Sampling timer

Sample timer setting means increments as small as 0.1 secs... 

A more permanent installation is provided by a chain-driven sampler, widely used in paper (qv) and steel (qv) mills, manufactured as the E Sampler by QCEC (20). A cup, which is attached to a chain positioned perpendicular to flow, travels down through the Hquid flow and returns to the upper sprocket, where the sample is drained into a container. Flow-proportional timers can be installed to change the rate of sampling with flow rate (see Flow l asurel nt). 

The cost of an electric-drive rotaiy-cutter sample of the smallest size manufactured—suitable for gravity sampling of fine particulate solids or shiny flow—including timer and control unit was approximately 5,000 in 1996. 

Electronic Flow Calibrators These units are high accuracy electronic bubble flowmeters that provide instantaneous air flow readings and a cumulative averaging of multiple samples. These calibrators measure the flow rate of gases and report volume per unit of time. The timer is capable of detecting a soap film at 80... 

NC samples were irradiated for 3 min and TNT and HMX for 1 min at a 14 MeV neutron flux of approx 108n/cmasec, Simultaneous counting was performed by means of a matched dual 7.6x7.6cm flat Nal crystal detector assembly in conjunction with a Kaman Nuclear programmed timer system for automatic sample transfer, A one-min count time was usually sufficient to exceed 10 counts. The signal from each de-... 

Quantum yields of photodegradation were measured using an automatic viscosity timer modified so that the samples could be irradiated and deaerated in situ. 

Automatic analysis consists essentially of the same steps as the corresponding manual method (p. 4). In some cases this may be simple, the requirements amounting to a mechanical device for presenting the sample to the detector, a timer to control the time of measurement and a data recorder. However, if sample pretreatment and separations are necessary a variety of wet chemical stages needs to be automated. Such automated steps may be included in what remains essentially as an operator procedure. For... 

Set a timer for five minutes. Draft a thesis statement and create an outline for the following sample SAT essay prompt ... 

Gather a couple of sample prompts online or from other books about your exam (see the Additional Resources section for a list of books and online resources). Set the timer for five minutes and practice writing thesis statements and outlines. The more you practice, the easier it will be to plan your essay on exam day. 

A schematic diagram of the automatic system is shown in Fig. 4.12. It consists of five component modules a sample introduction unit, a digestion unit, a neutrafization vessel, a chelation and extraction vessel and an extract collection unit. The sy stem is controlled by a series of interacting cam and electronic process timers. 

The system control is based on a series of six cam timers, which control the following sample introduction unit, sampling phase sample introduction unit, refilling phase neutralization unit, neutralization phase neutralization unit, wash phase chelation— extraction unit, extraction phase and chelation—extraction unit, collection and wash phase. 

Figure 5.19 — Flow-through biochemical sensor based on the twofold immobilization of the catalyst (urease) and reagent (an acid-base azo dye) in the sensing microzone for the determination of urea in kidney dialysate. (A) Sensing microzone held in a microcircuit. (B) Valveless flow injection manifold. P pumps T timer S sample W waste. For details, see text. (Reproduced from [57] with permission of Elsevier Science Publishers).

Urea in kidney dialysate can be determined by immobilizing urease (via silylation or with glutaraldehyde as binder) on commercially available acid-base cellulose pads the process has to be modified slightly in order not to alter the dye contained in the pads [57]. The stopped-flow technique assures the required sensitivity for the enzymatic reaction, which takes 30-60 s. Synchronization of the peristaltic pumps PI and P2 in the valveless impulse-response flow injection manifold depicted in Fig. 5.19.B by means of a timer enables kinetic measurements [62]. Following a comprehensive study of the effect of hydrodynamic and (bio)chemical variables, the sensor was optimized for monitoring urea in real biological samples. A similar system was used for the determination of penicillin by penicillinase-catalysed hydrolysis. The enzyme was immobilized on acid-base cellulose strips via bovine serum albumin similarly as in enzyme electrodes [63], even though the above-described procedure would have been equally effective. 

When requested by the user located at the point of use, the first exchanger on the secondary loop starts to cool the water. This one is automatically heated at minimum 85°C before the return in the primary loop. When the temperature asked for the cold point of use is reached, the sampling value is automatically opened. The users ask to stop the sampling. A safety timer must be installed to prevent the draining of the installation. Safety timing is adjustable (maximum 1 h) temperature of cold point 30°C 5°C. 

A colorimeter (Figure 4) has been designed specifically for analyzing >2/ ) passive samplers. It is lightweight, portable and simple to use. Features incorporated into the unit include a ten-minute timer with audible alarm to ensure complete color development of the samples before analysis, a cuvette slot which... 

A1-liter polyethylene bottle was used for the extraction studies. A small amount of butane (approximately 0.2 g) of butane was bled into the bottle. The bottle was capped and a 2-ml sample was withdrawn by inserting a syringe needle through the side. Hie sample was then injected into a gas chromatograph. The timer was started and a chromatogram recorded. Samples were taken for 2 h to ensure that the butane was not affected by the bottle. Figure 4.11 depicts the result. 

Figure 1. Block diagram of single-photon time-correlation apparatus from Barker and Weston 11 HV, high-voltage supplies L, lamp PI, photomultiplier M, monochromator FURN, furnace C, sample cell LP, light pipe F, interference filter P2, photomultiplier AMP, amplifier DISCI, discriminator D1SC2, discriminator T-S, timer scaler DL, delay line TAC, time-to-amplitude converter BA, biased amplifier MCPHA, multichannel pulse-height analyzer TTY, teletype printer and paper-tape punch REC, strip-chart recorder.

Use a 10-ml or 10-pl gas-tight syringe to inject 5 ml headspace gas or 1 pi solvent extract, or insert an SPME fiber containing the sample, and start the program. Start a timer immediately after injection. 

The sample is loaded onto the instrument and the time reference is noted by starting a timer or resetting a timer in the software. A dynamic test for viscoelastic structure is then used to monitor changes in the sample that could result from mechanical relaxation, drying, or thixotropy. A time sweep test is usually performed at a constant temperature. The test is also run at a constant frequency that is comparable to real-time observation (typically 1 Hz) or at a constant angular frequency (10 rad/sec or 1.6 Hz). 

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