排序方式: 共有39条查询结果,搜索用时 78 毫秒
1.
Dimosthenis Sokaras Euthimios BistekosLambros Georgiou Joseph Salomon Mladen BogovacEleni Aloupi-Siotis Vasilis PaschalisIoanna Aslani Sofia KarabagiaAnastasios Lagoyannis Sotirios HarissopulosVasiliki Kantarelou Andreas-Germanos Karydas 《Nuclear instruments & methods in physics research. Section B, Beam interactions with materials and atoms》2011,269(5):519-527
At the 5.5 MV Tandem VdG accelerator of the Institute of Nuclear Physics of N.C.S.R. “Demokritos”, Athens, Greece, an external ion-beam set-up has been recently developed and installed. The aim of this development was to integrate the analytical capabilities of the PIXE, RBS and PIGE ion beam techniques in one experimental set-up, so that to attain a complete elemental and near surface structural characterization of samples in an almost non-destructive way and without any limitation concerning their size or conductive state. A careful 3D mechanical drawing optimized the set-up experimental parameters achieving probe dimensions at the millimeter range (1 mm2) and fulfilling the special requirements imposed for optimum performance of the aforementioned techniques, including the possibility to use heavier, than protons, ion beams. For the digital pulse processing of the X-ray, γ-ray and charged particle detector signals, novel hardware and software tools were developed based on a custom FPGA configuration.The first applications were focused in the quality control of materials that have been intentionally contaminated with a particular tracer-element (“tagged” materials). The tagged materials which were developed and tested are technologically authentic replicas of ancient attic ceramics with black glazed decoration. Analytical diagnostic studies were carried out for a few representative paintings of contemporary Greek painters in order to identify and document materials/pigments and techniques and eventually to prevent trade of fakes. Finally, ancient glass beads were also examined with respect to the sodium concentration and its in-depth homogeneity. 相似文献
2.
T Plant growth and morphogenesis depend on the levels and distribution of the plant hormone auxin. Plants tightly regulate cellular levels of the active auxin indole-3-acetic acid (IAA) through synthesis, inactivation, and transport. Although the transporters that move IAA into and out of cells are well characterized and play important roles in development, little is known about the transport of IAA precursors. In this review, we discuss the accumulating evidence suggesting that the IAA precursor indole-3-butyric acid (IBA) is transported independently of the characterized IAA transport machinery along with the recent identification of specific IBA efflux carriers and enzymes suggested to metabolize IBA. These studies have revealed important roles for IBA in maintaining IAA levels and distribution within the plant to support normal development. 相似文献
3.
Branko Kolarevic 《Architectural Design》2015,85(5):128-133
An emphasis on material synthesis is not without its pitfalls and challenges. Here Branko Kolarevic , Professor and Chair in Integrated Design at the University of Calgary Faculty of Environmental Design, alerts us to the dangers of overlooking materials' shifting capacities, which are so often scale dependent, while also disregarding existing materials in favour of the new or novel. As the potential grows for material systems in buildings to become more adaptive and to harness automation, Kolarevic describes some exciting developments that are taking place in dynamic facade design, providing the much-heralded promise of an efficient use of ambient energy. 相似文献
4.
Shifting the focus from futuristic visions, Alfredo Brillembourg and Hubert Klumpner with Alexis Kalagas of interdisciplinary design practice Urban-Think Tank urge us to ‘forget about utopia’, for in the most part the urban environment of 2050 is already built. Architects’ sights need to be set on the sometimes grim and unfolding reality of favelas and the world's informal cities. 相似文献
5.
随着InfiniBand协议的日益流行,相应的网络产品也越来越多.应用规模的增加,也随之带来新的问题,如何管理、测试和维护这种新兴网络,已经成为工程师面前的新课题.IBA协议支持各种形式的网络拓扑,不同的管理维护策略适用于不同的网络;研究了多种网络结构后,对一种树形的网络拓扑,给出了网络管理系统的设计及其中诊断系统的实现策略. 相似文献
6.
7.
本文以福建省超级计算中心为例,探讨了搭建基于IBA架构的高性能集群计算工程的简易模式,包括IBA架构、计算节点设计、操作系统设计等相关技术。 相似文献
8.
Xu Y Zhang Y Li Y Li G Liu D Zhao M Cai N 《International journal of molecular sciences》2012,13(5):6507-6520
A field experiment was conducted using a 3 × 3 orthogonal regression design to explore the growth promotion of one-year-old Yunnan pine seedlings (Pinus yunnanensis Franch.) in response to foliar application of IAA (indole-3-acetic acid) at rates of 0, 200 and 400 mg·L(-1) and IBA (indole-3-butyric acid) at rates of 0, 200 and 400 mg·L(-1) in order to promote the growth during the seedlings' early stage. The experiment was conducted at the Lufeng Village Forest Farm of Yiliang County in Kunming, Yunnan, China. The results showed that IAA and IBA were effective in growth promotion of Yunnan pine seedlings. The response of both growth increment and biomass accumulation to the concentration of IAA and IBA can be modeled using a bivariate surface response, and each growth index had a peak value. Growth indexes increased with the increase of the dosage of photohormones before reaching a peak value, and then decreased. The different growth indexes had various responses to the concentrations and ratio of IAA and IBA. The foliar application of IAA in combination with IBA showed the largest improvement on the biomass of the needles, followed by stems and roots. The higher ratio of IAA promoted stem diameter growth, root system development and biomass accumulation in the needles, while a higher ratio of IBA contributed to height growth and biomass accumulation in the stem. Based on the auxin effect equations on the different growth indexes and surface response, the optimum concentrations and the (IAA:IBA) ratios can be obtained. The optimum concentrations of IAA and IBA were 167 and 186, 310 and 217, 193 and 159, 191 and 221, and 206 and 186 mg·L(-1), with corresponding ratios of 1:1.11, 1:0.70, 1:0.82, 1:1.15 and 1:0.90, respectively, at the maximum seedling height and collar diameter growth as well as biomass accumulation at the root, stem and needle. The above growth indexes were 22.00%, 79.80%, 48.65%, 82.20% and 107.00% higher than the control treatment. 相似文献
9.
10.
一种IBA规则网络的路由算法及其网络模拟 总被引:1,自引:0,他引:1
InfiniBand协议越来越得到网络互连界的认可。它定义了一种自由的网络拓扑。目前多数场合使用的是不规则IBA网络,采用通用的up/down路由算法;但是将up/down算法直接用于IBA网络时,需要以损失网络性能为代价的路径修正才能避免网络死锁[1,2]。为了满足用户的特殊需求,保证网络的高带宽、低延迟,构造了基于4元N树的IBA规则网络拓扑,给出其单播和多播路由算法,并建立一个较为完整的IBA系统模型,用于模拟网络的可行性以及算法的正确性。 相似文献