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Steel fiber reinforced concrete (SFRC) is widely applied in the construction industry. Numerical elastoplastic analysis of the macroscopic behavior is complex. This typically involves a piecewise linear failure curve including corner singularities. This paper presents a single smooth biaxial failure curve for SFRC based on a semianalytical approximation. Convexity of the proposed model is guaranteed so that numerical problems are avoided. The model has sufficient flexibility to closely match experimental results. The failure curve is also suitable for modeling plain concrete under biaxial loading. Since this model is capable of simulating the failure states in all stress regimes with a single envelope, the elastoplastic formulation is very concise and simple. The finite element implementation is developed to demonstrate the conciseness and the effectiveness of the model. The computed results display good agreement with published experimental data. CE Database subject headings: Fiber reinforced materials; Concrete; Steel; Failure modes; Elastoplasticity; Construction materials.

In this study, two new coordination polymers (CPs),{[(CH3)2NH2][Zn(FDA)(TZ)2]}n (1, H2FDA = furan-2,5-dicarboxyl acid, TZ = 1,2,3-triazole) and {[Ni2(H2O)3(HTTCA)]·H2O}n (2, H4TTCA = [1,1':2',1''-terphenyl]-3,3'',4',5'-tetracarboxylic acid), have been prepared under solvothermal conditions and characterized by single-crystal X-ray diffraction analyses successfully. Furthermore, the protective effect of the compounds in vitro and in vivo was evaluated. Firstly, the bacterial growth curves were measured after treatment with the compounds. Besides, the inflammatory cytokines in the blood was detected with enzyme linked immunosorbent assay (ELISA) detection kit. Two new coordination polymers (CPs) have been prepared under solvothermal conditions and characterized by single-crystal X-ray diffraction analyses successfully. Furthermore, the protective effect of the compounds in vitro and in vivo was evaluated. Firstly, the bacterial growth curves were measured after treatment with the compounds. Besides, the inflammatory cytokines in the blood was detected with enzyme linked immunosorbent assay (ELISA) detection kit. [ABSTRACT FROM AUTHOR]

Two-dimensional (2D) transition metal dichalcogenides (TMDCs) such as tungsten diselenide (WSe2) have spead many interesting physical properties, which may become ideal candidates to develop new generation electronic and optoelectronic devices. In order to reveal essential features of 2D TMDCs, it is necessary to fabricate high-quality devices with reliable electrical contact. We systematically analyze the effect of graphene and metal contacts on performance of multi-layered WSe2 field effect transistors (FETs). The temperature-dependent transport characteristics of both devices are tested. Only graphene-contacted WSe2 FETs are observed with the metal-insulator transition phenomenon which mainly attributes to the ultra-clean contact interface and lowered contact barrier. Further characterization on contact barrier demonstrates that graphene contact enables lower contact barrier with WSe2 than metal contact, since the Fermi level of graphene can be modulated by the gate bias to match the Fermi level of the channel material. We also analyze the carrier mobility of both devices under different temperatures, revealing that graphene contact can reduce the charge scattering of the device caused by ionized impurities and phonon vibrations in low and room temperature regions, respectively. This work is expected to provide reference for fabricating 2D material devices with decent performances. [ABSTRACT FROM AUTHOR]