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111.
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
112.
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
113.
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
114.
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
115.
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
116.
Krishna Dan Priya Rajdev Jolly Deb Siddhartha S. Jana Suhrit Ghosh 《Journal of polymer science. Part A, Polymer chemistry》2013,51(22):4932-4943
Synthesis of a library of amphiphilic random copolymers from a single reactive pre‐polymer and their self‐assembly is reported. Post‐polymerization modifications of the parent polymer containing pendant N‐hydroxy succinimide (NHS) ester groups with various oligooxyethylene (OE) amines produce amphiphilic random copolymers with same degree of polymerization and equal extent of randomness. 1H‐NMR and FT‐IR data indicate quantitative substitution in all cases. The critical aggregation concentration (CAC) for all the polymers is estimated to be in the range of 10?5 M. Stability of these nano‐aggregates is studied by photoluminescence using time dependent F—rster Resonance Energy Transfer (FRET) between co‐encapsulated lipophilic dyes namely DiO and DiI in the hydrophobic pocket of the aggregates. These studies suggest remarkably high stability for all systems. However those with shorter hydrophilic pendant chains are found to be even more robust. Morphology is examined by high resolution transmission electron microscopy (HRTEM) which reveals multi‐micellar clusters and vesicles for polymers containing short and longer OE segments, respectively. Encapsulation efficacy is tested with both hydrophobic and hydrophilic guest molecules. All of them can encapsulate hydrophobic guest pyrene while a hydrophilic dye Calcein can be sequestered only in vesicle forming polymers. Lower critical solution temperature (LCST) is exhibited by only one polymer that contains the shortest OE chains. All polymers exhibit excellent cell viability as determined by MTT assay. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2013 , 51, 4932–4943 相似文献
117.
118.
Jana Jurečková 《Statistics & probability letters》2010,80(23-24):1940-1946
The finite-sample distributions of the regression quantile and of the extreme regression quantile are derived for a broad class of distributions of the model errors, even for the non-i.i.d case. The distributions are analogous to the corresponding distributions in the location model; this again confirms that the regression quantile is a straightforward extension of the sample quantile. As an application, the tail behavior of the regression quantile is studied. 相似文献
119.
Kalyanmoy Jana Somnath Das Tithi Maity Maidul Hossain Subhas Chandra Debnath 《Journal of Coordination Chemistry》2018,71(10):1497-1509
A new Co(II) complex of general formula [Co(L)2] has been synthesized from a NNO tridentate Schiff base ligand, 2-[(piperidin-2-ylmethylimino)-methyl]-phenol (L). The title complex is characterized by elemental, spectroscopic, antibacterial, and single crystal X-ray structural studies. X-Ray crystallography reveals that the complex shows a distorted octahedral geometry around the Co(II) ion. The complex was tested against several bacteria and shows good antibacterial activities against almost all of the bacteria. The interactions of the title complex with calf thymus deoxyribonucleic acid (CT-DNA) have been investigated by electronic absorption and fluorescence spectroscopy, showing that the complex interacts with CT-DNA via partial intercalation. Thermogravimetric analysis (TGA) of the complex has also been reported and the result shows that the complex is thermally stable up to 134 °C. 相似文献
120.
Direct conversion of alkyl trimethylsilyl ethers to carbonyl compounds is accomplished using PFC in dichloromethane at room temperature. For a similar oxidation of t-butyldimethylsilyl ethers the PCC-n-Bu4NF combination may be employed. 相似文献