A thermal desorption tube collection system uses a thermoelectric cooler to collect and concentrate gas samples. In some modes, the operation of the cooler is reversed to flow the concentrated sample directly into a separator such as a gas chromatography system. Components resolved in time by a thermal desorption separator accumulate in a sample cell and are analyzed by electromagnetic radiation-based spectroscopic techniques. Also presented are methods for analyzing biogas samples.

A polyimide precursor solution contains a polyimide precursor, wherein in the case where the polyimide precursor is analyzed by gel permeation chromatography, the elution curve of the polyimide precursor has a region A including a higher-molecular-weight peak and a region B including a lower-molecular-weight peak; a weight average molecular weight determined from the region A in terms of polystyrene is approximately 10,000 or more, and a weight average molecular weight determined from the region B in terms of polystyrene is approximately less than 10,000; and when the area of the region A is a and the area of the region B is b, the polyimide precursor satisfies Equation (1)
a/(a+b)=approximately from 0.70 to 0.98.  Equation 1:

A cloud server platform end is used to construct a mass spectrum species classification model, extract a mass spectrum data feature, and construct a training model of the convolutional neural network; a user platform end is used to upload the mass spectrum, experiment condition and device data, directly screen and identify the type of the mass spectrum based on the mass spectrum species classification model or the mass spectrum information base, automatically compare and identify the species and name of the pesticides based on the neural network model trained by the cloud server platform end, and feedback the comparison result to the user. The disclosure solves the restriction on the purchase of standards for user, the use of the system is not limited by the location, and the pesticide residues could be detected automatically, quickly and accurately.

The present invention relates to a novel analysis device and method for obtaining the concentration of dissolved inorganic carbon (DIC) and isotopic carbon and oxygen concentration thereof, continuously from a liquid sample.

Components resolved in time by a thermal desorption separator accumulate in a sample cell and are analyzed by electromagnetic radiation-based spectroscopic techniques.

Components resolved in time by a thermal desorption separator accumulate in a sample cell and are analyzed by electromagnetic radiation-based spectroscopic techniques.

Disclosed here are methods and apparati for making a desired scent, smell, odor, aroma, and/or taste. Also disclosed herein are methods and apparati for making a scent, smell, odor, aroma, and/or taste that will produce a desired response in a desired group of subjects.

Disclosed here are methods and apparati for making a desired scent, smell, odor, aroma, and/or taste. Also disclosed herein are methods and apparati for making a scent, smell, odor, aroma, and/or taste that will produce a desired response in a desired group of subjects.

A volatile organic compound detection device includes a collector comprising: a collector material configured to collect volatile organic compounds given off from a patient's skin; a heater comprising a heating element, the heating element configured to emit a thermal pulse to desorb the volatile organic compounds from the collector material; and a flow channel configured to receive the volatile organic compounds desorbed by the heater; and a fastener configured to secure the collector to the patient's skin.

A volatile organic compound detection device includes a collector comprising: a collector material configured to collect volatile organic compounds given off from a patient's skin; a heater comprising a heating element, the heating element configured to emit a thermal pulse to desorb the volatile organic compounds from the collector material; and a flow channel configured to receive the volatile organic compounds desorbed by the heater; and a fastener configured to secure the collector to the patient's skin.