Continuous determination

A mechanics-free airborne sound location system is used in order to record the probe movement and the rotation direction of the probe relative to the weld. Two airborne sound transmitters are arranged on the probe holder and two receivers are fixed on a 50 cm long rail equipped with two magnetic pads The exact probe position and rotation direction is continuously determined by system. 

Figure 1. Apparatus for the continuous determination of the carbon dioxide emission from a paint layer during curing.

Offenbacher H., Wolfbeis O.S., Ftirlinger E., Fluorescence optical sensors for continuous determination of near-neutral pH values, Sensors Actuat. 1986 9 73. 

Lobnik A., Cajlakovic M., Sol-gel based optical sensor for continuous determination of dissolved hydrogen peroxide, Sensors Actuators B 2001 74 194-199. 

The continuous determination of compounds, which may adversely affect ecosystems and/or human health, is a major regulative and legislative goal of environmental protection nowadays. Considering the costs and efforts related to this task corroborates a clear demand for portable, real-time, in-situ, field applicable and cost-effective monitoring techniques. Due to their inherent properties, vibrational spectroscopic sensors, in particular fibre-optic sensors show a high potential to contribute to these applications. 

The detection and alarm circuits of fire and gas detection systems should be continuously supervised to determine if the system is operable. Normal mechanisms provide for a limited current flow through the circuits for normal operation. During alarm conditions current flow is increased while during failure modes the current level is nonexistence. By measuring levels at a control point the health of the circuit or monitoring devices can be continuously determined. End-of-line-resistors (EOLR) are commonly provided in each circuit to provide supervisory signal levels to the control location. 

The acid-oxidant method is based on the idea that the hydrolysis of cellulose might be continuously determined from the rate of carbon dioxide evolution. Since, under controlled conditions, the rate of evolution of carbon dioxide is proportional to glucose concentration, it should be possible to follow the course of cellulose hydrolysis by means of the rate of carbon dioxide evolution provided that the sole final product of hydrolysis of cellulose is glucose. The latter assumption appears to be justified where the sample is reasonably pure. 

E. Urbano, H. Offenbacher, and 0. S. Wolfbeis, Optical sensor for continuous determination of... 

Denis M, Minon G, Masschelein WJ. 1989. Continuous determination of residual chlorite in water. Anal ChimActa 226(1) 121-128. 

A method for continuous determination of ionization wave propagation was developed (See Refs 9 11)- Basically the system uses a linear resistance element that is imbedded in the chge and usually positioned on the axis where chge symmetry will provide interactions of the greatest magnitude. In its... 

Johnson, K.S., C.M. Sakamoto-Arnold, and C.L. Beehler. 1989. Continuous determination of nitrate concentrations in situ. Deep-Sea Res. 36 1407-1413. 

Immobilized whole cells of Pseudomonas fluorescens were used for the glucose sensor. The microbial sensor has been applied to the continuous determination of glucose in molasses. 

Cephalosporin is determined from the proton concentration generated in a medium by using immobilized bacteria. A microbial sensor composed of a bacteria-collagen membrane reactor and a combined glass electrode was applied to the determination of cephalosporins in fermentation media. The system used for continuous determination... 

Dilute CO elimination from air has been rapidly evaluated using CO gas sensors [25, 26]. The oxidation of 1 vol% CO in air was carried out under atmospheric pressure from 30 to 150 °C with a ramp rate of 2°C min-1. The CO concentration of an effluent from the reactor was continuously determined by the CO gas sensor. Fig. 8.1 shows the output signal and CO conversion determined by the CO gas sensor, and the CO conversion determined by FID-GC, for CO oxidation over Rh/Ti02. This indicates that the CO concentration decreases with increasing temperature, i.e., the CO conversion rate increases at higher temperature. The closed circles in Fig. 8.1 indicate the CO conversion determined by gas chromatography. The conversion curve calculated from the output signals of the CO gas sensor is... 

This article presents the design and implementation of a software sensor for the continuous determination of substrate concentration based on a simple model of a fed-batch fermentation process and the available signals of two other sensors—one for on-line biomass determination (7) and the other for on-line ethanol determination (8)—developed in previous works. The software sensor proposed provides a continuous signal that can be used in a control loop to manipulate the substrate feed flow in order to maintain almost constant substrate concentration and obtain an excellent level of productivity and yield during all of the process, as shown in experimental control strategy studies in previous works (9). 

Figure 7.3. Experimental set-up for the fully automated continuous determination of phenols. FID — flame ionization deteotor, GC — gas chromatography, IV1 — HPLC injection valve, IV2 — low-pressure Injeotlon valve, M — membrane, PC — personal computer, PL — propagating liquid, PP — peristaltic pump, PU — pervaporation unit, RC — reaction chamber, S — sample, UP — ultrasonic probe, W — waste and WB — water bath. (Reproduoed with permission of Springer-Verlag, Ref. [31].)...

A room is heated by a baseboard resistance healer. When the heat losses from the room on a winter day amount to 7000 kJA>. it is observed that the air lemperaiure in the room remains constant even though the healer operates continuously. Determine the power rating of the healer, in kW. 

The rate of electroless plating can be measured by several different methods, including nonelectrochemical techniques, such as those based on weight gain determination, electrical resistance measurement, and optical transmission measurement. The latter methods have been adopted to continuously determine plating rates for the purpose of process control. Electrochemical methods described below have also proven to be useful for automatic control of various electroless processes. 

Continuous determination of carbon monoxide and carbon dioxide in the flue gas, by means of an infrared gas analyzer, has been reported to be an effective method for operating control, as well as for calculation of yields (307). 

Kawazu, K., Fritz, J. S. Rapid and continuous determination of metal ions by cation-exchange-chromatography. J. Chromatogr. 77, 397 (1973)... 

The product gas is cleaned of char particles using a cyclone. The liquid products and water are retained in a system of two condensers and a cotton filter. The gas flow rate is then measured using a dry testmeter, and the CO and CO concentrations are continuously determined by an infrared analyzer. In addition, gas samples are taken at regular time intervals and analyzed by chromatography to determine the percentages of Hj. CO, CO2, CH4 and Cj (CjHi, CjH, CjHj) in the product gas. Reaction temperature. 

Balke, B., Continuous Determination of Nitrogen Concentrations during the Respira-... 

Steiner, M. and Lazaroff, N., 1974. Direct method for continuous determination of iron oxidation by autotrophic bacteria. Appl. Microbiol., 28 872—880. 

Nakahara T, Kawakami K, Tamotsu W. 1988. Continuous determination of low concentrations of mercury by atomic-emission spectrometry with helium microwave-induced plasma. Chemistry Express 3(11) 651-654. 

Urbano, E. Offenbacher, H. Wolfbeis, O. S. Optical Sensor for Continuous Determination of Halides. Anal. Chem. Abstract 1984, 56, 427-429... 

Applications. A cone calorimeter, named after a truncated cone shape of the furnace, is a heat release rate calorimeter which permits the determination of heat release under controlled conditions. It determines the critical fire parameters required for a range of natural and synthetic materials using small samples (100 mnL), and simple materials, and is used for composites and combinations of different materials. This apparatus allows simultaneous and continuous determinations of heat release rate, smoke production rate, mass loss rate, concentration of the various combustion gases formed, ignitability, heat of combustion and soot production data for the materials tested. 

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