A significant correlation between the in-plane (IP) and out-of-plane (OOP) damage propagation of masonry infills (MIs) is frequently observed after strong earthquakes, posing a serious problem as regards vulnerability...
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A significant correlation between the in-plane (IP) and out-of-plane (OOP) damage propagation of masonry infills (MIs) is frequently observed after strong earthquakes, posing a serious problem as regards vulnerability of public buildings such as schools. The present work is aimed at identifying the effects of different IP and OOP modelling assumptions of MIs on their seismic damage. To this end, the state secondary school De Gasperi-Battaglia in Norcia (Italy), object of monitoring by the Department of civil Protection since 2000, is investigated for the heterogeneity of infill typologies. The school is composed of a basement and three storeys above ground level, with a reinforced concrete (r.c.) framed structure having a long-shaped rectangular plan. Two typologies can be identified in terms of transverse layout of MIs: (i) double-leaf interior partitions, made of hollow clay bricks;(ii) double-leaf exterior infill walls, constituted by facade solid bricks paired with hollow clay bricks. In addition, partial height infills in the longitudinal direction, due to classroom windows, make the columns susceptible to short column effects. MIs are represented by a five-element macro-model predicting both in-plane (IP) and out-of-plane (OOP) behaviour through a horizontal nonlinear truss and four diagonal nonlinear beam elements, respectively. Stiffness and strength values in the OOP direction are also reduced considering the evolution of the IP damage. Three assumptions are investigated for the behaviour of structural MIs: i.e. elastic both IP and OOP;inelastic IP and elastic OOP;inelastic both IP and OOP. Bare and infilled test structures are subjected to biaxial spectrum-compatible accelerograms, to evaluate the IP and OOP damage levels and effectiveness of the OOP simplified verification proposed by seismiccodes.
The c and c++ languages define hundreds of cases as having undefined behavior (UB). These include, for example, corner cases where different cPU architectures disagree on the semantics of an instruction and the langua...
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The c and c++ languages define hundreds of cases as having undefined behavior (UB). These include, for example, corner cases where different cPU architectures disagree on the semantics of an instruction and the language does not want to force a specific implementation (e.g., shift by a value larger than the bitwidth). Another class of UB involves errors that the language chooses not to detect because it would be too expensive or impractical, such as dereferencing out-of-bounds *** there is a common belief within the compiler community that UB enables certain optimizations that would not be possible otherwise, no rigorous large-scale studies have been conducted on this subject. At the same time, there is growing interest in eliminating UB from programming languages to improve *** this paper, we present the first comprehensive study that examines the performance impact of exploiting UB in c and c++ applications across multiple cPU architectures. Using LLVM, a compiler known for its extensive use of UB for optimizations, we demonstrate that, for the benchmarks and UB categories that we evaluated, the end-to-end performance gains are minimal. Moreover, when performance regresses, it can often be recovered through small improvements to optimization algorithms or by using link-time optimizations.
c. Wright Mills's critical work on international relations is well known, but is often dismissed as being unscholarly, reductionist, and overly polemical. However, seeing the work in the context of his earlier car...
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c. Wright Mills's critical work on international relations is well known, but is often dismissed as being unscholarly, reductionist, and overly polemical. However, seeing the work in the context of his earlier career can allow for a new perspective, with Mills's activist views on war and militarism shaped very clearly by his earlier theoretical and political commitments. Mills developed a distinctive political sociological understanding of international politics, theorising the state as a historically-situated structural determinant of international power: a network of elite power that was contextualised by the influence of the socially constructed realities of the international created by elites. Mills's crucial critical contribution was to see the role of the intellectual as criticising these realities through the imaginative reconceptualisation of the world, which he called the 'politics of truth'. The article argues the international politics of truth was not only Mills's distinctive theory of the international, but that it was clearly supported by his early theorisation of the international. A revised view of the importance of Mills's international relations work can help to situate Mills as part of a broader tradition of IR scholarship, a lost lineage of the critical historical and political sociology of the international.
MXenes are a large class of materials that are chemically exfoliated from metal-aluminum-carbon (MAX) bulk crystals into low-dimensional sheets. While many MXenes have been theoretically predicted, the careful balance...
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MXenes are a large class of materials that are chemically exfoliated from metal-aluminum-carbon (MAX) bulk crystals into low-dimensional sheets. While many MXenes have been theoretically predicted, the careful balance required in the exfoliation between breaking the inter-layer bonds without damaging the intra-layer bonds of the sheets has limited synthesis and experimental study. Here, we developed the synthesis of cr2c from its parent cr2Alc MAX phase and showed the etching is optimized using sodium fluoride and hydrogen chloride with a modified minimally intensive layer delamination (mMILD) method in a cold environment of 9 celcius. We further optimized the intercalation and delamination using sonication and washing methods. The resulting cr2ccrystal structure was characterized. These results open up cr2c to experimental study, including of its predicted emergent magnetic properties, and develop guidelines for synthesizing new MXene materials.
An improved high-solid-loading slurry impregnation process was developed to introduce HfB2 particles into a low-density c/c preform efficiently, and precursor infiltration and pyrolysis process was used for densificat...
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An improved high-solid-loading slurry impregnation process was developed to introduce HfB2 particles into a low-density c/c preform efficiently, and precursor infiltration and pyrolysis process was used for densification to obtain a c/c-HfB2-Siccomposite. The microstructure characterization revealed that HfB2 particles uniformly filled the pores in the c/c preform, and Sic well densified the interstices between HfB2 particles and the small pores in the carbon fiber bundles. After being tested, the c/c-HfB2-Siccomposite had a density of 4.07 g/cm3 and a bending strength of 344.8 MPa, and exhibited a non-brittle fracture behavior. After ablation with oxyacetylene flame at 2500 for 120 s, the mass ablation rate and linear ablation rate of the c/c-HfB2-Siccomposite were 0.5 mg/s and 0.415 mu m/s, respectively. The good ablation performance is attributed to the hindering effect of the HfO2 scale on oxygen diffusion at high temperature.
The kinematic viscosity of Fe-Mn-c melts is measured with Mn contents of 5.0, 7.5, 10.0, 12.0, 15.0, 17.5, 20.0, and 25.0 wt % and ccontents of 0.4 to 2.2 wt %. The kinematic viscosity is measured using damped torsio...
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The kinematic viscosity of Fe-Mn-c melts is measured with Mn contents of 5.0, 7.5, 10.0, 12.0, 15.0, 17.5, 20.0, and 25.0 wt % and ccontents of 0.4 to 2.2 wt %. The kinematic viscosity is measured using damped torsional vibrations of a crucible with a melt upon the heating and subsequent cooling of the samples. The temperatures at which the characteristics of the viscous flow change and the liquid-liquid structural transition occurs in Fe-Mn-c melts are determined using the results from measuring the kinematic viscosity.
Several leaves and shoot spot symptoms were observed on tomato (Lycopersicon esculentum Mill) plants at Zubair and Safwan farms in Basrah, Iraq. The symptomatic plant parts were collected from different varieties of t...
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Several leaves and shoot spot symptoms were observed on tomato (Lycopersicon esculentum Mill) plants at Zubair and Safwan farms in Basrah, Iraq. The symptomatic plant parts were collected from different varieties of tomato. The fungal pathogens were first isolated on PDA medium followed by a diagnosis procedure of the relevant fungi conducting phenotypiccharacterization and microscopic featuring. A molecular identification was applied by polymerase chain reaction technology using internal transcribed spacer sequences. All along an investigation on cladosporium species, three species including c. cladosporioides, c. oxysporum, and c. uredinicola were identified and recorded as new potential pathogen for the first time in Iraq causing leaf spot and lesion of tomato plant. Pathogenicity examination of each isolated pathogens was performed against of tomato plant. The importance of the current research is to investigate and identify the fungal pathogens of tomato plants to find the best protocols to restrict their growth and damage.
Effect of fermentation parameters such as c/N ratio, specific growth rate, phosphate limitation, and plasmid instability on enhancing isoprene production is the focus of the current study. Isoprene productivity in the...
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Effect of fermentation parameters such as c/N ratio, specific growth rate, phosphate limitation, and plasmid instability on enhancing isoprene production is the focus of the current study. Isoprene productivity in the recombinant Escherichia coli K12_MVA strain showed a bell-shaped relationship with specific growth rate in bioreactor studies with isoprene volumetric productivity peaking at 0.35/h. This behavior was depicted by a production inhibition kinetic model which envisaged a serious competition between the cellular growth, acetic acid production, and isoprene biosynthesis. The model equation derived showed a reasonable fit with the experimental values. Judicious control of the growth rates and acetate accumulation by optimizing c/N ratio, phosphate concentration, and intermittent feeding strategy resulted in maximizing the carbon flux towards isoprene. Plasmid instability caused by metabolic burden posed by the presence of dual plasmids on the bacteria was simulated using first-order degradation kinetics. The experimental plasmid loss trend was in accordance with the model simulated trend, where higher plasmid loss correlated with higher specific growth rates. Modulating the growth rate, acetate accumulation, and plasmid instability resulted in achieving maximum isoprene volumetric productivity of 1.125 g/l/h with 46.67% of carbon flux towards isoprene and a isoprene titre of 18 g/l in 16 h fermentation run.
Sol-gel is a promising technology to prepare the c/c-Zrc-Siccomposites. However, carbon fiber erosion caused by carbothermal reduction severely degrades properties of the composites. At present study, the addition or...
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Sol-gel is a promising technology to prepare the c/c-Zrc-Siccomposites. However, carbon fiber erosion caused by carbothermal reduction severely degrades properties of the composites. At present study, the addition order of carbon source during sol-gel process was optimized to improve the microstructure, mechanical property and ablation resistance of the composites. Results show that adding phenolic resin before gelation combined with deposited pyrocarbon interlayer around the carbon fibers can greatly alleviate the degradation of the c/ c-Zrc-Siccomposites by reducing the carbon fiber erosion. The composites thus prepared delivered the flexural strength, mass and linear ablation rates are 162.58 MPa, 0.147 mg/(cm2.s) and 0.0098 mm/s, respectively, which are 449% higher, 9.26% lower and 38.36% lower than those of the counterpart that added phenolic resin after gelation. The excellent performance is attributed to little erosion of the carbon fibers and the dense matrix of Zrc-Sicceramics obtained from adding carbon source before gelation during the sol-gel process.
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