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Purpose: Considering the transportation structure in the factory is responsible for transporting materials, thus when analysing the axially moving characteristics of the conveyor belt in operation, the effect of the load must be considered. Methods: Based on Von Karman’s nonlinear plate theory, the motion equations of the system are established using the assumed mode method and Hamilton’s principle. The effects of the concentrated mass positions on the dynamic characteristics of the system are analyzed. The stability properties of the system are analyzed by solving the generalized eigenvalue problem. The amplitude–frequency response curves of the transverse generalized displacements of the system are drawn and analyzed by numerical calculation. Results: The effects of the concentrated mass position, the axially moving velocity, and the external excitation amplitude on the nonlinear amplitude–frequency responses of the system are studied. The results show that the concentrated mass position has significant effects on the natural frequency of the system. All the amplitude–frequency response curves of the system under the harmonic excitation show the hardening type nonlinearity. The concentrated mass and the axially moving velocity have a great influence on the first- and second-order resonances of the system. With the excitation amplitude, axially moving velocity, and concentrated mass changing, the system appears complex nonlinear response phenomena.

In this paper, the dynamic response of axially moving geometric nonlinear plates carrying moving mass is investigated. Based on von Kármán plate theory, the time-varying dynamic equation of the axially moving plate under moving loads is obtained by using the extended Hamiltonian principle and discretized into a set of finite-dimensional ordinary differential nonlinear equations by the assumed mode method. The equation incorporates the additional mass, damping, and stiffness matrix resulting from the inertia force, centrifugal force, and Coriolis force of the moving mass. Comparing the axially moving of plate, dynamic response results of linear and nonlinear results show the necessity of considering geometric nonlinearity in the model. The effects of system load parameters, including the mass of the moving load, the speed of the axially moving plate, and the plate’s aspect ratio on the vibration characteristics of the plate, are discussed. The dynamic responses of the axially moving plates under three different moving load trajectories are contrasted. Numerical results show that increasing the moving load mass and the speed of the axially moving plate leads to greater instability of the system, and the aspect ratio and different moving trajectories also have effects on the transverse vibration of the plate.

In this research, a series of Sm3+doped CsLu(WO4)2phosphors was prepared via high temperature solid phase technique to design new red phosphors and optical thermometric materials. Their structures, morphology, band gap and luminescence properties were characterized by X-ray diffraction, scanning electron microscopy, diffuse reflection and luminescence spectra, respectively. Under UV excitation, CsLu(WO4)2gives rise to a blue broad emission band between 350 and 700 nm, which stems from the 3T1u→ 1A1gtransition of WO66−groups. When Sm3+is introduced into CsLu(WO4)2, energy transfer between WO66−groups and Sm3+ions takes place in CsLu(WO4)2:Sm3+phosphors, and color-tunable luminescence from blue to red is realized by controlling the Sm3+doping concentration. The energy transfer efficiency between WO66−groups and Sm3+ions was analyzed, and the energy transfer mechanism was determined to be dipole–dipole interactions. According to the temperature-dependent luminescence spectra, WO66−groups and Sm3+ions exhibit large discrepancy in thermal quenching rates, and thus the temperature sensing properties of CsLu(WO4)2:Sm3+in the temperature range of 283–403 K were analyzed. Based on the framework of fluorescence intensity ratio theory, the basic optical thermometry parameters including absolute and relative sensitivity of CsLu(WO4)2:Sm3+were calculated and the results show that it has great potential for application in optical thermometry.

A large Ho3+:Li3Ba2La3(MoO4)8crystal with high optical quality and well-developed appearance was grown by the flux method. The main spectral properties of the crystal, including the absorption spectra, fluorescence spectra and fluorescence decay curves were recorded at room temperature. The Judd-Ofelt (J-O) theory was applied to calculate the oscillator strength parameters Ωt(t=2, 4, 6), spontaneous emission probabilities, fluorescence branching ratios, and radiative lifetimes of Ho3+ions undergoing transitions from ground state 5I8to the excited states. The stimulated emission cross-section for the 5I7→5I8transition was estimated to be 1.32×10−20cm2at 2045 nm by Fuchtbauer-Ladenburg (F-L) equation and the quantum efficiency of the 5I7level was calculated to be 89%.

To separate CO2from coal-fired power plant emissions, semicoke, which is cheap and easy to obtain, was further activated to use as the carrier and tetraethylenepentamine (TEPA) was impregnated in the activated semicoke to prepare solid amine sorbents. The effects of activating agents, adsorption temperature, and the presence of water on CO2sorption were investigated in a fixed-bed reactor, and the regenerability and adsorption kinetics for prepared sorbents were also studied. The equilibrium adsorption capacity for N2-activated semicoke (SE-N2) was 2.70 and 2.14 mmol/g at 20 °C when water was absent and present, respectively, and the equilibrium adsorption capacity for 10 wt % TEPA-modified N2-activated semicoke (SE-N2-TEPA10%) was 3.24 and 3.58 mmol/g at 60 °C when water was absent and present, respectively. After 10 cyclic regenerations, the adsorption capacity for SE-N2-TEPA10% reduced by 7.7% under dry conditions, and SE-N2-TEPA10% showed good regenerability.

Image-enhanced endoscopy refers to techniques of enhancing mucosa surface contrast with the ultimate aim of improving lesion detection and diagnosis. It is vital to detect early gastric cancer as it may be possible to perform curative endoscopic resection. In this topic review, we summarize the options available, such as the traditional dye-based chromoendoscopy, as well as the newer equipment-based techniques such as narrow-band imaging, flexible spectral imaging color enhancement, and i-scan. We further discuss in greater detail the technique of narrow-band imaging combined with magnifying endoscopy, and how this has facilitated lesion characterization and diagnosis based on characteristic abnormal microvascular and microsurface features. Other endoscopic imaging modalities such as autofluorescence imaging and endoscopic microscopy are also briefly discussed.

Microarrays serve scientists as a powerful and efficient tool to observe thousands of genes and analyse their activeness in normal or cancerous tissues. In general, microarrays are used to measure the expression levels of thounsands of genes in a cell mixture. Gene expression data obtained from microarrays can be used for various applications. One such application is that of gene selection. Gene selection is very similar to the feature selection problem addressed in the machine-learning area. In a nutshell, gene selection is the problem of identifying a minimum set of genes that are responsible for certain events (for example the presence of cancer). Informative gene selection is an important problem arising in the analysis of microarray data. In this paper, we present a novel algorithm for gene selection that combines Support Vector Machines (SVMs) with gene correlations. Experiments show that the new algorithm, called GCI-SVM, obtains a higher classification accuracy using a smaller number of selected genes than the well-known algorithms in the literature.