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排序方式: 共有300条查询结果,搜索用时 15 毫秒
31.
Olivia Guerra Santin 《Energy and Buildings》2011,43(10):2662-2672
The difference between the actual and predicted energy consumption for heating in housing is thought to be partly attributable to the use of HVAC systems. More reliable data on energy consumption could help in determining the actual energy performance of dwellings and in the search for the most adequate design for housing and home amenities. Further reductions on energy consumption might also be achieved if energy-saving policy programmes were geared to different household groups. The aim of this paper is to statistically determine Behavioural Patterns associated with the energy spent on heating and to identify household and building characteristics that could contribute to the development of energy-User Profiles. This study had two outcomes: it identified Behavioural Patterns to be used in energy calculations and it discerned User Profiles with different behaviours. Five underlying groups of behavioural variables were found, which were used to define the Behavioural Patterns and User Profiles. The groups showed statistically significant differences in the scores for most of the behavioural factors. This study established clear relationships between occupant behaviour and household characteristics. However, it seems difficult to establish relationships between energy consumption and Behavioural Patterns and household groups. 相似文献
32.
Using coimmunoprecipitation and glutathione S-transferase pulldown experiments, we found that polyomavirus large T antigen binds to p300 in vivo and in vitro. The N-terminal region of the viral protein, including the pRB binding motif, was dispensable for this interaction, which involved several regions within the C-terminal half of the large T antigen. Interestingly, anti-T antibody coimmunoprecipitated a subspecies of p300 which has high histone acetyltransferase activity. 相似文献
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Rheological behavior and spinnability of biodegradable materials based on SPI and PVA were studied for the production of electrospun fibers. pH level, processing temperature, and heating time were adjusted to investigate the effects of denaturing of soy protein on the rheology of SPI/PVA solutions. The results show that zero shear viscosity and degree of shear thinning of the SPI solution can be controlled by adjusting pH level and thermal treatment. The continuous production of uniform SPI/PVA fibers was achieved by electrospinning. The presence and amount of soy protein in the electrospun fibers was determined by EMPA and elemental analysis, confirming that the SPI was well incorporated into the PVA and remained in the electrospun fibers.
36.
Yun Ma Yun‐Ling Jia Yan‐Li Shang Fu‐Hui Liao Jun‐Ran Li Shao‐Hua Zhang Olivia Zhang 《应用聚合物科学杂志》2007,105(4):2427-2432
Novel electrorheological materials based on crosslinked chitosan doped with Y2(CO3)3 were synthesized with biocompatible chitosan as the substrate of the materials. The electrorheological performance, surface energy, and thermal decomposition behavior of the materials were investigated as functions of the composition change. The results show that doping Y2(CO3)3 can improve effectively the electrorheological performance of crosslinked chitosan with the formation of a metal–polymer complex when the doping degree is suitable. The surface energy plays an important role in influencing the electrorheological properties of the material. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2007 相似文献
37.
García-Suárez O Pérez-Pérez M Germanà A Esteban I Germanà G 《Microscopy research and technique》2003,62(6):514-523
The thymus undergoes an age-dependent degenerative process which is mainly characterized by a progressive loss of lymphoid tissue. Thymic involution is particularly important in relation to immunosenescence and its various associated diseases; this fact has prompted many studies aimed at understanding the causes and mechanisms of thymic degeneration which may, ultimately, lead to the possibility of manipulating it. In this sense, one of the aspects which has deserved most attention is the thymic microenvironment, and more precisely, the many growth factors to which the cells present in the organ are exposed. Thus, the levels of several of such factors have been reported to undergo age-dependent changes in the thymus, which may point at an influence on the regression of the organ. In this article we consider which growth factors and growth factor receptors occur in the vertebrate thymus. Then, focusing on those whose influences are better documented, i.e., neurotrophins, cytokines and IGFs, we discuss their potential role in the organ and the possibility of their being involved in thymic involution. 相似文献
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Zachary Finewax Demetrios Pagonis Megan S. Claflin Anne V. Handschy Wyatt L. Brown Olivia Jenks Benjamin A. Nault Douglas A. Day Brian M. Lerner Jose L. Jimenez Paul J. Ziemann Joost A. de Gouw 《Indoor air》2021,31(5):1323-1339
Humans spend approximately 90% of their time indoors, impacting their own air quality through occupancy and activities. Human VOC emissions indoors from exercise are still relatively uncertain, and questions remain about emissions from chlorine-based cleaners. To investigate these and other issues, the ATHLETic center study of Indoor Chemistry (ATHLETIC) campaign was conducted in the weight room of the Dal Ward Athletic Center at the University of Colorado Boulder. Using a Vocus Proton-Transfer-Reaction Time-of-Flight Mass Spectrometer (Vocus PTR-TOF), an Aerodyne Gas Chromatograph (GC), an Iodide-Chemical Ionization Time-of-Flight Mass Spectrometer (I-CIMS), and Picarro cavity ringdown spectrometers, we alternated measurements between the weight room and supply air, allowing for determination of VOC, NH3, H2O, and CO2 emission rates per person (emission factors). Human-derived emission factors were higher than previous studies of measuring indoor air quality in rooms with individuals at rest and correlated with increased CO2 emission factors. Emission factors from personal care products (PCPs) were consistent with previous studies and typically decreased throughout the day. In addition, N-chloraldimines were observed in the gas phase after the exercise equipment was cleaned with a dichlor solution. The chloraldimines likely originated from reactions of free amino acids with HOCl on gym surfaces. 相似文献
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Eva Olivia Leontien Lantsoght Rutger T. Koekkoek Dick Hordijk Ane de Boer 《Structure and Infrastructure Engineering》2018,14(3):365-380
Proof load tests of bridges can be very useful for structures with a lack of information, or for structures of which the effect of material degradation is difficult to assess. Contrary to diagnostic load testing, proof load testing is not well-defined in current standards in terms of required load and analysis of measurements. The risk related to the high loads used in proof load testing requires standardisation for these tests. The paper highlights important considerations for proof load testing that may lead to the development of guidelines in the Netherlands, by illustrating a pilot study on the viaduct Zijlweg in the Netherlands. This reinforced concrete bridge rates too low in shear. Topics of interest are the required load that the bridge has to withstand to be approved by the load test and the interpretation of the measurements during the test to avoid permanent damage to the structure. These measurements were compared to the stop criteria from existing codes for buildings, to examine if recommendations for the use with bridges can be formulated. The final result of the test on this case study is that the capacity of the viaduct is proven to be sufficient for shear and bending moment. 相似文献