Release detection approaches

Release Detection Approaches for Modern Tank Systems... 

There are three methods of release detection that are associated with modem tank systems.18,22 The first approach is to conduct an annual tank or line tightness test to detect small releases and to use more frequent monitoring by another method to detect large releases. All tank and line tightness tests must be performed at least once a year and must be able to detect leaks of 0.38 L/h (0.1 gal/h). In all cases where annual tightness tests are used, the regulation requires an additional form of leak detection in which tests on tanks are conducted at least monthly and those on pressurized lines at least hourly this ensures the detection of excessively large releases. For tanks, daily inventory records must be reconciled monthly, for pressurized lines, leaks of up to 11.4 L/h (3 gal/h) must be reliably detected. 

Research and development FTA has increased the funding of its safety- and security-related technology research to enhance a systems approach to the problem of release detection and management, including modeling and simulation to identify... 

A new approach to study root exudation of distinct compounds in soil-grown plants uses inoculation of roots with genetically engineered reporter bacteria, which are able to indicate the presence of particular compounds by indicator reactions, such as production of ice-nucleation proteins. This technique has been employed to detect the release of amino acids from roots of soil-grown A vena harbata (56). 

A specific approach for the measurement of base damage to DNA involves the hydrolysis of DNA into monomeric units. Acidic hydrolysis leads to the release of bases while enzymatic treatment yields nucleosides. The resulting mixture of lesions together with the overwhelming presence of normal bases or nucleosides is resolved by chromatography. The targeted damage is then quantified by use of specific detection systems. 

Stimulation for 24 hours with LPS leads to the release of interleukin-1 [3, IL-6, IL-8, TNF-a and by prolonging the incubation period from 48 to 72 hours, the whole blood model can detect the release of other lymphokines [45], including IL-2, IL-4, IL-13 and IFN-y. Skewing of the T-helper cell response to antigens can likewise be detected by evaluating the pattern of cytokine release, corresponding to a predominance of Th 1 or Th2 cytokine production. The predictive value of these approaches is currently under investigation. 

With respect to the considerations above, research is split into three parts. The first is connected to the kinetic description of the release of ammonia from the biomass as function of temperature. This research employs infrared spectroscopy using a tunable diode laser. Here very small biomass particles are used that are heated up very rapidly in a small reactor, which ensures that transport effects are virtually excluded from the kinetic release effects. Since ammonia is released in very small quantities it is quite hard to detect. Therefore, we first measure CO release, which is easier. In the second part we investigate the propagation of a conversion front in biomass layers. Here we perform experiments and try to establish a modeling approach for the propagation by analytical and numerical approaches. In the third part the gas-phase conversion processes are described in terms of... 

The ability to coat paramagnetic beads with antibodies to surface antigens of bacteria has been exploited to separate and concentrate organisms from the sample. The bacteria can then be lysed, and the DNA released into the supernatant can be amplified by PCR. Such an approach has found a wide range of applications, among which is the detection of Helicobacter pylori in water and stool specimens (El). 

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