G01N33/0057

Method for detecting organic and inorganic explosives

Methods, devices, and systems are disclosed for releasing a sample from a carrier medium. A method of releasing a sample from a carrier medium comprises treating a sample on a carrier medium with a first organic reagent, wherein when the sample contains at least one inorganic salt, the first organic reagent binds to a cation of the inorganic salt to produce both a first volatile compound and an isolated anion of the inorganic salt; treating the sample on the carrier medium with a second organic reagent, wherein the second organic reagent reacts with the isolated anion to produce a second volatile compound; and releasing the treated sample from the carrier medium, wherein when the first and the second volatile compounds are produced, the releasing step releases at least one of the first and second volatile compounds from the carrier medium.

EXPLOSIVES DETECTION USING OPTICAL SPECTROSCOPY
20170299521 · 2017-10-19 ·

A method for determining whether a sample includes a nitrate-based explosive comprises receiving the sample and selecting an area of interest on the sample. Then, at least a portion of the area of interest is interrogated with an optical source to produce a spectrum with an amplitude. The amplitude of a first portion of the spectrum is compared to a first predetermined threshold to determine if the sample includes a nitrate. After determining that the sample includes a nitrate in the area of interest, the amplitude of a second portion of the spectrum is compared to a second predetermined threshold to determine if the sample includes a secondary indicator. Then, an indicator is activated based on the determinations.

2H/1T Phase Contact Engineering for High Performance Transition Metal Dichalcogenide Chemical Vapor Sensors

A method of making a low dimensional material chemical vapor sensor comprising providing a monolayer of a transition metal dichalcogenide, applying the monolayer to a substrate, applying a PMMA film, defining trenches, and placing the device in a n-butyl lithium (nbl) bath. A low dimensional material chemical vapor sensor comprising a monolayer of a transition metal dichalcogenide, the monolayer applied to a substrate, a region or regions of the transition metal dichalcogenide that have been treated with n-butyl lithium, the region or regions of the transition metal dichalcogenide that have been treated with n-butyl lithium have transitioned from a semiconducting to metallic phase, metal contacts on the region or regions of the transition metal dichalcogenide that have been treated with the n-butyl lithium.

Multi-substrate passive colorimetric sensors for detecting toxic industrial chemicals and chemical warfare agents

Disclosed are systems and methods for the robust passive detection of airborne toxins using a colorimetric sensor coating onto a optically transparent substrate. In certain embodiments, the substrate is affixed to an adhesive material (tape). In certain embodiments, the sensor and substrate are transparent. In various embodiments, multiple sensors are coated onto selected substrate for the simultaneous detection of multiple toxins. In various embodiments, the sensed or detected toxins include a number of chemical warfare agents and toxic industrial chemicals. In various implementations, the tape is affixed to a remote surface, which may be visually monitored by a camera directly by focusing the camera on the tape or may be affixed to a camera lens by an adhesive backing, such that colorimetric sensor changes may be observed through the lens itself. Sensor claddings consist of optical grade polymers immobilized with colorimetric and/or fluorescent indicators that undergo optical changes upon exposure to their target analyte. Typical substrate cross-linked polymers are urethane acrylate polymer based, co-polymerized with silicone backbone such as dimethyl siloxane, which in general is chemically inert, yet leaves the polymer with the large free-volume necessary for rapid target diffusion. The polymer is cured after immobilization with target indicator mixture, and simultaneously cross-linked by UV light or heat.

SYSTEMS AND METHODS FOR GAS PRE-SEPARATION FOR DETECTION OF SUBSTANCES
20170274316 · 2017-09-28 ·

The present disclosure is directed to methods and systems for detecting a substance in a sample gas. The methods and systems include separating the substance of interest in the sample gas, and introducing the separated sample gas into a detector. The systems and methods further include performing an analysis of the substance of interest.

GAS ACCUMULATION AND COMBUSTION CONTROL DEVICE
20220049863 · 2022-02-17 ·

A gas accumulation and combustion control device combining a sorption system, a ventilation system, a control system, and sensor system, with the sensor system configured to detect gas contaminants, transmit a gas detection signal to the control system, the control system configured to adjust the ventilation system based on the gas detection signal, the ventilation system configured to draw the contaminated air in from the atmosphere and lead it toward the sorption system, which in turn is configured to adsorb or absorb the gas contaminants.

METHODS AND SYSTEMS FOR CHEMICAL VAPOUR SENSING

Embodiments relate generally to methods, systems, devices and applications for use in relation to the detection of chemical vapours. A particular embodiment relates to a device for chemical vapour sensing. The device comprises a housing of a size to be manually portable, the housing defining a plurality of receptors adapted to receive a respective plurality of manually replaceable chemical vapour sensing components. The device further comprises at least one signal receiver to receive data signals from each chemical vapour sensing component when the chemical vapour sensing component is positioned in one of the receptors.

Multi-Dimensional Cross-Reactive Array for Chemical Sensing
20170241910 · 2017-08-24 ·

The discrimination ability of a chemical sensing cross-reactive arrays is enhanced by constructing sensing elements in two dimensions, first in the x-y plane of the substrate, second in the z dimension so that the sensors are vertically stacked on top of one another. Stacking sensing elements on top of one another adds to the discrimination ability by enabling the characteristic measurement of how fast target chemicals are passing through the stack of sensors. The new invention also allows the ability to discriminate components in a sample mixture by separating them using their innate difference in diffusional rates. Multi-sensor response patterns at each z level of sensors and time delay information from the sample passing from one level to the next are used to generate the response vector. The response vector is used to identify individual component samples and components in a mixture sample.

Tube-in-a-tube electronic sensors

The present invention is directed to tube-in-a-tube electronic materials and electronic chemical sensors comprising tube-in-a-tube configurations such as covalently functionalized double-walled carbon nanotubes.

ANALYTICAL PROCESS FOR DETECTING PEROXIDE-, HALOGEN OXOANION-, NITRATE-, NITRAMINE-, AND NITROTOLUENE-BASED EXPLOSIVES
20220308027 · 2022-09-29 ·

The invention provides an analytical process, which preferably is a one-step process, for detecting in a sample peroxide-based explosives, nitrate-based explosives and/or nitramine-based explosives, the process comprising contacting a sample suspected of containing a peroxide-based compound, especially a peroxide-based explosive, a nitramine, nitrate ester or a nitrate salt, especially a nitrate-based explosive and/or a nitramine-based explosive, with a composition comprising a Ni-porphyrin, an acid and preferably an acid-stable solvent.