Patent Application: US-68126203-A

Abstract:
a method and apparatus for identifying and differentiating multi - component mixtures and identifying contamination thereof using direct comparison of characteristics of the analyte and characteristics of a standard sample of a known compound . these characteristics were obtained using methods and apparatus of spectrum analysis ensuring the possibility of receiving characteristic optical shapes of samples under comparison , which signatures represent a total set of spectral distributions of intensity values for light subjected to interaction with a sample , and the process of correlation of relative intensity values of light subjected to interaction with a sample at assigned wavelengths . the comparison of different optical shapes through comparing the respective intensity values at the assigned wave - lengths , ensures reliable identification of samples and obtaining information as to contamination or non - contamination , which may be identified afterwards by appropriate analytical methods .

Description:
the present invention can be described by the following non - limiting examples , which examples are given for illustration only and not for limitation . a . light from a wide - band source of optical radiation is divided into spectral components , and / or the assigned sections of monochromatic light with a spectral width of δ i are extracted from this light in the selected range of wavelengths λ i while ensuring the possibility of changing the spectral position of these sections with the assigned pitch δλ i ≧ δ i ,. the extracted monochromatic light is then focused onto a probing beam having a specified geometric shape , and the light is directed onto a sample under analysis ; b . a sample of a known mixture k and a sample of an unknown mixture u , are irradiated , by turns , with monochromatic light at the assigned wave - lengths λ 1 , λ 2 , . . . λ m from the selected spectral range λ i ; c . light falling onto a sample , passing through a sample , or reflected by a sample , and the luminescent light is collected and directed to independent photo - detector devices ; d . the intensity values of the light gathered on the photo detector is measured for each of the extracted wavelengths λ 1 , λ 2 , . . . λ m of the selected spectral range λ i ,. that is , the probing light i 0 , the light passing through a sample or reflected by a sample i t , and the luminescence light of a sample i l , including steps of decomposition of the luminescent light into a variety of spectral sections , and / or sequential extraction of the specified sections of wave - lengths of λ 1 , λ 2 , . . . λ n with a width of δ j , with the assigned pitch of δλ j ≧ δ j , where each section corresponds with the predetermined characteristic wave - length of the light in the selected spectral range λ j , which is gathered and registered by a photo - detector is measured . e . the relative intensity of the gathered light passing through a sample , or reflected by a sample , is defined at each of extracted wave - lengths λ m , and the luminescent light for each of the extracted wave - lengths λ m , λ n for a known mixture and unknown mixture , in accordance with the following expressions : t k ⁡ ( λ m ) = i t k ⁡ ( λ m ) i 0 k ⁡ ( λ m ) ; t u ⁡ ( λ m ) = i t u ⁡ ( λ m ) i 0 u ⁡ ( λ m ) ; l k ⁡ ( λ m , λ n ) = i l k ⁡ ( λ m , λ n ) i 0 k ⁡ ( λ m ) ; l u ⁡ ( λ m , λ n ) = i l u ⁡ ( λ m , λ n ) i 0 u ⁡ ( λ m ) , i t k ( λ m ), i t u ( λ m )— intensity values of passing or reflected light for samples of a known k mixture and an unknown u mixture measured within the specified sections λ 1 , λ 2 , . . . λ m of the extracted range of wave - lengths of incident radiation λ i ; i l k ( λ m , λ n ), i l u ( λ m , λ n )— intensity values of the luminescent irradiated by a sample of a known k mixture and a sample of an unknown u mixture within the specified sections λ 1 , λ 2 , . . . λ n of the extracted range of wave - lengths λ j with light excitation within the specified sections λ 1 , λ 2 , . . . λ m of the extracted range of wave - lengths λ i ; i 0 k ( λ m ), i 0 u ( λ m )— intensity values of incident probing radiation falling on the appropriate samples at the time of performing measurements ; f . the corresponding relative intensity values of the light passing through a sample , or reflected by a sample , on each of extracted wave - lengths λ m , and the luminescent light for each of the extracted wave - lengths λ m , λ n for a known mixture and an unknown mixture are compared , and the compliance between the unknown mixture and the known mixture is defined by the following expression : a = 1 2 × ( 1 m × ∑ m = 1 m ⁢ ⁢ t u ⁡ ( λ m ) t k ⁡ ( λ m ) + 1 m × n × ∑ m = 1 m ⁢ ∑ n = 1 n ⁢ l u ⁡ ( λ m , λ n ) l k ⁡ ( λ m , λ n ) ) ⁢ t k ( λ m ), t u ( λ m )— intensity values of passing or reflected light for samples of a known k mixture and unknown u mixture , normalized for the intensity of incident radiation falling on a sample at the corresponding wave - length ; l k ( λ m , λ n ) l u ( λ m , λ n )— intensity values of the luminescent light irradiated by a sample of a known k mixture and unknown u mixture within the specified sections λ 1 , λ 2 , . . . λ n of the extracted range of wave - lengths λ j with light excitation within the specified sections λ 1 , λ 2 , . . . λ m of the extracted range of wave - lengths λ i , normalized for intensity of incident radiation falling on a sample at the corresponding wavelength ; m , n — a number of extracted sections with the wave - lengths under compared within the selected spectral ranges λ i and λ j , accordingly ; δ — a value of allowable deflections of the compared values for the unknown mixture being identified from the corresponding values for the similar values of a standard sample of a known mixture ; g . the presence or absence of foreign impurities ( contaminants ) in the mixture under study is defined by the following expressions : c t ⁡ ( λ i ) = t u ⁡ ( λ m + 1 ) t k ⁡ ( λ m + 1 ) - t u ⁡ ( λ m ) t k ⁡ ( λ m ) ; c l ⁡ ( λ i , λ j ) = l u ⁡ ( λ m + 1 , λ n + 1 ) l k ⁡ ( λ m + 1 , λ n + 1 ) - l u ⁡ ( λ m , λ n ) l k ⁡ ( λ m , λ n ) ; at the same time , if c t ( λ i )= c l ( λ i , λ j )= 0 ± δ , foreign impurities in the sample being identified are absent , and the conclusion about the presence of unwanted contaminations in the mixture under study may be drawn when there are sections c t ( λ i )& gt ; 0 ± δ , and / or c l ( λ i , λ j )≠ 0 ± δ in the difference spectra . in another embodiment of the present invention , the procedure differs from the procedure of example 1 as follows : the step of comparing an unknown sample with a known one is replaced with the step of comparing their electronic absorption - luminescent signatures ( als ), for which purpose the following steps are to be added : a . calibration samples q are prepared , which calibration samples represent a specially made - up mixture or multi - component solutions of a strictly identical constant compound , the absorption or reflectance spectra , and luminescence spectra of which solution ( mixture ) are overlapped with the corresponding spectra of a known mixture within the selected analytical spectral ranges λ i and λ j , i . e . have nonzero intensity in the specified ranges ; b . a standard sample of a known k mixture and a calibration q sample are - placed into an analytical device ; c . measurements and transformations of measured values for intensity of the light passing through or reflected by standard and calibration samples , and their luminescent light , are performed in accordance with steps a - e of example 1 , while taking into account the step of replacing an unknown u sample with the calibration q sample ; d . an electronic absorption - luminescent signature als k of a standard sample is created as follows : als k =  k e  =  ( t 1 k t 1 q ) ( l 1 , 1 k l 1 , 1 q ) ⋯ ( l 1 , n k l 1 , n q ) ⋯ ⋯ ⋯ ⋯ ( t m k t m q ) ( l m , 1 k l m , 1 q ) ⋯ ( l m , n k l m , n q )  , t k ( λ m ), t q ( λ m )- intensity values of passing or reflected light for a sample of a known k mixture and a sample of a calibration q mixture , normalized for intensity of incident radiation falling on a sample at the corresponding wave - length ; l k ( λ m , λ n ), l q ( λ m , λ n )— intensity values of the luminescent light irradiated by a sample of a known k mixture and a calibration q mixture within the specified sections λ 1 , λ 2 , . . . λ n of the extracted range of wave - lengths λ j with light excitation within the specified sections λ 1 , λ 2 , . . . λ m of the extracted range of wave - lengths λ i , normalized for intensity of incident radiation falling on a sample at the corresponding wave - length ; e . an electronic signature of a standard sample als k is entered into the computer database , and / or is saved on an intermediate medium ; f . steps similar to those in step c of this embodiment are carried out with a sample of an unknown mixture , including the step of replacing a standard sample k with a calibration sample q , which is strictly identical with the calibration sample used when measuring a standard sample , and creating an electronic signature als u of a sample being identified : als u =  u e  =  ( t 1 u t 1 q ) ( l 1 , 1 u l 1 , 1 q ) ⋯ ( l 1 , n u l 1 , n q ) ⋯ ⋯ ⋯ ⋯ ( t m u t m q ) ( l m , 1 u l m , 1 q ) ⋯ ( l m , n u l m , n q )  ; g . comparing electronic signatures of an unknown mixture als u =∥ u e ∥ being tested with similar data for a standard sample of a known mixture als k =∥ k e ∥ by the following expression : at the same time , a conclusion on the identity of the unknown mixture and the certain mixture may be drawn when all cells of the matrix ∥ a als ∥ contain only unit elements ( i . e . a i = a i , j = 1 ± δ ); h . to define the presence or absence of unwanted contaminants for the mixture under study by the following expression :  c als  =  u e  -  k e   k e  , at the same time , a conclusion about the presence of unwanted contaminations in the mixture ∥ c als ∥ under studying may be drawn when in the matrix there are nonzero elements | c i , c i , j |& gt ;|± δ |, the values of which exceed the value of allowable deflections of the values being compared for the unknown mixture being identified , from the corresponding values for the similar values of a standard sample of a known mixture ; this example differs from example 1 as follows : a step is added to measure intensity values of raman scattering of a sample being identified and a standard sample , for which purpose the following steps are to be added : a . samples of an unknown mixture and a known mixture are irradiated , by turns , with a monochromatic line of a narrow - band ( lined ) source of light at one or several selected fixed frequencies v r ; b . the light of raman scattering is gathered onto a photo - detector device ; c . for each of the extracted frequencies v 1 , v 2 , . . . , v p of the selected spectral range , intensity values of the light gathered onto a photo - detector of the line are measured , namely : the exciting light falling on a sample i ex , and the light of raman scattering of a sample i r , including steps of decomposition of the light of raman scattering into a variety of spectral sections , and / or sequential extraction of the specified frequency sections v 1 , v 2 , . . . , v p with a width of δ r , with assigned pitch δv r ≧ δ r , where each section corresponds to the predetermined characteristic frequency of the light in the selected spectral range v r , which is gathered and registered by a photo - detector ; d . the relative intensity of the gathered light of raman scattering at each of the extracted frequencies v 1 , v 2 , . . . , v p for a known and unknown mixtures is defined in accordance with the following expressions : r k ⁡ ( v ex , v p ) = i r k ⁡ ( v ex , v p ) i ex k ; r u ⁡ ( v ex , v p ) = i r u ⁡ ( v ex , v p ) i ex u ; i r k ( v ex , v p ), i r u ( v ex , v p )— intensity of raman scattering irradiated by a sample of a known k mixture and a sample of an unknown u mixture within the specified sections v 1 , v 2 , . . . v p of the extracted frequency range v r with light excitation at one of the selected frequencies v ex ; i ex k , i ex u — intensity of the exciting light falling on corresponding samples at the time of performing measurements ; f . data for an unknown mixture being tested with are compared with similar data for a standard sample of a known mixture by the following expression : a = 1 2 × ( r u ⁡ ( v ex , v p ) r k ⁡ ( v ex , v p ) ) × ⁢ ⁢ ( 1 m × ∑ m = 1 m ⁢ ⁢ t u ⁡ ( λ m ) t k ⁡ ( λ m ) + 1 m × n × ∑ m = 1 m ⁢ ⁢ ∑ n = 1 n ⁢ l u ⁡ ( λ m , λ n ) l k ⁡ ( λ m , λ n ) ) , at the same time , a conclusion on the identity of the unknown mixture and the known mixture may be drawn when a = 1 ± δ ; this method differs from that of example 2 as follows : comparison is performed for electronic signatures containing spectral profiles of absorption , luminescence and raman scattering intensities for an unknown mixture sample ( rals u ) and a standard sample ( rals k ), which are formed by the method of example 3 , resulting in the following step of normalization of raman matrixes in the following way : a . a calibration sample q r is prepared , which calibration sample represents a specially made - up mixture or a multi - component solution of a strictly identical constant compound , the luminescence spectrum of which overlaps with the raman spectrum of the known mixture within the selected analytical spectral ranges ; b . the intensity of raman scattering is measured , and the results are converted similarly to steps b - f of example 2 . the signatures of a standard sample and a sample being identified are formed in accordance with the following expressions :  k r  =  ( r 1 , 1 k l 1 , 1 q r ) ⋯ ( r 1 , p k l 1 , p k ) ⋯ ⋯ ⋯ ( r q , 1 k l q , 1 q r ) ⋯ ( r q , p k l q , p q r )  ∦  u r  =  ( r 1 , 1 u l 1 , 1 q r ) ⋯ ( r 1 , p u l 1 , p k ) ⋯ ⋯ ⋯ ( r q , 1 u l q , 1 q r ) ⋯ ( r q , p u l q , p q r )  , r q , p k , r q , p u — intensity values of raman light scattering , normalized for intensity of the exciting light i ex , for samples of the known k mixture and the unknown u mixture , measured at the frequencies i p with light excitation at the frequency i q ; l q , p q r — the luminescence intensity for a calibration sample q r , normalized for the intensity of the exciting light i ex ; c . the electronic signatures of an unknown mixture ∥ u e ∥ being tested are compared with similar data for a standard sample of a known mixture ∥ k e ∥, including the step of comparing raman matrixes ( rals u , k ), by the following expression :  a rals  = (  u r   k r  ) × (  u e   k e  ) , where the identity of samples is defined by the following attribute : ∥ a rals ∥= 1 ± δ ; the process of this embodiment differs from the processes of examples 1 and 2 as follows : a step is added to dissolve samples of a mixture being identified and a certain standard mixture in appropriate solvents . the most effective realization of the complex analysis system of the present invention is performed by a specialized multifunctional measuring device which is able to perform relative measurements of absorption spectra and luminescence , as well as raman scattering , for samples under comparison in a common analytic cycle . this makes it possible to minimize both systematic and random inaccuracies of measurements , and provides a high degree of reliability . the apparatus of the present invention is illustrated in block diagram in fig3 a . this diagram includes all of the functions of the analytical steps required for the analysis of the present invention . to perform complex measurements of absorption spectra , luminescence and raman scattering , a combined light source is used consisting of continuous and line light sources ls , and a matching device , thereby ensuring the possibility of switching and focusing the light from the required source onto a sample . step a of example 1 is performed by a λ i sm - module in the aggregate with a light source ls and a light - gathering device f 1 ; a samples holder sh performs alternate irradiation of samples ( example 1 , step b ) and measurements of intensity values for the probing light i 0 , the passing light i t , and the luminescent light i l of a standard sample k and an analyzed sample u ( example 1 , step d ), which are performed with different positions of the holder in regard to the analyzing light beam ( fig3 b - d ); gathering the light falling on a sample and passing through it is performed by a light gathering device f 2 to a photo - detector pd 1 , and gathering the luminescent light is performed by a light - gathering device f 3 to a photo - detector pd 2 , at the same time the luminescence light is disintegrated into spectral components , and the required spectral section is extracted from this light by a λ j sm - module ( example 1 , step c ); defining the relative intensities of the passed light and the luminescent light ( example 1 , step e ), which represent experimentally measured intensity values for the passed light i t and the luminescent light i l normalized for i 0 . this is performed while processing signals are measured at different positions of the sample holder sh ( fig3 b - d ), by the devices included in a control and registration module ( r & amp ; rm ), and / or further mathematical treatment implemented by an external computing device ; the comparison of corresponding relative intensities ( example 1 , step f ) is performed similarly to ascertain the identity or difference of samples being analyzed ; the r & amp ; rm module also contains devices to control measurements ensuring switching of sample positions , setting the specified intervals of the extracted wavelengths , and measuring signals with a specified time constant , as well as power units of light sources and photo - detectors ( pmt ) ensuring stabilization and automatic correction of power supply modes , and an interface of communication with an external computing device and / or devices of accumulation , storage and display of information . the algorithm of comparison of characteristics of a known sample and an unknown sample provided in the present invention gives an unambiguous characteristic for the mixture being identified , whether it corresponds with a standard sample or not . inconsistency between a sample being identified and a standard sample is evidence of a difference in their component compounds . the compliance level for a mixture being identified and a standard sample may be characterized by the value of correlation of their absorption - luminescent signatures θ . in the simplest case , this correlation is expressed by the ratio of a number of coincident elements of matrixes n i , j , in accordance with the analytical expressions of the methods by claims 1 - 4 , and the total number of significant elements of matrixes n : as an example of liquids identification , the following liquids are chosen ( table 1 ): two samples of drinking water from different sources ; two samples of food spirit from different manufacturers ; two samples of vodka from different manufacturers ; two samples of motor gasoline of different types ; two samples of shampoo of the same type from different manufacturers . each of the above - listed objects , by turns , is considered as a standard sample and compared by turns with the whole aggregate of tested samples for the compliance level in accordance with the method of examples 1 and 2 . as one can see in table 1 , compliance is not observed for a standard sample and tested ones for all comparisons , with the exception of total identity of samples . at the same time , objects having the same microcompound elements ( water , ethanol , vodka ) have the higher compliance level . it should be noted that ascertaining the identity of samples by comparing their differences , within the framework of the present invention , presents different tasks which differ in the amount of time required . to ascertain unambiguously the identity of objects being compared , it is necessary to determine the compliance by the greatest possible number of parameters , whereas , for ascertaining their difference , it is enough when at least one of the parameters under comparison for a mixture being identified differs from a corresponding parameter for a standard sample . this is illustrated by examples 7 and 8 . in table 2 , a comparison of compliance levels is presented for pure liquids which were obtained from correlating absorption - luminescent signatures ( als ) in accordance with the method shown in examples 1 and 2 , and the same signatures supplemented by the raman co - factor ( rals ) in accordance with the processes of examples 3 and 4 . as can be seen in table 2 , adding the raman component does not substantially change the value of the conformity level for objects related by being in the same chemical class , and results in drastic differences for objects which are in different chemical classes . in fig4 , correlation spectra are shown for intensity values of impurity luminescence using the same fixed excitation wavelength ( 230 nm ) for water taken from various points of the municipal water supply system ( curves 1 - 3 on fig4 ) and for the same water contaminated with municipal wastewater ( curve 4 ); 3 , 4 - benzopyrene ( curve 5 ); and petroleum derivatives ( curve 6 ). as one can see from fig4 , all three samples of clean water have minimal differences , while at the same time the presented samples have perceptible differences using the complete set of parameters ( this value for samples 1 , 2 , and 3 , respectively , are 0 . 86 , 0 . 9 and 0 . 95 ). it is clear that contaminants in the water change the situation drastically , so that users can determine that these are distinct from a standard sample only on the basis of the date presented , which reduces the analysis time by a factor of about 10 - 20 . this example shows identification of a variety of industrial products produced for domestic purposes : three samples of dry yeast , two of which belong to the same production lot of the same manufacturer ( samples 1 - 1 and 1 - 2 ), and a sample of a similar product from another manufacturer ( sample 2 ); three samples of washing powder of the same brand from the same production lot from a well - known manufacturer ( samples 1 - 1 and 1 - 2 ), and a sample of a similar product of another brand from the same manufacturer ( sample 2 ); three samples of domestic gel - like washing liquid of the same brand , from eth same production lot , from a well - known manufacturer ( samples 1 - 1 and 1 - 2 ), and a sample of a similar product from the same manufacturer , but another brand ( sample 2 ); one can distinctly see in table 3 that samples of products manufactured from strictly identical raw materials during the same processing cycle have a high compliance level with each other . this compliance is not observed when the manufacturing conditions are changed . this example illustrates determining the impurities contaminating liquids , in this case , drinking water , with additives of different classes of substances . as a standard sample , clean drinking water was accepted here . the following liquids were tested for the presence of contaminants : the standard water the standard water with priority pah ( 3 , 4 - benzopyrene ) dissolved therein ; the standard water with crude petroleum dissolved therein ; the same water with organophosphorus insecticides dissolved therein : thiophos ( structure 1 ) and foksim ( structure 2 ); the standard water with chlorine dissolved therein . the standard water with medical products dissolved therein : methyl ether of benozylecognine ( structure 3 ); 1 , 3 , 7 - trimethylxanthine ( structure 4 ); penicillin ( structure 5 ); and tetracycline ( structure 6 ); the same water containing e . coli ; the same water contaminated with municipal wastewater . this example demonstrates the adaptability of the method of the present invention in monitoring water systems for the purpose of exposing contamination with either chemical or biological contaminants . as can readily be seen from table 4 , the compliance level of water contaminated with 3 , 4 - benzopyrene with eth standard water was reduced to one half , which compliance was reduced even more when the water was contaminated with petroleum . a similar situation was also observed in the case of contamination with substances such as organophosphorus insecticides , chlorine , medical products , bacteria , and municipal wastewater . it should be noted that adding the chlorine resulted in a drastic reduction of the conformity level of the als signature of a sample being tested with a sample of clean water . at the same time , visual checks of outline maps of these objects ( see fig2 ) do not permit the user to draw the same conclusions . these facts point out the high level of accuracy of the present invention . the foregoing description of the specific embodiments will so fully reveal the general nature of the invention that others can , by applying current knowledge , readily modify and / or adapt for various application such specific embodiments without undue experimentation and without departing from the generic concept . therefore , such adaptations and modifications should and are intended to be comprehended within the meaning and range of equivalents of the disclosed embodiments . it is to be understood that the phraseology or terminology employed herein is for the purpose of description and not of limitation . the means and materials for carrying out various disclosed functions may take a variety of alternative forms without departing from the invention . thus , the expressions “ means to . . . ” and “ means for . . . ” as may be found in the specification above and / or in the claims below , followed by a functional statement , are intended to define and cover whatever structural , physical , chemical , or electrical element or structures which may now or in the future exist for carrying out the recited function , whether or nor precisely equivalent to the embodiment or embodiments disclosed in the specification above . it is intended that such expressions be given their broadest interpretation . 1 . lavrik , n . l . chemistry and life ( magazine ), xxi century , no . 3 , 2000 , as well as http :// www . informauka . ru / rus / 2000 / 2000 - 03 - 06 - 0124_r . htm . 2 . karagodin , g . m . book on vodka and wine - making , cheljabinsk , ural ltd ., 1998 , p . 468 . 3 . dedkov , ju . m . russian chemical magazine , 2002 , v . 46 , no . 4 , pp . 11 - 17 . 4 . korte , f . ecological chemistry . foundation and concepts . m . ; 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