CN110068398B - Measuring device and method for photo-thermal temperature rise of noble metal nanoparticle solution - Google Patents
Measuring device and method for photo-thermal temperature rise of noble metal nanoparticle solution Download PDFInfo
- Publication number
- CN110068398B CN110068398B CN201910378269.6A CN201910378269A CN110068398B CN 110068398 B CN110068398 B CN 110068398B CN 201910378269 A CN201910378269 A CN 201910378269A CN 110068398 B CN110068398 B CN 110068398B
- Authority
- CN
- China
- Prior art keywords
- refractive index
- temperature
- rainbow
- laser
- noble metal
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
- 238000000034 method Methods 0.000 title claims abstract description 47
- 229910000510 noble metal Inorganic materials 0.000 title claims abstract description 40
- 239000002082 metal nanoparticle Substances 0.000 title claims abstract description 39
- 239000007788 liquid Substances 0.000 claims abstract description 76
- 238000010438 heat treatment Methods 0.000 claims abstract description 46
- 238000001514 detection method Methods 0.000 claims abstract description 30
- 239000002245 particle Substances 0.000 claims abstract description 27
- 238000005259 measurement Methods 0.000 claims abstract description 26
- 238000012545 processing Methods 0.000 claims abstract description 12
- 239000002105 nanoparticle Substances 0.000 claims description 11
- 230000003287 optical effect Effects 0.000 claims description 8
- 239000010970 precious metal Substances 0.000 claims 1
- 230000008859 change Effects 0.000 description 8
- 238000002474 experimental method Methods 0.000 description 8
- 230000008569 process Effects 0.000 description 8
- 238000004458 analytical method Methods 0.000 description 7
- 230000000694 effects Effects 0.000 description 7
- 238000004364 calculation method Methods 0.000 description 6
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 5
- 238000006243 chemical reaction Methods 0.000 description 4
- 230000000630 rising effect Effects 0.000 description 4
- 238000009529 body temperature measurement Methods 0.000 description 3
- 230000007423 decrease Effects 0.000 description 3
- 238000010586 diagram Methods 0.000 description 3
- 238000003384 imaging method Methods 0.000 description 3
- 230000010363 phase shift Effects 0.000 description 3
- 239000000523 sample Substances 0.000 description 3
- 230000003595 spectral effect Effects 0.000 description 3
- 210000005239 tubule Anatomy 0.000 description 3
- 238000010521 absorption reaction Methods 0.000 description 2
- 238000013459 approach Methods 0.000 description 2
- 238000001816 cooling Methods 0.000 description 2
- 238000001704 evaporation Methods 0.000 description 2
- 230000008020 evaporation Effects 0.000 description 2
- 230000017525 heat dissipation Effects 0.000 description 2
- 238000000691 measurement method Methods 0.000 description 2
- 238000000386 microscopy Methods 0.000 description 2
- 238000010951 particle size reduction Methods 0.000 description 2
- 230000000737 periodic effect Effects 0.000 description 2
- 238000011160 research Methods 0.000 description 2
- 239000012798 spherical particle Substances 0.000 description 2
- 238000012360 testing method Methods 0.000 description 2
- 238000013519 translation Methods 0.000 description 2
- 206010028980 Neoplasm Diseases 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 201000011510 cancer Diseases 0.000 description 1
- 238000006555 catalytic reaction Methods 0.000 description 1
- 238000005100 correlation spectroscopy Methods 0.000 description 1
- 230000001419 dependent effect Effects 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 239000012530 fluid Substances 0.000 description 1
- 238000004093 laser heating Methods 0.000 description 1
- 238000012544 monitoring process Methods 0.000 description 1
- 230000009467 reduction Effects 0.000 description 1
- 230000004044 response Effects 0.000 description 1
- 239000004065 semiconductor Substances 0.000 description 1
- 238000004088 simulation Methods 0.000 description 1
- 238000001228 spectrum Methods 0.000 description 1
- 230000000087 stabilizing effect Effects 0.000 description 1
- 238000001931 thermography Methods 0.000 description 1
- 230000036962 time dependent Effects 0.000 description 1
- 230000009466 transformation Effects 0.000 description 1
- 238000012418 validation experiment Methods 0.000 description 1
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01K—MEASURING TEMPERATURE; MEASURING QUANTITY OF HEAT; THERMALLY-SENSITIVE ELEMENTS NOT OTHERWISE PROVIDED FOR
- G01K11/00—Measuring temperature based upon physical or chemical changes not covered by groups G01K3/00, G01K5/00, G01K7/00 or G01K9/00
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
- Y02E30/00—Energy generation of nuclear origin
- Y02E30/30—Nuclear fission reactors
Abstract
The invention provides a measuring device for photo-thermal temperature rise of a noble metal nanoparticle solution, which comprises a controller, a heating laser, a detection laser and linear array CCD (charge coupled device), wherein the heating laser and the detection laser are respectively arranged at two sides of a detected liquid drop, an inclination angle is arranged between the heating laser and the detection laser, the linear array CCD is used for collecting rainbow signals of the detected liquid drop irradiated by laser and transmitting the collected rainbow signals to the controller, and the controller is used for receiving the rainbow signals and processing and analyzing the received rainbow signals to obtain the temperature of the detected liquid drop; the laser rainbow method provided by the invention can simultaneously measure the refractive index and the particle size of the liquid drops, has the non-contact characteristic, and has high measurement precision; meanwhile, the refractive index measured by the rainbow method is an integral reflection of the liquid drop, and the rainbow method can measure the integral average temperature of the liquid drop instead of the local temperature by means of the relation between the refractive index of the liquid and the temperature.
Description
Technical Field
The invention belongs to the technical field of optical measurement, and relates to a measuring device and a measuring method for photo-thermal temperature rise of a noble metal nanoparticle solution.
Background
The laser with specific wavelength irradiates the surface of the noble metal nano-particles to enable the noble metal nano-particles to generate local plasma resonance effect, so that the noble metal nano-particles show strong scattering and absorption enhancement effect on the light with specific wavelength. The absorbed light energy is converted into heat energy through a non-radiative month front process, so that particles generate heat, and the temperature of an environment medium surrounding the noble metal nano particles is further increased, namely photo thermal effect (PT). Based on the photo-thermal effect of the noble metal nano-particles, the photo-thermal effect of the noble metal nano-particles can be applied to the fields of photo-thermal cancer treatment, photo-thermal imaging, photo-thermal catalysis, photo-thermal processing and the like, and the photo-thermal effect of the noble metal nano-particles gradually becomes an important subject in nanotechnology. The research of the photo-thermal efficiency of the noble metal nano particles is an important basis for the application of the noble metal nano particles, and is particularly important for monitoring the photo-thermal temperature rising process of the noble metal nano particle solution in real time and accurately.
In the existing solution temperature technology, the temperature measurement mode of the noble metal nanoparticle solution comprises contact measurement and non-contact measurement, and mainly adopts contact thermocouple temperature measurement, so that the thermocouple is simple to assemble, convenient to replace, high in measurement accuracy, large in measurement range and quick in thermal response time, but the heating process of laser on the nanoparticle solution is usually in an unbalanced temperature rising process, and the temperature is uneven. Meanwhile, the thermocouple is a point temperature detector, and the measured temperature is the temperature near the periphery of the thermocouple probe, not the average temperature or equivalent temperature of the whole body. The thermocouple temperature measurement inevitably brings contact type heat dissipation in the measurement process due to the contact type characteristic. Non-contact measurement is mainly based on optical methods, including differential interference image contrast microscopy, photothermal correlation spectroscopy, photothermal imaging techniques, and the like. The non-contact measurement modes such as differential interference image contrast microscopy and the like avoid contact type heat dissipation, but an experimental system is more complex and the measurement requirement is high.
Disclosure of Invention
The invention aims to solve the technical problems in the prior art, and provides a device and a method for measuring photo-thermal temperature rise of a noble metal nanoparticle solution.
In order to achieve the above purpose, the present invention adopts the following technical scheme:
the invention provides a measuring device for photo-thermal temperature rise of a noble metal nanoparticle solution, which comprises a controller, a heating laser, a detection laser and a linear array CCD device, wherein the heating laser and the detection laser are respectively arranged at two sides of a detected liquid drop, an inclination angle is arranged between the heating laser and the detection laser, the linear array CCD device is used for collecting rainbow signals of the detected liquid drop irradiated by laser and transmitting the collected rainbow signals to the controller, and the controller is used for receiving the rainbow signals and processing and analyzing the received rainbow signals to obtain the temperature of the detected liquid drop.
Preferably, the angle between the heating laser and the detection laser is 10-130 °.
Preferably, two sets of cylindrical mirrors are arranged between the detection laser and the droplet to be detected, each set of cylindrical mirrors comprises two cylindrical mirror bodies, and the detection laser and the cylindrical mirror bodies are coaxially arranged.
Preferably, the controller is also connected with a microscopic camera.
A measurement method for photo-thermal temperature rise of a noble metal nanoparticle solution is based on a measurement device for photo-thermal temperature rise of the noble metal nanoparticle solution, and comprises the following steps:
step 1, utilizing a beam of heating laser and a beam of detection laser to enter through noble metal nano-particle liquid drops from two different directions;
step 2, a high-speed linear array CCD is used for collecting rainbow signals after laser is detected to pass through liquid drops;
step 3, processing and analyzing the collected rainbow signals to obtain the refractive index of the liquid drops;
and 4, obtaining the temperature of the detected liquid drop by utilizing the relation between the temperature and the refractive index.
Preferably, in step 3, the specific method for processing and analyzing the collected rainbow signals is as follows:
rainbow signals are obtained through linear array CCD measurement, and then the position theta of the Airy peak angle is obtained iAirg Through the position theta iAirg Calculating the refractive index n corresponding to the initial temperature 0 ；
The rainbow signal is subjected to fast Fourier transform to obtain the rip frequency f Ripple By the happle frequency f Ripple And calculating the corresponding continuous refractive index n at the non-initial temperature.
Preferably by position theta iAirg The specific method for obtaining the refractive index corresponding to the initial temperature is as follows:
airy peak position θ iAirg Expressed as:
wherein,θ rg is a first order rainbow geometrical optical angle; z i Is a determined set of constants; d is liquidThe diameter of the droplet, lambda is the wavelength of the incident light wave, n 0 Is the refractive index of the droplet particles at the initial temperature.
Preferably by the rip frequency f Ripple The specific method for calculating the corresponding continuous refractive index n at the non-initial temperature is as follows:
first, by the happle frequency f Ripple The expression of (2) is calculated to obtain a happle frequency f at a non-initial temperature Ripple Continuous refractive index n in period 1 Wherein:
ripple frequency f Ripple Is represented by the expression:
f Ripple ＝0.02699n 1 -1.4944 d
wherein n is 1 For a happle frequency f at a non-initial temperature of the droplet particles Ripple A continuous refractive index in the period, d being the diameter of the droplet particles;
secondly, calculating two adjacent happle frequencies f by a CSD method Ripple A phase difference between the two, the phase difference and a happle frequency f at a non-initial temperature Ripple Continuous refractive index n in period 1 And combining to obtain the continuous refractive index n at the non-initial temperature in a continuous time.
Preferably, in step 4, the refractive index n corresponding to the initial temperature obtained in step 3 0 Substituting the continuous refractive index n corresponding to the non-initial temperature into the formula (1) respectively to obtain the initial temperature and the continuous temperature of the measured solution:
t represents the temperature in degrees Celsius; a (T) = 1.3208-1.2325 ×10 -5 T-1.8674×10 -6 T 2 +5.0233×10 -9 T 3 ；B(T)＝5208.2413-0.5179T-2.284×10 -2 T 2 +6.9608×10 -5 T 3 ；C(T)＝-2.5551×10 8 -18341.336T-917.2319T 2 +2.7729T 3 ；D(T)＝9.3495+1.7855×10 -3 T+3.6733×10 -5 T 2 -1.2932×10 -7 T 3 。
Preferably, in step 1, the included angle between the heating laser and the detecting laser light is 10-130 °.
Compared with the prior art, the invention has the following beneficial effects:
according to the measuring device and the measuring method for the photo-thermal temperature rise of the noble metal nanoparticle solution, the measured liquid drops are irradiated through heating lasers and detecting lasers in different directions, rainbow signals of the measured liquid drops are collected through CCD equipment, in first-order laser rainbow intensity distribution, an Airy structure and a high-frequency rib structure overlapped on the Airy structure are arranged, the position of a rainbow angle is obtained through analysis of the Airy structure, and the relation between the refractive index and the diameter of the measured liquid at the initial temperature is obtained according to the position of the rainbow angle; analyzing the happle structure to obtain Airy peak interval, and obtaining a happle frequency f at non-initial temperature in a period of time according to the Airy peak interval Ripple The relation between the refractive index and the diameter of the measured liquid drop in the period; meanwhile, the Airy peak spacing and the cross spectral density analysis method are combined, so that the relation between the continuous refractive index and the diameter of the measured liquid drop at the non-initial temperature in a period of time is obtained; and then the temperature of the detected liquid drop is obtained by combining the relation between the refractive index, the wavelength and the temperature of the liquid; the laser rainbow method provided by the invention can simultaneously measure the refractive index and the particle size of the liquid drops, has the non-contact characteristic, and has high measurement precision; meanwhile, the refractive index measured by the rainbow method is an integral reflection of the liquid drop, and the rainbow method can measure the integral average temperature of the liquid drop instead of the local temperature by means of the relation between the refractive index of the liquid and the temperature.
Meanwhile, the measuring device for the photo-thermal temperature rise of the noble metal nanoparticle solution is simple in experimental device and easy to operate, the whole average temperature of the liquid drops is measured, calculation of photo-thermal conversion efficiency of the noble metal nanoparticle solution is facilitated, meanwhile, the measured liquid drops can be recycled, and nondestructive measurement can be achieved.
Further, the included angle between the heating laser and the detecting laser is 10-130 degrees, so that the rainbow signal of the heating laser is prevented from overlapping with the rainbow signal of the detecting laser.
Furthermore, the beam of the detection laser is adjusted through two groups of cylindrical mirrors, one group of the beam is widened transversely, and the other group of the beam is compressed longitudinally, so that the transverse size of the beam is enough to irradiate the diameter area of the whole liquid drop, the obtained first-order rainbow is large in width, and energy cannot be dispersed.
In conclusion, the method can be used for non-contact and nondestructive measurement of the photo-thermal temperature rising process of the noble metal nano particles, and is simple in experimental operation.
The technical scheme of the invention is further described in detail through the drawings and the embodiments.
Drawings
FIG. 1 is a schematic diagram of a measuring device of the present invention;
the device comprises a controller (1), a controller (2), a heating laser (3), a detection laser (4), a linear array CCD (charge coupled device) device (5), a microscopic camera (6) and detected liquid drops;
FIG. 2 is a schematic diagram of the geometrical paths of reflection and refraction of light at the surface of a droplet, wherein 7, the first light 8, the second light;
FIG. 3 is an intensity distribution of a first order rainbow of spherical particles modeled by Lorentz-Mie theory;
fig. 4 is a spherical drop first order rainbow (d=1 nm);
fig. 5 is a spherical drop first order rainbow (d=2 nm);
fig. 6 is a plot of the first order rainbow intensity angular distribution phase difference of droplets versus refractive index (diameter d=2.6 mm);
fig. 7 is a plot of drop first order rainbow intensity angular distribution phase difference versus refractive index (diameter d=2 mm);
FIG. 8 is a first order rainbow of Au nanoparticle droplets when unheated;
FIG. 9 is the refractive index versus diameter inversion calculation;
FIG. 10 is a view of a measured drop taken by a microscope camera;
FIG. 11 is a graph of droplet diameter calculated from a photomicrograph;
FIG. 12 is a plot of first order rainbow normalized intensity of droplets collected during laser heating;
FIG. 13 is a first order rainbow normalized intensity profile acquired as the droplets cool;
FIG. 14 Rainbow measurement photothermal temperature rise diagram;
fig. 15 is a graph of the change in droplet size during photothermal process by rainbow method.
Detailed Description
The present invention will be described in further detail with reference to the accompanying drawings.
As shown in fig. 1, the measuring device for photo-thermal temperature rise of a noble metal nanoparticle solution provided by the invention comprises a controller 1, a heating laser 2, a detection laser 3 and a linear array CCD device 4, wherein the heating laser 2 and the detection laser 3 are respectively arranged on two sides of a detected liquid drop 6, an inclination angle is arranged between the heating laser 2 and the detection laser 3, the linear array CCD device is used for collecting rainbow signals of the detected liquid drop 6 irradiated by laser and transmitting the collected rainbow signals to the controller, and the controller is used for receiving the rainbow signals and processing and analyzing the received rainbow signals to obtain the temperature of the detected liquid drop 6.
The included angle between the heating laser 2 and the detecting laser 3 is 10-130 deg..
Two groups of cylindrical mirrors are arranged between the detection laser 3 and the detected liquid drop 6, each group of cylindrical mirrors comprises two cylindrical mirror bodies, and the detection laser 3 and the four cylindrical mirror bodies (a, b, c, d) are coaxially arranged.
The cylindrical mirror bodies a and b horizontally and transversely broaden the circular light spots, wherein the focal length f of the cylindrical mirror body a 1 =25.4mm, cylindrical mirror body b focal length f 2 Spread ratio d of cylindrical mirror bodies a, b =100 mm 1 ＝f 2 /f 1 Approximately equal to 4, the light spot is widened transversely by 4 times; the purpose of using the cylindrical mirror bodies c, d is to compress the light beam longitudinally, the focal length f of the cylindrical mirror body c 3 =100 mm, cylindrical mirror body d focal length f 4 =25.4 mm, which is equivalent to compressing the beam 4 times longitudinally.
A microscopic camera 5 is also included for measuring the particle size of the drop under test.
The detection laser 3 is a He-Ne laser with the wavelength of 632.8nm and the power of 15mW;
the heating laser 2 is a 532nm semiconductor laser, and the model of the heating laser is MGL-III-532nm-300wW.
The laser power of the heating laser is far greater than that of the detection laser, the wavelength of the detection laser can not be near the absorption peak of the noble metal nano-particles, and the structure reduces the contribution of the detection laser to the photo-thermal temperature rise of the noble metal nano-particle solution as much as possible.
The invention provides a measurement method for photo-thermal temperature rise of a noble metal nanoparticle solution, which comprises the following steps:
step 1, utilizing a beam of heating laser and a beam of detection laser to enter through noble metal nano-particle liquid drops from two different directions;
step 2, acquiring detection laser through liquid drops by using a high-speed linear array CCD to obtain a first-order rainbow Airy peak position theta iAiry ：
Wherein,θ rg for first order rainbow geometrical optical angle, z i Is a set of constants determined, where i=1, 2,3 …; z 1 ＝1.08728，z 2 = 3.46687; d is the diameter of the droplet particles, lambda is the wavelength of the incident light wave, n 0 Is the refractive index of the droplet particles at the initial temperature.
Step 3, processing and analyzing the collected rainbow signals to obtain the refractive index of the detected liquid drops;
the rainbow signal is subjected to fast Fourier transform to obtain the rip frequency f Ripple By the happle frequency f Ripple The continuous refractive index n corresponding to the non-initial temperature is calculated by the following specific method:
first, by the happle frequency f Ripple The expression of (2) is calculated to obtain a happle frequency f at a non-initial temperature Ripple Continuous refractive index over a periodn 1 Wherein:
f Ripple ＝0.02699n -1.4944 d
wherein n is 1 For a happle frequency f at a non-initial temperature of the droplet particles Ripple A continuous refractive index in the period, d being the diameter of the droplet particles;
secondly, calculating two adjacent happle frequencies f by a CSD method Ripple A phase difference between the two, the phase difference and a happle frequency f at a non-initial temperature Ripple Continuous refractive index n in period 1 Combining to obtain a continuous refractive index n at a non-initial temperature in a continuous time;
step 4, obtaining the temperature of the detected liquid drop through the relation between the temperature of water and the refractive index;
wherein, the relation between the refractive index of water and the wavelength and the temperature is expressed as follows:
t represents the temperature in degrees Celsius; lambda is the wavelength of the incident light wave;
A(T)＝1.3208-1.2325×10 -5 T-1.8674×10 -6 T 2 +5.0233×10 -9 T 3 ；
B(T)＝5208.2413-0.5179T-2.284×10 -2 T 2 +6.9608×10 -5 T 3 ；
C(T)＝-2.5551×10 8 -18341.336T-917.2319T 2 +2.7729T 3 ；
D(T)＝9.3495+1.7855×10 -3 T+3.6733×10 -5 T 2 -1.2932×10 -7 T 3 ；
example 1
As shown in fig. 2, assuming that a spherical droplet has a radius R and a refractive index n, an outgoing ray as shown by a first ray 7 in fig. 3 is obtained after one internal surface reflection by irradiation with a parallel incident light beam having a wavelength λ; the included angle between the light source and the incident light direction is theta, and geometrical optics researches show that the angle theta is thetaMinimum value theta rg ，θ rg Known as geometric optical rainbow angle. θ rg The size of (2) is related to the refractive index of the droplet. In practice, for a monochromatic plane wave incident on a spherical drop of radius R, the rainbow formed by the outgoing rays after undergoing one internal surface reflection is called first-order rainbow, at θ rg There is a distribution of intensities in the vicinity, which can be represented by a first order rainbow.
FIG. 3 is a graph of a first order rainbow scattering intensity distribution of uniform spherical particles modeled according to Lorentz-Mie theory, modeling computational conditions: d=400 μm, n= 1.3324, λ=632.8 nm.
From fig. 3, there is also a high frequency intensity distribution over the Airy structure, i.e. the risple structure. The Airy structure is formed because parallel rays near the first order rainbow geometry optical angle undergo interference of outgoing rays after one reflection from the inner surface of the drop. The direct reflected light from the particle surface interferes with the outgoing light from the first internal surface, as described above with reference to fig. 1, as with the second light 9 in fig. 2, and a risple distribution is formed.
As can be seen from fig. 3, the first-order rainbow Airy structure is composed of a plurality of peaks with a certain interval, and the laser rainbow method can invert the refractive index and the particle diameter of the spherical liquid drop by using the peak interval between the first Airy peak and the second Airy peak of the first-order rainbow and the frequency of the first-order rainbow Ripple, so as to realize the absolute measurement of the refractive index. According to the Airy theory of the first-order rainbow, the position of the first-order rainbow Airy peak can be expressed as
Wherein θ rg I=1, 2,3 …, z for first order rainbow geometry optical angle i For a determined set of constants, reference is made herein to a first Airy peak and a second Airy peak, z 1 ＝1.08728，z 2 = 3.46687; d is the diameter of the droplet particles, lambda is the wavelength of the incident light wave, and n is the refractive index of the droplet particles; thus, the position of each Airy peak angle of the first-order rainbow is related to the diameter, refractive index, and wavelength of the incident light wave of the droplet particles.
The principle of measuring the refractive index of first-order rainbow liquid drops is based on FIG. 2, and the linear array CCD is used for measuring the intensity of the first-order rainbow near the first-order rainbow angle to obtain the position theta of the Airy peak angle iAirg And inverting to obtain the relation between the refractive index and the particle size of the liquid drop.
Ripple frequency f is obtained by performing a Fast Fourier Transform (FFT) on a rainbow signal Ripple By the happle frequency f Ripple Inversion is carried out to obtain the relation between the refractive index and the particle size of the liquid drops:
f Ripple ＝0.02699n -1.4944 d (10)
the variation of the refractive index of the liquid drop is obtained by analyzing the phase variation of the risple frequency.
The small change in refractive index of droplets of different diameters corresponds to the change in first-order rainbow intensity distribution, which is simulated according to Lorentz-Mie theory as shown in fig. 4 and 5.
FIG. 4 is a partial graph of a first order rainbow intensity distribution with a diameter of 1mm, FIG. 5 is a diameter of 2mm, an incident light wavelength of 632.8nm, and refractive indices of 1.3333 and 1.3334, respectively.
It can be seen from the figure that the refractive index varies slightly by 0.0001, but that the rib structure of the rainbow intensity distribution undergoes a significant translation, which is very sensitive to the refractive index of the droplet.
It can also be seen from fig. 4 that the same refractive index, the variable, the corresponding amount of translation of the hippe structure, is different for different diameter drops, which means that the hippe frequency of the first order rainbow of a drop is also strongly dependent on the diameter of the drop.
For two frame signals with the same frequency, the phase difference between the two frame signals can be obtained by a cross spectral density (Cross spectral density, CSD) method, so that the phase relation between two frame rainbow signals with different refractive indexes under the condition of unchanged droplet diameter can be obtained by analysis by the CSD method.
The CSD method comprises the following specific steps:
for two signals x (t) and y (t) having the same frequency and a certain phase difference, let G (t) =x (t) +jy (t), the function G (t) is used for fourier transformation G xy (f) Representation, then G xy (f) Called the cross-spectral functions of x (t) and y (t). G xy (f) Typically a complex number, can be expressed as
G xy (f)＝C xy (f)+jQ xy (f) (11)
G can also be xy (f) Writing out the form of amplitude and phase
G xy (f)＝|G xy (f)|exp[-jθ xy (f)] (12)
Wherein the amplitude isPhase->At amplitude |G xy (f) Near the peak value, θ xy (f) Is a flat linear distribution. When |G xy (f) I is at frequency f M When the peak value is obtained at the position, the corresponding theta xy (f M ) The value of (2) is the phase difference of the two signals.
In the refractive index relative measurement, in the formula (11), x (t) and y (t) respectively represent rainbow rip signals under different refractive indexes, CSD spectrums of the two rip signals are made to obtain phase differences of the two signals, and the refractive index variation corresponding to the two signals can be obtained by comparing the relation of the phase differences along with the change of the refractive index.
Aiming at the requirement of measuring the refractive index of the liquid drop caused by the tiny temperature change of the liquid drop in the photo-thermal effect of the nanoparticle solution, the phase shift simulation calculation of the Ripple structure is carried out under the condition that the diameter of the liquid drop is fixed but the refractive index is changed within a certain range by using Lorentz-Mie theory.
Let the drop diameter be d=2.6mm, the wavelength lambda=632.8nm of the incident light wave, the refractive index is increased from 1.332 to 1.334, the refractive index increment step is 0.000001, and the signal CSD analysis of the first-order rainbow with the rainbow intensity angle distribution between 137 DEG and 142 DEG is calculated. When the first signal is the first signal, d=2.6mm, n=1.332, and the intensity distribution under the other refractive index parameters are respectively calculated by CSD, so as to obtain the phase difference of the rip signal, and the CSD result is shown in FIG. 6 for the two frames of signals. As can be seen from the figure, the risple phase shift has a periodic law as the refractive index increases. As shown in fig. 6, the refractive index is around 1.33, the phase difference has a periodic variation law with the variation of the refractive index, and the phase difference and the refractive index have a linear variation relationship in one period. For a droplet with a diameter d=2.6 mm, the refractive index period 0.00017. Fig. 7 shows a droplet diameter d=2 mm, a refractive index ranging from 1.332 to 1.334, a droplet rainbow intensity distribution risple structure phase difference, which is similar to d=2.6 mm in distribution rule, but a refractive index period 0.00022. This shows that the period of the phase shift of the risple structure dropped from different diameter fluids varies with the period of the refractive index change. In the experiment, if the CSD phase difference can be resolved by 10 degrees, the refractive index relative measurement accuracy is better than 10 degrees -5 The method has the measurement accuracy of temperature better than 0.1 ℃ compared with the relation (3) of the refractive index and the temperature of water. The relative refractive index measuring method is especially suitable for the situation that the refractive index of liquid drops has tiny change, and can accurately measure the tiny change amount of the refractive index of liquid drops.
Example two
The photo-thermal temperature rising process of the noble metal nano-droplet is measured by the experimental device of fig. 1, and the concentration of the Au nano-particle of the sample is: 2.57X 1010 pieces/cm 3;
first, the method of the present invention was verified, and the laboratory room temperature thermocouple measurement was 20.5 ℃. In the experiment, the size of the liquid drop volume is controlled by a syringe pump, and the diameter of the liquid drop is monitored in an auxiliary way through a microscopic camera 5; the acquisition rate of the linear array CCD device 4 was 300 frames/sec. The distance between the liquid drop and the linear array CCD device 4 is 33.00cm, the width of the acquisition of the linear array CCD device 4 is 14 mu m multiplied by 1024, and the angle range of the acquisition of the linear array CCD device 4 is 2.486 degrees. When the heating laser 2 is not on, the first-order rainbow distribution of the sample droplets is collected, as shown in fig. 8. And (3) carrying out data processing according to the intensity distribution of the first-order rainbow acquired by experiments, carrying out inversion calculation on the refractive index and the particle size of the liquid drop, and after 15 calculation iterations, basically stabilizing the calculation result, as shown in fig. 9. Yielding a refractive index n= 1.33121; particle size d= 2902.9 μm. According to the refractive index model of water, the refractive index n= 1.33120 of water at 20.5 ℃, and the result obtained by rainbow measurement has high consistency with the model result. The liquid drop and the tubule forming the liquid drop are on the same imaging surface, and the diameter of the liquid drop can be measured by comparing the number of pixels occupied by the liquid drop and the tubule. As shown in fig. 10 and 11, the intensity boundaries of the droplet and tubule imaging are clear, and the droplet size shows d= 2901.3 μm as measured by microscopic camera. The inversion results of the refractive index and the particle size of the liquid drop are compared with the results obtained by other auxiliary reference approaches, the consistency is high, the feasibility of measuring the refractive index of the Au nanoparticle solution by the rainbow method is verified, and meanwhile, the reasonable and reliable experimental test system and inversion program are also illustrated.
Collecting photo-thermal heating data of spherical liquid drops containing Au nano-particles:
the concentration of Au nanoparticles is: 2.57×10 10 Individual/cm 3; laboratory room temperature was 21.5 ℃. Other experimental conditions were the same as the validation experiment.
In the experiment, the acquisition frequency is 300 frames/s, after the heating laser 2 is started, first-order rainbow images of 54000 frames are continuously acquired for 3 minutes, after the heating laser 2 is closed, first-order rainbow images of 36000 frames are continuously acquired for 2 minutes, namely, data of 54001-90000 frames are first-order rainbow data of a free cooling process of liquid drops after the heating laser is closed, and the whole experiment lasts for 5 minutes. Fig. 12 is a first order rainbow normalized intensity image of data acquired at t=0s, t=5s, t=10s, and t=20s at a power of 320mW of heating laser. As can be seen from the figure, with the heating laser on, there is a significant shift to the right in the first order rainbow position, i.e. in the direction of the first Airy position. The first order rainbow distribution simulated by fig. 4 and 5 shows that as the drop temperature increases, the refractive index decreases and the angular position of the Airy peak of the first order rainbow decreases, and the experimental results are consistent with theory.
Fig. 13 is a graph showing the intensity distribution of the first-order rainbow collected when the droplet was in a free cooling state after the heating laser of 320mW was turned on for 3 minutes, and the graph shows the normalized intensity of the first-order rainbow immediately after the heating laser was turned off and after 2s, 4s, and 8s, respectively, from top to bottom. As can be seen from the figure, the first order rainbow distribution moves in a large angular direction after the laser is turned off. This shows that as the drop cools, the refractive index increases, so does the angle of the Airy peak angle of the first-order rainbow, which is consistent with experimental and theoretical analysis. Experimental data processing is performed on the photothermal temperature rise and the photothermal conversion efficiency of the Au nanoparticle solution.
Two important parameters are involved in the photothermal conversion efficiency analysis of the Au nanoparticle solution, one is the time-dependent relationship of temperature and steady-state temperature, and the other is the surface area of the droplet (diameter of droplet). According to the analysis theory in the step 3, the laser rainbow method can measure the refractive index and the diameter of the liquid drop at the same time, the first-order rainbow (acquisition rate 300 frames/s) of the liquid drop at different time acquired in the experiment is calculated in an inversion way, and the relationship between the refractive index and the temperature of the liquid drop in the formula (3) is used for obtaining the relationship between the temperature and the size of the liquid drop with time.
The temperature dependence of the laboratory room temperature 21.5℃and the heating laser 532nm power 320mW, calculated by inversion of equations (6) - (10), over time is shown in FIG. 14. As can be seen from the graph, the drop temperature increases with the heating of the heating laser, the temperature rise amplitude of the inversion measurement results decreases after heating for about 60s, then the temperature gradually approaches an approximate equilibrium state, the temperature slightly fluctuates between 32 ℃ and 33 ℃, and the experimental results show that the highest temperature tss=33 ℃ under substantial stability when the light and heat rise, and can be seen as being in a thermal equilibrium state. After 3min (180 s) the heating laser was turned off and the temperature began to drop, 5min (after stopping heating for 2 min) the temperature of the droplet was 23.5 ℃.
Meanwhile, the diameter inversion result of the liquid drop is shown in fig. 15, the diameter of the liquid drop is increased along with the temperature increase of the liquid drop, the diameter is reduced, the surface evaporation of the liquid drop mainly causes the continuous reduction of the particle size under the heating of the liquid drop by laser, and experiments show that the particle size reduction rate of the liquid drop is obviously slowed down after the heating laser is turned off, and the situation that the surface evaporation rate of the liquid drop is reduced after the heating laser is turned off causes the particle size reduction rate to be slowed down can be considered. Since the photo-thermal conversion efficiency of the Au nanoparticle solution needs to be calculated by using the mass of the droplet, the mass of the solution can be calculated by the volume of the droplet during the experiment, and the average value of the particle size of the droplet is 2717 μm.
Claims (10)
1. The measuring device is characterized by comprising a controller (1), a heating laser (2), a detection laser (3) and a linear array CCD (charge coupled device) device (4), wherein the heating laser (2) and the detection laser (3) are respectively arranged on two sides of a detected liquid drop (6), an inclination angle is arranged between the heating laser (2) and the detection laser (3), the linear array CCD device is used for collecting rainbow signals of the detected liquid drop (6) irradiated by laser and transmitting the collected rainbow signals to the controller, and the controller is used for receiving the rainbow signals and processing and analyzing the received rainbow signals to obtain the temperature of the detected liquid drop (6).
2. The measuring device for photo-thermal temperature rise of noble metal nanoparticle solution according to claim 1, wherein the included angle between the heating laser (2) and the detecting laser (3) is 10-130 °.
3. The measuring device for photo-thermal temperature rise of the noble metal nanoparticle solution according to claim 1, wherein two sets of cylindrical mirrors are arranged between the detection laser (3) and the droplet (6) to be measured, each set of cylindrical mirrors comprises two cylindrical mirror bodies, and the detection laser (3) and the cylindrical mirror bodies are coaxially arranged.
4. The measurement device for precious metal nanoparticle solution photothermal temperature rise according to claim 1, wherein the controller is further connected with a microscopic camera (5).
5. A method for measuring the photothermal temperature rise of a noble metal nanoparticle solution, characterized in that the measurement device based on the photothermal temperature rise of the noble metal nanoparticle solution according to any one of claims 1 to 4 comprises the following steps:
step 1, utilizing a beam of heating laser and a beam of detection laser to enter through noble metal nano-particle liquid drops from two different directions;
step 2, a high-speed linear array CCD is used for collecting rainbow signals after laser is detected to pass through liquid drops;
step 3, processing and analyzing the collected rainbow signals to obtain the refractive index of the detected liquid drops;
and 4, obtaining the temperature of the detected liquid drop by utilizing the relation between the temperature and the refractive index.
6. The method for measuring the photo-thermal temperature rise of the noble metal nanoparticle solution according to claim 5, wherein in the step 3, the specific method for processing and analyzing the collected rainbow signals is as follows:
rainbow signals are obtained through linear array CCD measurement, and then the position theta of the Airy peak angle is obtained iAirg Through the position theta iAirg Calculating the refractive index n corresponding to the initial temperature 0 ；
The rainbow signal is subjected to fast Fourier transform to obtain the rip frequency f Ripple By the happle frequency f Ripple And calculating the corresponding continuous refractive index n at the non-initial temperature.
7. The method for measuring photothermal temperature rise of a noble metal nanoparticle solution according to claim 6, wherein the light passing through position θ iAirg The specific method for obtaining the refractive index corresponding to the initial temperature is as follows:
airy peak position θ iAirg Expressed as:
wherein,θ rg is a first order rainbow geometrical optical angle; z i Is a determined set of constants; d is the diameter of the droplet particles, lambda is the wavelength of the incident light wave, n 0 Is the refractive index of the droplet particles at the initial temperature.
8. The method for measuring photothermal temperature increase of a noble metal nanoparticle solution according to claim 6, wherein the frequency f is determined by a rip frequency Ripple The specific method for calculating the corresponding continuous refractive index n at the non-initial temperature is as follows:
first, by the happle frequency f Ripple The expression of (2) is calculated to obtain a happle frequency f at a non-initial temperature Ripple Continuous refractive index n in period 1 Wherein:
ripple frequency f Ripple Is represented by the expression:
f Ripple ＝0.02699n 1 -1.4944 d (2)
wherein n is 1 For a happle frequency f at a non-initial temperature of the droplet particles Ripple A continuous refractive index in the period, d being the diameter of the droplet particles;
secondly, calculating two adjacent happle frequencies f by a CSD method Ripple A phase difference between the two, the phase difference and a happle frequency f at a non-initial temperature Ripple Continuous refractive index n in period 1 And combining to obtain the continuous refractive index n at the non-initial temperature in a continuous time.
9. The method for measuring the photothermal temperature rise of a noble metal nanoparticle solution according to claim 6, wherein the step 4 is a step of obtaining a refractive index n corresponding to the initial temperature obtained in the step 3 0 Substituting the continuous refractive index n corresponding to the non-initial temperature into the formula (1) respectively to obtain the initial temperature and the continuous temperature of the measured solution:
t represents the temperature in degrees Celsius; a (T) = 1.3208-1.2325 ×10 -5 T-1.8674×10 -6 T 2 +5.0233×10 -9 T 3 ；
B(T)＝5208.2413-0.5179T-2.284×10 -2 T 2 +6.9608×10 -5 T 3 ；
C(T)＝-2.5551×10 8 -18341.336T-917.2319T 2 +2.7729T 3 ；
D(T)＝9.3495+1.7855×10 -3 T+3.6733×10 -5 T 2 -1.2932×10 -7 T 3 。
10. The method for measuring the photo-thermal temperature rise of the noble metal nanoparticle solution according to claim 5, wherein the included angle between the heating laser and the detection laser is 10-130 degrees in step 1.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201910378269.6A CN110068398B (en) | 2019-05-08 | 2019-05-08 | Measuring device and method for photo-thermal temperature rise of noble metal nanoparticle solution |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201910378269.6A CN110068398B (en) | 2019-05-08 | 2019-05-08 | Measuring device and method for photo-thermal temperature rise of noble metal nanoparticle solution |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN110068398A CN110068398A (en) | 2019-07-30 |
| CN110068398B true CN110068398B (en) | 2023-11-24 |
Family
ID=67370456
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201910378269.6A Active CN110068398B (en) | 2019-05-08 | 2019-05-08 | Measuring device and method for photo-thermal temperature rise of noble metal nanoparticle solution |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN110068398B (en) |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103698256A (en) * | 2013-12-25 | 2014-04-02 | 浙江大学 | Method and device for on-line measurement of liquid spraying through full-field rainbow |
| WO2014179976A1 (en) * | 2013-05-10 | 2014-11-13 | 浙江大学 | One-dimensional global rainbow measurement apparatus and measurement method |
| CN108414408A (en) * | 2018-03-21 | 2018-08-17 | 浙江大学 | A kind of compact-sized coaxial-type whole audience rainbow drop measurement probe |
| WO2019034821A1 (en) * | 2017-08-16 | 2019-02-21 | Rainbowvision | Equipment for characterising a fog of droplets, application to quality-control and to the detection of frost |
| CN208653650U (en) * | 2018-08-15 | 2019-03-26 | 陕西科技大学 | A kind of device based on rainbow method measurement particulate refractive index |
Family Cites Families (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN210154717U (en) * | 2019-05-08 | 2020-03-17 | 陕西科技大学 | Precious metal nanoparticle solution photothermal heating signal acquisition device |
-
2019
- 2019-05-08 CN CN201910378269.6A patent/CN110068398B/en active Active
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2014179976A1 (en) * | 2013-05-10 | 2014-11-13 | 浙江大学 | One-dimensional global rainbow measurement apparatus and measurement method |
| CN103698256A (en) * | 2013-12-25 | 2014-04-02 | 浙江大学 | Method and device for on-line measurement of liquid spraying through full-field rainbow |
| WO2019034821A1 (en) * | 2017-08-16 | 2019-02-21 | Rainbowvision | Equipment for characterising a fog of droplets, application to quality-control and to the detection of frost |
| CN108414408A (en) * | 2018-03-21 | 2018-08-17 | 浙江大学 | A kind of compact-sized coaxial-type whole audience rainbow drop measurement probe |
| CN208653650U (en) * | 2018-08-15 | 2019-03-26 | 陕西科技大学 | A kind of device based on rainbow method measurement particulate refractive index |
Also Published As
| Publication number | Publication date |
|---|---|
| CN110068398A (en) | 2019-07-30 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US11592391B2 (en) | Photothermal imaging device and system | |
| Zhang et al. | Depth-resolved mid-infrared photothermal imaging of living cells and organisms with submicrometer spatial resolution | |
| Withayachumnankul et al. | T-ray sensing and imaging | |
| Blum et al. | Prediction of photothermal phase signatures from arbitrary plasmonic nanoparticles and experimental verification | |
| Miles et al. | Novel optical techniques for measurements of light extinction, scattering and absorption by single aerosol particles | |
| EP3847453A1 (en) | Enhanced-resolution infrared photoacoustic microscopy and spectroscopy | |
| Onofri et al. | On the optical characterisation of nanoparticle and their aggregates in plasma systems | |
| Burr et al. | Determination of the soot aggregate size distribution from elastic light scattering through Bayesian inference | |
| Bouzin et al. | Photo-activated raster scanning thermal imaging at sub-diffraction resolution | |
| Berto et al. | Quantitative absorption spectroscopy of nano-objects | |
| Wang et al. | Photoacoustic response induced by nanoparticle-mediated photothermal bubbles beyond the thermal expansion for potential theranostics | |
| Zhang et al. | High-power THz to IR emission by femtosecond laser irradiation of random 2D metallic nanostructures | |
| Fomina et al. | Photothermal radiometry methods in materials science and applied chemical research | |
| CN110068398B (en) | Measuring device and method for photo-thermal temperature rise of noble metal nanoparticle solution | |
| Khosroshahi | Study of spatial thermal distribution of gold nanourchins in saline by combined transverse probe beam deflection and beam wavefront sensor: biomedical implications | |
| Chen et al. | Advances in inorganic nanoparticles trapping stiffness measurement: A promising tool for energy and environmental study | |
| Li et al. | In situ cell detection using terahertz near-field microscopy | |
| CN210154717U (en) | Precious metal nanoparticle solution photothermal heating signal acquisition device | |
| Albuquerque et al. | Time resolved thermal lens in edible oils | |
| Müller et al. | Determining the material parameters for the reconstruction of defects in carbon fiber reinforced polymers from data measured by flash thermography | |
| Lima et al. | Photothermal detection of a single gold nanoparticle in water suspension | |
| Rodriguez et al. | Frequency-resolved thermal lensing: An approach for thermal diffusivity measurements in liquid samples | |
| WO2012172524A1 (en) | Method and photothermal apparatus for contactless determination of thermal and optical properties of material | |
| Sel et al. | Detection of carbon nanoparticles in suspension by a photothermal technique | |
| Breitenborn | Terahertz Radiation for the Characterization of Plasmonic Nanoparticles and its Biomedical Applications |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |