Influence Of Particle Size Research Articles

Influence of Bi co-catalyst particle size on the photocatalytic activity of BiOI microflowers in Bi/BiOI junctions – A mechanistic study of charge carrier behaviour

Herein, we investigate the effect of Bi particle size in BiOI/Bi junctions on their photocatalytic function towards NO gas. BiOI microflowers (BiOI) and BiOI microflowers decorated with micron-sized Bi particles (BiOI/Bi MPs) were produced by a solvothermal method. BiOI decorated with nano-sized Bi particles (BiOI/Bi NPs) were produced by a reduction process. All samples were physically characterised by XRD, FT-IR, SEM, HR-TEM coupled with EDX analysis, DR-UV–visible and PL spectroscopy and functionally characterised by photocatalytic testing towards NO gas, TAS and EPR spectroscopy.Their photocatalytic activity towards NO gas was measured following ISO protocol (ISO 22197–1:2016). The best performing BiOI-based sample was BiOI/Bi NPs, showing NO and NOx conversion efficiencies of ∼33 and ∼11% under UVA light, and ∼26 and ∼8.1% under visible light, respectively. The BiOI and BiOI/Bi MPs samples showed significantly lower activities, displaying overall NOx conversion efficiencies of ∼3.5 and ∼0.8% under UVA light, respectively. Importantly, the best performing BiOI/Bi NPs samples showed visible light activity that was at least 6 times higher than that of a commercial TiO2 benchmark (CristalACTiVTM PC-S7). TAS measurements showed that charge carriers were significantly longer lived in the BiOI/Bi NPs sample (t50% from 10 μs of ∼90 μs) than the BiOI and BiOI/Bi MPs samples (t50% from 10 μs of ∼50 μs). This was attributed to the significant degree of interfacial contact formed between Bi and BiOI in the BiOI/Bi NPs sample, which enhanced charge carrier separation. EPR studies showed that this interfacial contact between BiOI and Bi likely promoted the formation of VO, which may have contributed to enhancement seen in photocatalytic activity in the BiOI/Bi junction.

Preparation and cooling performance analysis of double-layer radiative cooling hybrid coatings with TiO2/SiO2/Si3N4 micron particles

Passive daytime radiative cooling is achieved by radiating heat into outer space through electromagnetic waves without energy consumption. A scalable double-layer coating with a mixture of TiO2, SiO2, and Si3N4 micron particles for radiative cooling is proposed in this study. The finite-difference time-domain algorithm is used to analyze the influence of particle size and coating thickness on radiative cooling performance. The results of the simulation show that the particle size of 3 μm can give the best cooling performance, and the coating thickness should be above 25 μm for SiO2 coating. Meanwhile, the mixture of SiO2 and Si3N4 significantly improves the overall emissivity. Through sample preparation and characterization, the mixture coating with a 1:1 ratio addition on an Al substrate exhibits high reflectivity with a value of 87.6% in the solar spectrum, and an average emissivity of 92% in the infrared region (2.5 μm–15 μm), which can be attributed to the synergy among the optical properties of the material. Both coatings can theoretically be cooled by about 8 °C during the day and about 21 °C at nighttime with h c = 4 W⋅m−2⋅K−1. Furthermore, even considering the significant conduction and convection exchanges, the cooling effect persists. Outdoor experimental results show that the temperature of the double-layer radiative cooling coating is always lower than the ambient temperature under direct sunlight during the day, and can be cooled by about 5 °C on average, while lower than the temperature of the aluminum film by almost 12 °C.

Influence of Grinding Methodology and Particle Size on Coal and Wood Co-Combustion via Injection Flame Opening Angle

Today, more than 61% of the world’s electricity is generated by burning fossil fuels. The search for reducing the negative impact of such thermal power plants on the environment does not stop for a minute, one of the solutions to this problem is the partial replacement of coal with biomass. This method has proven itself most effective over the past five years. Co-pulverized combustion of coal and biomass has not found wide practical application, since the processes of grinding, mixing and subsequent spraying of such mixed fuels have not been fully studied. This study compares the influence of the method of grinding, mixing coal and biomass on the processes of spraying mixtures with a change in the pressure of the atomizing air. The results of the research showed that the joint grinding of coal and biomass contributes to the achievement of the minimum size of coal and wood and, as a result, leads to an increase in the opening angle of the torch, which will significantly improve the efficiency of flame combustion in the furnace space at the station. The most effective spray pressure of the mixed fuels was established, which was 3 bar. An analysis of the results obtained during the course of the research allows us to conclude that the mixing of coal and sawmill waste, followed by joint grinding in a ball mill, contributes to the effective grinding of biomass and coal particles to a finely dispersed state, which subsequently leads to a significant increase in the opening angle of the torch at any concentration of the mixture composition fuels.

Indium Recycling from Waste Liquid Crystal Displays: Is It Possible?

The utilization of valuable properties of waste and their reuse as raw materials is an imperative of the circular economy. Waste electrical and electronic equipment (WEEE) is a significant source of valuable raw materials, certain metals, and rare earth elements that are the basis for highly sophisticated IT equipment production. It is estimated that the production of WEEE in Europe in 2019 was 16.20 kg/inhabitant, while quantities continue to grow at a rate of 3–4% per year. Waste liquid crystal displays used in televisions, laptops, desktops, and other devices represent a significant share of WEEE and contain 0.12–0.14% of liquid crystals whose main ingredient is indium—tin oxide. In order to investigate and determine the methods and conditions of indium recycling from waste LCDs, laboratory research was conducted. The influence of temperature, particle size, and retention time in different media with and without ultrasound treatment was monitored to provide the efficiency of indium leaching. The analysis of the results showed that 98% indium leaching was achieved with granulation samples of 10 × 10 mm at a temperature 40 °C/40 min in solution H2O:HCl: HNO3 = 6:2:1 under ultrasound conditions, while aqueous and alkaline media under the same conditions did not show significant efficiency. This study can be used as a practical reference for the recycling of indium from LCD panels.

Influence of particle size on electrorheological effect of poly(ionic liquid) microsphere suspensions

Hydrophobic poly(ionic liquid) microspheres with different sizes are prepared via cooling assisted phase separation method. The morphology and structure of microspheres are characterized by scanning electron microscope, Fourier transform infrared spectroscopy, differential scanning calorimetry, and thermogravimetric analysis. The effect of particle size on the electrorheological effect of the poly(ionic liquid) microsphere suspensions is studied by rheological test under electric fields. It shows that the shear stress at zero electric field decreases with the increase of particle size, while yield stress and electric field-induced shear stress increase with the increase of particle size. The electric field dependence of yield stress and electric field-induced shear stress increment is independent of particle size.

Incorporating fluoropolymer-coated micron-sized aluminum with enhanced reactivity into aluminized explosives to improve their detonation performance

Micro-sized aluminum (m-Al) has been widely applied in explosives as fuel additives. Unfortunately, m-Al displays long ignition delay and insufficient combustion, making it fail to fully release its energy in aluminized explosives. In this work, fluoropolymer-coated m-Al composites were prepared using the solvent evaporation method. Then, the surface state of the m-Al composites was determined based on scanning electron microscopy (SEM) images, and their thermal behavior was investigated through thermogravimetric analysis (TGA) at a temperature range of 30–1200 ​°C. Moreover, the reactivity and combustion kinetics of aluminum were explored using laser ignition experiments. To evaluate the metal acceleration ability and detonation performance of CL-20-based explosives containing fluoropolymer-coated m-Al composites, the disc acceleration experiment (DAX) was specially designed taking into account the influence of aluminum particle size. The results of this study show that fluoropolymers were uniformly distributed on the surface of m-Al, and most of the as-prepared particles were microspheres without apparent agglomeration. The presence of fluoropolymers is beneficial to the oxidation of aluminum particles. The explosive sample containing fluoropolymer-coated aluminum composites exhibited shortened ignition delay and an increase in the burning speed from 3.3 ​mm·s−1 to 7.9 ​mm·s−1 compared to the sample with uncoated Al. Most especially, its specific kinetic energy increased from 8.45 ​kJ·g−1 to 9.29 ​kJ·g−1, its detonation velocity increased from 7.75 ​km·s−1 to 7.82 ​km·s−1, and its detonation pressure increased from 25.57 ​GPa to 30.89 ​GPa.

Effects of particle concentration and size on the dissipation rate and turbulent kinetic energy of oil

AbstractThe presence of particles in oil can change the quasi‐sequence structure of the turbulent flow of the oil, and it is extremely important to explore the turbulent energy dissipation rate of the particulate‐containing oil and ensure the safe and stable operation of the oil‐using equipment. Thus, the flow field of the oil containing particles in the pipeline was experimentally studied by a particle image velocimeter (PIV); the turbulent kinetic energy of the oil was calculated using the transient velocity vector field measured by the PIV; and the dissipation rate distribution was calculated using the large eddy PIV method. The influence of different particle sizes and particle concentrations on the normal distribution of the turbulent kinetic energy and dissipation rate was analyzed. The results show that the distribution of the turbulent kinetic energy in the normal direction is non‐unidirectional and in a parabolic shape. The 25 μm particle size has a great influence on the turbulence kinetic energy and the dissipation rate of the oil; with increasing particle concentration, the flow field distribution of the turbulent kinetic energy increases in the region near the wall, and gradually decreases in the central region. The turbulent kinetic energy distribution of the oil is in the shape of a quasi‐cosine; the flow field of the dissipation rate is larger in the near‐wall region and the central region and shows an inverted ‘W’ shape. This provides a theoretical basis for improving the efficiency of oil transportation, discussing the monitoring of particulate matter in oil, and reducing oil pollution.

Experimental Investigation of the Influence of Weight Percentage, Particle Size, and Heat Treatment on the Properties of SiC Particle Reinforced: A356 Aluminum Matrix Composite

Experimental Investigation of the Influence of Weight Percentage, Particle Size, and Heat Treatment on the Properties of SiC Particle Reinforced: A356 Aluminum Matrix Composite

Mechanism of porous ceramic fabrication using Second Aluminum Dross assisted by corn stalk as pore-forming agent

Second Aluminum Dross (SAD), a byproduct of aluminum dross extraction with both resource and pollutant properties, requires harmless treatment and full-component utilization. This study focuses on using corn stalks as a pore-forming agent to create porous ceramics with SAD. The role of corn stalk in pore formation was investigated, and the influence of stalk particle size, content, pyrolysis, and calcination conditions on pore formation in porous ceramics was analyzed. Sample analysis using XRD, XRF, BET, TEM, and SEM revealed the phase composition, component content, and microstructure of the ceramics. The results indicate two forms of pores: micron-sized pores produced by the reaction between corn stalk and oxygen at high temperatures and nano-sized pores left by water vapor in the colloid channel. The porous ceramics had a polycrystalline structure consisting of numerous crystals ranging from 15–50 nm in size, and the polycrystalline component was Al2O3. Corn stalk promotes pore formation, creating a loose and uniform sample with a specific surface area of 174.83m2/g, a porosity of 0.58 cm 3/g, and an average pore size of 124.65 nm. The paper outlines a process for the harmless treatment and high-value utilization of SAD as a raw material, which significantly reduces the cost of raw materials and solves the solid waste disposal problem in the aluminum industry.

Effect of foam stabilization on the properties of foamed concrete modified by expanded polystyrene

This paper aims to study the modified foamed concrete by mixing expanded polystyrene (EPS) particles. In order to analyze the influence of EPS particle dosage and particle size on the mechanical properties and thermal conductivity of the foamed concrete, the EPS modified foamed concrete was compared with the ordinary foamed concrete. The pore structures of the foamed concrete with and without EPS were characterized and compared by scanning electronic microscopy (SEM), mercury intrusion porosimetry (MIP), and image-pro plus (IPP). The results showed that when large and small size EPS replaced 60% foam, the water absorption of the EPS modified foamed concrete was approximately 38% and 55% lower than that of the ordinary foamed concrete, respectively, with a corresponding 0.13 and 0.5 MPa increase in compressive strength. In addition, the thermal conductivity of the EPS modified foamed concrete was similar to/even slightly lower than that of the ordinary foamed concrete. The addition of EPS in foamed concrete increased the proportion of small connected pores and reduced the proportion of medium and large pores. Overall, the addition of EPS in foamed concrete can effectively improve the stability.

Mortars with recycled aggregate of construction and demolition waste: Mechanical properties and carbon uptake

Over the past few years, the use of recycled aggregate (RA) from construction and demolition waste (CDW) has proved to be a promising alternative for increasing the concept of a circular economy within the construction industry. RA contributes to an adequate destination for these wastes besides minimizing the use of natural aggregates (NA). Carbonation also has proved to be a promising alternative to carbon capture, use, and storage. This work aims to evaluate the substitution influence of NA for RA in replacement levels of 0, 25, 50, 75, and 100% with three different particle size distributions to evaluate the particle size influence. Compressive and tensile strength in bending, porosity, absorption, and bulk density were performed to evaluate physical–mechanical properties. The accelerated carbonation test and thermogravimetric analysis were carried out to evaluate the carbon uptake. X-ray microtomography test was carried out in addition to XRD analysis to assess the influence on microstructural properties. The particle size distribution interferes with the results, where washing the aggregate does not significantly improve the investigated properties. The mortar with the optimized properties contained particles between 2.4 mm and 0.15 mm (G2.4). The less emissive mortar was G2.4_100, which reabsorbs 63% of all the carbon dioxide released in production. The mortars with 100% replacement have a less emissive balance, and the replacement level increases the amount of CO2 captured. Cement-based mortars produced with RA can be an alternative for carbon capture due to mineralization from carbonation, promoting the circular economy using RA from CDW.

A green and sustainable water evaporation-induced electricity generator with woody biochar

The generation of electricity through the natural process of water evaporation has emerged as a promising method of energy conversion. However, many advanced generators utilizing this technique, known as water evaporation-induced electric generators (WEIGs), feature a complicated fabrication process and lack output stability, hindering their practical use in real-world applications. In this study, we present a facile fabrication of an efficient WEIG based on woody biochar (WBC). WBC was prepared from lignocellulosic feedstocks (LCFs) in a tube furnace and then mixed with ethyl cellulose (EC) and ethanol to acquire a homogeneous slurry. WEIG was then fabricated in air pyrolysis after casting the slurry with a silicone pad. A key advantage of this material is the presence of hydrophilic functional groups in WBC, which allows for constant, sustainable generation of electricity from water without the need for additional hydrophilic treatments. For the first time, we thoroughly examined the formation process of WBC and evaluated the impact of WBC derived from three different components of LCFs on electricity generation. Additionally, we analyzed the electricity generation mechanism of WBC-based WEIG and the influence of botanical origin, particle size, and carbonization temperature of WBC on the electrical properties. Our findings indicate that lignin-rich WBC is particularly well-suited for use in WEIGs, suggesting the potential for widespread adoption of LCFs in hydro-voltaic power generation. Under ambient conditions, a single WEIG device was able to achieve a maximum open-circuit voltage (VOC) of 0.42 V and a short-circuit current (ISC) of 528 nA. Furthermore, when multiple devices were connected in series, a VOC of 7 V was attained, sufficient to power small commercial electronics. The implementation of these findings has the potential to pave the way for the development of green energy generators through the utilization of water evaporation on WBC.

Effects of activated carbon particle size on the formation of hydrate in fully/partially saturated liquid phase system

ABSTRACT As a porous medium with rich pore structure, activated carbon (AC) was once considered the best carrier for hydrate storage and transportation. However, the harsh conditions of the hydrate reaction in the wet carbon environment have always limited the sufficient and rapid formation of hydrate. Therefore, the influences of particle size (4–8, 8–16, 20–40 and 100 mesh) and liquid phase saturation (fully/partially saturated) in the sodium dodecyl sulfate system on hydrate reaction were investigated. The results showed that small particle in the fully saturated liquid phase system led to the increase in hydrate generation rate, with the highest hydrate reaction rate of 3.16 mmol/min in the 100 mesh AC layer, which was 1.7–2.9 times higher than other AC layers. The gas storage capability of the 4–8 mesh AC layer with a water saturation of 70% was the highest among all systems, reaching 0.198 mol/mol. The saturation of the liquid phase induced the nucleation and growth of hydrates. Adherently growing hydrates of fully saturated liquid phase systems and mushroom-like hydrates of partially saturated liquid phase systems were found in turn. This research facilitates the commercialization of AC-based hydrate technology.

Tribological behavior of sintered electrolytic iron‐zinc stearate added compacts

AbstractPowder metallurgy is an effective method to give near net shape to powder particles. In this paper, the influence of powder particle size, lubricant and compaction load on hardness and wear loss has been investigated as it influences the compact. Electrolytic iron powder (250 mesh to 300 mesh and 300 mesh to 350 mesh) with zinc stearate (0 weight % to 2 weight %) was used for preparing the samples. Green samples were prepared by cold compaction process at different loads (400 kN, 450 kN and 500 kN). Pre‐sintering was done at 550 °C. Taguchi′s (L18) mixed level model was used to develop the regression equation for hardness and wear loss. The maximum hardness of 79 HRB was achieved with 300 mesh to 350 mesh particle size and 500 kN compaction load. Minimum wear volume loss was observed with samples having composition of 250 mesh to 300 mesh size electrolytic iron powder at 500 kN compaction load and 1 weight % lubricant content.

Influence of characteristic parameters of SiC reinforcements on mechanical properties of AlSi10Mg matrix composites by powder metallurgy

The bottleneck problems of SiC particles reinforced AlSi10Mg composites (SiC/AlSi10Mg) prepared by traditional casting method, such as composition segregation, interface reaction and coarse microstructure, can be effectively improved by powder metallurgy with lower processing temperature. In this study, the influence of SiC particle size and content on the properties of SiC/AlSi10Mg was systematically analyzed. SiC/AlSi10Mg composites were prepared by planetary ball milling, spark plasma sintering (SPS) and hot extrusion composite preparation process. The obtained composites presents dense microstructure without the formation of interfacial reaction phase. The distribution of micron SiC particles (μm-SiC) in the matrix is relatively uniform, and nano SiC particles (nm-SiC) slightly agglomerates with the increase of the content. The strength of SiC/AlSi10Mg increases with the increase of nm-SiC content, which is mainly attributed to dispersion strengthening, dislocation strengthening and grain refinement strengthening. The strength of SiC/AlSi10Mg hardly changes with the increase of μm-SiC content, but the elongation decreases gradually. The deformation between μm-SiC and AlSi10Mg matrix is not coordinated and μm-SiC cleave the AlSi10Mg matrix. The irregular boundaries of μm-SiC are easy to produce stress concentration during loading, leading to interface cracking or μm-SiC fracture. Therefore, μm-SiC are difficult to play a significant strengthening effect to composites. With the increase of SiC content, the fracture mechanism of composites gradually changes from ductile fracture to brittle fracture in SiC agglomeration region. This study lays a theoretical and experimental foundation for the controllable preparation and performance optimization of high strength and toughness AMCs reinforced by SiC particles.

Size effect of iron oxide nanorods with controlled aspect ratio on magneto-responsive behavior

Iron oxide (Fe3O4) has been widely used as a magnetic material for magnetorheological (MR) fluids due to its facile geometric control, magnetic properties, and surface functionalization. However, studies on controlling the aspect ratio of iron oxide nanoparticles applied to MR fluids have rarely been reported due to difficulties in preparing anisotropic magnetic particles. To gain insight into the application of anisotropic nanoparticle in MR fluids, in this work iron oxide nanorods are prepared by using β-FeOOH nanorods as a template. The size of the β-FeOOH nanorods is controlled by adding polyethyleneimine (PEI) as the size controlling agent, and further reduction results in iron oxide nanorods. The resulting iron oxide nanorods are uniform in size and shape and exhibit superparamagnetic properties and high magnetic saturation, which is suitable for MR applications. The influence of particle size of the iron oxide nanorods on MR properties is evaluated, and the result shows the MR fluids prepared with larger size nanorods exhibit higher shear stress due to the higher magnetic saturation ascribed to larger crystalline domain. Consequently, gaining control over the size and aspect ratio of the magnetic particles can lead to high performance MR fluids.

Dialysis is a key factor modulating interactions between critical process parameters during the microfluidic preparation of lipid nanoparticles

Manufacturing lipid nanoparticles through microfluidic mixing can be approached from a Quality by Design perspective. Research involving critical process parameters seems to focus on the total flow and flow rate ratio, thus other process variables, such as dialysis, are underestimated. This study used a Design of Experiments to identify the influence of critical process parameters on particle size, polydispersity index, and zeta potential. A response surface Design of Experiments modeled the influence of: total flow (400 to 4000 μL min-1); flow rate ratio (3 to 9) and dialysis (yes/no). Results suggest that dialysis is a crucial parameter that strongly influences particle size and zeta potential and moderately affects polydispersity index. The flow rate ratio's relevance decreases when dialysis is performed. As the purification method can change the influence of other process parameters, it should be an integrated part of the microfluidic manufacturing of lipid nanoparticles instead of an extra step.

In-cloud scavenging of chemically segregated particle types by individual particle observation

While aerosol plays a significant role in the formation of cloud, the in-cloud scavenging of chemically segregated particle types were still insufficiently investigated and the controlling factors remain ambiguous. Several field observations were carried out during 2018–2021 at Mt. Tianjing (1690 m a.s.l.) in southern China, based on ground-based counterflow virtual impactor (GCVI)-single particle aerosol mass spectrometer (SPAMS), to investigate the in-cloud scavenging (activation) of various particle types, including black carbon (BC), organic-containing particles (OC), mineral dust (Dust), metal-containing particles (Metal), potassium-rich particles (K-rich) and sea salt (SS). GCVI was used to sample cloud droplet residual particles (Res) while PM2.5 inlet sampled interstitial particles (Inter) during cloud events and ambient particles (Amb) on sunny days, respectively. Different types of particles were recognized based on spectral characteristics obtained by the SPAMS. Based on the coupled GCVI-SPAMS measurements, the number-based scavenging efficiencies (NSEs) of various particle types could be quantified. Besides, the influence of liquid water content (LWC), PM2.5, particle size, and mixing state on the NSEs were discussed. The NSE of SS was the highest (32.4%) while OC showed the lowest NSE (9.1%). Other particle types shared similar NSEs with all the detected particles, with an average of ∼20–25%. Apart from OC, NSEs of other types of particles increased with the increase of LWC and decreased with the increase of the concentration of PM2.5, suggesting that numerous PM2.5 suppressed particles entering cloud droplets via competing for water vapor. The annual variations of NSEs were generally in accordance with LWC and PM2.5, reflecting the certain role of these environment conditions. The NSEs typically increased with particle size in a range of 0.2–2.0 μm, reflecting the dominant nucleation mechanism during in-cloud scavenging. Particles mixed with sulfate and nitrate were easier to be scavenged than those coated with organic compounds, e.g., the discrepancy reached 11.8% for the K-rich particles.

Surface modification of anhydrous phosphogypsum and its application in isotactic polypropylene

Phosphogypsum (PG) is a by-product of the wet phosphoric acid process, and anhydrous phosphogypsum (APG) prepared by PG calcination and ball milling pretreatment can be useful to prepare polypropylene composites by melt blending to yield polymer materials with improved properties. In this work, the hydrophobic effect of stearic acid (SA) modified APG was investigated by various analytical techniques. To this end, the modified APG was used as a filler for isotactic polypropylene (PP) blending to yield PP/APG composites and study the influence of APG particle size and added amount on the mechanical properties of PP/APG composites. The results showed SA coated on APG surface by chemical adsorption to form a hydrophobic layer. The water contact angle increased from 8.49° to 112.49° before to after modification, respectively. The mechanical properties of PP/APG composites were affected by the particle size and content of APG. Smaller particle size of APG led to better mechanical properties of PP/APG composites. At particle size d50 of APG filler of 2.83 μm and content of 5 wt%, characteristics like the tensile strength, flexural strength, impact strength, and tensile modulus of PP/APG composites reached 37.28 MPa, 47.71 MPa, 6.18 KJ/m2, and 422.3 MPa, respectively. Compared to pure PP, these values increased by 4.66%, 5.4%, 27.68%, and 18.28%, respectively. Smaller particle size of APG was also found more conducive to the increase in APG content within PP/APG composites, as well as reduced production cost of composites. APG prepared from PG after treatment is useful as a filler for PP and other polymer materials, promising for PG resource utilization.

Quantitative analysis of amorphous form in indomethacin binary polymorphic mixtures using infrared spectroscopy analytical techniques combined with chemometrics methods

Pharmaceutical corporations prefer amorphous active pharmaceutical ingredients (APIs) because of their high apparent solubility and bioavailability, which are caused by long-range disorder, large unit surface free energy, and easily wetted particle surfaces. APIs in amorphous form tend to recrystallize into crystalline form during production, transportation, and storage, leading to differences in safety and clinical efficacy, which has been a major obstacle to development of amorphous drugs. In this study, rapid and nondestructive methods for quantitative analysis of amorphous indomethacin (A-INDO) content in A-INDO and γ-indomethacin (γ-INDO) binary mixtures were established based on Attenuated Total Reflection Fourier Transform Infrared spectroscopy (ATR-FTIR) and Near-Infrared spectroscopy (NIR) combined with chemometrics methods. Partial least squares regression (PLSR) was used to establish quantitative analysis models of A-INDO content ranging from 0.000 % to 10.000 % w/w %. A variety of spectral pretreatment methods were used to pretreat the spectral, reducing the influence of inconsistent particle size and uneven mixing, and highlighting the sample component information. The two analytical techniques’ best PLSR models were selected, and the performance of the best models was confirmed by the validation samples. The most effective PLSR model based on ATR-FTIR was Y = 0.99456 X + 0.21526, R2 = 0.99456, the limit of detection (LOD) was 0.714 % and the limit of quantification (LOQ) was 2.164 %. The optimal PLSR model based on NIR was Y = 0.99950 X + 0.07465, R2 = 0.99950, with LOD = 0.246 % and LOQ = 0.747 %. The results showed that the PLSR models established by ATR-FTIR and NIR solid-state analytical techniques combined with stoichiometric method could be used to detect the content of amorphous APIs and to control the production quality of APIs.