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31.
32.
E. Ziegler Th. Wimmer Heidrun Mittebach 《Monatshefte für Chemie / Chemical Monthly》1968,99(5):2128-2133
Zusammenfassung Aus Mono-und Dihalogen-essigsäuren bilden sich mitSchiff-schen Basen in Dimethylformamid (DMF) und POCl3 (bzw. POBr3) über labile Addukte -Lactame. Analog reagieren -Chlor-und -Brom-propionsäure.
The reaction of -chloro and -bromo acetic or propionic acids withSchiff bases inDMF in the presence of POCl3 or POBr3 yields -lactames via unstable adducts.相似文献
33.
Keul HA Ryu HJ Möller M Bockstaller MR 《Physical chemistry chemical physics : PCCP》2011,13(30):13572-13578
The relevance of anion structure on the shape regulating effect of 3-ethyl-1-methylimidazolium-based ionic liquids during the seed-induced growth of gold nanocrystals is evaluated for the particular case of lactate, acetate, methylsulfate, ethylsulfate and tosylsulfonate anion systems. Carboxylate-based anions (lactate and acetate) are found to inhibit the reduction of the gold precursor salt presumably due to the deprotonation of the reducing agent ascorbic acid. The formation of non-uniform, 'head-tail'-type anisotropic particle structures is observed in both methyl- and ethylsulfate anion systems whereas rapid precipitation is observed in the case of tosylsulfonate anions. The particular efficiency of the ethylsulfate solvent system in promoting shape anisotropic growth is interpreted to be a consequence of both reduced anion/cation interactions that act to support the coordination of imidazolium to the metal surface and the enhanced capacity of anions to participate in the particle stabilization process. 相似文献
34.
Summary Increasing amounts of large climate data require new analysis techniques. The area of data mining investigates new paradigms
and methods including factors like scalability, flexibility and problem abstraction for large data sets. The field of visual
data mining in particular offers valuable methods for analyzing large amounts of data intuitively. In this paper we describe
our approach of integrating cluster analysis and visualization methods for the exploration of climate data. We integrated
cluster algorithms, appropriate visualization techniques and sophisticated interaction paradigms into a general framework. 相似文献
35.
A simple method for the extraction of carotenoid pigments from frozen wet cells of red yeasts (Basidiomycota) and their analysis by reversed-phase HPLC using a C(18) column and a water/acetone solvent system is described. Typical red yeast carotenoids belonging to an oxidative series from the monocyclic gamma-carotene to 2-hydroxytorularhodin and from the bicyclic beta-carotene to astaxanthin were separated. Pigment identity was confirmed by LC-atmospheric pressure chemical ionisation (APCI) mass spectrometry using similar chromatographic conditions. 相似文献
36.
Chrysoxanthone, an unusual heterodimer of blennolide A and 2-hydroxychrysophanol linked through a diaryl ether bridge, was isolated from mycelia of the ascomycete IBWF11-95A grown in submerged culture. Its structure was elucidated by two-dimensional NMR spectroscopy. The metabolite shows antibacterial activity against different species with MIC values between 2.5 and 20 μg/mL while also inhibiting the growth of several fungi. 相似文献
37.
38.
Keul HA Möller M Bockstaller MR 《Langmuir : the ACS journal of surfaces and colloids》2007,23(20):10307-10315
Single-crystalline gold nanorods synthesized by the Ag(I)-mediated seeded-growth method (see: El-Sayed, M. A.; Nikoobakht, B. Chem. Mater. 2003, 15, 1957) were used as seeds for the preferential overgrowth of gold on particular crystallographic facets by systematic variation of the conditions during overgrowth. The results support previous reports about the relevance of the cationic surfactant cetyltrimethylammonium bromide (CTAB) and Ag(I) in stabilizing anisotropic particle shapes and demonstrate that the regulation of the amount of ascorbic acid facilitates the preferential overgrowth of {111} crystal facets to form Xi-type particle shapes. Interestingly, secondary overgrowth is found to inevitably result in a loss of particle shape anisotropy. A mechanism based on surface reconstruction is proposed to rationalize the "shape-reversal" that is generally observed in the nanorod growth process, that is, the initial increase and subsequent decrease of particle anisotropy with increasing reaction time. High-resolution electron microscopy analysis of gold nanorods reveals clear evidence for (1 x 2) missing row surface reconstruction of high energetic {110} facets that form during the initial phase during particle growth. 相似文献
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40.
Martin Rieger Christian Kochleus Dana Teschner Daniela Rascher Ann Kristin Barton Arie Geerlof Elisabeth Kremmer Michael Schmid Anton Hartmann Heidrun Gehlen 《Analytical and bioanalytical chemistry》2014,406(22):5507-5512
In human medicine, procalcitonin (PCT) is a very common and well-established biomarker for sepsis. Even though sepsis is also a leading cause of death in foals and adult horses, up to now, no data about the role of equine PCT in septic horses has been available. Based on monoclonal antibodies targeted against human PCT, we report here the development of a sandwich ELISA for the quantification of equine PCT in equine plasma samples. The ELISA was characterized for intra- and interassay variance and a working range from 25 to 1,000 ng mL?1 was defined as within this range; both intra- and interassay variances were below 15 %. The target recovery ranged between 73 and 106 %. The ELISA was used to determine the equine PCT concentration in 24 healthy and 5 septic horses to show the potential for clinical evaluation of equine PCT. Significantly different (P?=?0.0006) mean equine PCT concentrations were found for the healthy control group and the sepsis group (47 and 8,450 ng mL?1). 相似文献