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排序方式: 共有394条查询结果,搜索用时 15 毫秒
91.
Stephane Brugger 《中国建筑装饰装修》2012,(2):28-31
建筑师:Sid Lee建筑事务所+Aedifica项目地点:加拿大,魁北克建筑面积:789M.C.摄影:Stephane Brugger Architects:Sid Lee Architecture+Aedifica Location:Montreal,Quebec,Canada Gross Floor Area:789M.C.Photos:Stéphane Brügger 相似文献
92.
Odne S. Burheim Huaneng Su Sivakumar Pasupathi Jon G. Pharoah Bruno G. Pollet 《International Journal of Hydrogen Energy》2013
The thermal conductivity and the thickness change with pressure of several different micro porous layers (MPL) used for the polymer electrolyte membrane fuel cell (PEMFC) were measured. The MPL were made with different compositions of carbon and polytetrafluoroethylene (PTFE). A one-dimensional thermal PEMFC model was used to estimate the impact that the MPL has on the temperature profiles though the PEMFC. 相似文献
93.
Diameter-dependent electromechanical properties of GaN nanowires 总被引:1,自引:0,他引:1
The diameter-dependent Young's modulus, E, and quality factor, Q, of GaN nanowires were measured using electromechanical resonance analysis in a transmission electron microscope. E is close to the theoretical bulk value ( approximately 300 GPa) for a large diameter nanowire (d=84 nm) but is significantly smaller for smaller diameters. At room temperature, Q is as high as 2,800 for d=84 nm, significantly greater than what is obtained from micromachined Si resonators of comparable surface-to-volume ratio. This implies significant advantages of smooth-surfaced GaN nanowire resonators for nanoelectromechanical system (NEMS) applications. Two closely spaced resonances are observed and attributed to the low-symmetry triangular cross section of the nanowires. 相似文献
94.
Navarro JR Manchon D Lerouge F Cottancin E Lermé J Bonnet C Chaput F Mosset A Pellarin M Parola S 《Nanotechnology》2012,23(14):145707
A great number of works focus their interest on the study of gold nanoparticle plasmonic properties. Among those, sharp nanostructures appear to exhibit the more interesting features for further developments. In this paper, a complete study on bipyramidal-like gold nanostructures is presented. The nano-objects are prepared in high yield using an original method. This chemical process enables a precise control of the shape and the size of the particles. The specific photophysical properties of gold bipyramids in suspension are ripened by recording the plasmonic response of single and isolated objects. Resulting extinction spectra are precisely correlated to their geometrical structure by mean of electron tomography at the single-particle level. The interplay between the geometrical structure and the optical properties of twisted gold bipyramids is further discussed on the basis of numerical calculations. The influence of several parameters is explored such as the structural aspect ratio or the tip truncation. In the case of an incident excitation polarized along the particle long axis, this study shows how the plasmon resonance position can be sensitive to these parameters and how it can then be efficiently tuned on a large wavelength range. 相似文献
95.
William Hoareau Francielli B. Oliveira Stephane Grelier Bernard Siegmund Elisabete Frollini Alain Castellan 《大分子材料与工程》2006,291(7):829-839
Summary: Fiberboards were prepared using phenolic type resins (phenol‐formaldehyde) and sugarcane bagasse fibers. Lignin extracted through an organosolv process from sugarcane bagasse was used as substitute of phenol in phenolic resins from 40 (lignin‐phenol‐formaldehyde) to 100 wt.‐% (lignin‐formaldehyde) substitution. Some of the fibers were chemically modified by oxidation with chlorine dioxide and treatment with furfuryl alcohol (FA), leading to fibers coated with polyfurfuryl alcohol. Thermal analysis (DSC and TGA) of the prepolymers allowed setting up an efficient curing to prepare fiberboards. Impact strength and water absorption were measured showing the importance of the curing pressure to obtain good performance. When chemically modified fibers were used to prepare board samples, enhanced durability against white root fungi is observed, and to a less degree against brown root fungi. Sugarcane bagasse fiberboards were prepared from prepolymers where lignin substituted phenol up to 100%. This replaces these materials in advantageous position, relating to those prepared from phenol‐formaldehyde resins, due to their high content of renewable raw materials. The results obtained are promising for the utilization of sugarcane bagasse as raw materials for preparing fiberboards to be used in tropical areas.
96.
97.
Yu Wang Milca Aponte Neliza Leon Idalia Ramos Rogerio Furlan Nicholas Pinto Stephane Evoy Jorge J. Santiago-Avilés 《Journal of the American Ceramic Society》2005,88(8):2059-2063
Ultrafine tin oxide (SnO2 ) fibers having a rutile structure, with diameter ranging from 100 nm to several micrometers, were synthesized using electrospinning and metallorganic decomposition techniques. In this work, we propose a precursor solution that is a mixture of pure SnO2 sol made from SnCl4 :H2 O:C3 H7 OH:2-C3 H7 OH at a molar ratio of 1:9:9:6, and a viscous solution made from poly(ethylene oxide) (PEO) (molecular weight 900 000) and chloroform (CHCl3 ) at a ratio of 200 mg PEO/10 mL CHCl3 . This solution allows to obtain an appropriate viscosity for the electrospinning process. The as-deposited fibers were sintered at 400°, 500°, 600°, 700°, and 800°C in air for 2 h. Scanning electron microscopy, scanning probe microscopy, X-ray diffraction, Raman microspectrometry, and X-ray photoelectron spectroscopy (XPS) were used to characterize the sintered fibers and elucidate the chemical reaction during sintering. The results showed that up to the sintering temperature of 700°C, the synthesized fibers are composed of SnO2 . XPS was found to reflect the complicate chemical changes caused by the sintering process. 相似文献
98.
Stephane Girois 《乙烯基与添加剂工艺杂志》1999,5(4):218-230
The color requirements for vinyl siding have drastically evolved over the last decade and have moved toward medium to dark colors. Therefore, manufacturers are exploring new ways to modify their formulations in order to improve weather-ability of these challenging colors. Examination of some of the PVC additives typically used in these formulations has led to some interesting revelations about the performance of iron-containing pigments, which are extensively used in darker colors. A quick weathering test was designed to evaluate the effect of iron in PVC formulations, and this test clearly demonstrates the correlation between iron content and PVC photodegradation. 相似文献
99.
J.P. Doumerc M. Blangero M. Pollet D. Carlier J. Darriet R. Berthelot C. Delmas R. Decourt 《Journal of Electronic Materials》2009,38(7):1078-1082
The relevance of (bulk) transition-metal oxides for thermoelectric generation is discussed. A large power factor (i.e., a
large electronic conductivity coexisting with a large Seebeck coefficient) seems more easily achievable in either hopping-type
semiconductors or in highly correlated metallic systems such as layered cobaltites. 相似文献
100.
Bram DamenAnnick Pollet Emmie DornezWillem F. Broekaert Ingrid Van HaesendonckIsabel Trogh Filip ArnautJan A. Delcour Christophe M. Courtin 《Food chemistry》2012,131(1):111-118
Multiple studies have revealed the prebiotic activity of cereal derived arabinoxylan oligosaccharides (AXOS). This study investigated the in situ production of AXOS during bread making. In the first part, the AXOS producing capacity of different xylanases was compared in whole meal bread making. Three mesophilic xylanases originating from Bacillus subtilis, Aspergillus niger and Hypocrea jecorina, and one thermophilic xylanase from H. jecorina (HjXynA), were used in different dosages. At dosages that did not impair dough manageability, HjXynA solubilised and cleaved the arabinoxylan fraction to the largest extent, resulting in an AXOS content of 2.1% (dry basis) and an average degree of polymerisation (avDP) of 9. In the second part, the impact of HjXynA on the AXOS levels in dietary fibre enriched breads was studied. Rye or wheat bran fortified breads treated with HjXynA yielded good quality breads with AXOS levels above 2.0% with an avDP of 26 and 19, respectively. 相似文献