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861.
862.
Natalia Bourguignon Carol M. Olmos Marina Sierra-Rodero Ana Peñaherrera Gustavo Rosero Pedro Pineda Karla Vizuete Carlos R. Arroyo Luis Cumbal Carlos Lasorsa Maximiliano S. Perez Betiana Lerner 《Journal of polymer science. Part A, Polymer chemistry》2018,56(21):1433-1442
This work describes a novel and cost-effective method of polydimethylsiloxane (PDMS) microchips fabrication by using a printing plate photopolymer called Flexcel as a master mold (Fmold). This method has demonstrated the ability to generate multiple devices from a single master, reaching a minimum channel size of 25 μm, structures height ranging from 53 to 1500 μm and achieving dimensions of 1270 × 2062 mm2, which are larger than those obtained by the known techniques to date. Scanning electron microscopy, atomic force microscopy, and profilometry techniques have been employed to characterize the Fmold and PDMS replicas. The results showed high replication fidelity of Fmold to the PDMS replica. Furthermore, it was proved the reusability of the Fmold. In our study, up to 50 PDMS replicas have been fabricated without apparent degradation of the mold. The feasibility of the resulting PDMS replica was effectively demonstrated using a microfluidic device for enhanced oil recovery analysis. © 2018 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2018 , 56, 1433–1442 相似文献
863.
A highly enantioselective organocatalytic oxindole addition to α,β-unsaturated aldehydes is reported. The reaction is catalyzed by simple and commercially available chiral secondary amines, affording the corresponding adducts with good yields and with moderate diastereoselectivities. 相似文献
864.
Pride groups, or groups given by presentations in whicheach defining relator involves at most two types of generators,include Coxeter groups, Artin groups, triangles of groups, andVinberg's groups defined by periodic paired relations. We showthat every non-spherical Pride group that is not a triangleof groups satisfies the Tits alternative. 相似文献
865.
866.
Anilines and ethyl vinyl ether can be used as precursors for a process that is the synthetic equivalent of the α-arylation of acetaldehyde enolate. The reaction manifests a high level of functional group compatibility, allowing the ready preparation of a number of synthetically valuable compounds. 相似文献
867.
Victor D. Didenko Natalia A. Rozhenko 《Mathematical Methods in the Applied Sciences》2014,37(15):2211-2217
A spectral problem for the Sturm–Liouville equation on the edges of an equilateral regular star‐tree with the Dirichlet boundary conditions at the pendant vertices and Kirchhoff and continuity conditions at the interior vertices is considered. The potential in the Sturm–Liouville equation is a real–valued square summable function, symmetrically distributed with respect to the middle point of any edge. If {λj}is a sequence of real numbers, necessary and sufficient conditions for {λj}to be the spectrum of the problem under consideration are established. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
868.
An electrochemical biosensor for the detection of DNA based a peptide nucleic acid (PNA) capture probe (CP) modified indium tin oxide electrode (ITO) is described in this report. After hybridization, a threading intercalator, N,N′-bis[(3-propyl)-imidazole]-1,4,5,8-naphthalene diimide (PIND) imidazole complexed with Ru(bpy)2Cl (PIND-Ru, bpy = 2,2′-bipyridine), was introduced to the biosensor. PIND-Ru selectively intercalated to double-stranded DNA (ds-DNA) and became immobilized on the biosensor surface. Voltammetric tests showed highly stable and reversible electrochemical oxidation/reduction processes and the peak currents can directly be utilized for DNA quantification. When the tests were conducted in an amine-containing medium, Tris-HCl buffer for example, a remarkable improvement in the voltammetric response and noticeable enhancements of voltammetric and amperometric sensitivities were observed due to the electrocatalytic activity of the [Ru(bpy)2Cl] redox moieties. Electrocatalytic current was observed when as little as 3.0 attomoles of DNA was present in the sample solution. 相似文献
869.
Xiangdong Meng Rihab Al‐Salman Jiupeng Zhao Prof. Natalia Borissenko Dr. Yao Li Prof. Frank Endres Prof. 《Angewandte Chemie (International ed. in English)》2009,48(15):2703-2707
A promising method for the production of germanium photonic crystals consists of electrodeposition of Ge from GeCl4‐containing ionic liquids inside templates of polystyrene colloidal crystals and subsequent removal of the template. This room‐temperature method gives rise to the fabrication of a three‐dimensional highly ordered macroporous germanium nanostructure (see picture; scale: 2 μm) as a prototype of a photonic crystal.
870.
Towards a nondestructive chemical characterization of biofilm matrix by Raman microscopy 总被引:2,自引:1,他引:1
Ivleva NP Wagner M Horn H Niessner R Haisch C 《Analytical and bioanalytical chemistry》2009,393(1):197-206
In this study, the applicability of Raman microscopy (RM) for nondestructive chemical analysis of biofilm matrix, including
microbial constituents and extracellular polymeric substances (EPS), has been assessed. The examination of a wide range of
reference samples such as biofilm-specific polysaccharides, proteins, microorganisms, and encapsulated bacteria revealed characteristic
frequency regions and specific marker bands for different biofilm constituents. Based on received data, the assignment of
Raman bands in spectra of multispecies biofilms was performed. The study of different multispecies biofilms showed that RM
can correlate various structural appearances within the biofilm to variations in their chemical composition and provide chemical
information about a complex biofilm matrix. The results of RM analysis of biofilms are in good agreement with data obtained
by confocal laser scanning microscopy (CLSM). Thus, RM is a promising tool for a label-free chemical characterization of different
biofilm constituents. Moreover, the combination of RM with CLSM analysis for the study of biofilms grown under different environmental
conditions can provide new insights into the complex structure/function correlations in biofilms. 相似文献