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As an environmentally friendly and sustainable nanoparticle stabilizer of Pickering emulsions, cellulose nanocrystal (CNC) has attracted attention because of its sustainable and biodegradable characteristics. Despite its distinct amphiphilic character as an ideal nanomaterial to replace traditionally non-sustainable surfactant emulsifiers, its long-term stability and lack of responses from external stimuli [e.g., pH, temperature, and carbon dioxide (CO2)] are the critical issues to be addressed. The solutions for all of these questions in terms of CNCs and its responsive Pickering emulsions are systemically discussed in this review.

In view of a need for high-performing materials, while also minimizing contributions to plastic pollution, especially ocean micro- or nano- plastic pollution, biodegradable hydroxypropyl cellulose (HPC) and nanocellulose (CNC) liquid crystal biopolymers have attracted attention as emerging fields. Their structures, phase behaviors, and advanced characterization techniques in terms of synchrotron X-ray and neutron small angle scattering of HPC solutions and CNC suspensions have been systemically studied. Diverse left- and right-hand chiral liquid crystal HPC and CNC photonic elastomer materials are further explored. To achieve their complex structure design and mass-scale manufacturing, soft matter photonic materials via advanced manufacturing techniques are critically considered in this review. The goal is to enable their applications in intelligent coating, photonic fiber, and intelligent packaging.

Abstract Electroluminescent (EL) devices are of great significance for expanding the application range of optoelectronics. However, the realization of EL devices with environment-tolerance, stretchability, mechanical cycling stability, self-adhesion, biocompatibility, and high dielectric constant still remains a challenge. Herein, a type of EL device with enhanced comprehensive performances composing of a chlorinated barium titanate/phosphor/polydimethylsiloxane (Cl-BT/phosphor/PDMS) luminescent layer sandwiched between two silver nanowire-cellulose nanocrystal with II crystalline allomorph/Triton X-100 modified polydimethylsiloxane (AgNW-CNC II/TX-PDMS) electrodes fabricated through a full solution-processing strategy is proposed. Environmentally-friendly CNC II with high transmittance acts as an antioxidant, dispersant and film-former for AgNWs. The hydrophilic modification of TX to PDMS imparts the electrodes with self-adhesion, high stretchability, as well as strong interfacial bonding between TX-PDMS and AgNW-CNC II. The electrodes achieve skin-like modulus by adjusting TX content, endowing the EL devices with a high compliance (186 kPa of Young’s modulus). The luminescent layer with Cl-BT exhibits a high dielectric constant (19) and luminance (up to 72 cd m−2). The assembled EL device with excellent cyclic stability (luminance retention 85% after 400 cycles), durability (luminance retention >94% after 400 min) and stretchability (88% luminance at 200% strain) can work properly at broad temperatures (−20 ~ 70 °C) and underwater. This biocompatible and self-adhesive EL device demonstrates great potential for implantable biomedical devices and wearable displays under harsh environments.

In karst desertification (KD) regions, surface water (SW) easily enters underground through pore fissures and sinkholes despite the presence of abundant precipitation. Such regions have a typical distribution of “soil above and water below”, and, thus, the unique “karst drought” occurs. Hence, an urgent and primary problem in combating KD is to reach highly efficient utilization of water resources in these regions. We selected three karst research areas with different levels of karst desertification and different geomorphic types. By monitoring the storage and transformation of five types of water in the agroforestry system—precipitation, SW, groundwater (GW), soil water (SoW), plant water (PW), the following results were obtained: (1) In KD regions, a positive correlation was found among available precipitation, rainfall, and land evapotranspiration (LE), and LE was approximately equivalent to soil evaporation. (2) To varying degrees, agroforestry brings ecological benefits, including reducing surface runoff, increasing soil infiltration, lowering the transpiration rate, and reducing soil evaporation, thus achieving efficient use of water resources. (3) From 100 % rainfall, the transformation rates of SW, GW, PW, and SoW reached 0.14–12.71 %, 9.43–30.20 %, 9.79–49.97 %, and 40.72–82.58 %, respectively, and SoW showed a larger reserve than the other three types. (4) Drought stress contributes to the improvement of water use efficiency (WUE). Affected by drought stress, WUE was found to be the highest in a medium-intensity karst desertification environment. The transformation mechanisms of the five types of water observed in the agroforestry system provide a reference for efficient utilization of water resources in KD regions as well as theoretical support for addressing karst drought. They are also essential in helping to advance the ecological derivative industry, boosting the economy in karst mountainous areas, and controlling karst desertification.

This study investigated the tensile behaviors of hemp fiber bundles and examined how properties including tensile strength and Young’s modulus vary with the bundle diameter. Hemp fibers were extracted, degummed, and separated into bundles of different diameters ranging from less than 50 μm to over 150 μm. Tensile tests were conducted on these fiber bundles using a rheometer-based tensile testing machine. The results showed that hemp fibers exhibited a tensile strength of 97.33 MPa and a Young’s modulus of 3.77 GPa at a 50% survival probability. However, the scale parameters for breaking stress and Young’s modulus were determined to be 620.57 MPa and 29.88 GPa, respectively. As the fiber bundle diameter increased, the tensile strength decreased significantly. This was attributed to the higher probability of defects and irregularities acting as weakness points in larger fiber bundles. In contrast, Young’s modulus (stiffness) increased with increasing bundle diameter, likely due to improved fiber–fiber interactions. To further understand the variability and reliability of the tensile properties, statistical models were developed. The Weibull distribution analysis was applied, revealing critical insights into the variability of diameter, stress at break, Young’s modulus, and strain at break. The Weibull parameters provided a comprehensive understanding of the fibers’ mechanical reliability. Additionally, the Griffith model was employed to predict the strength and Young’s modulus based on fiber diameters, supporting the observation that thinner fibers generally exhibited higher tensile strength due to fewer defects. Overall, this work highlights the importance of understanding structure–property relationships in natural fibers like hemp for optimizing their performance in composites.

BackgroundThe causal associations between dietary intake and the risk and severity of Inflammatory Arthritis (IA) are currently unknown.ObjectiveIn this study, we aimed to investigate the causal relationship between nine dietary categories (30 types of diet) and IA using Mendelian randomization (MR).MethodsWe analyzed data from 30 diets and IA in a genome-wide association study (GWAS). Single nucleotide polymorphisms (SNPs) that could influence the results of MR analyses were screened out through the Mendelian Randomization Pleiotropy RESidual Sum and Outlier (MR-PRESSO) test. SNPs were analyzed through two-sample bidirectional MR using inverse variance weighting, MR-Egger regression, and weighted median method. The multiplicity and heterogeneity of SNPs were assessed using MR-Egger intercept term tests and Cochran’s Q tests. FDR correction was used to correct the p-values.ResultsIVW results showed that Beef intake [Odds ratio (OR) = 2.862; 95% confidence interval (CI), 1.360–6.021, p = 0.006, p_fdr 0.05) was positively associated with psoriatic arthritis (PsA); Cheese intake (OR = 0.579; 95% CI, 0.367–0.914, p = 0.019, p_fdr > 0.05) was negatively associated with PsA; both were suggestive evidence. Processed meat intake (OR = 0.238; 95% CI, 0.100–0.565, p = 0.001, p_fdr 0.05) and no directional pleiotropy was detected. Leave-one-out analyses demonstrated the robustness of the causal relationship in the positive results.ConclusionOur study presents genetic evidence supporting a causal relationship between diet and an increased risk of IA. It also identifies a causal relationship between various dietary modalities and different types of IA. These findings have significant implications for the prevention and management of IA through dietary modifications.

To enhance the nitrogen utilization efficiency of fertilizers, we developed a novel slow-release fertilizer hydrogel through free radical polymerization, incorporating lignin-containing cellulose nanofiber (LCNF), clinoptilolite (CL), urea, and acrylic acid (AA)-co-acrylamide (AAm) polymer. Various analytical techniques were utilized to examine the structure, swelling, and release behaviors of the fabricated hydrogels with varying LCNF concentrations. The results indicated that the addition of 10% LCNF led to a decrease in water absorption from 72.44 g g−1 to 24.04 g g−1. However, re-swelling was significantly enhanced, with a reduction in re-swelling capacity loss from 32.91% to 23.52%. Concurrently, water retention capacity notably increased from 18.03% to 39.20%. The hydrogel containing 10% LCNF exhibited a slower urea release over 30 days. The kinetic studies revealed that the swelling and urea release behaviors align well with the second-order kinetics model and the Peppas-Sahlin model, respectively. In summary, the developed LCNF/CL/(AA-co-AAm)/urea hydrogel nanocomposites present a novel strategy for the future production and utilization of slow-release fertilizers in agricultural and horticultural fields.

The special ''dual'' hydrogeological structure in karst areas causes rainfall easily ''leaking'' into the ground, resulting a unique ''karst drought''. In these areas, drought and insufficient water resources seriously restrict the sustainable development of agriculture. In order to restore the ecology of karst desertification, develop ecological industries, improve the utilization efficiency of water resources, and advance water-saving agriculture in such areas, literature review method was applied to discuss the suitability of agronomic water-saving measures in karst areas. The results are as follows. (1) Agronomic water-saving measures including tillage, mulching, water-fertilizer coupling, chemical regulation, crop allocation and deficit irrigation can all enhance the crop WUE. For example, deep tillage and deep loosening increased the WUE by 15.1 % and 15.9 % respectively. The WUE of spring wheat under straw mulching increased by 17.17 %–43.01 % compared with that under mulching film. Increased density of intercropping corn and wheat saved 9.85 % of water. (2) The cultural or natural particularity of karst areas limits the application of all agronomic water-saving measures in karst areas, and therefore choices and adjustments are necessary according to local conditions: ① No tillage should be adopted because of the high output of labor force; ② straw mulching need to be crushed; ③ the coupling of water and fertilizer reaches better effect when applied to crops several hours before rainfall; ④ the shallow soil layer and the complexity of preparing water retaining agent make it unsuitable to use water retaining agent; ⑤ agroforestry with dwarf and dense planting is more suitable; ⑥ crop deficit irrigation can be carried out by using ecological small pools. Based on the above results, proposes are offered in the following. First, it is necessary to construct the optimal model of regional water and fertilizer coupling in karst areas, and apply composite agronomic water-saving measures. Second, it is suggested to establish a model of coordinating forest, grain and grass, and vigorously develop ecologically derivative agroforestry. Third, there is a necessity to strengthen the research and development of technology about soil and water leakage monitoring and resistance, and intensify studies on ''five waters'' transformation at the basin scale. The research results and implication are an important reference for developing water-saving agriculture, solving the shortage of agricultural water resources, ensuring the sustainability of agriculture and improving farmers' living standards. Rational use of agronomic water-saving measures is of great significance to enhance the utilization efficiency of water resources and boost regional economy in karst desertification areas.

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.

The development of nanocellulose (CNCs) chiral liquid crystal photonic elastomeric vitrimer materials is promising for achieving needed reduction in carbon emissions (elastomer material recycling) and developing novel photonic functional materials. The primary questions discussed are about what is the basic principle of chiral liquid crystal and photonic property of CNCs, how to design vitrimer elastomer materials, and what is the general approach to designing CNC chiral liquid crystal photonic elastomer vitrimer and mechanosensitive colour-changing materials.

The development of biomass (e.g., lignin, cellulose or vegetable oil)-based reversibly dynamic covalent cross-linked elastomer vitrimer materials is a novel approach to address issues related to the recycling of waste cross-linked elastomer material. The primary questions discussed are about how to design chemically recycled biomass-derived cross-linked elastomer vitrimer materials, what are the potential challenges in sustainable manufacturing of cross-linked renewable resources derived elastomer vitrimer materials, and what are their potential advanced applications under extreme environmental conditions, such as extreme low or high temperature and irradiated environments.

This paper proposes an effective material delivery algorithm to address the challenges associated with Unmanned Aerial Vehicle (UAV) material transportation and delivery, which include complex route planning, low detection precision, and hardware limitations. This novel approach integrates the Whale-Swarm Hybrid Algorithm (WSHA) with the APCR-YOLOv8 model to enhance efficiency and accuracy. For path planning, the placement paths are transformed into a Generalized Traveling Salesman Problem (GTSP) to be able to compute solutions. The Whale Optimization Algorithm (WOA) is improved for balanced global and local searches, combined with an Artificial Bee Colony (ABC) Algorithm and adaptive weight adjustment to quicken convergence and reduce path costs. For precise placement, the YOLOv8 model is first enhanced by adding the SimAM attention mechanism to the C2f module in the detection head, focusing on target features. Secondly, GhoHGNetv2 using GhostConv is the backbone of YOLOv8 to ensure accuracy while reducing model Params and FLOPs. Finally, a Lightweight Shared Convolutional Detection Head (LSCDHead) further reduces Params and FLOPs through shared convolution. Experimental results show that WSHA reduces path costs by 9.69% and narrows the gap between the best and worst paths by about 34.39%, compared to the Improved Whale Optimization Algorithm (IWOA). APCR-YOLOv8 reduces Params and FLOPs by 44.33% and 34.57%, respectively, with mAP@0.5 increasing from 88.5 to 92.4 and FPS reaching 151.3. This approach can satisfy the requirements for real-time responsiveness while effectively preventing missed, false, and duplicate detections during the inspection of emergency airdrop stations. In conclusion, combining bionic optimization algorithms and image processing significantly enhances the efficiency and precision of material placement in emergency management.

The medium-intensity karst desertification environment is typically characterized by more rocks and less soil. The abandoned land in the construction areas of the dry-hot river valley hydropower station has more infertile soil, severe land degradation, and very low land productivity. Therefore, it is urgent to improve the soil quality to curb the increasingly degrading land and reuse the construction site. Few studies have focused on the effect of soil restoration and comprehensive evaluation of soil quality with multi-treatment in abandoned land in the dry-hot valley hydropower station construction area. Here, 9 soil restoration measures and 1 control group were installed at the Guangzhao Hydropower Station construction in Guizhou Province, China, for physical and chemical property analysis. In total, 180 physical and 90 chemical soil samples were collected on three occasions in May, August, and December 2022. Soil fertility and quality were evaluated under various measures using membership functions and principal component analysis (PCA). This study showed that almost all measures could enhance soil water storage capacity (The average total soil porosity of 9 soil treatments was 57.56%, while that of the control group was 56.37%). With the increase in soil porosity, soil evaporation became stronger, and soil water content decreased. Nevertheless, no decrease in soil water content was observed in the presence of vegetation cover (soil water content: 16.46% of hairy vetch, 13.99% of clover, 13.77% of the control). They also proved that manure, synthetic fertilizer, and straw could promote total and available nutrients (Soil total nutrient content, or the total content of TN、TP、TK,was presented as: synthetic fertilizer (11.039g kg-2)>fowl manure (10.953g kg-2)>maize straw (10.560g kg-2)>control (9.580g kg-2);Total available nutrient content in soil, or the total content of AN,AP,A,was shown as:fowl manure (1287.670 mg kg-1)>synthetic fertilizer (925.889 mg kg-1)>sheep manure (825.979 mg kg-1)>control (445.486 mg kg-1). They could also promote soil fertility, among which the first two reached the higher comprehensive soil quality. Fertilizer was conducive to improve soil quality and fertility, yet long-term application could cause land degradation like soil non-point source pollution, compaction, and land productivity decline. Ultimately, combining fertilizer with biochar or manure is recommended to improve soil fertility. Biochar and green manure could play an apparent role in soil improvement only when there is abundant soil water. The above views provide theoretical support for curbing soil degradation, improving soil fertility and quality, enhancing land productivity, and promoting the virtuous cycle of the soil ecosystem.

Polypeptides consisting of amino acid (AA) sequences are suitable for high-density information storage. However, the lack of suitable encoding systems, which accommodate the characteristics of polypeptide synthesis, storage and sequencing, impedes the application of polypeptides for large-scale digital data storage. To address this, two reliable and highly efficient encoding systems, i.e. RaptorQ-Arithmetic-Base64-Shuffle-RS (RABSR) and RaptorQ-Arithmetic-Huffman-Rotary-Shuffle-RS (RAHRSR) systems, are developed for polypeptide data storage. The two encoding systems realized the advantages of compressing data, correcting errors of AA chain loss, correcting errors within AA chains, eliminating homopolymers, and pseudo-randomized encrypting. The coding efficiency without arithmetic compression and error correction of audios, pictures and texts by the RABSR system was 3.20, 3.12 and 3.53 Bits/AA, respectively. While that using the RAHRSR system reached 4.89, 4.80 and 6.84 Bits/AA, respectively. When implemented with redundancy for error correction and arithmetic compression to reduce redundancy, the coding efficiency of audios, pictures and texts by the RABSR system was 4.43, 4.36 and 5.22 Bits/AA, respectively. This efficiency further increased to 7.24, 7.11 and 9.82 Bits/AA by the RAHRSR system, respectively. Therefore, the developed hexadecimal polypeptide-based systems may provide a new scenario for highly reliable and highly efficient data storage.

The development of wood derived cellulose nanocrystal (CNCs) based sustainable composites is potential to address the plastic pollution issue. However, because of strong hydrogen bonding interactions inside the CNCs, it is still challenging to obtain composites with satisfied comprehensive performance via the incorporation of CNCs into poly (vinyl alcohol) (PVA) matrix directly, so two strategies combined with dopamine modification, base bath solution and ferric (III) ion treatment were reported to tailor the comprehensive performance of PVA/CNC composites. The comparative study indicated that both of physically cross-linked PDA@CNC/PVA and PVA/CNC composites have obvious improvement in term of mechanical and water resistance property owing to the multiple physical interactions, e.g., hydrogen bonding and ferric ion-carboxyl group coordination interactions as well as catechol group and ferric ion coordination interactions. In addition, the physical performance (water resistance and mechanical property) of cross-linked PVA/CNC composites is more better than that of cross-linked PDA@CNC/PVA composites. Besides, physically cross-linked PVA/CNC composites also showed the water responsive mechanically adaptive property. This work provides the foundation for the further development of direct ink writing four-dimensional printing of physically cross-linked PVA/CNC sustainable composites.

IntroductionPatients suffering from severe acute respiratory distress syndrome (ARDS) are usually treated with mechanical ventilation. Extracorporeal membrane oxygenation (ECMO) has traditionally been considered a life-saving therapy and was reserved as a last resort when other treatment options were exhausted. However, this report outlines our successful initial experience with early implementation of awake venovenous extracorporeal membrane oxygenation (VV-ECMO) in a case of pneumocystis jirovecii pneumonia complicated by severe acute respiratory distress syndrome (ARDS), offering a promising new approach for recovery.Case presentationWe present a case report of the effective application of awake VV-ECMO in a 29 years-old man with severe ARDS caused by pneumocystis jirovecii pneumonia. The patient initially received antibiotic treatment and non-invasive ventilation (NIV) for respiratory distress, but these interventions failed to improve the worsening dyspnea that occurred in the patient. Following the combined antifungal therapy, high-flow nasal cannula (HFNC) oxygen therapy, and VV-ECMO for a duration of 7 days, the patient’s symptoms improved, showing relief.ConclusionAwake VV-ECMO proved to be an effective treatment for critically ill patients with ARDS, avoiding the need for invasive mechanical ventilation. However, increased clinical evidence is needed to verify whether awake ECMO could be widely used in severe ARDS caused by other diseases or conditions.

With the deepening of urbanization in China, the coordinated development of cities in different regions is an important part of the sustainable development of the country, and the reasonable quantification of the unbalanced development of cities in different regions is an important issue facing the society nowadays. Previous studies usually use population data to analyze the power-law distribution law to quantify the imbalance of urban development in different regions, but China’s population data span a large number of years and numerous division criteria, and the results obtained from different population data are widely disparate and have obvious limitations. The paper starts from a fractal perspective and utilizes OpenStreetMap (OSM) data to extract national road intersections from 2015 to 2022, calculates critical distance thresholds for eight years using urban expansion curves, generates urban agglomerations in China, and quantifies the imbalance of urban development in different regions by calculating the urban agglomeration power-law index. The results indicate that (1) the critical distance threshold of urban expansion curves exhibits a slight overall increase and stabilizes within the range of 120–130 m, (2) the number of urban agglomerations in China has been increasing significantly year by year, but the power-law index has been decreasing from 1.49 in 2015 to 1.36 in 2022, and (3) the number of urban agglomerations and the power–law index of the Beijing–Tianjin–Hebei, Yangtze River Delta, Pearl River Delta, and Chengdu–Chongqing regions, which is consistent with the national scale trend, indicates that the scale distribution of urban agglomerations in China at this stage does not conform to Zipf’s law, and there is a certain Matthew effect among cities in different geographic areas with a large unevenness. The results of the study can provide new ideas for assessing the coordinated development of cities in different regions. It compensates for the instability of population and economic data in traditional studies.

Against the background of global environmental changes and the intensification of human activity, the village ecosystem faces enormous challenges. In particular, the rural areas in South China Karst face serious problems, such as karst desertification and human–land conflicts. In recent decades, the Chinese government and scientific researchers have committed to controlling karst desertification. However, village ecosystems in the context of karst desertification control (KDC) remain fragile. To promote the sustainable development of villages in KDC, this study considered village ecosystems in different karst desertification areas as study cases. Based on the model of susceptibility-exposure-lack of resilience, we constructed an index system of vulnerability research, used the entropy method to determine the weight, and introduced a contribution model to clarify the vulnerability level and vulnerability driving factors to recommend related governance strategies. We found that (1) the village ecosystem vulnerability levels under KDC were different. Village ecosystems were mildly vulnerable in none-potential KDC areas, moderately vulnerable in potential-mild areas, and moderately and highly vulnerable in moderate–severe KDC areas. (2) The combined effects of the natural environment and human activity have led to the vulnerability of village ecosystems in KDC in South China Karst. Among them, topography, climate, forest coverage, landscape pattern, soil erosion, karst desertification, economic development level, and production and living activity are the main factors affecting the village ecosystem vulnerability of KDC in South China Karst, and the differences in these factors lead to differences in vulnerability levels of different village ecosystems. (3) We designed adaptive governance strategies for village ecosystems based on the factors influencing the characteristics and vulnerability of different karst desertification areas, with the primary goal of sustainable development. They provide a decision-making basis for promoting sustainable development of the village ecosystems in KDC.

Abstract The human skin, an important sensory organ, responds sensitively to external stimuli under various harsh conditions. However, the simultaneous achievement of mechanical/thermal sensitivity and extreme environmental tolerance remains an enormous challenge for skin‐like hydrogel‐based sensors. In this study, a novel skin‐inspired hydrogel–elastomer hybrid with a sandwich structure and strong interfacial bonding for mechanical–thermal multimode sensing applications is developed. An inner‐layered ionic hydrogel with a semi‐interpenetrating network is prepared using sodium carboxymethyl cellulose (CMC) as a nanofiller, lithium chloride (LiCl) as an ionic transport conductor, and polyacrylamide (PAM) as a polymer matrix. The outer‐layered polydimethylsiloxane (PDMS) elastomers fully encapsulating the hydrogel endow the hybrids with improved mechanical properties, intrinsic waterproofness, and long‐term water retention (>98%). The silane modification of the hydrogels and elastomers imparts the hybrids with enhanced interfacial bonding strength and integrity. The hybrids exhibit a high transmittance (~91.2%), fatigue resistance, and biocompatibility. The multifunctional sensors assembled from the hybrids realize real‐time temperature (temperature coefficient of resistance, approximately −1.1% °C−1) responsiveness, wide‐range strain sensing capability (gauge factor, ~3.8) over a wide temperature range (from −20°C to 60°C), and underwater information transmission. Notably, the dual‐parameter sensor can recognize the superimposed signals of temperature and strain. The designed prototype sensor arrays can detect the magnitude and spatial distribution of forces and temperatures. The comprehensive performance of the sensor prepared via a facile method is superior to that of most similar sensors previously reported. Finally, this study develops a new material platform for monitoring human health in extreme environments.

Abstract Uncontrollable zinc dendrite growth and parasitic reactions have greatly hindered the development of high energy and long life rechargeable aqueous zinc‐ion batteries. Herein, the synergic effect of a bifunctional lignin‐containing cellulose nanofiber (LCNF)‐MXene (LM) layer to stabilize the interface of zinc anode is reported. On one hand, the LCNF provides enough strength (43.7 MPa) at relative low porosity (52.2%) to enable the diffusion limited dendrite suppression, while, on the other hand, the MXene serves as a zinc gating layer, facilitating the zinc ion mobility, restricting the active water/anions from degradation in the electrode/electrolyte interface, and epitaxially guiding zinc deposition along (002) plane. Benefiting from the synergic effect of diffusion limited dendrite suppression and zinc gate, the LM layer enabled a high coulombic efficiency (CE) of 98.9% with a low overpotential of 43.1 mV at 1 mA cm−2 in Zn//Cu asymmetric cells. More importantly, Zn//MnO2 full cells with the LM layer achieve a high‐capacity retention of 90.0% for over 1000 cycles at 1 A g−1, much higher than the full cell without the protective layer (73.9% over 500 cycles). The work provides a new insight in designing a dendrite‐free zinc anode for long‐cycle‐life batteries.

The conversion and utilization of carbon dioxide (CO2) have dual significance for reducing carbon emissions and solving energy demand. Catalytic reduction of CO2 is a promising way to convert and utilize CO2. However, high-performance catalysts with excellent catalytic activity, selectivity and stability are currently lacking. High-throughput methods offer an effective way to screen high-performance CO2 reduction catalysts. Here, recent advances in high-throughput screening of electrocatalysts for CO2 reduction are reviewed. First, the mechanism of CO2 reduction reaction by electrocatalysis and potential catalyst candidates are introduced. Second, high-throughput computational methods developed to accelerate catalyst screening are presented, such as density functional theory and machine learning. Then, high-throughput experimental methods are outlined, including experimental design, high-throughput synthesis, in situ characterization and high-throughput testing. Finally, future directions of high-throughput screening of CO2 reduction electrocatalysts are outlooked. This review will be a valuable reference for future research on high-throughput screening of CO2 electrocatalysts.

BIM-based coordination facilitates the discovery of potential pipeline design and construction conflicts. However, the impact of BIM on-field productivity of MEP (Mechanical, Electrical, and Plumbing) installation is unclear because of lacking identification of influencing factors. To fill this research gap, an extensive literature review and quantitative analysis are conducted to identify MEP installation productivity’s impact factors. The identified 24 impact factors are categorized into four primary categories: organizational, management, technical, and personnel. A questionnaire is then designed to measure the impact significance, and the feedback is analyzed through the analytic hierarchy process (AHP) method. This paper finds that: (1) organizational management and control at the macro-level impact productivity more than specific technology and operation during the MEP installation; (2) the key factors affecting productivity are project delivery method, contract mode, and quality control (rework). Accordingly, strategies and suggestions are put forward to encourage and implement productive BIM adoption.

Solar vapor generation is emerging as one of the most important sustainable techniques for harvesting clean water using abundant and green solar energy. The rational design of solar evaporators to realize high solar evaporation performances has become a great challenge. Here, a porous solar evaporator with integrative optimization of photothermal convention, water transport and thermal management is developed using attractive Pickering emulsions gels (APEG) as templated and followed by interfacial engineering on a molecular scale. The APEG-templated porous evaporators (APEG-TPEs) are intrinsically thermal insulation materials with a thermal conductivity = 0.039 W·m−1·K−1. After hydrolysis, t-butyl groups on the inner-surface are transformed to carboxylic acid groups, making the inner-surface hydrophilic and facilitating water transport through the inter-connected pores. The introduction of polypyrrole layer endows the porous materials with a high light absorption of ~97%, which could effectively convert solar irradiation to heat. Due to the versatility of the APEG systems, the composition, compressive modulus, porosity of APEG-TPEs could be well controlled and a high solar evaporation efficiency of 69% with an evaporation rate of 1.1 kg·m−2·h−1 is achieved under simulated solar irradiation. The interface-engineered APEG-TPEs are promising in clean water harvesting and could inspire the future development of solar evaporators.

Talc is a popular filler for the fabrication of plastic composites. The presence of talc helps improve mechanical, thermal, and flame resistance properties of the composite. In this work, we report the influence of a talc-filled plastic shell layer on thermal stability and fire flammability of the core-shell structured wood high-density polyethylene (HDPE) composites manufactured through coextrusion. The result showed that morphological analysis of the char layer after combustion confirmed the formation of a continuous surface char layer with talc addition in the composites, helping block fire penetration and enhance overall fire resistance of the composites. The shell thickness averaged at 1.0±0.2 mm, which represents a fair thick shell over a 10 mm thick WPC core layer. The surface of regular wood-filled HDPE showed large cracks, allowing more rapid fire penetration and reducing its fire resistance. At 800°C, average residual weight for all composite was 21.5±13.8%, most of which was attributed to the inorganic nonvolatile talc components. With the increase of talc level, THR values of coextruded WPC decreased from 302.47 MJ/m2 (5 wt% of talc) to 262.96 kW/m2 (50 wt% of talc). When talc content in the shell layer was less than 25 wt%, the flame resistance properties were slightly enhanced compared with the composites containing unmodified HDPE shells. When talc content in the shell exceeded 25 wt%, the composite’s total heat release and its rate substantially decreased.

ABSTRACT Although distinct lipid phosphatases are thought to be required for processing lipid A (component of the outer leaflet of the outer membrane), glycerophospholipid (component of the inner membrane and the inner leaflet of the outer membrane), and undecaprenyl pyrophosphate (C55-PP; precursors of peptidoglycan and O antigens of lipopolysaccharide) in Gram-negative bacteria, we report that the lipid A 1-phosphatases, LpxEs, functionally connect multiple layers of cell envelope biogenesis in Gram-negative bacteria. We found that Aquifex aeolicus LpxE structurally resembles YodM in Bacillus subtilis, a phosphatase for phosphatidylglycerol phosphate (PGP) with a weak in vitro activity on C55-PP, and rescues Escherichia coli deficient in PGP and C55-PP phosphatase activities; deletion of lpxE in Francisella novicida reduces the MIC value of bacitracin, indicating a significant contribution of LpxE to the native bacterial C55-PP phosphatase activity. Suppression of plasmid-borne lpxE in F. novicida deficient in chromosomally encoded C55-PP phosphatase activities results in cell enlargement, loss of O-antigen repeats of lipopolysaccharide, and ultimately cell death. These discoveries implicate LpxE as the first example of a multifunctional regulatory enzyme that orchestrates lipid A modification, O-antigen production, and peptidoglycan biogenesis to remodel multiple layers of the Gram-negative bacterial envelope. IMPORTANCE Dephosphorylation of the lipid A 1-phosphate by LpxE in Gram-negative bacteria plays important roles in antibiotic resistance, bacterial virulence, and modulation of the host immune system. Our results demonstrate that in addition to removing the 1-phosphate from lipid A, LpxEs also dephosphorylate undecaprenyl pyrophosphate, an important metabolite for the synthesis of the essential envelope components, peptidoglycan and O-antigen. Therefore, LpxEs participate in multiple layers of biogenesis of the Gram-negative bacterial envelope and increase antibiotic resistance. This discovery marks an important step toward understanding the regulation and biogenesis of the Gram-negative bacterial envelope.

The use of sparse-sampling techniques in NMR data acquisition requires quality assessment criteria for the reconstructed spectra. Here, the authors propose a pair of measurements that might serve as these quality measurements.

The conformational dynamics of a compound has a large effect on ligand/receptor binding. Here, the authors employ NMR spectroscopy to study ligand binding to the enzyme LpxC, discovering an inhibitor envelope that was not identifiable by crystallography and subsequently developing a highly potent inhibitor.

Moisture in wood acting as a plasticizer will strongly affect the wood’s viscoelastic properties. However, achieving the desired moisture content (MC) at elevated temperatures during creep tests is difficult. The aim of this study is to accurately and systematically investigate the creep behavior of birch wood at high temperatures. Experiments were conducted using a dynamic mechanical analyzer with a relative humidity accessory coupled with polyvinylidene chloride (PVDC) film for wrapping samples. Creep behavior was examined at six MCs (0%, 6%, 12%, 18%, 24%, >30%) and 11 temperatures (5 to 105 °C). The MC of wood was strictly and accurately controlled during creep tests. Instantaneous compliance (IC) and creep compliance (CC) increased with the increase of both temperature and MC, with significant changes at higher temperatures and MCs. The effects on IC and CC were more pronounced when the subject was influenced by MC, with readings approximately three times and one time greater than those influenced by temperature, respectively. Dramatic increases in CC were found at certain temperatures and MC values. There was a complex interaction between temperature and MC on IC and CC.

To help better utilize corn stalk (CS), pyrolysis behavior of materials from different parts of the CS including corn stalk without pith, corn root, and corn leaf were analyzed using thermogravimetric analysis (TGA) at heating rates of 5, 10, 20, and 25 °C/min. The apparent activation energies determined by the Friedman method for corn stalk without pith, corn root, and corn leaf were in the range of 26.4 to 103.6 kJ/mol, 37.6 to 69.5 kJ/mol, and 35.0 to 103.9 kJ/mol, respectively, depending on the conversion. The main thermal decomposition occurred within a temperature range of 200 to 350 °C (±10 °C). Most of the volatile materials decomposed at less than a 0.8 conversion rate. At greater than a 0.8 conversion rate, the remaining material was mainly char, and the decomposition of char proceeded at higher conversion rates. Different pyrolysis characteristics in the CS indicated that different treatments should be chosen according to different parts for achieving the optimum conversion rate in practical applications.

The effect of individual and combined particleboard dust (PB dust) and basalt fibers (BFs) on mechanical and thermal expansion performance of the filled virgin and recycled high density polyethylene (HDPE) composites was studied. It was shown that the use of PB dust had a positive effect on improving mechanical properties and on reducing linear coefficient of thermal expansion (LCTE) values of filled composites, because the adhesive of the particle board held the wheat straw fibers into bundles, which made PB dust have a certain aspect ratio and high strength. Compared with the commonly used commercial WPC products, the flexural strength of PB dust/VHDPE, PB dust/RHDPE, and PB dust/VHDPE/RHDEPE at 40 wt% loading level increased by 79.9%, 41.5%, and 53.9%, respectively. When 40 wt% PB dust was added, the crystallization degree of the composites based on three matrixes decreased to 72.5%, 45.7%, and 64.1%, respectively. The use of PB dust can help lower the composite costs and increase its recyclability. Mechanical properties and LCTE values of composites with combined BF and PB dust fillers varied with PB dust and BF ratio at a given total filler loading level. As the BF portion of the PB dust/BF fillers increased, the LCTE values decreased markedly, which was suggested to be able to achieve a desirable dimensional stability for composites. The process provides a useful route to further recycling of agricultural wastes.

Weathering of wood--plastic composites (WPCs) leads to discoloration and cracks, which greatly limits their outdoor application. In this study, light stabilizers (including UV-327, HS-944 and nano-SiO2) were added to the shell of a co-extruded high-density polyethylene-based WPC to improve its anti-ultraviolet (UV) ageing properties and simultaneously to maintain its good mechanical properties. The results showed that UV-327 was the most effective light stabilizer for improving the mechanical and anti-UV ageing properties of the composites among the three stabilizers used. WPC samples combined with 2% UV-327 had the highest retention rates in flexural strength and also had the smoothest surface after 2500 h of UV ageing. The samples with 2% UV-327 added had the best protection for discoloration, showing the lowest values of ΔE* (colour difference) and ΔL* (luminescence) in all samples after 2500 h of UV ageing. WPC samples with 2% UV-327 were also oxidized the least after 2500 h of UV ageing. The results reported herein serve to enhance our understanding of the efficiency of light stabilizers in preventing UV degradation of WPCs, with a view to developing co-extruded WPCs with low cost, high anti-UV ageing properties and good mechanical properties for outdoor applications.

Freshly-felled Chinese fir (Cunninghamia lanceolate), Masson Pine (Pinus massoniana) and Camphor Tree (Cinnamomum camphora) logs were reconstituted to form laminated lumber with moisture content above fiber saturation point by slicing, finger-jointing, gluing, and cold-pressing processes. The laminated lumber was then sliced into wood veneers, which were air-dried to about 15% moisture content. The surface roughness of the veneer was tested in comparison with two commercial engineered wood veneers using a stylus tracing method. The influence of the wood surface roughness was relatively small for the wood species chosen due to their similar densities. All roughness parameter values were consistently larger along the transverse direction compared with these along longitudinal direction. The values of surface roughness at the finger-joint region were higher than these that at the non-finger-joint region along both longitudinal direction and transverse direction. The two engineered wood veneers had surface roughness values noticeably smaller in the longitudinal direction, but their values in transverse direction were comparable and even larger compared with these of the prepared wood veneers including both non-finger-joint and finger-joint regions. Overall, the process of laminating finger-jointed green wood planks and subsequently slicing can be used to yield acceptable wood veneers with sufficient surface quality.

Recently, with the development of personal wearable electronic devices, the demand for portable power is miniaturization and flexibility. Electro-conductive hydrogels (ECHs) are considered to have great application prospects in portable energy-storage devices. However, the synergistic properties of self-healability, viscoelasticity, and ideal electrochemistry are key problems. Herein, a novel ECH was synthesized by combining polyvinyl alcohol-borax (PVA) hydrogel matrix and 2,2,6,6-tetramethylpiperidine-1-oxyl (TEMPO)-cellulose nanofibers (TOCNFs), carbon nanotubes (CNTs), and polyaniline (PANI). Among them, CNTs provided excellent electrical conductivity; TOCNFs acted as a dispersant to help CNTs form a stable suspension; PANI enhanced electrochemical performance by forming a “core-shell” structural composite. The freeze-standing composite hydrogel with a hierarchical 3D-network structure possessed the compression stress (~152 kPa) and storage modulus (~18.2 kPa). The composite hydrogel also possessed low density (~1.2 g cm−3), high water-content (~95%), excellent flexibility, self-healing capability, electrical conductivity (15.3 S m−1), and specific capacitance of 226.8 F g−1 at 0.4 A g−1. The fabricated solid-state all-in-one supercapacitor device remained capacitance retention (~90%) after 10 cutting/healing cycles and capacitance retention (~85%) after 1000 bending cycles. The novel ECH had potential applications in advanced personalized wearable electronic devices.

Wood plastic composites (WPCs) offer various advantages and potential as a competitive alternative to conventional noise barriers. For this purpose, the influence of composite formulation on the sound transmission loss (TL) of WPCs needs to be fully understood. In TL testing, stiffness and surface density are major factors influencing the sound insulation property of filled plastics and WPCs. Experimental TL values decreased as sound frequency increased; and the TL values increased after passing a certain frequency level. The comparison of experimental TL curves among filled composites showed that the addition of fillers led to an increase in resonance frequency and TL values. However, at high filling levels, the stiffness decrease led to TL reductions. The experimental TL curves of filled composites, composed of mass law and stiffness law predictions, were well approximated with their combined TL predictions.

Temperature is one of the most important parameters in biohydrogen production by way of photo-fermentation. Enzymatic hydrolysate of corncob powder was utilized as a substrate. Computational fluid dynamics (CFD) modeling was conducted to simulate the temperature distribution in an up-flow baffle photo-bioreactor (UBPB). Commercial software, GAMBIT, was utilized to mesh the photobioreactor geometry, while the software FLUENT was adopted to simulate the heat transfer in the photo-fermentation process. The inlet velocity had a marked impact on heat transfer; the most optimum velocity value was 0.0036 m•s-1 because it had the smallest temperature fluctuation and the most uniform temperature distribution. When the velocity decreased from 0.0036 m•s-1 to 0.0009 m•s-1, more heat was accumulated. The results obtained from the established model were consistent to the actual situation by comparing the simulation values and experimental values. The hydrogen production simulation verified that the novel UBPB was suitable for biohydrogen production by photosynthetic bacteria because of its uniform temperature and lighting distribution, with the serpentine flow pattern also providing mixing without additional energy input, thus enhancing the mass transfer and biohydrogen yield.

In this study, water absorption and desorption behaviors of wood-plastic composites (WPCs) treated with ultraviolet agents and zinc borate were investigated. Water diffusion characteristics in the composites were analyzed using a one-dimensional diffusion model. The mechanism of water sorption for all composites deviated from Fick’s law of diffusion. Much larger diffusion coefficient values are observed from the desorption process when compared to the absorption process. Measured final equilibrium moisture content and calculated diffusion coefficients varied with sample formulation in a non-consistent manner; this indicated that the durability treatment used in the current study did not negatively affect the water sorption behavior of WPCs. The results of this study help to clarify the effect of durability treatment on the dynamic moisture sorption process of WPCs.

A comparative analysis of photostabilizing effects of hindered amine light stabilizers (HALSs), an ultraviolet absorber (UVA), and zinc borate (ZnB) on wood plastic composites (WPCs) was made in this study to show the influence of the accelerated weathering on the surface degradation and loss of mechanical properties of treated WPCs. The results showed that the UVA was the most effective in preventing composite from being bleached, especially when the aging time was longer than 1000 hours. With the addition of the ultraviolet stabilizers, the contact angles increased, indicating increased water wettability. The contact angle of UVA-containing samples was greater than that of the control and the other samples treated with HALSs and ZnB. Flexural properties of all materials decreased after being weathered under xenon-arc light. Materials treated with UVA had higher retention rates in flexural strength and modulus. The results show that, among the agents used, UVA was the most effective additive in preventing WPCs from ultraviolet degradation.

The synthesis of biomass-derived porous carbons (PCs) for supercapacitors by conventional two-steps method (chemical activation after carbonization) is complicated and time-consuming. In this study, we present a one-step microwave activation strategy to prepare hierarchically PCs from waste palm boosted by activated carbons (ACs). ACs with various specific surface areas (14, 642, and 1344 m2·g−1) were used for the first time to fast absorb microwave energy for converting waste palm into hierarchically PCs, that is, PC1, PC2, and PC3, respectively. The morphological and structural characterizations of PCs were studied. Also, the electrochemical performances of supercapacitors based on PCs as electrodes were further investigated. The results showed that the PC (PC1) boosted by AC with the lowest specific surface area possessed a porous structure (containing micro-, meso-, and macro- pores) with the largest specific surface area (1573 m2·g−1) and the highest micropore volume (0.573 cm3·g−1), as well as the suitable mesoporosity (29.69%). The as-prepared PC1 supercapacitor even in a gel electrolyte (PVA/LiCl) exhibited a high specific capacitance of 226.0 F·g−1 at 0.5 A·g−1 and presented excellent charge-discharge performance with an energy density of 72.3 Wh·kg−1 at a power density of 1.4 kW·kg−1 and 50.0 Wh·kg−1 at 28.8 kW·kg−1. Moreover, this promising method exhibited a simple, rapid, and cost-effective preparation of carbon materials from renewable biomass for energy storage applications.

To modify water absorption properties of bamboo fiber (BF) and high density polyethylene (HDPE) composites, heat treatment of BFs was performed prior to compounding them with HDPE to form the composites. The moisture sorption property of the composites was measured and their diffusion coefficients (Dm) were evaluated using a one-dimensional diffusion model. Moisture diffusion coefficient values of all composites were in the range of 0.115x10-8 to 1.267x10-8 cm2/s. The values of Dm decreased with increasing BF heat-treatment temperature, and increased with increasing BF loading level. The Dm value of 40 wt% bamboo fiber/HDPE composites with BFs treated with 100 oC was the greatest (i.e., 1.267x10-8cm2/s). Morphology analysis showed increased fiber-matrix interfacial bonding damage due to fiber swelling and shrinking from water uptaking and drying. The mechanism of water absorption of the composite, indicated a general Fickian diffusion process.

Many bio-based materials, which have lower environmental impact than traditional synthetic materials, show good sound absorbing and sound insulation performances. This review highlights progress in sound transmission properties of bio-based materials and provides a comprehensive account of various multiporous bio-based materials and multilayered structures used in sound absorption and insulation products. Furthermore, principal models of sound transmission are discussed in order to aid in an understanding of sound transmission properties of bio-based materials. In addition, the review presents discussions on the composite structure optimization and future research in using co-extruded wood plastic composite for sound insulation control. This review contributes to the body of knowledge on the sound transmission properties of bio-based materials, provides a better understanding of the models of some multiporous bio-based materials and multilayered structures, and contributes to the wider adoption of bio-based materials as sound absorbers.

Combined decay and mold resistance of zinc borate-(ZB) and calcium borate-(CB) treated oriented strand board (OSB) from southern mixed hardwood (MHW) and southern yellow pine (SYP) was investigated. Tests were done with a brown-rot fungus, Gloeophyllum trabeum, and a white-rot fungus, Trametes versicolor, for 8 and 12 weeks, respectively. Wood species and fungus type had significant influence on the decay resistance. Decay caused by the brown-rot fungus was evident for all untreated SYP and mixed MHW controls. White-rot fungus did not cause significant sample weight loss for either species group. In the SYP OSB control inoculated with G. trabeum, the hyphae were abundant in wood rays and cell walls where they primarily penetrated through bordered and simple pits. The incorporation of ZB and CB into OSB provided significant protection against the fungi with no significant weight loss observed in the treated OSB. Microscopic analysis showed distinct evidence of fungal colonization and a thinning pattern of cell wall material. Untreated OSB samples from MHW and commercial OSBs were most susceptible to mold growth after 6 weeks. The borate-modified OSB from MHW and SYP effectively prevented the mold growth.

Wood plastic composites (WPCs) are increasingly being utilized these days due to their excellent mechanical properties and low maintenance cost. Despite these advantages, poor UV resistance and low impact strength are drawbacks. To overcome these shortcomings, coextrusion technology has recently been applied in the production of WPCs and it has been showing good results. However, further research on the combination of different functional enhancements is still needed. This study, therefore, manufactured polypropylene (PP) composites filled with UV stabilizer and inorganic fillers (i.e., nano-CaCO3 and talc) and then investigated the influence of weathering on the mechanical and morphological properties of the filled composites as a function of filler type and content. UV stabilizer effectively protected the filled composites from UV-induced photodegradation. At 2.5 wt% nano-CaCO3 (NCC), the NCC particles were well dispersed in the PP matrix, thereby improving the mechanical properties of the filled composites. The best results were observed in 2.5 wt% NCC and 10 wt% talc hybrid filled composites. The composites prepared by adding UV stabilizer to the PP matrix together with NCC and talc exhibited high mechanical properties and improved weathering resistance, and, thus, the combination of NCC, talc, and UV stabilizer in the PP matrix is applicable for shell layer to be used in coextruded WPCs.

The effect of bamboo and hybrid bamboo-precipitated calcium carbonate (PCC) fillers on thermal expansion behavior of filled plastic composites was investigated. The linear coefficient of thermal expansion (LCTE) of the filled composites decreased with increased PCC and bamboo filler loading levels. The composite system with refined bamboo fibers (RBFs) had smaller LCTE values compared with those from the systems with ground bamboo particles (GBPs). The use of silane treatment on bamboo fiber/particle surface helped enhance its bonding to the plastic matrix, leading to a further reduction of LCTE values for both GBP and RBF composite systems. The observed behavior of reduced LCTE is attributed to a small filler LCTE value, reduced overall plastic volume, and enhanced interfacial bonding with treated bamboo materials. Thus, hybrid bamboo and PCC fillers are suitable materials for reducing the thermal expansion of the composites caused by temperature changes.

High-Density Polyethylene (HDPE)-based composites with alkaline copper quaternary (ACQ)- and micronized copper quaternary (MCQ)-treated wood fibers were manufactured through injection molding. The mechanical properties, water absorption, and biological resistance properties of the fabricated composites with different coupling treatments were investigated. Composites with ACQ- and MCQ-treated wood had mechanical properties comparable with those made of untreated wood. The different coupling agents worked well for the treated wood materials. Similar water absorption behaviors were observed for the HDPE composites containing treated wood and those containing untreated wood. The results of the termite test showed that the composites containing untreated wood had slightly more weight loss. The decay test revealed that the composites containing treated wood had less decay fungal growth on the surfaces, compared with samples from untreated wood, indicating enhanced decay resistance for the composites from the treated material. The stable mechanical properties and improved biological performances of the composites containing treated wood demonstrated the feasibility of making wood-plastic composites with pressure-treated wood materials, and thus offered a practical way to recycle treated wood into value-added composites.

Coextruded wood-plastic composites (WPCs) with glass-fiber (GF) filled shells were manufactured, and their thermal expansion behavior was studied. A three-dimensional finite element model (FEM) considering differential properties of both shell and core layers was developed to predict the linear coefficient of thermal expansion (LCTE) of the material. It was shown that the LCTE values varied with composite structure and composition (i.e., core-shell thicknesses and materials). The use of GF-filled shells helped lower overall composite LCTE values. The imbalance of shell and core LCTE, and their moduli led to complex stress fields within a given composite system. The FEM predicted a trend of LCTE change with varying composite structures, which was in good agreement with the experimental data. This study provides for the first time a finite element modeling technique to optimize raw material composition and composite structure for optimizing thermal expansion behavior of co-extruded WPCs.

Copper/carbon core/shell nanoparticles (CCCSNs) recently have been introduced as an industrial material. In this paper, composites based on high density polyethylene (HDPE), bamboo fiber, CCCSNs, and coupling agent (MAPE) were prepared by melt compounding. The influence of CCCSN content on the resulting composites’ mechanical, biological resistance, and thermal properties was investigated. It was found that CCCSNs within the carbon black matrix were processed well with bamboo fiber-plastic blends through mixing and injection molding. The materials enhanced composite strength and modulus-related properties. Composites with CCCSNs and natural fibers reduced heat capacity and thermal diffusivity. Composites with CCCSN materials also enhanced termite and mold performance. Thus, the material can be used as additive for plastics and other polymers to modify strength properties, biological resistance (e.g., mold and stain), and thermal conductivity properties.

Formosan subterranean termites (Coptotermes formosanus Shiraki), is estimated to cause hundreds of millions of dollars in losses annually in North America. Unlike most subterranean species, Formosan termites often build nests (cartons) in living trees and wooden buildings, and even penetrate plaster, plastic, asphalt, mortar, creosote, concrete, and rubber to reach wood. The study addresses issues that U.S. home owners consider in evaluating whether to buy or build homes that are built with termite resistant building materials. The sample frame for this study consisted of a random sample of 5.000 home owners in the region where Formosan subterranean termites are a current or potential problem. When examined by state, 50 percent of respondents in Hawaii said termites have damaged the home they currently live in followed by respondents from Louisiana and California. On average, respondents indicated that preservative pressure treated wood and regular fumigation as being most effective in protecting a house against termites and only 8 percent of respondents said they would not pay a premium for a guaranteed termite-free new home.

Creep performance of zinc borate-treated strandboard from southern pine (Pinus taeda L.) and red oak (Quercus falcata) was investigated at 25(0)C temperature and 65% relative humidity. It was shown that the borate treatment had some significant effect on creep deflection of the test panels, and the effect varied with wood species. There was no significant effect of creep loading on residual bending properties of treated strandboard under the stress levels used. The four element spring-dashpot creep model fitted the creep data well. The predicted creep deflection for a 10-year loading duration under both 15% and 40% stress levels met the National Design Specification for Wood Construction despite of the noticeable borate treatment effect on creep. Future work is needed to study the creep behavior under combined mechanical and moisture loadings for treated structural panels.

Reinforcing effect of hybrid filler including wheat straw (WS) and inorganic filler (heavy calcium carbonate, silicon dioxide, and fly ash) in recycled polypropylene (R-PP) has been investigated. The effects of individual filler (WS) and combined fillers (WS and inorganic filler) on morphological, mechanical, and thermal expansion and water absorption properties of hybrid composites were investigated. The flexural modulus and flexural strength were both reduced when reinforced with three kinds of inorganic fillers, respectively, which was possibly due to the poor interphase adhesion as observed in SEM. The high surface energy of heavy calcium carbonate due to its high acidic character provides an opportunity of better PP-heavy calcium carbonate interfacial interactions compared to PP-straw, PP-fly ash, and PP-SiO2 interface. The water absorption at saturation increased markedly by introduction of WS in it. The hybrid composites from WS and inorganic fillers showed better water absorption compared to those WS/PP composites. The thermal expansion of composites decreased with the increase of WS loading. Heavy calcium and SiO2 can obviously reduce the LCTE value of composite. At the 25% inorganic filler content, composites had the smallest LCTE values.

The effect of heat-treated bamboo fibers (BFs) on nonisothermal crystallization of high-density polyethylene (HDPE) was investigated using differential scanning calorimetry under nitrogen. The Avrami-Jeziorny model was used to fit the measured crystallization data of the HDPE/BF composites and to obtain the model parameters for the crystallization process. The heat flow curves of neat HDPE and HDPE/heat-treated BF composites showed similar trends. Their crystallization mostly occurred within a temperature range between 379 K and 399 K, where HDPE turned from the liquid phase into the crystalline phase. Values of the Avrami exponent (n) were in the range of 2.8~3.38. Lamellae of neat HDPE and their composites grew in a three-dimensional manner, which increased with increased heat-treatment temperature and could be attributed to the improved ability of heterogeneous nucleation and crystallization completeness. The values of the modified kinetic rate constant (KJ) first increased and then decreased with increased cooling rate because the supercooling was improved by the increased number of nucleating sites. Heat-treated BF and/or a coupling agent could act as a nucleator for the crystallization of HDPE.