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The treatment of bone defects caused by disease or accidents through the use of implants presents significant clinical challenges. After clinical implantation, these materials attract and accumulate bacteria and hinder the integration of the implant with bone tissue due to the lack of osteoinductive properties, both of which can cause postoperative infection and even lead to the eventual failure of the operation. This work successfully prepared a novel biomaterial coating with multiple antibacterial mechanisms for potent and durable and osteoinductive biological tissue replacement by pulsed PED (electrochemical deposition). By effectively regulating PPy (polypyrrole), the uniform composite coating achieved sound physiological stability. Furthermore, the photothermal analysis showcased exceptional potent photothermal antibacterial activity. The antibacterial assessments revealed a bacterial eradication rate of 100% for the PPy@Cu/PD composite coating following a 24 h incubation. Upon the introduction of NIR (near-infrared) irradiation, the combined effects of multiple antibacterial mechanisms led to bacterial reduction rates of 99% for E. coli and 98% for S. aureus after a 6 h incubation. Additionally, the successful promotion of osteoblast proliferation was confirmed through the application of the osteoinductive drug PD (pamidronate disodium) on the composite coating's surface. Therefore, the antimicrobial Ti-based coatings with osteoinductive properties and potent and durable antibacterial properties could serve as ideal bone implants.
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One of the most effective strategies for modifying the surface properties of nano-fillers and enhancing their composite characteristics is through polymer grafting. In this study, a coprecipitation method was employed to modify hydroxyapatite (HAP) with epoxidized soybean oleic acid (ESOA), resulting in ESOA-HAP. Subsequently, oligomeric poly(lactic acid) (OPLA) was grafted onto the surface of ESOA-HAP, yielding OPLA-ESOA-HAP. HAP, ESOA-HAP, and OPLA-ESOA-HAP were comprehensively characterized. The results demonstrate the progressive grafting of ESOA and OPLA onto the surface of HAP, resulting in enhanced hydrophobicity and improved dispersity in organic solvent for OPLA-ESOA-HAP compared to HAP. The vitality and adhesion of Wistar rat mesenchymal stem cells (MSCs) were assessed using HAP and modified HAP materials. Following culture with MSCs for 72 h, the OPLA-ESOA-HAP showed an inhibition rate lower than 23.0% at a relatively high concentration (1.0 mg/mL), which is three times lower compared to HAP under similar condition. The cell number for OPLA-ESOA-HAP was 4.5 times higher compared to HAP, indicating its superior biocompatibility. Furthermore, the mechanical properties of the OPLA-ESOA-HAP/PLLA composite almost remained unaltered ever after undergoing two stages of thermal processing involving melt extrusion and inject molding. The increase in the biocompatibility and relatively high mechanical properties render OPLA-ESOA-HAP/PLLA a potential material for the biodegradable fixation system.
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Plant litter decomposition is a natural pathway of heavy metal cycling in soil ecosystems, but the dynamics of heavy metal release during litter decomposition are relatively poorly understood. The purpose of this study was to investigate the effects of species, soil fauna and soil Cd addition on litter decomposition and Cd release dynamics. Therefore, we selected two plants, Solanum nigrum and S. lycopersicum with large differences in Cd accumulation capacity. First, they were enriched with Cd during the growing period and leaf litter was harvested after 6 months of pretreatment. Then, the decomposition of leaf litter was conducted with or without soil Cd and Eisenia fetida through lab pot tests. Our results showed that leaf litter Cd led to a significant decrease in litter decomposition rate (K value), with a maximum decrease of 32.1% in S. nigrum and 30.1% in S. lycopersicum. We observed that the presence of E. fetida significantly increased K value, but the effect was similar in the +leaf Cd treatment and the -leaf Cd treatment, both for S. nigrum and S. lycopersicum. Interestingly, the litter Cd concentration did not decrease during decomposition, but showed an increasing trend, especially for S. nigrum in the +soil Cd treatment. Moreover, the litter Cd remains was higher in the +soil Cd treatment compared to the -soil Cd treatment for both S. nigrum and S. lycopersicum, no matter whether with or without E. fetida. This result suggests that the Cd may be transferred from soil to litter, thus increasing the litter Cd remains. Overall, our study shows that leaf litter Cd slowed down the carbon cycling in ecosystems. In addition, the release of litter Cd has a lag, and the litter has a certain adsorption capacity for soil Cd, which intensifies the harm to the ecology during litter transfer.
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Metais Pesados , Poluentes do Solo , Solanum lycopersicum , Solanum nigrum , Cádmio/análise , Solanum nigrum/metabolismo , Biodegradação Ambiental , Solo , Ecossistema , Poluentes do Solo/análise , Metais Pesados/metabolismo , Folhas de Planta/químicaRESUMO
The poor electrode kinetics and low conductivity of the LiMn0.8 Fe0.2 PO4 cathode seriously impede its practical application. Here, an effective strategy of boron-catalyzed graphitization carbon coating layer is proposed to stabilize the nanostructure and improve the kinetic properties and Li-storage capability of LiMn0.8 Fe0.2 PO4 nanocrystals for rechargeable lithium-ion batteries. The graphite-like BC3 is derived from B-catalyzed graphitization coating layers, which can not only effectively maintain the dynamic stability of the LiMn0.8 Fe0.2 PO4 nanostructure during cycling, but also plays an important role in enhancing the conductivity and Li+ migration kinetics of LiMn0.8 Fe0.2 PO4 @B-C. The optimized LiMn0.8 Fe0.2 PO4 @B-C exhibits the fastest intercalation/deintercalation kinetics, highest electrical conductivity (8.41 × 10-2 S cm-1 ), Li+ diffusion coefficient (6.17 × 10-12 cm2 s-1 ), and Li-storage performance among three comparison samples (B-C0, B-C6, and B-C9). The highly reversible properties and structural stability of LiMn0.8 Fe0.2 PO4 @B-C are further proved by operando XRD analysis. The B-catalyzed graphitization carbon coating strategy is expected to be an effective pathway to overcome the inherent drawbacks of the high-energy density LiMn0.8 Fe0.2 PO4 cathode and to improve other cathode materials with low-conductivity and poor electrode kinetics for rechargeable second batteries.
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Clothing is considered to be an important element of human social activities. With the increasing maturity of 3D printing technology, functional 3D printing technology can realize the perfect combination of clothing and electronic devices while helping smart clothing to achieve specific functions. Furthermore, the application of functional 3D printing technology in clothing not only provides people with the most comfortable and convenient wearing experience, but also completely subverts consumers' perception of traditional clothing. This paper introduced the progress of the application of 3D printing from the aspect of traditional clothing and smart clothing through two mature 3D printing technologies normally used in the field of clothing, and summarized the challenges and prospects of 3D printing technology in the field of smart clothing. Finally, according to the analysis of the gap between 3D-printed clothing and traditionally made clothing due to the material limitations, this paper predicted that the rise in intelligent materials will provide a new prospect for the development of 3D-printed clothing. This paper will provide some references for the application research of 3D printing in the field of smart clothing.
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The rapidly growing Internet of Things (IoT) has brought about great demand for high-performance sensors as well as power supply devices for those sensors. In this respect, the integration of sensors and energy storage devices, or the development of multifunctional devices having both energy storage and sensing properties, is of great interest in the development of compact sensing systems. As a proof of concept, a zinc-ion hybrid supercapacitor (ZHS) based on a double-crosslinked hydrogel electrolyte is developed in this work, which can be employed not only as an energy storage device, but also as a self-powered sensor for human movement and breathing detection. The ZHS delivers a capacitance of 779 F g-1 and an energy density of 0.32 mWh cm-2 at a power density of 0.34 mW cm-2, as well as sensitive resistance response to strain. Our work provides a useful basis for future designs of self-powered sensing devices and function-integrated systems.
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Microplastics exist widely in water environment. The microplastic distribution in sediments can better reflect the long-term microplastic pollution, especially the vertical distribution. However, the vertical microplastic distribution in sediments is diverse and unclear. This paper is the first study on vertical microplastic distribution in estuary sediment of Fuhe River, the main upstream river flowing to Baiyangdian Wetland in the northern China. The typical feature of Fuhe River is that the effluent of municipal wastewater treatment plants is its main water source. Microplastics in 15 sampling sites and different depths (0-50 cm) were examined. Results showed that the microplastic content decreased with the increase of sediment depth, and the highest content was 1049 ± 462 items/kg in the topmost sediment layer (0-5 cm). The particle size of microplastics was smaller in deeper sediment layers. The proportion of colored microplastics in deeper sediment layers was larger than that in shallower layers. Polyethylene (PE) and polypropylene (PP) were the main plastic polymer types in all sediment samples. The spatial distribution characteristics of microplastics in sediments were closely related to human activities, and the microplastic content was higher in the areas with more intense human activities. This study is helpful to understand the detailed distribution characteristics of microplastics in typical rivers in the northern China, and can provide guidance for reducing microplastic pollution.
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Microplásticos , Poluentes Químicos da Água , China , Monitoramento Ambiental , Estuários , Sedimentos Geológicos , Humanos , Plásticos , Rios , Poluentes Químicos da Água/análise , Áreas AlagadasRESUMO
Miniaturized energy storage devices (MESDs) provide future solutions for powering dispersive electronics and small devices. Among them, aqueous zinc ion microbatteries (ZIMBs) are a type of promising MESDs because of their high-capacity Zn anode, safe and green aqueous electrolytes, and good battery performances. Herein, for the first time, a simple and powerful strategy to fabricate flexible ZIMBs based on tailored soft templates is reported, which are patterned by engraving and enables to design the ZIMBs featured with arbitrary shapes and on various substrates. The assembled ZIMBs employing α-MnS as the cathode materials and guar gum gel as the quasi-solid-state electrolyte exhibited very high areal specific capacity of up to 178 µAh cm-2 , a notable areal energy density of 322 µWh cm-2 and power density of 710 µW cm-2 . Footprint areas of the manufactured ZIMBs as small as 40 mm2 can be achieved. The proposed method based on the engraved soft templates provides a practical route for ZIMB and other MESD designs, which is critical for portable and wearable electronics development.
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Rumen liquid is excellent to effectively degrade lignocellulose. In this study, the suitable rice straw load during anaerobic fermentation of rice straw with rumen liquid as inoculum was explored to improve volatile fatty acid (VFA) production. At 10.0% rice straw load, the highest VFA concentration reached 10821.4 mg/L, and acetic acid and propionic acid were the main components. In 10.0% rice straw load system, high concentration of soluble chemical oxygen demand (SCOD) was also observed, and the enzymatic activities at 48 h were higher than those at other rice straw loads. At 10.0% rice straw load, lower diversity and richness of rumen bacteria were found than those at other rice straw loads. Bacteroides, Prevotella, and Ruminococcus were the main rumen bacteria during rice straw degradation, and the rumen bacteria might secret effective lignocellulolytic enzymes to enhance the hydrolysis and acidogenesis of rice straw. The determination of suitable rice straw load will be beneficial to the application of rumen liquid as inoculum in actual production.
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Oryza , Rúmen , Anaerobiose , Animais , Fermentação , Hidrólise , Rúmen/metabolismoRESUMO
Rumen liquid can effectively degrade lignocellulosic biomass, in which rumen microorganisms play an important role. In this study, transformation of bacterial community structure in rumen liquid anaerobic digestion of rice straw was explored. Results showed that rice straw was efficiently hydrolyzed and acidified, and the degradation efficiency of cellulose, hemicellulose and lignin reached 46.2%, 60.4%, and 12.9%, respectively. The concentration of soluble chemical oxygen demand (SCOD) and total volatile fatty acid (VFA) reached 12.9 and 8.04 g L-1. The high-throughput sequencing results showed that structure of rumen bacterial community significantly changed in anaerobic digestion. The Shannon diversity index showed that rumen bacterial diversity decreased by 32.8% on the 5th day of anaerobic digestion. The relative abundance of Prevotella and Fibrobacter significantly increased, while Ruminococcus significantly decreased at the genus level. The Spearman correlation heatmap showed that pH and VFA were the critical factors affecting the rumen bacterial community structure. The function prediction found that rumen bacteria mainly functioned in carbohydrate transport and metabolism, which might contain a large number of lignocellulose degrading enzyme genes. These studies are conducive to the better application of rumen microorganisms in the degradation of lignocellulosic biomass.
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Oryza , Rúmen , Anaerobiose , Animais , Biomassa , Digestão , Ácidos Graxos Voláteis , Lignina/metabolismo , Oryza/metabolismoRESUMO
This review paper focuses on the researches published in 2019 in the field of thermal effects in wastewater and solid waste treatment. The content of this review paper includes five parts: wastewater and sludge treatment, nutrient removal and recovery, membrane technology, heavy metal removal and immobilization, and organic waste utilization. © 2020 Water Environment Federation PRACTITIONER POINTS: Thermal effect plays an important role in treatment of wastewater and sewage sludge. Recovery of nitrogen and phosphorus from wastewater and sewage sludge reduces environmental pollution and offers new products. Temperature improves removal and recovery of heavy metals and organic wastes.
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Metais Pesados , Esgotos , Metais Pesados/análise , Nitrogênio , Fósforo , Eliminação de Resíduos Líquidos , Águas ResiduáriasRESUMO
Rapid development of livestock industry produces large amount of livestock manure rich in nutrients, organic matters, antibiotics, and heavy metals, thus imposes great harms to human and environment, if the manure is not suitably treated. Biological removal and recovery of nutrients from manure as agriculture fertilizer is attractive due to low cost and simple operation. This review offers an overview of recent development in biological nutrient removal and recovery from livestock manure. Livestock manure is divided into solid manure and liquid manure. Composting and anaerobic digestion of solid manure are fully discussed and important parameters are investigated. Then various processes of nutrient removal and recovery from liquid manure are summarized. Brief economic sustainability and eco-environmental effects are carried out. Finally, current challenges and future prospects in this field are analyzed.
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Compostagem , Esterco , Animais , Fertilizantes , Humanos , Gado , NutrientesRESUMO
When dual-chamber microbial fuel cell (MFC) is used to detect biochemical oxygen demand (BOD), dissolved oxygen is traditionally used as cathodic electron acceptor. The detection limit of this MFC-based BOD biosensor is usually lower than 200â¯mg/L. In this paper, the startup of MFC-based BOD biosensor was researched and the external resistor of MFC was optimized. Results showed that the MFC started up with the dissolved oxygen as cathodic electron acceptor within 10â¯d, and the external resistor was optimized as 500â¯Ω to ensure the maximum output power of MFC. Dissolved oxygen and potassium permanganate (KMnO4) were used as cathodic electron acceptor to run MFC for detection of wastewater BOD, and the performances of two kinds of BOD biosensors were compared. The MFC-based BOD biosensor using KMnO4 (10â¯mmol/L) as cathodic electron acceptor exhibited an excellent performance, compared with that using dissolved oxygen. The upper limit of BOD detection was greatly broadened to 500â¯mg/L, the response time was shortened by 50% for artificial wastewater with a BOD of 100â¯mg/L, and the relative error of BOD detection was reduced to less than 10%. The MFC-based BOD biosensor using KMnO4 as cathodic electron acceptor showed a better linear relationship (R2â¯>â¯0.992) between the electric charge and BOD concentration within a BOD range of 25-500â¯mg/L. The MFC-based BOD biosensor using the KMnO4 as cathodic electron acceptor is promising with a better application prospect.
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Fontes de Energia Bioelétrica , Técnicas Biossensoriais , Análise da Demanda Biológica de Oxigênio , Eletrodos , Elétrons , Oxigênio , Permanganato de PotássioRESUMO
This review focuses on the research literature published in 2018 relating to thermal effects in wastewater and solid waste treatment. This review is divided into the following sections: treatment of wastewater and sludge, removal and recovery of nitrogen and phosphorus, reduction and recovery of heavy metals, membrane technology, and treatment and disposal of solid wastes. PRACTITIONER POINTS: Thermal effect plays an important role in the treatment of wastewater and sewage sludge. Recovery of nitrogen and phosphorus from wastewater and sewage sludge offers an excellent feedstock for soil amendment. Increase of treatment temperature facilitates removal and recovery of heavy metals from water and soil environment.
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Metais Pesados , Eliminação de Resíduos Líquidos , Fósforo , Esgotos , Águas ResiduáriasRESUMO
Previous studies have shown that the impurity Li3V2(PO4)3 in LiVPO4F will adversely affect its electrochemical performance. In this work, we show that the crystalline composition of LiVPO4F/C is mainly influenced by the environmental temperature. The content of Li3V2(PO4)3 formed in LiVPO4F/C is 0, 11.84 and 18.75% at environmental temperatures of 10, 20, and 30°C, respectively. For the sample LVPF-30C, the SEM pattern shows a kind of alveolate microstructure and the result of selected area electron diffraction shows two sets of patterns. The LiVPO4F/C cathode without impurity phase Li3V2(PO4)3 was prepared at 10°C. The selected area electron diffraction result proves that the lattice pattern of LiVPO4F is a regular parallelogram. Electrochemical tests show that only one flat plateau around 4.2 V appears in the charge/discharge curve, and the reversible capacity is 140.4 mAh·g-1 at 0.1 C, and 116.3 mAh·g-1 at 5 C. From these analyses, it is reasonable to speculate that synthesizing LiVPO4F/C at a low environmental temperature is a practical strategy to obtain pure crystalline phase and good electrochemical performance.
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A new series of Co80-x-yCrxMoyP14B6 (x=5 y=5; x=5 y=10; x=10 y=10, all values in at.%) bulk metallic glasses (BMGs) with a maximum diameter of 1.5mm has been developed for using them as potential bio-implant materials by a combination of fluxing treatment and J-quenching technique. The performance of the present Co-based BMGs in biomedical implant applications was investigated as compared to the CoCrMo biomedical alloy (ASTM F75) and 316L stainless steel (316L SS). The corrosion behavior of the samples was investigated in both Hank's solution (pH=7.4) and artificial saliva solution (pH=6.3) at 37°C employing electrochemical measurements. The results indicate that the Co-based BMGs exhibit much higher corrosion resistance in the simulated body solutions than that of 316L SS. Compared with the corrosion resistance of ASTM F75, that of Co70Cr5Mo5P14B6 and Co65Cr5Mo10P14B6 BMGs is found to be lower and that of Co60Cr10Mo10P14B6 BMG is higher. The concentrations of Co, Cr, and Mo ions released into the simulated body solutions from our Co-based BMGs after potentiodynamic polarization are significantly lower than that released from ASTM F75. The biocompatibility of the specimens was evaluated using an in vitro test of NIH3T3 cell culture in the specimen extraction media for 1, 3, 5, and 7days, revealing the non-cytotoxicity of the Co-based BMGs towards NIH3T3 cells. Moreover, examinations on the cell adhesion and growth on the surface of the specimens indicate that the Co-based BMGs exhibit better cell viability compared to ASTM F75 and 316L SS biomedical alloys.