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Rubin Shmulsky, Laurice Mara Spinelli Correa, Franklin Quin
Published: 31 July 2021
Abstract:
There is a pressing need to develop engineering standards for timber- and other wood-based mats suitable for supporting construction vehicles, etc. In 2018, a group of mat producers and users began discussing a potential grading standard specific to mats. There are large gaps in the literature regarding the performance of the available raw materials as well as bolt-laminated mat systems. This study addresses the issue of determining the strength and stiffness values of a commercially sourced industrial bamboo mat. A total of seven 8 ft × 14 ft (2.44 m × 4.27 m) commercial bamboo mats were cut into 28 billets that were 21.5 in (54.6 cm) in width. The bamboo mat billets were evaluated for bending stiffness (modulus of elasticity [MOE]) and strength (modulus of rupture [MOR]) using a three-point static bending test. The 5th percentile non-parametric tolerance limit (5% NTL) and design value for fiber stress in bending (Fb) were calculated. The mechanical property values measured for the 3-ply bamboo mat were at least 25% less than values reported for mixed hardwood timber mats. This type of structural performance information is helpful and useful in the development of matting standards, as it describes the minimum performance characteristics for this type of composite matting.
, Aqilah Mohd Tajuddin, Azuan Abdul Latif, Safa Senan Mahmod, Mohd Shaiful Sajab, Masturah Markom, Jamaliah Md Jahim
Published: 29 July 2021
Abstract:
This work aimed to comprehensively examine the pretreatment efficiency of oil palm empty fruit bunches (EFB) using two different types of deep eutectic solvent (DES) mixtures, i.e., choline chloride/imidazole (DES-I) and choline chloride/glycerol (DES-G) in terms of pretreated EFB structural composition and enzymatic hydrolysis. The influence of the pretreatment temperature (55 °C, 90 °C, 125 °C, 160 °C, and 195 °C), EFB to solvent ratio (1:5, 1:10, 1:15, and 1:20), and pretreatment time (2 h, 4 h, and 6 h) on the performance of pretreated EFB and the generated black liquor was examined. The optimal conditions for EFB pretreatment were 160 °C, 1:5 ratio, and 2 h using DES-I solvent, and 160 °C, 1:10 ratio and 4 h using DES-G solvent. The structural carbohydrates of empty fruit bunch pretreated with DES-I, DES-I EFB1 and DES-G, DES-G EFB2 increased to 66.1%, and 64.6%, respectively. The enzymatic hydrolysis of DES-I EFB1 resulted in higher glucan conversion (92.4%) compared to DES-G EFB2, indicating that DES-I solvent was more efficient than DES-G for EFB pretreatment. X-ray diffraction, Fourier transform infrared spectroscopy, and variable-pressure scanning electron microscopy confirmed the removal of lignin and hemicelluloses from EFB during pretreatment and enzymatic hydrolysis.
Ashraf M. Nofal, Mohamed Abd El-Rahman, Asmaa A. Alharbi,
Published: 29 July 2021
Abstract:
Compost tea has a lot of potential for sustainable agriculture. The suppressive effect of compost tea on damping-off disease in beans (Phaseolus vulgaris), caused by Rhizoctonia solani, was investigated. The physicochemical properties of the tested compost tea showed the presence of dissolved solids (7070 mgL-1), organic matter (1280 mgL-1), nitrate (3840 mgL-1), and ammonium (90.0 mgL-1). The concentrations of phosphorus, potassium, calcium, and magnesium in compost tea were 22.7, 1540, 214, and 2.40 mgL-1, respectively. The highest inhibition of R. solani growth at a concentration of 30% compost tea filtrate was 87.0% and it was completely inhibited at a concentration of 50%. The application of compost tea or chemical fungicide (Rizolex-T) significantly decreased the pre- and post-emergence of damping-off and enhanced the plants survival. In spite of the total phenol content in bean plants infected with R. solani (15.6 µg·g-1 fresh weight), the treatment of infected plants using compost tea and the Rizolex-T caused further elevation in the phenol content, to 17.5 and 14.7 µg·g-1 fresh weight, respectively. These findings support the use of compost tea as a potential alternative to synthetic fungicides to help achieve environmental sustainability and food safety in farming.
Haiwei Ren, Li Wang, Yanan Sun, Quanlin Zhao, Yongming Sun, Jinping Li, Bingyun Zhang
Published: 29 July 2021
Abstract:
Effects of cellulase addition were assessed relative to the co-ensiling performance of air-dried corn stover (DCS) and cabbage waste (CW). The DCS and CW mixtures were co-ensiled with 0 to 0.3% of cellulase addition, and changes in composition, intermediates, and biological activity were characterized. The results showed that the addition of cellulase enhanced the decomposition of cellulose and hemicellulose by 2.51 to 6.93% and 3.41%, based on different dosages and compared with the control. Thus, the content of water-soluble carbohydrates increased. The acid content also increased from 5.8% for the control to the range 5.16 to 8.51% for the samples containing cellulase. Moreover, there was a shift from homolactic to heterolactic fermentation with prolonged ensiling time, coupled with the dominant lactic acid bacteria shifting from Paralactobacillus and Lactobacillus to more of Lactobacillus. Thus, the addition of cellulase improved the relative abundance of Lactobacillus. An assessment of fermentation quality, therefore, suggested that cellulase addition can improve the silage quality of DCS/CW during co-ensiling.
Yu Hu, Meng Ling,
Published: 29 July 2021
Abstract:
The removal performance and mechanism of Cr(VI) from aqueous solution was studied for a novel micro-nano particle kraft lignin biochar (BC) pyrolyzed at 400 to 700 °C. The physicochemical properties of BC were determined by Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), and N2 adsorption-desorption isotherms. The results illustrated that the BC had irregular micro- and nanoparticles with abundant pore structure and high BET surface area (111.1 m2/g). The FT-IR results showed that the lower pyrolysis temperature resulted in more oxygen-containing functional groups. The Cr(VI) adsorption capacity decreased with the pyrolysis temperature increasing from 400 to 700 °C, and the maximum percentage removal of Cr(VI) for BC obtained at 400 °C was 100% at pH 2, which suggested that the removal efficiency was mainly dependent on functional groups. Kinetic analysis demonstrated that Cr(VI) adsorption on BC fit well to the pseudo-second-order kinetic model. The adsorption data was well fitted with the Langmuir isotherm models, and the maximum adsorption capacity was 37.2 mg/g at 298K. The BC could be reused twice with Cr(VI) removal of 63.91% and was suitable for Cr(VI) contaminated waste-water treatment.
, Ahmad Samariha
Published: 28 July 2021
Abstract:
The effects of nanoclay were studied relative to the physical, mechanical, optical, and morphological properties of chemimechanical pulping papers. Nanoclay was incorporated at 0%, 2%, 4%, 6%, 8%, or 10%. To increase the retention, 1% cationic starch was used in all test papers. Handsheets (60 g/m2 in weight) were tested to determine their physical, mechanical, optical, and morphological properties. Up to 2% nanoclay increased the tensile strength; at values greater than 2%, the tensile strength decreased. The addition of up to 4% nanoclay increased roughness; between 4% and 10% nanoclay, roughness decreased. With 10% nanoclay, the tear strength, burst strength, and brightness decreased, but the air resistance, opacity, and yellowness increased. Scanning electron microscopy showed that the nanoclay filled the pore spaces between fibers, thus increasing air resistance. X-ray diffraction patterns indicated an intercalated structure.
, Eduardo Luiz Longui, Lech Muszynski
Published: 28 July 2021
Abstract:
Clarinets are made with a variety of materials, e.g., plastic, graphite, porcelain, or even metal. However, the most commonly used material to make clarinets is wood. Today, African granadilla or African blackwood (Dalbergia melanoxylon) is the most popular and most widely used species by leading international companies in terms of clarinet production, because of its high density, color, fine texture, and exceptional durability. This species is also used to manufacture flutes, oboes, and bagpipes, making African blackwood one of the most valuable tree species in the world. However, the focus on the usage of a single species puts considerable pressure on a rare and endangered wood species. Therefore, this work aims to identify viable alternatives to African blackwood in terms of manufacturing clarinets as well as providing a similar combination of instrument characteristics that musicians and companies believe contribute to the value of the instrument, e.g., acoustics, aesthetics, and price.
Guiling Zhao, Chang Liu, Zhaowen Qiu, Zongji Deng, Jinhua Gong
Published: 27 July 2021
Abstract:
A visualization method was used in this work for the 3D morphology of internal defects in wooden products using a Philips Brilliance 16 computed tomography (CT). To obtain a high-quality 3D digital model, the original images from the CT scan were segmented to manually color the cross- and vertical sections of the wooden specimen. Through coloring, the reconstructed model showed the accurate 3D morphology of internal defects, such as cracks, wormholes, and decay parts, as well as clear shapes of borer excrement, nails, bark, and wood parts of the specimen. The results suggest that this method provides precise 3D models of different types of defects in the wooden specimen. It can also accurately measure the size and angle of the defects at any position for further observation. This method can be effectively used for non-destructive testing of wooden products and wooden cultural relics and can provide accurate scales of defects and intuitive 3D models for wooden products and wooden cultural relics restoration.
, Martin Böhm, Jana Nábělková, Robert Černý
Published: 26 July 2021
Abstract:
Methylxanthine’s fungicidal properties were investigated, with attention to the temperature of treatment. Caffeine and theophylline treatments of beech and spruce woods were applied for three months in the temperature range of -20 to 40 °C, simulating potential weather conditions in the European region and temperatures specific for various wood applications (cellars, wine cellars, room indoor temperatures, interior trusses). Effects of the selected temperatures were considered without the influence of the other possible factors, which have been considered in previous studies (e.g. effects of temperature in combination with other factors such as UV radiation, humidity, and chemical or biological degradation). Then, the specimens were exposed to a mix of molds and fungi for three months under controlled laboratory conditions in order to analyze a possible subsequent biological attack. The results did not show any effect of temperature of the methylxanthine treatment within the studied range on the organismal activity. Caffeine exhibited a better protective potential than theophylline and was more effective for spruce than for beech. The results indicated the suitability of caffeine for protection of spruce and spruce-based materials in interior applications at a stable temperature without significant effects of UV and humidity.
, Anna Jankowska, Robert Kłos, Joan Knudsen, Sari Merilampi, Elina Priedulena
Published: 26 July 2021
Abstract:
Furniture manufacturers’ response to the demographic challenge of aging nations is an important issue. The number of seniors is rising worldwide. The aging process often results in multiple health implications, including weaker mobility, decrease in muscle mass, and change in anthropometrical dimensions of the human body. Thus, the furniture offered should be adjusted to the needs of an increasing group of senior customers. To identify seniors’ preferences in relation to characteristics of sitting furniture, international surveys with 627 respondents aged 60+ years were conducted in Poland, Germany, Denmark, Finland, Latvia, and Lithuania. The implementation of this data in the design process may result in creation of the market offer meeting seniors’ needs. Design and functionality features were examined to provide guidance for senior-friendly development of furniture for sitting. Among the most important findings is the clear preference of having an armchair with the high backrest reaching above the head, a chair with armrests and an upholstered backrest and seat. Furthermore, respondents paid attention to the durability of furniture, stain resistance of upholstery, and adaptation of the furniture to the user’s dimensions, e.g., having influence on the height and depth of the seat before the purchase.
Somwang Khantayanuwong, Wisanee Boonpitaksakul, , Sawitree Pisutpiched, Buapan Puangsin
Published: 25 July 2021
Abstract:
There have been recent attempts to revive the traditional production of handmade paper from the bark of the Coi (Streblus asper Lour.) tree in Thailand. A sheet sample of Coi handmade paper, made from the traditional production, was collected and examined microscopically for the first time. Film-like material and cubic calcium particles were found on the sheet sample surface, which is consistent with the results of the authors’ previous research. Meanwhile, handsheets derived from Coi pulp fiber, freshly made in the laboratory, demonstrated a low air permeance and brightness with high opacity due to the film-like material and cubic calcium particles. With a high felting power of Coi pulp fiber coupled with a possible strengthening role of the film-like material, both the beaten and unbeaten fibers were used to form handsheets with high strength. Some potential aspects of Coi pulp fiber suitable for creating a unique Thai banknote paper have been demonstrated, for which further studies are suggested.
Xinghuan Wu, Jiangang Zhu, Xu Wang
Published: 25 July 2021
Abstract:
Reducing carbon emissions is the direction various industries will head in the future. Solid wood furniture products that occupy important market shares have high carbon reduction potential. This article briefly describes the carbon footprint of the solid wood furniture production process. In addition, it analyzes the feasible carbon reduction technologies applicable during the design and manufacturing process through the potential emission reduction-oriented approach, ranging from the upstream raw materials to overall power consumption. The primary carbon reduction potential points entail the high efficiency and reuse of primary materials, the reduction of auxiliary materials, and the optimization of solid wood processing based on spraying and dust removal. In this study, the carbon reduction design of solid wood furniture primarily covers the design methods, material selection, structural design, and packaging design. The carbon reduction manufacturing technology was analyzed from a process, equipment, and management aspect. It is hoped that this study can provide a reference for the future strategic design of solid wood furniture companies, which will promote low-carbon development in the wood furniture industry.
, Yuting Liu, Chang Liu, Simin Yi, Wen Sun, Jianfeng He
Published: 23 July 2021
Abstract:
Catalytic systems were investigated for the ethanolysis of expired food into 5-ethoxymethylfurfural (5-EMF). Fructan-rich expired food (expired probiotics beverage powder, onion powder, garlic powder, and burdock tea), and starchy expired food (expired steamed buns and egg yolk battercake) were tested as starting substrates. Optimization of the reaction conditions included varying the catalyst type, temperature, catalyst loading, and reaction time to maximize 5-EMF yield. Several co-solvents were added to evaluate their impact on the generation of 5-EMF. The selected expired foods produced 5-EMF yields ranging from 0.2 mol% to 68 mol%. The 5-EMF yield from fructan-rich expired food was more noticeably affected by the content of the non-carbohydrate part than that from starchy expired food. The effect of co-solvents on conversion efficiency was closely related to the catalyst type but was not strongly correlated with the feedstock used. This study provides a facile way to produce biofuel chemicals from carbohydrate-rich expired food.
Jaša Saražin, Bogdan Šega,
Published: 22 July 2021
Abstract:
The characterization of the curing process allows the determination of the optimal pressing parameters, which is essential for the economical production of wood-based composites. In this study, an automated bonding evaluation system (ABES), dielectric analysis (DEA), and dynamic mechanical analysis (DMA) were used to determine the curing parameters of biobased pine tannin-hexamine adhesive at five temperatures ranging from 75 to 175 °C. This study aimed to compare the three above methods and to find correlations between them. All methods showed the same trend of the curing process, which became faster with increasing temperature. Due to various heating rates among the different methods, the curves representing the degree of cure were shifted to the left for the period in which nearly isothermal conditions were reached. It was determined that these methods could be mutually comparable. The ABES was regarded as the reference method; the DEA was regarded as a method that overestimates the curing process and that describes the beginning of the curing process more precisely; and the DMA method was regarded as a method that underestimates the curing process and that describes the end of the curing process more precisely. Linear trend lines were found between the observed methods.
Chuan Li Lee, , Paik San H'Ng, Pui San Khoo, Luqman Abdullah Chuah
Published: 22 July 2021
Abstract:
The efficacy of additional water-soluble additives was studied relative to the physical and mechanical properties of particleboards produced from oil palm empty fruit bunch (OPEFB). Polyethylene glycol, acrylamide, and acrylic resin were selected as water-soluble additives for use in the OPEFB particleboard production process. The effects of the three additives at two different concentrations (2% and 4% of dry OPEFB mass) on the particleboard properties were evaluated. Addition of water-soluble additives increased the performance of the OPEFB particleboard. The additive concentration has a significant effect on the properties of the particleboard. With the increase of additive concentration, the internal bonding and modulus of rupture value increased while the thickness swelling and water absorption decreased. Particleboards with an additional 4% of acrylamide or polyethylene glycol achieved the highest modulus of rupture (22 MPa), highest internal bonding strength (1 N/mm2), and lowest thickness swelling (9%). All the particleboards produced with 4% of water-soluble additive achieved the standard requirements of JIS A 5908:2003 for physical and mechanical properties.
Izabela Betlej, , Damian Dubis, Jacek Wilkowski, Krzysztof J. Krajewski, Janusz Zawadzki
Published: 21 July 2021
Abstract:
This study examined how nutrients present in the growth environment of microorganisms forming a consortium of bacteria and yeasts, called a symbiotic culture of bacteria and yeast (SCOBY), affect the efficiency of cellulose synthesis and selected properties of the cellulose, such as gloss and color. The results showed that nitrogen-rich ingredients, such as peptone and green tea, increased the efficiency of polymer synthesis and determined the cellulose’s gloss. This research showed that the qualitative characteristics of bacterial cellulose can be easily modified by the appropriate selection of the components of the culture media.
Youngsang Chun, Soo Kweon Lee, Hah Young Yoo, Seung Wook Kim
Published: 21 July 2021
BioResources, Volume 16, pp 6512-6547; https://doi.org/10.15376/biores.16.3.chun

Abstract:
Biochar is highly valuable in various applications due to its unique physicochemical properties such as high thermal efficiency, high surface area, surface functional groups, and crystal structure. The goal of this review is to establish a systematic strategy of biochar production for applications in various fields. First, the characteristics of biomass as feedstock for biochar production and their classification are discussed according to the types present in nature. Second, the technology for biochar production and the production yield are examined. In thermochemical conversion for biochar production, five major types of pyrolysis processes are suggested, and the production yield is evaluated according to pyrolysis parameters (feedstock pretreatment, operating temperature, heating rate, residence time, carrier gas). In addition, biochar production from pyrolysis of mixed feedstock has recently been suggested; thus, the evaluation of the production yield from co-pyrolysis is included. Finally, analytical techniques for biochar characterization are investigated and the application of biochar in various fields is considered, such as in adsorbents, energy storage devices, and catalysts.
Deshan Yang, Ming Xu, Zhongfan Chen
Published: 21 July 2021
Abstract:
Chinese traditional timber frames are known for their mortise-tenon joints and wooden planks shear walls. To investigate the seismic behavior of the structural system, three full-scale timber frames were subjected to in-plane quasi-static loading. The hysteresis characteristics, lateral load-carrying capacities, lateral stiffnesses, and energy dissipation capacities of the timber frames were investigated. The results showed that the hysteretic loops of all specimens exhibited pinching, and the column and beam components were nearly intact after the test. The traditional wooden frames had large deformability. The installation of the infilled timber shear wall brought great improvements in lateral resistance and energy dissipation to the bare frames. The initial stiffness of the timber frame infilled with timber shear wall was 0.113 kN/mm, which was 56.9% and 11.9% greater than those of the bare frame specimen F1 and specimen F2, respectively. The results from the experimental analyses can serve as a technical basis for the development of seismic design methods and strengthening designs of such structures in practical engineering.
Zakiah Sobri, , Norzita Yacob, Paik San H'Ng, Luqman Chuah Abdullah, Edi Syams Zainudin
Published: 20 July 2021
Abstract:
An approach of green in situ synthesis single-step method was applied to produce antibacterial paper. The objective was to investigate the effect of precursor addition on the formation of zinc oxide particles using an in situ single-step method. Zinc chloride concentrations of 0.1, 0.3, 0.5, and 0.7 M were prepared and added into a solution of algae extract and bamboo pulp. The prepared pulps were tested and made into handsheets using a papermaking machine based on TAPPI T205 (2006). Morphological observation of treated papers was conducted using a field emission scanning electron microscope (FESEM). An average of 400 to 570 nm zinc oxide spherical-shaped particle was observed on the fibers of paper. The percentage of element composition of the treated paper were 15.08% to 34.08% of zinc and 17.45% to 32.59% of oxygen captured via scanning electron microscopy with energy dispersive X-ray (SEM-EDX) analysis. The crystallinity test was performed using X-ray dispersion (XRD). A higher percentage of precursors exhibited a more amorphous structure. A measurement of more than 30% increment of inhibition zone was obtained from 10.00 to 25.00 mm against S. aureus, S. choleraesuis, and E. coli. Precursors addition of more than 0.3 M would have the most potential to enhance the growth of zinc oxide via in situ preparation, hence providing better antibacterial properties of the prepared papers.
Juan J. Gonzalez, Brian Bond, Henry Quesada
Published: 19 July 2021
Abstract:
Research indicates that users of thermally modified wood lack information regarding the improved performance and any variations that may exist for the “same” product when manufactured by different companies. The goal of this study was to evaluate the variability in mechanical properties of three thermally modified hardwoods and determine the variability between three different manufacturers. To determine the hardness, bending (modulus of elasticity and module of rupture) and shrinkage values, testing was conducted following ASTM standard D143. The samples were conditioned at 20 °C and a relative humidity of 65% until they reached an equilibrium moisture content before testing. Analysis of variance was used to determine the variability within and between the different processes used by each company. Seven out of 18 (39%) tests indicated that there were statistical differences regarding the mechanical performances of the wood samples. Yellow poplar had the least variation between companies (only difference in equilibrium moisture content, EMC) and red maple had the most (hardness, tangential shrinkage, and EMC). While the means for these properties were statistically different, the differences in application for hardness and EMC are slight. For example, the largest difference between processes in hardness was 83.6 kg, for tangential shrinkage, 0.45% and 1.37% for EMC. These differences are suggested to be inconsequential when compared to the values that exist between different species of untreated wood.
Yinan Hao, Yanfei Pan, Qingwei Du, Xudong Li,
Published: 19 July 2021
Abstract:
Armeniaca sibirica shell activated carbon (ASSAC) magnetized by nanoparticle Fe3O4 prepared from Armeniaca sibirica shell was investigated to determine its adsorption for Hg2+ from wastewater. Fe3O4/ASSAC was characterized using XRD (X-ray diffraction), FTIR (Fourier transform infrared spectroscopy), SEM (scanning electron microscopy), and BET (Brunauer–Emmett–Teller). Optimum adsorption parameters were determined based on the initial concentration of Hg2+, reaction time, reaction temperature, and pH value in adsorption studies. The experiment results demonstrated that the specific surface area of ASSAC decreased after magnetization; however the adsorption capacity and removal rate of Hg2+ increased 0.656 mg/g and 0.630%, respectively. When the initial concentration of Hg2+ solution was 250 mg/L and the pH value was 2, the adsorption time was 180 min and the temperature was 30 °C, and with the Fe3O4/ASSAC at 0.05 g, the adsorption reaching 97.1 mg/g, and the removal efficiency was 99.6%. The adsorption capacity of Fe3O4/ASSAC to Hg2+ was in accord with Freundlich isotherm models, and a pseudo-second-order kinetic equation was used to fit the adsorption best. The Gibbs free energy ΔGo < 0,enthalpy change ΔHo < 0, and entropy change ΔSo < 0 which manifested the adsorption was a spontaneous and exothermic process.
Mei Yun Chin, , Kuok King Kuok, Wai Yun Chiew, Muhammad Khusairy Bin Bakri
Published: 16 July 2021
Abstract:
Partial replacement with coconut shell coarse aggregates was studied as a means to produce lightweight coconut shell concrete (CSC). Coconut shell concrete is a structural grade lightweight concrete that has a lower self-load compared to the normal weight concrete (NWC), which allowed the production of larger precast units. An experimental study and analysis were conducted using different volume percentages of 0%, 10%, 30%, 50%, and 70% of coconut shell as coarse aggregates, to produce M30 (30 MPa) grade concrete. The compressive strength of the NWC and CSC were obtained on the 7th and 28th day. The optimum results obtained for M30 grade concrete at 7th and 28th day of CSC were 34.2 and 38.6 MPa, respectively. In addition, the workability and weight-reduction were analyzed and compared with NWC. Scanning electron microscopy (SEM) with energy dispersive X-ray spectroscopy (EDS/EDX) and Fourier transform infrared spectroscopy (FTIR) were also used to investigate the structural morphology, chemical composition, and infrared functional groups of the concrete.
Weikai Wang, Minghan Li, Jiabin Cai
Published: 16 July 2021
Abstract:
In order to study the effects of a messmate heartwood extraction process on its cell wall pore structure and its drying ability, its nanopore structure was explored after via gas adsorption technology. Specifically, the messmate heartwood particles were extracted with methanol, and then the cell wall pore structure of the original and extracted samples were evaluated by N2 and CO2 sorption and pycnometer methods, respectively. Overall, compared with the original samples, the cell wall porosity, micropore volume, mesopore volume, BET specific surface area, and specific surface area of the micropores of the extracted messmate heartwoods increased by 2.55%, 0.007 cm3/g, 0.0014 cm3/g, 0.24 m2·g-1, and 21.9 m2·g-1, respectively. The cell wall pore volume measured via the gas adsorption method was smaller than the measurement from the pycnometer method. The results indicated that the presence of extractives made the messmate cell wall have a decreased pore volume and porosity, which may be one of the reasons messmate wood is difficult to dry. Messmate extractives primarily were present in the micropores of the cell wall in the range of 0.4 nm to 0.7 nm. However, gas sorption technology could not detect all the pores in the cell wall of the messmate heartwood sample.
, Takuji Miyamoto, Sukma S. Kusumah, Soichi Tanaka, Toshiaki Umezawa, Kozo Kanayama, Kenji Umemura
Published: 15 July 2021
Abstract:
This study investigated the effects of adding ammonium dihydrogen phosphate (ADP) on the physical and chemical changes of a water-soluble extract of the inner part of oil palm trunk (OPT) to clarify the bonding mechanism of the binderless particleboard. The extract’s effect on ADP-added binderless particleboard was also investigated. OPT particles were treated by hot water at 60 °C for 6 h. Water-soluble extract and treated OPT particles were obtained. ADP was added to the water-soluble extract at 0, 10, and 40 wt%, and the mixtures were heated at 180 °C for 10 min. Furthermore, binderless particleboards using the treated particles were manufactured with similar condition. The 10 wt% ADP mixture changed the water-soluble extract to an insoluble substance, which was twice that of with 0 wt.% ADP addition. Infrared spectroscopy revealed peaks of furan and carbonyl in the insoluble substance. This indicated that the free sugar content in the water-soluble extract would change to furan compounds. Thermal analysis revealed that the resulting insoluble substance had good thermal stability, suggesting a high-molecular-weight substance. The insoluble substance would contribute to bonding of the binderless particleboards. In particular, a significant contribution to the water resistance was observed.
Crisel A. Mejía-Rivas, Ana M. Bailón-Salas, Luis A. De la Peña-Arellano, María D. J. Rodríguez-Rosales,
Published: 15 July 2021
Abstract:
Agro-industrial waste is generated in large quantities, producing negative environmental impacts. For instance, in the distillation process of vinasses, up to 15 L are produced per alcohol produced. Therefore, it is necessary to search for ecological alternatives. Biological treatments are not recommended because vinasses contain compounds, such as melanoidins, which exert inhibitory activity against microorganisms. Thanks to this activity, melanoidins could be removed, recovered, and become a value-added product. In this study, Opuntia ficus-indica (OFI) mucilage, a natural biopolymer as coadjuvant, was used to improve the coagulation-flocculation process in the treatment of real samples of mezcal vinasses, after evaluating the individual effect of aluminum sulfate and ferric chloride. It was possible to eliminate 90% of color using ferric chloride, showing better removals than aluminum sulfate. However, the effect of ferric chloride plus OFI mucilage generated an adverse effect because the removal was under 17%. The individual effect of ferric chloride for chemical oxygen demand (COD) removal was 28%. This removal was improved by the addition of OFI mucilage, as it was able to increase removal to 84%. The natural coadjuvant was shown to be effective in the COD removal in the treatment of mezcal vinasse using the coagulation-flocculation process.
Ruidong Wang, Xia Yang, Yong Gao, Xiaohong Dang, Yumei Liang, Shuai Qi, Chen Zhao, Xiaoting Duan
Published: 13 July 2021
Abstract:
Salix psammophila has been extensively used as a sand barrier material for various desertification control applications. Elucidating the long-term decomposition characteristics and nutrient cycling process of this sand barrier in desert environments is of great importance. In this study, which was conducted for 1 to 9 years, changes in the mass loss percentage and the residual percentage in the decomposition process were explored of S. psammophila sand barriers in arid Northwestern China. In addition, the S. psammophila analysis nutrient elements release rule and its influence on soil properties were evaluated. The results showed that the decomposition process of S. psammophila sand barriers exhibited a “slow-fast” trend. After decomposition time for 9 years, mass decreased remarkably, and the residual percentage was 33.6%. Further, the nutrient release characteristics differed. C, P, and K were in the release state, whereas N was in the enrichment state. The decomposition percentage of the sand barriers was significantly correlated with N, P, K, C/N, C/P, and N/P (p < 0.05). The soil nutrient contents of C, P, and K contents increased 3.43, 2.23, and 2.08 g/kg compared to the initial values, respectively. The soil nutrient contents of N contents decreased 0.19 g/kg.
Peng Cheng, , Shi Ke
Published: 13 July 2021
Abstract:
The specific energy absorption of a thin-walled tube can be improved by filler. This study examined the potential use of a cheaper biomass filler, paper scraps, to enhance the energy absorption characteristics of the structure while reducing its cost, compared to that with a traditional filler such as foam material. Quasi-static crushing tests and finite element simulations were performed by using the explicit non-linear finite element software LS-DYNA to determine the improvements to the mean crushing force and specific energy absorption of the steel tube when filled with different densities of paper scraps. The mean crushing force and specific energy absorption of the empty tube, the paper scraps, and thin-walled tube filled with paper scraps were determined, and corresponding numerical simulations were performed. The simulation and test results showed that the impact performance of tube filled with paper scraps was greatly improved when paper scraps density was 0.35 g/cm3. By optimizing paper scraps filling structure, a new structure that could further enhance the specific energy absorption was obtained. The optimal scheme could increase the specific energy absorption of Q345 steel tube by 11.35%.
Published: 13 July 2021
Abstract:
To investigate the effect of sodium alginate (SA) on the properties of wheat straw/polylactic acid (PLA) composites, four kinds of composites with different SA contents (0 wt%, 5 wt%, 10 wt%, and 15 wt%)were prepared via injection molding. The mechanical properties, moisture absorption, thermal stability, and infrared spectrum of the four kinds of composites were tested and analyzed, and the microstructure of the tensile section of the composites was observed via scanning electron microscopy. The degradability of the composites was also analyzed. The results showed that the wheat straw/PLA composites with 5% SA had better mechanical properties. Their tensile strength was 15.8%, 5.4%, and 19% higher than those of 0%, 10%, and 15% SA, respectively. The impact strength of the 5% SA composites changed to an acceptable degree relative to the non-SA composites, which had an impact strength of 28% lower than that of 0% SA but 51.9% higher than that of the 15% SA composite. The 5% SA composites had less hygroscopicity and better thermal stability, and adding SA enhanced the degradability of the composites. As the SA content increased, degradability increased greatly.
Bin Yang,
Published: 13 July 2021
Abstract:
The disposal of automotive shredder residue (ASR) directly affects China’s goal of achieving a 95% recycling rate for end-of-life vehicles. Pyrolysis and gasification have gradually become the most commonly used thermochemical technologies for ASR recycling. To obtain more hydrogen-rich syngas, it is necessary to determine the optimal process parameters of the ASR pyrolysis and gasification process. The main process parameters of the two-stage ASR pyrolysis and gasification process were studied using the established Aspen Plus model. Through analyzing the effects of process parameters, such as the temperature, equivalence ratio, and mass ratio of steam to ASR feedstock, on the product distribution and product characteristics of ASR pyrolysis and gasification, the optimal process parameters were determined. A series of comparative experiments under different conditions were conducted. The experimental results verified the accuracy and reliability of the Aspen Plus simulation model for the ASR pyrolysis and gasification processes and verified the practical feasibility of the process parameters obtained from the simulation analysis.
Maria Juliane Suota, Débora Merediane Kochepka, Marlon Gualberto Ganter Moura, Cleverton Luiz Pirich, Mailson Matos, Washington Luiz Esteves Magalhães,
Published: 12 July 2021
BioResources, Volume 16, pp 6471-6511; https://doi.org/10.15376/biores.16.3.suota

Abstract:
Lignin is one of the most important and widespread carbon sources on Earth. Significant amounts of lignin are delivered to the market by pulp mills and biorefineries, and there have been many efforts to develop routes for its valorization. Over the years, lignin has been used to produce biobased chemicals, materials, and advanced biofuels on the basis of its variable functionalities and physicochemical properties. Today, lignin’s applications are still limited by its heterogeneity, variability, and low reactivity. Thus, modification technologies have been developed to allow lignin to be suitable for a wider range of attractive industrial applications. The most common modifications used for this purpose include amination, methylation, demethylation, phenolation, sulfomethylation, oxyalkylation, acylation or esterification, epoxidation, phosphorylation, nitration, and sulfonation. This article reviews the chemistry involved in these lignin modification technologies, discussing their effect on the finished product while presenting some market perspectives and future outlook to utilize lignin in sustainable biorefineries.
Minjay Chung, Sensung Cheng, Chunya Lin, Shangtzen Chang
Published: 12 July 2021
Abstract:
This study focuses on volatile aromatic constituents extracted using solid-phase microextraction (SPME) from underground and aboveground Bambusa oldhamii shoots. Analysis was conducted using the extracts after heating at various temperatures and for various durations. Results of gas chromatography-mass spectrometry (GC-MS) revealed six SPME-extracted volatile aromatic compounds in underground B. oldhamii shoots and eleven in aboveground B. oldhamii shoots. Methyl salicylate with a characteristic mint aroma and methoxy-phenyl oxime that gives a smell of fresh shrimp and crabs are the main volatile compounds found in underground and aboveground shoots of B. oldhamii, respectively. Moreover, the two types of shoots tested also contain volatile compounds including fatty acids: n-hexadecanoic acid (27.94%) and aliphatic aldehyde: trans-2-nonenal (16.31%), respectively. The GC-MS analysis of underground and aboveground B. oldhamii shoots steamed at 100 C for 60 min revealed n-hexadecanoic acid as the main fatty acid compound.
Ting Jiang, Xiaoyan Feng, Rui Xu, Sheng Dong, Meiyan Wu, , Weimin Lu,
Published: 12 July 2021
Abstract:
Large amounts of solid residues are generated after extraction of active ingredients from herbs for the production of natural medicine, but the residues have not been well utilized. In this work, cationic nanofibrillated cellulose (CCNF) was prepared from the solid residues of Astragali Radix by etherification and homogenization. The CCNF was mixed with sodium alginate (SA) to create a hydrogel dressing by physical interactions between CCNF and SA without any addition of cross-linker. The CCNF-SA dressing exhibited moderate viscosity, good moisture-maintaining property, great antibacterial activities, good cytocompatibility, and clear acceleration of wound healing on rats. Furthermore, this CCNF-SA dressing with nanofibrous structure had moderate air permeability. Therefore, the CCNF-SA hydrogel could be used potentially as a skin wound dressing. Development of cost-effective and bioactive wound dressing materials is of crucial importance to reduce the burden on patients and healthcare systems. Also, this work provides a new strategy for valorization of the solid residues of herbs.
Huang-Fei Lv, Mei-Ling Chen, Cai-Ping Lian, Hui Li, Shu-Min Yang, Bin Xu, Ben-Hua Fei
Published: 12 July 2021
Abstract:
Characterized by its light weight, high strength, and good flexibility, round bamboo is a natural functional biomaterial with a multi-level structure. Cracking is a key factor hindering its wider application. Moisture changes cause cracking when the round bamboo is dried. Therefore, studying moisture variations in the drying process of round bamboo can effectively reduce or solve the cracking problem. In this study, microwave drying with computer tomography (CT) imaging technology was used to understand the distribution and migration of moisture in round bamboo in the course of drying. The results indicated that water content has a significant correlation with the CT value, which can be used to achieve rapid determination of water content. The radial water content of samples gradually decreased from bamboo green (outer) to bamboo yellow (inner). The axial water content was high in the middle and low on both ends. As the water content decreased, the axial moisture distribution was consistent. The internode moisture mainly moved from the junction of bamboo yellow and bamboo partition, entered the adjacent cavity, and then gradually moved outward. Thus, the microwave drying method can effectively achieve industrial drying of round bamboo and prevent cracking.
, Rika Raniya, Triyani Fajriutami, Apri Heri Iswanto, ,
Published: 9 July 2021
Abstract:
Sweet sorghum bagasse (SSB) is potential feedstock for bioethanol production due to its natural abundance and high cellulose content (> 40%). This work compared the impact of three variables relative to the enzymatic hydrolysis of SSB kraft pulp. The three variables were the biosurfactant from lignin derivative known as amphiphilic lignin derivatives (A-LD), the enzyme loading level, and the hydrolysis time. These variables were optimized by response surface methodology (RSM) with a Box-Behnken design (BBD). The concentration of polyethylene glycol (PEG) 4000 was also optimized to compare it with the A-LD performance in the enzymatic hydrolysis process. After optimization, the A-LD produced a higher reducing sugar yield (RSY) (99.45%) than the PEG 4000. The difference in the predicted versus experimental values of the RSY was less than 4%, which means that the model was highly predictive. The adequacy of the model was confirmed by a regression value close to 1 for the A-LD assisted test. The result implies that the A-LD significantly improved the enzymatic hydrolysis performance to enhance the RSY. Moreover, the BBD is adequate and useful to identify the optimum concentration of surfactant.
Yunyi Guan, , Xiong Jiang, Binhao Xu, Pingyi Liu, Haitao Li
Published: 9 July 2021
Abstract:
Bamboo is mainly grown in hilly areas, and the harvesting of bamboo basically relies on labor. Moreover, the bamboo is prone to splitting problems during harvesting. To liberate labor and improve work efficiency, the crack propagation principle of bamboo was studied. Based on this study, a new cutting scheme using spiral feed was proposed. Additionally, a new bamboo cutting mechanism was designed. The new cutting mechanism, when installed on a harvesting vehicle, can automatically complete the cutting operation. The cutting mechanism is different from the traditional ones, and it uses four sets of saw blades for spiral feed cutting around the bamboo, which can reduce the splitting probability during the cutting process. Finally, a solid model of the cutting mechanism was built, and the basic movement process was simulated to verify the feasibility of the bamboo cutting mechanism.
Nurcan Yigit, Zuhal Mutevelli, Hakan Sevik, , Halil Baris Ozel, Mehmet Cetin, Cagri Olgun
Published: 9 July 2021
Abstract:
Climate-dependent changes in wood anatomical characteristics were studied for Rosa sp. and Nerium oleander sp. grown in phytosociological areas. For this purpose, wood samples were taken from the individual wood species grown in Antalya, Eskisehir, and Kastamonu provenances, where Terrestrial, Black Sea, and Mediterranean climate types prevail, and 11 anatomical characters were identified or calculated. As a result of the study, it has been determined that the climate has large effects on the characteristics that are the subject of the study and that each characteristic is at a higher level in individuals grown in areas where different climate types prevail. The highest values in Rosa species were obtained in the individuals grown under Terrestrial climate type in all characteristics except for LW (lumen widths), EC (elasticity coefficients), and FF (F-Factors.) Whereas in Nerium oleander, the highest values were obtained in individuals grown in the Mediterranean climate type in FL (fibre lengths), LW (lumen widths), FR (felting ratios), and EC (elasticity coefficients). For the same species type, in the Terrestrial climate, RIJID (rigidity coefficients), MUHT (Muhlstep ratios), and RUNK (Runkel ratios), and in the Black Sea climate DWT (double wall thicknesses) and WT (wall thicknesses) characteristics had high values.
Ajith K. A. Gedara, Iva Chianella, Jose L. Endrino,
Published: 8 July 2021
BioResources, Volume 16, pp 6448-6470; https://doi.org/10.15376/biores.16.3.gedara

Abstract:
Most industrially used synthetic wood adhesives release formaldehyde, which is carcinogenic for humans. Adhesiveless bonding of wood can be achieved using heat treatment by either hot-pressing method, suitable mainly for wood particles and fibres or by wood welding. Welding of wood, which relies on the heat generated via friction, can be used for bonding two or more solid wood pieces together. The process can be carried out either by linear or rotational wood welding. This review first considers the manufacturing of binderless wood-based panels by hot-pressing. Then this is followed by an in-depth outlook of wood welding and its application in the wood industry. The effects of varying wood welding parameters, such as applied pressure, vibrational frequency and amplitude, holding pressure, holding time, welding time in linear wood welding, and relative diameter difference between the substrate and the dowel in rotational wood welding to obtain joints with optimal mechanical and physical properties is reviewed and discussed. Wood products made by heat treatment (hot-pressing and wood welding) are environmentally friendly, and the brief curing times needed for their manufacture represent a great advantage compared with the usage of wood adhesives to bind pieces of wood.
, Adam Redman, William Leggate, Robert L. McGavin, Tony Dakin
Published: 7 July 2021
Abstract:
Non-destructive evaluation methods for timber stiffness are gaining increased interest as an alternative to static testing since they can be fast, cost-effective, and transportable, as well as non-destructive. The objective of this study was to evaluate the accuracy and limitations of a newly developed smartphone application (SMART THUMPER™) for the non-destructive evaluation of timber stiffness properties. The study determined the effect of the length, density (species), and cross-section sizes of the timber samples on the stiffness results. The results were compared to beam identification by non-destructive grading (BING©), an existing commercial non-destructive testing technology for evaluating the mechanical quality of wood and other materials. It was found that the application can be used to reliably estimate the stiffness of various timber products with a resonance frequency value below 2000 Hz. Frequencies greater than 2000 Hz were found to induce errors due to the smartphone microphone, which is engineered to acquire a lower frequency range. A reliability matrix providing an indication of the accuracy of SMART THUMPER™ estimation was presented, which may also prove useful in selecting appropriate sample lengths prior to testing. The sample length or dimensions can be manipulated to lower the frequency, and hence, to improve the results.
Wen-Yu Qi, Cai Liu, Xiao-Lian Wu, Ji-Qing Li, , Jin-Guo Lin
Published: 6 July 2021
Abstract:
Castanopsis fargesii is among the most prevalent hardwood species in South China. To improve the poor dimensional stability of C. fargesii wood, heat treatments were performed using vacuum or sand as the medium at four temperatures from 170 °C to 215 °C for 4 h. As a medium, vacuum or sand can create a low oxygen environment. The results showed that, as the temperature increased, the oven-dry density decreased, whereas the dimensional stability and the total color change (∆E*) increased with both media, two different changing patterns of a* and b* were observed, the lignin content increased, and the holocellulose content decreased. The oven-dry density decreased 9.4% and 25.5%, volume shrinkage ratio decreased 27.8% and 37.7%, and the ∆E* was 19.63 and 45.52, the lignin contents increased from 17.62% to 28.62% and 42.87%, and the holocellulose contents decreased from 80.49% to 69.43% and 51.04% when C. fargesii wood was heated under vacuum and with sand at 215 °C, respectively. Overall, sand heat treatment affected wood physical and chemical properties more than vacuum heat treatment. The analysis of functional groups and crystallinity also showed that there were severe changes in C. fargesii wood under sand heat treatment.
Yating Wang, Xiaochun Chen, Yaqi Liang, Chenghua Yu
Published: 2 July 2021
Abstract:
Despite previous efforts, the fabrication of superhydrophobic substrate via an environment friendly and easy approach remains a great challenge. In this study, a low cost, simple, and green procedure was developed to prepare a superhydrophobic paper surface that is acceptable for the papermaking industry. First, a wax mixture (beeswax & carnauba wax) was emulsified and coated on the filter paper surface. Then, the coated paper was annealed at different temperatures. The further heat-treatment-rendered wax-coated paper hydrophobic or superhydrophobic because submicrometer or micrometer wax structures were present on the paper surface. The water contact angle of the annealed filter paper sample reached 151.5° at 60 °C, and the sliding angle was under 10°. Further, the relationship between surface composition and the hydrophobic properties of the coated paper samples was discussed. The obtained paper samples showed great potential in water/oil separation, as they had an efficiency over 99%. This work proposed a new simple and mild approach to fabricate superhydrophobic filter papers and explored the hydrophobicity and water/oil separation properties.
Ji-Soo Park, Chan-Woo Park, Song-Yi Han, Eun-Ah Lee, Azelia Wulan Cindradewi, Jeong-Ki Kim, Gu-Joong Kwan, Young-Ho Seo, Won-Jae Youe, Jaegyoung Gwon, et al.
Published: 2 July 2021
Abstract:
Cellulose nanocrystals (CNCs) were wet-spun in a coagulation bath for the fabrication of microfilaments, and the effect of sodium alginate (AL) addition on the wet-spinnability and properties of the microcomposite filament was investigated. The CNC suspension exhibited excellent wet-spinnability in calcium chloride (CaCl2) solution, and the addition of AL in CNC suspension resulted in the enhancement of the wet-spinnability of CNCs. As the AL content increased from 3% to 10%, the average diameter of the microcomposite filament decreased, and its tensile properties deteriorated. The increased spinning rate caused an increase in the orientation index of CNCs, resulting in an improvement in the tensile properties of the microcomposite filament.
Lingyu Zeng, Yecan Peng, Guirong Ye, Xiaona Shang, Shuangfei Wang, Jinghong Zhou
Published: 2 July 2021
Abstract:
The secondary treated effluents of pulp and paper mills contain high chemical oxygen demand (COD) that is associated with organic matter. Therefore, this study explores the adsorption of substances contributing to COD using CoFe2O4 and quartz sand-coated CoFe2O4 in batch and fixed-bed column experiments. X-ray diffraction, scanning electron microscopy, Brunauer–Emmett–Teller analysis, and X-ray photoelectron spectroscopy were used to characterize the adsorbents. The quartz sand-loaded CoFe2O4 exhibited a larger pore volume and average pore size. Batch experiments revealed that adsorption on CoFe2O4 closely fit the pseudo-second-order model. To explore the effects of bed depth, feed flow rate, and initial solution pH on the breakthrough characteristics of CoFe2O4-coated sand, fixed-bed column experiments were conducted, and the breakthrough curves were drawn from the ratio of influent COD concentration to effluent COD concentration. The breakthrough time decreased with an increase in the feed flow rate and initial pH but increased with the bed depth. According to the X-ray photoelectron spectroscopy analysis, CoFe2O4-coated sand showed excellent stability due to negligible leaching of metallic elements. These findings have important implications for the advanced treatment of industrial wastewater.
Claire Monot, , Quentin Charlier, Julien Bras, David Guérin, Barthélémy Harthong, Didier Imbault, Robert Peyroux, Martine Rueff, Laurence Leroy, et al.
Published: 1 July 2021
Abstract:
Today’s environmental concerns are pressuring industries to substitute paper-based materials in place of plastics in many sectors including packaging. However, assembling papers and paperboards using environmentally friendly solutions remains a technological challenge. In this context, ultrasonic (US) welding is an alternative to adhesives. In this work, the potential of US welding to assemble folding boxboards was investigated. Folding boxboards are commonly coated to enhance printability. This coating is generally composed of mineral pigments (85 to 90%) and polymer binders (10 to 12%). This study evaluated whether the presence of the coating layer allows the assembly of paperboards by US welding. Results indicated that welding coated folding boxboards is possible provided that coating weight and binder content are high enough. The mechanical performances of the welded boards met the requirements of most packaging applications. Adhesion in the welded joint resulted from a combination of thermoplastic (melting and flowing of the binder) and thermoset (degradation reactions) effects. However, it was not possible to assemble coated folding boxboards without degrading the welding zone. While the materials and process need to be optimized, this work represents a big step forward toward the adhesive-free assembling of paper-based materials.
Si Young Ha, Ji Young Jung, Dong Hwan Lee,
Published: 1 July 2021
Abstract:
Zanthoxylum schinifolium Sieb. et Zucc. (syn. Fagara schinifolia Engler) was studied for its potential anti-inflammatory properties. The hydrosol extract prepared from the Z. schinifolium branch was analyzed by gas chromatography/mass spectrometry. Here, five main chemical components were identified in the hydrosol of the branches of this shrub. The main chemical compounds in the branch inhibited both an Immunoglobulin E (IgE)-antigen complex and a dinitrophenyl-bovine serum albumin (DNP-BSA)-induced β-hexosaminidase release in a dose-dependent manner in RBL-2H3 mast cells, and at the tested concentrations did not show cytotoxicity to RBL-2H3 cells. Moreover, hydrosol obtained from the branch substantially inhibited a lipopolysaccharide (LPS) induced overproduction of intracellular active oxygen (ROS) and nitric oxide (NO). Consistently, the soluble N-ethylmaleimide-sensitive factor-attachment protein receptor (SNARE) proteins of SNAP23, syntaxin4, VAMP7, and VAMP8 were remarkably decreased through hydrosol treatment. Hydrosol suppressed the activation of SNARE proteins in DNP-BSA-stimulated RBL-2H3 cells and inhibited ROS and NO in LPS-stimulated RAW264.7 cells. Camphor and estragole are the main chemical components of hydrosol and downregulate the LPS-induced phosphorylation of the SNARE proteins. The hydrosol obtained from the branch of Z. schinifolium has therapeutic benefits for allergic inflammatory diseases.
Jinlan Dai, Honglei Yin, Lingyun Yu, Tang Hong, Lei Zhou, Minghua Liu
Published: 1 July 2021
Abstract:
Aniline derivates are widely used in rubber products as anti-aging agents, but their biological toxicity causes harm in the use and recycling of rubber products. Therefore, in this study, a high-performance poly(3,4,5,6-tetra-fluorophthalonitrile-β-cyclodextrin)(P-TFPN-β-CD) solid-phase extraction (SPE) adsorbent was synthesized and applied to extract and detect aniline derivatives in rubber specimens. After crosslinking with 3,4,5,6-tetrafluorophthalonitrile (TFPN), the polymer exhibited mesopores (7.88 nm) and a large specific area (55.2 m2/g). The porous structure significantly improved the extraction efficiency (recovery was between 90.1% and 110.5%) and rate (60% in 10 s) of 4 aniline derivatives (aniline, N-ethyl aniline, 1,2-phenylenediamine, and p-phenylenediamine). With a combined gas chromatographic-flame ionization detector (GC-FID), the extracted aniline derivatives were accurately detected (RSD = 1.60% to 9.90%). Due to the weak interaction between P-TFPN-β-CD and analyte, the prepared poly-TFPN-β-CD SPE adsorbent was regenerated via mild washing with methanol. The high absorption capacities remained after 4 extracting-washing cycles. The novel porous SPE adsorbent showed good extracting and recycling performance for the analysis and detection of aniline compounds in rubber. Thus, it has good prospects for application to improve detection efficiency and reduce cost.
Weihua Wei, Rui Cong, Tongming Xue, Ayodele Daniel Abraham, Changyong Yang
Published: 1 July 2021
Abstract:
Wood-plastic composites have attracted extensive attention throughout the world because of their advantages. However, the manufacturing mechanism of the wood-plastic composites, i.e., high-speed milling technology, is not perfect and needs further study. The effects of the cutting parameters, i.e., the spindle speed, feed rate, axial milling depth, and radial milling depth, on the surface roughness and chip morphology were studied; the surface roughness values, Ra and Rz of high-speed milling wood-plastic composites samples were measured via high precision surface roughness measuring instrument, and their regression equations were calculated. The chips produced via a high-speed milling process were collected and studied. The results showed that the surface roughness of the wood-plastic composites increases with an increase in the axial depth, feed rate, or radial depth, but decreases with an increase in the spindle speed. In addition, the axial milling depth, feed rate, and spindle speed had a significant effect on the morphology of the chips. However, the effect of the radial milling depth on the morphology of the chips was not obvious. The results can provide a scientific basis for the optimization of high-speed milling processing of wood-plastic composites.
Published: 1 July 2021
Abstract:
A multi-directional relationship may be conceivable between elements and melatonin in sessile organisms. Melatonin is an important hormone that helps regulate metabolism. This study investigated how different doses (0 μM/control, 250 μM, 500 μM, 1000 μM, and 1500 μM) of exogenous melatonin supplementations (EMS) affected the elemental contents in Anatolian black pine (Pinus nigra Arnold. ssp. pallasiana (Lamb.) Holmboe) seedling tissues (root, stem, and needle). Two different application forms (root-dipping and needle-spraying) were selected in the study. In the samples of seedling tissues, sodium (Na), potassium (K), calcium (Ca), iron (Fe), aluminum (Al), magnesium (Mg)/ppm; chrome (Cr), cobalt (Co), copper (Cu), manganese (Mn), nickel (Ni), phosphorus (P), selenium (Se), silicium (Si), silver (Ag), sulfur (S), zinc (Zn), and molybdenum (Mo)/ppb were analyzed using inductively coupled plasma optical emission spectroscopy (ICP-OES). Of the 18 elements examined, there was a statistically significant difference (p<0.05) between all seedling tissues and different doses of EMS. The results show that EMS may have the regulatory effect on seedling tissue element metabolism.
Na Young Park, Young Chan Ko, Hyoung Jin Kim, Byoung Geun Moon
Published: 25 June 2021
Abstract:
Surface properties include both surface roughness and friction. With a stylus-type contact method, it is necessary to obtain either a surface roughness profile or a friction profile that is affected by stylus shape and size, its contact force on the sample, the scan speed, and the data acquisition rate. As a new surface parameter, the mean absolute deviation (MAD) from an average property has been introduced. It represents the deviation from either the roughness average (Ra) and the average coefficient of friction (COF), respectively. While Ra or average COF depends on the instrument and its operating conditions, the MAD should not depend on them because it represents the variations within the sample.
S. L. McAlexander, S. M. Noble, K. McCance, M. R. Blanchard, R. A. Venditti
Published: 25 June 2021
Abstract:
Two survey instruments measuring undergraduate students’ beliefs about bioproducts/bioenergy and related careers were developed and validated in this research study. The Beliefs about Bioproducts/Bioenergy (BABB) and Career Interest in Bioproducts/Bioenergy (CIBB) surveys were administered to undergraduate students enrolled in courses in a natural resources college. BABB (N = 168) and CIBB (N = 203) survey results were analyzed using exploratory factor analysis (EFA) and confirmatory factor analysis (CFA). Validity and reliability were demonstrated. The BABB has two related scales, Personal (P) and Societal (S), which can be used together or separately. ANOVA and t-test analyses determined that students with majors closely related to bioproducts/bioenergy held significantly more positive personal and societal beliefs about bioproducts/bioenergy, as well as related career interests. Differences were identified based on gender, but not by race/ethnicity. Measuring student beliefs about bioproducts/bioenergy and interest in related careers may help to gauge trends and changes in beliefs that influence environmentally-related choices and support efforts to prepare a diverse workforce for the bioeconomy. The authors recommend the use of these surveys to measure the impacts of academic and professional development experiences.
Julia Montzerrat Gutiérrez-Acosta, Rocio Orihuela-Equihua, Luis Fernando Pintor-Ibarra, Nicolás González-Ortega, Juan José Hernández-Solís, Faustino Ruíz-Aquino, Manuel Alfonso Navarrete-García,
Published: 25 June 2021
Abstract:
The chemical composition of hardwoods sawdust and citrus residues from four states of the Mexican Republic (Quintana Roo, Durango, Veracruz, and Sonora) were determined. The results ranged as follows: total extractives from 8.2% (Quercus spp.) to 35.0% (lime leaves), holocellulose from 45.4% (lime leaves) to 70.6% (Lysiloma latisiliquum), lignin from 3.9% (lemon peels) at 25.4% (Caesalpinia platyloba), ash from 0.4% (orange branches) to 6.3% (lemon peels), pH from 5.1 (Swartzia cubensis) to 7.3 (orange branches), and calorific value of 19.8 MJ/kg (Lysiloma latisiliquum and Quercus spp.) to 21.7 MJ/kg (Olneya tesota). With the exception of the oak samples, in all the biomass samples the extractives content is relatively high (10.1% for Lysiloma latisiliquum to 35% for Persian lime leaves), and could represent a potential for future study and applications in the field of antioxidants. Due to the chemical properties and calorific value, the biomass samples studied present potential for local use as densified biofuels (pellets or briquettes).
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