摘要:
A microbial sensor, microbial sensing system, and method that can be used to determine the chemical environment of unsaturated soils, rhizosphere, and/or plants are disclosed. The microbial sensing system can be used for monitoring the health of plants including nutrients, salinity, contaminants, chemicals (pesticides, herbicides) and diseases. A microbial sensing system can include one or more indicator electrodes and a reference electrode. The microbial sensing system can include a signal acquisition and/or communication module to allow the real-time collection of data from field deployments and laboratory investigations.
摘要:
A lowerable-raisable ground water sampling device has an annular elastomeric seal for preventing the exchange of atmospheric gases with the ground water within a well casing. In its preferred form, the seal is a frusto-conical elastomeric disk mounted on the lower end of a water-extraction tube depending from the lower end of a water sampling unit. A fluid-actuator cylinder is floatable positioned on the tube for moving an annular wall structure downwardly against the disk upper surface, thus to decrease the cone angle of the frusto-conical surface to cause the outer edge of the disk to move out of sealing engagement with the well casing surface. When the fluid cylinder is depressurized, the frusto-conical disk automatically expands to seal against the well casing surface.
摘要:
A microbial sensor, system, and method that can be used to determine a chemical environment and/or substrate concentrations in anaerobic or aerobic environments, such as soils, sediments and ground waters, are disclosed. An exemplary system uses one or more (e.g., inert) measurement electrodes and a reference electrode. The reference electrode can include an electrode exposed to atmospheric oxygen (e.g., a cathode) or an electrode exposed to stable anaerobic or aerobic conditions. The exemplary microbial sensor system measures open-circuit voltage to characterize the chemical (oxidizing or reducing) environment and/or recovery voltage to measure substrate concentrations in the subsurface.
摘要:
A microbial sensor, system, and method that can be used to determine a chemical environment and/or substrate concentrations in anaerobic or aerobic environments, such as soils, sediments and ground waters, are disclosed. An exemplary system uses one or more (e.g., inert) measurement electrodes and a reference electrode. The reference electrode can include an electrode exposed to atmospheric oxygen (e.g., a cathode) or an electrode exposed to stable anaerobic or aerobic conditions. The exemplary microbial sensor system measures open-circuit voltage to characterize the chemical (oxidizing or reducing) environment and/or recovery voltage to measure substrate concentrations in the subsurface.
摘要:
A microbial sensor, system, and method that can be used to determine a chemical environment and/or substrate concentrations in anaerobic or aerobic environments, such as soils, sediments and ground waters, are disclosed. An exemplary system uses one or more (e.g., inert) measurement electrodes and a reference electrode. The reference electrode can include an electrode exposed to atmospheric oxygen (e.g., a cathode) or an electrode exposed to stable anaerobic or aerobic conditions. The exemplary microbial sensor system measures open-circuit voltage to characterize the chemical (oxidizing or reducing) environment and/or recovery voltage to measure substrate concentrations in the subsurface.
摘要:
A sampling device for sealed positioning within the casing of a well contains a stripping chamber for stripping a ground water sample of its volatile compounds at or near the point of collection. In one embodiment, the stripping chamber includes a piston which is raised above the top surface of the sample to create a head space, and an injector for injecting inert gas into the sample, causing the volatile compounds to be released into the head space, whereupon they exit the chamber via a vapor outlet duct leading out of the well. In a second embodiment, the stripping chamber includes a tube having a sidewall formed of a semi-permeable membrane, and an injector which injects an inert gas into the bore of the tube. The device may also include a sensor mounted within the stripping chamber, and a valve for directing a calibration gas into the chamber.
摘要:
Methods and systems for monitoring microbial activity and microbial communication in an environment are disclosed. Exemplary methods include measuring a high impedance voltage between a reference electrode and one or more measurement electrodes to monitor microbial activity. Microorganisms form a biofilm that attaches to at least one of the one or more inert measurement electrodes and that allows for measuring the microbial activity, characterizing the environment, and/or monitoring microbial communication in the environment.
摘要:
The ground-water sampler collects a time-averaged or composite sample of the ground water. The sampling system was designed to be self-contained and all sources of power being contained within the well casing. The sampler collects the sample on a sorptive media and the media analyzed by a laboratory. The sampling system prevents the exchange of gases between the ground water and the atmosphere. The exchange is prevented by a well packer which is designed to be placed in well casings of 2 inches or greater. The well packer can be easily and economically placed into the well casing with the use of a packer tool. The sampler is inserted into the well packer and once inserted a one-way check valve opens to the aquifer allowing the water to be sampled. After the sampling episode, the sampler is removed from the well packer and the one-way check valve closes. The media is then analyzed in a laboratory. In the alternative, the sorptive media unit can be replaced with chemical or physical analysis units making possible real-time analysis of the aquifer.
摘要:
Methods and systems for monitoring microbial activity and microbial communication in an environment are disclosed. Exemplary methods include measuring a high impedance voltage between a reference electrode and one or more measurement electrodes to monitor microbial activity. Microorganisms form a biofilm that attaches to at least one of the one or more inert measurement electrodes and that allows for measuring the microbial activity, characterizing the environment, and/or monitoring microbial communication in the environment.
摘要:
Methods and systems for monitoring microbial activity and microbial communication in an environment are disclosed. Exemplary methods include measuring a high impedance voltage between a reference electrode and one or more measurement electrodes to monitor microbial activity. Microorganisms form a biofilm that attaches to at least one of the one or more inert measurement electrodes and that allows for measuring the microbial activity, characterizing the environment, and/or monitoring microbial communication in the environment.