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Vanadium redox flow battery (VRFB) has garnered significant attention due to its potential for facilitating the cost-effective utilization of renewable energy and large-scale power storage. However, the limited electrochemical activity of the electrode in vanadium redox reactions poses a challenge in achieving a high-performance VRFB. Consequently, there is a pressing need to assess advancements in electrodes to inspire innovative approaches for enhancing electrode structure and composition. This work categorizes three-dimensional (3D) electrodes derived from materials such as foam, biomass, and electrospun fibers. By employing a flexible electrode design and compositional functionalization, high-speed mass transfer channels and abundant active sites for vanadium redox reactions can be created. Furthermore, the incorporation of 3D electrocatalysts into the electrodes is discussed, including metal-based, carbon-based, and composite materials. The strong interaction and ordered arrangement of these nanocomposites have an influence on the uniformity and stability of the surface charge distribution, thereby enhancing the electrochemical performance of the composite electrodes. Finally, the challenges and perspectives of VRFB are explored through advancements in 3D electrodes, 3D electrocatalysts, and mechanisms. It is hoped that this review will inspire the development of methodology and concept of 3D electrodes in VRFB, so as to promote the future development of scientific energy storage and conversion technology.
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Vanadium redox flow battery (VRFB) is a type of energy storage device known for its large-scale capacity, long-term durability, and high-level safety. It serves as an effective solution to address the instability and intermittency of renewable energy sources. Carbon-based materials are widely used as VRFB electrodes due to cost-effectiveness and well-stability. However, pristine electrodes need proper modification to overcome original poor hydrophilicity and fewer reaction active sites. Adjusting the carbon structure is recognized as a viable method to boost the electrochemical activity of electrodes. This review delves into the advancements in research related to ordered and disordered carbon structure electrodes including the adjusting methods, structural characteristics, and catalytic properties. Ordered carbon structures are categorized into nanoscale and macroscale orderliness based on size, leading to improved conductivity and overall performance of the electrode. Disordered carbon structures encompass methods such as doping atoms, grafting functional groups, and creating engineered holes to enhance active sites and hydrophilicity. Based on the current research findings on carbon electrode structures, this work puts forth some promising prospects for future feasibility.
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Biomass-derived carbon (BDC) materials are suitable as electrode or catalyst materials for vanadium redox flow battery (VRFB), owing to the characteristics of vast material sources, environmental friendliness, and multifarious structures. A timely and comprehensive review of the structure and property significantly facilitates the development of BDC materials. Here, the paper starts with the preparation of biomass materials, including carbonization and activation. It is designed to summarize the lastest developments in BDC materials of VRFB in four different structural dimensions from zero dimension (0D) to three dimension (3D). Every dimension begins with meticulously selected examples to introduce the structural characteristics of materials and then illustrates the improved performance of the VRFB due to the structure. Simultaneously, challenges, solutions, and prospects are indicated for the further development of BDC materials. Overall, this review will help researchers select excellent strategies for the fabrication of BDC materials, thereby facilitating the use of BDC materials in VRFB design.
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In spite of their low cost, high activity, and diversity, metal oxide catalysts have not been widely applied in vanadium redox reactions due to their poor conductivity and low surface area. Herein, SnO2/reduced graphene oxide (SnO2/rGO) composite was prepared by a sol-gel method followed by high-temperature carbonization. SnO2/rGO shows better electrochemical catalysis for both redox reactions of VO2+/VO2+ and V2+/V3+ couples as compared to SnO2 and graphene oxide. This is attributed to the fact that reduced graphene oxide is employed as carbon support featuring excellent conductivity and a large surface area, which offers fast electron transfer and a large reaction place towards vanadium redox reaction. Moreover, SnO2 has excellent electrochemical activity and wettability, which also boost the electrochemical kinetics of redox reaction. In brief, the electrochemical properties for vanadium redox reactions are boosted in terms of diffusion, charge transfer, and electron transport processes systematically. Next, SnO2/rGO can increase the energy storage performance of cells, including higher discharge electrolyte utilization and lower electrochemical polarization. At 150 mA cm-2, the energy efficiency of a modified cell is 69.8%, which is increased by 5.7% compared with a pristine one. This work provides a promising method to develop composite catalysts of carbon materials and metal oxide for vanadium redox reactions.
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Dried pericarps of Citrus reticulata 'Chachi', named Guangchenpi (GCP), have been used as both food and medicine in China for centuries. Due to its special flavour and taste, the price of GCP is much higher than those of dried pericarps from other Citrus reticulata Blanco varieties (collectively called "Chenpi", CP). Therefore, some CP have been disguised has GCP by dishonest businessmen to obtain a higher profit. In this study, a simple, rapid, effective and economic analytical method based on headspace-gas chromatography-ion mobility spectrometry (HS-GC-IMS) was established to discriminate GCP and CP by their volatile organic compounds (VOCs). Principal component analysis (PCA) was performed to extract meaningful attributes from VOCs based on the GC-IMS chromatograms and to give the analysis results. Twelve, 12 and 14 markers were identified and established as the characteristic fingerprints of GCP analysis of 45 batches of samples via SE-54, OV-1701 and Inter Cap WAX gas chromatographic columns, respectively. The PCA results indicated that GCP and CP could be effectively discriminated. This study confirmed the potential of HS-GC-IMS combined with PCA as a reliable analytical screening technique to discriminate between GCP and CP.
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Cromatografia Gasosa , Citrus/química , Espectrometria de Mobilidade Iônica , Análise de Componente Principal , Compostos Orgânicos VoláteisRESUMO
Adolescent idiopathic scoliosis (AIS) is a common disease with the age of 10 to 18 years, the Cobb angle more than 10 ° on the coronal plane and combined with the rotation of the vertebral body without other organic lesions. The disease can lead to deformity, pain and even damage of cardiopulmonary function, which seriously affects the physical and mental health and quality of life of patients. For mild to moderate AIS patients, regular observation, braces and other conservative treatment methods can effectively delay the progress of scoliosis. For AIS patients whose conservative treatment is ineffective and reaches the surgical threshold, surgery is recommended. Currently, the prevalent surgical method is posterior vertebral body fusion represented by the pedicle screw internal fixation system, which can often achieve good clinical efficacy. In recent years, Physical Therapeutic Scoliosis Specific Exercise (PSSE) has become more and more popular because of its safety and effectiveness. At present, the specific indications for the treatment of AIS patients are gradually improving, the concept and technology of treatment are constantly updated, and the clinical efficacy is constantly improved. This article will start from two aspects of conservative treatment and surgical treatment, mainly describes the commonly used treatment methods in clinical progress and application as well as the problems faced, in order to provide a reference for the selection of clinical treatment.
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Escoliose , Fusão Vertebral , Adolescente , Humanos , Qualidade de Vida , Radiografia , Estudos Retrospectivos , Vértebras Torácicas , Resultado do TratamentoRESUMO
Ultra-high-performance liquid chromatography coupled with quadrupole/time-of-flight mass spectrometry (UHPLC-Q/TOF-MS) in positive ion mode was used to profile and identify the major constituents in Euphorbia fischeriana Steud. (E. fischeriana). An Agilent ZORBAX SB-C18 column was used to separate the crude extract of E. fischeriana, and the mobile phases were acetonitrile and 0.1% aqueous formic acid (v/v). A total of 40 peaks were detected, and 37 components, including phloroglucinol derivatives, diterpenoids and nitrogenous compounds, were identified based on their accurate masses and fragmentation characteristics. The chemical structures of 7 of the detected compounds were determined by comparing standard compounds to the compounds that were isolated from E. fischeriana. Reasonable fragmentation mechanisms and key fragment ions of the four jolkinolide components were determined to aid in the identification of the other diterpenoids in E. fischeriana. In addition, the compound corresponding to peak 18, namely, jolkinomethylide, was determined to be new, and its chemical structure was determined and elucidated based on MS and NMR spectroscopic data. The present study provided valuable information on the new components in E. fischeriana and established a practical method for evaluating the quality of E. fischeriana.
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Medicamentos de Ervas Chinesas/análise , Medicamentos de Ervas Chinesas/química , Euphorbia/química , Espectrometria de Massas em Tandem/métodos , Cromatografia Líquida de Alta Pressão/métodosRESUMO
OBJECTIVE: To establish a method for the determination of eighteen elements (Be, Al, Cr, Mn, Ni, Cu, As, Se, Mo, Ag, Cd, Sn, Sb, Ba, Dy, Hg, Tl and Pb) in Serratulae Chinensis Radix by inductively coupled plasma-mass spectrography (ICP-MS). METHODS: After microwave digestion, 18 elements in the samples were determined by ICP-MS and the method was validated. RESULTS: A good linearity of calibration curves was obtained, the mean recovery met the analytical requirement. CONCLUSION: This method is simple, accurate and effective. It provides basis for the research of Serratulae Chinensis Radix.
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Asteraceae/química , Espectrometria de Massas/métodos , Oligoelementos/análise , Asteraceae/crescimento & desenvolvimento , Limite de Detecção , Micro-Ondas , Raízes de Plantas/química , Controle de Qualidade , Reprodutibilidade dos Testes , Sensibilidade e EspecificidadeRESUMO
Euphorbia ebracteolata Hayata (E. ebracteolata) is a Chinese herbal medicine used for the treatment of tumor diseases. An ultra-performance liquid chromatography/quadrupole time-of-flight mass spectrometry (UPLC-Q-TOF/MS) based chemical profiling approach was established for the rapid separation and characterization on phloroglucinol derivatives and diterpenes in E. ebracteolata. Three phloroglucinol derivatives and nine diterpenes were identified by exact mass measurement and were further confirmed by Ms2 data. In addition, the chemical profiles of six compounds were acquired by reference standards. Furthermore, the fragmentation rules of phloroglucinol derivatives and diterpenes of E. ebracteolata were analyzed, and each chromatographic peak was classified.
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OBJECTIVE: To analyze coumarins in Fructus Cnidii by HPLC-ESI-MS. METHODS: Coumarins in Fructus Cnidii were subjected to HPLC, using Shim-pack CLC-ODS column, methanol-water (70:30) as mobile phase, and 254 nm as DAD wavelength. A quadrupole mass spectrometer was applied to verify the LC elute, operated in the positive ion mode. RESULTS: Three coumarins were determined and the possible structures of seven coumarins were deduced based on the chromatography and MS data. CONCLUSION: The application of this method could be available for the rapid identification of constituents from traditional Chinese medicines.