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Quantification techniques of mass-separation and ion yield for the detection of radioactive isotopes
Dion Michael P. Eiden Gregory C. Farmer Orville T. Finch Zach Liezers Martin Thomas May-Lin 《Journal of Radioanalytical and Nuclear Chemistry》2019,319(3):937-944
Journal of Radioanalytical and Nuclear Chemistry - This research demonstrates two methods of quantifying ion yield efficiency using an inductively coupled plasma mass spectrometer. The mass... 相似文献
24.
Cordes DB Gamsey S Sharrett Z Miller A Thoniyot P Wessling RA Singaram B 《Langmuir : the ACS journal of surfaces and colloids》2005,21(14):6540-6547
The fluorescence sensing of several monosaccharides using boronic acid-substituted viologen quenchers in combination with the fluorescent dye pyranine (HPTS) is reported. In this two-component sensing system, fluorescence quenching by the viologen is modulated by monosaccharides to provide a fluorescence signal. A series of viologen quenchers with different charges were prepared and tested for their ability both to quench the fluorescence of HPTS and to sense changes in glucose concentration in aqueous solution at pH 7.4. Both quenching efficiency and sugar sensing were found to be strongly dependent upon viologen charge. The molar ratio between HPTS and each of the viologen quenchers was varied in order to obtain an optimal ratio that provided a fairly linear fluorescence signal across a physiological glucose concentration range. Both the quenching and sugar sensing results are explained by electrostatic interaction between dye and quencher. 相似文献
25.
The Monodromy Conjecture asserts that if c is a pole of the local topological zeta function of a hypersurface, then exp(2πic) is an eigenvalue of the monodromy on the cohomology of the Milnor fiber. A stronger version of the conjecture asserts that
every such c is a root of the Bernstein-Sato polynomial of the hypersurface. In this note we prove the weak version of the conjecture
for hyperplane arrangements. Furthermore, we reduce the strong version to the following conjecture: −n/d is always a root of the Bernstein-Sato polynomial of an indecomposable essential central hyperplane arrangement of d hyperplanes in C
n
. 相似文献
26.
Peter Sutherland Anthony Rossini Thomas Lumley Nicholas Lewin-Koh Julie Dickerson Zach Cox 《Journal of computational and graphical statistics》2013,22(3):509-529
Abstract This article describes constructing interactive and dynamic linked data views using the Java programming language. The data views are designed for data that have a multivariate component. The approach to displaying data comes from earlier research on building statistical graphics based on data pipelines, in which different aspects of data processing and graphical rendering are organized conceptually into segments of a pipeline. The software design takes advantage of the object-oriented nature of the Java language to open up the data pipeline, allowing developers to have greater control over their visualization applications. Importantly, new types of data views coded to adhere to a few simple design requirements can easily be integrated with existing pipe sections. This allows access to sophisticated linking and dynamic interaction across all (new and existing) view types. Pipe segments can be accessed from data analysis packages such as Omegahat or R, providing a tight coupling of visual and numerical methods. 相似文献
27.
Degradation of poly(β‐amino ester) gels in alcohols through transesterification: Method to conjugate drugs to polymer matrices 下载免费PDF全文
Prachi Gupta Caroline Lacerda Vinod S. Patil Dipti Biswal Paritosh Wattamwar J. Zach Hilt Thomas D. Dziubla 《Journal of polymer science. Part A, Polymer chemistry》2017,55(12):2019-2026
Poly(β amino ester) (PβAE) polymers have received growing attention in the literature, owing to their ease of synthesis, versatile co‐monomer selection, and highly tunable degradation kinetics. As such, they have shown extensive potential in many biomedical applications as well. In this work, it is demonstrated for the first time that PβAE polymers containing primary and secondary amine groups can undergo degradation by primary alcohols via transesterification mechanism. While this work emphasizes an important aspect of solvent compatibility of these networks, it also represents an interesting, simple mechanism for post synthesis drug incorporation, with riboflavin conjugation being demonstrated as a model compound. © 2017 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2017 , 55, 2019–2026 相似文献
28.
A novel approach realizing an optical spectrum analyzer for photonic detection of an unknown RF carrier signals is presented. The described module may be part of an electronic warfare system in which detection of a narrow band RF signal is required. Moreover, The RF signal is characterized by an unknown time varying carrier frequency embedded in wide band noise. The system uses a passive, fiber based photonic configuration. It allows the spectrum mapping of an incoming electronic RF signal modulated on an optical carrier. The spectral analyzer configuration uses a finite impulse response (FIR) filter that is realized by two different optical paths of parallel fibers which generate a spectral notch filter. Hence, a wavelength coding is realized by chromatic dispersion such that each wavelength is filtered by a different FIR filter. Therefore, the energy at a WDM demux output channels is actually proportional to the spectrum of the input RF signal. This spectral mapping is obtained without lose of temporal RF information. 相似文献
29.
M. Weispfenning F. Zach W. Prettl 《International Journal of Infrared and Millimeter Waves》1988,9(12):1153-1171
The magneto-photoconductivity due to 1s-2p+ optical transitions of shallow donors in n-GaAs has been investigated as a function of intensity for several bias voltages at low temperatures between 2K and 4.2 K. At low intensities a superlinear increase of the photoconductive signal with rising intensity has been observed which gets more pronounced at higher bias voltages and lower temperatures. The power broadening of the linewidth was found to be distinctly different from the behaviour expected for a two-level system. By a detailed analysis in terms of a nonlinear generation-recombination model it is shown that these effects may be attributed to impact ionization of the optically excited 2p+ states. 相似文献
30.
P. Zach 《Journal of Polymer Science.Polymer Physics》1972,10(12):2379-2390
The band structure of an infinite linear polyaniline is investigated by using the HCO approximation. The degree of modelling of the limiting structure for the series by the linear oligomers so far synthesized is investigated. The upper bound of the wave-length of the long-wave ultraviolet absorption band for the limit is found, and the possibility of estimation of the conduction properties of its complex with iodine is indicated. The problem of replacement of the NH group in the chains by a more general group X is dealt with, and the dependence of the energy gap between the highest occupied and the lowest unoccupied band on the parameters of this group is determined. 相似文献