Setup and Principle

Setup and principle of FCS and FCCS have been reviewed extensively previously [12,13]. The technique is based on the statistical analysis of equilibrium fluorescence fluctuations induced by, e.g., the d3mamics of fluorescent molecules in a tiny observation volume. By correlating these fluctuations with itself at a later time r, an autocorrelation curve is obtained, which can be fitted to an appropriate model function to extract the characteristic time scales of the system. The two basic parameters of a FCS autocorrelation curve are the decay time, reflecting time scales of molecules dynamics, and the amplitude, indicating the average number of particles in the detection volume. 

FIGURE 4.23 Setup and principle of surface plasmon resonance (Kretschmann... 

Sketch of the experimental setup and principle of electrochemical micromachining with ultrashort pulses. RE and CE are abbreviations for reference and counter electrode, respectively. 

There exists a wide variety in the setup of ELISA assays (direct binding or competition setups) and the enzymatic reaction utilized [148]. A similar principle to enhance sensitivity by enzymatic coupling is realized after gel electrophoretic separation of proteins. Here proteins are transferred to nitrocellulose ( western blot ) and detected by antibody-coupled enzymes. 

In general, any analytical equipment or procedure used in the field of natural products chemistry and environmental engineering is also helpful in aroma analysis 64,65 The history and principles of such art are described in detail elsewhere and will not be featured here. Gas chromatography (GC), GC-mass spectrometry (MS), and nuclear magnetic resonance (NMR) are the most frequently used techniques along with rather specialized setups such as proton transfer reaction-mass spectrometry66 (PTR-MS) used in retronasal aroma analysis (see Chapters 9.02, 9.06, 9.10-9.11). 

Fig. 47 (a) Basic experimental setup and operating principle of electrochemical... 

The principle of nanoimprint is quite simple. As shown in Fig. lA, NIL uses a hard mold that contains nanoscale features defined on its surface to emboss into polymer material cast on the wafer substrate under controlled temperature and pressure, thereby creating thickness contrast in the polymer material, which can be further transferred through the resist layer via an O2 plasma-based anisotropic etching process. Nanoimprint has the capability of patterning sub-10 nm features, " yet only entails simple equipment setup and easy processing. This is the key reason that NIL attracted wide attention within only a few years after its inception. 

Fig. 1. The flow photolysis setup, (a) Principle of flow photolysis. The caged signaling compound is transported by a gentle flow of buffer from teff to right. The signaling substance is photochemically released in a confined photo-uncaging region and transported by the fluid flow across the cell downstream, (b) Example layout of a microfluidic channel device, top wew.The stededstructures are 25 pm high.

Fig. 7. Photoelectron jpectroscapy of size-selected cluster anions. Schemes of (a) the experimental setup and (b) the principle.

There was also described and discussed the relatively new Fourier transform infrared emission spectroscopy (IRES), its principle, an appropriate FT-IRES setup and applications. FT-IRES is unique in that it does not require an external radiation source, because the sample itself is the source. The radiation emitted from the sample is collected and sent to the detector. The ratio of the sample signal to that from a black body source represents the spectrum. However, appli-... 

Optical Detection on Centrifugal Microfluidic Lab-on-a-Disc Platforms, Fig. 3 The experimental setup and operating principles of the centrifugal microfluidic test stand platform 1], These principles have been... 

In view of the described difficulties, it makes sense to automate the measuring setup and procedure. An imaging measuring system that facilitates rapid, spatially resolved determination of the magnitude and orientation of stress birefringence with high accuracy has been devdoped. The applied functional principle essentially corresponds to the setup indicated in Figure 2, but the analyzer is operated by a motor and the human observer is replaced by a matrix camera. 

During the last 25 years, a gas flow perturbation technique has been used for physicochemical measurements in homogeneous and heterogeneous systems. This technique is reversed-flow gas chromatography (RF-GC). In this entry, the basic theoretical principles, the experimental setup, and the applications of this technique are reviewed. 

Electrochemical Promotion for the Abatement of Gaseous Pollutants, Fig. 1 (a) Basic experimeiital setup and operating principle of electrochemical prrano-tion with 0 -conducting supports, (b) Catalytic rate, r, and turnover frequency, TOP, response of C2H4 oxidation on Pt deposited on YSZ, an 0 conductor, upon step changes in applied current. T = 370 °C, po2 = 4.6 kPa, PC2I14 = 0.36 kPa. Also shown dashed line) is the catalyst-electrode potential, Uwr, response with respect... 

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