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1.
Int J Biol Macromol ; 167: 1479-1490, 2021 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-33221270

RESUMO

In this study, a versatile method for the manufacturing of chitosan-grafted porous poly (L-lactic acid) (P-PLLA) nanofibrous membrane by using polydopamine (PDA) as an intermediate layer has been developed. P-PLLA fibres were electrospun and collected as nano/micro fibrous membranes. Highly porous fibres could serve as a substrate for chitosan to adsorb heavy metal ions. Moreover, PDA was used to modify P-PLLA surface to increase the coating uniformity and stability of chitosan. Due to the very high surface area of P-PLLA membranes and abundant amine groups of both PDA and chitosan, the fabricated membranes were utilized as adsorbent for removal of copper (Cu2+) ions from the wastewater. The adsorption capability of Cu2+ ions was examined with respect to the PDA polymerization times, pH, initial metal ion concentration and time. Finally, the equilibrium adsorption data of chitosan-grafted membranes fitted well with the Langmuir isotherm with the maximum adsorption capacity of 270.27 mg/g.


Assuntos
Quitosana/química , Indóis/química , Metais Pesados/química , Nanofibras/química , Poliésteres/química , Polímeros/química , Purificação da Água/métodos , Adsorção , Cobre/química , Concentração de Íons de Hidrogênio , Íons/química , Cinética , Microscopia Eletrônica de Varredura , Modelos Estatísticos , Nanofibras/ultraestrutura , Porosidade , Espectrofotometria , Espectroscopia de Infravermelho com Transformada de Fourier , Propriedades de Superfície , Águas Residuárias/análise , Poluentes Químicos da Água/análise , Difração de Raios X
2.
Mitochondrial DNA B Resour ; 5(3): 2278-2279, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33367007

RESUMO

Syringa oblata Lindl. is a popular ornamental shrub with aroma compounds. Here, we sequenced and assembled the complete chloroplast genome of S. oblata. The complete chloroplast genome of S. oblata is 155,648 bp in length, containing a pair of inverted repeated (IRa and IRb) region of 25,732 bp that are separated by a large single copy (LSC) region of 86,247 bp, and a small single copy (SSC) region of 17,937 bp. A total of 132 functional genes were annotated, including 88 protein-coding genes, 36 tRNA genes, and eight rRNA genes. The Neighbour-joining phylogenetic tree based on complete chloroplast genomes suggested that S. oblata is most closely related to S. vulgaris.

3.
Mater Sci Eng C Mater Biol Appl ; 116: 111168, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32806301

RESUMO

In order to provide a favourable environment for living bone formation, it is an essential condition to grow bone-like apatite layer at the interface between the tissue-implant and its surrounding tissues. Inspired by the chemical composition and the nano porous structure of natural bones, we developed an ultrafast and accessible route to accelerate effectively the formation of bone-like apatite on the surface of porous poly(l-lactic acid)-hydroxyapatite (PLLA-HA) composite fibres in 5 times simulated body fluid (5SBF). The key of the method lays in successful exposure of HA nanoparticles on the surface of PLLA fibres by acetone treatment of electrospun PLLA-HA nano/micro fibres. The recrystallization of PLLA chains uncovers more HA nanoparticles on the surface of every fibre which provide nucleation sites for calcium and phosphate ions. After only 2 h of immersing in 5SBF, a full layer of apatite completely covered on the surface of porous PLLA-HA fibres. The results indicate that HA nanoparticles on porous fibre surface can accelerate the kinetic deposition of apatite on fibre surface. Biological in vitro cell culture with human osteoblast-like cell for up to 7 days demonstrates that the incorporation of HA nanoparticles on the surface of porous PLLA fibrous membranes leads to significant enhance osteoblast adhesion and proliferation. The route can open avenues for development of fibrous PLLA biomaterials for hard tissue repair and substitution.


Assuntos
Durapatita , Osteogênese , Apatitas , Humanos , Ácido Láctico , Poliésteres , Porosidade
4.
ACS Appl Mater Interfaces ; 11(22): 20037-20044, 2019 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-31071261

RESUMO

A paraffin microsphere-templated 3D porous EcoFlex sponge was prepared to selectively absorb oil or chemicals from water. The technology for producing this EcoFlex sponge does not need complicated synthesis processes or instruments, and the materials applied in this work are ecofriendly. Therefore, this sponge can be employed in the environmental field. EcoFlex sponges showed high hydrophobicity (contact angle = 140-143°) and oleophilicity. The developed sponge exhibits a porous three-dimensional framework inside with excellent internal connectivity, which contributes both better absorption capacity and faster absorption rate. For instance, the absorption capacity for chloroform can reach 3400 wt %. The absorption capacity of the sponge was optimized using different size of paraffin microspheres and these sponges exhibit relatively high absorption capacity in a short time (2 min). The volume of sponge expands in some oils and organic solvents: the increased volume capacity for hexane can reach 2200%. This sponge also has great recovery capability and durability; it keeps its original shape and absorption capacity after 15 cycles of oil absorption and compression.

5.
Medicine (Baltimore) ; 98(3): e14116, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30653136

RESUMO

RATIONALE: Madelung disease (MD), a rarely reported disease, also known as benign symmetric lipomatosis, a disorder resulting from alcoholic abuse. It's largely under-recognized and under-reported, possibly because of unawareness of the condition by physicians. PATIENT CONCERNS: A 45-year-old Chinese man presented with intermittent fatigue and abdominal distension and progressive bilateral breast enlargement. He has been a heavy drinker for ten years before onset of the disease with an average daily alcohol intake of more than 120 g/day. DIAGNOSIS: Due to the patient's symptoms, laboratory test results, radiographic findings, he was diagnosed with MD. INTERVENTIONS: We treated him with abstinence from alcohol and supportive therapy. OUTCOMES: The patient is now in stable condition, with improvement in symptoms during follow-up. LESSONS: Doctors, confronted with progressive bilateral breast enlargement in a patient with alcoholic liver disease, should be aware of the underreported MD. Recognition of this syndrome could help doctors establish diagnosis and emphasize the importance of alcohol abstinence as the mainstay of management.


Assuntos
Alcoolismo/complicações , Lipomatose Simétrica Múltipla/etiologia , Humanos , Masculino , Pessoa de Meia-Idade
6.
ACS Appl Mater Interfaces ; 11(49): 46261-46268, 2019 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-31718154

RESUMO

Ultrafine particulate aerosols less than 100 nm diffuse randomly in the air and are hazardous to the environment and human health. However, no technical standards or commercial products are available for filtering particle sizes under 100 nm yet. Here, we report the development of a porous poly(l-lactic acid) (PLLA) nanofibrous membrane filter with an ultra-high specific surface area via electrospinning and a post-treatment process. After PLLA fibres were electrospun and collected, they were treated by acetone to generate a blossoming porous structure throughout each individual fibre. Characterizations of morphology, crystallinity, and mechanical and thermal properties demonstrated that the porous structure can be attributed to the nonsolvent-induced spinodal phase separation during electrospinning and solvent-induced recrystallization during post treatment. The blossoming porous structure with high specific surface area contributed to excellent filtration efficiency (99.99%) for sodium chloride (NaCl) ultrafine aerosol particles (30-100 nm) with a low pressure drop (110-230 Pa). Notably, under 7.8 cm/s air flow rate, the membrane samples performed better for filtering smaller-sized aerosol particles than the larger ones when evaluated by the quality factor (0.07). Finally, this finding demonstrates that the electrospun membrane with a hierarchical pore structure and high specific surface area hold great potential in applications as air-filtering materials.

7.
Nat Commun ; 9(1): 5197, 2018 12 05.
Artigo em Inglês | MEDLINE | ID: mdl-30518870

RESUMO

Printed electronics offer a breakthrough in the penetration of information technology into everyday life. The possibility of printing electronic circuits will further promote the spread of the Internet of Things applications. Inks based on graphene have a chance to dominate this technology, as they potentially can be low cost and applied directly on materials like textile and paper. Here we report the environmentally sustainable route of production of graphene ink suitable for screen-printing technology. The use of non-toxic solvent Dihydrolevoglucosenone (Cyrene) significantly speeds up and reduces the cost of the liquid phase exfoliation of graphite. Printing with our ink results in very high conductivity (7.13 × 104 S m-1) devices, which allows us to produce wireless connectivity antenna operational from MHz to tens of GHz, which can be used for wireless data communication and energy harvesting, which brings us very close to the ubiquitous use of printed graphene technology for such applications.

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