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Transesterification tend to be the most adopted method of producing biodiesel, but the outcome is associated with high viscosity especially at low temperature. Viscosity is the most important rheological property of biodiesel. This paper investigates the impact of Cupper II Carbonate (CuCO3) nanoparticles on the rheology of biodiesel extracted from castor oil. The CuCO3 nanoparticles has been subjected to Xray fluoroscopy (XRF) in order to determine its elemental composition. The crude castor oil was purified, trans-esterified and CuCO3 nanoparticles were dispersed in the trans-esterified oil with concentration ranging from 0.1wt% to 1.0wt% in 0.1wt% interval. Fourier Transform Infrared spectra (FTIR) was used to examine the functional groups of the transesterified sample. The samples were subjected to viscosity measurement using digital viscometer at a temperature range of 200C to 1000C at the interval of 200C. The XRF characterization shows that the CuCO3 nanoparticles used is pure due to the fact that its percentage concentration tends to be 92.11%. FTIR analysis indicate that the ester (biodiesel) was achieved at 1744.4 peak. The viscosities of the samples decrease as the temperature increases and with the increase in the amount CuCO3 concentration. The viscosity tends to be best at the application of 0.3wt%. This shows that CuCO3 nanoparticles can be used as biodiesel additive using castor oil as feedstock. [ABSTRACT FROM AUTHOR]

Background: Medicated oils and Clarified butter are often utilized in the Traditional System of Indian Medicine for internal and external use. To improve the durability and efficacy of therapeutic oil unique processing is advocated known as Murchhana. Specific ingredients are mentioned for each oil. The current work seeks to conduct a comparative analytical evaluation of processed and unprocessed castor oil. Materials and Methods: Both the oils were analyzed for rancidity, specific gravity at 25°C, refractive index, iodine value, saponification value, acid value, peroxide value, free fatty acids, and HPTLC. Results: There was a significant difference between unprocessed and processed castor oil. Physicochemical and HPTLC analysis revealed significant differences in all samples, indicating that extra active chemicals were obtained in the processed oil. Saponification Value was increased in processed oil, however, iodine value, and acid value were found to decrease indicating the enhancement of the shelf life. Thus, utilizing adopting processing techniques the shelf life of the oil can be improved. Conclusion: Based on the results of analytical criteria, it implies the significance of processing the castor oil as mentioned in the Ayurvedic texts. [ABSTRACT FROM AUTHOR]

Lipid oxidation is a spontaneous process in fats and, consequently, in products with significant fat content. Many cosmetics fall into this category, presenting an intrinsic relationship between the productʼs quality, oxidation capacity, and market value. This study comprehensively investigated the aging of body lotions, accentuating the role of their chemical formulations. Sensory analysis clarified that controlled temperature-induced aging significantly altered the lotions' appearance, texture, color, and, to a lesser extent, odor, hinting at the onset of rancidity. As lipid peroxidation unfolds, the emergence of secondary oxidation products like aldehydes, ketones, and alcohols becomes prominent. These secondary products indicate a potential degradation in the lotion's quality and efficacy. Quantifying the primary oxidation products was possible using methods like the quantification of Conjugated Dienes (CD) expressed in percentage and the Peroxide Index (PI) method expressed in meqO 2 /kg of a dry sample. On the other hand, methods such as the p-Anidisine Index (pAi) and the thiobarbituric acid reactive substances (TBARS) with malonaldehyde (MDA) expressed as malonaldehyde concentration (mg/g of dry sample) provided the quantification of secondary oxidation products. Regarding lipid oxidation, lotions containing sunflower and soybean oils emerged as notably susceptible. Conversely, samples that demonstrated minimal oxidation, were attributed to protective elements such as Aloe barbadensis and Calendula officinalis extracts. Examining into secondary oxidation, four samples displayed the highest TOTOX values, indicating extensive oxidation. A discernible correlation was observed between TOTOX values and natural extracts' presence (or lack), underscoring their protective or exacerbating roles. Certain natural ingredients, including A. barbadensis leaf juice powder and C. officinalis flower extract, were recognized as supporters against oxidation. Yet, components like PEG-40 hydrogenated castor oil can, paradoxically, seem to intensify the oxidative cascade. This research provides crucial insights into the interplay between natural extracts and lipid oxidation in body lotions. The elucidated results accentuate the necessity for judicious ingredient selection, balancing the inclusion of natural extracts to ensure product quality, longevity, and safety. [Display omitted] • Aloe barbadensis and Calendula officinalis extracts show protection against oxidation. • PEG-40 hydrogenated castor oil accelerates lipid oxidation acting as a pro-oxidant. • Accelerated aging tests show changes in lotion appearance, texture, color, and odor. • Sunflower and soybean oils exhibited heightened vulnerability to lipid oxidation. • A correlation between TOTOX values and antioxidant-rich natural extracts emerged. [ABSTRACT FROM AUTHOR]

To enhance the properties of SBS and crumb rubber-modified asphalts, four different amounts (5%, 10%, 15%, and 20%) of castor oil were added to crumb rubber-modified asphalts to mitigate the adverse effects of high levels of fine crumb rubber particles on the aging resistance of SBS and crumb rubber-modified asphalt. Initially, a conventional test was conducted to assess the preliminary effects of bio-oil on the high-temperature and anti-aging properties of SBS and crumb rubber-modified asphalt. Subsequently, dynamic shear rheometer and bending beam rheometer tests were employed to evaluate the impact of bio-oil on the high- and low-temperature and anti-fatigue properties of SBS and crumb rubber-modified asphalt. Finally, fluorescence microscopy and Fourier transform infrared spectroscopy were used to examine the micro-dispersion state of the modifier and functional groups in bio-oil, SBS and crumb rubber composite-modified asphalts. The experimental results indicated that bio-oil increased the penetration of SBS and crumb rubber-modified asphalt, decreased the softening point and viscosity, and significantly improved its aging resistance. The addition of bio-oil enhanced the anti-fatigue properties of SBS and crumb rubber-modified asphalt. The optimal amount of added bio-oil was identified. Bio-oil also positively influenced the low-temperature properties of SBS and crumb rubber-modified asphalt. Although the addition of bio-oil had some adverse effects on the asphalt's high-temperature properties, the asphalt mixture modified with bio-oil, SBS, and crumb rubber still exhibited superior high-temperature properties compared to unmodified asphalt. Furthermore, fluorescence microscopy and Fourier transform infrared spectroscopy results demonstrated that bio-oil can be uniformly dispersed in asphalt, forming a more uniform cross-linked structure and thereby enhancing the aging resistance of SBS and crumb rubber-modified asphalt. The modification process involved the physical blending of bio-oil, SBS, and crumb rubber within the asphalt. Comprehensive research confirmed that the addition of bio-oil has a significant and positive role in enhancing the properties of SBS and crumb rubber-modified asphalt with different composite crumb rubber particle size ratios. [ABSTRACT FROM AUTHOR]

Ethoxylation is one of the common industrial process in which ethylene oxide (EO) is added to compounds containing active hydrogen atom (OH, COOH, SH, NH, etc.) to form surfactants. Alcohol ethoxylates are a major class of non‐ionic surfactants composed of an alkyl chain combined with few EO units. They are widely used in homecare products, personal care products, textiles, oilfield, construction, lubricants, food, paper, leather. The analysis of these ethoxylates possess several challenges since they contain 'n' number of EO units (n > 1). With increase in "n," the product becomes more and more viscous and the boiling point increases making it difficult to analyze by normal gas chromatography (GC) technique. This paper describes a method of derivatizing these ethoxylates so that they can be eluted on a high temperature GC. BSTFA (N, O‐bis (trimethylsilyl) trifluoroacetamide) is used as the derivatizing agent (silylating agent). The ethoxylate combines with BSTFA to form the corresponding trimethylsilylated (TMS) product, which have comparatively lower boiling point. Thus, we detect trimethyl silyl product, which is the resemblance for the ethoxylated product. In this paper, we present a quantitative GC method for the ethoxylates of a few simple alcohols (2‐ethyl hexanol, glycerin), and complex vegetable oils (castor oil). The products formed during the reaction have also been identified on a gas chromatograph coupled with mass spectrometer (GCMS). GCMS shows the mass corresponding to the TMS derivatized product. The derivatization technique not only helps in increasing the volatility of these compounds but also improves the chromatographic efficiency, selectivity, and enhances the detectability. [ABSTRACT FROM AUTHOR]

The popularity of royal jelly (RJ) as a functional food has attracted attention from various industries, especially nutraceuticals, due to the increasing demand from health enthusiasts. Sebacic acid, 10‐hydroxy decanoic acid, and trans‐10‐hydroxy‐2‐decanoic acid are the primary medium‐chain fatty acids (MCFAs) within RJ responsible for their health benefits. This review aims to consolidate information on these MCFAs' metabolic relationship and health functionalities in nutraceutical applications. We also investigated the natural characteristics mediated by these MCFAs and their metabolism in organisms. Finally, the production of these MCFAs using conventional (from castor oil) and alternative (from RJ) pathways was also discussed. This review can be a reference for using them as functional ingredients in nutraceutical industries. [ABSTRACT FROM AUTHOR]

The production, optimisation, physicochemical, and electroanalytical characterisation of a low-cost electrically conductive additive manufacturing filament made with recycled poly(lactic acid) (rPLA), castor oil, carbon black, and graphite (CB-G/PLA) is reported. Through optimising the carbon black and graphite loading, the best ratio for conductivity, low material cost, and printability was found to be 60% carbon black to 40% graphite. The maximum composition within the rPLA with 10 wt% castor oil was found to be an overall nanocarbon loading of 35 wt% which produced a price of less than £0.01 per electrode whilst still offering excellent low-temperature flexibility and reproducible printing. The additive manufactured electrodes produced from this filament offered excellent electrochemical performance, with a heterogeneous electron (charge) transfer rate constant, k0 calculated to be (2.6 ± 0.1) × 10−3 cm s−1 compared to (0.46 ± 0.03) × 10−3 cm s−1 for the commercial PLA benchmark. The additive manufactured electrodes were applied to the determination of β-estradiol, achieving a sensitivity of 400 nA µM−1, a limit of quantification of 70 nM, and a limit of detection of 21 nM, which compared excellently to other reports in the literature. The system was then applied to the detection of ß-estradiol within four real water samples, including tap, bottled, river, and lake water, where recoveries between 95 and 109% were obtained. Due to the ability to create high-performance filament at a low material cost (£0.06 per gram) and through the use of more sustainable materials such as recycled polymers, bio-based plasticisers, and naturally occurring graphite, additive manufacturing will have a permanent place within the electroanalysis arsenal in the future. [ABSTRACT FROM AUTHOR]

The recovery of valuable metals from copper slag (CS) is an effective way to realize its resource utilization. However, the use of fossil reductants in the reduction process can result in large amounts of carbon dioxide emissions. Therefore, a low-carbon method for recovering valuable metals from CS using castor oil as a green reductant is proposed in this study. The reduction behavior of CS is investigated through thermodynamic calculations, reduction experiments and thermogravimetric analysis. Under optimal experimental conditions, the recovery ratios of Fe and Cu reach 98.75% and 99.24%. The formed crude concentrate contains 94.27 wt.% Fe, 0.82 wt.% Cu and 0.042 wt.% S, which can partially replace the raw material in the production of weathering steel. Meanwhile, the waste residue produced can be used as the base material for glass-ceramics. The reduction characteristics of castor oil, CS and CaO blends are investigated based on thermogravimetric analysis, and the entire reduction process is divided into five stages. The activation energy of the reduction process is calculated using two iso-conversion methods, KAS and FWO. The reaction models for two reduction stages (stage IV and stage V) are determined using the Coats-Redfern method. The reaction model changes significantly with increasing temperature, shifting from a limiting surface reaction (R2) to a chemical reaction (C3). This study provides new insights into the resource utilization of CS and the development of low-carbon metallurgical technology. [ABSTRACT FROM AUTHOR]

In the quest for sustainable lubrication solutions, the present research explored the potential of five organic compounds as additives in castor oil (CO) to improve its lubricating properties. The compounds tested were curcumin, eugenol, 1,3-Diphenyl-2-propanone, 1,3-Diphenyl-2-propenone, and 1,3-Diphenyl-1,3-propanedione. The main results showed that each additive enhanced at least one characteristic of CO. Most of the additives lowered the density of the castor oil but increased the viscosity by up to 20%. Curcumin and eugenol were particularly effective in creating thicker lubricant films and higher film thickness ratios. Eugenol and 1,3-Diphenyl-2-propanone significantly reduced the friction coefficient by up to 25%. Wear rate and wear mechanisms were significantly reduced with all the additives, achieving a reduction in wear rate of up to 50% (CO+curcumin). All the additives, except the 1,3-Diphenyl-1,3-propanedione, enhanced the oxidation onset temperature up to 8 °C. The influence of chemical structure was also addressed. The optimal additive combination for a specific application that demands minimal friction and wear, as well as strong oxidation stability, was eugenol, followed by curcumin and 1,3-Diphenyl-2-propanone. Overall, the research contributes to the development of eco-friendly lubricants, aligning with the growing demand for green industrial applications, and highlights the significant tribological benefits of these substances as sustainable additives in biolubricant formulations. [ABSTRACT FROM AUTHOR]

Objective: Preparation and characterization of nano-emulsion formulations for Asparagus densiflorus aerial and root parts extracts. Significance: Genus Asparagus is known for its antimicrobial and anticancer activities, however, freeze dried powder of aqueous – alcoholic extract prepared in this study, exhibited a limited water solubility, limiting its therapeutic application. Thus, encapsulation of its phytochemicals into nano-emulsion is proposed as a solution to improve water solubility, and facilitate its clinical translation. Methods: the composition of extracts for both aerial and root parts of Asparagus densiflorus was identified by HPLC and LC-MS analysis. Nano-emulsion was prepared via homogenization where a mixture of Castor oil: phosphate buffered saline (10 mM, pH 7.4): Tween 80: PEG 600 in a ratio of 10: 5: 2.5: 2.5, respectively. Nano-emulsion formulations were characterized for particle size, polydispersity index (PDI), zeta potential, TEM, viscosity and pH. Then, the antibacterial and anticancer activities of nano-emulsion formulations versus their pure plant counterparts was assessed. Results: The analysis of extracts identified several flavonoids, phenolics, and saponins which were reported to have antimicrobial and anticancer activities. Nano-emulsion formulations were monodispersed with droplet sizes ranging from 80.27 ± 2.05 to 111.16 ± 1.97 nm, and polydispersity index ≤0.3. Nano-emulsion formulations enhanced significantly the antibacterial (multidrug resistant bacteria causing skin and dental soft tissues infections) and anticancer (HuH7, HEPG2, H460 and HCT116) activities compared to their pure plant extract counterparts. Conclusion: Employing a nano-delivery system as a carrier for phytochemicals might be an effective strategy to enhance their pharmacological activity, overcome their limitations, and ultimately increase their potential for clinical applications. [ABSTRACT FROM AUTHOR]

High‐barrier performance, especially under extreme working conditions, is the key to replacing other types of packaging materials with paper‐based materials. In this paper, two biomass‐based polymers, sodium alginate (SA), and chitosan, were used to form a barrier coating with silicone emulsions to prepare a high‐performance paper‐based barrier material. By double coating, the water and oilproof functions were superimposed. The two prepared coated papers were characterized by infrared spectroscopy analysis, contact angle test, and scanning electron microscopy analysis, while their water resistance, oil resistance, thermal oil resistance, and thermal stability were tested. The water and oil repellency were achieved by double coating. The Cobb value of the chitosan‐silicone emulsion‐coated paper reached 5.3 g/m2, with a Kit grade of Level 12, and could block the penetration of castor oil at 80°C within 24 h. The Cobb value of the sodium alginate‐silicone emulsion‐coated paper was 41.6 g/m2, much higher than that of the uncoated paper, with a Kit grade of up to Level 10, which could slow down the rate of castor oil penetration at 80°C within 24 h. The test results showed that there was no chemical reaction between the paper‐based coatings, and the coated paper surface had good film formation, while the double coating method increased the thermal decomposition temperature of the overall barrier coating, effectively improving the thermal stability of the coating and achieving high‐barrier performance at lower cost and under extreme working conditions. Highlights: Water and oil resistance under extreme operating conditions.High‐performance paper‐based barrier materials.Dual‐layer coating method for water and oil repellency.High‐barrier performance at lower cost.Excellent hot oil resistance and thermal stability. [ABSTRACT FROM AUTHOR]

Flax fibre-reinforced bio-composites are developed using both unmodified petroleum-based epoxy and Epoxy Methyl Ricinoleate (EMR) toughened epoxy modified with microcrystalline cellulose (MCC) as the base matrix. Base-catalyzed transesterification is employed for the synthesis of EMR as a low-viscosity reactive green monomer for the modification of petroleum-based epoxy. MCC is incorporated into the EMR-modified epoxy through mechanical stirring and subsequent sonication at loading rates of 1%, 3%, and 5% by weight. The compression molding technique was employed to prepare the composites. The results show an enhancement in tensile strength, modulus, impact strength, and inter-laminar shear strength values up to 19%, 34%, 34.2%, and 22.7%, respectively for MCC filled EMR toughened epoxy composite compared to neat epoxy composite. The storage and loss moduli, as revealed by the dynamic mechanical analysis (DMA), also demonstrate improvement for the 3% MCC-C composite signifying the improved fibre/matrix bonding. The low-velocity impact test at 10 J and 20 J for non-perforation and perforation conditions was also performed on the composites. The MCC-incorporated EMR-modified composite demonstrated the highest low velocity impact resistance among all other bio-composites, highlighting its potential for use in semi-structural applications due to the enhanced interfacial adhesion. The SEM analysis revealed that the fibre surface of MCC-modified EPEMR20 composites exhibited surface damage, and adherence of MCC fillers and matrix fragments, indicating superior adhesion to the matrix system. [ABSTRACT FROM AUTHOR]

In this work, the electrospinnability of cellulose acetate butyrate (CAb) solutions, and the ability of the resulting micro‐ and nano‐architectures to structure castor oil are studied aiming to develop eco‐friendly lubricating greases. Particles, beaded‐fibers, defect‐free fibers, and porous nanostructures are successfully prepared by dissolving CAb in N,N‐dimethylacetamide/acetone (DMAc:Ac, 1:2 w/w) and methylene chloride/acetone (DM:Ac, 1:1 w/w) solvent mixtures at different concentrations (2.5–15 wt.%). The formation of bead‐free nanofibers is favored at concentration above 10 wt.%, when solutions achieve relaxation times of ≈50 ms and shear‐thinning in extensional and shear flow tests, respectively. Non‐porous and porous CAb nanostructures are successfully used as castor oil thickeners at concentrations of 3–5 wt.%, leading a wide variety of rheological responses which mimic those of traditional semisolid lubricants. The surface properties of the nanofibers have a significant impact on the wear and friction performance in metal–metal contact, which has been associated with the oil release ability of the generated 3D network. Oleo‐dispersions prepared with smooth fibers show tribological performance comparable to, or even better than, commercial lithium greases. Overall, this study reveals the potential of CAb electrospun nanostructures for the development of next‐generation renewable semisolid lubricant formulations. [ABSTRACT FROM AUTHOR]

Introduction: The castor bean (Ricinus communis L.), is an oilseed of relevant economic and social importance. From its seeds is extracted an oil of excellent properties, having wide use as industrial input and several applications. It is cultivated since the times of the ancient civilizations, the castor bean is a rustic plant, resistant to drought, belonging to the family of Euphorbiaceae, Drought stress, in addition to the negative effect on yield, causes or exacerbates other stresses, especially the stress of nutrient deficiencies for the plant. The purpose of this investigation was to study the effect of irrigation levels and Superabsorbents and biofertilizers on the agronomic properties of castor oil. Materials and methods: This experiment was conducted in West Azarbaijan Agricultural Research and Education Center, Orumieh-Iran in 2018-2021 crop season. A field experiment was carried out by a split-plot design based on a completely randomized block design with three replications. The first factor included Four levels (70, 100, 130, and 160 mm of evaporation pan), in the main plot and Sub-factor includes application of biofertilizer combination in four levels (Azospirillium, Citrobacter, combination of application of Azospirillium in Citrobacter and control without fertilizer) and superabsorbent in two levels (superabsorbent consumption and non-superabsorbent consumption) as factorial were placed in subplots. In this study, Chlorophyll a, Chlorophyll b, Cartonoid, Soluble sugar, prolin content, Catalase, Malondialdehyde, and protein content were measured. Also Traits were analyzed by using SAS 9.2 software and means comparison was tested by least significant difference (LSD). Results and discussion: Based on the results of the combined analysis of the variance of the data, there was a significant difference in was observed between the two years in terms of malondialdehyde content. There was a significant difference between the irrigation levels in terms of the effect on all traits of the probability level of 1%. The interaction effect of year and irrigation was significant only on leaf proline content at the level of 1% probability. There was a significant difference between the biofertilizer treatments and the interaction effect of biofertilizer on irrigation and superabsorbent levels in terms of the effect on all traits at the level of one percent probability. The interaction effect of irrigation with superabsorbent on chlorophyll a and b content and soluble sugar content at 1% probability level and on proline content and protein percentage at 5% probability level was significant. Between treatments of biofertilizer with superadd interaction in terms of the effect on chlorophyll b content, soluble sugar, proline content, malondialdehyde content, and protein percentage at the level of 1% percent and in terms of the effect on chlorophyll content, carotenoids and catalase activity in 5% probability level There was a significant difference. The results showed the highest chlorophyll a (23.00 mg g-1) and b content (14.93 mg g-1) as well as carotenoids (30.39 mg g-1) and the lowest amount of soluble sugar (113.33 micromol g-1 fresh weight), catalase (32.97ΔA240 mg-1 protein), malondialdehyde (132.44 nmol g-1 FW) and protein percentage (4.69%) were assigned to with Citrobacter treatment and irrigation after 70 mm of evaporation. Also, the highest soluble sugar content (131.42 micromol g-1 FW), proline (65.91 micromol g-1 FW), protein (11.48 %) was assigned to the treatment with Azosprilium + Citrobacter and irrigation after 160 mm of evaporation. In this study, the use of superabsorbent in the irrigation treatment of 70 mm evaporation had the highest chlorophyll a (21.29 mg g-1) and b content (12.78 mg g-1) and the lowest amount of soluble sugar (112.50 micromol g-1 FW), proline (26.50 micromol g-1 FW), catalase (35.99 ΔA mg-1 protein) and protein percentage (5.00%), While the highest soluble sugars content (129.12 micromols g-1 FW), proline (58.70 micromols g-1 FW), malondialdehyde (159.71 nmol g-1 FW), and protein (10.37 %), was observed in the treatment of superabsorbent application along with irrigation after 160 mm. In this study, the simultaneous application of superabsorbent and inoculation with azospirlium showed the highest chlorophyll a (22.25 mg g-1), b content (13.79 mg g-1), carotenoid (29.02 mg g-1), protein (7.99%) and the lowest content of catalase enzyme (39.58 ΔA240 mg-1 protein), The highest soluble sugar content (122.88 micromol g-1 FW) and the lowest amount of malondialdehyde (141.82 nmol g-1 FW) were detected in the treatment of superabsorbent application with Citrobacter. Conclusion: In this study, water deficit had an adverse effect on the physiological properties of castor oil. However, the use of biofertilizers and superplasticizers by improving biochemical and antioxidant properties was able to moderate the effect of drought stress on physiological properties and stabilize photosynthetic pigments, and the stability of photosynthetic pigments can improve photosynthetic properties and plant growth under water deficit conditions. [ABSTRACT FROM AUTHOR]

Controlling or reducing the adsorption of surfactants on reservoir rock surfaces has been a challenging task in enhanced oil recovery (EOR) methods, as it directly affects the cost-effectiveness of the projects. The adsorption of surfactants on rock surfaces can modify their hydrophobicity, surface charge, and other important parameters that govern EOR processes, such as reducing the interfacial tension between water and oil and increasing permeability. Therefore, understanding the adsorption mechanism on rocks is essential for developing alternatives that improve the effectiveness of these processes. In this work, the adsorption of surfactants on carbonate materials was evaluated considering variations in temperature, contact time, and surfactant concentration. The surfactants used were derived from vegetable oils, aiming for a sustainable approach: saponified coconut oil (SCO), saponified babassu coconut oil (SBCO), and saponified castor oil (SMO). The finite bath method was used, resulting in adsorption efficiencies of 85.74%, 82.52%, and 45.30% for SCO, SBCO, and SMO, respectively. The Sips isotherm and the pseudo-second-order model were found to be suitable for characterizing these systems. The simulation of SCO adsorption isotherms on limestone by the Langmuir model was more accurate than that using the Freundlich model. The limestone showed a negative surface charge of approximately −35.0 mV at pH 6.5; this negative charge varied over a wide pH range. These zeta potential data for the samples confirmed that hydrophobic interactions played an important role in the adsorption of the surfactants. Thermodynamic evaluation indicated spontaneous and endothermic adsorption of SCO on limestone. The systems were also characterized by FTIR, TG/DTG, XRD, XRF, SEM, and zeta potential. [ABSTRACT FROM AUTHOR]

The main goal of this study is to make new waterborne polyurethane polymers (WPUCs) using bioresources like curcumin as a chain extender and castor oil as a polyol. We explored different mole ratios of curcumin during the synthesis of WPUC polymers. The WPUC dispersions were well‐defined and had nanoparticle sizes that ranged from 80.1 to 48.2 nm. Their zeta potentials were between −61.7 and − 52.2 mV, which showed that they were more stable. The absence of a phenolic hydroxyl band in the synthesized WPUC's IR spectrum indicated the insertion of curcumin into the PU chain. The coating of WPUCs on polyester/cotton (PE/C) blend fabric showed an improvement in colorfastness properties and reduced air permeability. The enhanced bending modulus (enhanced stiffness), improved abrasion resistance, and higher tensile strength were also observed. Furthermore, the WPUC‐coated fabric samples showed a bacterial inhibition percentage of 83.12%–99.9999% (p < 0.001) compared with blank fabric against bacterias' because of the inherent nature of curcumin. Inserting a higher amount of curcumin in the polymer chain of WPUC improved the antibacterial effects. Overall, our findings provide valuable insights for the possible antibacterial textile applications of synthesized WPUCs. [ABSTRACT FROM AUTHOR]

A thermal conductive structural adhesive (TCSA) plays a crucial role in battery performance and safety. TCSA made of polyurethane (PU) has not only a good thermal conductivity but also good mechanical strength and substrate bonding strength. However, it has to be cost‐effective and easy to be prepared. This work aims to synthesize a series of castor oil‐based PU TCSAs with different amounts of thermal conductive powder using commercially available castor oil polyols, isocyanates, Al2O3, and additives. The shear strength of the TCSA containing 88% thermally conductivity powder reached 5.6 MPa, which was similar to that without the thermal conductivity fillers, but its toughness significantly decreased. Its thermal conductivity was as high as 1.8 W/mK, and it was thermally stable below 270°C. [ABSTRACT FROM AUTHOR]

In recent years, there has been a growing demand for environmentally friendly epoxides made from vegetable oils, including castor oil. This study aims to produce epoxidized castor oil derived ricinoleic acid (ECORA) with applied synergistic sulfate-impregnated zeolite ZM-5 as catalyst. To date, there is no published work on production of ECORA by peracetic acids mechanism using hybrid homogenous–heterogenous catalyst. Peracetic acid produced in situ was used to produce ECORA. By combining acetic acid, which acts as an oxygen carrier, with hydrogen peroxide, which acts as an oxygen donor, peracetic acid was formed. The ratio of ricinoleic acid to acetic acid was used at a ratio of 1:1, while a 1:1 molar ratio of hydrogen peroxide to castor oil was introduced. The epoxidation process has been conducted at a temperature of 55 °C. The mixture was then stirred continuously at a fixed speed of 200 rpm. The maximum conversion to oxirane was achieved at 58%. Overall, ECORA was successfully produced via in situ epoxidation of castor oil with applied hybrid catalyst. [ABSTRACT FROM AUTHOR]

This article aims to study the physical characterization and performance of a material‐based magnetorheological fluid (MRF) dampers for vibration attenuation of a high‐speed rotor–motor system near resonance. Four samples are synthesized by combining electrolytic iron and carbonyl iron (CI) with Castor and Karanja oil and experimentally investigated for their contribution to vibration attenuation. The results demonstrate effective vibration attenuation of the biodegradable oil‐based MRF damper than the nonbiodegradable oil‐based MRF damper. The best vibration attenuation is observed in the case of moderately viscous MRF. CI‐based samples exhibit a lower sedimentation rate, hence recommended for MRF. The vibration amplitude is maximum for the Castor oil‐based MRF damper, however, is minimum for the Karanja oil‐based MRF damper. The steady and transient results of vibration amplitudes are obtained and analyzed for different currents supplied to the MRF damper. The range of unstable speed near resonance is also obtained. The prepared samples show higher attenuation of 6–25% than Sample 5. The vibration amplitude attenuation of Sample 4 and Sample 5 are 47% and 22%, respectively. The findings of this study carry significant implications for controlling the vibration of the dynamic system using an eco‐friendly damping system. [ABSTRACT FROM AUTHOR]

Microemulsions (µEs) are particularly suitable systems for the efficient delivery of anticancer drugs due to their thermodynamic stability, structural flexibility, and patient-friendly chemotherapies. Moreover, µE formulations can efficiently encapsulate the anticancer drugs and deliver them to the desired location. Herein, three new Tween-60-based µE formulations were developed to enhance the dissolution profile of anticancer methotrexate (MTX). For this, µE formulations using an appropriate ratio of castor oil (~9%), water (~11%), and Tween-60 (~40%) were used, while ethanol, 2-propanol, and 1-butanol were selected as co-surfactants for each formulation, respectively. Preliminarily, the phase compatibility of the µE ingredients, the average µE region, and the structural transformation in the microstructure of µE were delineated by mapping the pseudoternary phase diagram, as well as electrical conductivity, viscosity, and optical microscopic measurements. The size distribution profile of the as-formulated µEs analyzed by dynamic light scattering (DLS) revealed the fine monomodal assembly of MTX-µE nanodroplets (~65 nm), which remained stable over a half year of storage. FTIR analysis showed good compatibility of MTX with µE ingredients with no apparent chemical interaction, while fluorescence measurements endorsed the acquisition of MTX in nonpolar microenvironments. Furthermore, an enhanced dissolution rate (>98% ± 1.5%, p ≥ 0.001) and superior bioavailability of the lyophilized non-aggregated methotrexate nanoparticles (MTX-NPs) were achieved, making them a suitable formulation for oral administration. [ABSTRACT FROM AUTHOR]

The combination of modern click protocols and bio‐based building blocks is a great step toward energy‐efficient, and sustainable polymer production. Herein, thiol‐Michael addition (thiol‐yne) reactions from the toolbox of click chemistry protocols are chosen and propiolated castor oil (PCO) is used, a vegetable oil derivative, as the bio‐based building block for the facile functionalization of PCO with various thiols. In addition to the functionalization of PCO, hyperbranched and crosslinked polymers are also prepared. The thiol‐yne click functionalization reactions of the PCO are conducted at room temperature within 5 min and in the presence of an organic catalyst. The yields are found to change between 80% and 99% depending on the type of the thiol compound. The effect of various organic catalysts is investigated, and 1,8‐diazabicyclo(5.4.0)undec‐7‐ene (DBU) is found to be the most effective catalyst for the thiol‐yne modification reactions. The hyperbranched polymer reaches 23.8 kDa (Mw) within 5 min. The findings of this paper open up new horizons for polymer researchers who work in the field of sustainable polymers and click chemistry and the presented idea here is appealing because it offers a potential strategy for fast, reliable, modular, and functional macromolecule preparation from renewable vegetable oils. [ABSTRACT FROM AUTHOR]

Poly (lactic acid) (PLA) compounds with castor oil (CO) and epoxidized castor oil (ECO) were produced via formic acid, with levels of 5% CO, 3 and 5% ECO. The contribution of this study lies in the detailed analysis of thermal degradation and degradation kinetics of PLA/CO and PLA/ECO. Chemical changes were evidenced by Fourier transform infrared (FTIR), thermal stability, and degradation kinetics were investigated by thermogravimetric analysis (TGA), using Friedman (FR), Ozawa–Flynn–Wall (OFW), Kissinger–Akahira–Sunose (KAS) and Vyazovkin (VZ) models. Results showed changes in FTIR spectra for PLA/CO and PLA/ECO. For PLA/5%CO and PLA/3%ECO, lower energy bonds formation were observed, resulting in modifications in the involved molecules and presence of CH type bonds in PLA/5%ECO. TGA analysis showed that PLA presented greater thermal stability compared with PLA/CO and PLA/ECO, with T5% = 306°C. The compounds 5% CO, 3 and 5% ECO exhibited lower degradation temperatures (298, 300, and 296°C), compared with PLA, as well as slower decomposition rates. Kinetic modeling using KAS and OFW models proved to be incapable of describing the degradation kinetics of PLA and its compounds. However, FR and VZ were considered adequate, with discrepancies varying between 7% to −4% and 9% to −3%, which showed higher Ead (215, 185, 210, 189 KJ/mol) at α = 0.3 for PLA. [ABSTRACT FROM AUTHOR]

Background: Polyoxyethylene hydrogenated castor oil (HCO ethoxylates) is a nonionic surfactant used as an excipient for ointments and injections in human and veterinary drugs. Several polyethylene glycol (PEG) derivatives can be obtained depending on the number of moles of ethylene oxide (EO). HCO ethoxylates have the potential to cause anaphylactoid reactions. There is little published information about these types of reactions in dogs. Objective: To determine the potential for HCO‐ethoxylate‐containing drugs to cause anaphylactoid reactions in dogs, employing intradermal testing (IDT) with various concentrations of HCO ethoxylates (HCO‐25, ‐40, ‐60 and ‐80). Animals: Four healthy male laboratory dogs. Materials and Methods: We performed IDT with drugs containing HCO ethoxylates and HCO ethoxylates alone to determine threshold concentrations. The IDT scores and threshold concentrations were compared. Analysis of skin biopsies from IDT sites was used to measure the percentage of degranulated mast cells. The effect of histamine at IDT sites was investigated by pre‐treatment with an antihistamine. Results: All HCO‐ethoxylate‐containing drugs caused a wheal‐and‐flare reaction. The threshold concentrations (0.001% and 0.00001%) of each HCO‐ethoxylate depended on the number of moles of EO (p < 0.05). Mast cell degranulation was enhanced by all HCO ethoxylates. The HCO‐60‐induced reaction was suppressed by an oral antihistamine. Conclusions and Clinical Relevance: The threshold concentration can serve as a consideration for developing safe new drug formulations and for clinical decision‐making around using drugs containing PEG derivatives. IDT is useful to predict the risk of adverse effects. Antihistamines could demonstrate a prophylactic effect. [ABSTRACT FROM AUTHOR]

This paper introduces a cheap local Ricinus communis, which grows in Jahrom, a warm region of southwest Iran, as a renewable energy source. Biodiesel production was investigated by employing CaO and C:CaO as heterogeneous catalysts and KOH as a homogenous catalyst. Conventional and ultrasonic-assisted methods were used considering different methanol to oil molar ratios (4:1, 6:1 and 8:1) and different temperatures (40°C, 50°C and 60°C). The optimized production condition was assessed by response surface methodology (RSM). The results showed that the most suitable catalyst was C:CaO with a methanol to oil molar ratio of 6:1 and temperature of 60°C. Using carbon with CaO increased biodiesel yield by around 20% compared to CaO alone. In all conditions, ultrasonic assistance improved biodiesel yield compared to the conventional method by around 11%. Furthermore, the biodiesel content increased with increasing ultrasonic power from 100 to 400 W. The properties of the produced biodiesel from Iranian castor oil meet the requirements of the EN 14214 biodiesel standard. Optimization of the biodiesel production under ultrasonic condition using RSM shows that the best temperature is 46.81°C and the methanol to oil molar ratio is 5.25 by Cao:C catalyst. [ABSTRACT FROM AUTHOR]

The aim of the work is to develop two functionalized castor oil-based polyglycidyl ethers containing benzene rings by ring-opening etherification and alkylation reaction, respectively: phenoxy castor oil-based polyglycidyl ether (POCOGE) and phenolic castor oil-based polyglycidyl ether (PCOGE). Castor oil-based polyglycidyl ethers were introduced into E-51, which is a common type of bisphenol A epoxy resin. The thermomechanical performances of the polymer blends were evaluated. The addition of the synthetic castor oil-based polyglycidyl ethers showed an enhancement of E-51 in both toughness and flexibility without sacrificing bending strength. The tensile strength reached 81.0 MPa and 86.4 MPa, which were 26.5% and 34.9% higher compared to that of pure E-51. Meanwhile, the impact strength reached 28.1 kJ m−2 and 19.4 kJ m−2, an increase of 147% and 70.3%, respectively, compared with E-51. Scanning Electron Microscope (SEM) graphics exhibited those cured polymers had ductile fracture. The non-isothermal curing kinetics of different curing systems were analyzed by Málek's method and conformed to the Šesták–Berggren SB(m,n) model. This study aims to address the inadequate stiffness of bio-based epoxy resins and extend the scope of bio-based epoxy resins with versatile functionality. [ABSTRACT FROM AUTHOR]

This study analysed and discussed the friction and wear properties, as well as the interface evolution behaviour of polycrystalline diamond compact (PDC) under various base oils, through conducting friction experiments on PDC/Si3N4 with different base oils. The friction and lubrication mechanism of PDC under different base oils were examined using scanning electron microscopy (SEM), x‐ray energy dispersive spectrometry (EDS), three‐dimensional white light interferometry, and Raman spectroscopy. The results of the study demonstrated that PDC exhibited the best friction and wear performance when lubricated with synthetic oil PAO, followed by castor oil. The inferior performance of paraffin oil can be attributed to its low viscosity, resulting in a lower presence of ions capable of passivating the carbon dangling bond. Consequently, paraffin oil displayed inadequate oxidation stability and increased susceptibility to oil film destruction, ultimately leading to suboptimal friction and wear characteristics. Overall, this study provides valuable insights for industrial applications, aiding in the selection of appropriate base oils as cutting fluids for PDC cutting tools and enhancing the friction and wear properties of PDC. [ABSTRACT FROM AUTHOR]

This study specifically examines the process of producing and analyzing biodiesel made from castor oil using base-catalyzed transesterification. The catalyst used in this process is potassium hydroxide (KOH), and the methanol (CH3OH) used has a purity of 99.9%. The biodiesel obtained was analyzed extensively to assess its quality. The characterization techniques employed were Gas Chromatography (GC) for compositional analysis, Flash Point measurement for safety assessment, Kinematic Viscosity evaluation for flow properties, and Density determination for mass-volume relationships. To perform a statistical analysis, the Response Surface Method (RSM) was employed to determine the optimal conditions that would yield the highest rate of biodiesel production among the potential solutions. This study focused on three key variables affecting the transesterification process: ultrasonic duty cycle (using a 24 kHz ultrasonic method varying the duty cycle from 20% to 100%), ultrasonic amplitude (varying from 20% to 100%), and reaction time (spanning from 10 to 15 minutes). This investigation achieved a biodiesel yield of 88.38% using a 60% ultrasonic amplitude, a single ultrasonic cycle, and a 15-minute reaction time. The regression model developed can be used to predict biodiesel's percentage conversion. [ABSTRACT FROM AUTHOR]

The objective of this study is to assess, characterize, and forecast the aging effects on the mechanical properties of a vegetable‐based polyurethane foam (PUF) derived from castor oil under elevated relative humidity conditions and at two distinct load orientations (aligned with the expansion direction and perpendicular to it). Ten specimens were subjected to temperatures of 60, 75, and 90°C, along with a relative humidity of 90%, for a duration of up to 60 days. Compression tests, following ASTM D1621‐16 standards and supplemented by 3D digital image correlation, revealed nearly isotropic behavior with marginally lower compression strength in the expansion direction. On the other hand, the strength of the foams at 90°C was higher in that direction. This led to a smaller activation energy (Ea) in this property, which ended up showing a shorter lifespan prediction considering the strength retention in this direction. The stiffness values were proportionally more similar in both directions than the strength ones and this was observed in the Ea for those curves. In contrast to several other foams and polyurethanes, the one examined in this study exhibited consistently higher Ea values for its mechanical properties, particularly in the transverse direction to expansion, surpassing 94 kJ/mol. This indicates a robust diffusion and chemical stability, suggesting its potential for prolonged utilization compared to conventional oil‐based foams. A prediction was made that this foam would lose 50% of its stiffness and strength in around 9.8 and 9.5 years at 20°C, respectively, considering the directions more sensitive to the aging process. This research offers valuable insights for predicting lifespan based on operating temperatures and property retention needs, contributing to the advancement of sustainable materials in structural applications. Highlights: Fifty specimens investigated for each of two directions.Evaluation of vegetable‐based PUF aging process unveils density changes.Unique behavior noted: different Ea values for each direction.High Ea values indicate enhanced mechanical stability over oil‐based foams.Lifespan prediction enhances material application prospects. [ABSTRACT FROM AUTHOR]

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The experiment on biological activity of botanical oils and leaf powders against R. dominica was conducted under laboratory condition. The results revealed that among the botanical oils and leaf powder, the castor oil 2.0% and neem leaf powder 1% achieved maximum adult mortality at 72 hr after treatment (91.67% and 81.67%) and revealed as the best grain protectants with least seed damage (4.33% and 3.67%), weight loss (2.01% and 1.04%), F1 adult emergence (3.67 and 4.33) and high inhibition rate (97.25% and 97.34%). This is due to their high viscosity of oils and asphyxiation effect by leaf powders. The finding also revealed that the botanical oils and leaf powders do not affect the germination of wheat seed. [ABSTRACT FROM AUTHOR]

A rapid and simple method for the determination of stearic acid and 12-hydroxystearic acid in PEG-60 hydrogenated castor oil by high performance liquid chromatography with evaporative light scattering detection was established. The oil sample was first pretreated by alkaline hydrolysis. The analysis was performed on a Zhongpu Develop XD-C18 column (250 mm × 4.6 mm, 5 µm) with gradient elution of methanol and 1% acetic acid aqueous solution at a flow rate of 1.2 mL·min−1 and a column temperature of 40 °C. The drift tube temperature of the evaporative light scattering detection system was set at 40 °C, and the pressure of carrier gas (N2) was 337 kPa. The regression equation revealed a good linear relation (r = 0.9993–0.9995) during the test ranges (119.1–1190.7 μg·mL−1 for 12-hydroxystearic acid, 10.7–107.4 μg·mL−1 for stearic acid). The detection limits of 12-hydroxystearic acid and stearic acid were 1.1 and 2.5 μg·mL−1, the limits of quantitation were 3.2 and 7.4 μg·mL−1, respectively. And the mean recoveries were 101.5 and 101.0%, the corresponding relative standard deviations (RSDs) were 2.1 and 2.8%, respectively. The RSDs corresponding to repeatability (n = 6) were both less than 1.7% in terms of precision. As to the stability, the test results remained stable after 8 h at room temperature (RSDs were both less than 2.6%). The developed method showed high sensitivity, recovery, repeatability and stability, which indicated that the method could be applied as a quality evaluation method for the determination of stearic acid and 12-hydroxyoctadecanoic acid in PEG-60 hydrogenated castor oil. [ABSTRACT FROM AUTHOR]

In this article, the degradability by Aspergillus niger and Aspergillus clavatus of three bio-based polyurethane (PU) foams is compared to previous degradability studies involving a Pseudomonas sp. bacterium and similar initial materials (Spontón et al. in Int. Biodet. Biodeg. 85:85–94, 2013, https://doi.org/10.1016/j.ibiod.2013.05.019). First, three new polyester-polyurethane foams were prepared from mixtures of castor oil (CO), maleated castor oil (MACO), toluene diisocyanate (TDI), and water. Then, their degradation tests were carried out in an aqueous medium, and employing the two mentioned fungi, after their isolation from the environment. From the degradation tests, the following was observed: (a) the insoluble (and slightly collapsed) foams exhibited free hydroxyl, carboxyl, and amine moieties; and (b) the water soluble (and low molar mass) compounds contained amines, carboxylic acids, and glycerol. The most degraded foam contained the highest amount of MACO, and therefore the highest concentration of hydrolytic bonds. A basic biodegradation mechanism was proposed that involves hydrolysis and oxidation reactions. [ABSTRACT FROM AUTHOR]

The tests revealed the exceptional combustion properties of a blended fuel consisting of castor oil and rhodium liquid (Rhl) as a highly effective homogeneous combustion catalyst. Our findings indicate that castor oil's unique molecular structure makes it an ideal fuel component, and the catalyst interacts with the fuel's triglycerides to enhance fuel properties and facilitate ignition.These findings support the pivotal role of the synthetic catalyst Rhl, which effectively reduces the binding forces within the triglyceride chain through polarization interactions. As a result, molecular bonds become more flexible, providing electrons with greater freedom of movement. Synthetic catalysts induce significant modifications in the triglyceride structure, increasing electron energy levels and enhancing the reactivity of fuel molecules, ultimately leading to improved fuel combustion efficiency. Integrating the Rhl synthetic catalyst also enhances fuel performance by reducing ignition duration and increasing the combustion rate. The elevated combustion temperatures of the fuel droplets highlight the effectiveness of promoting environmentally sustainable combustion processes.

Abstract Biodegradable plastics are those subjected easily to a degradation process, in which they can be decomposed after disposal in the environment through microbial activity. 30 bioplastic film formulations based only on chitosan film were used in the current investigation as a positive control together with chitosan film recovered from chitin-waste of locally obtained Aristeus antennatus. Additionally, castor oil was used as a plasticizer. While the yield of chitosan was 18% with 7.65% moisture content and 32.27% ash in the shells, the isolated chitin had a degree of deacetylation (DD) of 86%. The synthesized bioplastic films were characterized via numerous criteria. Firstly, the swelling capacity of these biofilms recorded relatively high percentages compared to polypropylene as synthetic plastic. Noticeably, the FTIR profiles, besides DSC, TGA, and XRD, confirmed the acceptable characteristics of these biofilms. In addition, their SEM illustrated the homogeneity and continuity with a few straps of the chitosan film and showed the homogeneous mixes of chitosan and castor oil with 5 and 20%. Moreover, data detected the antibacterial activity of different bioplastic formulas against some common bacterial pathogens (Enterococcus feacalis, Kelbsiella pnumina, Bacillus subtilis, and Pseudomonas aeruginosa). Amazingly, our bioplastic films have conducted potent antimicrobial activities. So, they may be promising in such a direction. Further, the biodegradability efficacy of bioplastic films formed was proved in numerous environments for several weeks of incubation. However, all bioplastic films decreased in their weights and changed in their colors, while polypropylene, was very constant all the time. The current findings suggest that our biofilms may be promising for many applications, especially in the field of food package protecting the food, and preventing microbial contamination, consequently, it may help in extending the shelf life of products.

Abstract New castor oil/polyethylene glycol (CAO/PEG) hybrids were synthesized by reacting of CAO with PEG 300, 600, 1000, 2000 or 4000, in presence of ammonium per sulfate (APS) as an initiator. The optimum conditions to synthesis such hybrids are: PEG/CAO weight ratio, 35%; APS/PEG weight ratio, 15%; reaction temperature, 80 °C; and reaction time, 60 min. Only the hybrids based on PEG 1000 and 2000 formed oil in water stable emulsions. Treating cotton fabric samples with easy care finishing formulation containing 40 g/L of the synthesized hybrids emulsions results in an enhancement in softness, tensile strength, whiteness index, and stiffness along with a reduction in nitrogen content, wrinkle recovery angle, and wettability properties of treated fabric, compared to that sample finished in absence of that emulsions. The chemical structure of the synthesized CAO/PEG1000 hybrid was confirmed via the FTIR and 1HNMRanalysis whereas the TEM analysis showed that the particles size of that hybrid emulsion is in the range of 27–105 nm. Moreover, such hybrid emulsion treated fabric surface was characterized via SEM and EDX analysis. Furthermore, treating dyed samples with the nominated hybrid emulsion improves the color strength of that samples but keeps the washing fastness, wet rubbing fastness as well as alkaline perspiration fastness of the dyed/finished samples unchanged. The wet rubbing fastness and alkaline perspiration fastness of all the dyed/finished samples were enhanced while the light fastness of such samples decreased.

Conventional plasticizers deteriorate mechanical and viscoelastic properties of the propellants due to their migration upon aging and long-term storage, which affects reliability and safety properties during exploitation. To address this issue, conventional plasticizer, dioctyl adipate (DOA), is replaced by reactive one, castor oil (CO). In addition, three different types of HTPB were used to obtain propellants with designed viscoelastic and mechanical properties. The CO increased propellants viscosity, without a significant impact on the propellant processability, regardless to the type of prepolymer. Conversely, mechanical properties were different depending on the type of resin, which were further analyzed by gel permeation chromatography (GPC). Addition of CO formed a denser polymer network and shifted Tg to higher values, compared to the compositions with DOA. The tensile strength of CO-containing propellants was lower at +20 °C and +50 °C compared to the reference compositions, while the strain at maximum load and strain at break were significantly increased with pronounced plastic deformation, especially for samples at −30 °C. The inclusion of CO in the propellants composition gives more room for adjusting a wide range of mechanical properties.

Akeberegn Gorems Ayele, Jeylan Sinba Kawet Department of Pharmacology and Clinical Pharmacy, School of Pharmacy, College of Health Sciences, Addis Ababa University, Addis Ababa, EthiopiaCorrespondence: Akeberegn Gorems Ayele, Department of Pharmacology and Clinical Pharmacy, School of Pharmacy, College of Health Sciences, Addis Ababa University, Zambia Street, PO Box 9086, Addis Ababa, Ethiopia, Tel +251985408322, Email Akeberegn.gorems@aau.edu.etBackground: People frequently complain of long-term constipation. The cost associated with using modern medications to treat constipation is significant, and the probability of encountering side effects is notably high. These limitations restrict their effectiveness in therapy, remain unresolved, and underscore the need for research on alternative therapeutic approaches. Plants of the genus Artemisia have been used to treat constipation. Therefore, the aim of this study was to evaluate the laxative effects of aqueous A. abyssinica leaf and stem extracts of Artemisia abyssinica in mice.Methods: The laxative activity of A. abyssinica leaf and stem extracts was evaluated using three models: laxative activity, gastrointestinal motility, and gastrointestinal secretion. In this study, bisacodyl was used as a standard laxative and loperamide was used to induce constipation.Results: In the laxative test, 200 (P< 0.05) and 400 mg/kg (p< 0.01) doses of plant extract significantly increased the percentage of fecal water content. Moreover, the highest dose of extract increased the frequency of defecation after 12 h (p< 0.05). In the remaining two models, the experimental plans also showed significantly higher gastrointestinal motility and noticeable accumulation of intestinal fluid.Conclusion: The results of this study indicate that aqueous leaf and stem extracts of A. abyssinica have laxative effects.Keywords: laxative, constipation, Artemisia abyssinica, castor oil, loperamide

Abstract This article presents the results of an experiment designed to study the impact of temperature on the characteristic parameters of creeping discharges. The insulating interfaces consist of a thermally enhanced cellulose surface immersed in mineral oil, palm kernel oil methyl ester (PKOME) and castor oil methyl ester (COME). The study was carried out under a standard negative lightning impulse voltage (1.2/50 μs). The article also presents the complete algorithms for calculating the maximum extension of the discharges, the ionisation rate and the charge produced by them. The results of the study show that temperature favors the propagation of discharges and the ionisation rate. It was observed that liquids with a higher dielectric constant and high electrical conductivity were more exposed to the impact of temperature. The results show ionisation increments of 0.973%/°C, 1.093%/°C and 1.076%/°C in mineral oil (MO), COME and PKOME respectively. The maximum extension of the discharges shows a linear evolution with the applied voltage and temperature but a non-linear increment with the temperature. As for the charge produced, it shows a constant increment with temperature and voltage in each liquid. These values are (5.839%/°C, 1.977%/kV), (6.047%/°C, 2.082%/kV) and (6.177%/°C, 2.113%/kV) respectively in MO, COME and PKOME.