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A compression moulded Kevlar-phenolic resin composite consisting of 30 wt% continuous fibres was slid against a steel disc such that the fibre axis was normal to the sliding plane. The sliding experiments were conducted in a normal pressure range of 0.47–4.27 MPa and at a sliding speed of 0.5 ms–1. The initial sliding interaction is abrasive. With further sliding, as patches of polymer transfer film develop on the polymer pin and counterface, the interaction becomes adhesive and steady-state friction is established. The wear resistance of the polymer was found to be related to the stability of this film.  相似文献   
23.
Model-Based Diagnosis of Hybrid Systems   总被引:3,自引:0,他引:3  
Techniques for diagnosing faults in hybrid systems that combine digital (discrete) supervisory controllers with analog (continuous) plants need to be different from those used for discrete or continuous systems. This paper presents a methodology for online tracking and diagnosis of hybrid systems. We demonstrate the effectiveness of the approach with experiments conducted on the fuel-transfer system of fighter aircraft  相似文献   
24.
Calmodulin (CaM) has been reported to have affinity for the estrogen receptor (ER). Observations reported here reveal a direct physical interaction between purified CaM and ER. This direct ER-CaM interaction may be an initial event preceding the assembly of ER plus auxiliary proteins into the active ER complex with its DNA motif, the estrogen response element. We demonstrate that CaM is an integral component of this complex by using a system reconstituted from purified ER and nuclear extract from ER-negative breast cancer cells and also with ER-depleted nuclear extract of an ER-positive breast cancer cell line. Although CaM is essential for formation of this complex, it is not sufficient, suggesting roles also of auxiliary proteins. CaM also is functionally required for activation of an ER-responsive promoter, in the 17beta-estradiol-ER pathway of hormone action and regulation of 17beta-estradiol-responsive gene expression that is associated with proliferation of mammary epithelial cells.  相似文献   
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Water Resources Management - Reference evapotranspiration (ET0) is a crucial element for deriving irrigation scheduling of major crops. Thus, precise projection of ET0 is essential for better...  相似文献   
27.
It is shown that if the root-mean-square of the gradient of the phase fluctuation of either of the components exceeds the corresponding inverse of the coherence length or if the chemical potential exceeds 1 0 or 2 0 , where is the volume integrals of the interaction function between the components, and 1 0 , 2 0 are the densities of the two components, the mixture of two rotating superfluids has an instability.  相似文献   
28.
The Journal of Supercomputing - In this article, the authors suggested a rotation-invariant local binary pattern-based weighted generalized closest neighbor (RILBP-WGCN) method for HSI...  相似文献   
29.
Microsystem Technologies - Single-Walled Carbon Nanotubes (SWCNTs) are widely used as potential carriers in drug delivery systems. The objective of this work was to observe the effects of pristine,...  相似文献   
30.
A mathematical model for the transient heat flow analysis in arc-welding processes is proposed, based on a unique set of boundary conditions. The model attempts to make use of the relative advantages of analytical as well as numerical techniques in order to reduce the problem size for providing a quicker solution without sacrificing the accuracy of prediction. The variation of thermo-physical properties with temperature has been incorporated into the model to improve the thermal analysis in the weld and heat-affected zones. The model has been evaluated using a five-point explicit finite difference method for analysing the welding heat flow in thin plates of two different geometric configurations. The temperature distribution closer to the heat source, primarily in the weld zone and the heat-affected zones, are predicted by the numerical technique. The thermal characteristics beyond the heat-affected zone are amenable to standard analytical techniques. The behaviour of the boundary condition in the model has been investigated in detail.Nomenclature q Rate of heat per unit thickness (Wm–1) - d Plate thickness (m) - v Velocity of source (m s–1) - t Time (s) - T Temperature value at the desired point (K) - T 0 Initial temperature (K) - K Thermal conductivity (W m–1 K–1) - Density (kg m–3) - c p Specific heat (J kg–1 K–1) - Thermal diffusivity (m2 s–1) - n - Distance of point considered from the source (=x–vt) (m) - K 0 Modified Bessel function of second kind and zero order - r Radial distance from the source (r=(x 2+y 2)1/2) (m) - Model width (m) - a Plate width (m) - Distance from the source =(2+4 ×10–4)1/2 (m) - n   相似文献   
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