Abstract: A device is provided for capturing ionic metal species (e.g., Cd, Cu, Ni, Pb and Zn) dissolved in water. The device includes a nonporous polymeric tube for capturing the dissolved ionic metal species. The tube is formed from a membrane having transient cavities therein having an average pore size greater than 10 Å. A sequestration medium, contained within the tube, transforms the ionic metal species captured by the tube into a complexed, non-mobile metal species. The sequestration medium is capable of diffusing through the nonporous polymeric membrane at a controlled rate to form the complexed, non-mobile species and can comprise a mixture and metal complexing agent (e.g., a quinoline) and a long chain organic acid (e.g., oleic acid).

Abstract: A method is provided for detecting minerals and metal-containing materials which are located in sediment deposits on the sea floor and which exhibit an induced polarization response. In this method, a streamer cable is towed in the sea behind a ship. The cable has transmitters and receivers at the free end thereof and the cable is towed such that this free end is close to or trenches into the sea floor. The transmitters are used to transmit a square wave electrical current into the sediment of the sea floor while the receivers are used detect to any secondary signals produced by an induced polarization source located on or in the sea floor in response to the electrical current. The secondary signals are processed to determine measurement parameters characteristic of the source of the secondary signals so as to identify the source and using simultaneously acquired global positional data, to determine the location of the source.

Abstract: A collapsible bag sampler comprises a top section; a bottom section connected to the top section; a tail section having fins, which tail section is fitted onto the top section; a nose section with tray, which tray supports a flexible bag; a nozzle holder; a nozzle holder insert in the top section to hold the nozzle; and a flexible bag attached to the outside of the rear of the nozzle holder. Because the bag container is flexible and contains substantially no air, there are no limitations due to air compressibility, meaning the depth to which the sampler could be used would be limited only by the size of the intake nozzle and the volume of the bag. The transit rate is limited only by the apparent approach angle of the nozzle facing into the stream velocity as it makes its vertical descent and ascent (0.4 times the stream velocity). The sampler has a useful range of from 2.0 ft/sec to approximately 10 ft/sec stream velocities.

Abstract: A method of degassing a volume of supersaturated liquid is provided which comprises introducing a plurality of microbubbles of gas substantially near the bottom of the volume of supersaturated liquid so that the microbubbles percolate up through the volume of supersaturated liquid to thereby effect removal of dissolved gas in the volume of the supersaturated liquid at the top of the volume. In one embodiment, the step of introducing microbubbles comprises introducing the microbubbles by recirculating deionized water through a hollow fiber microfiltration membrane. In another embodiment, the step of introducing microbubbles comprises introducing the microbubbles through a pipe from the turbine of a dam. In most applications, the volume of supersaturated liquid is water and the microbubbles of gas comprise air. The volume of supersaturated water advantageously comprises a volume of a river, lake or stream which is near a dam with a turbine.

Abstract: An apparatus for and a process of evaluating well bore flow of water and for sampling of water within a well. A hose is inserted into the well to a known depth. To evaluate the water, a tracer fluid is introduced into the hose until the pressure within the hose exceeds the hydrostatic pressure at the known depth by a preset amount. The tracer fluid is then rapidly released into the well. The tracer fluid is detected in water pumped from the well, and the elapsed time between release of the tracer fluid into the well and detection of the tracer fluid in the water pumped from the well is determined. The process is repeated at a second known depth, and the tracer fluid travel time between the two depths is determined. From this and the cross-sectional area of the well, the incremental volumetric well bore inflow to the well between the two depths is calculated. The process can be repeated at several depths within the well to permit construction of a velocity profile of water movement within the well.

Abstract: A device is provided for removing and concentrating neutral mercury species from air and water. The device includes a nonporous polymeric membrane, preferably in the form of a flattened tube, for capturing and removing the neutral mercury species from the environment and a sequestration medium contained within the tube for transforming the neutral mercury species captured by the tube into a stabilized mercury species. The sequestration medium can comprise an acidic oxidant for transforming the neutral mercury species into a ionic soluble mercury species or a complexing agent for transforming the mercury species into a complexed soluble mercury species. The nonporous membrane can be made of a number of different synthetic polymers including polyethylene. The device is ideally suited for the passive integrative sequestration of neutral mercury species from a wide variety of environments.

Abstract: An acoustic travel time tomography system enables determining of physical properties of a dam, or a like concrete mass. The system includes a plurality of acoustic sensors, positioned on the dam at a plurality of spaced sensor locations which are known relative to each other, for producing output data responsive to the detection thereby of acoustic waves generated in the dam. An impact source produces an impact at an impact location which is known relative to the sensor locations so as to generate acoustic waves in the dam for detection by the sensors. A data processing unit acquires output data from the sensors produced responsive to acoustic waves generated by the impact source and analyzes this output data, together with data related to the relative locations of the sensors and the impact source, to determine physical properties of the dam.

Abstract: An electrodialysis system for desalting water is powered from a direct current power source. The system includes solenoid activated reversing controls and incorporates features which enable the system to operate unattended for continuous (24 hours per day) periods while still using minimal power. A microcontroller unit and a field circuit board control all reversing functions and fail-safe modes. The flow control portion of the system provides for flushing the system electrodes with product water so that chlorine gas generated during the electrodialysis process is picked up by the product water stream.

Abstract: A method of monitoring the quality of water at a ground water sampling site without human intervention. Water at the sampling site is purged until at least one preselected purge criterion is satisfied. At least one water quality attribute is automatically measured at the sampling site, and the quality of water at the site is determined based on the measured water quality attribute. The method is performed by a system including a control unit which, in accordance with a computer program, controls the taking of water quality attribute measurements at the sampling site. The control unit may be equipped with a port for downloading data to a technician on site and with a transceiver for communicating data to a base station via a communications network.

Abstract: A method is provided for enhancing oxidation of methyl bromide during agricultural fumigations of fields using a fumigant containing methyl bromide. The method comprises adding a methylotrophic bacterium to the soil in an amount effective to provide bacterial oxidation of the methyl bromide. The bacterium preferably comprises a bacterium isolated from agricultural soil, and, in a specific embodiment, comprises a 16S ribosomal RNA gene sequence in the Alpha subgroup of Proteobacteria designated strain IMB-1 (ATCC 202197). The fumigant also includes chloropicrin in an amount reduced to a level which permits said bacterial oxidation but while still enables the chloropicrin to serve as a warning agent for excessive release of methyl bromide from the soil. The soil can be pretreated with methyl iodide. The bacterium is applied to the soil as freeze-dried bacterial cells during the fumigation operation.

Abstract: A method is provided for producing L-ascorbic acid (Vitamin-C) in a single process step. Starting material, particularly a mixture of compounds from the group consisting of glucose, sorbitol, sorbose, and 2-keto-L-gulonic acid, is catalytically oxidized in aqueous solution by hypochlorous acid. L-ascorbic acid then can be separated from the aqueous solution, and the unconverted reactants recycled for greater conversion. The reaction occurs in the aqueous state at ambient temperature near a pH of 5.5 when an optimum amount of hydrous cobalt-oxide is present in the solution.

Abstract: A chemical metering and control system is provided which maintains a desired level of a pesticide (or other chemical) in any open or closed channel flow stream with fluctuating flow rates. The system dispenses an amount of the pesticide at an injection point of the flow stream along with a fluorescent indicating dye, and then takes a sample downstream from the injection point to determine how much of the indicating dye is present in the flow stream, and therefore how much pesticide is present. At the sampling point a pump extracts a flow stream sample and passes the sample to a fluorometer which measures the amount of fluorescent indicating dye injected upstream. A proportional integral derivative (PID) controller then adjusts the level of the pesticide/dye mixture in order to achieve the appropriate concentration of pesticide in the flow stream.

Abstract: A water denitrification process is provided which comprises stopping the reduction of nitrate at nitrite, lowering the pH of the water, and then gas stripping the nitrite out of the water by using air as the gas in a sparger. This allows considerable savings to be realized based on the reduced chemical removal costs as compared to other water denitrification processes.

Abstract: A method is provided for producing feed particles of a desired size in a 20 to 1000 .mu.m size range for uses such as a larval aquatic feed. The method uses a marumerizer comprising a cylindrical housing have a grooved bottom, and includes the steps of placing a wet mash of the particle material (e.g., a larval aquatic feed material) in the marumerizer, placing in the marumerizer a charge of inert beads of a size (e.g., 3 mm) substantially larger than that of the particles to be produced, and rotating the marumerizer with the wet mash and charge of inert beads therein so that the beads compact and shape the mash into formed spheroidal particles.

Abstract: A system and method for providing analysis and evaluation of penetration test data for modifying Becker Hammer drill programs while in progress by measuring the bounce chamber pressure of a diesel hammer. The system comprises a pressure transducer connected to the bounce chamber for sensing the bounce chamber pressure, a data logger for monitoring the pressure transducer, storage means, a control module and a keyboard having a display screen to enable user control of the data logger, a telephone modem, and a series of instructions for controlling the schedule, pressure transducer measurement, control module signal monitoring, computation of data, and data storage operations of the data logger.

Abstract: A sampler for obtaining an isokinetic sample of a flowing fluid. A liquid-filled, fluid-tight container has a deflated bag within it. The sampler is positioned within the flowing fluid stream, and the liquid is pumped from the container at a rate proportional to the flow rate of the flowing fluid to draw a sample of the fluid into the bag at the same rate as the flow rate of the flowing fluid. When the bag is filled it can be removed from the container and the container inlet tube replaced, allowing the sampler to be used for another sample without laborious cleaning in the field.

Abstract: A sampler for obtaining an isokinetic sample of a flowing fluid. A liquid-filled, fluid-tight container has a deflated bag within it. The sampler is positioned within the flowing fluid stream, and the liquid is pumped from the container at a rate proportional to the flow rate of the flowing fluid to draw a sample of the fluid into the bag at the same rate as the flow rate of the flowing fluid. When the bag is filled it can be removed from the container and the container inlet tube replaced, allowing the sampler to be used for another sample without laborious cleaning in the field.

Abstract: Metallic forms of gold and other precious metals can be dissolved and transported (mined) using an aqueous sulfide-bearing leach solution. Maximum sulfur fugacities are achieved in sulfide-bearing solutions under approximately neutral pH and relatively reducing conditions. The optimum chemical conditions are achieved specifically by heating an aqueous sulfide solution such as NaHS, Na.sub.2 S, H.sub.2 S, (NH).sub.4 S, or other suitable forms to temperatures of at least about 100.degree. C. in the presence of excess elemental sulfur. The sulfide dissociates in the solution to form aqueous sulfide species including polysulfide and HS.sup.- which lixivate gold and other precious metals.

Abstract: An apparatus and method for soil remediation replaces specific ions in the soil electrochemically, using a DC voltage source and special multicompartment anodes and cathodes, each comprising an inner compartment containing electrolyte and a submerged electrode, a salt bridge connecting the electrolyte to an outer compartment containing a specific solution with replacement ions for soil remediation, and a membrane holding in the replacement solution. The membrane is put into contact with the soil, allowing electrical contact and ion migration while keeping the solution inside the anode or cathode. The multicompartment structure prevents the hydroxide and hydronium ion emplacement that causes acid and base fronts to form.

Abstract: An ion exchange process utilizes a chemical system in which sodium nitrate is reacted with an acidic solution of urea to selectively precipitate nitrate ions from waste brine in the presence of chloride ions, thereby allowing for the recycling of the brine regenerant.