The Experimental Setup

As the NMR experiment can be performed with a single or several nuclei of different species simultaneously, the probes should be simultaneously tunable at several different frequencies. Usually, the experiments are performed in single-, double-, or tripleresonance, but typically only one species of nucleus is observed at the corresponding Lar- 

Normally, the audio filter/amplifier gains are slightly different, the receiver electronics introduces offsets to each channel, and the quadrature detection is not perfect, making the NMR signal in the practice looks like  

These artifacts can be eliminated by a phase cycling scheme called CYCLOPS [46], To make the discussion of this phase cycling easier, let s consider that S is usually sufficiently 

Transm. Received signal number phase phase quad. 

True signal, including offsets (a and b), and amplitude mismatching (A B) 

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Figure 19-1 shows the experimental setup with the position of the steel test pieces and the anodes. The anodes were oxide-coated titanium wires and polymer cable anodes (see Sections 7.2.3 and 7.2.4). The mixed-metal experimental details are given in Table 19-1. The experiments were carried out galvanostatically with reference electrodes equipped to measure the potential once a day. Thus, contamination of the concrete by the electrolytes of the reference electrodes was excluded. The potentials of the protected steel test pieces are shown in Table 19-1. The potentials of the anodes were between U(2u-cuso4 = -1-15 and -1.35 V. 

For example in paint shops, TCE evaporates and causes air pollution. The contaminated air has 250 ppm TCE in it and this can be fed to a moving bed reactor at 300°C that is charged with OXITOX (Chovan et al, 1997) The kinetics must be studied experimentally. The experimental setup is shown in Figure 4.5.1 and the following description explains the recommended procedure. In the experimental unit shown, the feed is contained under pressure in a gas cylinder. Two percent of the feed is saturated by TCE and diluted with the rest of the feed. The rate is calculated as ... 

The experimental setup uses the ROTOBERTY internal recycle reactor. The catalyst basket of this is charged with W = 35.5 g or V = 44.3 cm of OXITOX that contains 0.25 mol, i.e., 26.5 g of sodium carbonate. 

Figure 1 Schematic diagram showing the basic elements of a MOKE experiment. The angle of incidence, the wavelength of the light, and the orientation of the magnetization, M, relative to the plana of incidence are variables in the experimental setup.

The instrumentation required to measure the hysteresis loop of a ferromagnetic surface with MOKE can be very simple. Figure 4a shows one such implementation of the experimental setup for analysis of ultrathin film samples maintained in a... 

Figure 1 shows a schematic representation of the experimental setup used to study the metal-fullerene... 

Clearly, however, there are many ways of changing the experimental setup depending on the aim of the procedure. There are many opportunities... 

An important method for producing semiconductor layers is the so-called molecular beam epitaxy (MBE) (see [3,12-14] and [15-19]). Here, atoms of the same or of a different material are deposited from the vapor source onto a faceted crystal surface. The system is always far from thermal equilibrium because the deposition rate is very high. Note that in this case, in principle, every little detail of the experimental setup may influence the results. 

The experimental setup for high-speed CZE can be seen in Figure 9.8. Highspeed CZE, or fast CZE (FCZE), yielded 70 000 to 90 000 theoretical plates for the separation of amino acid mixtures. Complete separation was achieved in under 11s, using a capillary length of 4 cm (24). 

The experimental setup for a titration is shown in Figure 4.7. The flask contains vinegar, a water solution of a weak organic add called acetic acid. A solution of sodium hydroxide of known concentration is added from a buret. The net ionic equation for the acid-base reaction that occurs is... 

Figure 13-8. Typical results for interna, plroiocniission measurements on an ITO/ OPPV/Ca diode at various applied voltages. Tire lines are least-square tils and their extrapolation yields the barrier height for that applied voltage. Inset shows the experimental setup. Reproduced with permission from IIIV1-...

Depending on the sample geometry, the resulting currents may be in the pico- and subpico-ampere range. It is essential either to change the sample geometry or to make sure that the experimental setup resolves these small currents. 

Figure 4.15 Schematic of the experimental setup used in an adiabatic demagnetization experiment.

The experimental setup in this reaction is exactly as that described in Note 2. 

The experimental setup is depicted schematically in Figure 1.2. Upon varying the potential of the catalyst/working electrode the cell current, I, is also varied. The latter is related to the electrocatalytic (net-charge transfer) reaction rate re via re=I/nF, as well known from Faraday s law. The electrocatalytic reactions taking place at the catalyst/solid electrolyte/gas three-phase-boundaries (tpb), are ... 

Figure 5.34. Schematic of the experimental setup for using X-ray photoelectron spectroscopy (XPS) to investigate the catalyst-electrode surface.6 Reprinted with permission from the American Chemical Society.

Figure 5.48. Schematic of the experimental setup for using Scanning Tunelling Microscopy (STM) to investigate a Pt(lll) catalyst-electrode surface.78 Reprinted with permission from Elsevier Science.

Can one use STM to study spillover/backspillover phenomena and to confirm the origin of electrochemical promotion The answer is positive and the experimental setup used for the first demonstration of electrochemically controlled spillover/backspillover between a catalyst-electrode (Pt) and a solid electrolyte (p"-Al203) is shown in Figure 5.48.78,79 A polished Pt(lll) single crystal (lOmmxlOmmxlmm) was mounted on an appropriately carved polycrystalline p"-Al203 sample (20mmx20mmx3mm). 

The experimental setup is shown in Figure 9.23. The Pt-black catalyst film also served as the working electrode in a Nafion 117 solid polymer electrolyte cell. The Pt-covered side of the Nafion 117 membrane was exposed to the flowing H2-02 mixture and the other side was in contact with a 0.1 M KOH aqueous solution with an immersed Pt counterelectrode. The Pt catalyst-working electrode potential, Urhe (=Uwr)> was measured with respect to a reversible reference H2 electrode (RHE) via a Luggin capillary in contact with the Pt-free side of the Nafion membrane. 

Figure 11.3. Schematic of the experimental setup used (a) to induce electrochemical promotion (via YSZ) on Ir02 and Ir02-Ti02 porous catalyst films (b) to compare the electrochemical promotion induced on Pt via YSZ and via Ti02 and (c) to compare the electrochemical promotion behaviour induced by varying UWR on a Rh porous catalyst film (left) and on a fully dispersed Rh catalyst supported on porous (80 m2/g) YSZ support.22...

The experimental setup used for the first bipolar or wireless NEMCA study is shown in Figure 12.6.8 An YSZ disc with two terminal Au electrodes and one Pt catalyst film deposited on one side and a reference Au electrode on the other side is placed in a single-chamber reactor. Ethylene oxidation on the Pt catalyst film was chosen as a model reaction.8... 

The different studies are mainly reported on the OBLIN site (NASA). The main goal is to simplify and integrate all the functions to be achieved in the beam combiner by using integrated optics and optical fibre components. Consequently, the compactness, the stability and the reliability are significantly improved. Figure 15 illustrates the simplification of the experimental setup. 

Modified ARC Experiments. Pressure and temperature data at pre-exotherm temperatures may be collected by running the ARC under modified conditions. A schematic diagram of the experimental setup of a modified ARC apparatus is shown in Figure 1. 

The experimental setup sketched in Figure 5.2.3 comprises a burner with ad = 22 mm nozzle exit diameter and a driver unit (loudspeaker) fixed at its base. The burner body is a cylindrical tube of 65 mm inner diameter containing a set of grids and a honeycomb followed by a convergent nozzle with an area contraction ratio of cr= 9 1. 

The treated tips were connected to the experimental setup (Fig. 33), which is able to bring them into close proximity with the atomically flat electrode (plates of freshly cleaved,... 

The schematic diagram of the experimental setup is shown in Fig. 2 and the experimental conditions are shown in Table 2. Each gas was controlled its flow rate by a mass flow controller and supplied to the module at a pressure sli tly higher than the atmospheric pressure. Absorbent solution was suppUed to the module by a circulation pump. A small amount of absorbent solution, which did not permeate the membrane, overflowed and then it was introduced to the upper part of the permeate side. Permeation and returning liquid fell down to the reservoir and it was recycled to the feed side. The dry gas through condenser was discharged from the vacuum pump, and its flow rate was measured by a digital soap-film flow meter. The gas composition was determined by a gas chromatograph (Yanaco, GC-2800, column Porapak Q for CO2 and (N2+O2) analysis, and molecular sieve 5A for N2 and O2 analysis). The performance of the module was calculated by the same procedure reported in our previous paper [1]. 

Experimental setup and procedures. The experimental setup for N2O decomposition consisted of a gas mixing section, a reactor and a gas analysis section. A quartz fixed bed reactor of 5 mm I.D. was used, containing 20 mg of catalyst (106-212 mm) diluted with... 

The advantages of SHG are that it uses visible light and that the experimental setup is relatively simple. Limitations of SHG are the lack of a good theory on the microscopic level and its inabihty to identify adsorbed species. 

In the following, after a brief description of the experimental setup and procedures (Section 13.2), we will first focus on the adsorption and on the coverage and composition of the adlayer resulting from adsorption of the respective Cj molecules at a potential in the Hup range as determined by adsorbate stripping experiments (Section 13.3.1). Section 13.3.2 deals with bulk oxidation of the respective reactants and the contribution of the different reaction products to the total reaction current under continuous electrolyte flow, first in potentiodynamic experiments and then in potentiostatic reaction transients, after stepping the potential from 0.16 to 0.6 V, which was chosen as a typical reaction potential. The results are discussed in terms of a mechanism in which, for methanol and formaldehyde oxidation, the commonly used dual-pathway mechanism is extended by the possibility that reaction intermediates can desorb as incomplete oxidation products and also re-adsorb for further oxidation (for the formic acid oxidation mechanism, see [Samjeske and Osawa, 2005 Chen et al., 2006a, b Miki et al., 2004]). 

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