Systems, methods, and software that measure a plurality of error values each related to a different condition of an aquatic environment monitoring system including a degradation in a chemical indicator due to photo-aging, a degradation in a chemical indicator due to water-aging, a physical contamination of a chemical indicator, an illumination imbalance related to an optical reader, a degradation of a light source of an optical reader, a contamination in water between an optical reader and a chemical indicator, a displacement due to friction between a chemical indicator apparatus and a monitoring unit, an error intrinsic in a chemical indicator, and an error in distance between a chemical indicator and an optical reader. The plurality of error values are used to determine a confidence level that is compared to a threshold value associated with the monitoring system. A correction instruction is generated for correcting one or more of the conditions.

The invention is directed towards methods and compositions for identifying the presence of surfactants in water. The invention is quite superior over the prior art because it can form a colorful complex in half the time, avoid the need for difficult separation steps, use a safer solvent, and avoid the formation of messy foam. The invention involves adding to the water a cobalt thiocyanate reagent, pre-prepared from a cobalt salt and a thiocyanate salt, which forms a colorful complex with the surfactant. Chloroform is then added to the water. The cobalt reagent causes the virtually all of the surfactant to form a colored complex which rapidly migrates into the chloroform and prevents the surfactant from foaming. Once in the chloroform, a UV-vis spectrometer can easily and precisely identify the type and amount of surfactant that was in the water.

A method and analyzer for determining a measured value of a measured variable of process automation technology in a liquid or gaseous medium by means of an optical sensor includes taking a sample of the medium; mixing the sample with one or more reagents; supplying an emitter of the optical sensor with an exciter signal for producing sent light, wherein the sent light by interaction with the mixed sample is converted into received light as a function of the measured variable; producing a receiver signal by means of a receiver of the optical sensor from the converted, received light; and determining the measured value based on the receiver signal and a calibration function, which includes a term which takes aging of the reagents into consideration.

A personal-sized, portable explosive detection field test kit (ETK) and related methods of use. Embodiments of the disclosed ETK include a case having a closing system featuring three levels of closure which retain the case cover securely in a closed position until ready for use, while being easily opened when necessary. The ETK instructions are permanently attached to the case to prevent loss. The case includes retention features which retain the kit components until needed and protects them against loss or damage. The ETK includes one or more test tubes that are color coded and include abbreviated instructions.

The present invention provides methods for determining the presence of oxidizing salts. According to the current invention, analyte is collected on a swipe and subsequently heated to a temperature sufficient to release a detectible vapor phase component of the oxidizing salt. The vapor phase component passes reacts with a pH sensitive molecule. Reaction of the vapor phase product with the pH sensitive molecule produces a detectible change in response intensity.

A gas-phase detection system based on detecting optochemical and optoelectrochemical signals. The sensing platform is particularly powerful for detection of nitrogen oxides at low ppbV concentrations. The optochemical analysis is based on the color development due to a chemical reaction taking place in an optimized material. The electrochemical analysis can be based on the doping level or redox potential changes of an electrochemical sensor; and optoelectrochemical detection can be based on a combination of the electrochemical and optoelectrochemical methodologies. Each independent signal can be simultaneously detected, increasing the reliability of detection.

A method of calibrating a biological detector can include training a biological detector to detect a calibration compound, wherein the calibration compound comprises an odor that is detectable by the biological detector and is not used in an environment for which the biological detector is trained to detect odors, presenting the biological detector with a device comprising the calibration compound, and determining whether the biological detector will alert to the calibration compound.

Multi-parameter water analysis system with a holder removably engageable in an enclosable water chamber having an inlet and outlet in line with plumbing of an aquatic environment and allowing water from the aquatic environment to enter the enclosable water chamber for a chemical indicator of the holder to indicate a physical change via an optical reader, the holder configured to move with respect to the optical reader at least in part due to a motive force provided by the flow of water from the inlet in the enclosable water chamber.

A personal-sized, portable explosive detection field test kit (ETK) and related methods of use. Embodiments of the disclosed ETK include a case having a closing system featuring three levels of closure which retain the case cover securely in a closed position until ready for use, while being easily opened when necessary. The ETK instructions are permanently attached to the case to prevent loss. The case includes retention features which retain the kit components until needed and protects them against loss or damage. The ETK includes one or more test tubes that are color coded and include abbreviated instructions.

Various methods for determining whether a subject has alcoholic hepatitis are described. In one aspect, a method for determining whether a subject has alcoholic hepatitis is described. The method includes determining the levels of a trimethylamine in a biological sample obtained from the subject. The level of trimethylamine in the biological sample is compared to the control value, and the subject whose level of trimethylamine exceeds the control value is diagnosed as having alcoholic hepatitis. In another aspect of the present invention a method for assessing a subject as having alcoholic hepatitis (AH) includes determining the level of trimethylamine and the level of pentane in a biological sample obtained from the subject. A TAP score is determined based on the concentration of trimethylamine and the concentration of pentane. The subject is diagnosed as having alcoholic hepatitis if the TAP score exceeds a control value.