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201.
James J. Sheng 《Transport in Porous Media》2009,77(3):507-527
To determine the permeabilities from a vertical interference test, earlier investigators proposed correlations or type curves
based on point source solutions or partially penetrated well solutions. However, it is impossible for these correlations or
type curves to cover all possible scenarios in the real world. In more recent years, people use regression analysis to simultaneously
match the pressure responses at the source interval and the observation point. With regression analysis, we face the problem
of non-unique solutions. Sometimes, estimated permeability could be outside a reasonable range when analyzing noisy data from
real tests. In this paper, a new technique is presented to estimate horizontal and vertical permeabilities from the time-delayed
response in a wireline vertical interference test. In a vertical test, a pressure drawdown test period is followed by a pressure
buildup test period. Because of the delay in response, the pressure at the observation probe continues to drop for some time
while the pressure at the source interval is being built up. The maximum pressure drop at the observation probe with regard
to the maximum pressure drop in the source interval is time-delayed. Using this time delay and the maximum pressure drop at
the observation probe, vertical and horizontal permeabilities can be estimated. A novel numerical scheme is used. The new
technique is compared with the previous methods, and it shows its superiority in accuracy. In addition, it can be used in
different test configurations. Application issues in real testing conditions are discussed. Finally, two field tests are analyzed
using this technique, while an earlier effort to analyze the tests using a conventional method was not successful due to poor
data quality. 相似文献
202.
203.
Topographical structures were created on the surface of multi-walled carbon nanotube-based coatings deposited on borosilicate glass using the direct laser interference patterning (DLIP) technique. Films made by multi-walled carbon nanotubes (MWNTs) dispersed in antimony-doped tin oxide (ATO) matrix and networks of MWNTs with both low and high adherence to the substrates were irradiated with one single laser pulse. Due to the high absorption coefficient of ATO, the film was completely removed at the interference maxima positions leading to periodic arrays of high quality on macroscopic areas. Additionally, increase of the laser fluence has produced wider ablated regions. Irradiation of high adherent networks of MWNTs produced a periodic porous structure, what has been attributed to the presence of adherence promoters in the film. On the other hand, MWNT networks with low adhesion to the substrate were strongly removed at the interference maxima positions. In this case, however, the fabricated periodic structures presented several defects that result from the poor adherence of the film to the substrate. 相似文献
204.
G. Indebetouw 《Optics & Laser Technology》1986,18(5)
The reconstruction of coded aperture images using an optical scanning heterodyne processor is described for a class of apertures which can be synthesized by two beam interference. The analysis of Fresnel zone apertures indicates that a lateral and longitudinal (tomographic) resolution close to the theoretical limit is achievable. Experimental results of optical simulations confirm this assertion. Advantages of such technique include real-time operation and large multiplexing capability. 相似文献
205.
206.
Vapor generation-inductively coupled plasma-optical emission spectrometry was used for the determination of sulfide in water samples preserved by the addition of a zinc acetate and sodium hydroxide solution. Hydrogen sulfide and acid-volatile sulfides were transformed, by acidification, to a gaseous phase in a vapor generator and subsequently detected by inductively coupled plasma optical emission spectrometry. Compounds interfering with iodometric titration and spectrophotometric determination were examined as potential chemical interferents. The proposed method provides results comparable to iodometric titration in the tested concentration range 0.06-22.0 mg L−1. Limit of detection for the determination of hydrogen sulfide by this method is 0.03 mg L−1. 相似文献
207.
208.
讨论了菲涅耳双棱镜实验中虚光源的位置,计算了两虚光源间的距离,并进行了实验测量,理论分析与实验相一致. 相似文献
209.
S. Prezioso L. Ottaviano M. Donarelli L. Palladino A. Reale 《Journal of luminescence》2011,131(4):682-6253
A distributed feedback (DFB) waveguide cavity with erbium-tris(8-hydroxyquinoline) has been fabricated by X-ray interference lithography in a laboratory-scale apparatus. The DFB cavity consists of a large area () one-dimensional grating of polymethylmethacrylate on Si (1 0 0). Structural, morphological and optical properties of the device have been studied. On-grating narrowing of the photoluminescence emission has been observed for the 492 nm grating period in correspondence to the 4f-4f Er band peak (at 1530 nm), indicating the possibility of optical gain for applications in the telecommunications. 相似文献
210.
We derive analytical expressions for the single mode quantum field state at the individual output ports of a beam splitter when a single-photon Fock state and a coherent state are incident on the input ports. The output states turn out to be a statistical mixture between a displaced Fock state and a coherent state. Consequently we are able to find an analytical expression for the corresponding Wigner function. Because of the generality of our calculations the obtained results are valid for all passive and lossless optical four port devices. We show further how the results can be adapted to the case of the Mach-Zehnder interferometer. In addition we consider the case for which the single-photon Fock state is replaced with a general input state: a coherent input state displaces each general quantum state at the output port of a beam splitter with the displacement parameter being the amplitude of the coherent state. 相似文献