60 results about "Ultraviolet visible spectroscopy" patented technology

A system and a method for calculating and assigning an indicative value, such as cetane number, pour point, cloud point and aniline point, of a fraction of an oil sample based on an index calculated and assigned from ultraviolet visible spectroscopy data of the oil sample.

A system and a method for calculating the cetane number, pour point, cloud point and aniline point of a gas oil fraction of crude oil from the density and ultraviolet visible spectroscopy of a sample of the crude oil.

A system and a method for characterizing a crude oil sample from the weight and ultraviolet visible spectroscopy of the sample, including calculating a crude oil ultraviolet visible index and using the index to calculate the API gravity and the aromaticity of the sample.

A system and a method for characterizing an aromaticity value of a crude oil sample from the weight and ultraviolet visible spectroscopy of the sample id provided. The system and method includes calculating and assigning a crude oil ultraviolet visible index and using the assigned index to calculate and assign an aromaticity value of the sample, and optionally to calculate and assign an API gravity.

The invention relates to a high-pressure ultraviolet visible near-infrared spectroscopy device for online monitoring of a supercritical system. The high-pressure ultraviolet visible near-infrared spectroscopy device comprises a high-pressure reaction kettle, a controller, an ultraviolet visible near-infrared spectrometer or an ultraviolet visible spectrometer and a computer, wherein the ultraviolet visible near-infrared spectrometer or the ultraviolet visible spectrometer is connected with the computer through a conducting wire, the high-pressure reaction kettle is arranged in a sample bin of the ultraviolet visible near-infrared spectrometer or the ultraviolet visible spectrometer, and the high-pressure reaction kettle is connected with the controller through the conducting wire. The high-pressure reaction kettle is communicated with a high-pressure injection pump and a sample introduction metering pump through a feed valve, a sample pipe and a gas-liquid three-way valve, which are mounted on a pipeline, and communicated with a nitrogen bottle and a vacuum pump through an exhaust valve and a gas three-way valve which are mounted on the pipeline. The high-pressure reaction kettle of the high-pressure ultraviolet visible near-infrared spectroscopy device provided by the invention has the advantages of reasonable design, convenience in use, accurate monitoring and the like, and can be used for online monitoring of physical conversion and chemical reaction processes under supercritical conditions.

The invention discloses a method for determining a melamine content by using ultraviolet spectroscopy. The method comprises steps of preparing a Tris-HCl buffer solution with a pH value of 4 to 10; preparing a melamine solution of 0 to 10 [mu]g / L, a DNA solution of 1.0 x 10<-5> to 1.5 x 10<-4> mol / L and a mixing solution of the melamine and DNA by using the Tris-HCl buffer solution, and determining absorbance of each solution using a blank reagent as a reference; establishing a working curve using a melamine concentration as an abscissa, and using differences between the DNA absorbance and the absorbance of the mixing solution of the melamine and the DNA as an ordinate; and adding a to-be-measured melamine liquid into the DNA solution, determining the absorbance, calculating the melamine concentration in accordance with the working curve, and converting the concentration into a corresponding melamine content in the to-be-measured liquid. The method employs an ultraviolet spectrum detection technology established on the basis of interactions of the melamine and deoxyribonucleic acid, and is accurate, simple, convenient and repeatable.

The invention discloses a light path of an ultraviolet visible spectrophotometer. The light path comprises a light source reflector for reflecting a light source into a horizontally linear light path, wherein a first reflector is arranged at the tail end of the horizontally linear light path and used for reflecting the horizontally linear light path into a 30-degree linear light path; a grating is arranged at the tail end of the 30-degree linear light path and used for reflecting the 30-degree linear light path into a 50-degree linear light path; and a second reflector is arranged at the end of the 50-degree linear light path and used for reflecting the 50-degree linear light path into a vertically linear light path vertical to the horizontally linear light path. The finally obtained vertically linear light path is a finally used light path; the light route is short, the energy loss is reduced, the energy is 5 to 10 times that of the conventional spectrophotometer, and the light spot is reduced by 4 to 5 times; the spectrophotometer can be used for analyzing 20 mu L of trace nucleic acid; and the generality is high.

A system and a method for determining one or more distillation temperatures for one or more given distillation weight percentages of a crude oil sample are provided, which can be used to produce a simulated distillation curve. Simulated distillation temperatures of crude oil samples are assigned as a function of density and data derived from UV / Visible spectroscopy measurement of the crude oil samples.

A system and a method for calculating and assigning an indicative value, such as cetane number, pour point, cloud point and aniline point, of a fraction of an oil sample based on an index calculated and assigned from ultraviolet visible spectroscopy data of the oil sample.

A system and a method for determining one or more distillation temperatures for one or more given distillation weight percentages of a crude oil sample are provided, which can be used to produce a simulated distillation curve. Simulated distillation temperatures of crude oil samples are assigned as a function of density and data derived from UV / Visible spectroscopy measurement of the crude oil samples.

The invention relates to a measuring method for wavelength indication errors of an ultraviolet and visible spectrophotometer to overcome problems in measurement of any wavelength indication error of the ultraviolet and visible spectrophotometer The method comprises the following steps: calibrating the wavelength of a fiber optic spectrometer and allowing light emitted by the ultraviolet and visible spectrophotometer to converge to light guide inlets of a seven branch-in-one optical fiber via reflection by a reflector lens of a 90-DEG corner lighting device and condensation by a convex lens of the 90-DEG corner lighting device and then to be introduced into the fiber optic spectrometer via the seven branch-in-one optical fiber; and adjusting the location of the 90-DEG corner lighting device in a colorimetric ware groove along a longitudinal direction to allow the spectral energy value of the fiber optic spectrometer to be maximized, fixing a hollow connecting rod into a pressing cap by a tightening a screw, and introducing the light emitted by the ultraviolet and visible spectrophotometer via the 90-DEG corner lighting device and the seven branch-in-one optical fiber into the fiber optic spectrometer for measurement, wherein a difference between the wavelength value of ultraviolet and visible spectrophotometer and a wavelength peak value measured by the fiber optic spectrometer is the wavelength indication error. The method provided by the invention is stable and reliable and has high measuring precision.

The invention discloses a water quality detecting system with a standard value comparison function. The water quality detecting system with the standard value comparison function comprises a first spectrum testing unit, a second spectrum testing unit and a power supply; each of the first spectrum testing unit and the second spectrum testing unit comprises a light source, a detecting probe and a spectrometer; the first spectrum testing unit and the second spectrum testing unit are respectively connected with a first industrial computer and a second industrial computer; both the first industrial computer and the second industrial computer are connected with a first master control computer; the first master control computer is connected with each of an alarm device, a first storage module and an instrument control module; the first master control computer is also connected with a second master control computer; the second master control computer is also connected with each of a second storage module, a first display module and a second display module. According to the water quality detecting system with the standard value comparison function, a physical detecting method based on ultraviolet visible spectrum detection is used; the problem of pollution is avoided; the other master control computer is added, so that whether various parameters exceed standards can be calculated and can be judged simply and clearly.