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1.
Thomsen Maria Carmignani Luca Rodriguez Andy Scudiere Charles Liveretou Christina Fernandez-Pello Carlos Gollner Michael Olson Sandra Ferkul Paul 《Fire Technology》2022,58(4):2229-2250
Fire Technology - There are multiple situations in which fires may occur at environmental conditions that are different than standard atmospheric conditions. Changes in ambient pressure, oxygen... 相似文献
2.
Geoffrey L. Beausoleil II Patrick Price David Thomsen Alex Punnoose Rick Ubic Scott Misture Darryl P. Butt 《Journal of the American Ceramic Society》2014,97(1):228-234
The thermal expansion and magnetic behaviors of divalent, alkaline‐doped lanthanum ferrites (La0.9M0.1FeO3, M=Ca, Sr, Ba) were assessed using a combination of dilatometry, magnetometry, time‐of‐flight neutron diffraction, and high‐temperature X‐ray diffraction. Néel temperatures were determined through vibrating sample magnetometry and correlated well with changes in thermal expansion behavior observed during both dilatometry and X‐ray diffraction. The Néel temperatures observed for pure, Ca‐doped, Sr‐doped, and Ba‐doped lanthanum ferrites were 471°C, 351°C, 465°C, and 466°C, respectively. The effect of divalent substitutions on the magnetic behavior are attributed to charge compensation mechanisms and structural changes in the material. 相似文献
3.
Urban Åkesson Jan Erik Lindqvist Björn Schouenborg Bent Grelk 《Bulletin of Engineering Geology and the Environment》2006,65(1):73-79
The use of thin (20–40 mm) marble as cladding for building facades has increased substantially during the last few decades. Many of the marble facades perform but some durability problems have occurred, especially with calcite marble, when the cladding starts to bow indicating a decrease in strength. This study considers the influence of the microstructure on the bowing of the calcite marble using adjacent grains analysis. Samples with a granoblastic texture all had six adjacent grains while those with a more complex microstructure had up to 13 adjacent grains. The samples with a granoblastic texture had the greatest degree of bowing, suggesting that the microstructure is a crucial parameter for the durability of marble and that adjacent grains analysis could be a fast and easy method to assess the suitability of marble for cladding purposes. 相似文献
4.
5.
L. Zanini S. Dementjev W. Leung K. Thomsen M. Wohlmuther A. Class P. Agostini J.-C. David S. Leray L. Cachon P. Roubin N. Thiolliere 《Journal of Nuclear Materials》2011,415(3):367-377
The (MEGAWatt Pilot Experiment) MEGAPIE target was successfully irradiated in 2006 at the SINQ facility of the Paul Scherrer Institut. During the irradiation a series of measurements to monitor the operation of the target, the thermal hydraulics behavior and the neutronic and nuclear aspects, has been performed. In the post-test analysis phase of the project, the data were analyzed and important information relevant to accelerator-driven systems (ADS) was gained, in particular: (i) from the operation of the target several recommendations concern the simplification of the system and the improved reliability; (ii) data from the thermal hydraulic measurements have offered the opportunity to validate the codes used in the design phase; (iii) the neutronic analysis confirm the high performance of a liquid metal target and the importance of the delayed neutron measurements in an ADS target; (iv) the nuclear measurements of the gas released gave the opportunity to validate the codes used during the design phase and provided indications for the operation. From the results in these different domains recommendations to further development of ADS and heavy liquid metal targets are discussed. 相似文献
6.
Bent Wiencke 《International Journal of Refrigeration》2011,34(8):2092-2108
Throughout the past decades, the industrial refrigeration industry has developed various “rule of thumb” methods for sizing gravity liquid separators for ammonia and other common refrigerants. However, to date a uniform systematic approach or an agreeable standard has not been established. For commonly used refrigerants such as ammonia, the large installed base of separators can be used as a benchmark for sizing separators. But, when using a less common refrigerant such as CO2, the designer faces new challenges. In this paper, a systematic approach is presented for sizing horizontal and vertical gravity liquid separators for industrial refrigeration applications. To compute separation velocities and separation distances, a theoretical model is presented. The model is used as a basis for comparison with observations from 85 operating gravity separators surveyed in the field. Criteria and formulas are presented for estimating the required liquid volume for storage. An example is provided demonstrating the use of the methods presented in this paper. 相似文献
7.
不同脱毒方法对玉米秸秆水解液酒精发酵的影响 总被引:2,自引:1,他引:1
利用湿热预处理(195℃,15 min)后的玉米秸秆水解液,考察了3种不同脱毒方法(中和法、饱和生石灰法和Na2SO3法)对水解液中的抑制剂的去除效果,研究了树干毕赤酵母(Pichia stipitis 58376)对脱毒后的水解液酒精发酵情况.结果表明:玉米秸秆水解液经过3种方法脱毒处理后,醛类抑制荆(糠醛和5-羟甲... 相似文献
8.
On the Relation between Morphology and FET Mobility of Poly(3‐alkylthiophene)s at the Polymer/SiO2 and Polymer/Air Interface 下载免费PDF全文
Wibren D. Oosterbaan Jean‐Christophe Bolsée Linjun Wang Veerle Vrindts Laurence J. Lutsen Vincent Lemaur David Beljonne Lars Thomsen Jean V. Manca Dirk J. M. Vanderzande 《Advanced functional materials》2014,24(14):1994-2004
The influence of the interface of the dielectric SiO2 on the performance of bottom‐contact, bottom‐gate poly(3‐alkylthiophene) (P3AT) field‐effect transistors (FETs) is investigated. In particular, the operation of transistors where the active polythiophene layer is directly spin‐coated from chlorobenzene (CB) onto the bare SiO2 dielectric is compared to those where the active layer is first spin‐coated then laminated via a wet transfer process such that the film/air interface of this film contacts the SiO2 surface. While an apparent alkyl side‐chain length dependent mobility is observed for films directly spin‐coated onto the SiO2 dielectric (with mobilities of ≈10?3 cm2 V?1 s?1 or less) for laminated films mobilities of 0.14 ± 0.03 cm2 V?1 s?1 independent of alkyl chain length are recorded. Surface‐sensitive near edge X‐ray absorption fine structure (NEXAFS) spectroscopy measurements indicate a strong out‐of‐plane orientation of the polymer backbone at the original air/film interface while much lower average tilt angles of the polymer backbone are observed at the SiO2/film interface. A comparison with NEXAFS on crystalline P3AT nanofibers, as well as molecular mechanics and electronic structure calculations on ideal P3AT crystals suggest a close to crystalline polymer organization at the P3AT/air interface of films from CB. These results emphasize the negative influence of wrongly oriented polymer on charge carrier mobility and highlight the potential of the polymer/air interface in achieving excellent “out‐of‐plane” orientation and high FET mobilities. 相似文献
9.
In the present paper the Natvig measures of component importance for repairable systems, and its extended version are analyzed for two three-component systems and a bridge system. The measures are also applied to an offshore oil and gas production system. According to the extended version of the Natvig measure a component is important if both by failing it strongly reduces the expected system uptime and by being repaired it strongly reduces the expected system downtime. The results include a study of how different distributions affect the ranking of the components. All numerical results are computed using discrete event simulation. In a companion paper [Huseby AB, Eide KA, Isaksen SL, Natvig B, Gåsemyr, J. Advanced discrete event simulation methods with application to importance measure estimation. 2009, submitted for publication] the advanced simulation methods needed in these calculations are described. 相似文献
10.
The free vibration analysis of sandwich panels with a core that is flexible and compliant in the vertical direction and with temperature-dependent mechanical properties is presented in two parts. The first part presents the mathematical formulation while the second deals numerically with the effects of the degrading properties of the core on the free vibration response. The analysis is based on the high-order sandwich panel theory approach (HSAPT), and the equations of motions along with the appropriate boundary conditions are derived using the Hamilton’s principle. The study investigates the role of increasing temperature, through the degradation of the mechanical properties of the core, on the free vibration response of structural sandwich panels. The mathematical formulation uses two types of computational models. At first, following the HSAPT approach, the unknowns include the displacements of the face sheets as well as the shear stress in the core. Secondly, it is assumed that the through-thickness distributions of the vertical and horizontal core displacements can be represented as polynomials, following the results of the HSAPT static case, and the effect of the variable mechanical properties are implemented directly. 相似文献