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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]

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.)

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】 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.

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]

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.)

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.)

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]

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 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]

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]

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

This study investigates the pH values and optical characteristics of Dual Rinse HEDP, either independently or combined with sodium hypochlorite (NaOCl), and compares them to other irrigants used in endodontics. The solutions used in this study were commercially acquired and prepared, followed by pH measurements using a pH meter and spectral analysis using UV/Vis spectrophotometry in specified wavelengths of the ultraviolet (UV) C (190–280 nm), UVB (281–315 nm), UVA (316–400 nm), visible light (VL) (401–780 nm), and near-infrared (NIR) spectra (781–1100 nm). The pH analysis revealed alkaline values for NaOCl, EDTA, Dual Rinse HEDP, and the HEDP + NaOCl combination, an acidic value for citric acid, and nearly neutral values for chlorhexidine and distilled water. Spectral analysis revealed the notable absorption characteristics of endodontic irrigants. In the UV range, all solutions exhibited higher absorption values to water (p < 0.05), with Dual Rinse HEDP resembling EDTA and citric acid, and HEDP + NaOCl resembling NaOCl. The NIR region highlights absorption peaks around 975 nm for all solutions, including NaOCl and Dual Rinse HEDP + NaOCl, suggesting potential applications in laser-activated irrigation. This study provides comprehensive insights into the pH and optical features of endodontic irrigants, emphasizing their potential roles in enhancing disinfection strategies and optimizing laser-activated irrigation protocols. [ABSTRACT FROM AUTHOR]

Surfaee hygiene is eommonly measured as a part of the quality system of food proeessing plants but as the baeteria present are eommonly not identified and their roles for food quality and safety are not known. Here, we review the identity of residential baeteria and eharaeteristies relevant for survival and growth in the food industry along with potential implieations for food safety and quality. Sampling after eleaning and disinfeetion inereases the likelihood of targeting residential baeteria. The inereasing use of sequeneing teehnologies to identify baeteria has improved knowledge about the baeteria present in food premises. Overall, non-pathogenie gram-negative baeteria, espeeially Pseudomonas spp., followed by Enterobacteriaceae and Acinetobacter spp. dominate on food proeessing surfaees. Pseudomonas spp. persistenee is likely due to growth at low temperatures, biofilm formation, toleranee to bioeides and low growth requirements. Gram-positive baeteria are most frequently found in dairies and in dry produetion environments. The residential baeteria may end up in the final produets through eross eontamination and may affeet food quality. Sueh effeets ean be negative and lead to spoilage, but the baeteria may also eontribute positively, as through spontaneous fermentation. Pathogenie baeteria present in food proeessing environments may interaet with residential baeteria, resulting in both inhibitory and stimulatory effeets on pathogens in multi speeies biofilms. The residential baeterial population or baeteriota, whieh does not seem to be an important source for the transfer of antibiotie resistanee genes to humans but more knowledge is needed to verify this. If residential baeteria oeeur in high numbers, they may influenee proeesses sueh as membrane filtration and eorrosion. The use of high temperatures to preserve and ensure the safety of food is based on the effeet of mierobial destruetion. Thermal proeessing is one of the most widely used unit operations employed in the food industry and is frequeney determined as a eritieal eontrol point. This white paper eovers the main seienee behind the unit operation and should be used to underpin the development and design of thermal proeessing steps type. [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.)

In order to find a general corrosive treatment scheme suitable for underground structures in Foshan area, based on the geotechnical investigation of the Phase I project of Foshan Metro Line 4, this study adopted the method of literature research and comparative analysis of specifications to conduct in-depth analysis of the corrosion resistance requirements in different specifications. Furthermore, the existing problems in the GB/T 50476-2019 Durability Design Standard for Concrete Structures were discussed, and combined with the actual situation of the existing Foshan Metro Line 3 and Guangzhou Metro Line 7 West Extension to Shunde section, a set of groundwater corrosion prevention and control design standards suitable for subway structures in Foshan area were carried out. The application results in the early construction site of Foshan Metro Line 4 show that when executed according to the above design standards, the relevant performance indicators meet the regulatory requirements. [ABSTRACT FROM AUTHOR]

In bioprocesses, the pH value is a critical process parameter that requires monitoring and control. For pH monitoring, potentiometric methods such as pH electrodes are state of the art. However, they are invasive and show measurement value drift. Spectroscopic pH monitoring is a non-invasive alternative to potentiometric methods avoiding this measurement value drift. In this study, we developed the Good pH probe, which is an approach for spectroscopic pH monitoring in bioprocesses with an effective working range between pH 6 and pH 8 that does not require the estimation of activity coefficients. The Good pH probe combines for the first time the Good buffer 3-(N-morpholino)propanesulfonic acid (MOPS) as pH indicator with Raman spectroscopy as spectroscopic technique, and Indirect Hard Modeling (IHM) for the spectral evaluation. During a detailed characterization, we proved that the Good pH probe is reversible, exhibits no temperature dependence between 15 and 40 °C, has low sensitivity to the ionic strength up to 1100 mM, and is applicable in more complex systems, in which other components significantly superimpose the spectral features of MOPS. Finally, the Good pH probe was successfully used for non-invasive pH in-line monitoring during an industrially relevant enzyme-catalyzed reaction with a root mean square error of prediction (RMSEP) of 0.04 pH levels. Thus, the Good pH probe extends the list of critical process parameters monitorable using Raman spectroscopy and IHM by the pH value. [ABSTRACT FROM AUTHOR]

AZ80 magnesium alloy was surface treated by micro‐arc oxidation (MAO) and composite of laser shock penning (LSP) and MAO techniques. Untreated and treated specimens were pre‐corroded in simulated body fluids (SBF) with different pH values (pH 4, 7.4, and 9). The ratcheting behavior of all test specimens was experimentally investigated under stress‐controlled loading. The positive or negative value of the ratcheting strain reflects the mechanism of cyclic deformation. The ratcheting strain with negative values is associated with the cyclic deformation being dominated by twinning–detwinning, while the ratcheting strain with positive values is due to dislocation slip playing a dominant role in the cyclic deformation. A higher absolute value of the ratcheting strain means a lower the ratcheting life. Single MAO coating is not conducive to the fatigue life of magnesium alloy in acidic SBF environment, while LSP/MAO composite coating can improve the fatigue life of magnesium alloy under various loading conditions and different pH environment. Highlights: Two modified layers were prepared on the surface of AZ80 magnesium alloys.Modified layers and pH values on effect of ratcheting deformation was investigated.Four deformation mechanisms were used to evaluate the ratcheting behavior. [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.

Stem cell-based myocardial regeneration is a frontier topic in the treatment of myocardial infarction. Manipulating the metabolic microenvironment of stem cells can influence their differentiation into cardiomyocytes, which have promising clinical applications. pH is an important indicator of the metabolic environment during cardiomyocyte development. And lactate, as one of the main acidic metabolites, is a major regulator of the acidic metabolic environment during early cardiomyocyte development. Here, we summarize the progress of research into the influence of pH value and lactate on cardiomyocyte survival and differentiation, as well as related mechanisms.

Probiotic starters are a biological product based on lactic acid bacteria. Their metabolic characteristics determine the properties of the final products. This study evaluated the bacterial composition of a starter culture at various time intervals during the fermentation of a probiotic dairy product. The starter consisted of Streptococcus salivarius ssp. thermophiles, Lactobacillus delbrueckii ssp. bulgaricus, Bifidobacterium bifidum, Bifidobactreium animalis ssp. lactis, Bifidobacterium longum, Lactobacillus acidophilus, and Lacticaseibacillus casei. Pasteurized milk served as the object of fermentation. The starter culture was activated in sterilized skimmed milk. Sampling occurred throughout the entire fermentation process (0, 3, 6, 9, 12, 15, and 18 h). To determine the microbiome of the substrates, the authors used the next-generation high-throughput sequencing that targeted V3 of 16S rRNA gene. The fermentation resulted in a decrease in Bifidobacterium and an increase in Lactobacillus, which peaked (97.5%) after 15 h of fermentation. Each sampling showed that the count of Streptococcus went down. Eventually, Lactobacillus replaced all other genera, including Bifidobacterium, probably, as a result of pH going down during fermentation. The optimal values for the proliferation of Lactobacillus (pH = 4.2–4.4), which were registered after 18 h, turned out to be too low for the productive growth of Bifidobacterium. The research demonstrated the changes in the bacterial composition of the dairy base during fermentation. The high-throughput sequencing proved to be an efficient tool in controlling probiotic fermentation processes.

In order to study the effect of extraction pH on gelling properties and characteristic peptide identification of pigskin gelatin, the molecular mass distribution and gelling properties of pigskin gelatin extracted under different pH conditions were studied by dodecyl sodium sulfate-polyacrylamide gel electrophoresis (SDS-PAGE), a texture analyzer and a rheometer. Moreover, the characteristic peptides were identified by high performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS). The results showed that with a decrease in pH, the relative molecular mass of pigskin gelatin initially increased and then decreased, the gel intensity gradually declined, and the gel melting temperature and gelling temperature initial increased and then decreased. Gelatin extracted at pH 1 had the worst gelling properties. HPLC-MS/MS analysis showed that pH significantly affected the traceability of gelatin. In this study, 62, 71, 79 and 76 characteristic peptides were detected from pigskin gelatins extracted at pH 1, 3, 5 and 7, respectively. Among them, 37 characteristic peptides were common to all pigskin gelatins. Compared with our previous research, 17 characteristic peptides were found to be common to pigskin gelatins extracted under different conditions. These stable common characteristic peptides could be used as an important basis for pigskin gelatin traceability with high accuracy.

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 (RP2), 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 (RP2) 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.

Objective: This study aimed to examine the potential for probiotics in fruit waste from traditional markets in Semarang City in terms of chemical and microbiological qualities. Materials and Methods: The study used two designs: a completely randomized design with four treatments and four replications. Result: The research on mapping the potential of fruit waste originating from various traditional markets in Semarang City based on different market activities affected the potential hydrogen (pH) value, lactic acid bacteria (LAB), total bacteria, and total fungi of fruit waste, while carbo¬hydrate, protein, fat, and fiber content were not affected. Identification of fruit waste as a fer¬mentation starter affected the pH value, total acidity, total LAB, total bacteria, total fungi, and Salmonella, while Escherichia coli was not affected. Waste from supplier market activities yielded a better pH, better chemical and microbiological content, and contained carbohydrates, protein, fat, and fiber of 59.83, 3.53, 2.67, and 4.94 gm/100 gm. Conclusion: The best fermentation time for fruit wastage was four days, which had a pH value of 2.85, total acid of 0.90%, total LAB, total bacteria, and total fungi of 4.00. 6.33, and 3.00 log colony-forming unit/gm, and no pathogenic bacteria, Salmonella or E. coli. Fruit waste could be used as probiotics, with fermentation processing for four days to improve the chemical and micro¬biological quality of the waste. [Vet. Res. Notes 2023; 3(8.000): 63-68]

This study explored the change law changing pattern of pH value of steel slag leaching solution in the process of steel slag dissolution with an aim to study the influence of steel slag on environment.Specifically, it analyzed the influence law of steel slag basicity, magnesium oxide content, water temperature, steel slag particle size, liquid-solid ratio and other factors on pH value of steel slag leaching solution and conducted a comparative test with on-site steel slag.Results show that the pH value of the leaching solution after steel slag dissolution is in the range of 10~12, and with the change of time, the pH value first increases and then decreases.Increasing the basicity of steel slag and the content of magnesium oxide can increase the pH value of the leaching solution.The increase of water temperature, steel slag size and liquid-solid ratio can reduce the pH value of the leaching solution.

For improving the corrosion resistance of 904L stainless steel under high Cl- concentration environment with different pH values condition，the corrosion behavior of 904L austenitic stainless steel in 100 g/L NaCl solution at different pH values was studied by cyclic polarization curves，electrochemical impedance spectroscopy，Olympus confocal microscopy，scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS).Results showed that the corrosion resistance of 904L stainless steel increased with the increase of pH value，EIS consisted of two capacitive reactance arcs，and the radius of capacitive reactance arc increased with the increase of pH value，and the capacitive reactances were all in the same order of magnitude.Meanwhile，lower pH value conditions could enhance the destructive effect of Cl- on the passive film.With the decrease of pH value，the range of passive region of the material decreased.When the pH＝2，slight pitting occurred on the surface of the material.

The high alkaline condition of concrete naturally protects embedded steel bars from corrosion by forming a passive protective film. The pH of concrete is generally high, but concrete with different mix compositions may have various pH values. The pH of concrete may decrease over time due to long-term mechanical, chemical, biological and physical factors. Therefore, monitoring the pH value of concrete is crucial to checking if its alkalinity is within an acceptable range and ensuring that the concrete structure is in good health condition. However, the pH measurement for cement-based materials is not standardised. Ex-situ leaching, one of the recommended methods for pH measurement, is simple and practical. In this method, the sample will be crushed, leached and tested using a pH electrode probe. The lifespan of the pH electrode probe may decrease due to the existing suspended particles in the solution. Therefore, one recommendation is to filter the solution before using the probe. In this study, the effect of different filtering setups on the pH value of a cement mortar with a cement-to-sand ratio of 1:3 was evaluated. pH test results showed that filtering can produce similar outcomes to those without filtering, regardless of the type of filter paper and its pore size. However, filtering is strongly recommended for electrode protection of the pH meter. As an innovative filtering setup for cement-based materials, syringe filtering was introduced in this study because it is more economical and its operation is simpler compared to the other methods.

When exposed to corrosive environments, metals, which are relatively common industrial materials, undergo serious corrosion, leading to significant economic losses. Therefore, studying the corrosion rate of metals in their early stages holds great pedagogical significance. This study employs a standard specimen of 20# steel as an experimental object, designing the experimental teaching of metal corrosion rate under varying temperatures, PH levels, and hydrated salt materials. The weightlessness method determines the overall corrosion rate of the metal, while the electrochemical method determines the localized corrosion rate of the metal. When the experimental temperature is 80℃ and 100℃, the corrosion rate of 20# steel is the largest; both are 0.00800g·m−2·d−1, and the charge transfer resistance increases gradually when the temperature is −20℃~5℃, and decreases gradually when the temperature is 5℃~100℃. The corrosion rate of the metal did not change much at pH=7 and 8, and the corrosion rate reached 0.688 mm/a, and the impedance curve polarization resistance Rp was the smallest when pH=5, and its corrosion resistance was poor under acidic conditions. The average corrosion rates in MgSO4·7H2O, and CaCl2·6H2O and Ba(OH)2·8H2O were 0.0030g/m−2h−1, 0.0018g/m−2h−1, and 0.0050 g/m−2h−1, respectively. Teaching experiments were used to carry out the present study. The study aims to let students experience the process of metal corrosion through teaching experiments and better help them solve cognitive difficulties in metal corrosion.

We studied a mesotrophic swamp drained 25 years ago in the northern part of the Ob' River basin (56°23′710″ N, 84°34′043″ E). In peat soils (0–30 cm layer), the weighted average of peroxidase activity for the season (base level) constituted 14.4, 21.9, and 70 units (mL I/g abs. dry soil per 2 min) in the areas subjected to weak, moderate, and intensive drainage, respectively. Second-order parabola is the most adequate function of the main trend of development of seasonal fluctuations in peroxidase activity. Numerical values and signs of the parabolic trend parameters showed that the average peroxidase activity decreased from June to October weekly by 4.4, 7.6 and 15.2 units with weekly average acceleration by 0.31, 0.59 and 1.54 units in the mode of weak, moderate, and intensive drainage, respectively. The seasonal wave of peroxidase activity relative to the baseline level was characterized by a June increase in growth rates with a maximum in the layer of 0–10 cm. In July, there was a decrease in the growth rate according to the depth of reclamation: in the modes of weak and moderate drainage, the process embraced the entire soil profile in August; in case of intensive drainage, in October. The enzyme activity significantly and positively correlated with the soil volumetric water content and pH, negatively correlated with redox potential, and displayed multidirectional relationship with the soil temperature. Environmental conditions acted as mutually replacing parameters when assessing their contribution to the seasonal dynamics of peroxidase, creating the effect of interchangeability of environmental gradients. Canonical determination indices approximated the cumulative impact of the discussed set by 52–74%, depending on the depth of reclamation. Canonical weights showed that the hydrothermal regime was the main factor, regulating the seasonal activity of peroxidase: according to canonical correlations, temperature was the main factor under the conditions of weak drainage, moisture was the main factor under the conditions of intensive drainage, and both moisture and temperature were important factors under the conditions of moderate drainage. The peroxidase activity and the depth of humification in peat soils of different degrees of drainage were interrelated in 87% of cases. [ABSTRACT FROM AUTHOR]

Aim: The goal of the study is to evaluate and compare the pH and dimensional stability of the experimental root sealer to those of existing root sealers commonly used in endodontic therapy. Methods: The study samples were produced using commercially available sealers as well as experimental sealers containing nanoparticles. The pH was measured using a digital pH meter (accuracy of 0.01). Before each pH measurement, the pH meter's accuracy was calibrated with a solution. Once the relevant dimension samples were generated, the dimensional stability of the materials was evaluated. L 30 - L/L × 100 was the formula used to calculate the percentage of dimensional change. Results: The Apexit Plus demonstrated a 1.33% expansion compared to the experimental sealer's 0.43%. The contraction was 0.37% for AH Plus. The mean pH of the experimental root canal sealer utilized at various periods of immediate, 24 h and 1 week after is 9.51, 8.48, and 8.17. The mean pH of the AH Plus root canal sealer immediately, 24 h and 1 week was 8.30, 7.70, and 6.80, respectively. Conclusion: Within the constraints of the studies, the experimental sealer had stronger pH and dimensional stability than commercially available sealers. In vivo studies can be performed to reassess the qualities. [ABSTRACT FROM AUTHOR]

Copyright of Shipin Kexue/ Food Science is the property of Food Science 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.)