Automatic sample inlets

Press Start. Add the measured water to the titration vessel by piercing the septum in the sample inlet port with the needle of the syringe and pushing the plunger all the way in. Remove the syringe from the sample port. Type in the sample weight on the keypad and press enter. The water will now be titrated by the automatic addition of titrant. At the completion of the titration, read and record the titer on the display. 

Mallet et al. [174] used an automated gas chromatographic system which consisted of a gas chromatograph mounted with an automatic sample interfaced to an integrator. A Melpar flame photometric detector (phosphorus mode) was connected with the flame gas inlets in the reverse configuration to prevent solvent flame-out. The detector was... 

The Dohrmann DN-1000 can be converted to the determination of sulfur and chlorine by adding the MCTS 130/120 microcoulometer detector modules. The control module, furnace module, and all the automated sample inlet modules are common to both detectors. The system automatically recognises what detector and sample inlet is present and sets the correct operating parameters for fast, simple conversion between nitrogen, sulfur, and chlorine detection. 

Since automatic samplers generally include an inlet tube, the development of problematic biological films within the tube and control unit can arise. The influence of automatic sampling equipment on biological oxygen demand (BOD) test nitrification in nonnitrified final effluent has been evaluated [45]. Samples were tested for BOD, carbonaceous BOD,... 

Small variations in apparent isotope ratio are observed when inlet pressure changes. Therefore IRMS dual inlet systems are equipped with bellows mechanisms (Fig. 7.9) so that inlet pressures of both sample and standard can be adjusted to be the same. Furthermore, small systematic changes, if any, in the measured isotope ratio as the measurement progresses are compensated by appropriate interpolation. Both these corrections are handled automatically by the software which controls the modern IRMS. 

Gas chromatograph systems are composed of an inlet, carrier gas, a column within an oven, and a detector (O Figure 1-1). The inlet should assure that a representative sample reproducibly, and frequently automatically, reaches the column. This chapter will cover injection techniques appropriate for capillary columns. These include direct, split/splitless, programmed temperature vaporization, and cool on-column injection (Dybowski and Kaiser, 2002). 

All samples and eluents must be filtered to prevent obstruction of flow through the system, especially at inlets to the columns. For manual injection 1-2 mL of sample are required to assure good rinse of the injection loop. For automatic injection, as with the WISP autosampler, the amount of sample required is relatively less since only the volume injected is actually used. 

Air permeability has also been used to determine the surface area of cement [41]. A porous piston compresses the sample of cement into a cell. Air is passed through a bottom porous plate, through the sample and porous piston, into the atmosphere. The inlet pressure is automatically adjusted and recorded to give a known air flowrate and the surface area is evaluated from the inlet pressure. The cell is emptied automatically becoming ready for the next test. 

The injector, which is the sample s entrance to the chromatograph, has different functions. Besides its role as an inlet for the sample, it must vaporize, mix with the carrier gas and bring about the sample at the head of the column. The characteristics of the injectors, as well as the modes of injection, differ according to column type. The use of an automatic injection system can significantly enhance measurement precision. 

This automatic classification is based on the value of the coefficient contribution of the reference spectra used in the semi-deterministic method (see Chapter 2). The reference spectra are related to suspended solids, colloids, dissolved organic compounds, surfactants and nitrate. For the determination of the coefficient values, an important experiment has been carried out [17], The deconvolution procedure was applied, on one hand, to several raw or treated samples taken at the inlet and outlet of several hundreds of waste-water treatment plants of different types, and, on the other hand, to a lot of surface water samples polluted with treated wastewater discharges. Table 5 shows the coefficients of the reference spectra for some of these samples (the coefficient values correspond to samples without dilution). The interpretation of the coefficients can lead to a rapid characterisation of the effluent type (inlet or outlet) and of the treatment plant type (chemical, biological, etc.). 

Figure 3.6 Pipette tip aligned and sealed around the inlet to a nozzle of the ESI Chip using the NanoMate system that automates nanoelectrospray infusion. Spray voltage and backing pressure are optimized based on the solution solvent composition to obtain a stable spray. The NanoMate system loads a new sample into a new pipette tip and automatically positions it to a new nozzle. The chip is automatically moved to the optimized spray position.

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