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排序方式: 共有219条查询结果,搜索用时 15 毫秒
91.
Nina Munkholt Jakobsen Michael Sørensen 《Stochastic Processes and their Applications》2019,129(9):3282-3318
Asymptotic theory for approximate martingale estimating functions is generalised to diffusions with finite-activity jumps, when the sampling frequency and terminal sampling time go to infinity. Rate-optimality and efficiency are of particular concern. Under mild assumptions, it is shown that estimators of drift, diffusion, and jump parameters are consistent and asymptotically normal, as well as rate-optimal for the drift and jump parameters. Additional conditions are derived, which ensure rate-optimality for the diffusion parameter as well as efficiency for all parameters. The findings indicate a potentially fruitful direction for the further development of estimation for jump–diffusions. 相似文献
92.
93.
For modeling multi-phase where the dispersed phase plays a major role in determining the flow structure and inter phase transfer quantities, the size distribution of the bubbles has to be considered. This can be done by extension of the mass balance equation to a population balance equation. In this work, a least squares spectral method is tested for predicting the evolution of the dispersed phase in a vertical two-phase bubbly flow. The least squares spectral method consists in minimizing the L2 norm of the residual over the simulation domain. The results are compared with experimental data obtained for two different initial bubble distributions. 相似文献
94.
Natural abundance 15N NMR spectra have been obtained for bilirubin IX-α using polarization transfer via the INEPT and SINEPT-2 techniques. The resonances for all four nitrogens are clearly resolved. 15N chemical shifts and 15N? 1H coupling constants over one and three bonds are reported. Heteronuclear chemical shift correlation between 15N and 1H for the four NH groups has been established by means of the SINEPT-2 pulse sequence. 相似文献
95.
Thomas Vosegaard Hans J. Jakobsen 《Journal of magnetic resonance (San Diego, Calif. : 1997)》1997,128(2):135-137
Accurate values for the27Al chemical shielding anisotropy (CSA) are reported for sapphire (α-Al2O3). The values (δσ= −17.3 ± 0.6 ppm, ησ= 0.03 ± 0.06) are obtained from single-crystal27Al NMR and appear to be the first convincing determination of an27Al CSA. 相似文献
96.
考虑了Kantorovich-Vertesi有理插值型算子L^*n,s(f,X,x)对L^p[-1,1](1≤p≤∞)空间函数逼近的Jackson型估计。并获得了如下逼近阶:‖L^*n,s(f,X,x)-f(x)‖L^p[-1,1]≤Cp,sw(f,1/n 2)L^p[-1,1] (s>2)。 相似文献
97.
Hans Plesner Jakobsen 《Journal of Functional Analysis》1979,31(3):293-305
Tensor products of holomorphic discrete series representations in reproducing kernel Hilbert spaces are decomposed by considering power series expansions of functions in the direction perpendicular to the diagonal in × . 相似文献
98.
Immobilization of DNA (encoding) on solid nanoparticles requires surface chemistry, which is well established for gold surfaces but often tedious and not generally applicable for many other inorganic surface materials. While substantial effort has been devoted to expanding surface chemistry techniques for solid nanoparticles, considerably less attention has been given to the development of noncovalent attachment of DNA to soft nanoparticles, like liposomes. Here we report a DNA-controlled assembly of liposomes in solution and on solid supported membranes, this process displays remarkably sharp thermal transitions from an assembled to a disassembled state, allowing application of DNA-controlled liposome assembly for the detection of polynucleotides (e.g., DNA) with single mismatch discrimination power. The method is based on a single DNA strand (contains two lipid membrane anchors), which is able to noncovalently attach to a liposome surface. This design enables detection of biological polynucleotide targets as the complementary strand can be unmodified DNA and RNA strands. 相似文献
99.
Blagoi G Keller S Persson F Boisen A Jakobsen MH 《Langmuir : the ACS journal of surfaces and colloids》2008,24(18):9929-9932
Bioactive protein patterns and microarrays achieved by selective localization of biomolecules find various applications in biosensors, bio-microelectromechanical systems (bio-MEMS), and in basic protein studies. In this paper we describe simple photochemical methods to fabricate two-dimensional patterns on a Novolac A derivative polymer (SU-8) and, subsequently, their functionalization with biomolecules. Anthraquinone (AQ) derivatives are used to chemically modify and pattern SU-8 surfaces. Features as small as 20 mum are obtained when using uncollimated light. The X-Y spatial resolution of micropatterned AQ molecules is improved to 1.5 mum when a collimated light source is used. This micropatterning process will be important for the functionalization of MEMS-based biosensors. The method saves several processing steps and can be integrated in cleanroom fabrication thus avoiding contamination of the sensor surfaces. 相似文献
100.
Weil M Puchberger M Füglein E Baran EJ Vannahme J Jakobsen HJ Skibsted J 《Inorganic chemistry》2007,46(3):801-808
Single crystals of disilver(I) monofluorophosphate(V), Ag2PO3F (1), were obtained by slow evaporation of a diluted aqueous Ag2PO3F solution. Compound 1 adopts a new structure type and crystallizes in the monoclinic space group C2/c with eight formula units and lattice parameters of a = 9.2456(8) A, b = 5.5854(5) A, c = 14.7840(13) A, and beta = 90.178(2) degrees. The crystal structure of 1 [R(F2 > 2sigma(F2) = 0.0268, wR(F2 all) = 0.0665] is composed of three crystallographically independent Ag+ cations and PO3F2- anions as single building units. The oxygen environment around each of the Ag+ cations is different, with one Ag+ in distorted octahedral (d(Ag-O) = 2.553 A), one in nearly rectangular (d(Ag-O) = 2.445 A), and one in distorted tetrahedral (d(Ag-O) = 2.399 A) coordination. Additional Ag-F contacts to more remote F atoms located at distances >2.80 A augment the coordination polyhedra for the two latter Ag+ cations. The monofluorophosphate anion deviates slightly from C3v symmetry and exhibits the characteristic differences in bond lengths, with a mean of 1.510 A for the P-O bonds and one considerably longer P-F bond of 1.575(2) A. Compound 1 was further characterized by vibrational spectroscopy (Raman and IR) and solid-state 19F, 31P, and 109Ag MAS NMR spectroscopy. The value for the isotropic one-bond P-F coupling constant in 1 is 1JPF = -1045 Hz. Thermal analysis (TG, DSC) revealed a reversible phase transition at 308 degrees C, which is very close to the decomposition range of 1. Under release of POF3, Ag4P2O7 and Ag3PO4 are the thermal decomposition products at temperatures above 450 degrees C. 相似文献