Use Of Additives Research Articles

Guidance on the assessment of the efficacy of feed additives.

This guidance document is intended to assist the applicant in preparing and presenting an application, as foreseen in Article 7.6 of Regulation (EC) No 1831/2003, for the authorisation of additives for use in animal nutrition. It specifically covers the assessment of the efficacy of feed additives.

Evaluation of Modified Asphalt Binders with Soybean Oil-Based Polymers: Preparation Temperature and Rheological Characterization

To investigate the feasibility of bio-based polymers in the modification of base asphalt binder, two soybean oil-based polymers (PAESO) were synthesized from bio-monomers with different functionalities via free radical polymerization. The characterization of both PAESOs was conducted using Hydrogen nuclear magnetic resonance and Gel Permeation Chromatography analyses, the results showed that the bio-monomer with a higher functionality exhibited a stronger tendency towards self-polymerization, resulting in the polymer with a high conversion rate (44.44 %) and a slightly lower molecular weight (14.76 kDa). The optimal mixing temperature for preparing PAESO-modified asphalt binders was determined through Molecular Dynamics (MD) simulation and Laser Scanning Confocal Microscopy. The MD simulation results indicated that PAESO-modified asphalt models had reached the most stable configurations at a mixing temperature of 160 °C, as evidenced by fewer and more homogeneous distributed small bright spots observed in fluorescence images. This suggested that the outstanding compatibility between PAESO and asphalt binders could be obtained at the optimal mixing temperature of 160 °C. Furthermore, the rheological characteristics of asphalt binders modified with PAESO were examined through Dynamic Shear Rheometer and Bending Beam Rheometer tests. The results revealed that PAESO mainly exhibited a softening effect by significantly enhancing the flexibility, stress relaxation, fatigue, and thermal cracking resistance of the base asphalt binders at intermediate and low temperatures. PAESO-L modified asphalt manifested elastic properties akin to those observed in polymer-modified asphalt within the low-frequency and high-temperature domain. Additionally, PAESO derived from monomers with a higher functionality presented notable benefits in enhancing thermal and fatigue cracking resistance than that of PAESO with a lower functionality. These findings provide valuable insights for the preparation and development of bio-polymer additives for use in asphalt materials.

Repurpose of used frying sunflower oil as an ecofriendly plasticizer for polylactic acid

The development of competitive and sustainable additives for use in semicrystalline polymers is currently an area of growing interest in scientific and engineering areas. However, the feasibility of using waste oils as raw materials to produce effective plasticizers for these polymers has not yet been thoroughly investigated. In this work, the plasticization of polylactic acid (PLA), which is essential to improve its ductility, was studied using different contents of low molecular weight plasticizers: one synthesized from sunflower (Helianthus annuus) oil used in frying (USOP) and the bio-based commercial tributyrin (TB), selected as a control plasticizer. The experimental results revealed changes in the properties of pure PLA matrix that were explained considering the shape and chemical structure of the different plasticizers. Both compounds drastically decreased the glass transition temperature of PLA as well as the elastic modulus and tensile strength, although increase the elongation at break. The greatest plasticizing effect was obtained by adding 15 percent by weight of TB to the biodegradable matrix. However, the synthesized bio-based plasticizer exhibits a desirable low volatility, thus its thermal degradation occurs at higher temperatures in comparison with that of TB. Furthermore, the water vapor permeability of the PLA is not affected when USOP is used as plasticizer, which is a very interesting result for applications in which the material is in contact with food or humid environments.

Cellulolytic and Ethanologenic Evaluation of Heterotermes indicola's Gut-Associated Bacterial Isolates.

Cellulose is the basic component of lignocellulosic biomass (LCB) making it a suitable substrate for bioethanol fermentation. Cellulolytic and ethanologenic bacteria possess cellulases that convert cellulose to glucose, which in turn yields ethanol subsequently. Heterotermes indicola is a subterranean termite that causes destructive damage by consuming wooden structures of infrastructure, LCB products, etc. Prospectively, the study envisioned the screening of cellulolytic and ethanologenic bacteria from the termite gut. Twenty six bacterial strains (H1-H26) based on varied colonial morphologies were isolated. Bacterial cellulolytic activity was tested biochemically. Marked gas production in the form of bubbles (0.1-4 cm) in Durham tubes was observed in H3, H7, H13, H15, H17, H21, and H22. Sugar degradation of all isolates was indicated by pink to maroon color development with the tetrazolium salt. Hallow zones (0.42-11 mm) by Congo red staining was exhibited by all strains except H2, H7, H8, and H19. Among the 26 bacterial isolates, 12 strains were identified as efficient cellulolytic bacteria. CMCase activity and ethanol titer of all isolates varied from 1.30 ± 0.03 (H13) to 1.83 ± 0.01 (H21) umol/mL/min and 2.36 ± 0.01 (H25) to 7.00 ± 0.01 (H21) g/L, respectively. Likewise, isolate H21 exhibited an ethanol yield of 0.40 ± 0.10 g/g with 78.38 ± 2.05% fermentation efficiency. Molecular characterization of four strains, Staphylococcus sp. H13, Acinetobacter baumanni H17, Acinetobacter sp. H21, and Acinetobacter nosocomialis H22, were based on the maximum cellulolytic index and the ethanol yield. H. indicola harbor promising and novel bacteria with a natural cellulolytic tendency for efficient bioconversion of LCB to value-added products. Hence, the selected cellulolytic bacteria can become an excellent addition for use in enzyme purification, composting, and production of biofuel at large.

Effects of surface chemistry on the mechanochemical decomposition of tricresyl phosphate.

The growth of protective tribofilms from lubricant antiwear additives on rubbing surfaces is initiated by mechanochemically promoted dissociation reactions. These processes are not well understood at the molecular scale for many important additives, such as tricresyl phosphate (TCP). One aspect that needs further clarification is the extent to which the surface properties affect the mechanochemical decomposition. Here, we use nonequilibrium molecular dynamics (NEMD) simulations with a reactive force field (ReaxFF) to study the decomposition of TCP molecules confined and pressurised between sliding ferrous surfaces at a range of temperatures. We compare the decomposition of TCP on native iron, iron carbide, and iron oxide surfaces. We show that the decomposition rate of TCP molecules on all the surfaces increases exponentially with temperature and shear stress, implying that this is a stress-augmented thermally activated (SATA) process. The presence of base oil molecules in the NEMD simulations decreases the shear stress, which in turn reduces the rate constant for TCP decomposition. The decomposition is much faster on iron surfaces than iron carbide, and particularly iron oxide. The activation energy, activation volume, and pre-exponential factor from the Bell model are similar on iron and iron carbide surfaces, but significantly differ for iron oxide surfaces. These findings provide new insights into the mechanochemical decomposition of TCP and have important implications for the design of novel lubricant additives for use in high-temperature and high-pressure environments.

EFFECT OF HUMIC FEED ADDITIVE ON METABOLIC PROCESSES AND PRODUCTIVITY OF BEEF CATTLE

The use of made in Kazakhstan organic and mineral feed additives to in-crease the meat productivity of cattle is important for the agro-industrial complex of the Republic. During the study, qualitative and quantitative analysis of raw materials was made. Quality control of the finished feed additive was carried out following the requirements of the State Pharmacopoeia of the Republic of Kazakhstan. The studies were conducted in accordance with the requirements of the Technical Regulations approved by the Decree of the Government of the Republic of Kazakhstan dated April 23, 2008 No. 380, Regulation No. 7-1/625 dated 11/28/2014 and Regulation (EC) No. 1831/2003 of the European Parliament and of the Council of September 22, 2003, on additives for use in animal feeding. Kazakh potassium humate of the Maykubensky deposit is sterile, non-pyrogenic, non-toxic, and harmless, with an average pH of 11.0-1.0, and has a biological effect on laboratory animals (white mice). The effectiveness analysis in the production experiment allowed us to identify the positive effect of feed additives on metabolic processes and increasing meat productivity in bulls. Regardless of age, on the 7th day of taking the feed additive of potassium humate, the calves' coats acquired a noticeable shine and a bright color, and shedding was completed with-in a month. Clinical signs of metabolic disorders and vitamin deficiency, detected in the farm at the time of the experiment in some animals, pass through 20-30 days from the beginning of the application of the feed additive. The optimal scheme for the use of feed additives was tested on the Kazakh meat breed Akbas, and the concentration of humic substances was selected for the maximum mani-festation of the biologically active effect. Animals became mobile and active, their rumination became more active, they grew noticeably, and the average daily weight gain increased by 7.6-8.9%.

Физико-химические свойства мяса цыплят-бройлеров и влияние на них кормовых добавок «Кумелакт-1» и «Ди-лактоцин-Я»

Purpose. Identification of the impact of new feed additives "Kumelact-1" and "Di-lactocin-Ya" on the physicochemical properties of broiler chicken meat. Materials and Methods. The object of research was broiler chickens and exposure to the feed additives Kumelact-1 and Di-lactocin-Ya. Chimic and biochemical compositions of thoracic muscles of broilers, the content of mineralic substances in thoracic muscles, amino acid and fatty acid co-stars of thoracic muscles were determined by conventional methods according to GOST. Results. Studies have shown the positive effect of the additives “Kumelakt-1” and “Di-lactocin-Ya” on the chemical composition of poultry products. A decrease in fat and an increase in protein in meat has been established. Also, the use of these feed additives increases the content of some essential amino acids in the pectoral muscles of broilers, which can have a positive effect on their growth, as well as on the quality of meat. Conclusion. The use of feed additives “Kumelakt-1” and “Di-lactocin-Ya” not only improves the nutritional characteristics of meat, making it richer in protein and less in fat, but also significantly enriches it with amino acids and minerals. This demonstrates the potential of these additives for use in the poultry industry to create higher value and healthier products, which may be key to the development of innovative approaches in poultry farming.

Guidance on the assessment of the safety of feed additives for the users.

This guidance document is intended to assist the applicant in the preparation and the presentation of an application, as foreseen in Article 7.6 of Regulation (EC) No 1831/2003, for the authorisation of additives for use in animal nutrition. It specifically covers the assessment of the safety for the users.

An In-Depth Stability Study of the Essential Oils from Mentha × piperita, Mentha spicata, Origanum vulgare, and Thymus vulgaris: The Impact of Thermal and Storage Conditions

In recent years, there has been a growing scientific interest in essential oils due to their therapeutic and aromatic properties and as potential alternative natural additives for use as preservatives or antibiotics. However, the literature lacks a comprehensive understanding of their stability and how their composition and properties change over time under various conditions. Through this paper, we aim to enhance the existing literature by providing deeper insights into the stability of essential oils and the sustainability of chemical composition in a time-based approach under various conditions. Therefore, four essential oils of the Lamiaceae family (Origanum vulgare, Thymus vulgaris, Mentha spicata, and M. x piperita) were evaluated with respect to their chemical variation influenced by several factors, such as thermal and storage conditions. Three types of containers were utilized to store the essential oils, i.e., glass ampoules, glass tubes, and metallic containers with plastic caps, for up to six months in −20 °C, 4 °C, 23 °C (with or without light exposure), 35 °C, and 45 °C. Samples were routinely analyzed by GC-MS and components were subjected to principal component analysis to ascertain whether the identified constituents may be useful in reflecting the stability of the analyzed samples. The main compounds appeared to be more stable, while the degradation of minor constituents (<1.0%) occurred in all four essential oils despite the storage conditions. Overall, apart from a slight variation in the chemical load, essential oils can be considered stable for various applications, especially those stored under low oxygen availability conditions.

Increasing the Environmental Friendly of Process Fluids Used for Well Drilling

An important aspect of hydrocarbon drilling is the use of drilling fluids that remove cuttings and stabilize the wellbore, providing better filtration. The properties of drilling fluids are essential to the success of any drilling operation. Fluids were originally developed to enable and cost effectively rotary drilling in subterranean formations. In addition, drilling fluids were designed to form a filter cake, which was primarily designed to reduce filtrate loss to the formation, was thin, and retained the drilling fluid in the wellbore. One of the most important functions of drilling fluids is to minimize the amount of drilling fluid filtrate entering a hydrocarbon containing formation, which can cause damage to the formation due to changes in rock wettability, fines migration, mud plugging with solids, and formation water incompatibility. To stabilize these properties, a number of additives are used in drilling fluids to ensure satisfactory rheological and filtration properties of the fluid. However, the commonly used additives are hazardous to the environment: when drilling fluids are disposed of after drilling operations, they, together with drill cuttings and additives, are discharged into water bodies and cause unwanted pollution. Therefore, these additives should be replaced with additives that are environmentally friendly and provide superior performance. In this regard, biodegradable additives are needed for future research. The review article presents an investigation into the role of various biowastes as potential additives for use in water-based drilling fluids. The use of waste-derived nanomaterial was considered, and rheological and filtration studies of water-based drilling fluids were carried out to evaluate the effect of waste additives on the performance of drilling fluids.

Current Status and Trend on the Adoption of Fish Feed Additives for Sustainable Tilapia Aquaculture Production: A Review

During fish feed production, feed additives are regarded as an essential component of the fish diet. The use of feed additives in fish feed is essential for boosting the growth and immunity of cultured fish. The aim of this study was therefore to make a comprehensive review of the Current Status and Trend in the Adoption of these fish feed additives for Sustainable tilapia production. An exploratory research design was used in the study to review and comprehend various peer-reviewed papers published in national and international publications on issues surrounding fish feed additives currently used in tilapia aquaculture production and the current and future prospect of essential fish feed additives in use. Feed additives are ingredients that are added in small quantities to fish diets to enhance nutrients and preserve the feed. Preservatives, binders, feeding stimulants, and food colourants constitute common feed additives. With increased growth in aquaculture, the use of additives must be promoted in order to optimize the production of farmed fish. The aim of feed additives in fish feed is to promote healthier and faster fish growth in cultured fish. As a result, fish diets should incorporate the right quantities of feed additives. The conclusions drawn succinctly suggest that fish feed with no feed additives is comparable to "a vehicle without fuel" and should be regarded as poor feed when fed to fish in a culture system. And the end result will be a poor fish growth rate, less resistance to diseases, and hence low productivity in an aquaculture production system.

Valorization of sea buckthorn seed protein to hydrolysates: Impact on morphological, structural, functional, and antioxidant properties

AbstractBackgroundIncreasing concerns about nutritional deficiency, food security, and sustainability have emphasized work on exploring alternative and sustainable sources of protein. In this study, an initiative to extract and utilize protein concentrates, and hydrolysates from sea buckthorn seed, otherwise a waste material, is undertaken. The effect of hydrolysis using various enzymes namely pepsin (pH 2.0 and 37°C), trypsin (pH 7.0 and 37°C), and protamex (pH 7.0 and 50°C), for different time durations, namely, 30, 60, 90, and 120 min, on the structural and functional properties of sea buckthorn seed protein concentrate (SSPC), was elucidated.ResultsThe emulsifying activity index and solubility of pepsin‐hydrolysed SSPC increased significantly and were higher than those of trypsin and protamex hydrolysed SSPC samples. A Fourier transformation infrared study revealed that the enzyme hydrolysis treatment reduced the peak intensity in amide I, II, and III bands. A significant change was found in the β‐sheet, β‐turn and random coiling of the secondary structure of SSPC protein by enzymatic hydrolysis. The particle size ranged from 295.8 to 440, 388 to 713.6, 399 to 890 nm for pepsin, trypsin, and protamex, respectively. The microstructure of pepsin‐treated samples showed a more porous and loose structure than native, trypsin and protamex. Antioxidant activity increased significantly for all the samples with enzyme treatments carried out for different periods.ConclusionThe results indicate that the protein‐rich hydrolysates could create new opportunities for the development of effective techno‐functional additives for use in a wide range of food formulations.

Influence of dietary supplementation with new Lactobacillus strains on hematology, serum biochemistry, nutritional status, digestibility, enzyme activities, and immunity in dogs.

The use of antibiotics is associated with many side effects, with the development of bacterial resistance being particularly important. It has been found that dogs and their owners host similar resistant bacteria. This contributes to increased concurrent bacterial resistance and a possible trend of increased bacterial resistance in humans. Thus, using probiotics in dogs is an alternative option for preventing and reducing the transmission of bacterial resistance from dogs to humans. Probiotics are characterized by their potential to endure low pH levels and high concentrations of bile acids in the gastrointestinal tract. Lactobacilli are more acid-tolerant and resistant to bile acid, so they are ideal probiotics to be added to the canine diet. According to the previous studies, the benefits of Lactobacillus are a stable nutritional status and greater digestibility, along with improved fecal scores and reduced ammonia in dogs. However, no studies have been conducted with Lactobacillus plantarum CM20-8 (TISTR 2676), Lactobacillus acidophilus Im10 (TISTR 2734), Lactobacillus rhamnosus L12-2 (TISTR 2716), Lactobacillus paracasei KT-5 (TISTR 2688), and Lactobacillus fermentum CM14-8 (TISTR 2720), or their use in combination. Hence, the aim of this study was to examine the possible effects of the aforementioned Lactobacillus on hematological indices, nutritional status, digestibility, enzyme activities, and immunity in dogs. From the results, a new and safe strain of Lactobacillus may emerge for use as a probiotic in the future. In this study, 35 dogs were allocated equally into seven groups: Group 1 received a basal diet (control), while Groups 2-7 received the same diet further supplemented with L. plantarum CM20-8 (TISTR 2676), L. acidophilus Im10 (TISTR 2734), L. rhamnosus L12-2 (TISTR 2716), L. paracasei KT-5 (TISTR 2688), L. fermentum CM14-8 (TISTR 2720), or a mixture of probiotics (L. plantarum, L. acidophilus, L. rhamnosus, L. paracasei, and L. fermentum), respectively. All probiotics were administered at a dose of 109 colony-forming unit/dog for 28 days. Nutritional status, hematology, serum biochemistry, digestibility, enzyme activities, and immunity parameters were assessed. There were no differences among the groups in body weight, feed intake, body condition score, fecal score, and fecal dry matter on the different sampling days. The hematology and serum biochemical analyses showed a difference only in creatinine activity (p < 0.001), with higher values in group L. fermentum CM14-8 (TISTR 2720) and lower values in group L. paracasei KT-5 (TISTR 2688) than in controls. However, all measurements were within the normal laboratory reference ranges. Fecal characteristics (fecal ammonia and fecal pH), fecal digestive enzyme activities, serum immunoglobulin (IgG), and fecal IgA did not differ significantly among the groups (p > 0.05). Lactobacillus plantarum CM20-8 (TISTR 2676), L. acidophilus Im10 (TISTR 2734), L. rhamnosus L12-2 (TISTR 2716), L. paracasei KT-5 (TISTR 2688), and L. fermentum CM14-8 (TISTR 2720), along with their mixture are safe and non-pathogenic additives for use as new probiotic strains of Lactobacillus in dogs. Although the new Lactobacillus strains had no effect on hematology, serum biochemistry, nutritional status, digestive enzyme activities, immunity, body weight, feed intake, or body condition scores in dogs, further studies should investigate the intestinal microbiota and the development of clinical treatments.

In vitro screening of anti-methanogenic additives for use in Australian grazing systems

Despite considerable effort to develop and optimise additives to reduce methane emissions from cattle, little information on additive effectiveness exists for cattle under grazing scenarios. As the majority of Australian cattle production occurs on grazing land it is pertinent to report on the use of additives under simulated conditions. The current study evaluated the addition of nine additives to Rhodes grass hay under in vitro conditions, to estimate their impact on methane (CH4), gas production, and rumen fermentation parameters (volatile fatty acids, rumen pH and in vitro dry matter digestibility [IVDMD]). Citral extract at 0.1% of rumen media decreased all CH4 production parameters, but reduced gas production and digestibility, compared to a 100% hay control. Similarly, Sandalwood essential oil decreased CH4 production at 48 h, IVDMD and gas production, compared to the control. Biochar + nitrates at 5 and 8% DM, and Biochar + Asparagopsis at 5% DM decreased cumulative CH4 production (15.6%, 25.9%, 23.8%, respectively; P &amp;lt; 0.01), compared to the control. No changes in IVDMD and gas production were observed. As such, the biochar additives were considered the most promising additives from those evaluated with a substrate designed to replicate Australian grazing systems.

Production technology of soy protein additives for use in meat products

Nowadays, the average person's diet does not contain enough foods that are high in readily absorbed proteins. Using cheaper and healthier vegetable proteins in favor of animal proteins is one option to address this issue. The only crop with high-quality protein is soy. With the exception of methionine and cysteine, soy protein has a good balance of all the necessary amino acids. 15–25% of proteins are found in meat products. There are no other vegetable legumes (beans, peas) with a protein content (44–45%) and oil (20–22%) as high as vegetable soybeans while they are in the green bean phase. This crop is particularly nutrient-dense, and adding vegetable soy to diet enables to add proteins and other essential elements to cuisine. As soy protein is more similar to proteins of animal origin in terms of protein complexity and the presence of key amino acids (lysine, tryptophan, etc.), both animal and human organisms require less energy to transform soy protein into body proteins. The use of soy protein additives in meat products leads to enrichment with proteins and a significant improvement in the functional and technological properties that determine the structural and mechanical characteristics of the combined meat products.

An overview on liquisolid technique: its development and applications.

With its simplicity and cost-effectiveness, the liquisolid technique offers solutions for numerous formulation problems. Among these are dissolution enhancement and sustaining drug release, and the liquisolid technique dealt with both approaches. This review focuses on the latest advances in the technique. It discusses modified additives for use as carrier materials, which secure the required large surface area for enclosing liquids. The review also covers the modern liquipellet technique derived from the extrusion/palletization technique. Also, the liquiground term is introduced, combining the advantages of co-grinding with the liquisolid concept. Furthermore, several grades of Eudragits, and hydrophilic retarding polymers are mentioned to explain modes of sustaining drug release. This review sums up the liquisolid technique development and its applications recently achieved.

USE OF THE PAIR COMPARISON METHOD FOR ASSESSING THE QUALITY OF ICE CREAM

The authors chose five samples of ice cream from different brands of domestic producers as objects of study. The authors used a paired method for determining desirability during testing, which is used to identify qualitative differences and the desirability of goods of the same name by the requirements of SS R (State Standard R) 53161-2008. The authors also carried out an organoleptic assessment according to SS R ISO (International Organization for Standardization) 22935-2-2011 Milk and dairy products and organoleptic analysis of paragraph 14, SS 31457-2021 Milk ice cream, cream, and ice cream. The results of the evaluation of ice cream samples by the method of pairwise comparison are also presented. The authors identified evaluation criteria that reflect the consumer properties and attractiveness of the product: packaging, labeling, and organoleptic indicators. The authors have identified evaluation criteria that reflect the consumer properties and attractiveness of the product: packaging, labeling, and organoleptic indicators. Differences in the samples were established. A comparative analysis of the composition showed that one of the samples contains annatto dye, which is not included in the list of food additives for use in the manufacture of ice cream. As a result of testing, the authors identified the most desirable sample. The obtained data can be considered reproducible, taking into account the error probability of 0.01%. The results have practical implications for manufacturers in developing new product lines to meet customer requirements, and for consumers in choosing a competitive product from a variety of product ranges that differ in price and quality.

Systemic measures on reduction of greenhouse gas emissions in animal husbandry enterprises. A review

The paper presents a review of different approaches to solving problems arising upon greenhouse gas emission from activities of animal husbandry enterprises. The sector of ruminant animal production is under close attention for ecological reasons due to its significant contribution to emission of enteric methane (CH4) and an effect on global climate change. Moreover, analysis of the main sources of methane emission in the agricultural sector of the agro-industrial complex, including by species of livestock and poultry, is given. An impact of a feeding system, feeds and feed additives in use and manure storage on nitrogen losses is estimated. In this connection, the authors examine several promising scientific and practical development results that are aimed to reducing emissions and formulating a strategy for controlling direct emissions of greenhouse gases in animal husbandry that do not jeopardize animal productivity, especially in the context of sustainability. Practical activities that envisage the development of the complex of measures for reduction of greenhouse gas emissions are examined. Potential strategies for mitigating their consequences were divided into the following main categories: animal raising, changes in animal diets and manipulations with rumen. Furthermore, several other measures facilitating an increase in livestock productivity and reduction of the negative effect on the environment were taken. Eco-economic methods for assessing emissions of harmful gases in production of animal husbandry products are considered and the necessity of developing simpler cost-effective technologies for quantitative assessment of greenhouse gas emissions and a search for solutions to preserve favorable climate is emphasized. When assessing greenhouse gas emissions, the loss sizes and cumulative ecological damage are taken into account. Realization of strategies for emission reduction should lead to an increase in animal productivity and a decrease in the negative effect of animal husbandry on the environment.

Rational Screening of High-Voltage Electrolytes and Additives for Use in LiNi0.5Mn1.5O4-Based Li-Ion Batteries.

In the present work, we focus onthe experimental screening of selected electrolytes, which have been reported earlier in different works, as a good choice for high-voltage Li-ion batteries. Twenty-four solutions were studied by means of their high-voltage stability in lithium half-cells with idle electrode (C+PVDF) and the LiNi0.5Mn1.5O4-based composite as a positive electrode. Some of the solutions were based on the standard 1 M LiPF6 in EC:DMC:DEC = 1:1:1 with/without additives, such as fluoroethylene carbonate, lithium bis(oxalate) borate and lithium difluoro(oxalate)borate. More concentrated solutions of LiPF6 in EC:DMC:DEC = 1:1:1 were also studied. In addition, the solutions of LiBF4 and LiPF6 in various solvents, such as sulfolane, adiponitrile and tris(trimethylsilyl) phosphate, atdifferent concentrations were investigated. A complex study, including cyclic voltammetry, galvanostatic cycling, impedance spectroscopy and ex situ PXRD and EDX, was applied for the first time to such a wide range of electrolytesto provide an objective assessment of the stability of the systems under study. We observed a better anodic stability, including a slower capacity fading during the cycling and lower charge transfer resistance, for the concentrated electrolytes and sulfolane-based solutions. Among the studied electrolytes, the concentrated LiPF6 in EC:DEC:DMC = 1:1:1 performed the best, since it provided both low SEI resistance and stability of the LiNi0.5Mn1.5O4 cathode material.

Analysis of thermal stability and characterization of paraffin-blended hybrid fuels

PurposeThe purpose of this study is to investigate the physical, chemical and thermal characteristics of paraffin-blended fuels to determine their suitability as fuel in hybrid rockets.Design/methodology/approachWax fuels are viable and efficient alternatives to conventional rocket fuels, having excellent structural strength and thermal and mechanical properties. The authors report a study of the morphological, chemical and thermal properties of paraffin wax with and without additives for use as fuels in hybrid rockets. Scanning electron microscopy, X-ray diffraction and Fourier transform infrared spectroscopy were used for the morphological and chemical characterizations of the fuel blends. The thermal stability and combustion characteristics were assessed under an atmosphere of nitrogen by the simultaneous application of thermogravimetry and differential scanning calorimetry techniques.FindingsThe melting temperatures for pure paraffin and other formulations were around 61°C as seen in differential scanning calorimetry experiments. Variations in the compositions of monoesters, n-alkanes, fatty acids, carboxylic acids methyl and hydroxyl esters in the fuel samples were assessed using Fourier transform infrared spectroscopy. The assessment criterion was chosen as the relative content of carbonyl groups, and the ratio of the stretching vibration of the C–C bonds to the deformation vibration of the aliphatic carbon–hydrogen bonds was taken as the basis for the quantitative calibration. The crystal phases identified by X-ray diffraction were used to identify nonlinear chemicals and alkane lengths. Scanning electron microscopy validated homogeneity in the paraffin-blended samples.Originality/valueThis study presents the thermal stability and other relevant characteristics of fuel formulations comprising unconventional blends.