Abstract: The design of a new radiotelemetry capsule (26 mm long X 7.6 mm diameter), with an in vivo life of 1 month is described in the context of previous work in this field. In vitro evaluation of the capsule indicates an accuracy and performance comparable with a conventional pH meter. Several clinical applications are described, including measurements of gastrointestinal pH in humans and the measurement of extracellular pH in laboratory animals.

Abstract: A combined pH- and pressure-measurement device for oesophageal investigations has been designed using monocrystalline antimony pH electrodes and perfused polyvinyl catheters. The combined device facilitates pressure measurements simultaneously with pH recording, both distal and proximal to the pH electrode. The device is easier to pass through the nose to the oesophagus than the conventional glass pH electrode. pH and pressure measurements in the oesophagus are therefore simplified and valuable information about the function of the region of the lower oesophageal sphincter is added owing to the simultaneous recording of the two parameters.

Abstract: Continuous intra-arterial pH-monitoring was performed on anaesthetized and artificially ventilated dogs. The pH sensor consisted of monocrystalline antimony. The sensor was placed on the tip of a catheter, length approximately 35 cm and diameter 0.8 mm. No anticoagulation was undertaken. The pH range studied was 7.01-7.53, the pH being changed by infusion of sodium bicarbonate ro ammonium chloride. Arterial reference blood samples for in vitro blood gas analyses were taken under stable monitoring conditions and analysed with a minimal delay. The millivolt signal from the antimony sensor was found to be a linear function of the pH of the reference blood samples in the intra-arterial pH range studied. The sensitivities of the different antimony sensors were closely correlated but not identical. When the antimony sensor was used completely uncalibrated, the standard deviation of the registered potential corresponds to 0.06 pH units. After single point calibration a standard deviation of 0.03 pH units was obtained. These standard deviations include a suspected influence of minor changes in the partial pressure of oxygen during the experiments.

Abstract: An assembly for mounting a pH probe in a flowing solution, such as a sanitary sewer line, which prevents the sensitive glass portion of the probe from becoming coated with grease, oil, and other contaminants, whereby the probe gives reliable pH indication over an extended period of time. The pH probe assembly utilizes a special filter media and a timed back-rinse feature for flushing clear surface contaminants of the filter. The flushing liquid is of a known pH and is utilized to check performance of the probe.

Abstract: Publisher Summary This chapter describes a method for the measurement of hexose monophosphate shunt activity and oxygen uptake. The estimation of glucose oxidation via the hexose monophosphate shunt relies on the ability of the cell to oxidze preferentially [1- 1 4 C] glucose over [6- 1 4 C] glucose to 14 CO 2 . To prepare the working buffer, 100 ml of the concentrate is diluted with 850 ml of deionized water and the pH adjusted to 7.4 by the dropwise addition of 10 N NaOH, using a magnetic stirrer and pH meter. The concentrated buffer is made up at pH 5.0 to avoid the precipitation of magnesium and calcium salts; it is imperative to adjust the pH in dilute solution. Zymosan is employed as a phagocytic stimulus because it has been generally observed that it is more avidly phagocytized and yields a greater degree of respiratory burst activity than other particles. The reaction is initiated by the addition of cells and a center well containing 0.50 ml of hyamine hydroxide is simply placed inside the flask.

Abstract: PURPOSE:To realize a simple analysis for the components with a small amount of blood gathered and with no split of the sample, by securing a successive circulation of the blood from the measuring device for the blood pH and gas through the dialyzing device for the electrolyte measuring device and the dialyzing device for the biochemical component measuring devic each. CONSTITUTION:The sample liquid 2 which is held between the standard samples 1 and moving in the form of a band enters the measuring part 20 for the blood pH and gas. Thus the potential difference to the reference electrode 8 is measured through the pH electrode 5, P02 electrode 6, the PC02 electrode and the electrode 8 each, and then each concentration is obtained from the potential difference. Then the liquid 2 enters the dialysis cell 30, and the buffer solution 24 sampled the low molecular weight component in the liquid is led to the electrolyte measuring part 21 where each ion concentration is measured. The liquid 2 passed through the cell 30 is led to the dialysis cell 31, and the buffer solution 25 sampled the low molecular component is led to the enzyme reaction applied biochemical component measuring part where the glucose measurement part 22 and the urea nitrogen measuring part 23 are distributed in series. Thus the biochemical component concentration is measured.

Abstract: PURPOSE:To enable the continuous operation of a water film type electrical dust precipitator by injecting basic liquid into the dust-collecting water which is flowing in the dust-collecting water circulation line of the electrical dust precipitator and aerating the water in the circulation line part, thereby controlling the pH of the dust collecting water and SO3 concn. CONSTITUTION:When the pH value of the water of a dust-collecting water circulating line 3 falls below 6, a valve opening signal is sent from a pH meter 6 to a valve 7a for a predetermined time, during which the valve is held open. A predtermined amount of alkaline liquid (e.g.; aqueous NaOH soln.) 7b is injected through this valve 7a into the circlating line 3, so that the pH of the water is controlled to therein is decreased. Using this air at the amount 3-5 times the theoretical amount for oxidizing SO2 to SO3 suffices. Since the SO2 absorption amount of the case of a water film type electrode is about 4%, the effect thereof in provided by the aeration of an extremely small amount of air.

Abstract: We have made continuous pH measurements of plaque grown between teeth in the Orofax artificial mouth system (Bibby, B.G. and Huang, C.T., J Dent Res, In press). For the present tests, two half-teeth were mounted in wax to form an approximal space, through one tooth, a miniature glass electrodes was set flush with the enamel surface. It was connected through a field-effect transistor amplifier (FET) to a millivolt/pH metert and paper chart recorder using a small flexible Ag/AgCl reference electrode.0 The pH electrode was calibrated in phosphate buffer at pH 7 and pH 4. To grow plaque, the interproximal area was inoculated with a sonicated suspension of human plaque; it was then placed under the flow of saliva and re-inoculated four and eight h later. On the second day plaque development was enhanced by adding a 35-mg sucrose-corn starch tablet three times at intervals of four h. Plaque three to eight days old was tested. Between tests and each night the plaque was kept in the flow of saliva. The electrode calibration was checked daily. Most tests were made by stopping the flow of saliva and adding 0.1 ml of a 2% solution of a sugar, starch, sorbitol, or xylitol to the approximal area. Thereafter a drop of saliva, water, or substrate was added every 30 min to prevent drying, and the pH was observed until a pH minimum was reached. If tests were made while saliva continued to drop, the pH depressions were smaller and of shorter duration. To restore the pH to the starting level, 0.1 ml of 1% carbamide was added, and the flow of saliva was allowed to run for 60 min to wash out excess substrate and carbamide. Very little acid production was evident with sorbitol addition. Lactose gave a pronounced pH drop, reaching a pH minimum of 4.4 after 65 min. Sucrose and several starches gave closely comparable results. The pH decreases were more rapid than with lactose and reached a stable level of pH 3.5 after 50 min. It is interesting that potato starch, which had been partly hydrolyzed by boiling, is as acidogenic as sucrose in this system. Gram-stained smears on the third and eighth days showed a mainly gram-positive coccal flora with some gram-negative and sarcinal types,

Abstract: PURPOSE:To obtain a diaphragm-coated electrode which is suited for analysis of materials having an amount as small as to make stirring difficult, or highly viscous materials or those which make measurement inconvenient when stirred by providing a vibrating mechanism that gives microvibrations to the electrode. CONSTITUTION:A vibrating mechanism 2 is provided by the fixing a small-sized vibrator or the like by means of a rubber band or by doing others to a diaphragm- coated electrode, such as a composite pH electrode or solid electrode coated with a gas permeable membrane, which measures components such as dissolved CO2, sugar, amino acids and others in the specimen liquid by using the diaphragm coating, and the sensing part 3 of the electrode 1 is vibrated at amplitudes of a 0.1-2mm. range. In this way, the electrode is made suitable for analyzing of specimen liquid which is too small in amount to permit stirring or flowing, semisolid specimen liquid which is highly viscous and requires powerful stirring power, or specimen liquid which causes such inconveniences as escaping of dissolved gases into the atmosphere or conversely taking these into the liquid when stirred.

Abstract: The development of an inexpensive microcell for pH measurement is described. The cell can be used for sample volumes of 50–200μl. Its main advantages are the easy replacement of both the diaphragm and the pH glass membrane at low cost. The reproducibility with a conventional pH meter is ±0.01 pH unit, but can be improved to ±0.004 pH unit by differential measurement.

Abstract: PURPOSE:The titled perfuser in which a pH meter and a double roller pump are equipped and the pH and pressure of the perfusate are automatically controlled to prevent the decomposition of the organ and keep the storage coditions, best, resulting in great increase of the storable period of the organ. CONSTITUTION:An eviscerated organ 2 is placed in the storage tank 1 and one end of circulation path 4 is connected to storage cannula. Artificial lung 5, double roller pump 7, heat exchanger 8 and other devices are made to operate so that the perfusate is kept at a prescribed temperature and circulated by the action of pump 7 in the arrow direction to store the organ 2. The pH meter 9 measures the pH of the perfustate, and if the pH is high, magnet valve 16 is opened by the action of pH controller 14 to increase the supply of carbon dioxide gas to the artificial lung 5. On the contrary, if the pH is low, magnet valve 17 is opened to increase the amount of oxygen gas, thus controlling the pH to the prescribed value. Further, according to the values measured by pressure meter 23, the rotation of motor 17 is controlled by the action of pressure controller 20 to adjust the flux of the perfusate.

Abstract: PURPOSE:To efficiently provide a titled crystalline zinc hydroxide by a method wherein aqueous zinc salt solution and alkali neutralizing agent are continuously supplied to react with each other into a reactor previously maintained at a specific pH and temperature condition. CONSTITUTION:Neutralizing solution more than 10.5 of pH is charged in a neutralization reactor tank 1 having a stirrer 2 which is maintained at a constant temperature less than 35 deg.C by use of a thermister 11 detecting the temperature in the reactor 1 and a heater 13 actuated by a proportional controller 12. Into the tank 1, each specific amount of zinc salt solution 3 and neutralizing agent 4 are continuously added through tube pumps 5, 6. In the tank, a pH meter 7 measures pH and a coupled proportional controller 8 controls pump 6 of neutralizing agent 4. Precipitate-contg. liquid overflowed the tank 1 is aged in a aging tank 9 for a short period of time, then is recovered into a reservoir 10 as product. Preferably, the zinc salt used is inorganic salts contg. one or more of SO4 , Cl2 , and (NO3 )2, and alkali neutralizing agent is one or more of NaOH, NH4OH, and NH3.

Abstract: Schofield(l) in 1955 introduced the concept of “lime potential”, i.e., pH-0.5pCa. Since then, some papers have been published on the factors affecting its determination. For the calculation of pCa the generally used method is to analyse chemically the Ca concentration in the solution and then compute in terms of the activity coefficient. By this method it is inevitable to subject to some errors due to the uncertainty in the calculation of single ion activity, to say nothing of the tediousness in analytical operations. Krupsky(2) determined the pH and pCa with a glass pH electrode and a calcium—selective electrode respectively. But the use of a reference electrode may still cause some errors due to the troublesome liquid—junction potential when the salt bridge is in contact with the charged soil particles.

Abstract: PURPOSE:To raise the efficiency of deodorization and reduce the operating cost of deodorizer by a method in which ozonized air is injected into the bottom liquid of a cleaning tower to oxidize offensive odor components in the liquid by ozone and the neutralization of the overflow of the bottom liquid is performed by regulating the pH of the bottom liquid. CONSTITUTION:Offensive odor gas 1 is treated sequentially by an acid washing tower 4, a demister 19, and an alkali washing tower 5 and then released as a treated gas 3. And, a pH meter 8 is provided for a waste water storage tank 14 for neutralizing the pH of mixed waste water 20 of overflows 15 and 16, and the pH of the bottom liquid 31 of the acid washing tower 14 is controlled by injecting sulfuric acid 6 by a chemical injection pump 10 interlocking with the pH meter 8. Then, caustic soda 7 is injected by a chemical injection pump 11 interlocking with a pH meter 9 for the bottom liquid to regulate the pH of the bottom liquid 32 in the alkali washing tower, while the bottom liquid is circulated and diffused into packings 18 by circulating pumps 13 and 12. On the other hand, O3 is supplied through diffusers 33 and 34 from an ozonizer 17 to the bottom liquid to oxidize and decompose offensive odor components dissolved in the bottom liquid.

Abstract: A small flexible pH-electrode was developed for monitoring the esophageal pH of small infants (Fig. 1). The sensing part of the electrode consists of a 1.3 mm diameter pH glass hemisphere sealed onto a 1.3 mm glass tube. The total length of the glass electrode is 6 mm. A pH buffer with a Ag/AgCl internal reference electrode is completely glass sealed around a platinum pin and attached to the center core of a low-noised miniature coaxial cable. The outer sleeve of the coaxial cable is pushed out over the glass stem. A silicone rubber is used to insure a good, flexible water-tight seal around the glass.