Development of cost-effective cellulose-based bilayer hybrid composite membranes for CO2 separation in biogas purification.

CO2 is the main pollutant in biogas, reducing its calorific value. Among various technological methods to eliminate carbon dioxide from biogas, membrane separation technology stands out for large-scale industrial biogas purification due to its advantages. The selection of membrane material and preparation process are key factors in membrane separation technology. In this study, a premixing process was initially used to blend different masses of packed molecular sieves TS-1 (or ZSM-5) and cellulose derivatives (ethyl cellulose, cellulose acetate) separately. These mixtures were then coated onto porous PVDF substrates using a coating process to create various bilayer hybrid composite membranes. Among these, PVDF/EC-ZSM-5 (containing 15 % ZSM-5) bilayer hybrid composite membrane is the most fitting. For CO2/CH4 gas mixtures, the gas selectivity of this membrane surpassed Robeson's 1991 standard line (the CO2 permeability was 597.48 Barrer, and the CO2/CH4 selectivity was 9.14). Overall, this composite membrane, made for the first time from PVDF, ZSM-5, and EC, is expected to be a promising CO2 selective separation membrane material for biogas purification in large-scale industrial processes due to its simple production process.

Research progress in the preparation of lignin-based carbon nanofibers for supercapacitors using electrospinning technology: A review.

With the development of renewable energy technologies, the demand for efficient energy storage systems is growing. Supercapacitors have attracted considerable attention as efficient electrical energy storage devices because of their excellent power density, fast charging and discharging capabilities, and long cycle life. Carbon nanofibers are widely used as electrode materials in supercapacitors because of their excellent mechanical properties, electrical conductivity, and light weight. Although environmental factors are increasingly driving the application of circular economy concepts in materials science, lignin is an underutilized but promising environmentally benign electrode material for supercapacitors. Lignin-based carbon nanofibers are ideal for preparing high-performance supercapacitor electrode materials owing to their unique chemical stability, abundance, and environmental friendliness. Electrospinning is a well-known technique for producing large quantities of uniform lignin-based nanofibers, and is the simplest method for the large-scale production of lignin-based carbon nanofibers with specific diameters. This paper reviews the latest research progress in the preparation of lignin-based carbon nanofibers using the electrospinning technology, discusses the prospects of their application in supercapacitors, and analyzes the current challenges and future development directions. This is expected to have an enlightening effect on subsequent research.

Advanced biomass-based Janus materials: Classification, preparation and application: A review.

In contrast to conventional particles characterized by isotropic surfaces, Janus particles possess anisotropic surfaces, resulting in unique physicochemical properties and functional attributes. In recent times, there has been a surge in interest regarding the synthesis of Janus particles using biological macromolecules. Various synthesis techniques have been developed for the fabrication of Janus materials derived from biomass. These methods include electrospinning, freeze-drying, secondary casting film formation, self-assembly technology, and other approaches. In the realm of Janus composite materials, those derived from biomass have found extensive applications in diverse domains including oil-water separation, sensors, photocatalysis, and medical materials. This article provides a systematic introduction to the classification of Janus materials, with a specific focus on various types of biomass-based Janus materials (mainly cellulose-based Janus materials, lignin-based Janus materials and protein-based Janus materials) and the methods used for their preparation. This work will not only deepen the understanding of biomass-based Janus materials, but also contribute to the development of new methods for designing biomass-based Janus structures to optimize biomass utilization.

Novel Lignin-Cellulose-Based Carbon Nanofibers as High-Performance Supercapacitors.

In this work, a simple phosphating process was proposed to modify cellulose-acetate (CA) and lignin for a novel energy storage precursor material. The prepared precursor fibers exhibited good thermal stability of lignin and flexibility of CA. Subsequently, the precursor fibers undergo a short preoxidation and carbonization treatment process to obtain the biomass-based carbon fibers (CFs) with complete fibrous morphology, uniform fiber diameter, high surface areas, good flexibility, and excellent power storage capacity. The specific capacitance of 346.6 F/g was obtained by using CFs-5 (prepared with 40% H3PO4 content) as a supercapacitor. Simultaneously, the biomass-based CF supercapacitor device delivers a high-energy density of 31.5 Wh/kg at the power density of 400 W/kg. These results indicate that the introduction of H3PO4 can effectively reduce the energy consumption of the preoxidation treatment process for the preparation of the biomass-based CFs, while increasing the energy storage properties significantly. This novel strategy showed a successful route for the preparation of high-quality and low-consumption biomass-based CFs.

Novel porous oil-water separation material with super-hydrophobicity and super-oleophilicity prepared from beeswax, lignin, and cotton.

The traditional fluorinated porous material with super-hydrophobicity and super-oleophilicity is an effective strategy for oil-water separation. However, in recent years, fluorinated materials have been classified as "Emerging Environmental Pollutants" by U. S. Environmental Protection Agency because of difficult degradation and bio-accumulation. It is unacceptable to introduce new pollutants while solving environmental disasters. Therefore, it is great requirement to explore a low-cost, environmentally friendly, and renewable technique for the fabrication of novel porous materials with super-hydrophobicity and super-oleophilicity to separate oil-water mixtures. In this work, renewable beeswax, lignin, and cotton have been chosen to prepare the biomass-based porous materials with super-hydrophobicity and super-oleophilicity for oil-water separation. The mixture of beeswax and lignin is modified on the surface of cotton to obtain the biomass-based porous materials with super-hydrophobicity and super-oleophilicity. The beeswax and lignin provide low surface energy and micro/nanoscale structures, respectively. The introduction of lignin effectively improves the thermal stability of the porous materials. The apparent contact angle still remains to be above 150° after a long-time heating. The porous materials effectively separate oil-water mixtures and have good absorption effect for heavy oil (density greater than water). Moreover, the porous materials are easily recyclable after reactivation. This strategy of preparing oil-water separation materials from renewable natural polymers not only helps to clean the environment, but also helps to recover valuable oil.

Novel lignin-chitosan-PVA composite hydrogel for wound dressing.

Although PVA-chitosan composite hydrogel has excellent biocompatibility and antibacterial ability, its poor mechanical strength limits its application for wound dressings. Furthermore, PVA-chitosan composite hydrogel cannot satisfy the requirements of wound dressing as an environmental conditioner to accelerate wound healing. In this work, a novel lignin-chitosan-PVA composite hydrogel was prepared as wound dressing. The introduction of lignin effectively improved the mechanical strength (tensile stress is up to 46.87 MPa), protein adsorption capacity, and wound environmental regulation ability of the hydrogel. In a murine wound model, the lignin-chitosan-PVA composite hydrogel significantly accelerated wound healing. The developed hydrogel provides new opportunities for highly efficient skin wound care and management.

Functional food packaging for reducing residual liquid food: Thermo-resistant edible super-hydrophobic coating from coffee and beeswax.

Edible super-hydrophobic coatings have attracted great attentions as they can avoid the waste of liquid foods, such as honey and milk, adhered to the inside of containers. However, the poor thermal stabilities of edible super-hydrophobic coatings restrict their applications. In this work, a thermo-resistant edible super-hydrophobic coating has been fabricated using beeswax and coffee, which are approved by U.S. Food and Drug Administration. This coating surface has the similar micro/nanoscale structure to that of the leaf surface. A variety of liquid foods can freely roll on this coating surface in spherical. This special wetting property effectively reduces the residue of liquid foods, when they are poured out of the containers. With the introduction of coffee lignin, the thermal stability and adhesive force of the coating increases significantly. The apparent contact angle of this coating can remain to be above 150° after a long-time heating and flushing. This thermo-resistant edible super-hydrophobic coating can solve the problem that original edible super-hydrophobic coating is not resistant to high temperature, and has a broad application prospect in the field of functional food packaging.

Research on meteorological conditions and their related diseases in Hefei, China.

Synchronous meteorological data from 9688 cases of patients in the Second People's Hospital of HeFei in AnHui province, China, who suffered from hypertension, cerebrovascular disease, cardiopathy, upper respiratory tract infection, and chronic bronchitis, were analyzed. The results show that there are five kinds of weather processes that greatly affect these diseases. This study provides evidence of the importance of enhancing the people's knowledge of preventing disease and improving the medical- weather service.

Optimal competitive hopfield network with stochastic dynamics for maximum cut problem.

In this paper, introducing stochastic dynamics into an optimal competitive Hopfield network model (OCHOM), we propose a new algorithm that permits temporary energy increases which helps the OCHOM escape from local minima. The goal of the maximum cut problem, which is an NP-complete problem, is to partition the node set of an undirected graph into two parts in order to maximize the cardinality of the set of edges cut by the partition. The problem has many important applications including the design of VLSI circuits and design of communication networks. Recently, Galán-Marín et al. proposed the OCHOM, which can guarantee convergence to a global/local minimum of the energy function, and performs better than the other competitive neural approaches. However, the OCHOM has no mechanism to escape from local minima. The proposed algorithm introduces stochastic dynamics which helps the OCHOM escape from local minima, and it is applied to the maximum cut problem. A number of instances have been simulated to verify the proposed algorithm.