CN104897449A - Method for configuring human tissue dielectric property simulating material - Google Patents

Abstract

The present invention relates to the technical field of biophysics, in particular to a method for configuring a material for simulating the dielectric properties of human tissue. The method firstly prepares a formula sample, then measures and confirms the dielectric properties of the formula sample, and establishes the dielectric properties and The functional relationship between the formula sample proportion adjustment factors, and finally use the established functional relationship between the dielectric properties with multiple adjustment factors and the formula proportion to solve the simulation of the dielectric properties with any specified conductivity and permittivity Various formula ratios of materials to prepare the designated simulation materials; the present invention uses data fitting technology to quickly calculate and obtain the mixing ratio of various materials in the formula of human tissue dielectric characteristic simulation materials, which can be conveniently and quickly Configure a dielectric property simulation material with any specified conductivity and permittivity.

Description

A configuration method of a material for simulating the dielectric properties of human tissue

technical field

The invention relates to the technical field of biophysics, in particular to a configuration method of a material for simulating the dielectric properties of human tissue.

Background technique

The electromagnetic properties exhibited by matter in the electromagnetic field can be regarded as the inherent properties of matter, and human tissue is no exception. Human tissue exhibits certain electrical and magnetic properties in an electromagnetic field. Electrical properties, sometimes called dielectric properties (EPs), mainly refer to the electrical conductivity and permittivity (also known as dielectric constant) of tissues, and magnetic properties refer to the permeability of tissues. Generally speaking, human tissue is a non-magnetic substance, and its magnetic permeability is close to the magnetic permeability in vacuum, which can be regarded as a constant. The EPs in human tissue are related to the non-uniform distribution of insulating cell membrane and conductive electrolyte in the tissue, so the distribution of EPs in the tissue is non-uniform and frequency-dependent.

It is one of the very important fields of scientific research to study the mechanism and effect of electromagnetic fields and biological tissues. The relevant research results have made great contributions to the cause of human health. For example, the magnetic resonance imaging (MRI) system, which is essentially a system in which strong static magnetic fields, gradient magnetic fields, and radiofrequency magnetic fields interact with human tissue, has now become one of the important large-scale imaging equipment that is essential for clinical disease diagnosis; For example, various electromagnetic physiotherapy equipment, electromagnetic focusing tumor thermal ablation treatment equipment, etc., are essentially interaction systems between different forms of electromagnetic fields and human tissues. In addition, there are still many unsolved problems in the study of the non-thermal effect of the interaction between electromagnetic fields and human tissues, and it is also one of the research hotspots in the field of biophysics. When studying the above-mentioned interaction between the electromagnetic field and human tissue, obtaining the distribution of the electromagnetic field in the tissue is the key research content. One of the methods is to develop artificial materials that can simulate the dielectric properties of human tissue, use such artificial materials to simulate the distribution of human tissue, and then obtain the electromagnetic field distribution in the material through the measurement of electric field and magnetic field.

In the past few decades, many scholars have proposed a variety of tissue dielectric properties simulation materials. In general, these simulated materials are usually in liquid, solid and gel (semi-solid) forms, with gel-like materials being the most popular due to their physical similarity to human tissue and their ability to simulate a wide range of tissue dielectric properties. According to the basic composition, these colloidal simulants can be divided into several categories, and a brief summary of the current related research is listed in Table 1. The storage time of the dielectric material proposed by Chou et al (1984) and Surowiec et al (1992) is very limited, even in a sealed container, it can only be preserved for two weeks; meanwhile, by TX-150, polyethylene powder, aluminum powder, Dielectric materials consisting of water and NaCl (Chou et al 1984), and media materials consisting of TX-151, agar, polyethylene powder, NaCl, and water (Ito et al 2001, Onishi and Uebayashi 2006) cannot simulate Tissues with low water content. Marchal et al (1989) and Sunaga et al (2003) proposed a gelatin-water-based medium material to simulate tissue, but solvent diffusion will occur when two materials with different gelatin concentrations are placed in direct contact, so these materials cannot be fabricated with Long-term stability of heterogeneous phantoms. An oil-gelatin material proposed by Lazebnik et al (2005), Lai et al (2011) and Bakar et al (2011) is capable of simulating the dielectric properties of various biological tissues over a wide frequency range while having long-term stability. However, since this material only uses the volume percentage of oil as an adjustable factor, the changes in relative permittivity and conductivity are interrelated, so this method cannot accurately simulate any specified relative permittivity and conductivity at the same time. Yuan et al (2012) added sodium chloride to the oil-gelatin material, using two adjustable factors, the volume percentage of oil and the concentration of sodium chloride. This makes it possible to simulate different combinations of relative permittivity and conductivity. However, when adjusting either of the two adjustable factors, the volume percentage of oil and the concentration of sodium chloride, the relative permittivity and conductivity will be changed at the same time. As a result, obtaining simulated materials of various human tissues (hundreds of tissue types including various healthy and tumors under different physiological and pathological states) has become an extremely cumbersome work.

To sum up, none of the existing simulation material configuration technologies can directly obtain the proportions of various formulations of the dielectric property simulation materials with any specified conductivity and permittivity. Conductivity and permittivity paired with the dielectric properties of various formulations of simulated materials" ratiometric method.

Contents of the invention

The purpose of the present invention is to provide a configuration method of human tissue dielectric property simulation material in view of the deficiencies of the prior art, using data fitting technology to quickly calculate and obtain the mixing ratio of various materials in the human tissue dielectric property simulation material formula This method can be used to conveniently and quickly configure the dielectric characteristic simulation material with any specified conductivity and permittivity.

The present invention realizes this object through the following technical solutions:

A method for configuring a material for simulating the dielectric properties of human tissue, comprising the following steps:

1) Prepare some formula samples, said formula samples include oil, sodium chloride, gelatin, p-toluic acid, n-propanol, surfactant, deionized water and formaldehyde, said formula samples are prepared according to oil and sodium chloride content from low to high;

2) Measure and confirm the dielectric properties of the formula sample, calculate the average value and relative standard deviation for multiple measurements, and remake and measure the dielectric properties of samples whose relative standard deviation does not meet the requirements;

3) establish the functional relationship between the dielectric properties and the formula sample proportion adjustment factor, the formula proportion adjustment factor is respectively the content of oil and the content of sodium chloride;

4) Using the established functional relationship between the dielectric properties and the formula ratio containing multiple adjustment factors, solve the various formula ratios of the simulated materials with the dielectric properties of the arbitrarily specified conductivity and permittivity, and prepare the specified simulated material.

Wherein, the preparation of the formula sample is carried out according to the following steps:

a. Add 0.1-0.5g of p-toluic acid and 5-15mL of n-propanol into the container, heat to 30-50°C and stir to fully dissolve p-toluic acid;

b. Continue to add 85-95mL of deionized water to the container, and keep the temperature of the deionized water at room temperature;

c. Continue to add 15-20g of gelatin to the container, so that the gelatin is fully soaked in the solution and kept at room temperature;

d. Use a film-type material to seal the container and let it stand at room temperature for 3 to 4 hours;

e. Make some small holes on the film-type material, place the container in a water bath at 65-70°C and heat it for 10-15 minutes;

f. Stir fully until the gelatin is completely dissolved to prepare a gelatin solution, remove surface air bubbles, and cool to 50°C for later use;

g. Heat the oil to 50°C for later use;

h. Add 100-20mL of gelatin solution and 0-80mL of oil into another container in order, and add 0-1.40g of sodium chloride respectively, and keep the temperature of the solution at 50°C;

i. Stir vigorously until all the oil turns into small droplets and disperse in the solution, add 0.5-10mL of surfactant, and stir well until the solution is close to white;

j. Continue to add 10-15mL of formaldehyde solution to the container, continue to stir until uniform, and mix according to the ratio of different oils and gelatin to complete the preparation of the formula sample;

k. Seal the prepared formula sample and place it in a cool place until the formula sample is completely solidified.

Wherein, the formula sample includes several groups, the ratio of oil and gelatin in each group of formula samples is fixed, the content of sodium chloride is matched from low to high, the ratio of oil between each group is matched from low to high, and the ratio of gelatin is changed from low to high. High to low collocation.

As preferably, the content of oil, gelatin and sodium chloride in each formula sample is added according to the following content:

Wherein, the step 2) is specifically: using a coaxial cable with 50 ohm matching impedance as a probe, inserting the probe into the formula sample to be tested, using a network analyzer to measure the network coefficient, and taking the average value of the results of multiple measurements, Using the dielectric property measurement principle of the open-end coaxial probe method, the dielectric properties of the tested formula sample are calculated; the method of measuring the distribution of the dielectric properties of different parts of the sample is used to evaluate the uniformity of the formula sample, and each sample is divided into For different parts, measure different positions on the surface of different parts, measure multiple times at each position, and clean the coaxial probe with a paper towel after measuring each point to prevent the oil on the probe from affecting the results;

Finally, the average value and relative standard deviation are calculated, and the samples whose relative standard deviation does not meet the requirements are remade and the electrical characteristics are remeasured again.

Preferably, the specific step of evaluating the uniformity of the formula sample is: dividing each formula sample into two halves, containing three surfaces, measuring 5 different positions for each surface, and recording 5 measurement data for each position , A total of 75 sets of measurement data were collected from each formula sample; the coaxial probe was fixed at the measurement point for 10-15 minutes before measuring each position;

Finally, the average value and relative standard deviation were calculated, and the samples with relative standard deviation exceeding 5% were recreated and the electrical characteristics were measured.

Wherein, the step 3) is specifically:

With the content of oil and the content of sodium chloride as the adjustment factor of formula content ratio, under the same concentration of sodium chloride, relative dielectric constant is expressed as a first-order polynomial about the volume percentage of oil, and the expression is as follows:

ε'＝m(N)+n(N)O, (1)

Among them, ε' represents the relative dielectric constant, O is the volume percentage of oil (0%-80%), m(N) and n(N) are coefficients about N, N is the concentration of sodium chloride, in each different The relationship between two coefficients m(N) and n(N) and the concentration of sodium chloride is obtained under the concentration of sodium chloride. The coefficient m(N) is expressed by a linear equation about N, while n(N) is expressed by a quadratic Equation, so the relationship between the relative permittivity and the two adjustable factors can be expressed by the following formula:

ε'＝a ₀ +a ₁ N+(a ₂ +a ₃ N+a ₄ N ² )O. (2)

Among them, a ₀ to a ₄ are equation coefficients;

Under the same oil volume percentage, the conductivity is expressed as a first-order polynomial with respect to the concentration of NaCl as follows:

σ＝f(O)+g(O)N, (3)

Among them, σ represents the relative permittivity (S/m), N is the concentration of NaCl, f(O) and g(O) are the coefficients about O, O is the volume percentage of oil, in each different oil volume The relationship between a set of f(O) and g(O) coefficients and the oil volume percentage is obtained under the percentage. The coefficient f(O) is expressed by a cubic equation about O, and g(O) is expressed by a quadratic equation, so the conductivity The relationship between the rate and the two adjustable factors can be expressed by the following formula:

σ＝b ₀ +b ₁ O+b ₂ O ² +b ₃ O ³ +(b ₄ +b ₅ O+b ₆ O ² )N. (4)

Among them, b ₀ to b ₆ are equation coefficients;

Among them, the equation coefficients a ₀ to a ₄ and b ₀ to b ₆ can be calculated by using the non-linear least square method data fitting calculation method according to the measured dielectric properties of each formulation sample.

Compared with the prior art, the beneficial effect of the present invention is: the configuration method of the human tissue dielectric characteristic simulation material of the present invention firstly prepares the formula sample, then measures and confirms the dielectric property of the formula sample, and establishes the dielectric property The functional relationship between the properties and the formula sample ratio adjustment factor, and finally use the established functional relationship between the dielectric properties and the formula ratio containing multiple adjustment factors to solve the dielectric properties of any specified conductivity and permittivity. The various formula ratios of the simulated materials are used to prepare the designated simulated materials; the present invention uses data fitting technology to quickly calculate and obtain the mixing ratio of various materials in the formula of the simulated material for the dielectric properties of human tissue, and the method can be used to facilitate Quickly and easily configure dielectric property simulation materials with any specified conductivity and permittivity.

Description of drawings

Fig. 1 is a schematic diagram of the formula ratio of the simulated material of the present invention.

Fig. 2 is a schematic diagram showing the variation of relative permittivity with oil content.

Fig. 3 is a schematic diagram showing the variation of m(N) with the content of sodium chloride.

Fig. 4 is a schematic diagram showing the variation of n(N) with the content of sodium chloride.

Fig. 5 is a schematic diagram showing the variation of electrical conductivity with the content of sodium chloride.

Fig. 6 is a schematic diagram showing the variation of f(O) with oil content.

Fig. 7 is a schematic diagram showing the change of g(O) with the content of oil.

FIG. 8 is a schematic diagram of the measurement of dielectric properties.

In the figure: 1-computer, 2-network analyzer, 3-coaxial cable, 4-recipe sample to be tested.

Detailed ways

The present invention will be described in detail below in conjunction with the accompanying drawings and specific embodiments.

Example.

A method for configuring a material for simulating the dielectric properties of human tissue in this embodiment includes the following steps:

1) prepare some formula samples, described formula sample comprises oil (peanut oil), sodium chloride, gelatin, p-toluic acid, n-propanol, surfactant, deionized water and formaldehyde, described formula sample according to oil and The content of sodium chloride is matched from low to high;

Wherein, the preparation of the formula sample is carried out according to the following steps:

a. Add 0.1-0.5g of p-toluic acid and 5-15mL of n-propanol into the container, heat to 30-50°C and stir to fully dissolve p-toluic acid;

b. Continue to add 85-95mL of deionized water to the container, and keep the temperature of the deionized water at room temperature;

c. Continue to add 15-20g of gelatin to the container, so that the gelatin is fully soaked in the solution and kept at room temperature;

d. Use a film-type material to seal the container and let it stand at room temperature for 3 to 4 hours;

e. Make some small holes on the film-type material, place the container in a water bath at 65-70°C and heat it for 10-15 minutes;

f. Stir fully until the gelatin is completely dissolved to prepare a gelatin solution, remove surface air bubbles, and cool to 50°C for later use;

g. Heat the oil to 50°C for later use;

h. Add 100-20mL of gelatin solution and 0-80mL of oil into another container in order, and add 0-1.40g of sodium chloride respectively, and keep the temperature of the solution at 50°C;

i. Stir vigorously until all the oil turns into small droplets and disperse in the solution, add 0.5-10mL of surfactant, and stir well until the solution is close to white;

j. Continue to add 10-15mL of formaldehyde solution to the container, continue to stir until uniform, and mix according to the ratio of different oils and gelatin to complete the preparation of the formula sample;

k. Seal the prepared formula sample and place it in a cool place until the formula sample is completely solidified.

Wherein, the formula sample includes several groups, the ratio of oil and gelatin in each group of formula samples is fixed, the content of sodium chloride is matched from low to high, the ratio of oil between each group is matched from low to high, and the ratio of gelatin is changed from low to high. From high to low, the content of oil, gelatin and sodium chloride in each formula sample is added according to the following content:

2) Measure and confirm the dielectric properties of the formula sample, calculate the average value and relative standard deviation for multiple measurements, remake and measure the dielectric properties of the formula samples whose relative standard deviation does not meet the requirements:

As shown in Figure 8, utilize the coaxial line 3 to connect the formula sample 4 to be tested with the network analyzer 2, then electrically connect the network analyzer 2 to the computer 1, and use the coaxial line 3 with a matching impedance of 50 ohms as the probe, Insert the probe into the formula sample 4 to be tested, use the network analyzer 2 to measure the network coefficient, take the average value of the results of multiple measurements, and use the dielectric characteristic measurement principle of the open-end coaxial probe method to calculate the dielectric properties of the formula sample to be tested. properties; the uniformity of the formulation sample is assessed by measuring the distribution of the dielectric properties of different parts of the sample, each sample is divided into different parts, different positions are measured on the surface of different parts, and multiple measurements are taken at each position, and After measuring each point, clean the coaxial line 3 probe with a paper towel to prevent the oil on the probe from affecting the results;

Finally, the average value and relative standard deviation are calculated, and the samples whose relative standard deviation does not meet the requirements are remade and the dielectric properties are remeasured again.

Preferably, the specific step of evaluating the uniformity of the formula sample is: dividing each formula sample into two halves, containing three surfaces, measuring 5 different positions for each surface, and recording 5 measurement data for each position , A total of 75 sets of measurement data were collected from each formula sample; the coaxial line 3 probe was fixed at the measurement point for 10-15 minutes before measuring each position;

Finally, the average value and relative standard deviation were calculated, and the samples with relative standard deviation exceeding 5% were recreated and the electrical characteristics were measured.

3) Establish the functional relationship between the dielectric properties and the formula sample scale adjustment factor:

With the content of oil and the content of sodium chloride as the adjustment factor of formula content ratio, under the same concentration of sodium chloride, relative dielectric constant is expressed as a first-order polynomial about the volume percentage of oil, and the expression is as follows:

ε'＝m(N)+n(N)O, (1)

Among them, ε' represents the relative dielectric constant, O is the volume percentage of oil (0%-80%), m(N) and n(N) are coefficients about N, N is the concentration of sodium chloride, in each different The relationship between two coefficients m(N) and n(N) and the concentration of sodium chloride is obtained under the concentration of sodium chloride. The coefficient m(N) is expressed by a linear equation about N, while n(N) is expressed by a quadratic Equation, so the relationship between the relative permittivity and the two adjustable factors can be expressed by the following formula:

ε'＝a ₀ +a ₁ N+(a ₂ +a ₃ N+a ₄ N ² )O. (2)

Among them, a ₀ to a ₄ are equation coefficients;

Under the same oil volume percentage, the conductivity is expressed as a first-order polynomial with respect to the concentration of NaCl as follows:

σ＝f(O)+g(O)N, (3)

Among them, σ represents the relative permittivity (S/m), N is the concentration of NaCl, f(O) and g(O) are the coefficients about O, O is the volume percentage of oil, in each different oil volume The relationship between a set of f(O) and g(O) coefficients and the oil volume percentage is obtained under the percentage. The coefficient f(O) is expressed by a cubic equation about O, and g(O) is expressed by a quadratic equation, so the conductivity The relationship between the rate and the two adjustable factors can be expressed by the following formula:

σ＝b ₀ +b ₁ O+b ₂ O ² +b ₃ O ³ +(b ₄ +b ₅ O+b ₆ O ² )N. (4)

Among them, b ₀ to b ₆ are equation coefficients;

Wherein, relative dielectric constant is as shown in Figure 2 with the content change relation of oil, m (N) is shown in Figure 3 with the content change relation of sodium chloride, and n (N) is with the content change relation of sodium chloride as Fig. As shown in Figure 4, the relationship between conductivity and the content of sodium chloride is shown in Figure 5, the relationship between f (O) and the content of oil is shown in Figure 6, and the relationship between g (O) and the content of oil is shown in Figure 7. Show.

Among them, the coefficients a ₀ to a ₄ and b ₀ to b ₆ of the equation can be calculated by the nonlinear least squares method according to the measured data of the formula samples obtained: according to the dielectric properties of each formula sample obtained by measurement, the non-linear least squares Using the multiplication data fitting calculation method, the values of the coefficients of each equation are obtained as follows:

a ₀ =63.63[63.30,64.95];

a ₁ =9.899[8.26,11.53];

a ₂ =-64.22[-67.26,-61.17];

a ₃ =-0.06711[-8.54,8.41];

a ₄ ＝-3.041[-9.01,2.93].

b ₀ =0.1315[0.084,0.179]; 10

b ₁ =-0.7346[-1.225,-0.244];

b ₂ =2.667[1.245,4.088];

b ₃ =-2.399[-3.545,-1.252];

b ₄ =0.9264[0.873,0.980];

b ₅ =0.6479[0.254,1.042];

b ₆ =-1.741[-2.344,-1.139].

4) Utilize the functional relationship between the dielectric properties and formula ratios that contain multiple adjustment factors to set up, solve the various formula ratios of the simulated materials of the dielectric properties of any specified conductivity and permittivity collocation, the present invention The formula ratio of the simulated material is shown in Figure 1, and the designated simulated material can be prepared conveniently and quickly according to various formula ratios.

The above-mentioned embodiments only express some implementations of the present invention, and the descriptions thereof are more specific and detailed, but should not be construed as limiting the patent scope of the present invention. It should be pointed out that those skilled in the art can make several modifications and improvements without departing from the concept of the present invention, and these all belong to the protection scope of the present invention. Therefore, the protection scope of the patent for the present invention should be based on the appended claims.

Claims (8)

1. A configuration method of a human tissue dielectric property simulation material, characterized in that, comprising the following steps: 1) Prepare some formula samples, said formula samples include oil, sodium chloride, gelatin, p-toluic acid, n-propanol, surfactant, deionized water and formaldehyde, said formula samples are prepared according to oil and sodium chloride content from low to high; 2) Measure and confirm the dielectric properties of the formula sample, calculate the average value and relative standard deviation for multiple measurements, and remake and measure the dielectric properties of samples whose relative standard deviation does not meet the requirements; 3) establish the functional relationship between the dielectric properties and the formula sample proportion adjustment factor, the formula proportion adjustment factor is respectively the content of oil and the content of sodium chloride; 4) Using the established functional relationship between the dielectric properties and the formula ratio containing multiple adjustment factors, solve the various formula ratios of the simulated materials with the dielectric properties of the arbitrarily specified conductivity and permittivity, and prepare the specified simulated material. 2. the configuration method of human tissue dielectric property simulation material according to claim 1, is characterized in that, the preparation of described formula sample is carried out according to the following steps: a. Add 0.1-0.5g of p-toluic acid and 5-15mL of n-propanol into the container, heat to 30-50°C and stir to fully dissolve p-toluic acid; b. Continue to add 85-95mL of deionized water to the container, and keep the temperature of the deionized water at room temperature; c. Continue to add 15-20g of gelatin to the container, so that the gelatin is fully soaked in the solution and kept at room temperature; d. Use a film-type material to seal the container and let it stand at room temperature for 3 to 4 hours; e. Make some small holes on the film-type material, place the container in a water bath at 65-70°C and heat it for 10-15 minutes; f. Stir fully until the gelatin is completely dissolved to prepare a gelatin solution, remove surface air bubbles, and cool to 50°C for later use; g. Heat the oil to 50°C for later use; h. Add 100-20mL of gelatin solution and 0-80mL of oil into another container in order, and add 0-1.40g of sodium chloride respectively, and keep the temperature of the solution at 50°C; i. Stir vigorously until all the oil turns into small droplets and disperse in the solution, add 0.5-10mL of surfactant, and stir well until the solution is close to white; j. Continue to add 10-15mL of formaldehyde solution to the container, continue to stir until uniform, and mix according to the ratio of different oils and gelatin to complete the preparation of the formula sample; k. Seal the prepared formula sample and place it in a cool place until the formula sample is completely solidified. 3. the configuration method of human tissue dielectric property simulation material according to claim 2, is characterized in that, described formula sample comprises several groups, the ratio of the oil of every group of formula sample and gelatin is fixed, and the content of sodium chloride is by Matching from low to high, the proportion of oil among the groups is matched from low to high, and the proportion of gelatin is matched from high to low. 4. the configuration method of human tissue dielectric property simulation material according to claim 3, is characterized in that, the content of oil, gelatin and sodium chloride in each formula sample is added according to following content: 5. The configuration method of human tissue dielectric property simulation material according to claim 1, characterized in that, said step 2) is specifically: adopting a coaxial line with a matching impedance of 50 ohms as a probe, and inserting the probe into the probe to be tested In the formula sample, use the network analyzer to measure the network coefficient, take the average value of the results of multiple measurements, and use the dielectric property measurement principle of the open-end coaxial probe method to calculate the dielectric properties of the tested formula sample; use different parts of the measurement sample The method of distribution of dielectric properties to evaluate the uniformity of formula samples, each sample is divided into different parts, different positions are measured on the surface of different parts, and multiple measurements are made at each position, and after each point is measured, use Clean the coaxial probe with a paper towel to prevent the oil on the probe from affecting the results; Finally, the average value and relative standard deviation are calculated, and the samples whose relative standard deviation does not meet the requirements are remade and the electrical characteristics are remeasured again. 6. The configuration method of human tissue dielectric property simulation material according to claim 5, characterized in that, the specific step of evaluating the uniformity of the formula sample is: dividing each formula sample into two halves, containing three Surface, measure 5 different positions for each surface, record 5 measurement data for each position, and collect 75 sets of measurement data from each formula sample; before measuring each position, the coaxial probe is fixed at the measurement point for 10-15 minutes ; Finally, the average value and relative standard deviation were calculated, and the samples with relative standard deviation exceeding 5% were recreated and the electrical characteristics were measured. 7. the configuration method of human tissue dielectric property simulation material according to claim 1, is characterized in that, described step 3) is specifically: With the content of oil and the content of sodium chloride as the adjustment factor of formula content ratio, under the same concentration of sodium chloride, relative dielectric constant is expressed as a first-order polynomial about the volume percentage of oil, and the expression is as follows: ε'＝m(N)+n(N)O, (1) Among them, ε' represents the relative dielectric constant, O is the volume percentage of oil, m(N) and n(N) are the coefficients about N, N is the concentration of sodium chloride, obtained at each different concentration of sodium chloride A set of two coefficients m(N) and n(N) are related to the concentration of sodium chloride. The coefficient m(N) is expressed by a linear equation about N, while n(N) is expressed by a quadratic equation, so the relative dielectric The relationship between the constant and the two adjustable factors can be expressed by the following formula: ε'＝a ₀ +a ₁ N+(a ₂ +a ₃ N+a ₄ N ² )O. (2) Among them, a ₀ to a ₄ are equation coefficients; Under the same oil volume percentage, the conductivity is expressed as a first-order polynomial with respect to the concentration of NaCl as follows: σ＝f(O)+g(O)N, (3) Among them, σ represents the relative permittivity (S/m), N is the concentration of NaCl, f(O) and g(O) are the coefficients about O, O is the volume percentage of oil, in each different oil volume The relationship between a set of f(O) and g(O) coefficients and the oil volume percentage is obtained under the percentage. The coefficient f(O) is expressed by a cubic equation about O, and g(O) is expressed by a quadratic equation, so the conductivity The relationship between the rate and the two adjustable factors can be expressed by the following formula: σ＝b ₀ +b ₁ O+b ₂ O ² +b ₃ O ³ +(b ₄ +b ₅ O+b ₆ O ² )N. (4) where b ₀ to b ₆ are equation coefficients. 8. The configuration method of human tissue dielectric property simulation material according to claim 7, characterized in that, the equation coefficients a ₀ to a ₄ , b ₀ to b ₆ can be obtained according to the measured dielectric properties of each formula sample The characteristics are calculated and obtained by using the nonlinear least squares data fitting calculation method.