Sequoia Scientific, Inc. products

The LISST-200X marks a major advance in technology of our workhorse LISST-100X submersible laser-diffraction instruments used for use in rivers, streams, ports, harbors, coasts and oceans. It also measures the small-angle optical volume scattering function (VSF).

The LISST-HAB is a self-contained, stand-alone instrument system for use on profiling packages, towed and remote vehicle applications, for deployment during a HAB event. The system will continuously measure particle size distribution and concentration, along with the fluorescence of Phycocyanin (Freshwater HAB’s), Phycoerythrin (Marine HAB’s), Chlorophyll and beam attenuation.

LISST-Tau is a high-precision transmissometer for underwater vehicles, profiling packages, CTDs, and other systems. With high-quality optics and a carefully selected LED source, it transmits a collimated beam through the water, and precisely measures the light transmitted through its 15 cm path. Light modulation with synchronous detection rejects ambient light, while oversampling and averaging yield better than 16-bit resolution. LISST-Tau’s digital controller applies calibration coefficients, corrects for temperature effects, and transmits data from both digital and analog outputs. Included software provides real-time display of data, and functions for checking and updating pure-water calibrations. An optional flow-through chamber simplifies calibrations and experiments. LISST-Tau advances the state of the art for in-situ transmissometers.

Low-cost acoustic sensor directly measuring Suspended Sediment Concentration (SSC) at a point. Integrates easily with existing dataloggers or monitoring systems. Typical application areas: Environmental monitoring where SSC is of interest, hydropower, sediment studies. Sequoia is in discussion with potential parties that may take over production and are evaluating the technology and market. Sequoia will continue production until a decision has been made in this regard. Units are in stock for immediate delivery and Sequoia is still taking orders.

The LISST-Portable-XR is the world’s first and only battery powered portable particle size analyzer. It can be used in the field, in the laboratory or on the factory floor. The LISST-Portable|XR analyzes the sample in a wet state to obtain the particle size distribution and the particle volume concentration. The LISST-Portable|XR uses the same laser light scattering method (laser diffraction) as popular laboratory particle size analyzers.

The LISST-Holo2 frame (SEQ-AC-LHO2-FRM) will work for the LISST-100X (6/18/2024). See Gallery for drawings of the LISST-100X mounted in the LISST-Holo2 frame.

The LISST-Holo2 stores holograms for study of flocs, plankton, and other particles in water. It is an advanced successor of the original LISST-Holo. This new version is the world’s fastest, capturing holograms at 20Hz, [vs.0.2Hz for the original LISST-Holo]. New – the same original housing now includes an 8-hr battery and 250GB of memory. Another powerful new feature ranks thousands of your holograms based on richness of imagery – a Sequoia innovation, so you can see the most interesting ones first. The LISST-Holo2 will be available late July 2017. Contact us if you’d like to upgrade your original LISST-Holo.

The LISST-Deep instrument obtains in-situ measurements of particle size distribution, optical transmission, and the optical volume scattering function(VSF) at depths down to 3,000 meters. The LISST-Deep extends operating depth range beyond the LISST-100X or LISST-200X instruments allowing measurements of particle size to be made with at 1 hz with minimal disturbance to the particles.

AThe LISST-SL2 is Sequoia’s most powerful multi-parameter river sediment monitoring instrument. Delivers real-time Point-Integrated, Depth-Integrated, or time-series data. Replaces old technology samplers. The streamlined body is a minimum drag shape. In measures depth, velocity, temperature, concentration and size distribution of sediments and other auxiliary parameters. Based on laser diffraction. The system employs active control of an intake pump that matches intake velocity to river velocity (iso-kinetic). [The features section below lists new features.]

The LISST-StreamSide is developed specifically for monitoring applications, for example sediment monitoring in shallow streams and rivers or for storm runoff. It can also be used as an in-line instrument system, for example in a flow-through system on a research vessel. The first units shipped in May 2008.