No abstract

No abstract

Let $p$ be an odd prime, and $D_{2p}=\langle a,b\mid a^p=b^2=1,bab=a^{-1}\rangle$ the dihedral group of order $2p$. In this paper, we completely classify the cubic Cayley graphs on $D_{2p}$ up to isomorphism by means of spectral method. By the way, we show that two cubic Cayley graphs on $D_{2p}$ are isomorphic if and only if they are cospectral. Moreover, we obtain the number of isomorphic classes of cubic Cayley graphs on $D_{2p}$ by using Gauss' celebrated law of quadratic reciprocity.Comment: 15 pages, 0 figur

Monoethanolamine (MEA) was investigated as corrosion inhibitors of a 6063 aluminum alloy in 3.5 % solution using polarization and electrochemical impedance spectroscopy techniques and weight loss. The polarization curves show that monoethanolamine (MEA) can increase corrosion potential (Ecorr) and pitting corrosion potential (Epit), and decrease corrosion current density (icorr) of the 6063 aluminum alloy. EIS results indicate that monoethanolamine (MEA) can increase impedance of the 6063 aluminum alloy. The results show that monoethanolamine exhibits better inhibitor properties for the 6063 aluminum alloy. Electrochemical test results show monoethanolamine (MEA) can improve corrosion resistance and the inhibition action depends on the concentration of the inhibitor. The weight-loss experiment also proves that monoethanolamine (MEA) can improve the corrosion resistance of the 6063 Al alloy.

Nuclear quadrupole resonance (NQR) is an advanced radio frequency (RF) spectroscopic technique, widely used to analyse substances containing quadrupole nuclei, such as2H,14N,17O,35Cl and39K. In this paper, we focus on the NQR detection of nitrogenous compounds including nucleus Nitrogen-14 or14N. We will briefly introduce its fundamental principles, namely, nuclear quadrupole moment and NQR detection mechanism, and then provide some experimental results based on these theories, such as sodium nitrite, methenamine, urea and thiourea. At last, according to these results, we will make some discussion about the properties of NQR detection.