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11.
Benchmarking plug-load densities is essential to bypass arbitrary and/or incorrect inputs used in building energy analysis. As more building simulationists play a decision-making role for the design team, they tend to lean on building energy standards and guidelines for preliminary inputs such as plug-load densities. It is necessary for building energy standards and rating systems to implement plug-load density benchmarks to reward design teams in their efforts to reduce plug-load energy use. Using case study buildings, this paper establishes benchmark plug-load densities for K-12 schools under two new categories – classrooms with computers and classrooms without computers. Eighteen K-12 schools including 9 elementary, 2 middle, and 7 high schools are assessed for actual plug-load densities. For the same case study buildings, four existing approaches – NREL, COMNET, ASHRAE 90.1-1989, and Title-24 are evaluated for plug-load densities. Results show under- and over-estimation of plug-load densities over actual densities. The development of benchmark for K-12 schools will pave way for instituting targets for trimming plug-load densities in new and retrofit building projects.  相似文献   
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Imidazolium bromide-based ionic liquids bearing phosphonyl groups on the cationic part were synthesized and grafted on γ-alumina (γ-Al2O3) powders. These powders were prepared as companion samples of conventional mesoporous γ-alumina membranes, in order to favor a possible transfer of the results to supported membrane materials, which could be used for CO2 separation applications. Effective grafting was demonstrated using energy dispersive X-ray spectrometry (EDX), N2 adsorption measurements, fourier transform infrared spectroscopy (FTIR), and special attention was paid to 31P and 13C solid state nuclear magnetic resonance spectroscopy (NMR).  相似文献   
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Zeng EY  Chou CC  Yu C 《Analytical chemistry》2002,74(17):4513-4518
Despite the unprecedented popularity of separation chromatography, the measurement of coeluting isomeric chemicals remains an extremely difficult task. We developed an analytical scheme capable of measuring two coeluting isomers using a single chromatographic column and a gas chromatography/tandem mass spectrometry system. The protocol utilized two product ion fragments generated from a common parent ion associated with the isomers for quantitation. The utility of the analytical scheme was demonstrated with the measurements of several pairs of coeluting polychlorinated biphenyl (PCB) isomers in standard solutions and fish liver samples. Best results were given when a set of stringent constraints for the abundance ratio of the two product ion fragments was satisfied. Analyses of seven fish liver samples collected from nearshore San Diego, CA, indicated that the domain that had been previously reported to comprise PCB 153 and PCB 168 actually contained PCB 153 only. Although only a selected number of PCB congeners were examined, the results presented indicate that the analytical scheme has the potential to be used to determine the concentrations of all chromatographically coeluted isomers.  相似文献   
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Magnetic resonance imaging (MRI) has traditionally been used exclusively in a role for patient diagnosis. However, it is unlikely that this role is sufficient for its continued prominence in medical imaging. Instead, the more ambitious role in diagnosis and also therapy/intervention will occur as demand for minimally invasive procedures increases. Fortunately, with recent improvement in technical specifications and creative pulse sequence design, MRI systems can now provide high quality near-real-time images that facilitate a variety of image-guided procedures, many based around delivery via catheters. While X-ray opacity is not available as a means for detecting the progression of the catheter in MRI systems today, a variety of novel hardware devices have been designed and used for MRI catheter tracking. This report provides a brief review of some fundamental methods for catheter tracking in MRI.  相似文献   
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Outlines a psychological procedure aimed at improving the working relationship between a newly hired executive and the executive's reporting official. The "Executive Fit Rehearsal" (EFR) attempts to systematically engage the executive and reporting official in a dialogue designed to anticipate and overcome problems resulting from individual differences in personality, expectations, work styles, and communication patterns. The procedure supports consensus and mutual understanding. To assess the effectiveness of the procedure, evaluation forms were mailed to participants of 15 consecutive Executive Fit sessions. Ss' reactions to the EFR indicate that the process facilitated adjustment to the work setting and improved communications. Comments from subordinates were more uniformly positive, suggesting that the process may be most helpful for new employees. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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The use of YBa2Cu3O7-x and Tl2CaBa2Cu2O8 high-temperature superconducting thin films to fabricate frequency selective surfaces (FSS) at millimeter-wave frequencies (75-110 GHz) is discussed. An analytical/numerical model was applied, using a Floquet expansion and the method of moments, to analyze bandstop superconducting frequency selective surfaces. Experimental results were compared with the model, and showed agreement with resonant frequency prediction with an accuracy of better than 1%. The use of the superconducting frequency selective surfaces as quasi-optical millimeter-wave bandpass filters was also demonstrated  相似文献   
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The molecular weight of the mannans dissolved from isolated yeast cell walls by the action of snail gut juice is shown to be about two to three times as large as that of the more familiar type of mannan preparation which has been extracted in the presence of sodium hydroxide. Other types of large mannan molecules are associated with certain intracellular membranes. The availability of the former materials may facilitate the study of the chemistry of the alkali-labile bonds on which the integrity of the yeast cell wall depends.  相似文献   
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