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Background and Objectives: In the past two decades, sustainable biological nanomaterials like nanocellulose, encompassing bacterial nanofibers cellulose and wood cellulose nanofibers, have received considerable attention among researchers for diverse product applications. Key attributes such as biocompatibility, biodegradability, renewability, cost-effectiveness, abundant raw material availability, suitable mechanical properties, and safety stand out as pivotal features of biological nanomaterials. Leveraging these properties has led to the creation of numerous applications within various industries. An intriguing product arising from this realm is nanofilm, which is crafted through hydrogen bond formation between cellulose nanofibers, obviating the need for additives or adhesives during production. When utilized as a reinforcement in layered nanocomposite construction, bacterial cellulose nanofibrils (BCNF) and wood cellulose nanofibers (WCNF) exhibit exceptional reinforcement capabilities owing to the inherent cellulose network structure. The recent surge in nanocomposite production emphasis, property optimization, and utilization of high-tech products underscores the growing significance of nanofibrillated cellulose. Recognizing the technical and practical significance of cellulose-layered wood nanocomposite, cellulose nanofilm layers, and the nanocomposites derived from them, coupled with the imperative to thoroughly investigate and evaluate these materials for prospective applied research, this study aims to assess and compare the physical and mechanical properties of cellulose layered wood nanocomposites and bacterial nanocomposites. Materials and Methods: In this study, wood cellulose nanofiber gel and bacterial cellulose nanofiber film were employed. To create wood cellulose nanofiber layered nanocomposites, an initial wood cellulose nanolayer was fabricated using wood cellulose nanofibers and a vacuum-filtration method. Subsequently, the nanolayers underwent solvent displacement with ethanol and acetone through multiple cycles. A mixture of epoxy resin, hardener, and acetone in a 20:10:70 ratio was prepared and agitated on a magnetic stirrer to eliminate bubbles. The cellulose nanolayer was then coated with this epoxy resin, stacking four layers atop one another to form a layered nanocomposite, which was then subjected to a heat press machine and dried for 3 hours at 60 °C. The manufacturing process for bacterial cellulose layered nanocomposites mirrored that of wood cellulose layered nanocomposites, with the distinction that the bacterial cellulose nanofiber film was dried in a hot press at 70 °C for 3 hours to create the bacterial cellulose nanolayer, followed by the assembly of the respective layered nanocomposite. The properties of the resulting nanocomposites were evaluated using various tests, including scanning electron microscopy (FESEM), X-ray diffraction (XRD), infrared spectroscopy (ATR-FTIR), static tension, and water absorption assessments. Results: The study revealed that the average diameter of bacterial nanocellulose and wood nanocellulose measured 45±15 nm and 38±16 nm, respectively. The water absorption of the layered nanocomposite was lower than that of the nanolayer in both nanostructures. Notably, the XRD peaks of bacterial nanocellulose and wood nanocellulose exhibited distinct patterns, with crystallinity levels calculated at 87% and 69%, respectively. Furthermore, the elastic strength, Young's modulus, and strain of the layered nanocomposite composed of bacterial nanocellulose surpassed those of the equivalent composite made from wood nanocellulose. Conclusion: The layered nanocomposites crafted from cellulose nanofibers showcased commendable physical and mechanical attributes, including minimal water absorption and heightened durability. Given these promising characteristics and the escalating interest in related research, it is anticipated that these materials will soon find expanded applications in diverse sectors such as aerospace, automotive, medical and biomedical engineering, food production, film industry, electronics, and magnetism, among others. [ABSTRACT FROM AUTHOR]

Background and Objectives: Fine dust air pollution poses a significant health threat in arid and semi-arid regions worldwide. Inhaling these particles is linked to cardiovascular issues, reduced lung function, skin problems, respiratory irritation, and an increased risk of cancer. Existing respiratory masks often struggle to capture these fine particles (less than 2.5 microns) due to the limitations of conventional filter materials. This study explored enhancing respiratory filter performance by applying a deep-coating method with cellulose nanofibers (CNFs) on a cellulosic substrate. We investigated CNF concentrations of 0.05%, 0.1%, 0.2%, and 0.5%. Coated filters were freeze-dried at -50 °C and 0.04 mbar pressure. These modifications aimed to improve filter absorption capacity, addressing the limitations of conventional filters and offering a novel approach to mitigate health risks from fine dust inhalation. Materials and Methods: Wood cellulose nanofiber gel (WCNFs) was obtained from Nano Novin Polymer Co., Iran. Carboxymethyl cellulose (CMC) and citric acid (CA) were purchased from Dr. Mojallali Co., Iran. The cotton fabric substrate came from Live Co., Iran. Sample characterization employed Fourier-transform infrared spectroscopy (ATR-FTIR), X-ray diffraction (XRD), filter pressure drop measurement, field-emission scanning electron microscopy (FESEM), and a fine particle adsorption test. Results: The FTIR test confirmed the purity of the cellulosic substrate used for CNF coating. XRD analysis revealed the presence of β1-cellulose in the substrate, indicated by distinct peaks at 2θ angles of 15.5°, 16.5°, 22.5°, and 34.5°. This structure facilitated strong bonding between CNFs and the substrate. FESEM imaging confirmed the presence of nanofibers (below 100 nm), enabling the formation of nano- and submicron pores. While increasing CNF concentration generally raised pressure drop, the optimal treatment involved a 5-layer sample with two layers containing 0.5% CNFs. This configuration achieved a remarkable 96.18% absorption efficiency for particles smaller than 2 microns, exceeding the N95 standard set by the Food and Drug Administration. [ABSTRACT FROM AUTHOR]

Background and Objectives: Nanocellulose aerogels are ultralight, porous materials with high potential in diverse fields. The preparation of nanocellulosic aerogels consists of two main steps: preparation of hydrogel from a solution and removal of solvent through sublimation by freeze drying or supercritical method with solvent exchange. Due to desirable characteristics such as ultra-light density, porous structure, biodegradability, and being environmentally friendly, these materials have a wide range of applications in various industries, such as medicine, pharmaceutical, military, defense, etc. Despite the above advantages, they also have disadvantages such as flammability when exposed to heat or fire, which limits their use in many cases. This study explores the development of flame-retardant nanocellulose aerogels using sodium bicarbonate (SBC) modification. Materials and Methods: This study focuses on the preparation of nanocellulose aerogels with flame-retardant properties using sodium bicarbonate. A 2% wt concentration nanocellulose gel was obtained from Nanonovin Polymer Company and used as the base material. Sodium bicarbonate was added to the nanocellulose gel at a concentration of 20% wt of the dry weight to achieve flame retardancy. The resulting suspension was stirred at 1200 rpm for 30 minutes to form a uniform hydrogel. Control nanocellulose (CNF) and sodium bicarbonate-treated (CNF+SBC) hydrogels were then poured into copper molds and refrigerated at 2 °C for 24 hours. Subsequently, the molds were transferred to a liquid nitrogen bath for rapid freezing. The frozen samples were then subjected to freeze-drying for 48 hours to obtain control and treated nanocellulose aerogels. Results: The presence of sodium bicarbonate in the flame-retarded aerogels was confirmed through FTIR spectroscopy. SEM and BET analysis revealed that the addition of sodium bicarbonate reduced the porosity and specific surface area of the nanocellulosic aerogel. Thermal characterization demonstrated that the flame-retarded nanocellulose aerogels exhibited higher thermal stability compared to the control aerogels, with approximately 30% more residue remaining after combustion. Flammability tests further supported this finding, indicating that the presence of carbon dioxide hindered further burning of the aerogel by limiting oxygen availability during ignition. The crystalline structure of cellulose in the sodium bicarbonate-treated aerogels remained unchanged compared to the control, while the compression strength and modulus of the treated aerogel decreased due to a decrease in the polymerization degree. The lightweight and flame-retarded nature of these nanocellulose aerogels makes them suitable for various applications in industries such as construction, oil and gas, textiles, and energy storage. Conclusion: The treatment of nanocellulose aerogels with sodium bicarbonate resulted in the production of lightweight and environmentally friendly aerogels with flame-retardant properties. These findings offer the potential for their utilization in industries requiring thermal insulation and energy storage, emphasizing their green and sustainable characteristics. [ABSTRACT FROM AUTHOR]

Background and Objectives: Carbon materials bearing advantages such as chemical and thermal stability, electrical conductivity, high specific surface area, and high porosity are widely used in electrode materials. While wood-based carbon materials exhibit good capacitive behavior and offer increased charge storage capacity, their electrical conductivity is often insufficient for optimal performance as carbon electrodes. To enhance their conductivity, composite materials combining wood-based carbon with other conductive materials have been synthesized. In this study, we assessed the physicochemical and electrochemical properties of nanocomposite electrodes based on carbonized wood/Mn-MOF, which were prepared using the in-situ synthesis method. Additionally, we investigated the performance of these electrodes as cathodes in sediment microbial fuel cells. Furthermore, we compared their performance with that of control wood-based electrodes and commercially available carbon felt electrodes. Materials and Methods: The sapwood blocks of Platanus orientalis were used as a lignocellulosic precursor and subjected to pyrolysis at a temperature of 700 °C. The heating rate was set at 5 °C min-1, and the pyrolysis process took place in an argon atmosphere with a constant flow of 100 mL/min and a retention time of 1 hour. Following pyrolysis, the carbonized wood samples were washed with distilled water and subsequently dried in an oven. To synthesize composite electrodes of CW/Mn-MOF, we employed manganese (II) acetate tetrahydrate and a 1,3,5-benzene tricarboxylic acid ligand. The resulting samples were washed with ethanol and dried once more in the oven. For secondary pyrolysis, the samples were subjected to a temperature of 900 °C for a duration of 2 h in an argon atmosphere, with a heating rate of 5 °C min-1 . Results: The findings revealed that the porous structure and its interconnected and direct channels were successfully maintained after wood pyrolysis. Moreover, the in-situ synthesis of Mn-MOF on carbonized wood was achieved. Raman spectra analysis indicated an increase in the degree of disorder in the structure of the prepared nanocomposite electrodes compared to the control carbonized woods. Additionally, XRD patterns demonstrated the presence of both amorphous and graphitic carbon within the graphitic crystals of carbon. Furthermore, the carbon electrodes doped with Mn-MOF exhibited the lowest impedance and the highest maximum power density when compared to the control and carbon felt electrodes. Conclusion: It was found that high-temperature carbonization leads to the graphitization of wood material, resulting in increased electrical conductivity. The doping of carbon electrodes and the fabrication of carbon-nanocomposite electrodes using carbonized wood/Mn-MOF significantly enhanced the electrochemical performance of the cathode in sediment microbial fuel cells. The combination of the pseudocapacitive behavior of Mn-MOF and the electrical double-layer capacitance behavior of the carbon material exhibited a synergistic effect, which ultimately improved the overall performance of the SMFC setup. [ABSTRACT FROM AUTHOR]

Background and Objectives: Nanocelluloses have attracted the attention of governments and investors due to their wide applications in many industries. The recognition and potential of nanocellulose has encouraged countries to invest in this green product. However, in Iran, nanocellulose production is still at laboratory scale due to unidentified challenges and thus has not yet reached the huge production. The aim of this study is to utilize SWOT method to identify the strengths, weaknesses, opportunities, and risks associated with the proposed application and use of nanocellulose in Iran. Materials and Methods: The factors influencing the supply and demand of nanocellulose were identified and analyzed through three stages Delphi questionnaire. This process involved the participation of 10 experts, including academic professors, private manufacturing and technology companies. The internal factors (strengths and weaknesses) and external factors (opportunities and threats) affecting supply and demand of nanocellulose were identified in a separate tables of the SWOT analysis. Results: In the strength subnetwork 8 indicators were identified. These include creating high added value for raw material and nanocellulose products; diversity and availability of raw materials; biocompatibility and biodegradability of nanocellulose products; the ability to produce a new generation of efficient products with nanocellulose; creating sustainable development through the commercialization of nanocellulose; individual energy contribution with high local technical knowledge; less space for nanocellulose production; variety of nanocellulose products. In the weak subnetwork 9 indicators were identified. These include size change of nanocellulose during drying; high cost associated with energy, operation, land, and machinery; need for significant investment; high cost of drying nanocellulose; lack of government and bank investments; low production efficiency; inefficiency of equipment for nanocellulose use; production in the form of nanocellulose gel (with water); expensiveness nanocellulose production method compared to competitors). In the opportunity subnetwork 7 indicators were identified and include use of nanocellulose in various fields; high innovation and novelty in the field of nanocellulose applications; attracting foreign investors and the private sectors; suitable export markets in the region; the possibility of accessing the technical knowledge from other countries' production; need for high-tech research and development; government support for the nanocellulose production industry; rapid transformation of nanocellulose products worldwide. Eventually, in the opportunity subnetwork 8 indicators were identified and include. Availability of raw materials and alternative products; customization potential of nanocellulose; low price of raw materials and competing products; expensiveness of nanocellulose; lack of specialized production machines; Managers' reluctance to take risk in adapting new products; challenges in introducing and promoting new products in the market. Conclusion: The indicators that have significant impact on the supply and demand of nanocellulose were identified by experts using Delphi and SWOT methods. By implementing the proposed solutions, it is possible to achieve mass production and commercialization of nanocellulose in Iran. [ABSTRACT FROM AUTHOR]

Background and Objectives: Magnetic wood is one of the wood nanotechnology products with a wide range of potential industrial applications. Superparamagnetic wood is generally produced by in situ synthesis of magnetic nanoparticles in the wood structure. Among the various wood species used for the production of magnetic wood, fast-growing species are gaining increasingly important. On the other hand, the inherent properties of wood, such as water absorption, dimensional instability, and susceptibility to biodegradation and weathering, may limit the potential of magnetic wood as an advanced engineering material. This study aimed to investigate the effect of furfurylation on modifying the physical and mechanical properties of superparamagnetic poplar wood prepared by in situ synthesis of magnetic nanoparticles. Materials and Methods: In situ synthesis of magnetite nanoparticles inside poplar wood (Populus deltoides) was carried out using a solution of iron II and III chlorides with a molar ratio of 2:1 in a vacuum/pressure chamber. Then the treated wood was converted to magnetic wood by draining the solution of iron cations and replacing it with a one-molar solution of sodium hydroxide. After washing the excess alkali solution and drying, the magnetic poplar wood was treated with two different concentrations of furfuryl alcohol solution under the vacuum/pressure system and converted into wood polymer after performing the required heat treatments. The samples were characterized using a field emission scanning electron microscope, X-ray diffraction, vibrating sample magnetometry, a static bending test, and long-term water absorption and thickness swelling tests. Results: The conversion of poplar wood to magnetic wood reduced the weight percentage gain (WPG) resulting from the furfurylation process. The saturation magnetization of the magnetic wood decreased significantly after furfurylation and conversion to the wood-polymer. Changing the concentration of the furfuryl alcohol solution did not substantially affect the saturation magnetization of the produced magnetic wood-polymers. The furfurylation treatment significantly reduced the samples' flexural strength and flexural modulus. The flexural properties of magnetic and non-magnetic wood polymer samples treated with the same concentration of furfuryl alcohol solution showed no significant difference. Microscopic examination of the fracture surface of the wood cell wall in the specimens subjected to the bending test showed that furfurylation changed the behavior of the fibers from ductile to brittle, which was consistent with the results of the bending test. On the other hand, as the WPG increased, the specimens' long-term water absorption and thickness swelling decreased. Magnetic wood-polymer samples showed higher values for water absorption and thickness swelling than non-magnetic wood-polymer specimens. Conclusion: Based on the results of this study, it is recommended that magnetic poplar wood, if it must be used in high-humidity environments, be converted to magnetic wood-polymer with furfuryl alcohol, provided it has the required mechanical properties. [ABSTRACT FROM AUTHOR]

Background and Objectives: Nanocelluloses have attracted the attention of some countries due to their potential in economic growth. In general, there are produced in two ways: top-down (vegetable nanocellulose) and bottom-up strategy (bacterial nanocellulose). This valuable material is widely used in the technology of various industries. Considering that the nanocellulose industry is juvenal in Iran, its market and industry is not yet well formed, and studying the factors affecting its supply and demand market is important and is the objective of the current study. Materials and Methods: Nanocellulose is facing challenges and therefore it is necessary to identify the important criteria and subcriteria affecting its production and consumption sector. To do so, 10 questionnaires were designed, based on the Delphi survey with 6-Likert scale, and were sent in three stages to experts including: university professors, private companies and production & technology knowledge startups to determine the status of nanocellulose production and consumption. Results: The results obtained showed that in the “raw materials and product” criterion, 11 subcriteria in the first stage, 2 subcriteria of “development of approach” and “access to raw materials inside and outside the province” whose average was < 3 were eliminated in the second stage, 9 subcriteria were remained. In the “economic and sales marketing” criterion among the 13 subcriteria in the first stage, 4 subcriteria “customer satisfaction”, “sales system”, “export opportunities” and “transportation costs” were eliminated with an average of < 3 and 9 subcriteria retained in the second and third stages. In the “competitive and infrastructure” criteria, among the 9 subcriteria, 2 subcriteria “purchasing power of nanocellulose suppliers” and “discount power of nanocellulose suppliers” were removed with an average of < 3 and 7 subcriteria remained in the second and third stages. In the “human technical” criteria, among the 10 subcriteria in the first stage, 3 subcriteria “existence of educational”, “academic-professional pillars” and “living and welfare facilities” were removed with an average of < 3 in the second round and 7 subcriteria were remained. The Cronbach's Alpha reliability of the first stage was 0.825, 0.815 in the second round and 0.845 in the third round. Conclusion: The indicators effecting the production and consumption of nanocellulose sector were significant in the three stages of the questionnaires completed by experts, while Kendall's correlation coefficients was 0.57 in the second and third stage. This indicates the effectiveness of the factors affecting the production and consumption of nanocellulose and should be considered in the process of production, marketing and supply of nanocellulose products in Iran. [ABSTRACT FROM AUTHOR]