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31.
Stefan Spange Frank Simon Heidrun Schutz Andrea Schramm Heinz Winkelmann 《高分子科学杂志,A辑:纯化学与应用化学》2013,50(11):997-1006
Abstract The preparation of cationically active oligo-p-methoxystyrene-silica composites by cationic interfacial polymerization is described. In addition to the effective preparation of the interfacial initiator, p-methoxybenzylium-hydrogen sulfate-silica, and p-methoxybenzylium-trifluoroacetate-silica, a procedure to yield new kinds of composites is reported. The outstanding properties of the “living” oligo-p-methoxy-styryl-hydrogen sulfate-silica is demonstrated by means of zeta potential measurements, solid-state 13C-NMR spectroscopy, UV/Vis spectroscopy, and electron scanning microscopy. 相似文献
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We prove that the SLE
κ
trace in any simply connected domain G is continuous (except possibly near its endpoints) if κ < 8. We also prove an SLE analog of Makarov’s Theorem about the support of harmonic measure. 相似文献
35.
H. -P. Rentschler und B. Schramm 《Colloid and polymer science》1978,256(6):607
Ohne Zusammenfassung 相似文献
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G. Adam und B. Schramm 《Colloid and polymer science》1978,256(8):829
Ohne Zusammenfassung 相似文献
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The effects of 17-ethinylestradiol (EE), an endocrine disruptor, on zoo- and phytoplankton were studied in outdoor 230-L still-water microcosms. Cell density and biomass, diversity, and community composition were analyzed. Five microcosms were treated by controlled release for six weeks, three by direct application of EE. To investigate recovery, sampling was continued for four weeks after treatment. Most characteristics of the zooplankton were not unambiguously affected by EE. Only the relative density of copepods, especially of their larvae, decreased significantly after EE application. For phytoplankton, no unambiguous concentration- or toxodose-correlated effects on any biotic characteristics could be found. However, most properties of the phytoplankton deviated from those of controls, i.e. tended to be smaller (number of species per microcosm, biomass, cell density) or covered a wider range (diversity, evenness). PCA indicated a shift of species structure in the treated microcosms. This was supported by the species scores calculated by the principal response curve method, although the principal response curve itself showed no clear EE-correlated shifts. High variability within the biocenosis between microcosms and over time, probably because of disturbance of the ecosystem before starting of the test, might have superimposed EE-dependent effects.Abbreviations
c
dt
Canonical coefficient
- CRD
Controlled-release device
-
E
Shannon–Wiener index for evenness
- EC10
Effect concentration for 10% of maximum effect
- EC50
Effect concentration for 50% of maximum effect
- EE
17-Ethinylestradiol
-
H
Shannon–Wiener index for diversity
- LPDE
Low density polyethylene
- NOEC
No observed effect concentration
- PCA
Principal component analysis
- PRC
Principal response curve
- RDA
Redundancy analysis
- SD
Standard deviation 相似文献
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In this contribution, simple methods are presented for controlling a simulated moving bed (SMB) chromatographic process with standard PI (proportional integral) controllers. The first method represents a simple and model-free inferential control scheme which was motivated from common distillation column control. The SMB unit is equipped with UV detectors. The UV signals in the four separation zones of the unit are fixed by four corresponding PI controllers calculating the ratio of liquid and solid flow in the respective separation zone. In order to be able to adjust the product purity a second, model-based control scheme is proposed. It makes use of the nonlinear wave propagation phenomena in the apparatus. The controlled chromatographic unit is automatically working with minimum solvent consumption and maximum feed throughput--without any numerical optimization calculations. This control algorithm can therefore also be applied for fast optimization of SMB processes. 相似文献