Chrono

Optical Chronograph. Same as Rotating Drum Ophorite. A Brit perchiorate expl used during Chronograph, described briefly under Chrono-... 

Housmans THM, Koper MTM. 2005a. CO oxidation on stepped Rh[n(lll) x (111)] singlecrystal electrodes A chrono-ampetometric study. J Electroanal Chem 575 39-51. 

These results are plausible since according to Sand a two-fold concentration of a component yields a four-fold transition time. Now, these features show, in contrast to the net separation and pure additivity of polarographic waves and their diffusion-limited currents as concentration functions, that in chrono-potentiometry the transition times of components in mixtures are considerably increased by the preceding transition times of any other more reactive component, which complicates considerably the concentration evaluation of chronopotentiograms. 

Dean, J. S. (1997), Dendrochronology, in Taylor, R. E. and M. J. Aitken (eds.), Chrono-metric Dating in Archaeology, Advances in Archaeological and Museum Science Series, Vol. 2, Plenum, New York. 

A. Schwake, B. Ross, and K. Cammann, Chrono amperometric determination of hydrogen peroxide in swimming pool water using ultramicroelectrode array. Sens. Actuators, B B 46, 242-248 (1998). 

Once the radionuclides reach the sediments they are subject to several processes, prime among them being sedimentation, mixing, radioactive decay and production, and chemical diagenesis. This makes the distribution profiles of radionuclides observed in the sediment column a residuum of these multiple processes, rather than a reflection of their delivery pattern to the ocean floor. Therefore, the application of these nuclides as chrono-metric tracers of sedimentary processes requires a knowledge of the processes affecting their distribution and their relationship with time. Mathematical models describing some of these processes and their effects on the radionuclide profiles have been reviewed recently [8,9,10] and hence are not discussed in detail here. However, for the sake of completeness they are presented briefly below. 

Moreau, J.-F. and Hancock, R. G. V. (1996). Chrono-cultural technique based on the instrumental neutron activation analysis of copper-based artifacts from the contact period of northeastern North America. In Archaeological Chemistry organic, inorganic and biochemical analysis, ed. Orna, M. V., ACS Symposium Series 625, Washington, DC, American Chemical Society, pp. 64-82. 

Chrono- Time C/iwnoamperometry is the following of current (as amp- ) with time... 

The two roots in this mystery word are chrono (meaning time , or as a function of time ) and poten (meaning potential ), so chronopotentiometry is a study of the way in which potential varies with time. 

In the chronoamperometric experiment, we measure current (hence amp- ) as a function of time ( chrono- ). It is usual to commence with the solution around the electrode containing only one redox form of the analyte. 

Misra, S. 2006. Precambrian chrono-straigraphic growth of Singhbhum-Orissa craton, eastern Indian shield An alternative model. Journal Geological Society of India, 67, 356-378. 

Gugerli D (1998) Redestrome. Zur Elektrifizierung der Schweiz 1880-1914. Chronos, Zurich... 

In chickens a pattern similar to a capacity limited-elimination was noticed. The cause may be either a capacity limitation in the SDM metabolism (hydroxylation ) of SDM or extensive drug reabsorption from the cloaca occurring at night(known as chrono-pharma-cokinetics). In the chicken, 58 % of the intravenously administered dose is lost, which is also reported for other birds (24). Thus birds must possess additional metabolic pathways. 

Nicic etal. [450] have applied chrono-coulometry and EQCM to perform UPD of Te monolayers on Au surfaces from HCIO4 solution. 

Lobacz et al. [52] have described partial adsorption ofTl+-cryptand (2,2,2) complex on mercury electrode. From voltocoulom-etry, cyclic voltammetry, and chrono-coulometry, it has been deduced that electroreduction of this complex proceeds via two parallel pathways from the solution and from the adsorbed states, which are energetically close. Also, Damaskin and coworkers [53] have studied adsorption of the complexes of alkali metal cations with cryptand (2,2,2) using differential capacity measurements and a stationary drop electrode. It has been found that these complexes exhibit strong adsorption properties. Novotny etal. [54] have studied interfacial activity and adsorptive accumulation of U02 " "-cupferron and UO2 - chloranilic acid complexes on mercury electrodes at various potentials in 0.1 M acetate buffer of pH 4.6 and 0.1 M NaCl04, respectively. 

Clin Neuropharmacol 18 (suppl 2 S7-S14, 1995 Klemfuss H, Kripke DF Effects of lithium on circadian rhythms, in Chrono-pharmacology. Cellular and Biochemical Interactions. Edited by Lemmer B. New York, Marcel Dekker, 1989, pp 281-297... 

Bizzarre, M., Baker, J. A., Haack, H. and Lundgaard, K. L. (2005) Rapid timescales for accretion and melting of differentiated planetesimals inferred from 26Al-26Mg chrono-metry. Astrophysical Journal, 632, L41-L44. 

Other Techniques - Other electrochemical techniques that could be employed in sensor technology would include potential-step methods (or chrono-amperometry, as current is recorded with time), current-step methods (or chronopotentiometry, as potential is recorded with time) and AC impedance. None of these techniques appear to have yet been applied to catalyst sensing in a systematic way. 

The simplest controlled potential experiment is the potential step [34] illustrated in Fig. 15. Such experiments are sometimes termed chrono-amperometry , signifying that the current (-ampero-) is measured (-metry) as a function of time (chrono-). Sometimes, two steps, as in a double-step experiment [34] [Fig. 16(a)], or a sequence of small steps, as in staircase voltammetry [35—37] [Fig. 16(b)], are applied. When the potential of the working electrode is changed by a step for only a brief period of time before being returned to its original (or near to its original) value, we speak of a pulse . There are many varieties of pulse voltammetry [38—41], some of which are discussed in Chap. 4. 

In spite of its advantages and the simplicity of its performance, chrono-coulometry is seldom used for studying charge transfer kinetics. In fact, the method is much more popular because of its suitability for the study of reactant adsorption at the initial potential, which is manifested as an extra time-independent amount of faradaic charge involved in the potential step. This will be considered in more detail later. 

Potential step perturbation chrono-amperometry, pulse polaro-graphy, and d.c. polarography... 

Formulation of more attractive expressions for the integrals in eqns. (202) or (206) is, of course, useful for the mathematical description of polaro-grams and chrono-amperograms. In addition to this, it is important to derive the corresponding explicit relations between the interfacial concentrations co(0, t), cR(0,f) and potential in order to describe the... 

Within these broad categories two principal classes may be distinguished, depending on whether current or voltage is the controlled parameter. The individuals in each class are often described by an operational nomenclature consisting of an independent-variable part followed by a dependent-variable part (i.e., volt-ammetry, chrono-potentiometry) with some system-specific modifiers (i.e., rotating disk voltammetry). Unfortunately, the whims of history have left the electrochemical nomenclature in a rather confused state. The operational approach has been only partially adopted but seems to be gaining popularity. 

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