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Microscopic system

The miderstanding of molecular motions is necessarily based on quaiitum mechanics, the theory of microscopic physical behaviour worked out in the first quarter of the 20th century. This is because molecules are microscopic systems in which it is impossible—or at least very dangerous —to ignore the dual wave-particle nature of matter first recognized in quaiitum theory by Einstein (in the case of classical waves) and de Broglie (in the case of classical particles). [Pg.54]

Fig. 5. Block diagram of contact atomic force microscope system in which cantilever deflection monitored optically with position-sensitive photodiode... Fig. 5. Block diagram of contact atomic force microscope system in which cantilever deflection monitored optically with position-sensitive photodiode...
I mentioned temperature at the end of the last chapter. The concept of temperature has a great deal to do with thermodynamics, and at first sight very little to do with microscopic systems such as atoms or molecules. The Zeroth Law of Thermodynamics states that Tf system A is in thermal equilibrium with system B, and system B is in thermal equilibrium with system C, then system A is also in thermal equilibrium with system C . This statement indicates the existence of a property that is common to systems in thermal equilibrium, irrespective of their nature or composition. The property is referred to as the temperature of the system. [Pg.58]

The method of molecular dynamics gives information about the time evolution of a microscopic system, and permits the evaluation of macroscopic properties as time averages. The alternative Monte Carlo method was developed at the end of... [Pg.69]

Classical descriptions of molecular phenomena can be remarkably successful, but we have to keep our eye on the intrinsic quantum nature of microscopic systems. [Pg.72]

Nakhleh Krajcik, 1994) macroscopic system microscopic system symbolic system algebraic system... [Pg.6]

The third problem is like the confusion caused in MT by maintaining the concept of the Ether. Most practitioners of QM think about microscopic systems in terms of the principles of QM probability distributions, superposition principle, uncertainty relations, complementarity principle, correspondence principle, wave function collapse. These principles are an approximate summary of what QM really is, and following them without checking whether the Schrddinger equation actually confirms them does lead to error. [Pg.26]

Figure 3.1 Schematic diagram of the near-field optical microscope system. The structure of the near-field probe tip is illustrated in the circle. (Reproduced with permission from Royal Society of Chemistry [10]). Figure 3.1 Schematic diagram of the near-field optical microscope system. The structure of the near-field probe tip is illustrated in the circle. (Reproduced with permission from Royal Society of Chemistry [10]).
Figure 8.1 (a) Block diagram of the femtosecond near-infrared laser microscope system, (b) Spectrum ofthe light pulse from the Cr F laser, (c) Interferometric autocorrelation trace of SHG signal with envelope curve calculated assuming a chirp-free Gaussian pulse with 35 fs fwhm. [Pg.135]

The experimental set-up for the FCS measurement is illustrated schematically in Figure 8.6. A CW Ar laser (LGK7872M, LASOS lasertechnik GmbH) at 488 nm was coupled to a single mode optical fiber to isolate the laser device from an experimental table on which the confocal microscope system was constructed. This excitation laser light transmitted through the optical fiber was collimated with a pair of lenses, and then was guided into a microscope objective (lOOX, NA 1.35, Olympus). [Pg.139]

The q(T) can be independently measured by a viscometer and the value of y is determined by the PCS measurement at a certain temperature (typically 21 22 °C). Under the condition that the hydrodynamic diameter of the probe molecule is constant in the temperature range examined, we can obtain the temperature of the confocal area. It is worth noting that the present method estimates average temperature inside the confocal volume of the microscopic system because ECS provides the average value of the translational diffusion velocity over multiple fluorescent molecules passing through the sampling area. [Pg.141]

Fig. 2.2.15 Desktop MR microscope system overview (top left) yokeless permanent magnet (top right) and maximum intensity projection image of a blue berry (bottom). Fig. 2.2.15 Desktop MR microscope system overview (top left) yokeless permanent magnet (top right) and maximum intensity projection image of a blue berry (bottom).
The samples were collected from the cathodes 2.5 cm away from the current collector tab, washed in pure dimethyl carbonate (DMC), and soaked in DMC for 30 minutes after removal from Li-ion cells inside an argon-filled glove box. This procedure removed electrolyte salt from the electrode to prevent its reaction with air and moisture. An integrated Raman microscope system Labram made by ISA Groupe Horiba was used to analyze and map the cathode surface structure and composition. The excitation source was an internal He-Ne (632 nm) 10 mW laser. The power of the laser beam was adjusted to 0.1 mW with neutral filters of various optical densities. The size of the laser beam at the sample was 1.2 pm. [Pg.455]

Szabo, G., Pine, P., Weaver, J., Kasari, M. and Aszalos, A. (1992). Epitope mapping by photobleaching fluorescence resonance energy transfer measurements using a laser scanning microscope system. Biophys. J. 61, 661-70. [Pg.70]

Three examples will show how freezing processes can be studied quantitatively and documented using this microscope system. Figure 1.39 shows the change in volume of an isolated islet cell of a mouse as a function of temperature. The different permeability of cell membranes for HzO and CPAs are important for freezing of cell, as Fig. 1.40 shows. [Pg.41]

The system for which we want to write a total continuity equation is all the liquid phase in the tank. We call this a macroscopic system, as opposed to a microscopic system, since it is of definite and finite size. The mass balance is around the whole tank, not just a small, differential element inside the tank. [Pg.18]

Example 2.11. As an example of a force balance for a microscopic system, let us look at the classic problem of the laminar flow of an incompressible, newtonian liquid in a cylindrical pipe. By newtonian we mean that its shear force (resistance that adjacent layers of fluid exhibit to flowing past each other) is proportional to the shear rate or the velocity gradient. [Pg.30]

In most problems involving boundary conditions, the boundary is assigned a specific empirical or deterministic behavior, such as the no-slip case or an empirically determined slip value. The condition is defined based on an averaged value that assumes a mean flow profile. This is convenient and simple for a macroscopic system, where random fluctuations in the interfacial properties are small enough so as to produce little noise in the system. However, random fluctuations in the interfacial conditions of microscopic systems may not be so simple to average out, due to the size of the fluctuations with respect to the size of the signal itself. To address this problem, we consider the use of stochastic boundary conditions that account for random fluctuations and focus on the statistical variability of the system. Also, this may allow for better predictions of interfacial properties and boundary conditions. [Pg.79]

The extent to which multiple fluorescence signals can be distinguished is demonstrated by resolution of five separate fluorochromes within individual, living 3T3 cells (24). None of the fluorochromes employed in this work was conjugated to an antibody, but the potential for extensive multiple labeling with a suitable set of fluorochromes and an appropriately equipped microscope system is clear. [Pg.104]

Legare, F., Ganikhanov, F., and Xie, X. S. 2005. Towards an integrated coherent anti-Stokes Raman scattering (CARS) microscope system. Proc. SPIE 5971 35 0. [Pg.123]

Figure 34 Schematic diagram of microbeam system for biological study. An ion beam from an AVF cyclotron is collimated by collimators and a tantalum disk with microaperture with a diameter of 5-250 pm. The collimated ion beam passes through the room air to a target that is set on the micropositioning stage of an optical microscopic system. Figure 34 Schematic diagram of microbeam system for biological study. An ion beam from an AVF cyclotron is collimated by collimators and a tantalum disk with microaperture with a diameter of 5-250 pm. The collimated ion beam passes through the room air to a target that is set on the micropositioning stage of an optical microscopic system.
The heart of the acoustic microscope system is its acoustic objective. (Atalar and Hoppe 1986)... [Pg.48]

Quate, C. F., Khuri-Yakub, B. T Akamine, S and Hadimioglu, B. B. (1994). Near field acoustic ultrasonic microscope system and method. US Patent 5,319,977. [292]... [Pg.340]

The postulates and theorems of quantum mechanics form the rigorous foundation for the prediction of observable chemical properties from first principles. Expressed somewhat loosely, the fundamental postulates of quantum mechanics assert dial microscopic systems are described by wave functions diat completely characterize all of die physical properties of the system. In particular, there aie quantum mechanical operators corresponding to each physical observable that, when applied to the wave function, allow one to predict the probability of finding the system to exhibit a particular value or range of values (scalar, vector. [Pg.4]

In order to describe microscopic systems, then, a different mechanics was required. One promising candidate was wave mechanics, since standing waves are also a quantized phenomenon. Interestingly, as first proposed by de Broglie, matter can indeed be shown to have wavelike properties. However, it also has particle-Uke properties, and to properly account for this dichotomy a new mechanics, quanmm mechanics, was developed. This chapter provides an overview of the fundamental features of quantum mechanics, and describes in a formal way the fundamental equations that are used in the construction of computational models. In some sense, this chapter is historical. However, in order to appreciate the differences between modem computational models, and the range over which they may be expected to be applicable, it is important to understand the foundation on which all of them are built. Following this exposition. Chapter 5 overviews the approximations inherent... [Pg.105]

Just as there is a fundamental function that characterizes the microscopic system in quantum mechanics, i.e., the wave function, so too in statistical mechanics there is a fundamental function having equivalent status, and this is called the partition function. For the canonical ensemble, it is written as... [Pg.357]


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See also in sourсe #XX -- [ Pg.18 ]




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Confocal microscopic optical systems

Disordered systems microscopic models

Fluid system microscopic structure

Frequency dependence, microscopic systems

Microscope lens system

Microscopic fluctuations disordered systems

Microscopic fluorescence assay detection systems

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