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71.
72.
For calculating the stiffness function of a structure, the differential equation of the vibration of the structure was divided into the differential equation on the original stiffness function that was known, and Fredholm integral equation of the first kind on the undetermined stiffness function that was unknown. And the stable solutions of the integral equation, when the smooth factor was equal to zero, was solved by the extrapolation with p smooth factors. So the stiffness function of the structure is obtained. Applied examples show that the method is feasible and effective. 相似文献
73.
Three unprecedented nitronyl nitroxide radical‐bridged 3d–4f clusters, [Ln2Cu2(hfac)10(NIT‐3py)2(H2O)2](LnIII=Y, Gd, Dy), have been obtained from the self‐assembly of Ln(hfac)3, Cu(hfac)2, and the radical ligand. The Dy complex shows a slow relaxation of magnetization, representing the first nitronyl nitroxide radical‐based 3d–4f cluster with single‐molecule magnet behavior. 相似文献
74.
75.
This paper presents the results of an experimental study on the heat transfer and pressure drop in diagonally finned tube banks. The investigations have been carried out using the napthalene analogy. The performance of a heat exchanger with fins arranged a certain angle to the flow direction with the plain tube heat exchanger have been compared. 相似文献
76.
77.
A new lanthanum coordination polymer formulated as {[La2(pyda) 2(μ4-SO4) ·5H2O]· 2H2O}n(1,H2pyda = 2,6-pyridine-dicarboxylic acid) has been synthesized from the reaction of H2pyda with lanthanide nitrate in the presence of sulfate as a counter anion. The compound was characterized by elemental analysis,IR spectroscopy and X-ray single-crystal diffraction. It crystallizes in the orthorhombic system,space group Pna21,with a = 18.8558(19) ,b = 6.5831(7) and c = 18.7543(19) . The compound is a 2D hybrid,in which the La(Ⅲ) ions were doubly connected by the carboxylic group of pyda2-ligand to form the La(Ⅲ) dimer followed by being grafted into 1D zig-zag chains which are further connected into a 2D network containing {[La(SO4) ]+}n helical chains. The interchain hydrogen bonding and π-π stacking interactions extended the 2D networks into a 3D supramolecular edifice. 相似文献
78.
Shandler SJ Korendovych IV Moore DT Smith-Dupont KB Streu CN Litvinov RI Billings PC Gai F Bennett JS DeGrado WF 《Journal of the American Chemical Society》2011,133(32):12378-12381
The design of β-peptide foldamers targeting the transmembrane (TM) domains of complex natural membrane proteins has been a formidable challenge. A series of β-peptides was designed to stably insert in TM orientations in phospholipid bilayers. Their secondary structures and orientation in the phospholipid bilayer was characterized using biophysical methods. Computational methods were then devised to design a β-peptide that targeted a TM helix of the integrin α(IIb)β(3). The designed peptide (β-CHAMP) interacts with the isolated target TM domain of the protein and activates the intact integrin in vitro. 相似文献
79.
Yue Gai Ling Ling Zhao Chang Qi Hu Hui Ping Zhang 《中国化学快报》2007,18(8):954-956
A new antifungal antibiotic,fusarielin E,was isolated from the marine-derived fungus Fusarium sp.Its structure was established on the basis of various NMR spectroscopic analyses and HR-FAB-MS.Fusarielin E displayed significant biological activity against Pyricularia oryzae. 相似文献
80.
根据扦插育苗试验表明,影响泰国赤桉苗高、根长及发根数的主要因素各不相同。综合分析表明:其主要因素是BA浓度,插条浸泡药液的时间和蔗糖浓度,其较优的插条处理方法是将插条在0.6%蔗糖+300PPmIBA溶液中浸泡2小时 相似文献