Specific In situ Sensor Technologies

Gregory Bonito
Research Assistant
LTER Network / San Diego Supercomputer Center
gbonito@lternet.edu

Last update: October 3, 2003

The following describes some new and innovative sensor technologies applicable to ecological research and environmental monitoring. Many types of technologies are listed, with links to more detailed information. This is by no means a complete listing, as new and innovative technologies and instruments are continuously being developed through governmental and private sectors.

Table of Contents:

I. Vegetation Analysis
II. Soil Measurements
III. Telemetry - Organism Tagging
IV. Chemical & Biological Analysis of Gases, Liquids, Solids, & Atmosphere
V. Oceanographic Submersibles
VI. Oceanographic / Freshwater Platforms
VII. Oceanographic / Freshwater Sensors
VIII. Laboratories on a Chip
IX. Infrared Video
X. Weather Monitoring, Sensor Webs & Smart Dust
XI Compound Specific Stable Isotope Analysis
XII. High Performance Liquid Chromatography (HPLC)

I. Vegetation Analysis

Advanced Continuous Excitation Fluorometer - The determination of plant photochemical efficiency by chlorophyll fluorescence measurements provides fast and detailed complementary photosynthetic information, data which is particularly vital in plant stress physiology and related environmental investigations. For the accurate and rapid screening of plant photochemical efficiency, in the field or laboratory, ADC has introduced the Fim 1500- Fluorescence Induction Monitor. The Fim 1500 provides high frequency sampling of induced fluorescence and the automatic determination of Fo, Fm, Fv, Fv/Fm (Quantum Yield), Tmax and Area over Curve. http://www.adc.co.uk/products1.htm

Chlorophyll Fluorescence Measurements - The HEINZ WALZ GmbH offers a wide range of fluorometers for almost any application for plants. Aquatic and terrestrial models. http://www.walz.com/

Electronic Dendrometers - Highly precise electronic dendrometers measure the growth and size of plant stems and fruits. The effects of environmental factors on the water balance of plants and stem size variations over time are easily monitored with a temperature compensated dendrometer. Measurements are taken in real-time and are recorded on a data logger or computer, taking the signals from a full-bridge strain gauge sensor attached to a flexible arm of this calliper - style device. Non-destructive, Real-time measurements, Adaptable to computer systems, Long term measurements possible, Adapters for woody stemmed, herbaceous plants and fruits, Weatherproof and rugged for field studies. http://www.adc.co.uk/water.htm

High Pressure Flow Meter (H.P.F.M.) - The HPFM is one of the markets newest products. The instrument is designed to perform quantitative root and stem analysis without the need to excavate roots or transfer limbs back to the laboratory. In most cases, the analysis of a simple root or shoot is completed in as little as 10 minutes. You can quickly measure the hydraulic conductance in the soil-plant-atmosphere relationship. Root conductance in field or lab, Quick and simple to use, No need to excavate roots, User friendly software. http://www.adc.co.uk/water.htm

PAR (Photosynthetically Active Radiation) Sensor This instrument is model QSP-200PD, manufactured by Biospherical Instruments, Inc. It has a 1.9 cm (3/4") Teflon scalar collector and a spectral response of 400-700nm. http://www.biospherical.com/

Portable Photosynthesis Measurements - The LI-6400 Portable Photosynthesis System is setting the world standard for photosynthesis research with cutting edge technology. It solves the measurement problems of plant scientists by using new technology in a highly integrated system. It is the only really portable instrument, which combines all components (Computer, four Analysers, CO2-Control and Lightsource) in one single unit. http://env.licor.com/

Sap Flow Meters - Stem sap flow sensors have been designed for the accurate measurement of sap flow in plants and trees. These devices are used for field measurement of xylem sap flow rates in stems of large trees and work on the principle of heat balance of stem tissues. An advanced energy balance method, derived from a constant heat source, monitors sap flow in plants from 2mm to 125mm in diameter. Accurate, No calibration required, Non-intrusive, Simple to use, Portable, Scientifically proven. Many companies make these. http://www.adc.co.uk/water.htm

Visible Radiation Measurements - Quantum sensors for measuring photosynthetically active radiation (PAR), a highly accurate and low cost pyranometer for measuring total solar radiation, and a photometric sensor for lighting applications. Portable Spectroradiometer with a range of 300 to 1100 nm. Easy to use multi-channel datalogger for light sensors, temperature, rainfall and other types of sensors. http://www.glenspectra.com/

II. Soil Measurements

CHEMIN: Chemistry / Mineralogy Analyzer - Our small, portable CHEMIN instrument is a combined CHEMical and MINeralogic analyzer, the first instrument to perform both analyses simultaneously. CHEMIN records x-ray diffraction and x-ray fluorescence data from fine-grained or powder samples (less than a milligram) held in the path of an x-ray beam. Los Alamos, the NASA Ames Research Center, and the Jet Propulsion Laboratory have developed this instrument.
http://ees-www.lanl.gov/Capabilities/advsense/as_mars.shtml

Cone Penetrometer (CPT) - provides cost-effective, real-time data for use in the characterization of the subsurface. CPT can be adapted for new sensors to measure various types of chemical contaminants, soil vapor, ground water, pore pressure and other physical characteristics of the subsurface, as well as used to collect soil and water samples. Recent innovations in this baseline technology allow for improved access to the subsurface for environmental restoration applications. The technology has been improved by both industry and government agencies and is constantly advancing due to research efforts. http://www.liquefaction.com/insitutests/cpt/cpt-equipment.htm, http://vertek.ara.com/products/probes_index.html

Cone Penetrometer - Cone penetrometer technology (CPT) provides cost-effective, real-time data for use in the characterization of the subsurface. Recent innovations in this baseline technology allow for improved access to the subsurface for environmental restoration applications. Soil moisture, temperature, texture along with other parameters can be measured using CPT technology. http://www.em.doe.gov/plumesfa/intech/conepen/tech.html , http://www.gnet.org/archive/4569.html , http://www.cpeo.org/techtree/ttdescript/fiorhtdr.htm

Ground Penetrating Radar (GPR) - GPR has been used as a non-destructive method to study root systems, soil layers, sediment transport, ground water, and archeological sites, for instance. GPR works by using radar that transmits high frequency, short duration pulses of energy into the ground from a coupled antenna. Transient electromagnetic waves are reflected, refracted, and diffracted in the subsurface by changes in electrical conductivity and dielectric properties. Travel times of reflected, refracted and diffracted waves are analyzed to give depths, geometry and material type information. The energy returning to the antenna is processed within the control unit and displayed on graphic paper. http://members.aol.com/plysoil1/gpr.html, http://www.g-p-r.com/, http://www.sensoft.on.ca/

In Situ Non-Invasive Soil Carbon Measurement - The Carbon Sequestration Research Program called for development and demonstration of novel techniques for quantitative measurement of carbon changes in the soil. This project develops a robust, flexible, non-invasive, and practical method for monitoring and verifying temporal changes in soil carbon in situ. The method is based on Inelastic Neutron Scattering (INS) of fast neutrons from the carbon nucleus and detection of the subsequently emitted 4.4 MeV gamma rays. The two major objectives of this project are: (1) to construct a prototype of a field deployable Soil Carbon Measurement (SCM) system, and (2) to characterize, calibrate and test the SCM system in the Free-Air CO2 Enrichment (FACE) facility at the Duke Forest, NC. http://www.bnl.gov/des/ps_ebi.015.html

Infrared Point Spectrometer (IPS) - IPS reveals the mineralogy of rocks and soils from the near field to the horizon. Its wavelength range is sensitive to aqueously-deposited minerals such as clays and carbonates in addition to igneous minerals. http://fido.jpl.nasa.gov/technology.html

Minirhizotron - Manufactured by Bartz Technologies, minirhizotrons are essentially underground observatories that can be used to detect organisms, or monitor root growth and turnover. Minirhizotrons use a digital camera, which is lowered into a buried clear PVC observation tube. Features included on the camera: 100 x magnification, UV lighting, and soon automation. http://www.bartztechnology.com/products.htm

Tensiometers - Manual and Automatic ADC:SKYE tensiometers are precision made devices for measuring soil moisture pressure or water pressure. They measure directly in Hectopascals (or mbar) the suction pressure required to utilize the water in the measured area and hence the water available to the plant. http://www.adc.co.uk/soil.htm

Water Content Determination - The TRIME instruments offers a quick, reliable and simple way for water content determination with the Time Domain Reflectometry (TDR). Application fields are: industry, agriculture, soil science, geology, meteorology and other. http://www.dmp.ch/index.php?topgroupid=4 , http://www.atd.ucar.edu/rtf/facilities/isff/sensors/trime/FM-manual_e.pdf

III. Telemetry - Organism Tagging

Allflex Electronic Tag / Supertag - These tag systems are well developed and has been used in a wide range of applications. The tag is based on the Texas Instruments TIRIS technology. http://www.ti.com/tiris/

GPS Collars - State of the art GPS collars for wildlife allow for remote data download while the GPS collar is still on the animal, and data transmission directly from the GPS-GSM collar to your office/laptop via mobile phone system, or via two-way communication in the field. http://www.environmental-studies.de/

Digital Whale Tag - This site contains data from a digital tag for deployment on marine mammals, non-invasively attached using suction cups. The tag records acoustic data, including vocalizations and noise from nearby ships, and the simultaneous pitch, roll, heading, and depth of the tagged animal. Many marine mammals, in particular deep-diving animals, spend little of their time at the surface, where they can be observed. The tag records their behavior (including at depth), to complement focal observations at the surface. http://dtag.whoi.edu/tag.html

Radio Frequency Identification Tags (RFID Tags) - A Radio Frequency Identification Tag is part of a system designed to identify moveable objects and record data associated with them. A tag is fixed to the object to be identified and consists of a package (normally plastic) containing a passive electronic chip, which is connected to a compact antenna contained within the package. http://www.ti.com/tiris/default.htm

Telemetry - In its broadest sense, telemetry can be defined as the art and science of conveying information from one location to another. Spatial and environmental information can be transmitted from fish, reptiles, mammals, and avian through acoustic and radio telemetry. With acoustic telemetry, sound waves are utilized to convey that information. In situations where radio telemetry is not practical or appropriate (e.g., in deep or highly conductive water, i.e., salt water), researchers can use acoustic transmitters and receivers to track fish and wildlife. http://www.biotelem.org/manufact.htm

IV. Chemical & Biological Analysis of Gases, Liquids, Solids & Atmosphere

Bio-Contamination Sensor - (Food and Agricultural Products) - A new test for listeria and salmonella contamination in agricultural and food products does its work in less than 24 hours rather than the week required by conventional methods. Developed by the French firm Europrobe SA, the LUMIprobe 24 is based on solid-phase sandwich hybridization with luminescent detection. http://www.sensorsmag.com/isensors/dec01/searching/

Bioguardian Bioparticle Detector - InnovaTek, Inc. is commercializing a new generation of air samplers that use a combination of micromechanical and microfluidic technologies capable of trapping airborne viruses, bacteria, molds, and spores. Our Bioguardian™ technology can provide liquid sample with concentrated organisms to a number of different detection/identification technologies currently being developed. http://www.tekkie.com/mmac.htm

Carbon-Based Sensor - A wireless carbon dioxide (CO2) sensor is made by depositing a layer of multi-wall carbon nanotubes on the interdigital capacitor of a capacitor-inductor (LC) resonant circuit sensor The sensor tracks CO2 levels by monitoring the resonant frequency of the LC circuit, which shifts in response to changes in the complex permittivity of the carbon nanotubes due to CO2 absorption.

ChemLab on a Chip - The Department of Energy's Sandia National Laboratories has squeezed the mechanical "preconcentrator" device needed for its handheld chem-lab onto a single 2 mm2 chip. The preconcentrator chip will work with any handheld microanalytical system designed to sniff gases. The ChemLab chemical analyzer is small, uses minute amounts of power, and is inexpensive to produce. Watch a quicktime movie about this technology at the Sandia link. http://www.ca.sandia.gov/microchem/MicroChem1.html

Endospore Detection System - Ocean Optics has developed a low-cost. field-deployable endospore detection system that offers rapid front-end screening to instantly identify potential anthrax contamination. http://www.oceanoptics.com/products.asp

Fast Analysis of Microrganisms - the ImmunoFlow (Photo 3), incorporates a test chamber containing hundreds of glass beads, each coated with antibodies specific to the type of bacterium of interest. The reason ImmunoFlow is so much faster than conventional test methods is that there is no waiting time for bacteria to diffuse through a paper filter impregnated with antibodies. Sensitivity is another improvement-detection limits are <10 cells or spores for each organism. http://www.foodtech.usu.edu/

Handheld Chemical Sensor - The VOCcheck handheld sensor system allows for on-site analysis of volatile compounds. The VOCcheck sensor weighs under 1 pound and offers rapid response within 10 seconds. Information can be transferred from one device to another or to a PC. A rechargeable battery provides 70 hours of standby time and up to 1,000 measurement cycles. It operates using four Quartz Micro Balance (QMB) sensors.
Company web site at http://www.appliedsensor.com.

Hand Held Gas Chromatograph - The EVM II was developed under Contract DAAA15-94-C-0001 as a Small Business Innovative Research Contract in association with the U.S. Army, Edgewood Research Development Engineering Center (ERDEC). It is based on the proven Ion Mobility Spectrometry (IMS) technology for ultra sensitive detection of gas phase analytes with high speed Automated Vapor Sampling (AVS) - Transfer Line Gas Chromatography (TLGC)sampling and separation capabilities developed by FemtoScan and the University of Utah. The EVM II is a sensitive and selective, near real-time vapor detector. The combination of intelligent AVS injections, rapid TLGC separations and high sensitivity IMS detection leads to the first hand-portable hyphenated analytical instrument. The result is an instrument with unparalleled analytical capability in a hand- portable package that is ready for your most demanding on-line, real-time measurement problems. http://www.femtoscan.com/evm.htm ,http://www.hapsite.com

The Electronic Nose - The electronic nose (e-nose) is a new ultrasonic gas and particulate matter sensor that is portable, accurate, and affordable for applications in almost every industry and work environment. The sensor is the first handheld instrument of its kind to accurately detect and quantify levels of trace gases and particulate matter in air with real-time monitoring. The sensor uses an ultrasound pulse to measure the concentration of trace gases or particulate matter. For additional information, http://www.techtransfer.anl.gov/highlights/11-2/gassensor.html, http://enose.jpl.nasa.gov/Tech_pubs.htm

Electronic Nose - An electronic nose is composed of an array of chemical sensing devices and an automated pattern recognition system. The array of chemical sensors swell and shrink, depending on what trace vapors may be present in the air. This variation is measured, and certain elements in the air identified. The electronic nose is a powerful instrument for odor analysis. The sensing system can be an array of chemical sensors where each sensor measures a different property of the sensed chemical, or it can be a single sensing device (e.g., gas chromatograph, spectrometer) that produces an array of measurements for each chemical, or it can be a hybrid of both. Each odorant or volatile compound presented to the sensor array produces a signature or characteristic pattern of the odorant. With many environmental applications, systems are compact, portable, and capable of quickly identifying contaminants in the field. http://www.emsl.pnl.gov:2080/proj/neuron/papers/keller.isic99.html, http://www.emsl.pnl.gov:2080/proj/neuron/papers/keller.spie99a.html

New Electronic Nose - The gas chromatography/surface acoustic wave (GC/SAW) electronic nose system is based on fast gas chromatography. Gas chromatography encompasses various techniques, all of which entail separating the components of a mixture by preferential adsorption in an ascending molecular-weight sequence onto a solid adsorbent material applied as a coating to the interior of the chromatography column. Each gas is identified by its unique retention time, or the time at which the center of a symmetrical peak appears on the chromatogram. For the first time, researchers and quality-control engineers are able to measure the chemistry of vapors in near real time. We are surrounded by hydrocarbons that our noses sense as "smells." The ability to identify and quantify them has an almost infinite number of applications. http://www.sensorsmag.com/articles/0599/0599_p33/index.htm, http://www.businessweek.com/bwdaily/dnflash/dec2000/nf20001218_725.htm

Electronic Tongue - The E-tongue is a new generation analytical instrument based on an array of non-selective chemical sensors (electrodes) and pattern recognition and/or multivariate analysis methods for the data processing. Chemical sensors incorporated into the array exhibit high cross-sensitivity to different components of analyzed liquids, both inorganic and organic, ionic and non-ionic. The electronic tongue uses a combination of state-of-the-art micromachining, novel photochemical sensing schemes, molecular engineering of receptor sites, and pattern recognition protocols to detect a variety of important biological and chemical agents. This exquisitely powerful sensor array allows for the simultaneous detection and quantification of multi-analyte systems, while also properly "rejecting" irrelevant chemical/biochemical species in the environment. The sensor array structures are compatible with microfabrication methods leading to small and inexpensive (i.e. disposable) sensor units. http://www.eng.warwick.ac.uk/SRL/e-tongue.htm ,http://www.nature.com/nsu/020107/020107-3.html, http://www.wired.com/news/technology/0,1282,16016,00.html , http://www.sciencedaily.com/releases/2002/05/020513075143.htm

Fast Infrared Gas Analyser - The world standard for environmental carbon dioxide and water vapour gas measurements. http://www.glenspectra.com/glen/licor/licor.htm

Miniature Mass Spectrometer - A miniature spectrometer unit weighting about 5 pounds and roughly the size and shape of a small shoe box has been developed by the Jet Propulsion Laboratory. A small screen displays a graph that reports the detection of specific gases and their amounts. JPL technologists are working to improve the miniature mass spectrometer by creating new custom electronics to reduce its power consumption. http://www.jpl.nasa.gov/technology/images_videos/iv_pages/D2000_1026_B2.html

Miniature Fiber Optic Spectrometer - Starting at just $2,199, is a small-footprint (about the size of a deck of cards), plug-and-play version of Ocean Optics' revolutionary S2000 Miniature Fiber Optic Spectrometer. http://www.oceanoptics.org/products/spectrometers.asp

Portable Apparatus for Rapid Acquisitions of Bidirectional Observations of Land and Atmosphere (PARABOLA III) - (Remote Method) - PARABOLA III, now commercially available, is designed to measure the reflected signature of a variety of Earth surface types, from rangeland vegetation to ice and snow. It can rapidly acquire data for almost the complete sky and ground-looking hemispheres, with no missing data or "dead cone" and sufficient dynamic range to measure direct solar radiance. PARABOLA III was actively used in the Boreal Ecosystem-Atmosphere Study (BOREAS). http://www.sti.nasa.gov/tto/spinoff1997/er8.html

Raman imaging microscope (PRIM) - A new, portable instrument developed by Purdue University chemists will allow researchers to analyze the chemical content of a wide variety of materials in the field - whether it's a laboratory, classroom, doctor's office or farm field. The instrument, called a portable Raman imaging microscope, or PRIM, is designed for advanced materials diagnostics. It uses laser light to "read" the distribution of chemicals present in a sample in real time, providing a detailed chemical analysis in seconds. PRIM was developed in collaboration with SpectraCode Inc. http://news.uns.purdue.edu/UNS/html4ever/010720.BenAmotz.PRIM.html

Rapid Trace Gas Detection - Scientists at the University of Maine's Laboratory for Surface Science and Technology are working on microscopically manufactured surfaces that respond in predictable ways when exposed to certain gas molecules. These microchip-size sensors can detect extremely minute traces of gas within minutes, or even within seconds of exposure. http://www.ume.maine.edu/LASST/

Soil and Groundwater Chemical Sniffer - Sandia researchers Cliff Ho and Bob Hughes are working on a real-time, on-site gas- and water-quality monitoring sensor system. The device is based on a chemiresistor, an array of miniature, polymer-based sensors, each of which responds to a particular VOC (volatile organic compound). One particularly neat feature of the new sensor is that it can handle chemicals in both gas and aqueous phases-under water or in the soil. http://www.sandia.gov/media/NewsRel/NR2001/watsniff.htm

Stage Air Particle Analyzer - A Multiple Crystal Oscillator is used to measure air pollution. This technology, which was used as real time particle mass sensors in the company's PC-2H 10 Stage Air Particle Analyzer, can determine the size and quantity of aerosols in the atmosphere at a particular time. http://www.californiameasurements.com/html/product.html , http://techtransfer.jpl.nasa.gov/successstories/environ_protection/measuring-air-pollutants.html

Tunable Diode Laser Chip - Tunable diode lasers (TDL) are used in gas sensors. The heart of a TDL system is a small laser diode (about 2mm2) that produces a very narrow and specific wavelength of light tuned to a harmonic frequency of the water vapor molecule in the near infrared band. The light causes the molecule to vibrate and therefore absorb energy. Once adjusted to the specific frequency of the molecule, the laser is minutely tuned to different wavelengths on either side of the target wavelength. By comparing the light energy being absorbed at the water vapor frequency to the light energy at the surrounding frequencies, a very precise measurement can be made. http://www.i-leos.org/info/tunable_diode_lasers.asp, http://aemc.jpl.nasa.gov/activities/act_index.html

Ultra-level SO2 and NO2 Analyzers - Environmental monitoring specialist, Enviro Technology Services introducing two new analysis that will provide accurate and dependable ultra low-level measurements of SO2 and NO2. The proven fluorescent principle coupled with state-of-the-art, microprocessor technology provides a versatile SO2 instrument with full scale, user selectable ranges between 0-50ppb to 0-20ppm. Utilising chemiluminescent technology, the API model 200AU measures NO/NO2/NOx and offers sensitivity ranges of 0.5 ppb to 0-2000 ppb with a lower detection limit of 50 ppt (part per trillion). http://www.chemsoc.org/chembytes/products/products.htm

V. Oceanographic Submersibles

ABE (Autonomous Benthic Explorer) - ABE is an underwater robot designed to do deep ocean surveys. It is powered by lead-acid batteries, can operate as deep as 5500 meters, and can travel a bit over 10 km at a speed of 65 cm per second. It carries two black and white video cameras, temperature and salinity sensors, an optical backscatter sensor to tell if there's anything making the water murky, a magnetometer to measure near bottom magnetic fields, and an acoustic altimeter to keep it from running into things. http://www.dsl.whoi.edu/DSL/dana/abe_cutesy.html

NOAA Submersibles - Over the last few decades, engineers have developed submersible technologies (found here) capable of meeting the many challenges that the deep sea imposes upon explorers. Using advanced submersible technologies, remarkable new deep-water ecosystems have been discovered. http://oceanexplorer.noaa.gov/technology/subs/subs.html

NOAA Vessels - These ships (described below) provide stable platforms from which explorers can deploy equipment, divers, and submersibles. In addition, they carry state-of- the-art electronics, computers, and navigational and communications systems to analyze the data they gather, and provide the crew with up-to-the-minute information about the ever-changing ocean environments. http://oceanexplorer.noaa.gov/technology/vessels/vessels.html

NOAA - Diving - In this section, diving, we highlight some of the technical advances in diving and discuss some of the problems we still must overcome. http://oceanexplorer.noaa.gov/technology/diving/diving.html

Remote Environmental Monitoring UnitS (REMUS) - is a small, lowcost autonomous underwater vehicle designed for environmental monitoring. It was developed by engineers in the Oceanographic Systems Laboratory of the Woods Hole Oceanographic Institution. The REMUS vehicle is an integral part of the LEO-15 design. It will be used to exploit the real time deployed presence that the seafloor observatory offers by making measurements of episodic events which take place in locations which are remote from the cable. http://www.whoi.edu/home/marine/remus_main.html

Undersea Vehicles - Undersea vehicles are used to study ocean systems, deep sea vents, and to navigate and gather information from other extreme environments. Vehicles are rather expensive and are usually 1 of a kind developments. Information on sensors used on these vehicles can be found at: http://www.nurc.uconn.edu/ , http://www.qinetiq.com/services/sensing/services.html

VI. Oceanographic / Freshwater Platforms

Aerosol & Rainwater Samplers and Sensors for Ocean Buoys - This section will describe progress being made on projects for an elemental aerosol sensor and Fe rainwater sensor that attach to ocean buoys. http://www.whoi.edu/science/MCG/people/esholkovitz/sea_aer/buoy_rain_solas.html

Benthic Acoustic Stress Sensor (BASS) - This large tripod is actually just a skeleton to support many instruments including the Benthic Acoustic Stress Sensor. The tripods can actually vary in height from 10 to 20 feet or so. The BASS sensor measures current velocities and directions in the bottom 10 feet of the water column. When the tripod is deployed, there are usually many instruments from different universities measuring anything from temperature to taking images of the ocean bottom. http://marine.rutgers.edu/mrs/LEO/bass.html

BIOMAPER II (BIo- Optical Multifrequency Acoustical and Physical Environmental Recorder) - four major electronic systems and sensors on the towed vehicle (Acoustics, VPR, Environmental Sensing System, and Bio_Optical sensing system) are used to make physical, chemical and biological oceanographic assessments. http://globec.whoi.edu/images/gb/bmapcombo.html, http://www.htisonar.com/pub1.htm

CTD (conductivity, temperature, depth) - The device's primary function is to detect how the conductivity and temperature of the water column changes relative to depth. The CTD is torpedo-shaped and may be deployed by itself, attached to a submersible, or as part of a larger metal water sampling array known as a rosette, or carousel. Multiple water sampling bottles are often attached to the rosette to collect water at different depths of the cast. Further information is available from SeabirdElectronics. http://oceanexplorer.noaa.gov/technology/tools/sonde_ctd/sondectd.html

Drifters -are devices used by scientists to help grasp the complexities of global ocean currents, and, in turn, the many systems that they influence. With advances in technology, drifters now provide researchers with information about ocean circulation patterns in real time. http://oceanexplorer.noaa.gov/technology/tools/drifters/drifters.html

Freshwater Moored Profiler - Trout Lake Research Station added the unique remote sensing buoy this summer to its arsenal of water research tools. The $85,000 monitoring buoy is putting out a steady stream of data on the water and the atmosphere. In turn, the data is feeding the station's long-term research efforts. Among the sophisticated gadgets on the buoy is a "vertical profiler," a unit that can probe the deepest point in Trout Lake - 107 feet - and provide all sorts of water quality measures along the way. The profiler is attached to a cable and controls its buoyancy like a submarine and measures water temperature, clarity, mineral content, dissolved gases, pH and chlorophyll levels. From above, it tracks wind, barometric pressure, relative humidity, light and air temperature. Collectively, the information is the raw material for the station's Long-Term Ecological Research project, which is helping track global warming, pollution and landscape changes that take ages to manifest themselves. http://www.cnn.com/2000/NATURE/08/14/deep.buoy.enn/

Marine Moored Profiler - A newly developed instrument, the Moored Profiler, shows promise for enhancing the temporal sampling at conventional ship-supported ocean time-series stations and expanding the network of such stations beyond the current handful of sites. The Moored Profiler is an autonomous device, capable of propelling itself repeatedly along a conventional subsurface mooring line carrying oceanographic sensors through the water column. The device is operational to full-ocean-depth (profile range limited only by the length of mooring wire employed) and has a range of one-million-meters of vertical travel (200 profiles over a 5000-m depth interval, or any variation thereof). Thus far, the vehicle has been fitted with a CTD for measuring temperature and salinity as a function of depth, and an acoustic travel-time current meter for observing ocean currents. Future addition of biochemical and optical sensors is envisioned. http://www.bbsr.edu/Labs/hanselllab/s2o2/mp.html , http://www.whoi.edu/PO/

MITESS (Moored In-situ Trace Element Serial Sampler) - Developed to allow for high-frequency upper-ocean time-series sampling for trace metals. This data effort is directed at understanding the variability of trace metals with respect to fluxes from the atmosphere, physical processes (mixed layer and seasonal thermocline development, and vertical mixing), and biogeochemical activity. http://boyle.mit.edu/~ed/MITESS/MITESShomepage.html , http://www.opl.ucsb.edu/tommy/pubs/hawaii01/boyle.pdf

Moored Oceanographic Spectroradiometer - Moored spectroradiometers used to assess the primary productivity of the ocean were developed by Biospherical Instruments with the support of the JPL/NASA SBIR Program. This instrument provides unattended monitoring of natural fluorescence and environmental conditions for a period of several months at a moored location. The instrument greatly enhances the value of satellite observations of surface conditions, providing direct measurements of phytoplankton and ocean conditions. http://sbir.gsfc.nasa.gov/SBIR/successes/chemis.htm

Oceanic Remote Chemical-optical Analyzer (ORCA) - The goal of this project is to develop and maintain a profiling mooring with a variety of chemical and optical sensors to monitor water quality in South Puget Sound - an area potentially at risk to impacts from eutrophication. http://www.ocean.washington.edu/research/orca/

Rotary Sidescan (sector scanning) sonar - The sector scanning sonar images an seafloor area of approximately 35m2 by projecting a beam of sound 0.8° wide in azimuth by 30° high in elevation on a center axis aimed 60° above vertical as shown in above. This system was originally designed by Simrad/Mesotech for use in imaging the insides of pipes and was adapted for coastal seafloor imaging applications with a cable to shore by Hay [1994]. At WHOI it was modified for autonomous use on the continental shelf by adding a PC 104 controller and hard disk data storage system. http://www.onr.navy.mil/sci_tech/ocean/reports/docs/mg/01/mgtrayk2.pdf

Sea Sled - The sea sled is an instrument system for taking high resolution measurements of beach profiles and ripple geometry. The sled is towed out from the shore by a boat to beyond the surf zone. It then moves in and out across the surf zone by using a truck-mounted winch on the landward side and either an anchored pulley or a boat on the seaward side. The sled's position and level are exactly surveyed from shore by a survey instrument sighting onto a prism mounted on top of the mast. An inclinometer corrects for the tilt of the sled. Ripples are measured using a wheel that moves up and down over the ripples as the sled is dragged back and forth. Ripples are also monitored using an oblique (sideways-looking) underwater video camera. http://www.niwa.co.nz/rc/prog/chaz/news/erosion

Side-scan Sonar - A side-scan sonar is an acoustic instrument for mapping the various types of substrate on the sea floor. A torpedo-like transducer, towed behind a vessel, sends out multiple sound beams 50-150 m on either side of the vessel. These beams are scattered off bottom features, and received again a few seconds (or fractions of seconds) later by the sonar. This time will be short when the features are close to the boat and longer when they are farther away. The resulting image is like an aerial photograph of the sea bed. http://www.abc.se/~pa/mar/sidescan.htm

Sondes - are ideal for profiling and monitoring water conditions in industrial and wastewater effluents, lakes, rivers, wetlands, estuaries, coastal waters, and the open ocean. Torpedo-shaped in appearance, sondes may have multiple sensors that record a range of water quality data. If the sonde has "on board" battery power, it can be left unattended for weeks at a time, with measurement parameters sampled at preprogramed intervals and data securely saved in the unit's internal memory. http://oceanexplorer.noaa.gov/technology/tools/sonde_ctd/sondectd.html

Video Plankton Recorder (VPR) - The VPR is an underwater video microscope system for rapid automatic quantification of plankton taxonomic composition, size structure, and abundance. The VPR is used for imaging plankton and other particulate matter in the size range from a few micrometers to several centimeters. It consists of four video cameras (with magnifying optics) synchronized at 60 fields per second (fps) to a red-filtered 80 W xenon strobe (pulse duration = 1 microsecond). Video data are telemetered to the surface via fiber optic cable and stored, together with time code overlay, using broadcast quality video tape recorders. Abundance is calculated from the video by counting number per field and dividing by the field volume. Pattern recognition algorithms are being developed for automated analysis of the VPR images. http://zooplankton.lsu.edu/vpr.htm

VII. Oceanographic / Freshwater Sensors

Acoustic Doppler Current Profiler - An acoustic doppler current profiler (ADCP) is an instrument for measuring vertical current profiles. It hangs over the side of the vessel. It emits an acoustic beam, which then scatters off particles at different vertical locations in the water column and is received a few fractions of a second later. Current speed is measured by difference between the time the acoustic beam should take to return to the receiver and the actual time. Sound waves will travel at different speeds depending on whether they are travelling with the water currents or against (the Doppler effect). http://www.rdinstruments.com/ , http://www.sontek.com/ , http://www.nortekusa.com/

Biochemical Oxygen Demand (BOD) Sensor - The biochemical oxygen demand (BOD) is one of the most widely used and important tests in the measurement of organic pollution. The conventional BOD test requires a 5 day incubation period and values of the test results depend upon the skill of the operator. Therefore, rapid and reproducable methods are desirable for the BOD test. The sensor utilizes a yeast called Trichopsporon cutaneum for waste water treatment. A continuos flow system using a new microbial sensor was developed for automatic estimation of 5 day BOD tests. Furthermore, the BOD of various types of untreated industrial waste water can be estimated by the sensor. http://www.velp.it/NewFiles/en_sensor.html , http://staff.aist.go.jp/zhen.yang/Publications/micro_oxygen_sensor.htm

Biomonitoring and Chlorophyll-Analysis - The density of algae or respectively the density of chlorophyll can be determined accurately by the bbe-Flourometers. These instruments measure the concentration of algae in water and furthermore analyse parameters such as algae activity. Extreme attention is payed to the parallel detection of different algae classes. http://axpfct.ct.infn.it/~archeo/LinkRaman.htm

Dissolved Oxygen Sensors - A variety of probes and instruments are available for the measurement of dissolved oxygen. http://www.appliedmicrosystems.com/sensors/dissolved-oxygen.htm , http://www.ysi.com/environmental-monitoring/dissolved-oxygen-sensors-ysi.htm , http://www.campbellsci.com/dissoxy.html

Environmental Sample Processor- The phytoplankton ecology group at MBARI is developing a new class of instrumentation that not only allows for the autonomous collection archival of phytoplankton samples but also enables real-time detection of specific microorganisms in situ through application of molecular probes. One of the major instruments currently being developed is the Environmental Sample Processor (ESP). http://www.mbari.org/microbial/esp.htm

Fast Lake Profiler - Instrument for lake profile measurements of dissolved oxygen, pH, conductivity, turbidity, temperature and pressure up to 400 m water depth. http://www2.cwr.uwa.edu.au/~fieldops/instrumentation/micro.html

Fast Repetition Rate Fluorometer - The instrument is used to measure the fluorescence of phytoplankton, providing information on ocean activity and productivity. It is non-destructive and can be used in situ. http://techtransfer.jpl.nasa.gov/successstories/environ_protection/ocean-research.html

Flourometer - Fluorometers measure Chlorophyll-A concentrations in the range of 0.03 ug/l to 30ug/l. It works my measuring the small amount of fluorescence generated by Chlorophyll A when excited by a 455nm (blue) LED source. http://www.wetlabs.com/

Laser Raman Spectrometer - In this new project we seek to extend MBARI's deep-sea measurement capability by adding Raman spectroscopy to the suite of tools available for both laboratory and in situ work. This is a powerful, nondestructive, tool for obtaining quantitative vibrational data on a wide variety of solutions, and solids, and under extreme conditions. http://www.mbari.org/rd/projects/2000/instruments/acquisition.html

Metal Pollutant Sensor - Researchers Brigham Young University have developed a system that enable a sensor to continually measure metals levels in water as it flows. The system works by adapting a method of monitoring the levels of metals released into the environment by mining, smelting, fossil fuel combustion, and industrial use. The metals include zinc, mercury and cadmium.

Modular Acoustic Velocity Sensor (MAVS) - a true three dimensional, high performance acoustic current meter which employs a differential travel time measurement technique. The current meter takes measurements across 4 acoustic axes to provide a true vector averaged velocity measurement. Programmable burst mode and triggered sampling provide the most flexible current meter available. http://www.nobska.net/mavs.htm

Optical and Automated Nutrient Analyzers - The MBARI chemical sensor program continues the development of in situ, ultraviolet spectrophotometric (ISUS) sensors. In addition, we will continue the development of solenoid-pumped, submersible chemical analyzers for in situ trace element measurements and for phosphate and silicate analyses. We believe that the simplicity of direct chemical sensing with ISUS sensors will make this approach the method of choice for measurements of chemicals that absorb light in the UV region (NO3-, NO2-, HS-, DOC). http://www.mbari.org/rd/projects/2000/instruments/mbari_chemical.html

Optical Backscatter Sensor - The concentration of suspended solids in the water column is determined using a submersible Optical Backscatter Sensor (OBS). The OBS operates by sending a beam of infrared light into the water , the beam is scattered by suspended particles and the OBS then measures the quantity of light that is reflected back to its sensor. The instrument is calibrated each sampling date by comparing the OBS values to collected water samples.
This instrument is manufactured by D&A instrument company, Port Townsend, Washington. http://www.seabird.com/application_notes/AN16.htm

Precision pressure sensor - This instrument, is bottom moored, it does not move with the profiler. It is a model 8WD020-1 manufactured by Paroscientific, Inc.

Semipermeable membrane devices (SPMDs) - are a passive sampling device used to monitor trace levels of organic contaminants. When placed in an aquatic environment, SPMDs accumulate hydrophobic (water-"hating", fat-"loving") organic compounds, such as polychlorinated biphenyls (PCBs), polyaromatic hydrocarbons (PAHs), and organochlorine pesticides from the surrounding waters. http://oceanexplorer.noaa.gov/technology/tools/spmds/spmds.html

Solid State Nutrient Analyzers - This project uses recent advances in Micro Electro-Mechanical Systems (MEMS) to develop miniature general purpose fluid handling systems and chemical analyzers on a silicon/PVC/glass wafers that can be used at any depth within the ocean. http://www.mbari.org/rd/projects/2000/instruments/solid.html

Temperature Microstructure Profiler - This high speed high resolution temperature profiler is used for the measurement of temperature microstructures in lakes to study effects of turbulent mixing in natural stratified water bodies. http://opd.apl.washington.edu/tools/

Transmissometer - This instrument is manufactured by Seatech, Inc. of Corvallis, Oregon. It uses a 10 cm path length and a 660nm LED as a light source. http://www.iopan.gda.pl/~sagan/bdo/ap_c660.htm

Underwater Radiation - LI-COR provides two types of sensors for underwater radiation measurements (cosine corrected and spherical). http://www.eurosep.com/Dep_biolog/bvdat62.htm

VIII. Laboratories on a Chip

Biochips - Biochips first came on the commercial radar screen in the early 1990s with the publication of early work on DNA microarrays from the group, led by Stephen Fodor, that was later to become the industry leader¾Affymetrix, Inc. (Santa Clara, CA). Meanwhile, a second branch of biochip technology was developing under the auspices of individuals such as Andreas Manz, originally at Novartis (Basel, Switzerland), Jed Harrison, now at the University of Alberta (British Columbia, Canada), and J. Michael Ramsey of the Oak Ridge National Laboratories (Oak Ridge, TN). These pioneers in the biochip field developed the microfluidics-based "lab-on-a-chip" concept. Today, these two branches¾microarrays and microfluidics¾ form the dichotomous biochip industry. Argonne's advanced biochip can perform thousands of biological reactions, such as decoding genes, in a few seconds. Biochip applications include finding differences between individual human immune systems, monitoring the environment and discriminating between deadly and closely related but harmless bacteria.
http://www.chemsoc.org/networks/locn/index.htm
http://www.techtransfer.anl.gov/partners/motorola-packard.html, http://www.spie.org/web/oer/march/mar00/biochips.html

Biochips / Gene Chips- The term "biochip" has taken on a variety of meanings. In the most generic sense, any device or component incorporating biological (or organic) materials -- either extracted from biological species or synthesized in a laboratory -- on a solid substrate can be regarded as a biochip. In practical terms, however, biochips often involve both miniaturization, usually in micro-array format, and the possibility of low-cost mass production. Biochip applications include finding differences between individual human immune systems, monitoring the environment and discriminating between deadly and closely related but harmless bacteria. This technology promises to monitor the whole genome on a single chip so that researchers can have a better picture of the interactions among thousands of genes simultaneously. Instead of reading DNA one letter or word at a time, biochips read whole phrases and sentences at a time. For a comprehensive resource base see: http://www.gene-chips.com/ , http://www.spie.org/web/oer/march/mar00/biochips.html

Camera on a Chip - The requirement for low-cost, compact imaging systems used in spacecraft has made cameras the size of a computer microchip possible. Applications of this state-of-the-art technology include personal computer video conferencing, digital still cameras, medical instruments, toys, and various automotive applications. The complementary metal-oxide semiconductor Active Pixel Sensor (CMOS-APS) technology enables the integration of a complete imaging system, including pixel array and control area, onto a single piece of silicon. One benefit is that it greatly reduces power consumption and lowers the number of parts needed in finished imaging products. http://www.sti.nasa.gov/tto/spinoff1999/ch2.htm, http://www.bell-labs.com/news/1998/july/15/1.html

Camera-on-a-Chip - Photobit Corporation of Pasadena, California, first received exclusive license to a new type of image sensor developed at the Jet Propulsion Laboratory (JPL). CMOS-APS technology enables the integration of a complete imaging system, including pixel array and control area, onto a single piece of silicon. One benefit is that it greatly reduces power consumption and lowers the number of parts needed in finished imaging products. Further--more, by combining all camera functionsfrom the capture of photons to the output of digital bits--CMOS sensors offer enhanced reliability, facilitate miniaturization, and allow on-chip programming of frame size, exposure, and other parameters. http://www.sti.nasa.gov/tto/spinoff1999/ch2.htm, http://www.jpl.nasa.gov/technology/images_videos/iv_pages/camera_on_a_chip.html
http://www.salon.com/tech/view/2000/05/22/kemeny/

ChemLab on a Chip - The Department of Energy's Sandia National Laboratories has squeezed the mechanical "preconcentrator" device needed for its handheld chem-lab onto a single 2 mm2 chip. The ChemLab on a chip is a microanalytical system designed to sniff gases. It is small, uses minute amounts of power, and is inexpensive to produce. http://www.eetimes.com/story/OEG20000912S0060, http://www.eet.com/story/OEG19991102S0044 , http://www.ca.sandia.gov/microchem/MicroChem1.html

Laboratory-on-a-Chip (DNA, RNA, Protein anlysis) - The Lab-on-a-Chip technology (developed by Agilent's partner, Caliper Technologies Corp.) is based on microfluidics, a technique that allows samples of fluids to be prepared and analyzed within the confines of a microchip. The chip itself consists of a network of tiny channels manufactured in glass that serve as pathways for the movement of fluid samples. Fluids move as voltage gradients are created across the fluid, simulating the action of much larger valves and pumps. When the chip is loaded with samples and placed in the Agilent 2100 bioanalyzer, electrodes attached to the lid of the analyzer sit down into fluid wells on the chip, and testing begins. LabChips® are available to analyze protein, DNA, and RNA in fluid samples. The analysis of the sample takes place as fluids are moving through the chip in a process called electrophoresis. http://www.labonachip.org.uk/aboutmini.shtml, http://www.labs.agilent.com/news/2000features/fea_hancock.html

Additional MEMS Resource - http://www.smalltimes.com/

IX. Infrared Video

Quantum Well IR Camera - This camera uses highly sensitive arrays in infrared photodetectors known as quantum well infrared photo detectors (QWIPS). The camera features a large-area, long wavelength QWIP focal plane array, which gives it greater sensitivity, resolution and stability than previous infrared cameras. The array can detect infrared radiation in the 8-to 9-micrometer (millionths of a meter) wavelength range. These wavelengths are 20 times longer, or lower in energy, than visible light. At these wavelengths, objects at room temperature glow the same way red-hot objects glow when viewed by the naked eye. http://qwip2000.jpl.nasa.gov/ , http://www.spie.org/app/education/index.cfm?fuseaction=videodetail&product_id=68

Uncooled IR Cameras - Using a design concept from a BMDO SBIR contract, Sensor Unlimited (Princeton, NJ) has developed an uncooled version of a near-infrared (IR) camera that is less expensive and cumbersome than its cryocooled counterparts. Sensors Unlimited has sold several of the commercially available cameras for uses such as surveillance and manufacturing process control. http://www.acq.osd.mil/bmdo/bmdolink/html/sensors.htm

X. Weather Monitoring, Sensor Webs & Smart Dust

Dew Point Sensor - The dew point sensor presents innovative and excellent technical solutions where the humidity of air or other gas is an important parameter and has to be known with high accuracy. Important uses with a wide range of applications. http://www.dmp.ch/instr/dewpoint/dewpoint.htm
Micro-weather Stations - the Jet Propulsion Laboratory is developing a series of micro-weather stations which include: microhygrometer for humidity measurement, micro-pressure, micro-temperature sensors, and micro laser Doppler anemometer for measuring wind. These devices are accurate, sensitive, low mass:volume, and low power requirement systems. For more information contact JPL. http://www.sensorsmag.com/articles/0802/RH/main.shtml , http://www.jpl.nasa.gov/news/fact_sheets/csmt.pdf

Sensor Webs - The Sensor Web is an independent network of wireless, intra-communicating sensor pods, deployed to monitor and explore a limitless range of environments. This adaptable instrument can be tailored to whatever conditions it is sent to observe. Sensor pods can be scattered over land or water areas or other regions of interest to gather data on spatial and temporal patterns of relatively slowly changing physical, chemical, or biological phenomena in those regions. http://sensorwebs.jpl.nasa.gov/ http://sensorwebs.jpl.nasa.gov/resources/sensorweb-concept.pdf, http://sensorwebs.jpl.nasa.gov/resources/Delin-Jackson2000.pdf

Smart Dust - The science/engineering goal of the Smart Dust project is to demonstrate that a complete sensor/communication system can be integrated into a cubic millimeter package. This involves both evolutionary and revolutionary advances in miniaturization, integration, and energy management. We aren't targeting any particular sensor, in fact there is no direct funding for sensor research in the project. We're funded by DARPA, so we will demonstrate Smart Dust with one or more applications of military relevance. In addition, we're pursuing several different applications with commercial importance, and we've got a long list of applications to work on if we only had the time. http://robotics.eecs.berkeley.edu/~pister/SmartDust/

Smart Pebbles - Crossbow and UC Berkeley's Computer Science Department are commercializing microsensor motes, a sort of "smart pebbles" first developed at Berkeley with funding from the Defense Advanced Research Project Agency (DARPA). The MICA product line includes sensor and processor boards and wireless communication processor modules that enable rapid development of wireless sensor networks. At present, MICA units can detect ultra-small vibrations, acoustic noise, magnetic disturbances, light, temperature, and proximity. Video, acoustic, and magnetic modules are expected shortly. There is also a sensor interface port for incorporation of chemical, biological, and other specialized sensors. http://www.betterroads.com/articles/feb03b.htm , http://www.sri.com/working/microsensors.pdf , http://www.sensorsmag.com/articles/0102/10/main.shtml

Ultrasonic Anemometer - The Solent Research R3-50 is a cost effective solution for projects requiring the accurate wind measurements. Ultrasonic anemometers use acoustic principles to measure wind speed and direction. Applicable for all weather applications. http://www.gill.co.uk

XI. Compound Specific Stable Isotope Analysis

Compound Specific Stable Isotope Analysis - Compound-specific stable isotope analysis is quickly changing the face of earth and environmental sciences. The types of questions now being routinely asked and answered by geochemists used to belong only in their wish lists from a decade or so ago. The impact is felt most in biogeochemical and environmental research, which themselves are fields undergoing tremendous evolution. Basic and applied questions pertaining to pollutant fate and transport, and renewed interest on paleo- and modern surface environments continue to demand more definitive methods of investigations. Gas and liquid chromatography are among the time-tested instruments utilized in biogeochemical investigations. The marriage of these techniques with high-precision stable isotope mass spectrometry has resulted in the critical ability to trace the sources and pathways of a wide variety natural and anthropogenic organic compounds. Common studies trace the sources and fate of biogenic and anthropogenic organic compounds in surface and groundwater systems using compound-specific stable isotope measurements. The study of lipid classes (especially fatty acids) allows us to delineate energy flow and carbon transfer from primary producers to the food web, thus giving us essential information on trophic structure and linkages in modern and paleo-ecosystems. http://www.gla.ac.uk/centres/surrc/compiso.html , http://www.research-projects.unizh.ch/math/unit70600/area695/p3637.htm , http://www.eom.slu.se/icobte/additional/SYMP8pZwank.doc , http://www.skio.peachnet.edu/projects/OrganicBio/lipid_bio.html

XII. High Performance Liquid Chromatography (HPLC)

High Performance Liquid Chromatography (HPLC) -HPLC is a popular method of analysis because it is easy to learn and use and is not limited by the volatility or stability of the sample compound. This user's guide provides the HPLC's history and evolution from the 1970's to the 1990's, and provides applications of modern HPLC, including separation, identification, purification, and quantification of various compounds. New hand portable, in situ HPLC systems are available. http://www.pharm.uky.edu/ASRG/HPLC/hplcmytry.html

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