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71.
Martin Franc Jana Sobotníková Pavel Coufal Zuzana Bosáková 《Journal of separation science》2014,37(17):2278-2283
Fused‐silica capillary columns for high‐performance liquid chromatography with 320 and 250 μm inner diameter were prepared by slurry packing with 5 and 3 μm Nucleosil C18 stationary phase. Different types of mechanical and monolithic outlet frits were used and their influence on the resulting column performance was evaluated. Columns with quartz wool exhibited symmetrical peaks and low theoretical plate height, and the preparation time was short. The performance of monolithic frits varied based on type of monolith, length of the frit, and silanization procedure. The best frit performed similarly to the quartz wool ones, but the preparation took several hours. Their main advantage lies in the possibility of on‐column detection, because the detection window can be burnt immediately behind the frit. 相似文献
72.
73.
Although there exist a number of methods, such as NMR, X-ray, e.g., which explore the hydration of phospholipid bilayers,
the solvent relaxation (SR) method has the advantage of simple instrumentation, easy data treatment and possibility of measuring
fully hydrated samples. The main information gained from SR by the analysis of recorded “time-resolved emission spectra” (TRES)
is micro-viscosity and micro-polarity of the dye microenvironment. Based on these parameters, one can draw conclusions about
water structure in the bilayer. In this review, we focus on physical background of this method, on all the procedures that
are needed in order to obtain relevant parameters, and on the requirements on the fluorescence dyes. Furthermore, a few recent
applications (the effect of curvature, binding of antibacterial peptides and phase transition) illustrating the versatility
of this method are mentioned. Moreover, limitations and potential problems are discussed. 相似文献
74.
Shape effect in nanoparticle self-assembly 总被引:2,自引:0,他引:2
Jana NR 《Angewandte Chemie (International ed. in English)》2004,43(12):1536-1540
75.
Pancyclicity of Strong Products of Graphs 总被引:1,自引:0,他引:1
Daniel?KrálEmail author Jana?Maxová Pavel?Podbrdsky Robert??ámal 《Graphs and Combinatorics》2004,20(1):91-104
We prove that the strong product of graphs G1××Gn is pancyclic, in particular hamiltonian, for nc for any cln(25/12)+1/640.75 whenever all Gi are connected graphs with the maximum degree at most .This research was supported by KONTAKT ME 337 as a part of REU programme and in part by GACR 201/99/0242The author acknowledges partial support by NSF grant DMS-9900969 and by Institute for Theoretical Computer ScienceThe author acknowledges partial support by Institute for Theoretical Computer ScienceInstitute for Theoretical Computer Science is supported by Ministry of Education of Czech Republic as project LN00A056Final version received: August 6, 2003 相似文献
76.
Menard E Bilhaut L Zaumseil J Rogers JA 《Langmuir : the ACS journal of surfaces and colloids》2004,20(16):6871-6878
Nanotransfer printing represents an additive approach for patterning thin layers of solid materials with nanometer resolution. The surface chemistries, thin film deposition techniques, and stamp designs are all important for the proper operation of this method. This paper presents some details concerning processing procedures and other considerations needed for patterning two- and three-dimensional nanostructures with low density of defects and minimal distortions. 相似文献
77.
Friedrich MG Giebeta F Naumann R Knoll W Ataka K Heberle J Hrabakova J Murgida DH Hildebrandt P 《Chemical communications (Cambridge, England)》2004,(21):2376-2377
Membrane-bound cytochrome c oxidase was attached to an electrode via a His-tag linker and studied by surface enhanced resonance Raman spectroscopy, demonstrating intact redox site structures and electron transfer between the electrode and the immobilized enzyme. 相似文献
78.
Immunomagnetic separation and detection of Salmonella cells using newly designed carriers 总被引:1,自引:0,他引:1
Spanová A Rittich B Horák D Lenfeld J Prodelalová J Suciková J Strumcová S 《Journal of chromatography. A》2003,1005(1-2):215-221
A new method for simultaneous determination of alkoxyethanols (2-methoxyethanol, 2-ethoxyethanol, 2-isopropoxyethanol, and 2-butoxyethanol) by high-performance liquid chromatography (HPLC) with fluorescence detection has been developed. The alkoxyethanols and an internal standard (2-phenoxyethanol) were derivatized by treatment with 1-anthroylnitrile to give the anthroyl esters. The esterification was completed in 30 min in the presence of quinuclidine as base catalyst at room temperature. After stopping the reaction, an aliquot of the final solution was injected into the HPLC. The resulting anthroyl esters of the alkoxyethanols and the internal standard were separated on a C18 reversed-phase column with acetonitrile-water-acetic acid (65:35:0.1, v/v) as the mobile phase and detected fluorimetrically at excitation and emission wavelengths of 360 nm and 460 nm, respectively. The detection limits of the derivatives as alkoxyethanols at a signal-to-noise ratio of 3 were in the range of 1-3 pg per injection. The minimal amounts of alkoxyethanols derivatized in the reaction mixture for derivatization to determine the limits of detection were approximately 0.5 ng. This HPLC method was applied to the determination of some of alkoxyethanols in the air of the workplace where the thinner containing alkoxyethanols was used for painting. 相似文献
79.
Consider a special stable partition problem in which the player's preferences over sets to which she could belong are identical
with her preferences over the most attractive member of a set and in case of indifference the set of smaller cardinality is
preferred. If the preferences of all players over other (individual) players are strict, a strongly stable and a stable partition
always exists. However, if ties are present, we show that both the existence problems are NP-complete. These results are very
similar to what is known for the stable roommates problem.
Received: July 2000/Revised: October 2002
RID="*"
ID="*" This work was supported by the Slovak Agency for Science, contract #1/7465/20 “Combinatorial Structures and Complexity
of Algorithms”. 相似文献
80.
Fuzzification of the analytic hierarchy process (AHP) is of great interest to researchers since it is a frequently used method for coping with complex decision making problems. There have been many attempts to fuzzify the AHP. We focus particularly on the construction of fuzzy pairwise comparison matrices and on obtaining fuzzy weights of objects from them subsequently. We review the fuzzification of the geometric mean method for obtaining fuzzy weights of objects from fuzzy pairwise comparison matrices. We illustrate here the usefulness of the fuzzified AHP on a real-life problem of the evaluation of quality of scientific monographs in university environment. The benefits of the presented evaluation methodology and its suitability for quality assessment of R&D results in general are discussed. When the task of quality assessment in R&D is considered, an important role is played by peer-review evaluation. Evaluations provided by experts in the peer-review process have a high level of subjectivity and can be expected in a linguistic form. New decision-support methods (or adaptations of classic methods) well suited to deal with such inputs, to capture the consistency of experts’ preferences and to restrict the subjectivity to an acceptable level are necessary. A new consistency condition is therefore defined here to be used for expertly defined fuzzy pairwise comparison matrices. 相似文献