采用自动前处理LC/MS进行血浆中药物的快速分析

药物研究的发展对高通量的样品处理分析提出了越来越高的要求,减少样品制备时间和分析时间是解决问题的关键。我们新近发展了一种具有在线稀释旁路和新的样品预处理柱的Shim-Pack MAYI-ODS自动柱切换HPLC和LC／MS系统,该系统无需样品前处理,可直接进样进行血浆、血清中的药物分析。本文利用自动样品前处理LC／MS系统,用ODS整体柱实现了血浆中药物的快速分析。包括样品预处理,整个分析仅需1．2min完成。     

Variable photonic crystal fiber optical attenuator combining air hole reduction induced radiation and bending loss

Recently, an optical attenuator has been important in fiber optic communication systems, because a transmission power in fiber has become higher due to a channel increment in wavelength division multiplexing transmission. A photonic crystal fiber (PCF) optical attenuator is fabricated by air hole diameter reduction in a part of PCF in which radiations are caused in the air hole diameter reduced part of PCF. A PCF optical attenuator has a high power resistance feature due to its radiation-induced operation of optical attenuation. In this paper, we proposed a variable PCF optical attenuator in which a bend was applied to the air hole diameter reduced part in PCF optical attenuator that was fabricated by CO₂ laser irradiation. In PCF optical attenuator fabrication, the attenuation was adjusted by the reduced air hole diameter with laser irradiation time control. It was demonstrated that 10.6–13.5 dB of variable attenuation was obtained at 1550 nm-wavelength with 0°–90° bending angle applied to the air hole diameter reduced part in PCF optical attenuator.     

Historical cohort studies in three arsenic poisoning areas in japan

The results of historical cohort studies of three arsenic poisoning incidents in Japan are presented. The first episode was in a small mountainous community near an arsenic mine and refinery, at Toroku, where patients with chronic arsenism were certified by application of the Pollution Health Damage Compensation Law. The second area was in a small town, Namiki-cho, near Nakajo-machi, where wells were poisoned by arsenic produced in an arsenic(III) sulfide factory. As to the third cohort, eight residents of Nishikawa-machi who ingested well-water suffered arsenic poisoning about 35 years ago. The standardized mortality ratios were used in analyzing these data. Excesses of cancer mortality, especially lung cancer, were observed among the subjects in these areas. In Japan, there are many arsenic poisoning episodes, involving for example soy-sauce poisoning, powdered-milk poisoning and other incidents associated with arsenic mines. Thus it is necessary to clarify the chronic effects of arsenic in these areas.     

Nonstatic solutions for the repulsive massless scalar field Einstein equation

Presented in this paper are exact nonstatic solutions for the coupled repulsive sourceless massless scalar field and the gravitational field. The solutions have the same form as the spatially conformally flat static metricds ² =e ^2ψ dt ² +e ^?2ψ(dx ² +dy ² +dz ²).     

Statistical thermodynamics of polymer solutions. VI. Comblike branched molecules with branches placed randomly along the backbone

Thermodynamic interactions between arbitrarily branched flexible “comb” molecules (with branches of uniform length affixed to backbones of uniform length but with the number of branches on a molecule and their placement arbitrary) are treated by Zimm's perturbation method to obtain results valid to the double contact approximation. Thus, bimolecular cluster configurations with one and two intermolecular contacts, but not more, are correctly accounted for. This general result is applied to “random” combs (with the number of branches per comb uniform, but the placement random) and to “heterogeneous” combs (with both the number of branches on a molecule and their placement random). Results for the random combs are very similar to those reported earlier for “symmetrical” combs (with f uniform branches disposed at points along the backbone chain so as to subdivide it into f + 1 equal sections), but the second virial coefficient for the random model is slightly the larger when the number of branches per chain is small and the fraction of the molecule in the backbone is at least a few per cent. Since random combs are uniform in mass, the osmotic pressure and light-scattering second virial coefficients are alike; but for a system of heterogeneous combs the virial coefficients differ from one another, and from the random comb result, when the mean number of branches f? per chain is small and they are of appreciable length in comparison to the backbone. This behavior reflects the heterogeneity in both molecular mass and dimensions existing under these circumstances. As f? increases and/or the mean fraction of segments in the chain backbone becomes large, coincidence with the random comb result is approached. The double-contact second virial coefficients for both random and heterogeneous combs are obtained in closed analytical expression that are much more easily reduced to numerical results than the expression for symmetrical combs given earlier. These two models also correspond better than the symmetrical combs to materials actually obtainable.     

Annelation of α,β-unsaturated esters to thian-3-one 1-oxides using dianion of ω-(methylsulfinyl)acetophenone

β-Monosubstituted α,β-unsaturated esters undergo an annelation with dilithio salt of ω-(methylsulfinyl)-acetophenone to produce 5-substituted 6-benzoylthian-3-one 1-oxides.     

电极耦接变化对分子器件电子输运特性影响的研究

利用基于Green函数的 Tight-binding 理论,对phenalenyl构成的单分子器件电极耦接点变化情况下的电子输运特性进行了研究.通过理论计算,得出了分子与原子线电极间接点变化对电子输运的影响.结果显示电子通过phenalenyl分子器件的概率随着分子与电极的耦合点的变化而改变.当耦接点改变时,不仅电子通过phenalenyl分子的概率变化,而且无源正负能量开关器件的特征也发生变化.所得结果还揭示出在应用phenalenyl分子器件时,只需改变电极耦接,就可以获得具有不同电子学特性的分子器件.     

Characteristics of Fused Optical Fiber Grating Couplers with Tapered Shapes

Fused optical fiber grating couplers (FGCs), in which Bragg gratings are written in the coupling regions of fused optical fiber couplers with tapered shapes along them are theoretically and experimentally investigated. By coupled mode analysis considering these tapered shapes, the drop efficiencies of the FGCs, which are inherently zero for the normal fiber couplers without grating, are calculated. The grating offset, which is the difference between the centers of grating and the coupler taper, is found to be effective to increase the drop efficiency of the FGC. It is determined that the tapered shapes influence the wavelength dependence of the drop efficiency and tolerate the grating offset precision. Apodizations for the grating of FGC are found to be effective in suppressing side lobes of the drop efficiency. Measurement of the wavelength characteristics of drop efficiency and the temperature characteristics of drop wavelength of the fabricated fused FGC confirm that the lightwave with specific wavelength can be dropped by the FGC and that the temperature dependence of the drop wavelength is similar to that of Bragg wavelength changes of usual fiber Bragg gratings.