Contaminated Water Treatment
This method offers a way of processing and recycling liquids to remove contaminants. The two-step process provides a contaminant treatment pouch, called a “urine cell” or “contaminant cell,” that converts urine or another liquid containing contaminants into a fortified drink, engineered to meet human hydration, electrolyte, and caloric requirements.
In-Situ Removal of PCBs from Sediment Systems
A method for the in-situ removal of PCBs found in sediment systems consists of a redeployable polymer blanket that attracts and absorbs PCBs. A two-step approach removes and treats the PCBs. The blanket can then be decontaminated, refilled with fresh solvent, and deployed again for use in rivers, streams, harbors, lakes, and canals.
Activated Metal Treatment System (AMTS) for Paints
The AMTS treats PCBs in paints, and consists of a solvent solution that contains an activated zero-valent metal. AMTS is first applied to the painted surface using a spray-on or wipeon technique. The solution then extracts the PCBs from the paint. The extracted PCBs react with the microscale activated metal, and are degraded into benign byproducts.
Emulsified Zero-Valent Iron (EZVI)
The EZVI process involves placing nanoscale zero-valent iron particles into a surfactant-stabilized, biodegradable oil-in-water emulsion. Contaminants are pulled into the emulsion where the contaminant reacts with the zero-valent iron. The contaminants are degraded into ethene and other hydrocarbons that are broken down through biological activities in the subsurface.
Plant Chlorophyll Content Meter
A handheld plant stress detector measures the amount of chlorophyll in foliage, based upon light reflected from the plant. It collects light reflected from a target plant, separates it into two different wavelength bands (red and infrared), and analyzes the reflected light to determine plant physiological stress. It is used to learn how leaf chlorophyll content is affected by nutrients, biological influences, herbicides, and other environmental impacts.
Overview
The document describes a NASA-developed hand-held chlorophyll content meter designed to detect plant stress by measuring chlorophyll levels in foliage. This innovative device utilizes a unique algorithm that combines radiance from a plant and reference radiance to compute a numeric indication of the plant's stress level. It employs two optical filters—one for infrared and one for red light—to analyze the reflected light from plants, which correlates with chlorophyll content. The device operates by first calibrating against a standard reflectance target and then taking readings from the plant of interest.
Key features of the chlorophyll content meter include its compact and lightweight design, weighing only one pound and measuring 1 x 4 x 2.5 inches. It is user-friendly, requiring no physical contact with the plant, and can analyze a single leaf from 18 inches away or an entire tree from 20 yards. The device is also adaptable for remote sensing applications and can be manufactured at a low cost using commercially available components.
The technology is particularly beneficial in agriculture, precision farming, horticulture, and plant research. It allows for the early detection of plant stress caused by factors such as drought, pests, or chemicals, enabling timely interventions to promote healthier plant growth. By monitoring plant stress, the device can help reduce the excessive use of agricultural chemicals, thereby minimizing environmental concerns and groundwater contamination.
The meter's reflectance-based method is distinct from existing transmittance and fluorescence-based systems, which require physical contact with the plant or specific light conditions. Tests have shown that this technology can detect plant stress up to 16 days before any visual indicators, such as color changes, become apparent. The device provides immediate results that correlate well with other methods, making it a valuable tool for researchers and agricultural professionals.
Overall, NASA's chlorophyll content meter represents a significant advancement in plant health monitoring technology, offering a fast, accurate, and non-invasive means to assess plant stress and improve agricultural practices.
