Experimental procedure conditions

An automated system for clinical analysis consists of the instmment (hardware), the reagents, and the experimental conditions (time, temperature, etc) required for each deterrnination. The reagents plus the experimental conditions are sometimes referred to as the chemistry of the system. The chemistry employed is generally similar to that used in manual assays because most automated assay methods have been adapted from the manual ones. However, automated analy2ers rarely afford the flexibiUty of experimental procedure that is possible in manual analysis. 

In particular we thought it would be useful to include cross-references of functional group transformations and an experimental procedure, so that the reader will be able to evaluate the reaction conditions at a glance for instance is this reaction carried out at room temperature or at 200 C For 1 h or 5 days Are special catalysts required How is the reaction worked up, what yield can be expected ... 

The synthetic procedure described is based on that reported earlier for the synthesis on a smaller scale of anthracene, benz[a]anthracene, chrysene, dibenz[a,c]anthracene, and phenanthrene in excellent yields from the corresponding quinones. Although reduction of quinones with HI and phosphorus was described in the older literature, relatively drastic conditions were employed and mixtures of polyhydrogenated derivatives were the principal products. The relatively milder experimental procedure employed herein appears generally applicable to the reduction of both ortho- and para-quinones directly to the fully aromatic polycyclic arenes. The method is apparently inapplicable to quinones having an olefinic bond, such as o-naphthoquinone, since an analogous reaction of the latter provides a product of undetermined structure (unpublished result). As shown previously, phenols and hydro-quinones, implicated as intermediates in the reduction of quinones by HI, can also be smoothly deoxygenated to fully aromatic polycyclic arenes under conditions similar to those described herein. 

To develop a terse, broad description of mechanical, physical, and chemical processes in solids, this book is divided into five parts. Part I contains one chapter with introductory material. Part II summarizes aspects of mechanical responses of shock-compressed solids and contains one chapter on materials descriptions and one on experimental procedures. Part III describes certain physical properties of shock-compressed solids with one chapter on such effects under elastic compression and one chapter on effects under elastic-plastic conditions. Part IV describes work on chemical processes in shock-compressed solids and contains three chapters. Finally, Part V summarizes and brings together a description of shock-compressed solids. The information contained in Part II is available in much better detail in other reliable sources. The information in Parts III and IV is perhaps presented best in this book. 

A solution of estradiol (38, 15 mg) in methanol-OD (4 ml) and one drop of 10% deuteriosulfuric acid in deuterium oxide is heated under reflux for 5 days. After cooling the reaction mixture is diluted with ether, washed with dilute sodium bicarbonate solution and water, then dried over anhydrous sodium sulfate. Evaporation of the ether gives crystalline 2,4-d2-estradiol (39, 15 mg, 99%), mp 173-175° (ether-hexane), exhibiting 82% isotopic purity and only one aromatic hydrogen by NMR. (For an experimental procedure describing the exchange of aromatic protons under Clemmensen conditions, see section III-D.)... 

Another important synthetic method for the reduction of ketones and aldehydes to the corresponding methylene compounds is the Woljf-Kishner reduction. This reaction is carried out under basic conditions, and therefore can be applied for the reduction of acid-sensitive substrates it can thus be regarded as a complementary method. The experimental procedure for the Clemmensen reduction is simpler however for starting materials of high molecular weight the Wolff-Kishner reduction is more successful. 

Nevertheless the Elbs reaction is a valuable method for the preparation of dihydroxy benzenes. The experimental procedure is simple, and the reaction conditions are mild a variety of functional groups is tolerated. 

Other examples of esterification with trialkyloxonium salts have been reported.7,8 The present procedure offers the advantages that the reactive carboxylate ion is generated in sitv and that a low-boiling, nonaqueous solvent is employed, whereby the experimental procedure is considerably simplified. A related method has been reported which utilizes a hindered amine wdth dimethyl sulfate [Sulfuric acid, dimethyl csterj as the alkylating agent.9 The present procedure is carried out under somewhat milder conditions and avoids the use of highly toxic reagents. 

Nukiyama was unable to establish a condition on the line CD, and in his original experimental curves he shows this line dotted. However, Farber and Scorah (F2) have reported that with special surface treatment and very careful experimentation, quasistable conditions can be set up on a curve such as CD in pool boiling. Their procedure was to first reach point D by way of ACFD and then to very carefully increase the heat flux. However, any disturbance or sudden change of heat flux when in the region CD caused the system to revert to the stable regions GC or DF. 

This series of reagents is characterized by the use of metals under the appropriate conditions. In this regard, a mixture of zinc dust and titanium tetrachloride in ether provided a useful synthesis of vinyl sulphides43, with the possibility of further substitution alpha to the sulphur atom, as outlined in equation (16). The reaction is easy to carry out and gave yields of 49 to 87%, although the authors do not provide much detail of their experimental procedure and of the purity (chemical or stereochemical) of their products. 

For a while till now, our research group has been involved in studies of the properties of limit flames. Most of the results reported in this chapter were obtained for propane flames, under normal atmospheric conditions, in 300 mm long channels, with a square cross-section. The experimental procedure was described previously [25]. A flame propagating through a stationary mixture in a quenching tube or quenching channel can be characterized by the parameters defined in Figure 6.1.1. 

Experimental conditions are listed in Table 2. After pyrolysis of samples at 1073K, the product char was washed with pure water and chlorine of the leachates was analyzed by ion chromatography. Refer to the reference [3] for a detailed experimental procedure. 

These are essentially tests for sterility (Chapter 23) upon bacterial suspensions performed after treatment with the antibacterial agent for a prescribed time and under controlled conditions. They differ in the manner in which the experimental findings are calculated as well as in the details of experimental procedure. 

Different kinds of experimental procedures have been used and these should be evaluated against the background in which several organisms or several substrates are simultaneously present. There are no essential differences in the design of experiments using pure cultures and those employing metaboli-cally stable consortia. It should be emphasized, however, that even in the latter, the experiments should be carried out under aseptic conditions otherwise, interpretation of the results may be compromised by adventitious organisms. 

The fluid leak-off during hydraulic fracturing can be modeled, calculated, and measured experimentally. Procedures for converting laboratory data to an estimate of the leak-off under field conditions have been given in the literature [1426]. 

The bed void fraction and the Reynolds number were determined with the experimental procedures reported in literature [7]. Inprehminaty experiments, citral hydrogenation was investigated in six parallel reactors under identical reaction conditions, i.e., at 25°C and 6.1 bar hydrogen with the residence time of 156 s. The... 

The closeness of agreement between independent test results obtained by applying the experimental procedure under stipulated conditions. The smaller the random part of the experimental errors which affect the results, the more precise the procedure. A measure of precision (or imprecision) is the standard deviation. 

Rodriguez LC, Garcia RB, Garcia Campana AM, Bosque Sendra JM (1998) A new approach to a complete robustness test of experimental nominal conditions of chemical testing procedures for internal analytical quality assessment. Chemom Intell Lab Syst 41 57... 

Experimental Two different experimental procedures were used in this study, to identify the coal properties of importance in coal conversion which are independent of processing conditions. These were ... 

The liquefaction of coals was studied in a 500 ml magnetically-stirred stainless steel antoclave. Two different reaction conditions were used in this study, hut the experimental procedures were almost the same in both conditions. 

The alloy hydride has been investigated as a useful hydrogenation catalyst for a wide variety of substrates under mild conditions. It is however pyrophoric in air, and an experimental procedure has been developed to avoid this hazard. A related hydride, LaNi4.5Alo.5H5 has similar properties. 

Two conditions must be met if this conclusion is to be revealed by the analysis. First, appropriate experimental procedures must be adopted to assure establishment of elastic equilibrium. Second, the contribution to the stress from restrictions on fluctuations in real networks must be properly taken into account, with due regard for the variation of this contribution with deformation and with degree of cross-linking. Otherwise, the analysis of experimental data may yield results that are quite misleading. 

Wang et al. reported two different reaction conditions for a solvent free Friedlander quinoline synthesis. Initially, they reported the reaction of 2-acetyl anilines 73 with a variety of P-diketoesters 74 using / -Ts()H as the catalyst under microwave conditions to form substituted quinolines 75 <060BC104>. They also reported the same reaction using BiCl3 as the catalyst under thermal conditions <06LOC289>. Both sets of conditions afford high yields and simpler experimental procedures. 

Miriyala and Williamson have described the synthesis of /i-kctocarboxam idcs from primary and secondary amines and 2,2-dimethyl-2H,4H-l,3-dioxin-4-ones as reactive a-oxoketene precursors (Scheme 6.158) [304], The experimental procedure involved heating a mixture of the dioxinone with 2-3 equivalents of the amine at ca. 180 °C for 1-3 min under solvent-free conditions in a sealed vessel by microwave irradiation. A small collection of 18 /3-ketocarboxamides was prepared in very high yields using this protocol. 

A facile method for the oxidation of alcohols to carbonyl compounds has been reported by Varma et al. using montmorillonite K 10 clay-supported iron(III) nitrate (clayfen) under solvent-free conditions [100], This MW-expedited reaction presumably proceeds via the intermediacy of nitrosonium ions. Interestingly, no carboxylic acids are formed in the oxidation of primary alcohols. The simple solvent-free experimental procedure involves mixing of neat substrates with clayfen and a brief exposure of the reaction mixture to irradiation in a MW oven for 15-60 s. This rapid, ma-nipulatively simple, inexpensive and selective procedure avoids the use of excess solvents and toxic oxidants (Scheme 6.30) [100]. Solid state use of clayfen has afforded higher yields and the amounts used are half of that used by Laszlo et al. [17,19]. 

---