Potential Values Research Articles

The indirect global warming potential of methane oxidation in the IPCC’s sixth assessment report

Abstract Greenhouse-gas emission (GHG) metric values for methane in the sixth assessment report by the Intergovernmental Panel on Climate Change (IPCC) include the indirect effect associated to the oxidation of methane to CO2. An analysis of the figures provided by the IPCC reveals they assume that in average 75% of methane is ultimately oxidized to CO2, while the remaining 25% is converted to intermediate degradation products, most notably formaldehyde, which are removed from the atmosphere via wet and dry deposition and treated by the IPCC as a potential carbon sink in terrestrial and aquatic ecosystems. In this short article we present a critique to this assumption, based on existing knowledge about the environmental fate of methane’s degradation products. We conclude that any assumption other than full degradation of methane to CO2 in a rather short time frame is questionable, whereby the default CO2 yield from this oxidation, as far as GHG metrics are concerned, should be 100%. We re-calculate values for the global warming potential (GWP) metric in accordance with our findings, resulting in an increase in GWP100 from 29.8 and 27.0 to 30.40 and 27.65 kg CO2-equivalents/kg fossil and biogenic methane, respectively. Although we only present the implications in terms GWP, our proposal is conceptually valid for other GHG metrics as well.

Evaluation of Pollution Linked to Open-Air Storage of Black Shale by the Company Frontier S.A in Sakania in the South-East of the DR. Congo

The black shale from the company “Frontier S.A” in Sakania is impregnated with sulphide minerals such as pyrite which is an iron sulphide (FeS2) and chalcopyrite which is a double sulphide of copper and iron (Cu FeS2). Due to its storage in the open air, these sulphides are particularly oxidized. In addition, this black shale presents a certain physical and chemical instability which can be the basis of the degradation of the nearby surrounding environments (watercourses, soils, groundwater, etc.). It results from our chemical characterization tests that this black shale contains 0.05% Cu, 0.007% Co, 1.3% Fe, 0.007% Ni, 0.001% As; 0.0012% Pb; 0.0021 Cd; 1.75% of S.The mineralogical analysis reveals that the sample contains the main minerals: sulphides, in the form of chalcopyrite and pyrite; oxidized, in the form of quartz; carbonates, in the form of dolomite and calcite, and graphitic material (C). For the determination of the character of acid mine drainage, the static tests for predicting the AMD on the one hand, gave values for the net neutralization potential (NNP) and the ratio between the neutralization and acidification potentials (RPN). respectively 37.5 and 41.39, that is to say values classifying the black shale of Frontier as not generating ADM. And on the other hand, during the kinetic tests using the principle of testing periodic leaching of the sample over a long period, the percolates obtained made it possible to monitor the pH (between 6.2 to 7.07), the redox potential (between -39.8 to 92mV), the electrical conductivity (between 640 to 672μS/Cm), as well as the concentration rate of metals (low mobilization). This made it possible to conclude that the AMD did not exist on the site.

Prebiotic activity of enzymatically modified pea peel dietary fiber: An in vitro study

The study examined the prebiotic index of enzymatically modified insoluble dietary fiber from pea peel by using three probiotic bacterias; Lactobacillus rhamnosus ATCC 7469, Lactobacillus sakei ATCC 15521, Lactobacillus plantarum ATCC 8014 and one pathogenic bacteria; Escherichia coli ATCC 4157. A positive value for prebiotic potential was determined which was greater than inulin, unmodified dietary fiber, and standard glucose. The 30 h of cultivation, the cell density obtained from Lactobacillus rhamnosus ATCC 7469 culture conducted in MRS was 7.45 ± 0.08 log CFU/mL in glucose medium and 7.37 ± 0.07 log CFU/mL in dietary fiber medium. Growth kinetics analysis showed a positive effect for Lactobacillus spp. in DF medium. DF could boost cell biomass and relative growth rate of probiotic bacteria. Thus, the microbiome of the colon facilitates dietary fiber fermentation by bacteria shown in in vitro simulated gastrointestinal model.

On the mechanism and energetics of electrochemical alloy formation between mercury and platinum for mercury removal from aqueous solutions

Mercury pollution is an acute global concern threatening the health of humans and wildlife. Thus, there is a need for new and improved techniques to reduce emissions and remove toxic mercury from aqueous environments. Electrochemical alloy formation, specifically between mercury ions in aqueous solution and a platinum electrode, emerges as a promising solution. Through analysis of reaction mechanisms and energetics related to the formation and dissolution of the PtHg4 alloy, this study aims to deepen our understanding of the underlying processes of effective electrochemical mercury removal. Potentiodynamic measurements indicate rapid alloy formation at a clean platinum surface, proceeding with only trace amounts of metallic mercury on the surface. However, once the electrode surface has sufficient mercury coverage with an alloy thickness of around 1.5 nm, clear evidence of metallic mercury on the surface is observed. Furthermore, the amount of absorbed mercury on the cathode increases linearly in time. The onset potential for the alloy formation is experimentally determined using electrochemical quartz crystal microbalance with dissipation monitoring to be approximately 0.64 V vs. SHE, and the alloy dissolution (oxidation) onset potential is found to be approximately 0.98 V vs. SHE, at a mercury ion concentration of 10 mg/L. Density functional theory calculations are used to provide a theoretical value for the reversible potential from a thermodynamics perspective, yielding a value of 0.78 V vs. SHE at a mercury ion concentration of 10 mg/L. This value is in excellent agreement with the experimental results, suggesting an overpotential of about 0.14 and 0.20 V for the alloy formation and oxidation, respectively. These findings provide important information on the reaction mechanisms and overpotentials of the PtHg4 alloy formation and dissolution, which are key factors for development of large-scale mercury removal based on this technique, as well as fundamental understanding of the electrochemical alloy formation between mercury ions and platinum.

Anti-aging effect of mustard and flax seed oils based nanoemulsion gel on aged rat skin through antioxidant and anti-inflammatory activity

Skin aging is a common issue that is linked to changes in skin physiology, hydration, and barrier function. Dietary fatty acids (FA), particularly poly-unsaturated fatty acids (PUFA), can influence skin characteristics. It is reported that a deficiency of fatty acids in the skin is associated with skin aging. Therefore, the goal of the current study is to evaluate the antiaging effect of flaxseed oil or mustard oil-based nanoemulsion gel rich in fatty acids such as omega 3 on D-galactose-induced skin aging. N-hexane was used to extract the oils of black mustard and flax seed from their seeds, and the oils' fatty acid composition was then determined. A full factorial design was created to assess the impact of three variables: oil type, oil concentration, and S:Cos ratio, on various responses: globule size, zeta potential, and emulsification time of the self-nanoemulsifying system. Additionally, the polydispersity index, transmittance percentage, refractive index, cloud point, and viscosity were also estimated. TEM of the optimized formulations revealed a spherical form of oil globules with nanosize. The values for the zeta potential ranged from -12 to -34.2 mV. The optimized formulations were incorporated into a hydroxypropyl methyl cellulose solution to form a nanoemulsion gel. Skin aging was induced using the D-galactose model, and the impact of topical skin application of the optimized formulation gels on different biomarkers such as amino acids, B5, oxidative stress markers, inflammatory mediators and histopathological examination was evaluated. The results showed a considerable improvement in the evaluated parameters of the treated groups when compared to the untreated D-galactose group. The findings suggest that the nanoemulsifying system utilizing high doses of fixed plant oils could serve as a promising vehicle for enhancing skin rejuvenation. Flaxseed oil formulation showed greater potential compared to mustard oil formulation as skin antiaging.

Mismatch Negativity and P300 in the Diagnosis and Prognostic Assessment of Coma and Other Disorders of Consciousness.

The objective of this study was to investigate the value of mismatch negativity (MMN) and P300 event-related potentials for discriminating the consciousness state and predicting improvement of consciousness at 6months in patients with coma and other disorders of consciousness (DOC). We performed MMN and P300 on 42 patients with DOC with a mean onset time of 40.21 ± 19.43days. These patients with DOC were categorized into coma, unresponsive wakefulness syndrome (UWS), minimal consciousness minus (MCS-), and minimal consciousness plus (MCS +) groups according to neurobehavioral assessment and the Coma Recovery Scale-Revised score. The primary outcome was the improvement of consciousness at 6months in patients with DOC. We assessed the efficacy of MMN and P300 in quantitatively predicting the prognosis at 6months and the capability of MMN and P300 parameters to differentiate between DOC. At least one significant difference in either MMN or P300 parameters was displayed among the DOC groups, but not between the MCS- and MCS+ groups (significance level: 0.05). Both MMN and P300 amplitudes showed desirable predictive accuracy at 6months, with areas under the curve (AUCs) of 0.859 and 0.856, respectively. The optimal thresholds for MMN and P300 amplitudes were 2.044 and 1.095μV. However, the combined MMN-P300 amplitude showed better 6-month predictive accuracy (AUC 0.934, 95% confidence interval 0.860-1.000), with a sensitivity of 85% and a specificity of 90.9%. MMN and P300 may help discriminate among coma, UWS, and MCS, but not between patients with MCS- and patients with MCS+ . The MMN amplitude, P300 amplitude, and especially combined MMN-P300 amplitude at 6months may be interesting predictors of consciousness improvement at 6months in patients with DOC. Chinese Clinical Trial Registry identifier ChiCTR2400083798.

Biosynthesis of Silver and Gold Nanoparticles Using Geum urbanum L. Rhizome Extracts and Their Biological Efficiency

AbstractThe present study evaluates the biosynthesis of AgNPs and AuNPs using aqueous and ethanolic Geum urbanum L. rhizome extracts. The biosynthesized metal nanoparticles (MNPs) were characterized using UV-Vis spectroscopy, FTIR, DLS, SEM, EDX, and TEM. The UV-Vis spectra confirmed the synthesis of AgNPs and AuNPs through peaks corresponding to the surface plasmon effect of metallic Ag (400–430 nm) and Au (530–570 nm). FTIR analysis indicated that alcohols, phenols, proteins, and carbohydrates from G. urbanum rhizome extracts composition are involved in MNPs synthesis. In DLS analysis, AgNPs (34.26–41.14 nm) showed smaller hydrodynamic diameters than AuNPs (46.26–70.29 nm). At the same time, all values for zeta potential were negative, between − 21 and − 13 mV, suggesting good stabilities for all the colloidal MNPs systems in dispersion. TEM analysis showed that the biosynthesized AgNPs had a spherical morphology, while AuNPs were quasi-spherical, polygonal, and triangular. According to TEM data, AgNPs synthesized using aqueous and ethanolic G. urbanum rhizome extracts were characterized by mean diameters of 9.82 ± 3.68 and 14.29 ± 3.46 nm, while AuNPs by 15.88 ± 6.28 and 24.89 ± 10.75 nm, respectively. EDX analysis confirmed the presence of metallic Ag and Au in the MNPs composition by detecting strong signals at 3 (AgNPs) and 2.2 keW (AuNPs). In disc diffusion assay, MNPs showed good antimicrobial activity against Gram-positive (S. aureus MSSA, S. aureus MRSA, S. epidermidis) and Gram-negative (E. coli, P. aeruginosa, K. pneumoniae) bacteria and yeasts (C. albicans). AgNPs and AuNPs were also characterized by a significant antioxidant potential, evaluated through in vitro assays (lipoxygenase inhibition, DPPH radical scavenging activity, metal ion chelating activity, and hydroxyl radical scavenging assays). An overall better activity was obtained for the ethanolic G. urbanum rhizome extract and its derived AgNPs (EC50 = 34.2 ± 1.86 mg/mL in lipoxygenase inhibition assay). Therefore, the G. urbanum rhizome extracts proved to be excellent sources for biologically active AgNPs and AuNPs.

Focused reservoir characterization: analysis of selected sand units using well log and 3-D seismic data in 'Kukih' field, Onshore Niger Delta, Nigeria

This study focuses on the comprehensive reservoir characterization of the ‘Kukih’ Field within the onshore northeastern Niger Delta region, Nigeria. The absence of its detailed description with delineated reservoir properties, lateral continuity, and their use to identify potential reservoir quality and heterogeneity necessitated this study. Integrating well log and 3D seismic data, the investigation aims to elucidate reservoir properties, lithofacies, and depositional environments to unravel hydrocarbon potential. The geological setting, encompassing the Agbada Formation of Early and Middle Miocene age, is scrutinized through detailed geologic analysis. Petrophysical evaluation of four well logs (Kukih-1, Kukih-2, Kukih-3, and Kukih-4) facilitated the determination of key parameters such as shale volume, effective porosity, and water saturation. Seismic interpretation further enriched the structural characterization of the field. Results showcase three predominant reservoir sands (A, B, and C) with distinct lithofacies and thickness variations. Effective porosity ranges from Fair to Excellent, with permeability exhibiting high values for hydrocarbon reservoir potential. Water saturation trends, lithofacies distributions, and structural features were illuminated through iso-parametric maps and seismic analyses. Depositional environments were inferred through facies analysis, revealing the presence of funnel-, cylinder-, and bell-shaped successions that hint at intricate marine sedimentary processes. Challenges owing to limited core data were acknowledged, and the integration of methodologies emerged as a pivotal strategy for enhanced reservoir understanding. This study underscores the ‘Kukih’ Field's hydrocarbon potential, accentuating the significance of multidisciplinary approaches in deciphering complex reservoir systems. In light of the petrophysical analysis derived from the well logs and the identification of structural highs through the structural maps, this study recommends the drilling of unexplored zones exhibiting promising structural characteristics.

Correlations between intravascular pressure gradients and cerebral blood flow in patients with symptomatic, medically refractory, anterior circulation artery stenosis: an exploratory study

BackgroundFractional flow reserve is widely used in coronary disease management, with a threshold of 0.80. However, similar thresholds are unclear in functional assessment of intracranial atherosclerotic stenosis (ICAS).ObjectiveTo investigate the...

التخليق الحيوي لجسيمات الفضة النانوية باستخدام مستخلصات الشاي الأخضر

اصبح تركيب جسيمات الفضة النانوية بالطرق الخضراء بواسطة النباتات شائعًا بشكل متزايد بسبب ملاءمته للبيئة ، وتوفره ، وفعاليته وكلفته القليلة ، ويمكن التعامل معه بأمان ويمتلك تنوعًا واسعًا من المركبات الفعالة ، مثل مضادات الأكسدة و ومركبات مضادة للميكروبات. في الدراسة الحالية ، تم تصنيع جسيمات الفضة النانوية AgNPs باستخدام المستخلصات المائية والميثانولية لأوراق الشاي الاخضر التي اختزلت نترات الفضة, والتي تم توصيفها باستخدام العديد من التقنيات التحليلية مثل القياس الطيفي المرئي فوق البنفسجي (UV-Vis) ، والتحويل الطيفي بالأشعة تحت الحمراء (FTIR) ، والفحص المجهري الذري (AFM) ، وتشتت الأشعة السينية (XRD) وفحص جهد زيتا. أشارت الملاحظة البصرية إلى أن لون نترات الفضة المائية قد تحول بعد المعاملة بمستخلصات الأوراق وتأكد ذلك بواسطة أطياف UV-Vis. فضلا عن ذلك ، أظهر تحليل AFM أن الجسيمات كانت كروية الشكل ، مفردة أو في مجاميع بمتوسط ​​أحجام 108.3 و 84.76 نانومتر للمستخلصات المائية والميثانولية على التوالي. كذلك, أكدت تقنية XRD الطبيعة البلورية للجسيمات النانوية, وتم تقدير متوسط ​​الحجم وفقًا لمعادلة شيرير اذ بلغت 61.24 و 99.66 نانومتر للمستخلصات المائية والميثانولية (CANPs) على التوالي. بالإضافة إلى قيم زيتا المحتملة كانت-30.31 و -32.33 مللي فولت للمستخلصات المائية والميثانولية CANPs على التوالي.

Mott–Schottky Analysis of Historical and Archaeological Copper–based Objects

AbstractThe application of Mott–Schottky (M−S) analysis of impedance data to sub–micro samples extracted from the corrosion patina of copper, bronze, and brass archaeological artifacts attached to graphite electrodes is described. The corresponding theoretical approach is developed to account for the contribution of the composition and structure of the corrosion patina and the effect of the bare graphite substrate. Experimental data in contact with 0.10 M Na2SO4 aqueous solution at pH 6.28 are consistent with the p‐type semiconducting nature of the main copper corrosion products, cuprite, and tenorite. The values of the apparent flat band potential and the slope of the M−S plots allow archaeological samples to be grouped according to their M−S parameters (slopes and intercepts). Assuming equivalent conditions of corrosion, the resulting grouping is judged to be dependent on the composition, and/or method of manufacture, and/or age. Studied samples include Renaissance statues from the Hofkirche in Innsbruck and a variety of objects from museums and Archaeological Heritage Office (soprintendenza) in Austria (Bad Aussee, Johanneum Graz, and the Tyrolean State Museums), and Italy (Genoa and San Remo), dating from the Bronze Age to the 18th century. Complementary data are provided by voltammetry of immobilized particles.

Effects of low-frequency magnetic field on solubility, structural and functional properties of soy 11S globulin.

Soy 11S globulin has high thermal stability, limiting its application in the production of low-temperature gel foods. In this study, the low-frequency magnetic field (LF-MF, 5 mT) treatment (time, 30, 60, 90, and 120 min) was used to improve the solubility, conformation, physicochemical properties, surface characteristics, and gel properties of soy 11S globulin. Compared with the native soy 11S globulin, the sulfhydryl content, emulsifying capacity, gel strength, water-holding capacity, and absolute zeta potential values significantly increased (P < 0.05) after LF-MF treatment. The LF-MF treatment induced the unfolding of the protein structure and the fracture of disulfide bonds. The variations in solubility, foaming properties, viscosity, surface hydrophobicity, and rheological properties were closely related to the conformational changes of soy 11S globulin, with the optimum LF-MF modification time being 90 min. LF-MF treatment is an effective method to improve various functional properties of native soy 11S globulin, and this study provides a reference for the development of plant-based proteins in the food industry. © 2024 Society of Chemical Industry.

A study the 16 O + 166 E R , 16 O + 197 Au Systems Using Calculations of Quasi-elastic Scattering

Specific systematic studies on the nuclear potential parameter for the heavy-ion reactions which includes the systems have been achieved by using large-angle quasi elastic scattering at deep sub-barrier energies close to the Coulomb barrier height. The elastic scattering barrier distribution Dqelas a function of energy has also been calculated in this theoretical study. The single-channel (SC) and coupled-channels calculations have been carried out to elicit the nuclear potential. The chi-square method X2 has been used find the best value of the nuclear potential in comparison with the experimental data. The best values of the nuclear potential were found from the calculations of the single channels for systems: 16O+166ER , 16O+197Au, which are equal to (60.5, 100) MeV, respectively.

Reference values for nerve conduction studies of the peroneal, tibial, and sural nerve derived from a large population-based cohort: Associations with demographic and anthropometric characteristics-The Maastricht study.

Nerve conduction studies (NCSs) are widely used to support the clinical diagnosis of neuromuscular disorders. The aims of this study were to obtain reference values for peroneal, tibial, and sural NCSs and to examine the associations with demographic and anthropometric factors. In 5099 participants (aged 40-79 years) without type 2 diabetes of The Maastricht Study, NCSs of peroneal, tibial, and sural nerves were performed. Values for compound muscle action potential (CMAP) and sensory nerve action potential amplitude, nerve conduction velocity (NCV), and distal latency were acquired. The association of age, sex, body mass index (BMI), and height with NCS values was determined using uni- and multivariate linear regression analyses. Detailed reference values are reported per decade for men and women. Significantly lower NCVs and longer distal latencies were observed in all nerves in older and taller individuals as well as in men. In these groups, amplitudes of the tibial and sural nerves were significantly lower, whereas a lower peroneal nerve CMAP was only significantly associated with age. BMI showed a multidirectional association. After correction for anthropometric factors in the multivariate analysis, the association between sex and NCS values was less straightforward. These values from a population-based dataset could be used as a reference for generating normative values. Our findings show the association of NCS values with anthropometric factors. In clinical practice, these factors can be considered when interpreting NCS values.

Evaluation of the antifungal properties of nanoliposomes containing rhinacanthin-C isolated from the leaves of Rhinacanthus nasutus.

Fungal infections represent a challenging threat tothe human health. Microsporum gypseum and Trichophyton rubrum are pathogenic fungi causing various topical mycoses in humans. The globally emerging issue of resistance to fungi demands the development of novel therapeutic strategies. In this context, the application of nanoliposomes as vehicles for carrying active therapeutic agents can be a suitable alternative. In this study, rhinacanthin-C was isolated from Rhinacanthus naustus and encapsulated in nano-liposomal formulations, which were prepared by the modified ethanol injection method. The two best formulations composed of soybean phosphatidylcholine (SPC), cholesterol (CHL), and tween 80 (T80) in a molar ratio of 1:1:0 (F1) and 1:1:0.5 (F2) were proceeded for experimentation. The physical characteristics and antifungal activities were performed and compared with solutions of rhinacanthin-C. The rhinacanthin-C encapsulating efficiencies in F1 and F2 were 94.69 ± 1.20% and 84.94 ± 1.32%, respectively. The particle sizes were found to be about 221.4 ± 13.76 nm (F1) and 115.8 ± 23.33 nm (F2), and zeta potential values of -38.16 mV (F1) and -40.98 mV (F2). Similarly, the stability studies of rhinacanthin-C in liposomes demonstrated that rhinacanthin-C in both formulations was more stable in mediums with pH of 4.0 and 6.6 than pure rhinacanthin-C when stored at the same conditions. Rhinacanthin-C in F1 was slightly more stable than F2 when stored in mediums with a pH of 10.0 after three months of storage. However, rhinacanthin-C in both formulations was less stable than pure rhinacanthin-C in a basic medium of pH 10.0. The antifungal potential was evaluated against M. gypsum and T. rubrum. The findings revealed a comparatively higher zone of inhibition for F1. In the MIC study, SPC: CHL: T80 showed higher inhibition against M. gypseum and a slightly higher inhibition against T. rubrum compared to free rhinacanthin-C solution. Moreover, rhinacanthin-C showed significant interaction against 14α-demethylase in in silico study. Overall, this study demonstrates that nanoliposomes containing rhinacanthin-C can improve the stability and antifungal potential of rhinacanthin-C with sustained and prolonged duration of action and could be a promising vehicle for delivery of active ingredients for targeting various fungal infections.

Performance simulation of the perovskite solar cells with Ti3C2 MXene in the SnO2 electron transport layer

MXenes, a class of two-dimensional (2D) transition metal carbides and nitrides, have a wide range of potential applications due to their unique electronic, optical, plasmonic, and other properties. SnO2–Ti3C2 MXene with different contents of Ti3C2 (0.5, 1.0, 2.0, 2.5 wt‰), experimentally, has been used as electron transport layers (ETLs) in Perovskite Solar Cells (PSCs). The SCAPS-1D simulation software could simulate a perovskite solar cell comprised of CH3NH3PbI3 absorber and SnO2 (or SnO2–Ti3C2) ETL. The simulation results like Power Conversion Efficiency (PCE), Open circuit voltage (VOC), Short circuit current density (JSC), Fill Factor (FF), and External Quantum Efficiency (EQE) have been compared within samples with different weight percentages of Ti3C2 MXene incorporated in ETL. Reportedly, the ETL of SnO2 with Ti3C2 (1.0 wt‰) effectively increases PCE from 17.32 to 18.32%. We simulate the role of MXene in changing the ideality factor (nid), photocurrent (JPh), built-in potential (Vbi), and recombination resistance (Rrec). The study of interface recombination currents and electric field shows that cells with 1.0 wt‰ of MXene in SnO2 ETL have higher values of ideality factor, built-in potential, and recombination resistance. The correlation between these values and cell performance allows one to conclude the best cell performance for the sample with 1.0 wt‰ of MXene in SnO2 ETL. With an optimization procedure for this cell, an efficiency of 27.81% is reachable.

Diffusiophoretic Behavior of Polyelectrolyte-Coated Particles.

Diffusiophoresis, the movement of particles under a solute concentration gradient, has practical implications in a number of applications, such as particle sorting, focusing, and sensing. For diffusiophoresis in an electrolyte solution, the particle velocity is described by the electrolyte relative concentration gradient and the diffusiophoretic mobility of the particle. The electrolyte concentration, which typically varies throughout the system in space and time, can also influence the zeta potential of particles in space and time. This variation affects the diffusiophoretic behavior, especially when the zeta potential is highly dependent on the electrolyte concentration. In this work, we show that adsorbing a single bilayer (or 4 bilayers) of a polyelectrolyte pair (PDADMAC/PSS) on the surface of microparticles resulted in effectively constant zeta potential values with respect to salt concentration throughout the experimental range of salt concentrations. This allowed a constant potential model for diffusiophoretic transport to describe the experimental observations, which was not the case for uncoated particles in the same electrolyte system. This work highlights the use of simple polyelectrolyte pairs to tune the zeta potential and maintain constant values for precise control of diffusiophoretic transport.

MODIFYING FRACTION EXTRACTED FROM SESEWANUA (CLERODENDRUM FRAGRANS WILD) LEAVES IN SNEDDS PREPARATIONS: CHARACTERIZATION AND BIOAVAILABILITY TEST

Objective: This study aimed to determine the effect of compound modification using acyl chloride derivatives on n-hexane: ethyl acetate fraction of sesewanua leaves, focusing on the characteristics and pharmacokinetics profile in Self-Nano-emulsifying Drug Delivery System (SNEDDS) preparations. Methods: A quasi-experimental method was used with six SNEDDS formulas, namely F0 (without active substance), F1 (acetyl chloride fraction), F2 (propanoyl chloride fraction), F3 (butyryl chloride fraction), and F4 (pentanoyl chloride fraction) and F5 (piperine compound). The fractions were subjected to characterization tests, including particle size, polydispersity index, and zeta potential as well as determination of pharmacokinetics profile using the modified crane and Wilson method. Results: The results showed that the characterization tests of particle size using Particle Size Analyzer (PSA) for F0-F5 on gastric fluid included 15.8, 17,367, 20,367, 15.8, 28.233, and 21.533 nm. The polydispersity index values were 0.211, 0.438, 0.311, 0.383, 0.394, and 0.397, while the Zeta Potential values were-22,267,-22.2,-23.5,-24,033,-22,967, and-21.6 mV, respectively. The pharmacokinetics profile of AUC0-∞ was as follows: F0 0 μg, F1 492.83, F2 492.83, F3 245.98, F4 492.94, and F5 843.38 μg. Fraction five (F5) as a control had a higher AUC0-∞ value than compared to the fractions modified with acyl chloride derivatives. The T1/2 elimination values were F0 0 h, F1 22.5 h, F2 10.811 h, F3 35.54 h, F4 231.01 h, and F5 15.469 h. Conclusion: Based on the results, the addition of acetyl, propanoyl, butyryl, and penthanoyl chloride affected Particle Size Characterization Analysis and pharmacokinetics profile of SNEDDS preparation of n-hexane: ethyl acetate fraction. Structural modification showed the ability to alter the bioavailability of the active ingredient according to the desired therapeutic goal.

Waste Cooking Oil Biodiesel and Their Nanobiodiesel Blends Infused with Reduced Graphene Oxide (RGO) Nanoparticles for Diesel Engine Applications

This work focusses on the potential application of waste cooking oil (WCO) as alternative to diesel as it is abundantly, locally available. The oil is subsequently converted into its biodiesel called waste cooking biodiesel (WCOBD). GCMS studies of the waste cooking oil and its biodiesel is carried out to determine the fatty acid composition. Further WCOBD is blended with diesel to produce its WCOBD B20 blend. The physio-chemical properties of the WCO, WCOBD, WCOBD B20 and their nano-biodiesel blends were determined and were compared with diesel. These properties of WCOBD B20 are in good agreement with diesel. This B20 blend can successfully provide 20% substitute to fossil diesel and save foreign exchange besides providing energy security to India. The fuel properties of the WCOBD B20 blends are further modified by adding carbon derived nanoparticles of reduced graphene oxide (RGO) to prepare nano-biodiesel blends. The percentage of RGO nanoparticles were varied from 20% to 100 % by volume insteps of 20% using suitable SDS surfactants. The stability of these nano-biodiesel blends is determined by using zeta potential method. The stability of decreased with increase in the nano-particle dosage in base biodiesel blends. Accordingly, the blends with dosage beyond 80% showed lower stability in terms of lower zeta potential values. The nano-biodiesel blends showed improvement in calorific value and self-ignition temperature compared to the B20 biodiesel blend. Among the Nano-biodiesel blends considered WCOME B20 RGO80 showed comparatively higher BTE (11.67%), reduced emissions of smoke opacity (14.63%), HC (21.42%), CO (16.67%), ID (10%), CD (16.67%) and increased NOx (2.5%), and PP (15.38%) respectively when compared to the WCOBD B20 blend.

Flash drought monitoring using diurnal-provided evaporative demand drought index

Flash drought, as a relatively new concept, represents a rapidly evolving drought with sudden onset, short-term duration, and great destructiveness. With the warming of the planet in recent decades, the frequent occurrences of flash droughts have resulted in considerable losses to personnel and properties on a global scale. Nowadays, the emerging Evaporative Demand Drought Index (EDDI) has revealed its significant potential and adaptability in the early warning and quantification of flash droughts. In this study, an advanced method for improving the accuracy and temporal resolution of EDDI is proposed. The new set of EDDI estimates is calculated using diurnal-provided potential evapotranspiration values that have been calibrated with weather parameters and Global Navigation Satellite Systems (GNSS) atmospheric products. Then, the monitoring performances of flash droughts resulting from the diurnal-provided EDDIs are evaluated over the period 2010–2021 in Hong Kong. Results showed that the Probability Of Detection (POD) and False Alarm Rate (FAR) were 87.1 % and 16.7 %, respectively. By comparing with their counterparts obtained from the use of monthly EDDIs, it was found that the improvements made by the new method in the metrics of POD and FAR were 24.6 % and 11.2 %, respectively. In addition, with the use of diurnal-provided EDDI, the mean lead time for flash drought detection has been prolonged to 37.74 days, offering more time to prevent and mitigate the detrimental effects brought by flash drought events.