The enhancement of TiO?photocatalytic activity by hydrogen thermal treatment

Author name used in this publication: H. LiuAuthor name used in this publication: X. Z. Li2002-2003 > Academic research: refereed > Publication in refereed journalAccepted ManuscriptPublishe

Dynamic responses of metal sandwich beams under high velocity impact considering time inhomogeneity of core deformation

The objective of this paper is to establish a yielding criterion for a sandwich beam by considering the time inhomogeneity of foam core deformation, which results in the time-varied neutral surface and cross-sectional area. Taking into account of the bending and axial stretching, a unified dynamic yielding criterion for metallic sandwich beams considering the mass redistribution along with the core compression is established. A membrane factor is proposed and an analytical solution for the large deflection of the beam under high velocity impact is given. Different from the traditional yielding surface, when the core is partially densified, the yielding surface is asymmetric. Comparison of analytical solutions with numerical ones reveals that the present model improves the prediction accuracy of high-velocity impact responses of fully clamped sandwich beams. The present method can also be degenerated to predict the low velocity/energy impact responses of sandwich beams.The financial supports from the Fundamental Research Funds for the Central University (Nos. 2014JBZ014 and 2014YJS109), the National Science Foundation of China (No. 11272046), and 973 Program (No. 2015CB057800) are acknowledged

基于局部模糊方差的过渡区提取及图像分割

Author name used in this publication: 田岩Author name used in this publication: 刘继军Author name used in this publication: 谢玉波Author name used in this publication: SHI Wen-Zhong2007-2008 > Academic research: refereed > Publication in refereed journal202012 bcrcVersion of RecordPublishe

Flight of the dragonflies and damselflies

This work is a synthesis of our current understanding of the mechanics, aerodynamics and visually mediated control of dragonfly and damselfly flight, with the addition of new experimental and computational data in several key areas. These are: the diversity of dragonfly wing morphologies, the aerodynamics of gliding flight, force generation in flapping flight, aerodynamic efficiency, comparative flight performance and pursuit strategies during predatory and territorial flights. New data are set in context by brief reviews covering anatomy at several scales, insect aerodynamics, neuromechanics and behaviour. We achieve a new perspective by means of a diverse range of techniques, including laser-line mapping of wing topographies, computational fluid dynamics simulations of finely detailed wing geometries, quantitative imaging using particle image velocimetry of on-wing and wake flow patterns, classical aerodynamic theory, photography in the field, infrared motion capture and multi-camera optical tracking of free flight trajectories in laboratory environments. Our comprehensive approach enables a novel synthesis of datasets and subfields that integrates many aspects of flight from the neurobiology of the compound eye, through the aeromechanical interface with the surrounding fluid, to flight performance under cruising and higher-energy behavioural modes

Extremal solutions for p-Laplacian fractional integro-differential equation with integral conditions on infinite intervals via iterative computation

We study the extremal solutions of a class of fractional integro-differential equation with integral conditions on infinite intervals involving the p-Laplacian operator. By means of the monotone iterative technique and combining with suitable conditions, the existence of the maximal and minimal solutions to the fractional differential equation is obtained. In addition, we establish iterative schemes for approximating the solutions, which start from the known simple linear functions. Finally, an example is given to confirm our main results

Detection of mild to moderate influenza A/H7N9 infection by China's national sentinel surveillance system for influenza-like illness: case series

published_or_final_versio

Sustained hyperosmolarity increses TGF-beta1 and Egr-1 expression in the rat renal medulla.

BACKGROUND: Although TGF-ss and the transcription factor Egr-1 play an important role in both kidney fibrosis and in response to acute changes of renal medullary osmolarity, their role under sustained hypo- or hyperosmolar conditions has not been elucidated. We investigated the effects of chronic hypertonicity and hypotonicity on the renal medullary TGF-ss and Egr-1 expression. METHODS: Male adult Sprague Dawley rats (n = 6/group) were treated with 15 mg/day furosemide, or the rats were water restricted to 15 ml/200 g body weight per day. Control rats had free access to water and rodent chow. Kidneys were harvested after 5 days of treament. In cultured inner medullary collecting duct (IMCD) cells, osmolarity was increased from 330 mOsm to 900 mOsm over 6 days. Analyses were performed at 330, 600 and 900 mOsm. RESULTS: Urine osmolarity has not changed due to furosemide treatment but increased 2-fold after water restriction (p < 0.05). Gene expression of TGF-ss and Egr-1 increased by 1.9-fold and 7-fold in the hypertonic medulla, respectively (p < 0.05), accompanied by 6-fold and 2-fold increased c-Fos and TIMP-1 expression, respectively (p < 0.05) and positive immunostaining for TGF-ss and Egr-1 (p < 0.05). Similarly, hyperosmolarity led to overexpression of TGF-ss and Egr-1 mRNA in IMCD cells (2.5-fold and 3.5-fold increase from 330 to 900 mOsm, respectively (p < 0.05)) accompanied by significant c-Fos and c-Jun overexpressions (p < 0.01), and increased Col3a1 and Col4a1 mRNA expression. CONCLUSION: We conclude that both TGF-ss and Egr-1 are upregulated by sustained hyperosmolarity in the rat renal medulla, and it favors the expression of extracellular matrix components