Banach空间中非线性$\Phi$-伪压缩映象不动点的迭代逼近

本文研究了非线性拟$\Phi$-伪压缩映象与$\Phi$-伪压缩映象的不动点的迭代逼近问题.研究结果表明: 在任意实的Banach空间$E$中,拟$\Phi$-伪压缩映象与$\Phi$-伪压缩映象$T$~($T$不必连续)的具误差的Ishikawa与Mann迭代序列强收敛于$T$的唯一不动点.所得结果不但改进和推广了最近一些文献的相关结果,而且也改进了定理的证明方法.     

流动注射-化学发光法测定非洛地平

基于非洛地平在碱性条件下对鲁米诺-K3Fe(CN)6化学发光体系具有很强的增敏作用,结合流动注射技术,建立了直接测定非洛地平的流动注射-化学发光新方法.方法的线性范围为6.0×10(-9)～3.0×10(-6)g/mL,检出限为2.1×10(-9)g/mL,对浓度为1.0×10(-7)g/mL非洛地平平行测定11次,其...     

Study of spatial distribution for the active ingredient in ibuprofen tablet based on near-infrared micro-imaging technology

The NIR micro-images of ibuprofen tablets were collected in this research.Compare correlation imaging and principal component analysis(PC A) with histogram were applied to acquire the spatial distribution of ibuprofen granule.The result indicated that a similar distribution trend can be acquired by both of the two methods mentioned above;the information of PC2 results from ibuprofen mainly since the correlation coefficient between PC2 loading vector and the NIR spectrum of ibuprofen is 0.9930.The result of PCA indicated that the information of PC2 results from ibuprofen mainly for both the low and the high content of ibuprofen in the tablets.The correlation coefficient between the data of the two PC2 loading vectors of the low and the high content of ibuprofen in the tablets is 0.9998,which indicates that the result of PCA is stable and reliable.     

Analysis of Neutral Sugars of Asparagus officinalis Linn. Polysaccharide by CZE with Amperometric Detection

Analysis of the neutral sugars of Asparagus officinalis Linn. polysaccharide by different methods has yielded inconsistent results. In the work discussed in this paper, capillary zone electrophoresis with amperometric detection (CZE–AD) was used for analysis of neutral sugars in A. officinalis Linn. polysaccharide. The configuration of the wall-jet and the diameter of the copper disk electrode were investigated to achieve optimized detection sensitivity. The separation electrolyte, separation voltage, and injection time were studied for their effects on CZE separation. Under the optimum CZE–AD conditions, seven monosaccharides were separated to baseline by using 120 mM NaOH as separation electrolyte. Linear response was excellent and repeatability was satisfactory. It was found that Asparagus polysaccharide was composed of fucose, galactose, glucose, rhamnose, arabinose, fructose, and xylose at a mole ratio of 0.2:16.2:5.0:1.0:15.5:0.6:18.8. Compared with other methods, analysis of the composition of Asparagus polysaccharide by CZE–AD had the merits of rapidness, accuracy, and lower sampling volume.

     

The coupling of rapidly synergistic cloud point extraction with thermospray flame furnace atomic absorption spectrometry

Rapidly synergistic cloud point extraction (RS-CPE) was coupled with thermospray flame furnace atomic absorption spectrometry (TS-FF-AAS) to result in new CPE patterns and accelerated (1?min) protocols. It is demonstrated, for the case of copper (II) ion, that TS-FF-AAS improves the sampling efficiency and the sensitivity of FAAS determinations. Problems of nebulization associated with previous methods based on the coupling of FAAS and RS-CPE are overcome. TS-FF-AAS also improves sensitivity and gives a limit of detection for copper of 0.20?μg?L^-1, which is better by a factor of 32. Compared to direct FAAS, the factor is 114.

Theoretical Study of Origin of Triple Fluorescences of a Squaraine Dye, Bis[4-(N,N-dimethylamino)phenyl]-squaraine

A new scheme of photo‐fluorescent emission origin, described as S₀ (relaxed state)→S_n (Frank‐Condon state)→ S_m (relaxed state)→S₀ (Frank‐Condon state), is presented to explain the multiple fluorescent emissions of squaraine dyes observed experimentally according to the configuration interaction singles calculations of relaxed excited states of a model compound, bis[4‐(N,N‐dimethylamino)phenyl]squaraine (SQ). It is exhibited that all triple fluorescent emissions of SQ have their significant origin in vertical electron transitions of different relaxed excited states. In addition, some important absorption peaks appearing in higher energy region are most likely to be responsible for the higher energy band observed in solid states of many squaraine dyes.     

关于增生算子方程的具误差的Ishikawa迭代序列的收敛率估计

设X是一实的Banach空间,TLX→X是—Lipschitz的增生算子;证明了具误差的Ishikawa迭代序列强收敛到x＋Tx=f的唯一解;得到一个一般的收敛率估计式．进一步得到：若了T：X→X是—Lipschitz的强增生算子,则具误差的Ishikawa迭代序列强收敛到Tx=f的唯一解．文中结果推广和发展了已有的相关结果．     

Superconductivity and calorimetric studies of Pr1.85Ce0.15CuO4+δ under different annealing conditions

Polycrystalline samples of electron-doped Pr_1.85Ce_0.15CuO_4+δ have been prepared under different annealing conditions and investigated by means of X-ray-diffraction, oxygen content analysis, electrical resistivity, magnetic susceptibility and low temperature specific heat measurements. X-ray-diffraction patterns show that samples contain a single T′ phase. The superconducting transition temperatures T_cm taken with the onset of diamagnetism in magnetic-susceptibility measurements are 20 and 19.5 K for sample annealed in flowing Ar gas and in vacuum (∼10⁻³ torr), respectively. The data of the samples, which are annealed in flowing Ar gas, show clear evidence for an αT² term at zero magnetic field in superconducting electronic specific heat, and are consistent with d-wave superconductivity. However, this behavior is not observed in the other sample, which is annealed in vacuum. These results indicate that different heat treatments affect the oxygen content, homogeneity, superconducting transition temperature T_c, superconducting volume fraction, and the superconducting pairing symmetry of Pr_1.85Ce_0.15CuO_4+δ.     

Minimum polarizability principle applied to lowest energy isomers of some gaseous all-metal clusters

In comparison with the minimum energy criterion as an indicator of the most stable state, the minimum polarizability and maximum hardness principles have been examined to describe the relative stability of various isomers of nine gaseous all-metal clusters M4X- (Cu4Na-, Cu4Li-, Al4Cu-, Ag4Li-, Au4Li-, Ag4Na-, Au4Na-, Al4Ag-, Al4Au-) on the basis of MP2 calculations. In these species, there are two lowest energy isomers with near isoenergy that sometimes make it very difficult to determine which of them is more stable when we depend only on the minimum energy criterion. According to the minimum polarizability principle, however, the square-pyramidal structure is always more stable than the planar isomer at various computational levels, which was also confirmed by the results from the minimum energy principle that sometimes requires higher computational precision. Thus, there is an indication that, at least for our present cluster system, the minimum polarizability principle is less dependent on the computational levels compared to the minimum energy principle.     

超凸度量空间中非扩张可交换映象族的几乎不动点

获得了关于超凸度量空间中非扩张可交换映象族不动点存在性的更一般结果.证明了可数个非扩张可交换映象的公共ε-几乎不动点集的超凸性,并在一定条件下证明了任意个非扩张可交换映象的公共ε-几乎不动点集的超凸性.还讨论了Baillon的两个重要结果间的等价关系.