Composite polymer electrolytes (CPEs) hold significant promise for solid-state batteries due to their ability to combine the benefits of inorganic fillers and polymer matrices. However, agglomeration of inorganic fill...
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A facile technique is herein reported to fabricate three-dimensional (3D) polymeric porous scaffolds with interior surfaces of a topographic microstructure favorable for cell adhesion. As demonstration, a well-known...
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A facile technique is herein reported to fabricate three-dimensional (3D) polymeric porous scaffolds with interior surfaces of a topographic microstructure favorable for cell adhesion. As demonstration, a well-known biodegradable polymer poly(lactide-co-glycolide) (PLGA) was employed as matrix. Under the porogen-leaching strategy, the large and soft porogens of paraffin were modified by colliding with small and hard salt particles, which generated micropits on the surfaces of paraffin spheres. The eventual PLGA scaffolds after leaching the modified porogens had thus interior surfaces of microscale roughness imprinted by those micropits. The microrough scaffolds were confirmed to benefit adhesion of bone marrow stromal cells (BMSCs) of rats and meanwhile not to hamper the proliferation and osteogenic differentiation of the cells. The insight and technique might be helpful for biomaterial designing in tissue engineering and regenerative medicine.
Ca(II) ions are added in the spinning dope to adjust the solidification rate of regenerated silk fibroin (RSF) solution during the wet-spinning process since Ca(II) ions are proved to be favorable to maintain th...
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Ca(II) ions are added in the spinning dope to adjust the solidification rate of regenerated silk fibroin (RSF) solution during the wet-spinning process since Ca(II) ions are proved to be favorable to maintain the stable silk fibroin network in our previous work. The results show that when Ca(II)/RSF ratios are 1/50 and 1/20, the resulted RSF fibers exhibit good performance with the breaking energy more than 70 kJ/kg. However, higher Ca(II)/RSF ratio (for example, 1/10) hinders the solidification of spinning dope and results in poor RSF fibers. These observations together with earlier papers from this laboratory confirm that to produce tough silk fibers the spinning conditions must allow sufficient time for the adjustment of silk fibroin molecular chains.
Sexual selection is thought to play a major role in the evolution of color due to the correlation between a signaler’s physiological state and the displayed *** such,researchers often investigate how color correlates...
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Sexual selection is thought to play a major role in the evolution of color due to the correlation between a signaler’s physiological state and the displayed *** such,researchers often investigate how color correlates to the quality of the ***,research on the relationship between color and individual quality is often taxonomically limited and researchers typically investigate how color phenotypes relate to one index of quality,such as a linear measure of body ***,we investigated the relationship among body size,claw size,claw muscle mass,lipid content,and the color of the claw in male fiddler crabs(Leptuca uruguayensis)which wield an exaggerated claw that varies in color from brown to *** hypothesized that if the color was correlated to one or more indices of male quality,the color displayed on the claws of male *** could be under sexual *** found *** claw color varies substantially among the individuals we ***,we did not find a correlation between claw color and indices of quality;neither brightness nor hue correlated to the indices of quality we *** findings suggest that claw color in *** is unlikely to have evolved to signal quality,but may instead function as a species identity or as a non-indicator sexual signal.
Given that conventional bulky electrochemical energy storage devices are too rigid and heavy to be considered wearable,developing fully integrated power systems is expected to accelerate the successful commercializati...
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Given that conventional bulky electrochemical energy storage devices are too rigid and heavy to be considered wearable,developing fully integrated power systems is expected to accelerate the successful commercialization of smart electronic *** great achievements have been made for fiber-shaped energy storage devices, there remain key challenges pertaining to their fabrication efficiency, scalability, and stability. Herein, a general and highly efficient method is developed to continuously fabricate supercapacitor fibers with lengths of kilometers at high production rate up to 118 m/h through a simple one-step wet spinning *** from the designed unique two-circle-in-one-circle architecture, the resulting supercapacitor fibers demonstrated high electrochemical stability even after being bended for 1 × 10~5 cycles. As a demonstration, these continuous supercapacitor fibers were further woven into a flexible power scarf for large-scale applications in wearable electronics. This simple and scalable fabrication process combined with the unique structure provides a general and effective paradigm to design other fiber-shaped devices like sensors, batteries,and solar cells.
The air voids that form when cement and aggregates are mixed with an aqueous polymer solution are not easily removed because they tend to be stabilized by the polymer. Antifoaming agents can be used to prevent air voi...
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The air voids that form when cement and aggregates are mixed with an aqueous polymer solution are not easily removed because they tend to be stabilized by the polymer. Antifoaming agents can be used to prevent air void formation, but they often cause problems of poor adhesion. An alternative approach is suggested for reducing air void formation in polymer-modified mortar, which is to pre-wet the cement and sand with water, and then add a concentrated polymer solution. The air content of a PVA-modified cement mortar prepared in this way was as low as 6%, which was lower than the 13% air content of the PVA-modified mortar with an antifoaming agent, and it was much lower than the 32% air content when a PVA solution was mixed with dry cement and sand. (C) 1997 Elsevier science Ltd.
Due to the mechanical mismatch between conventional rigid electronic devices and soft tissues at nature,a lot of interests have been attracted to develop flexible bioelectronics that work well both in vitro and in viv...
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Due to the mechanical mismatch between conventional rigid electronic devices and soft tissues at nature,a lot of interests have been attracted to develop flexible bioelectronics that work well both in vitro and in vivo. To this end, polymers that can be used for both key components and substrates are indispensable to achieve high performances such as high sensitivity and long-term stability for sensing *** we will summarize the recent advances on the synthesis of a variety of polymers, the design of typical architectures and the integration of different functions for the flexible bioelectronic devices. The remaining challenges and promising directions are highlighted to provide inspirations for the future study on the emerging flexible bioelectronics at end.
Amorphous multi-element materials offer unprecedented tunability in composition and properties, yet their rational design remains challenging due to the lack of predictive structure-property relationships and the vast...
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Stoichiometric silicon nitride has emerged as a widely used integratedphotonic material owing to its high index of refraction, nonlinear opticalproperties, and broad transparency window spanning visible to mid-IRfrequ...
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The influence of SiC particulate size on the age-hardening response of 2009 aluminium has been monitored utilizing hardness, electrical conductivity and differential scanning calorimetry. Ageing involved either two or...
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The influence of SiC particulate size on the age-hardening response of 2009 aluminium has been monitored utilizing hardness, electrical conductivity and differential scanning calorimetry. Ageing involved either two or three stages depending on the reinforcement size. For 2009 Al reinforced with 29 mu m SiCp, initial ageing consisted of GPB (Guinier Preston Baqaryatsky) I zone formation. Decreasing the particulate size to 4 mu m eliminated GPB I formation. This suppression of GPB I formation during ageing suggests that decreasing SiC size decreases the vacancy supersaturation following quenching by providing additional vacancy sinks at SiC/matrix interfaces. Subsequent ageing involved, at the larger reinforcement sizes, a transition with increasing time from GPB I zones to GPB Il-dislocation complexes. At smaller (4 mu m) reinforcement sizes, the formation of GPB Il-dislocation complexes occurs directly. Finally, the last stages of age hardening in all SiCp-reinforced composites examined consisted of heterogeneous nucleation of S'/S and GPB II --> S'/S transformation.
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