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1.
Int J Biol Macromol ; 273(Pt 2): 133037, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38897523

RESUMEN

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.


Asunto(s)
Carbono , Capacidad Eléctrica , Lignina , Nanofibras , Lignina/química , Nanofibras/química , Carbono/química , Electrodos , Técnicas Electroquímicas/métodos
2.
Int J Biol Macromol ; 265(Pt 2): 131085, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38521335

RESUMEN

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.


Asunto(s)
Celulosa , Nanopartículas Multifuncionales , Biomasa , Lignina/química , Tecnología
3.
Zhongguo Xiu Fu Chong Jian Wai Ke Za Zhi ; 38(4): 426-431, 2024 Apr 15.
Artículo en Zh | MEDLINE | ID: mdl-38632061

RESUMEN

Objective: To explore the effectiveness of using antibiotic bone cement-coated plates internal fixation technology as a primary treatment for Gustilo type ⅢB tibiofibular open fractures. Methods: The clinical data of 24 patients with Gustilo type ⅢB tibiofibular open fractures who were admitted between January 2018 and December 2021 and met the selection criteria was retrospectively analyzed. Among them, there were 18 males and 6 females, aged from 25 to 65 years with an average age of 45.8 years. There were 3 cases of proximal tibial fracture, 6 cases of middle tibial fracture, 15 cases of distal tibial fracture, and 21 cases of fibular fracture. The time from injury to emergency surgery ranged from 3 to 12 hours, with an average of 5.3 hours. All patients had soft tissue defects ranging from 10 cm×5 cm to 32 cm×15 cm. The time from injury to skin flap transplantation for wound coverage ranged from 1 to 7 days, with an average of 4.1 days, and the size of skin flap ranged from 10 cm×5 cm to 33 cm×15 cm. Ten patients had bone defects with length of 2-12 cm (mean, 7.1 cm). After emergency debridement, the tibial fracture end was fixed with antibiotic bone cement-coated plates, and the bone defect area was filled with antibiotic bone cement. Within 7 days, the wound was covered with a free flap, and the bone cement was replaced while performing definitive internal fixation of the fracture. In 10 patients with bone defect, all the bone cement was removed and the bone defect area was grafted after 7-32 weeks (mean, 11.8 weeks). The flap survival, wound healing of the affected limb, complications, and bone healing were observed after operation, and the quality of life was evaluated according to the short-form 36 health survey scale (SF-36 scale) [including physical component summary (PCS) and mental component summary (MCS) scores] at 1 month, 6 months after operation, and at last follow-up. Results: All 24 patients were followed up 14-38 months (mean, 21.6 months). All the affected limbs were successfully salvaged and all the transplanted flaps survived. One case had scar hyperplasia in the flap donor site, and 1 case had hypoesthesia (grade S3) of the skin around the scar. There were 2 cases of infection in the recipient area of the leg, one of which was superficial infection after primary flap transplantation and healed after debridement, and the other was sinus formation after secondary bone grafting and was debrided again 3 months later and treated with Ilizarov osteotomy, and healed 8 months later. The bone healing time of the remaining 23 patients ranged from 4 to 9 months, with an average of 6.1 months. The scores of PCS were 44.4±6.5, 68.3±8.3, 80.4±6.9, and the scores of MCS were 59.2±8.2, 79.5±7.8, 90.0±6.6 at 1 month, 6 months after operation, and at last follow-up, respectively. The differences were significant between different time points ( P<0.05). Conclusion: Antibiotic bone cement-coated plates internal fixation can be used in the primary treatment of Gustilo type ⅢB tibiofibular open fractures, and has the advantages of reduce the risk of infection in fracture fixation, reducing complications, and accelerating the functional recovery of patients.


Asunto(s)
Fracturas Abiertas , Traumatismos de los Tejidos Blandos , Fracturas de la Tibia , Masculino , Femenino , Humanos , Persona de Mediana Edad , Tibia/cirugía , Cementos para Huesos , Fracturas Abiertas/cirugía , Antibacterianos , Cicatriz/cirugía , Estudios Retrospectivos , Calidad de Vida , Resultado del Tratamiento , Fracturas de la Tibia/cirugía , Trasplante de Piel , Fijación Interna de Fracturas/efectos adversos , Traumatismos de los Tejidos Blandos/cirugía
4.
Sci Rep ; 13(1): 21890, 2023 12 11.
Artículo en Inglés | MEDLINE | ID: mdl-38082020

RESUMEN

Complex lower extremity trauma reconstruction remains a challenge. This study used an internal fixation composite structure of antibiotic cement plates as a temporary fixation to treat lower extremity Grade III open fractures; thus, reducing the treatment period and complications of external fixation. We aimed to assess the safety and efficacy of this technique in the initial surgery stage. Between January 2018 and March 2021, 20 patients with Gustilo grade IIIB/C open fractures received an antibiotic cement-coated locking plate as a temporary internal fixator during initial surgery. Thorough debridement and temporary internal fixation were performed with a 3.5-mm system antibiotic cement-coated locking plate. Ten patients required free bone fragment removal, followed by bone cement packing. The final stage involved internal fixation and wound repair with a free anterolateral thigh flap. Clinical and imaging results were retrospectively analysed. The repair time ranged 1-7 days. All flaps survived. Two patients experienced wound infection, and one developed severe bone infection 3 months after three-stage bone graft surgery. Autologous cancellous bone grafting was performed on 10 patients with bone defects 6 weeks after surgery. Bone union was universally achieved after 1 year. This method proved safe and effective, successfully repairing Grade III open fractures of the lower extremity 1-7 days post-treatment.


Asunto(s)
Fracturas Abiertas , Colgajos Tisulares Libres , Fracturas de la Tibia , Humanos , Fracturas Abiertas/cirugía , Antibacterianos/uso terapéutico , Cementos para Huesos/uso terapéutico , Estudios Retrospectivos , Resultado del Tratamiento , Fracturas de la Tibia/diagnóstico por imagen , Fracturas de la Tibia/cirugía , Fracturas de la Tibia/tratamiento farmacológico , Fijación Interna de Fracturas/métodos , Placas Óseas , Fijación de Fractura/métodos
5.
Sci Total Environ ; 858(Pt 3): 160075, 2023 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-36372178

RESUMEN

Plastic pollution in the environment has spurred debate among scientists, policymakers, and the general public over how industrialization and consumerism are wreaking havoc on our ecosystem, but some policies might assist to ameliorate the problem in the near future. In this study, the decision tree classifier and Bayesian Structural Time Series (BSTS) model was used to anticipate the possible sources of microplastics and their near future state in 26 surface sediment and a sediment core, respectively in Sansha Bay, which has been criticized for its intensive mariculture applications. An inventory of microplastics in the sediment core was estimated, and it was discovered that during the previous six decades, an average of 181.95 tons of microplastics were deposited, with an average deposition (by a layer of sediment) of 179.44 tons/cm. According to the DT classifier, mariculture was the primary source of microplastics, whereas urban and industrial areas were the primary sources of POPs. The Bayesian Structural Time Series (BSTS) model revealed a microplastic downward slope, indicating that regional and national strategies implemented might successfully reduce microplastic pollution regionally.


Asunto(s)
Microplásticos , Plásticos , Teorema de Bayes , Bahías , Ecosistema , Modelos Estadísticos
6.
Environ Pollut ; 294: 118640, 2022 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-34875265

RESUMEN

As reservoirs for pollutants transported via the Yangtze and Yellow Rivers, the Bohai Sea (BS) and Yellow Sea (YS) play an important role in transporting microplastics (MPs) to the Pacific Ocean. The fate, sources and mass budget of MPs in the BS and the YS were investigated by Pearson correlation, principal component analysis-multilinear regression analysis (PCA-MRLA) and a mass balance model to sedimentary MPs data. Average MP abundances were 137 and 119 items kg-1 in the Bohai and Yellow Seas, respectively. MPs <1000 µm exhibited similar distribution patterns to total organic carbon and fine-grained sediments, while MPs >1000 µm were confined in the BS and exhibited a strong positive correlation with chlorophyll-a and polyethylene terephthalate, suggesting that larger MPs might deposit faster due to biofouling or when comprised of high density polymers. PCA-MLRA analysis indicated land-based inputs (packing materials, textile material and daily commodities) were dominant in the BS, while maritime activities (fishing and mariculture) were the main source of MPs in the YS. The mass balance model revealed that the total MP input and output to the BS and the YS was 3396.92 t yr-1 and 3814.81 t yr-1, respectively. The major input pathway of MPs to the BS and the YS were river discharge and air deposition, respectively. Notably, 94% of MPs in the BS and the YS were deposited to sediments. This study revealed that BS and YS sediments play an important role in preventing MPs from being further transported to the Pacific Ocean, thus more attention should be paid to local ecological risk assessment.


Asunto(s)
Microplásticos , Contaminantes Químicos del Agua , China , Monitoreo del Ambiente , Sedimentos Geológicos , Océanos y Mares , Plásticos , Contaminantes Químicos del Agua/análisis
7.
Mar Pollut Bull ; 175: 113351, 2022 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-35123274

RESUMEN

Luoyuan Bay is a mariculture influenced water body located in southeastern China. Multi-statistical techniques were applied to 21 sampling locations in the bay to identify the sources of microplastics and other pollutants in the sediment. In microplastics detection, fragment was the most abundant shape (~36%), and rayon was the dominant polymer (~59%). The size of more than 48% of total microplastics observed was less than 200 µm. The study showed that the upper part of Luoyuan Bay was dominated by microplastic pollution, while the lower part of the bay was dominated by persistent organic pollutants (PAHs, OCPs). Mariculture is one of the main sources of pollution in Luoyuan Bay. Apart from mariculture, there were additional sources such as industry, land reclamation, port, and so on; industry and land reclamation were the leading sources of microplastics, while port, industry, and mariculture were the primary sources of PAHs and OCPs.


Asunto(s)
Microplásticos , Contaminantes Químicos del Agua , Bahías , China , Monitoreo del Ambiente , Plásticos/análisis , Contaminantes Químicos del Agua/análisis
8.
ACS Appl Mater Interfaces ; 10(31): 26604-26609, 2018 Aug 08.
Artículo en Inglés | MEDLINE | ID: mdl-30004660

RESUMEN

In this work, we report a wearable thermal detector based on poly(vinyl alcohol) and carbon nanotube (CNT) composite via photo-thermoelectric effect. Passive room-temperature human body thermal imaging is demonstrated with optimum detectivity up to 4.9 × 106 cm Hz1/2 W-1. Highly stable photoresponse (variation < 4%) is obtained under a bending radius down to 3.5 mm. We also found that the detector photoresponse is influenced by the composite channel length because of Seebeck effect. This flexible, self-powered, and sensitive detector opens up opportunities for wearable thermal imaging and real-time health monitoring.


Asunto(s)
Nanotubos de Carbono , Humanos , Polímeros , Temperatura , Dispositivos Electrónicos Vestibles
9.
J Plast Reconstr Aesthet Surg ; 63(2): 227-32, 2010 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-19091642

RESUMEN

BACKGROUND: The use of artificial bone graft substitutes has increased as the surgical applications widen and the availability of allograft bone decreases. The present study was to evaluate the construct combined bone marrow stromal cells (BMSCs) with beta-tricalcium phosphate (beta-TCP) as bone substitute implanted in rat dorsal muscles. METHODS: To study the osteogenic capability in vivo, specimens were harvested on 1 week, 4 weeks and 8 weeks after implantation, and were analyzed by hematoxylin and eosin (HE) staining. The percentages of new bone formation for each implant type and implantation period were determined by histomorphometry. RESULTS: After 1 week of implantation, new bone formation for both beta-TCP and BMSCs+beta-TCP group had no formed. After 4 weeks of implantation, the amount of bone formation was increased to 1.32 % in beta-TCP group and 6.35% in BMSCs+beta-TCP group. After 8 weeks of implantation, more bone was found in the BMSCs+beta-TCP group (21.58 %), while in the beta-TCP group bone formation was increased to 4.78%. Significant differences between the two groups have been observed. CONCLUSIONS: Based on these results, we conclude that bone substitutes constructed by porous beta-TCP scaffold loaded with osteogenically induced BMSCs could promote newly formed bone.


Asunto(s)
Células de la Médula Ósea/citología , Sustitutos de Huesos/farmacología , Fosfatos de Calcio/farmacología , Osteogénesis/fisiología , Células del Estroma/citología , Análisis de Varianza , Animales , Materiales Biocompatibles , Ratas , Ratas Sprague-Dawley , Ingeniería de Tejidos/métodos
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