Apparatus and method for measuring chlorine ions in concrete

1 . An apparatus for measuring chlorine ions in concrete, the apparatus comprising:

a first optical path system;

a second optical path system,

a spectrometer; and

a central control unit,

wherein the first optical path system comprises:

a femtosecond laser device configured to emit ablative femtosecond laser;

an ablative focusing lens group configured to focus the ablative femtosecond laser to obtain focused ablative femtosecond laser; and

a sample configured to receive the focused ablative femtosecond laser to generate a plasma;

the second optical path system comprises:

a heating light source configured to emit heating laser, wherein the heating light source is wavelength-adjustable nanosecond laser;

a dichroic mirror configured to transmit the heating laser to obtain transmitted heating laser;

a reflecting mirror configured to reflect the transmitted heating laser to obtain reflected heating laser; and

a heating laser focusing lens group configured to: focus the reflected heating laser to obtain focused heating laser, and irradiate the focused heating laser on the plasma to obtain a plasma with enhanced spontaneous emission strength,

wherein the heating laser focusing lens group is further configured to focus spontaneous emission of the plasma with enhanced spontaneous emission strength to obtain focused plasma spontaneous emission,

the reflecting mirror is further configured to reflect the focused plasma spontaneous emission to obtain reflected plasma spontaneous emission,

the dichroic mirror is further configured to reflect the reflected plasma spontaneous emission for a second time to obtain plasma spontaneous emission that is reflected for a second time,

the spectrometer is configured to receive the plasma spontaneous emission that is reflected for a second time to obtain spectral information, and

the central control unit is configured to perform a clustering analysis on the spectral information to obtain content of the chlorine ions, and is specifically configured to: perform the clustering analysis on the spectral information to obtain a spectral intensity of the chlorine ions; and determine the content of the chlorine ions according to a relational expression between the spectral intensity of chlorine ions and the content of chlorine ions, wherein the relational expression between the spectral intensity of chlorine ions and the content of chlorine ions is follows:

I

=

FC

s

⁢

A

⁢

g

k

⁢

e

-

E

k

k

B

⁢

T

U

⁡

(

T

)

,

wherein

I is the spectral intensity of the chlorine ions, F is a system constant, C s is the content of the chlorine ions, A is a transition probability at a corresponding energy level, g k is energy level degeneracy, E k is energy at an energy level, k B is a Boltzmann constant, T is a plasma temperature, and U(T) is a partition function of the chlorine ions at the plasma temperature;

wherein the first optical path system and the second optical path system are configured to perform excitation in a manner in which double beams are obliquely incident at an angle of 45°, so as to balance an area and a power density; and

before content of chlorine ions of a to-be-tested sample is tested, a sample group with known content of chlorine ions is calibrated and measured to establish a composite calibration model of different components; calibration curves are established according to the different components and sampling points; calibration results are recorded in the central control unit; and the central control unit divides the different components according to the calibration results.

2 . The apparatus for measuring chlorine ions in concrete according to claim 1 , further comprising:

a delay controller that is separately connected to the femtosecond laser device, the heating light source, and the spectrometer, and is configured to: provide system time and separately control operation of the femtosecond laser device, the heating light source, and the spectrometer.

3 . A method for measuring chlorine ions in concrete based on the apparatus for measuring chlorine ions in concrete according to claim 1 , wherein the method comprises:

irradiating ablative femtosecond laser on a sample to obtain a plasma;

irradiating heating laser on the plasma to obtain a plasma with enhanced spontaneous emission strength;

obtaining spectral information according to spontaneous emission of the plasma with enhanced spontaneous emission strength; and

performing a clustering analysis on the spectral information to obtain content of the chlorine ions, specifically comprising:

performing the clustering analysis on the spectral information to obtain a spectral intensity of the chlorine ions; and

determining the content of the chlorine ions according to a relational expression between the spectral intensity of the chlorine ions and the content of the chlorine ions;

wherein the relational expression between the spectral intensity of the chlorine ions and the content of the chlorine ions is follows:

I

=

FC

s

⁢

A

⁢

g

k

⁢

e

-

E

k

k

B

⁢

T

U

⁡

(

T

)

,

wherein

I is the spectral intensity of the chlorine ions, F is a system constant, C s is the content of the chlorine ions, A is a transition probability at a corresponding energy level, g k is energy level degeneracy, E k is energy at an energy level, k B is a Boltzmann constant, T is a plasma temperature, and U(T) is a partition function of the chlorine ions at the plasma temperature.

4 . The method for measuring chlorine ions in concrete according to claim 3 , wherein the irradiating ablative femtosecond laser on a sample to obtain a plasma specifically comprises:

focusing, by an ablative focusing lens group, the ablative femtosecond laser emitted by a femtosecond laser device to obtain focused ablative femtosecond laser; and

vertically irradiating the focused ablative femtosecond laser on the sample, to obtain the plasma.

5 . The method for measuring chlorine ions in concrete according to claim 3 , wherein the irradiating heating laser on the plasma to obtain a plasma with enhanced spontaneous emission strength specifically comprises:

transmitting, by a dichroic mirror, the heating laser emitted by a heating light source to obtain transmitted heating laser;

reflecting, by a reflecting mirror, the transmitted heating laser to obtain reflected heating laser;

focusing, by a heating laser focusing lens group, the reflected heating laser to obtain focused heating laser; and

irradiating the heated laser on the plasma at an incident angle of 45°, to obtain the plasma with enhanced spontaneous emission strength.

6 . The method for measuring chlorine ions in concrete according to claim 3 , wherein the obtaining spectral information according to spontaneous emission of the plasma with enhanced spontaneous emission strength specifically comprises:

focusing, by a heating laser focusing lens group, the spontaneous emission of the plasma with enhanced spontaneous emission strength to obtain focused plasma spontaneous emission;

reflecting, by a reflecting mirror, the focused plasma spontaneous emission to obtain reflected plasma spontaneous emission;

reflecting, by a dichroic mirror, the reflected plasma spontaneous emission for a second time to obtain plasma spontaneous emission that is reflected for a second time; and

receiving, by a spectrometer, the plasma spontaneous emission that is reflected for a second time to obtain the spectral information.

7 . The method for measuring chlorine ions in concrete according to claim 3 , wherein the apparatus further comprises:

a delay controller that is separately connected to the femtosecond laser device, the heating light source, and the spectrometer, and is configured to: provide system time and separately control operation of the femtosecond laser device, the heating light source, and the spectrometer.