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251.
Bosma AY Ulijn RV McConnell G Girkin J Halling PJ Flitsch SL 《Chemical communications (Cambridge, England)》2003,(22):2790-2791
Two-photon fluorescence microscopy was introduced as a tool to assess enzyme accessibility and to quantify enzyme reactions rates on solid supports. 相似文献
252.
253.
Possible definitions of the long range dependence (LRD) of a stationary point process are discussed. Examples from the standard queueing literature are considered and shown to be amenable to yielding processes with long range count dependence. In particular the effect of the single-server queueing operator, whereby one point process is transformed into another via the mechanism of a simple queue, is examined for possible long range dependence of both the counting and interval properties of the output process. For an infinite server queue, the output is long range count dependent if and only if the input is long range count dependent. 相似文献
254.
Gerhard Rein 《Mathematical Methods in the Applied Sciences》1990,13(2):159-167
Classical solutions of the relativistic Vlasov–Maxwell system are considered, describing a collisionless plasma with two species of particles. ions and electrons. It is shown that as the ion mass m tends to infinity, the corresponding solution of the relativistic Vlasov–Maxwell system tends to the solution of a system, in which the ions are given by a fixed ion background and only the electrons move. The convergence is uniform on compact time intervals, with an asymptotic convergence rate of m?1. 相似文献
255.
Alexander W. Willemse Jan C. M. Marijnissen Arjan L. van Wuyckhuyse Rein Roos Henk G. Merkus Brian Scarlett 《Particle & Particle Systems Characterization》1997,14(4):157-162
Photon correlation spectroscopy (PCS) is a technique to measure rapidly particle size in the sub-micrometre region. The use of PCS is, however, limited by concentration. The upper limit is due to multiple scattering of the incident light and the lower limit is determined by the fact that fluctuations of the number of particles in the measuring zone have a significant influence on the apparent diffusion coefficient. In this paper a signal processing method is described which differentiates this influence. With this system the lower limit is no longer limited to about 100 particles in the measuring volume corresponding to a concentration of 109 particles/cm3. The limitation is now the intensity of the scattered light, which becomes too weak at a concentration of about 50 particles/cm3. As a consequence of this work, a revision to the basic theory of PCS may be necessary. Moreover, the new processing method also permits the measurement of the particle concentration in the sample. 相似文献
256.
D. Rein 《Annalen der Physik》1988,500(4):303-310
The possibility to detect nonconventional scalar, pseudoscalar or tensor interactions (SPT) in the angular distribution of pions produced coherently in neutrino nucleus reactions is reexamined. It is found that the angular distribution does not differ qualitatively from a corresponding distribution arising from conventional VA interactions unless the energy of the outgoing pion is restricted. Even then SPT interactions are likely to be overshadowed by transverse VA interactions which can mimic the former at finite although small momentum transfer Q2. 相似文献
257.
Valeriani C Allen RJ Morelli MJ Frenkel D Rein ten Wolde P 《The Journal of chemical physics》2007,127(11):114109
We present a method for computing stationary distributions for activated processes in equilibrium and nonequilibrium systems using forward flux sampling. In this method, the stationary distributions are obtained directly from the rate constant calculations for the forward and backward reactions; there is no need to perform separate calculations for the stationary distribution and the rate constant. We apply the method to the nonequilibrium rare event problem proposed by Maier and Stein, to nucleation in a 2-dimensional Ising system, and to the flipping of a genetic switch. 相似文献
258.
Previously established necessary and sufficient conditions for finite stationary moments in stable FIFO GI/GI/s queues exist only for the first component of the workload vector, the delay, and the final component, which behaves as the
total work in the system. In this paper, we derive moment results for all the components of the stationary workload vector in stable FIFO GI/GI/s queues. As in the case of stationary delay, the moment conditions for workload components incorporate the interaction between
service-time distribution, traffic intensity and the number of servers in the queue. 相似文献
259.
Tiit Kaljuvee Merli Keelmann Andres Trikkel Rein Kuusik 《Journal of Thermal Analysis and Calorimetry》2011,105(2):395-403
The thermooxidative decomposition of four oil shale samples from Estonia, Jordan, Israel and Morocco and one sample of Estonian
oil shale derivative, semicoke, was studied with the aim to determine the characteristics of the process and the differences
of it related to the origin of oil shale. The experiments with a Setaram Setsys 1750 thermoanalyzer coupled to a Nicolet 380
FTIR Spectrometer were carried out under non-isothermal conditions up to 1000 °C at the heating rates of 1, 2, 5, 10 and 20 °C min−1 in an oxidizing atmosphere. A model-free kinetic analysis approach based on the differential isoconversional method of Friedman
was used to calculate the kinetic parameters. The results of TG–DTA–FTIR analyses and the variation of activation energy E along the reaction progress α indicated the complex character of thermooxidative decomposition of oil shale and semicoke,
being at that the most complicated for Estonian and Jordanian oil shale characterized by higher content of organic matter
as compared to the other samples studied. 相似文献
260.
Rein Vihalemm 《Foundations of Chemistry》2011,13(2):97-107
The autonomy of chemistry and the legitimacy of the philosophy of chemistry are usually discussed in the context of the issue
of reduction of chemistry to physics, and defended making use of the failure of reductionistic claims. Until quite recent
times a rather widespread viewpoint was, however, that the failure of reductionistic claims concerns actually epistemological
aspect of reduction only, but the ontological reduction of chemistry to physics cannot be denied. The new problems of the
autonomy of chemistry in the context of reductionism seem to be ontological and metaphysical. In the present paper it is argued
that there is no need for some kind of metaphysical-ontological underpinning for rejection of the secondary positions of chemistry
and philosophy of chemistry with respect to physics and philosophy of physics. The issue can be elucidated in terms of the
philosophy of science accepting practical realism (also known by other names). 相似文献