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排序方式: 共有96条查询结果,搜索用时 15 毫秒
1.
Dr. Peng Zhang Qian-Cheng Luo Dr. Zhenhua Zhu Wanrong He Nan Song Junting Lv Xuning Wang Prof. Quan-Guo Zhai Prof. Yan-Zhen Zheng Prof. Jinkui Tang 《Angewandte Chemie (International ed. in English)》2023,62(12):e202218540
The syntheses and magnetic properties of organometallic heterometallic compounds [K(THF)6]{CoI[(μ3-HAN)RE2Cp*4]2} ( 1-RE ) and [K(Crypt)]2{CoI[(μ3-HAN)RE2Cp*4]2} ( 2-RE ) containing hexaazatrinaphthylene radicals (HAN⋅3−) and four rare earth (RE) ions are reported. 1-RE shows isolable species with ligand-based mixed valency as revealed by cyclic voltammetry (CV) thus leading to the isolation of 2-RE via one-electron chemical reduction. Strong electronic communication in mixed-valency supports stronger overall ferromagnetic behaviors in 2-RE than 1-RE containing Gd and Dy ions. Ac magnetic susceptibility data reveal 1-Dy and 2-Dy both exhibit slow magnetic relaxation. Importantly, larger coercive field was observed in the hysteresis of 2-Dy at 2.0 K, indicating the enhanced SMM behavior compared with 1-Dy . Ligand-based mixed-valency strategy has been used for the first time to improve the magnetic coupling in lanthanide (Ln) SMMs, thus opening up new ways to construct strongly coupled Ln-SMMs. 相似文献
2.
In this paper, we develop a method to estimate the bridge deflection using fiber optic Bragg-grating (FBG) strain sensors.
For most structural evaluation of bridge integrity, it is very important to measure the geometric profile, which is a major
factor representing the global behavior of civil structures, especially bridges. In the past, because of the lack of appropriate
methods to measure the deflection curve of bridges on site, the measurement of deflection has been restricted to just a few
discrete points along the bridge, and the measuring points have been limited to the locations installed with displacement
transducers. However, by applying classical beam theory, a formula is rearranged to estimate the continuously deflected profile
by using strains measured directly from several points. In addition, FBG strain sensors, which are electromagnetic, noise-free
and multipoint measurable, are employed to obtain flexural strains more accurately and stably. The regression analysis is
performed to obtain a strain function from the measured strain data. Finally, the deflection curve can be estimated by applying
the strain function to the formula. An experimental test has also been carried out to verify the developed method. 相似文献
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斜拉桥塔锚固区光弹性应力分析与等倾线图像处理 总被引:1,自引:2,他引:1
本文采用光弹性冻结应力法,对独塔斜拉桥塔锚固区进行了应力分析,给出了有关截面的边界应力分布及主应力迹线,从而为优化工程设计提供了重要的参考依据。本文还提出了一种新的提取等倾线的方法──图像对数增强相减法,实现了等倾线与等差线条纹的分离,同时使条纹得到了细化,提高了处理等倾线的速度与准确度。编制了自动绘制主应力迹线的程序,利用它绘制了桥塔截面的次主应力迹线。 相似文献
6.
利用粗粒化分子动力学(CGMD)方法研究了两亲性接枝共聚物在不同选择性溶剂中的自组装行为.分析了主链刚性及链长对自组装结构的影响.研究结果表明,当溶剂对主链为良溶剂而对支链为不良溶剂时,两亲性接枝共聚物随主链刚性的增加自组装形成花状胶束、花桥状胶束及桥状胶束,并且组分比例对自组装结构影响很大;随着链长的增加,柔性链出现单花状胶束到多花状胶束的转化.当溶剂对主链为不良溶剂而对支链为良溶剂时,可得到近球形或椭球形核壳状胶束及束状结构;不同链长时,柔性接枝共聚物链均只能得到近球形的单核壳状胶束. 相似文献
7.
This paper describes a perspective for information versatile disk for removable usage (iVDR) business. iVDR is the best bridge media for high-resolution image because of high capacity and high reliability. The first iVDR product was delivered with PMR technology hard disk drives and a copyright protection function for high-definition TV programs. The business opportunity and the new business model are discussed. 相似文献
8.
Non-stationary aeroelastic wind force processes on a streamlined bridge deck are modelled for use within computations in the range of statistically stationary girder oscillation and for the mathematical investigation of the limit of aeroelastic stability. Time Domain (TD) methods, as the direct integration on a finite-element (FE) model, are applied in structural analyses for taking into consideration both geometric and physical nonlinearities. The FE method requires a continuous form of the force model, which permits an arbitrary discretization in time. The present model is based on continuous step response functions of Wagner-type, taking advantage of modern advances of that theory. Special emphasis is put on the continuity and the existence of equivalent representations in time and frequency domains. A realistic wind load model must include measured force functions and effects from the wind turbulence. For that reason, the force functions are calibrated in wind tunnel tests on section models in grid turbulence and boundary layer flow. The aeroelastic in-phase and out-of-phase forces are identified from highly accurate calibrations experiments on section models up to high frequencies which permits to decrease the time step increment. Turbulence effects on the aeroelastic coefficients are included in mean terms. 相似文献
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10.
《Electroanalysis》2018,30(8):1734-1739
The present study describes a novel electrochemical aptasensor for detection of carcinoembryonic antigen (CEA), a key cancer biomarker. The sensing strategy relied on the CEA‐induced bridge assembly, as a physical barrier, on the surface of gold electrode, resulting in a significant increase of the sensor sensitivity. Under optimal conditions, the aptasensing platform showed a wide linear range (3 pg/mL to 40 ng/mL) and a low detection limit (0.9 pg/mL). Some possible interfering materials were also assessed and the results indicated that the designed aptasensor had good specificity toward CEA. The quantitation of CEA in the spiked human serum samples confirmed the reliability and applicability of the electrochemical aptasensor. So, the developed sensing method has a potential application in the clinical diagnosis. 相似文献