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991.
992.
993.
Badri Rangarajan Tom Shrout Michael Lanagan 《Journal of the American Ceramic Society》2009,92(11):2642-2647
Nucleation and crystallization kinetics of fresnoite (Ba2 TiSi2 O8 ) crystals in BaO–TiO2 –SiO2 glasses have been explored for dielectric applications. The volume fractions crystallized at different temperatures and times were tracked by XRD analysis. The activation energy of crystallization was estimated from DTA results to be about 528 kJ/mol, which is consistent with the value obtained by XRD results. The Avrami parameter values calculated at different temperatures from DTA results were found to be between 3.2 and 3.9, indicating that the growth is three dimensional and the mechanism of growth is interface-controlled. Additionally, because of compositional similarities, the dielectric contrast between the glass (ɛr ∼15) and the resulting glass–ceramic (ɛr ∼18) was minimal. 相似文献
994.
Tom Adams 《Sealing Technology》2001,2001(89):7-10
It is important to be able to check the quality of seal, and this article looks at the use of acoustic micro imaging to inspect the bonding of a film t 相似文献
995.
Ben van Berkel Astrid Piber Ger Gijzen Marc Herschel Marianthi Tatari Sander Versluis Jorg Lonkwitz Tom Minderhoud Constantin Boincean Amsterdam 《城市环境设计》2010,(1):64-69
该大楼有20层,包含55个公寓,在楼中可以眺望啥德逊河、东河和曼哈顿的天际线。
该大楼有一个戏剧性、极富装饰性的立面,灵感来自Tribeca的19世纪的铸铁建筑和当代时尚。闪闪发光的黑色金属横带将包装的墙面扭曲,划分了阳台、平台和遮阳篷的位置,同时体现了立面的框架感。 相似文献
996.
Kendrick RL Aubrun JN Bell R Benson R Benson L Brace D Breakwell J Burriesci L Byler E Camp J Cross G Cuneo P Dean P Digumerthi R Duncan A Farley J Green A Hamilton HH Herman B Lauraitis K de Leon E Lorell K Martin R Matosian K Muench T Ni M Palmer A Roseman D Russell S Schweiger P Sigler R Smith J Stone R Stubbs D Swietek G Thatcher J Tischhauser C Wong H Zarifis V Gleichman K Paxman R 《Applied optics》2006,45(18):4235-4240
A nine-aperture, wide-field Fizeau imaging telescope has been built at the Lockheed-Martin Advanced Technology Center. The telescope consists of nine, 125 mm diameter collector telescopes coherently phased and combined to form a diffraction-limited image with a resolution that is consistent with the 610 mm diameter of the telescope. The phased field of view of the array is 1 murad. The measured rms wavefront error is 0.08 waves rms at 635 nm. The telescope is actively controlled to correct for tilt and phasing errors. The control sensing technique is the method known as phase diversity, which extracts wavefront information from a pair of focused and defocused images. The optical design of the telescope and typical performance results are described. 相似文献
997.
The equipment and methods used to produce wide-angle antireflection coatings based on Reststrahlen materials are described. The optical constants of the coating materials used in the construction of the multilayers were determined by spectrophotometric ellipsometry and are compared with the literature values. The measured performance of an experimentally produced antireflection coating is compared with the expected calculated performance. The reflectance is low over a wide range of angles, but only in the narrow-wavelength region at which the refractive index of the Reststrahlen material is close to unity. 相似文献
998.
Eijt SW van Veen AT Schut H Mijnarends PE Denison AB Barbiellini B Bansil A 《Nature materials》2006,5(1):23-26
Nanosized inorganic particles are of great interest because their electronic properties can be easily tailored, providing a tremendous potential for applications in optoelectronic devices, light-emitting diodes, solar cells and hydrogen storage. Confinement of electrons and holes to dimensions comparable to their wavelength leads to quantum-well states with modified wavefunctions and density of states. Surface phenomena are crucial in determining nanoparticle properties in view of their large surface-to-volume ratio. Despite a wealth of information, many fundamental questions about the nature of the surface and its relationship with the electronic structure remain unsolved. Ab initio calculations on CdSe nanocrystals suggest that passivating the ligands does not produce the ideal wurtzite structure and that Se atoms relax outwards irrespective of passivation. Here we show that implanted positrons are trapped at the surface of CdSe nanocrystals. They annihilate mostly with the Se electrons, monitor changes in composition and structure of the surface while hardly sensing the ligand molecules, and we thus unambiguously confirm the predicted strong surface relaxation. 相似文献
999.
Tom Schanz 《Bautechnik》2009,86(2):111-119
Deformation behaviour and crack initalisation of clay liner related to landfills – due to cyclic hydraulic and mechanic actions. Settlement and swell/shrink behaviour of clay liner under influence of environment are major topics of many research studies focussing expansive soil behaviour related to landfill applications. Depending on magnitude of surcharge pressure acting on the liner and wetting‐drying behaviour of the soil, settlement, together with swelling and shrinkage, may result in cracks or contrastly may close initial cracks induced by mechanical compaction in the field. In this paper, an analysis of the effects of field swelling and shrinkage of a compacted polymer‐enhanced bentonite‐sand mixture is presented. The analysis performed was based on field suction measurement data. Two different approaches; namely, single‐valued effective stress concept and two‐independent stress state variable approach for unsaturated soils were adopted in the analysis and comparison is presented in this paper. 相似文献
1000.
Patrick P. Naulleau Christopher N. Anderson Jerrin Chiu Paul Denham Simi George Kenneth A. Goldberg Michael Goldstein Brian Hoef Russ Hudyma Gideon Jones Chawon Koh Bruno La Fontaine Andy Ma Warren Montgomery Dimitra Niakoula Joo-on Park Tom Wallow Stefan Wurm 《Microelectronic Engineering》2009,86(4-6):448-455
Microfield exposure tools continue to play a dominant role in the development of extreme ultraviolet (EUV) resists. Here we present an update on the SEMATECH Berkeley 0.3-NA microfield exposure tool and summarize the latest test results from high-resolution line-space printing. Printing down to 20-nm is presented with large process latitude at 22-nm half-pitch lines. Also presented are line-edge roughness results along with a discussion of the importance of mask contributors to line-edge roughness measured in resist. Finally we briefly describe an upgrade to the tool that will enable EUV resist development at the 16-nm half-pitch node and beyond. (This paper was presented in MNE 2008 conference, <http://www.mne08.org>, <http://www.mne-conf.org>). 相似文献