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Soil caves collapse are typical geological hazards in karst areas. The disintegration of red clay is one of the important mechanisms leading to soil caves collapse. The pH of the soil pore solution has changed due to acid rains and the overuse of fertilizers. This study conducted disintegration tests to observe the disintegration rate of red clay in solutions with different pH values by a self-made disintegration apparatus. The inductively coupled plasma mass spectrometer (ICP-MS) and Zeta potential analyzer were used to test the cations concentration in the solutions and the electric potential (ζ potential) of red clay, analyzing the effect of pH on the physicochemical properties and the disintegration rate of red clay, providing a scientific basis for evaluating and preventing soil caves collapse. The results show that the disintegration rate in solutions with different pH values follows the order of pH = 11 > pH = 9 > pH = 3 > pH = 5 > pH = 7. When pH < 7, the cations concentration and the cations charges density in the soil solutions increased as the pH decreases. The electric potential changed from negative to positive as the pH decreases, with the potential value first decreasing and then increasing. When pH > 7, the cations concentration, cations charges density in the soil solutions, and the electric potential increased with the pH increased. The ratio of charges density to electric potential increased under both acidic and alkaline conditions, the thickness of the clay diffusion layer decreased, short-range gravitational decayed and repulsion increased, ultimately leading to the disintegration of red clay. [ABSTRACT FROM AUTHOR]

AbstractIn this article, n-eicosane@MUF phase change microcapsules were prepared by in-situ polymerization with n-eicosane as the core material and melamine urea-formaldehyde (MUF) resin as the shell material. The effects of pH values from 3.5 to 6.0 on the surface morphology, particle size distribution, latent heat of phase transformation, encapsulation degree, thermal stability, and permeability resistance of the microcapsules were investigated. The results showed that the surfaces of the microcapsules gradually became smooth with the increase of pH value, and their encapsulation degree and impermeability also increased roughly. When the pH = 5.5, the particle size of the microcapsule samples ranged from 1.5 to 9.7 μm, the melting enthalpy was 178.8 J/g, and the encapsulation degree was 86.6%, which had the best thermal stability and impermeability. However, when the pH = 6.0, the phenomenon of microcapsule shell rupture occurred and the above performance no longer occurred. [ABSTRACT FROM AUTHOR]

Magnesium potassium phosphate hexahydrate (MgKPO4·6H2O) was used as solidification matrix to immobilize some radioactive element and some heavy metal ions, the stability of MgKPO4·6H2O under different conditions had become the focus. This work gives new insights on the stability of synthesized MgKPO4·6H2O in the different temperatures and pH values solutions. The solid phase transformed from synthesized MgKPO4·6H2O was characterized by X‐ray diffractometer (XRD), thermal gravity analysis (TG/DSC), Fourier‐transform infrared spectrum (FTIR) and scanning electron microscope (SEM) at different temperature and pH values solution. Results indicated MgKPO4·6H2O had almost no phase transition at the temperature of 50°C and 60°C. Mg3(PO4)2·22H2O appears with the increase of solution temperature. The main phase is MgKPO4·6H2O at the pH of 9 and 12, minor MgHPO4·3H2O formed at the pH of 6, next Mg3(PO4)2·22H2O formed at the pH of 3 and 6. High pH value environment is beneficial for the maintenance of MgKPO4·6H2O. This study is an important guidance for the application of MgKPO4·6H2O crystal. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Irrigation & Drainage is the property of Journal of Irrigation & Drainage Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

To explore formation and failure mechanism of rebar passivation film in the liquid-phase environment of alkali-activated slag (AAS) system, AAS cementitious material systems with different mixing designs were prepared. The time-dependent evolution of the pH value of AAS real pore solution was studied in various factors such as different types of activator, alkali equivalent, water-glass modulus, fly ash addition, and curing time. In addition, the generation time, composition, thickness, and critical chloride threshold of rebar passivation film in simulated pore solution were monitored and analyzed over time. The results show that the pH value of AAS real pore solution decreases with the increase of curing time, with pH values of all samples remaining above 12. 8 at 28 d. The increase in pH value in the simulated pore solution reduces the formation time of rebar passivation film, increases its thickness, and enhances its resistance to chloride ion erosion. The characteristic of AAS real pore solution having a higher pH value can provide a more favorable liquid phase environment for the stable existence of rebar passivation film, thereby improving the long-term performance of reinforced concrete structures. [ABSTRACT FROM AUTHOR]

Copyright of Irrigation & Drainage is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Petroleum Refinery Engineering is the property of Petroleum Refinery Engineering Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The present study reports the synthesis of cobalt ferrite nanoparticles (CoFe 2 O 4 NPs) using the sol-gel precipitation process via mixing a stoichiometric ratio of cobalt chloride (1 M) and ferric chloride (2 M). The molar of ferric to cobalt was mentioned (2:1) and then 2 M of sodium hydroxide was added. The structural and morphological features of the material were assessed using X-ray diffraction (XRD), Scanning electron microscopy (SEM), and atomic force microscopy (AFM). The electrical properties were analyzed using an LCR meter, while the magnetic properties were measured using a vibrating sample magnetometer (VSM). Fourier-transform infrared spectroscopy (FTIR) investigated the material's molecular vibrations. The X-ray diffraction (XRD) analysis revealed that all the samples exhibited a cubic spinal structure, and no additional peak was detected. Interestingly, the average size of the crystallites (D) decreased from 17.74 nm to 16.58 nm as the pH level increased from 7 to 13. This finding provides important insights into the behaviour of the tested samples under different pH conditions. The formation of the ferrite spine was confirmed by FTIR spectroscopy, with the primary detected bands (408.92–470.65 cm−1) attributed to the octahedral complexes and (516.94–588.31 cm−1) assigned to the tetrahedral ones. The dielectric and imaginary part of the dielectric constant decreased with increasing pH values excluding samples prepared at pH = 11. All samples with different pH values exhibit resonance peaks at frequencies up to (1 KHz). The magnetic measurements carried out by the VSM instrument, the result show that the saturation magnetization increases with increasing pH and the higher saturation magnetization is 68 emu. g1. [ABSTRACT FROM AUTHOR]

An experimental investigation has been made into the effects of a high-intensity impact on the pH value and temperature of water. Water pH and temperature dynamics has been determined at various regimes of acoustic impact on the specimens. Acoustic impact regimes have been established at which there is a maximum rise in the pH value and a drop in temperature. The dependence of the heat transfer rate on the intensity of acoustic vibrations has been defined. A comparison has been made of the obtained experimental results on variation of water pH in cooling with a known dependence. The results obtained in this investigation have been compared with experimental data of other authors who have investigated the behavior of water pH in ultrasonic, laser, electromagnetic, and mechanical impacts. [ABSTRACT FROM AUTHOR]

Objective To evaluate the preservation effect of normothermic mechanical perfusion with red blood cells from humanized genetically modified pig on severed human limbs. Methods Severed human limbs were perfused with red blood cells from humanized genetically modified pigs for 6 h. Perfusion solution was taken every hour to measure the oxygen partial pressure, Na+, K+, Ca2+, pH value, glucose, lactic acid and creatine kinase levels. Superficial flexor muscle was sampled to detect the changes of tumor necrosis factor (TNF)-α, interleukin (IL)-2 and IL-1 levels. At 0 and 6 h after perfusion, the superficial flexor muscles of the forearm were taken for pathological examination. Intercellular space and glycogen consumption of skeletal muscles were observed. An appropriate amount of forearm vessels was collected every 2 h to detect the apoptosis of vascular endothelial cells. X-ray angiography was performed before perfusion and 6 h after perfusion to observe the filling degree of finger-tip peripheral vessels. Results The oxygen partial pressure was observed in the normal range throughout the perfusion. Na+ concentration peaked at 1 h, reaching 138.7 mmol/L, and then fluctuated within the normal range. K+ level peaked at 2 h up to 6.08 mmol/L, then decreased and fluctuated within the normal range. Ca2+ concentration reached the peak at 4 h, up to 1.03 mmol/L. Glucose level was gradually decreased at the beginning of perfusion, reaching the lowest value of 17.7 mmol/L at 2h after perfusion, and then maintained a dynamic balance. The pH value was decreased to 7.28 at 6 h after perfusion. The lactic acid level was increased to 9.6 mmol/L at 1 h after perfusion, and then gradually decreased. The creatine kinase level was increased at the start of perfusion, reached the peak at 2 h up to 20 030 U/L, then decreased and remained stable at the end of perfusion. At the end of perfusion, the morphology of muscle fibers was normal, the gap among muscle fibers was expanded slightly, and the glycogen of skeletal muscles was not significantly accumulated. At 0 h perfusion, the number of apoptotic cells in vascular endothelial cells was large, which was declined at 6 h perfusion. Evident vascular filling was observed at 0 h, and the filling degree of some finger-tip vessels was decreased at 6 h. Conclusions Normothermic mechanical perfusion of severed human limbs with red blood cells from humanized genetically modified pigs may continuously and stably supply energy and oxygen, adjust the ion pH balance of perfusion solution, maintain normal cellular metabolism and exerts certain protective effect upon severed human limbs. [ABSTRACT FROM AUTHOR]

【Objective】 Panax Notoginseng is a medicinal herb and primarily grown in Southern China. This paper investigates the impact of irrigation and fertilization on soil potassium and pH, as well as yield and quality of Panax Notoginseng. 【Method】 The experiment was conducted in Dalishu Village, Luxi County, located in the Honghe Hani and Yi Autonomous Prefecture, Yunnan Province. It consisted of four fertilizations by applying the 480 kg/hm2 of fertilizers at different ratios in the seedling, flowering, fruiting and root gain stages: 25%∶25%∶25%∶25%(F1), 25%∶30%∶20%∶25%(F2), 30%∶30%∶15%∶25%(F3), and 40%∶20%∶10%∶30%(F4). Each fertilization had three irrigation treatments: 200 m3/hm2(W1), 300 m3/hm2(W2) and 400 m3/hm2(W3). The control (CK) was F1 combined with 92 m3/hm2 of irrigation. In each treatment, we measured the changes in soil potassium content and pH. The technique for order preference by similarity to ideal solution (TOPSIS) was used to evaluate all treatments. 【Result】 ① When irrigation and fertilization were the same, soil pH decreased with soil depth and tended to stabilize as the crop grew. The soil pH showed little sensitive to fertilization. When irrigation was the same, the average soil pH was lower in the four treatments than in the CK. During the experimental period, pH of the 0-60 cm soil in different treatments varied from 4.80-8.66. W3F1, W2F4 and W2F3 gave the optimal soil pH for the crop to grow. ② Both total and available soil potassium decreased with increasing soil depth. As the crop grew, the total potassium in the 0-60 cm soil layer increased, while the available potassium decreased initially before increasing. With increasing irrigation amount, total soil potassium decreased, while the available potassium increased initially followed by a decline. Fertilization influenced the dynamics of total and available potassium. Irrespective of fertilization and irrigation, potassium uptake by roots in different growing stages was ranked as follows: fruiting period>flowering period>root weight gain period>seedling stage. Of all the treatments, W2F3 was optimal for soil potassium, with total and available potassium being 10.40 g/kg and 56.69 mg/kg, respectively. ③ Regardless of fertilization, with the increase in irrigation amount, the yield and partial factor productivity (PFP) of the crop increased first followed by a decline. The yield, water use efficiency and PFP varied with fertilization. TOPSIS analysis showed that the optimal irrigation was 300 m3/hm2 and the optimal fertilization was applying 144, 144, 72 kg/hm2 and 120 kg/hm2 of fertilizers in the seedling, flowering, fruiting and root weight gain stage, respectively. 【Conclusion】 Based on soil potassium, pH, as well as yield and quality of Panax Notoginseng, the optimal irrigation and fertilization for Panax Notoginseng production in the studied area were irrigating 300 m3/hm2 and applying 144, 144, 72 kg/hm2 and 120 kg/hm2 of fertilizers in the seedling, flowering, fruiting and root weight gain stage, respectively.

This paper investigated the influence of ultraviolet (UV) illumination on the corrosion behavior of 7A04 aluminum alloy in 3.5% NaCl solutions with various pH values (pH=5.0, 7.0, and 10.0) using weight loss measurement, electrochemical methods, and surface analysis techniques. The research results indicated that the corrosion products of 7A04 alloy in salt solutions with different pH values all exhibited n-type semiconductor properties and could trigger the photovoltaic effect under UV illumination. Simultaneously, UV illumination reduced the compactness of the corrosion products, inhibited the enrichment of copper compounds (Cu2O), and promoted the generation of hydroxyl radicals in the solution. Therefore, UV illumination significantly accelerated the corrosion process of 7A04 alloy, with the overall acceleration effect ranking as follows: alkaline > neutral > acidic. In addition, the corrosion mechanism of 7A04 alloy in the test solutions with and without UV illumination was also discussed in this paper.

This is an article in the field of mining engineering. The diatomite was modified with sodium dodecyl sulfonate and ferroferric oxide, and the influence of external factors on the adsorption effect was analyzed. And the experiment of the phase composition change and the microstructure change after the modified diatomite adsorbs heavy metal ions was carried out. The results show that when the modified diatomite content is 4 g/L, the adsorption time is 40 min, the temperature is set to 30 ℃, the pH value is set to 5, and the initial concentration is set to 200 mg/L, the adsorption of the modified diatomite is relatively good. The fitting degree of the Freundlich model to the test curve is above 0.90, and the fitting degree of the Langmuir model to the test curve is below 0.9, which shows that the Freundlich isotherm adsorption model is more suitable for the change law of the adsorption of heavy metal lead ions on modified diatomite. There is no significant difference in the characteristic diffraction peaks of the XRD pattern before and after the adsorption of lead ions on the modified diatomite. Only the peak intensity of the diffraction peak is reduced. However, the other mineral components inside the modified diatomite remain unchanged and the structure does not change significantly. This also shows that modified diatomaceous earth can effectively adsorb lead ions in sewage. However, the adsorption process is basically physical adsorption.

Background: Autoimmune gastritis (AIG) is an infrequent disease predisposing to both neuroendocrine tumours and cancer. This study aimed to evaluate whether pH measurement of gastric juice allows accurate exclusion of the presence of AIG in real time so that gastric mucosa sampling on normal-appearing mucosa may be avoided. Methods: This study enrolled patients diagnosed with AIG and matched controls (ratio 1:5) who underwent upper endoscopy with standard gastric mucosa sampling and real-time, gastric juice pH assessment. A threshold of pH less than 4.5 was adopted as cut-off to rule out the presence of a feature of AIG. Sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), overall accuracy, positive likelihood ratio (LR+), and negative likelihood ratio (LR−) were calculated. Results: Data of 40 patients (M/F: 19/21; mean age: 58 years, range: 18–89) with AIG and 212 matched controls were evaluated. Among AIG patients, the feature of atrophy/metaplasia of the oxyntic mucosa was staged as mild in 9 cases, moderate in 9, and severe in the remaining 22 patients. Gastric juice analysis showed a pH value >4.5 in 29 (72.5%) patients and 12 (5.7%) controls. Sensitivity, specificity, accuracy, PPV, NPV, LR+, and LR− were 73% (95% CI = 0.57–0.84), 94% (95% CI = 0.90–0.97), 71% (95% CI = 0.64–0.74), 95% (95% CI = 0.93–0.97), 91% (95% CI = 0.87–0.95), 12.9 (95% CI = 7.19–23.03), and 0.29 (95% CI = 0.18–0.48), respectively. The histological assessment of false-negative cases showed the presence of only mild-moderate atrophy of oxyntic mucosa in 6 (54.5%) cases, and severe in the others. Conclusions: Our data found that real-time pH evaluation of gastric juice allows ruling out AIG with a very high NPV, but further studies are needed.

This research aim is to activate water using a plasma jet that works with argon gas and to study the effect of the plasma on the physicochemical properties of the water. The plasma consists of a power supply capable of supplying a high alternating voltage of up to 12 kV in the form of a sinusoidal wave with a frequency of 20 kHz. The temperature of the produced plasma (Te) was (1.028) eV, and its electron density (ne) was (4.392×1017) cm-3 at a flow rate of 1L/min. The physicochemical properties of the water are determined by determining the concentration of each of NO2, NO3, and H2O2, the pH of the water, and the water temperature during exposure to the plasma. The effect of storage time on the properties of the activated water is determined after 48 hours of exposure to plasma. The RONS species were measured using kits purchased from USA (Bartovation) Company manufactured for this purpose. The pH was measured with a pH meter, and the working gas temperature was remotely measured with an IR thermometer. The concentration of the three active species increases with exposure time, but the active species NO2 concentration decreases to zero at an exposure time of 120 minutes. The concentrations of the three components decrease with the decrease in the flow rate. The pH decreases with the exposure time until it reaches 2, and the temperature increases until it reaches 35oC. The concentration of NO3 increases with the increase of the water storage time. In the case of H2O2, the concentration increases slightly, then after 10 hours it begins to decrease exponentially, reaching a value close to zero after the passage of 48 hours. For NO2, its concentration begins to decrease exponentially from the start of storage and reaches a concentration close to zero after 48 hours of storage. The pH increases with the storage time, and the water reaches its natural state with a pH of 7 after 48 hours of storage. From this, it is concluded that the best storage time for PAW is ten minutes after the end of the activation process, and also that the activation time should be short, but not exceeding ten minutes. [ABSTRACT FROM AUTHOR]

Copyright of Bulletin of Soil & Water Conservation is the property of Bulletin of Soil & Water Conservation Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This paper presents an extensive comparative analysis of the experimental results of chemical stabilisation of clayey soil in laboratory conditions by comparing the effects of adding conventional stabilisers (lime, cement binder), stabilisers that can be considered as waste material (fly ash, rock flour), as well as alternative chloride-based materials (ferric chloride, calcium chloride, potassium chloride) on the geomechanical properties of the soil. With the aim of determining the stabiliser optimal content in the mixture with the soil, in the first part of the research, the effects of stabilisation of clayey soil of medium plasticity using the considered stabilisers with different percentage share on the change in uniaxial compressive strength (UCS) and pH value of the soil at different time intervals after the treatment were analysed. In the second part of the research, additional tests were conducted on soil samples with optimal content for each of the considered stabilisers by monitoring changes in the physical and mechanical properties of the soil. These include Atterberg's limits (liquid limit and plasticity limit), modulus of compressibility in the oedometer, California bearing ratio (CBR), and swelling potential at different time intervals after the chemical treatment to determine the durability of stabilisation effects. The results of the conducted research reveal that each of the conventional, waste, and alternative materials considered as chemical stabilisers contributes to the improvement of the geomechanical properties of the clayey soil, primarily in terms of increasing the bearing capacity and reducing the swelling of the treated soil. [ABSTRACT FROM AUTHOR]

Fruit salad is a healthy food because it is rich in fiber and vitamins. To give flavor to fruit salad, salad dressing can be added. One of the ingredients that can be added as a salad dressing is soygurt. However, in making soygurt, skim milk used to increase total solids is not fat so it needs to be re-evaluated using organoleptic test, pH value and total solids to be used as fruit salad dressing. This research aims to fill the knowledge gap by systematically investigating the effect of soygurt addition on organoleptic quality, pH value, and total soluble solids in fruit salad dressing. The method used in this research is an experiment conducted with three formulations, namely, 25%, 50%, and 75%. The way to determine the quality of soygurt addition to fruit salad dressing is organoleptic test, pH value, and total soluble solids. The results showed that the addition of soygurt by 50% in fruit salad dressing products produced the best quality in the aspects of color, aroma, viscosity, sweetness, sourness, and soybean languish. The total soluble solids test showed a significant difference with the 75% percentage having the highest value, which was 15.33 brix°. Organoleptic assessment of the quality of color, aroma, viscosity, sweetness, sourness, and soybean tartness showed that there was no significant difference between the addition of 25%, 50%, and 75% soygurt. [ABSTRACT FROM AUTHOR]

Copyright of Silicone Material is the property of Silicone Material Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The investigation concluded that the water quality of the Gomti river was found to be severely polluted. The Gomti River was determined to have a poor physicochemical condition, indicating significant hazards and rendering it unsuitable for any purpose. In the present investigation, the pH value measured at Daliganj was 7.33±0.29, which slightly exceeded the optimal range. Conversely, the lowest recorded pH level (pH 5±1) was found in close proximity to the riverbank. Biological oxygen demand (BOD) concentration serves as a dependable biomarker for water pollution. The existence of Dissolved Oxygen (DO) is vital for the survival of fish and other aquatic creatures, and its levels are directly influenced by water temperature. The water at Daliganj had the highest reported level of Biochemical Oxygen Demand (BOD), measuring 21.67 mg/l. However, the lowest recorded value was observed at the Lat riverbank, measuring 14.33 mg/l. The river is extensively polluted as a result of the release of home and industrial garbage through multiple drainage systems. The rise in total hardness value was attributed to household discharges. The water in the Shaheed Smarak locality has elevated levels of Chemical Oxygen Demand (COD). The water quality declined as a result of the drainage system throughout its vicinity. The main cause of pollution is the diverse range of industrial, agricultural and household waste, leading to an increase in the amount of garbage being dumped into the river. Consequently, there is an increase in the concentration of toxic heavy metals, resulting in the pollution of river water. The river's self-purification capacity has been impeded due to the accumulation of both organic and inorganic debris, leading to a rise in bacterial growth. Hence, it is imperative to eliminate the biological burden prior to its entry into the river, with the aim of safeguarding the well-being of both humans and aquatic organisms. The Gomati River is experiencing water contamination due to the presence of pollutants. [ABSTRACT FROM AUTHOR]

Copyright of Multipurpose Utilization of Mineral Resources / Kuangchan Zonghe Liyong is the property of Multipurpose Utilization of Mineral Resources Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The aim of this study was to investigate the effects on beer turbidity after dry-hopping. Firstly, depending on the quantity of hop pellets added and secondly, when varying the dosing point while maintaining a constant hopping rate. Selected chemical and physical properties of the finished beer were also investigated for both scenarios (quantity and time of dry-hopping). Both the "trial quantity" (TQ) and "trial timing" (TT) resulted in significant effects with regards to the increase in turbidity in the dry-hopped beers. Gradually increasing dry-hop dosing rates in TQ correlated well with the greater turbidity according to both methods used, MEBAK and OD600. All dry-hopped beers in TT showed a significant increase in turbidity compared to the base beer. This haze was further intensified with a very late dry-hop dosage at the end of maturation. The turbidity was, along with other selected variables, also analysed after the beer had been stored for 6 months at 20 °C, "trial storage" (TS). Both, the supernatant formed after storage and the homogenised beers were investigated. The results of the stored and homogenised samples showed highly comparable and, in some cases identical results compared to analyses of freshly bottled beers of TQ and TT. The effect of the dry-hopping variations of TQ and TT could still be demonstrated analytically in the supernatants and visually in the settled beers. Pictures were taken to visualise the behaviour of the various dry-hopped beers to link the results to the visual expectations that consumers have of commercially available beers. [ABSTRACT FROM AUTHOR]

Copyright of Food Research & Development is the property of Food Research & Development Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The commercial tin oxide (SnO2) colloidal suspension is widely utilized as an electron transport layer (ETL) in high‐performance perovskite solar cells (PSCs). However, despite significant efforts have been proposed to address bulk transport and interface recombination issues, the PSC efficiency is still limited to around 25%. In this study, the crucial role of the physicochemical characteristics of the SnO2 colloidal suspension in shaping the morphology, electrical properties, and optical properties of the SnO2 ETL is investigated. By controlling the pH value of the SnO2 solution with weak acids such as carbonic acid, the reassembly of metal oxide nanoparticles into smaller sizes with more homogeneous dispersion and dense interconnections is successfully induced. Consequently, the resulting SnO2 ETL exhibits enhanced crystallinity, high conductivity, low surface defects, and high optical transmittance. As a result, the efficiency of the target PSC is increased from 23.10% (control device) to 24.70%. This improvement is attributed to higher voltage, photocurrent, and fill factor compared to the relevant control samples. A similar device improvement using phosphoric acid is observed, indicating that the approach represents a universal technique to further enhance the quality of SnO2 ETL for large‐area, high‐efficiency, and stable PSCs. [ABSTRACT FROM AUTHOR]

Due to the miniaturization of equipment for flow chemistry and microprocess engineering, low-cost sensors and analytical devices are becoming increasingly important for automated inline process control and monitoring. The combination of 3D printing technology and open-source lab automation facilitates the creation of a microfluidic toolbox containing tailored actuators and sensors for flow chemistry, enabling a flexible and adaptable design and efficient processing and control based on the measured data. This contribution presents a set of 3D-printed microfluidic sensor flow cells for inline measurement of temperature, electrical conductivity (EC), and pH value, while compensating for the temperature dependence of EC and pH. The tailored sensor flow cells were tested using model reactions in a single-phase capillary flow system. They have an accuracy comparable to reference sensors in batch measurements. The sensor data can be used to monitor the reaction progress (conversion), determine the kinetic data (activation energy, pre-exponential factors) of saponification reactions, and identify titration characteristics (equivalence and isoelectric points) of neutralization reactions. Hence, the 3D-printed microfluidic sensor flow cells offer an attractive alternative to commercial analytical flow devices for open-source and low-cost lab automation. [ABSTRACT FROM AUTHOR]

As pH is a key factor affecting the quality of maize silage, its accurate detection is essential to ensuring product quality. Although traditional methods for testing the pH of maize silage feed are widely used, the procedures are often complex and time-consuming and may damage the sample. This study presents a non-destructive hyperspectral imaging (HSI) technology that provides a more efficient and cost-effective method of monitoring pH by capturing the spectral information of samples and analyzing their chemical and physical properties rapidly and without contact. We applied four spectral preprocessing methods, among which the multiplicative scatter correction (MSC) preprocessing method yielded the best results. To minimize model redundancy and enhance predictive performance, we utilized six feature extraction methods for characteristic wavelength extraction, integrating these with partial least squares (PLS), non-linear support vector machine regression (SVR), and extreme learning machine (ELM) algorithms to construct a quantitative pH value prediction model. The results showed that the model based on the bootstrapping soft shrinkage (BOSS) feature wavelength extraction method outperformed the other feature extraction methods, selecting 20 pH value-related feature wavelengths from 256 bands and building a stable BOSS–ELM model with prediction set determination coefficient (R P 2 ), root-mean-square error of prediction (RMSEP), and relative percentage deviation (RPD) values of 0.9241, 0.4372, and 3.6565, respectively. To further optimize the model for precisely predicting pH at each pixel in hyperspectral images, we employed three algorithms: the genetic algorithm (GA), whale optimization algorithm (WOA), and bald eagle search (BES). These algorithms optimized and compared the BOSS–ELM model to obtain the best model for predicting maize silage pH: the BOSS–BES–ELM model. This model achieved a determination coefficient ( R P 2) of 0.9598, an RMSEP of 0.3216, and an RPD of 5.1448. We generated a visualized distribution map of pH value variation in maize silage using the BOSS–BES–ELM model. This study provides strong technical support and a reference for the rapid, non-destructive detection of maize silage pH from an image, an advancement of great significance to ensuring the quality of maize silage. [ABSTRACT FROM AUTHOR]

This study investigates the development of a low-alkali eco-friendly solidifying agent (SA) for dredged sludge using cement (C), steel slag powder (SSP), granulated blast-furnace slag (GGBFS), and phosphorus gypsum (PG). First, an orthogonal test design is employed to determine optimal proportions. The impact of material components on the unrestricted compressive strength (UCS), water absorption, pH, and microstructure of the solidified dredging sludge (SDS) is studied across varying initial water contents. Then, key factors affecting UCS development are identified as cement, GGBFS, and curing age. The pH of SDS decreases to 8.5–9.5 at 28 days, attributed to the continuous reduction in alkalinity facilitated by GGBFS reacting with Ca(OH)2. At last, life cycle assessment (LCA) highlights the practical and ecological advantages of ratios C4-G8 and C6-G6. This research contributes valuable insights into the efficient and eco-friendly solidification of dredged sludge. [ABSTRACT FROM AUTHOR]

The aim of this study was to evaluate the impact of sumac on the oxidation status, sensory properties, and physicochemical and microbiological parameters of common carp (Cyprinus carpio) fish during chilled storage. Fillets of carp were treated with ground sumac at percentages of 0% (T0), 0.5% (T1), 1.5% (T2) and 2.5% (T3) and analysed after 24 and 72 h of chilled storage. The fat content, oxidation parameters (thiobarbituric acid reactive substances, TBARS), antioxidant capacity, total volatile basic nitrogen (TVB-N), free fatty acids (FFA), sensory properties, colour indicators (lightness L*, redness a*, yellowness b*), water activity, pH value, aerobic plate count (APC), psychrotrophic microorganism count (PMC), and coliform bacteria count were determined. The TBARS values of T1, T2, and T3 decreased significantly (p < 0.05) after 24 h of chilled storage. The antioxidant capacity increased in a dose-dependent and time-dependent manner. As regards organoleptic properties, sumac was able to reduce the natural fishy odour, increase the sour odour and flavour, and mask the fish odour and flavour significantly. A significant effect of sumac on the redness (a*) values of muscles was observed, which increased with elevation of the sumac ratio. A decrease in fillet pH and lower APC and PMC were observed. No effect was found on water activity or the growth of coliform bacteria. The study found that sumac plays a role in the oxidation status, pH value and organoleptic properties of fish fillets, which could be beneficial for the fish and fishery products industry. [ABSTRACT FROM AUTHOR]

：The downhole tubes were fractured and perforated after 5 years of shut-in due to high water cuts. This study employs a comprehensive array of analytical techniques to investigate the mechanisms behind fractures and perforations. Utilizing non-destructive testing (NDT), direct reading spectrometer, tensile strength testing machine, impact testing machine, optical microscope (OM), macroscopic fracture morphology observation, scanning electron microscope (SEM) and energy spectrum analysis (EDS), and sulfide stress corrosion cracking (SSCC) was studied. The reason for the fracture of the tubing is that under the condition of low pH value, high hydrogen sulfide environment, the tubing is fractured due to stress concentration caused by cracks in the outer thread relief groove. The perforation of the inner tube wall was caused by gradual wall thickness reduction under the influence of H2S, CO2, and Cl−, resulting in fouling and eventual perforation. To prevent tube corrosion during long-term shut-in, it is recommended to inject crude oil or diesel into the well.

This study investigated the pH of four popular Nepalese tea brands such as Tokla, Ridhisidhi, Suman, and Muna, under different conditions to assess their acidity and potential health implications. The teas were prepared using standardized brewing methods, and pH measurements were taken at room temperature and after chilling to observe any temperature-related variations. Freshly brewed teas tended to be more alkaline, while those with added sugar and lemon were more acidic. Temperature changes had minimal impact on pH, indicating that acidity remains stable whether the tea is consumed hot or cold. While the pH range of these teas is generally safe for consumption, it may cause discomfort for those with acid sensitivity. These findings provide insights into the acidity of Nepalese teas and its potential effects on sensory and health attributes.

This study aimed to analyze the microbial contamination of chicken meat and its pH value from traditional markets in Banyuwangi, East Java to ensure public health. A total of 30 raw chicken meat samples from three traditional markets were used in this study and examined for the presence of Escherichia coli and Salmonella spp. E. coli and Salmonella spp. were identified using Gram staining, culturing, and biochemical tests. The Most Probable Number (MPN) method was used for coliform and E. coli. Measuring the pH value of chicken meat was carried out after purchasing the meat and 24 hours after storage at cold temperatures. The results showed coliform contamination in all samples with an average of >1100 CFU/G with E. coli contamination of 20% (6/30), exceeding the maximum recommended limit. Furthermore, the identification of Salmonella spp. in all samples showed negative results. Chicken meat pH value decreased with the length of postmortem time; immediately after purchase (0 hours), the pH value was 5.78 ± 0.26, and after 24 hours of storage, it raised 6.02 ± 0.28. In conclusion, there was high coliform contamination out of 30 raw chicken meat samples taken from some traditional markets in Banyuwangi. Furthermore, E. coli contamination was as much as 20%, and Salmonella spp. was negative.

Compared with the traditional ammonium acetate exchange method and calcium acetate exchange method to determine cation exchange capacity (CEC), hexamminecobalt trichloride method has obvious advantages in the analysis of large quantities of samples. However, the application scope of this method is limited, and the detection results of neutral and alkaline samples are good, but the detection results of acidic samples are as low as 50%. In order to solve these problems, the pH was adjusted to alkaline with 2mol/L sodium hydroxide solution, the CEC value of the sample was significantly improved, and the determination results of both acidic and alkaline samples reached the range of standard values. By drawing the pH adjustment curve, the volume of 2mol/L sodium hydroxide solution was obtained in soil samples with different pH ranges, so as to adjust the pH value of unknown samples and realize the accurate determination of CEC. On the basis of the original method, the pH of the sample was adjusted to alkalinity, and the precision of the optimized method ranged from 1.02% to 3.82% (n=6). After optimization, the application scope of the method is expanded, the precision and accuracy are improved, and the detection efficiency of a large number of samples is effectively improved. [ABSTRACT FROM AUTHOR]

In this study, we evaluated the pH (potential of hydrogen) value of diabetic foot ulcers and explored the relationship between the pH value and infection, sinus formation, stasis dermatitis, and the process of healing. From October 2022 to June 2023, 99 patients with 106 diabetic foot ulcers were selected. Diabetic foot ulcers were treated in a standardized manner by a professional team. The pH value, area, PUSH (Pressure Ulcer Scale for Healing) score, and the degree of infection of the wounds were compared before and after the treatment. The baseline wound pH value in 76.4% of the patients was in the alkaline range and was closely related to the degree of infection (P < 0.05). As the ulcers healed, the pH decreased. For moderately and severely infected diabetic foot ulcers, each unit decrease in pH was associated with a decrease in the PUSH score of approximately 4.6 points (P < 0.05). The pH values of wounds with surrounding ecchymosis dermatitis were significantly higher than those of wounds without ecchymosis dermatitis (P < 0.05). The pH value of the wound with a sinus tract was higher. After treatment, there was no significant difference in pH value between the patients with and without sinus tracts (P < 0.05). The measurement of pH value is efficient and simple, and the patient suffers no discomfort in the process. The change in pH helps predict the healing process of diabetic foot ulcers and quickly identify whether there are key factors such as infection and ischemia in the wound. It is suggested that dynamic pH monitoring be included in the whole course evaluation and intervention strategy development of diabetic foot. • Diabetic foot ulcers commonly have an alkaline pH, which is closely associated with infection severity and wound healing. • Decreasing pH levels during ulcer healing are linked to improvements in the PUSH score. • Diabetic foot ulcers with surrounding ecchymosis dermatitis exhibit significantly higher pH values. • The presence of a sinus tract in the wound does not significantly impact the pH value after treatment. • Monitoring pH value is an effective approach to predict healing progress and guide intervention strategies. [ABSTRACT FROM AUTHOR]

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In the face of ongoing water pollution challenges, the intricate interplay between dissolved organic matter and disinfectants like chlorine gives rise to potentially harmful disinfection byproducts (DBPs) during water treatment. The exploration of DBP formation originating from amino acids (AA) is a critical focus of global research. Aromatic DBPs, in particular, have garnered considerable attention due to their markedly higher toxicity compared to their aliphatic counterparts. This work seeks to advance the understanding of DBP formation by investigating chlorination disinfection and kinetics using tyrosine (Tyr), phenylalanine (Phe), and tryptophan (Trp) as precursors. Via rigorous experiments, a total of 15 distinct DBPs with accurate molecular structures were successfully identified. The chlorination of all three AAs yielded highly toxic chlorophenylacetonitriles (CPANs), and the disinfectant dosage and pH value of the reaction system potentially influence chlorination kinetics. Notably, Phe exhibited the highest degradation rate compared to Tyr and Trp, at both the CAA:CHOCl ratio of within 1:2 and a wide pH range (6.0 to 9.0). Additionally, a neutral pH environment triggered the maximal reaction rates of the three AAs, while an acidic condition may reduce their reactivity. Overall, this study aims to augment the DBP database and foster a deeper comprehension of the DBP formation and relevant kinetics underlying the chlorination of aromatic AAs. [ABSTRACT FROM AUTHOR]

This study aimed to analyze the microbial contamination of chicken meat and its pH value from traditional markets in Banyuwangi, East Java to ensure public health. A total of 30 raw chicken meat samples from three traditional markets were used in this study and examined for the presence of Escherichia coli and Salmonella spp. E. coli and Salmonella spp. were identified using Gram staining, culturing, and biochemical tests. The Most Probable Number (MPN) method was used for coliform and E. coli. Measuring the pH value of chicken meat was carried out after purchasing the meat and 24 hours after storage at cold temperatures. The results showed coliform contamination in all samples with an average of >1100 CFU/G with E. coli contamination of 20% (6/30), exceeding the maximum recommended limit. Furthermore, the identification of Salmonella spp. in all samples showed negative results. Chicken meat pH value decreased with the length of postmortem time; immediately after purchase (0 hours), the pH value was 5.78 ± 0.26, and after 24 hours of storage, it raised 6.02 ± 0.28. In conclusion, there was high coliform contamination out of 30 raw chicken meat samples taken from some traditional markets in Banyuwangi. Furthermore, E. coli contamination was as much as 20%, and Salmonella spp. was negative. [ABSTRACT FROM AUTHOR]

Peatland restoration usually aims at restarting the peatlands' function to store carbon within peat. The soil properties of the near-surface peat can give a first understanding of this process. Therefore, we sampled pH value, total organic carbon content (TOC), total nitrogen content (TN), C/N ratio as well as dry bulk density (BD), and describe the structure of near-surface peats in six restored fens in North-East Germany before (2002-2004) and after (2019-2021) restoration. Before restoration, the study sites showed peat degradation to various extents in their near-surface peats. pH values remained relatively stable over time. Comparing the degraded peat horizons, TOC increased significantly in four study sites, ranging from 35.7% to 47.8% in 2002-2004 and from 42.5% to 54.0% in 2019-2021. TN varied from 1.5% to 3.5% in 2002-2004 and from 1.8% to 3.2% in 2019-2021, but changes were only significant in one site, showing a slight decrease. In three sites, the increase in C/N ratio was significant, indicating lower nutrient availability. BD ranged from 0.08 to 0.48 g/cm3 in 2002-2004 and from 0.10 to 0.16 g/cm³ in 2019-2021, decreasing significantly in four sites. The structure of the degraded peat horizons changed after restoration to a more homogenous, sludge mass with larger re-aggregates. In three sites, new peat moss peat layers above the degraded soil horizon were present in 2019-2021, with a mean thickness of 6.8 to 36.1 cm. The structure was comparable to typical, slightly decomposed peat moss peat. Our findings suggest that within about 17 years after fen restoration, and thereby a water table rise close to surface, TOC of the near-surface peats increased to values that are typical for undisturbed peatlands. This indicates that restoration can lead to the re-establishment of peatlands as potential carbon sinks, with TOC within the near-surface peat as one key factor in this process. Further, we assume that the decrease in nutrient availability, decrease of BD, and new, undisturbed peat layers can favor the establishment of mire-specific biodiversity and support ecosystem services similar to near-natural mires. [ABSTRACT FROM AUTHOR]

In response to the environmental concerns posed by cadmium (Cd) contamination, the application of nano‐submicron mineral‐based soil conditioner (MSC) as a potential soil amendment has garnered interest due to its promising Cd mitigation properties. In this study, we aimed to investigate the solidification capacity and mechanism of Cd in MSC and examine the phase and morphology changes following solidification. Systematic experiments were conducted to assess the solidification capacity of MSC for Cd, revealing an impressive efficiency of nearly 100 % even at Cd concentrations of approximately 800 mg/L. The solidification efficiency was found to be positively correlated with the pH value, significantly declining as the environment shifted from pH>7 to pH<7. Notably, under alkaline conditions (pH>7), Cd solidification in MSC was primarily attributed to the Cd‐OH complex formed on the surface of MSC and aided by cation‐exchange reaction. In contrast, under acidic conditions (pH<7) and exposure to extreme Cd concentrations, Cd(OH)Cl precipitation became the dominant mechanism for solidification. Interestingly, the presence of KCdCl3, a water‐soluble phase, did not significantly contribute to the overall solidification efficiency. These findings provide valuable insights into the solidification mechanism of Cd in MSC and offer potential implications for soil remediation efforts targeting Cd contamination. [ABSTRACT FROM AUTHOR]

Soil fertility's significance in agriculture profoundly affects the well-being of farmers. A novel technique is being introduced to gauge soil categorization levels, based on soil chemical data involving elements like "Nitrogen, Phosphorus, Potassium, PH value, Organic Carbon, Electrical Conductivity, Sulphur, Zinc, iron", and more. Classification and regression methodologies are employed to predict soil categorization levels like low level, medium, and high level. The dataset for soil categorization analysis was collected from a farm within the Bhandara region of Maharashtra. The ultimate model's efficacy was ascertained through a combination of soil analysis and meticulous refinement of hyper parameters in both random forest classification and regression approaches. In pursuit of an improved model, various alternative strategies for classification and regression were explored. Evaluation metrics, including OOB error rate, AUC accuracy, error rate, recall, precision, and F-score, were applied in the classification analysis. For the regression aspect, metrics such as mean squared error, r2 score, and error rate were employed. After subjecting the experimental dataset to thorough analysis using the random forest algorithm, accurate predictions of soil fertility levels were achieved with 93% accuracy of training and 83% accuracy of testing. This method offers a reliable pathway to enhance crop productivity. [ABSTRACT FROM AUTHOR]

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Copyright of Food Research & Development is the property of Food Research & Development Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The effect of the pH of precursor solution on the microstructure as well as the magnetic properties of Cu0.2Co0.8Fe2O4 nanoferrite samples, was investigated. The structures of the samples analyzed by X-ray diffraction were all in the cubic spinel phase. The average crystallite size of the samples was obtained by Scherrer's formula to be between 60 and 68 nm, indicating that there is some effect of pH. The cation distribution proves that there is a difference in the ion spacing of the samples synthesized at different pH values. FTIR spectroscopy again verified the spinel structure of the synthesized samples and the absorption peaks were shifted due to the redistribution of cations in the samples at different pH values. Scanning electron microscopy observed that the particle size of the samples gradually decreased with increasing pH, but all were cubic with some degree of agglomeration due to magnetic properties. Elemental analysis yielded a pure phase structure for the samples. The samples are ferromagnetic as can be seen from the hysteresis lines of the samples. The magnetic parameters of the synthesized samples are all maximum at pH = 10, such as residual magnetization strength (Mr = 24.31 emu/g), saturation magnetization strength (Ms = 57.41 emu/g), coercivity (Hc = 751.41 Oe), and so on. The samples can be used in the field of magnetic recording. Highlights: This article uses the sol-gel method which can significantly save time and energy consumption and requires a lower sintering temperature, compared to traditional methods. The prepared samples were characterized using XRD, FTIR, SEM, EDX, and VSM. The experimental results show that the Cu0.2Co0.8Fe2O4 nano ferrite samples have good structural and magnetic stability. When pH = 10, the magnetic parameters of the synthesized samples are the maximum. This means that these samples can be used in the field of magnetic recording. [ABSTRACT FROM AUTHOR]

Background: The association between pH values and outcome for patients after out-of-hospital cardiac arrest (OHCA) was not fully elucidated; besides, the relationship of change in pH values and neurological outcome was unknown. The aim was to explore the association of pH values as well as change in pH values and neurological outcome for OHCA cardiac patients. Methods: The adult patients with non-traumatic out-of-hospital cardiac arrest, shock-refractory ventricular fibrillation or pulseless ventricular tachycardia, and at least two arterial blood gases analysis recorded after admission were included. The change in pH values is calculated as the difference between the second and first pH value, and divided by time interval got the rate of change in pH values. The primary outcome was modified Rankin Score (mRS), dichotomized to good (mRS 0–3) and poor (mRS 4–6) outcomes at hospital discharge. The independent relationship of the first pH value, second pH value, and changes in pH values with neurological outcome was investigated with multivariable logistic regression models, respectively. Results: A total of 1388 adult patients were included for analysis, of which 514 (37%) had good neurological outcome. The median first pH value and second pH value after admission were 7.21 (interquartile range [IQR] 7.09–7.29) and 7.28 (IQR 7.20–7.36), respectively. The median absolute, relative change, and rate of changes in pH values were 0.08 (IQR 0.01–0.16), 1.10% (IQR 0.11–2.22%), and 0.02 (IQR 0–0.06) per hour, respectively. After adjusting for confounders, the higher first pH value (odds ratio [OR] 3.81, confidence interval [CI] 1.60–9.24, P = 0.003) and higher second pH value (OR 9.54, CI 3.45–26.87, P < 0.001) after admission were associated with good neurological outcome, respectively. The absolute (OR 1.58, CI 0.58–4.30, P = 0.368) and relative (OR 1.03, CI 0.96–1.11, P = 0.399) change as well as the rate of change (OR 0.98, CI 0.33–2.71, P = 974) in pH values were not associated with neurological outcome. Conclusions: For OHCA patients, abnormality in pH values was very common, with a more acidic pH value indicating poor neurological outcome. However, the change in pH values was not associated with outcomes.

This is an article in the field of environmental engineering. In order to study the effect of kaolin on the adsorption performance of wastewater containing Cu2+ and Pb2+, experiments on the adsorption of heavy metal ions by kaolin under different initial concentrations, temperatures, adsorption time, kaolin content and pH values are carried out. And analyzed the results of Cu2+ and Pb2+ co-adsorption test by kaolin. The results show that the adsorption effect of kaolin on metal Pb2+ ions is better than the adsorption effect of kaolin on metal Cu2+ ions. Combining the test results and economic benefits, when the initial concentration is 200 mg/L, the pH is 6, the temperature is 30 °C, the kaolin content is 1.5 g, and the adsorption time is 2.0 h, Kaolin has the best adsorption effect on metal Pb2+ and Cu2+ ions. The adsorption capacity of metal Pb2+ ions reached 56.38, 56.22, 58.76, 35.75, and 42.42 mg/g, respectively. The adsorption capacity of metallic Cu2+ ions is 45.99, 47.45, 47.27, 25.26, 22.52 mg/g. On the whole, the adsorption capacity of kaolin for co-adsorbed metal ions (Cu2+, Pb2+) is smaller than that of a single ion. This is because two metal ions will affect each other's adsorption process during the adsorption process. The fit of Langmuir model to the test curve is much higher than the fit of Freundlich model to the test curve. This shows that the Langmuir isotherm adsorption model is more suitable for the change law of the amount of metal ions adsorbed by kaolin. Furthermore, it is proved that the adsorption of heavy metal ions by kaolin belongs to surface adsorption, and the adsorbed heavy metal ions exist independently of each other.

Abstract Background Cervical cancer is the fourth most common cancer among women, with persistent high-risk human papillomavirus (HPV) infection being responsible for its progression. In healthy, pre-menopausal women, the vaginal pH value is maintained at 3.8–4.5, but various factors can affect it. Previous studies have suggested the relationship between vaginal pH value and HPV infection. In this study, we aimed to explore the relationship between vaginal pH and susceptibility of HPV infection. Methods In our study, we retrospectively collected medical information from women who underwent leukorrhea examination at our hospital. We excluded women with infectious diseases or cancer, those who were pregnant or within 6 months post-delivery, and those without HPV test results within 6 months. The association between percentage of HPV infection and vaginal pH value was analyzed. Furthermore, we prepared HPV pseudovirus (PsVs) by co-transfecting structure plasmids and report plasmids in 293FT cells. In vitro, we changed the pH value of cell culture medium to investigate its influence on HPV PsVs infection. In vivo, we changed mouse’s vaginal pH value to investigate its influence on HPV PsVs infection. Results Our retrospective study included 3115 women aged 20–78, including 2531 women with HPV negative and 584 women with HPV positive. The percentages of both HPV infection and high-risk HPV infection were higher in women with a vaginal pH value ≥5.0 compared to those with a pH value