Optimal Concentration Research Articles

Rapamycin Increases the Development Competence of Yak (Bos grunniens) Oocytes by Promoting Autophagy via Upregulating 17β-Estradiol and HIF-1α During In Vitro Maturation

High-quality oocyte production strategies play an important role in animal-assisted reproductive biotechnologies, and rapamycin (Rap) has been commonly used to increase the development potential of mammalian oocytes. The purpose of this study is to evaluate the effects and possible molecular mechanisms of rap on the maturation of yak oocytes. Different concentrations of Rap were supplemented during in vitro maturation (IVM) of yak oocytes. The maturation rates of oocytes and development rates of parthenogenetically activated embryos were assessed. The levels of 17β-estradiol (E2) were detected via ELISA, and the expression of autophagy-related factors, steroidogenic enzymes, and HIF-1α was detected via qRT-PCR, western blotting, and fluorescence microscopy, respectively. In addition, the impacts of E2 and HIF-1α on Rap-mediated oocyte autophagy were investigated by investigating the activities of E2 and HIF-1α. Our results showed that 0.1 nM Rap substantially enhanced the developmental ability of yak oocytes. In this group, the levels of E2, CYP19A1, CYP17A1, and autophagy-related factors were also significantly increased, and the expression of ATG5 and BECN1 in subsequent embryos was also increased. Further analysis revealed that Rap tends to enhance the development competence of yak oocytes and that the levels of autophagy-related factors are reduced when the activity of E2 or HIF-1α is inhibited. Furthermore, the levels of E2, CYP19A1, and CYP17A1 were downregulated when the activity of HIF-1α was inhibited, and the levels of HIF-1α were also significantly reduced by the estrogen receptor antagonist G15. Nevertheless, the levels of CYP11A1 mRNA in mature yak COCs were not significantly different among these groups, a phenomenon which implies that the levels of E2 were not correlated with the CYP11A1 content in yak COCs. There was an increasing tendency for the development competence of yak oocytes at the optimum concentration of Rap during IVM. The potential underlying mechanism is that Rap can activate autophagy and upregulate the levels of E2 and HIF-1α in mature oocytes. Additionally, the levels of both E2 and HIF-1α are regulated by each other and involve Rap-regulated autophagy in oocytes.

Urea enhances the yield and quality of bio-oil produced from corncob through pyrolysis

As global demand for fossil fuels rises amidst depleting reserves and environmental concerns, exploring sustainable and renewable energy sources has become imperative. This study investigated the pyrolysis of corncob, a widely available agricultural waste, using urea as a catalyst to enhance bio-oil production. The aim was to determine the optimum urea concentration and pyrolysis temperature for bio-oil yield from corncob. A series of experiments were conducted at varying temperatures (350 °C, 400 °C, and 450 °C) and urea concentrations (0%, 5%, 10%, 15%, and 20%) to assess their impact on bio-oil yield, chemical composition, and energy content. Fourier Transform-Infrared Spectroscopy, Gas Chromatography-Mass Spectrometry (GC–MS), Ultimate Analysis, and High Heating Value (HHV) analyses were employed to evaluate the quality of bio-oil produced. Results indicate that a 10% urea concentration at 400 °C improves bio-oil yield from 49.33 to 54.66%. FT-IR analysis revealed enhanced absorption in key functional group regions, including O–H, N–H, C–H, C=O, and C–O, for bio-oil treated with 10% urea compared to untreated bio-oil. Ultimate analysis indicates that urea treatment improved bio-oil quality by increasing carbon (84.80–86.40%), nitrogen (2.29–2.68%), and oxygen (7.22–8.31%) contents while reducing hydrogen (5.09–2.38%) and sulfur (0.62–0.20%) contents, with improvement in the HHV from 36.12 to 37.12 MJ/kg. GC–MS analysis further revealed the presence of nitrogenous compounds, notably siloxanes in the bio-oil produced with urea infusion. This research highlights the potential of urea-catalyzed pyrolysis as a viable method for converting corncob into high-energy bio-oil, offering a promising alternative to traditional fossil fuels while addressing sustainability and environmental impact challenges.

Comparative metabolomic analysis of Haematococcus pluvialis during hyperaccumulation of astaxanthin under the high salinity and nitrogen deficiency conditions.

Revealing the differences of metabolite profiles of H. pluvialis during hyperaccumulation of astaxanthin under the high salinity and nitrogen deficiency conditions was the key issues of the present study. To investigate the optimum NaCl and NaNO3 concentration and the corresponding metabolic characteristic related to the astaxanthin accumulation in H. pluvialis, a batch culture experiment was conducted. The results indicated that 7.5g·L- 1 and 0g·L- 1 (nitrogen deficiency) were the optimum NaCl and NaNO3 levels for the astaxanthin accumulation respectively, under which the highest astaxanthin contents reached up to 7.51mg·L- 1 and 5.60mg·L- 1. A total of 132 metabolites were identified using LC-MS/MS technique, among which 30 differential metabolites with statistical significance were highlighted. Subsequently, 18 and 10 differential metabolic pathways in the high salinity (HS) and nitrogen-deficient (ND) treatments were extracted and annotated respectively. The values of Fv/Fm, Yield and NPQ were all at the highest level in the ND group during the experiment. The levels of the metabolites in the ND group were almost lower than those both in the control (CK) and HS group, while which in the HS group were substantially at the higher or close levels compared to the CK group. Finally, 7 metabolic markers related to the astaxanthin accumulation were highlighted in the HS and ND group respectively. L-Proline, L-Aspartate, Uridine 5'-monophosphate (UMP), Succinate, L-2-Hydroxygluterate, L-Valine and Inosine 5'-monophosphate (IMP) were identified as the metabolic markers in the HS group, whose fold change were 0.85, 4.14, 0.31, 0.66, 3.10, 1.32 and 0.30. Otherwise, the metabolic markers were Glyceric acid, Thymine, sn-Glycerol 3-phosphate, Glycine, Allantoic acid, L-Valine and IMP in the ND group, with the fold change 0.23, 2.11, 0.38, 0.41, 0.50 and 2.96 respectively. The results provided the comparative metabolomic view of astaxanthin accumulation in H. pluvialis under the different cultivation conditions, moreover showed a novel insights into the astaxanthin production.

Design and Synthesis of Crystalline Al-Doped TiO2 Buffer Layers for Enhancing Energy Conversion Efficiency of New Photovoltaic Devices

Perovskite solar cells (PSCs) characterized by high energy conversion efficiency (ECE) and low manufacturing costs, exhibit promising potential for commercialization in the near term. For commercialization, it is very important to prevent the decomposition of perovskite by ultraviolet (UV) radiation in the air environment. Also, the mesoscopic architecture of PSCs presents considerable opportunities for the solar cell industry, offering potential for recycling of spent photocatalytic materials such as TiO2, and exploration of new energy resources. To solve these problems, therefore, this study introduces a strategy to mitigate these challenges using a crystalline Al-doped TiO2 buffer layer as the electron transport layer (ETL) in conjunction with a mesoporous TiO2 layer in the fabrication of PSCs. Among various Al concentrations in the crystalline Al-doped TiO2 buffer layer fabricated via spin-coating, an optimum concentration of 7 mol% Al yielded the highest cell performance in the specific perovskite solar cell structure. These solar cells exhibited an impressive ECE of 11.87%, representing a substantial enhancement of nearly double the ECE (6.37%) achieved with the conventional ETL. This remarkable improvement can be attributed to the passivation effect of the newly developed ETL, which combines a crystalline Al-doped TiO2 buffer layer with a mesoporousTiO2 layer. Electrochemical impedance spectroscopy (EIS) analysis was performed in conjunction with theoretical calculations of charge transport parameters to substantiate this claim.

A photosynthesis‐derived bionic system for sustainable biosynthesis

“Cell factory” strategy based on microbial anabolism pathways offers an intriguing alternative to relieve the dependence on fossil fuels, which are recognized as the main sources of CO2 emission. Typically, anabolism of intracellular substance in cell factory requires the consumption of sufficient reduced nicotinamide adenine dinucleotide phosphate (NADPH) and adenosine triphosphate (ATP). However, it is of great challenge to modify the natural limited anabolism and to increase the insufficient level of NADPH and ATP to optimum concentrations without causing metabolic imbalance. Inspired by the natural photosynthesis process in which NADPH and ATP can both be produced through the coupled electron‐proton transfer processes driven by sunlight, herein we designed a light‐driven bionic system composed of three modules including photo‐induced electron module, electron transfer channel module and proton gradient module. The proposed strategy of light‐driven bionic system enables for achieving simultaneous and controllable supplies of NADPH and ATP, thus facilitating both highly efficient CO2 fixation and biomanufacturing. The proposed light‐driven bionic system design strategy in this work might pave new sustainable ways for reducing power and energy regeneration to optimize microbial metabolism, offering intriguing alternatives for CO2 emission reduction and high value‐added chemical biomanufacturing.

A photosynthesis-derived bionic system for sustainable biosynthesis.

"Cell factory" strategy based on microbial anabolism pathways offers an intriguing alternative to relieve the dependence on fossil fuels, which are recognized as the main sources of CO2 emission. Typically, anabolism of intracellular substance in cell factory requires the consumption of sufficient reduced nicotinamide adenine dinucleotide phosphate (NADPH) and adenosine triphosphate (ATP). However, it is of great challenge to modify the natural limited anabolism and to increase the insufficient level of NADPH and ATP to optimum concentrations without causing metabolic imbalance. Inspired by the natural photosynthesis process in which NADPH and ATP can both be produced through the coupled electron-proton transfer processes driven by sunlight, herein we designed a light-driven bionic system composed of three modules including photo-induced electron module, electron transfer channel module and proton gradient module. The proposed strategy of light-driven bionic system enables for achieving simultaneous and controllable supplies of NADPH and ATP, thus facilitating both highly efficient CO2 fixation and biomanufacturing. The proposed light-driven bionic system design strategy in this work might pave new sustainable ways for reducing power and energy regeneration to optimize microbial metabolism, offering intriguing alternatives for CO2 emission reduction and high value-added chemical biomanufacturing.

Effective removal of heavy metal ions (Pb, Cu, and Cd) from contaminated water by limestone mine wastes

Limestone mining waste and its derived CaO were checked as an adsorbents of pb2+, Cu2+, and Cd2+ ions from water solution. The characterization of Limestone and calcined limestone was studied by using X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA), Scanning Electron Microscope (SEM), and Surface area measurements (BET). The optimum conditions of sorbent dosage, pH, initial concentration, and contact time factors were investigated for pristine limestone and calcined limestone absorbents. The results indicate that the optimum initial concentrations of (Ci) were 1200, 500, and 300 ppm for Pb, Cu, and Cd, respectively, using calcined limestone adsorbent, while using the pristine limestone adsorbent, the corresponding optimum initial concentrations were 700, 110, and 50 ppm. In the ternary system sorption, the results indicated that the selectivity sequence of the studied metals by limestone can be expressed as Pb2+ > Cd2+ > Cu2+, while calcined limestone exhibits a higher selectivity for Pb2+ compared to Cu2+ and Cd2+. Hence, various adsorption isotherm and kinetic models were examined to explore different patterns and behaviors of adsorption. So, the results indicate that calcined limestone has great potential for eliminating cationic heavy metal species from industrial water solutions.

Optimization of green tea extract, rosemary extract, and rice bran in multifunctional bread: A concept for reduction of acrylamide and phytic acid.

This research aimed to produce a multifunctional bread by adding hydrothermally processed rice bran (RB), green tea extract (GTE), and rosemary extract (RE). In the first step, hydrothermal processing was used to reduce the amount of phytic acid in RB, which decreased by 55%. Based on the acrylamide amount, texture profile analysis, and color parameters, 3% RB was selected as the optimum concentration in the bread formulation. The acrylamide amount in the RB-fortified bread showed a significant (p<0.05) reduction trend with the addition of GTE and RE. So the lowest amount of acrylamide concentration was reported in the sample containing 1.5% GTE (17.18ppb). The addition of GTE and RE significantly (p<0.05) decreased the hardness value of bread samples. However, the cohesiveness, springiness, and adhesiveness parameters of bread samples were significantly (p<0.05) increased by the addition of GTE and RE. In addition, the fortified breads with 0.1% RE and 1.5% GTE exhibited the lowest and highest ΔE values, respectively. The addition of GTE and RE caused no adverse effect on the sensory properties of the RB-fortified bread. In conclusion, the combination of RB, GTE, and/or RE is an effective strategy for providing health benefits as well as reducing acrylamide formation in this food.

Enhanced biomass production and bioelectricity generation in microalgae culture medium using electrode pairings

Microalgae-based biofuel production offers promising avenues for sustainable energy generation. However, optimizing microalgae culture conditions for enhanced biomass production and bioelectricity generation remains challenging. This study addresses this problem by investigating the efficacy of different electrode pairings immersed in a microalgae culture medium. Two electrode pairs, Al-Fe and Cu-Zn were evaluated for their impact on microalgae growth and bioelectricity production. The optimum biomass concentration obtained was 1.204 g/L of Al-Fe electrodes with a lipid content of 15.1% and bioelectricity generation of 0.36V. The results demonstrated that Al-Fe electrodes induced high biomass concentration and lipid content in microalgae culture, facilitating biodiesel production. Conversely, Cu paired with Zn electrode promoted microalgae growth with elevated bioelectricity generation with 0.95V. This research sheds light on the potential of tailored electrode pairings to optimize microalgae culture conditions for dual-purpose biofuels and bioelectricity production, contributing to the advancement of sustainable energy technologies. It was recommended, among others, that further exploration of diverse electrode pairings within microalgae cultured medium could unveil additional effective strategies for optimizing biomass production and bioelectricity generation.

Enhanced functionalities in flexible poly (vinylidene fluoride-trifluoroethylene)/cerium oxide doped sodium bismuth titanate [P(VDF-TrFE)/NBT-CeO2] ceramic polymer composite films: A comprehensive investigation of piezoelectric, pyroelectric, and ferroelectric properties

In the pursuit of innovative smart polymer piezoelectric ceramic composites, we present a thorough examination of the physical, structural, and polarization characteristics of a novel flexible polymer ceramic composite comprising sodium-bismuth titanate (NBT) doped with 0.6 mass % CeO2 as ceramic fillers embedded in a poly (vinylidene fluoride-trifluoroethylene) (P(VDF-TrFE)) polymer matrix. The incorporation of these fillers serves to increase both the mechanical strength and functional attributes of the resulting polymer-ceramic composites. Various volume percentages of ceramic fillers were employed, and the experimental effective dielectric permittivity results were systematically fitted to established theoretical models, including Maxwell, Clausius−Mossotti, Furukawa, and effective medium theory (EMT). Our findings reveal that the composite films exhibit exceptional piezo-, pyro-, and ferroelectric properties when compared to the pristine P(VDF-TrFE) copolymer. The optimum concentration of NBT-0.6 CeO2 filler was determined to be 0.2 vol fraction resulting in a remarkable enhancement of the key parameters. Specifically, the pyroelectric coefficient increased from 32 μC/m2K to 43 μC/m2K (a ∼35 % increment), remnant polarization surged from 80 mC/m2 to 166 mC/m2 (an impressive ∼110 % increment), and the piezoelectric constant (d33) elevated from −38 pC/N to 49 pC/N (a substantial ∼30 % increment). These findings signify the potential of these optimized samples for applications in high energy density capacitors and/or highly integrated and intelligent piezoelectric devices. This comprehensive investigation not only advances our understanding of the synergistic effects within polymer-ceramic composites but also underscores the potential of the proposed material system for practical applications, providing valuable insights for the development of advanced multifunctional materials.

Experimental evaluation of nanoclay assisted water based EOR method

Recently, one of the most applicable nanoparticles (NPs) is nanoclay that is especially used in drilling to enhance the rheology of the drilling fluids. However, the experimental analysis of nanoclay in enhanced oil recovery (EOR) applications was rarely investigated. The main goal of this study is to find an ideal nanoclay concentration for the EOR fluid in two steps. The first is nanoclay stability that focus on finding the most stable nanofluid and the second is interfacial tension (IFT) and contact angle (CA) measurement that concentrate on selecting the best EOR fluid. Experiments such as nanofluid preparation, nanofluid stability, Dynamic Light Scattering (DLS), Zeta potential, X-Ray Diffraction (XRD) and Scanning Electron Microscope (SEM) analysis, clay swelling tests, CA and IFT measurements were performed for this purpose. All of the experiments were done in ambient pressure and temperature. The core samples and thin sections that are used in the experiments are oil-wet in nature. Results of the experiments confirm the stability of nanoclay in presence of the selected surfactant Cetyl Trimethyl Ammonium Bromide (CTAB) employed in the study. On the other hand, nanoclay has the ability to reduce the IFT nearly 5 dyne/cm, and also the combination of nanoclay and CTAB modify CA in the order of 10. It is founded that the optimum concentration for EOR fluid during the experiments is 0.5 weight% (wt%) CTAB and 0.1 wt% nanoclay.

Examining the optimum concentrations of CuO, ZnO, TiO2, and GO in porous asphalt for urban surface runoff using response surface Methodology

Examining the optimum concentrations of CuO, ZnO, TiO2, and GO in porous asphalt for urban surface runoff using response surface Methodology

Mechanical and Microstructural Properties of Geopolymer Incorporated with Copper Slag Activated by Phosphoric Acid

Abstract In this study, fly ash (FA), a kind of aluminosilicate precursor, is activated by phosphoric aid (H3PO4) to produce a silico-aluminophosphate geopolymer. This study aims to assess the viability of substituting M-sand with varying proportions, ranging from 0 % to 100 %, of copper slag in geopolymer mortar. The alkaline-activated geopolymer mortar was produced by using sodium hydroxide (NaOH) and sodium silicate. The phosphoric acid-activated geopolymer (PGP) samples were produced by changing parameters such as the liquid/solids (L/S) ratio, curing temperature, and molarity of H3PO4. The L/S ratios examined were 0.8, 0.9, and 1.0, whereas the molarities of H3PO4 employed were 8 M, 10 M, and 12 M. An assessment was conducted on the compressive strength, scanning electron microscope (SEM) examination, Fourier-transform infrared spectroscopy, X-ray diffraction, and energy dispersive X-ray analysis of PGP. The findings indicated a positive correlation between the compressive strength and the molarity, whereas a negative correlation was observed between the compressive strength and the L/S ratio. The highest compressive strength obtained was 41.1 MPa, which occurred when the optimum concentration of H3PO4 was 10 M. The formation of the P-O-Si-O-Al-O polymeric structure contributed to the strength of the phosphoric acid-based FA geopolymer. The SEM images demonstrated that the geopolymer samples containing 100 % copper slag and a L/S ratio of 0.9 exhibited a compact and uniform microstructure, resulting in enhanced strength characteristics.

USE OF STABILIZING ADDITIVES FOR TARGETED MODIFICATION AND HARDENING OF Nd2Zr2O7 CERAMICS

This paper presents the results of experimental work related to the preparation of Nd2Zr2O7 ceramics stabilized by Y2O3, the choice of which is due to the great prospects for their use as materials for inert matrices of dispersed nuclear fuel. During the conducted experiments aimed at determining the effectiveness of the influence of stabilizing additives in the form of Y2O3 on the change of structural and strength parameters of Nd2Zr2O7 ceramics it was found that the increase in the concentration of stabilizing additives above 0.1 M leads to the formation of inclusions in the structure in the form of Y2Zr2O7 grains, the formation of which is associated with the effects of polymorphic transformations in zirconium dioxide during high-temperature annealing. It was determined that the substitution of zirconium cations by yttrium cations leads to an increase in the concentration of oxygen vacancies in ceramics composition, the change in the concentration of which is also associated with phase transformations in the structure, arising at high concentrations of stabilizing dopant. At the same time, the optimum concentration of stabilizing additives is the concentration of 0.15 M, at which the ratio of structural and strength parameters has optimum values, determining their potential use as materials of inert matrices of dispersed nuclear fuel with high strength characteristics.

Effects of immersion bathing in Lactobacillus plantarum CLY-05 on the growth performance, non-specific immune enzyme activities and gut microbiota of Apostichopus japonicus.

In order to study the optimal use of Lactobacillus plantarum in sea cucumber (Apostichopus japonicus), 49 days feeding trial was conducted to determine the influence of immersion bathing in different concentrations of Lactobacillus plantarum CLY-05 on body weight gain rate and non-specific immune activities. The potential effect of CLY-05 on gut microbiota was also analyzed during the immersion bathing at the optimum concentration. The results showed that the body weight growth rate of all bathing groups was higher than that of control. The highest specific growth rate (4.58%) and weight gain rate (25.35%) was achieved at the bacterial concentration of 1×103 CFU/mL. The activities of non-specific immune enzymes (ACP, AKP, SOD and LZM) of all bathing groups increased after immersion bathing, and the enzyme activities of groups bathed with the bacterium at 1×103 and 1×104 CFU/mL reached the highest. Therefore, 1×103 CFU/mL was considered as the optimum concentration of L. plantarum CLY-05 for A. japonicus pond culture. The results of gut microbiota analysis showed that the gut microbiota changed with the addition of L. plantarum CLY-05, and the richness and diversity of the gut microbiota peaked on day 14 and day 21, respectively. The correlation analysis revealed that the non-specific immune enzyme activities were significantly correlated to some gut bacteria (in the phyla Proteobacteria, Firmicutes) after immersion bathing in L. plantarum CLY-05. These findings provide the theoretical foundation for probiotic application in sea cucumber farming.

Optimization of Antioxidant Extraction from Avocado Peel and its Antibacterial Properties and Potentials in Food Products

Avocado peel, with a high proportion of bioactive compounds, is usually discarded as waste. Preliminary study was carried out to determine the most suitable solvent (out of acetones, water, ethanol and methanol) for extraction of antioxidants from avocado peel. Free radical scavenging activity (DPPH), Ferric reducing antioxidant (FRAP) and total phenolic content (TPC) were evaluated as responses. The oxidative stability of cooked ground beef, fish, oil samples (soybean, palm, groundnut) treated with optimum concentration of avocado peel ethanol extract (APE) was evaluated over time using standard procedures. Although methanol had a significantly higher (p&lt;0.05) TPC and FRAP, it was not significantly different (p&gt;0.05) in DPPH from ethanol; hence ethanol was selected based on its known low-toxicity. Results indicated that process variables with. Optimum solvent concentration, extraction time and extraction temperature with the highest desirability index of 0.868 was 80 %, 90 min and 60 օC respectively. Cooked ground beef and fish treated with &gt; 0.3 % APE resulted in a more significant reduction (p&lt;0.05) in pH values than the positive control (0.1 % BHT). However, there was no significant difference (p&gt;0.05) in TBARS in both ground beef and fish samples treated with 0.5% APE and the positive control. Similarly, treatment with APE significantly reduced peroxide value (PV) in order groundnut oil&gt;soybean oil&gt; and palm oil and acid value (AV) in the order soybean oil&gt; groundnut oil &gt; palm oil used in this study. The minimum inhibitory concentration of APE was 20 mg/ml for S. aureus, 10 mg/mL for S. typhi and E. coli. The preservative effect of APE increased with increase in concentration of APE. Thus, its potentials in preservation of food products.

(Ligno)Cellulose Nanofibrils and Tannic Acid as Green Fillers for the Production of Poly(vinyl alcohol) Biocomposite Films.

This study compared the use of cellulose nanofibrils (CNF) and lignocellulose nanofibrils (LCNF) in different concentrations to reinforce the poly(vinyl alcohol) (PVA) matrix. Both nanofillers significantly improved the elastic modulus and tensile strength of PVA biocomposite films. The optimum concentration of CNF and LCNF was 6% relative to PVA, which improved the tensile strength of the final PVA biocomposite with CNF and LCNF by 53% and 39%, respectively, compared to the neat PVA film. The addition of LCNF resulted in more elastic films than the addition of CNF to the PVA matrix. The elongation at break of the PVA biocomposite with 2% of LCNF was more than 100% higher than that of the neat PVA film. The integration of tannic acid (TA) into the PVA-LCNF system resulted in antioxidant-active and more water-resistant PVA biocomposites. The three-component biocomposite films with 2 and 6% LCNF and 10% TA exhibited a more than 20° higher contact angle of the water droplet on the surfaces of the biocomposite films and absorbed more than 50% less water than the neat PVA film. New formulations of biocomposite films have been developed with the addition of LCNF and TA in a polymeric PVA matrix.

Determination of size and particle number concentration of metallic nanoparticles using isotope dilution analysis combined with single particle ICP-MS to minimise matrix effects.

Single particle inductively coupled plasma mass spectrometry (SP-ICP-MS) is a powerful tool for metallic nanoparticle (NP) characterisation in terms of concentration and, taking into account several assumptions, also size. However, this technique faces challenges, such as the intrinsic matrix effect, which significantly impact the results when analysing real complex samples. This issue is critical for the calculations of key SP-ICP-MS parameters ultimately altering the final outcomes. Novel analytical approaches with high metrological quality such as isotope dilution analysis (IDA) can overcome these limitations by improving signal discrimination in challenging SP-ICP-MS scenarios. This alternative has mainly been applied for NP size characterisation but remains underexplored in modern ICP-MS and SP set-ups. Thus, the implementation of a revised version of IDA-SP-ICP-MS, including recent advances in quadrupole ICP-MS and SP data processing, which enables reliable NP sizing and counting, would be of utmost interest. In this work, this combination using the species-unspecific IDA mode has been investigated as an alternative to tackle matrix effect caused by complex matrices with platinum NPs as a case study. The optimum ionic tracer concentration has been evaluated for different PtNP sizes, resulting in a range of 500 to 1000ng L-1 due to differences in the mean NP signal. A valuable in-house spreadsheet for the data treatment has also been developed. The successful applicability of the methodology for determining the size and particle number concentration of 30 and 50nm PtNPs has been demonstrated not only in environmental samples (synthetic and natural seawater), but also, for the first time, in biological matrices such as cell culture media and human urine.

Standardization of Sucrose Concentration in Micropropagation of Valuable Aquascape Plant Echinodorus grisebachii

Aims: To standardize the optimum sucrose concentration in shooting and rooting medium in micropropagation of valuable aquascape plant Echinodorus grisebachii. Study Design: CRD. Place and Duration of Study: Department of Floriculture and Landscaping, College of Agriculture Vellayani 2022-2024. Methodology: In this study, eight treatments were evaluated separately for their effectiveness in shooting and rooting medium. For the shooting medium, 2 mgL-1 BAP (6-Benzylaminopurine) and 3 sucrose concentrations (10, 20,30) gL⁻¹ were used in the MS medium and half-strength MS medium. For rooting medium 3.0 mgL⁻¹ IBA (Indole-3-butyric acid), three concentrations of sucrose as in shooting medium were tried. Results: The result of the study showed that out of 8 treatments tried for shooting medium MS + 2mgL-1 + 30 gL⁻¹ sucrose was best resulted in Shoot initiation (100 %), Minimum days to shoot emergence (6.17), Maximum number of shoots (9.83), Longest shoot (10.33) and maximum number of leaves (31). For rooting medium ½ MS + 3.0 mgL⁻¹ IBA + 30 gL⁻¹ sucrose was best resulted in minimum number of days in root emergence (12.58) and maximum root initiation percentage (99.25). Conclusion: An effective concentration of sucrose was standardized for Echinodorus grisebachii.

Effects of Vitamins as Green Inhibitors on the Surface of Steel Bars in Chloride-Polluted Simulated Concrete Pore Solution: Experimental, Characteristic Analysis, and Theoretical Calculation.

This study evaluates the effects of vitamins B1 (VB1), B6 (VB6), B3 (VB3), and C (VC) as green corrosion inhibitors for steel bars in a chloride-polluted simulated concrete pore (SCP) solution. Electrochemical tests demonstrated that VB6 achieves the highest corrosion inhibition efficiency (IE%) of 92.86%, and the IE% of VB1 and VC are 91.96 and 91.51%, respectively, while VB3 shows the least effectiveness of 83.49% at their respective optimum concentrations. Scanning electron microscopy revealed that vitamin treatment significantly improves the surface morphology, enhancing smoothness. Energy dispersive X-ray spectroscopy confirmed the presence of protective molecular layers and precipitated calcium (Ca) on the steel surface, indicating effective adsorption. X-ray photoelectron spectroscopy revealed that vitamin interacts with iron (Fe) through chemisorption and physisorption, contributing to the formation of protective FeOOH compounds. Moreover, it also suggests that the main component of precipitated Ca is protective calcium carbonate (CaCO3). Density functional theory calculations showed that vitamins adhere to the surface of γ-FeOOH through hydrogen bonds. These findings underscore the potential of vitamins as effective green inhibitors in corrosion prevention applications.