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41.
Nicholas Traina Stephen Kerber Dimitrios C. Kyritsis Gavin P. Horn 《Fire Technology》2017,53(4):1611-1640
This paper describes experimental investigations of fire service ventilation and suppression practices in full-scale residential structures, including a one-story, 112 m2, 3 bedroom, 1 bathroom house with 8 total rooms and a two-story 297 m2, 4 bedroom, 2.5 bathroom house with 12 total rooms. The two-story house featured a modern open floor plan, two-story great room and open foyer. Seventeen experiments were conducted varying fire location, ventilation locations, the size of ventilation openings and suppression techniques. The experimental series was designed to examine the impact of several different tactics on tenability: door control, vertical ventilation size, and exterior suppression. The results of these experiments examine potential occupant and firefighter tenability and provide knowledge the fire service can use to examine their vertical ventilation and exterior suppression standard operating procedures and training content. It was observed that door control performed better at controlling the thermal exposure to occupants than did fully opening the door. Additionally, the impact of increased vertical ventilation area was minimal, and only slightly reduced the thermal exposure to occupants in a few non-fire rooms. In the two-story structure, the non-fire rooms on the second floor consistently had larger thermal fractional effective rate (FER) values (approximately 2.5× the thermal risk to oocupants) than did the non-fire rooms on the first floor. Water application was also shown to reduce the thermal risk to occupants 60 s after water application 1/3rd the original values on second floor rooms of the two-storry structure and by at least 1/5th of the original values on the first floor rooms of both structures. Data also showed that the impact of front door ventilation on the toxic gases exposure was minimal, as the toxic gases FER actually increased after front door ventilation for several experiments. However, after vertical ventilation there was a 30% reduction in the toxic gases exposure rate in two of the one-story structure experiments. 相似文献
42.
Gavin Sutton Robin Underwood Laurent Pitre Michael de Podesta Staf Valkiers 《International Journal of Thermophysics》2010,31(7):1310-1346
We report on two sets of isothermal acoustic measurements made with argon close to the triple point of water using a 50 mm
radius, thin-walled, diamond-turned quasisphere. Our two isotherms yielded values for the Boltzmann constant, k
B, which differ by 0.9 parts in 106, and have an average value of k
B = (1.380 649 6 ± 0.000 004 3) × 10−23J · K−1. The relative uncertainty is 3.1 parts in 106, and the average value is 0.58 parts in 106 below the 2006 CODATA value (Mohr et al. Rev Mod Phys 80:633, 2008), and so the values are consistent within their combined
(k = 1) uncertainties. 相似文献
43.
Gavin S. Walker David M. Grant Tobias C. Price Xuebin Yu Vincent Legrand 《Journal of power sources》2009,194(2):1128-1134
LiBH4–MgH2 is an attractive reversible hydrogen storage system, it combines two high capacity hydrides (18.3 and 7.6 wt.%, respectively) and the concerted dehydrogenation reaction has a smaller enthalpy change than either species on its own. The latter effect leads to a destabilisation of the hydrided products and results in a lowering of the dehydrogenation temperature. In situ neutron diffraction experiments have been undertaken to characterise the mechanism of decomposition of the LiBD4–MgD2 system, with an emphasis on investigating the synergistic effects of the components during cycling under various conditions. This study compares the effect of stoichiometry of the multicomponent system on the cycling mechanism. Results show that LiBD4–MgD2 in a 2:1 molar ratio can be reversibly dehydrogenated under low pressures of hydrogen or under vacuum, contrary to earlier reports in the literature, although the reaction was only partially reversed for the 2:1 mixture decomposed under vacuum. This work shows that the reaction pathway was affected by dehydrogenation conditions, but the stoichiometry of the multicomponent system played a minor role. 相似文献
44.
Reference lists appended to published journals are of critical importance to readers of academic literature. They allow readers to retrieve cited sources, either to increase their own knowledge or to substantiate the authors' claims, and in so doing help to establish the judgment and credibility of the authors (M. F. McLellan et al, 1992). However, erroneous references detract from the intended function of reference lists by impeding retrieval searches and by providing misleading bibliographic information (G. de Lacey et al, 1985; McLellan et al, 1992). The present study aims to assess the accuracy of reference lists in five experimental psychology journals published by the American Psychological Association (APA) in 1999 (Journal of Experimental Psychology: Animal Behavior Processes, Journal of Experimental Psychology: Applied, Journal of Experimental Psychology: Learning, Memory, and Cognition, Journal of Experimental Psychology: Human Perception and Performance, and Journal of Experimental Psychology: General). Perhaps the most disturbing result from this study is the finding that authors were incorrectly cited in 12% of reference list citations, with errors in the initials of the authors being the most common. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
45.
Base Resistance of Jacked Pipe Piles in Sand 总被引:1,自引:0,他引:1
The paper presents the results from an experimental program carried out at Trinity College Dublin, in which instrumented model piles were jacked into loose dry sand in a large testing chamber. A number of pile installations were carried out to study the effects of in situ stress, diameter, and wall thickness on the behavior of open-ended piles in sand. These indicated that plug stiffness and capacity may be expressed as simple functions of the cone penetration test end resistance and the incremental filling ratio prior to loading. The magnitude and distribution of shear stresses measured on the inner wall are shown to be compatible with existing experimental data and can be related directly to the stress level, interface friction angle, and dilation of the sand at the pile wall. The data are shown to facilitate a better understanding of the factors controlling plug resistance. 相似文献
46.
A.P. Rijpma H.J.G. Krooshoop M.W. Lefevere E.P. van Leeuwen H.J. Holland B. ten Haken H.J.M. ter Brake 《低温学》2008,48(1-2):61-67
A cryocooler-cooled low-Tc SQUID gradiometer system was designed and constructed. It is based on a 4 K GM-cooler that is positioned several meters from the measuring head containing the SQUID sensors. The cooling power is transported by means of a circulating helium flow. Thus, there are three main components: the cooler vessel, the measuring head and the connecting flow-line.In stable operation, the SQUID and gradiometric pick-up loop are about 4.3 K. The overall heat loads to the cooler 1st and 2nd stages are estimated at 17 W and 0.3 W, respectively. The overall system noise was about 10 fT/√Hz although a number of peaks were observed in the spectrum. As an example, an adult heart beat was recorded. 相似文献
47.
Gavin Lawes Simon C. J. Kingsley Andrei Golov Norbert Mulders James V. Porto Jeevak M. Parpia 《Journal of Low Temperature Physics》2000,121(5-6):567-572
We have investigated the superfluid transition of
3
He in different samples of silica aerogel. Several of these samples have been characterized using x-ray imaging, yielding information about the microstructure of the aerogel. In comparing new measurements on a 99.5% sample with previous observations on the behavior of
3
He in 98% porous aerogel we have found evidence for a scaling of the superfluid transition temperature to the correlation length of the aerogel. Furthermore, the superfluid density exhibits a similar universal behaviour over a range of values of reduced temperature. We discuss these new results in the context of superfluid pairing in the presence of a correlated disorder, specifically focussing on the fractal nature of the aerogel. 相似文献
48.
The influence of CS-US interval on several different indices of learning in appetitive conditioning.
Four experiments examined the effects of varying the conditioned stimulus-unconditioned stimulus (CS-US) interval (and US density) on learning in an appetitive magazine approach task with rats. Learning was assessed with conditioned response (CR) measures, as well as measures of sensory-specific stimulus-outcome associations (Pavlovian-instrumental transfer, potentiated feeding, and US devaluation). The results from these studies indicate that there exists an inverse relation between CS-US interval and magazine approach CRs, but that sensory-specific stimulus-outcome associations are established over a wide range of relatively long, but not short, CS-US intervals. These data suggest that simple CR measures provide different information about what is learned than measures of the specific stimulus-outcome association, and that time is a more critical variable for the former than latter component of learning. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
49.
An experimental study has been carried out on a continuously operated pilot fractional distillation column equipped with an external heat pump. The distillation column was a 15 cm internal diameter glass unit containing eleven single bubble cap plates. A methanol-water mixture was fed to the column. After operating the heat pumps with R114 as the working fluid, further experiments have been conducted with R11 as the working fluid. Plots of pressure against enthalpy, condensation pressure and latent heat of vaporization against condensation temperature and theoretical Rankine coefficient of performance against gross temperature lift and condensation temperature are presented for both R114 and R11. R11 has correspondingly higher theoretical Rankine coefficients of performance than R114. The experiments show that the actual coefficients are also higher for R11 than for R114. A maximum actual coefficient of performance of 5.3 was obtained using R11 as the working fluid with a gross temperature lift of 38.4°C. The experimental data for R11 were found to be reproducible during operation over a number of weeks. This showed that the relative thermal instability of R11 compared to R114 had not apparently affected the performance of the system. 相似文献
50.
Christensen Helen; Hadzi-Pavlovic Dusan; Andrews Gavin; Mattick Richard 《Canadian Metallurgical Quarterly》1987,55(5):701
A meta-analysis was used to integrate the research literature on the treatment of obsessive-compulsive disorder. Antidepressants, such as clomipramine, and behavior therapy have produced appreciable changes in obsessive-compulsive and depressive symptoms. Patients with obsessions who did not suffer from compulsions have responded less to treatment. No follow-up data have been available for clomipramine, but the benefits of behavior therapy have been shown to be stable at follow-up. Ratings of improvement by assessors have been higher than ratings made by patients. The effects of tricyclic medication and exposure therapies have not significantly differed, but both have proven significantly superior to nonspecific treatment programs. There is a need for a large, randomized comparison of clomipramine and exposure that includes adequate follow-up of subjects after treatment has concluded. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献