DETERMINATION OF THE ENERGY GAP OF C60 MOLECULE USING THIRD-ORDER DERIVATIVE ABSORPTION SPECTROSCOPY

Comparison of classic and derivative UV spectrophotometric methods for determination of dextromethorphani hydrobromidumA method for the fast determination of dextromethorphani hydrobromidum in pharmaceutical preparations by classic spectrophotometry - zero and first-, second- and third-order derivative spectrophotometry, using "peak - peak" (P - P) and "peak - zero" (P - O) measurements has been performed. The calibration curves are linear within the concentration range of 1.0 - 25.0 μg ml-1 for dextromethorphani hydrobromidum. The procedure is simple, rapid and the results are reliable.

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Determination of chlorpromazine and its sulphoxide in pharmaceutical dosage forms by third-order derivative ultraviolet spectroscopy

The Analyst ◽

10.1039/an9851001117 ◽

1985 ◽

Vol 110 (9) ◽

pp. 1117 ◽

Cited By ~ 61

Author(s):

Adedigbo A. Fasanmade ◽

Anthony F. Fell

Keyword(s):

Dosage Forms ◽

Order Derivative ◽

Ultraviolet Spectroscopy ◽

Third Order ◽

Pharmaceutical Dosage Forms

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A New Criterion to Determine the Start of Combustion in Diesel Engines

Journal of Engineering for Gas Turbines and Power ◽

10.1115/1.2179471 ◽

2005 ◽

Vol 128 (4) ◽

pp. 928-933 ◽

Cited By ~ 47

Author(s):

Tomaž Katrašnik ◽

Ferdinand Trenc ◽

Samuel Rodman Oprešnik

Keyword(s):

Experimental Data ◽

Order Derivative ◽

Cylinder Pressure ◽

Third Order ◽

First Law Of Thermodynamics ◽

The Third ◽

Crank Angle ◽

New Criterion ◽

Start Of Combustion

A new criterion for the determination of the start of combustion (SOC) from the diesel engine in-cylinder pressure diagram was developed. It is defined as the maximum of the third-order derivative of the cylinder pressure with respect to the crank angle. This criterion declares SOC more precisely than other previously published criteria based on pressure diagnostics. This fact was proven analytically and was discernable from the analysis of the experimental data. Besides its accuracy it is also robust enough to allow automatic evaluation of the SOC during processing of the pressure data for a large number of cycles. By applying the first law of thermodynamics analysis to the engine cylinder it was discovered that the third-order derivative of the in-cylinder pressure with respect to the crank angle is the most suitable criterion for determination of the SOC from the in-cylinder pressure diagram. Subsequently, the criterion was validated through experimental data analysis of the in-cylinder pressure diagrams for various engine speeds and loads. In order to evaluate the rate of heat release (ROHR), which formed the base for the experimental validation, in-cylinder pressure diagrams were processed with a computer code based on the first law of thermodynamics. The cylinder pressure was measured with an advanced piezoelectric sensor at the resolution 0.1 deg CA. Top dead center was determined with the capacitive top dead center sensor. Due to the analytic foundation of the developed method and its validation through highly accurate experimental data it can be concluded that new criterion is credible for the determination of the SOC.

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