NC State
  • Researchpp 6325-6340Gao, Y., Hu, X., Tong, S., Kan, J., Wang, Y., and Kang, F. (2022). "Multi-objective optimization of peak cutting force and cutting energy consumption in cutting of Caragana korshinskii branches," BioResources 17(4), 6325-6340.AbstractArticlePDF

    Caragana korshinskii (C.K.) flat stubble residue is an abundant biomass energy source in China. Because branch cutting is closely related to the harvesting of forest biomass, it is practical for forestry production and ecological development to investigate the effects of cutting parameters on the peak cutting force and cutting energy consumption of C.K. branches. In this study, the effect of cutting parameters on the peak cutting force and cutting power consumption of branches was investigated by single-factor and multi-factor tests using an independently developed reciprocating cutting test bench, and an optimization model was established. The interaction term of average cutting speed and tool cutting edge inclination angle significantly affected the peak cutting force, while the interaction term of cutting clearance and wedge angle had a significant effect on the cutting energy consumption. The optimal combination of cutting parameters was an average cutting speed of 0.5 m/s, cutting clearance of 1.4 mm, wedge angle of 25°, and tool cutting edge inclination angle of 20°. With this combination of parameters, the corresponding peak cutting force was 644.38 N, and the cutting energy consumption was 5.90 J, which was less than 5% relative error between each performance index and the theoretical optimized value.

  • Reviewpp ###-###Shi, D., Hu, X., Hong, W., Zhang, J., and Du, H. (2022). "Review of connections for timber-concrete composite structures under fire," BioResources 17(4), Page numbers to be added.AbstractArticlePDF

    A timber-concrete composite structure has the advantages of energy saving, environmental protection, and low carbon, and has wide application prospects. However, the effects of fire on timber-concrete composite structures are complicated. It is important to study the fire performance of connections and their influencing factors for the promotion and application of timber-concrete composite structures. This paper summarizes the research progress of connections for timber-concrete composite structures under fire. Firstly, research on the performance of connections in timber-concrete composite structures under fire is introduced, including screwed connections, notched, and grooved connections, and steel truss plate connections. Secondly, the calculation methods focused on connections of timber-concrete composite structures under fire are introduced. Finally, the main points of modeling timber-concrete composite structures under fire are also briefly introduced.

  • Researchpp 6341-6357Feng, C., Zhou, J., Xu, X., Jiang, Y., Shi, H., and Zhao, G. (2022). "Three-dimensional bioprinting and electrospinning of cellulose nanocrystal/polycaprolactone for tracheal scaffolds," BioResources 17(4), 6341-6357.AbstractArticlePDF

    Three-dimensional printing (3DP) has high flexibility and controllability, and has attracted extensive attention in the biomedical field. However, the scaffolds prepared only by 3D bioprinting have poor mechanical properties, and they cannot effectively carry the required drugs. At the same time, compared with the size of cells, the pore size of 3D printed scaffolds is relatively large, and the efficiency of cell inoculation and tissue formation are still limited by the pore resolution of scaffolds. Therefore, a new method of forming 3D printing trachea composites is proposed. When combined, 3D bioprinting and electrospinning (ESP) can overcome the issues associated with scaffolds prepared by 3D bioprinting alone. Nanofibers create a suitable environment for cell growth. In terms of material use, Polycaprolactone (PCL) is commonly used as an ideal material source for 3D printing, but its biomechanical properties are insufficient. Cellulose nanocrystals (CNC) can effectively improve the properties of polymers such as PCL. Therefore, the inner layer of the scaffold used in tracheal surgery is created from PCL/CNC composite by 3D bioprinting, and the outer nano-cellulose film is deposited on the inner surface by electrospinning. Mechanical properties and cell adhesion/growth of scaffolds prepared by 3D bioprinting combined with electrospinning were found to be superior to those of scaffolds prepared by 3D bioprinting.

  • Researchpp 6358-6376Aytin, A., and Çakıcıer, N. (2022). "Weathering’s effect on color and roughness in some heat-treated wood species with modified water-based varnish," BioResources 17(4), 6358-6376.AbstractArticlePDF

    Heat treatment in wood materials and the use of water-based varnishes (WBV) in furniture made from heat-treated wood materials come to the fore in terms of supporting environmentally friendly production in the wood sector. In this study, the total color changes (ΔΕ*) and surface roughness (SR) were investigated after heat-treated tree species were exposed to natural and accelerated weathering with and without varnish. In this context, test samples were first divided into two groups. Surface treatment was applied to the samples in the first group by applying modified WBV (A1) and normal WBV (A2), and the second group was left unvarnished. Then, one group of the varnished samples was subjected to natural weathering (NAT) for 90 days and the other group was subjected to accelerated weathering (QUV) for 720 h with VAS samples, and then the ΔΕ* and SR values of the samples were calculated. The results revealed that ΔΕ* was the lowest in the QUV WBV group, and NAT was more effective than QUV in ΔΕ*. The highest SR values among all groups were measured in the VAS group, and among the varnished samples, there was no statistical difference between A1 and A2 in SR values, except for Rq.

  • Researchpp 6377-6396Yi, W., Feng, F., Yuan, X., Hao, J., Guo, Y., and Lu, B. (2022). "Transcriptome analysis reveals the molecular patterns regulating prickle reduction in grafted Zanthoxylum armatum," BioResources 17(4), 6377-6396.AbstractArticlePDF

    Grafting has been found to effectively reduce the prickly nature of Zanthoxylum armatum seedlings, but the molecular mechanisms are unclear. A comparative transcriptome analysis was performed on stems (JJ) and leaves (JY) of grafted stems (SJ) and leaves (SY) of non-grafted Zanthoxylum armatum seedlings. The authors obtained 3097, 2124, 5995, and 5043 differentially expressed genes from JJ vs. SJ, JY vs. SY, JY vs. JJ, and SY vs. SJ with 17 co-expressed genes. The RNA-seq results were confirmed by qRT-PCR analysis. Function annotations showed that many DEGs enriched plant hormone signal transduction, phenylpropanoid biosynthesis, and plant-pathogen interaction. Secondary metabolites associated with stress-related hormones and defense were noticeably up-regulated in grafted plants. However, key enzymes regulating lignin synthesis were slightly down-regulated in grafted plants. Additionally, grafted plants had several noticeable up-regulated stress-response TFs (transcription factors), including NAC (NAM, ATAF1/2, CUC1/2), ERF (ethylene response factor), MYB (v-myb avian myeloblastosis viral oncogene homolog), bHLH (basic helix-loop-helix), and WRKY. This study generated abundant sequences for elucidating the genetic differences between grafted and non-grafted Z. armatum.

  • Researchpp 6397-6410Shi, D., Hu, X., Zhang, J., and Du, H. (2022). "Shear stiffness of notched connectors in glue laminated timber-concrete composite beams under fire conditions," BioResources 17(4), 6397-6410.AbstractArticlePDF

    Shear connectors ensure effective interaction between wood beams and concrete slabs of composite beams, and their properties noticeably affect the fire resistance of timber-concrete composite beams. To investigate the shear stiffness of notched connectors in glued laminated timber (GLT)-concrete composite beams under fire conditions, 16 shear tests were conducted. The effects of fire duration and notch length on shear properties of the connectors for a given spacing were studied. The fire tests indicated that the reduction of the notch length from 200 mm to 150 mm remarkably affected the failure mode of the shear specimens, changing from compression failure of notched wood to shear failure of notched concrete. The increase in fire duration reduced effective width of the notched wood, negatively affected the shear stiffness and shear capacity of the connectors, and the shear stiffness decreased more rapidly. The notch length did not have a substantial effect on the shear stiffness of connectors. Based on the experimental results, an analytical model to estimate the shear stiffness of notched connectors in GLT-concrete beam under fire conditions was established.

  • Researchpp 6411-6444Yue, X., Li, Z., Lam, S., Peng, W., and He, Y. (2022). "Reuse of Cornus officinalis nutlet for bioenergy," BioResources 17(4), 6411-6444.AbstractArticlePDF

    As a traditional nourishing Chinese herbal medicine, Cornus officinalis Sieb. et Zucc. has a long history of application. At present, only the flesh of the fruit of Cornus officinalis is used as a medicine, which wastes a large quantity of ingredients in the nutlet. To improve the comprehensive utilization efficiency of the fruit’s nutlet, which could be used when there is a shortage of the plant’s fruit in the market, this study used Fourier transform-infrared spectroscopy (FT-IR), gas chromatography-mass spectrometry (GC-MS), thermogravimetric (TG) analysis, pyrolysis-gas chromatography-mass spectrometry (PY-GC-MS), and nuclear magnetic resonance (NMR) techniques to analyze the Cornus officinalis nutlet. The results showed that the active ingredients of Cornus officinalis nutlet have great medicinal value and could become a substitute for the fruit. After extracting the active ingredients, the residue can be used as a good biomass liquid fuel, providing reference for the future to replace fossil fuels. This study provides the scientific basis for the comprehensive utilization of high-quality resources for Cornus officinalis.

  • Researchpp 6445-6463Olarescu, A. M., Lunguleasa, A., and Radulescu, L. (2022). "Using deciduous branch wood and conifer spindle wood to manufacture panels with transverse structure," BioResources 17(4), 6445-6463.AbstractArticlePDF

    The increasing demand on the wood market makes it necessary to use all secondary resources, including the wood branches and spindles. The properties of deciduous branches and softwood spindles were evaluated in order to create wood panels, highlighting the transverse texture with high value added. The research analyzed the properties of the wood from deciduous (beech, maple) branches and from conifer (spruce, fir) spindles. The methodology of obtaining panels with transversal structure was also presented. The production of minor wood (branches or spindles) was 254 m3/ha/year in the case of beech (branches) and 109 m3/ha/year in the case of spruce (spindles). The proportion of compression wood for spruce had an average value of 40.6%. A similar value of tension wood for beech was obtained. The modulus of elasticity for pine spindle wood was 71.7% lower than the modulus of elasticity for bending strength in the trunk. The quality index was 36.7% lower in the case of spindles than in the case of pine trunk, and the value of the quality ratio in branch maple wood was 2.61% lower than in trunk wood. Thus, even if it is not the only efficient solution, wood in the minor portions can be used to make high value-added panels such as those that highlight the transverse structure.