Research Articles

A comprehensive investigation was undertaken of red–black lacquer films excavated from a tomb in the Qin and Han Dynasty period (221 BC to AD 8). Cross-sectional observation was conducted via metallomicroscopy and field-emission scanning electron microscopy (FE-SEM). Morphological characteristics were investigated via FE-SEM with energy dispersive X-ray spectrometry (EDX). X-ray diffraction (XRD) and Fourier transform infrared (FTIR) spectroscopy were also conducted. The results of the cross-sectional analysis showed that the finished lacquer films on the wood body included a ground layer with coarse materials and a lacquer layer with delicate materials. Both SEM and EDX indicated that carbon black was used as the main black pigment, and cinnabar was used as the main red pigment. Compared with the standard card test, the XRD patterns of the Chinese lacquer were similar to that of quartz (SiO2), indicating that SiO2 was used as a putty powder during lacquer finishing. Compared with the FTIR spectrum of the fresh lacquer film, only a small amount of free carbonyl was found in the degraded lacquer, and some organosilicates were likely generated during degradation spanning thousands of years.

A new algal-bacterial granular sludge treatment method was used to treat salty eutrophication water. The results indicated that the treatment removed more than 98% of the total inorganic nitrogen and the total phosphorus after a 15 d cultivation period using 2% salinity simulated eutrophication water. For the 4% salinity simulated water, the total phosphorus was not able to be removed and was even higher in the effluent; and the total inorganic nitrogen was only removed 17%. Thus, the algal-bacterial granules were efficient for removing nitrogen and phosphorus in 2% salinity eutrophication water but were not effective for 4% salinity water. High levels of filamentous algae proliferation growing on the surface of the granules was primarily responsible for the good performance in 2% salinity water. However, the lipid accumulation was greatly enhanced (reactor R2 at a 27.6% increase and reactor R4 at a 107% increase) for both granule types due to the algal growth. Thus, treatment of the salty eutrophication water can also greatly increase the added-value of the algal-bacterial granules.

Heat treatment of wood materials is generally performed to improve the physical, mechanical, chemical, surface, thermal, and crystallinity characteristics. In this way, the usage areas of wood material in different purposes can be expanded by means of heat treatment. The goal of this study was to determine the physical, mechanical, chemical, crystallinity, and surface properties of heat-treated Scots pine (Pinus sylvestris L.) wood. The test samples were heat-treated at 120 °C, 150 °C, 180 °C, and 210 °C for 4 and 6 h in a laboratory-scale oven. The shrinking and swelling chracteristics of wood was decreased as a function of heat treatment processes. Bending strength, compression strength, and modulus of elasticity decreased. In addition, lignin ratios and crystallinity index increased as temperature and duration of the treatment were increased. Consequently, heat-treated wood materials can be used in various areas by developing some of their properties.

The cellulolytic bacterial flora present in the rumen of Inner Mongolian sheep are thought to have a high degree of cellulose-degrading activity because of their foraging feeding regimen. However, there are no report on the genetic and species composition of the cellulolytic bacterial flora. In this study, cellulolytic bacteria were isolated from the rumen of Inner Mongolian sheep using a combined method of transparent zone and filter paper degradation. Twenty-two strains were identified via morphological, physiological, and biochemical tests. Ten strains were further identified via DNA (G + C) mol%, together with 16S rDNA gene sequencing analysis. Four types of extracellular and total cellulase activities of representative strains were determined. The results demonstrated that the isolates included Butyrivibrio fibrisolvens, Rumincoccus albus, R. flavefaciens, Fibrobacter succinogenes, and Clostridium polysaccharolyticum. A big proportion of cellulolytic Butyrivibrio fibrisolvens was found in the rumen of Inner Mongolian sheep. This was the first study to analyze the cellulolytic bacterial flora in the rumen of foraging Inner Mongolian sheep. These results indicated that the rumen of Inner Mongolian sheep represents an attractive source for cellulolytic microorganisms and enzymes, and the research results have a certain guiding importance for the efficient degradation of cellulosic materials.

Powder coating is environmentally friendly and safe in terms of human health and is used especially on home appliances and in the automotive sector. Because of these advantages, recent studies have expanded work on the application of powder coating on non-conductive surfaces. Within the scope of this research, low temperature curing (120 °C to 130 °C) was applied on wood-based composite panels of medium-density fiberboard (MDF), particleboard, and plywood to facilitate conductivity. Epoxy, polyester, and hybrid (epoxy-polyester) types of powder paint and water-based liquid paint (control group) were applied to the surface of materials. Panels coated with the powder coatings were compared to the panels coated with the water-soluble acrylic resin coating. The prepared samples were analyzed for performance properties. The best results for thickness swelling, water absorption, adhesive strength, abrasion, and scratch resistance were found for the plywood coated with water-based liquid paint, MDF coated with polyester-based powder paint, plywood coated with hybrid powder paint, particleboard coated with hybrid powder paint, and plywood coated with epoxy powder paint, respectively.

Groundwood pulping is a process in which logs are pressed against a rotating grinding stone. A conventional grinding stone is generally made of grinding particles in a vitrified matrix. As the particles are practically round, their contact with the wood is limited to occasional point contacts. The interaction between the particles and the wood occurs at random positions and at random times, only intermittently contributing to the defibration process. In this work, well-defined grinding tools with asperities giving line contacts rather than point contacts were tested. The tool surface asperities were elongated in shape and positioned with different density over the surface. The tools were tested in a lab-scale equipment at elevated temperatures, and their performance was compared to that of a conventional grinding stone. The grinding mechanisms varied between the different tools, and the specific grinding energy was reduced compared to the conventional tool.

Studies regarding the determination of the ecological characteristics of the natural distribution areas of the silver linden (Tilia tomentosa Moench) are limited. It is of great importance to select areas with similar natural cultivation characteristics in the plantations established for flower or timber production. Physiographical factors affecting these forests were explored to determine the physical and chemical characteristics of the soil. The soil samples were collected from three natural populations, and a total of 43 samples were examined in terms of aspect, elevation, declivity position, and slope. It was determined that the natural linden populations expanded between the altitudes of 0 m and 400 m and 88% of the populations were denser in aspects with shadow. It was found that 91% of the soil was in the class of “deep to very deep”, 61% showed an expansion in sandy clay loam soils, and 30% showed an expansion in sandy loam soils. Average soil pH ranged between 5.6 and 6.6. The soils were found to be salt-free and slightly limy. In terms of the organic carbon amount, the soils were classified as medium.

The pretreatment of Mongolian pine (Pinus sylvestris var. mongholica Litv.) was conducted with saturated wet air (80 °C) and atmospheric saturated steam (100 °C) before high-frequency vacuum drying. Effects of the pretreatment on moisture content (MC), drying rate, drying crack, and drying shrinkage strain were investigated. The results showed that through pretreatment, the initial MC of the test material decreased by 2.6% to 6%, and the MC distribution was uniform. The maximum difference of the untreated wood MC distribution after drying was 2%, while that within the pretreated wood was less than 1%. The drying rate also increased, as the drying rates of the untreated and pretreated wood were 0.268%/h, 0.333%/h, and 0.398%/h, respectively. The drying shrinkage strain of the sample was reduced. The drying shrinkage strain of untreated wood was between 0.044 and 0.063, while the drying shrinkage strain of pretreatment wood was between 0.013 and 0.049. The crack of the test material was also reduced, and the drying quality was improved. The pretreatment reduced the high-frequency vacuum drying stress of wood and improved the drying speed and quality.

This study aimed to determine the gloss and hardness values of low-density wood materials densified using the Thermo-Vibro-Mechanic® (TVM) method after pretreatment with wood stain and wood preservative. This was carried out with a TVM density press that was designed and produced with the support of project 115O138 of the Scientific and Technological Research Council of Turkey (TUBITAK). The samples obtained from Uludağ fir (Abies bornmüelleriana Mattf.) and black poplar (Populus nigra L.) were pretreated with wood stain and wood preservative prior to the TVM densification process. The TVM densification operation was conducted at three different temperatures, three different vibration pressures, and three different vibration times. After the TVM densification process, changes in the gloss (ISO 2813 2014) and Brinell hardness values (TS 2479 1976) of the samples were determined. According to the results, the TVM densification method increased the gloss value of the Uludağ fir and black poplar wood pretreated with the wood preservative by 175% and 1390%, respectively, and increased the Brinell hardness value by 63% and 150%, respectively.

In this study, 1,3-dimethylol-4,5-dihydroxyethyleneurea (DMDHEU) and furfuryl alcohol (FA) modification catalyzed by acrylic acid were comparatively studied. The effects on physical-mechanical properties and durability against mould of Masson pine and Camphor pine wood were investigated, including weight gain rate (WPG), moisture uptake, equilibrium moisture content (EMC), anti-swelling efficiency (ASE), parallel-to-grain compressive strength (CS), modulus of rupture (MOR), and mould resistance. The wood samples modified with DMDHEU closely retained their original color and texture, whereas the color of furfurylated wood became dark brown and the texture became clearer. The WPG of DMDHEU-treated wood ranged from 17.9% to 29.3%, which was lower than that of furfurylated wood that ranged from 36.7% to 39.3%. The equilibrium moisture content of DMDHEU-modified wood was slightly higher than the untreated wood, while furfurylation decreased the EMC of wood by approximately 50% compared with the untreated wood. The dimensional stability, parallel-to-grain compressive strength, and mildew resistance of Masson pine and Camphor pine improved after both modifications noticeably. It was concluded that acrylic acid can be utilized as a catalyst to perform wood furfurylation and DMDHEU modification.