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The accurate measurement of individual species of cosmic rays (CRs) is very important to solve the problem of their origin. CR spectra with energies > 100 TeV can be evaluated only by detecting extensive air showers on the ground. Thus, identifying the primary components of CRs depends highly on hadronic interaction models. Direct Cherenkov light (DC-light) emitted by the primary components of CRs prior to first interaction in the atmosphere can be used to identify such primary components. The intensity of DC-light is proportional to the square of the charge of CRs primary components and independent of the hadronic interaction model. In this study, we investigate the characteristics of DC-light and its ability to discriminate heavy nuclei (iron and MgAlSi) from CR components by using the Wide Field-of-view Cherenkov Telescope Array of the Large High-Altitude Air-Shower Observatory (LHAASO-WFCTA) in the energy range between 50 TeV and 500 TeV. Results suggest that DC-light can be used in the LHAASO to improve the reconstruction accuracy of CR heavy components.

For the reasearch of magnetic memory testing parameters on the effect of magnetic memory testing signals, the method of uniform design experiment is used to arrange test, by the decision criteria of the minimum component change of magnetic field, the mathematical model is established based on the test result, quantify the influence of the magnetic memory testing parameters, and optimal regression equations are verified through the test results, and achieve the optimization of test parameters, the results for the determination of magnetic memory testing parameters and the range of choice to provide theoretical reference, and improve the reproducibility of test results.

As a new emerging kind of flooring, antique style flooring has been warmly welcomed by the market. The production of the flooring is produced through artificial processing only and result in some problems. In this paper, a new patented CNC grinding system is introduced, which makes it possible to process concave-convex surface on flooring automatically. There were two major points in developing the system. Firstly, the concave-convex surface processed by this system must have the same visual effects as those processed in artificial way, denting and protruding randomly and maintaining the natural beauty of wood. Secondly, efficiency was another key point for this system. Research goal was to realize the continuous processing, so that more products could be obtained in a shorter time. Test results show that the system could achieve the original design purpose thus providing with a new technology for concave-convex surface processing of antique style flooring.

An organic compound containing N, B and O was synthesised by reacting 3-hydroxymethyl-quinazolin-4-ones and formalin in 1, 4-dioxane solution, the resulting product then being reacted with butanol and boric acid in dimethylbenzene solution. The tribological performance of the novel compound when added to liquid paraffin was evaluated using a four-ball tester and a ring-on-block machine. The relationship between performance and concentration was analysed, and the results showed that the compound possesses good anti-wear, friction-reducing and load-carrying properties. The mechanism of action of the additive was investigated using X-ray photoelectron spectroscopy. Surface analysis indicated the formation of a protective film containing borate, Fe(3)O(4), and an organonitrogen compound. This protective film formed during sliding processes contributes to the increase in wear resistance. Copyright (C) 2010 John Wiley & Sons, Ltd.

WEAKLY NORMAL SUBGROUPS OF FINITE GROUPS

A generalized normality CISE of subgroups of a finite group is introduced. Let F be a saturated formation containing the class of all supersolvable groups. We give a characterization of F by using CISE-normality of subgroups.