Example Using Excel

Suppose you have a mixture of hydrocarbons in the inlet stream. You want to find the fraction of the stream that is vapor and the mole fraction of each chemical in the vapor and liquid streams. Table 3.1 shows the flow rates and 2C-values at 180°F and 70psia, using a basis of one mole per unit of time. 

To solve this problem, prepare the spreadsheet as shown in Table 3.2. 

Step 2 The ratios of terml over term2 are calculated and put into column F this column is summed in cell F9, which represents Eq. (3.9). 

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Repeat the 100-cell equilibrium setup of Example 7.2, but starting with all cells in the B form. What speciflc result do you obtain for Wgq at 2000 iterations Then, analyze the values for the interval from 1000 to 2000 iterations statistically using EXCEL or a similar program to obtain average values for the concentrations [A] and [B] and also for Xgq over this period, along with their standard deviations. 

The spreadsheet used for this example is Microsoft Works. A copy of the example using Microsoft Excel can be found on the companion web site http //books.elsevier.com/ companions. 

The page http //www.radford.edu/ wkovarik/lead cites some fascinating sidelights on the history of petrol and its additives, and its links are carefully chosen. For example, the excellent page http //www.chemcases.com/tel summarizes the history of tetraethyl lead and the attendant controversies over its addition to petrol. Though quite small, the site http //www.exxon.com/exxon productdataAube encyclopedia/knock.html contains useful information on the anti-knock properties of petrol and its additives. 

Another type of widely used modeling system is the spreadsheet solver. Microsoft Excel contains a module called the Excel Solver, which allows the user to enter the decision variables, constraints, and objective of an optimization problem into the cells of a spreadsheet and then invoke an LP, MILP, or NLP solver. Other spreadsheets contain similar solvers. For examples using the Excel Solver, see Section 7.8, and Chapters 8 and 9. 

The pH value also affects the ionization of acidic and basic analytes and their electromigration. Since this migration can be opposite to that of the electroos-motic flow, it may both improve and impair the separation. This effect is particularly important in the separation of peptides and proteins that bear a number of ionizable functionalities. Hjerten and Ericson used monolithic columns with two different levels of sulfonic acid functionalities to control the proportion of EOF and electromigration. Under each specific set of conditions, the injection and detection points had to be adjusted to achieve and monitor the separation [117]. Another option consists of total suppression of the ionization. For example, an excellent separation of acidic drugs has been achieved in the ion-suppressed mode at a pH value of 1.5 [150]. 

The analysis of soils and plant material are common examples used to demonstrate ICP applications. Dahlquist and Knoll(43) compared the preparation and ICP analyses of botanicals (16 elements) and soils (11 elements) with few exceptions the ICP values for the CII botanicals were in excellent agreement with the assigned values, and the soil analyses were in excellent agreement with FAA analyses of soil digests. )ones( 4) reported the analysis of 17 elements in plant material and soils but confirmation of the two analyses was not given. Alder, et. aJ.(75) describe the unique analysis of ammonia-nitrogen in soils by gas evolution into an ICP no interferences were observed from the concomitants evaluated and acceptable recoveries were obtained. Irons et. al.(76) compared the ICP analyses of 13 elements in NBS orchard leaves and bovine liver to the data obtained by FAA and energy dispersive x-ray. 

A further example of the use of a chiral anion in conjunction with a chiral amine was recently reported by Melchiorre and co-workers who described the asymmetric alkylation of indoles with a,P-unsaturated ketones (Scheme 65) [212]. The quinine derived amine salt of phenyl glycine (159) (10-20 mol%) provided the best platform with which to perform these reactions. Addition of a series of indole derivatives to a range of a,P-unsaturated ketones provided access to the adducts with excellent efficiency (56-99% yield 70-96% ee). The substrates adopted within these reactions is particularly noteworthy. For example, use of aryl ketones (R = Ph), significantly widens the scope of substrates accessible to iminium ion activation. Expansion of the scope of nucleophiles to thiols [213] and oximes [214] with similar high levels of selectivity suggests further discoveries will be made. 

The ability of polymers to withstand elevated temperatures is critical to many applications. For example, the excellent thermal stability of polysiloxanes is the basis for many of their uses, including their application in low molecular weight... 

This a-aminooxylation has subsequently been successfully extended to the use of ketones as donors [12]. For example, use of cyclohexanone as donor led to (R)-12a in 79% yield and with an excellent enantioselectivity of >99% ee (Scheme 7.12) [12a]. Very recently, the Cordova group reported further examples of this proline-catalyzed a-aminooxylation [13]. In addition, this method has been successfully applied in the synthesis of corresponding chiral 1,2-diols after subsequent derivatiza-tion [13]. Furthermore, computational studies of transition states were carried out [13b],... 

For institutions considering the use of a PBL type of course, there are many examples in the literature for ideas and ready-made examples sufficient for entire courses. A search of university and college websites for connections to PBL can be very fruitful. At this time, some outstanding examples with excellent resources for PBL are the University of... 

The most recent method developed for the nA —> An approach relies on dynamic covalent bond formation using a metathesis reaction. In this case, reactions are typically under thermodynamic control, providing the potential for increased selectivity in product formation. The initial examples using alkyne metathesis toward the formation of SPMs were reported by Adams, Bunz, and coworkers using the precatalyst [Mo(CO)6] [27,28], but rather low yields of the desired products (4) limited general applicability (Scheme 6.2). Recent efforts by Moore and coworkers using a Mo(VI)-alkylidyne catalyst, however, have refined this process such that precipitation-driven reactions now provide moderate to excellent results (see Scheme 6.24) [29]. 

A further example used the supported amino alcohols 45,46 and 47 (Scheme 4.76), where the reagents were pumped up from the bottom of the polymer using a pair of long needles connected to peristaltic pumps. The product was collected from the top using another pump and quenched in a solution of dilute hydrochloric acid. For the first run with catalyst 46, the yields and ee were excellent (94% yield in 97% ee), but when 46 was recovered and reused, the yield dropped to 75% and the ee to 50%. This was ascribed to degradation of both the chiral and backbone sites of the polymer by diethyl zinc, again demonstrating that not only do the solid supports need to be mechanically sound but both the backbone support and active site must be also chemically resistant to the reaction conditions [171]. 

For example, using Microsoft Excel to perform the t-test, one would use the following syntax ... 

Latexes find wide use in industrial and consumer applications, particularly in the areas of synthetic rubber and coatings. Latex paints, for example, provide excellent alternatives to older, oil-based (alkyd) paints, which release substantial quantities of organic solvents to the atmosphere as they dry. Because volatile organic compounds (VOCs) are a factor in depleting the ozone layer, many industrial nations are striving to develop products... 

Radical polymerization techniques that are for example used for the crosslinking of methacrylate-modified polysaccharides [9] are not included in this chapter. Prepolymer crosslinking through radical polymerization techniques as well as non-covalent microgel formation has recently been reviewed in a number of excellent review articles [2, 4, 10-14] and is thus not discussed within this chapter. 

The naturally occurring enantiomer, (+)-anatoxin-a, is much more potent than (—)-anatoxin-a [38]. For example, using conditions that preferentially labeled rat brain a4p2 nACh receptors with [ H]nicotine, the natural enantiomer was found to be 1000-fold more potent than (—[-anatoxin [39]. This enantiospecificity of anatoxin-a has provided an excellent tool for probing the stereospedfidty of the ACh binding site on the nicotinic receptor. 

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