Experimental plan

Designing an experiment is like designing a product. Every product serves a purpose so should every experiment. This purpose must be clearly defined at the outset. It may, for example, be to optimize a process, to estimate the probabiUty that a component operates properly under a given stress for a specified number of years, to evaluate the relative effects on product performance of different sources of manufacturing and end use variabiUty, or to determine whether a new process is superior to an existing one. An understanding of this purpose is important in developing an appropriate experimental plan. 

Practical considerations enter into the experimental plan in various other ways. In many programs, variables are introduced at different operational levels. For example, in evaluating the effect of alloy composition, oven temperature, and varnish coat on tensile strength, it may be convenient to make a number of master alloys with each composition, spHt the alloys into separate parts to be subjected to different heat treatments, and then cut the treated samples into subsamples to which different coatings are appHed. Tensile strength measurements are then obtained on all coated subsamples. 

The effect of different pai ameters such as temperature, pressure, modifier volume, dynamic and static extraction time on the SFE of the plant were investigated. The orthogonal array experimental design method was chosen to determine experimental plan, (5 ). In this design the effect of five parameters and each at five levels were investigated on the extraction efficiency and selectivity [4]. 

The experimental plan will also specify approximate values for The reaction rate for a key component is calculated using Equation (7.10), and the results are regressed against measured values of bgut, , and... 

As far as the bench-chemist is concerned, the following nonexhaustive list of points should be incorporated into the experimental plan ... 

This effect has not been found in the source measurements carried out by the same or different operators in the same or different laboratories, with the same make of apparatus. None of the levels of error of measurement ever relates to an experimental value of flashpoint. This is incredible since over the past few years techniques of statistical control of testing and experimental planning have been developed which are now compulsory for some activities under the ISO 9000 quality standard. 

One of the most widely used experimental plans is that of the factorial design, or some variation of it (two of the techniques in the following section utilize it). By multiple regression techniques, the relationships... 

This approach can be used with other simple rate expressions in order to determine a representative value of the reaction rate constant. Moreover, the experimental plan on which this technique is based will provide data over such a range of fraction conversions that it is readily... 

Sodium chlorite reacts very violently with organic compounds of divalent sulfur, or with free sulfur (which may ignite), even in presence of water. Contact of the chlorite with rubber vulcanised with sulfur or a divalent sulfur compound should therefore be avoided [1]. Application of factorial design techniques to experimental planning gave specific conditions for the safe oxidation of organic sulfides to sulfoxides using sodium chlorite or calcium hypochlorite [2],... 

Scharff, M. F., Goldman, S. R., Flanagan, T. M., Gregory, T. K., and Smott, L. D., Proj ect to Provide an Experimental Plan for the Merc 6 x 6 Fluidized Bed Cold Test Model, Department of Energy, Final Report J772042-FR Contract EY-77-C-21-8156 (1978)... 

If the null hypothesis was wrong, then the data would vary around a line offset from the line representing /x0, and get closer and closer to it, instead. Eventually, at some value of n, this line would cross the converging lines representing the critical limits around /x0, indicating the result. This is the basic picture, shown in Figure 20-2. For a sequential experimental plan, the sequence is terminated at the first significant experiment, as shown. 

Combinatorial chemistry and HT E are powerful tools in the hands of a scient ist, as they are a source for meaningful consistent records of data that would be hard to obtain via conventional methods within a decent timeframe. This blessing of fast data acquisition can turn into a curse if the experimentalist does not take precautions to carefully plan the experiments ahead and the means of handling the data and analyzing them afterwards. The two essential elements that ensure a successful execution of ambitious projects on a rational and efficient basis are, therefore, tools that enable the scientist to carefully plan experiments and get the most out of the minimum number of experiments in combination with the possibility of fast and reliable data retrieval from databases. Therefore, experimental planning and data management are complementary skillsets for the pre- and post experimental stages. 

Figure 11.4 Three illustrative examples why the density and choice of points are essential for the experimental planning stage. It can be seen in all three cases that the wrong choice of experimental points can result in missing the opportunity of finding the local optimum.

As vitally important as the capabilities for experimental planning, screening, and data analysis are the procedures for preparation of inorganic catalysts. In contrast to the procedures usually applied in conventional catalyst synthesis, the synthetic techniques have to be adapted to the number of catalysts required in the screening process. Catalyst production can become a bottleneck and it is therefore necessary to ensure that HTE- and CombiChem-capable synthesis technologies are applied to ensure a seamless workflow. 

One important way in which thermodynamics is utilized in hydrometallurgical process development is as a guide to experimental planning and process selection and evaluation. A high degree of accuracy is not needed at this stage of process development. Estimates which are within 15 to 20% of the true value are frequently adequate for making feasibility calculations. 

To ensure that the experimental plan is in compliance with standards for microarray information collection... 

Three case studies are presented next that demonstrate approaches to troubleshooting problems. The first two cases were developed with poor hypotheses, while the last case study had a problem that was solved quickly using strong hypotheses and a strong experimental plan for verification. 

Once the type of design is specified, sufficient information is available to generate a table containing a fist of calibration samples, along with the values of each design variable for each sample. However, it is important to note that there are additional considerations which can further alter this experimental plan ... 

Proposed Studies Proposed Work Experimental Plan... 

The planning of good experiments for an in situ spectroscopic homogeneous catalytic study is a non-trivial matter. Indeed, the number and quality of the pure component spectra recovered are strongly dependent on the experimental planning. 

No single spectrometer is the perfect input to Eq. (2). Each experimental plan has limitations and many of these are associated with accessible compositions, temperatures and pressures. In addition, there is the issue of having an overdetermined system as remarked previously. Taken together, we arrive at the conclusion ... 

---