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This study employed machine learning, specifically deep neural networks (DNNs) and long short-term memory (LSTM) networks, to build a model for estimating acid rain pH levels. The Yangming monitoring station in the Taipei metropolitan area was selected as the research site. Based on pollutant sources from the air mass back trajectory (AMBT) of the HY-SPLIT model, three possible source regions were identified: mainland China and the Japanese islands under the northeast monsoon system (Region C), the Philippines and Indochina Peninsula under the southwest monsoon system (Region R), and the Pacific Ocean under the western Pacific high-pressure system (Region S). Data for these regions were used to build the ANN_AMBT model. The AMBT model provided air mass origin information at different altitudes, leading to models for 50 m, 500 m, and 1000 m (ANN_AMBT_50m, ANN_AMBT_500m, and ANN_AMBT_1000m, respectively). Additionally, an ANN model based only on ground station attributes, without AMBT information (LSTM_No_AMBT), served as a benchmark. Due to the northeast monsoon, Taiwan is prone to severe acid rain events in winter, often carrying external pollutants. Results from these events showed that the LSTM_AMBT_500m model achieved the highest percentages of model improvement rate (MIR), ranging from 17.96% to 36.53% (average 27.92%), followed by the LSTM_AMBT_50m model (MIR 12.94% to 26.42%, average 21.70%), while the LSTM_AMBT_1000m model had the lowest MIR (2.64% to 12.26%, average 6.79%). These findings indicate that the LSTM_AMBT_50m and LSTM_AMBT_500m models better capture pH variation trends, reduce prediction errors, and improve accuracy in forecasting pH levels during severe acid rain events. [ABSTRACT FROM AUTHOR]

Recognising the fact that the SARS-CoV-2 spike glycoprotein is the most crucial protein for the virus's attachment to surfaces and subsequent infection, we carried out massive all-atom molecular dynamics studies of the conformational states of S-protein in solvents of various pH values, ranging from pH = 1 through pH = 11. Our studies found that: (1) The S-protein's structural deviation measured in the backbone at pH = 1 is 185% higher than that of pH = 7, and most of this overall deviation occurs at the receptor-binding domain and N-terminal domain. (2) Structural changes are also observed at both pH = 3 and pH = 11, albeit to a lesser extent than at pH = 1. (3) Changes, as measured by various metrics at pH = 5, pH = 7 and pH = 9, are insignificant. Such a high degree of structural tolerance of the S-protein at these pH values corroborates indirectly with in vitro observations that the virus retains significant infectivity over a wide range of pH. The multiscale structural analyses pinpoint the critical regions that are responsible for the S-protein's structural deviations. [ABSTRACT FROM AUTHOR]

The formation and colonization of biofilms inside the oral cavity are still not understood in detail, although biofilms inside the oral cavity can lead to expensive dental diseases like caries, periodontitis, or the detachment of implants. Such biofilms consist, to a large extent, of proteins, carbohydrates, and other macromolecules. Whereas the interaction of proteins with dental materials is widely studied, the literature does not report interactions of polysaccharides. Here, scanning force spectroscopy is used to investigate the adhesion forces of dextran as an abundant polysaccharide on different dental materials. The focus is dental titanium, accompanied by comparisons with dental gold and silicon as reference material. Different pH values and dental materials mimic representative conditions in the oral cavity. The main finding is that dextran adheres very well to dental materials, but with lower adhesion forces than proteins of similar mass, such as bovine serum albumin. As proteins, the adhesion forces increase with the contact time until a plateau is reached and the forces differ with the dental material. However, in contrast to proteins, pH does not play a role because dextran is uncharged over the measured range between pH 4.5 and pH 13. [ABSTRACT FROM AUTHOR]

This study primarily investigates the effect of fly ash (FA) content on the mechanical properties and hydration performance of alkali-activated ground granulated blast furnace slag cement (AAGC) and compares the related properties with ordinary Portland cement (OPC). Additionally, we examined the hydration products; performed thermal analysis, MIP, and SEM; and determined chemically bound water and pH values of AAGC. The compressive strength of AAGC showed a retrogression phenomenon from 3 to 28 days, with the 14-day and 28-day compressive strengths of AAGC being higher than those of OPC. The AAGC with 20% FA content exhibited the highest 28-day compressive strength (75 MPa). The hydration heat release rate curve of OPC and AAGC was divided into the initial induction period, induction period, acceleration period, deceleration period, and steady period. As FA content increased, the 28-day pore volume of AAGC increased, while pH values and chemically bound water decreased. SEM images of AAGC with low FA content showed more microcracks. [ABSTRACT FROM AUTHOR]

Copyright of Acta Petrologica et Mineralogica / Yanshi Kuangwuxue Zazhi is the property of Acta Petrologica et Mineralogica 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 this study, Fe3O4/Ag magnetite-silver (MSx) nanocomposites were investigated as catalysts for advanced oxidation processes by coupling the plasmonic effect of silver nanoparticles and the ferromagnetism of iron oxide species. A surfactant-free co-precipitation synthesis method yielded pure Fe3O4 magnetite and four types of MSx nanocomposites. Their characterisation included structural, compositional, morphological and optical analyses, revealing Fe3O4 magnetite and Ag silver phases with particle sizes ranging from 15 to 40 nm, increasing with the silver content. The heterostructures with silver reduced magnetite particle aggregation, as confirmed by dynamic light scattering. The UV–Vis spectra showed that the Fe:Ag ratio strongly influenced the absorbance, with a strong absorption band around 400 nm due to the silver phase. The oxidation kinetics of organic pollutants, monitored by in situ luminescence measurements using rhodamine B as a model system, demonstrated the higher performance of the developed catalysts with increasing Ag content. The specific surface area measurements highlighted the importance of active sites in the synergistic catalytic activity of Fe3O4/Ag nanocomposites in the photo-Fenton reaction. Finally, the straightforward fabrication of diverse Fe3O4/Ag heterostructures combining magnetism and plasmonic effects opens up promising possibilities for heterogeneous catalysis and environmental remediation. [ABSTRACT FROM AUTHOR]

Lakes and reservoirs are an important sources of drinking water for human life. However, numerous water quality indexes show seasonal fluctuation under different climatic conditions. We conducted a one-year investigation of Taiping Lake in year 2022 to construct relationship between water quality parameters and water quality. High water temperature promotes the growth of algae, and the existence of N species could provide the essential nutrient substance for the growing of algae. Under the irradiation of sunlight, algae will consume carbon dioxide through photosynthesis and release oxygen which can raise oxygen levels in the water. However, the rapid growth of algae could influence the acid-base balance in water through the consumption of carbon dioxide; thus, resulting in the increasing of pH values. These pH changes may pose a threat to drinking water.

• An analytical protocol was developed to study water extracts from aged lacquer. • 12 New compounds were identified as aging products of lacquer. • During aging, pH, conductivity, and peak areas and indices of components changed. • Iron treatment caused the most changes in water extract while drying oil the least. Lacquered artifacts are among the most exquisite objects in museum collections. However, during aging, a considerable quantity of water-soluble products are formed on the lacquered surfaces, posing significant conservation and preservation challenges. This paper presents in-depth research on the composition of these water-soluble products by the investigation into water extracts from Asian lacquer coatings during artificial aging. Lacquer coatings of 15 specially designed formulations involving different lacquer tree saps (urushi, laccol, and thitsi), drying oils, tree resins and pigments were produced and artificially aged. A set of analytical methods was developed including pH and conductivity measurements, and peak area and index analyses based on gas chromatography–mass spectrometry (GC–MS). Results show that artificial light aging cause the formation of a complex array of hydroxyl carboxyl benzenes (Webboxy products), while simultaneously decreasing the amounts of saturated straight-chain dicarboxylic fatty acids and glycerol. Distinct changes in the average number of hydroxyls and carboxyls bonded to the benzene rings or average chain length of the dicarboxylic fatty acids have also been observed with light aging. The additive that impeded light degradation and formation of water-soluble products the most is drying oil, and the additives that accelerated composition changes of water-soluble products was iron (treatment). Additionally, 12 new compounds have been identified as aging products of lacquer, such as tetramethyl dimethoxybenzene tetracarboxylate and benzene hexacarboxylic acid hexamethyl ester. The understanding of pH and conductivity readings of water extracts from aged lacquer is significantly improved. The research results contribute to the knowledge of aging pathways and mechanisms of alteration to Asian lacquer coatings. [Display omitted] [ABSTRACT FROM AUTHOR]

In the present work, the photodegradation of Rhodamine B with different pH values by using Bi2O3 microrods under visible-light irradiation was studied in terms of the dye degradation efficiency, active species, degradation mechanism, and degradation pathway. X-ray diffractometry, polarized optical microscopy, scanning electron microscopy, fluorescence spectrophotometry, diffuse reflectance spectra, Brunauer–Emmett–Teller, X-ray photoelectron spectroscopy, Fourier-transform infrared spectroscopy, UV–visible spectrophotometry, total organic carbon, and liquid chromatography–mass spectroscopy analysis techniques were used to analyze the crystal structure, morphology, surface structures, band gap values, catalytic performance, and mechanistic pathway. The photoluminescence spectra and diffuse reflectance spectrum (the band gap values of the Bi2O3 microrods are 2.79 eV) reveals that the absorption spectrum extended to the visible region, which resulted in a high separation and low recombination rate of electron–hole pairs. The photodegradation results of Bi2O3 clearly indicated that Rhodamine B dye had removal efficiencies of about 97.2%, 90.6%, and 50.2% within 120 min at the pH values of 3.0, 5.0, and 7.0, respectively. In addition, the mineralization of RhB was evaluated by measuring the effect of Bi2O3 on chemical oxygen demand and total organic carbon at the pH value of 3.0. At the same time, quenching experiments were carried out to understand the core reaction species involved in the photodegradation of Rhodamine B solution at different pH values. The results of X-ray photoelectron spectroscopy, Fourier-transform infrared spectroscopy, and X-ray diffractometer analysis of pre- and post-Bi2O3 degradation showed that BiOCl was formed on the surface of Bi2O3, and a BiOCl/Bi2O3 heterojunction was formed after acid photocatalytic degradation. Furthermore, the catalytic degradation of active substances and the possible mechanism of the photocatalytic degradation of Rhodamine B over Bi2O3 at different pH values were analyzed based on the results of X-ray diffractometry, radical capture, Fourier-transform infrared spectroscopy, total organic carbon analysis, and X-ray photoelectron spectroscopy. The degradation intermediates of Rhodamine B with the Bi2O3 photocatalyst in visible light were also identified with the assistance of liquid chromatography–mass spectroscopy. [ABSTRACT FROM AUTHOR]

Background: Minced meat is a valuable source of nutrients, but it is vulnerable to contamination by microorganisms commonly present in the environment. Additionally, there is a risk of adulteration with cheaper meat sources, which can be harmful to consumers. Aim: It is crucial to identify meat adulteration with distinct microbiological analysis for legal, economic, religious, and public health purposes. Methods: A total of 100 minced meat samples were collected from several markets in Sharkia Governorate, Egypt. These samples were then subjected to bacteriological testing and an advanced multiplex PCR method. This method enables the detection of bovine, equine, porcine, and dog species in meat samples with just one step. Results: The adulterated samples had a higher total bacterial count and pH values compared to pure bovine meat. These differences in bacterial count and pH values were statistically significant, with p-values of 0.843 (log10) and 0.233, respectively. The frequency of E. coli occurrence was 13%, and the O111 serotype was predominant in the adulterated samples. Listeria monocytogenes and S. aureus were isolated with prevalence rates of 3% and 29%, respectively. Besides, the SYBR-green multiplex real-time PCR assay used in this study detected adulteration with dog, equine, and porcine meats in the examined samples at rates of 9%, 5%, and 4%, respectively. Conclusion: This method provides a sensitive and specific approach to detect issues related to well-being and safety. [Open Vet J 2024; 14(1.000): 389-397]

This study primarily investigates the effect of fly ash (FA) content on the mechanical properties and hydration performance of alkali-activated ground granulated blast furnace slag cement (AAGC) and compares the related properties with ordinary Portland cement (OPC). Additionally, we examined the hydration products; performed thermal analysis, MIP, and SEM; and determined chemically bound water and pH values of AAGC. The compressive strength of AAGC showed a retrogression phenomenon from 3 to 28 days, with the 14-day and 28-day compressive strengths of AAGC being higher than those of OPC. The AAGC with 20% FA content exhibited the highest 28-day compressive strength (75 MPa). The hydration heat release rate curve of OPC and AAGC was divided into the initial induction period, induction period, acceleration period, deceleration period, and steady period. As FA content increased, the 28-day pore volume of AAGC increased, while pH values and chemically bound water decreased. SEM images of AAGC with low FA content showed more microcracks.

Background: Minced meat is a valuable source of nutrients, but it is vulnerable to contamination by microorganisms commonly present in the environment. In addition, there is a risk of adulteration with cheaper meat sources, which can be harmful to consumers. Aim: It is crucial to identify meat adulteration with distinct microbiological analysis for legal, economic, religious, and public health purposes. Methods: A total of 100 minced meat samples were collected from several markets in Sharkia Governorate, Egypt. These samples were then subjected to bacteriological testing and an advanced multiplex PCR method. This method enables the detection of bovine, equine, porcine, and dog species in meat samples with just one step. Results: The adulterated samples had a higher total bacterial count and pH values compared to pure bovine meat. These differences in bacterial count and pH values were statistically significant, with p-values of 0.843 (log10) and 0.233, respectively. The frequency of Escherichia coli occurrence was 13%, and the O111 serotype was predominant in the adulterated samples. Listeria monocytogenes and Staphylococcus aureus were isolated with prevalence rates of 3% and 29%, respectively. Besides, the SYBR-green multiplex real-time PCR assay used in this study detected adulteration with dog, equine, and porcine meats in the examined samples at rates of 9%, 5%, and 4%, respectively. Conclusion: This method provides a sensitive and specific approach to detect issues related to well-being and safety. [ABSTRACT FROM AUTHOR]

Copyright of Modern Food Science & Technology is the property of Editorial Office of Modern Food Science & Technology 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 aims to identify the pH values in preparation of coal water slurry (CWS) that were evaluated. Rheological characteristics and stability of coal water slurry (CWS) were observed with two types of impellers at pH varying from 6.99 to 7.24. The results showed that the concentration of coal water slurry, rheological characteristics and stability of CWS for propeller and rushton impellers. The parameters that are most effected on the objectives are impeller speed (N) and ratio of clearance height with diameter of tank (C/T). The third parameter, ratio of slurry height with tank diameter (Z/T), is not effecting on output. The pH values of concentrated coal water slurry are favorable to transport to coal gasifier. For propeller impeller, the pH values vary from 6.99 to 7.15; for Rushton impeller pH values vary from 7.12 to 7.24 comparatively Rushton impeller having more base which is most favorable and obtain good CWS concentration. The influence of coal particle size is also investigated on pH values for optimal parameters of equipment. [ABSTRACT FROM AUTHOR]

The results of given studies included a comparison of changes in temperature, redox potential, OH‐ions concentration and pH values in the Portland cement‐water‐additive system depending on the hydration time and features of hydration processes in the microstructure of the cement stone. The studied additives were selected taking into account the prospects for their use in the complex modifiers compositions for cement‐containing building materials. The results of electrokinetic measurements are presented and regularities and features of the influence of each studied additives on the processes of hydration structure and phase formation in Portland cement paste in the early stages of hardening are determined. The microstructure and fracture surfaces of cement stone samples formed during cement paste hardening with the optimal content of additives and features of hydration processes of cement stone were studied. The features of the mutual arrangement of individual phases in crystalline hydrate aggregates of cement stone, as well as the nature of the porosity of its microstructure, were investigated. [ABSTRACT FROM AUTHOR]

The efficient synthesis of myofibrillar protein(MRN)-gallic acid (GAD) complex in ultrasound (UID)-assisted processing is a challenging problem in food manufacturing. In this investigation, the effect of viscosity characteristics on the efficiency of UID processing in MRN-based beverages was analyzed. Both viscosity and surface tension can increase sono-physico-chemical effects on the degradation of terephthalic acid and crystal violet, with surface tension having a more significant effect (negative correlation, R2 = 0.99) than viscosity (positive correlation, R2 = 0.79). The structural indicators and microstructure demonstrated that the reaggregation and refolding of the MRN structure during the modification procedure occurred with relatively small three-dimensional dimensions. Compared to the MRN/GAD4 group, the water contact angle of the MRN/GAD7 system enhanced by 129.44%, leading to greater system stability. The ABTS-scavenging capacity of the system increased by approximately 19.45% due to the increase in viscosity of these two categories.

The current study attempts to evaluate the formation, morphology, and physico-chemical properties of zinc oxide nanoparticles (ZnO NPs) synthesized from Clinopodium vulgare extract at different pH values and to investigate their antimicrobial and biomedical application potential. The reduction of zinc ions to ZnO NPs was determined by UV spectra, which revealed absorption peaks at 390 nm at pH 5 and 348 nm at pH 9, respectively. The spherical morphology of the nanoparticles was observed using scanning electron microscopy (SEM), and the size was 47 nm for pH 5 and 45 nm for pH 9. Fourier-transformed infrared spectroscopy (FTIR) was used to reveal the presence of functional groups on the surface of nanoparticles. The antibacterial activity was examined against Staphylococcus aureus, Streptococcus pyogenes, and Klebsiella pneumonia via the agar-well diffusion method. Comparatively, the highest activities were recorded at pH 9 against all bacterial strains, and among these, biogenic ZnO NPs displayed the maximum inhibition zone (i.e., 20.88 ± 0.79 mm) against S. aureus. ZnO NPs prepared at pH 9 exhibited the highest antifungal activity of 80% at 25 mg/mL and antileishmanial activity of 82% at 400 mg/mL. Altogether, ZnO NPs synthesized at pH 9 show promising antimicrobial potential and could be used for biomedical applications. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Chinese Institute of Food Science & Technology / Zhongguo Shipin Xuebao is the property of Journal of Chinese Institute of Food Science & Technology Periodical 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.)

Cement–bentonite (CB) slurry cutoff walls are extensively utilized to restrict the horizontal flow of fluids. In this study, cement was replaced by four various contents of 0%, 10%, 20%, and 30% by natural zeolite to evaluate its effects on the unconfined compressive strength, flexural strength, tensile strength, and the coefficient of permeability of cement–bentonite–zeolite (CBZ) specimens. Since underground cutoff walls are always in danger of sulfate attack, the CBZ specimens were immersed in three different containers with three different pH values of 2, 5, and 8 to study the sulfate resistance of this material. Results have indicated that the strength of specimens decreases with an increase in zeolite content at early ages; however, increasing the amount of zeolite up to 20% improves the mechanical properties and permeability of cutoff wall materials at late ages. The bentonite/cement (B/C) ratio equal to 0.2 shows a relatively better response than B/C ratios equal to 0.14 and 0.3. Curing specimens in the sulfate environment increased the mechanical strength of specimens and decreased the coefficient of permeability at first ages. At the late ages, curing in sulfate solutions manifested disadvantageous effects on specimens; however, specimens containing zeolite indicated higher sulfate resistance than specimens without zeolite. [ABSTRACT FROM AUTHOR]

The corrosion performance of WC-12Co after different post heat treatments (1100 °C, 1100 °C + 400 °C, 1100 °C + 500 °C, 1100 °C + 600 °C), were tested in 0.05 M H 2 SO 4 , 0.1 M Na 2 SO 4 , and 0.1 M NaOH. Heat treatments influence the corrosion performance of WC-12Co in acidic and neutral environments. However, the corrosion properties for WC-12CO in alkaline solutions are independent of the heat treatments. W and C diffuse to Co from the quenching process, dramatically improving corrosion resistance, with higher annealing temperature slightly reduces the corrosion performance. The rank of corrosion nucleation parameter tested by EIS and potentio-dynamic polarisation, with the corrosion expansion rate measured by potentio-static polarisation at +0.2 V SCE , + 0.5 V SCE , and + 0.8 V SCE for 30 min are not the same. The corrosion mechanism tested in different pH values is analysed using SEM, XPS, and DFT calculations. • Heat treatments are applied on WC-12Co to increase W/C and adjust fcc/hcp ratio in Co. • The selective dissolution phase is Co in H 2 SO 4 and Na 2 SO 4 , which is opposed in NaOH. • The corrosion rate is more related to the corrosion product. • The rank of corrosion nucleation potential and corrosion propagation rate is different. • Localised corrosion forms in WC-12Co in acidic and alkaline environments. [ABSTRACT FROM AUTHOR]

Occurrence of cyanobacterial blooms in source waters challenges water treatment processes. During a successive bloom, typical characteristics of elevated cell-density and pH were observed from development to maintenance stage. However, studies about their influences on the coagulation process have been limited. Here, PACl coagulation experiments were conducted to investigate Microcystis removal with varied pH and cell-density. Results showed that PACl coagulation alone was sufficient to remove Microcystis with low cell-density (105–106 cells mL−1), since an elevated pH value (8.5–9.5) can promote PACl coagulation, possibly ascribed to sweeping cells via neutral gelatinous precipitate of alum. Nevertheless, elevated cyanobacterial biomass was a striking factor in decreasing Microcystis removal (80%–100%) by PACl coagulation, since its inhibitory effects on the coagulation process could not be offset by in situ elevated pH value. Chlorination-assisted (1 mg L−1) coagulation was recommended to treat cyanobacteria-laden source waters with high cell-density of >107 cells mL−1, as it promoted cyanobacterial removal and achieved the highest removal ratio of DOC and turbidity among these treatments. These findings will provide an important reference for water supplies to choose the proper water treatment process to treat cyanobacteria-laden source waters during a successive bloom. HIGHLIGHTS Elevated pH (8.5–9.5) enhanced cyanobacterial removal by PACl coagulation.; Elevated cell-density (107 cells mL−1) hindered cyanobacterial removal by PACl coagulation.; Coagulation alone was sufficient to remove cyanobacteria of 105–106 cells mL−1.; Pre-chlorination was necessary to treat elevated cyanobacterial biomass of 107 cells mL−1.;

Summary: The spontaneous combustion characteristics of residual air‐dried coal change after soaking, which can pose a threat to coal mining safety. To study the effects of increasing alkalinity, pH values (7–11), on the spontaneous combustion characteristics of coal, we conducted a number of experiments using thermogravimetry (TG) and Fourier‐transform infrared spectroscopy (FTIR). TG was used to investigate parameters including the ignition index Di, combustion characteristic index (S), combustion intensity index (Hf), and activation energy (E) to show any variations in oxidative exothermic characteristics of coal. The results showed that the values of Di and S of the coal samples after alkaline treatment, increased with the increasing pH values. However, the values of Hf and E followed the opposite trend. To further explain the reason behind these variations, we investigated functional groups of coal using FTIR. These results indicated that the active functional groups, including oxygen‐containing functional groups, methyl and methylene groups, of the coal, increased after alkaline treatment, which showed microscopically that the coal was more active after soaking. These parameter variations together illustrate that the oxidation activity of the coal was enhanced after the alkaline treatment, and that it is more prone to spontaneous combustion. [ABSTRACT FROM AUTHOR]

The synthesized condition by means of controlling pH values of the reaction mixtures has been explored. Three Mn2+, Cd2+ ion coordination polymers with the fully deprotonated cis, cis, cis-1,2,3,4-cyclopentanetetracarboxylic acid (H4L) ligand were synthesized and characterized, sometimes incorporating different auxiliary ligand: {[Mn(H2O)6][Mn3(L)2(H2O)2]}·3H2O (1), [Cd2L(H2O)4] (2) and [Cd2Lphen)2(H2O)2]·3H2O (3) (phen = 1,10-phenanthroline). With an initial of pH values of 6.0, 4.0 and 9.0 of the reaction mixtures, we get the compounds 1, 2 and 3, respectively. In crystal of 1, two crystallographic different Mn2+ ions (Mn1 and Mn2) form a negatively charged coordination polymeric chain, which contains a centrosymmetrically linear trinuclear Mn2+ cluster (Mn3L2) subunit; another crystallographically independent Mn2+ ions (Mn3) coordinated by six water molecules act as counter ions to link the neighboring coordination polymeric chains via intermolecular H-bond interactions. The Mn2+ ions in 1 were completely replaced by Cd2+ ions to give 2 and 3, respectively. Complex 2 shows 3D distributions of Cd2+ ions while Complex 3 displays 2D networks contributed by intermolecular H-bond interactions. Three complexes exhibit distinct thermal decomposition mechanisms, and the deprotonated cis, cis, cis-1,2,3,4-cyclopentan-etetracarboxylic acid ligands decompose in 420–700 °C to give the residue MnO + C in 1 and CdO in 2 and in 3. Complex 1 shows a complicated magnetic behavior of coexistence of antiferromagnetic exchange interactions between neighboring Mn2+ ions. [ABSTRACT FROM AUTHOR]

The current study attempts to evaluate the formation, morphology, and physico-chemical properties of zinc oxide nanoparticles (ZnO NPs) synthesized from Clinopodium vulgare extract at different pH values and to investigate their antimicrobial and biomedical application potential. The reduction of zinc ions to ZnO NPs was determined by UV spectra, which revealed absorption peaks at 390 nm at pH 5 and 348 nm at pH 9, respectively. The spherical morphology of the nanoparticles was observed using scanning electron microscopy (SEM), and the size was 47 nm for pH 5 and 45 nm for pH 9. Fourier-transformed infrared spectroscopy (FTIR) was used to reveal the presence of functional groups on the surface of nanoparticles. The antibacterial activity was examined against Staphylococcus aureus, Streptococcus pyogenes, and Klebsiella pneumonia via the agar-well diffusion method. Comparatively, the highest activities were recorded at pH 9 against all bacterial strains, and among these, biogenic ZnO NPs displayed the maximum inhibition zone (i.e., 20.88 ± 0.79 mm) against S. aureus. ZnO NPs prepared at pH 9 exhibited the highest antifungal activity of 80% at 25 mg/mL and antileishmanial activity of 82% at 400 mg/mL. Altogether, ZnO NPs synthesized at pH 9 show promising antimicrobial potential and could be used for biomedical applications.

Adsorption behavior is rarely investigated as a heavy metal solidification mechanism in alkali-activated municipal solid waste incineration (MSWI) fly ash compacts. This study simulates the adsorption behavior and solidification mechanism of Pb(II) on synthetic C-S-H gel with low and high Ca/Si ratios in high alkaline internal pore solution environments of alkali-activated MSWI fly ash compacts. The study examines the fraction of Pb(OH) 3 - in a Pb(II) solution (100 mg/L) at pH 11.8 and 12.4, with percentages of 85.9–90.6 % and 93.4–95.1 %, respectively. pH values are identified as the key parameter affecting the adsorption capacity of C-S-H for Pb(II). The equilibrium adsorption capacities (Q e) values of Pb(OH) 3 - (pH = 11.8) for C-S-H with Ca/Si ratios 1.20 and 0.60 are approximately 104 mg/g and 110 mg/g. At pH 12.4, the C-S-H gel with a Ca/Si ratio = 1.20 performs better in terms of adsorption. The adsorption of Pb(OH) 3 - by C-S-H is predominantly a chemisorption process at pH 11.8. Based on the Δ G 0 data, the adsorption process is determined to be spontaneous. The 1.16 eV LUMO and HOMO difference for Si 2 O(OH) 6 + Pb(OH) 3 -, compared with the 3.92 eV difference for Si 3 O 2 (OH) 8 + Pb(OH) 3 -, indicates a lower difficulty of electron transition in the reaction between Si 2 O(OH) 6 and Pb(OH) 3 -. XPS and FTIR results confirm the dehydration and combination of Pb(OH) 3 - and Si-OH in a silicate tetrahedron (Q1 or Q2) on the C-S-H surface to create Si-O-Pb. Partial Ca(II) in C-S-H gel can be replaced or released during the Pb(II) adsorption process. These findings hold significant theoretical importance for the adsorption and solidification mechanism of Pb(II) in alkali-activated MSWI fly ash specimens. • At pH >11.5, the majority of Pb(II) exists in the solution as Pb(OH) 3 -. • Pb(OH) 3 - adsorption by C-S-H is spontaneous and predominantly a chemisorption process. • pH value is the key parameter affecting the adsorption capacity of C-S-H for Pb(II). • Pb(Ⅱ) can partially replace Ca(Ⅱ) in CS1.20 during the adsorption process. • Pb(OH) 3 - is more likely to undergo polycondensation with non-bridging oxygen in the double silicon chain, forming Si-O-Pb bonds. [ABSTRACT FROM AUTHOR]

[Display omitted] • Preheating treatment at alkaline pH can reduce the average particle size and turbidity of thermal aggregates. • The smaller particle size helps to form a tight gel network structure. • With increasing the preheating temperature and pH, the WHC and gel strength of gels improved. The goals of this study were to investigate the effect of preheating conditions on the formation of thermal aggregates of commercial soy isolate protein (SPI) and to characterize the textural properties and microstructure of acid-induced SPI gels. SPI was subjected to preheating treatments at different temperatures (85 °C, 95 °C) and pH values (7.0, 7.5, 8.5, 9.5), and the treated SPI was then used to form acid-induced gels. Characterization of the different gels showed that lower temperatures and pH values favored protein aggregation and the formation of larger aggregates, while higher temperatures and pH values led to a lower degree of aggregation and the formation of smaller aggregates. The lowest average particle size (340.77 nm) and turbidity (0.063), and the highest solubility (81.79 %) were obtained when the preheating temperature of the thermal aggregates was 95 °C and the pH was 9.5. Higher preheating temperature and pH values caused the unfolding of SPI's tertiary structure, decreased the content of β-sheet structure, and increased the exposure of hydrophobic groups and free sulfhydryl groups. These exposed groups facilitated protein–protein interactions during network assembly, resulting in denser and stronger gel networks. Notably, SPI subjected to higher temperatures and pH values exhibited greater binding capacity for water molecules, higher water holding capacity, and gel strength. Overall, the results showed that modification of preheating temperature and pH can control the formation state of SPI thermal aggregates, ultimately impacting the properties of SPI acid-induced gels. [ABSTRACT FROM AUTHOR]

• Pb(OH) 3 - adsorption by C-A-S-H is mainly chemisorption with spontaneity. • Pb(Ⅱ) Adsorption behavior by varied Ca/Si and Al/Si ratios of C-A-S-H are studied. • Active Si-OH (Q1 or Q2b) dehydrate and condense with Pb(OH) 3 - to form Si-O-Pb bonds. • Pb(Ⅱ) can partially replace Ca(Ⅱ) in C-A-S-H during the adsorption process. • Pb(OH) 3 - preferentially forms Si-O-Pb in the 2SA-S-Pb transformation pathway. Calcium silicate aluminate hydrate (C-A-S-H) is the main hydration product and its porous adsorption property can effectively inhibit Pb(II) leaching from alkaline pore solution of alkali-activated municipal solid waste incineration (MSWI) fly ash compacts. The study examines how different ratios of Ca/Si and Al/Si in C-(A)-S-H affect Pb(II) adsorption behavior and mechanism in high alkaline conditions. The results showed that Al-doped C-A-S-H gels have increased specific surface area and cumulative pore volume, and slightly decreased average pore size. Pb(OH) 3 - adsorption by C-A-S-H was mainly chemisorption with spontaneity. Temperature, pH value, Al/Si and Ca/Si ratios of C-A-S-H affected Pb(II) adsorption. Equilibrium adsorption capacity (Q e) initially increased then decreased with higher Al/Si for C-A-S-H with Ca/Si 0.60 but decreased with higher Al/Si for Ca/Si 1.20. Active Si-OH (Q1 or Q2b) and Al-OH (Q2(1Al)) in aluminosilicate tetrahedra chains dehydrate and condense with Pb(OH) 3 - to form Si-O-Pb or Al-O-Pb bonds. Higher interlayer water content in low Ca/Si and Al/Si C-A-S-H facilitated ion exchange during Pb(II) adsorption. After adsorption, aluminosilicate tetrahedra chain length increased while interlayer water content decreased. Ca(II) and Pb(II) in C-A-S-H underwent partial ion exchange during the adsorption process. Simulation results indicate Pb(OH) 3 - was more likely to polycondensate with silica tetrahedral bridging oxygen in Si 2 AlO 2 (OH) 8 to form Si-O-Pb than Al-O-Pb bonds. These findings provide theoretical support for designing dosages of alkali activators and doped aluminosilicate minerals to improve the solidification efficiency of Pb(II) in alkali-activated MSWI fly ash compacts. [ABSTRACT FROM AUTHOR]

The mycelium-free supernatant (MFS) of a five-day-old culture medium of Fusarium oxysporum was used to synthesize gold nanoparticles (AuNPs). The experimental design of the study was to answer the question: can this production process of AuNPs be controllable like classical chemical or physical approaches? The process of producing AuNPs from 1 mM tetrachloroauric (III) acid trihydrate in MFS was monitored visually by color change at different pH values and quantified spectroscopically. The produced AuNPs were analyzed by transmission electron microscopy, scanning electron microscopy, and energy-dispersive X-ray spectroscopy. The presence of capping agents was confirmed by Fourier transform infrared spectroscopy (FTIR). Two AuNP samples with acidic and alkaline pH were selected and adjusted with the pH gradient and analyzed. Finally, the size and zeta potential of all samples were determined. The results confirmed the presence of the proteins as capping agents on the surface of the AuNPs and confirmed the production of AuNPs at all pH values. All AuNP samples exhibited negative zeta potential, and this potential was higher at natural to alkaline pH values. The size distribution analysis showed that the size of AuNPs produced at alkaline pH was smaller than that at acidic pH. Since all samples had negative charge, we suspect that there were other molecules besides proteins that acted as capping agents on the surface of the AuNPs. We conclude that although the biological method of nanoparticle production is safe, green, and inexpensive, the ability to manipulate the nanoparticles to obtain both positive and negative charges is limited, curtailing their application in the medical field. [ABSTRACT FROM AUTHOR]

Our aim was to assess the blood physiology and antioxidant and immune responses of the olive flounder (Paralichthys olivaceus) following pH changes in the water. P. olivaceus (mean weight 95.7 ± 6.5 g and mean length 21.4 ± 1.3 cm) were exposed to the different pH levels (pH 5, 6, 7, 8, 9, and 10) for 2 weeks. Blood physiology parameters, such as the levels of hematocrit, magnesium, glucose, glutamic oxalate transaminase (GOT), glutamic pyruvate transaminase (GPT), and alkaline phosphatase (ALP) were significantly altered by low (acidic) pH or high (alkaline) pHs. With regard to antioxidant responses, the superoxide dismutase (SOD) and glutathione S-transferase (GST) activities in the liver were significantly altered by the pH changes, but there were no significant changes of these activities in the gill tissues. The immunoglobulin M levels increased significantly at pH 10 after 2 weeks. The results of this study suggest that pH changes (acidity: < pH 6, alkalinity:> pH 9) affect blood physiology, as well as antioxidant and immune responses in P. olivaceus.

Disintegration of rock caused by wetting-drying cycles seriously threatens the long-term stability of rock mass. To investigate the slaking behavior of rocks, wetting-drying cycle slaking tests were carried out on two types of tuffs with aqueous solutions considering the initial pH values of 2, 7, and 12. The disintegration processes of the rock samples were observed, and the variation trends of the particle distributions of slaked materials were analyzed. The results show significant differences in the slaking durability between the two types of tuffs with different mineralogical compositions. The pH values of the aqueous solutions have influences on slaking characteristics for the same tuff sample. Clay minerals such as montmorillonite are the main factors for rock disintegration. In addition, the microstructure of rocks is also a factor affecting slaking durability. Water-rock chemical reaction occurs during the wetting procedure of each wetting-drying cycle. The tuff samples, which are more strongly influenced by the water-rock reaction in solution with a low pH value, are more prone to disintegrate. [ABSTRACT FROM AUTHOR]

Metal-contaminated plants after phytoremediation provide organic matter and trace metals for anaerobic fermentation. In this study, alfalfa straw harvested from an abandoned iron mine was used for anaerobic fermentation. The variation of metal speciation during the anaerobic fermentation process and the influences on fermentation parameters were investigated. The results showed that the group adding alfalfa increased the peak daily biogas yield by 33.40 % compared to the group with cow dung only. Fe in the fermenter was predominated by the soluble and the residual fraction. Cu was transformed from soluble Cu to residual Cu with the fermentation progressed. On the 13th day of fermentation, the percentage of soluble Fe decreased while the percentage of soluble Cu, Ni and Zn increased which induced the daily biogas yields peak. Metal speciation was correlated to the fermentation parameters. Daily biogas yields were negatively correlated to the acid-extractable fraction of Ni and Zn (p < 0.05). pH was negatively correlated to the soluble Cu, the acid-extractable fraction of Cu and Zn (p < 0.05), while positively correlated to the reducible and oxidizable Fe (p < 0.01). Further adding metals promoted the biogas production of alfalfa by bringing forward the daily biogas peak and increasing the peak yields. In particular, adding Cu only produced more biogas than adding other metals (single or multiple). Exogenous metals addition generally resulted in more acid-extractable fraction of Cu, Ni and Zn, i.e. the mobility of these metals increased. 19 % of Fe was activated into acid-extractable fraction after the addition of Ni. The results of this study are expected to provide references for the reutilization of contaminated biomass and optimizing the metal contained fermentation process. [ABSTRACT FROM AUTHOR]

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Tomato pith necrosis caused by Pseudomonas corrugata and other Pseudomonas species is a common disease occurring worldwide, including Saudi Arabia. We demonstrated how the pith necrosis length induced by P. corrugata strain KSU-RT3 significantly increased (>31%) when it was co-inoculated along with P. fluorescens strain KSU-AT1. The latter exhibited antagonistic activity against P. corrugata in vitro and revealed its ability to induce pith necrosis symptoms on tomato when inoculated individually. The two bacterial strains could grow in the presence of NaCl concentrations of up to 80 mM. The growth of the two bacterial strains was suppressed under acidic conditions (pH 4–5). In vivo, the pith necrosis length was significantly increased by 16.15% under irrigation with saline water. A short exposure of 14 days to high salinity (in the absence of pathogens) was sufficient to render the tomato plants significantly more susceptible to subsequent inoculation with either of the two pathogens or when inoculated in combination. In conclusion, our study showed that acid soil and saline soil watered with fresh water showed decreased infection, only neutral to alkaline soil (up to pH 8) and saline soil watered with saline water showed increased infection. So an important cultural measure could be to keep soil pH reasonably low. More antagonistic P. fluorescens strains should be tested for pathogenicity before large-scale application to avoid the risk of introducing strains, such as our P. fluorescens strain KSU-AT1 that proved to be pathogenic to tomato plants. [ABSTRACT FROM AUTHOR]

Mouthwash is a solution used for cleaning the oral cavity, usually stored at a certain time without considering the changes of pH value and antibacterial activities. As a consequence, some herbal components intended in mouthwash application are used. One of the herbals potentials to be used in mouthwash is cashew (Anacardium occidentale Linn.) stem bark, which contains some phenolic compounds having an anti-bacterial agent. The purpose of this study was to determine the storage effect of cashew stem bark extract as mouthwash on pH value and inhibitory growth of Staphylococcus aureus. The study used mouthwash formula containing cashew stem bark extract with different concentrations using sorbitol 1% and peppermint oil 1.5% as vehicles in each 10 mL of formula. The measurements of pH value and the growth inhibition of S. aureus were carried out using pH meter and diffusion method on days 1, 7 and 14, respectively. The data obtained were analyzed using one-way Analysis of Variance (ANOVA). The results showed that there was significant difference (P < 0.05) on the effect of storage time in mouthwash containing cashew stem bark extract on pH value and the inhibitory growth of S. aureus. Conclusion: the storage time of cashew stem bark extract can affect pH value and inhibitory growth of Staphylococcus aureus as mouthwash. [ABSTRACT FROM AUTHOR]

Three pH values(5.0, 7.0, 9.0) were set to investigate the growth and algal toxin production of Microcystis aeruginosa under stress of low concentration pyrene (0.001 5 mg/L). The results showed that the growth of Microcystis aeruginosa under low concentration pyrene stress was significantly promoted under the condition of pH value, while the effect of toxin production was different under different pH value, with the expression as the cell density of the treatment group under low con- centration pyrene stress higher than that of the blank control group, and when pH is 9.0, the specific growth rate of Microcystis aeruginosa is the highest, and its generation time is also the shortest. The content of Chlorophyll a in the treatment group with low concentration of pyrene stress was lower than that in the blank control group, and at pH 9.0 and pH 7.0, the increase of Chlorophyll a was significantly greater than that at pH 5.0. Pyrene at low concentration at pH 7.0 inhibited the yield of intracellular and extracellular Microcystin-LR. Under the condition of pH 9.0, pyrene of low concentration promoted the yield of Microcystin-LR in and out of cells. The results showed that the growth of Microcystis aeruginosa and the yield of Microcystin-LR would be affected by pH value when there was low concentration of PAHs in water. Therefore, the pH value should not be ignored when assessing the risk of chemicals that promote Microcystin-LR production in eutrophic water. [ABSTRACT FROM AUTHOR]

Nano-phosphors YPO4:2%Sm3+ with different pH values were synthesized with hydrothermal method. The influence of pH on structure, morphology and fluorescence property of nano-phosphor was researched. The product composition, structure, morphology and luminescent properties were characterized and analyzed with X-ray diffractometry (XRD), scanning electron microscopy (SEM and EDS), infrared spectrometer (FT-IR), ultravoilet spectrometer (UV), fluorescence spectrophotometer (FL) and other instruments. The research results indicated that: the tetragonal crystal system structure of pure phase can be obtained at pH 1–5, and the mix phases of tetragonal and hexagon can be obtained at pH 7–9. The product morphology is fusiform at pH 1; spherical at pH 3–5; and bar-shaped at pH 7–9. As pH is gradually increased from 1 to 9, the fluorescence intensity of nano-phosphor is gradually decreased and then increased. The nano-phosphor with pH 1 has the maximum fluorescence intensity and fluorescence lifetime; moreover, it has better fluorescence thermal stability, and its activation energy is 0.233 eV. [ABSTRACT FROM AUTHOR]

The mycelium-free supernatant (MFS) of a five-day-old culture medium of Fusarium oxysporum was used to synthesize gold nanoparticles (AuNPs). The experimental design of the study was to answer the question: can this production process of AuNPs be controllable like classical chemical or physical approaches? The process of producing AuNPs from 1 mM tetrachloroauric (III) acid trihydrate in MFS was monitored visually by color change at different pH values and quantified spectroscopically. The produced AuNPs were analyzed by transmission electron microscopy, scanning electron microscopy, and energy-dispersive X-ray spectroscopy. The presence of capping agents was confirmed by Fourier transform infrared spectroscopy (FTIR). Two AuNP samples with acidic and alkaline pH were selected and adjusted with the pH gradient and analyzed. Finally, the size and zeta potential of all samples were determined. The results confirmed the presence of the proteins as capping agents on the surface of the AuNPs and confirmed the production of AuNPs at all pH values. All AuNP samples exhibited negative zeta potential, and this potential was higher at natural to alkaline pH values. The size distribution analysis showed that the size of AuNPs produced at alkaline pH was smaller than that at acidic pH. Since all samples had negative charge, we suspect that there were other molecules besides proteins that acted as capping agents on the surface of the AuNPs. We conclude that although the biological method of nanoparticle production is safe, green, and inexpensive, the ability to manipulate the nanoparticles to obtain both positive and negative charges is limited, curtailing their application in the medical field.

In this study, experiments were designed to reveal in-depth information of the effect of pH and hydraulic retention time (HRT) on biohydrogen fermentation from liquid swine manure supplemented with glucose using an Anaerobic Sequencing Batch Reactor (ASBR) System. Five values of HRT (8, 12, 16, 20, and 24 h) were first tested and the best HRT determined was further studied at five pH levels (4.4, 4.7, 5.0, 5.3, and 5.6). The results showed that for HRT 24 h, there was a dividing H2 content (around 37%) related to the total biogas production rate for the ASBR System running at pH 5.0. When the H2 content went beyond 37%, an appreciable decline in biogas production rate was observed, implying that there might exist an H2 content limit in the biogas. For other HRTs (8 through 20 h), an average H2 content of 42% could be achieved. In the second experiment (HRT 12 h), the highest H2 content (35%) in the biogas was found to be associated with pH 5.0. The upswing of pH from 5.0 to 5.6 had a significantly more impact on biogas H2 content than the downswing of pH from 5.0 to 4.3. The results also indicated good linear relationships of biogas and H2 production rates with HRT (r=0.9971 and 0.9967, respectively). Since the optimal ASBR operating conditions were different for the biogas/H2 production rates and the H2 yield, a compromised combination of the running parameters was determined to be HRT 12 h and pH 5.0 in order to achieve good biogas/H2 productions.

Various Maillard reaction systems were established to investigate the effect of maize bran feruloylated oligosaccharides (FOs) on the formation of both endogenous and exogenous advanced glycation end-products (AGEs) under different pH values. The formation of AGEs and four kinds of dicarbonyl compounds (glyoxal, methylglyoxal, 3-deoxyglucosulose, 2,3-butanedione) were determined by fluorescence spectrophotometry and HPLC, respectively. Results showed that maize bran FOs effectively inhibited the production of fluorescent AGEs. Moreover, increase in pH, temperature and concentration of FOs in reaction systems elevated the inhibition effects of feruloylated oligosaccharides, fluorescent AGEs and dicarbonyl compounds. Mainly because of the ester bond of FOs at high pH and/or temperature systems are readily to be hydrolyzed, resulting in the release of ferulic acid. Unlabelled Image • FOs inhibit the production of both endogenous and exogenous AGEs. • Increase in pH, temperature and concentration elevate the inhibition effects. • FOs can inhibit the oxidation of adducts. • FOs can inhibit the adduction between protein and dicarbonyl compounds. • FOs can inhibit the formation of dicarbonyl compounds. [ABSTRACT FROM AUTHOR]

The measurement of pH value of solutions is crucial in many fields of modern science. We deposited MWCNTs coating on a planar capacitive structure consisting of interdigitated gold and aluminium electrodes on a flexible Kapton foil substrate, to develop the pH sensors. MWCNTs coating acts as an H+ ion sensing layer. The complete structural, mechanical and electrical characterization has been performed. The sensors involve supplying gold/aluminium electrodes with an input voltage and measuring the changes in the capacitance, resistance and impedance when the sensor chip is exposed to different pH solutions. The experimental setup was built for dipping the sensors in the sample liquids of different pH values from 4 to 9, being very flexible, reproducible and robust. • pH sensors fabricated using two conductive materials gold (Au) and aluminium (Al). • MWCNT coating was created on the top of IDC sensor structure to increase sensitivity. • Complete structural, mechanical and electrical characterization has been performed. [ABSTRACT FROM AUTHOR]

Abstract In the present work, we have synthesized the SnO 2 nanostructures via precipitation method under optimal conditions at different pH values (3, 7 and 11) and studied the effect of different pH values on the structural, optical and electrical properties. The prepared samples are characterized by XRD, FESEM, TEM, PL, UV–vis, FTIR spectroscopy and EIS measurements. XRD analysis reveals the tetragonal crystal structure for the prepared SnO 2 nanostructures. TEM images show that the morphology of SnO 2 nanostructures changed from spherical to hexagonal as pH values increased from 3 to 11. The deconvoluted PL spectra show various defects present in the synthesized samples that act as luminescent centers. The absorption spectra revealed that the maximum optical band-gap is obtained for SnO 2 nanostructures synthesized using acidic solutions. The FTIR spectrum verifies the presence of stretching vibration mode of O-Sn-O bond and, stretching and bending bonds of O H bonds in the prepared samples. A detailed exploration on frequency and temperature dependent impedance properties of SnO 2 nanostructures has been done with the change in pH values. [ABSTRACT FROM AUTHOR]

This study explored the formation of composite gels via pH-modulated whey protein isolate (WPI) and deacetylated konjac glucomannan (KGM) solutions. The physicochemical properties, gelation characteristics, and microstructure of WPI-KGM gels were evaluated at varied pH levels (2−10). Findings revealed that WPI and deacetylated KGM failed to generate a stable gel at pH extremes (2 or 10). However, under optimal pH conditions (4 or 8), the WPI-KGM system yielded gels exhibiting superior water-holding capacity and hardness after heat treatment, with the composite gel at pH 4 demonstrating enhanced whiteness compared to that at pH 8. Textural and rheological assessments suggested that moderate pH levels favor the formation of well-structured gels. Scanning electron microscopy showed denser structures at pH 4 and 8, contrasting with disordered, coarse gel networks at pH 2 and 6. At pH 4, the WPI-KGM gel structure was primarily maintained by electrostatic and hydrophobic interactions, whereas at pH 8, disulfide bonds became pivotal. Overall, our findings underlined the importance of appropriate pH conditions in facilitating composite gel formation, offering practical insights for heat-induced gel material development in the food industry. [Display omitted] • Optimal pH (4 or 8) promotes well-structured gel formation in WPI-KGM system. • WPI-KGM gels at pH 4 show superior whiteness and water-holding capacity. • Electrostatic and hydrophobic interactions uphold WPI-KGM gel structure at pH 4. • At pH 8, disulfide bonds become critical for maintaining WPI-KGM gel structure. [ABSTRACT FROM AUTHOR]

The catalytic activity of photocatalyst is strongly dependent on the phase structures, grain size and particle morphology of the catalyst. In this paper, the controlled synthesis of bismuth(Bi) with different morphologies (nanoparticles, nanorods, nanocubes and micro-spheres) has been successfully realized by adjusting different experimental parameters. The Bi nanostructures were analyzed by X-ray diffraction (XRD), scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), Fourier-transform infrared spectroscopy (FT-IR), Brunauer-Emmett-Teller (BET), photoluminescence (PL), UV–vis absorption spectroscopy (UV–Vis). The PL spectra shown that the reduction of the size of Bi nanomaterials can decrease the recombination rate of photoelectrons and holes, which leads to the effective separation of photocharge carriers and the better photocatalytic performance of Bi nanomaterials. The energy gaps of Bi nanoparticles, nanorods, nanocubes and microspheres are 2.57 eV, 2.69 eV, 2.99 eV and 3.16 eV respectively. The degradation activity of Bi nanostructures with different sizes on organic dyes showed that 99.9%, 98.9%, 97% and 68.3% degradation of RhB was observed after 90-min visible light irradiation for Bi nanoparticles (20–50 nm), nanorods (20 nm in diameter and 1 μm in length) nanocubes (150–200 nm) and micro-spheres (10 μm), respectively. The results indicated that if the grain sizes of the Bi samples are reduced from micro-size to nano-size, their catalytic activities dramatically increase. At the same time, the achieved results also reveal that Bi 2 O 3 and BiOCl were found in Bi surfaces before and after catalytic degradation, which was confirmed by XPS and FTIR technology. In addition, the catalytic activity of Bi with the same morphology increased with the decrease of pH value. Furthermore, the Bi samples still retained excellent catalytic activity after 40 cycles, the removal rate could also reach 73.5% for the 40th cycling. • Bismuth with different morphologies was successfully synthesized. • Bismuth performed different catalytic activities at different pH values. • The catalytic activity increases as the decrease of bismuth size. • Bismuth retained excellent catalytic activity after 40 cycles. [ABSTRACT FROM AUTHOR]

The article deals with two wells in the country of Brno-district (Brčálka well and Well Olšová). The aim of work was monitoring of elementary parameters of water at regular monthly intervals to measure: water temperature, pH values, solubility oxygen and spring yield. According to the client's requirements (Lesy města Brno) laboratory analyzes of selected parameters were done twice a year and their results were compared with Ministry of Health Decree no. 252/2004 Coll.. These parameters: nitrate, chemical oxygen demand (COD), calcium and magnesium and its values are presented in graphs, for ammonium ions and nitrite in the table. Graphical interpretation of spring yields dependence on the monthly total rainfall and dependence of water temperature on ambient temperature was utilized. The most important features of wells include a water source, a landmark in the landscape, aesthetic element or resting and relaxing place. Maintaining wells is important in terms of future generations.

According to the principles of simultaneous equilibria and mass equilibria, CuInSe2 (CIS) were prepared by total aqueous process at normal pressure and room temperature. A series of thermodynamic equilibrium equations were deduced for the complex system of Cu+-In3+-Se2--NH3-L2--Cl--H2O (T=298 K), and the equilibrium curves of lgc-pH were drawn. It was found from these equilibrium diagrams that[NH3]T primarily affected the[Cu+]T concentration,[L2-]T influenced the[In3+]T concentration, and[Cl-]T had impact on both. The highest precipitation coefficient was obtained at pH 7.0-8.5. As a result, based on the principles of simultaneous equilibria and mass equilibria of the Cu+-In3+-Se2--NH3-L2--Cl--H2O system (T=298 K) and used total aqueous process at normal pressure and room temperature, CIS nanoparticles can be synthesized by adjusting the pH value to 7.0-8.5, and their size is about 20 to 50 nm.

The effect of pH values on the corrosion behavior of Q235 steel in simulated acidic soils was investigated by weight-loss measurement, scanning electron microscopy (SEM), X-ray diffraction (XRD) analysis and polarization curve analysis. When the pH values are 4.0, 4.5 and 5.1, the corrosion rate of Q235 steel are 0.68, 0.48 and 0.42 mm·a-1, respectively. With the increase of soil pH values, the rust becomes more compact and the etch pits change from narrow and deep to wide and shallow. All the corrosion products are mainly composed of SiO2, α-FeOOH, γ-FeOOH, Fe2O3 and Fe3O4, and the mass ratio of α-FeOOH/γ-FeOOH in the corrosion products is higher with increasing pH values. Additionally, polarization curve analysis shows that when the soil pH value rises, the corrosion potential of Q235 steel increases, the corrosion current density decreases, and the corrosion rate becomes lower.