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51.
Bergner G Albert CR Schiller M Bringmann G Schirmeister T Dietzek B Niebling S Schlücker S Popp J 《The Analyst》2011,136(18):3686-3693
The introduction of carbon-deuterium (C-D) bonds into drug compounds by organic synthesis is a non-invasive labelling approach, which does not alter the chemical and physiological properties of the drug itself. C-deuterated drugs exhibit characteristic vibrational signatures in the C-D stretching region around 2100-2300 cm(-1), which avoids spectral interference with contributions from a complex biological environment. In this paper, the quantitative detection of C-deuterated drugs by Raman microspectroscopy and single-band CARS microscopy is examined. Concentration-dependent studies on drugs with aliphatic and aromatic C-D moieties were performed in a two-channel microfluidic chip, using the corresponding non-deuterated (C-H) isotopologues as an internal reference. 相似文献
52.
By this article we conclude the construction of all primitive ( v, k,λ ) symmetric designs with v < 2500 , up to a few unsolved cases. Complementary to the designs with prime power number of points published previously, here we give 55 primitive symmetric designs with v ≠ p m , p prime and m positive integer, together with the analysis of their full automorphism groups. The research involves programming and wide‐range computations. We make use of the software package GAP and the library of primitive groups which it contains. © 2011 Wiley Periodicals, Inc. J Combin Designs 19:463‐474, 2011 相似文献
53.
Jasmina M. Dimitrić Marković Dragan S. Veselinović Jelisaveta M. Baranac Tanja P. Brdarić 《光谱学快报》2013,46(3):104-115
Complexation of aluminum (III) with cyanidin, a natural anthocyanidin molecule, has been investigated in methanol and buffered solutions of pH 3.0 and 4.0. Electronic absorption spectroscopy was performed to characterize the stoichiometry and stability of the complexes formed. In investigated solvents, aluminum bonded moderately to cyanidin requiring large mole ratios of the components (up to 200) for the access of complexation. Molar ratio plots showed the formation of only one complex with stoichiometry aluminum (III):cyanidin of 1∶1 in both investigated media. Semiempirical calculations, performed in the Austin Model 1 parameterization, enabled the determination of the structural features of free compounds as well as complex structural modifications caused by chelation of Al(III). 相似文献
54.
55.
Hawtin P Hardern I Wittig R Mollenhauer J Poustka A Salowsky R Wulff T Rizzo C Wilson B 《Electrophoresis》2005,26(19):3674-3681
On-chip electrophoresis can provide size separations of nucleic acids and proteins similar to more traditional slab gel electrophoresis. Lab-on-a-chip (LoaC) systems utilize on-chip electrophoresis in conjunction with sizing calibration, sensitive detection schemes, and sophisticated data analysis to achieve rapid analysis times (<120 s). This work describes the utility of LoaC systems to enable and augment systems biology investigations. RNA quality, as assessed by an RNA integrity number score, is compared to existing quality control (QC) measurements. High-throughput DNA analysis of multiplex PCR samples is used to stratify gene sets for disease discovery. Finally, the applicability of a high-throughput LoaC system for assessing protein purification is demonstrated. The improvements in workflow processes, speed of analysis, data accuracy and reproducibility, and automated data analysis are illustrated. 相似文献
56.
Kappaun S Sović T Stelzer F Pogantsch A Zojer E Slugovc C 《Organic & biomolecular chemistry》2006,4(8):1503-1511
Three 5,7-pi-extended 8-benzyloxyquinolines, namely 5,7-diphenyl-, 5,7-bis(biphenyl-4-yl)- and 5,7-bis(4-dibenzothiophenyl)-8-benzyloxyquinoline were prepared and investigated as fluorescent pH-probes in nonaqueous solution. Absorption and photoluminescence spectra of the introduced compounds also including the starting material 8-benzyloxy-5,7-dibromoquinoline as well as their N-protonated counterparts were recorded and the results were rationalized by quantum-chemical calculations. A pronounced red shift of the emission occurred upon protonation of the non halogenated derivatives, while the dibromo-derivative is hardly emissive and is virtually not protonated under the conditions used. The diphenyl- and the bis(biphenyl)-derivative especially show promising photoluminescence quantum yields both in the parent and the protonated state making them candidates for the active component in pH sensing applications. 相似文献
57.
[reaction: see text] The first total synthesis of an N,C-coupled naphthylisoquinoline alkaloid-ancisheynine-was achieved by condensing a monocyclic diketone or the respective benzopyrylium salt with an aminonaphthalene. The presence of a rotationally hindered axis in ancisheynine was demonstrated by resolution of its two atropo-enantiomers by HPLC on a chiral phase with LC-CD coupling. The assignment of their axial configurations succeeded by quantum chemical CD calculations. 相似文献
58.
59.
Ramesh-Babu Adusumalli Rejin Raghavan Rudy Ghisleni Tanja Zimmermann Johann Michler 《Applied Physics A: Materials Science & Processing》2010,100(2):447-452
The deformation and failure of the secondary cell wall of Spruce wood was studied by in-situ SEM compression of micropillars
machined by the focused ion beam technique. The cell wall exhibited yield strength values of approximately 160 MPa and large
scale plasticity. High resolution SEM imaging post compression revealed bulging of the pillars followed by shear failure.
With additional aid of cross-sectional analysis of the micropillars post compression, a model for deformation and failure
mechanism of the cell wall has been proposed. The cell wall consists of oriented cellulose microfibrils with high aspect ratio
embedded in a hemicellulose-lignin matrix. The deformation of the secondary wall occurs by asymmetric out of plane bulging
because of buckling of the microfibrils. Failure of the cell wall following the deformation occurs by the formation of a shear
or kink band. 相似文献
60.
A subset S of vertices of a graph G is a secure set if |N [X] ∩ S| ≥ |N [X] ? S| holds for any subset X of S, where N [X] denotes the closed neighborhood of X. The minimum cardinality s(G) of a secure set in G is called the security number of G. We investigate the security number of lexicographic product graphs by defining a new concept of tightly-securable graphs. In particular we derive several exact results for different families of graphs which yield some general results. 相似文献