Volume 19 Issue 1

The global climate warming caused by greenhouse gases poses a great threat to human living and biological ecosystems. To mitigate climate change, many measures have been taken to reduce carbon dioxide emissions. Among them, the forest carbon sink (FCS) is considered as one of the most economical and effective carbon sequestration methods to realize carbon emission reductions in next 30 to 50 years. FCS projects are being implemented in many countries to increase their carbon sequestration and thereby to realize carbon emission reductions. However, there are some issues associated with implementation with such policies. Firstly, these projects mainly have focused only on carbon sequestration and have ignored the comprehensive ecological effects to obtain their best economical benefits. Secondly, implementing these projects fails to establish a sustainable and healthy forest industry because they place too much reliance on preferential policies from governments. Finally, the projects lack systematic technological standards and legislation to guarantee their smooth implementation. This editorial briefly discusses these issues for the suitable implementation of the FCS projects.

This editorial presents insights into sustainable and intelligent manufacturing in line with the 2030 agenda for sustainable development. It begins by framing the concept of sustainable development and its objectives within the scope of the 2030 agenda. Then it explains the concept of sustainable and intelligent manufacturing in agreement with the latest developments in the industry. It finishes by envisioning the integration of Industry 5.0 in the 2030 agenda.

This editorial envisions a future in which greater value is obtained from technical lignins. The currently available amounts of such lignins are immense, and the costs are often in line with lignin’s fuel value. Key challenges are associated with lignin’s complexity. When envisioning future prospects for lignin, it is important to consider any differences between different types of technical lignin as a starting material.

Waterlogged archaeological wood of shipwrecks has been preserved under seawater for centuries, such that microbial erosion has caused severe bacterial degradation and acidification. These wooden cultural relics are of great significance for understanding the shipbuilding technology, trade activities, and environmental ecology of centuries ago. From the perspective of structure and composition, these waterlogged archeological woods have the characteristics of high water content and a large loss of lignin and cellulose, which makes the hull prone to collapse during preservation. Therefore, it is urgent to apply conservation and preservation treatments for deacidification and consolidation. Due to the fragility of wood and the complexity of repair work, the current development of conservation and preservation technology has multiple aims, such as antibacterial, deacidification, and reinforcement effects. In this editorial, the current challenges and conservation treatments with antimicrobial or deacidification utilities will be introduced.

Even though the recycling of paper and paperboard is quite successful when compared to the recycling of other resources, there are many things to improve. Recovering the used paper and paperboard without contamination and sending it back to the papermill that produced it would enhance the recycling potential and efficiency of recovered fiber resources. Close collaboration between a paper and packaging company and a logistics company has made a big improvement in recycling and achieved the circular economy of fiber resources. It is time to find better ways to collaborate, thereby improving our capability to keep our planet green.

As a way to reduce carbon emissions, manufacturing an environmentally friendly and biodegradable cellulose aerogel material with low thermal conductivity, excellent mechanical, and flame retarding property to replace conventional foams is of significant interest in thermally insulating building applications. Primary questions to be addressed include how to design fire retarding and mechanically robust wood derived cellulose nanofibril aerogels as alternatives of expanded polystyrene and rigid polyurethane foams; how to develop aerogel materials in industrial-level manufacturing; and whether it is possible to further develop its early fire alarm sensors with ultra-low temperature sensitive limit and long signal durability by experimental and machine learning artificial intelligence approaches for thermally insulating sustainable building applications.

Terminology plays a crucial role in shaping our understanding of a field. In this editorial, we focus on the widely used terms “wet end” and “wet end chemistry” within the realm of papermaking. By delving into historical records, our aim is to provide a deeper understanding and a clearer perspective on these terms. It is worth noting that exploring terminology can enhance comprehension and foster a more comprehensive understanding of the subject matter.

The economic feasibility of producing structural-grade hardwood lumber (SGHL) that qualifies as a raw material for structurally rated cross-laminated timber (CLT) was examined. 126 yellow poplar logs from diameters 12 to 15 inches were selected and divided into test and control samples. A log yield study was then conducted of the yield and revenue generated when producing lumber graded with National Hardwood Lumber Association (NHLA) rules, SGHL rules, and a mix of both rules (NHLA and SGHL-graded lumber). Producing mix-grade lumber added approximately 27% more revenue than producing NHLA-grade lumber on average if sawmills adopt a cant sawing method. Mix-grade lumber production resulted in 32% of the total volume produced as SGHL and the remaining 68% as NHLA lumber. As a result, 2 Common and lower-grade lumber board footage was reduced to only 29% in test samples and remained converted into SGHL compared to more than 85% of 2 Common and lower-grade lumber boards for control samples. 95% of the SGHL produced as mixed-graded lumber with NHLA-grade lumber met the specifications required to produce structural CLT, and the remaining 5% can be utilized to produce non-structural grade CLTs if they meet the minimum requirement of the materials for CLT production.

Bamboo fiber was extracted after alkaline treatment, and the mechanical properties of fibers and polymer composites were measured. The results showed that the strength of bamboo fiber was higher when the diameter was smaller. Smaller diameter bamboo fibers were dense, while larger diameter ones were composed of vascular bundles, which contained inside voids and outside parts having insufficient lignification. Tensile tests were conducted on bamboo fibers after heating at constant temperatures, and a significant decrease in mechanical properties was observed at heating temperatures above 250 °C. Bamboo fibers were compounded with PE, PA12, ABS, PA6, and biobased PC (Durabio), and injection-molded to prepare the composite specimens for flexural testing. The composite of polyethylene with 30 wt% bamboo exhibited considerably high flexural modulus compared to pure PE. Nevertheless, a large plastic deformation, which was equivalent to that of pure PE was observed. In other polymer composites, those flexural moduli increased, and degree of plastic deformation decreased dramatically, leading to brittleness. For PA6, which was molded above 250 °C, the increment in flexural modulus by fibers was less than the other composites due to the thermal decomposition of the fibers.

To simulate the creep characteristics of corn straw particles under uniaxial compression, a 6-level 2D model was created using PFC 2D software according to the actual uniaxial creep test, the grain size, and shape of corn straw particles. Five groups of controlled tests were designed by the control variable method to study the influence of Maxwell body parameters E_m, η_m; Kelvin body parameters E_k, η_k; and friction coefficient f on the creep curve of Burgers model. Results revealed that the creep characteristics of corn straw are affected by these 5 parameters. After multiple debugging by trial-and-error method, simulation parameters suitable for describing the creep characteristics of corn straw particles were obtained. The creep curves obtained by simulation under these parameters are consistent with those obtained by physical tests. It was shown that PFC software can not only study the creep characteristics of geotechnical materials, but also study the creep characteristics of agricultural fiber materials, which provides a reference for the subsequent rheological characteristics of biomass materials.