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61.
In this paper, we study the nonlocal nonlinear evolution equation
CD0|tαu(t,x)?(J1|u|?|u|)(t,x)+CD0|tβu(t,x)=|u(t,x)|p,t>0,xRd,
where 1<α<2, 0<β<1, p>1, J:RdR+, 1 is the convolution product in Rd, and CD0|tq, q{α,β}, is the Caputo left-sided fractional derivative of order q with respect to the time t. We prove that the problem admits no global weak solution other than the trivial one with suitable initial data when 1<p<1+2βdβ+2(1?β). Next, we deal with the system
CD0|tαu(t,x)?(J1|u|?|u|)(t,x)+CD0|tβu(t,x)=|v(t,x)|p,t>0,xRd,CD0|tαv(t,x)?(J1|v|?|v|)(t,x)+CD0|tβv(t,x)=|u(t,x)|q,t>0,xRd,
where 1<α<2, 0<β<1, p>1, and q>1. We prove that the system admitsnon global weak solution other than the trivial one with suitable initial data when 1<pq<1+2βdβ+2(1?β)max{p+1,q+1}. Our approach is based on the test function method.  相似文献   
62.
The purpose of this work is the synthesis of two series of layered silicate materials with different ratios (10, 30, 50, 80 and 100) of Cu(NO3)2, or Zn(NO3)2 by ion-exchange method. Several analysis techniques have been used such as X-ray diffraction, energy dispersive X-ray spectroscopy, thermogravimetric analysis, scanning electron microscope and Fourier transform infrared spectroscopy. The results revealed that ion-exchange method of copper and zinc with different ratios did not affect the structure of Na-magadiite. The gap between the theoretical and experimental ion-exchange are in agreement. Antibacterial activity test against Escherichia coli, Rhizobium sp. and Staphylococcus demonstrate that when ratio was (30, 50, 80 and 100) the antibacterial activity of the layered silicate materials showed high antibacterial activity.  相似文献   
63.
Neural Computing and Applications - This research intends to use machine learning approaches to predict tunnel geology and its construction time and costs. For this purpose, the Gaussian Process...  相似文献   
64.
In process planning, determining feature’s machining precedence is an essential step. The task becomes more difficult if features interact with each other, in which case the feature precedence information may suggest multiple machining sequences of the features. This paper considers interacting features in a feature-based model for process planning tasks. For each feature, precedence information is generated considering both roughing and finishing operations. A rule-based system is developed and implemented based on the information about machining precedence of the interacting features. The STEP-NC data model is used as the underlying data model. This model is object-oriented and compliant with the existing STEP standards. The output of the system is also in the STEP format through an information model developed using the EXPRESS language.  相似文献   
65.
Experimental assessment of hydrostatic thrust bearing performance   总被引:1,自引:0,他引:1  
This work presents an experimental study to assess the performance characteristics of hydrostatic thrust bearings. A test rig is designed for testing two configurations of hydrostatic bearings compensated by a capillary tube, one with a mid-circular recess and the other with multi-sectors (four recesses of different recess radii ratios). The performance characteristics have been measured, namely, oil film thickness, recess pressure, pressure distribution and oil flow rate. A specially devised computer program using an iterative technique has been adopted to compute numerically the pressure distribution and predict other performance characteristics. Good agreement has been obtained between predicted theoretical performance and that experimentally measured. The results demonstrate that the bearing recess size and location have a great influence on the performance of the hydrostatic thrust bearing.  相似文献   
66.
The frictional behaviour was experimentally investigated of alumino-silicate ceramics (3Al2O3, 2SiO2) rubbing against a hard steel surface under static and kinetic friction conditions. Tests were carried out on a pin-on-disc machine under both dry and wet contact conditions. Results showed that the frictional behaviour under either static or kinetic conditions was highly dependent on the ceramic body phase transformation which in turn was controlled by the firing temperature during ceramic processing and treatment. Lower friction values were evident when using specimens of ceramic bodies containing a high mullite crystalline phase, which are attained at high firing temperatures. Both the running speed and applied loads had insignificant effects at high loads.During kinetic friction tests lower frictional values were displayed than for static friction tests under wet contact conditions, and under dry conditions when using high mullite ceramic bodies. For specimens of ceramics fired at relatively low temperatures, kinetic friction tests produced higher frictional values than static friction tests.  相似文献   
67.
The surface and self-aggregation properties in water of a new series of amphiphilic homologues, bis-benzimidazolone derivatives of d-glucose, were investigated. Parameters such as the maximal surface excess concentration, minimal area per molecule at the interface, and critical micelle concentration (CMC) were found to be significantly dependent on the hydrophobic alkyl chain length. The synthesized compounds form micelles at remarkably low concentrations, and CMCs derived from surface tension measurements show a minimum as a function of the alkyl chain length; this unusual trend can be attributed to the formation of submicellar aggregates in compounds with long alkyl chains, as evidenced from fluorescence probe spectroscopy data. At high surfactant concentrations, lyotropic liquid crystalline phases with hexagonal structure are formed. Small angle X-ray scattering measurements indicate that the characteristic nanoscopic lengths increase with water swelling and alkyl chain length.  相似文献   
68.
The selection of critical control points is one of the most important steps in the design of a hazard analysis and critical control points system. In this study, the influence of starter culture inoculation on biogenic amine accumulation in fresh fermented sausage as critical control point was studied. The effect of three starter culture Lactobacillus plantarum plus Bifidobacterium lactis, L. plantarum plus Bifidobacterium bifidum or L. plantarum plus B. lactis and B. bifidum on amines production were investigated. Tyramine (TY), Cadaverine (CA), Putrescine (PU), Histamine (HIS) and Tryptamine (TR) contents increased during the fermentation and storage stage, and TY was the prevailing amine in the final product. Sausages produced by fermentation with starters, as compared to natural fermentation (control), had a lower amount of biogenic amine. A great reduction in biogenic amine content was achieved when Bifidobacterium sp. were inoculated, also levels of species of Enterobacteriaceae and Pseudomonas decreased, while lactic acid bacteria counts increased during fermentation and storage.  相似文献   
69.
Detection of porcine plasma using indirect ELISA was developed using mAb B4E1 for the prevention of their usage in human food that creates religious and health conflicts. The immunoassay has a CV < 20% and did not cross-react to other meat and non-meat proteins. The sensitivity of the assay is 0.25% (w/w) of porcine plasma in spiked raw and cooked fish surimi. The assay did not produce a false positive result for any of the commercial fish surimi tested that were not contain porcine plasma. Determination of a 60-kDa antigenic protein of porcine blood using Western blot confirmed its presence in the plasma fraction of the porcine blood. Further proteomic analysis involving liquid chromatography–tandem mass spectrometry (LC-MS/MS) revealed the 60-kDa protein to be porcine serum albumin.  相似文献   
70.
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