SEM studies show that degradation of middle lamellar, checking of cell wall and destruction of bordered pits were observed on heat-treated wood surface due to sunlight irradiation. FTIR spectroscopy and XPS studies on the behavior of function groups of lignin and the oxygen to carbon ratios have revealed that the photo-degradation of lignin and presence of extractives play important roles in discoloration and wetting behavior of heat-treated wood surfaces during irradiation. The structural changes also influence the wettabilty of samples.

Highlights• Study of coke pitch interaction by XPS, FTIR and sessile-drop techniques.• Interactions of three cokes and two pitches were studied.• Studied calcined coke and coke-pitch by FTIR-DRIFT, not reported in published article.• Atomic wt% and functional groups present on coke and pitch surfaces analyzed by XPS.• Wetting was correlated with the functional groups and evidence of reaction found. AbstractThe information on the interactions between coke and pitch is of great value for the aluminum industry. This information can help choose the suitable coke and pitch pairs as well as the appropriate mixing parameters to be used during the production of anodes. In this study, the interaction mechanisms of pitch and coke at the mixing stage were studied by a sessile-drop test using two coal-tar pitches as the liquid and three petroleum cokes as the substrate. The results showed that the coke-pitch interactions are related to both pitch and coke chemical compositions. The contact angle of different coke-pitch systems decreased with increasing time and temperature. At high temperatures, decreasing the pitch viscosity facilitated the spreading of pitch and its penetration into the coke bed. The chemical behavior of petroleum cokes and coal tar pitches were studied using the FT-IR spectroscopy and XPS. The results showed that the wettability behavior of cokes by pitches depends on their physical properties as well as the presence of surface functional groups of coke and pitch which can form chemical bonds.

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The X-ray photoelectron spectroscopy (XPS) study of three heat-treated North American wood species (jack pine, birch and aspen) was carried out to evaluate chemical modifications occurring on the wood surface during artificial weathering for different times. The results suggest that the weathering reduces lignin content (aromatic rings) at the surface of heat-treated wood, consequently, the carbohydrates content increases. This results in surfaces richer in cellulose and poorer in lignin. Heattreated wood surfaces become acidic due to weathering, and the acidity increases as the weathering time increases. Three possible reasons are given to account for the increase of acidity during weathering. The lignin content increases, whereas the hemicelluloses content decrease due to heat treatment. Heat-treated woods have lower acidity to basicity ratios than the corresponding untreated woods for all three species because of the decrease in carboxylic acid functions mainly present in hemicelluloses. The wood composition changes induced by weathering are more significant compared to those induced by heat treatment at wood surface. Exposure to higher temperatures causes more degradation of hemicelluloses, and this characteristic is maintained during weathering. However, the wood direction has more effect on chemical composition modification during weathering compared to that of heat treatment temperature. The heat-treated jack pine is affected most by weathering followed by heat-treated aspen and birch. This is related to differences in content and structure of lignin of softwood and hardwood. The use of XPS technique has proved to be a reliable method for wood surface studies.

Effect of artificial weathering on the wettability of three heat-treated North American species (jack pine, aspen, and birch) is studied from the point of view of the structural and chemical changes taking place on the wood surface. Weathering increases wettability of all three heat-treated woods by water. Changes in wettability during artificial weathering differ according to heat treatment procedure and wood species, and are likely due to combination of structural and chemical changes of the surfaces. SEM analysis indicates that cracks form due to degradation taking place during weathering. As a result, water has easier entry into the cell wall, which consequently increases wettability. IR spectra suggest that the OH/CH2 ratio for heat-treated specimens is inversely proportional to the contact angle regardless of the type of wood species. The presence of cellulose-rich layer on wood surface and increasing amount of amorphous cellulose transformed from crystallized cellulose due to weathering result in increase of hydroxyl, consequently, it increases heat-treated wood wettability.

Effect of artificial weathering on the surface structural changes of birch (Betule papyrifera) wood, heat-treated to different temperatures, was studied using the fluorescence microscopy and the scanning electron microscopy (SEM). Changes in the chemical structure of wood components were analyzed by FTIR in order to understand the mechanism of degradation taking place due to heat treatment and artificial weathering. The results are compared with those of the untreated (kiln-dried) birch. The SEM analysis results show that the effect of weathering on the cell wall of the untreated birch surface is more than that of heat-treated samples. The FTIR spectroscopy results indicate that lignin is the most sensitive component of heat-treated birch to the weathering degradation process. Elimination of the amorphous and highly crystallised cellulose is observed for both heattreated and untreated wood during weathering. It is also observed that heat treatment increases the lignin and crystallised cellulose contents, which to some extent protects heat-treated birch against degradation due to weathering.The weathering of untreated wood causes roughening and cracking of wood surface and damages its microstructure. Untreated wood exposed to outdoor weathering undergoes checking and surface erosion principally due to the effects of solar radiation and stresses imposed by cyclic wetting, temperature changes, environmental pollutants, and certain micro-organisms [1]. A number of researchers have examined the effect of weathering on the physical structure of wood [1][2][3][4][5][6][7][8]. Microscopic studies showed characteristic ridges on the S3 wall layer, wall checking, ray and pit degradation, and middle lamella breakdown. Several publications describe similar observations related to microscopic changes found on untreated wood surfaces which were artificially weathered by exposure to UV irradiation [9][10][11]. Changes observed on the wood surfaces due to artificial weathering were very similar to those caused by natural outdoor weathering [12]. The effect of weathering on the chemical structure of wood was also studied by means of FITR spectroscopy [13]. These studies generally have been carried out for untreated wood.High-temperature heat-treated wood is a relatively new product which is heated to high temperatures in the range of 180 and 260°C, depending on the species used and the desired material properties [14]. A few researchers have studied the micro-structural properties of heat-treated wood by means of SEM. Boonstra et al. [15,16] found that heat treatment had an effect on the anatomical structure of wood, and the extent of this effect depended on the wood species and the treatment method and conditions used. Softwood species with narrow annual rings which had an abrupt transition from earlywood to latewood were sensitive to tangential cracks in the latewood section. Radial cracks occurred mainly in impermeable wood species such as Norwegian spruce, caused by large stresses in the wood structure during treatment. Sapwo...

This paper comprehensively reviews the relevant literature and presents the methods and processes used to investigate the dimensional stabilization of wood using various modification techniques, including (a) hydrophobization of wood surfaces to block the entrance and exit of water; (b) impregnation treatment with bulking agents, such as resin and wax, to maintain wood in a swollen state and diminish dimensional changes caused by moisture; (c) chemical treatment with different chemical agents to reduce the hygroscopicity of the wood; and (d) high temperature heat treatment, which modifies wood components, reducing accessible hydroxyl groups and decreasing the possibility of water absorption. The results of dimensionally stabilizing wood via different treatments are interpreted and compared, and the effects of treating conditions and parameters on the dimensional changes of wood are analyzed.