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71.
P. V. Zrelov V. V. Ivanov 《Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment》1991,310(3):623-630
The statistical method of identification of relativistic charged particles by measurements of ionization losses or time-of-flights simultaneously in some detectors of an experimental plant on the basis of the new goodness-of-fit ωn3-criterion is considered. The method proposed has been used for the secondary particles identification from the high energy -particles fragmentation on target nuclei. The efficiency of the method is excellently illustrated by reliable separation of events (rare events as well), connected with the appearence of 1- and 2-charged particles. The comparison of the ωn3-method with the traditional methods and with the method based on the ωn2-criterion shows that the new method outperforms the ωn2-method and most of the traditional ones in efficiency, but compares unfavourably with the likelihood method in power, however, the former has a number of advantages as compared with the latter. 相似文献
72.
73.
This paper examines Total Quality Management (TQM) as defined by Dr. W. Edwards Deming including Deming's fourteen points and explains how the United States' Department of Defense (DOD) defines TQM and why TQM is necessary. It also covers how the DOD is planning on implementing TQM and the policy that has been established as guidance in the implementation process. 相似文献
74.
A crack-tip screening analysis of cleavage fracture of steel is developed. The analysis incorporates evidence that reinitiation
of an arrested cleavage crack requires less stress intensity than cleavage initiation from a fatigue precrack. Fractographic
evidence as well as metallographic sectioning of arrested cracks have previously shown that the mechanism of rapid crack propagation
by cleavage is affected strongly by partial crack-plane deflection which leaves unbroken ligaments in its wake. The tearing
of these ligaments by dimple rupture is the dominant energy-absorbing mechanism. Earlier etch-pit experiments using an Fe-Si
alloy showed that the crack-tip stress intensity based on plastic zone size is extremely low. These observations are incorporated
into a model in which cleavage crack reinitiation is analyzed using a sharp crack that is shielded by a distribution of pinching
forces along its faces. During reloading of the arrested crack, the ligaments restrict crack-tip blunting, leading to higher
local stresses. As a result, lower stress intensities are needed for reinitiation than for initiation from a fatigue precrack. 相似文献
75.
Werner Baltes Gloria Bochmann 《Zeitschrift für Lebensmitteluntersuchung und -Forschung A》1987,184(3):179-186
Summary From model roastings of mixtures containing serine, threonine and sucrose about 350 volatile compounds were separated and identified by GC/MS. Among them there were more than 100 monocyclic furans, 13 furanones and 8 bicyclic furans, the mass spectra and retention indices of which are recorded. The most important mass spectrometric fragmentation pathways are described. Spectra obtained from roasting coffee under identical conditions are compared with the spectra from model roastings.
Dissertation Gloria Bochmann, TU Berlin 1984 相似文献
Modell-Reaktionen zur Röstaroma-BildungII. Die massenspektrometrische Identifizierung von Furanen und Furanonen aus der Reaktion von Serin und Threonin mit Saccharose unter den Bedingungen der Kaffeeröstung
Zusammenfassung Aus Modellröstungen von Gemischen aus Serin, Threonin und Saccharose unter den Bedingungen der Kaffeeröstung wurden etwa 350 flüchtige Verbindungen mittels GC/MS getrennt und identifiziert. Unter ihnen befanden sich über 100 monocyclische Furane und 13 Furanone sowie 8 bicyclische Furane, deren Massenspektren und Retentions-indices angegeben werden. Die wichtigsten massenspektrometrischen Fragmentierungswege werden beschrieben. -Die aus einer gleich behandelten Röstung von Rohkaffee erhaltenen Spektren werden mit denen der Modellröstungen verglichen.
Dissertation Gloria Bochmann, TU Berlin 1984 相似文献
76.
Nitrification is a key step for reliable biological nitrogen removal. In order to enhance nitrification in the activated sludge (AS) process, membrane-attached biofilm (MAB) was incorporated in a conventional activated sludge tank. Simultaneous organic carbon removal and nitrification of the MAB incorporated activated sludge (AS + MAB) process was investigated with continuous wastewater treatment. The effluent TOC concentration of AS and the AS + MAB processes were about 6.3 mg/L and 7.9 mg/L, respectively. The TOC removal efficiency of both AS and AS + MAB were above 95% during the wastewater treatment, indicating excellent organic carbon removal performance in both processes. Little nitrification occurred in the AS process. On the contrary, successful nitrification was obtained with the AS + MAB process with nitrification efficiency of about 90%. The volumetric and surface nitrification rates were about 0.14 g/Ld and 6.5 g/m2d, respectively. The results clearly demonstrated that nitrification in the conventional AS process was boosted by MAB. Furthermore, the microfaunal population in the AS + MAB process was different from that in the AS process. The high concentration of rotifers in the AS + MAB process was expected to decrease the generation of excess sludge in the process. 相似文献
77.
We consider the switchbox routing problem of two-terminal nets in the case when all thek nets lie on two adjacent sides of the rectangle. Our routing model is the standard two-layer model. We develop an optimal algorithm that routes all the nets whenever a routing exists. The routing obtained uses the fewest possible number of vias. A more general version of this problem (adjacent staircase) is also optimally solved.This research was supported in part by NSA Contract No. MDA-904-85H-0015, NSF Grant No. DCR-86-00378, and by NSF Engineering Research Centers Program NSFD CDR 88003012. 相似文献
78.
本文介绍了一个用户接口管理系统NUUIMS的设计和实现.重点叙述了该系统基于规范化目标用户接口模型的设计思想,系统组成及描述方法.文章也讨论了使用NUUIMS设计而成的用户接口的特点. 相似文献
79.
80.
The atomistic structure and energies of high-index interphase boundaries are explored using a combination of molecular statics
and dynamics simulations with embedded atom potentials. We investigate planar boundaries between the α2 and γ phases in the Ti−Al system. The class of boundaries considered has a high-index boundary orientation; the orientation
relationship between the α2 and γ phases also is high index, and a set of planes from each phase meet edge to edge at the boundary plane. For the particular
case of a boundary that is commensurate in one direction and coincides with a moiré plane given by the so-called “Δg” diffraction condition, the boundary is not structurally singular, but it is energetically stable and does not appear to
dissociate into other low-energy configurations. Misfit compensating defects are not observed; misfit in directions other
than the commensurate one appears to be distributed uniformly. The boundary energy is evaluated as a function of the orientation
of the boundary plane, and the edge-to-edge (moiré) boundary is found to lie in an energy cusp.
This article is based on a presentation made in the “Hume-Rothery Symposium on Structure and Diffusional Growth Mechanisms
of Irrational Interphase Boundaries,” which occurred during the TMS Winter meeting, March 15–17, 2004, in Charlotte, NC, under
the auspices of the TMS Alloy Phases Committee and the co-sponsorship of the TMS-ASM Phase Transformations Committee. 相似文献