Work, standard Step 7

The second is a standard Grignard reaction and you just need to remember that the aqueous work-up step is not usually written down but is still needed. 

The yield of dibromobenzene can be determined directly firom the reaction mixture by gas chromatography after addition of an internal standard. With this technique, the work-up step can be omitted in the screening experiments. 

The method has no salt factor. Prepare the calibration curve by using the working standard solution described under 2b in Section 12.5.2.2 and by following the procedure outlined for analysis of the sample. However, since the working standard solutions do not contain any magnesium salt, the centrifugation step after the heating process is not necessary. The amount of NaOH solution necessary to establish the reaction pH of about 10.5 should be determined in a pre-treatment e qieriment. 

Further analytical work by SSMS on the sample is considered if certain rare earth impurities require lower error limits. Internal referencing is employed in which the reference is an appropriately selected rare earth. The rare earth levels, determined with internal referencing, are then compared to the determinations for these same elements in the original sample. The ratios of these determinations should be constant and this constant can be used as a correction factor for all of the determinations in the original sample. The Laboratory is presently changing the internal standardization step to incorporate the use of isotope dilution when it is practical. 

Once the conditions in the laboratory have been investigated and working standards developed, methods of dealing with a spill can be devised. Every laboratory using biohazardous organisms should have an action protocol, which is a step-by-step procedure to be followed if a spill should occur. Action protocols should be brief, direct, and straightforward, and should be prominently displayed. The objective of an action protocol is to protect the individuals in the laboratory from infection and to prevent the spread of the agent. 

This complexation removes the AICI3 from the reaction mixture and necessitates the use of at least one full equivalent of the Lewis acid to allow the reaction to go to completion. Acidic aqueous work-up is necessary to liberate the ketone from its aluminum chloride complex, as illustrated by the following examples. Because the work-up step is standard for most organic reactions, we will omit it from future schemes. 

Approved techniques for manual and mechanical sampling are often documented for various commodities handled in commerce by industiy groups. Examples are the International Standards Organization (ISO), British Standards Association (BSA), Japan Institute of Standards (JIS), American Society for Testing Materi s (ASTM), and the Fertihzer Institute. Sampling standards developed for use in specified industry applications frequently include instructions for labora-toiy work in sample preparation and analysis—steps (2) and (3) above. 

Tolling presents a special consideration that can make the training step easier. Typically a toller s technical staff, operators and mechanics are knowledgeable in the basic operations and tasks related to the toller s specialty. For example, experienced operators may know operations of the reactors, columns, exchangers, and packaging equipment quite well. The mechanical personnel may be very familiar with the required safe work practices, equipment cleaning procedures and maintenance tasks for standard vessels and piping. 

The hazardous waste standard requires employers to make certain that when showers are a necessary step in the decontamination process, their employees shower at the end of their work shift and when leaving the hazardous waste site. Sanitation-related showers (unlike decontamination showers) are understood to be voluntary. Decontamination and emergency showers should be located close to the worksite. Sanitary showers may be located at some distance from the worksite. A statement in the safety plan encouraging good personal hygiene and daily showers is a good idea. In addition, workers should be encouraged to shower daily even if no shower is available at the worksite. 

Fig. 5.4 shows a carpet plot of overall efficiency against specific work for the cooled [CBTJici plant (single step) with pre.ssure ratio and combustion temperature as parameters. As shown earlier, by the preliminary air standard analysis and the subsequent calculations in Chapter 4, there are relatively minor changes of thermal efficiency compared with the uncooled plant [CBT]iuc, but there is a major effect in the reduction of specific work. 

Standard operating procedures (SOPs) are step-by-step job instructions which can help workers perform their jobs safely and efficiently. When the end users are involved in their design, SOPs can provide a basis for arriving at a method of work agreed-to by different shifts. In this sense, SOPs can be used to develop training programs and specify measures of competence. Because of the importance of SOPs in the work situation, a systematic framework is needed to enable the design of reliable procedures which are acceptable by the workforce. 

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