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61.
Bu HB Götz G Reinold E Vogt A Azumi R Segura JL Bäuerle P 《Chemical communications (Cambridge, England)》2012,48(21):2677-2679
A PEDOT-based conductive copolymer soluble in organic solvents was synthesized electrochemically using dihexyl-EDOT and azidomethyl-EDOT as monomers and was successfully post-functionalized by "click"-cycloaddition reaction with a functionalized terminal alkyne under mild heterogeneous conditions. 相似文献
62.
de Wijn AS Riesco N Jackson G Trusler JP Vesovic V 《The Journal of chemical physics》2012,136(7):074514
New expressions for the viscosity of liquid mixtures, consisting of chain-like molecules, are derived by means of Enskog-type analysis. The molecules of the fluid are modelled as chains of equally sized, tangentially joined, and rigid spheres. It is assumed that the collision dynamics in such a fluid can be approximated by instantaneous collisions. We determine the molecular size parameters from the viscosity of each pure species and show how the different effective parameters can be evaluated by extending the Vesovic-Wakeham (VW) method. We propose and implement a number of thermodynamically consistent mixing rules, taking advantage of SAFT-type analysis, in order to develop the VW method for chain molecules. The predictions of the VW-chain model have been compared in the first instance with experimental viscosity data for octane-dodecane and methane-decane mixtures, thus, illustrating that the resulting VW-chain model is capable of accurately representing the viscosity of real liquid mixtures. 相似文献
63.
Gen Tanaka Ikuhiko Nakase Yasunori Fukuda Ryo Masuda Shinya Oishi Kazuya Shimura Yoshimasa Kawaguchi Tomoka Takatani-Nakase Ülo Langel Astrid Gräslund Katsuya Okawa Masao Matsuoka Nobutaka Fujii Yasumaru Hatanaka Shiroh Futaki 《Chemistry & biology》2012,19(11):1437-1446
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64.
Dr. Suman Kumar Maity Paul Stahl Dr. Astrid Hensel Prof. Dr. Shirley Knauer Dr. Christoph Hirschhäuser Prof. Dr. Carsten Schmuck 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(14):3010-3015
Tumor-targeted drug delivery is highly important for improving chemotherapy, as it reduces the dose of cytotoxic agents and minimizes the death of healthy tissues. Towards this goal, a conjugate was synthesized of gossypol and a MCF-7 cancer cell specific CPP (cell penetrating peptide), thus providing a selective drug delivery system. Utilizing the aldehyde moiety of gossypol, the tumor homing CPP RLYMRYYSPTTRRYG was attached through a semi-labile imine linker, which was cleaved in a traceless fashion under aqueous conditions and had a half-life of approximately 10 hours. The conjugate killed MCF-7 cells to a significantly greater extent than HeLa cells or healthy fibroblasts. 相似文献
65.
Astrid Baumann 《Aequationes Mathematicae》2003,65(3):201-235
Summary. Let $\widehat{\widehat T}_n$ and $\overline U_n$ denote the modified Chebyshev polynomials defined by $\widehat{\widehat T}_n (x) = {T_{2n + 1} \left(\sqrt{x + 3 \over 4} \right) \over \sqrt{x + 3 \over 4}}, \quad \overline U_{n}(x) = U_{n} \left({x + 1 \over 2}\right) \qquad (n \in \mathbb{N}_{0},\ x \in \mathbb{R}).$ For all $n \in \mathbb{N}_{0}$ define $\widehat{\widehat T}_{-(n + 1)} = \widehat{\widehat T}_n$ and $\overline U_{-(n + 2)} = - \overline U_n$, furthermore $\overline U_{-1} = 0$. In this paper, summation formulae for sums of type $\sum\limits^{+\infty}_{k = -\infty} \mathbf a_{\mathbf k}(\nu; x)$ are given, where
$\bigl(\mathbf a_{\mathbf k}(\nu; x)\bigr)^{-1} = (-1)^k \cdot \Bigl( x \cdot \widehat{\widehat T}_{\left[k + 1 \over 2\right] - 1} (\nu) +\widehat{\widehat T}_{\left[k + 1 \over 2\right]}(\nu)\Bigr) \cdot \Bigl(x \cdot \overline U_{\left[k \over 2\right] - 1} (\nu) + \overline U_{\left[k \over 2\right]} (\nu)\Bigr)$ with real constants $ x, \nu $. The above sums will turn out to be telescope sums. They appear in connection with projective geometry. The directed euclidean measures of the line segments of a projective scale form a sequence of type $(\mathbf a_{\mathbf k} (\nu;x))_{k \in \mathbb{Z}}$ where $ \nu $ is the cross-ratio of the scale, and x is the ratio of two consecutive line segments once chosen. In case of hyperbolic $(\nu \in \mathbb{R} \setminus] - 3,1[)$ and parabolic $\nu = -3$ scales, the formula $\sum\limits^{+\infty}_{k = -\infty} \mathbf a_{\mathbf k} (\nu; x) = {\frac{1}{x - q_{{+}\atop(-)}}} - {\frac{1}{x - q_{{-}\atop(+)}}} \eqno (1)$ holds for $\nu > 1$ (resp. $\nu \leq - 3$), unless the scale is geometric, that is unless $x = q_+$ or
$x = q_-$. By $q_{\pm} = {-(\nu + 1) \pm \sqrt{(\nu - 1)(\nu + 3)} \over 2}$ we denote the quotient of the associated geometric sequence.
相似文献
66.
Astrid Ollech 《International Journal of Theoretical Physics》1995,34(8):1647-1652
The problem I consider originates from Dörfler, who found a construction to assign an Orthocomplemented latticeH(G) to a graphG. By Dörfler it is known that for every finite Orthocomplemented latticeL there exists a graphG such thatH(G)=L. Unfortunately, we can find more than one graphG with this property, i.e., orthocomplemented lattices which belong to different graphs can be isomorphic. I show some conditions under which two graphs have the same orthocomplemented lattice. 相似文献
67.
68.
Astrid Lambrecht 《Physik in unserer Zeit》1997,28(2):88-88
Die Nachricht von den ersten Realisierungen von Bose-Einstein-Kondensaten aus schwach wechselwirkenden Atomen im Sommer 1995 [1,2] (siehe auch Physik in unserer Zeit, 27, 200 (5/1996)) zog eine Welle neuer Forschungsaktivitäten nach sich. Wolfgang Ketterle vom Massachusetts Institute of Technology, MIT, und Kollegen gelang es kürzlich, zwei Bose-Einstein-Kondensate zur Interferenz zu bringen [3]. 相似文献
69.
Uwe Kempin Lothar Hennig Dietmar Knoll Peter Welzel Dietrich Müller Astrid Markus Jean van Heijenoort 《Tetrahedron》1997,53(52):1594-17690
Moenomycin A (18) on reaction with the diazonium salt derived from bifunctional (protected) 15 yields the coupling product 19 which on reduction is converted into the moenomycin thiol derivative 21. Thiol 21 has been used to prepare selectively moenomycin dansyl and biotin adducts 26 and 28, respectively. This work was performed with the aim to use moenomycin as a tool for studies of the transglycosylation step in peptidoglycan biosynthesis. 相似文献
70.
Kari Dahl Astrid Hald Poul J?rgensen Ivar Martinsen Yngvar Thomassen 《Fresenius' Journal of Analytical Chemistry》1990,338(4):526-529
Summary Studies have been made of both short and long term stability of trace elements in lyophilized human body fluid reference materials, as well as the stability of mercury in reconstituted urine solutions. No detectable concentration changes for mercury, lead and aluminium occurred during the 5-year period. There are large differences in the amounts of mercury loss among different reconstituted materials. Addition of traces of gold to the solutions minimized the mercury loss and increased the useable time of the reconstituted material from hours to 8 days. A certification process based on direct determinations by reference laboratories and by comparison against master lots of the same material and against similar certified reference materials is presented. Values for calcium, copper and mercury obtained from reference laboratories and using the data transfer principle have been assigned in new batches of urine and serum. 相似文献