Electrospun material with bio-inspired ordered architectures and patterns is very interesting,yet remains a *** report here that nanofibrous mats with bird's nest patterned structures can be directly electrospun from...
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Electrospun material with bio-inspired ordered architectures and patterns is very interesting,yet remains a *** report here that nanofibrous mats with bird's nest patterned structures can be directly electrospun from chlorinated polypropylene solutions doped with an ionic *** solution viscosity and the ionic liquid content are two dominant factors to influence the topological morphology of the nanofibrous *** patterned structures can be further modulated by the collection time of electrospinning,the humidity of environment and the design of *** suggest the electrostatic repulsion between the residual charges of the mat surface and the upcoming nanofibers plays a key role in the formation of the bird's nest patterns.
The reinforcement of rubbers by nanoparticles is always accompanied with enhanced dissipation of mechanical energy upon large *** for solving the contradiction between improving reinforcement and reducing energy dissi...
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The reinforcement of rubbers by nanoparticles is always accompanied with enhanced dissipation of mechanical energy upon large *** for solving the contradiction between improving reinforcement and reducing energy dissipation for rubber nanocomposites have not been well *** carbon black(CB)filled isoprene rubber(IR)/liquid isoprene rubber(LR)blend nanocomposites with similar crosslink density(ve)are prepared and influence of LR on the strain softening behaviors including Payne effect under large amplitude shear deformation and Mullins effect under cyclic uniaxial deformation is *** introduction of LR could improve the frequency sensitivity of loss modulus and reduce critical strain amplitude for Payne effect and loss modulus at the low ***,tuning ve and LR content allows reducing mechanical hysteresis in Mullins effect without significant impact on the mechanical *** investigation is illuminating for manufacturing nanocomposite vulcanizates with balanced mechanical hysteresis and reinforcement effect.
Modulated-temperature differential scanning calorimetric and dynamic mechanical analyses and dielectric spectroscopy were used to investigate the glass transition of hydrated wheat gliadin powders with moisture absorp...
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Modulated-temperature differential scanning calorimetric and dynamic mechanical analyses and dielectric spectroscopy were used to investigate the glass transition of hydrated wheat gliadin powders with moisture absorption ranged from 2.30 db% to 18.21 db%. Glass transition temperature (Tg) of dry wheat gliadin was estimated according to the Gordon- Taylor equation. Structural heterogeneity at high degrees of hydration was revealed in dielectric temperature and frequency spectra. The activation energies (Ea) of the two relaxations were calculated from Arrhenius equation.
The surfaces and interfaces of biomaterials interact with the biological systems in multi-scale levels,and thereby influence the biological functions and comprehensive performance in vitro and in *** particular,a surf...
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The surfaces and interfaces of biomaterials interact with the biological systems in multi-scale levels,and thereby influence the biological functions and comprehensive performance in vitro and in *** particular,a surface promoting the selective adhesion and directional migration of desired types of cells in complex environment is extremely important in the repair and regeneration of tissues such as peripheral nerve and blood vessel,and long-term application of intracorporal devices such as intravascular ***,surface modification of biomaterials is a facile and effective method to achieve the desired cell-biomaterials *** this short review,recent advances on the surface modification of biomaterials to regulate selective cell adhesion and migration are briefly *** particular,the surface properties of biomaterials are manipulated via the convenient introduction of amino groups to the ester-based polymers,the formation of polyelectrolyte multilayers,and the fabrication of topology and gradient cues,etc.,followed by the association of chemical and biological signals such as collagen,heparin,hyaluronic acid,peptides and cell growth *** selective adhesion and directional migration of various types of cells such as endothelial cells(ECs),smooth muscle cells(SMCs),hepatocytes and Schwann cells(SCs)are achieved over the competitive counterpart cells by the use of cell-resisting substances and cell-selective motifs on gradient substrates in most *** advances on cell behaviors in three-dimensional(3D)ceH-extracellular matrix(ECM)-mimicking substrates are also reviewed.
The stimuli-responsive nanomaterials are gaining more and more interest in the biological field,including cell imaging and biosensing etc. Nanomaterials in response to the bio-relevant stimuli(i.e., p H, enzymes and o...
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The stimuli-responsive nanomaterials are gaining more and more interest in the biological field,including cell imaging and biosensing etc. Nanomaterials in response to the bio-relevant stimuli(i.e., p H, enzymes and other bioactive molecules) can be utilized to enhance imaging(i.e., optical imaging, MRI, and multi-mode imaging) sensitivity via disease site-specific delivery and controlled release, which helps to diagnose cancer at an early stage or to monitor progression during treatment. In the triggered responsive process, smart nanomaterials undergo changes in physiochemical properties that can cause cytotoxicity or influence on cell functions due to the interactions between nanomaterials and cells. In order to promote the design and fabrication of effective platforms for therapeutics and diagnostics, special attention should be paid to these effects. By taking the advantages of intracellular stimuli, the controlled self-assembly in living cells can be achieved, which has been used for various in situ detections and insights into biological self-assembly. In this review, the recent advances in cell imaging, cytotoxicity and self-assembly of intracellular stimuli-responsive nanomaterials are summarized. Some principles for the further design and applications of intracellular stimuli-responsive nanomaterials and future perspectives are discussed.
In this paper,crystallization kinetics of a series of ethylene-propylene copolymers prepared by living polymerization coordination catalyzed by a fluorinated bis(phenoxyimine)Ti catalyst(FI-EP copolymers)was studied,a...
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In this paper,crystallization kinetics of a series of ethylene-propylene copolymers prepared by living polymerization coordination catalyzed by a fluorinated bis(phenoxyimine)Ti catalyst(FI-EP copolymers)was studied,and was compared with that of ethylene-propylene copolymers prepared by a conventional Ziegler-Natta catalyst(ZN-EP copolymers).It is found that,the Avrami exponent and the crystallization rate constant of the FI-EP and ZN-EP copolymer show similar dependence on crystallization temperature,but t...
The novel microgels, poly[di(ethylene glycol) methyl ether methacrylate-co-2-methoxyethyl acrylate] poly(DEGMMA-co-MEA) microgels, were synthesized. The poly(DEGMMA-co-MEA) microgels were thermo-sensitive and ex...
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The novel microgels, poly[di(ethylene glycol) methyl ether methacrylate-co-2-methoxyethyl acrylate] poly(DEGMMA-co-MEA) microgels, were synthesized. The poly(DEGMMA-co-MEA) microgels were thermo-sensitive and exhibited a volume phase transitive temperature(VPTT) of 14–22 ℃. The incorporation of hydrophobic comonomer MEA shifted the VPTT of poly(DEGMMA-co-MEA) microgels to lower temperatures. The interfacial interaction of poly(DEGMMA-co-MEA) microgels and three model proteins, namely fibrinogen, bovine serum albumin and lysozyme, was investigated by quartz crystal microbalance(QCM). An injection sequence of "microgel-after-protein" was then established for the real-time study of the interaction of proteins and the microgels at their swollen and collapsed states by using QCM technique. The results indicated that the interfacial interaction of poly(DEGMMA-co-MEA) microgels and adsorbed protein layers was mainly determined by the electrostatic interaction. Because poly(DEGMMA-co-MEA) microgels were negatively charged in Tris-HCl buffer solution(pH = 7.4), the microgels did not adsorb on negatively charged fibrinogen and bovine serum albumin layers but strongly adsorbed on positively charged lysozyme layer. Stronger interaction between lysozyme and the microgels at collapsed state(i.e. at 37 ℃) was observed. Furthermore, the incorporation of MEA might weaken the interaction between poly(DEGMMA-co-MEA) microgels and proteins.
It is crucial to develop flexible and wearable electronic devices that have attracted tremendous interest due to their merits on compactness,flexibility and high capacitive *** we report the continuously ordered macro...
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It is crucial to develop flexible and wearable electronic devices that have attracted tremendous interest due to their merits on compactness,flexibility and high capacitive *** we report the continuously ordered macroscopic poly(ionic liquid)-graphene fibers by wet spinning method via liquid crystal assembly for supercapacitor *** fabricated all-solid-state supercapacitors exhibited a high areal capacitance(268.2 mF cm 2)and volumetric capacitance(204.6 F cm 3)with an outstanding areal energy density(9.31μWh cm-2)and volumetric energy density(8.28 mWh cm-3).The fiber supercapacitors demonstrated exceptional cycle life for straight electrodes of about 10,000 cycles(94.2%capacitance retention)and flexibility at different angles(0°,45°,90°,180°)along with a good flexible cycling stability after 6000 cycles(92.7%capacitance retention).To date,such a novel poly(ionic liquid)-graphene fiber supercapacitors would be a new platform in real-time flexible electronics.
Organic field-effect transistors are of great importance to electronic *** the emergence of various preparation techniques for organic semiconductor materials,the device performance has been improved *** all of the or...
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Organic field-effect transistors are of great importance to electronic *** the emergence of various preparation techniques for organic semiconductor materials,the device performance has been improved *** all of the organic materials,single crystals are potentially promising for high performances due to high purity and well-ordered molecular *** on organic single crystals,alignment and patterning techniques are essential for practical industrial application of electronic *** this review,recently developed methods for crystal alignment and patterning are described.
The general characteristics of the active center of the catalysts(including zinc-cobalt(III) double metal cyanide complex [Zn-Co(Ⅲ) DMCC]) for the copolymerization reaction of carbon dioxide(CO2) with epoxide...
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The general characteristics of the active center of the catalysts(including zinc-cobalt(III) double metal cyanide complex [Zn-Co(Ⅲ) DMCC]) for the copolymerization reaction of carbon dioxide(CO2) with epoxide are summarized. By comparing the active center, catalytic performance of the Zn-Co(Ⅲ) DMCC(and other catalysts) with HCAII enzyme in the organism for activating CO2(COS and CS2), we proposed that the metal-hydroxide bond(M-OH), which is the real catalytic center of human carbonic anhydride Ⅱ(HCAⅡ), is also the catalytic(initiating) center for the copolymerization. It accelerates the copolymerization and forms a closed catalytic cycle through the chain transfer reaction to water(and thus strictly meets the definition of the catalyst). In addition, the metal-hydroxide bond catalysis could well explain the oxygen/sulfur exchange reaction(O/S ER) in metal(Zn, Cr)-catalyzed copolymerization of COS(and CS2) with epoxides. Therefore, it is very promising to learn from HCAⅡ enzyme to develop biomimetic catalyst for highly active CO2/epoxide copolymerization in a well-controlled manner under mild conditions.
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