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71.
Trump RP Blanc JB Stewart EL Brown PJ Caivano M Gray DW Hoekstra WJ Willson TM Han B Turnbull P 《Journal of combinatorial chemistry》2007,9(1):107-114
We describe the design, using shape comparison and fast docking computer algorithms, and rapid parallel synthesis of a 1300 member array based on GSK7721, a 4-aminobenzonitrile androgen receptor (AR) antagonist identified by focused screening of the GSK compound collection. The array yielded 352 submicromolar and 17 subnanomolar AR agonists as measured by a cell-based reporter gene functional assay. The rapid synthesis of a large number of active compounds provided valuable information in the optimization of AR modulators, which may be useful in treating androgen deficiency in aging males. 相似文献
72.
73.
Elly Hoekstra Sascha R.A. Kersten A. Tudos Dietrich Meier Kees J.A. Hogendoorn 《Journal of Analytical and Applied Pyrolysis》2011,91(1):76-88
The applicability of size exclusion chromatography (SEC) to analyze (upgraded) pyrolysis oil samples has been studied using model compounds, pyrolysis oils and hydrodeoxygenated pyrolysis oils. The assumptions needed for the conversion of the chromatogram to the Mw-distribution were validated. It was shown that the conversion of elution volume to molecular weight (based on polystyrene calibration curves) can introduce substantial errors in the prediction of the molecular weight. The conversion of RID response to W(log M) (as plotted on the y-axis of the Mw-distribution) is based on the assumption of a compound independent RID response factor and linear response to concentration. While the latter was shown to be true within the concentration range studied, the former was not true: the RID response factor depends on the type of (upgraded) pyrolysis oil. It was shown that within a single pyrolysis oil sample, the RID response for the low molecular weight fraction was a factor 3 lower than the high molecular weight fraction. Furthermore long term column fouling can influence SEC results that cannot be corrected with regular polystyrene recalibrations.Based on the results we recommend SEC not to be used as a quantitative method for characterization (upgraded) pyrolysis oil samples, but as a tool to compare (upgraded) pyrolysis oil samples, preferably prepared using incremental operating conditions and expected to have similar molecular composition. This work has further shown that (i) the ∫UVDdv/∫RIDdv ratio can be used as an indication of the sum of the relative aromaticity and conjugated double bond content for (upgraded) pyrolysis oil, and (ii) the negative peak area appearing in the low molecular weight part of the chromatogram can be used to estimate the water content of (upgraded) oil samples. 相似文献
74.
采用具有紫外光聚合性能的聚乙二醇(PEG)基水凝胶材料, 通过紫外光聚合作用快速加工双层水凝胶微流控芯片, 并验证了其对肿瘤细胞代谢液进行检测的可行性. 与传统微流控芯片材料相比, 该水凝胶芯片材料具有更好的生物相容性及可操控性, 可直接加工成形, 在生物学领域特别是细胞培养过程控制方面具有良好的应用前景. 实验结果表明, 该水凝胶微流控芯片可在微尺度空间有效模拟细胞生长环境, 并实现对细胞连续捕获后的原位培养. 将该芯片与卟啉可视阵列传感器系统结合, 经代谢特征分析可有效区分不同种类肿瘤细胞, 实现芯片细胞培养平台上的细胞代谢指纹快速可视化传感检测. 相似文献
75.
Rutherford backscattering and channeling spectrometry (RBS/C) are used to identify the crystalline quality (Xmin = 4.87%) Of an InN thin film as a function of depth, and make a non-destructive quantitative analysis of the structure, in order to analyze the tetragonal distortion of the InN thin film at the depth determined. 相似文献
76.
77.
Alfons G. Hoekstra Peter M. A. Sloot 《Particle & Particle Systems Characterization》1994,11(3):189-193
The coupled dipole method, as originally formulated by Purcell and Pennypacker [3], is a very powerful method to simulate the elastic light scattering from arbitrary particles. This method, however, has one major drawback: if the size of the particles grows, or if scattering from an ensemble of randomly oriented particles has to be simulated, the computational demands of the coupled dipole method soon become too high. This paper presents two new computational techniques to resolve this problem. First the coupled dipole method was implemented on a massively parallel computer. The parallel efficiency can be very close to 1, implying that the attained computational speed scales perfectly with the number of processors. Second, it is proposed to reduce the computational complexity of the coupled dipole method by including ideas from the so-called fast multipole methods (hierarchical algorithms) into the coupled dipole method. In this way calculation time can be decreased by orders of magnitude. 相似文献
78.
79.
To store ions for times up to several seconds with energies in the 10 eV/amu range a tabletop storage ring with a circumference of about 1 m will be constructed. The ions will be confined and guided by RF-multipoles. The first objective is the production of pure ground state beams of (multiply charged) ions. This will allow for elucidating the unknown rule of metastable ions in electron capture studies, which will be performed in a crossed beam experiment after extraction of the ion beam from the storage ring. In order to test the technique of ion storage by means of RF-multipoles a linear RF-octopole beam guide has been constructed. First results of highly charged ion injection and subsequent electron capture studies in the RF-octopole beam guide are presented for C4+ ions. 相似文献
80.
B. Hoekstra F. van Doveren J. M. Robertson 《Applied Physics A: Materials Science & Processing》1977,12(3):261-263
The magnetostriction constants of Y2.85La0.15Fe3.75Ga1.25O12 epilayers have been measured by observing the shift of the resonance line of a thin film which is stressed by three-point
bending. The result is λ111=−(0.75±0.15) × 10−6 and λ100=−(0.4±0.1) × 10−6 which is in agreement with the measurements on bulk single crystals. This result indicates that there is no growth induced
contribution to the magnetostriction in thin films of this garnet grown by liquid phase epitaxy. 相似文献