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101.
102.
Radiophysics and Quantum Electronics - We consider whether it is possible in principle to retrieve the key parameters of the mixed layer in the upper ocean (its thickness, bulk eddy viscosity and... 相似文献
103.
Rongzhen Wu Hongyu Chen Dr. Ninghui Chang Yuzhi Xu Prof. Dr. Jiao Jiao Prof. Dr. Hailong Zhang 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(6):1166-1195
Bryostatins are a class of naturally occurring macrocyclic lactones with a unique fast developing portfolio of clinical applications, including treatment of AIDS, Alzheimer's disease, and cancer. This comprehensive account summarizes the recent progress (2014–present) in the development of bryostatins, including their total synthesis and biomedical applications. An emphasis is placed on the discussion of bryostatin 1 , the most-studied analogue to date. This review highlights the synthetic and biological challenges of bryostatins and provides an outlook on their future development. 相似文献
104.
105.
Vanessa R. Machado Louis P. Sandjo Giovanni L. Pinheiro Milene H. Moraes Mario Steindel Moacir G. Pizzolatti 《Natural product research》2018,32(3):275-281
The natural product lupeol 1 was isolated from aerial parts of Vernonia scorpioides with satisfactory yield, which made it viable to be used as starting material in semisynthetic approach. Ten lupeol derivatives 2–11 were prepared by classical procedures. Including, five new esters derivatives 7–11, which were obtained by structural modifications in the isopropylidene fragment. All semisynthetic compounds and lupeol 1–11 were confirmed by 1H NMR, 13C NMR and HRMS. Their antiprotozoal activity was evaluated in vitro against L. amazonensis and T. cruzi. Derivative 6 showed the best antitrypanosomal activity (IC50 = 12.48 μg/mL) and the lowest cytotoxic derivative (CC50 = 161.50 μg/mL). The mechanism of action of the most active derivatives (4, 6 and 11) is not dependent from the enzyme trypanothione reductase. 相似文献
106.
107.
R. Notoya 《Russian Journal of Electrochemistry》2002,38(3):255-260
It is found that the density (number of the component ion or molecule in 1 cm3) of a molten salt could be expressed as a function of the product of the electron donating and accepting properties of the component anion and cation. This equation is very useful for estimating the density of any molten salt at high temperature with the standard deviation accurately. 相似文献
108.
109.
Investigated is the dependency of the crack tip opening displacement (CTOD) on the local microstructure of the heat affected zone in high-strength low-alloy (HSLA) microalloyed steel. Since the initiation of the crack tip location could not be controlled in fatigue, any possible correlation between heat iput in welding and fracture toughness could be smeared. Modified CTOD data are defined; they show that the fracture resistance of the weld joint decreased as the heat input increased. 相似文献
110.
An analysis is made of the conditions of formation and the stability region of static-soliton-type magnetic nonuniformities
in a (001)-crystal plate with combined anisotropy. It is shown that if demagnetizing fields in the plate are taken into account,
static solitons can localize at certain defects for appropriate parameters of the material. The soliton stability region was
found to be bounded by two extreme values of the material parameters, namely, those at which the soliton is unstable against
collapse and at which it expands. It was also found that the soliton stability region differs considerably from that predicted
theoretically in the model disregarding the finite size of the sample and the presence of defects.
Fiz. Tverd. Tela (St. Petersburg) 40, 1498–1502 (August 1998) 相似文献