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11.
RIVLIN T. J.; RUSCHEWEYH ST.; SHAFFER D.; WIRTHS K. J. 《IMA Journal of Numerical Analysis》1983,3(3):327-332
Given (1, 0), n N, we discuss the optimal recoveryof (), for analytic and bounded in < 1, from the knowledge of the values of at n points z1,.zm[0,l),where these points are chosen to produce the least possibleintrinsic error. The optimal algorithms are explicitly determined. 相似文献
12.
A FORTRAN computer program for automatic neutron activation analysis is presented. The program locates and identifies peaks
in a gamma-ray spectrum, calculates peak areas and the concentrations of the elements of interest in the sample. This program
was specifically designed for the SLOWPOKE reactor, it uses a semi-absolute method and does not need standards or flux monitors.
The program was written so as to minimize the computation time, and a typical 4096-channel spectrum is processed in five seconds
by an IBM 360/75 computer. 相似文献
13.
Two routes to 1,1-dithiolate complexes cis-[Ru(CO)2(S2X)2] [X = NMe2, OEt, PPh2, P(OEt)2] are presented. From the reaction of NH4S2P(OEt)2 with the ruthenium(II) complex generated upon reduction of RuCl3.3H2O by CO in 2-methoxyethanol, along with the expected mononuclear product, cis-[Ru(CO)2{η2-S2P(OEt)2}2], binuclear [Ru(CO){η2-S2P(OEt)2} {μ,η1,η2-S2P(OEt)2}]2 was also produced. The latter has been crystallographically characterized and shows a trans-arrangement of carbonyls and cis-arrangement of terminal and bridging dithiolate ligands. 相似文献
14.
Dickert FL Forth P Lieberzeit PA Voigt G 《Fresenius' Journal of Analytical Chemistry》2000,366(8):802-806
Molecularly imprinted polyurethanes were used as sensor materials for monitoring the degradation of automotive engine oils. Imprinting with characteristic oils permits the analysis of these complex mixtures without accurately knowing their composition. Mass-sensitive quartz crystal microbalances (QCMs) coated with such layers exhibit mass effects in addition to frequency shifts caused by viscosity, which can be compensated by an uncoated quartz or a non-imprint layer. Incorporation of degradation products into the imprinted coatings is a bulk phenomenon, which is proven by variation of the sensor layer height. Therefore, the resulting sensor effects are determined by the degradation products in the oil. 相似文献
15.
M. Dülk ST. Fischer M. Bitter M. Caraccia W. Vogt E. Gini H. Melchior W. Hunziker A. Buxens H.N. Poulsen A.T. Clausen 《Optical and Quantum Electronics》2001,33(7-10):899-906
A monolithically integrated and fully packaged Mach–Zehnder interferometer with semiconductor optical amplifiers (MZI-SOA) is demonstrated as polarisation-independent high-speed demultiplexer for up to 160 Gbit/s optical time division multiplexed (OTDM) data streams. 相似文献
16.
A theoretical study of the 21Ag ← 11Ag two-photon transition and its vibronic band in trans-stilbene
JONNA STÅLRING LAURA GAGLIARDI PER-ÅKE MALMQVIST ROLAND LINDH 《Molecular physics》2013,111(11):1791-1796
The two-photon spectrum of the 21Ag ← 11Ag transition in trans-stilbene has been calculated at the complete active space self-consistent field (CASSCF) level of theory. Energies were obtained at the complete active space second-order perturbation (CASPT2) level of theory, while the geometries of both the initial and final states were optimized at the CASSCF level. The energy and the geometry optimizations were performed using an active space of 14 electrons in 14 active π orbitals. The vibrational frequencies of both states and the two-photon transition (TPT) cross-section were calculated with a smaller active space where the two lowest π orbitals were kept inactive. A newly implemented algorithm, in the quantum chemical package Molcas was used to determine the two-photon transition intensity. This method requires only the linear response of the CASSCF wavefunction. Furthermore, the vibronic structure of this TPT was studied. The Franck-Condon factors were obtained by calculating the overlap between the vibrational states involved, which were determined from the force fields of both the initial and final states, at the CASSCF level of theory. The results are in agreement with experiment. 相似文献
17.
JONNA STÅLRING MARTIN SCHÜTZ ROLAND LINDH GUNNAR KARLSTRÖM PER-OLOF WIDMARK 《Molecular physics》2013,111(21):3389-3399
The low-energy region of the intermolecular potential energy hypersurface (PES) of the ammonia dimer was studied at the level of second-order Moller-Plesset perturbation theory (MP2) using a very large basis set. Individual minima were located on the PES employing the counterpoise (CP) correction to account for the basis set superposition error (BSSE). Apart from these canonical MP2 calculations local MP2 (LMP2) calculations were performed. For the latter the BSSE at the correlated level is inherently absent by virtue of the local truncation of the virtual space. Results from canonical and local MP2 calculations are compared and the reliability of the LMP2 method for intermolecular complexes and clusters is discussed. The canonical MP2 calculations predicted five minimum structures, the four most stable ones lying energetically very close. For these four structures single point MP2 energy calculations with a further extended basis set (1024 functions for the ammonia dimer) were performed. The equilibrium dissociation energies so obtained are close to the one-particle basis set limit, as illustrated by a remaining BSSE of less than 0.2 kJ mol?1. The geometry optimizations at the LMP2 level, using the three most stable canonical MP2 structures as initial geometries, all collapsed to a single minimum corresponding to an asymmetric structural arrangement. A canonical MP2 single point calculation, at that geometry, revealed that the LMP2 minimum structure is virtually as stable as the lowest minima on the canonical MP2 PES. Based on these calculations the global minimum of the ammonia dimer was assigned to a part of the PES represented by an asymmetric structure with an equilibrium dissociation energy of 13.5±0.3 kJ mol?1 相似文献
18.
Miglė Graužinytė Joe Forth Katherine A. Rumble Dr. Paul S. Clegg 《Angewandte Chemie (International ed. in English)》2015,54(5):1456-1460
Millimeter‐scale tubes are observed to sprout from water droplets injected into a bath of toluene containing ethanol and silica colloids. This phenomenon requires that first a membrane is formed by the colloids which self‐assemble at the droplet interface, and second, that the ethanol preferentially partitions into the aqueous phase leading to an internal over‐pressure. Tube growth, eruption, and shuffling droplets are subsequently observed, depending on the concentration of ethanol and colloids selected. This work opens many possibilities in the field of biomimetic droplets for fundamental studies of artificial growth at the microscale and for emulsion‐related applications. 相似文献
19.
F. L. Dickert Peter Forth Peter Lieberzeit Matthias Tortschanoff 《Analytical and bioanalytical chemistry》1998,360(7-8):759-762
The technique of molecular imprinting – a novel tool of sensor material synthesis – can be successfully combined with mass-sensitive transducers. Imprinted polymers are prepared in presence of inert analytes acting as molecular templates. The remaining imprint allows the molecular recognition of an analyte due to host-guest-interactions. The sensor properties of devices coated with imprint polymers can be tuned to the analyte by variation of the polymerization solvent and the amount of cross-linker added. A further sensitivity enhancement can be achieved by rising the resonant frequencies of QMBs and SAW resonators, since the signal to noise-ratio increases in an approximately linear manner with the oscillation frequency. 相似文献
20.
Honghao Hou Jin Li Xiangming Li Joe Forth Jie Yin Xuesong Jiang Brett A. Helms Thomas P. Russell 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(30):10248-10253
Amine‐functionalized polyhedral oligomeric silsesquioxane (POSS), the smallest, monodisperse cage‐shaped silica cubic nanoparticle, is exceptionally interfacially active and can form assemblies that jam the toluene/water interface, locking in non‐equilibrium shapes of one liquid phase in another. The packing density of the amine‐functionalized POSS assembly at the water/toluene interface can be tuned by varying the concentration, the pH value, and the degree of POSS functionalization. Functionalized POSS gives a higher interface coverage, and hence a lower interfacial tension, than nanoparticle surfactants formed by interactions between functionalized nanoparticles and polymeric ligands. Hydrogen‐bonded POSS surfactants are more stable at the interface, offering some unique advantages for generating Pickering emulsions over typical micron‐sized colloidal particles and ligand‐stabilized nanoparticle surfactants. 相似文献