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41.
C.J. Powell N.E. Erickson T.E. Madey 《Journal of Electron Spectroscopy and Related Phenomena》1979,17(6):361-403
We report results of a round robin involving binding-energy (BE) and relative-intensity measurements on high-purity samples of gold and copper by X-rayWe have conducted an extensive round robin involving ESCA or XPS measurements on high-purity samples of Ni, Au, and Cu. The Ni sample was used to estabThis round robin had three principal objectives. First, it was intended to assess the overall accuracy of BE and intensity measurements in XPS measuremSecond, it was intended to establish an empirical intensity calibration of one type of XPS instrument versus another from the reported intensity ratiosThird, it was desired to determine the peak position and peak shape for the carbon 1s photoelectron line originating for “adventitious” carbonaWe have made an extensive analysis of trends in the BE and intensity data. We have computed deviations of individual BE measurements from the median vaThe two types of plots just described based on BE and intensity data can be regarded as “response functions” that describe the performance of indivWe have invoked Occam's Razor to distinguish instruments with response functions which vary monotonically with electron energy from those instruments wThe reported spreads in BE and relative-intensity data reported here indicate that improved calibration and operating procedures are required for XPS m 相似文献
42.
John A. Taylor Peter E. Tannenwald Neal R. Erickson Gerald F. Dionne James F. Fitzgerald 《International Journal of Infrared and Millimeter Waves》1985,6(8):687-695
A compact, solid state submillimeter-wave heterodyne radiometer has been developed and was used to measure spectral characteristics of a water vapor jet in a space simulation chamber. Features of the 557 GHz water vapor line profile were observed in significantly greater detail than in previous experiments through an increased sensitivity and improved frequency resolution (600 kHz). The local oscillator of the radiometer consisted of a frequency multiplication chain which was driven by an InP Gunn oscillator at 92.6 GHz, and which contained a frequency tripler and harmonic mixer in cascade. The front end of the receiver had a noise temperature of 4500 K (DSB) at 555 GHz, consumed 3 W and weighed 3 kg. This advance in technology is particularly relevant to submillimeter-wave radiometry from a space-based platform. 相似文献
43.
To each finite multiset , with underlying set , we associate a new multiset , obtained by adjoining to the multiplicities of its elements in . We study the orbits of the map under iteration, and show that if consists of nonnegative integers, then its orbit under converges to a cycle. Moreover, we prove that all cycles of over are of length at most , and we completely determine them. This amounts to finding all systems of mutually describing multisets. In the process, we are led to introduce and study a related discrete dynamical system on the set of integer partitions of for each . 相似文献
44.
45.
B. Josephson G. Jungner J. G. Reinhold D. W. Wilson L. Cuny Y. Abe S. Kawaguchi A. v. Christiani V. Anger O. Rosenheim R. Ehrström K. Täufel H. Thaler G. Widmann E. Kirk W. R. Bloor H. H. Williams B. N. Erickson I. Avrin S. S. Bernstein I. G. Macy G. Ellis L. A. Maynard R. N. Chopra A. C. Roy R. Feulgen H. Grünberg K. Imhäuser C. A. Grau V. Oliva E. Epstein H. Lieb 《Analytical and bioanalytical chemistry》1941,122(3-4):149-160
46.
Erin W. Chambers ric Colin de Verdire Jeff Erickson Francis Lazarus Kim Whittlesey 《Computational Geometry》2008,41(1-2):94
Let be an orientable combinatorial surface. A cycle on is splitting if it has no self-intersections and it partitions into two components, neither of which is homeomorphic to a disk. In other words, splitting cycles are simple, separating, and non-contractible. We prove that finding the shortest splitting cycle on a combinatorial surface is NP-hard but fixed-parameter tractable with respect to the surface genus g and the number of boundary components b of the surface. Specifically, we describe an algorithm to compute the shortest splitting cycle in (g+b)O(g+b)nlogn time, where n is the complexity of the combinatorial surface. 相似文献
47.
We prove necessary and sufficient conditions for the almostsure convergence of the integrals
and thus of ,where Mt = sup{|Xs|: s t} is the two-sided maximum processcorresponding to a Lévy process (Xt)t 0, a(·)is a non-decreasing function on [0, ) with a(0) = 0, g(·)is a positive non-increasing function on (0, ), possibly withg(0 + ) = , and f(·) is a positive non-decreasing functionon [0, ) with f(0) = 0. The conditions are expressed in termsof the canonical measure, (·), of the process Xt. Thespecial case when a(x) = 0, f(x) = x and g(·) is equivalentto the tail of (at zero or infinity) leads to an interestingcomparison of Mt with the largest jump of Xt in (0, t]. Some results concerning the convergence at zero and infinityof integrals like t g(a(t) + |Xt|) dt, t g(St) dt,and t g(Rt) dt, where St is the supremum process and Rt= St Xt is the process reflected in its supremum, arealso given. We also consider the convergence of integrals suchas , etc. 相似文献
48.
Taboada L Prieto L Vidal P Espinosa JF Erickson JA 《Journal of combinatorial chemistry》2007,9(5):748-755
Here we describe a multistep solid-phase synthetic approach for the addition of amino acid residues to both the C- and N-termini of a phenylstatine core, yielding a library aimed at the development of structure-activity relationships in the S2 and S2' regions of the aspartyl proteases. Optimization of the synthetic strategy was performed on the basis of the in situ analysis of the compounds bound to the solid support through high-resolution magic angle spinning NMR Spectroscopy (HR-MAS NMR). 相似文献
49.
Optofluidics offers a number of potentially transformative advantages for photonic systems. At present however there are a number of technological roadblocks that prevent the practical integration of liquid-state elements into traditional high-speed solid-state photonic systems. Two of the most important of these are the need for continuous resupply of liquids and the difficulty in shuttling light between the liquid- and solid-states. In this paper we present an integrated system that solves both these problems. For the first time we demonstrate direct evanescent and end-fire coupling between liquid- and solid-state waveguides and an on-chip fluid core/cladding separation and recirculation system that reduces the consumption of liquids more than 200 fold over the state of the art. The device is operated continuously for over 20 h without performance degradation or requiring the replenishment of liquids. We believe that our system represents an important step towards the development of practical optofluidically enabled photonic systems. 相似文献
50.
EE Jung M Kalontarov DF Doud MD Ooms LT Angenent D Sinton D Erickson 《Lab on a chip》2012,12(19):3740-3745
Microalgae are a promising feedstock for sustainable biofuel production. At present, however, there are a number of challenges that limit the economic viability of the process. Two of the major challenges are the non-uniform distribution of light in photobioreactors and the inefficiencies associated with traditional biomass processing. To address the latter limitation, a number of studies have demonstrated organisms that directly secrete fuels without requiring organism harvesting. In this paper, we demonstrate a novel optofluidic photobioreactor that can help address the light distribution challenge while being compatible with these chemical secreting organisms. Our approach is based on light delivery to surface bound photosynthetic organisms through the evanescent field of an optically excited slab waveguide. In addition to characterizing organism growth-rates in the system, we also show here, for the first time, that the photon usage efficiency of evanescent field illumination is comparable to the direct illumination used in traditional photobioreactors. We also show that the stackable nature of the slab waveguide approach could yield a 12-fold improvement in the volumetric productivity. 相似文献