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141.
Petar Blanusa William P. Goss Hartwig Roth Peter Weitzmannn Claus F. Jensen Svend Svendsen Hakim Elmahdy 《Energy and Buildings》2007
The intent of this paper is to describe and compare the two different two-dimensional frame/spacer heat transfer calculation methodologies used in North America (FRAME [EEL. The FRAMEplus Toolkit for Heat Transfer Assessment of Building Components, Version 3.0, Enermodal Engineering, Kichener, Ontario, Canada, 1995], THERM [LBNL. THERM 2: PC Program for Analyzing Two-Dimensional Heat Transfer Through Building Products, LBL-37371, Windows and Delighting Group, Lawrence Berkeley National Laboratory, Berkeley, CA, 1998], ASHRAE SPC 142P [ASHRAE. Standard Method for Determining and Expressing the Heat Transfer and Total Optical Properties of Fenestration Products, Public Review Draft of Standard 142P, American Society of Heating, Refrigerating and Air Conditioning Engineers, Atlanta, 1998]) and in Europe [ISO 10077-2. Thermal Performance of Windows, Doors and Shutters–Calculation of Thermal Transmittance—Part 2: Numerical Method for Frames, International Standards Organization, Geneva, 2003]. The two approaches, called the ASHRAE and ISO methods, are different in the way they treat the effect of the glazing spacer on the heat transfer through the frame and the glazing unit near the frame. The ASHRAE method assumes that the spacer effects both the heat transfer through the frame and the heat transfer through the glazing in an “edge-of glass” region 63.5 mm (2.5 in.) from the glazing/frame sight line. The ISO method assumes that the additional heat transfer due to the existence of the spacer is proportional to the glazing/frame sightline distance that is also proportional to the total glazing spacer length. 相似文献
142.
Miroslav Krsti Petar V. Kokotovi
Ioannis Kanellakopoulos 《Systems & Control Letters》1993,21(6):451-461
Computable
performance bounds are derived in addition to global stability and asymptotic tracking, a systematic improvement of transient performance can be achieved. The underlying linear nonadaptive controller is shown to possess a parametric robustness property, but for a large parameter uncertainty it requires high gain. A comparison between the adaptive and the nonadaptive performance bounds demonstrates that adaptation improves the overall performance without the undesirable effects of high gain. 相似文献
143.
Vanesa Sanz Ewa Borowiak Petar Lukanov Anna Marie Galibert Emmanuel Flahaut Helen M. Coley S. Ravi P. Silva Johnjoe McFadden 《Carbon》2011,(5):1775-1781
The use of carbon nanotubes as a gene delivery system has been extensively studied in recent years owing to its potential advantages over viral vectors. To achieve this goal, carbon nanotubes have to be functionalized to become compatible with aqueous media and to bind the genetic material. To establish the best conditions for plasmid DNA binding, we compare the dispersion properties of single-, double- and multi-walled carbon nanotubes (SWCNTs, DWCNTs and MWCNTs, respectively) functionalized with a variety of surfactants by non-covalent attachment. The DNA binding properties of the functionalized carbon nanotubes were studied and compared by electrophoresis. Furthermore, a bilayer functionalization method for DNA binding on SWCNTs was developed that utilized RNA-wrapping to solubilize the nanotubes and cationic polymers as a bridge between nanotubes and DNA. 相似文献
144.
Petar Djinovi?Ilja Gasan Osojnik ?rnivec Jurka BatistaJanez Levec Albin Pintar 《Chemical Engineering and Processing: Process Intensification》2011,50(10):1054-1062
In this work, 3% Ru-Al2O3 and 2% Rh-CeO2 catalysts were synthesized and tested for CH4-CO2 reforming activity using either CO2-rich or CO2-lean model biogas feed. Low carbon deposition was observed on both catalysts, which negligibly influenced catalytic activity. Catalyst deactivation during temperature programmed reaction was observed only with Ru-Al2O3, which was caused by metallic cluster sintering. Both catalysts exhibited good stability during the 70 h exposure to undiluted equimolar CH4/CO2 gas stream at 750 °C. By varying residence time in the reactor during CH4-CO2 reforming, very similar quantities of H2 were consumed for water formation. Reverse water-gas shift (RWGS) reaction occurred to a very similar extent either with low or high WHSV values over both catalysts, revealing that product gas mixture contained near RWGS equilibrium composition, confirming the dominance of WGS reaction and showing that shortening the contact time would actually decrease the H2/CO ratio in the syngas produced by CH4-CO2 reforming, as long as RWGS is quasi equilibrated. H2/CO molar ratio in the produced syngas can be increased either by operating at higher temperatures, or by using a feed stream with CH4/CO2 ratio well above 1. 相似文献
145.
Nevena Ž. Prlainović Dejan I. Bezbradica Zorica D. Knežević-Jugović Sanja I. Stevanović Milka L. Avramov Ivić Petar S. Uskoković Dušan Ž. Mijin 《Journal of Industrial and Engineering Chemistry》2013,19(1):279-285
In this work lipase from Candida rugosa was adsorbed on unmodified surface of multi walled carbon nanotubes (raw-MWCNT). The effects of immobilization time, initial enzyme concentration and buffer ionic strength on enzyme loading and activity of immobilized preparations were tested. High loadings are attained. The immobilized enzyme obtained at lowest initial enzyme concentration and high ionic strength retained 85% of initial enzyme activity. It is assumed that immobilization on hydrophobic surface led to conformational changes that resulted in the adsorption of lipase in active conformation. Immobilized preparations were characterized, with FT-IR spectroscopy, AFM, and cyclic voltammetry. 相似文献
146.
Chuyen T. Nguyen Kazunori Hayashi Megumi Kaneko Petar Popovski Hideaki Sakai 《Wireless Personal Communications》2013,71(4):2947-2963
In this paper, we study radio frequency identification tag identification problems using framed slotted ALOHA protocol. Each tag will be assumed to participate in the contention with a certain probability. Then, the frame size and the probability will be dynamically controlled by the reader in every reading round so that all the tags can be detected in a short period of time. Moreover, we propose a practical way of controlling the probability in terms of transmit power control, assuming Additive White Gaussian Noise channel or flat Rayleigh fading channel. Computer simulation results demonstrate the effectiveness of the proposed method. 相似文献
147.
Clean Technologies and Environmental Policy - 相似文献
148.
Clean Technologies and Environmental Policy - 相似文献
149.
150.
Clean Technologies and Environmental Policy - 相似文献