Detector chemical

The lower vertebrates then possessed a useful nasal device which had already been utilised by their predecessors as a social chemical detector. Air breathing meant that their nasal air-flow was relatively weak in the absence of the pulling power exerted by lungs which... 

For less well defined incidents however, these detection systems may be inadequate. Portable chemical detectors may not be able to be deployed to the site, not detect the agen, or give inconclusive results. Clinical findings may be non-specific, present in an atypical manner, or for example in the case of sulphur mustard, have a latency period that delays firm pattern recognition. Due to the physico-chemical properties of the agent or the time between release and collection, environmental samples may have low agent levels or sufficiently high contaminants to prevent adequate results. 

Lightweight Chemical Detector (LCD-S) The LCD-S acts as a local warning alarm system for individuals and small groups of persons within the domestic or military market. It simultaneously detects, identifies, and differentiates between type of chemical warfare agent at below attack concentration, and warns users when to don personal protective equipment. 

Chemical. Exquisitely sensitive chemical agent sensors are available, but work best under laboratory conditions. Environmental chemical sensors suffer many of the same issues as biological detectors. They lack sensitivity, are not sufficiently mobile or flexible, and require trained users. Several types of chemical detectors are in use and are mentioned above. 

OFDs can be divided into two subclasses (1) optical fiber chemical detectors (OFCD) which detect the presence of chemical species in samples, and (2) optical fiber biomolecular detectors (OFBD) which detect biomolecules in samples. Each subclass can be divided further into probes and sensors, and bioprobes and biosensors, respectively. As a result of the rapid expansion of optical research, these terms have not been clearly defined and to date, the terms probe and sensof have been used synonymously in the literature. As the number of publications increases, the terminology should be clarified. Although both probes and sensors serve to detect chemicals in samples, they are not identical. The same situation exists with bioprobes and biosensors. Simply, probes and bioprobes are irreversible to the analyte s presence, whereas sensors and biosensors monitor compounds reversibly and continuously. 

Chemical detectors can and are using filters in mine detection to do a similar function, to concentrate samples, and also to separate the rough and tumble of field sampling from the analysis step. The various companies use different solutions, but inevitably they have to have a holding stage followed by a quick release into the detector. Like the cold finger and flash heater of commercial chemical analyzers. 

VJ What is important in the project we discussed is that, to my mind, it indicated what chemicals had staying power in soil and spread out certain distances using plants, rain, wind, and diffusion to be picked up by an animal or chemical detector under real world conditions. In the test, the dogs were trained to find only TNT and nothing else. Because Fido could find more chemicals, it could afford to lose on straight TNT detection in this real-world test. 

Fisher, M. and J. Sikes. Detection of landmines and other explosives with an ultratrace chemical detector. NATO e-Nose Conference, Coventry UK, October 2003. 

Chemical detectors. 2. Explosives—Detection. 3. Terrorism—Prevention. 

It is expected that the intermacromolecular complexes display entirely new physical and chemical characteristics different from those of the individual polymer components. So the following applications are, for example, considered membranes for dialysis, ultrafiltration, fuel cells and battery separators, wearing apparel, electrically conductive and antistatic coatings for textiles, medical and surgical prosthetic materials, environmental sensors or chemical detectors, and electrodes modified with specific polymers. 

Another promising avenue for research that Is unquestionably at the frontier of science concerns development of an understanding of processes Involved In olfactory perception. We know from our research on the sex pheromones that male moths possess a phenomenal ability to perceive and respond behavlorally to Incredibly minute quantities of pheromonal compounds In the air. The chemoreceptive sensitivity of this detector system Is certainly unrivaled by any organic-chemical detector system devised by man. 

Figure 30. CAMDS munition unpack area with chemical detector and bubbler...

Acoustic surface wave devices. 2. Detectors. 3. Chemical detectors. 4. Biosensors. I. Ballantine, David Stephen. II. Series. TK5984.A38 1996 96-21931... 

Chemical Detectors.—It is recognized that some men have a much more highly developed siense of smell than others and are hence able to detect in low couccntration.s that others fsul to perceive at all. To eliminate the hviman equation in detection of the presence of gas, considerable effort has been made, both during the World War and since, to devise... 

ISCAD The IMS/SAW chemical agent detector (ISCAD) is an NRL program outside the Joint CBD Program. It strives for ultralow false-alarm rates by integrating two CW point detection technologies (IMS and SAW) that have orthogonal principles of operation. The objective is a handheld chemical detector with subsecond equilibrated chemical detection at threat levels for survey mode and vehicular applications. The ISCAD incorporates NRL s pCAD, which dramatically improves SAW signal kinetics and tolerance to environmental effects. 

Civilian specialized teams that are prepared for working in chemically contaminated focal points are usually provided with different types of chemical detectors and monitoring kits, which are only capable to point to the presence or absence of the suspected chemical substance or a class of chemical. The most-used detectors are designed for detection of organophosphate pesticides, chlorine and cyanide, but the detectors against classical CW agents are usually not available to civilian chemists. Because, currently, the anti-terrorist activities have spiralled upwards, much of todays s military technology has been developed into commercially available equipment, however, the cost of detection equipment items... 

In the military environment, chemical detectors are often deployed to confirm that decontamination has been completed before casualties are passed via an air-lock into a Collective Protection Environment . The reason for this is obvious staff in the Collective Protection Environment do not wear personal protective equipment (PPE) and must be protected by rigorous maintenance of an uncontaminated environment. The Chemical Agent Monitor (CAM) is particularly suited for detecting vapour given off by unremoved areas of liquid contamination. However, proper monitoring of patients takes several minutes and in a mass-casualty or mass-decontamination setting this may not be feasible. Reliance must, therefore, be placed on the adequacy of the decontamination process itself. 

If chemical agent detector dogs are demonstrated to be able to reliably detect CWM at very low concentrations, this capability could be applied to assessing large CWM burial sites. For example, it is to be expected that some of the sites, or portions of some of the sites, are free of chemical agent because no CWM was buried in that section of the burial or only empty CWM containers were buried there.8 If chemical detector dogs could reliably confirm the absence of CWM, the excavation and removal of objects from portions of the burial pits so identified could possibly be carried out with reduced personal protective equipment and without other precautions normally taken for CWM excavation (negative pressure enclosures, for example). 

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