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81.
This paper describes the use of a rotating all-mirror image derotator system, high-speed video and particle image velocimetry (PIV) to visualise and quantitatively examine the flow patterns between the blades of a centrifugal impeller. The flow field relative to the moving centrifugal impeller is presented. Published online: 13 December 2002  相似文献   
82.
The design of biologically inspired, multi-component cascade reactions enables the targeted synthesis of assorted structurally complex products. Similar to regulation in cells the reaction path is controlled by the substrate concentration and complex enantiopure products with high structural diversity are provided.  相似文献   
83.
In this note, we give a positive answer to a question of Dimca and Greuel about the quotient between the Milnor and Tjurina numbers of an isolated plane curve singularity in the cases of one Puiseux pair and semi-quasi-homogeneous singularities.  相似文献   
84.
Blanco  A. 《Positivity》2019,23(2):485-491
Positivity - We consider the question of when is every positive compact operator, between two given Banach lattices, approximable regular. An immediate consequence of our main result is that,...  相似文献   
85.
The coexistence of leishmaniasis, Chagas disease, and neoplasia in endemic areas has been extensively documented. The use of common drugs in the treatment of these pathologies invites us to search for new molecules with these characteristics. In this research, we report 16 synthetic chalcone derivatives that were investigated for leishmanicidal and trypanocidal activities as well as for antiproliferative potential on eight human cancers and two nontumor cell lines. The final compounds 8–23 were obtained using the classical base-catalyzed Claisen–Schmidt condensation. The most potent compounds as parasiticidal were found to be 22 and 23, while compounds 18 and 22 showed the best antiproliferative activity and therapeutic index against CCRF-CEM, K562, A549, and U2OS cancer cell lines and non-toxic VERO, BMDM, MRC-5, and BJ cells. In the case of K562 and the corresponding drug-resistant K562-TAX cell lines, the antiproliferative activity has shown a more significant difference for compound 19 having 10.3 times higher activity against the K562-TAX than K562 cell line. Flow cytometry analysis using K562 and A549 cell lines cultured with compounds 18 and 22 confirmed the induction of apoptosis in treated cells after 24 h. Based on the structural analysis, these chalcones represent new compounds potentially useful for Leishmania, Trypanosoma cruzi, and some cancer treatments.  相似文献   
86.
87.
A discrete velocity model is presented for lattice Boltzmann thermal fluid dynamics. This model is implemented and tested in two dimensions with a finite difference scheme. Comparison with analytical solutions shows an excellent agreement even for wide temperature differences. An alternative approximate approach is then presented for traditional lattice transport schemes  相似文献   
88.
The 13C‐NMR spectra of some 1,6‐naphthyridines 2 and 1,7‐naphthyridines 3 , as well as those of N‐methyl derivatives 4 and 5 , were recorded and analyzed. Results in dimethyl‐d6 sulfoxide and deuteriochlo‐roform provide useful data on intra and intermolecular hydrogen bonds.  相似文献   
89.
The water solubility of 1,3,5,7-tetra azatricyclo[3.3.1.13,7]decane, hexamethylenetetramine (HMT) or urotropine was determined at temperatures between 275.15 K and 313.15 K. Van’t Hoff graphs of ln msat versus 1/T gave three different straight lines, suggesting the existence of three different forms of the substance in the temperature region studied.

Previous work reported both increasing and decreasing solubility with temperature. This work found the solubility does not have a simple behavior.  相似文献   

90.
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