摘要:
A method and analyzer for monitoring the progress of a chemical process in which a fixed volume sample of the reactive mixture of the chemical process is periodically gathered and injected into a fluid stream of a liquid carrier. The sample in the liquid carrier is passed through an infrared detector which detects the amount present in the sample of a species of the reaction mixture which is indicative of the progress of the chemical process.
摘要:
A method and analyzer for monitoring the progress of a chemical process in which a fixed volume sample of the reactive mixture of the chemical process is periodically gathered and injected into a fluid stream of a liquid carrier. The sample in the liquid carrier is passed through an infrared detector which detects the amount present in the sample of a species of the reaction mixture which is indicative of the progress of the chemical process.
摘要:
A method and apparatus for detecting the presence of a vapor of an alkyl ester of phosphoric acid, particularly tributylphosphate, in ambient air. A sample of ambient air is heated to convert any alkyl ester of phosphoric acid to an alkene. The heated sample of air is then passed to a sample loop. Carrier air periodically carries a fixed volume of sample from the sample loop through a chromatographic column to a photoionization detector which detects the presence and amount of the alkene in the sample.
摘要:
Renewable composite microelectrodes for electrochemical applications are formed by an initial coating on an elongated conductive substrate of less than 500 micrometers over at least a portion of its length with a modifier composition, and a superposed coating of electronically resistive polymer. The initial coating is exposed only at the tip portion of the microelectrode. The initial coating may be an absorbed layer of the modifier, a homogeneous layer of a polymeric matrix with the modifier dispersed therein, or a layer of a polymer with a modifier in its chain. The modifier provides distinctive properties to the surface of the electrode which may be electroactivity, inclusion, acidic/basic, complexing/chelating or electrocatalysis. The microelectrode will normally be used with only the tip portion thereof immersed in the solution, and it may be renewed by removing the contaminated tip portion.
摘要:
Renewable modified composite electrodes for electrochemical application are provided by homogeneous structure of a conductive filler disposed in a polymeric matrix or binder containing a modifier in the polymer chain. The modifier provides distinctive characteristics of electroactivity, inclusion, acidic/basic, complexing/chelating or electrocatalysis to the surface of the electrode in a solution. After use, the electrode may be renewed by removing a surface portion and thereby exposing a fresh portion of the homogeneous structure.
摘要:
Provided is a method for regulating the concentration of water in the acid feed stream in a process for the production of HF by the reaction with a fluorine containing material, the method comprising: (a) providing an acid feed stream comprising bound water and free water; (b) estimating the concentration of bound water and free water in the acid feed stream by providing a probe in said feed stream; and (c) adjusting the concentration of free water in said process stream based on said estimating step.
摘要:
An analyzer and method for detecting and measuring the water content in a liquid sample in which the liquid sample is fed from its source to a head space chamber. The flow of liquid to the chamber is then halted, the water molecules in the liquid sample allowed to pass into the gaseous phase and escape from the liquid sample. A water-free carrier gas is caused to flow to the chamber and over the liquid to carry the gaseous water molecules to a moisture detector while the flow of the liquid sample to the head space chamber is halted.
摘要:
A system and method for monitoring a volatile species in a liquid in which liquid is fed from its source to a head space chamber. The flow of liquid to the chamber is then halted, the volatile species allowed to escape into the gaseous phase above the liquid, and a carrier gas is caused to flow to the chamber and over the liquid to carry the gaseous phase of the species to a detector while the flow of the liquid to the head space chamber is halted. The liquid may be under pressure at the point in the source from which it is withdrawn into the system and returned to the source at a point also under pressure.
摘要:
A method for detecting the presence of a vapor of an alkyl ester of phosphoric acid, particularly tributylphosphate, in ambient air. A sample of ambient air is heated to convert any alkyl ester of phosphoric acid to an alkene. The heated sample of air is then passed to a sample loop. Carrier air periodically carries a fixed volume of sample from the sample loop through a chromatographic column to a photoionization detector which detects the presence and amount of the alkene in the sample.
摘要:
Renewable modified composite electrodes for electrochemical applications are provided by homogeneous structures of a conductive filler and a modifier dispersed within a polymer matrix or binder. The modifiers may provide characteristics of electroactivity, inclusion, adsorption or electrocatalysis to the surface of the electrode in a solution. After use, the electrode may be renewed by removing a surface portion and thereby exposing a fresh portion of the homogeneous structure.