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81.
Surface plasmon propagating modes supported by metal/dielectric interfaces in various configurations can be used for radiation guiding similarly to conventional dielectric waveguides. Plasmonic waveguides offer two attractive features: subdiffraction mode confinement and the presence of conducting elements at the mode‐field maximum. The first feature can be exploited to realize ultrahigh density of nanophotonics components, whereas the second feature enables the development of dynamic components controlling the plasmon propagation with ultralow signals, minimizing heat dissipation in switching elements. While the first feature is yet to be brought close to the domain of practical applications because of high propagation losses, the second one is already being investigated for bringing down power requirements in optical communication systems. In this review, the latest application‐oriented research on radiation modulation and routing using thermo‐optic dielectric‐loaded plasmonic waveguide components integrated with silicon‐based photonic waveguides is overviewed. Their employment under conditions of real telecommunications is addressed, highlighting challenges and perspectives.  相似文献   
82.
An equation to be used to budget fuel consumption in a cruise liner is developed. The model building process is described in detail to explain the way in which the results were obtained.  相似文献   
83.
Zusammenfassung Cadmium bildet negativ geladene Jodidkomplexe, die eine Abtrennung dieses Elementes aus dem Harn mit Hilfe eines Anionen-austauschers ermöglichen. Elution vom Austauscher ergibt eine Cadmiumlösung mit nur wenigen Begleitstoffen bzw. einer einheitlichen Matrix, die für eine weitgehend störungsfreie Endbestimmung durch flammenlose Atomabsorptionsspektrometrie verwendet werden kann. Danach beträgt der Normalgehalt an Cadmium im Harn im Mittel 0,78±0,53 ng/ml und liegt im Bereich zwischen 0,22 und 1,7 ng/ml.
A simple method for determination of cadmium in urine
Summary Cadmium can be isolated from urine by formation of negatively charged iodide complexes bound to an anion exchange resin. Elution from the resin gives a cadmium solution with only a few concomitant substances in an uniform matrix. Thus an undisturbed determination by flameless atomic absorption spectrometry is achieved. The mean of the natural cadmium level found in urine was 0.78±0.53 ng/ml, within the normal range between 0.22 and 1.7 ng/ml.
  相似文献   
84.
A new methodology for protein microarray fabrication is proposed based on the ablation of polymer film using laser at 157 nm (F2). The polymer has been selected among others with the criterion of negligible protein adsorption. Improved results have been obtained by pretreatment of the polymer surface with an inert protein. The use of 157-nm laser radiation allowed very good depth control during the polymeric layer ablation process. In addition the importance of laser ablation at 157 nm is based on the fact that irradiated surfaces indicate limited chemical change due to the fact that laser ablation at 157 nm is only photochemical, thus avoiding excessive surface heating and damage. Results of protein microarray fabrication are presented to illustrate the viability of the proposed method.  相似文献   
85.
Summary Three independent decomposition methods for organic matter are compared for use in the determination of arsenic by the hydride-AAS method. Matrix interferences in the arsine evolution cause systematic errors.
Bestimmung von Arsen im ng/g- und g/g-Bereich in organischem und biologischem Material
Zusammenfassung Drei unabhängige Aufschlußmethoden zwecks Arsenbestimmung nach der Hydrid-Atomabsorptionsmethode wurden verglichen. Störungen seitens der Matrix bei der AsH3-Entwicklung sind eine der Ursachen für systematische Fehler.
  相似文献   
86.
We have shown that nanostructured multi-component materials like TaC, Nb78Ge22, Mo70Si20B10, Mo60Os20B20, Ru52Zr6B42, (NbC)20Co80 and (WC)80-(Ti90Cu10)20 with an effective length size reduced to atomic level (a few nanometers) can be produced by mechanical alloying of the elemental and/or alloy powders in a high-energy ball mill. All process steps and samples preparation for characterization were done under glove box conditions.  相似文献   
87.
88.
We consider interpolatory quadrature formulae, relative to the Legendre weight function w(t) = 1 on [–1, 1], having as nodes the zeros of the nth degree Jacobi polynomial P n (, ) plus the points 1 and –1. We show that in specific domains of and gb the weights of these formulae are almost all positive, exceptions occurring only with the weights corresponding to 1 and –1.  相似文献   
89.
90.
Carbotrap was added to a glass beads cryotrap in order to increase the retention of the very volatile two-carbon hydrocarbons, ethylene, ethane and acetylene. Indeed the obtained recoveries increased from 2 to 3% for ethylene, the poorest retained compound, from 7 to 20% for ethane and from 23 to 31% for acetylene between the glass beads only and the Carbotrap/glass beads cryotrap. The addition of the Carbotrap, however, decreased the obtained recovery of o-xylene by 22–46%, depending on the employed conditions. The smaller decrease was observed when the longer desorption time was employed. The variation of the temperature of desorption by 40°C had very little effect on the resulting recoveries.  相似文献   
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