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排序方式: 共有476条查询结果,搜索用时 15 毫秒
91.
Mathematical Programming - The purpose of this paper is to characterize the weak efficient solutions, the efficient solutions, and the isolated efficient solutions of a given vector optimization... 相似文献
92.
Konstantin Pankrashkin Svetlana Roganova Nader Yeganefar 《Integral Equations and Operator Theory》2011,71(2):199-223
We study Laplace-type operators on hybrid manifolds, i.e., on configurations consisting of closed two-dimensional manifolds and one-dimensional segments. Such an operator can be constructed by using the Laplace–Beltrami operators on each component with some boundary conditions at the points of gluing. The large spectral parameter expansion of the trace of the second power of the resolvent is obtained. Some questions of the inverse spectral theory are addressed. 相似文献
93.
Samireh Esmaeili Samadizadeh Marjaneh Khaleghian Mehrnoosh Shiraz Nader Zabarjad 《Russian Journal of Physical Chemistry A, Focus on Chemistry》2020,94(4):778-788
Russian Journal of Physical Chemistry A - In the current study, the adsorption properties of the molecule (4E,6E)-4-(4-hydroxyphenyldiazenyl)-N-((furan-2-yl)methylene)benzenamine (AZO) on... 相似文献
94.
The solid‐solid reactions of some electron‐donors with sulfanilic acid in the presence of solid sodium nitrite afford azo dyes by self‐catalyzed diazotization of sulfanilic acid (2) under solvent‐free conditions with moderate yields. Also the reactions of some electron‐donors with diazotization of o‐nitroaniline (5), m‐nitroaniline (6) and p‐nitroaniline (7) in the presence of solid sodium nitrite catalyzed by p‐toluenesulfonic acid (PTSA) afford azo dyes under solvent‐free conditions in good yields. This new method totally avoids the use of acids, alkalies, and toxic and/or expensive solvents in diazotization and diazo coupling reactions. 相似文献
95.
Pyrosequencing is a relatively recent method for sequencing short stretches of DNA. Because both Pyrosequencing and Sanger dideoxy sequencing were recently used to characterize and validate DNA molecular barcodes in a large yeast gene-deletion project, a meta-analysis of those data allow an excellent and timely opportunity for evaluating Pyrosequencing against the current gold standard, Sanger dideoxy sequencing. Starting with yeast genomic DNA, parallel PCR amplification methods were used to prepared 4747 short barcode-containing constructs from 6000 Saccharomyces cerevisiae gene-deletion strains. Pyrosequencing was optimized for average read lengths of 25-30 bases, which included in each case a 20-mer barcode sequence. Results were compared with sequence data obtained by the standard Sanger dideoxy chain termination method. In most cases, sequences obtained by Pyrosequencing and Sanger dideoxy sequencing were of comparable accuracy, and the overall rate of failure was similar. The DNA in the barcodes is derived from synthetic oligonucleotide sequences that were inserted into yeast-deletion-strain genomic DNA by homologous recombination and represents the most significant amount of DNA from a synthetic source that has been sequenced to date. Although more automation and quality control measures are needed, Pyrosequencing was shown to be a fast and convenient method for determining short stretches of DNA sequence. 相似文献
96.
Nader?MasmoudiEmail author Frédéric?Rousset 《Archive for Rational Mechanics and Analysis》2012,203(2):529-575
We prove that there exists an interval of time which is uniform in the vanishing viscosity limit and for which the Navier–Stokes
equation with the Navier boundary condition has a strong solution. This solution is uniformly bounded in a conormal Sobolev
space and has only one normal derivative bounded in L
∞. This allows us to obtain the vanishing viscosity limit to the incompressible Euler system from a strong compactness argument. 相似文献
97.
98.
A simple and efficient synthesis for the preparation of unusual charge‐separated pyridinium (thio)barbiturate zwitterion derivatives was achieved via a one‐pot reaction of (thio)barbituric acid derivatives and 2‐pyridinecarbaldehyde under solvent‐free condition and also in methanol under refluxing. The structure of the compounds was confirmed by 1H NMR, 13C NMR, FT‐IR, mass and X‐ray analysis. The mechanism of the formation is discussed. Instead, no related pyridinium zwitterion was afforded from the reaction between dimedone and 2‐pyridinecarbaldehyde under the same conditions and its xanthene derivative was obtained. 相似文献
99.
Using the method of multiple scales, an extensive frequency response and subharmonic resonance analysis of the equations of
motion governing the nonlinear flexural vibrations of piezoelectrically actuated microcantilevers is performed. Such comprehensive
understanding of the nonlinear response and subharmonics analysis of these microcantilevers is, indeed, justified by the applications
of piezoelectrically actuated microcantilevers that are increasingly becoming popular in many science and engineering areas
including scanning force microscopy, biosensors, and microactuators. Along this line, the method of multiple scales is used
to derive the 2× and 3× subharmonic resonances appearing in nonlinear flexural vibrations of a piezoelectrically actuated
microcantilever. An experimental examination is performed in order to verify the analytical results. The analytical and experimental
results yield the same system response for the fundamental frequency. In addition, the experimental results demonstrate the
presence of subharmonic resonances that are supported by numerical simulations of the equations of motion. The experimental
mode shapes of these subharmonic frequencies are also measured and compared with fundamental frequency. 相似文献
100.