An NOx concentration measuring apparatus employing first and second wide-range air/fuel ratio sensors for measuring an NOx concentration of gases introduced thereto through a first passage. First and second restricted orifices are provided in the first passage upstream of the first and second sensors. A second passage is connected to the first passage between the first and second orifices. A suction pump is connected to the first passage downstream of the first and second sensors for producing a...

Apparatus and method for controlling the toner concentration of developer mixtures in electrostatographic devices. Light is reflected from the developer and the light reflectance ratio is converted to electrical signals by a two-path circuit. Both the gain and offset of a circuit amplifier are controllable to allow for optimum response to carriers of different reflectivities. The gain is set depending upon the desired sensitivity and the offset voltage is set to establish the output voltage at a...

A toner concentration monitor includes a polarized dielectric member which, when dipped into a development mixture of carrier and toner particles, provides an accurate indication of the toner concentration of the mixture by the amount of toner particles which adhere to the member. The polarized dielectric member is preferably an electret.

An apparatus for determining the concentration of solids in suspension in a fluid. The apparatus comprises a source of light, a measurement chamber to contain a quantity of the suspension and to admit thereinto only a single beam of light from said source of light, a first photocell to receive light originating from said source of light and reflected through an angle of approximately 180.degree. by solid particles in the suspension and to produce a signal proportional to the intensity of the ref...

A feed solution containing a solute and a solvent is concentrated by reverse osmosis. The feed solution is subjected to a given working pressure and is first forced through a series of high rejection membranes. The diluted solution which permeates the high rejection membranes is discarded and the product solution leaving the high rejection membranes is then passed as a feed solution through a series of low rejection membranes. The dilute solution which permeates through the low rejection membran...

A system which provides digital readout representative of the transmittance, absorbance and concentration characteristics of a sample which has been analyzed by a spectromittance of the sample. The system can be selectively operated to show the desired characteristic of the sample in digital form. If the absorbance is to be displayed, the spectrophotometer output signal is fed through a circuit which provides a log function to convert the transmittance characteristic to an absorbance characteris...

Apparatus for concentration of a sample, to be delivered to a remote analysis mechanism, including a vertically mounted, quartz-lined heater, a water cooled condenser which is teflon-coated to eliminate cross-contamination and which has a sandwichlike construction to facilitate disassembly and cleaning, and an extended corrugated teflon tube for transporting the sample to the remote analysis mechanism.

The present invention provides a fuel cell comprising a fuel chamber and oxidizer chamber, an electrolyte chamber having electrolyte therein, the electrolyte chamber being hermetically sealed from the first two chambers by a first closed electrode separating the electrolyte chamber from the oxidizer chamber, and by a second closed electrode separating the fuel chamber from the electrolyte chamber. Each of the electrodes are composed of a material selectively permeable to only one of the cell rea...

An air concentrating nozzle is provided in a flat patterned body manufactured of light weight plastic or paper. The patterned body can be rolled into a cone and maintained cone shaped by inherent fasteners holding the edges together. In cone shape, a small opening at a first end concentrates air discharge and a large opening at a second end adapts the cone as a universal fitting for attachment over a majority of barrels used on home type hand-held hair dryers. An elastic loop attached to the air...

An oxygen concentration-sensing device has an oxygen concentration-sensing element which senses the concentration of oxygen contained in a gas, and a heater which heats the sensing element. A control device is electrically connected to the heater for controlling the supply of electricity to the heater so as to bring the temperature of the heater to a desired temperature. A coupler connects between the sensing element and the control device. A compensating resistance is accommodated in the couple...