Excessive discharge of toxic dyes is detrimental to ecological system and human health. Therefore, an effective photocatalyst must be designed and developed to degrade dyes from wastewater. Herein, a novel one-dimensi...
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Excessive discharge of toxic dyes is detrimental to ecological system and human health. Therefore, an effective photocatalyst must be designed and developed to degrade dyes from wastewater. Herein, a novel one-dimensional (1D) flower-like recoverable ZnFe2O4/c/MnO2/BiOI magneticcomposite photocatalyst was synthesized via electrospinning technique combined with hydrothermal method. The photocatalytic activities of composite photocatalyst were evaluated by degrading methyl orange (MO) and Rhodamine B (RhB) under simulated light irradiation. The efficiency of ZnFe2O4/c/MnO2/BiOI photocatalyst in visible light for 150 min reached 91% (MO) and 120 min reached 94% (RhB). Moreover, the degradation rate of MO still remained 78% after five cycles. The design of 1D magnetic flower-like composite provided a new strategy for preparing photocatalysts possessing excellent photocatalytic efficiency and cyclic stability.
c/MgO composite powders were prepared by combustion synthesis using magnesium oxalate and magnesium powders as raw materials. The phase composition and microstructure of the composite powders were investigated by X-ra...
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c/MgO composite powders were prepared by combustion synthesis using magnesium oxalate and magnesium powders as raw materials. The phase composition and microstructure of the composite powders were investigated by X-ray diffraction (XRD), field-emission scanning electron microscopy/energy dispersive spectroscopy (FESEM/EDS), high-resolution transmission electron microscopy (HRTEM) and Raman spectroscopy. The synthetic mechanism was explored through TG-FTIR and combustion front quenching techniques. It was found that the c/MgO composite powders contained a large quantity of MgO nanofibers. When the molar ratio of magnesium oxalate and magnesium was 1:4, the carbon content of the product reached a maximum of 9.45 wt %. In the composite powders, cubic MgO particles were encapsulated by a thin carbon layer, and there was a tiny gap between MgO and the carbon layer;a large number of MgO nanofibers with aspect ratios of 80?100 were found. The cubic MgO particles of the products are the direct decomposition of Mgc2O4, and the MgO nanofibers are the reaction product of gaseous Mg and cO2/cO at high temperature. Meanwhile, the carbon deposited on the MgO particles can inhibit the grain growth of MgO particles and result in the refinement of MgO particles. The uniform dispersion of carbon and the weak c/MgO interface combine, making the composite powders a potential additive for low-carbon MgO?c refractories with excellent thermal shock resistance.
In order to study the effects of temperature on the material behavior of Liquid Silicon Infiltration (LSI) based continuous carbon fiber reinforced silicon carbide (c/c-Sic), the mechanical properties at room temperat...
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In order to study the effects of temperature on the material behavior of Liquid Silicon Infiltration (LSI) based continuous carbon fiber reinforced silicon carbide (c/c-Sic), the mechanical properties at room temperature (RT) in in-plane and out-of-plane directions are summarized and the tensile properties of c/c-Sic were then determined at high temperature (HT) 1200 degrees c and 1400 degrees c under quasi static and compliance loading. The stressstrain response of both HT tests is similar and almost no permanent strain can be observed compared to the RT, which can be explained through the relaxation of residual thermal stresses and the crack distribution under various states. The different fracture mechanisms are confirmed by the analysis of fracture surface. Furthermore, based on the analysis of hysteresis measurements at RT, a modeling approach for the prediction of material behavior at HT has been developed and a good agreement between test and modeling results can be observed.
AbstractRecent advances in hardware technology have made the construction of multiprocessor systems economically feasible. This paper describes a new programming language (concurrent c) suitable for distributed system...
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AbstractRecent advances in hardware technology have made the construction of multiprocessor systems economically feasible. This paper describes a new programming language (concurrent c) suitable for distributed systems which are networks of loosely connected processors, each with its own local storage. concurrent c is the extended version of the programming language c, incorporating features for parallel processing and interprocess communications.
The isothermal oxidation behavior of Ti-48Al-1.3Fe-1.1V-0.3B (at.%) implanted with c, Nb or c + Nb was investigated at 1173 K for 349.2 ks in air. Dose was 3.0 x 10(21) ions per m(2) and the acceleration voltage was 5...
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The isothermal oxidation behavior of Ti-48Al-1.3Fe-1.1V-0.3B (at.%) implanted with c, Nb or c + Nb was investigated at 1173 K for 349.2 ks in air. Dose was 3.0 x 10(21) ions per m(2) and the acceleration voltage was 50 kV for each element. The purpose of this study is to improve the high-temperature oxidation resistance of the alloy by suitable implantation process and clarify the effects of c, Nb and their interaction on the formation of the oxide scale. Thermobalance, auger electron spectroscopy (AES) and scanning electron microscopy (SEM) were used to characterize the oxidation behavior and the scale structure, It was found that the c implantation is harmful to the long-term oxidation resistance, the Nb implantation significantly decreases the oxidation rate, and the c + Nb implantation can further improve the beneficial effect of the Nb implanted alloy and thus gives the best oxidation resistance. It was also found that for the c implantation, the c rich layer can act as a barrier to the inward diffusion of O in the early stage of the oxidation, but this effect will disappear after oxidation for about 3.6 ks due to the fast consumption of c. The presence of Nb can promote the formation of an Al enriched layer in the external scale. The co-existence of Nb and c would enhance their respective stability remained in the external scale or substrate with high peak concentration and thus prolong and intensify their respective beneficial effects. The significant improvement of the oxidation resistance of the c + Nb combined implantation is attributed to the above respective c and Nb beneficial effect and their interaction during the oxidation. (c) 2001 Elsevier Science B.V. All rights reserved.
The multi-directional laminate ccF800H/Ac631 bismaleimide composite material was exposed for a long time under the thermal-cycling environment (-60 degrees c similar to+180 degrees c), and the mass loss rate, FTIR spe...
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The multi-directional laminate ccF800H/Ac631 bismaleimide composite material was exposed for a long time under the thermal-cycling environment (-60 degrees c similar to+180 degrees c), and the mass loss rate, FTIR spectra, DMA, tensile strength were tested. The fatigue stress level was determined according to the tensile strength and the fatigue performance of the before and after the thermal-cycling environment was tested. Macroscopic visual inspection and ultrasonicc-scan were used to characterize and analyze the fatigue damage of composite materials. The results show that with the increase in the number of thermal cycles, the mass loss of the composite material started with increased rapidly and then basically flat. The c/BMI composites underwent obvious thermal oxygen aging. After thermal-cycling, it would lead to changes in dynamic mechanical properties by a certain degree of post-curing, physical aging, and local interface debonding in composite materials. With the thermal cycles increased the composite material tensile strength first increased slightly and then decreased rapidly. After 300 thermal cycles, the composite materials occurred slightly damaged, and the fatigue life was apparently reduced compared with the original state. The fatigue failure modes of composite materials are mainly fiber fracture and multi-directional laminate delamination. At high stress levels, the stiffness of the specimen after thermal-cycling are lower decrease compared with original specimens, more stress levels would lead to more II stage rate of stiffness decline, and stiffness degradation curve and hysteretic energy recovery curve had enough effect to characterize damage effect of material environment induced by thermal-cycling environment factors.
The c programming language is a foundational technology for modern computing with millions of lines of code implementing everything from hobby projects to commercial operating systems. This installation base and the p...
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The c programming language is a foundational technology for modern computing with millions of lines of code implementing everything from hobby projects to commercial operating systems. This installation base and the programmers producing it represent a massive software engineering investment spanning decades and likely to continue for decades more. Nevertheless, c, which was first standardized almost 30 years ago, lacks many features that make programming in more modern languages safer and more productive. The goal of the c for all project (pronounced "c for all") is to create an extension of c that provides modern safety and productivity features while still ensuring strong backward compatibility with c and its programmers. Prior projects have attempted similar goals but failed to honor the c programming style;for instance, adding object-oriented or functional programming with garbage collection is a nonstarter for many c developers. Specifically, c for all is designed to have an orthogonal feature set based closely on the c programming paradigm, so that c for all features can be added incrementally to existing ccode bases, and c programmers can learn c for all extensions on an as-needed basis, preserving investment in existing code and programmers. This paper presents a quick tour of c for all features, showing how their design avoids shortcomings of similar features in c and other c-like languages. Experimental results are presented to validate several of the new features.
An interwoven hollow fiber structured mesoporous NiO catalyst doped with c, S was fabricated by the vacuum impregnation and thermal decomposition methods using eggshell membrane as template. The structure of the catal...
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An interwoven hollow fiber structured mesoporous NiO catalyst doped with c, S was fabricated by the vacuum impregnation and thermal decomposition methods using eggshell membrane as template. The structure of the catalyst was characterized by X-ray diffraction, thermo-gravimetric analysis, scanning electron microscopy, transmission electron microscopy, X-ray photoelectron spectroscopy, and specific surface area test. Under a high vacuum condition, the synthesized NiO material has a better interwoven fiber and mesoporous structure, which effectively increases the specific surface area of the material. c and S were doped into NiO via eggshell membrane pyrolysis, which then formed c-OH and SO42- species on the surface of the material. The electrocatalytic performance of the catalyst for the oxidation of methanol in alkaline solution was studied by cyclic voltammetry and chronoamperometry. The c, S doped mesoporous NiO material exhibits much higher catalytic efficiency and anti-poisoning ability than that of NiO nanoparticles due to the synergisticcatalysis of NiO and doping c-OH and SO42- species. Graphic abstract
c-reactive protein (cRP) binds with high affinity to fibronectin (Fn), a major component of the extracellular matrix (EcM), but at physiological pH the binding is inhibited by calcium ions (ca2+). Because cRP circulat...
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c-reactive protein (cRP) binds with high affinity to fibronectin (Fn), a major component of the extracellular matrix (EcM), but at physiological pH the binding is inhibited by calcium ions (ca2+). Because cRP circulates in the blood in ca2+-bound form, the occurrence of cRP-Fn interactions in vivo has been doubtful. To define the basis of inhibition of cRP-Fn interaction by ca2+ at pH 7.0, we hypothesized that Fn-binding site on cRP consisted of amino acids co-ordinating ca2+. Site-directed mutagenesis of amino acids co-ordinating ca2+ drastically decreased the binding of cRP to Fn, indicating that the ca2+-binding site indeed formed the Fn-binding site. To determine the requirements for possible interaction between ca2+-bound cRP and Fn, we investigated inhibition of cRP-Fn interaction by ca2+ as a function of pH. ca2+ did not inhibit binding of cRP to Fn at pH 6.5 and lower. The contrasting Fn binding properties of cRP at physiological and mildly acidic pH indicated that the interaction of ca2+-bound cRP with Fn was controlled by pH. We conclude that the inhibition of binding of cRP to Fn by ca2+ at pH 7.0 is a mechanism to prevent cRP-Fn interactions under normal conditions. cRP, in its ca2+-bound state, is capable of binding Fn but only at the inflammatory sites and tumors with low pH. cRP, Fn, and the EcM all have been implicated in cancer. Taken together our data raise the possibility that cRP-Fn interactions may change the architecture of EcM to modify the development of tumors.
The dependence of import of chicken heart apocytochrome c on its transformation to holoform by heme attachment was studied. Results showed that there was no difference in the translocation of apocytochrome c across th...
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The dependence of import of chicken heart apocytochrome c on its transformation to holoform by heme attachment was studied. Results showed that there was no difference in the translocation of apocytochrome c across the mitochondrial membrane in the presence or absence of hemin + dithionite. Furthermore, two heme unattached mutants (H18D, c17S) were prepared, which could still be accumulated in mitochondria, but their import velocity was obviously reduced.
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