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991.
Frank O Smith 《软件》2009,(9):18-21,23
实时控制不仅仅停留在工厂层面,而是开始介入企业管理层面,使管理能够获得更大的竞争优势。虽然只有少数企业采用这种方案,但是这些企业无不具备了前所未有的办事能力。 相似文献
992.
In this work we quantify and characterise the effects of air-oxidation on nitrogen-vacancy defect luminescence in both high-temperature-high-pressure and detonation synthesized nanodiamonds using Raman and luminescence spectroscopies. We find that oxidation treatments result in an increased nitrogen-vacancy centre excited state lifetime from 13 ns to 25 ns and in 5-nm diamonds the intensity of this luminescence increases by at least 5-fold. At the same time, in 5-nm diamonds, short lived surface-defect related luminescence is reduced by 10-fold. Furthermore we find that air oxidation reduces the sp2 and disordered carbon fraction of nanodiamonds by up to 5-fold in 5-nm nanodiamonds. Based on these results, the authors suggest that the disordered-carbon and graphite shell of 5-nm nanodiamonds quenches nitrogen-vacancy luminescence, and that this quenching can be partially reduced by surface oxidation. These findings provide useful insights into the role of the graphite and disordered carbon shell in quenching luminescence, and have implications for the applicability of 5-nm nanodiamonds to bio- and quantum physics applications. 相似文献
993.
This study investigates the relationship between depression and labor force participation by examining whether retirement induces depression or depression discourages labor force participation. The sample is drawn from newly available, nationally representative data of those 50–64 years old using the 2006 Korean Longitudinal Study of Aging. We model two possibly inter-related outcomes; depression and work. We first examine whether retirement influences depression, using the mandatory retirement provisions of the Korean labor force to identify a pathway to retirement that is not a consequence of depression. We then estimate the determinants of current work using instrumental variables for depression. We find that mandatory retirement is not associated with subsequent depression but find evidence that depression leads to reduced labor force participation, after using instrumental variables to predict the existence of depressive symptoms among respondents. We find strong evidence that depression leads to reduced labor force participation. Although retirees are often more depressed than workers, the causes that induce retirement, such as poor health, care-giving responsibilities, and inability to find a job, are also associated with depression. 相似文献
994.
Diffraction grating scanners using polysilicon micromotors 总被引:1,自引:0,他引:1
Azzam Yasseen A. Smith S.W. Merat F.L. Mehregany M. 《IEEE journal of selected topics in quantum electronics》1999,5(1):75-82
This paper describes polysilicon micromotors with single and pyramidal diffraction grating elements fabricated on the polished surface of large-area rotors for optical scanning applications. While taking full advantage of planar processing, such scanners have high-quality scan profiles, good efficiency, meter working distances, and multiple out of plane beam diffraction orders. Chemical-mechanical polishing was used to reduce the 5-μm-thick polysilicon rotors' average surface roughness from 420 Å to below 17 Å, with less than 1500-Å film removal, improving the optical performance of the gratings as well as the definition, delineation, and side wall quality of the device features. Self-assembled monolayers (SAM) were found to improve the overall micromotor's dynamic performance. SAM-coated scanners could operate at voltages as low as 15 V and maximum operational speeds of 5200 rpm. The gratings were tested optically at 633-nm wavelength and were verified to have spatial periods of 1.80 and 3.86 μm, closely matching their design values. Stepping and continuous mode dynamic operation of the scanners was demonstrated with visible diffraction orders at meter distances away 相似文献
995.
The nature of the initial carbides formed during the early stages of the tempering of steels is still a matter of debate. Conventionally, the main transition carbide is described as epsilon carbide, with a composition of approximately Fe2.4C. However, earlier one-dimensional atom probe (1DAP) results indicated the existence of carbon-rich regions having much lower carbon contents, with maxima of around 10 at%. There was some uncertainty about the interpretation of the 1DAP results, because of possible problems with alignment of the aperture and with trajectory aberration effects. We have therefore re-visited this topic, using the three-dimensional (3D) atom probe, and studying both a model Fe–Ni–C alloy and a well-known engineering steel (AISI4340). We demonstrate that, for both materials, low-temperature (20–150 °C) aging produces carbon-rich regions with average peak carbon contents of up to 10%. We show for the first time the three-dimensional structure of these carbon-rich regions, and demonstrate that fine-scale faulting exists within them. 相似文献
996.
Carolyn V. Coulter Robin A. J. Smith Michael P. Murphy 《Fullerenes, Nanotubes and Carbon Nanostructures》2001,9(3):339-350
A monofunctionalised fullerene triphenylphosphonium salt has been synthesised to investigate the potential for adaptation of fullerenes for biological application. The redox properties of fullerenes make them effective radical scavengers and consequently they are potential antioxidants in biological systems The triphenylphosphonium moiety was chosen because this lipophilic cation increases both the solubility and membrane permeability of attached compounds, and has been used as a delivery agent in biological systems in other contexts. Furthermore, the triphenylphosphonium moiety binds tightly to cognate antibodies, facilitating linkage of attached molecules to proteins. Here we report on the interaction of a triphenylphosphonium fullerene salt with biological systems and its binding of antibodies against the triphenylphosponium moiety. 相似文献
997.
The purpose of this study was to test a 2-factor model of affective health in women with rheumatoid arthritis (RA; n = 82) or osteoarthritis (OA; n = 88). Positive and negative social interactions and affect were assessed for 11 consecutive weeks. For each participant, Vulnerability and Resilience factors were created from factor analyses of positive and negative personal characteristics, respectively. Multilevel analyses tested the hypothesis that weekly changes in social interactions or affect would only be predicted by the factor of the same valence. The Vulnerability (and not the Resilience) factor predicted changes in negative interactions. The Resilience (and not the Vulnerability) factor predicted changes in positive interactions. The Vulnerability (and not the Resilience) factor predicted changes in current and next-week negative affect. The Resilience and Vulnerability factors each predicted changes in current and next-week positive affect, although the effects for Vulnerability were smaller than for Resilience. Finally, the Vulnerability factor interacted with pain to predict more future negative affect. The main implication is that both Vulnerability and Resilience should be considered in theory, research, and interventions. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
998.
R.Kent Boevers Michael Branson Ph.D. Chester Sidney Smith Jr. 《Computers & Industrial Engineering》1987,13(1-4):416-418
With the advent of DRG reimbursement for Medicare patients, hospitals have had to use their case mix data more effectively. This paper describes a method use to develop summary case mix reports using a spreadsheet program. With this approach, the hospital administration could interact more during the development of the summary reports. Once the summary reports are stabilized, they can be put into production on the Hospital's main frame computer. 相似文献
999.
M. L. Wayman R. R. Smith M. G. Wright 《Metallurgical and Materials Transactions A》1986,17(3):429-434
The diffusion bonding of zirconium-2.5 pct niobium to carbon steel with an interlayer of platinum has been investigated. Bonds
were produced by heating samples in a furnace under compressive loading. Metallography of the bonds revealed that at both
the Fe-Pt and the Pt-Zr/Nb interfaces, interdiffusion and the formation of thin bands of intermetallic phases occurred during
bonding. The presence of FePt3 was detected at the former interface and several intermetallics including Pt3Zr at the latter. In both cases, intermetallic compound formation resulted in an increase in microhardness in the bond region;
this was particularly severe at the Pt-Zr/Nb interface where cracking was observed to occur during, metallographic sample
preparation. Bonding at temperatures above 1150 °C caused eutectic melting at the Pt-Zr/Nb interface. 相似文献
1000.
R Gomez L Dauwe H Haggerty E Malamud M Nikolic S Hagopian A Pifer R Abrams J Ares H Goldberg C Halliwell S Margulies D McLeod A Salminen J Solomon G Wu S Blessing R Crittenden P Draper A Dzierba R Heinz J Krider T Marshall J Martin A Sambamurti P Smith A Snyder C Stewart T Sulanke A Zieminski R Ellsworth J Goodman S Gupta G Yodh T Watts V Abramov Y Antipov B Baldin S Denisov V Glebov Y Gorin V Kryshkin A Petrukhin S Polovnikov R Sulyaev 《Canadian Metallurgical Quarterly》1987,35(9):2736-2746