Single instruments

The first 3 items of the above list (waveguides, transducers and preamplifiers) are located at or near to the component(s) to be monitored. The other items must be installed in the control room area, mounted into a single instrumentation rack (fig. 4). 

The presence of surface conductance behind the slip plane alters the relationships between the various electrokinetic phenomena [83, 84] further complications arise in solvent mixtures [85]. Surface conductance can have a profound effect on the streaming current and electrophoretic mobility of polymer latices [86, 87]. In order to obtain an accurate interpretation of the electrostatic properties of a suspension, one must perform more than one type of electrokinetic experiment. One novel approach is to measure electrophoretic mobility and dielectric spectroscopy in a single instrument [88]. 

A single instrument — a hybrid of a quadrupole and a TOF analyzer — can measure a full mass spectrum of ions produced in an ion source. If these are molecular ions, their relative molecular mass is obtained. Alternatively, precursor ions can be selected for MS/MS to give a fragment-ion spectrum characteristic of the precursor ions chosen, which gives structural information about the original molecule. 

Reproducibility (especially within a single instrument)(Refs. 18 19)... 

Principles and Characteristics In an attempt to develop a unified sample preparation system for extraction of various matrix/analyte combinations Ashraf-Khorassani et al. [498] have described a hybrid supercritical fluid extraction/enhanced solvent extraction (SFE/ESE ) system to remove both polar and nonpolar analytes from various matrices. The idea is that a single instrument that can perform extractions via pure C02 solvent, and all gradients thereof affords... 

Le Bourdon, G., Adar, F., Moreau, M. et al. (2003) In situ characterization by Raman and IR vibrational spectroscopies on a single instrument deNO, reaction over a Pd/y-Al203 catalyst, Phys. Chem. Chem. Phys., 5, 4441. 

Numerous other FOCS schemes have been described for heavy metals in the past 20 years (for reviews, see 113-115). In looking at the more recent literature one may state, however, that some of the newly described "chemistries" perform hardly better than the rather old commercial systems based on the use of dry reagent chemistries, with the additional advantage that they are compatible with a single instrument for read-out. In fact, some of the newer systems involve rather extensive chemistry and - worst of all -seem to strongly differ in terms of spectroscopy and analytical wavelengths so that they all require their own opto-electronic platform. On the other hand, there is substantial need for (low-cost) sensors for less common... 

Systems are designed to function normally even when a single instrument or control function fails. This is achieved with redundant controls, including two or more measurements, processing paths, and actuators that ensure that the system operates safely and reliably. The degree of redundancy depends on the hazards of the process and on the potential for economic losses. An example of a redundant temperature measurement is an additional temperature probe. An example of a redundant temperature control loop is an additional temperature probe, controller, and actuator (for example, cooling water control valve). 

MS offers the opportunity for both qualitative and quantitative analysis in a single instrument and even in a single experiment. In full-scan mode, mass spectra are continuously scanned as the gas chromatographic analysis proceeds. As shown in Fig. 14.8, GC/MS provides a three-dimensional data set with axes of time, mass-to-charge ratio and... 

Repeatability The closeness of a set of measurements carried out by a single analyst on a single instrument within a narrow time-interval using the same reagents. 

The microwave source used in this study was a microwave network analyzer model IFR 6845 shown in Fig. 15.2b (Microwave network analyzer). Integrated into this single instrument is a synthesized source, a three-input scalar analyzer, and a synthesized spectrum analyzer. Complete engineering details of this equipment is beyond the scope of this document, but the basic function of this instrument is to generate a constant... 

Commercial instruments have a reasonable balance between the recommended column size and the volume of the column and connecting tubing (XY). However, the theoretical plate number of a single column may give different values on different instruments, and even on replacement of the components and parts of a single instrument. Such discrepancies can be understood in terms of differences in the mechanics of the instruments and the design of their parts. 

Because of its versatility and complexity CE should be regarded as a family of analytical techniques that are performed on one single instrument, rather than a single technique. Each... 

Find three articles that describe a single Instrument that you have used. Compare the parameters reported in each article. 

It is a truism that no matter how sophisticated the diagnostic instrument, nothing can replace a well-conducted comprehensive clinical interview. It is essential in the assessment of pediatric PTSD that clinicians use multiple informants and take careful histories while searching for complicating comorbid conditions. No single instrument will serve all clinicians. 

Simultaneous Thermal Analysis (STA) A technique which combines DTA, TGA, DSC (cal.) and derivatives of DTA/TGA in a single instrument, offers advantages over the performance of each technique as a separate experiment on stand-alone instruments. By examining a single sample, one ensures no variation in sample homogeneity, atmosphere difference and other instrumental parameters. At the same time, there is a provision for detection and analysis of evolved gases (EGA) during thermal decomposition. Also, derivatives of TGA and DTA can be precisely measured (electronically). 

Strictly speaking, Equation (2) allows the vertical component of surface tension to be measured. Since this equals 7 cos 0, we are actually making a single measurement that involves two parameters. If 7 were independently known, the Wilhelmy plate method could also be used to determine 0. Whether we seek to evaluate 7, 0, or both, two experiments are needed, and these may not both involve the factor cos 0. In Section 6.8a we discuss a second type of measurement that can be made with the Wilhelmy apparatus that supplies a complementary observation so both 7 and 0 can be determined on a single instrument. 

As with other techniques, a single instrument is usually not sufficient for full analysis of organophosphorus residues. HPLC is often combined with other instrumental methods, mostly GLC, TLC or mass spectrometry. A recently suggested procedure for the analysis of residues found in potatoes requires the use of three different HPLC and three different GLC instruments for the study of one sample183. 

The overall simplicity of an FT-IR compared to a dispersive instrument is also an advantage. For example, a single instrument can be easily converted to study the near, mid or far-infrared frequency region whereas with the dispersive method, three totally different instruments are required. To improve resolution with an FT-IR instrument, the basic design is only slightly modified while for a dispersive instrument different optical components are required. 

In the condensed phase, due to interactions of molecules with neighbouring species, no single instrument, regardless of its resolution, can record a spectrum in which individual transitions are seen. In the best case for simple molecules, fine structure corresponding to envelopes of transitions can be observed (Fig. 11.1). 

The column is the heart of the chromatograph and provides versatility in types of analyses that can be obtained with a single instrument. This versatility is due to the wide variety of column materials available, but can also be a problem when it comes time to choose appropriate materials. The purpose of this chapter is to provide the reader with a basic understanding in the composition and use of columns. 

In many chromatographic analysis, the length of the elution time greatly restricts the number of runs that can be performed in any working day on a single instrument. The number of runs in a single day can be increased by ... 

Multiple thermocouples may be used in parallel and connected to a single instrument. A typical application is a tire-warning system. Multiple... 

In early 1983, Bioanalytical Systems introduced a new class of integrated processor-driven instrumentation based on a concept first developed by Faulkner and his co-workers [1] at the University of Illinois. This unit (Figs. 6.22 and 6.23) has evolved over the years and now includes a repertoire of some 35 electrochemical techniques, including the most popular large-amplitude (Chap. 3) and small-amplitude (Chap. 5) controlled-potential methods. The unit also is capable of determining electrocapillary curves and can automatically measure and compensate for solution resistance (R in Fig. 6.5). Thus in a single instrument it is possible to utilize virtually all of the diagnostic criteria introduced in Chapters 3 and 5 and also to explore quickly which technique is optimum for... 

The coefficient of variation for data from a single instrument should be <5% and for data... 

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