pH Values Research Articles

Generation and geochemical characteristics of acid rock drainage (ARD) in Barton Peninsula, King George Island (KGI), maritime, Antarctica

This study deals with the generation, geochemical characteristics, and environmental impacts of acid rock drainage (ARD), a global environmental problem, on the Barton Peninsula. To elucidate the governing processes and to assess the environmental hazards of ARD, we present chemical data from lakes, ponds, and creeks with a wide range of pH values. We also provide mineralogical and geochemical compositions of sediments and bedrocks. Compared to weak-acidic and neutral waters, waters that display typical characteristics of ARD with low pH (3.7 to 4.2), high sulfate (46 to 92 mg/L), and Fe (0.8 to 16.5 mg/L) occur in the northern tip of the peninsula. Acidic waters with the highest cation (e.g., K, Na, Si, and Ca) and anion (e.g., SO4) compositions indicate ARD-enhanced rock weathering in the peninsula. Consistently, quantifying of chemical weathering degree yields the highest chemical index of alteration (CIA) and the mafic index of alteration (MIA) with the lowest ICV values for sediments from the acidic waters. Enrichment factors (EFs) calculated for As, Co, Cd, Cu, Pb, Zn, and Ni indicate severe to minor enrichment for As and Pb metals, respectively in the acidic water-associated sediments. Heavy metal concentrations of acidic waters also display the highest values for the peninsula, with Fe, Cu, and Cd metals exceeding the chronic aquatic toxicity limit (CAT). Therefore, geochemical records of acidic waters and sediments, especially lakes, may help in tracing the long-term environmental impacts of ARD, while sediments obtained from the weak acidic and near-neutral waters, together with water chemistry data, may provide a better representative composition of the bedrocks with neutralizing potential. The data presented here may contribute to predicting the source/s, and extent of future ARD generation in the peninsula, which is likely to be enhanced by increased chemical weathering due to climate warming.

Water-in-water emulsions stabilized by nano-chitin

A water-in-water (W/W) emulsion consists of microdroplets was formed by the spontaneous liquid–liquid separation by mixing polyacrylic acid and chitosan oligosaccharide in water, and these microdropletes were stabilized by nano-chitin, formed water-in-water Pickering emulsions. By taking the advantage of interfacial adsorption of nano-chitin, the W/W emulsion droplets composed of polyacrylic acid/chitosan oligosaccharide (COS/PAA) polyelectrolyte coacervate were successfully stabilized. Research results indicated that composite microspheres were formed by the nano-chitin stabilized COS/PAA emulsion, and the size of these composite microspheres was related to the concentration and morphology of the nano-chitin. As the concentration of nano-chitin increases, the size of the composite microspheres first increases and then decreases, gradually becoming more uniform; whereas a decrease in the length of nano-chitin will lead to an increase in the size of the composite microspheres. The formation of composite microspheres may be due to the electrostatic interactions between nano-chitin and the emulsion droplets. In addition, the composite microspheres exhibit the best release effect for berberine hydrochloride at a pH value of 3.

Development of Ready to Drink Banana Pseudostem Beverage Incorporated with Pineapple and Grape Extract

Background: Banana pseudostem (Musa acuminata) comprises nearly 30% of plant biomass and carries a substantial quantity of fiber and moisture. Banana pseudostem beverage was developed from banana tender core, natural extracts (Pine apple and Grape) and 2% citric acid used as an antibrowning agent. The present study aimed to develop ready-to-drink banana pseudostem juice incorporated with pineapple and grape extract. The banana pseudostem juice (80%) was incorporated with pineapple (20%) and grape (20%) extracts. Methods: The proximate composition of the ready-to-drink banana pseudostem beverage and the physicochemical properties of banana pseudostem extract were analyzed using standard procedures. Sensory evaluation and microbial quality were analyzed for ready-to-drink banana pseudostem beverages stored at 25°C and 4°C. The beverages were evaluated at 6 days interval period. Result: The ready-to-drink beverages were evaluated at a 6-day interval period. The result of the physicochemical properties of the ready-to-drink banana pseudostem beverage incorporated with pineapple and grape extract during storage at ambient and refrigerated temperature. The banana pseudostem beverage pH value gradually increased and its acidity value decreased. The total soluble solids remained constant, viscosity at 25°C was decreased, at 4°C viscosity was increased during the storage period up to 12 days. During storage conditions, the total soluble solids remain constant, while the viscosity increased at 4! and reduced at 25°C. Minimal substantial changes were observed in the quality of ready-to-drink banana pseudostem beverages during storage conditions. The pineapple extract-flavored pseudostem beverages during storage conditions. The pineapple extract-flavored pseudostem beverage was very well-liked by consumers, according to the organoleptic evaluation. The quality of ready-to-drink banana pseudostem beverages was minimal significant changes were observed. Based on the organoleptic evaluation, the pineapple extract flavored pseudostem beverage was highly accepted by consumer preference. The banana pseudostem beverage incorporated with pineapple extracts was microbiologically safe for 12 days at 25°C and 4°C for human consumption. After 12 days at (25°C) and (4°C), the banana pseudostem beverage incorporated with pineapple extracts proved microbiologically safe.

Ethanol and 2-phenylethanol production by bee-isolated Meyerozyma caribbica strains

Investigating the biotechnological potential of wild microorganisms is paramount for optimizing bioprocesses. Given this premise, we looked for yeasts in Brazilian native stingless bees, considering the recognized potential of pollinating insect-associated microorganisms for the production of volatile organic compounds (VOCs). Two yeast strains of the species Meyerozyma caribbica were isolated from bees Scaptotrigona postica and evaluated for their fermentative capacity. Both yeasts were capable of fermenting sucrose (the main sugar used in the Brazilian ethanol industry) with over 90% efficiency and yields of up to 0.504 g/g. Through an experimental design analysis (CCD), it was verified that the ethanol productivity of these yeasts can also benefit from high concentrations of sucrose and low pH values, desirable traits for microorganisms in this biofuel production. At the same time, CCD analyses also showed the great capacity of these M. caribbica strains to produce another alcohol of broad biotechnological interest, 2-phenylethanol. Interestingly, the statistical analyses demonstrated that greater production of this compound can occur at high sugar concentrations and low availability of nitrogen sources, which can be easily achieved using residual low-cost feedstocks. Thus, our results suggest that these M. caribbica strains may be efficiently used in both ethanol and 2-phenylethanol production.

Anatomical and physiological aspects of the mutual influence of circulatory hypoxia of the myometrium and non-progressive labour

Non-progressive labour occurs in almost 10% of deliveries and is a main reason for unplanned cesarean sections and operative vaginal births using obstetric forceps or vacuum extraction. This article describes the morphological transformation of the myometrium and uterine blood vessels that occurs during pregnancy. It is shown that the myometrium inevitably experiences hypoxia at the microstructural level during each normal or pathological labour. We analyzed recent studies of the mutual influence of myometrial hypoxia and labour dystocia. Experimental and clinical studies showed relationship between the pH values and lactate levels determined in the myometrium on its contractility. Further research is justified, including the study of the pH and lactate values in amniotic fluid in patients with non-progressive labor. Finally, that will allow for clarifying the conditions and timing of labour stimulation with oxytocin and identifying a group of patients for whom oxytocin administration is contraindicated or hopeless.

A Study the Water Quality Measuring Equipment with Automatic Sensor System

This paper studied the water quality in Dong Khoai Village, Xaythani District, Vientiane Capital, which is the primary water pumping location for agriculture. The area has a population of over 1735 citizens and cover more than 450 hectares. Common issue found in Markhiaw river. Stream is its toxicity to certain rice field, causing it inability to grow rice despite using fertilizer. Furthermore, this stream gives dissatisfaction odor, negatively affects people who get into the water for fishing and occasionally found death fish in the areas. In order to assess the water quality and disseminate the results to the public. Therefore, this study aims to investigate the creating of an automated sensor system for high precision water quality monitoring in the water. Four sensors; pH (hydrogen potential), EC (electro conductivity), TDS (total dissolved solid), and temperature are used in this procedure. The sensor system was tested, and build a small station uses solar energy and saves information into the SD card and available online by Blynk, and compare the test results with national environmental standards. The research revealed that, in comparison to the standard instrument S5 pro parameter, the measuring stations for the water quality values of all four sensors are accuracy value of 92.91% to 99.34%. Based on the information gathered over the course of two months, from February 13 and March 18, the pH value will be low, at 5. The pH value is high, at 11, between 13, 17 and 18 February 2024. These numbers are considered to be in the standard ranks. Regarding the dissolved solids in the water vary from 3 to 100 mg/L, and the electrical conductivity is between 100 and 180 µS/cm. They are also fall upon the National Environmental Standard. The Temperature value is high, at 40.81 ºC on 4 February 2024 and from 02 March 2024, the Temperature value will be low, at 24.4ºC.

Optimization of Copper-Ammonia-Sulfate Electrolyte for Maximizing Cu(I):Cu(II) Ratio Using pH and Copper Solubility

An investigation has been carried out to understand the solution chemistry of the Cu-NH−-SO4−2 system, focusing on the effect of pH on the solubility of copper in the solution and maximizing the Cu(I):Cu(II) ratio. A Pourbaix diagram for the Cu-N-S system has also been created using the HSC Chemistry software for a wide range of Cu-NH3 species, unlike most other studies that focused only on Cu(NH3)42+ and Cu(NH3)52+ (Cu(II)) as the dominant species. The Pourbaix diagram demonstrated that the Cu(I) exists as Cu(NH3)2+, while the Cu(II) species are present in the system as Cu(NH3)42+ and Cu(NH3)52+, depending upon the Eh and pH of the solution. Copper precipitation was observed in the electrolyte at pH values less than 8.0, and the precipitation behavior increased as the pH became acidic. The highest Cu(I):Cu(II) ratio was observed at higher pH values of 10.05 due to the higher solubility of copper at higher alkaline pH. The maximum Cu(II) concentration can be achieved at 4.0 M NH4OH and 0.76 M (NH4)2SO4. In the case of low pH, the highest Cu(I):Cu(II) ratio obtained was 0.91 against the 4.0 M and 0.25 M concentrations of NH4OH and (NH4)2SO4, respectively. Meanwhile, at high pH, the maximum Cu(I):Cu(II) ratio was 15.11 against the 0.25 M (NH4)2SO4 and 4.0 M NH4OH. Furthermore, the low pH experiments showed the equilibrium constant (K) K < 1, and the high pH experiments demonstrated K > 1, which justified the lower and higher copper concentrations in the solution, respectively.

Research and Evaluation of a Nanometer Plugging Agent for Shale Gas Horizontal Wells.

Due to the low permeability of shales, drilling fluid filtrate is very likely to intrude into the formation along the nanomicron pore joints of shale, leading to microfracture expansion and causing a well wall destabilization phenomenon. Based on the characteristics of the formation shale, a new nano plugging agent, styrene (St)/2-acrylamido-2-methylpropanesulfonic acid (AMPS)/ethyl acrylate (EA), was synthesized by emulsion polymerization using St, EA, and AMPS as reaction monomers. The analysis results using infrared spectroscopy and transmission electron microscopy showed that the product met the expected design. The particle size of the nano plugging agent St/AMPS/EA was mainly concentrated in the range of 50-130 nm. Thermogravimetric analysis revealed that the initial thermal decomposition temperature of St/AMPS/EA is 363.8 °C, indicating strong thermal stability. At a 3% concentration, the permeability of the mud cake decreased by 87.35%, and the maximum differential stress of the shale increased from 141.7 to 174.4 MPa. Stability analysis showed that the plugging agent maintained good plugging performance under various pH values and salinity conditions with fluid loss consistently around 3.2 mm. This nano plugging agent significantly improves wellbore stability, making it suitable for drilling in the Longmaxi Formation shale with developed microfractures, and provides valuable insights for similar formations.

Biochar affects organic carbon composition and stability in highly acidic tea plantation soil

Biochar amendments are effective in stabilizing soil aggregates and improving soil organic carbon (SOC) content. However, the effects of biochar on highly acidic soil and their relation with soil SOC stability remain understudied. The study aimed to investigate the impact of biochar on changes of aggregate distribution and SOC stability in a highly acidic tea plantation soils over an eight-year period. Soil samples were collected from plots with varying biochar application amounts (0, 2.5 t ha−1, 5 t ha−1, 10 t ha−1, 20 t ha−1 and 40 t ha−1). The content of SOC, iron bound organic carbon (OC-Fe), particulate organic carbon (POC), mineral-associated organic carbon (MAOC) and the functional group composition of SOC was analyzed. The results indicated that in the biochar application treatments, the value of soil pH, SOC, POC and MAOC contents were increased from 3.92 to 4.28, 6.68%–187.02%, 8.31%–66.78% and 13.07%–236.47% respectively, compared with CK, while the content of macro-aggregate (particle size>0.25 mm) and soil aggregates mean weight diameter (MWD) significantly increased with higher biochar application amounts. But dissolved organic carbon (DOC) and OC-Fe content exhibited downward trend, decreased from 2.43% to 6.97% and 4.18%–19.91%. Furthermore, aromatic-C levels increased, with increased biochar application amounts. The integration of biochar not only bolstered soil aggregate stability but also amplified the presence of aromatic-C, thereby enhancing the resilience of organic carbon in highly acidic tea garden soil (BC40 > BC20 > BC5>BC2.5 > BC10 > CK), with increases ranging from 6% to 47%. The principal component analysis and structural equation modeling identified soil pH, TN, SOC, POC, MAOC, R > 0.25 and MWD as key factors of soil organic carbon stability. These findings provide crucial insights into the mechanism underlying biochar's efficiency in fortifying organic carbon stability, particularly in the context of highly acidic soil.

Improving the sensory and chemical characteristics of functional yogurt fortified with cardamom extract (<i>Elettaria cardamomum</i> L.)

Abstract: This study aimed to assess the effects of aqueous cardamom extract on chemical and sensory qualities of yogurt fortified with cardamom extract. Four different concentrations of cardamom extract (100, 150, 200, and 250 μg.L-1) were incorporated into yogurt, along with a control group without adding cardamom. The moisture content, total protein, carbohydrates, pH, peroxide value, and sensory properties (taste, flavor, and smell) were evaluated. The results show that cardamom extract had no significant effect on the moisture, protein, or carbohydrate content of yoghurt when compared to the control. However, a drop in lipid, pH and peroxide value was seen in cardamom-fortified yoghurt, indicating enhanced lipid quality. Treatments supplemented with 200 and 250 μg.L-1 of extract showed the highest sensory scores. Overall, this study suggests that aqueous cardamom extract holds promise as a functional ingredient to improve yogurt quality and sensory qualities, potentially providing health benefits to consumers. Background: Yogurt is typically processed from cream, milk, or partially or completely skimmed milk, and may include additional ingredients such as vitamins, skimmed milk powder, lactose, lactalbumin, lactoglobulin, or modified whey. Cardamom encompasses two plant varieties, Elettaria and Amomum, belonging to the ginger family. These types are triangular in cross-section, bear seeds in bundles, and possess a thin outer membrane encasing black seeds. Whole milk yogurt was fortified with four different concentrations of aqueous cardamom extract. A control group of plain whole milk yogurt without additives was also prepared. The chemical and sensory properties of yogurt types were analyzed immediately after manufacturing and storage for 1, 3 and 7 days at 5 ±1 °C. Objective: This study aimed to explore the effects of aqueous cardamom extract on chemical and sensory qualities, which are critical for functional foods, of functional yogurt made from raw, whole cow's milk. Four concentrations (100, 150, 200, and 250 μg.L-1) of cardamom extract were incorporated into yogurt, along with a control group without added cardamom. The moisture content, total protein, carbohydrates, pH, peroxide value, and sensory properties (taste, flavor, and smell) were evaluated. Materials and Methods: Raw, whole cow's milk was used to make yogurt production in the laboratory. Five kilograms of raw, full-fat cow's milk was heated for 10 minutes at 90 °C, then cooled to 42 °C and divided into two parts. The first was divided into four fractions, each receiving a different concentration of cardamom extract: 100, 150, 200, and 250 μg/L, representing treatments T1, T2, T3, and T4, respectively. The second part remained untreated and served as the control treatment (C) for yogurt production.

Phthalate Esters in Water and Surface Sediments of Anambra River in Dry Season: Distribution and Human Health Risks Assessment

This study investigated phthalate ester (PAE) contamination in water and sediment samples due to their persistence and potential health risks as endocrine disruptors. Sediment analysis revealed pH ranged from 5.35 to 6.72, with total organic carbon (TOC) levels varying between 0.74% and 2.56%. Water pH values were within WHO guidelines (5.5–8.5), and turbidity levels ranged from 0.60 to 1.40 NTU. Phthalate concentrations in sediment revealed Monobutyl phthalate (MBP), Diethyl phthalate (DEP), Dipentyl phthalate (DPP), Butyl benzyl phthalate (BBP), Dibutyl phthalate (DBP), and Di(2-ethylhexyl) phthalate (DEHP). Sample SA exhibited the highest levels of MBP (0.40 mg/kg) and DEP (0.93 mg/kg). In water samples, MBP peaked at 0.01 mg/kg, while DEP reached 0.03 mg/kg, with DBP (0.07 mg/kg) and DEHP (0.08 mg/kg) also detected. Phthalate contamination in water remained below harmful thresholds. A health risk assessment calculated Chronic Daily Intake (CDI) and Hazard Quotients (HQ) for both children and adults. CDI results indicated higher risks for children, with DBP (2.20E-06 mg/kg/day) and DEHP (2.46E-06 mg/kg/day) showing the greatest concern. The HQ for children was highest for DBP (0.22), though still below the risk threshold. Adults exhibited lower CDI and HQ values, with minimal non-carcinogenic risk. These findings highlight the need for continued monitoring of phthalate pollution, especially given children’s heightened vulnerability.

Tyrosinase Inhibitory Activity of Crude Procyanidin Extract from Green Soybean Seed and the Stability of Bioactive Compounds in an Anti-Aging Skin Care Formulation

Green soybean (Glycine max L.) seed contains a high procyanidin content and high antioxidant activity. Moreover, ultrasound-assisted extraction (UAE) has proved to be advantageous in providing high extraction efficiency. Hence, this study aimed to extract procyanidins from green soybean seeds (GSSs) using UAE. This study also evaluated the inhibitory activities of tyrosinase and the cytotoxic effects of crude procyanidin extract. The extract exhibited maximum levels of bioactive components and antioxidant capacity when subjected to a temperature of 15 °C and an extraction time of 20 min. The crude procyanidin extract at a concentration of 10 mg/mL inhibited the tyrosinase enzyme by more than 60%, and the half-maximal inhibitory concentration (IC50) value obtained for the extract was 6.85 ± 0.81 mg/mL. This result was much greater than the IC50 value obtained for kojic acid (0.089 ± 0.08 mg/mL), which was used as a positive control. For the cytotoxicity assessment, the results indicated that the crude procyanidin extract showed no cytotoxicity and actually stimulated the growth of human skin fibroblast cells. More than 80% of the bioactive compounds (total phenolic content (TPC), total flavonoid content (TFC), procyanidin content (PC)) and antioxidant activities (DPPH and FRAP) of the crude extract powder were retained at 38.68 ± 0.01 mg GAE/g, 16.07 ± 0.01 mg CAE/g, 9.24 ± 0.01 mg PC/g, 359.8 ± 0.72 μM Trolox eq/g, and 1640 ± 2.86 μM Trolox eq/g, respectively, after 12 weeks of storage at 25 °C. The crude procyanidin extract powder was then included in a facial serum formulation and tested for pH value and physical evaluation. The stability of the crude procyanidin extract facial serum was shown to be greater for bioactive compounds and antioxidant activity when stored at a temperature of 4 °C than when stored at a temperature of 25 °C. These results suggest that the GSS extracts obtained via ultrasonication show promise for use in cosmeceutical formulations for whitening skincare products.

Effects of Vegetable Planting Ages on Community Structure of Ammonia-oxidizing Archaea and Ammonia-oxidizing Bacteria in Greenhouse Vegetable Fields

The ammonia oxidation process driven by microorganisms is a dominant source for nitrous oxide （N2O） emissions. Here, we examined the influence of greenhouse vegetable planting ages on soil ammonia-oxidizing archaea （AOA） and ammonia-oxidizing bacteria （AOB）, which is of great significance for assessing the soil quality status and greenhouse gas transformations. A field study was conducted at different times （1, 5, 10, and 20 a） in greenhouse vegetable soils of Gaoyi, Hebei Province. Chemical analysis and Illumina NovaSeq high-throughput sequencing were used to analyze the soil physicochemical properties and community structures and diversity of AOA and AOB. The variation in AOA and AOB communities and the driving factors in greenhouse soils at different ages were also investigated. The results showed that the contents of total nitrogen, organic matter, alkali-hydrolyzable nitrogen, available phosphorus, and available potassium first increased and then decreased with the prolongation of growth. The contents of nitrate nitrogen, ammonium nitrogen, and electrical conductivity first decreased and then increased with the prolongation of growth. The pH value of soils decreased with the prolongation of growth. The abundance and diversity index of AOA and AOB first decreased and then increased with the prolongation of growth. Nitrososphaeria, unclassified Thaumarchaeota, and Candidatus Nitrosocaldus were the dominant species of AOA, while Betaproteobacteria and Nitrosospira were the dominant species of AOB. The composition of the soil AOA community varied greatly compared to that of AOB with the prolongation of growth. Correlation analysis showed that the changes in soil nutrient factors had a significant correlation with AOA and AOB communities. Redundancy analysis indicated that ammonium nitrogen, alkali-hydrolyzable nitrogen, and nitrate nitrogen were key factors of AOA communities, while electrical conductivity, available potassium, and nitrate nitrogen were key factors for AOB. In summary, long-term planting of greenhouse vegetables significantly affected the abundance and composition of soil AOA and AOB communities. Our results provide a theoretical basis for further studies on the greenhouse gas transformation and microbial mechanisms of the nitrogen cycle in greenhouse soils.

Antibacterial effectors in Dictyostelium discoideum: specific activity against different bacterial species.

Dictyostelium discoideum is a phagocytic amoeba continuously eating, killing, and digesting bacteria. Previous studies have detected in D. discoideum cell extracts a bacteriolytic activity effective against Klebsiella pneumoniae bacteria. In this study, we characterized bacteriolytic activities found in D. discoideum cell extracts against five different bacteria (K. pneumoniae, Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus, and Bacillus subtilis). We first analyzed the bacteriolytic activity against these five bacteria in parallel over a range of pH values. We then measured the remaining bacteriolytic activity in D. discoideum kil1 and modA knockout mutants. We also performed partial fractionation of D. discoideum extracts and assessed activity against different bacteria. Together our results indicate that optimal bacteriolytic activity against different bacteria results from the action of different effectors. Proteomic analysis allowed us to propose a list of potential bacteriolytic effectors.IMPORTANCEMany antibacterial effectors have been characterized over the past decades, and their biological importance, mode of action, and specificity are often still under study. Here we characterized in vitro bacteriolytic activity in D. discoideum extracts against five species of Gram-negative and Gram-positive bacteria. Our results reveal that optimal lysis of different bacteria mobilizes different effectors. Proteomic analysis generated a list of potential bacteriolytic effectors. This work opens the way for future analysis of the role of individual effectors in living D. discoideum cells.

Efficacy of Acacia Gum Biopolymer in Strength Improvement of Silty and Clay Soils under Varying Curing Conditions

Acacia gum (AG), a polysaccharide biopolymer, has been adopted to improve the strength of three cohesive soils by subjecting them to diverse environmental aging conditions. Being a polysaccharide and a potentially sustainable construction material, the AG yielded flexible film-like threads after 48 h upon hydration, and its pH value of 4.9 varied marginally with the aging of the stabilized soils. The soil samples for the geotechnical evaluation were subjected to wet mixing and were tested under their Optimum Moisture Content (OMC), as determined by the light compaction method. The addition of AG modified the consistency indices of the soils due to the presence of hydroxyl groups in AG, which also led to a rise in OMC and reduction in Maximum Dry Unit weight (MDU). The Unconfined Compressive Strength (UCS) and California Bearing Ratio (CBR) were determined under thermal curing at 333 K as well as on the same day of sample preparation. The least performing condition of the soil’s CBR was evaluated under submerged conditions after allowing the AG-stabilized specimens to air-cure for a period of 1 week. The UCS specimens tested after 7 days were subjected to the initial 7 days of thermal curing at 333 K. A dosage of 1.5% of AG yielded the UCS of 2530 kN/m2 and CBR of 98.3%, respectively, for the low compressible clay (LCC) after subjecting the sample to 333 K temperature for 1 week. The viscosity of the AG was found to be 214.7 cP at 2% dosage. Scanning Electron Microscopy (SEM), Fourier Transform Infrared Spectroscopy (FTIR), and average particle size determination revealed the filling of pores by AG gel solution, adsorption, and hydrogen bonding, which led to improvements in macroproperties.

Effect of Dietary Supplementation with Different Proportions of Amaranthus hypochondriacus Stem and Leaf Powder on Intestinal Digestive Enzyme Activities, Volatile Fatty Acids and Microbiota of Broiler Chickens

Amaranthus hypochondriacus is rich in nutrients and represents a feed resource with significant potential. This experiment aimed to study the effects of different proportions of Amaranthus hypochondriacus stem and leaf powder (AHSL) on intestinal digestive enzyme activities, cecal volatile fatty acids, and the microbiota of broilers. A total of 288 one-day-old male broilers (Ross 308) were randomly assigned to the control diet group and the 3%, 6%, and 9% AHSL diet group for days 0–21. Subsequently, the 3%, 6%, and 9% AHSL diets were switched to 5%, 10%, and 15% AHSL diets for days 22–42. The results demonstrated that the dietary inclusion of AHSL significantly affected sucrase activity in the jejunal mucosa (p < 0.05). The 5% AHSL group exhibited the highest sucrase activity, followed by the control group, both of which showed significantly higher activity compared to the 10% and 15% AHSL groups (p < 0.05). The cecal pH in the 5%, 10%, and 15% AHSL groups was significantly lower than that in the control group (p < 0.05). The contents of acetate, propionate, butyrate, and valerate in the cecum of the 10% and 15% AHSL groups were significantly higher than those of the control group (p < 0.05). The addition of AHSL had no significant effect on the alpha diversity of cecum microorganisms. The relative abundance of Ruminococcaceae_UCG_005 and Lactonifactor was significantly higher in the 10% AHSL group compared to the control group, whereas the 15% AHSL group had a significantly higher relative abundance of Clostridium_sensus_tricto12, Peptoclostridium, Anaerofilum, and Peptococcaceae. In summary, the inclusion of 5% AHSL in the diet enhances sucrase activity in the jejunum of broilers, while 10% or 15% AHSL increases the volatile fatty acid content and reduces the pH value in the cecum, without adverse effects on the cecal microbiota.

The Effect of Sodium Hexametaphosphate on the Dispersion and Polishing Performance of Lanthanum-Cerium-Based Slurry.

A lanthanum-cerium-based abrasive composed of CeO2, LaOF, and LaF3 was commercially obtained. The effect of sodium hexametaphosphate (SHMP) on powder dispersion behavior was systematically investigated using the combined techniques of liquid contact angle, turbidity, zeta potential (ZP), scanning electron microscopy (SEM), powder X-ray diffraction (XRD) combined with Rietveld refinements, X-ray photoelectron spectroscopy (XPS), and polishing tests. The results indicated that the addition of 0.5 wt.% SHMP dispersant to the 5 wt.% lanthanum-cerium-based slurry produced the most stable suspension with a high turbidity of 2715 NTU and a low wetting angle of 45°. The as-obtained slurry displayed good surface polishing quality for K9 glass, with low surface roughness (Ra) of 0.642 and 0.515 nm (in the range of 979 × 979 μm2) at pH = 6 and 11, respectively, which corresponds to the fact that it has local maximum absolute values of ZP at these two pH values. SEM images demonstrated that after appropriate grafting of SHMP, the particle aggregation was reduced and the slurry's dispersion stability was improved. In addition, the dispersion mechanism was explained based on the principle of complexation reaction, which reveals that the dispersant SHMP can increase the interparticle steric hindrance and electrostatic repulsions. In an acidic environment, steric hindrance dominates, while electrostatic repulsion prevails under alkaline conditions. As expected, this polishing slurry may find potential applications in manufacturing optical devices and integrated circuits.

Prediction of Flotation Deinking Performance: A Comparative Analysis of Machine Learning Techniques

Flotation deinking is one of the most widely used techniques for the separation of ink particles from cellulose fibers during the process of paper recycling. It is a complex process influenced by a variety of factors, and is difficult to represent and usually results in models that are inconvenient to implement and/or interpret. In this paper, a comprehensive study of several machine learning methods for the prediction of flotation deinking performance is carried out, including support vector regression, regression tree ensembles (random forests and boosting) and Gaussian process regression. The prediction relies on the development of a limited dataset that assumes representative data samples obtained under a variety of laboratory conditions, including different reagents, pH values and flotation residence times. The results obtained in this paper confirm that the machine learning methods enable the accurate prediction of flotation deinking performance even when the dataset used for training the model is limited, thus enabling the determination of optimal conditions for the paper recycling process, with only minimal costs and effort. Considering the low complexity of the Gaussian process regression compared to the aforementioned ensemble models, it should be emphasized that the Gaussian process regression gave the best performance in estimating fiber recovery (R2 = 97.77%) and a reasonable performance in estimating the toner recovery (R2 = 86.31%).

Integrating Pt single atoms and Mo into PtNi/C through Mo doping-displacement synchronisation strategy for enhanced HER at all pH values

This paper proposes a Mo doping-displacement synchronization strategy to integrate Pt SAs and Mo atoms into PtNi/C, synthesizing Pt SAs/Mo-doped PtNi octahedra/carbon support catalyst (Pt SAs/Mo-PtNi/C). In this approach, Mo atoms are doped into PtNi alloy octahedra and displace some Pt atoms, forming Mo-PtNi octahedra. Importantly, the substituted Pt atoms can adhere to carbon substrate, creating Pt SAs. Pt SAs/Mo-PtNi/C exhibits lower overpotentials (38, 59, and 110 mV at 10 mA cm−2) and smaller Tafel slopes (44, 51, and 139 mV dec-1) in acidic, alkaline, and neutral environments. Additionally, the electron pathway of Mo-PtNi → Pt SAs/C has been confirmed, and Pt SAs/Mo-PtNi/C exhibits an optimized hydrogen adsorption energy (ΔGH*=-0.29 eV). Furthermore, catalyzed by Pt SAs/Mo-PtNi/C, the H-O bond length of H2O extends to 1.11 Å and the bond angle reduces to 102.741°, directly confirming that the Pt SAs and doped Mo could facilitate H-O bond breaking. The proposed Mo doping-displacement synchronization strategy not only simplifies the fabrication process of Pt SAs catalyst, but also improves its durability and activity across a wide pH range, thereby potentially advancing hydrogen production technologies.

Combined optical measurement of dissolved oxygen tension (DOT), pH value, biomass and viscosity in shake flasks

Shake flasks are widely spread in microbial process development. Characterization of the processes by manual offline sampling is time-consuming, highly laborious and a contamination risk. Online monitoring of key parameters would provide deeper insights, while saving time and effort. In this study, a device for optical online monitoring of dissolved oxygen tension (DOT), biomass, pH value and viscosity in shake flasks is presented. DOT measurement relies on fluorescent oxygen sensitive nanoparticles. The fluorescence intensity signal of the nanoparticles is used to trigger the DOT and scattered light measurements inside the rotating bulk liquid. The scattered light signal (610 – 630 nm) can be correlated to offline measured optical density OD600, even at elevated viscosity. The pH value is monitored online by using pH sensor spots, fixed inside the shake flasks. The shift of the angle of the bulk liquid Θ-Θ0 is correlated to the offline measured viscosity. Detection of the leading edge of the bulk liquid, necessary for viscosity measurement, can be performed either using the fluorescence intensity signal of the oxygen nanoparticles or the scattered light signal.