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1.
Int J Biol Macromol ; 276(Pt 2): 133939, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39029827

RESUMEN

Pea protein isolate (PPI) was used as a carrier matrix to load tannic acid (TA) due to its multiple cavity structures and reaction sites, after that, magnesium ion (M) was further added to form more stable carrier structures. PPI was covalently bound with TA to form TA-PPI complexes in alkaline conditions, then M induced the aggregation of TA-PPI to produce M-TA-PPI complexes. TA mainly interacted with free amino groups and sulfhydryl groups of PPI, thereby decreasing their content in complexes. TA further decreased the α-helix content and increased the ß-sheet and ß-turn content in TA-PPI complexes correspondingly, nevertheless the M would decline these changes in M-TA-PPI complexes. As a result of binding, TA and M jointly increased the average molecular size of complexes. The higher TA addition amount (10-20 mg/g PPI) was conducive to the stronger intramolecular interactions (more hydrophobic interactions and disulfide bonds), gel structure (higher hardness value) and storage modulus in M-TA-PPI gels. Compared with TA-PPI complexes, M-TA-PPI complexes showed higher stability in gastric digestion and higher TA releasement and antioxidant capacity of its digesta in intestinal digestion. This kind of metal-phenolics-protein complexes may have potentials to be a stable and efficient carrier for loading gastric sensitive polyphenols.


Asunto(s)
Magnesio , Proteínas de Guisantes , Polifenoles , Antioxidantes/química , Sustancias Macromoleculares/química , Magnesio/química , Proteínas de Guisantes/química , Proteínas de Guisantes/aislamiento & purificación , Pisum sativum/química , Polifenoles/química
2.
Food Chem ; 446: 138861, 2024 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-38430767

RESUMEN

A ternary complex composed of soybean protein isolated (SPI), tannic acid (TA) and magnesium ion (M) was established to enhance the capability of protein carriers for TA delivery. SPI was firstly covalently bind with TA (TA-SPI) and then M was employed to form the ternary complex (M-TA-SPI). Their structures, gel and digestion properties were further investigated. TA was observed to covalently bind with SPI. TA-SPI and M-TA-SPI complexes showed different molecule size and spatial structures after binding with M and TA. The increasing of TA amount changed the intramolecular interactions, microstructure and texture properties of M-TA-SPI gels. Compared with TA-SPI, M retarded the gastric digestion of M-TA-SPI and caused higher TA release amount in intestinal tract. In this study, M-TA-SPI was determined to be a good carrier to protect and release TA in gastrointestinal digestion. This kind of complex may have potential applications for loading polyphenols in nutraceuticals.


Asunto(s)
Magnesio , Proteínas de Soja , Proteínas de Soja/química , Polifenoles
3.
Nano Lett ; 23(19): 9011-9019, 2023 Oct 11.
Artículo en Inglés | MEDLINE | ID: mdl-37676743

RESUMEN

Freeze-casting has been wildly exploited to construct porous ceramics but usually requires costly and demanding freeze-drying (high vacuum, size limit, and supercooled chamber), which can be avoided by the ambient pressure drying (APD) technique. However, applying APD to freeze-cast ceramic based on an aqueous suspension is still challenging due to inert surface chemistry. Herein, a modified APD strategy is developed to improve the drying process of freeze-cast ceramics by exploiting the simultaneous ice etching, ionic cross-linking, and solvent exchange under mild conditions (-10-0 °C, ambient pressure). This versatile strategy is applicable to various ceramic species, metal ions, and freezing techniques. The incorporated metal ions not only enhance liquid-phase sintering, producing ceramics with higher density and mechanical properties than freeze-cast counterparts, but also render customizable coloration and antibacterial property. The cost-/time-efficient APD is promising for mass production and even successive production of large-size freeze-cast ceramics that exceed the size of commercial freeze-dryers.

4.
Adv Mater ; 35(39): e2303518, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37326618

RESUMEN

Soft woods have attracted enormous interest due to their anisotropic cellular microstructure and unique flexibility. The conventional wood-like materials are usually subject to the conflict between the superflexibility and robustness. Inspired by the synergistic compositions of soft suberin and rigid lignin of cork wood which has good flexibility and mechanical robustness, an artificial soft wood is reported by freeze-casting the soft-in-rigid (rubber-in-resin) emulsions, where the carboxy nitrile rubber confers softness and rigid melamine resin provides stiffness. The subsequent thermal curing induces micro-scale phase inversion and leads to a continuous soft phase strengthened by interspersed rigid ingredients. The unique configuration ensures crack resistance, structural robustness and superb flexibility, including wide-angle bending, twisting, and stretching abilities in various directions, as well as excellent fatigue resistance and high strength, overwhelming the natural soft wood and most wood-inspired materials. This superflexible artificial soft wood represents a promising substrate for bending-insensitive stress sensors.

5.
Angew Chem Int Ed Engl ; 62(5): e202214809, 2023 Jan 26.
Artículo en Inglés | MEDLINE | ID: mdl-36445797

RESUMEN

Cellulose aerogels are plagued by intermolecular hydrogen bond-induced structural plasticity, otherwise rely on chemicals modification to extend service life. Here, we demonstrate a petrochemical-free strategy to fabricate superelastic cellulose aerogels by designing hierarchical structures at multi scales. Oriented channels consolidate the whole architecture. Porous walls of dehydrated cellulose derived from thermal etching not only exhibit decreased rigidity and stickiness, but also guide the microscopic deformation and mitigate localized large strain, preventing structural collapse. The aerogels show exceptional stability, including temperature-invariant elasticity, fatigue resistance (∼5 % plastic deformation after 105  cycles), high angular recovery speed (1475.4° s-1 ), outperforming most cellulose-based aerogels. This benign strategy retains the biosafety of biomass and provides an alternative filter material for health-related applications, such as face masks and air purification.

6.
Clin Lab ; 68(10)2022 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-36250845

RESUMEN

BACKGROUND: Leukopenia is the most common adverse event in chemotherapy, which natural products can prevent and treat. The aim of this study was to investigate the clinical efficacy of potato extract for alleviating chemoradiotherapy-induced leukopenia in cancer patients. METHODS: This was a single-blinded randomized placebo-controlled trial that enrolled 184 cancer patients. The participants were scheduled to undergo chemoradiotherapy in two hospitals, where they were randomized to receive potato extract or a placebo in a 1:1 ratio for a period of 49 days. Change in leukocyte value was considered the primary outcome of this clinical trial. Secondary outcomes included tumor response rate, blood test, and quality of life score. RESULTS: The leukopenia was relieved in the potato extract group compared with the placebo group. Of note, a significant difference in leukopenia between the two groups was found after 14 days (p = 0.04). In addition, there was no statistically significant difference in leucocyte levels in the potato extract group (before and after potato extract treatment; p = 0.13), but in the placebo group, the leukocyte value significantly decreased compared to before treatment (p = 0.06). CONCLUSIONS: Potato extract can alleviate chemoradiotherapy-induced leukopenia in cancer patients. These results show the potential function of potato extract as a protective agent in management of cancer chemoradiotherapy.


Asunto(s)
Productos Biológicos , Leucopenia , Neoplasias , Solanum tuberosum , Quimioradioterapia/efectos adversos , Quimioradioterapia/métodos , Método Doble Ciego , Humanos , Leucopenia/inducido químicamente , Neoplasias/tratamiento farmacológico , Neoplasias/radioterapia , Calidad de Vida , Método Simple Ciego , Resultado del Tratamiento
7.
J Food Sci ; 87(10): 4504-4521, 2022 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-36124403

RESUMEN

The potential uses of Ligustrum robustum (Rxob.) Blume extract as a natural antioxidant to protect the quality of different oils during storage and frying process were studied. The results showed that L. robustum extract has been shown to retard the decline in the quality of both oils based on the tests of acid value, peroxide value, p-anisidine value, color, volatile flavor, and fatty acid compositions, and the protective effect of L. robustum extract on the quality of peanut oil was better than that of palm oil. By the component analysis, L. robustum extract was found to have a total phenols content of 140.75 ± 1.52 mg/g, and ligurobustoside C was identified as the main phenolic compound. The thermogravimetric and differential scanning calorimetry results showed that L. robustum extract enhanced the oxidative stability of peanut and palm oils. In addition, Fourier transform infrared results indicated that L. robustum extract had protective effects on the C=C bond and ester bond of oil molecule. Moreover, by using electron spin resonance technique, L. robustum extract showed the ability to inhibit and scavenge alkyl-free radicals in both oils. The present results suggested that L. robustum extract may protect the quality of oils during the storage and frying process by inhibiting the oxidation of unsaturated fatty acids and might be a potential natural antioxidant in the food industry. PRACTICAL APPLICATIONS: The excellent antioxidant ability of Ligustrum robustum (Rxob.) Blume extract on the oxidation of different oils and its low price indicated that it could be used as a new low-cost natural antioxidant in oil processing.


Asunto(s)
Ligustrum , Ligustrum/química , Aceite de Palma , Antioxidantes/química , Arachis , Aceite de Cacahuete , Fenoles/química , Extractos Vegetales/química , Ácidos Grasos/análisis , Peróxidos/análisis , Ácidos Grasos Insaturados , Ésteres
8.
Front Endocrinol (Lausanne) ; 13: 861070, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35651976

RESUMEN

Partially cystic thyroid nodules (PCTNs) are a kind of thyroid nodule with both solid and cystic components, and are usually misdiagnosed as benign nodules. The objective of this study was to determine the ultrasound (US) characterizations with a TIRADS Grade-4a or higher partially cystic thyroid nodules (PCTNs) which are associated with being malignant or benign. In this study, 133 PCTNs with a TIRADS Grade-4a or higher were enrolled; 83 were malignant and 50 were benign. TI-RADS classification can detect malignant PCTNs, and its sensitivity, specificity, positive predictive value, negative predictive value, and accuracy are 39.8%, 96.0%, 94.3%, 49.0%, and 60.9%, respectively. Univariate analyses revealed that nodule shape, margin, and structure were related to PCTNs' being benign and malignant, among which nodules taller-than-wide, with an irregular shape, non-smooth margin, eccentric sharp angle, or edge sharp angle were significantly associated with malignancy while ovoid to round nodules, smooth margins, multiple separation, and eccentric obtuse angle structures were significantly associated with a benign nature. For the solid part of PCTNs, its free margin, echo, and calcification are related to benign and malignant PCTNs. Among them, the free margin of the solid part is non-smooth, hypoechoic, and microcalcification, which are related to malignant PCTNs, while the free margin of the solid part is smooth, isoechoic, macrocalcification, non-calcification and are related to benign PCTNs. Calcification of solid part and free margin are important factors for predicting malignant PCTNs. In addition, nodules' composition, blood flow signal, and other factors had nothing to do with PCTNs' being benign or malignant. In the multivariate Logistic regression analysis, solid part calcification (OR: 17.28; 95%CI: 5.14~58.08) and free margin (OR: 3.18; 95%CI: 1.01~10.00) were revealed to be the strongest independent predictors for malignancy (P<0.05). Our study indicated that understanding the ultrasound characteristics of malignant PCTNs, to avoid misdiagnosed PCTNs patients, is important to make a precise diagnosis and prognosis of PCTNs.


Asunto(s)
Calcinosis , Nódulo Tiroideo , Calcinosis/diagnóstico por imagen , Diagnóstico Diferencial , Humanos , Valor Predictivo de las Pruebas , Nódulo Tiroideo/diagnóstico por imagen , Nódulo Tiroideo/patología , Ultrasonografía
9.
Int J Food Sci Nutr ; 73(6): 786-799, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-35603582

RESUMEN

The effect of tea polyphenols (TPs) on noodles quality was investigated, and the interaction mechanism between catechins and gliadins was explored. With TPs addition, noodles showed the significant changes in physicochemical and sensory properties. The water absorption, tensile strength and elasticity increased by 1.35%, 4.98%, 28.51% with 0.5% of TPs, and then decreased with the increasing of TPs. According to the determinations of surface hydrophobicity, spatial structure, thermal properties, amidogen and sulfhydryl content, the structure and properties of gliadin were affected by catechins. Esterified catechins tended to disrupt gliadin structures and non-esterified catechins polymerised gliadin molecules. Furthermore, molecular docking results indicated that catechins interacted with gliadin mainly by hydrogen bonds and hydrophobic action. The reactivity of catechins with gliadin was in the sequence as: epigallocatechin gallate > epicatechin gallate > epigallocatechin > epicatechin, which was based on the account of gallate and B-ring hydroxyl number discrepancy. All results suggested that catechins affected greatly on gliadin, and TPs were potentially used to improve the quality of flour products.


Asunto(s)
Catequina , Polifenoles , Catequina/química , Gliadina , Enlace de Hidrógeno , Simulación del Acoplamiento Molecular , Polifenoles/farmacología , Té/química
10.
J Food Sci ; 87(4): 1500-1513, 2022 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-35279847

RESUMEN

Effect of tea polyphenols (TP) on the quality of Chinese steamed bun (CSB) was investigated, while the interaction and action mechanism between TP and vital wheat gluten (VWG, constitutive proteins of flour) were further explored. With a low concentration (1%) of TP, CSB showed positive changes in quality, and the hardness of CSB decreased by 33.95%, while its specific volume, springiness, and resilience separately increased by 1.8%, 11.9%, and 5.5%, whereas the higher concentrations of TP (2% and 4%) caused an adverse impact. By observation of scanning electron microscope, VWG formed a fluffier structure with a low concentration of TP, while the structure deteriorated at high concentration of TP. In addition, the secondary and tertiary structures of VWG were both changed by TP. Along with the results of thermodynamic analysis (thermogravimetric and differential scanning calorimetry measurements), TP could induce the structural rearrangement of VWG. Further, a lower amidogen and sulfhydryl contents of VWG were obtained in TP groups, which illustrated that peptide and disulfide bonds of VWG were not possibly interrupted by TP. Instead, hydrophobic residues of VWG were bonded to form a more hydrophilic structure. Moreover, according to molecular docking results, epigallocatechin-3-gallate interacted tightly with VWG by hydrogen bonds and hydrophobic actions, and the action sites were mainly at hydrophobic and hydrophilic residues. All results suggested that the VWG structure was affected greatly by TP, and a low dose of TP might be potential to improve the quality of flour products. PRACTICAL APPLICATION: The physicochemical properties of gluten show the significant effects on the quality of flour products in food industry. In the present study, a low dose of tea polyphenols exhibited a strengthened effect on gluten, so as to ameliorate the texture of Chinese steamed bun (CSB) due to their tight interactions with gluten, while the color of CSB was changed to brown as tea polyphenols. All results suggested that a low dose of tea polyphenols could be potentially utilized to improve flour quality and enhance gluten strength in food industry.


Asunto(s)
Glútenes , Polifenoles , China , Glútenes/química , Simulación del Acoplamiento Molecular , Polifenoles/química , Vapor , Té/química
11.
Food Res Int ; 148: 110593, 2021 10.
Artículo en Inglés | MEDLINE | ID: mdl-34507738

RESUMEN

Effects of different phenolic compounds on the structural and functional properties of myofibrillar protein (MP) were investigated, and the phenolic compounds were applied as natural modifiers in pork meatball. Interactions between MP and phenolic compounds were determined via molecular docking to elucidate the modification mechanisms. Tannic acid, gallic acid, (-)-epigallocatechin gallate, and epigallocatechin interacted with MP primarily through hydrogen bonds, which unfolded the secondary structures of MP and lowered surface hydrophobicity. Accordingly, the solubility, gel properties, and oxidation stability of MP were improved, while the emulsifying properties significantly decreased. Quercetin and quercitrin showed electrostatic interactions with MP, which preserved α-helix structures and increased surface hydrophobicity. While, the modifications lent MP the enhanced emulsifying properties, thermal stability, and oxidation stability, but the gel properties and solubility were mitigated. In addition, the incorporation of phenolic compounds prevented MP oxidation based upon their antioxidant abilities deriving from hydroxyl groups. Once the phenolic compounds were used in pork meatball, a minced meat model, they significantly improved the quality of meatball by bettering the texture properties and controlling the oxidation level. The results suggest that phenolic compounds have great potential to be employed as natural additives in minced meat products for the modification of functional properties.


Asunto(s)
Carne de Cerdo , Carne Roja , Animales , Simulación del Acoplamiento Molecular , Proteínas Musculares , Oxidación-Reducción , Carne Roja/análisis , Porcinos
12.
Adv Mater ; 33(28): e2001086, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-32483868

RESUMEN

As an abundant natural resource, wood has gained great attention for thousands of years, spanning from the primitive construction materials to the modern high-added-value engineering materials. The unique delicate microstructures and the wonderful properties (e.g., low-density, high strength and stiffness, good toughness, and environmental sustainability) have made wood a natural source of inspiration that guides researchers to invent various wood-inspired materials. Herein, as an emerging material system, bioinspired artificial wood, with similar cellular structures and comparable mechanical properties, is discussed in the view of the design concept, fabrication strategy, properties, and possible applications. The present challenges and further research opportunities are also presented for artificial woods to thrive. To achieve the final eco-friendly artificial wood, more endeavors should be made in biomaterials and biodegradable or recyclable engineering of polymers to gain high mechanical properties and environmental sustainability simultaneously.

13.
Int J Food Sci Nutr ; 71(6): 726-737, 2020 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-32009476

RESUMEN

The interaction and action mechanism of starch with different phenolic compounds were investigated. By using scanning electron microscope, nuclear magnetic resonance, Fourier transform infra-red spectroscopy and thermogravimetric analysis, phenolic compounds exhibited the significant effects on the morphology, intensity of hydrogen bond, crystalline structure and thermal stability of starch, respectively. Furthermore, according to the analysis of molecular dynamics simulation by using short-chain glucose (SGS) as model, phenolic compounds could change the spatial configuration of starch, and had the obvious effects on the formation of hydrogen bonds (including intra- and intermolecular hydrogen bonds) and the strength of binding free energy. Meanwhile, epigallocatechin gallate possessed the strongest capacity to change the spatial configuration of starch with the consistent hydrogen bond occupancy and the lowest binding free energy. All present results suggested that phenolic compounds might be potentially utilised for improving the quality of starch in food industry.


Asunto(s)
Catequina/análogos & derivados , Ácido Clorogénico/química , Ácido Gálico/química , Enlace de Hidrógeno , Simulación de Dinámica Molecular , Almidón/ultraestructura , Taninos/química , Catequina/química , Humanos , Espectroscopía de Resonancia Magnética , Microscopía Electrónica de Rastreo , Fenoles/química , Espectroscopía Infrarroja por Transformada de Fourier , Termogravimetría
14.
Biomed Res Int ; 2019: 2920169, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31886195

RESUMEN

It has been reported that 18F-FDG uptake is higher in hypoxic cancer cells than in well-oxygenated cells. We demonstrated that 18F-FDG uptake in lung cancer would be affected by high concentration oxygen breathing. Methods. Overnight fasted non-small-cell lung cancer A549 subcutaneous (s.c.) xenografts bearing mice (n = 10) underwent 18F-FDG micro-PET scans, animals breathed room air on day 1, and same animals breathed carbogen (95% O2 + 5% CO2) on the subsequent day. In separated studies, autoradiography and immunohistochemical staining visualization of frozen section of A549 s.c. tumors were applied, and to compare between carbogen-breathing mice and those with air breathing, a combination of 18F-FDG and hypoxia marker pimonidazole was injected 1 h before animal sacrifice, and 18F-FDG accumulation was compared with pimonidazole binding and glucose transporter 1 (GLUT-1) expression. Results. PET studies revealed that tumor 18F-FDG uptake was significantly decreased in carbogen-breathing mice than those with air breathing (P < 0.05). Ex vivo studies confirmed that carbogen breathing significantly decreased hypoxic fraction detected by pimonidazole staining, referring to GLUT-1 expression, and significantly decreased 18F-FDG accumulation in tumors. Conclusions. High concentration of O2 breathing during 18F-FDG uptake phase significantly decreases 18F-FDG uptake in non-small-cell lung cancer A549 xenografts growing in mice.


Asunto(s)
Dióxido de Carbono , Carcinoma de Pulmón de Células no Pequeñas , Fluorodesoxiglucosa F18/farmacocinética , Neoplasias Pulmonares , Pulmón , Oxígeno , Células A549 , Animales , Dióxido de Carbono/farmacocinética , Dióxido de Carbono/farmacología , Carcinoma de Pulmón de Células no Pequeñas/química , Carcinoma de Pulmón de Células no Pequeñas/metabolismo , Modelos Animales de Enfermedad , Femenino , Fluorodesoxiglucosa F18/análisis , Xenoinjertos , Humanos , Hipoxia/metabolismo , Inmunohistoquímica , Pulmón/química , Pulmón/efectos de los fármacos , Pulmón/metabolismo , Neoplasias Pulmonares/química , Neoplasias Pulmonares/metabolismo , Ratones , Ratones Desnudos , Oxígeno/farmacocinética , Oxígeno/farmacología , Tomografía de Emisión de Positrones , Distribución Tisular
15.
Angew Chem Int Ed Engl ; 58(44): 15772-15777, 2019 Oct 28.
Artículo en Inglés | MEDLINE | ID: mdl-31419007

RESUMEN

The anode oxygen evolution reaction (OER) is known to largely limit the efficiency of electrolyzers owing to its sluggish kinetics. While crystalline metal oxides are promising as OER catalysts, their amorphous phases also show high activities. Efforts to produce amorphous metal oxides have progressed slowly, and how an amorphous structure benefits the catalytic performances remains elusive. Now the first scalable synthesis of amorphous NiFeMo oxide (up to 515 g in one batch) is presented with homogeneous elemental distribution via a facile supersaturated co-precipitation method. In contrast to its crystalline counterpart, amorphous NiFeMo oxide undergoes a faster surface self-reconstruction process during OER, forming a metal oxy(hydroxide) active layer with rich oxygen vacancies, leading to superior OER activity (280 mV overpotential at 10 mA cm-2 in 0.1 m KOH). This opens up the potential of fast, facile, and scale-up production of amorphous metal oxides for high-performance OER catalysts.

16.
Adv Mater ; 31(23): e1900651, 2019 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-30985032

RESUMEN

Superelastic carbon aerogels have been widely explored by graphitic carbons and soft carbons. These soft aerogels usually have delicate microstructures with good fatigue resistance but ultralow strength. Hard carbon aerogels show great advantages in mechanical strength and structural stability due to the sp3 -C-induced turbostratic "house-of-cards" structure. However, it is still a challenge to fabricate superelastic hard carbon-based aerogels. Through rational nanofibrous structural design, the traditional rigid phenolic resin can be converted into superelastic hard carbon aerogels. The hard carbon nanofibers and abundant welded junctions endow the hard carbon aerogels with robust and stable mechanical performance, including superelasticity, high strength, extremely fast recovery speed (860 mm s-1 ), low energy-loss coefficient (<0.16), long cycle lifespan, and heat/cold-endurance. These emerging hard carbon nanofiber aerogels hold a great promise in the application of piezoresistive stress sensors with high stability and wide detection range (50 kPa), as well as stretchable or bendable conductors.

17.
Natl Sci Rev ; 6(2): 247-256, 2019 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-34691863

RESUMEN

Lithium metal is one of the most promising anode materials for high-energy-density Li batteries. However, low stability caused by dendrite growth and volume change during cycling hinders its practical application. Herein, we report an ingenious design of bio-inspired low-tortuosity carbon with tunable vertical micro-channels to be used as a host to incorporate nanosized Sn/Ni alloy nucleation sites, which can guide Li metal's plating/stripping and meanwhile accommodate the volume change. The pore sizes of the vertical channels of the carbon host can be regulated to investigate the structure-performance correlation. After compositing Li, the bio-inspired carbon host with the smallest pore size (∼14 µm) of vertical channels exhibits the lowest overpotential (∼18 mV at 1 mA cm-2), most stable tripping/plating voltage profiles, and best cycling stability (up to 500 cycles) in symmetrical cells. Notably, the carbon/Li composite anode is more rewarding than Li foil when coupled with LiFePO4 in full cells, exhibiting a much lower polarization effect, better rate capability and higher capacity retention (90.6% after 120 cycles). This novel bio-inspired design of a low-tortuosity carbon host with nanoalloy coatings may open a new avenue for fabricating advanced Li-metal batteries with high performance.

18.
Sci Adv ; 4(8): eaat7223, 2018 08.
Artículo en Inglés | MEDLINE | ID: mdl-30105307

RESUMEN

Woods provide bioinspiration for engineering materials due to their superior mechanical performance. We demonstrate a novel strategy for large-scale fabrication of a family of bioinspired polymeric woods with similar polyphenol matrix materials, wood-like cellular microstructures, and outstanding comprehensive performance by a self-assembly and thermocuring process of traditional resins. In contrast to natural woods, polymeric woods demonstrate comparable mechanical properties (a compressive yield strength of up to 45 MPa), preferable corrosion resistance to acid with no decrease in mechanical properties, and much better thermal insulation (as low as ~21 mW m-1 K-1) and fire retardancy. These bioinspired polymeric woods even stand out from other engineering materials such as cellular ceramic materials and aerogel-like materials in terms of specific strength and thermal insulation properties. The present strategy provides a new possibility for mass production of a series of high-performance biomimetic engineering materials with hierarchical cellular microstructures and remarkable multifunctionality.

19.
Adv Mater ; 30(25): e1707430, 2018 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-29744940

RESUMEN

SiOx is proposed as one of the most promising anodes for Li-ion batteries (LIBs) for its advantageous capacity and stable Li uptake/release electrochemistry, yet its practical application is still a big challenge. Here encapsulation of SiOx nanoparticles into conductive graphene bubble film via a facile and scalable self-assembly in solution is shown. The SiOx nanoparticles are closely wrapped in multilayered graphene to reconstruct a flake-graphite-like macrostructure, which promises uniform and agglomeration-free distribution of SiOx in the carbon while ensures a high mechanical strength and a high tap density of the composite. The composites present unprecedented cycling stability and excellent rate capabilities upon Li storage, rendering an opportunity for its anode use in the next-generation high-energy LIBs.

20.
Angew Chem Int Ed Engl ; 57(17): 4538-4542, 2018 04 16.
Artículo en Inglés | MEDLINE | ID: mdl-29469238

RESUMEN

Energy efficient buildings require materials with a low thermal conductivity and a high fire resistance. Traditional organic insulation materials are limited by their poor fire resistance and inorganic insulation materials are either brittle or display a high thermal conductivity. Herein we report a mechanically resilient organic/inorganic composite aerogel with a thermal conductivity significantly lower than expanded polystyrene and excellent fire resistance. Co-polymerization and nanoscale phase separation of the phenol-formaldehyde-resin (PFR) and silica generate a binary network with domain sizes below 20 nm. The PFR/SiO2 aerogel can resist a high-temperature flame without disintegration and prevents the temperature on the non-exposed side from increasing above the temperature critical for the collapse of reinforced concrete structures.

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