Source Of Raw Materials Research Articles

Wastewater treatment in the pulp and paper industry: A review

The pulp and paper industry plays a large role in global manufacturing, which creates significant water consumption and generation of wastewater that is filled with organic compounds and other chemicals. This paper will explore many different aspects of the pulp and paper industry such as raw material sourcing, manufacturing processes, environmental concerns, technological advancements, and the various wastewater treatment approaches. While there are many different methods to approach this wastewater issue, in this paper we will focus on anaerobic digestion, the application of biological aerated filters, and the use of constructed wetlands. The main material utilized in this industry is wood pulp, which undergoes multiple different procedures and processes to create the typical paper products we use every day. These processes, such as pulping and bleaching, create a large number of environmental concerns despite efforts to encourage better manufacturing practices and paper recycling.

Studies on Alkaline Activator, Manufacturing Methods and Mechanical Properties of Geopolymer Concrete - A Review

Continuous production of cement products, a new environmentally responsible geopolymer material, can reduce CO2 emissions from increased cement production. Compared to ordinary Portland cement (O.P.C.) geopolymer concrete, it has better mechanical strength and corrosion and fire resistance. Most industrial solid wastes and bottom ash from waste incineration are disposed of unevenly, which consumes land resources and negatively affects the ecosystem. The best alternative resource for the synthesis of geopolymer composites is recycling. Metals, pesticides, and other radioactive pollutants are successfully absorbed by geopolymer composites, which is very favorable for the ultimate development of civilization. Therefore, this review has examined essential material parameters, including new properties, compressive strength, flexural strength, elastic Modulus, compressive strength, and split-tensile strength applications. According to the previous experimental results, G.P.C. offered better fresh properties than conventional composites. This review revealed the geopolymerization process, the types of alkaline/alkali activators, synthesis techniques, sources of natural raw materials, and applications of geopolymer concrete. The present work discussed the conceptual framework for the sustainable production of geopolymer materials by evaluating the drawbacks, applications, and restrictions of geopolymer materials and their potential development.

Investigation of the chemical and biological composition of the medicinal plant juzgun leucocladum-for further production of an antibacterial veterinary drug

Juzgun (лат. Calligonum) is a genus of perennial deciduous branching shrubs from the Buckwheat family (лат. Polygonaceae). According to some data, up to 158 plants are included in the genus, but since the genus is poorly studied, the definition of the species included in it is considered inaccurate. Moreover, some scientists claim that it is impossible because of multiple morphological differences that do not have geographical certainty. Tannins, citric and phenolic carboxylic acids, alkaloids, leucoanthocyanidins, flavonoids were found in the chemical composition of plants from the genus Juzgun. Plants from the genus Juzgun can potentially serve as a source of medicinal raw materials. Scientists have found phenolcarbonic acids in them, which have a choleretic effect, acting as a hypotensive agent. Antitumor effect is endowed not only with the leucoanthocyanidins present in the representatives of the genus, but also a number of flavonoids.We have investigated the chemical composition and identification of biologically active compounds in the vegetable raw materials of the Juzgun leucocladum. Physico-chemical studies have been carried out. The elemental composition of raw materials has been determined.The morphology of the raw materials was investigated, and the amino acid composition of the raw materials was also determined. The first samples of a veterinary drug based on Juzgun plant raw materials and phytosorbents for veterinary purposes were obtained and sent for clinical research.

Protein Hydrolysates—Production, Effects on Plant Metabolism, and Use in Agriculture

Agriculture is facing challenges to produce more food in a climate scenario that works in the opposite direction. To amend this, agriculture has to invent new ways of making more with less. Interest in using by-products and finding new ways to utilize them has been increasing in recent years. The use of protein-rich sources for protein hydrolyzation and the use of these protein hydrolysates as biostimulants in plant production have been increasing. These mixtures are mainly produced by chemical and enzymatic hydrolysis from agro-industrial protein-rich by-products of animal, plant, and algal origins. The application of PHs has the potential to alleviate environmental stress; improve plant growth; and increase productivity, fruit yield, and abiotic-stress tolerance in agricultural crops. The use of these biostimulants offers a way to reduce the use of agrochemicals and agrees with the “do more with less” task in the future of agricultural production. This review gives an insight into the production of PHs, referring to sources of raw materials and methods of hydrolysis, the uptake and translocation of PHs, their effect on plant growth, the development and physiology, their role in alleviating stressful conditions, and their use in agriculture. The beneficial effects of PHs on different aspects of plant physiology, metabolism, and plant functioning under stressful conditions are evident. Inconveniently, crops, and sometimes even cultivars, are affected differently based on the way that PH is applied, the timing, and the concentration applied. Further research is needed to elucidate the mechanisms by which the components of PHs modify plant physiology and metabolism.

Characterization of Traditional Pottery Artifacts from Yucatán Peninsula, México: Implications for Manufacturing Process Based on Elemental Analyses

The present work is focused on developing and implementing a minimally invasive methodology for material characterization of traditional pottery from Yucatan, México. The developed methodology, which combines elemental (X-ray fluorescence spectroscopy (XRF), inductively coupled plasma-optical emission spectroscopy (ICP-OES), and Laser-Induced Breakdown Spectroscopy (LIBS)) and molecular (fiber optic reflectance spectroscopy (FORS)) spectroscopic analytical techniques, allowed for the characterization of contemporary pottery objects manufactured following traditional recipes in the town of Uayma, Yucatán, México and raw materials associated with the pottery manufacturing process. The results allowed us to detect and estimate the number of selected elements and helped to infer the presence of complex materials such as iron oxides, aluminosilicates, and calcium carbonate. Additionally, the analysis indicated two pottery groups separated by their elemental and molecular composition, corresponding to the sources of raw materials employed by the potters. It confirmed the absence of toxic compounds in ceramic objects, a significant concern for potters, as some objects are intended for domestic use. The research findings provide reassurance about the safety of these products.

Environmental Impact Assessment of a Plant Cell-Based Bio-Manufacturing Process for Producing Plant Natural Product Ingredients

Purpose: This study employed a Life Cycle Assessment (LCA) methodology to evaluate the environmental impacts of a novel plant cell-based biomanufacturing process for producing plant natural product ingredients. The primary purpose was to assess the relative sustainability of the process and to provide insights into potential areas of improvement in the biomanufacturing process. Method: The LCA method used an MS Excel (Ver. 2407) -based approach with a cradle-to-gate system boundary covering raw material sourcing (A1), raw material transportation (A2), and product extract manufacturing (A3) stages. Energy use and material inventory data are presented for different unit operations, and environmental impact factors were obtained from the Ecoinvent database. The study included a Material Circularity Index (MCI) calculation to assess the circularity of the biomanufacturing process for the production of saponin emulsifiers that are normally extracted from the woody tissue of the Chilean soapbark tree (Quillaja saponaria). Comparative analyses were performed against a wild-harvest approach for plant tannin extraction from spruce (Picea abies) tree bark. Key Results: The environmental impact assessment focused on determining relative Global Warming Potential (GWP), Acidification Potential (AP), Freshwater Eutrophication (FE), Particulate Matter Formation (PMF), and Ozone Depletion Potential (ODP). Results indicated that the extract manufacturing stage (A3) contributed significantly to adverse environmental impacts, with varying levels of effects based on the energy source used. Comparative analysis with the wild harvest approach highlights the lower environmental impact of the alternative biomanufacturing process. The biomanufacturing process showed a 23% reduction in GWP, AP, and FE and a 25% reduction in PMF and ODP relative to the wild harvest approach. However, the MCI for the biomanufacturing process was estimated to be 0.186, indicating a low material circularity. Conclusions: The results revealed that the extract manufacturing stage, particularly energy consumption, significantly influences the relative environmental impacts of the alternative production processes. Different energy sources exhibit varying effects, with renewable energy sources showing lower environmental impacts. The Material Circularity Index indicated a low circularity for the biomanufacturing process, suggesting opportunities for improvement, such as incorporating recycled or reused materials. Compared with the tannin extraction process, the plant cell-based biomanufacturing process demonstrated lower environmental impacts, emphasising the importance of sustainable practices and the use of renewable energy sources in future plant natural product sourcing. Recommendations include implementing more sustainable practices, optimising raw material choices, and extending product life spans to enhance circularity and overall environmental benefits.

INVESTIGATION OF WETTABILITY, ANTIBACTERIAL ACTIVITY, THERMAL INSULATION, AND MECHANICAL CHARACTERISTICS OF ELASTOMER BLEND ADHESIVES WITH HIGH-DENSITY FIBERBOARD WOOD AND ALUMINUM

Attention has recently been given to finding alternative and sustainable raw material sources for wood and metal adhesives, such as polyvinyl alcohol (PVA), corn starch (CS), arabic gum (AG), and dextrins (D). Modifying polymer dispersion using unique substances, such as modifying reactive elastomer liquid (EL) using PVA, CS, AG, or D results in sufficiently moisture-resistant adhesive joins. In the present study, the physical characteristics of EL/blended with the natural polymers PVA, CS, AG, and D, based on high-density fiberboard (HDF) wood and aluminum (Al) adhesives and coatings, were investigated and compared to those of pure EL. The EL was blended with PVA, CS, AG, or D at a ratio of 60/40 (w/w) to form EL/blends. The chemical structures, surface and interface morphology, adhesion strengths (including shear strength and pull-off strength), surface roughness, wettings, color intensity, and thermal insulation of the prepared EL and EL/blends were investigated. A scanning electron microscopy (SEM) investigation confirmed filler dispersion and adhesion between the blends, and coated HDF wood, or Al. The developed EL/AG blend had a pull-off strength of 144±5 and 102±3 MPa and a shear strength of 771±11, and 52±3 N with HDF wood and Al substrate, respectively. The EL/PVA blend had a maximum surface roughness value 4.57 µm, and its average water contact angle (WCA) was 85.6°. A plasma jet was used to treat the surface roughness and hence the wettability of the pure EL and the EL/blends, for example, plasma treatment decreased the roughness of the EL/AG blend from 4.36 to 3.28 μm. WCA, and hence wettability, was also significantly influenced by plasma treatment, for example, plasma treatment decreased the WCA of the pure EL from 71.7±0.4° to 30.7±0.7°. The lightness value of the EL/blends was less than that of the pure EL, indicating that (the color adhesives have darkened). Similarly, the yellowness-blueness and redness-greenness values of the EL/blends were greater than those of the pure EL,( rendering the blended adhesives more reddish and bluish). The EL/AG blend was found to have a minimum thermal conductivity (of 0.27 W/m.K), indicating maximum insulation.

Application of coal mining waste in civil and road construction

Aim: This study analyzes the potential for processing coal mining waste in civil and road construction. Materials and Methods. The research focused on rock dumps from eight mines in the Lugansk People’s Republic. According to current methods, samples of dump rock were collected and analyzed in the laboratory for various properties, including Al2O3 content (up to 22%), total sulfur (up to 4%) in rock samples of varying degrees of metamorphism, indicators of its plasticity, and radiation characteristics (up to 220 Bq/kg). Results. This study addresses the processing of rock dumps from coal mines in the Lugansk People’s Republic as a source of raw materials for building materials. A brief analysis of existing methods for obtaining various building materials from waste rocks was carried out. The laboratory tests on waste rock samples from several mines demonstrated their potential use in civil, industrial, and road construction. Conclusion. The research provides a detailed analysis of various indicators and properties of coal mining waste in the Lugansk People’s Republic, including specific effective activity and evaporation coefficient. Findings suggest that the waste rock can be effectively used as raw material in the construction industry, supporting the production of materials for industrial, civil, and road construction.

Study of the kinetics and mechanisms of rare earth elements leaching from end-of-life NdFeB magnets through Hydro-Nd process

With the growing demand for REEs in numerous high-tech and energy transition-related applications, recycling these elements from secondary sources, mainly from end-of-life permanent magnets, has become crucial for responsible sourcing of raw materials from a circular economy. To date, numerous processes have been developed and optimized to allow this recovery to be sustainable from both an economic and environmental point of view. In this context, hydrometallurgy is one of the most promising avenues. Through an innovative hydrometallurgical process (Hydro-Nd), this research investigated the kinetics and mechanisms involved in leaching REEs from end-of-life permanent magnets. This process involves the use of citric acid in the leaching phase. Through systematic experimentation and analysis, the article elucidates key factors influencing leaching kinetics, providing insight into critical mechanisms of the process. In particular, ANOVA was used to study the influence of important factors (temperature, particle size, and agitation) on the recovery yields of the elements of interest. The shrinking core model studied the leaching mechanisms to identify a possible rate-determining step. Thanks to the results obtained, the Arrhenius parameters were estimated for the different heterogeneous reactions involved in the process, and the trend of the time constants versus the average diameter of the solid particles was identified. Also, the results showed that 100 % of Nd, Fe, Dy, B, and Pr from small PM particles (0–40 µm) in 4 h and more than 90 % of the mentioned metals from large particles (1000–1700 µm) within 5 h of leaching time were dissolved by citric acid solution. This research not only contributes to the development of an even more sustainable rare earth recovery process thanks to the optimization of several factors but also clarifies fundamental aspects of leaching kinetics and mechanisms, paving the way for future advances in the recovery of REEs from different sources.

Essential Oil and Waste Hydrosol of Ocimum Tenuiflorum L.: A Low-Cost Raw Material Source of Eugenol, Botanical Pesticides, and Therapeutic Potentiality.

In this study, essential oils and waste hydrosols of leaves of Ocimum tenuiflorum in four different geographical locations were extracted by hydrodistillation method and using gas chromatography/mass spectrometry (GC/MS) for chemical composition analysis. All four essential oil samples contained the main components (E)-β-caryophyllene (27.8-49.0 %), trans-β-elemene (20.3-37.1 %) and eugenol (9.0-44.0 %). Three of the four hydrosol samples had eugenol in absolute content (94.5-98.6 %), while the remaining hydrosol sample had two main components, elemicin (77.8 %) and eugenol (14.2 %). Essential oils and hydrosols demonstrated larvicidal activities against four important disease-transmitting mosquito species including Aedes aegypti, Aedes albopictus, Culex quinquefasciatus, and Culex fuscocephala with 24-h LC50 values in the range 15.42-56.01 μg/mL and 53.88-97.80 μg/mL for the essential oils and the hydrosols, respectively. Essential oils and hydrosols strongly inhibited the acetylcholinesterase (AChE) enzyme of electric eels with IC50 values in the range of 25.35-107.19 μg/mL. Microemulsion (ME) can be considered as a sustainable pesticide formulation over 300 days and has improved larvicidal activity compared to free essential oil. The O. tenuiflorum in Vietnam can be considered a low-cost source of eugenol, botanical pesticides that control disease-transmitting mosquitoes, as well as having therapeutic potential to be further investigated.

Strategic decision-making for sustainable production and distribution in automotive industry: a machine learning enabled dynamic multi-objective optimisation

ABSTRACT Over the last decade, numerous researchers have disclosed that major automotive companies do not conform to regulatory or societal expectations regarding their environmental and social performances. This paper explores the dynamic capabilities of production distribution within the sustainability practices of automotive industries. It offers insights to better grasp and articulate the environmental, economic, and social dimensions of sustainable supply chains. The research framework encloses all supply chain phases, from raw material sourcing to retailing finished products. Three conflicting objective functions are identified: social advantages maximisation, cost minimisation, and emission minimisation. Specifically, the study tackles a dynamic multi-objective optimisation model where each automobile type faces a series of dynamic demands. The dynamic nature of the problem poses significant challenges to conventional evolutionary algorithms for detecting the optimal solutions over time. Therefore, we introduce an interconnected prediction-based dynamic non-dominated sorting algorithm (ICP-DNSGA-II). Finally, extensive computational experiments are conducted to assess the effectiveness of this holistic approach. The findings offer valuable insights for automotive industry stakeholders and policymakers, illustrating its potential to enhance operational efficiency and sustainability performance across the supply chain. Most importantly, this paper proposes an automated decision-making approach to generate optimal solutions with dynamic changes in market demands.

Evaluating the vulnerability of forestry supply chains through fuzzy cognitive map

Recognizing the significant role of the supply chain in economic activity, it is crucial to address its vulnerability areas. This research focuses on the forestry industry, where obtaining and maintaining the primary raw material source is notably more challenging compared to other supply chains. The primary objective of this study is to analyze vulnerability factors specific to the forestry supply chain (FSC) by modeling their interactions and potential influences on each other. Initially, relevant factors were identified through a comprehensive literature review, encompassing vulnerabilities both general supply chain and pertinent to forestry industry such as natural disruptions. Then, using fuzzy cognitive map (FCM), the relationships between these factors were modeled and simulated. An influence map was constructed based on expert opinions, facilitated by triangular fuzzy numbers to express expert judgments accurately. FCM simulations were conducted to analyze the effects of vulnerability factors of FSC on one another across three sustainability-themed scenarios: economically related vulnerabilities, socially related vulnerabilities, and environmentally related vulnerabilities. This research is significant for stakeholders in the forestry industry as it elucidates the vulnerability factors within the forestry supply chain and demonstrates how different vulnerabilities can influence one another.

Thermal Catalytic Production of Potassium Humate Fertilizer from Tobacco Straw and Its Performance in Wheat Hydroponics

Production of artificial humic acid (AHA) from waste biomass will contribute to environmental protection and agricultural productivity. However, there is still a lack of a faster, more efficient and eco-friendly way for sustainable production. In this study, potassium humate was prepared from agricultural waste tobacco straw by thermal catalysis using environmentally friendly Fe2O3 as a catalyst. The yield of potassium humate was successfully increased to 68.77 %. In the present study, using characterization methods such as TG-DTG and UV, it was found that the potassium humate prepared from tobacco straw had lower aromaticity, smaller molecular weight, as well as better solubility and better quality. In addition, the effect of potassium humate fertilizer on wheat biomass was also investigated in this experiment by wheat hydroponics. The results showed that the germination rate of wheat increased by 17 % and the fresh and dry weights increased by 6.94 % and 19.31 %, respectively, with the addition of potassium humate prepared with iron catalyst. This study provides a green and simple technology for the resourceful utilization of tobacco straw to produce high value-added potassium humate, and enriches the source of raw materials for potassium humate, expanding its application in the field of crop growth.

STATE AND PROSPECTS OF THE DEVELOPMENT OF UKRAINE'S BUILDING INDUSTRY IN THE CONDITIONS OF THE ECONOMIC CRISIS CAUSED BY THE FULL-SCALE AGGRESSION OF THE RUSSIA, FROM THE POINT OF VIEW OF ECONOMIC CYCLICITY

The article is dedicated to examining the specific manifestations of economic cyclicality in Ukraine's building materials industry under martial law conditions. The analysis reveals that the full-scale war has led to the destruction of approximately 20% of enterprises, while others have experienced significant declines in production volumes, market access, raw material sources, and human resources. The features of war-induced economic crises are compared with cyclical overproduction crises, showing that military actions immediately push the economy into a recession phase. However, recovery may commence even before the end of hostilities due to the economy reaching the trough of the economic cycle.The article explores various approaches to defining and understanding the concept of "economic crisis," highlighting the importance of identifying its causes and characteristics. Key factors influencing the transition between different phases of economic cycles—recession, depression, recovery, and expansion—are identified. It is noted that the moments of phase transition are critical to economic development, as they represent the shift from quantitative changes in one phase to qualitative changes in the next.The dynamics of real estate prices are analyzed as one of the key indicators signaling the onset of the recovery phase. Additionally, the article formulates the components of a development strategy for Ukraine’s construction sector during the recovery period, taking into account the consequences of the war. These components include the localization of building materials production, improving housing comfort, ensuring the environmental sustainability of building materials, conserving resources in their production (particularly energy), involving foreign aid in the reconstruction process, and recycling demolition waste into building materials. It is determined that the future development of the construction industry must also address the issue of effectively insulating protective structures and bomb shelters with eco-friendly materials, necessitating further development of domestic building materials that meet the urgent demands of wartime. The article concludes with the prospect of utilizing hemp-lime building materials in the reconstruction process, as they fully align with the proposed development strategy

Natural Rubber Latex Wastes from Balloon Production as Valuable Source of Raw Material: Processing, Physico-Mechanical Properties, and Structure

This study explores the potential for recycling natural rubber (NR) latex waste from balloon production through the devulcanization and revulcanization processes. The mechanical devulcanization of colored latex balloon waste was conducted, followed by revulcanization using a sulfur-based system. The reclaimed rubber’s properties, including crosslink density, tensile strength, and abrasion resistance, were compared with those of virgin NR. The results demonstrate that the reclaimed rubber maintains a crosslink density close to that of virgin NR. Hardness and abrasion resistance were comparable, indicating successful material recovery. Structural analyses, including FTIR and SEM microscopy, revealed that the devulcanization process effectively allowed for successful revulcanization. This study concludes that NR latex waste can be effectively recycled and reused in rubber composite formulations, offering a sustainable approach to waste management in the rubber industry and contributing to developing eco-friendly materials. In the context of this research, integrating advanced chemical and physical methods, such as solubility parameter calculations and enhanced devulcanization techniques, could further optimize the devulcanization process. These methods quantitatively enhance the efficiency of material recovery, offering a path to more sustainable recycling practices. The findings suggest that combining such advanced methodologies could significantly improve recycled NR latex’s overall performance and applicability in industrial applications.

Potential uses of silkworm pupae (Bombyx mori L.) in food, feed, and other industries: a systematic review.

The increasing pressures imposed on ecosystems by the growing needs of the human population are stimulus for research into innovative and unconventional sources of raw materials for different industries. This systematic review was carried out to investigate the available literature on the possible industrial uses of silkworm (Bombyx mori L.) pupae, a residue of silk production. The review was conducted using an adapted version of PRISMA. After a screening process, 105 articles were obtained and subjected to a detailed quantitative and qualitative analysis. It was found that in the last decade there has been a significant increase in the number of papers devoted to the study of the potential use of silkworm pupae in different applications, with a significantly higher number in the last three years of the scope of this review, indicating a growing interest in the subject. From the analysis of the information collected, promising uses in human and animal food, such as fish, mammalian, poultry, swine and companion animals, as well as potential uses for the pharmaceutical industry, were identified. The evaluated research identified compounds with antioxidant activity and important contents of unsaturated fatty acids, which are related to beneficial effects on cardiovascular health, diabetes control, reduction of the risk of developing certain types of cancer and inflammatory activity, among other benefits. One of the most relevant findings is that many studies report a significant concentration of α-linolenic acid in silkworm pupae oil, which is attributed with anticancer, anti-inflammatory, antioxidant, anti-obesity and neuroprotective properties, among others.

Pyrolysis combined with KOH activation to turn waste apple pruning branches into high performance electrode materials with multiple energy storage functions

In this paper, porous activated carbon is successfully prepared from waste apple pruning branches (PGZ), which demonstrates an ultra-high specific capacity of 505 F g −1 at a current density of 1 A g −1 with excellent rate performance (215 F g −1 at 50 A g−1). The assembled supercapacitor also exhibits excellent specific capacitance of 320 F g −1 (at 0.5 A g−1) and 160 F g −1 (at 20 A g−1), with a high energy density of 12.03 Wh kg −1 at a power density of 250.45 W kg −1 in 6 M KOH. In 1 M Na2SO 4 and 1 M Et4 NBF4/AC electrolytes, high energy densities of 18.8 Wh kg −1 and 44.1 Wh kg −1 could be achieved. It also exhibits high reversible lithium storage capacity of 636.2 mAh g −1 at 0.2 C and retains 390 mAh g −1 after 1000 cycles. Even at 0.8 C, the storage capacity is still as high as 327 mAh g −1, with 282 mAh g −1 retained after 1000 cycles. These excellent electrochemical properties are attributed to the hierarchical porous structure of the sample prepared under the optimum conditions. The large pores in the hierarchical structure will lead to high-speed capacitive properties due to their low ion transport resistance while the small mesopore and micropore provide a large electrode and electrolyte interface, which can facilitate charge transfer reaction. These outstanding performances highlights the first example of using waste apple pruning branches as a sustainable source of raw materials for the preparation of high value-added porous carbon materials with multiple energy storage functions.

Copper and nickel hexacyanoferrates/carbon nanotube nanocomposites thin films as high-performance light cathode materials for aqueous sodium-ion batteries

Aqueous rechargeable Na-ion batteries are gaining popularity as an attractive alternative for energy storage systems due to their low cost, wide range of raw material sources, non-flammability, and ultrahigh ionic conductivity. Currently, Because of their three-dimensional open structure, high specific capacity, and inexpensive cost, Prussian blue analogues are being investigated as electrode materials for electrochemistry. In this work, we present an innovative strategy to create novel two-component nanoarchitected thin films that exhibit exceptional performance as cathodes in aqueous sodium-ion batteries (SIBs). By leveraging the versatility of the liquid-liquid interfacial method, we have prepared two distinct transparent nanocomposite films composed of carbon nanotubes and either copper or nickel hexacyanoferrate nanoparticles. The results show that the NiHCF/CNT and CuHCF/CNT deliver a high specific capacity of 152 mA h g−1 and 135 mA h g−1, respectively, at a high current density of 1 A g−1. Moreover, the cells (rGO//NiHCF and rGO//CuHCF) show that the energy density of the battery can reach up to 7.75 Wh kg−1 at a power density of 27.92 W kg−1 for rGO//NiHCF/CNT, while rGO//CuHCF/CNT showed an energy density of 3.67 Wh kg−1 at a power density of 13.21 W kg−1. The results demonstrate that NiHCF/CNT and CuHCF/CNT nanocomposite films provide new insight into the design of high-performance PBA cathodes.

Exploring grape pomace extracts for the formulation of new bioactive multifunctional chitosan/alginate-based hydrogels for wound healing applications

Chronic wounds incidence is increasing and affects millions of people around the world, causing great psychological and socio-economic impacts. However, treatments that can effectively promote wound healing are still lacking. In this study, grape pomace (GP), the main residue from winemaking production was explored as a source of high added-value raw material directed for the topical treatment of Staphylococcus aureus chronic wound infections. Crude GP extracts (composed of stalks or a skin and seeds mixture–from red and white grape varieties) obtained using a modified solid-liquid extraction (water, ethanol, and acetone solvents) were evaluated for their antioxidant capacity (ABTS and DPPH assays), as well as the richness of phenolic compounds (total phenolic content-TPC, total flavonoid content-TFC, and HPLC-DAD assays). The GP extracts with the most favorable results were incorporated in a chitosan-alginate hydrogel (cross-linked with glutaraldehyde and calcium chloride), characterized (swelling, degradation, and release properties), and tested for its bioactivity (antioxidant and antimicrobial potential). TPC and TFC were higher in red GP extracts, as confirmed by the HPLC analysis, indicating a greater diversity of compounds in these extracts. Ethanolic white GP extracts (from skin-seeds mixture) showed the highest extraction yield and antioxidant activity. Their incorporation into the chitosan-alginate hydrogel improved its swelling and antimicrobial properties (total cytoplasmic membranes disruption and culturability reduction). A biomaterial with high swelling capacity and antibacterial activity against S. aureus was obtained, which can potentially promote wound healing by exudate absorption and infection clearance while promoting valorization of by-products and stimulating a circular economy.

Optimization of preparation conditions for β-chitosan derived from diatom biomanufacturing using response surface methodology

Chitosan is a polymeric polysaccharide with widely application. At present, commercialized chitosan obtained by deacetylating chitin with acid-alkali method. The homogeneity of the molecular weight of chitosan is difficult to adjust due to the low homogeneity of chitosan itself and the degradation effect of the extraction process. And the single source of raw material has limited the further development of chitosan. In this study, diatoms were used as the source of chitosan extraction through alkalization freeze-thaw method, and response surface methodology was also used to optimize the best preparation conditions of diatom chitosan. The extracted chitosan from diatom was β-type chitosan with low molecular weight, great homogeneity. Diatom chitosan was able to reduce blood loss and clotting time >30 % in vivo experiment compared to control. The hemolysis rate of diatom chitosan was lower than 1 %, and the survival rate was higher than 95 % when co-cultured with L929 cells. Diatom chitosan with 0.005 % could inhibit E. coli and S. aureus by >90 %. Considering the large-scale cultivation properties of diatom, the extraction of diatom chitosan based on alkalization freeze-thaw method will provide a viable solution for obtaining β-chitosan with homogeneity on a large scale.