Sequence of Experiment

Sequence of experiment can be divided into two main types. In the first type, one of the boundary values of the independent variable is set, and then consecutive transfer from one experimental point to another takes place until the second boundary value will be achieved. A plan of such experiment is called a consecutive plan. 

In the second type, the value of the independent variable alternates randomly. Such a plan of experiment is usually called a randomized plan. 

The consecutive plan is widely used in many sensor experiments, especially in tests where the sequence of experiment itself is a peculiar parameter. Examples can be the sensor tests, where the sensor function is accompanied by hysteresis. 

The randomized plan is also suited to many sensor experiments. Its main arguments are based on the fact that the external (conbolling) conditions of experiment can vary in time and some undetected faults can influence the value of the independent measuring variable. The main concept of randomization is based on the fact that the systematic influential factors, which are hard to control with certain accuracy, should become the accidental factors for their statistical control. However, the randomization may be unnecessary in the complex experiments, when the establishment of the fixed experimental conditions requires substantial extra time and the accidental sequence of transfer from one test condition to others brings even more time expenditures. 

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For a sequential test, the number of experiments is not predefined. Rather, experiments are performed sequentially (surprise ), and the series terminated as soon as enough data is available that a decision can be made as to whether the difference is large enough . True, it is theoretically possible for such a sequence of experiments to be indefinitely long in practice, however, it is far more common for the situation to become decidable after fewer experiments than are required for the case of a fixed number of experiments. 

In a typical protocol, the sequence of experiments would be as follows (1) MRM for the parent compound (2) a search for hits using the MRMs included in the biotransformation table and (3) performance of EPI scans on the two most abundant ions found in the MRM scans from the biotransformation tables. An exclusion list is incorporated for those transitions that one wants to eliminate from enhanced product scan data acquisition. 

Of the multitude of ID 13C NMR experiments that can be performed, the two most common experiments are a simple broadband proton-decoupled 13C reference spectrum, and a distortionless enhancement polarization transfer (DEPT) sequence of experiments [29]. The latter, through addition and subtraction of data subsets, allows the presentation of the data as a series of edited experiments containing only methine, methylene and methyl resonances as separate subspectra. Quaternary carbons are excluded in the DEPT experiment and can only be observed in the 13C reference spectrum or by using another editing sequence such as APT [30]. The individual DEPT subspectra for CH, CH2 and CH3 resonances of santonin (4) are presented in Fig. 10.9. 

Another useful bimetallic for fuel cell electrodes is Pt/Ru. Ruthenium is readily oxidized to Ru02 by calcination after it is impregnated. The PZC of ruthenium oxide is unknown. Propose a comprehensive sequence of experiments with which the SEA method can be applied for the synthesis of a Pt/Ru bimetallic catalyst supported on carbon. The goal is to have intimate contact between the Pt and Ru phases in the final, reduced catalyst. 

Vander Heyden, Y, Bourgeois, A., and Massart, D. L. (1997). Influence of the sequence of experiments in a ruggedness test when drift occurs. Anal. Chim. Acta 347, 369—384. 

The catalyst was dissolved in SCCO2, hydrogen was added and this phase remained inside the reactor over the entire sequence of experiments. An aqueous solution of itaconic acid (16) was brought via an HPLC piunp... 

After the above study of methylation for this type of glass, the length-change sample was methylated in situ (162). As the methyl groups formed by this treatment were stable, a sequence of experiments could be conducted without the need to remethylate the sample at an intermediate... 

Of course, a successful proposal must also forge ahead into less familiar territory. It is not enough to conduct the easy experiments you must approach the cutting edge or forefront of your field. For this reason, Aga goes on to describe how the optimized immunoassay will eventually be used to test for analytes in more complex environmental samples, and Spain proposes a sequence of experiments that will culminate in the deposition of translationally hot metal atoms on a self-assembled monolayer system. The important point in these examples is how authors develop a clear and logical order for their proposed work. 

This paper describes the historical sequence of experiments performed during the development of a new FCC process designed for low aromatic mid-distillate production. 

In investigating such a sequence of experiments the following fundamental questions arise. When Cs is adsorbed on W, will it evaporate as an ion or as an atom Is it adsorbed as an atom or as an ion Can both adatoms and adions exist on the surface Will the answers depend on the concentration of adsorbed Cs When oxygen is adsorbed on W, will it exist as adions, adatoms, or admoles Which species of particle will evaporate most readily When H2O is adsorbed on W, will it decompose Will H, H2, 0, O2, and H2O exist on the surface Which species will evaporate most readily and at what temperatures What will be the influence of one species on the behavior of the others Lest such questions be considered idealistic and incapable of being answered, let the reader be assured that some of them already have been answered by experiments and analyses to be described later. 

Viewing psychosis as an indeterminate but potentially problem-solving process (rather than a disease process) is consistent with major trends in contemporary psychiatry (Bleuler, 1965 Searles, 1961). As indicated earlier, the effects of LSD on normal subjects has given impetus to the emerging concept of schizophrenia as an orderly, natural sequence of experience that should be permitted to run it course rather than suppressed, arrested, or obliterated. Representative of this trend, Kaplan (1964) describes the outcome of this process ... 

Finally, the right level of perseverance is mainly a decisionmaking problem optimizing the sequence of experiments according to a project s specific risk, wild cards , and a conscious decision in favor of long-term research areas are means to come up with a well-balanced portfolio. 

In a similar sequence of experiments as in the case of the ammonium analogue, tetramethylphosphonium iodide reacted with phenyl- or methyllithium first to give trimethylphosphoniummethylide (Wittig also used the name trimethylphosphine-methylene to account for the doubly-bound resonance form 9a), which again was trapped with benzophenone to yield 10 and its hydroiodic acid adduct 11 respectively 22). 

These plots show a sequence of experiments leading to the point where the batch failed to crystallize and the series ended, only to begin again at some other point or by another investigator. 

Many catalytic testing situations benefit from statistical methods of planning efficient sequences of experiments. 

Researchers are used to planning experiments. Their project plans are often presented as a sequence of experiments, each of those addressing another critical aspect of the subject. Since the results of the first experiment are not exactly predictable, all subsequent experiments which build upon these results bear many uncertainties. Any attempt to take the possible variations in results into account will result in a massive complexity of the plan to cover the ramifications from each experiment. At this stage many efforts to establish a reliable plan are given up, simply because the plan becomes too complex to be of any use. As a solution other plans are designed which assume only the desired result at the end of each experiment. Inevitably such plans have to be modified frequently, since they are over-optimistic. 

Is the sequence of experiments logical Are the parts adequately linked ... 

There should be a correlation between the demonstrations and the sequence of experiments performed by the students in their practical classes. For active participation of students, the teacher may call individual student, in turn, to help him in demonstration work. 

Experimental design is the process of planning a minimum sequence of experiments for altering parameters simultaneously, thus providing a mathematical framework from which the maximum amount of information can be... 

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