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91.
In this study, real-time displacement measurement of bridges was carried out by means of digital image processing techniques.
This is innovative, highly cost-effective and easy to implement, and yet maintains the advantages of dynamic measurement and
high resolution. First, the measurement point is marked with a target panel of known geometry. A commercial digital video
camera with a telescopic lens is installed on a fixed point away from the bridge (e.g., on the coast) or on a pier (abutment),
which can be regarded as a fixed point. Then, the video camera takes a motion picture of the target. Meanwhile, the motion
of the target is calculated using image processing techniques, which require a texture recognition algorithm, projection of
the captured image, and calculation of the actual displacement using target geometry and the number of pixels moved. Field
tests were carried out for the verification of the present method. The test results gave sufficient dynamic resolution in
amplitude as well as the frequency. Use of this technology for a large suspension bridge is discussed considering the characteristics
of such bridges having low natural frequencies within 3 Hz and the maximum displacement of several centimeters. 相似文献
92.
Synthesis and Structural Characterization of a Binuclear Mixed‐Ligand (Salicylate and N,N‐diethylnicotinamide) Nickel(II) Complex,Its Magnetic Properties. [Ni2(µ‐Sal)4(Dena)2]H2O 下载免费PDF全文
The title complex of [Ni2(µ‐Sal)4(Dena)2]H2O, [( µ‐tetrakissalicylato‐κ‐O,O)(bis‐N,N‐diethylnicotinamide‐κ‐N)(binickel(II))]hydrate, C48H52Ni2N4O16, has been synthesized and explained as structural using some elemental analysis, FT‐IR spectra, UV‐Vis reflectance, magnetic measurements, thermal analysis and x‐ray diffraction methods. The analysis results showed that the unit cell of complex includes two molecules NiII cation, four molecules salicylates as bridge and two molecules N,N‐diethylnicotinamide ligands, also there is one molecule hydrated aqua. The compound crystallizes in the monoclinic space group P21/c with the following unit‐cell parameters: a =13.6776(6) Å, b =10.5238(3) Å, c =21.8165(9), α=90.00°, β=126.546(3)°, γ=90.00º and Z=2. The compound [Ni2(µ‐Sal)4(Dena)2]H2O is a typical paddle‐wheel complex structure. Two NiII ions are bridged by four salicylate ligands (O2, O2i, O3, O3i, O5, O5i, O6 and O6i) using a µ‐COO? coordination mode [symmetry code: (i) 1‐x, 1‐y, 1‐z]. Each NiII also coordinates to one nitrogen atom (N1 and N1i) from one N,N‐diethylnicotinamide ligand molecule in the axial position. The complex has strong paramagnetic properties. 相似文献
93.
基于对OZ 方程的渐近行为与Taylor级数展开的分析,提出了一个新的桥泛函,桥泛函被表达为间接相关函数的函数,Taylor级数展开的重整化导致了一个可调参数,通过将所提出的桥泛函与一个最近提出的密度泛函理论方法学,以及单个硬墙的sum 规则结合,可以确定可调参数.所提出的桥泛函能预言如下非均一流体的密度分布:硬球流体接近一个硬墙与在球形空隙内,Lennard-Jones 流体与缔合硬球流体在两个硬墙之内.理论预言与文献所报导的模拟数据符合很好. 相似文献
94.
CONFIRM: connecting fragments found in receptor molecules 总被引:1,自引:0,他引:1
Thompson DC Denny RA Nilakantan R Humblet C Joseph-McCarthy D Feyfant E 《Journal of computer-aided molecular design》2008,22(10):761-772
A novel algorithm for the connecting of fragment molecules is presented and validated for a number of test systems. Within the CONFIRM (Connecting Fragments Found in Receptor Molecules) approach a pre-prepared library of bridges is searched to extract those which match a search criterion derived from known experimental or computational binding information about fragment molecules within a target binding site. The resulting bridge 'hits' are then connected, in an automated fashion, to the fragments and docked into the target receptor. Docking poses are assessed in terms of root-mean-squared deviation from the known positions of the fragment molecules, as well as docking score should known inhibitors be available. The creation of the bridge library, the full details and novelty of the CONFIRM algorithm, and the general applicability of this approach within the field of fragment-based de novo drug design are discussed. 相似文献
95.
Dr. Gang Wang Yan Wu Dr. Zhujie Li Prof. Zaizhu Lou Qingqing Chen Yifan Li Prof. Dingsheng Wang Prof. Junjie Mao 《Angewandte Chemie (International ed. in English)》2023,62(13):e202218460
Developing highly efficient and stable photocatalysts for the CO2 reduction reaction (CO2RR) remains a great challenge. We designed a Z-Scheme photocatalyst with N−Cu1−S single-atom electron bridge (denoted as Cu-SAEB), which was used to mediate the CO2RR. The production of CO and O2 over Cu-SAEB is as high as 236.0 and 120.1 μmol g−1 h−1 in the absence of sacrificial agents, respectively, outperforming most previously reported photocatalysts. Notably, the as-designed Cu-SAEB is highly stable throughout 30 reaction cycles, totaling 300 h, owing to the strengthened contact interface of Cu-SAEB, and mediated by the N−Cu1−S atomic structure. Experimental and theoretical calculations indicated that the SAEB greatly promoted the Z-scheme interfacial charge-transport process, thus leading to great enhancement of the photocatalytic CO2RR of Cu-SAEB. This work represents a promising platform for the development of highly efficient and stable photocatalysts that have potential in CO2 conversion applications. 相似文献
96.
97.
叶锦春 《数学年刊A辑(中文版)》2002,(6)
本文对带跳的耦合正倒向随机微分方程引入了“桥”的概念,证明了如果两个带跳的耦合正倒向随机微分方程被桥连接着,那么它们有相同的唯一可解性.在此基础上,通过桥的构造,得到一些带跳的正倒向随机微分方程的唯一可解性. 相似文献