JPS63500674A - Chemical analysis with controlled sample modulation and detection correlation - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed description of the invention] Chemical analysis technology field with controlled sample modulation and detection correlation The present invention distinguishes between two or more chemical components or classes of chemical components in a gas mixture. More specifically, it relates to a method and apparatus for separating at least two or more components to be distinguished. controllably modulates the properties of one component and then detects the presence of one or more components by means of a suitable detection device. and correlate the detected signal with controlled modulation to generate the same signal. How to distinguish between components by identifying one or more components that should have been determined and equipment. This method and apparatus involves the mixing of gaseous components in a continuous stream of mixture. Identification and differentiation of components in a mixture (individual gases in a mixture cannot be identified by a single detection method) have specific application to (not easily distinguishable).

Background technology゛ Knowing the composition of a continuous flowing gas stream consisting of a mixture of components for various reasons; It has become desirable to know the composition in a rapid manner. Measuring the composition of such a flow Prior art systems typically sample the gas stream and then transfer the sample to a buffer. chromatography.

Such batch systems are time consuming and require a separate system for each component of the stream. It is only as accurate as the sensitivity of the detection method within the system. conventional chromatography – Even if the components of the stream are separated, they can be remixed in a continuous flow of carrier gas. Therefore, it is not effective in the case of continuous flow. Chromatography is Separating and identifying individual components of a stream as it passes through a chromatographic detector If a method were available, it could be a valuable means of identifying components in continuous streams. . The present invention proposes a method and apparatus for achieving such separation and identification.

A series by John B. Phillips, one of the inventors along with other authors. The publication is a chromatographic technique expected to improve the sensitivity of chromatographic methods. It describes how to operate. These papers include the following:

1. Multiplex gas chromatography, John B. Phillips, Analytica ANALY-TICAL CHEMISTRY, Volume 52 No. 4, April 2, 1980, Concentration by pyrolysis for multiplex gas chromatography degree modulation, J.B., Valentin, C.G., Currie and J.B., Phillips. , Journal of High Resolution Chromatography End ROMATOGRAPHY φ COMMUNICATIONS (JOLIRNAL OF HIGHR ES-OLUTION CHROMATOGl? APHY & CHROMAT OGRAPHY Coho UNICA-TlONS), Volume 6, November 1983 3. Measurement of methane in ambient air by multiplex gas chromatography, Jaws ・Earl Valentin, Glenn C. Carl and John B.Philippe Analytical Chemistry, Volume 57, No. 6, May 1985 4. Thermal Modulation Enhanced GC Sensitivity, January 14, 1984.

C&EN, p. 62.

In these papers, the authors used chromatography to improve its sensitivity. Describes the operating techniques.

These improved techniques involve the treatment of at least one substance in the presence of another substance in continuous flow. It is applied in the present invention for the purpose of identifying the salient properties of substances.

According to the invention, continuous streams containing components of at least two substances to be distinguished are connected. The material passes through a further treatment system where at least one property of the material in the stream is determined. modulates the component with respect to other things, and the presence of the component in a manner that corresponds to the modulation of the characteristic. Detect within the system. The characteristics are modulated in a predetermined manner, and the response is made consistent with the modulation. This method identifies components that are susceptible to control modulation in relation to Compare with modulation. In this modulation/detection/correlation method, the sensitivity of the system is The presence of components that are separated and otherwise indistinguishable can be identified.

Disclosure of invention The present invention provides for the identification and at least relative quantification of components of a continuous flow stream of a mixture of components. systems and devices that would enable The present invention aims to reduce the amount of vehicle exhaust gas. Vehicles with specific applications for analysis and operated using fuel containing methanol It is useful in analyzing exhaust gas from both. Prior art analysis methods for such gases The detection of methanol and hydrocarbons in the presence of each other in a gas mixture is Generally, this could not be achieved with the same techniques or methods and was therefore slow and imprecise. here As proposed and described in a modulator that achieves a characteristic of at least one of the continuous flow gas in a detectable manner; to the detector. Then modulation in the modulator and in the detector cross-correlates the response to detect the presence or A correlated signal representing the quantification is produced. The gases in the mixed stream respond unequal to the modulation process. If so, the detector response will vary with the modulation difference and Correlation of responses provides correlated signals that can identify and distinguish between different gases in a mixture. will occur.

It is an object of the present invention to provide a method and method that can be used to identify and distinguish the components of a mixture. It is a device.

A further object of the invention according to said object is to detect one of the substances in a detectable manner. at least one substance in the presence of another substance by a method of modulating the properties of and to identify one substance in the presence of another. A method and apparatus that will enable the detection of responses that can be correlated with modulation.

In accordance with said object, the present invention provides a modulation process for identifying the presence of one substance. physical or chemical modulation of a substance as a means of producing a detector response that can be correlated to intended.

Still other objects and features of the invention are the accompanying drawings and descriptions illustrating preferred embodiments. It will be obvious to those skilled in the art from the specification.

Brief description of the drawing FIG. 1 is a schematic block diagram of methods and elements used in practicing the invention. .

FIG. 2 shows a block diagram of one form of apparatus useful in modulating sample flow in the practice of the present invention. This is a diagram.

FIG. 3 shows a block diagram of an alternative device useful in modulating sample flow in accordance with the present invention. This is a diagram.

FIG. 4 is a block diagram of the method of the present invention as used in the analysis of automobile exhaust gas. It is.

Figure 5 shows that all steps of the method of the invention can be carried out in the analysis of sample materials. 1 is a block diagram of a device that can

FIG. 6 is an explanatory diagram of the output correlation response that may occur when implementing the method of the present invention. be.

BEST MODE FOR CARRYING OUT THE INVENTION The method and apparatus of the present invention provides a method and apparatus for improving the relationship between two or more chemical components or chemical components in a gas mixture. includes a system for distinguishing between classes of In the figures of this application, double lines between blocks are attempts to illustrate the passage of gas mixture streams, while dotted lines indicate operational control or signal channels. The solid lines are the energizing connections. The present invention is shown in the block diagram of FIG. Contains four parts as shown. Represented by sample 10 in FIG. The gas mixture to be analyzed, such as The characteristics of one component or class of components, e.g. gas concentration, can be compared to the characteristics of other components in the sample stream. The modulation is intermittently modulated to a different degree than the modulation. Then one or more of the modulated characteristics passing a gas mixture having the above components from the modulator to the transducer or detector 14; , resulting in the generation of a response whose magnitude varies depending on the concentration of the component in the gas stream.

Figure 1 shows that it can be used as part of flushing, but is not required by the basic law. For this purpose, a phantom line filter 16 is shown between the modulator 12 and the transducer 14.

A signal source 18 is operatively connected to the modulator 12 and directs the operation of the modulator in a predetermined direction. Control by expression or controlled order. The control of the modulator in this manner is based on the characteristics of the gas flow. resulting in a series of changes or modifications in the output response of the transducer 14 or the pair of signals. bring about corresponding changes afterwards. The output response of converter 14 is sent to correlator 20. correlator 20 is operatively interconnected with the signal source 18 to provide a modulation operation or control sequence for the modulator 12. Accept the display. As shown, a representation of the correlation produced by the correlator 20 is displayed with the input signal. and provided to a display or recorder at 22.

According to the invention, the device of FIG. The modulator 12 is controlled in a predetermined manner by the signal source 18 to reduce the amount of gas sample. The characteristics of at least one component can be modulated and the detection response to the modulation can be controlled. produces an output signal that would represent the presence of the component that should have been identified according to the correlation of the answers. The converter response is sent to a correlator 20 along with the signal from the signal source for decoding purposes.

Modulator 12 accomplishes the desired modification or modulation of a particular component or components of the sample stream. and the transducer will be interested in the presence of a particular component or components of the sample stream. will respond with an associated output response. The transducer responds to the concentration of the component passing through it. and its output response is modulated in accordance with the modulation of the sample flow components produced by the modulator. It will be done. The “raw” response signal represents the transducer response to all components in the gas stream. However, as it is, it is not a response to a single element of gas flow. however , when correlating the response signal with the modulating signal, the correlated response depends on the particular design of the modulator. the effect of the modulator on the characteristics of a particular component or components of the sample stream according to the will represent.

The system is calibrated for the component of interest by separate iterations of the process. (The gas mixture to be analyzed is a gas mixture containing one or more specific components at known concentrations.) mixture). The calibration process consists of additional calibration mixtures of known concentrations for each species. Repeat to measure the sample gas mixture concentration by interpolation or similar process. A calibration curve can be generated.

The correlator output signal to the display 22 can be displayed or recorded in various ways, and the can be converted into units of concentration for the components in a gas mixture by

The illustrated filter unit 16 removes or alters chemical components consisting of Eliminating the signal carried by such components that could give rise to a signal in may be useful in mixtures of species when it is desirable to change them. Fi The use of routers increases the specificity or precision of the correlation process in correlator 2o. can occur. Filters are effective in both chemical and physical sense. can take many forms.

Parts description Modulators can take many forms that may be effective in modulating the chemical properties of the components that pass through them. can be taken. It can be:

(a) absorbs, oxidizes, reduces, complexes, or otherwise A short bed of granular solids, which can be removed or modified if (b) Open cladding tube with the same type of ability as before (C) Can induce electrical sparks uncoated tubes; (d) tubes that are transparent to ultraviolet or other radiation that produces chemical changes; (e) certain chemical compounds can be preferentially removed from the fluid gas mixture; other equipment.

2 and 3 illustrate examples of systems having thermal modulators and catalytic modulators. . In FIG. 2, the sample flow passes through a conductive coating 26 into a portion of a chromatographic column 28. It passes through a thermal modulator 24 formed by placing it around.

The thermal sheathing is energized from the power source through switch 32.

Switch 32 is controlled by microprocessor 34 to set the desired characteristics of the sample stream. cause modulation. Similar to the basic system of FIG. 1, gas flow passes through detector 36. and provides the signals from the detector and microprocessor to a correlator 38 to obtain the desired produces a correlated signal of In Figure 3, the sample stream is separated into two parts. One side of the sample stream The detector is connected to the detector through the valve 42 and catalyst tube 44, which collectively function as a modulator. Passed 40. The other portion of the sample flow passes directly to detector 40 through valve 46. do. The catalyst tube 44 continuously modulates the properties of the components passing through it, while the valve Add the relevant time. Valves 42,46 are controlled by microprocessor 48. The sample stream is passed through the detector 40 and discarded according to a defined predetermined scheme. It is a two-way valve that can be operated to Similar to FIGS. 1 and 2, the detector 40 The output response and the control signal of the microprocessor 48 are supplied to a correlator (not shown). to produce the desired correlation signal.

Modulator operation can be a reversible or irreversible process, and irreversible In some cases, modulation can be the destruction or chemical transformation of specific components of the gas stream. Wear.

The modulator can be heated, cooled, intermittent sparked or illuminated, or other The modulation is achieved by interrupting said operation using means. thermal modulation Some examples of vessels are as follows.

(a) a chromatographic adsorbent bed whose activity is enhanced by cooling; (b) an oxidation or reduction catalyst bed whose activity is increased by heating; (C) A chemical complexing agent whose activity is enhanced by cooling.

One or more modulators can be in series, each being the same or different, with different thermal histories. or have a different type.

Possible particulate solids for modulators include calcium chloride and cobalt chloride. It will be done.

The transducer or detector 14 is different from the electrical signal of the hot mixture that does not contain components. Any device capable of providing an electrical signal representative of the components of interest in a gas mixture It can also be a device. In the performance of gas analysis, especially gas chromatographs There are many classes of detectors for use in Can be selected for specific applications. An example is as follows.

(a) FID (Flame Ionization) useful for most organic substances that convert hydrocarbons and carbon into thermal conductivity detector), (b) TCD (thermal conductivity detector), general detector, (c) ECD (electron capture) useful for compounds containing electronegative elements such as atoms (d) Based on the ionization potential of the compound and useful for aromatic compounds. PID (Photoionization Detector).

One or more of these can be used in series or in parallel.

In the signal source 18, electrical signals are generated in a predetermined order and the chemical modulator 1 used to initiate a change in the activity level of 2. This means that the gas mixture produces a chemical change, i.e. a chemical signal, which is then detected by a transducer 14, where it is converted into an electrical signal. Return to issue. The modulator signal can be transmitted to a computer, microprocessor, or tape recorder. Disruptions that can be caused by flashlights, strobes, or mechanical devices similar to rotary switches. This is a continuous pulse. Intermittent pulses are of uniform duration, not necessarily uniform time intervals. does not have. They are cooled by opening and closing the heater; by opening the solenoid valve. By supplying gas; by starting an electric spark; two lamp shutters; the modulator by opening or closing; or other similar device appropriate to the type of modulator. 12 is activated. The order of operation of the modulators is preserved for use in the correlation process. Ru.

The central component of the system converts the modulator signal from the signal source 18 into the signal from the converter 14. a correlator 2o that correlates to yield the desired information, concentration of the component or class of interest; It is. Processes the known order of the detector measurement response signal and the modulator signal to determine its formation. Separate the signal by minute or class from other external signals from the detector. the simplest In some cases, this means that the modulator signal can be detected after appropriate scaling or shaping. It may only involve subtracting from the instrument signal. A more elaborate means is to cross It is a correlation or a Fourier transform. Both are carried by modulated substances It is a mathematical technique that extracts information from the transducer signal noise caused by non-modulating materials.

The correlation process is where the effect of the modulation on the sample material is detected by the detector and the modulation process can produce a positive or negative signal response.

Specific application examples Methanol in vehicle exhaust gas Vehicles powered by a mixture of methanol and gasoline contain both substances in their exhaust gas. There may be unburned residue.

When testing for such emissions, it is desirable to distinguish between the two. this In this case, the sample gas mixture is exhaust gas diluted with air and The component is methanol. The four parts of the invention that implement this distinction are the fourth It is illustrated in block form in the figure. Exhaust gas from the exhaust manifold 50 is passed through the solenoid It passes through the switch 52 and creates -C as an 0FF10N valve for the system. Next The exhaust gas then passes through a short thermal modulator 54 .

This thermal modulator 54 can be in the form of a tube, has a surface heater, and has a hydrocarbon Solid adsorbents, complexing agents or oxidizing catalysts with greater activity towards methanol than Contains a bed of media. Detector 56 in this system is a flame ionization detector. shown. Thermal modulator 54 is connected through switch 6o under the control of microprocessor 62. and is energized by a power source 58. The response signal from the detector 56 and the micropro The control signal from processor 62 is supplied to correlator 64, which produces the desired correlation signal. Ru.

Alcohols, aldehydes, and carboxylic acids in vehicle exhaust gas In addition to the methanol fuel listed in the above bar graph, other alcohols can be used as vehicle fuel or or as fuel additives, and these partial combustion products are It is different from the one from the fee. For example, methanol combustion produces formaldehyde, a toxic May result in the formation of substances.

The arrangement of the invention for the measurement of these types of components using the apparatus of FIG. Modulators 12 suitable for chemical classes such as oxidation catalysts for aldehydes (easily oxidized) : a converter 14 such as FID, TCD; a signal source 18; and a correlator 20.

In addition to these, types suitable for separating chemical classes of interest into individual components A filter in the form of a simple gas chromatography column may be required.

Identification of these classes of components is essential for methanol in vehicle exhaust systems. Slightly higher complexity in the correlation process due to the larger number of individual compounds than in the case of and may require more sophisticated output systems. chromatography The delay effect of components moving to the detector for separation on the column is due to the correlation process in the correlator. Probably an element of Rocess.

methane in the air Methane is the main component of natural gas. Recognition of its concentration in the air is a subsurface gas indication of generation (natural sieve or landfill generation) or indication in industrial distribution systems. Either is important. In this measurement, the main component is air, often Other hydrocarbons (heavier than methane) are present. The invention that performs this measurement The four parts include a thermal modulator 12 (preferably with an oxidation catalyst or adsorbent); Methane is unique among hydrocarbons in its oxidizing and absorbing properties; a converter 14 of a suitable type, such as an ID, TCD; a signal source 18 and a methane system; It consists of a microprocessor similar to that described in the case.

Individual low molecular weight hydrocarbons in the gas mixture may be in the air. In Figure 5 As shown, the parts of the invention are made of capillary quartz chroma coated with conductive paint. Thermal modulator 70 consisting of a short segment of a tography column. FID or TCD detector or transducer 72 (both are valid, each with a specific application); the signal pulses for switching power are transferred from the DC power source 76 to heat. a microprocessor 74 that provides a heater cover in the modulator; and a signal pulse and A correlator that demodulates signals for various hydrocarbons by cross-correlating with a thermal modulator. (probably within a microprocessor).

As with other uses of the invention, the sample flows through the system where it passes through filter 78. , the pump 80, the switching valve 82, the control valve 84, and the pressure gauge 86. Enter vessel 70. The thermal modulator is coupled to detector 72 through column 90.

A calibration gas source 88 is connected to the diverter valve 82 to provide a calibration run through the system. Provided as an alternate input.

Thermal modulator 70, detector 72, and column 90 are connected to thermal barriers 92, 9, respectively. 4.96 to provide maintenance and control of heat within these barriers. child For system purposes, the capacitance surrounding the thermal modulator will be maintained at ambient temperature. , the volume around the column will be maintained at approximately 50°C, and the volume around the detector will be maintained at approximately 50°C. The volume will be maintained at 60-100°C.

volatile chlorinated hydrocarbons Some of the components of chlorinated hydrocarbons are toxic, so reducing their concentrations in the environment is There is great interest in monitoring. A particular application of the invention is the release of this type of steam. This is air monitoring in waste disposal.

For this application, the system consists of metals such as silver, which have an affinity for chlorine atoms. Modulator using force and modulated by temperature pulse generation; can be operated in halogen mode multi-molecule ID-type detectors that can be used; and pulse control and and a microprocessor for demodulation. chemical filter at the input stage or A simple elemental gas chromatography column would be beneficial.

Aromatic hydrocarbons in vehicle exhaust The system operated according to the invention for this measurement measures low molecular weight hydrocarbons. may be simpler than the previous description of the system. Two changes can be made, 1 One is intended to measure benzene only, another also measures higher congeners of benzene. Is Rukoto. The difference between this system and systems for identifying aromatic hydrocarbons is , making aromatic hydrocarbons more specific compared to other hydrocarbons' The use of a PID converter would be possible. In general, all other elements are , would be the same. If the system is to be used only for benzene detection, routers and cross-correlators are further simplified to give shorter initial delays in response. It will be.

Volatile sulfur compounds in air or natural gas Hydrogen sulfide and other organic sulfides in air compounds and thiols are toxic nuisances. It also consists of thiols and sulfides is used as a trace additive in natural gas and liquefied petroleum gas to provide leak warning. used in various combinations. The present invention monitors air concentrations or It can be used to analyze fuel gas for the concentration of compounds. for air sampling In this case, the system implementing the present invention may contain metals such as cadmium for sulfur. modulator based on the affinity of sulfur; a sulfur-specific transducer, possibly a flame photometric detector (E PO); microprocessor that controls and demodulates the modulator, e.g. simple gas chromatography that attempts to separate volatile sulfur compounds; - a chemical filter consisting of a column.

For fuel gas analysis, the detector must be modified due to the complete combustibility of the gas mixture. It will be necessary. Supplemental supply of hydrogen gas to the detector is probably not suitable for either application. It would be necessary.

correlation display or if the filter is a chromatography column, This can be displayed using a conventional gas chromatogram as shown in FIG. chromatograph The difference between a positive signal display and a negative signal display is due to the correlation between the modulation signal and the detection signal. Please note that this includes both For example, if the modulator follows a predetermined control of the modulator, Modulates identifiable properties of sample components by delaying and releasing sample components The modulation is then detectable as a detector response to all components in the sample stream. It is Noh. When correlating the detector response signal with a predetermined control of the modulation process, delays and and emissions are continuous positive and negative (or reverse) that identify the substance or component. A signal can be generated.

The microprocessor also performs calculations such as the BTU content (heating value) of the gas mixture. or for any other desired calculation.

Advantages of the invention The present invention can be obtained from gas chromatography while providing the following advantages: It will give similar analytical information.

In conventional gas chromatography, the sample is combined with a batch or slug of gas. (sometimes by evaporation of liquid at the inlet of the instrument). Next, aspirate the sample. The adhesion is passed through a column where the components of the gas mixture are separated and then passed through the column. are detected individually when they appear at the far end of the In the case of the present invention, the sample gas mixture is manual or automatic operation of valves (or injection of liquid with a syringe) eliminate the need for

For applications that do not require the use of chemical filters, the present invention can respond in a matter of seconds at most. If you give the answer and use the filter, the result can be read at intervals as short as 1 second after the initial delay. taken. Filters only incur an initial delay of a few seconds to a few minutes; longer delays originates from the filter, which is a chromatography column. In contrast, regular gas Chromatographs require the same delay of seconds to minutes after each sample introduction.

The present invention also provides greater sensitivity because the sample is continuous. That is, More information (all samples) can be used to calculate results without overloading the system. used.

It also has the effect of repetitive modulator pulsing, which is commonly used in gas chromatography. - has a similar effect on repeated sampling with increased accuracy over the same time interval and give lower detection limits.

Minimal moving parts: pumps to introduce the sample, valves to switch the calibration mixture, and, in some cases, valves to control the auxiliary gases required by the detector.

Although preferred embodiments of the invention have been disclosed in detail, many modifications will occur to those skilled in the art. as will be clear and that the invention is given the broadest possible interpretation within the terms of the following claims. It should be understood that the present invention is not limited to It is.

Engraving (no changes to the content) Procedural amendment (hogen) December 23, 1986

Claims (22)

[Claims] 1. a significant property of at least one substance in the presence of another substance; in a continuous flow stream containing (one substance and the other substance) are in the same chemical phase), a) at least a portion of said continuous flow stream is characterized by the identification of said at least one substance; Before the continuous flow stream is passed through a modulator that can modulate the properties before said at least one substance with respect to at least said other substance in said part; Modify the following characteristics, b) of said continuous flow stream containing said one substance having said modulated identity properties; passing said portion through a detection device capable of responding to said characteristic to generate a response signal; arises, c) controlling the operation of said modulating device in a predetermined manner, so as to perform said modulating device according to said predetermined control; causing a change in the modulation of the identifying property of at least one substance; d) comparing said generated response signal with said predetermined control of said modulating device; in the flow stream by identifying changes in the response signal that correspond to the control of the position. identify one substance mentioned above in A method for identifying significant properties of at least one substance, characterized in that: 2. two different chemicals in the mixture of at least two substances in said continuous flow stream; In identifying the quality, the modulator detects at least one characteristic of the two substances. and at least one of said in said continuous flow stream. a chemical substance that compares the signal of the detection device with the control of the modulation device; 2. The method of claim 1, wherein the method of claim 1 is identified from a correlation representation of a modification of the detected signal resulting from the detection signal. . 3. a plurality of predetermined substances in said continuous flow stream, said at least one of said continuous flow streams; A portion of the predetermined substance is chromatographed from the modulator in a known manner. Through a chromatography column that can be separated into streams through the column , and the comparison step includes the step of passing the raw material through the detection device. the same response signal at the modulator and the chromatography column. associated with said modulator control compared to said predetermined program controlling known separability. identifying the change in the signal caused by the comparison; and identifying the change caused by the comparison. producing a comparison signal producing a continuous indication of the presence of said predetermined substance in accordance with said signal The method according to claim 1. 4. The output of said modulator is used to convert unwanted signals of said continuous flow stream into said method. Claim 1 further includes a step of passing the method through a pre-treatment device for filtration from another step. The method of Section 1, Section 2 or Section 3. 5. From said comparison step for the calibration of said method by introducing a known substance into said continuous flow stream. 4. The method of claim 1, 2 or 3, comprising the step of generating a response. 6. The modulation device includes one or more modulators controlled according to the predetermined method. A method according to claim 1, 2 or 3. 7. a flame ionization detector, wherein the detector produces the response signal; thermal conductivity detector electronic capture detector and photoionization detector Claim 1, 2 or 3 which is a detector selected from the group comprising: the method of. 8. the modulation device produces the modulation of the properties of the continuous flow stream; thermal modulator catalyst modulator radiation response modulator and a device for destroying components of said continuous stream. The method according to item 1, 2 or 3 of the scope of the request. 9. the control of the modulation device is from a preprogrammed microprocessor device; The method of claim 1, 2 or 3. 10. The continuous flow stream is an internal combustion engine operating with a fuel mixture of methanol and gasoline. car exhaust from the engine, and the two different chemicals mentioned above are methanol. and a hydrocarbon, said modulator controlling said continuous flow stream passing through said modulator. a device for chemically denaturing methanol in the portion of the modulator; control produces a predetermined chemical modification of the methanol present in the modulator, and the detection device produces a response signal according to the chemical modification, and the correlation indication is 3. The method of claim 2, wherein the indicator is an indication of the presence of methanol in the fluid stream. 11. The predetermined method for controlling the modulator includes the two methods that pass through the modulator. said change in said flowing stream being present to cause said one volume change of said substance; 4. The method of claim 1, 2 or 3, wherein the method is a thermal change in the preparation device. 12. the associated flow stream is a stream containing methanol and hydrocarbons; The stream is divided into two streams, the first part containing the methanol chemical modifying material. flow through a modulator, then through a first valve device to said detection device, and a second portion. flows directly to said detection device through a second valve device, said valve device directing said continuous flow stream to said detection device. separately switching said first and second portions to said detection device generating said response signal; 3. The method of claim 2, wherein the method is controlled in the predetermined manner. 13. two different chemicals in a mixture of at least two substances in a continuous flow stream A device for quantifying the existence of a) an apparatus containing at least a portion of said continuous flow stream; b) at least one property of said two different chemicals to the other of said chemicals; modulating the properties of certain components of the containing stream in a manner that achieves relative a modulator operating on a contained flow; c) in said containing stream producing a detection signal representative of the total content of the chemical in said containing stream; a detection device operable and responsive to characteristics of said total containing stream; d) said less of said two different chemicals compared to said other chemicals; both modulate the properties of one and said changes to said two different chemicals. a predetermined method that causes a modulation of the properties of the total containing stream according to the relative effectiveness of the regulating devices; a control device for controlling the modulation device, with the formula: e) comparing the detection signal with the predetermined method of controlling the modulator; identifying a change in the detection signal that corresponds to the control of the two in the mixture. A device for quantifying the presence of different chemicals in A device comprising: 14. The chemical to be quantified is fueled by a mixture of methanol and hydrocarbon fuels. methanol and hydrocarbons in the continuous stream of exhaust gas from an engine with The modulator achieves relative disparity in methanol and hydrocarbons in the continuous stream. said continuous flow device which modulates the characteristics of said exhaust gas in a manner that a detection device responsive to the methanol and the hydrocarbons and other components of the exhaust gas; and the controller dissimilarly controls methanol and hydrocarbons in the continuous stream. a predetermined method that is achieved relative to each other and causes a modulation of the exhaust gas according to the relative effect; 14. The apparatus of claim 13, which is an apparatus for controlling the modulator by the following formula. 15. of the exhaust gas that does not represent the methanol and hydrocarbons in the exhaust gas; The claim includes a filter device between the modulation device and the detection device. Apparatus according to item 14 of the scope of the request. 16. The modulator thermally achieves the portion of the continuous flow to is also a device for producing the effect on the property of a substance. Apparatus of Section 13. 17. the modulator has a catalytic effect on the at least one substance; an apparatus for achieving said change in said characteristic by said controller; Claim 1, further comprising controlling the passage of said continuous stream through said device having a mediating effect. Apparatus in Section 3. 18. The control device and the correlation device are controlled by a microprocessor. The apparatus of claim 13. 19. controlling said passage of said continuous stream through said device having said catalytic effect; and the predetermined control of the modulation device includes a control valve device comprising: 18. The apparatus of claim 17, wherein the apparatus controls: 20. controlling the passage of the calibration gas through the calibration gas source and the device to Claims encompassing an apparatus for establishing the responsiveness of said apparatus to said substance in continuous flow Apparatus according to item 13 within the scope of 21. filters, pumps, switching valves, controls between said continuous flow input and said modulating device; a valve and a pressure gauge; a calibration gas source connected to the switching valve for calibrating the device; a chromatography column between the modulator and the detection device, a chromatography column between the modulator and the detector; a thermal barrier to maintain temperature control between the chromatography column and the detection device; an apparatus, and the control apparatus, the correlation apparatus, and the apparatus for displaying the correlation signal. 14. The apparatus of claim 13, comprising a control panel comprising: 22. Is the modulator a class that includes calcium chloride and cobalt chloride? 14. The apparatus of claim 13, comprising a particulate solid of: