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121.
本文讨论AFC^*一代数中的一些映射的线性性质和它们的局部性质之间的关系.研究AFC^*一代数A上的保持乘法的局部自同构Ф在A中矩阵单位系上的作用。证明了Ф是A上的自同构。对于UHF代数上满等距的结构,还证明了UHF代数上的2-局部(满线性)等距是线性的. 相似文献
122.
Gold in ores was determined by flame atomic absorption spectrometry following on-line preconcentration by sorbent extraction in a flow-injection system. The medium polarity adsorption resin Amberlite XAD-8 packed in a 220-μl micro-column was used to collect gold(III) from hydrochloric acid sample solutions for 40 s at 7.6 ml/min. Ethanol was used to elute the adsorbed analytes into the nebulizer. Optimization studies were made on sample loading rate, elution rate and sample acidity. Some possible interferences on the determination are discussed. A 35-fold enrichment was achieved at a sampling frequency of 60 h?1 and with an RSD of 1.4%. The detection limit (3σ) and 2 μg l?1. Results for gold in ore samples showed good agreement with those obtained using activated carbon adsorption preconcentration. The recoveries were 97–108%. 相似文献
123.
本文介绍了利用喷油脉宽大小的变化来分析电控发动机电控系统、燃油供给等系统故障的一种方法,在汽车故障检测与诊断中有着广泛的应用。 相似文献
124.
Features of the total disintegration events of heavyemulsion targets caused by 4.5A GeV/c16O
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Total disintegration events produced by 4.5\,A GeV/c $^{16}$O--AgBr interactions are
analysed to investigate the characteristics of secondary charged particles produced
in such collisions. The multiplicity distributions of grey, black, and relativistic
charged particles can be well represented by Gaussian distribution. The average
multiplicity of grey particles is found to increase with the mass of projectile
increasing, while that of black particles is found to decrease with the mass of
projectile increasing. This result is in good agreement with the prediction of
fireball model. Finally, the linear dependence between grey and black particles is
observed, but there is no distinct dependence between the production of relativistic
charged particles and the target excitation. 相似文献
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A series of complexes formed between halogen-containing molecules and ammonia have been investigated by means of the atoms in molecules (AIM) approach to gain a deeper insight into halogen bonding. The existence of the halogen bond critical points (XBCP) and the values of the electron density (Pb) and Laplacian of electron density (V2pb) at the XBCP reveal the closed-shell interactions in these complexes. Integrated atomic properties such as charge, energy, polarization moment, volume of the halogen bond donor atoms, and the corresponding changes (△) upon complexation have been calculated. The present calculations have demonstrated that the halogen bond represents different AIM properties as compared to the well-documented hydrogen bond. Both the electron density and the Laplacian of electron density at the XBCP have been shown to correlate well with the interaction energy, which indicates that the topological parameters at the XBCP can be treated as a good measure of the halogen bond strength In addition, an excellent linear relationship between the interatomic distance d(X…N) and the logarithm of Pb has been established. 相似文献
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