Environmentally Friendly Method for the Separation of Cellulose from Steam-Exploded Rice Straw and Its High-Value Applications

Separation of cellulose from agricultural straw is one of the key bottlenecks hindering the application of such kind of biomass resources. In this chapter, we provide three environmental-friendly ways for separation of cellulose from agricultural straw pretreated with steam explosion, which include delignification with recyclable water-polar aprotic organic solvent, selective bio-degradation of the lignin component, and extraction of cellulose with imidazolium-based ionic liquids from the steam-exploded rice straw. The isolated rice straw celluloses have been adopted as an enhancement for all-cellulose composites (ACCs) and cellulose/cement composites. Ultra-high tensile strength (650.2 MPa) can be achieved for the ACCs containing the activated straw cellulose fiber (A-SCF). The cellulose/cement composites show a significant promotion in the flexural strength and fracture toughness. The new nonderivative solvent for cellulose, tetrabutylammonium hydroxide (TBAH) aqueous solution with urea as additives has been proved to be manipulable for dissolving cellulose

A Coal Seam Thickness Prediction Model Based on CPSAC and WOA–LS-SVM: A Case Study on the ZJ Mine in the Huainan Coalfield

The precise prediction of coal seam thickness in operating mines is crucial for the construction of transparent mines. Geological borehole data or a small amount of seismic information is frequently used in traditional coal seam thickness prediction methods; however, these methods have poor precision. In this study, we introduced a model for predicting coal seam thickness based on the comprehensive preference for seismic attribute combination (CPSAC) and the least squares support vector machine (LS-SVM) optimized by the whale optimization algorithm (WOA). We used the CPSAC to modify the mass disturbed data in the seismic attribute data to predict the coal seam thickness. To achieve this the sample size was reduced by optimizing the seismic attribute combinations, and the modified attribute data was entered into the LS-SVM., Furthermore, to create an accurate prediction model for coal thickness, we employed the WOA to determine the optimal penalty coefficient and kernel coefficient of the LS-SVM. An empirical case study was conducted in the northeast mining area of the ZJ mine in the Huainan coalfield. The coal thickness of two mining faces in this research area were estimated and compared, demonstrating the proposed method’s high prediction accuracy. The proposed method has guiding implications for developing an accurate mining geological model and facilitating the accurate use of coal resources

A Review on the Effects of Pretreatment and Process Parameters on Properties of Pellets

The development and utilization of biomass can not only address the demand for low-carbon energy and reduce environmental pollution, but can also facilitate the achievement of carbon neutrality. However, there are many factors justifying the case for low utilization of agricultural residues. These factors could be well controlled by producing top-quality pellets. Production of pellets is generally accompanied by the problems of high energy consumption and serious mold wearing. To eliminate these deficiencies, pretreatment has attracted scholars’ attention. In this review, the effects of four pretreatments on the properties of pellets were assessed. Thermal pretreatment can improve the hydrophobicity of pellets, and optimize their properties, while degradation of diverse extractives is noteworthy. Hydrothermal pretreatment improves the physical properties of pellets, through the increase of polar functional groups on the surface of the biomass. Ultrasonic vibration-assisted (UV-A) pelleting produces pellets under low pressure without a heating process; however, it is still not applied to large-scale production. Supercritical fluid extraction can achieve the graded utilization of extracts and bioactive substances in biomass, and the residues can be subsequently utilized as pellet feedstock. Mild hydrothermal treatment is a promising approach to improving the quality of agricultural pellets. Additionally, the effects of process parameters on the physical and chemical properties of pellets should be systematically analyzed

A Review on the Effects of Pretreatment and Process Parameters on Properties of Pellets

The development and utilization of biomass can not only address the demand for low-carbon energy and reduce environmental pollution, but can also facilitate the achievement of carbon neutrality. However, there are many factors justifying the case for low utilization of agricultural residues. These factors could be well controlled by producing top-quality pellets. Production of pellets is generally accompanied by the problems of high energy consumption and serious mold wearing. To eliminate these deficiencies, pretreatment has attracted scholars’ attention. In this review, the effects of four pretreatments on the properties of pellets were assessed. Thermal pretreatment can improve the hydrophobicity of pellets, and optimize their properties, while degradation of diverse extractives is noteworthy. Hydrothermal pretreatment improves the physical properties of pellets, through the increase of polar functional groups on the surface of the biomass. Ultrasonic vibration-assisted (UV-A) pelleting produces pellets under low pressure without a heating process; however, it is still not applied to large-scale production. Supercritical fluid extraction can achieve the graded utilization of extracts and bioactive substances in biomass, and the residues can be subsequently utilized as pellet feedstock. Mild hydrothermal treatment is a promising approach to improving the quality of agricultural pellets. Additionally, the effects of process parameters on the physical and chemical properties of pellets should be systematically analyzed

Intercalation Polymerization Approach for Preparing Graphene/Polymer Composites

The rapid development of society has promoted increasing demand for various polymer materials. A large variety of efforts have been applied in order for graphene strengthened polymer composites to satisfy different requirements. Graphene/polymer composites synthesized by traditional strategies display some striking defects, like weak interfacial interaction and agglomeration of graphene, leading to poor improvement in performance. Furthermore, the creation of pre-prepared graphene while being necessary always involves troublesome processes. Among the various preparation strategies, an appealing approach relies on intercalation and polymerization in the interlayer of graphite and has attracted researchers’ attention due to its reliable, fast and simple synthesis. In this review, we introduce an intercalation polymerization strategy to graphene/polymer composites by the intercalation of molecules/ions into graphite interlayers, as well as subsequent polymerization. The key point for regulating intercalation polymerization is tuning the structure of graphite and intercalants for better interaction. Potential applications of the resulting graphene/polymer composites, including electrical conductivity, electromagnetic absorption, mechanical properties and thermal conductivity, are also reviewed. Furthermore, the shortcomings, challenges and prospects of intercalation polymerization are discussed, which will be helpful to researchers working in related fields

Defects Induced Room Temperature Ferromagnetism in ZnO Thin Films

Polycrystalline ZnO thin films are prepared by the co-sputtering method under different oxygen partial pressures. Films deposited in pure argon gas exhibit ferromagnetism, whereas other films deposited under different oxygen partial pressures are diamagnetism. XPS results show the presence of Zn interstitial and oxygen vacancy in all of samples. Further analysis indicates that Zn interstitial may play an important role in triggering magnetic order on the undoped ZnO thin films by inducing an alteration of electronic configuration

Ectopic multiple digit replantation salvage of hand torsion injury following anterolateral thigh perforator flap coverage

Retrieval of four finger injury at proximal stump amputation with segmental injury along with soft tissue defect and impending compartment syndrome continues to be challenge for the surgeon. Immediate transplant considering temporary ectopic foster as a practical option in special case. We describe temporary ectopic finger implant for crush injury at Metacarpophalangeal (MCP level) with hand torsion along with forearm compartment was fostered to Dorsum of the foot. The torsion fingers was temporary fixed with mini external fixator for stabilization as salvage, ALT free flap was used to cover soft tissue defect of the hand. Replantation of survived figure was performed using the long pedicle to anatomical site without crushing the MCP joint to allow for later tendon transfer for finger. Satisfactory function regained with no foster site (foot) complication like pain or disability. The author validated ectopic foster for amputee as and procedure of choice for salvage of extremity under special circumstances

Remarkable Improvement in the Mechanical Properties of Epoxy Composites Achieved by a Small Amount of Modified Helical Carbon Nanotubes

Helical carbon nanotubes (HCNTs) were functionalized to fabricate HCNT/epoxy composites. Acid oxidation and a silane coupling agent, glycidoxypropyltrimethoxysilane (KH560), were used to modify the HCNTs. Remarkably, the flexural strength and the flexural strain were enhanced by 72.0% and 325.0%, respectively, compared to pure epoxy after adding a small amount of the KH560 modified HCNTs (K-HCNTs). Simultaneously, the tensile strength and Young’s modulus of K-HCNTs/epoxy composites were 51.3% and 270.9% higher than those of pure epoxy. It is found that the presence of silane molecules improved the dispersion of HCNTs in epoxy and the interfacial interaction. Moreover, it has been found that the mechanically interlocking effect from the helical shape of HCNTs also contributes to the improved mechanical properties of epoxy composites, compared to their straight multi-walled carbon nanotube (MWCNT) counterparts. This work provides a low-cost and efficient approach to strengthen and toughen epoxy composites