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1.
Giang Truong Nguyen Prof. Dr. Liviu Ungur 《Chemistry (Weinheim an der Bergstrasse, Germany)》2022,28(30):e202200227
Employing radical bridges between anisotropic metal ions has been a viable route to achieve high-performance single-molecule magnets (SMMs). While the bridges have been mainly considered for their ability to promote exchange interactions, the crystal-field effect arising from them has not been taken into account explicitly. This lack of consideration may distort the understanding and limit the development of the entire family. To shed light on this aspect, herein we report a theoretical investigation of a series of N -radical-bridged diterbium complexes. It is found that while promoting strong exchange coupling between the terbium ions, the N -radical induces a crystal field that interferes destructively with that of the outer ligands, and thus reduces the overall SMM behavior. Based on the theoretical results, we conclude that the SMM behavior in this series could be further maximized if the crystal field of the outer ligands is designed to be collinear with that of the radical bridge. This conclusion can be generalized to all exchange-coupled SMMs. 相似文献
2.
A numerical model was developed and validated to investigate the fluid–structure interactions between fully developed pipe flow and core–shell-structured microcapsule in a microchannel. Different flow rates and microcapsule shell thicknesses were considered. A sixth-order rotational symmetric distribution of von Mises stress over the microcapsule shell can be observed on the microcapsule with a thinner shell configuration, especially at higher flow rate conditions. It is also observed that when being carried along in a fully developed pipe flow, the microcapsule with a thinner shell tends to accumulate stress at a higher rate compared to that with a thicker shell. In general, for the same microcapsule configuration, higher flow velocity would induce a higher stress level over the microcapsule shell. The deformation gradient was used to capture the microcapsule's deformation in the present study. The effect of Young's modulus on the microcapsule shell on the microcapsule deformation was investigated as well. Our findings will shed light on the understanding of the stability of core–shell-structured microcapsule when subjected to flow-induced shear stress in a microfluidic system, enabling a more exquisite control over the breakup dynamics of drug-loaded microcapsule for biomedical applications. 相似文献
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基于高陡横坡段桩柱式桥梁双桩基础承载特性,提出了一种改进有限杆单元计算分析方法.分析了高陡横坡段桩柱式桥梁双桩基础承载机理及受力特性,建立了双桩基础计算分析模型.其次,根据前、后桩与边坡相对位置关系,给出了后桩所受剩余下滑力与前桩所受土压力的比例关系.在传统有限杆单元分析方法基础上,结合陡坡桩受力特征,导得了考虑桩土共同作用与"P-Δ"效应的单元刚度矩阵修正方法,并在此基础上编制了适用于高陡横坡段桩柱式桥梁双桩基础的有限杆单元分析MATLAB计算程序.采用室内模型试验对本文计算方法进行验证,给出了适用于陡坡段桥梁桩基的设计流程图.研究结果表明:本文理论计算值与模型试验实测结果吻合良好,表明本文计算方法正确可行,可为同类工程设计提供参考. 相似文献
6.
Functional Binding Surface of a β‐Hairpin VEGF Receptor Targeting Peptide Determined by NMR Spectroscopy in Living Cells 下载免费PDF全文
Dr. Donatella Diana Anna Russomanno Dr. Lucia De Rosa Dr. Rossella Di Stasi Dr. Domenica Capasso Dr. Sonia Di Gaetano Dr. Alessandra Romanelli Dr. Luigi Russo Dr. Luca D. D'Andrea Prof. Roberto Fattorusso 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(1):91-95
In this study, the functional interaction of HPLW peptide with VEGFR2 (Vascular Endothelial Growth Factor Receptor 2) was determined by using fast 15N‐edited NMR spectroscopic experiments. To this aim, 15N uniformly labelled HPLW has been added to Porcine Aortic Endothelial Cells. The acquisition of isotope‐edited NMR spectroscopic experiments, including 15N relaxation measurements, allowed a precise characterization of the in‐cell HPLW epitope recognized by VEGFR2. 相似文献
7.
Surimi from silver carp with different salt contents (0–5%) was obtained treated by high intensity ultrasound (HIU, 100 kHz 91 W·cm−2). The gelation properties of samples were evaluated by puncture properties, microstructures, water-holding capacity, dynamic rheological properties and intermolecular interactions. As the salt content increased from 0 to 5%, gel properties of surimi without HIU significantly improved. For samples with low-salt (0–2% NaCl) content, HIU induced obvious enhancement in breaking force and deformation. HIU promoted the protein aggregation linked by SS bonds, hydrophobic interactions and non-disulfide covalent bonds in surimi gels with low-salt content. Moreover, microstructures of HIU surimi gels with low-salt content were more compact than those of the corresponding control samples. HIU also improved the gelation properties of surimi with 3% NaCl to an extent. However, for high-salt (4–5% NaCl) samples, HIU decreased the breaking force and deformation of surimi gels due to the degradation of proteins suggested by increased TCA-soluble peptides. In conclusion, HIU effectively improved the gelation properties of surimi with low-salt content (0–2% NaCl), but was harmful for high-salt (4–5% NaCl) surimi. This might provide the theoretical basis for the production of low-salt surimi gels. 相似文献
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关于经济法的调整对象历来是经济法学甚至包括民法学、行政法学界争执的一个焦点,但是大家还是就经济法的基本理念达成了共识,即经济法是国家干预市场经济的基本法律形式,鉴于我国完全不同于西方的市场进化模式,当前我国国家干预市场的范围应当严格限定,干预市场与培育市场应当两种手段并存.经济法以社会公共利益为本位的法益追求是经济法区别于传统的公法和私法独立存在的根本理由.在此基础上再界定经济法的调整对象也就不再困难. 相似文献
9.
从理论上分析提出了弱相互作用下Bose体系的BEC理论,并由此来解释液^4He的超流性。通过深入对比理想Bose气体和弱相互作用下Bose体系发生BEC性质的不同,分析得出了凝聚体系粒子间相互作用的有无是导致二者性质不同的主要原因。 相似文献
10.
LaMnO3不同晶位掺杂的磁电阻效应 总被引:2,自引:0,他引:2
任清褒 《西安交通大学学报》2004,38(6):645-648,656
基于研究钙钛矿型氧化物磁电阻效应的目的,采用固相反应法制备了实验所需的单相多晶样品,主要就La位二价金属离子掺杂和稀土互掺及Mn位掺杂对LaMnO3磁电阻影响的实验结果作比较研究,发现La位稀土互掺对磁电阻的影响可以用晶格效应来解释,并明确指出La位和Mn位掺杂是提高和调制钙钛矿型锰氧化物超大磁电阻效应的一种有效途径. 相似文献