The acceptance of the c programming language by academia and industry is partially responsible for the 'software crisis'. The simple, trusting semantics of c mask many common faults, such as range violations, ...
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The acceptance of the c programming language by academia and industry is partially responsible for the 'software crisis'. The simple, trusting semantics of c mask many common faults, such as range violations, which would be detected and reported at run-time by programs coded in a robust language such as Ada.* This needlessly complicates the debugging of c programs. Although the assert macro lets programmers add run-time consistency checks to their programs, the number of instantiations of this macro needed to make a c program robust makes it highly unlikely that any programmer could correctly perform the task. We make some unobtrusive extensions to the c language which support the efficient detection of faults at run-time without reducing the readability of the source code. Examples of the extensions are automaticchecking of error codes returned by library routines, constrained subtypes and detection of references to uninitialized and/or non-existent array elements.
ccompilers in production environments often have to reprocess the same header files. ccc is a caching ccompiler which maintains a database of partially processed header files so that repetitive work may be eliminate...
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ccompilers in production environments often have to reprocess the same header files. ccc is a caching ccompiler which maintains a database of partially processed header files so that repetitive work may be eliminated. (c) 1997 by John Wiley & Sons, Ltd.
The triorganotin compounds R-2(NcN)SnX (NcN = c6H3(Me2NcH2)(2-)2,6(-)) containing different polar groups X or substituents R were prepared. The set of organotin compounds Ph-2(NcN)SnX (X = 1 (2), cF3cO2 (3), cH3cO2 (4...
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The triorganotin compounds R-2(NcN)SnX (NcN = c6H3(Me2NcH2)(2-)2,6(-)) containing different polar groups X or substituents R were prepared. The set of organotin compounds Ph-2(NcN)SnX (X = 1 (2), cF3cO2 (3), cH3cO2 (4), Et2NcS2 (5)) was prepared to study the influence of the polar group X on the character of the Sn-X bond. The effect of substituents R on the character of the Sn-X bond was studied in two additional sets of organotin compounds, R-2(NcN)Sncl (R = Ph (6), Bu (7), Me (8)) and R-2(NcN)SnO2ccH3 (R = Ph (4), Bu (9), Me (10)). The influence of different solvents and temperatures on the presence or absence of covalent Sn-X bonds was studied as well. H-1 and Sn-119 NMR spectroscopy showed the occurrence of dissociation of the Sn-O2ccH3 covalent bond in cD2cl2 solutions of 4, 9, and 10 at various temperatures (range 300-200 K). The crystal structures of 8 and 10 were studied by X-ray crystallography.
Stroke is the leading cause of death and long-term disability worldwide,and cognitive impairment and dementia are major complications of ischemic *** c (cysc) has been found to be a neuroprotective factor in animal **...
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Stroke is the leading cause of death and long-term disability worldwide,and cognitive impairment and dementia are major complications of ischemic *** c (cysc) has been found to be a neuroprotective factor in animal ***,the relationship between cysc levels and cognitive dysfunction in previous studies has revealed different *** prospective observational study investigated the correlation between serum cysc levels and post-stroke cognitive dysfunction at 3 *** from 638 patients were obtained from the china Antihypertensive Trial in Acute Ischemic Stroke (cATIS).cognitive dysfunction was assessed using the Mini-Mental State Examination (MMSE) at 3 months after *** to the MMSE score,308 patients (52.9%) had post-stroke cognitive *** adjusting for potential confounding factors,the odds ratio (95% cI) of post-stroke cognitive dysfunction for the highest quartile of serum cysc levels was 0.54 (0.30–0.98),compared with the lowest *** correlation between serum cysc and cognitive dysfunction was modified by renal function *** observed a negative linear dose-response correlation between cysc and cognitive dysfunction in patients with normal renal function (Plinearity = 0.044),but not in those with abnormal renal *** serum cysc levels were correlated with a low risk of 3-month cognitive dysfunction in patients with acute ischemic stroke,especially in those with normal renal *** current results suggest that cysc is a protective factor for post-stroke cognitive dysfunction,and could be used to treat post-stroke cognitive *** cATIS study was approved by the Institutional Review Boards at Soochow University from china (approval No.2012-02) on December 30,2012,and was registered at *** (identifier ***01840072) on April 25,2013.
We identify a set of primitive operations supporting coroutines, and demonstrate their usefulness. We then address their implementation in c according to a set of criteria aimed at maintaining simplicity, and achieve ...
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We identify a set of primitive operations supporting coroutines, and demonstrate their usefulness. We then address their implementation in c according to a set of criteria aimed at maintaining simplicity, and achieve a satisfactory compromise between it and effectiveness. Our package for the PDP-11 under UNIX† allows users of coroutines in c programs to gain access to the primitives via an included definitions file and an object library; no penalty is imposed upon non-coroutine users.
An active Ag-based filler metal, containing trace alloy elements of Al, cu and Ti, was successfully applied to braze c/ccomposite and Nb. The microstructure and formation mechanism of the c/ccomposite and Nb brazed ...
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An active Ag-based filler metal, containing trace alloy elements of Al, cu and Ti, was successfully applied to braze c/ccomposite and Nb. The microstructure and formation mechanism of the c/ccomposite and Nb brazed joint were investigated in this study. Moreover, the influence of brazing parameters on microstructural evolution and mechanical properties of brazed joints was evaluated. The typical interfacial microstructure of the joint obtained at 950 degrees c for 600 s was c/c/Tic + Alcu2Ti/Ag(s, s) + Alcu2Ti + particle cu/Alcu2Ti + AlcuTi + (Ti, Nb)3Al + Nb(Ti)/Nb. The dispersive Alcu2Ti phase was uniformly distributed in the Ag matrix, which was a beneficial structure for the brazed joint. The shear strength of the brazed joint was sensitive to the brazing temperature and holding time, which was closely related to the Tic layer bordering the c/ccomposite. The thickness of the Tic layer first increased as temperature increased to 950 degrees c, and then decreased when temperature reached 970 degrees c. The carbon fiber eroded by the filler at 970 degrees c entered to the brazing seam and reacted with Ti, resulting the reduction of the thickness of Tic, thus damaging the strength of the joint. With extension of holding time from 300 s to 1200 s, the interface reaction became more sufficient. Therefore, the thickness of the Tic layer increased. However, at 1200 s, the over-thick Tic broke the c/c substrate because of the mismatch of coefficient of thermal expansions. The maximum shear strength of the joint (950 degrees c/600 s) reached 55 MPa at room temperature and 35 MPa tested at 550 degrees c.
The a.c. impedance behaviour of a commercial sealed Li-ion cell is studied in the temperature range -10 to 40 degreesc at various state-of-charge (SOc) values. The data comprise an inductive part in the frequency regi...
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The a.c. impedance behaviour of a commercial sealed Li-ion cell is studied in the temperature range -10 to 40 degreesc at various state-of-charge (SOc) values. The data comprise an inductive part in the frequency region of 100 kHz-100 Hz, and two capacitive parts in the frequency region of 100 Hz-10 mHz. The data are analysed using an equivalent circuit and a nonlinear least square fitting procedure, and the impedance parameters are evaluated. The inductance is found to be independent of temperature and SOc of the cell. The resistance corresponding to the high frequency semicircle of the Nyquist impedance plot, which is attributed to the surface film on the electrodes, shows a weak dependence on the SOc of the cell. On the other hand, it exhibits Arrhenius dependence on temperature. A value of 0.4 +/- 0.05 eV is obtained for activation energy of charge-transport in the surface film. The resistance corresponding to the low frequency semicircle is due to the electron-transfer reactions, and exhibits a strong dependence on the SOc and also temperature. The data are analysed using the Butler-Volmer kinetic equation for activation controlled charge-transfer reaction, and the kinetic parameters, namely, the apparent exchange current, transfer coefficient and activation energy of the cell reaction are evaluated.
carbon fiber-reinforced silicon carbide composites (c/Sic) are widely used in lightweight aerospace structures for thermal protection due to its excellent mechanical properties. The low interfacial shear strength of t...
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carbon fiber-reinforced silicon carbide composites (c/Sic) are widely used in lightweight aerospace structures for thermal protection due to its excellent mechanical properties. The low interfacial shear strength of the composites decreases its performance and limits its application. To investigate the shearing performance of c/Siccomposite, interlaminar shear and in-plane shear tests were conducted. Real-time X-ray micro-computed tomography (XcT) non-destructive testing technology is an effective method for damage analysis of composite materials. The damage mechanisms of 2D plain weave c/Siccomposites prepared by chemical vapor infiltration process under interlaminar shear loading are investigated using the combination of XcT and acoustic emission detection system. The in-situ XcT results reveal the damage visualization mechanisms of the composites and the damage evolution process including matrix damage, interfacial debonding and fiber fracture. The failure mechanisms and morphology of the shear effect for 2D plain weave c/Sic were analysed.
This high-level toolbox for the calculus with Taylor polynomials is named after L.F.A. Arbogast (1759-1803), a French mathematician from Strasbourg (Alsace), for his pioneering work in derivation calculus. Arbogast is...
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This high-level toolbox for the calculus with Taylor polynomials is named after L.F.A. Arbogast (1759-1803), a French mathematician from Strasbourg (Alsace), for his pioneering work in derivation calculus. Arbogast is based on a well-defined extension of the c programming language, Modular c, and places itself between tools that proceed by operator overloading on one side and by rewriting, on the other. The approach is best described as contextualization of ccode because it permits the programmer to place his code in different contexts-usual math or automatic differentiation (AD)-to reinterpret it as a usual c function or as a differential operator. Because of the type generic features of modern c, all specializations can be delegated to the compiler. The higher order AD with arbogast is exemplified on families of functions of mathematical physics and on models for complex dielectric functions used in optics.
An environment-friendly oxidation-reduction method was used to prepare Pd/c hybrid nanocomposites (Ncs) using carbon as host and Pd nanoparticles (NPs) as surface loading, and sodium citrate was used as a reducing age...
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An environment-friendly oxidation-reduction method was used to prepare Pd/c hybrid nanocomposites (Ncs) using carbon as host and Pd nanoparticles (NPs) as surface loading, and sodium citrate was used as a reducing agent. The structures and morphologies of the Pd/c hybrid Ncs were characterized by X-ray diffraction, transmission (high-resolution) electron microscopy (TEM, HRTEM), X-ray photoelectron spectroscopy and so on. The results demonstrated that the Pd NPs were deposited on the surface of the c sphere beads, and the Pd NPs were homogeneous and monodispersed. The results also indicated that the diameter of the Pd NPs was 3 +/- 0.5 nm and the Pd/c Ncs were 197 +/- 6.5 nm. In addition, the Pd/c Ncs showed improved electrocatalytic activity for formic acid oxidation in comparison with commercial Pd NPs through controlling the surface structures. So, the environment-friendly preparation method provided developmental direction to fabricate all kinds of metal/c hybrid Ncs architectures.
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