The invention relates to an apparatus for simultaneous online assay of nitrites and nitrates in water samples with improved sensitivity and accuracy, enhanced capacity of anti-interference against salinity, reduced assay costs, and simplified operation.

An optical nitrate sensor features a signal processor or signal processing module configured to: receive signaling containing information about a measurement (M) of UV optical absorbance of nitrate dissolved in water of a UV light that is generated by a UV LED centered at 229 nm and that traverses a confined volume of the water within a prescribed region of a sensor body, and also about a reference sample (R) of a portion of the UV light not traversing the confined volume of the water; and determine corresponding signaling containing information about the concentration of nitrate dissolved in the water, based upon the signaling received.

This method determines the amount of extracellular fluid surrounding a surface disposed inside a plant, the ion population in that fluid and the identity of the dominant ion in that fluid. The method has four parts: 1) Providing an electrochemical circuit between the surface and external electronics 2) Executing two electrochemical procedures which result in a sequence of measured charge transfer values, 3) Processing the measured charge transfer values into a value proportional to the of extracellular fluid surrounding the surface, a value proportional to the total ion population in the fluid and a value that identifies the dominant ion in the fluid, 4) Generating a set of time/quiescent potential pairs of values which are used to identify the dominant ion type in the extracellular fluid during different time ranges.

An intelligent method is designed for predicting the effluent ammonia-nitrogen concentration in the urban wastewater treatment process (WWTP). The technology of this invention is part of advanced manufacturing technology, belongs to both the field of control engineering and environment engineering. In order to improve the predicting efficiency, a recurrent self-organizing neural network, which can adjust the structure and parameters concurrently to train the parameters, is developed to design this intelligent method. This intelligent method can predict the effluent ammonia-nitrogen concentration with acceptable accuracy and solve the problem that the effluent ammonia-nitrogen concentration is difficult to be measured online. Moreover, the online information of effluent ammonia-nitrogen concentration, predicted by this intelligent method, can enhance the quality monitoring level and alleviate the current situation of wastewater to strengthen the whole management of WWTP.

A sensor for measuring a concentration of a particular ion, molecule or atom in a fluid includes a sample handling portion for providing at least some of the fluid, a first photo-detection device, and a first light source. The first photo-detection device is configured to measure a power of light incident thereon, and the first light source includes a solid-state light emitting device. The first light source is configured to emit light having a wavelength less than 240 nanometers incident on the fluid provided by the sample handling portion, and the first photo-detection device is configured to receive light having passed through the fluid.

A monochloramine microsensor includes an elongated housing defining a central axis and an open interior and having a capillary opening at one end. A semi-permeable membrane covers the capillary opening, the semi-permeable membrane allowing diffusion of chloramines there-through while preventing water from entering into the interior of the housing. A chloramine sensitive element in the form of a wire, fiber or nanotube is mounted within the housing, the chloramine sensitive element, when used in conjunction with an anode, outputs current in an amount proportional to the concentration of chloramine present in a liquid sample in which the chloramine sensitive element is immersed. The chloramine sensitive element extends along a length of the central axis to a first end adjacent to and spaced from the semi-permeable membrane. The chloramine sensitive element is a gold wire, a platinum wire, a carbon fiber or a carbon nanotube.

A total nitrogen measurement apparatus comprising an ultraviolet lamp comprising: a light emission section and a holding section for holding the light emission section, the holding section being formed of a material not including iron; a reaction vessel having a space where the light emission section is to be inserted and a sample water is to be contained around the light emission section for converting nitrogen compounds in the sample water contained in the reaction vessel into nitrate ions by oxidative decomposition using ultraviolet rays from the light emission section; and a measurement section configured to perform absorbance measurement on the sample water including the nitrate ions.

The present application provides a method for estimating abundance and distribution features of antibiotic resistance genes (ARGs) in surfacial sediments of lake and reservoir, including step 1 of obtaining an annual input total of nitrogen and phosphorus pollutants of each tributary flowing into the lake and reservoir; step 2 of constructing a linear regression equation between the abundance of each type of ARGs and the nitrogen and phosphorus discharge; and step 3 of calculating annual input total of nitrogen and phosphorus pollutants to be estimated for each geographical location of the lake and reservoir using inverse distance weighting interpolation analysis based on the annual input total of the nitrogen and phosphorus pollutants obtained in step 1, and substituting the calculated annual input total into the linear regression equation to estimate the abundance of each type of ARGs and analyze a distribution feature of the ARGs.

A sensor for measuring a concentration of a particular ion, molecule or atom in a fluid includes a sample handling portion for providing at least some of the fluid, a first photo-detection device, and a first light source. The first photo-detection device is configured to measure a power of light incident thereon, and the first light source includes a solid-state light emitting device. The first light source is configured to emit light having a wavelength less than 240 nanometers incident on the fluid provided by the sample handling portion, and the first photo-detection device is configured to receive light having passed through the fluid.

A detection system and method for simultaneously determining the concentration of ammonium and nitrate/nitrite in samples such as surface water and wastewater. The detection system and method herein can further comprise a cleaning loop and a calibration loop and can be used in situ and over long periods of time without replacement or frequent maintenance and upkeep.