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Marcus E. Brewster Emil Pop Ming-Ju Huang Nicholas Bodor 《International journal of quantum chemistry》1996,60(8):1775-1787
Estimation of brain uptake of solutes and drugs would be useful in designing novel therapeutic agents. Given the problems associated with fragment-based models, including the need for strict additivity, we used AM1-derived molecular parameters in attempting to generate an equation for predicting the log of the brain-to-blood concentration ratios (log B:B) for a collection of compounds. Sequential fitting of the data using 10 AM1-derived variables indicated that dipole generated the most predictive one-term equation, dipole and log P, the best two-parameter system, dipole, log P, and molecular weight produced the optimal three-term model, and dipole, log P, molecular weight, and HOMO energy resulted in the best four-parameter paradigm. These systems were statistically similar to those generated using general solvation equations, but with the use of fewer parameters. An expanded parameter set may generated models of even better predictability. © 1996 John Wiley & Sons, Inc. 相似文献
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Phosphoramidate‐Supported Cp*IrIII Aminoborane H2B=NR2 Complexes: Synthesis,Structure, and Solution Dynamics 下载免费PDF全文
Marcus W. Drover Eric G. Bowes Prof. Dr. Laurel L. Schafer Prof. Dr. Jennifer A. Love Prof. Dr. Andrew S. Weller 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(20):6793-6797
Reaction of aminoboranes H2B=NR2 (R=iPr or Cy) with the cationic Cp*IrIII phosphoramidate complex [IrCp*{κ2‐N,O‐Xyl(N)P(O)(OEt)2}][BArF4] generates the aminoborane complexes [IrCp*(H){κ1‐N‐η2‐HB‐Xyl(N)P(OBHNR2)(OEt)2}][BArF4] (R=iPr or Cy) in which coordination of a P=O bond with boron weakens the B=N multiple bond. For these complexes, solution‐ and solid‐state, as well as DFT computational techniques, have been employed to substantiate B?N bond rotation of the coordinated aminoborane. 相似文献
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Mahboubeh Moslemi Mohammad Zakeri Mohammad Reza Rahimipour Marcus Schreiner 《Phase Transitions》2018,91(7):733-741
In this study, polycrystalline α-SiC composed of 55.7?wt.% 6H-SiC, 35.1?wt.% 4H-SiC with different volume fractions of carbon fibers (0–5–10–15–20%) was successfully sintered by spark plasma sintering technique at 2000°C and 35?MPa of applied pressure. The micrographs obtained from scanning electron microscopy revealed that the sintered samples were composed of equiaxed SiC grains. Results indicated that the presence of carbon fibers retarded the SiC densification process, decreased their relative densities and increased their porosity. Additionally, according to quantitative phase analysis by the Rietveld method during the sintering step, it was found that the 6H to 4H transformation has taken place. Increasing the carbon fibers content accelerated this trend as the sample containing 20?vol.% carbon fiber was consisted of 85.5?wt.% 4H-SiC. 相似文献
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