CN111426715A - Method for measuring perfuming uniformity of cut tobacco based on XPS one-step method - Google Patents
Method for measuring perfuming uniformity of cut tobacco based on XPS one-step method Download PDFInfo
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Abstract
The invention relates to a method for measuring perfuming uniformity of cut tobacco based on an XPS one-step method, and belongs to the technical field of cut tobacco detection. The method comprises four steps of XPS analysis of a flavored cut tobacco sample, data processing, data calculation and flavoring uniformity judgment. The invention does not need to adopt an additional characteristic marker or select a specific component as the characteristic marker for analysis, compared with other gas chromatography-mass spectrometry uniformity methods, the detection time is only about 3-5min, which is superior to 40-50min of the common gas chromatography-mass spectrometry, the detection efficiency is improved by nearly 10 times, and the method is simple and feasible, and is easy to popularize and apply.
Description
Technical Field
The invention belongs to the technical field of cut tobacco detection, and particularly relates to a method for measuring flavoring uniformity of cut tobacco based on an XPS one-step method.
Background
Cigarette formula is always regarded as the core technology of cigarette enterprises, however, the addition of flavors and fragrances in cigarettes is more regarded as a key technology. The cut tobacco making and flavoring process is an indispensable key process in the cut tobacco making production of cigarettes, and the task is to accurately and uniformly apply a certain amount of essence to the blended cut tobacco according to the requirements of production and formula. At present, some enterprises make some attempts on controlling the perfuming uniformity, but mainly deduces and calculates from the theoretical point of view, and no relevant system literature report exists in the industry on the aspect of quantitative characterization of the perfuming uniformity.
However, the chemical composition of the tobacco essence perfume is complex, the varieties are various, and the essence added on the tobacco shreds of the cigarettes is the same in composition, only has different contents, and the content of the added essence is less. When one or more characteristic compounds are used as markers for detecting the perfuming uniformity, the markers are difficult to find, and the markers are difficult to add in large-scale production, so that a reasonable comprehensive detection result cannot be obtained.
X-ray photoelectron spectroscopy (XPS) is an electronic energy spectrum obtained by exciting a sample with soft X-rays and taking photoelectron kinetic energy as a horizontal coordinate and relative intensity as a vertical coordinate. XPS is a quantitative spectroscopy technique that can measure the elemental composition, empirical formula, and the chemical and electronic states of the elements contained therein. The X-ray photoelectron spectrum has the advantages of high sensitivity, simple sample preparation, small destructiveness to samples and the like, and is one of the most effective and widely applied analysis techniques in surface analysis.
Disclosure of Invention
The invention aims to solve the defects of the prior art and provides a method for measuring the flavoring uniformity of cut tobacco based on an XPS one-step method.
In order to achieve the purpose, the technical scheme adopted by the invention is as follows:
a method for measuring perfuming uniformity of cut tobacco based on an XPS one-step method comprises the following steps:
step (1), XPS analysis of flavored cut tobacco samples:
taking flavored cut tobacco to perform XPS full spectrum scanning, C (1s) and O (1s) spectrum scanning and metal spectrum scanning;
step (2), data processing:
respectively calculating [ C ] according to the energy spectrum data obtained in the step (1)]/[O]And [ M1]/[M2]The metal content ratio is calculated, and the peak fitting is carried out on C (1s) according to different corresponding binding energies of the chemical states, and [ C-H ] is calculated]、[C-O]And [ C ═ O]The relative content of each chemical state;
wherein M is1And M2Respectively the metal with the largest content and the metal with the second largest content in the flavored cut tobacco;
step (3), data calculation:
CU uniformity coefficient calculation formula:
xithe relative content of a certain component in the ith analysis is shown, and n is the total analysis times of each sample;
respectively adding C of unperfumed tobacco shreds before flavoring]/[O]、[M1]/[M2]、[C-H]、[C-O]And [ C ═ O]Substituting into CU formula, and calculating to obtain CU[C]/[O]、CU[C-H]、CU[C-O]、CUC＝OAnd CU[M1]/[M2](ii) a Then adding fragrance to the cut tobacco with uniformity coefficient CUGeneral assemblyAnd (3) calculating:
CUgeneral assemblyNamely the perfuming uniformity coefficient of the cut tobacco;
and (4) judging the perfuming uniformity: when CUGeneral assemblyIf the fragrance is more than 250 percent, the perfuming is judged to be uniform, otherwise, the perfuming is judged to be non-uniform.
Further, it is preferable that in the step (1), the XPS analysis conditions are such that the apparatus uses a ray excitation source as a monochromated Al target with energy of α Al K X-ray (1486.6eV) as a radiation source and a background vacuum is maintained at 10 degrees-6Pa order of magnitude, recording full spectrum, C (1s), O (1s) and metal energy level spectrum respectively; the scanning step length of the XPS full spectrum is 0.8eV, and the scanning step length of the core energy level spectrum and the valence band spectrum is 0.125 eV.
Further, it is preferable that the total number of analyses n per sample is not less than 10.
Further, it is preferable that the selected metal spectrum is 2 metal energy spectra with the largest content in the sample tobacco shred, that is, two metal peaks with the largest peak intensity in the whole spectrum.
The analysis conditions used in the present invention must be consistent for the same sample analysis.
CUGeneral assemblyThe larger the value, the better the perfuming uniformity. By the process of the invention, it is also possible to screen the perfuming process, by CUGeneral assemblyThe magnitude of the value is used for screening a better perfuming method.
Compared with the prior art, the invention has the beneficial effects that:
1) the tobacco shred flavoring uniformity detection is based on X-ray photoelectron spectroscopy, adopts a one-step method, does not need to adopt an additional characteristic marker or select a specific component as the characteristic marker for analysis, and is simple and feasible.
2) Compared with other gas chromatography-mass spectrometry analysis uniformity detection methods, the detection time of the method only needs about 3-5min, which is superior to 40-50min of general gas chromatography-mass spectrometry analysis, the detection efficiency is improved by about 10 times, and the method is easy to popularize and apply.
Drawings
Figure 1 XPS survey of flavored samples of example tobacco shreds.
Detailed Description
The present invention will be described in further detail with reference to examples.
It will be appreciated by those skilled in the art that the following examples are illustrative of the invention only and should not be taken as limiting the scope of the invention. The examples do not specify particular techniques or conditions, and are performed according to the techniques or conditions described in the literature in the art or according to the product specifications. The materials or equipment used are not indicated by manufacturers, and all are conventional products available by purchase.
Example 1
A method for measuring perfuming uniformity of cut tobacco based on an XPS one-step method comprises the following steps:
step (1), XPS analysis of flavored cut tobacco samples:
taking flavored cut tobacco to perform XPS full spectrum scanning, C (1s) and O (1s) spectrum scanning and metal spectrum scanning;
step (2), data processing:
respectively calculating [ C ] according to the energy spectrum data obtained in the step (1)]/[O]And [ M1]/[M2]The metal content ratio is calculated, and the peak fitting is carried out on C (1s) according to different corresponding binding energies of the chemical states, and [ C-H ] is calculated]、[C-O]And [ C ═ O]The relative content of each chemical state;
wherein M is1And M2Respectively the metal with the largest content and the metal with the second largest content in the flavored cut tobacco;
step (3), data calculation:
CU uniformity coefficient calculation formula:
xithe relative content of a certain component in the ith analysis is shown, and n is the total analysis times of each sample;
respectively adding C of unperfumed tobacco shreds before flavoring]/[O]、[M1]/[M2]、[C-H]、[C-O]And [ C ═ O]Substituting into CU formula, and calculating to obtain CU[C][O]、CU[C-H]、CU[C-O]、CUC＝OAnd CU[M1][M2](ii) a Then adding fragrance to the cut tobacco with uniformity coefficient CUGeneral assemblyAnd (3) calculating:
CUgeneral assemblyNamely the perfuming uniformity coefficient of the cut tobacco;
and (4) judging the perfuming uniformity: when CUGeneral assemblyIf the fragrance is more than 250 percent, the perfuming is judged to be uniform, otherwise, the perfuming is judged to be non-uniform.
Example 2
A method for measuring perfuming uniformity of cut tobacco based on an XPS one-step method comprises the following steps:
step (1), XPS analysis of flavored cut tobacco samples:
taking flavored cut tobacco to perform XPS full spectrum scanning, C (1s) and O (1s) spectrum scanning and metal spectrum scanning;
step (2), data processing:
respectively calculating [ C ] according to the energy spectrum data obtained in the step (1)]/[O]And [ M1]/[M2]The metal content ratio is calculated, and the peak fitting is carried out on C (1s) according to different corresponding binding energies of the chemical states, and [ C-H ] is calculated]、[C-O]And [ C ═O]The relative content of each chemical state;
wherein M is1And M2Respectively the metal with the largest content and the metal with the second largest content in the flavored cut tobacco;
step (3), data calculation:
CU uniformity coefficient calculation formula:
xithe relative content of a certain component in the ith analysis is shown, and n is the total analysis times of each sample;
respectively adding C of unperfumed tobacco shreds before flavoring]/[O]、[M1]/[M2]、[C-H]、[C-O]And [ C ═ O]Substituting into CU formula, and calculating to obtain CU[C]/[O]、CU[C-H]、CU[C-O]、CUC＝OAnd CU[M1]/[M2](ii) a Then adding fragrance to the cut tobacco with uniformity coefficient CUGeneral assemblyAnd (3) calculating:
CUgeneral assemblyNamely the perfuming uniformity coefficient of the cut tobacco;
and (4) judging the perfuming uniformity: when CUGeneral assemblyIf the fragrance is more than 250 percent, the perfuming is judged to be uniform, otherwise, the perfuming is judged to be non-uniform.
In the step (1), XPS analysis conditions are that during experiment, a ray excitation source is adopted by an instrument as a monochromatized Al target, the energy of the ray excitation source is α Al K X-ray (1486.6eV) as a radiation source, and background vacuum is kept at 10 DEG-6Pa order of magnitude, recording full spectrum, C (1s), O (1s) and metal energy level spectrum respectively; XPS full spectrum scanning step length is 0.8eV, and core energy level spectrumThe scanning step of the valence band spectrum is 0.125 eV.
The total number of analyses n per sample was not less than 10.
The selected metal spectrum is 2 metal energy spectrums with the maximum content in the sample tobacco shred, namely two metal peaks with the maximum peak intensity in the whole spectrum.
Application example 1
A method for measuring perfuming uniformity of cut tobacco based on an XPS one-step method comprises the following steps:
step (1), XPS analysis of flavored cut tobacco samples
Taking 10 parts of brand A flavored cut tobacco, and carrying out XPS full spectrum scanning, C (1s) and O (1s) spectrum scanning and Cu 2p and Cd 2p spectrum scanning.
Step (2) and data processing
And (2) respectively calculating the content ratio of metals [ C ]/[ O ] and [ Cu ]/[ Cd ] according to the energy spectrum data obtained in the step (1), carrying out peak-splitting fitting on C (1s) according to different chemical state corresponding binding energies, and calculating the relative content of each chemical state of [ C-H ], [ C-O ] and [ C ═ O ].
Step (3) data calculation
CU uniformity coefficient calculation formula:
xithe relative content of a certain component in the ith analysis is shown, and n is the total analysis times of each sample;
respectively adding the flavoring tobacco shreds]/[O]、[Cu]/[Cd]、[C-H]、[C-O]And [ C ═ O]Substituting into CU formula, and calculating to obtain CU[C]/[O]`、CU[C-H]、CU[C-O]、CU[C＝O]And CU[Cu]/[Cd]. The results are shown in Table 1;
TABLE 1
Substituting:
The flavoring uniformity coefficient of the obtained cut tobacco is 278.5 percent and more than 250 percent, and the flavoring uniformity is judged.
Application example 2
The same unperfumed cut tobacco of brand A and essence and fragrance as in application example 1 were used to add fragrance evenly by hand. The analysis method is the same as the above (the obtained data are shown in table 1), the perfuming uniformity coefficient of the manually uniformly perfumed cut tobacco is calculated to be 303.5% and more than 250%, and the perfuming uniformity is judged.
Application example 2 was judged to be more evenly perfumed since 278.5% < 303.5%.
The method can effectively distinguish two groups of samples with different perfuming uniformity, quantifies the perfuming uniformity through the perfuming uniformity coefficient, and has popularization and application values.
The foregoing shows and describes the general principles, essential features, and advantages of the invention. It will be understood by those skilled in the art that the present invention is not limited to the embodiments described above, which are described in the specification and illustrated only to illustrate the principle of the present invention, but that various changes and modifications may be made therein without departing from the spirit and scope of the present invention, which fall within the scope of the invention as claimed. The scope of the invention is defined by the appended claims and equivalents thereof.
Claims (4)
1. A method for measuring perfuming uniformity of cut tobacco based on an XPS one-step method is characterized by comprising the following steps:
step (1), XPS analysis of flavored cut tobacco samples:
taking flavored cut tobacco to perform XPS full spectrum scanning, C (1s) and O (1s) spectrum scanning and metal spectrum scanning;
step (2), data processing:
respectively calculating [ C ] according to the energy spectrum data obtained in the step (1)]/[O]And [ M1]/[M2]The metal content ratio is calculated, and the peak fitting is carried out on C (1s) according to different corresponding binding energies of the chemical states, and [ C-H ] is calculated]、[C-O]And [ C ═ O]The relative content of each chemical state;
wherein M is1And M2Respectively the metal with the largest content and the metal with the second largest content in the flavored cut tobacco;
step (3), data calculation:
CU uniformity coefficient calculation formula:
xithe relative content of a certain component in the ith analysis is shown, and n is the total analysis times of each sample;
respectively adding C of unperfumed tobacco shreds before flavoring]/[O]、[M1]/[M2]、[C-H]、[C-O]And [ C ═ O]Substituting into CU formula, and calculating to obtain CU[C]/[O]、CU[C-H]、CU[C-O]、CUC＝OAnd CU[M1]/[M2](ii) a Then adding fragrance to the cut tobacco with uniformity coefficient CUGeneral assemblyAnd (3) calculating:
CUgeneral assemblyNamely the perfuming uniformity coefficient of the cut tobacco;
and (4) judging the perfuming uniformity: when CUGeneral assemblyIf the fragrance is more than 250 percent, the perfuming is judged to be uniform, otherwise, the perfuming is judged to be non-uniform.
2. The method for measuring perfuming uniformity of cut tobacco based on XPS one-step method according to claim 1, wherein in step (1), XPS analysis conditions are that the instrument adopts ray excitation source as monochromated Al target with energy of α Al K X-ray (1486.6eV) as radiation source during experiment, and background vacuum is kept at 10%-6Pa order of magnitude, recording full spectrum, C (1s), O (1s) and metal energy level spectrum respectively; the scanning step length of the XPS full spectrum is 0.8eV, and the scanning step length of the core energy level spectrum and the valence band spectrum is 0.125 eV.
3. The method for measuring perfuming uniformity of cut tobacco based on XPS one-step method according to claim 1, wherein the total number of analysis n of each sample is not less than 10.
4. The method for measuring perfuming uniformity of tobacco shreds based on XPS one-step method of claim 1, wherein the selected metal spectrum is 2 metal energy spectra with maximum content in the tobacco shreds of the sample, namely two metal peaks with maximum peak intensity in the whole spectrum.
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