Dilution effects on X-ray photoelectron spectra of La<Subscript>0.8</Subscript>Sr<Subscript>0.2</Subscript>MnO<Subscript>3</Subscript> with SiO<Subscript>2</Subscript>

Diluted samples of La_0.8Sr_0.2MnO₃ with SiO₂ were prepared by calcination of the MCM-41 molecular sieve soaked in precursor solutions with various concentrations (0.1, 0.05 and 0.005 mol/l). The diluted samples from the 0.1, 0.05 and 0.005 mol/l solutions showed ferromagnetic behavior in temperature dependent magnetic susceptibility below 300, 250 and 100 K, respectively. The electron binding energy of the La 3d_5/2 main peak of the diluted samples from the 0.1, 0.05 and 0.005 mol/l solutions were 835.7, 836.0 and 837.4 eV, respectively, and were larger than that of La_0.8Sr_0.2MnO₃ bulk sample (834.2 eV). Reduction in intensity of the La 3d charge-transfer satellite was more pronounced for more diluted sample. The Mn 2p_3/2 main peak of all the diluted samples remained at 642.2 eV, which is larger by 0.6 eV than that of the bulk sample (641.6 eV). The charge-transfer peak energy in the optical absorption spectra was the same (2.3 eV) for all the diluted samples, and the energy was larger by 0.4 eV than the bulk one (1.9 eV). The dilution caused localization of charge carriers within the La_0.8Sr_0.2MnO₃ lattices isolated by the insulator. Suppression of charge flow between the isolated La_0.8Sr_0.2MnO₃ lattices resulted in the enlargement of the La 3d electron binding energy and the decrease of the La 3d charge-transfer satellite peak intensity, and also the lowering of the ferromagnetic ordering temperature. © Springer Science + Business Media, Inc.     

Combined use of photocatalyst and adsorbent for the removal of inorganic arsenic(III) and organoarsenic compounds from aqueous media

A novel method for the removal of inorganic arsenic(III) (As(III)), monomethylarsonate (MMA), and dimethylarsinate (DMA) from aqueous media, was proposed and investigated. This method involves the combined use of TiO₂-photocatalyst and an adsorbent, which has a high ability of As(V) adsorption, under photo-irradiation. When an aqueous solution of As(III) was stirred and irradiated by sunlight or xenon lamp in the presence of TiO₂ suspension, the oxidation of As(III) into As(V) was effectively attained. By use of the same photocatalytic reaction, MMA and DMA were also degraded into As(V), while the total organic carbon (TOC) in the aqueous phase was decreased. When an aqueous solution of As(III) was stirred with a mixed suspension of TiO₂ and an adsorbent for As(V) (activated alumina) under sunlight irradiation, the arsenic removal reached 89% after 24 h. By use of the same photocatalyst–adsorbent system, 98% of MMA and 97% of DMA were removed. The mechanism of the removal of arsenic species by the photocatalyst–adsorbent system was discussed.     

Analysis of lipoproteins by microchip electrophoresis with high speed and high reproducibility

A method for the fast analysis of lipoproteins by microchip electrophoresis with light-emitting diode confocal fluorescence detection has been developed. Lipoproteins labeled with BODIPY FL C(5)-ceramide are found to strongly adsorb on the bare surface of a poly(methyl methacrylate) (PMMA) microchip. Sodium dodecyl sulfate and cetyltrimethylammonium bromide were therefore utilized to alter lipoproteins and channel surface to make them bear the same type of charge. After modification, the peak shape of lipoproteins was greatly improved, demonstrating lipoprotein adsorption on a PMMA chip dramatically reduced due to electrostatic repulsion. In addition, polymers were added into the running buffer to suppress electroosmotic flow and to serve as a sieving matrix. As a result, lipoprotein separation was manipulated by both electrophoretic mobilities and particle sizes. Various separation parameters including surfactant concentration, buffer pH, and polymer concentration as well as on-line concentration were investigated systematically. Under optimal conditions, two baseline separations of standard lipoproteins including high-density lipoprotein, low-density lipoprotein, and very low-density lipoprotein were achieved with different selectivity. This method affords high separation speed (within 100 s) and high reproducibility. The intraassay and interassay RSDs of lipoprotein migration times were in the range of 0.90-1.9%, indicating this method is highly reliable.     

Simple atmospheric transmittance calculation based on a Fourier-transformed Voigt profile

A method of line-by-line transmission calculation for a homogeneous atmospheric layer that uses the Fourier-transformed Voigt profile is presented. The method is based on a pure Voigt function with no approximation and an interference term that takes into account the line-mixing effect. One can use the method to calculate transmittance, considering each line shape as it is affected by temperature and pressure, with a line database with an arbitrary wave-number range and resolution. To show that the method is feasible for practical model development, we compared the calculated transmittance with that obtained with a conventional model, and good consistency was observed.     

Synthesis of longitudinal coherence functions by spatial modulation of an extended light source: a new interpretation and experimental verifications

Giving a new physical interpretation to the principle of longitudinal coherence control, we propose an improved method for synthesizing a spatial coherence function along the longitudinal axis of light propagation. By controlling the irradiance of an extended quasi-monochromatic spatially incoherent source with a spatial light modulator, we generated a special optical field that exhibits high coherence selectively for a specific pair of points at specified locations along the axis of beam propagation. This function of longitudinal coherence control provides new possibilities for dispersion-free measurements in optical tomography and profilometry. A quantitative experimental proof of principle is presented.     

Solving and visualizing nonlinear parametric constraints in control based on quantifier elimination

We present a new method with a software tool for parametric robust control synthesis by symbolic-numeric computation. The method is a parameter space approach and it is especially effective for analysis and design of fixed-structure controllers of rational type, which encompass PI and PID controllers. The real quantifier elimination (QE), which is one of the recent progresses in the symbolic computation, plays a key role in our development. The QE-based approach can uniformly deal with a lot of important design specifications for robust control such as frequency restricted H _∞ norm constraints, stability (gain/phase) margin and stability radius specifications, and pole location requirement by reducing such specifications to a particular type of formulae called a “sign definite condition (SDC)”. This is also useful for improving the efficiency of QE computations since we can utilize an efficient QE algorithm specialized to the SDC using the Sturm-Habicht sequence. We have developed a MATLAB toolbox for robust parametric control based on a parameter space approach accomplished by QE. The QE-based parameter space approach and numerical simulation of performances for specific controller parameter values taken from a controller parameter space are integrated conveniently in our toolbox with the assistance of a graphical user interface (GUI). With our toolbox the feasible regions of controller parameters are visualized in a parameter space for the controllers with three or two parameters. This enables control engineers to achieve multi-objective robust controller synthesis smoothly. We also discuss how to merge the numerical computation and the symbolic operation to make our new design methods more efficient in practical control design.     

Compatibility of U-67590A Sterile Solution with Normal Saline, Dextrose Solution, and Solita-T No. 3 with or without Aminophylline Injectable

The compatibility of U-67590A sterile solution (SS) with three drip fluids (normal saline, 5% dextrose solution, and Solita-T No. 3) and Neophylline^R (an aminophylline injectable) was studied. The entire volume of U-67590A SS in an ampoule was transferred into each of the drip fluid containers (500 mL fill). The container was laid under fluorescent light (ca. 1,200 lux) at room temperature. The physical appearance (color and precipitates), pH, U-67590A concentration, and degradation impurity levels were examined for 24 hr. The chemical and physical stability of U-67590A in these drip fluids was adequate enough so that any one of the three can be used for U-67590A administration. However, the stability was reduced when aminophylline co-existed in the admixtures because of increased pH levels. In this case, the stability depended on the strength of U-67590A SS added and the drip fluid used. In terms of chemical stability, Solita-T No. 3 was most favorable when admixed with aminophylline injectable. The fastest degradation was observed in normal saline containing aminophylline. This instability was caused by the higher ionic strength. Dextrose did not seem to affect the stability of U-67590A significantly. The Solita-T No. 3 admixture had the lowest pH, thereby overcoming the negative effect of ionic strength and giving the highest stability among the three admixtures. The stability of U-67590A in direct admixture with Neophylline^R also depended on the strength of U-67590A; the stability increased with strength of U-67590A.     

Specialty polymeric membranes. V. Selective permeation of carbon dioxide through synthetic polymeric membranes having 2-(N,N-dimethyl)aminoethoxycarbonyl moiety

Permeation of CO₂ was investigated by using synthetic polymeric membranes having a tertiary amine moiety, 2-(N,N-dimethyl)aminoethoxycarbonyl moiety. Permselectivity of the present membranes towards CO₂ was achieved. Through poly{2-(N,N-dimethyl)aminoethyl methacrylate-co-acrylonitrile} (DMAEMA/AN-199) membrane, where DMAEMA mol fraction was 0.199, the separation factor towards CO₂ for CO₂/N₂ separation ranged from 60 to 90, ranging in the CO₂ partial pressure in the feed gas from 61 to 3.6 cmHg. © 1995 John Wiley & Sons, Inc.     

Autonomous decentralized control and its application to the rapid transit system

A large scale control system has three intrinsic requirements of fault tolerance, on-line extension and maintenance for non-stop operation. For attaining these requirements, the new design philosophy for autonomous decentralized control system, called HAL (Harmonous, Autonomous and Localities) concept, has been proposed based on the biological analogy.The viewpoint of this concept is that it is quite normal for a system to have failed parts.Sufficient conditions for an autonomous decentralized control system are given that every subsystem is uniform and equal in function and structure, and utilizes only local information for control and coordination.As one of the applications to the system components of this new concept, ADL-Net (Autonomous Decentralized Loop Network) has been developed, where fault tolerance of the system is attained by giving autonomy for fault detection, recovery and transmission to every network control processor.The HAL concept has also been applied to the train traffic control system for subways with three intrinsic requirements for supporting their non-stop operations.