Instrument line symbols

Figure 12-61D. Centrifugal compressor surge control schematic diagram shows instrumentation required when primary flow-measuring device is located in centrifugal compressor discharge line. Symbols T = temperature P = pressure A = differential across compressor outlet to inlet. See Reference 89 for a detailed discussion. (Used by permission White, M. H. Chemical Engineering, p. 54, Dec. 25,1972. McGraw-Hill, Inc. All rights reserved.)...

FIGURE 18.52 Instrumentation diagram of a temperature control system for a stirred tank reactor symbols electrical instrument line, TT temperature transmitter, TRC temperature recorder-controller. 

Instrumentation normally is denoted by a circle in which the variable being measured or controlled is denoted by an appropriate letter symbol inside the circle. When the control device is to be located remotely, the circle is divided in half with a horizontal line. Table 1.3 gives various instrumentation symbols and corresponding letter codes. The specific operating details and selection criteria for various process instrumentation are not discussed in this book. The reader is referred to earlier works by Cheremisinoff [1,2] for discussions on essential control and measurement instrumentation. 

Sometimes it is convenient to prefix these symbols by L to indicate that the designation is for a line and not a vessel or instrument. 

The second term describes the bound-to-bound contributions, that is the rotovibrational bands of the van der Waals dimer. If the system does not form dimers, this term and the following two terms all vanish. For practical use, the d function in this term should be replaced by an instrumental slit function, or perhaps with some Lorentzian if pressure broadening affects the individual lines (as will often be the case). In any case, the d function is symbolic for the relatively sharp dimer lines that... 

Figure 18.5 Most atomic anions are not detectable on common ICS-AES instruments. Addition of detectable anions can be used as proxies for more abundant anions. For a DNA duplex it was shown that cacodylate serves as a good substitute. (A) Excluded anions can be measured in a regime that is independent of pH for a 24-bp DNA duplex (I 20 mM Na+ with 10 mM cacodylate and II 1 mM Mg + 20 mM Na+ with 10 mM cacodylate). (B) The calculated number of excluded anions (see Eq. (18.2)) does not depend on the fractional abundance of cacodylate for three ionic conditions (O) 20 mM Na+, ( ) 100 mM Na+, and (0) 1 mM Mg and 20 mMNaf Lines are least-squares linear fits. Total excluded anions per DNA are calculated according to Eq. (18.2) and are plotted above the main plot with the same symbols. Reprinted from Bai et al. (2007).

BASIC, or Beginners Algebraic Symbolic Instruction Code, was developed by Kemeny63 as a "baby FORTRAN" for simple computers (e.g., minicomputers). BASIC does not wait for the whole user-written program to be finished, but compiled each typed line as soon as typed. It was ideally suited for a simple learning environment. Microsoft VISUAL BASIC is a GUI-interfaced version. Microsoft QUICK BASIC 4.5 is much better than FORTRAN embodiments in accessing instruments for real-time data acquisition and control. 

From High Resolution NMR Spectra Catalog, Varian Instruments, Palo Alto, CA, 1963. The symbol m indicates a multiplet, several close lines that are not completely resolved. 

Figure 6.20 (a) Viscosity of solution of poly(y-benzyl-L-glutamate) (PBLG molecular weight 231,000), in m-cresol as a function of shear rate at 29 C for various mass percentages ranging from dilute ( 0.31%) to semidilute (0.31-2.5%) to concentrated isotropic (5-9.5%). The different symbols and lines refer to data taken on different instruments, (b) Zero-shear viscosity as a function of concentration, (reprinted with permission from Mead and Larson, Macromolecules 23 2524. Copyright 1990 American Chemical Society.)... 

Fig. 3 Box-plot of MTBE concentrations found in the vicinity of an airport (A) at different water bodies and (B) detailed for coastal water samples ( = 8) through seven sampling campaigns. For each variable, the box has lines at the lower quartile (25%), median (50%), and upper quartile (75%) values. The whiskers are the lines extending from each end of the box to show the extent of the data up to 1.5 times the interquartile range (IQR). The mean value is marked with (a) and outliers with (x) symbols. Each sample ( ) was analyzed in triplicate, and the average value was considered for calculations. Non-detected levels were expressed as half of instrumental limit of detection (5 X 10 rgL )...

In addition to spectra obtained with a Varian XL-300 spectrometer, proton spectra were acquired with a JEOL FX-400 spectrometer (400 MHz), and carbon spectra were acquired with a Varian FT-80 spectrometer (20 MHz). Spectra of solids were obtained with a Varian WL-112 spectrometer, which is a wide-line instrument that uses sinusoidal field modulation with detection via a lock-in amplifier (13C at 15 MHz and 2H at 12 MHz). (The symbol 8 denotes parts-per-million downfield from tetra-methylsilane.)... 

The nomenclature used for instrumentation is more complex than for equipment and process lines. Walker (2009) provides a list of commonly used instrument symbols. Typically an instrument balloon on a P ID contains two or three letters followed by five digits. So PI-30012, for example, identifies a pressure indicator number 12 in Section 30. 

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