Every compact group arises as the outer automorphism group of a II1 factor

We show that any compact group can be realized as the outer automorphism group of a factor of type II₁. This has been proved in the abelian case by Ioana, Peterson and Popa [A. Ioana, J. Peterson, S. Popa, Amalgamated free products of w-rigid factors and calculation of their symmetry group, math.OA/0505589, Acta Math., in press] applying Popa's deformation/rigidity techniques to amalgamated free product von Neumann algebras. Our methods are a generalization of theirs.     

Surfactant/oil/water system for the determination of selenium in eggs by graphite furnace atomic absorption spectrometry

An oil-in-water formulation has been optimized to determine trace levels of selenium in whole hen eggs by graphite furnace atomic absorption spectrometry. This method is simpler and requires fewer reagents when compared with other sample pre-treatment procedures. Graphite furnace atomic absorption spectrometric (GF AAS) measurement was carried out using standard addition calibration and Pd as a modifier. The precision, expressed as relative standard deviation, was better than 5% and the limit of detection was 1 µg L^− 1. The validation of the method was performed against a standard reference material Whole Egg Powder (RM 8415), and the measured Se corresponded to 95.2% of the certified value. The method was used for the determination of the Se level in eggs from hens treated with Se dietary supplements. Inorganic and organic Se sources were added to hen feed. The Se content of eggs was higher when hens were fed with organic Se compared to the other treatments. The proposed method, including sample emulsification for subsequent Se determination by GF AAS has proved to be sensitive, reproducible, simple and economical.     

多元统计分析在医院管理中的应用

本文应用多元统计分析中的聚类分析和因子分析法 ,对辽宁省金秋医院内科循环病房 1997- 1999年的月报表进行了综合评价 ,借以说明多元统计分析用于医院管理的实用性与优越性     

Comparison of direct sampling and emulsion analysis using a filter furnace for the determination of lead in crude oil by graphite furnace atomic absorption spectrometry

The determination of trace elements in crude oil is difficult due to the complex nature of the sample and the various different chemical forms in which the metals can occur. The advantage of graphite furnace atomic absorption spectrometry is that only a minimum of sample pretreatment is required. In this work two techniques have been compared to establish a fast and reliable method for lead determination in crude oil. In the first one the crude oil samples were weighed directly onto solid sampling (SS) platforms and introduced into the graphite tube for analysis. In the second one the samples were prepared as oil-in-water emulsions and analyzed in a filter furnace (FF). Twenty μL of a mixture of 0.5 mg L^− 1 Pd + 0.3 mg L^− 1 Mg + Triton X-100 has been used as the modifier, and calibration against aqueous solutions has been used for both methods. The sensitivity obtained with the FF was more than a factor of two better than that with SS; however, as a larger sample mass could be introduced in the latter case, so that the limits of detection for both techniques were 0.004 mg kg^− 1. Seven crude oil samples were analyzed using the two procedures, and all results were in agreement at a 95% confidence level using a paired Student's t-test. For validation purposes, three crude oil samples have been mineralized using an open-vessel acid digestion, and the results were in agreement with those found with direct sampling and with emulsion sampling using FF according to ANOVA test. Both methods are simple, fast and reliable, being appropriated for routine analysis; however, the direct method using SS technology should be preferred because of its simplicity, speed and commercial availability.     

Very efficient two-photon induced photo-tautomerization in non-symmetrical phthalocyanines

In this work we demonstrate that non-symmetrically substituted phthalo-naphthalocyanine molecule can have extremely large 2PA cross section in near-resonance conditions of excitation. We also show the possibility to switch between its two tautomeric forms upon two-photon excitation at 77 K. By measuring 2PA cross section, quantum efficiency of transformation in these two forms, as well as quantum yield of fluorescence, we evaluate the figure of merit for fast re-writable 3D information storage and show that this figure meets the criteria of reliable and fast (one bit per one femtosecond pulse) 2PA writing or reading.     

Analysis of the absorption mechanism during laser-metal interaction

The present study examines the absorption of a laser beam at different wavelengths by a partially-ionized vapour during the interaction mechanism. The applicability of the theoretical models developed is discussed in detail. The interaction of the high- and low-power intensities of a laser beam with plasma is distinguished. It is shown that different metal vapours at similar temperatures and densities have absorption depths which may differ by an order of magnitude. Even more substantial is the difference between the absorption depths of light from different lasers in common use. It is also shown that the free electron temperature becomes significantly different from the heavy particle temperature for power intensities above the critical level which is typically > 10¹⁴W/m². The free electron velocity distribution has an isotropic part which becomes non-Maxwellian for power intensities greater than the critical power intensity.     

O1s and Mn2p NEXAFS on single-layered La1-xSr1+xMnO4: crystal field effect versus orbital coupling mechanism

O1s and Mn2p near-edge X-ray absorption spectroscopy on La_1-xSr_1+xMnO₄ (0 ≤x ≤0.5) single crystals shows that Sr doping does not only provide holes to the system but also induces a continuous transfer of electrons from out-of-plane d_3z2-r2 to in-plane d_3x2-r2/d_3y2-r2 orbitals. Furthermore, a non-vanishing electron occupation of in-plane d_x2-y2 and out-of-plane d_3z2-r2 orbitals is observed up to relatively high doping contents. These findings demonstrate that the energy difference between all these orbital types has to be very small and manifest that the orbital degree of freedom is determined not just by crystal field effects but also by orbital coupling. Moreover, the doping-dependent transfer of spectral weight observed in the current data identifies La_1-xSr_1+xMnO₄ as a charge-transfer insulator.     

环行染料激光器用于内腔吸收光谱的研究

本文报告了利用新型连续波环行染料激光器,即使行波工作于超过阈值两倍以上,仍在大气中获得了近10~5的内腔吸收灵敏放大;并首次利用单频扫描方法,在不降低灵敏放大的同时,得到了10~(-2)的光谱分辨率。实验结果与经改进后的Brunner-Paul理论分析一致。     

Excitonic effects in molecular crystals built up by small organic molecules

The excitonic effects of biphenyl and 2,2′-bithiophene are investigated within an ab initio framework. For this purpose the Bethe–Salpeter equation for the two-particle Greens function is solved. Therefrom the imaginary part of the dielectric function is derived, which includes the electron–hole interaction in the absorption process. It turns out that these organic molecular crystals, which are built by small molecules, give rise to sizeable exciton binding-energies, which are between 0.7 and 0.8 eV. To study the influence of the intermolecular interaction, the exciton binding energy of crystalline biphenyl is calculated as a function of pressure. The decrease of both, the band gap and the exciton binding energy, results in a slight red-shift of the lowest optically active singlet exciton.