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261.
用于电子领域的高技术玻璃纤维织物 总被引:1,自引:0,他引:1
Alfred Watzl 《产业用纺织品》2005,23(10):42-43
在当今快速发展的不断微型化的先进电子技术领域里,玻璃纤维扮演着一个至关重要的角色,而这样的玻璃纤维织物经过福来斯拿AquaTex设备的处理,可以取得重要和有益的效果。这种新技术可以在不损伤极细的玻璃纤维(直径5μ)情况下,使玻璃纤维织物得到吏高的密度和更均匀的纤维分布。玻璃纤维是印刷电路板增强织物中的基材,所以它在电子市场的走向中起关键的作用。 相似文献
262.
Koen Faes Alfred Dhooge Patrick De Baets Paul Afschrift 《The International Journal of Advanced Manufacturing Technology》2009,40(9-10):982-992
CAD/CAM systems are the important interface for automating manufacturing processes to accommodate the varying market demands. However, they are often operated in an isolated environment and are unable to communicate with each other. Rapid development and enhancement of the network technology had made it possible for manufacturing processes to be implemented in a distributed environment. The purpose of this study is to develop a dispersed networked multi-axis surface manufacturing system. The proposed research uses the Integrated Definition for Function Modelling (IDEF0) methodology to analyze the manufacturing activities and adopts the Common Object Request Broker Architecture (CORBA) standard as the infrastructure of software components. Using IDEF0, the manufacturing activities can be analyzed and represented as a hierarchical and structural functional model. The developed system has the “plug-and-play” capability and can be integrated with other development teams to achieve information sharing. On-line test of the prototype system has been implemented collaboratively by three development teams and the effectiveness of the developed system has also been confirmed. The developed system has successfully integrated resources of different locations through a network and can effectively reduce the product development and manufacturing time, thus enhancing the global competitiveness of the industry. 相似文献
263.
Usha Thiyam Pickardt Claudia Ungewiss Jan Baumert Alfred 《European Food Research and Technology》2009,229(5):825-831
De-oiled rapeseed is a rich source of proteins and phenolic compounds. The phenolic compounds, namely sinapic acid derivatives
(SAD), could occur as free sinapic acid, esterified (as sinapine, the choline ester of sinapic acid) and decarboxylated (as
canolol) forms. Rapeseed protein preparations containing very low phenolic compounds have been the focus of our ongoing research.
A precipitated rapeseed protein isolate is investigated for SAD such as sinapine, sinapoyl glucose, canolol using HPLC–DAD
and LC–MS. Profile of the phenolic compounds of de-oiled rapeseed, press cakes and the precipitated protein isolate are compared.
HPLC–DAD analysis indicated SAD; particularly sinapine is the main phenolic compound of all the substrates. The protein derivation
process did not remarkably alter the profile of the investigated protein isolate. 相似文献
264.
New optical coating design algorithm with the equivalent layers theory is presented. The algorithm is based on the merit-function-constrained optimization in the accessible domain of equivalent phase thicknesses and equivalent refractive indices. It allows for creation of design coatings with sophisticated narrowband spectral characteristics. ( 相似文献
265.
266.
Mario Siewert Markus E. Gruner Alfred Hucht Heike C. Herper Antje Dannenberg Aparna Chakrabarti Navdeep Singh Raymundo Arróyave Peter Entel 《Advanced Engineering Materials》2012,14(8):530-546
The interplay of structural and magnetic properties of magnetic shape memory alloys is closely related to their composition. In this study the influence of the valence electron concentration on the tetragonal transformation in Ni2Mn1 + xZ1 ? x (Z = Ga, In, Sn, Sb) and Co2Ni1 + xGa1 ? x is investigated by means of ab initio calculations. While the type of magnetic interaction is different for the two series, the trends of the total energy changes under a tetragonal transformation are very similar. We find that tetragonal structures become energetically preferred with respect to the cubic one as the valence electron concentration e/a is increased regardless of the system under consideration. In particular, the energy difference between the austenite and martensite structures increases linearly with e/a, which is in part responsible for the linear increase of the matensite transformation temperature. The substitution of nickel by platinum increases even further the transformation temperature. 相似文献
267.
Vasylkiv O Borodianska H Badica P Grasso S Sakka Y Tok A Su LT Bosman M Ma J 《Journal of nanoscience and nanotechnology》2012,12(2):959-965
Boron carbide B4C powders were subject to reactive spark plasma sintering (also known as field assisted sintering, pulsed current sintering or plasma assisted sintering) under nitrogen atmosphere. For an optimum hexagonal BN (h-BN) content estimated from X-ray diffraction measurements at approximately 0.4 wt%, the as-prepared BaCb-(BxOy/BN) ceramic shows values of Berkovich and Vickers hardness of 56.7 +/- 3.1 GPa and 39.3 +/- 7.6 GPa, respectively. These values are higher than for the vacuum SPS processed B4C pristine sample and the h-BN -mechanically-added samples. XRD and electronic microscopy data suggest that in the samples produced by reactive SPS in N2 atmosphere, and containing an estimated amount of 0.3-1.5% h-BN, the crystallite size of the boron carbide grains is decreasing with the increasing amount of N2, while for the newly formed lamellar h-BN the crystallite size is almost constant (approximately 30-50 nm). BN is located at the grain boundaries between the boron carbide grains and it is wrapped and intercalated by a thin layer of boron oxide. BxOy/BN forms a fine and continuous 3D mesh-like structure that is a possible reason for good mechanical properties. 相似文献
268.
Xie SS Su LT Guo J Vasylkiv O Borodianska H Xi Z Krishnan GM Su H Tokl AI 《Journal of nanoscience and nanotechnology》2012,12(1):596-603
Boron Carbide is one the hardest and lightest material that is also relatively easier to synthesis as compared to other superhard ceramics like cubic boron nitride and diamond. However, the brittle nature of monolithic advanced ceramics material hinders its use in various engineering applications. Thus, strategies that can toughen the material are of fundamental and technological importance. One approach is to use nanostructure materials as building blocks, and organize them into a complex hierarchical structure, which could potentially enhance its mechanical properties to exceed that of the monolithic form. In this paper, we demonstrated a simple approach to synthesize one- and two-dimension nanostructure boron carbide by simply changing the mixing ratio of the initial compound to influence the saturation condition of the process at a relatively low temperature of 1500 degrees C with no catalyst involved in the growing process. Characterization of the resulting nano-structures shows B13C2, which is a superhard phase of boron carbide as its hardness is almost twice as hard as the commonly known B4C. Using ab-initio density functional theory study on the elastic properties of both B12C3 and B13C2, the high hardness of B13C2 is consistent to our calculation results, where bulk modulus of B13C2 is higher than that of B4C. High resolution transmission electron microscopy of the nanoflakes also reveals high density of twinning defects which could potentially inhibit the crack propagation, leading to toughening of the materials. 相似文献
269.
Li H Yin Z He Q Li H Huang X Lu G Fam DW Tok AI Zhang Q Zhang H 《Small (Weinheim an der Bergstrasse, Germany)》2012,8(1):63-67
Single- and multilayer MoS(2) films are deposited onto Si/SiO(2) using the mechanical exfoliation technique. The films were then used for the fabrication of field-effect transistors (FETs). These FET devices can be used as gas sensors to detect nitrous oxide (NO). Although the single-layer MoS(2) device shows a rapid response after exposure to NO, the current was found to be unstable. The two-, three-, and four-layer MoS(2) devices show both stable and sensitive responses to NO down to a concentration of 0.8 ppm. 相似文献
270.
Kratz K Narasimhan A Tangirala R Moon S Revanur R Kundu S Kim HS Crosby AJ Russell TP Emrick T Kolmakov G Balazs AC 《Nature nanotechnology》2012,7(2):87-90
Nanoparticles have useful properties, but it is often important that they only start working after they are placed in a desired location. The encapsulation of nanoparticles allows their function to be preserved until they are released at a specific time or location, and this has been exploited in the development of self-healing materials and in applications such as drug delivery. Encapsulation has also been used to stabilize and control the release of substances, including flavours, fragrances and pesticides. We recently proposed a new technique for the repair of surfaces called 'repair-and-go'. In this approach, a flexible microcapsule filled with a solution of nanoparticles rolls across a surface that has been damaged, stopping to repair any defects it encounters by releasing nanoparticles into them, then moving on to the next defect. Here, we experimentally demonstrate the repair-and-go approach using droplets of oil that are stabilized with a polymer surfactant and contain CdSe nanoparticles. We show that these microcapsules can find the cracks on a surface and selectively deliver the nanoparticle contents into the crack, before moving on to find the next crack. Although the microcapsules are too large to enter the cracks, their flexible walls allow them to probe and adhere temporarily to the interior of the cracks. The release of nanoparticles is made possible by the thin microcapsule wall (comparable to the diameter of the nanoparticles) and by the favourable (hydrophobic-hydrophobic) interactions between the nanoparticle and the cracked surface. 相似文献