ES&T PRODUCTS Smoke opacity system State-of-the-art remote sensing system determines the opacity of emissions external to the stack and calibrates in-stack transmissometers. This method, called light detection and ranging, is an EPA-approved alternate method to Reference Method No. 9. The system operates during the day or at night with an accuracy better than 3%. Computer Genetics 101
Low-pressure device Transmitter measures extremely low pressures down to fractions of an inch of water. It is available in full-scale gauge and differential ranges from 0-2 in. H 2 0 to 0-100 psi and in ab solute ranges from 0-50 in. FLO to 0-100 psi. The transmitter can also be used as a liquid level sensor to measure levels from 0-2 in. to 0-200 ft of liquid in either open or pressurized vessels. Schaevitz Engineering 102
Electronic recorders Two-channel, combination x-y/ strip-chart recorders have 0.05% ac curacy, full-scale ranges from 10 mV to 10 V, and speeds up to I in. per 2.5 ms. Analog voltage signals are auto matically digitized with 12-bit preci sion, stored, and plotted. Stored data can be processed and transmitted to a computer through an RS232C inter face. Bascom-Turncr Instruments 103 Peristaltic pump Variable-speed, dual-channel peri staltic pump for column chromatog raphy is designed for liquid-transfer procedures that require accuracy and reproducibility. An electronic speed controller allows flow rates to be varied during operation. Flow rates can be set from 0.6 m L / h to 325 m L / h by using different sizes of flexible tubing. BioRad Laboratories 104
Need more information about any items? If so. just circle the appropriate numbers on one of the reader service cards bound into this issue and mail ir the card. No stamp is necessary.
Air sampler controller Instrument provides selectable, winddependent control for Hi-Vol air samplers. Relay contacts turn sam plers on or off in relation to wind speed and direction. Alarm modules can be set to select the speed threshold and direction sectors of interest. The unit has analog displays of wind speed and direction as well as voltage outputs. Weathertronics 105 Strip-chart recorders Compact portable recorders are de signed for laboratory and field appli cations and are available in both 1 - and 2-channel models. Sixteen input ranges from ± 1 mV to ± 100 V can be selected with a rotary switch. Chart speed is also switch-selectable, with a choice of 13 speeds or external voltage pulse drive. Weather Measure 106 Mercury analyzer Microprocessor-controlled device uses a gold film sensor to measure the total mass of mercury in a sample. One push-button control automatically rezerocs the LCD meter, starts the internal pump, times a 60-s bubbling cycle, and displays the mercury read ing directly in nanograms. Full-range linearity allows for single-point cali bration checks. Jerome Instrument 107
Sampler for effluent streams Sampler collects liquids in digitally programmed proportions of the total volume passing through a system. Continuous proportional monitoring ensures no gaps in coverage. Ivek 108 Microbial air sampler Six-stage sampler collects airborne microorganisms and differentiates between respirablc and nonrcspirable particles. Acrodynamically sizes viable particles 7.0 μιη and above down to 0.65 μνη in six separate size ranges. Andersen Samplers 109
Strip-chart recorder Microprocessor-controlled unit has a reverse and forward chart drive. When a return control is activated, the paper is automatically rewound to the exact starting point of an analytical run, so that sequential sidc-by-side or super imposed runs can be made. Pen re sponds to very small signal changes. Linear Instruments 110 Microcentrifuge Compact benchtop model accepts up to sixteen 1.5-mL sample tubes. Ac cessory adapters permit use of tubes with 250-600 μ ι capacity. The cen trifuge accelerates to 13 750 rpm in less than 6 s. Fisher Scientific 111 Sterile bench A horizontal, laminar-flow station contains two filters and supplies Class 100 air that meets federal standard No. 209b. The fine filter removes 99.97% of all particles 0.3 μιη in size. The coarse Dacron prefilter pulls air through the top of the cabinet, trap ping large particles. A differential pressure gauge monitors the pressure across the fine filter, indicating the filter condition at all times. Labconco 112 Digital thermometer Portable thermometer has three large '/2-in. LCD digits and is designed for use with iron-constantan thermocou ples. It covers the range of —25 ° F to 500 ° F with 1% accuracy. A switch converts it from ° F to °C. A single 9-V battery supplies 500 h of continuous operation. Nanmac 113 Companies interested in a listing in this department should send their releases directly to Environmental Science & Technology, Attn: Products, 1155 16th St., N.W., Washington, DC. 20036 Environ. Sci. Technol., Vol. 17, No. 2. 1983
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Relative humidity instrument Instrument directly measures relative humidity with a high-strength phenolic probe containing a relative humidity sensor as well as a temperature com pensating sensor. Two independently adjustable on/off control point settings on the front panel meter cover the complete humidity range of the in strument. A latching function with indicating lights is provided for each control function. Phys-Chemical Re search 114 Portable ion counter Instrument measures the concentra tion of positive or negative small ions having a mobility of more than 0.76. Nine measuring ranges can be selected with full pointer deflection measuring concentrations between 500 and 5 Χ 106 ions/cm 3 . An output for a re corder is provided. International Controls 115
Specimen preparation system System provides the X-ray diffractionist with one source of tools and accessories to prepare specimens for camera and diffractometer work. In cluded are a selection of custom and specialty tools and materials for dif fraction work. The pyroceram work surface is heat, chemical, and abrasion resistant and is easily removed for cleaning. Buhrke Scientific 116 Air filter panels Available in 95-99.99% efficiencies, the filter media is nonflammable, bactericidal, and fungicidal paper folded into minipleats that provide unidirectional airflow. Filtra 117 Analytical cartridges Devices permit the automated analysis of ammonia, total phosphorus, total Kjeldahl nitrogen, silica, chloride, and several other parameters without changing cartridges. According to the manufacturer, the new cartridges provide analytical performance that is equivalent to single-test cartridges. Technicon Instruments 118 98A
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Air mass flow calibrator Portable unit can be used to calibrate personal air samplers, laboratory flows, process flows, and R & D . It has four mass flow ranges: 10-200 SCCM, 0-1000 S C C M , 0-5 FLPM, and 0-50 S L P M . Included with the instrument are a flow body, meter, 15-ft cable, battery charger, and carrying case. Sierra Instruments 125 Scanning spectrometer Instrument contains a direct-drive, 25 000 step/revolution stepper motor. Stepper-motor resolution, equivalent to 0.0002 nm/step, helps to ensure high-resolution spectra. To program and run the spectrometer, a minicom puter can be interfaced to the digital drive. The wavelength accuracy is better than ±0.2 μιη. Fisher Scientific 119
Electronic shear pin This can simplify the control of pumps, bar screens, gates, and scrapers where obstructions, overloads, and tramp materials are a problem. The pin monitors the motor load and can stop the motor or initiate a change. Ac cording to the manufacturer, the con trol point can be adjusted for precise control and the unit can also be used to detect loss of speed. MEKontrol 126
Variable wavelength detector Designed for use with high perfor mance liquid chromatography, this detector is continuously variable from 190-700 nm without lamp changes and has a high-pressure (1000 psi) fluid cell. The unit is linear through out its 11 sensitivity ranges of 0.001-2.0 A U F S . LDC/Milton Roy 120
Mercury vapor badge This device allows a known sample volume to enter through positive con trolled diffusion. The mercury is ab sorbed by a Hydrar sorbent and then may be analyzed by flameless atomic absorption using standard equipment. SKC 127
Temperature-controlled baths Available in sizes from 10-50 L, these units have digital controls. The stain less steel heater is controlled by a solid-state system, providing temper ature control to ±0.005 °C. The liquid circulation system includes a high speed stirrer. The overall temperature range is 0 °C to 80 ° C when the bath is used with a cooler unit. Science/ Electronics 121 Laboratory TOC analyzer Instrument measures low to high concentrations of purgeable, organic, inorganic, and total organic carbon. In the low range, the sensitivity is 100 ppb. An interactive operator prompt ing system minimizes human error related to sample size, ranges, and calibration procedures. The low-tem perature, UV oxidation system allows all reactions to take place in the liquid phase and shortens the analysis time required to 3-4 min/sample. Astro Resources 122 pH meters Pocket-size meters cover the 0-14 range and are equipped with sub mersible electrodes with sealed-in reference gel. Two models are avail able—one a direct-reading meter type, the other a digital type. Hellige 123
Stirring motor An LCD indicator on the motor shows rpm and permits reproducible stirring of samples. Continuously vari able-speed control accommodates two r a n g e s — 6 0 - 5 0 0 rpm and 240-2000 rpm. The chuck capacity is 0.5-10.0 mm. Tekmar 129 Rotary evaporator Variable speed control allows the evaporator to be used in a wide variety of applications that require precision control. According to the manufac turer, a unique release device helps to remove most stubborn flasks and pre vent the danger of breakage. Lab-Line Instruments 130
Temperature controllers Compact controllers occupy less than 2 X 2 in. of panel area and are housed in glass-filled nylon. Two styles are available. One style mounts in a relay socket and the other on a panel with screw terminal electrical connections. Gulton Industries 132
