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AbstractCircular feeds, such as grain dry distillers, citrus pulp, cane molasses, and potatoes peels, are co-products of biomass processes. They are currently proposed in animal nutrition to improve the environmental and economic sustainability of the food production chain. In this paper, we report a case study involving fipronil, a pesticide currently not authorized for agriculture within the EU, but used in the Americas, Eastern Europe, and Asia. Fipronil was found at a mean level of 0.49 mg/kg, in a grain dry distiller batch administered to dairy cows. This finding, along with other evidence of potential fipronil presence in feed materials, prompted us to evaluate the risk to food safety and food security from 12 different conventional and sustainable feeding regimens. To this purpose, we considered a fipronil feed-to-milk carry-over rate of 0.52, the tolerance levels in fodders and food from The EU, Codex Alimentarius, and US-EPA, and the Acceptable Daily Intake (ADI) of 0.0002 mg/kg body weight for adverse effects on thyroid function in dairy cows. Under a conservative scenario, fipronil-contaminated potato peels and grain distillers in the feeding regimens may play a pivotal role in exceeding the EU Maximum Residue Level (MRL) in bovine milk and fat (0.005 and 0.030 mg/kg, respectively). Hay-based diets with soybean hulls and cane molasses show negligible risks (Hazard Index ∼ 1). In all cases, the ADI exceedance suggests the need to evaluate thyroid function in dairy cows exposed to fipronil as a food security factor. [ABSTRACT FROM AUTHOR]

Grape seed oil (GSO) is a valuable resource for the pharmaceutical, cosmetic, and food industries due to its fatty acid composition, which provides anti-inflammatory, cardioprotective, antimicrobial, and anticancer properties. GSO is also recognized for its sensory attributes and serves as an essential component in our dietary intake, providing vital fatty acids for metabolic reactions. The enzymatic synthesis of structured lipids (SL) using GSO was investigated in this study. The SL was created by incorporating medium chain fatty acids (capric acid – C10) at the sn -1 and sn -3 positions and long chain fatty acids in the internal position of the triacylglycerols (TAG). GSO was selected based on its composition rich in unsaturated fatty acids, mainly linoleic acid. The acidolysis reactions were catalyzed by an immobilized commercial lipase Lipozyme TLIM®. The incorporation degree of C10 into GSO reached 36%. Health lipid indices were calculated to determine the C10 incorporation effect on the improvement of nutritional quality of oil. The SL showed lower oxidative stability index (OSI) values than the original oil and higher degree of fatty acid (DFA) values. The simpler, solvent-free method not only enhances the health benefits of oils but also gives valuable properties to GSO, making it an even more attractive option for food industries. [Display omitted] • Sustainable green processes for valorization of grape seed are proposed. • Enzymatic synthesis of structured lipids enhances GSO with health promoting C10 fatty acids. • Lipozyme TLIM¬Æ achieved a remarkable 36% C10 incorporation in GSO. • Simpler, solvent-free method improves GSO's health lipid indices, making it an ideal choice for food industries. [ABSTRACT FROM AUTHOR]

Background Occupational short-latency respiratory disease (SLRD; predominantly asthma, rhinitis, hypersensitivity pneumonitis, and occupational infections) prevalence is difficult to determine but certain occupations may be associated with increased susceptibility. Aims This study aimed to examine which occupations and industries are currently at high risk for SLRD and determine their respective suspected causal agents. Methods SLRD cases reported to the SWORD scheme between 1999 and 2019 were analysed to determine directly standardized rate ratios (SRR) by occupation against the average rate for all other occupations combined. Results 'Bakers and flour confectioners' and 'vehicle spray painters' showed significantly raised SRR for SLRD in general, mostly due to occupational rhinitis (234.4; 95% CI 200.5–274.0) and asthma (63.5; 95% CI 51.5–78.3), respectively. Laboratory technicians also showed significantly raised SRR for occupational rhinitis (18.7; 95% CI 15.1–23.1), primarily caused by laboratory animals and insects. Metal machining setters and setter-operators showed increased SRR for occupational hypersensitivity pneumonitis (42.0; 95% CI 29.3–60.3), largely due to cutting/soluble oils. The occupation mostly affected by infectious disease was welding trades (12.9; 95% CI 5.7–29.3), mainly attributable to microbial pathogenicity. Conclusions This study identified the occupational groups at increased risk of developing an SLRD based on data recorded over a recent two-decade period in the UK. Occupational asthma and rhinitis were identified as the prevailing conditions and hypersensitivity pneumonitis as a potentially rising respiratory problem in the metalworking industry. [ABSTRACT FROM AUTHOR]

This systematic review and meta‐analysis aimed to consolidate evidence on dietary interventions for atopic eczema/dermatitis (AD) skin symptoms in children without food allergies, following PRISMA 2020 guidelines. Systematic review updates were conducted in May 2022 and June 2023, focusing on randomized placebo‐controlled trials (RCTs) involving children with AD but without food allergies. Specific diets or supplements, such as vitamins, minerals, probiotics, prebiotics, symbiotics, or postbiotics, were explored in these trials. Exclusions comprised descriptive studies, systematic reviews, meta‐analyses, letters, case reports, studies involving elimination diets, and those reporting on food allergens in children and adolescents. Additionally, studies assessing exacerbation of AD due to food allergy/sensitization and those evaluating elimination diets' effects on AD were excluded. Nutritional supplementation studies were eligible regardless of sensitization profile. Evaluation of their impact on AD clinical expression was performed using SCORAD scores, and a meta‐analysis of SCORAD outcomes was conducted using random‐effect models (CRD42022328702). The review encompassed 27 RCTs examining prebiotics, Vitamin D, evening primrose oil, and substituting cow's milk formula with partially hydrolyzed whey milk formula. A meta‐analysis of 20 RCTs assessing probiotics, alone or combined with prebiotics, revealed a significant reduction in SCORAD scores, suggesting a consistent trend in alleviating AD symptoms in children without food allergies. Nonetheless, evidence for other dietary interventions remains limited, underscoring the necessity for well‐designed intervention studies targeting multiple factors to understand etiological interactions and propose reliable manipulation strategies. [ABSTRACT FROM AUTHOR]

We have carried out a correlation analysis to study relationships between the trace element (TE) composition of mud-volcanic and carbon dioxide fluids in the Greater Caucasus on the one hand and the chemical composition of upper, middle, and lower crust, as well as various kinds of biota on the other hand. It has turned out to be possible to relate the roots of the associated fluid flows with definite stages of the Earth's crust, as well as to point out, in several cases, the kind of the dominant original organic matter. The roots of both carbon dioxide fluids and mud-volcanic fluids were shown to reside in the middle crust. We have compared correlative relationships for deep-seated fluids in the Caucasus with those for oils in several major oil-gas basins in Russia and in the fluid systems of Kamchatka. [ABSTRACT FROM AUTHOR]

Omega‐3 fatty acid supplements, such as fish oil and plant‐based oils, have gained popularity because of their potential health benefits. However, the quality and composition of these supplements can vary widely, particularly in terms of the two main forms of omega‐3 fatty acids: triacylglycerols (TAGs) and ethyl esters (EEs). TAGs are the natural form found in fish oil but are prone to oxidation, whereas EEs are more stable but less well absorbed by the body. Differentiating between these forms is crucial for assessing the efficacy and tolerance of omega‐3 supplements. This article describes a novel approach to differentiate between TAG and EE forms of omega‐3 fatty acids in dietary supplements, utilizing a 60‐MHz benchtop nuclear magnetic resonance (NMR) spectrometer. The proposed method using 1H and 1H‐1H COSY NMR provides a quick and accurate approach to screen the forms of omega‐3 fatty acids and evaluate their ratios. The presence of diacylglycerol (DAGs) in some supplements was also highlighted by this method and adds some information about the process used (i.e., esterification/enrichment). The affordability and user‐friendliness of benchtop NMR equipment make this method feasible for food processing companies or quality control laboratories. In this study, 24 oil supplements were analyzed using NMR analysis in order to demonstrate the potential of this method for the differentiation of TAG and EE forms in omega‐3 supplements. [ABSTRACT FROM AUTHOR]

Introduction: There are several oral diseases caused by various microorganisms. In this work, we discuss periodontal pathogens, which cause chronic degenerative damage in the supporting tissues of teeth. This is why several treatments have been developed for their eradication, including phytocomponents and essential oils as an option in antimicrobial therapy. Objective: The aim of this study was to determine the inhibitory effect of the essential oil of the plant species Schinus molle L. native to Ecuador on strain of Porphyromonas gingivalis at different concentrations. Methodology: This was a laboratory and longitudinal study in which the Porphyromonas gingivalis ATCC 33277 strain was cultured in 20 Petri dishes, working with several exposure subgroups, including Group 1 - 50% essential oil of Schinus molle leaves; Group 2 - 100% essential oil of Schinus molle L.; Group 3 - 0.12% chlorhexidine (positive control); Group 4 - saline solution (negative control) with different incubation periods of 24 and 72 hours. Results: The Porphyromonas gingivalis ATCC 33277 sample exposed to 100% plant species Schinus molle L. for 24 hours had an inhibition zone of 15 mm, demonstrating high sensitivity, and exposure for 72 hours produced a zone of 14 mm, also suggesting sensitivity. Exposure to S. molle L. at 50% for 24 hours produced a zone of inhibition of 9.65 mm, showing sensitivity; however, it is worthwhile to continue developing and evaluating this area of study. Conclusions: This study demonstrates that phytotherapy using the essential oil of the plant species Schinus molle L. represents a therapeutic option in cases of infections caused by Porphyromonas gingivalis. [ABSTRACT FROM AUTHOR]

Background: Herbal medicine and its bioproducts are rich in bioactive compounds that promising in drug development. These phytochemical constituents may be secondary metabolites that exert high potency. Materials and Methods: This study investigated the phyto-constituents bioactive compounds from the aerial parts of some Saudi medicinal plants using n-hexane extracts (Trichodesma trichodesmoides, Baccharoides schimperi, Anabasis articulate and Achillea fragrantissima) and a mixture of essentials oils in equal ratio (Arnica montana, Chamomile, Salvia officinalis, Oenothera, Walnut leaves and Flaxseed) using GC-MS. Results: The GC-MS analysis of plants and essentials oils revealed the presence of various compounds like terpenoids and vitamins related to its anti-microbial activity, antioxidant and anti-inflammatory activity. Conclusion: It was concluded that, the broad range of terpenoids and vitamins are the main components in the hexane extract. These possess different biological activities. Further studies will be carried out in vivo and in vitro to identify the mechanism of action via signaling pathway. [ABSTRACT FROM AUTHOR]

Introduction: The use of natural products such as essential oils has been suggested due to their promising pharmacological effects and economic viability. This study aimed to determine hydrogenic potential (pH), titratable acidity (TA), and ion concentrations of five solutions containing essential oils (EO), when used as a EO-containing solutions, and evaluate ion concentrations, enamel surface loss, and morphology alterations in enamel. Materials and methods: The pH, TA, calcium (Ca), potassium (K), and sodium (Na) concentrations of five EO-containing solutions were measured. Bovine enamel specimens were submitted to two daily 30-s immersions in artificial saliva, citric acid, distilled water, BaCloTea (Basil, Clove e Tea Tree), GeLaTeaPep (Geranium, Lavender, Tea Tree and Peppermint), EucaLem (Eucalyptus and Lemon), Cinnamon, or Spearmint solutions for 14 days. Ca, K, Na, and phosphorus (P) were quantified through ions chromatography, enamel surface loss was determined by profilometry, and surface morphology was qualitatively analyzed through scanning electron microscopy. Data were submitted to one-way ANOVA and Tukey (p < 0.05). Results: The five EO-containing solutions presented significantly lower pH values than distilled water (p < 0.05). The GeLaTeaPep group presented a significantly higher TA value than BaCloTea (p < 0.05), which in turn showed a significantly higher TA value than the other solutions (p < 0.05). The distilled water presented significantly higher Ca, K, and Na concentrations than all EO-containing solutions (p < 0.05). The enamel exposed to EO-containing solutions showed lower Ca and P concentrations than artificial saliva (control) as well as significantly higher surface loss; however, the surface morphology was similar to the artificial saliva. Conclusion: EO-containing solutions have low pH, TA, and low concentrations of Ca, Na, and K. Moreover, enamel exposed to these solutions showed low Ca and P concentrations and slight surface loss without morphology alteration. [ABSTRACT FROM AUTHOR]

Bioactive compounds extracted from plum seeds were identified and quantified, aiming to establish how the brandy manufacturing process affects the properties and possible cascade valorization of seed residues. Extraction with n-hexane using Soxhlet has provided oils rich in unsaturated fatty acids (92.24–92.51%), mainly oleic acid (72–75.56%), which is characterized by its heart-healthy properties. The fat extracts also contain tocopherols with antioxidant and anti-inflammatory properties. All the ethanol–water extracts of the defatted seeds contain neochlorogenic acid (90–368 µg·g−1), chlorogenic acid (36.1–117 µg·g−1), and protocatechuate (31.8–100 µg·g−1) that have an impact on bioactive properties such as antimicrobial and antioxidant. Anti-amyloidogenic activity (25 mg·mL−1) was observed in the after both fermentation and distillation extract, which may be related to high levels of caffeic acid (64 ± 10 µg·g−1). The principal component analysis showed that all plum seed oils could have potential applications in the food industry as edible oils or in the cosmetic industry as an active ingredient in anti-aging and anti-stain cosmetics, among others. Furthermore, defatted seeds, after both fermentation and distillation, showed the greatest applicability in the food and nutraceutical industry as a food supplement or as an additive in the design of active packaging. [ABSTRACT FROM AUTHOR]

Introduction. The control and monitoring of Polycyclic Aromatic Hydrocarbons (PAHs) is still not a permanent concern for environmental quality regulatory institutions in many parts of the world. That is why it is necessary to pay attention to this unresolved issue. Objective. In our work, the presence of PAHs in edible oils, and recovered motor oils, diesel fuel, lubricating oils, is determined to call attention to these substances, of systematic use in human activity, as an alert of consideration for food safety and in general for the guarantee of an environmentally and physically healthy life. Materials and methods. The identification of PAHs was carried out by High-Performance Liquid Chromatography (HPLC), comparing the chromatogram of the standard with that of the samples analyzed. Results. The significant presence of PAHs in petroleum derivatives and edible oils is demonstrated. Conclusions. All of the above requires the attention of the regulatory authorities of environmental and health quality for the sustainable conservation of life. [ABSTRACT FROM AUTHOR]

Recent studies have demonstrated that Sirtuin-1 (SIRT-1)-activating molecules exert a protective role in degenerative ocular diseases. However, these molecules hardly reach the back of the eye due to poor solubility in aqueous environments and low bioavailability after topical application on the eye's surface. Such hindrances, combined with stability issues, call for the need for innovative delivery strategies. Within this context, the development of self-nanoemulsifying drug delivery systems (SNEDDS) for SIRT-1 delivery can represent a promising approach. The aim of the work was to design and optimize SNEDDS for the ocular delivery of two natural SIRT-1 agonists, resveratrol (RSV) and melatonin (MEL), with potential implications for treating diabetic retinopathy. Pre-formulation studies were performed by a Design of Experiment (DoE) approach to construct the ternary phase diagram. The optimization phase was carried out using Response Surface Methodology (RSM). Four types of SNEDDS consisting of different surfactants (Tween® 80, Tween® 20, Solutol® HS15, and Cremophor® EL) were optimized to achieve the best physico-chemical parameters for ocular application. Stability tests indicated that SNEDDS produced with Tween® 80 was the formulation that best preserved the stability of molecules, and so it was, therefore, selected for further technological studies. The optimized formulation was prepared with Capryol® PGMC, Tween® 80, and Transcutol® P and loaded with RSV or MEL. The SNEDDS were evaluated for other parameters, such as the mean size (found to be ˂50 nm), size homogeneity (PDI < 0.2), emulsion time (around 40 s), transparency, drug content (>90%), mucoadhesion strength, in vitro drug release, pH and osmolarity, stability to dilution, and cloud point. Finally, an in vitro evaluation was performed on a rabbit corneal epithelial cell line (SIRC) to assess their cytocompatibility. The overall results suggest that SNEDDS can be used as promising nanocarriers for the ocular drug delivery of RSV and MEL. [ABSTRACT FROM AUTHOR]

The existing treatise targeted to compare the effects of adding different nano-emulsions essential oils (olive, flaxseed, and grapeseed oils) in freezing extender on semen quality and freezability in buffalo. Nano-emulsions were prepared from olive, flaxseed, and grapeseed oils and characterized for their sizes and shapes. Semen extended in four tubes were supplemented with 0 (control) and 3.5% nanoemulsion oils, including olive (NEO), flaxseed (NEFO) and grape seed oils (NEGSO) respectively. NEGSO resulted in the highest (p < 0.05) membrane integrity, vitality, progressive motility (P-motility) of sperm compared to the other groups in post-thawed buffalo bull semen (at 37 °C for 30 s). The addition of NEGSO had the best results for membrane integrity, progressive motility, and vitality of sperm after incubation (at 37 °C and 5% CO 2 for 2 h). A superior (p < 0.05) value of total antioxidant capacity in frozen-thawed spermatozoa was monitored in all supplemented groups as relative to the control. The values of malondialdehyde (MDA) and nitric oxide (NO) were lower (p < 0.05) in NEGSO group compared with other groups. Both NEO and NEFO exhibited the same results for MDA, and NO levels (p > 0.05). All supplemented groups exhibited lower hydrogen peroxide levels (p < 0.05) as relative to the un-treated group. The lowest (p < 0.05) caspase 3 levels were verified in NEGSO treatment, followed by NEFO and NEO treatments. Post-thawed sperm showed ultrastructural damages in the control group, and theses damages were attenuated or resorted by the NEGSO, NEFO and NEO supplemented to freezing extender. In consequences with in vitro results regarding the sperm attribute, a greater pregnancy rate (92%) was observed in NEGSO group as compared with NEFO (88%), NEO (76%) and CON (68%) groups. Our findings demonstrate that NEGSO (3.5%) could be used as a new strategy in enhancing sperm functionality, potential fertility and reducing the oxidative damage and apoptosis markers. This could be significantly applicable for sperm physiology cryopreservation in the milieu of assisted reproduction systems. • Adding of different nano-emuslion essential oils in freezing extender improving the semen quality, and freezability in buffalo. • The addition of NEGSO had the best results for sperm quality and pregnancy rates. • All supplemented nano-emuslion essential oils reduced the oxidative stress and boosting the anti-oxidative markers. • Nano-emulsion essential oils can enhance the sperm functionality, potential fertility and reducing the oxidative damage and apoptosis markers. [ABSTRACT FROM AUTHOR]

Lipids are a concentrated source of energy with at least twice as much energy as the same amount of carbohydrates and protein. Dietary lipids provide a practical alternative toward increasing the dietary energy density of feeds for high‐performing modern broilers. However, the digestion and absorption of dietary lipids are much more complex than that of the other macronutrients. In addition, young birds are physiologically limited in their capacity to utilise dietary fats and oils effectively. The use of dietary emulsifiers as one of the strategies aimed at improving fat utilisation has been reported to elicit several physiological responses including improved fat digestibility and growth performance. In practical terms, this allows for the incorporation of lipids into lower‐energy diets without compromising broiler performance. Such an approach may potentially lower feed costs and raise revenue gains. The current review revisits lipids and the different roles that they perform in diets and whole‐body metabolism. Additional information on the process of dietary lipid digestion and absorption in poultry; and the physiological limitation brought about by age on lipid utilisation in the avian gastrointestinal tract have been discussed. Subsequently, the physiological responses resulting from the dietary supplementation of exogenous emulsifiers as a strategy for improved lipid utilisation in broiler nutrition are appraised. Suggestions of nascent areas for a better understanding of exogenous emulsifiers have been highlighted. [ABSTRACT FROM AUTHOR]

Essential oils have antioxidant and antimicrobial properties, so it is considered one of the most suitable methods to maintain overall fruit quality, reduce decay and extend the shelf life of fruit during storage. Therefore, two experiments using fruits harvested from 14-year-old guava trees in a private farm located in Al-Busayli village, Rashied, Bohaira governorate, Egypt, during the 2021and 2022 seasons. The primary objective was to evaluate the influence of essential oils on the overall quality and extension of the shelf-life of winter guava fruit. The fruits were subjected to various treatments, including dipping in the following solutions (at 1000 ppm) for 5 minutes: control (distilled water), clove oil, eucalyptus oil, mustard oil, and jojoba oil. Subsequently, the coated fruits with essential oils were preserved in cold room with a temperature of 7±1°C and a relative humidity of 90 – 95 % for a duration of 24 days. The obtained data revealed that immersing in essential oils of winter guava fruits at concentration of 1000 ppm significantly reduced loss in weight of fruit, rot and respiration rate in addition its also improved fruit firmness. SSC%, acidity, SSC/acid ratio and ascorbic acid content compared to control treatment during cold storage. Moreover, the results show a significant reduction in loss of weight, decay, and respiration rate of guava fruits when Eucalyptus and clove oils were utilized. Furthermore, the applications of Eucalyptus and clove oils demonstrated effectiveness in keeping firmness, acidity, vitamin C content, SSC%, and SSC/acid ratio in guava fruits during the storage. In conclusion, Eucalyptus oil and cloves oil proved to be highly effective in reduce weight loss, decay, and respiration rates while concurrently maintaining the overall quality of winter guava fruits under cold storage conditions for a duration of 24 days, in comparison to the other treatments. [ABSTRACT FROM AUTHOR]

The aim of the presented study is to examine the physicochemical parameters of the lipids present in Lupinus mutabilis seed and to compare the results with the available data for other commonly used vegetable oils. The oil quality indexes, oxidative stability index (OSI), and melting characteristics are examined. Andean lupin oil has remarkably high oxidative stability (OSI = 65 h) comparable to high‐oleic oils counterparts. Quality parameters meet commonly accepted standards, including peroxide value (3.95 meq O2 kg−1) and p‐anisidine value (1.25). The acid number value is 1.85 mg KOH g−1. The iodine value is 110.27 g/100 g, while the enthalpy required to increase the temperature of the sample from −60 to 80 °C is equal to 57.41 kJ kg−1. The beginning of the melting event (Tonset) and the phase transition temperature (Tpeak) values for L. mutabilis seed oil are −29.46 and −22.63 °C, respectively. The presented results indicate the unusually high oxidative stability of the oil obtained from L. mutabilis seeds, which opens up a whole spectrum of application possibilities, e.g., designing blends with other commonly used vegetable oils to enhance their low stability. Practical Applications: The presented results provide insight into physicochemical parameters of the lipid fraction isolated from Lupinus mutabilis seeds. Andean lupin oil has very high oxidative stability, comparable to high‐oleic rapeseed and sunflower oils. Therefore, the identified potential use of the studied oils is, e.g. an additive that can increase the stability of commercial vegetable oils characterized by much lower oxidative stability. [ABSTRACT FROM AUTHOR]

The adsorption properties of powdered and composite sorbents in sorption from dilute solutions and in sorption of oils were studied. Acetic acid solutions and such oils as liquid paraffin and MS-20 industrial oil were chosen as examples. The sorbents were based on thermally expanded graphite prepared from hydrolysis lignin using thermal and electrochemical technologies. High adsorption performance of thermally expanded graphite and its ability for regeneration after the sorption from solutions were proved. The influence of the density of the composite sorbents on their ability to adsorb oils was examined. An equation was obtained for calculating the oil absorption coefficient after keeping the composite sorbents in oils for different times, and the constants of this equation, which depend on the sorbent density and kind of oil, were calculated. [ABSTRACT FROM AUTHOR]

Tricarboxylic acids are molecules of interest for the synthesis of highly cross‐linked polymers, for instance, for the curing of epoxy resins. Herein, a synthesis route to a novel high oleic sunflower oil based triacid is described by applying a ruthenium catalyzed oxidative cleavage of its double bonds. A statistical concept is devised for the prediction of the yields of mono‐, di‐, and trifunctional derivatives that can be formed from high oleic sunflower oil, depending on the overall conversion of double bonds into this functional group and the overall oleic acid content of the used oil. This concept proved to be highly useful for the explanation of seemingly moderate triacid yields, which are inherently dependent on the unsaturated fatty acid content of the used oil. All obtained sunflower oil based polyacids are fully analyzed by attenuated total reflection infrared spectroscopy (ATR‐IR), electrospray ionization mass spectrometry (ESI‐MS), 1H, 13C, and quantitative 31P nuclear magnetic resonance (NMR) spectroscopy. In addition, a more sustainable purification procedure is developed to obtain a polymerizable mixture of polyacids containing more than 2.0 carboxylic acids per molecule in average. Practical applications: Tricarboxylic acids are valuable monomers for the synthesis of cross‐linked polymers. The herein reported procedure represents a hitherto unknown synthesis route towards a new triacid and polyacid mixture directly from high oleic sunflower oil. [ABSTRACT FROM AUTHOR]

This study aimed to derive a new composite demulsifier for dehydration of highly emulgated oil with high paraffin content, reducing the emulsion stability. The main active substances are fatty acids of cotton steatite esterified with polyethylene glycol, as well as sulfanol, Sintanol ALM‐10, silica gel, and white spirit in certain proportions. Studies under laboratory conditions on the demulsification of oil from Ashysay field showed that the new composite demulsifier is a suitable reagent for the destruction of water‐oil emulsions. Sulfanol and Sintanol ALM‐10 confer washing and wetting effects on the mixture, and silica gel favors the adsorption of oil asphaltenes onto its surface. [ABSTRACT FROM AUTHOR]

Background: The widespread consumption of trans-fats across the world represents a worrying scenario, as it is directly responsible for coronary heart disease and related mortality. Recognizing its dangers, the WHO has set an agenda to eliminate trans-fats by 2023. In India, the Food Safety And Standards Authority ensures safe and wholesome food consumption. In light of the WHO's standards for the elimination of trans-fats, the FSSAI recently notified limits of trans-fatty acids to not more than 3% in all fats and oils by January 2021 and 2% by January 2022, as well as a limitation on all food products in which edible oils and fats are ingredients to not contain trans-fatty acids of more than 2% mass of total oils/fats in the product by January 2022. Objective: Given the need to eliminate the consumption of trans-fats, it is necessary to assess the implementation of trans-fat regulations in India in order to determine the current status of enforcement and suggest measures for improvement. Methods: Empirical research was conducted through a questionnaire to analyze India's current status and difficulties in enforcing trans-fat regulations. Results: Although all states have included compliance of trans-fat regulation in the agenda of the State Surveillance Plan but are facing some implementation challenges such as lack of lab infrastructure, lack of trained manpower, unsupportive FBOs, insufficient budget, lack of testing kits, and excluding proprietary food from compliance with trans-fat regulations. Further, all states have felt the need to develop a guideline/manual to facilitate enforcement of the trans-fat regulations. In light of this, the article has critically analyzed the legal framework for implementing trans-fat regulations in India to identify specific implementation challenges due to scattered regulations and recommend suggestive measures for developing the guidelines/ manual to facilitate effective implementation of the said regulation. [ABSTRACT FROM AUTHOR]

The composition of the products of thermolysis of the oil residue in isopropyl alcohol at temperatures of 350, 375, 400, 425 and 435°C has been studied. A comparison is made of thermolysis products obtained both in the presence and without the use of isopropyl alcohol. The change in the material composition of the thermolysis products has been established. The gas composition was determined, as well as the redistribution of hydrocarbons in the oil part before and after thermolysis with isopropanol. [ABSTRACT FROM AUTHOR]

The pumpkin (Cucurbita pepo L.), of American origin, represents one of the most used species today. Mexico is an important center of origin, domestication and diversification of the genus Cucurbita. Pumpkin production in Mexico places it in sixth place. This crop has as main limitation for its production the incidence of different harmful organisms, where foliar diseases of fungal origin are the most important, where powdery mildew stands out with economic losses of 50 to 100 %. For proper management, an important element is the correct identification of the causal agent, since two different genera and species are associated with the disease. Worldwide, the identified species that infect the Cucurbitaceae family are Podosphaera fusca (Fr.) Braun &. Shishkoff (syn.: Sphaerotheca fusca (Fr), Podosphaera xanthii (Castagne) U. Braun & Shishkoff) or Golovinomyces cichoracearum (DC.) V.P. Heluta. The control of the pathogen has been carried out mainly with the use of fungicides. However, its use causes negative effects on the biodiversity of agroecosystems, which can cause irreversible damage to the environment, increase production costs and enhance fungus resistance. Hence the importance of seeking new alternatives for its management, such as the use of oils, salts and biological control agents. This paper presents a review related to the updated identification of pumpkin powdery mildew, as well as trends in its management. [ABSTRACT FROM AUTHOR]

The depletion of natural resources, the increasing use of valuable land surface for human activities, and the generation of waste are detrimental to the planet. Sustainable alternatives to guarantee a sufficient supply of food, feed, and biomaterials are needed. Insects may hold an interesting position in a circular economy to tackle contemporary societal challenges. Using insects for food, feed, biomaterial production, and to valorize side‐streams, have gained increased interest. Mealworms are amenable to large‐scale farming. Herein, the potential of mealworm oil for implementation in a cosmetic hand cream is evaluated. It is shown that mealworms are rich in oil (≈30% of the dry weight), and the oil can be extracted using hexane or ethyl acetate as a solvent. The euthanization step of mealworms has profound effect on the free fatty acid content. The fatty acid profile indicates a large proportion of unsaturated fatty acids, which is promising for use in cosmetic applications. In a proof of concept, the mealworm oil is implemented in a hand cream and compared to hand cream containing macadamia nut oil. No differences in odor and aspect/stability are observed, but mealworm creams are slightly less white color. Mealworm oil is suitable for cosmetics applications. Practical applications: Several insect species can be sustainably reared on low‐value organic side‐streams, requiring only small amounts of land‐surface, less water, and producing less greenhouse gases. In addition, they have short life cycles and can be reared continuously and locally. This implies that insects are an interesting source of biological materials including proteins and oils. Insect oils, including oil of mealworms, have interesting fatty acid profiles that make them amenable to replace oils of vegetable origin for applications within cosmetics. The results indicate that mealworm oil can be a novel, sustainable ingredient for use in the cosmetics industry. [ABSTRACT FROM AUTHOR]

Microencapsulation of various substances encompasses a vast field of exceptional application in modern medicine, pharmacy, perfumery and cosmetics, biomedical engineering, as well as in the textile, petroleum and general industries. Although this process can be effected in different ways, depending on its nature (physical, chemical or physicochemical process), physicochemical group of procedures and in particular coacervation is one of the most preferred in terms of ecological purity and biodegradability of the materials used in this method of producing microcapsules. The material in coacervation process used to produce the microcapsules is entirely from natural sources, which would allow their biodegradability over time. The coacervation can be divided into two types: simple and complex. In the microencapsulation of expensive natural products, they need to be diluted with a suitable solvent for three reasons: on the one hand - due to the cost of the encapsulated substance, on the second - to stabilize the core material, and on the third hand - to increase the efficiency of the process, resulting in higher yield and quality of the microcapsules obtained. This article examines the effect of the type of solvent (playing the role of media for diluting the encapsulated substance) on the encapsulation efficiency, yield, and quality of the microcapsules obtained, in the microencapsulation of rose oil using the complex coacervation process. [ABSTRACT FROM AUTHOR]

This paper presents the design, optimization, and calibration of multivariable resonators for microwave dielectric sensors. An optimization technique for the circular complementary split ring resonator (CC-SRR) and square complementary split ring resonator (SC-SRR) is presented to achieve the required transmission response in a precise manner. The optimized resonators are manufactured using a standard photolithographic technique and measured for fabrication tolerance. The fabricated sensor is presented for the high-resolution characterization of dielectric substrates and oil samples. A three-dimensional dielectric container is attached to the sensor and acts as a pool for the sample under test (SUT). In the presented technique, the dielectric substrates and oil samples can interact directly with the electromagnetic (EM) field emitted from the resonator. For the sake of sensor calibration, a relation between the relative permittivity of the dielectric samples and the resonant frequency of the sensor is established in the form of an inverse regression model. Comparisons with state-of-the-art sensors indicate the superiority of the presented design in terms of oil characterization reliability. The significant technical contributions of this work include the employment of the rigorous optimization of geometry parameters of the sensor, leading to its superior performance, and the development and application of the inverse-model-based calibration procedure. [ABSTRACT FROM AUTHOR]

Plant oils have been applied for numerous purposes. Developing the composition of oils through nanotechnology has become a requirement, whether from a medical or industrial point of view. In this study, nanoemulsions (NEs) of olive and peanut oils were evaluated. GC-MS was used to determine the saturated and unsaturated fatty acids contents in both oils. Based on the area %, cis-8,11,14-eicosatrienoic acid (54.0%), myristic acid (30.7%), and arachidonic acid (23.1%) were the greatest constituents in peanut oil, while arachidonic acid (23.2%), cis-11,14,17-eicosatrienoic acid (22.7%), and cis-11-eicosenoic acid (11.4%) were the greatest constituents in olive oil. TEM examination indicated that the diameter of peanut oil NEs (14.6 nm) was less than that of olive oil NEs (24.5 nm). Olive oil and its NEs exhibited more antioxidant activity than peanut oil and its NEs had IC50 values of 158.6, 102.5, 435.1, and 291.5 μg/mL, respectively. Negligible hemolysis was observed using olive oil, unlike peanut oil, while hemolysis based olive oil NEs was increased compared with hemolysis based peanut oil NEs, particularly at high concentrations of 600 to 1000 μg/mL. Molecular docking investigation offered the structure-activity correlation and binding modes of cis-8,11,14-eicosatrienoic acid with Salmonella typhi (5ZXM) enzymes. [ABSTRACT FROM AUTHOR]

The evaluation of the state of transformer oil-immersed insulation based on the traditional methods becomes unreliable due to the nonuniform aging effect. To address this issue, a novel model for accessing the aging information of transformer oil-immersed insulation at the hotspot is proposed. In this article, frequency-domain spectroscopy (FDS) is selected as the carrier for characterizing the aging states of oil-immersed insulation. The multiobjective function for reversing the FDS of the hotspot is constructed based on the dielectric response equivalent circuit. Then, the nondominated sorting genetic algorithm with the multiconstraint scheme is proposed to solve the multiobjective function, by which the FDS data of the transformer hotspot region are acquired. The verification results indicate that the average standard deviation between the computed FDS of the hotspot region and the measured data is less than 0.26. The contribution of this article is in the exploration of the proposed model as a potential tool to extract the FDS data of the hotspot region. This will promote a more reliable aging evaluation of the transformer oil-immersed paper insulation at the hotspot. [ABSTRACT FROM AUTHOR]

From the actual development and testing requirements of horizontal wells in domestic oilfields, according to the problems that the common sensors have relatively low resolution during the water cut measurement for the oil–water flow in the horizontal wells with medium and low production, a trielectrode capacitance sensor (TECS) is designed and a water cut measurement system based on TECS is developed for different conditions of horizontal oil–water flow. Specifically, the electrostatic field distribution of the annular measurement region is investigated under different conditions of horizontal stratified flow. Then, its equivalent capacitance on the electrodes is analyzed. Based on the simulated results, the effects of structural parameters on sensitivity distribution are analyzed, including the electrode length, the radius of the flow channel, and the thickness of the insulation, determining its optimal structure. Moreover, the static and dynamic experiments, as well as the field testing, validate the designed TECS, indicating that the TECS enables measuring the water cut of horizontal oil–water flow, especially under low flow rate and oil–water stratified conditions. The developed TECS could realize the water cut measurement with a wide flow rate range (3–60 m $^3$ /d) and the full water cut range (0%–100%) for the horizontal oil–water flow. [ABSTRACT FROM AUTHOR]

The future demand for electric vehicle (EV) charging power is expected to increase the peak loading of existing distribution transformers. In the absence of appropriate solutions, this may lead to the replacement of transformers with higher-rated types, incurring significant expense. Therefore, a novel approach is proposed to improve the management of transformer EV charging loads, avoiding or postponing the need for a transformer upgrade. It allows for the determination of whether loads that exceed transformer nameplate ratings are acceptable in terms of power level, time and duration. This is achieved with knowledge of the maximum charging duration, transformer thermal time constants, current loading levels, voltage regulation limits, oil pressure and temperature limits, and desired transformer lifetime requirements. The results of a case study are presented based on a future EV car park scenario for which an EV charging load is added to the existing base load on a 300 kVA transformer. The results show the proposed approach has advantages over the traditional approach of limiting loading to nameplate levels. These include reduced waiting time and increased levels of charging power, which are achieved without compromising the desired transformer lifetime target. [ABSTRACT FROM AUTHOR]

Fats, oils and grease (FOGs) deposits in sewers have recently become a significant problem, causing financial strain on water companies, damaging sewer lines, and exposing the environment to dirty water through sanitary sewer overflows. Despite the proactive use of grease traps/interceptors for physical oil-water separation, the issue of FOG deposits persists. This study proposes the use of adsorption-based oil-water separation, employing superhydrophobic cotton, as a new alternative method for removing FOGs. Durable superhydrophobic cotton was successfully prepared using a simple two-step sol-gel method, with octadecyltrimethoxysilane (ODTMS) as a modifying silane. The resulting cotton samples demonstrated remarkable superhydrophobicity, evidenced by water contact angle (WCA) above 154°. Additionally, it exhibited exceptional durability and stability when exposed to hot water, harsh acidic and alkaline solutions, as well as during a laundry test. Moreover, the cotton displayed excellent oil-water separation efficiency (> 98 %) and maintained consistent performance throughout 20 reuse cycles, highlighting its high reusability. This approach holds the potential to address the prevailing FOG deposit issues and contribute to more efficient and sustainable wastewater management practices. [ABSTRACT FROM AUTHOR]

Optimal pump scheduling ensures the safe and economic operation of the oil pipelines, which is also of vital significance for energy conservation as well as carbon emission reduction. This article proposes a framework adapting the data-driven pressure loss estimation with the long short-term memory neural network (LSTM-NN) and pump characteristics fitting with quadratic polynomials to model-based optimal pump scheduling for the multiproduct refined oil transmission system. The data-driven methods are data-adaptive with periodical field data in a rolling-training manner, and thus can reflect actual working conditions in the transmission pipelines. The presented LSTM-NN for pressure loss estimation integrating the characteristics of multiproduct refined oil pipeline transmission has good performance with an acceptable mean squared error of 0.016 MPa2 in real applications. The optimization model makes the time precision down to the minute level, which is more convenient for the system dispatchers to operate the pumps following the optimal schedule. Practical implementation and field test are carried out in a real-world pipeline system, which verifies that the proposed framework is more practical and better-performed than the manual schedule. [ABSTRACT FROM AUTHOR]

In the construction process of intelligent pipeline system, pipeline monitoring is an important content to improve the safety of pipeline operation. Small leak location, in particular, is the primary focus of pipeline monitoring due to the unclear pressure drop point. To solve this, in this article, a data driven-based method of small leak location is proposed. First, through the collected pipeline parameters, empirical flow variables, and historical pressure values in pipeline system, a pipeline model based on pressure along pipeline is presented by a three-layer neural network to close to the industrial scenarios. Then, on the basis of the analyzed propagation process of negative pressure wave, an action-dependent heuristic dynamic programming with pressure–distance physical constraints is proposed to obtain the small leak location result. The proposed method is suitable for the collection of only pressure data scenario, which expands the application range. Finally, different cases of small leak location results indicate that the proposed method can locate the leak point, and the field tests further show that the proposed method has satisfactory performances in pipeline leak analysis. [ABSTRACT FROM AUTHOR]

Spray drying is an efficient, rapid and relatively low-cost method for preparing microencapsulated lactic acid bacteria (LAB) in industry, but high temperature reduces the survival rate of LAB. Oil can polymerise with LAB by hydrophobicity and reduce the thermal and oxidative damage on bacteria during spray drying. However, oil is easily oxidised during spray drying, and its insolubility makes it difficult to evenly disperse the emulsion in the oil phase. In this comprehensive review, the oils used for LAB microcapsule and its protectional mechanism were discussed. And then wall materials and modification methods, which stabilizes co-microcapsule containing lactic acid bacteria and oil, is presented. Oils were a promising material for spray-dried LAB. Liquid oils with more unsaturated fatty acids reduced oxidative stress. Solid oils with high saturated fatty acid content are often added in the form of solid small particles, reducing the bacterial thermal damage by absorbing heat during spray drying. Appropriate wall materials and pre-treatment on oil-LAB co-microcapsule can reduce lipid oxidation, stabilize the emulsion and enhance the survival rate of lactic acid bacteria after spray drying. [Display omitted] • Oil provides a protective barrier to oxygen and heat. • The polysaccharide matrix forms a mesh gel that stabilizes bacteria. • Proteins unfold and reorient at the water-oil interface to stabilize the emulsion. • The survival rate of bacteria could be improved by wall material modification. [ABSTRACT FROM AUTHOR]

Power transformers are critical assets for generation and grid. Controlling their aging is an essential task to ensure the availability of installations, and to optimize maintenance and operational costs over their lifetime. Large power transformers do not always operate at their full cooling capacity, and the cooling efficiency is often adjusted by steps (each different step being also called a “cooling stage”) based on the top-oil, winding temperature indicator or hot-spot temperature. Various dynamic thermal models exist in the literature, but none of them provide easy-to-use correction factors to consider the effect of the cooling stage on the coolers’ thermal resistance as well as on top-oil and hot-spot gradients. The purpose of this article is to propose a simple yet accurate model for the thermal monitoring of Oil Directed Air Forced power transformers. Several applications of the model are given such as cooling efficiency monitoring, evaluation of the load capability (or loadability), and coolers temperature control improvement. [ABSTRACT FROM AUTHOR]

Outdoor oil-filled cable terminations play an important role in power transmission and distribution networks, but their frequent explosions and disintegration accidents in cold environments pose great risks to the stable operation of power systems. In this study, an electric field-temperature multi-physical field simulation model was built based on 220 kV oil-filled cable termination. The dynamic solidification process of the insulating silicone oil was analyzed. It is found that the solidification of silicone oil is a temporal and spatial evolutionary process, which is closely related to the load current and the external environment. The solidification of filled and coated silicone oil will induce air gap defects, which will lead to different electric field distortion at different interfaces, especially at the stress cone/cable insulation interface. So the effects of different states of coated silicone oil on partial discharge at the interface are tested. Compared with the non-coating condition, solidification of coated silicone oil will aggravate partial discharge in cold environments, which is irreversible. The related results indicate the fault mechanism of oil-filled cable terminations subjected to cold environments and provide references for the selection of insulation materials and other measures to improve the reliability of cable terminations considering extreme environments. [ABSTRACT FROM AUTHOR]

Electricity distribution companies are in-charge-of supplying stable electric energy to urban customers over a wide geographical area. In these distribution networks, large number of Distribution-Transformers (DTs) are installed on towers or in electric-rooms with the ratings below 1000 kVA, which are the most important assets of distribution companies. Periodic maintenance and test services are not economically feasible for all in-operation transformers. Hence, estimating the remaining useful life and scheduling the maintenance times of DTs are of great technical and economic importance. An analytical approach is presented in this paper for predicting lifetime of DTs based on degree of polymerization. An appropriate Machine-Learning (ML) algorithm trained by measured data is selected for forecasting driven load according to the ambient temperature and humidity and day-hour schedules. The relation of Hot-Spot-Temperature in IEC60076∼7 is modified based on the measured data for accounting unbalanced-loading. Neutral-current is predicted using a trained ML-model. Another approach is proposed for determining times of oil filtering services aiming to minimize the maintenance cost and maximizing the remaining life. The proposed lifetime estimation method is validated by comparing its results with the damaged DT data of a sample network chosen as the case studies for this research, i.e., Bushehr province, Iran. [ABSTRACT FROM AUTHOR]

In this paper, a reduced computational fluid dynamics (CFD) model is proposed for determining the total heat dissipation and the oil temperature distribution of transformer radiators in oil natural air natural (ONAN) cooling mode. In the reduced radiator CFD model, the air flow simulation is replaced with an optimized air heat transfer coefficient (hair) equation. An experimentally verified full radiator CFD model, which includes the air flow simulation, has been introduced as a benchmark model for evaluating the validity of the reduced model. It was found that one ${{\boldsymbol{h}}_{{\boldsymbol{air}}}}$ can provide sufficient accuracy in simulating the air convection effect of transformer radiators. An ${{\boldsymbol{h}}_{{\boldsymbol{air}}}}$ equation was derived through a parametric study using the full radiator CFD model. The performance of the proposed ${{\boldsymbol{h}}_{{\boldsymbol{air}}}}$ equation was compared with the existing empirical equations, and its validities for different insulating liquids and different ambient temperatures were proven by additional CFD modelling. This ${{\boldsymbol{h}}_{{\boldsymbol{air}}}}$ equation can be transformed into a dimensionless form to help the radiator design and facilitate the complete-cooling-loop (CCL) based transformer CFD modelling. [ABSTRACT FROM AUTHOR]

This papers presents a numerical approach based on computational fluid dynamics (CFD) that was developed to ensure that gravity oil-water separators at Hydro-Québec electrical substations comply with the environmental legislation in place. More precisely, multiphase simulations are performed for two operating conditions of an in service separator, and an experimental setup is used to produce an oil spill and to measure the time-varying oil concentration at the separator outlet. The results show that, for the tested conditions, the oil droplet size at a separator inlet generally follows a log-normal distribution and that the droplet diameter varies between 100 and 1000 µm with a mean value of 475 µm. Furthermore, both the experimental and numerical results show that the time required for the oil droplets to reach the separator outlet is quite shorter than the theoretical mean residence time. Finally, this study demonstrates that the numerical model predicts the separator efficiency within 1% of the measured value, and that it can be a valuable tool to investigate existing separators or to design new ones. [ABSTRACT FROM AUTHOR]

The corrosion of transformers by multiple sulfides seriously affects the safe operation of transformers. However, there is a lack of quantitative characterization of the extent to which temperature and oxygen as well as changes in sulfide species affect the aging of oil–paper insulation. In this study, the aging characteristics of oil–paper insulation systems were analyzed in terms of the moisture in the oil, moisture in the paper, acid value, and furfural in the presence of multiple sulfides, where the temperature and the oxygen concentration are used as independent variables. A strong positive correlation between the acid value and the furfural obtained by means of Spearman’s correlation analysis. The acid value and furfural content in the oil were then analyzed and compared according to a nonparametric test, and it was found that both the oxygen changes and the temperature changes had a relatively obvious effect on the acid value in the oil. The effect of the temperature change on the furfural was greater than the effect of the oxygen change on the furfural. Finally, a multiple linear regression analysis was performed for the change in the acid value of the oil with the change in the oxygen content and temperature to obtain the linear fitting formulas for the effects of the time, temperature, oxygen content percentage, and sulfide groups on the acid value. This study can be used to quantify the magnitude of the influences of the oxygen, temperature sulfide groups, and other factors on the aging characteristic parameters of the oil–paper insulation system and to provide a certain reference for studying the quantitative characterization of the sulfur corrosion degree by using the change in the acid value in oil. [ABSTRACT FROM AUTHOR]

Measuring the furan concentration in transformer oil is one of the most common methods of monitoring and evaluating insulation paper and estimating its degree of polymerization (DP). Here, methods for measuring furan concentration, especially ultraviolet-visible (UV-Vis) spectroscopy method, are reviewed on the old transformers oil. The results show that the excessive turbidity of old oils and noise at low wavelengths are the main disadvantages of this method, which reduce the measurements accuracy. The following solutions are proposed to overcome these disadvantages: 1) diluting insulation oil with hexane to reduce absorption intensity and 2) using average absorption at a given wavelength to reduce noise impact. These solutions are applied to the oil samples of ten old distribution transformer. It is observed that the correlation between 2-furaldehyde (2-FAL) concentration and average absorption intensity in 190–600 nm wavelength range is equal to ${R}^{{2}} =0.98$. A mathematical equation for calculating 2-FAL concentration based on average absorption is presented. It has been shown that to reduce the test time, a 190–400 nm range is the optimal measurement wavelength range. The results show that the average difference between the values of DP in the proposed method and the direct measurement method is equal to 77.5. [ABSTRACT FROM AUTHOR]

The detection of copper particles in transformer oil based on laser-induced breakdown spectroscopy (LIBS) technology has been preliminarily studied, but its limit of detection (LOD) needs to be further strengthened. Therefore, spark-discharge assistant method was used to solve the problem, and its enhancement mechanism has been studied in the research. The study of the correlation between spark-discharge-assisted LIBS (SD-LIBS) spectral intensity and Cu concentration shows that spark discharge has a significant increase in plasma size and spectral intensity; for Cu atomic lines at 324.75 and 327.39 nm, the determination coefficient ${R}^{{2}}$ between their internal standard correction intensity and Cu concentration is promoted to 0.996 and 0.997, respectively; spark-discharge assistant method improves the LOD of LIBS from 0.775 to 0.112 $\mu \text{g}$ /g. Due to the great improvement in detection performance, the application prospect of LIBS as fine particles detection method in transformer oil has become practical. [ABSTRACT FROM AUTHOR]

Although the circulating flow of insulating oil can enhance heat dissipation in converter transformers, it can also influence the space charge distribution in oil–paper composite insulation. In this article, the oil–paper composite insulation between flat electrodes was used as the experimental model. Based on the pulsed electroacoustic (PEA) method, we investigated the effect of uncharged flowing oil on the space charge distribution in composite insulation under a dc electric field and polarity reversal. Under a dc electric field, as the oil flow velocity increased, the amount of interface charge between the oil and paper first increased and then decreased. During the polarity reversal process, the field distortion was aggravated at slower oil flows. These experimental results were explained in terms of the effect of oil flow on ionized charges in the oil. [ABSTRACT FROM AUTHOR]

Thermal aging and ultraviolet (UV) irradiation are used as methods to prepare samples of kraft paper spanning its full lifecycle within a high-voltage transformer, from new to end of life. The mechanical break strain is correlated with the degree of polymerization (DP), representing a progressive deterioration of mechanical properties during aging. Subsequent exposure to oil flow mimicking both normal plant operation and reclamation activities shows that aged paper exposed to high rates of flow experiences noticeable surface roughening. Despite this, no measurable erosion occurs even after long-term temperature/flow cycling in used mineral oil containing a notable particulate content. This indicates that kraft paper is unlikely to be eroded by normal reclamation activities, even in a severely aged asset. This confirms the validity of using this approach to extend plant life. [ABSTRACT FROM AUTHOR]

The lightning impulse breakdown strength of natural ester is lower than that of mineral oil. This article focuses on a discharge mechanism difference analysis of natural ester and mineral oil under a strong impulse electric field (EF). Based on density functional theory (DFT), the ionization energy, electron affinity (EA), and excitation energy of natural ester and mineral oil were calculated under different EF strengths. The microparameters related to the discharge of natural ester and mineral oil were compared, showing that the former has a lower ionization energy and a larger dipole moment. This quality makes natural ester more likely to ionize and produce electrons, which more easily promotes the formation of electron avalanches and streamer. Meanwhile, natural ester molecules are more prone to transition from the ground state to the excited state than mineral oil molecules, exacerbating the photon release and formation of discharges in natural ester. The greater conductivity of natural ester leads to its dispersion and the rapid development of discharge streamers. In addition, an electrostatic potential (ESP) analysis on molecular surfaces was used to predict the active sites of the oil molecular structure. This article provides help for understanding the relationship between the micromolecular structure and the macroscopic discharge characteristics for different types of oil molecules. [ABSTRACT FROM AUTHOR]

Transformer oil and insulation paper are subject to the combined effects of the electric field and temperature operations, which significantly impact insulation deterioration. This article designs a comparative test of the electro-thermal combined aging to obtain several characteristic parameters for the aging degree of oil-pressboard insulation. Molecular dynamics are used to establish a mixed molecular model of oil-pressboard insulation to simulate the pyrolysis reactions at high temperatures using the ReaxFF force field. The microscopic effects of the electric field on the aging of oil-pressboard insulation are studied. The rationale of the simulation model is verified from experimental results, and the trend of the reactants and products in the reaction process was considered to determine the influence mechanism of electric–thermal coupling on oil-pressboard insulation. The experimental results show that thermal stress remains the most important factor toward cracking in insulation paper. The acid value and furfural formation rate in oil increase, and the polymerization degree of the insulation paper decreases rapidly after the combined electric and thermal aging. In addition, the molecular dynamics simulations show that pyrolysis increases the bond energy, promotes repulsion between atoms, and leads to fractured bonds. The addition of the electric field increases the susceptibility of the chemical bonds in cellulose molecules to breakage. The morphology of the cellulose chain then changes, and the diffusion of small molecules intensifies. This study reveals the mechanism of insulation aging under electro-thermal coupling through combined macroscopic testing and molecular dynamics simulations. [ABSTRACT FROM AUTHOR]

In this present work, effort was taken to develop a response surface model based on response surface methodology (RSM) paired with Box–Behnken design (BBD). Investigations were carried out to optimize the transesterification of Pongamia Pinnata oil (PPO) under various process conditions such as time (60–180 min), temperature (60 °C–100 °C), and catalyst (1%–3%). The production of PPO methyl ester (PPOME) by the esterification process is carried out using the PPO and methanol (CH3OH) in a 1:6 molar ratio that is fixed as a constant. Here, the input variables are the process variables (independent) and the output variables are the response variables (dependent). The response variables are the breakdown voltage (BDV), kinematic viscosity (KV), and fire point (FRP). The effect of the process variables on the response variables is modeled using RSM paired BBD. The experimental sequence was designed to find the optimum composition of input parameters and output parameters. The associative effects of the input and output variables were designed as a 2-D contour plot and 3-D response surface plots, and the interactive effects were studied using the plots. After optimization, the optimum conditions of the input variables over the BDV, KV, and FRP were found to be the time of 142.07 min, the temperature of 81.52 °C, and the catalyst of 2.41%. The dielectric properties of PPOME were found to be 61.54 kV, 20.50 cSt, and 281.43 °C, which are in the vicinity of the laboratory experimental results. Those indicate that the treatment of PPO with the optimum quantity of the process variables gives an excellent dielectric response. [ABSTRACT FROM AUTHOR]

Dielectric loss factor is an important index to evaluate the quality of transformer oil, which is very sensitive to the response of polar impurities. As a nondestructive testing technology, ultrasonic can identify polar impurities through attenuation characteristics and then determine dielectric loss. In this article, a novel method for detecting dielectric loss factor of transformer oil based on multifrequency ultrasound and particle swarm optimization-Elman neural network (PSO-ENN) forecasting model was proposed. The analysis of the forecast results and precision shows that the dielectric loss factor can be effectively forecast via this method. The experiment verifies that the ultrasonic effect is nondestructive to transformer oil, which lays a foundation for the development of online monitoring system. [ABSTRACT FROM AUTHOR]

Due to rapid temperature rise and insulation moisture, bubbles can generate in the oil-paper insulation of oil-immersed power transformers, which can reduce the dielectric strength of oil-paper insulation and even bring about the risk of insulation breakdown. In order to accurately evaluate the conditions of bubble formation, the physical process of bubble formation in oil-paper insulation is studied in this article. Considering the effects of water vaporization, gas dissolution in oil, and moisture migration on bubble formation, a bubble formation prediction model is constructed. Based on Henry’s law, the dissolution equilibrium of gas in oil is taken into consideration and the upper boundary of the initial temperature of bubble effect (ITBE) envelope is obtained in this model. Based on the moisture equilibrium in oil-paper insulation, the bubble formation process caused by the emergence and rapid evaporation of free water is analyzed, and then, the lower boundary of the ITBE envelope is obtained in this model. The model results show that the moisture content of the pressboard and the presence of free water have a great impact on ITBE. Specifically, the higher the moisture content, the lower the ITBE value. In addition, with the further increase of moisture content, the upper and lower boundaries of the ITBE envelope gradually tend to be the same. However, once free water is present on the surface of cellulose, ITBE decreases rapidly to below 120 °C. The model built in this article is of great significance to study the temperature limit of the power transformer. Hence the ITBE envelope can provide an important theoretical reference for reducing the risk of bubble formation during power transformer operation. [ABSTRACT FROM AUTHOR]

Moringa oleifera Lam (syn. M. ptreygosperma Gaertn.) leaves are globally acclaimed for their nutritional content and mitigation of malnutrition. In most impoverished rural communities including Limpopo, Mpumalanga and KwaZulu Natal of South Africa, powdered leaves of Moringa oleifera are applied as a nutritional supplement for readily available food such as porridge for malnourished children and even breast-feeding mothers. Widely practiced and admired is also the use of the plant seed in the do-it-yourself purification of water by rural South Africans. This study aimed at identifying the chemical and nutritional marker compounds present in South African Moringa oleifera seed oils using high resolution 1-2-dimension gas chromatography in order to give scientific validation to its uses in cosmetics and particularly in culinary practices. Results obtained from two-dimension tandem mass spectrometry chemical signature revealed over 250 compounds, five times more than those reported from one-dimension gas chromatography. Whereas previous reports from gas chromatography-mass spectrometry analysis reported oleic acid (70–78%) as the major compound from oil samples from other countries, M. oleifera seed oil from South Africa is marked by cis-13-octadeaconic acid with 78.62% and 41.9% as the predominant monounsaturated fatty acid in the hexane and dichloromethane extracts respectively. This was followed by cis-vaccenic acid, an isomer of oleic acid at 51% in the acetone extract, 9-octadecanoic acid-(z)-methyl ester at 39.18%, 21.34% and 10.06% in dichloromethane, hexane and acetone extracts respectively. However, a principal component analysis with R2 = 0.98 of the two-dimension tandem mass spectrometry cum chemometric analysis indicated n-hexadecanoic acid, oleic acid, 9-octadecanoic acid-(z)-methyl ester and cis-vaccenic acid with a probability of 0.96, 0.88, 0.80 and 0.79 respectively as the marker compounds that should be used for the quality control of moringa seed oils from South Africa. This study demonstrates that South African Moringa oleifera oils contain C-18 monounsaturated fatty acids similar to oils from Egypt (76.2%), Thailand (71.6%) and Pakistan (78.5%) just to mention but a few. These fatty acids are sunflower and olive oil type-compounds and therefore place moringa seed oil for consideration as a cooking oil amongst its other uses. [ABSTRACT FROM AUTHOR]

This article aims at developing a multigene symbolic regression model of interfacial tension (IFT) for determining the health index of insulating oil. The oil parameters considered for modeling of IFT are break down voltage, resistivity, acidity, tan delta and water. The unique study undertaken in this article attempts to develop a multigene symbolic regression model for generating and evaluating the relationship between IFT and other oil parameters. Data utilized in this study involves actual oil testing parameters of in-service transformers and reactors of age more than 15 years. A sensitivity analysis has been carried out to investigate the relative contribution of input variables to the model output. The result of sensitivity analysis has further been used to determine the weight of parameters for calculating the health index of insulating oil. Finally, the health index of 400 in-service transformer and reactors are evaluated and analyzed. This research will help in undertaking decisions for the replacement of oil based on health index, thereby increasing the life span of transformer and reactors. The health index so obtained will act as a reference for planning necessary maintenance activities of the equipment and thereby saving unprecedented failure of the oil-filled transformer and reactors. [ABSTRACT FROM AUTHOR]