Laboratory equipment, standard

Solvent-shift method is simple and fast in the selection of polymers that can be used in ASD development, and does not require any special laboratory equipment (standard laboratory equipment can be used). This method can be readily automated in a 96-well format or can run in any size of laboratory scale. The co-solvent quench method is broadly applicable to most poorly water-soluble drug candidates while pH-shift method is limited to ionic compounds. 

Fig. 6.2. The solidification of salol can be followed very easily on a temperature-gradient microscope stage. This can be made up from standard laboratory equipment and is mounted on an ordinary transmission light microscope.

A number of different methods to monitor the amount of methylimidazole left in a final ionic liquid are known. NMR spectroscopy is used by most academic groups, but may have a detection limit of about 1 mol%. The photometric analysis described by Holbrey, Seddon, and Wareing has the advantage of being a relatively quick method that can be performed with standard laboratory equipment [13]. This makes it particularly suitable for monitoring of the methylimidazole content during commercial ionic liquid synthesis. The method is based on the formation and colorimetric analysis of the intensely colored complex of l-methylimidazole with cop-per(II) chloride. 

Length, area, and volume measure the size of an object. Length refers to one dimension, area refers to two dimensions, and volume refers to three dimensions of space. Size measurements require standard measuring devices, such as rulers or measuring cups. Figure 1-14 shows some standard laboratory equipment for measuring volume. 

EXDET Test. A dispersant effectiveness test, named EXDET, was developed to address concerns associated with available laboratory dispersant effectiveness test procedures [160]. The EXDET procedure uses standard laboratory equipment (such as a Burrell Wrist-Action shaker) and small volumes of water, oil, and chemical dispersant. Other features include the capabilities to mass balance the dispersed and nondispersed oil and to generate replicate data for statistical analysis. 

The simplest form of emission spectroscopy is called flame spectroscopy. Flame spectroscopy can be used to identify some common elements. No fancy equipment is needed. The best way to do flame spectroscopy is to use a platinum loop. This piece of standard laboratory gear consists of a fine, 2-inch (5.1-cm) platinum wire twisted into a loop and embedded in a 4-inch (10.2-cm) glass rod. The only other lab equipment needed is a Bunsen burner or its equivalent. 

The total-chlorine method has been used extensively in the determination of spray residues of the chlorinated hydrocarbons 56). Usually the kind of insecticide applied has been known, and by means of the proper factor the chlorine values could be calculated to the insecticide originally used. This calculation is not entirely valid, as the determinations do not differentiate between the insecticide and its degradation products or other contaminants containing organic chlorine. The values obtained by the total-chlorine method are useful, however, because they indicate the magnitude of the residue and the analysis can be made in a short time with standard laboratory equipment. 

For reactions at atmospheric pressure, standard laboratory glassware such as round-bottomed flasks or simple beakers from 0.25 to 2 L can be used. A protective mount in the ceiling of the cavity enables the connection of reflux condensers or distillation equipment. An additional mount in the sidewall allows for sample withdrawal, flushing with gas to create inert atmospheres, or live monitoring of the reaction with a video camera. Most of the published results in controlled MAOS have been obtained from reactions in sealed vessels, and thus in the following mostly accessories for sealed-vessel reaction conditions are described. 

The equipment is quite adequate for screening purposes. In its simplest form (i.e., a glass tube in an oven), it is a relatively low cost technique that can be assembled with standard laboratory equipment. However, the simple test set-up provides no quantitative thermal data for scale-up purposes, but only T0 values. The more advanced instruments like the SEDEX and SIKAREX, which are also isoperibolic calorimetry equipment, acquire specific thermal stability data that can be used for scale-up. Furthermore, the small autoclave tests provide gas evolution data. 

The preparation described here of 3-cyclopentene-1-carboxylic acid from dimethyl malonate and cis-1,4-dichloro-2-butene is an optimized version of a method reported earlier3 for obtaining this often used and versatile building block.6 The procedure is simple and efficient and requires only standard laboratory equipment. 3-Cyclopentene-1-carboxylic acid has previously been prepared through reaction of diethyl malonate with cis-1,4-dichloro(or dibromo)-2-butene in the presence of ethanolic sodium ethoxide, followed by hydrolysis of the isolated diethyl 3-cyclopentene-1,1-dicarboxylate intermediate, fractional recrystallization of the resultant diacid to remove the unwanted vinylcyclopropyl isomer, and finally decarboxylation.2>7 Alternatively, this compound can be obtained from the vinylcyclopropyl isomer (prepared from diethyl malonate and trans-1,4-dichloro-2-butene)8 or from cyclopentadiene9 or cyclopentene.10 In comparison with the present procedure, however, all these methods suffer from poor selectivity, low yields, length, or need of special equipment or reagents, if not a combination of these drawbacks. 

Na (aq) -I- Cl (aq) - - H20(f) Assume that you have a coffee-cup calorimeter, solid NaOH, 1.00 mol/L HCl(aq), 1.00 mol/L NaOH(aq), and standard laboratory equipment. Write a step-by-step procedure for the investigation. Then outline a plan for analyzing your data. Be sure to include appropriate safety precautions. If time permits, obtain your teacher s approval and carry out the investigation. 

Assume that you have solid PbCh, a strip of zinc metal, filter paper, an electronic balance, and any other standard laboratory equipment. 

Equipment needed for the above procedures is not always available in the standard laboratory. A useful and widely used method for preparing solutions of dinitrogen pentoxide in nitric acid involves the distillation of mixtures of oleum and potassium nitrate in absolute nitric acid. Another method uses a solution of sulfur trioxide and ammonium nitrate in nitric acid. Although the original report states that solutions of 28 2 % dinitrogen pentoxide in nitric acid can be prepared via this method, a later report suggests that concentrations higher than 30 % are not attainable. 

Polished pellets were prepared from all the zones of both the seams for reflectance measurements. These reflectance measurements were carried out on equipment standard in coal petrographic laboratories in North America. Two pellets were examined for each zone, and three traverses for each pellet and 20 readings for each traverse were recorded. The determinations were conducted maintaining the same standard conditions throughout the investiga-... 

Another advantage of immunohistochemistry is that tissues of a small size (e.g., biopsies) can be used. This is important because it is better to detect tumors at an early stage, when they are small. The necessity of early detection cannot be overemphasized. Very small tumors and fine-needle aspirates cannot be used for biochemical assays. Although the DCC assay provides quantitative results, it does not take into account the relative amount of the connective tissue in the specimen, the presence of carcinoma in situ lesions, or normal ducts and lobules. These limitations are not encountered when using paraffin sections. In addition, immunohistochemistry allows the use of archival tissues when fresh tissues are not available. This method does not require any special, expensive equipment and can be carried out in any standard laboratory. 

Generally scientists involved in method development are not the same individuals who will ultimately use the method on a day-to-day basis. As listed in steps 5, 6, and 8 of Table 5, it is quite necessary to consider the analysts who will ultimately be called upon to use the method as well as the equipment and instrumentation in the laboratory. Methods that are destined for the QC laboratory should, when possible, utilize standard laboratory equipment, be independent of the technician performing it, and be easily transferable. The following is an actual example of a method that was developed without consideration of the aforementioned concerns. 

This chapter should describe the complete set of instrumental and other analytical parameters as well as special laboratory equipment and analytical accessories such as size and type of sample vials, pipettes and syringes etc., standard laboratory glassware and equipment excepted. 

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