In some reservoirs, groundwater or formation water is exposed to high salinity salt solution and high underground temperature conditions. In high salinity environments,traditional fracturing fluid are prone to salt crystallization, salt deposition and colloidal particle aggregation.Moreover, In high temperature environment, additives and colloids in traditional fracturing fluids may degrade, fail or denature, resulting in the degradation of the fracturing fluid performance. Most of the fracturing fluids studied to date cannot meet the performance requirements of temperature and salt resistance simultaneously while ensuring a low cost.To solve this problem,using acrylamide (AM), acrylic acid (AA), 2-acrylamido-2-methylpropanesulfonic acid (AMPS), and the hydrophobic monomer allyl polyethylene glycol (APEG) as molecular skeletons, an associating viscoelastic polymer, p(AM/AA/AMPS/APEG), was prepared via inverse emulsion polymerization. The structure and morphology of the polymer were characterized via Fourier transform infrared spectroscopy, 1H nuclear magnetic resonance spectroscopy, scanning electron microscopy, and laser particle size analysis, and its rheological properties, particularly thixotropy and viscoelasticity, were evaluated. The p(AM/AA/AMPS/APEG) solution showed the characteristics of a viscoelastic fluid, as well as good temperature resistance at 160°C and a concentration of 0.8 wt.%. The viscosity of p(AM/AA/AMPS/APEG) was 64.88 and 56.77 mPa·s after shearing in 20000 mg/L NaCl solution and CaCl2 solution for 1 h at 140°C and 170 s− 1, respectively. With increasing polymer concentration, the intermolecular association efficiency of the hydrophobic groups and the apparent viscosity of the solution increased. The p(AM/AA/AMPS/APEG) polymer exhibited good thixotropy, salt resistance, temperature resistance, and shear resistance. This hydrophobically associating polymer shows good application prospects in the development and utilization of unconventional oil and gas resources.
Research Article
Preparation and rheological properties of a hydrophobically associating viscoelastic polymer with temperature and salt resistance via reversed-phase emulsion polymerization
https://doi.org/10.21203/rs.3.rs-4641661/v1
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Inverse emulsion polymerization
Hydrophobic association
Viscoelasticity
Rheological properties
Salt tolerance
Temperature and shear resistance
Unconventional resources such as shale oil and tight oil are among the most important energy resources in the world[1]. Owing to the low permeability of shale reservoirs, traditional production often requires treatments such as staged large-displacement fracturing of horizontal wells and hydraulic fracturing[2–4]. The development of unconventional oil and gas reservoirs is very different from that of conventional oil and gas reservoirs. In the fracturing of unconventional oil and gas reservoirs, fractures with high permeability and long length are usually required[5–7].As an indispensable technology for the development of oil and gas resources, hydraulic fracturing has made great contributions in the past few decades, especially for unconventional oil and gas resources[8].Polyacrylamide (PAM) is widely used in polymer fracturing systems[9–12].However, in the harsh reservoir environment, the temperature and concentration of mineral salt ions increase sharply, resulting simultaneously in the charge shielding effect and the crosslinking between ions and hydrophobically associating water-soluble polymers.Moreover,acidification occurs under high salinity and high temperature conditions[13–15]. When the temperature exceeds 70°C, the amide group is prone to hydrolysis, resulting in a sharp decrease in polymer viscosity, which will limits the applicability of PAM. To solve these problems, intense research efforts have recently been devoted to improve the salt and temperature resistance of hydrophobically associating polymers in the context of oil and gas field development by introducing functional monomers[16–19].
Cheng et al.[20] used acrylamide (AM), acrylic acid (AA), 2-acrylamide-2-methylpropanesulfonic acid (AMPS), and 2-acrylamide-sodium octadecyl sulfonate (C18MPS) as monomers and ammonia as a neutralizer to prepare a high-concentration emulsion-type multi-effect variable viscosity slippery water thickener via inverse emulsion polymerization. The viscosity of a 0.35 wt.% polymer solution and 0.75 wt.% high viscosity slick water could be maintained above 30 and 65 mPa·s, respectively, after shearing at 100°C for 2h; however, the polymer did not show good temperature resistance. Ma et al.[21] synthesized a ternary hydrophobically associating polymer (PADM) via free radical copolymerization using AM, methacryl oyloxyethyl trimethyl ammonium chloride, and PMB-16 as monomers.The apparent viscosity of a 0.5 wt.% PADM aqueous solution was 43.0 mPa·s at 90°C and a shear rate of 170 s− 1. Meanwhile, at 25°C and a shear rate of 170 s− 1, the apparent viscosity of a 0.5 wt.% PADM aqueous solution in 0.25 wt.% CaCl2 solution and 0.6 wt.% NaCl solution was 37.0 and 34.0 mPa·s, respectively. Zhou Xinchao[22] prepared a hydrophobically associating polyacrylamide thickener by inverse emulsion polymerization using AA, AMPS and octadecyl acrylate as reaction monomers. The viscosity of a 2 wt.% polymer solution reached 171、165, and 140 mPa·s after shearing at 30°C, 60°C and 90°C respectively,for a certain period of time. The final viscosity of 10000mg/L and 20000 mg/L polymer solutions at 180°C was higher than 50 mPa·s, indicating the good temperature and shear resistance of the system. However, solving the problem of the polymer salt resistance, requires adjusting the amount of polymer to maintain the viscosity, which greatly increases the cost.
To solve the above problems and ensure a good rheological behavior in terms of low elasticity and high viscosity, a novel polymer p(AM/AA/AMPS/APEG) with a strong hydrophobically associating network structure in salt solution was prepared via inverse emulsion polymerization using AM, AA, and AMPS as molecular skeletons and the hydrophobic monomer allyl polyethylene glycol (APEG). The structure and morphology of p(AM/AA/AMPS/APEG) were characterized via Fourier transform infrared (FTIR) spectroscopy, 1H nuclear magnetic resonance (NMR) spectroscopy, scanning electron microscopy (SEM), and laser particle size analysis, and its temperature and salt resistance were analyzed.
Reagents and instruments
AM, AA, and AMPS of analytical grade were purchased from Shandong Ruihai Mishan Chemical Co., Ltd. White oil of industrial grade was provided by Zhejiang Zhengxin Petroleum Technology Co., Ltd. Span-60 and Tween-60 of analytical grade were purchased from Jiangsu Anyi Chemical Co., Ltd. The following chemicals were purchased in analytically pure form: tetrahydrofuran from Qianyan Chemical Technology (Wuhan) Co., Ltd., allyl chloride from Shanghai Aladdin Biochemical Technology Co., Ltd., polyethylene oxide from Sigma-Aldrich (Shanghai) Trading Co., Ltd., magnesium sulfate from Shandong Jiuzhong Chemical Co., Ltd., NP-10 from Shanghai Jizhi Biochemical Technology Co., Ltd., ammonium persulfate, sodium bisulfite, acetone, and potassium bromide from Shandong Xuanhai Chemical Co., Ltd., and anhydrous ethanol, anhydrous calcium chloride, sodium hydroxide, and sodium chloride from Tianjin Tianli Chemical Reagent Co., Ltd.
The following instruments were used: BT-9300S laser particle size distribution instrument, Dandong Baite Instrument Co., Ltd.; ZNN-D6 six-speed rotary viscometer, Qingdao Hengtaida Electromechanical Equipment Co., Ltd.; Nicolet Summit FTIR Spectrometer, Semmerfeld Technology (China) Co., Ltd.; Avance Core NMR spectrometer, Bruker, Switzerland; environmental scanning electron microscope SEM5000, Guoyi Quantum Technology (Hefei) Co., Ltd; LGJ-12 vacuum freeze-drying agent, Shanghai Bajiu Industrial Co., Ltd; JBD-3000L nitrogen machine, Sichuan Juliancheng Machinery Co., Ltd; Discovery HR 30 mixed rheometer, TA instruments, USA; XGJ-S digital high-speed mixer, Shanghai Yuezhong Instrument and Equipment Co., Ltd.
Preparation of the hydrophobic monomer APEG
First, (4.0 g, 0.1 mol) NaOH and tetrahydrofuran were added to a 100-mL three-port round-bottom flask and rapidly stirred at 50°C–55°C. Then, 7.6 g of allyl chloride and 40 g of polyethylene oxide were added dropwise to the reaction mixture, followed by stirring at 50°C–55°C for 6 h. The crude product was obtained by drying over magnesium sulfate, and the solvent was distilled after filtration. The residue was purified by column chromatography to obtain a final yield of 93 wt.%. The preparation reaction is as follows:
Synthesis of inverse emulsion polymer p(AM/AA/AMPS/APEG)
240 g of AM, 135 g of AA, 30 g of AMPS, and 6 g of APEG were weighed in a 1000 mL beaker, and 1.5 wt.% ammonium persulfate solution and 300 g of distilled water were added. After stirring to fully dissolve the monomer, the pH was adjusted to 6.5–7.5 with 100 mL of a 45 wt.% NaOH aqueous solution. A mixture of 240 g of white oil and 34 g of emulsifier with a Span-60:Tween-60 mass ratio of 4:1 was thoroughly stirred and mixed with the aqueous phase solution, and a pre-emulsified water-in-oil emulsion was obtained after high-speed stirring. The pre-emulsion was poured into a four-port flask and deoxygenated by passing N2 for 60 min. Then, 1 wt.% sodium bisulfite solution was slowly and uniformly dropped to initiate the free radical polymerization. The reaction proceeded for 3–4 h while controlling the reaction temperature at 38°C–40°C. After cooling, an appropriate amount of phase inversion agent NP-10 was added to obtain a new polymer thickener. The synthetic reaction equation is as follows:.
Structure characterization and performance test
The p(AM/AA/AMPS/APEG) polymer was characterized via FTIR spectroscopy using the KBr pellet method. To prepare the sample, an emulsion of the polymer was repeatedly washed with anhydrous ethanol, filtered, dried, and ground to powder.
The 1H NMR spectra of a purified, dried, and crushed sample of p(AM/AA/AMPS/APEG) were recorded on a AvanceCore NMR spectrometer using deuterium oxide D2O as the solvent.
The particle size was analyzed using a laser particle size analyzer. To this aim, a p(AM/AA/AMPS/APEG) emulsion was ultrasonically dispersed in deionized water.
To observe the microstructure of p(AM/AA/AMPS/APEG) via SEM, a p(AM/AA/AMPS/APEG) powder sample was obtained by washing and drying a polymer emulsion prepared in aqueous solution with a mass fraction of 0.2 wt.%. After freezing in liquid N2, the sample was dried under vacuum at room temperature.
The temperature resistance of a p(AM/AA/AMPS/APEG) solution with a mass fraction of 0.6 wt.% was tested at 160°C using a rotary rheometer at a shear rate of 170 s− 1. The shear resistance test was conducted at 120°C and 140°C using a 0.3 wt.% p(AM/AA/AMPS/APEG) aqueous solution, a frequency of 1 Hz, and a stress scanning range of 0.1–10 Pa. The viscoelastic properties of p(AM/AA/AMPS/APEG) were tested at 30°C with a frequency scanning range of 0.1–10 Hz and a stress of 1 Pa.
FTIR spectroscopy analysis
The FTIR spectra of the APEG monomer and the p(AM/AA/AMPS/APEG) polymer are shown in Fig. 1.
The FTIR spectrum of p(AM/AA/AMPS/APEG) showed the stretching vibration peaks of the N–H bond in the amide group and the O–H bond in the carboxyl group at 3192 cm− 1. The stretching vibration peaks of the saturated C–H bond and the C = O bond appeared at 2935 and 1668 cm− 1, respectively. The bending vibration peak of the N–H bond of the primary amine in the amide group appeared at 1552 cm− 1, and the stretching vibration peak of the sulfonic acid group was observed at 1329 cm− 1. The bending vibration peak of the C–O–C bond of the functional monomer APEG and p(AM/AA/AMPS/APEG) appeared at 1182 cm− 1. These results indicate that the functional monomer underwent successfully the polymerization reaction and the obtained molecular structure is consistent with the design polymer structure.
1 H NMR spectroscopy analysis
Figure 2 shows the 1H NMR spectrum of the p(AM/AA/AMPS/APEG) polymer.
The following peaks were observed: the deuterium oxide solvent peak at δ 4.78 (g); the peak of –CH3 in the –(CH3)2CCH2– side chain at δ 1.11 (d); the peak of the –CH2SO3– group in AMPS at δ 3.58 (e); the peak of the –OCH2CH2– repeating unit in the APEG monomer side chain at δ 4.15 (f); the –CH– peak of –CH2–CH– in APEG at δ 1.71 (c); the –CH2– peak of the–CH2–CH– repeating unit in the main chain of p(AM/AA/AMPS/APEG) at δ 1.73 (a); the –CH– peak of the–CH2–CH– repeating unit in the main chain of p(AM/AA/AMPS/APEG) at δ 1.43 (b). The results showed that the APEG monomer participated in the polymerization reaction, and the molecular structure of the obtained polymer was consistent with the design.
Particle size distribution analysis
The particle size of the emulsion before and after the polymerization was determined using a laser particle size analyzer. As shown in Fig. 3, the particle size distribution in the pre-emulsified solution before the polymerization reaction was not uniform, and the particle size was larger than that of the emulsion after the polymerization reaction. Conversely, the average particle size distribution of the water-in-oil emulsion of p(AM/AA/AMPS/APEG) after the polymerization reaction was concentrated and uniform. The particle size (D50) of the emulsion before the polymerization reaction was 13.60 µm, and that after the polymerization reaction was 7.129 µm. During the pre-emulsification process, the emulsifier forms a surface-active film at the oil–water interface, encapsulating the functional monomer to form a water-in-oil droplet. Upon stirring, the free radicals formed by the decomposition of the initiator enter the solubilized micelles, and the polymerization is initiated, forming a stable structure with a uniform and concentrated particle size distribution.
Critical association concentration test
Figure 4 shows the effect of the mass fraction of p(AM/AA/AMPS/APEG) on the apparent viscosity, revealing that the apparent viscosity of the p(AM/AA/AMPS/APEG) solution is proportional to the mass fraction. In the low concentration stage, the apparent viscosity of the p(AM/AA/AMPS/APEG) solution increases uniformly and slowly. With increasing polymer mass fraction after a certain value, which corresponds to the critical association concentration of p(AM/AA/AMPS/APEG) (K in Fig. 4), the apparent viscosity increases sharply. When the polymer concentration is lower than the K value, there are fewer polymer macromolecules in the solution, thus decreasing the number of intramolecular association microregions, which are formed by the hydrophobic interaction between the hydrophobic groups of the polymer. When the polymer concentration is greater than the K value, the intermolecular entanglement and intermolecular association become stronger, inducing the formation of a multilayer spatial network structure with increased density in the aqueous solution. Therefore, when the polymer concentration exceeds the K value, the viscosity of the polymer solution increases substantially.
SEM analysis
Figure 5 SEM images of the p(AM/AA/AMPS/APEG) polymer in (a, b) water, (c) 10000 mg/L NaCl solution, and (d) 10000mg/L CaCl2 solution
Figures 5(a) and 5(b) show that the molecular chains of p(AM/AA/AMPS/APEG) in aqueous solution are intertwined to form a tight spatial network structure. This is due to the intermolecular hydrophobic association of the polyethylene glycol groups and the hydroxyl groups in the polymer. According to Figs. 5(c), 5(d), and 6, a large number of sulfonic acid groups in the polymer can associate with metal salt ions. The addition of abundant salt ions hinders the formation of the original hydrogen bonds; however, the hydrodynamic volume increases. Figure 6 shows that the polymer surface has a hydrophobic layer, which renders it repulsive to water. In a high salinity environment, the hydrophobic groups or side chains of p(AM/AA/AMPS/APEG) can form hydrophobic associations with water molecules, reducing the contact between salt ions and water molecules. As a result, p(AM/AA/AMPS/APEG) exhibits excellent salt resistance.
Analysis of salt tolerance
Figure 7 shows the apparent viscosity of p(AM/AA/AMPS/APEG) solutions with concentrations of 0.3, 0.5, and 0.8 wt.% as a function of the concentration of monovalent NaCl and divalent CaCl2 salt solutions.
With increasing NaCl concentration, the viscosity of the p(AM/AA/AMPS/APEG) solution gradually decreases until eventually stabilizing. When the concentration of the salt solution increases to 10000 mg/L, the viscosity of the polymer solution increases considerably. This is due to the fact that the emulsion contains abundant sulfonic acid and carboxylic acid groups that quickly stick and increase the viscosity at high salt concentration. These groups can form a network structure via hydrogen bonding and electrostatic interaction and can continuously associate and ion-exchange with metal cations, finally forming a stable structure that increases the apparent viscosity of the emulsion. When the concentration of the CaCl2 divalent salt is low, the thickening effect of the salt increases the viscosity of the solution, which makes the emulsifier ineffective at the oil–water interface, resulting in the destabilization of the emulsion and decreasing the apparent viscosity.
Analysis of temperature resistance
To determine the temperature resistance of the polymer, p(AM/AA/AMPS/APEG) solutions with a concentration of 0.6 wt.% were prepared in water, 20000 mg/L NaCl solution, and CaCl2 solution, respectively. The heating rate was set to 0.1°C/s, the heating range was 30°C–160°C, and the shear rate was 170 s− 1. The test results are shown in Fig. 8.
For conventional water-soluble polymers, the viscosity of the solution decreases with increasing temperature. However, the hydrophobic association is an entropy-driven endothermic process. Within a certain range, the increase in temperature is beneficial for the association and formation of a network structure and improves the temperature resistance and shear resistance of the solution. With increasing polymer concentration, the viscosity retention rate increases. This is due to the increase in the polymer concentration enhancing the probability of hydrophobic monomer association [23]. Figure 8 shows the rheological properties of a 0.6 wt.% polymer solution in different salt solutions upon increasing the temperature up to 160°C. The viscosity of the p(AM/AA/AMPS/APEG) solution decreased with increasing shear temperature. When the temperature reached 160°C, the viscosity of each solution after shearing for 60 min was 63.52, 45.06, and 32.07 mPa·s, respectively. At lower temperatures, the intermolecular interaction is strong, resulting in an orderly arrangement of polymer molecules and the formation of a more compact structure, thereby increasing the viscosity. However, as the temperature increases, the intermolecular interaction weakens, and the polymer molecules become more loosely arranged, decreasing the viscosity. The Na+ and Ca2+ ions in the brine can interact with the hydroxyl groups of the polymer molecules, resulting in a stable final viscosity. Pu[24] et al. developed a new type of fracturing fluid with a self-made β-cyclodextrin-functionalized hydrophobic associating polymer and a viscoelastic surfactant as the main components. After continuous shearing for 120 min in clear water at 118°C, the apparent viscosity retention value of a 0.6 wt.% polymer solution was only 58.8 mPa·s. Under the same concentration and high temperature conditions, p(AM/AA/AMPS/APEG) showed better temperature resistance.
Analysis of shear resistance
Aqueous solutions of p(AM/AA/AMPS/APEG) with mass fractions of 0.6 and 0.8 wt.% were prepared and tested for temperature and shear resistance. The results are shown in Figs. 9 and 10. Moreover, a p(AM/AA/AMPS/APEG) solution with a concentration of 0.8 wt.% was subjected to temperature and shear resistance tests at 120°C and 140°C in NaCl and CaCl2 media, respectively. The results are shown in Figs. 11 and 12.
As shown in Fig. 9, when the shear performance of the 0.6 wt.% p(AM/AA/AMPS/APEG) solution was tested at 120°C, the viscosity of the polymer solution decreased with increasing temperature and shear time. After shearing for 60 min, the residual viscosity was 61.48 mPa·s. Upon increasing the temperature, the viscosity of the p(AM/AA/AMPS/APEG) solution increased due to the association of the polymer molecular chains. According to Fig. 10, the viscosity of the 0.8 wt.% p(AM/AA/AMPS/APEG) solution was 76.32 mPa·s after shearing at 120°C for 60 min. The viscosity change trend is basically the same for the 0.6 and 0.8 wt.% p(AM/AA/AMPS/APEG) solutions, with the viscosity increasing slightly and then decreasing gradually.
The viscosity of 0.8 wt.% p(AM/AA/AMPS/APEG) in a 20000 mg/L NaCl solution after shearing for 1 h at 120°C and 140°C was 72.11 and 64.88 mPa·s, respectively, which changed to 65.85 and 56.77 mPa·s after shearing in a 20000 mg/L CaCl2 solution for 1 h. This shows that the introduction of the APEG monomer improved substantially the temperature resistance of the polymer. The presence of allyl groups increases the linear entanglement between molecules, resulting in a denser spatial network structure. Therefore, the introduction of APEG in the polymer is conducive to the formation of a complex spatial network via linear entanglement and hydrophobic association, which helps increase the viscosity of the polymer solution. More importantly, at high polymer concentration, the spatial network structure is more conducive to the formation of a dynamic crosslinked intermolecular linear entanglement and hydrophobic association structure, resulting in a large-scale supramolecular structure with enhanced temperature and shear resistance.
Thixotropic properties of the p(AM/AA/AMPS/APEG) polymer
The thixotropic properties of p(AM/AA/AMPS/APEG) aqueous solutions with mass fractions of 0.3、0.5and 0.7 wt.% were tested,and the results are shown in Fig. 13.
Thixotropy is a polymer property that refers to microstructure changes and a decrease in consistency that occur when the polymer is subjected to external force and the subsequent recovery of the original state when the external action disappears[25]. The larger the closed ring area, the better the thixotropy of the p(AM/AA/AMPS/APEG) solution. The thixotropy of p(AM/AA/AMPS/APEG) is shown in Fig. 13. As the shear rate increases, the shear stress in the polymer solution gradually increases, the spatial network structure is reversibly destroyed, and the polymer molecules are randomly oriented, resulting in a decrease in viscosity. As the shear rate decreases, the spatial network structure is reorganized, resulting in a viscosity recovery. A comparison between the thixotropic loops of p(AM/AA/AMPS/APEG) solutions at different concentrations revealed that the higher the concentration of the polymer solution, the greater the shear stress required. The maximum shear stresses of 0.3, 0.5, and 0.7 wt.% p(AM/AA/AMPS/APEG) solutions were 8.685, 23.97, and 34.54 Pa, respectively. This shows that the energy required to destroy the network structure at high concentration is larger than that at low concentration. Under the condition of enhanced association, the polymer exhibits better thixotropy, which can enhance not only the synergistic effect of the rigid hydrophobic association and linear entanglement, but also the tightness of the polymer space network structure.
Analysis of viscoelastic variation of polymer
Figures 14 and 15 show the changes in the energy storage/elastic modulus (G') and the energy dissipation/viscous modulus (G") of a 0.3 wt.% p(AM/AA/AMPS/APEG) solution with frequency and stress in clear water, 10000 mg/L NaCl and CaCl2 solutions, and 20000 mg/L NaCl and CaCl2 solutions.
The G′ and G′′ values reflects the elasticity and viscosity of the polymer, respectively. The viscoelasticity of a copolymer plays a key role in polymer fracturing. The G′ and G′′ values increase with increasing frequency. According to the results, the G′ of p(AM/AA/AMPS/APEG) in salt aqueous solutions is greater than G′′, reflecting the elastic behavior of the solution. With increasing salt concentration, the p(AM/AA/AMPS/APEG) solution showed better viscoelastic properties. In clear water, the G′ value of the polymer solution exceeds the G′′, value as the frequency increases, with the elastic properties playing a leading role. At low frequencies, the p(AM/AA/AMPS/APEG) molecular chains become curled, and the intramolecular hydrophobic interaction dominates. At high frequencies, the molecular chains are stretched and the hydrophobic interaction between molecules is enhanced. As a result, G ′ increases rapidly.
To improve the temperature resistance, salt resistance, and shear resistance of hydrophobically associating polymers, the hydrophobic monomer APEG was introduced into the inverse emulsion polymerization system to prepare a hydrophobically associating polymer. The resulting p(AM/AA/AMPS/APEG) was Characterized via FTIR and 1H MNR spectroscopy, which confirmed that the functional monomer APEG was successfully introduced into the polymer. SEM observation showed that p(AM/AA/AMPS/APEG) maintained a dense and complete spatial network structure in salt water.
The temperature and shear resistance test showed that the viscosity of 0.6 and 0.8 wt.% polymer aqueous solutions was 61.48 and 66.32 mPa·s, respectively, at 120 °C and a shear rate of 170 s−1. Meanwhile, at 120 °C and 140 °C, the viscosity of the polymer salt solution with a mass fraction of 0.8 wt.% was greater than 56 mPa·s. The thixotropy test results showed that the polymer exhibited good shear recovery performance. The viscoelastic test results revealed that 0.3 wt.% p(AM/AA/AMPS/APEG) dissolved in monovalent and divalent salt solutions underwent a transition from a viscous body to an elastomer, demonstrating its good viscoelasticity.
Data Availability
Data will be made available on request.
Acknowledgements
This research was supported by the Qin-Chuangyuan "Scientist+Engineer" Team Construction Project (2024QCY-KXJ-052), the Key R & D Program of Shaanxi Province (2024GX-YBXM-393), the Industrialization Project of Shaanxi Provincial Education Department (23JC008) in China.
Conflict of interest The author assures that they have no financial or personal relationships that would have appeared to conflict with or appear to have an impact on their work.
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