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排序方式: 共有127条查询结果,搜索用时 15 毫秒
1.
Kokol Vanja Vivod Vera Peršin Zdenka Čolić Miodrag Kolar Matjaž 《Cellulose (London, England)》2021,28(10):6545-6565
Cellulose - Bio-based, renewable and biodegradable products with multifunctional properties are also becoming basic trends in the textile sector. In this frame, cellulose nanofibrils (CNFs) have... 相似文献
2.
Miodrag Sokić 《Israel Journal of Mathematics》2013,194(2):609-640
We introduce the class COU S of finite ultrametric spaces with distances in the set S and with two additional linear orderings. We also introduce the class EOP of finite posets with two additional linear orderings. In this paper, we prove that COU S and EOP are Ramsey classes. In addition, we give an application of our results to calculus of universal minimal flows. 相似文献
3.
Steva Lević Nina Obradović Vladimir Pavlović Bojana Isailović Ivana Kostić Miodrag Mitrić Branko Bugarski Viktor Nedović 《Journal of Thermal Analysis and Calorimetry》2014,118(2):661-668
In this study, polyvinyl alcohol (PVA) nanofibers with ethyl vanillin as an active compound were prepared using electrospinning technique. The final products of electrospinning process were in the form of nanofibers films. PVA/ethyl vanillin nanofibers, having fibers diameters in the range 100–1700 nm, were successfully electrospun from ethanol/water mixture of PVA and ethyl vanillin. The effects of immobilization process on ethyl vanillin thermal properties were investigated by differential scanning calorimetry (DSC). The results of DSC showed significant influence of immobilization process on thermal properties of ethyl vanillin. It was noticed that melting point of immobilized ethyl vanillin was lower (~55 °C) compared to free flavor (~77 °C). Our results showed that films based on PVA/ethyl vanillin nanofibers are mechanically stable. 相似文献
4.
Higher-order methods for the simultaneous inclusion of complex zeros of algebraic polynomials are presented in parallel (total-step)
and serial (single-step) versions. If the multiplicities of each zeros are given in advance, the proposed methods can be extended
for multiple zeros using appropriate corrections. These methods are constructed on the basis of the zero-relation of Gargantini’s
type, the inclusion isotonicity property and suitable corrections that appear in two-point methods of the fourth order for
solving nonlinear equations. It is proved that the order of convergence of the proposed methods is at least six. The computational
efficiency of the new methods is very high since the acceleration of convergence order from 3 (basic methods) to 6 (new methods)
is attained using only n polynomial evaluations per iteration. Computational efficiency of the considered methods is studied in detail and two numerical
examples are given to demonstrate the convergence behavior of the proposed methods. 相似文献
5.
Using a fixed point relation of the square-root type and the basic fourth-order method, improved methods of fifth and sixth order for the simultaneous determination of simple zeros of a polynomial are obtained. An increase in convergence is achieved without additional numerical operations, which points to high computational efficiency of the accelerated methods. The main aim of this work is the convergence analysis of improved simultaneous methods given under computationally verifiable initial conditions in the spirit of Smale’s point estimation theory. 相似文献
6.
We presented new two-point methods for the simultaneous approximation of all n simple (real or complex) zeros of a polynomial of degree n. We proved that the R-order of convergence of the total-step version is three. Moreover, computationally verifiable initial conditions that guarantee the convergence of one of the proposed methods are stated. These conditions are stated in the spirit of Smale’s point estimation theory; they depend only on available data, the polynomial coefficients, polynomial degree n and initial approximations \(x_{1}^{(0)},\ldots ,x_{n}^{(0)}\) , which is of practical importance. Using the Gauss-Seidel approach we state the corresponding single-step version and consequently its prove that the lower bound of its R-order of convergence is at least 2 + y n > 3, where y n ∈ (1, 2) is the unique positive root of the equation y n ? y ? 2 = 0. Two numerical examples are given to demonstrate the convergence behavior of the considered methods, including global convergence. 相似文献
7.
Miodrag ?ivkovi? 《Linear algebra and its applications》2006,414(1):310-346
Denote by An the set of square (0, 1) matrices of order n. The set An, n ? 8, is partitioned into row/column permutation equivalence classes enabling derivation of various facts by simple counting. For example, the number of regular (0, 1) matrices of order 8 is 10160459763342013440. Let Dn, Sn denote the set of absolute determinant values and Smith normal forms of matrices from An. Denote by an the smallest integer not in Dn. The sets D9 and S9 are obtained; especially, a9 = 103. The lower bounds for an, 10 ? n ? 19 (exceeding the known lower bound an ? 2fn − 1, where fn is nth Fibonacci number) are obtained. Row/permutation equivalence classes of An correspond to bipartite graphs with n black and n white vertices, and so the other applications of the classification are possible. 相似文献
8.
Miodrag M. Spalević 《Numerical Algorithms》2007,46(3):253-264
We have recently proposed a very simple numerical method for constructing the averaged Gaussian quadrature formulas. These
formulas exist in many more cases than the real positive Gauss–Kronrod formulas. In this note we try to answer whether the
averaged Gaussian formulas are an adequate alternative to the corresponding Gauss–Kronrod quadrature formulas, to estimate
the remainder term of a Gaussian rule. 相似文献
9.
Correlated atomic force microscopy and fluorescence lifetime imaging of live bacterial cells 总被引:3,自引:0,他引:3
Micic M Hu D Suh YD Newton G Romine M Lu HP 《Colloids and surfaces. B, Biointerfaces》2004,34(4):205-212
We report on imaging living bacterial cells by using a correlated tapping-mode atomic force microscopy (AFM) and confocal fluorescence lifetime imaging microscopy (FLIM). For optimal imaging of Gram-negative Shewanella oneidensis MR-1 cells, we explored different methods of bacterial sample preparation, such as spreading the cells on poly-L-lysine coated surfaces or agarose gel coated surfaces. We have found that the agarose gel containing 99% ammonium acetate buffer can provide sufficient local aqueous environment for single bacterial cells. Furthermore, the cell surface topography can be characterized by tapping-mode in-air AFM imaging for the single bacterial cells that are partially embedded. Using in-air rather than under-water AFM imaging of the living cells significantly enhanced the contrast and signal-to-noise ratio of the AFM images. Near-field AFM-tip-enhanced fluorescence lifetime imaging (AFM-FLIM) holds high promise on obtaining fluorescence images beyond optical diffraction limited spatial resolution. We have previously demonstrated near-field AFM-FLIM imaging of polymer beads beyond diffraction limited spatial resolution. Here, as the first step of applying AFM-FLIM on imaging bacterial living cells, we demonstrated a correlated and consecutive AFM topographic imaging, fluorescence intensity imaging, and FLIM imaging of living bacterial cells to characterize cell polarity. 相似文献
10.