Experience carrier definition

Deep state experiments measure carrier capture or emission rates, processes that are not sensitive to the microscopic structure (such as chemical composition, symmetry, or spin) of the defect. Therefore, the various techniques for analysis of deep states can at best only show a correlation with a particular impurity when used in conjunction with doping experiments. A definitive, unambiguous assignment is impossible without the aid of other experiments, such as high-resolution absorption or luminescence spectroscopy, or electron paramagnetic resonance (EPR). Unfortunately, these techniques are usually inapplicable to most deep levels. However, when absorption or luminescence lines are detectable and sharp, the symmetry of a defect can be deduced from Zeeman or stress experiments (see, for example, Ozeki et al. 1979b). In certain cases the energy of a transition is sensitive to the isotopic mass of an impurity, and use of isotopically enriched dopants can yield a positive chemical identification of a level. 

According to classical information theory, founded by Shannon [1948] (see also Shannon and Weaver [1949]), information is eliminated uncertainty about an occurrence or an object, obtained by a message or an experiment. Information is always bound up with signals. They are the carriers of information in the form of definite states or processes of material systems (Eckschlager and Danzer [1994] Danzer [2004]) see Sect. 3.1. 

Activity. The differences found in activity of the catalyst are caused by two effects the definition of the catalyst-to-oil (CTO) ratio and the feed partial pressure in both reactors. The CTO is time averaged over the reaction time and is not clearly defined in the MST. The contact between the catalyst and oil is not constant throughout the experiment. At the beginning of the MST experiment fresh feed encounters fresh catalyst. However, after some time fresh feed meets a partially deactivated catalyst with coke already deposited on it. At the end of the experiment the situation is the opposite of the contact between catalyst and oil in an industrial unit. This makes the definition of the CTO not unambiguous in the case of the MST and can lead to over- or underestimation of the CTO. However, the most important effect is the difference in partial pressure of the feed in both sets of equipment the nitrogen carrier gas lowers the partial pressure in the MR. A lower partial pressure results in a lower conversion. With these two effects a higher activity for the MST can be expected. 

In general, a UV-Vis transmission experiment offers the fastest and most direct method of estimating the optical bulk band gap and should be a priority for any newly synthesized material. A diffuse reflectance or absorption configuration can be used if the sample is not transmissive. If a diffuse reflectance experiment is not available, then photocurrent spectroscopy (as described in Chapter Efficiency definitions in the field of PEC ) with extremely facile redox couples can be performed, though errors in this method may arise from poor charge carrier mobilities or lifetimes and from slow kinetics at the sample-electrolyte interface. 

This evidence is consistent with, but does not provide definitive proof for OAS being the physiologically important precursor of cysteine. Only a limited number of O-esters of serine have been tested for activity with cysteine synthase (Section II,B,2), and no systematic studies have been made to determine whether serine O-esters other than OAS are synthesized by plants, or to identify the physiologically important a-aminopropionyl donor for cysteine synthesis. Experiments analogous to those used to identify the a-aminobutyryl donor for cystathionine and homocysteine synthesis (Section III,A,3) and the physiological carrier in sulfate reduction in Chlorella (Section IV,D,3) should be informative in this respect. 

U-tube experiments are attractive because of their simplicity and their clear-cut interpretation. They give a definite yes/no answer about the capability of synthetic molecules to transport hydrophilic molecules across a hydrophobic barrier. Thus, they unambiguously identify the ability of a molecule or supermolecule to function as an ion carrier. 

A feature of this patent of Ho Tan Tai [43] is the absence of a control experiment where the antifoam is directly sprayed onto cold detergent powder. This means that definite evidence for the effectiveness of the chosen carrier materials in facilitating dispersal of the antifoam, despite a high proportion of solid wax, is not revealed. It also means that there is no evidence either that the chosen carrier materials inhibit storage deaetivation. Finally, we should note that the claimed hydrocarbon-hydrophobed silica antifoams are exemplified by the use of hydrocarbon blends containing either white mineral oil or spindle oil Velocite 6 (manufactured by Mobile). According to the relevant product data sheet [48], the latter material contains a defoamant ... 

The definition of s = R/Sn is useful because s is a quantity which is independent of and consequently of the light intensity. According to Eq. (2.47), s must pass a maximum when the potential is varied across the space charge layer as illustrated qualitatively in Figure 2.14. One branch of the curve is determined by the majority carriers, the other by the minority carriers. The position of the maximum on the (f> scale and the width of the curve depend on the doping of the semiconductor and on the capture cross-sections and Physically speaking, Eq. (2.47) illustrates that for electron-hole recombination at the surface, both holes and electrons must be able to flow into the surface [35]. If cf) is such as to strongly repel either electrons or holes from the surface, s will be low. The validity of Eq. (2.47) has been proved at least qualitatively in many experiments (see, e.g., [5]). 

Despite the numerous theories on the mechanistic pathways for the methanol synthesis, and the extensive investigation, there is still uncertainty about the definition of the role of Cu°, Cu, Cu-Zn alloy, and the carrier sites [222], In the past, it has been assumed that CO hydrogenation is the main pathway for methanol synthesis. However, isotopic labeling experiments conducted by Chinchen et al. [285] have revealed that methanol is formed directly from CO2, whilst CO scavenges the oxygen atoms which hinder the active metal sites [237, 286],... 

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