Doctor test method

An indication of naphtha composition may also be obtained from the determination of aniline point (ASTM D-1012, IP 2), freezing point (ASTM D-852, ASTM D-1015, ASTM D-1493) (Fig. 4.2), cloud point (ASTM D-2500) (Fig. 4.3), and solidification point (ASTM D-1493). And, although refinery treatment should ensure no alkalinity and acidity (ASTM D-847, ASTM D-1093, ASTM D-1613, ASTM D-2896, IP 1) and no olefins present, the relevant tests using bromine number (ASTM D-875, ASTM D-1159, IP 130), bromine index (ASTM D-2710), and flame ionization absorption (ASTM D-1319, IP 156) are necessary to ensure low levels (at the maximum) of hydrogen sulfide (ASTM D-853) as well as the sulfur compounds in general (ASTM D-130, ASTM D-849, ASTM D-1266, ASTM D-2324, ASTM D-3120, ASTM D-4045, ASTM D-6212, IP 107, IP 154) and especially corrosive sulfur compounds such as are determined by the Doctor test method (ASTM D-4952, IP 30). 

Corrosive sulfnr componnds can be detected by their effect on copper and the form in which the general copper strip corrosion test (ASTM D1838) for petrolenm prodncts is applied to liqnefied petrolenm gas. Hydrogen sulfide can be detected by its action on moist lead acetate paper, and a procedure is also used as a measure of sulfur compounds. The method follows the principle of the standard Doctor test. 

Doctor Test A method which can be used to determine the sweet or sour nature of gasoline by treating gasoline with a solution of lead plumbite and sulfur. As an example, the reaction which occurs with methylmercaptan is as follows ... 

The mercaptan-sulfur determination may be waived at the option of the Inspector, if the fuel is considered Doctor sweet when tested in accordance with Method 5203 of Federal Test Method Standard No 791... 

Gonzaga CC. Subcritical crack growth in dental ceramics effect of the material (microstructure) and the test method. Doctoral thesis. University of Sao Paulo 2007. 

ASTM D 4952-97. Standard test method for qualitative analysis for active sulfur species in fuels and solvents (Doctor Test). 

Doctor test n. Method for detecting the presence of mercaptan sulfur in gasolines, naphthas, and kerosenes. 

Today s rapid-test methods range from the traditional DC load to AC conductance to advanced electrochemical impedance spectroscopy (EIS). Each has its advantages and limitations—and none fully satisfies all requirements. No single device can assess all battery characteristics on the fly. Much like a doctor examining a patient, or a weatherman forecasting the weather, several methods are needed to assess the overall condition. 

However, a sample taken in the doctor s office can be properly packed and shipped to a special laboratory, if necessary. Because endosulfan leaves the body fairly quickly, these methods are useful only for finding exposures that have occurred within the last few days. At this time, these methods can only be used to prove that a person has been exposed to endosulfan. The test results cannot be used to predict if you wiU have any adverse health effects. Exposure to other chemicals at the same time at hazardous waste sites could cause some confusion in understanding these results. More information about tests to find endosulfan in the body is presented in Chapters 2 and 6. 

There are some tests that can show if you have been recently exposed to trichloroethylene since this chemical can be measured in your breath. Also, a doctor can have trichloroethylene or a number of breakdown products of trichloroethylene measured in your urine or blood. None of these tests, however, is routinely available at your doctor s office. If the measurements are done soon after the exposure, the breath levels can indicate whether you have been exposed to a large amount of trichloroethylene or only a small amount. Urine and blood tests can also show if you have been exposed to large amounts of this chemical. Because one of the breakdown products leaves your body very slowly, it can be measured in the urine for up to about 1 week after trichloroethylene exposure. However, exposure to other similar chemicals can produce the same breakdown products in your urine and blood. Therefore, these methods cannot determine for sure whether you have been exposed to trichloroethylene. For more information on medical tests, see Chapters 2 and 6. 

Several very sensitive and specific tests can detect carbon tetrachloride in exposed persons. The most convenient way is simply to measure carbon tetrachloride in exhaled air, but carbon tetrachloride can also be measured in blood, fat, or other tissues. Because special equipment is needed, these tests are not routinely performed in doctors offices but your doctor can refer you to where you can obtain such a test. Although these tests can show that a person has been exposed to carbon tetrachloride, the test results cannot be used to reliably predict whether any bad health effects might result. Because carbon tetrachloride leaves the body fairly quickly, these methods are best suited to detecting exposures that have occurred within the last several days. Further information on how carbon tetrachloride can be measured in exposed humans is given in Chapter 6. 

Bioanalyzer can be considered another version of commercial biosensors for off-line analysis. It was developed to have capabilities of complete analysis, short response time, specificity, and sensitivity that allows a quick clinical test. Abbott Vision, Boehringer-Mannheim Reflectron, and Kodak Ektachem DT60 (IBI Biolyzer is the new name) are used for cholesterol measurement in doctors offices. Bioanalyzer consists of biological and transducing component that are not physically connected. The uniqueness of this separation provides the versatility of analysis, i.e., use of disposable and different biological component for multi-components measurements. In authors laboratory, Kodak Ektachem DT60 was used successfully to determine cholesterol in some food matrices as well as in off-line process control. The analysis time was only 10 minutes compared to 1-2 days for the GC and HPLC methods. Complicated... 

Aside from the fact that chemical substances make them sick, some MCS patients also develop allergies and food intolerances. It s best to let yourself be treated by a therapist or doctor who can test for such things. Here, too, avoidance is the best medicine, as opposed to using all sorts of medications intended to suppress the allergic reactions (although in cases of anaphylactic shock, medicine is a matter of life and death ). Allergy and food intolerance treatment now includes a number of methods, such as low-dose antigen therapy (LDA), enzyme-potentiated desensitization (EPD neutralization injections) and the provocation/neutralization method (injections). 

Arsenic is readily detected the Marsh test was devised in 1836 and was used for over a hundred years. More sophisticated and very sensitive methods are now available, using X-ray analysis or a technique known as mass spectrometry which detects the arsenic atoms. Even before the Marsh test a careful scientific process of experiment would sometimes be successful, as demonstrated by the doctor in the case of Mary Blandy in 1752 (see case notes p. 223). Arsenic remains in tissues of the body for a long time, hence analysis of Napoleon s hair was possible long after his death (see case notes p. 222). The sensitive analysis of hair and nails from the body of American president Zachary Taylor, exhumed in 1991, also established that he was not poisoned in 1850. 

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