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181.
A simple desalting procedure for the coupling of a polymer microchip injector to mass spectrometry is proposed. The overall process is based on the adsorption of proteins on a poly(vinylidene difluoride) (PVDF) membrane, which are then directly eluted in the spraying solution. This microchip-based approach has been successfully applied to small drugs, peptides and proteins originally diluted in phosphate-buffered saline (PBS). Moreover, when eluting the retained proteins in small volumes, a preconcentration is obtained. The combination of single-use, mass-produceable, low-sample-consumption, easy-to-automate, miniaturized polymer injectors with easy-to-handle solution-exchange membranes makes this system particularly amenable to screening applications. 相似文献
182.
We propose a modification of special relativity in which a physical energy, which may be the Planck energy, joins the speed of light as an invariant, in spite of a complete relativity of inertial frames and agreement with Einstein's theory at low energies. This is accomplished by a nonlinear modification of the action of the Lorentz group on momentum space, generated by adding a dilatation to each boost in such a way that the Planck energy remains invariant. The associated algebra has unmodified structure constants. We also discuss the resulting modifications of field theory and suggest a modification of the equivalence principle which determines how the new theory is embedded in general relativity. 相似文献
183.
Gelson Manzoni de Oliveira Manfredo H?rner Milton Seiffert Adailton Jo?o Bortoluzzi 《Journal of chemical crystallography》1999,29(2):131-136
Abstract List
Index abstracts 相似文献184.
Plischke M Vernon DC Joós B Zhou Z 《Physical review. E, Statistical physics, plasmas, fluids, and related interdisciplinary topics》1999,60(3):3129-3135
In recent work, we presented evidence that site-diluted triangular central-force networks, at finite temperatures, have a nonzero shear modulus for all concentrations of particles above the geometric percolation concentration p(c). This is in contrast to the zero-temperature case where the (energetic) shear modulus vanishes at a concentration of particles p(r)>p(c). In the present paper we report on analogous simulations of bond-diluted triangular lattices, site-diluted square lattices, and site-diluted simple-cubic lattices. We again find that these systems are rigid for all p>p(c) and that near p(c) the shear modulus mu approximately (p-p(c))(f), where the exponent f approximately 1.3 for two-dimensional lattices and f approximately 2 for the simple-cubic case. These results support the conjecture of de Gennes that the diluted central-force network is in the same universality class as the random resistor network. We present approximate renormalization group calculations that also lead to this conclusion. 相似文献
185.
186.
Summary We study completeness of weighted spaces of vector-valued functions. Also, the dual of a weighted space of vector-valued continuous
functions on a locally compact space is characterized as a space of vector valued Radon measures with values in the topological
dual of the range space.
Research supported by a grant from the National Science Foundation, GP 22713.
Entrata in Redazione il 25 ottobre 1970. 相似文献
187.
Ljubo Golič Jože Slivnik Marjan Levstek Anka Rihar 《Monatshefte für Chemie / Chemical Monthly》1968,99(1):289-290
Ohne Zusammenfassung 相似文献
188.
189.
M. Nishijima S. Masuda M. Jo M. Onchi 《Journal of Electron Spectroscopy and Related Phenomena》1983,29(1):273-278
High-resolution electron energy loss spectra of hydrogen-covered Ni(110) surfaces both at 100 and 300 K are presented. The adsorbed sites of hydrogen atoms are discussed.High-resolution electron energy loss spectra of hydrogen covered Ni(110) surfaces have been studied. Tentative models for the adsorbed sites of hydrogen atoms are as follows: (1) For the (2 × 1)-H surface, hydrogen is adsorbed in the three-coordinated sites of the rudimentary (111) face of the unreconstructed Ni(110) substrate. (2) For the low-temperature (1 × 2)-H surface, hydrogen is adsorbed in the three-coordinated sites and, probably, in the two-fold hollow sites of the distorted Ni(110) substrate. (3) For the room-temperature (1 × 2)-H surface, hydrogen is disorderedly adsorbed in the three-coordinated, two-fold hollow and short-bridge sites and, possibly, in the octahedral sites of the distorted Ni(110) substrate. Some of the unresolved problems in the above assignments are summarized: (1) Strictly, the three-coordinated sites above are somewhat different from those discussed in the molecular-beam diffraction study [5]. (2) For the low-temperature (1 × 2)-H surface, the loss associated with hydrogen in the two-fold hollow sites is apparently not observed. (3) Intensity changes of the three losses for the room-temperature (1 × 2)-H surface with increasing hydrogen pressure (Fig. 2) are not well understood. 相似文献
190.
This article reviews the most relevant chemical and structural aspects that influence the spin-crossover phenomenon (SCO). Special attention is focussed on the recent development of SCO coordination polymers. The different approaches currently being explored in order to achieve multifunctionality in SCO materials are discussed. 相似文献