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Abstract: An analytically nonlocal Euler–Bernoulli beam model for the wave propagation in fluid-filled single-walled carbon nanotube (SWCNT) is established. The governing equations with the nonlocal effects are derived on the variational principle, and used in the wave propagation analysis of the SWCNT beam. Compared with the partially nonlocal Euler–Bernoulli beam models used previously, the analytically nonlocal model presented in the present study predicts well the effects of the stiffness enhancement and the wave damping at the high wavenumber or the strong nonlocal effects area for the fluid-filled SWCNT beam. Though the analytical model is less sensitive than the partially nonlocal model when the moving velocity of the internal fluid is high enough, it simulates more of the high-order nonlocal effecting information than the partially nonlocal model does in many cases. [Copyright &y& Elsevier]

Abstract: This paper is concerned with the characteristics of wave propagation in double-walled carbon nanotubes (DWCNTs). The DWCNTs is simulated with a Timoshenko beam model based on the nonlocal continuum elasticity theory, referred to as an analytically nonlocal Timoshenko-beam (ANT) model. The governing equations of the DWCNTs beam consist of a set of four equations that are derived from the variational principle of the beam with high-order boundary conditions at the both ends, in which the effects of the nano-scale nonlocality and the van der Waals interaction between inner and outer tubes are inclusive. The characteristics of the wave propagation in the DWCNTs beam were analyzed with the new ANT model proposed and the comparisons with the partially nonlocal Timoshenko-beam (PNT) models in publication were made in details. The results show that the nonlocal effects of the ANT model proposed in the present study on the wave propagations are more significant because it is in stronger stiffness enhancement to the DWCNTs beam. [Copyright &y& Elsevier]

• A wireless grinding force measurement module for wafer grinding machine is developed. • The variations of grinding force during the whole grinding process are revealed real-timely. • Effect of process parameter on grinding force, and parameter optimization are investigated. Grinding force is a crucial factor that affects the machining accuracy, wheel wear and the material removal efficiency for precision machining of semiconductor materials under nanometer accuracy. However, due to the complex rotational motion of both the grinding wheel and wafer workpiece, in situ measurement of the grinding force in wafer self-rotating grinding is still a big challenge. In this paper, a novel grinding force measurement method in silicon wafer grinding process is developed. The method is achieved by embedding four thin film force sensors into a self-designed force measurement device and real-time monitoring through wireless signal transmission. Based on this method, the grinding force under 5 groups of process parameters are measured. For the first time, the variations of grinding force during the whole grinding process are revealed real-timely. Effects of process parameters, i.e. spindle rotational speed and feed rate, on grinding force are investigated, and the parameters are also optimized based on the theory of specific grinding energy. The test results show that the force measurement method has the advantages of high precision, reliable and convenient implementation. [ABSTRACT FROM AUTHOR]

Abstract: The Hangzhou Bay faces frequent threats from typhoon-induced storm surge and has attracted considerable attentions of coastal researchers and environmental workers. A three-dimensional storm surge model system based on Finite-Volume Coastal Ocean Model (FVCOM) and analytical cyclone model is applied to investigate the hydrodynamic response in the Hangzhou Bay to tropical typhoon. This model has been used to reproduce the storm surge generated by Typhoon Agnes (No. 8114) and the simulated wind field and water elevations have been compared with the available field observations. A series of numerical experimental cases have been conducted to study the effects of land reclamation project (shoreline relocation and seabed deformation) and cyclonic parameters (minimal central pressure (MCP), radius to maximal wind (RMW) and translation speed (TS)) on the hydrodynamics in the Hangzhou Bay. The results show that the shoreline relocation and seabed deformation could generate much higher storm surge in the vicinity of reclamation project with the shoreline relocation making main contribution (about 70%) to this increase. It is found that among the cyclonic parameters, RMW is the most important factor affecting the peak surge in the Hangzhou Bay. [Copyright &y& Elsevier]

This paper is concerned with vibration analysis considering fluid–structure interaction (FSI) in liquid-filled pipe system using transfer matrix method (TMM) in frequency domain. The emphasis is placing specially upon the multi-span pipe system with middle rigid constraints. Three major mechanisms of coupling, the friction coupling, the Poisson coupling and the junction coupling, as well as both distributed and concentrated external excitations are considered in this study. A phenomenon associated with the rigid constraints, namely, a junction coupling depending on the Poisson coupling and friction coupling (might be called the conditional junction coupling), is revealed and discussed. Numerical examples indicate that the conditional junction coupling has much larger influence on the frequencies of a liquid-filled pipe system than the Poisson coupling does. It is also shown through the numerical examples that the proposed method is efficient. [Copyright &y& Elsevier]

This study investigated the effects of fermentation with kefir grains on the nutritional composition, flavor, and physical stability of hemp seed, and explored its potential as a probiotic plant-based beverage. After fermentation of a homogenized hemp seed water suspension, the concentrations of organic acids (lactic, acetic, tartaric, butyric, succinic, and malic acids) increased. The content of nutritional components, amino acids, and free fatty acids increased, as well as the number (from 16 to 21) and concentrations of flavor compounds, such as alcohols, acids, and esters. Fermentation also increased the particle size, viscosity, and phase-separation resistance of the final product. Therefore, kefir grains improved the nutritional composition, flavor, and physical stability of the hemp seed beverage, indicating its potential as a functional beverage, and providing a theoretical basis for the development of plant-based fermented beverages. • Kefir grain endow that hemp seed with more organic acid. • Kefir grains improve nutrient component of fatty acid and amino acid in hemp seed. • Kefir grains fermentation gives more flavor to the hemp seed. • Kefir grains fermentation can increase the viscosity and stability of hemp seed. [ABSTRACT FROM AUTHOR]

Abstract: Various aggregates, such as spherical and elongated micelles, tubular and rodlike aggregates, as well as vesicles, are induced by adding sodium 2-naphthalenesulfonate (SNphs) or sodium benzenesulfonate (SBzs) into the aqueous solution of a gemini surfactant C12C2C12(Me) (1,2-ethanediyl-bis-(dodecyldimethylammonium bromide)). The aggregate morphology strongly depends on the added amount of the organic salts. Among the various aggregates, the elongated micelle and the tubular aggregate have larger solubilizing capacities than those with the other morphologies. However, SNphs and SBzs cannot induce similar aggregate transitions for the systems of C12C s C12(Me) (s =6, 8, 12). The possible mechanism of these phenomena is proposed based on the results of UV spectra and 1H NMR measurements and the molecular packing geometry rule. [Copyright &y& Elsevier]