Volume 17 Issue 1

Carbon fiber (CF)-filled fiberboard specimens for electromagnetic (EM) shielding applications were produced in this study by mixing CF with wood fiber (WF). The aim of this work was to study the panel properties with different loadings (1%, 2%, 3%, 5%, and 10%) of CF. The mechanical, physical, and electromagnetic interference (EMI) shielding properties of the produced medium density fiberboard (MDF) were analyzed. The shielding effectiveness (SE) of the CF1 sample was 23.5 dB to 35.0 dB in the frequency range of 8.2 GHz to 12.4 GHz. The maximum SE of 64 GHz to 76 dB was obtained for the CF10 sample. The investigation of the mechanical properties of MDF panel indicated that the modulus of rupture (MOR), modulus of elasticity (MOE), and internal bonding (IB) of the composite panels were less than those of the control panel. The MOR, MOE, IB, thickness swelling (TS), and water absorption (WA) of the panel with 1% CF (CF1) were 24.7 MPa, 2,510 MPa, 0.69 MPa, 14.5%, and 52.3% respectively. Generally, the MDF panels with 1% CF exhibited a greater ability for EM shielding applications because of their acceptable properties according to the EN 622-5 (2019) standard and appropriate EM shielding of at least 20 dB.

Laccase has huge potential application in all aspects of biotechnology due to the ability of laccase to oxidize a wide range of phenolic and non-phenolic compounds. The future success of such applications requires large amounts of laccase with low costs. White-rot fungi are important groups of laccase production. In this study, three white-rot fungi, Phlebia acerina Han 618, Trametes hirsuta Han 726, and Coriolopsis trogii Han 751, isolated from a native North China habitat, were identified by the method of molecular biology and preliminary screening of the ability of laccase-production by guaiacol selection medium. Then they were fermented on different lignocellulosic biomass. Three species showed consistency in preference of lignocellulosic biomass, and the presence of stalk of Sorghum bicolor was more suitable for secreting laccase. The capacity of laccase secretion from different species was significantly different. The capacity of secreting laccase of C. trogii Han 751 was superior to that of P. acerina Han 618 and T. hirsuta Han 726. The discovery of a new strain with superior capacity of secreting laccase and suitable lignocellulosic biomass were helpful for laying a foundation for the optimization of the fermentation conditions for the highest laccase production, the isolation and purification of laccase, and the industrial application of laccase.

Consumer preferences were examined with respect to the decision-making process to purchase home and office furniture in Iran. A conceptual model was proposed based on the theoretical framework from literature. The data was obtained from interviews with customers who were buying wooden furniture. The main data collection tool in this study was a questionnaire. The results were processed using structural equation modelling (SEM) in SmartPLS software. SEM is a multivariate method that combines multiple regression and factor analysis aspects. PLS-SEM has been increasingly developed in various fields in recent years, due to its usability in nonnormal data, small sample sizes, and the use of formative indicators. The findings revealed a significant relationship between all research factors and consumer preferences of home and office furniture, although the model quality assessment showed that safety and environment (0.576=strong effect), salesperson’s characteristics (0.197=medium effect), corporate responsibility factors (0.058=weak effect), internal factors (0.029=weak effect), and product characteristic (0.023=weak effect) had the highest impact. These independent variables accounted for 93.8% of the changes of the dependent variable of consumer preferences.

A high yield cellulase production strain was screened from the surface of cigar wrapper leaves and added to cigar wrapper leaves for fermentation in the present study. The enzyme-producing strain was identified as Bacillus velezensis, and its maximum carboxymethyl cellulase activity could reach 44.3 U/mL. Making the cellulose degradation rate of cigar wrapper leaves as the index, the fermentation temperature, inoculum concentration, and carbon and nitrogen source addition concentration were optimized by response surface methodology. The results showed that under the conditions of inoculation concentration of 20%, fermentation temperature of 37 °C, addition of 4.5 ‰ glucose and 2.25 ‰ glutamate, the highest degradation rate of tobacco cellulose was 31.7%. Significance analysis results showed that the order of factors affecting the degradation rate of cigar wrapper cellulose was: inoculation concentration > carbon and nitrogen source addition concentration > temperature. The analysis of aroma substances under the optimal conditions found that the total amount of aroma substances of cigar wrapper increased by 26.1% compared with that before fermentation, in which β-damascenone, megastigmatrienone, farnesyl acetone, and solanone were significantly improved. The results were conducive to improving the aroma quality and concentration of cigar wrapper leaves.

The pH is one of the key factors affecting microbial activity in anaerobic systems. In this paper, the pH impact tolerance of Fe0/GO (zero-valent iron/graphene oxide) mediated anaerobic treatment system for high concentration organic wastewater was studied. The effects of a Fe0/GO mediated anaerobic system on wastewater treatment, degradation kinetics, and the physicochemical properties of sludge were studied at pHs of 5.5 and 8.5; the separate addition of Fe0 and GO and a blank system were used as the blank control. The results showed that the pH had adverse effects on the treatment of each system and the physicochemical characteristics of sludge. However, the Fe0/GO system under pH shock maintained a relatively high CODCr removal rate and gas production; the effluent volatile fatty acid content was the lowest, the effluent pH value deviation from the normal range was small, the degradation rate constant, and sludge concentration and flocculation performance of the mixed liquid were better than those of other systems. The recovery phase of Fe0/GO returned to normal in a relatively short time. These results showed that adding Fe0/GO to the anaerobic treatment of high concentration organic wastewater system can drastically improve the pH shock resistance of the system.

A densification method is proposed and developed to improve the mechanical properties of Uludağ fir (Abies bornmüelleriana Mattf.) and black poplar (Populus nigra L.) woods. The method, called Thermo-Vibro-Mechanic® densification, is derived from the hypothesis that the vibration added to the traditional thermo-mechanical densification process can cause the wood cell walls to interlock with each other at the micro-level via the friction effect. In addition, it aims to remove the cell cavities under lower pressure compared to other densification methods via the shaking effect. To test this hypothesis, the samples, obtained in both the radial and tangential directions, were pre-treated with wood stain and preservative before undergoing the densification process. Thermo-Vibro-Mechanic® densification was performed at varying temperatures (100, 120, and 140 °C), pressures (0.60, 1.00, and 1.40 MPa), and durations (20, 60, and 100 s). The changes in the values of the bending strength, modulus of elasticity, and compression strength parallel to the grain in the radial and tangential directions were determined accordingly. The results showed that the Thermo-Vibro-Mechanic® densification process increased the bending strength and modulus of elasticity values up to 50%, while the compression strength reached 67% higher than the untreated wood.

In recent years, people’s acceptance of online shopping has increased markedly with the gradual maturing of e-commerce. The furniture industry in China, along with many other countries, is paying increased attention to the online retail business. The furniture online consumption experience has attracted attention both in academic and industrial fields. The purpose of this paper is to provide a literature review of the furniture online consumption with an aim to extend the concept of consumer experience to the context of online furniture consumption. The paper offers three important contributions for both academics and practitioners. First, it analyzes the main influencing factors of the consumer experience concerning wood furniture online consumption in China. And secondly, it proposes a conceptual framework of furniture online consumer experience (FOCE), which divides online consumption experience into three dimensions: perceived risk experience, emotional experience, and new technology interactive experience. Finally, from a managerial perspective, the authors put forward constructive strategies in terms of furniture online sales. The findings of this study afford practical implications for the improvement of the online shopping experience of consumers for furniture companies.

The pretreatment of 7- and 10-year-old Acacia mangium wood using incision, forced-air dying, and pressure were conducted to evaluate the effects on wet pockets, the drying rate, and drying defects. Quarter and rift sawn boards were used in this study. Results showed that the incidence of wet pockets in the incised, forced-air drying, and pressure-treated quarter and rift sawn boards of 7-year-old A. mangium alleviated up to 35% and 79%, 60% and 54%, and 54% and 82%, respectively. In 10-year-old A. mangium, the occurrence of wet pockets was reduced by 68% and 60%, 31% and 73% and 82% and 73% in quarter and rift sawn boards, respectively. Drying rates of 7-year-old A. mangium pressure-treated boards increased by 5% and 40% in quarter and rift sawn boards, respectively. The drying rate was 10% faster for 10-year-old A. mangium pressure-treated boards. The application of the pressure pretreatment yielded no severe drying defects at the end of the drying period, except for a mild collapse in one of the 10-years old A. mangium sample boards. Incision and forced-air drying pretreatments improved the drying rate; however, pressure treatment was found to be superior in reducing wet pockets and drying defects.

Wild pear plant species Pyrus spinosa Forsk., naturally grown in woodlands in Turkey, are one of the most important wild fruits consumed by local people as food, as well as used for medical purposes. In this study, some chemical properties were determined such as fruit seed and fruit pulp antioxidant and antimicrobial activities, fruit seed fatty acid components of Pyrus spinosa determined, which grow naturally in Ödemiş, İzmir, in the south of Turkey. The qualitative and quantitative analyses of fatty acid components of fruit seed of P. spinosa were determined by GC/MS analysis. A total of 16 fatty acids in the fruit seed were found in the analysis results and 44.8% linoleic acid (C18:2n6c), 40.5% oleic acid (C18:1n9c), and 7.6% palmitic acid (C16:0) components were found in higher proportions. Free radical removal effects of fruit seed and fruit pulp extracts were determined using the DPPH method. The antimicrobial activity of fruit pulp extract of P. spinosa was determined by the disk diffusion method against E. coli, S. aureus, and C. albicans. This study revealed that the fruit pulp and fruit seed of P. spinosa, which had a significant level of antioxidant activity, antimicrobial activity, and fruit seed had high levels fatty acids components.

The frequency (or pitch) content of bamboo angklung musical instruments was analyzed. The pitch of the rattle tubes was determined via a Pico oscilloscope recording both the time and frequency spectrum. Fast Fourier transform analysis identified the fundamentals and overtones of the individual tubes, which were compared with the calculated theoretical resonance frequency. The pitch, due to the coupling effects of two rattle tubes, slightly varied from the pitch of the individual rattle tubes. Although both rattle tubes (played simultaneously) displayed the fundamental frequencies in both tubes, the individual tubes played separately did not produce the exact frequency obtained from both tubes played simultaneously. The spectrum of both tubes produced sound output from the individual tube, which is shown by two prominent peaks, corresponding to the pitch of the individual tube. Although the long and short tube show an individual fundamental frequency of 528 Hz and 1095 Hz, respectively, for C5 tube (when played separately), the coupling of both tubes produced the first and second peaks (when played simultaneously) at 546 Hz and 1093 Hz. Due to the disparity of the fundamental frequency, the inner diameter and length of the tube was utilized for the theoretical resonance frequency calculation.