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.
Infectious of hepatitis c viruses(HcVs)lead to hepatic fibrosis,cirrhosis even *** rapid and sensitive diagnostic method for HcV is of great *** on the host-and-guest interaction between cucurbit[7]uril(cB[7])and meth...
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Infectious of hepatitis c viruses(HcVs)lead to hepatic fibrosis,cirrhosis even *** rapid and sensitive diagnostic method for HcV is of great *** on the host-and-guest interaction between cucurbit[7]uril(cB[7])and methylene blue(MB),a cB[7]-graphene nano-composite(cB[7]-N3-GO)is raised for the electrochemical detection of HcV *** method is able to linearly detect the HcV nucleic acid in the range of 0.2—10 nmol/L with detection limit as low as 160.4 pmol/*** proposed detection strategy is able to discriminate the lb and 6k subtypes of HcV and has a prospective potential in the blood screen for HcV in clinical diagnosis.
We describe our implementation of c and Fortran preprocessors for the FPS T-series hypercube. The target of these preprocessors is the occam I language. We provide a brief overview of the INMOS transputer and the Weit...
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We describe our implementation of c and Fortran preprocessors for the FPS T-series hypercube. The target of these preprocessors is the occam I language. We provide a brief overview of the INMOS transputer and the Weitek vector processing unit (VPU). These two units comprise one node of the T-series. Some depth of understanding of the VPU is required to fully appreciate the problems encountered in generating vector code. These complexities were not fully appreciated at the outset. The occam I language is briefly described. We focus on only those aspects of occam I which differ radically from c. The transformations used to preprocess c into occam I are discussed in detail. The special problems with the VPU both in terms of its (non)interface with occam I and in dealing with numerical programs is discussed separately. A lengthy discussion on the special techniques required for compilation is provided. c and Fortran are simply incompatible with the occam I model. We provide a catalogue of problems encountered. We emphasize that these problems are not so much with occam I but with preprocessing to occam I. We feel the cSP and occam I models are quite good for distributed processing. The ultimate message from this work should be seen in a larger context. Several languages-such as Ads and Modula-2-are being touted as the standards for the 1990s. These languages severely restrict parallel programming style;this may make saving dusty decks by preprocessing an impossibility.
In order to investigate the effects of preform structures on the mechanical and ablation properties of c/Zrc-Siccomposites, 3D4X, 3D5X and 3DZcc/Zrc-Siccomposites were fabricated with the same process. The mechanic...
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In order to investigate the effects of preform structures on the mechanical and ablation properties of c/Zrc-Siccomposites, 3D4X, 3D5X and 3DZcc/Zrc-Siccomposites were fabricated with the same process. The mechanical and ablation properties of 3D4X, 3D5X, and 3DZcc/Zrc-Siccomposites were investigated. Results showed that the tensile strength (122.26 MPa) and bending strength (233.29 MPa) of 3D5X c/Zrc-Siccomposites were the largest, followed by the tensile strength (112.79 MPa) and bending strength (203.03 MPa) of 3DZccomposites and the tensile strength (86.22 MPa) and bending strength (137.59 MPa) of 3D4X composites. The mechanical properties of c/Zrc-Siccomposites were mainly related to the fiber content in the axis direction and matrix compactness. In terms of ablation properties, 3DZcc/Zrc-Siccomposites acted out the worst performance (the linear ablation rates of 0.0293 mm/s and the mass ablation rates 0.00766 g/s), followed by 3D4X composites (the linear ablation rates of 0.0276 mm/s and the mass ablation rates 0.00683 g/s) and 3D5X composites (the linear ablation rates of 0.0175 mm/s and the mass ablation rates 0.00653 g/s), respectively, which were mainly due to the specific ablation angles, thermal conductivities, and ablation oxides contents caused by fiber volume fraction, braided angles, and other forming parameters.
The appropriate assessment of mechanical properties is essential to design ceramic matrix composites. The size effect of strength plays a key role for the material understanding and the transfer from lab-scale samples...
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The appropriate assessment of mechanical properties is essential to design ceramic matrix composites. The size effect of strength plays a key role for the material understanding and the transfer from lab-scale samples to components. In order to investigate the size effect for carbon fiber-reinforced silicon carbon (c/c-Sic) under tensile load, a tensile testing with a minimum of deviation from the pure tensile loading is necessary. Hence, a hybrid edge/face-loading test device for self-alignment and centering of c/c-Sic tensile samples was developed, evaluated and proved to ensure pure tensile load. The mechanical analysis of more than 190 samples with two different cross-sections fabricated from the same material population revealed no significant difference in tensile strength. Although the volume under load was increased from 129 to 154 mm3, the tensile strengths of 162 +/- 7 and 164 +/- 6 MPa did not change. These results are discussed regarding the weakest link and energetic size effect approaches.
Folic acid (FA) plays a vital role in central metabolism, including the one carbon cycle, nucleotide, and amino acid biosynthesis. The development of sensitive, accurate analytical methods to measure FA intermediates ...
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Folic acid (FA) plays a vital role in central metabolism, including the one carbon cycle, nucleotide, and amino acid biosynthesis. The development of sensitive, accurate analytical methods to measure FA intermediates in tissues is critical to understand their biological roles in diverse physiological and pathological contexts. Here, we developed a highly sensitive method for the simultaneous quantification of FA intermediates in the nematode caenorhabditis elegans as a model to dissect metabolic networks. The method was further validated by analyzing the worm folate pool upon RNAi knockdown of the dihydrofolate reductase gene dhfr-1. comparative mass spectrometry behavior of the FA analogs using two different ion sources, electrospray ionization (ESI) and atmospheric pressure chemical ionization (APcI), revealed ESI-MS/MS to be more sensitive, but APcI-MS provided more detailed structure inferences, which can elucidate chemical investigation and synthesis of FA analogs. Finally, we report on the use of in vitro oxidation coupled with high-resolution mass spectrometry as a tool to discover new endogenous FA derivatives in the nematode.
The synergy in cdMoO 4 /MoO 3 catalysts has been investigated in selective oxidation of c 4 hydrocarbons. Both of the pure phases, MoO 3 and cdMoO 4 , as well as the two-phase catalyst have been characterized using X-...
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The synergy in cdMoO 4 /MoO 3 catalysts has been investigated in selective oxidation of c 4 hydrocarbons. Both of the pure phases, MoO 3 and cdMoO 4 , as well as the two-phase catalyst have been characterized using X-ray diffraction, BET surface area measurement, scanning electron microscopy and laser Raman spectroscopy. Oxidation studies performed over the cdMoO 4 /MoO 3 catalyst and its pure-phase constituents, using both 1-butene and 1,3-butadiene as feed material, show that the two-phase catalyst had a higher selectivity to maleic anhydride than either of the pure phases. This synergistic effect is similar to the one previously observed over MnMoO 4 /MoO 3 catalysts.
This is the first empirical study of the use of the c macro preprocessor, cpp. To determine how the preprocessor is used in practice, this paper analyzes 26 packages comprising 1.4 million lines of publicly available ...
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This is the first empirical study of the use of the c macro preprocessor, cpp. To determine how the preprocessor is used in practice, this paper analyzes 26 packages comprising 1.4 million lines of publicly available ccode. We determine the incidence of c preprocessor usage-whether in macro definitions, macro uses, or dependences upon macros-that is complex, potentially problematic, or inexpressible in terms of other c or c++ language features. We taxonomize these various aspects of preprocessor use and particularly note data that are material to the development of tools for c or c++, including translating from c to c++ to reduce preprocessor usage. Our results show that, while most cpp usage follows fairly simple patterns, an effective program analysis tool must address the preprocessor. The intimate connection between the c programming language and cpp, and cpp's unstructured transformations of token streams often hinder both programmer understanding of c programs and tools built to engineer c programs, such as compilers, debuggers, call graph extractors, and translators. Most tools make no attempt to analyze macro usage, but simply preprocess their input, which results in a number of negative consequences;an analysis that takes cpp into account is preferable, but building such tools requires an understanding of actual usage. Differences between the semantics of cpp and those of ccan lead to subtle bugs stemming from the use of the preprocessor, but there are no previous reports of the prevalence of such errors. Use of c++ can reduce some preprocessor usage, but suck usage has not been previously measured. Our data and analyses shed light on these issues and others related to practical understanding or manipulation of real c programs. The results are of interest to language designers, tool writers, programmers, and software engineers.
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