Earlier this month, Sequoia sent out a survey to our LISST-ABS users to get feedback on how we can continue to improve this instrument. Survey participants were entered into a drawing for $200. Our winner was Cindy Crane from the Prince Edward Island (PEI) Department of Environment, Water and Climate...
In 2008, Sequoia Scientific’s Dr. Ole Mikkelsen co-authored and published a paper: The Influence of Schlieren on In-situ Optical Measurements Used for Particle Characterization. This paper was based on data collected during his postdoctoral work in Canada and the UK between 2002 and 2007. It was...
24th July 2020 In the last several years, Sequoia has introduced a range of new or upgraded instruments: LISST-200X, LISST-SL2, LISST-Holo2, LISST-ABS, LISST-AOBS, LISST-HAB, LISST-Black, LISST-Glider, Hyper-bb and LISST Horizon. Such an expansion increases inventory cost, documentation requirements,...
Sequoia’s LISST-200X has been designed to cover a wide range of particle concentrations. However, at high concentrations the light scattering from the particles can include multiple scattering. This will affect the measurement of particle size and concentration. The concentration where multiple...
January’s featured paper is here! Lepage H, Masson M, Delanghe D, Le Bescond C (2019): Grain Size Analyzers: Results of an Intercomparison Study. SN Applied Sciences (2019) 1:1100 | Tl;dr: No instrument in particular stood out as better or worse. But you probably shouldn’t compare...
As reports over the last 3-4 decades demonstrate increasing plastic concentration in the oceans, public and regulatory concerns have grown in parallel. Sequoia Scientific Inc. and other instrument manufactures are thus frequently contacted by scientists and regulators seeking tools that measure...
The short explanation Briefly, the difference between turbidity and Super-Turbidity (Patent Pending) can be summarized as follows: Turbidity (NTU) = Optical Backscatter; Needs Calibration for SSC; less accurate Super-Turbidity (mg/l) = Optical & Acoustic Backscatter; No Calibration for SSC; more...
LISST-AOBS has Nearly Uniform Sensitivity Across Wide Grain Sizes! B Why the Acousto-Optic Super-Turbidity Sensor LISST-AOBS? The sensitivity (Volts/[mg/L] ) of Optical turbidity sensors varies inversely with grain size. Turbidity sensors are highly sensitive to fine particles, and insensitive to large...
Welcome to the first installment of Sequoia’s Fun Fact Series! Irregularly, we’ll post interesting facts about sediments in this Fun Fact Series. To kick it off, we’ll go all the way back to the beginning – the very first known measurement of sediment anywhere in the world. Incredibly,...
LISST-SL2 Is Demonstrated in Yangtze River, Wuhan, China [This article shows an example of river data from a boat; for bridge-lowered data, click here.] The Yangtze River hydrological facility is located in Wuhan on the western bank. A map of the location can be found here (30°37’41.59″...