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This research explores the thermal ageing influence on the Low Density Polyethylene (LDPE) dielectric properties, which is utilised as electrical insulation in high-voltage cables. An accelerated thermal ageing test was done at four temperature ranges ranging from 25 °C to 120 °C to define the degree of material deterioration under thermal ageing and to prevent its failure. LDPE composite samples were made by adding aluminium oxide (Al2O3) inorganic filler in two different grain sizes (nano and micro) with various concentrations. The effect of adding inorganic filler on the acceleration of the thermal ageing of the polymer was studied by heating the samples for different periods of time and measuring the dielectric strength of the samples. The obtained results show that thermal ageing considerably affects the electrical properties of the material. The LDPE/Al2O3 nanofiller sample has the highest dielectric strength value at different temperatures. Thermogravimetric analysis was used to investigate the thermal characteristics of materials. The mechanical characteristics of LDPE polymer are studied using tensile strength and elongation at break tests. References 27, table 4, figures 6.

Due to the colloidal stability, the high compressibility and the high hydration of extracellular polymeric substances (EPS), it is difficult to efficiently dehydrate sludge. In order to enhance sludge dewatering, the process of ultrasonic (US) cracking, chitosan (CTS) re-flocculation and sludge-based biochar (SBB) skeleton adsorption of water-holding substances to regulate sludge dewaterability was proposed. Based on the response surface method, the prediction model of the specific resistance to filtration (SRF) and sludge cake moisture content (MC) was established. The US cracking time and the dosage of CTS and SBB were optimized. The results showed that the optimal parameters of the three were 5.08 s, 10.1 mg/g dry solids (DS) and 0.477 g/g DS, respectively. Meantime, the SRF and MC were 5.4125 × 1011 m/kg and 76.8123%, which significantly improved the sludge dewaterability. According to the variance analysis, it is found that the fitting degree of SRF and MC model is good, which also confirms that there is significant interaction and synergy between US, CTS and SBB, and the contribution of CTS and SBB is greater. Moreover, the process significantly improves the sludge's calorific value and makes its combustion more durable. HIGHLIGHTS Ultrasonic (US) cracking, chitosan (CTS) flocculation and sludge-based biochar (SBB) adsorption of water-holding substances synergistically enhance sludge dewaterability.; Response surface methodology (RSM) was used to optimize the US time and the dosage of CTS and SBB.; Established predictive models for the specific resistance to filtration and sludge cake moisture content.;

The thermal decomposition modeling of starch granules (rice, maize, and potato) is investigated in this work. Thermogravimetric analysis (TGA) under nitrogen conditions and different heating rates is carried out. First, a model‐free analysis is carried out to determine the variability of the activation energy with the relative conversion. The results reveal that the sequence of activation energy is rice > maize > potato. In turn, the activation energy is positively correlated (ρ  =  0.98) with the relative crystallinity determined by X‐ray diffraction (XRD) analysis. Then, a fractional‐order version of the Sestak–Berggren equation is used to model the starch thermal decomposition. A least‐squares approach is used to estimate the underlying parameters by fitting non‐isothermal TGA curves. The results show that the parameters depend on the heating rate, but more strongly on the XRD relative crystallinity. Overall, the results reported in this study indicate that fractional‐order kinetics models provide an accurate description of the starch thermal degradation, without the use of the traditional TGA heuristic methods used for parameter estimation. [ABSTRACT FROM AUTHOR]

This work is devoted to magnesium oxide (MgO) nanoparticles (NPs) for their use as additives for bone implants. Extracts from four different widely used plants, including Aloe vera, Echeveria elegans, Sansevieria trifasciata, and Sedum morganianum, were evaluated for their ability to facilitate the "green synthesis" of MgO nanoparticles. The thermal stability and decomposition behavior of the MgONPs were analyzed by thermogravimetric analysis (TGA). Structure characterization was performed by X-ray diffraction (XRD), energy dispersive X-ray spectroscopy (EDS), ultraviolet-visible spectroscopy (UV-Vis), dynamic light scattering (DLS), and Raman scattering spectroscopy (RS). Morphology was studied by scanning electron microscopy (SEM). The photocatalytic activity of MgO nanoparticles was investigated based on the degradation of methyl orange (MeO) using UV-Vis spectroscopy. Surface-enhanced Raman scattering spectroscopy (SERS) was used to monitor the adsorption of L-phenylalanine (L-Phe) on the surface of MgONPs. The calculated enhancement factor (EF) is up to 102 orders of magnitude for MgO. This is the first work showing the SERS spectra of a chemical compound immobilized on the surface of MgO nanoparticles. [ABSTRACT FROM AUTHOR]

In the restoration or rehabilitation of traditional buildings, compatible materials with known characteristics must be used. However, the existing literature lacks comprehensive studies on the characterisation of Persian mud–straw plaster, focusing primarily on Persian adobe. Moreover, previous research on Persian adobe has primarily employed XRF and XRD tests, neglecting ion chromatography, moisture sorption isotherm determination, and thermogravimetric analysis with differential scanning calorimetry. Consequently, there is a shortage of information regarding the elemental composition, mineralogical characteristics, moisture sorption behaviour, and thermal properties of Persian mud–straw plaster, as well as Persian adobe bricks. This paper aims to address this research gap by examining historical and new adobe bricks and mud–straw plaster used in Iran, utilising a comprehensive array of analytical techniques. The results from XRF analysis reveal relatively similar chemical compositions across all samples, while XRD analysis indicates predominantly similar mineral phases. Ion chromatography results demonstrate higher conductivity and chloride concentrations in the mud–straw samples than the adobe samples, with higher values for new samples than historical ones. Freshly used straw, clay, or soil may have higher chloride concentrations caused by the arid climate and soil salinisation in the area. Additionally, moisture sorption isotherm determination results show that adobe and mud–straw plaster with a higher salt load of chlorides have significantly higher moisture absorption. The increased straw quantity in the samples increases the moisture content. Furthermore, thermogravimetric analysis and differential scanning calorimetry indicate that, at low heating, adobe and mud–straw plaster lose water due to dehydration, and at high heating, they lose carbon dioxide due to decarboxylation. The comprehensive characterisation of Persian adobe and mud–straw plaster in this study fills a significant gap in the literature and offers invaluable insights for informing restoration and rehabilitation processes, ensuring the compatibility of the materials used. [ABSTRACT FROM AUTHOR]

We report the analysis, by the advanced isoconversional method of Vyazovkin, of the thermal events of pyridine molecule loss and spin crossover occurring in the two-dimensional compounds of molecular formulas: Fe(Pyridine)2[Fe(CN)5NO] and Fe(Pyridine)2[Ni(CN)4]. Experimental thermogravimetric data were used to analyze the thermal evolution of pyridine molecules in both compounds. Calorimetry was used to study the spin crossover in Fe(Pyridine)2[Ni(CN)4], while SQUID magnetometric for Fe(Pyridine)2[Fe(CN)5NO]. The analysis of the effective activation energy of the pyridine loss process suggested that, in both compounds, the thermal evolution of these molecules is highly influenced by the particle size due to the occurrence of a structural transformation of the gate-opening type. The effective activation energy of the latter technique applied to compound Fe(Pyridine)2[Ni(CN)4] showed a behavior very similar to that expected for a solid–solid transition that occurs by the nucleation mechanism. The results obtained shed light on the way towards the application of the studied compounds in sensors and switches devises for molecular detection. [ABSTRACT FROM AUTHOR]

The periodic sinc function interpolation offers a compelling solution to address the issue of noise in the analysis of thermogravimetric analysis (TGA) data, thereby enhancing the outcomes of differential techniques such as the Friedman isoconversional method. In this study, we introduce a novel approach that leverages the periodic sinc function interpolation to directly obtain smooth reaction rates from TGA data, eliminating the reliance on numerical differentiation methods. The efficacy of this method has been confirmed through its application to noisy experimental data derived from the thermal decomposition of various polymers, showcasing its robustness. Readers are provided with the corresponding code for Gnu Octave, serving as a free alternative to MATLAB. Additionally, the activation energies calculated from the experimental data using both the Friedman method and periodic sinc function interpolation closely align with those determined by the integral Vyazovkin method, emphasizing the validity and reliability of this new approach. [ABSTRACT FROM AUTHOR]

We report new nanocomposites with poly(benzoxazine-co-epoxy) matrix reinforced with 1 wt% graphene. Curabox 24-111, a benzoxazine resin was copolymerised with Epilok 60-566, a mixture of epoxy resins. Copolymerisation was also carried out in the presence of different graphene powders, namely, Nanene-001 and Nanene-002, used as single fillers and as mixture (relative weight ratio 70:30 or 30:70). DSC results showed the addition of either single filler caused a delay in polymerisation and an increase in the exothermic peak temperature of the curing reaction with a related reduction in ΔH Total. compared to the neat copolymer. Copolymerisation showed a 38% reduction and 24% increase in tensile modulus (E) compared to the neat polybenzoxazine and epoxy polymer, with a respective 18% and 30% reduction in tensile strength (TS). Nanocomposites with 0.7wt% Nanene-002 + 0.3 wt% Nanene-001 showed the highest increase of 35% in TS, a 1.6% reduction in E and 36% increase in elongation at break (EB) compared to the neat copolymer matrix. Samples with 1 wt% Nanene-001 showed the largest reduction of 21% in E, a 27% increase in TS and a 45% increase in EB. Additionally, TGA thermographs showed a 22°C increase in the onset of degradation (300°C–322°C) improving the materials thermal stability. [ABSTRACT FROM AUTHOR]

The thermal decomposition process of 3D printed filament made from micro-nano rice husk (MNRH)/polylactic acid (PLA) blends was studied by dynamic thermogravimetric analysis. The characteristic temperatures and apparent activation energies of unmodified, single modified, and double modified RH/PLA composites were calculated by Friedman (FD), Flynn-Wall-Ozawa (FWO), Coats-Redfern (CR), and Kissinger (KS) kinetic models. With the modification of MNRH and PLA in the composites, the initial thermal decomposition temperature of the composite increased from 236.3°C to 244°C. At the same time, the thermal degradation degree decreased and the transition temperature interval increased. The apparent activation energy (AAE) values of different modified composites ranged from 90 to 120 kJ/mol, depending on the modification method and calculation method of the material. These four kinetic models provide methods to analyze the thermal stability of composites. It is helpful to known the thermal decomposition behavior of MNRH/PLA composites, and it will contribute to the development of MNRH/PLA filament for 3D printing in the application of automotive interior parts production. [ABSTRACT FROM AUTHOR]

While traditional woven textiles have been the subject of many forensic investigations, non-woven fabrics have received minimal attention thus far. Given the expansion of commercial applications of non-woven fabrics, a preliminary investigation of household wipes has been carried out to characterize the compositions of these widely available non-woven fabrics. Infrared spectroscopy and thermogravimetric analysis were employed to identify the fibre type and additives of three types of commercial wipes. Polyester and/or viscose fibres were found to be the main components and, along with the identification of binders, enable source types to be differentiated. The predicted different sensitivities of the fibre types to biodeterioration highlights the importance of future environmental studies for the correct characterization of non-woven fabrics in evidence. [ABSTRACT FROM AUTHOR]

The construction industry must adopt a sustainable and environmentally friendly approach because it heavily relies on natural resources. To tackle this issue, the utilization of industrial by-products such as fly ash (FA), ground granulated blast furnace slag (GGBS), and recycled aggregates (RAs) from building demolition waste has emerged as a significant sustainable element in the production of recycled aggregate geopolymer concretes (RAGPCs). This study evaluated the durability performance and life-cycle assessment (LCA) of FA-GGBS–based RAGPC adhering to German specifications to optimize aggregate particle packing. Six different mixes of RAGPC were developed with various alkaline-activator content (AAC)/binder (B) ratios, ranging from 0.3 to 0.8. The concrete was cast and then ambient cured until testing. Various tests were carried out to evaluate the performance of RAGPC. The tests included compressive strength, durability, water absorption, and volume of permeable pores. The durability was measured using water sorptivity and water permeability tests. In addition, microstructure characteristics, embodied energy, and global warming potential as part of LCA also were evaluated. It was found that ambient-cured geopolymer concretes demonstrated good strength gain, normal pore structure characteristics, and good durability. Strengths ranging from 30 to 64 MPa can be developed with RA and geopolymer binders. The durability of the RAGPC gel and its capillary porosity resulted in water absorption of less than 10%. The water permeability results indicated reduced penetration. In terms of LCA, the RAGPC had an embodied energy of 4.48% and a global warming potential of 0.083, both of which are significantly lower than those of conventional concrete. [ABSTRACT FROM AUTHOR]

Background: Drug release from controlled release delivery systems is influenced by various factors, including the polymer's grade and the drug's hydration form. This study aimed to investigate the impact of these factors on the controlled release of theophylline (THN). This research compares the monohydrate form found in branded products with the anhydrous form in generic equivalents, each formulated with different polymer grades. Methods: Quality control assessment was conducted alongside in vitro evaluation, complemented by various analytical techniques such as X-ray diffraction (XRD) and scanning electron microscopy (SEM). Additionally, thermal analyses using differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA) were employed. Results: Quality control assessments demonstrated that the generic tablets exhibited lower average weight and resistance force compared to the branded ones. In vitro tests revealed that generic tablets released contents within 120 min, compared to 720 min for the branded counterpart. Characterization using XRD and SEM identified disparities in crystallinity and particle distribution between the three samples. Additionally, the thermal analysis indicated consistent endothermic peaks across all samples, albeit with minor variations in heat flow and decomposition temperatures between the two products. Conclusions: This study demonstrated that variations in polymer grade and hydration form significantly impact THN release. [ABSTRACT FROM AUTHOR]

Background: Theophylline (THN), a bronchodilator with potential applications in emerging conditions like COVID-19, requires a controlled-release delivery system due to its narrow therapeutic range and short half-life. This need is particularly crucial as some existing formulations demonstrate impaired functionality. This study aims to develop a new 12-h controlled-release matrix system (CRMS) in the form of a capsule to optimize dosing intervals. Methods: CRMSs were developed using varying proportions of poloxamer 407 (P-407), stearyl alcohol (STA), and hydroxypropyl methylcellulose (HPMC) through the fusion technique. Their in vitro dissolution profiles were then compared with an FDA-approved THN drug across different pH media. The candidate formulation underwent characterization using X-ray diffraction, scanning electron microscopy, Fourier transform infrared spectroscopy, differential scanning calorimetry, and thermogravimetric analysis. Additionally, a comprehensive stability study was conducted. Results: In vitro studies showed that adjusting the concentrations of excipients effectively controlled drug release. Notably, the CRMS formulation 15 (CRMS-F15), which was composed of 30% P-407, 30% STA, and 10% HPMC, closely matched the 12 h controlled-release profile of an FDA-approved drug across various pH media. Characterization techniques verified the successful dispersion of the drug within the matrix. Furthermore, CRMS-F15 maintained a consistent controlled drug release and demonstrated stability under a range of storage conditions. Conclusions: The newly developed CRMS-F15 achieved a 12 h controlled release, comparable to its FDA-approved counterpart. [ABSTRACT FROM AUTHOR]

Magnesiohornblende dehydration was studied using both high-temperature thermogravimetric analysis and high-pressure diferential thermal analysis (HP-DTA). The high-temperature thermogravimetric analysis results revealed that magnesiohornblende dehydration at high temperatures could be divided into three steps: 848–1058, 1058–1243, and 1243–1473 K, and each step followed an n-order reaction (Fn). The dehydration process is characterized by an oxidation-dehydrogenation mechanism, and the dehydration of the last step can be explained as the direct decomposition of the hydroxyl groups connected to the magnesium ions. The HP-DTA of magnesiohornblende dehydration under pressures of 0.5, 1.0, 2.0, and 3.0 GPa revealed the occurrence of two endothermic peaks, indicating that the dehydration occurs in two steps at high temperature and pressure. Our experimental results reveal that during subduction, the fluid released during the dehydration of magnesiohornblende may trigger earthquakes and cause high electrical conductivity anomalies in the subduction zones. [ABSTRACT FROM AUTHOR]

Objective: Alkali-extracted polysaccharides from Abalone viscera (Aavp) were isolated and purified. The structure and antioxidant activity of Aavp were studied, which would provide a reference for developing and applying polysaccharides. Methods: The crude alkali-extracted polysaccharide was prepared by hot alkali extraction and alcohol precipitation. After the purification of DEAE sepharose fast flow and sephacryl S-400 HR, the purified polysaccharide was obtained and subjected to the structural analysis and antioxidant activity assay, such as Gas chromatography (GC), high-performance liquid chromatography (HPLC), infrared spectroscopy (IR), and thermogravimetric analyzer (TGA), etc. Result: Four kinds of components (Aavp Ia, Aavp Ib, Aavp IIa, and Aavp IIb) were obtained from the crude polysaccharide. Because of the highest yield, Aavp IIa was selected for further structural analysis. Aavp IIa was composed of xylose and galactose, with a relative molecular weight of 166513 Da. IR characterized the α-glycosidic bond configuration. The composition of Aavp IIa was possible as follows: The molar percentage of the galactose 1→4 glycosidic bond was 11.81%, the galactose 1→3 glycosidic bond was 34.14%, and the galactose 1→2 glycosidic bond was 10.14%. The molar percentage of the xylose 1→3 glycosidic bond was 33.85%, and the 1→2 and 1→4 glycosidic bond was 10.06%. Thermogravimetric analysis showed that Aavp IIa was broken and decomposed at 226.4~332.6 °C, and the thermal weight loss rate was 43.65%. Antioxidant experiments showed that Aavp IIa had a scavenging rate of 85.89% for superoxide anion radicals and 62.17% for DPPH radicals, respectively, presenting a certain antioxidant activity. Conclusion: Aavp is a heteropolysaccharide with specific antioxidant activity.

Abstract Solid fossil fuels still support the development of the energy and chemical industry. The clean and efficient utilization of solid fossil fuels can effectively alleviate the problems of energy shortage and environmental pollution. An in‐depth understanding of the kinetic process, models, and mechanism of pyrolysis of solid fossil fuels is also of great significance for the exploration and utilization technologies of petroleum resources. Thermogravimetric analysis is an effective method to study the pyrolysis process and kinetics with the advantages of high sensitivity, repeatability, and reliability for data acquisition. Researchers have conducted a lot of research on the thermogravimetric kinetics of solid fossil fuels in recent years, but there is a lack of systematic summary and comparison of kinetic methods, research progress, and trends. Therefore, a comprehensive study on pyrolysis kinetic principles, methods, and models of solid fossil fuels by thermogravimetric analysis is carried out in this paper. The influencing factors of pyrolysis kinetics of solid fossil fuels using thermogravimetry are elaborated and discussed in detail. This study also provides progress in recent years and prospects of thermogravimetric kinetics of solid fossil fuels. It is expected that this paper can provide certain technical support and theoretical guidance for the research on pyrolysis kinetics based on thermogravimetric analysis, and the exploration and development, clean, and efficient utilization of solid fossil fuels.

Thermogravimetric and kinetic analysis of biomass and plastic co-pyrolysis can provide valuable inputs for a better understanding of decomposition mechanisms. Such inputs are important for selecting the appropriate process conditions but can also be helpful for process modelling. This work investigates the properties of heterogenous sawdust in a mixture with polypropylene and polystyrene. Thermogravimetric analysis is conducted to determine the decomposition mechanism and kinetic parameters of investigated mixtures and to derive appropriate conclusions regarding their further utilization potential. Co-pyrolysis was performed on mixtures with the following biomass/plastic ratios: 75-25%, 50-50%, 25-75%, over a temperature range of 30-550 °C, at four heating rates 5, 10, 20, and 30 °C/min, with pure argon as a carrier gas. Obtained results were then subjected to comprehensive kinetic and thermodynamic analysis. The primary goal was to determine effective activation energies using model-free methods, pre-exponential factors, and elementary thermodynamic parameters such as changes in enthalpy, entropy, and free Gibbs energy. Finally, the influence of the heating rate and mixture composition was extensively investigated by analyzing calculated parameters.

Thermal analysis methods, primarily thermogravimetric analysis (TGA), play an important role in the study of phase transitions and degradation of active food components and auxiliary substances during heating or cooling. The most important areas of application of TGA in the food industry include the analysis of patterns of changes in the mass of the studied system during its heating or cooling due to the presence of phase transitions of the first kind and chemical reactions. In this work, a study of the change in mass of biscuit products during heating was carried out. The effect of replacing wheat flour with cricket flour in the amount of 5.0% on the structure of the resulting biscuit product compared to the control was determined. This study showed a change in the distribution of forms of connection of system water with dry substances of the system and, as a result, an expansion of the range of temperatures at which water evaporation from this sample took place. However, with a further increase in the amount of cricket flour in the recipe, which has an increased protein content, an increase in the part of the system water associated with the proteins of this raw material was observed. As a result, the range of temperatures at which water evaporation occurred from biscuit products with cricket flour in the amount of 10.0% and 15.0% decreased. It was noted in the work that the most acceptable functional and technological property of biscuit products is a wider range of forms of connection of system water with dry substances of such food products, since the presence of different forms of connection of water significantly determines the organoleptic indicators of finished products, terms and conditions its storage. The results obtained by the method of thermogravimetric analysis showed that, from the point of view of expanding the spectrum of forms of connection of system water with dry substances of the studied samples, the sample with the replacement of wheat flour with flour from crickets in the3 amount of 5.0% should be considered more acceptable.

This study investigates the intricate thermal decomposition behavior and combustion characteristics of two distinct types of wheat straw pellets (WSP) represented as T1 (100 % wheat straw) and T5 (70 % wheat straw; 10 % sawdust, 10 % biochar; 10 % bentonite clay). Through a thermogravimetric analyzer (TGA) the pellets undergo combustion under varying heating rates (5, 10, and 20 °C/min) in an air atmosphere, ranging from 25 to 1200 °C. Differential thermogravimetric and thermogravimetric analyses reveal four distinct stages of decomposition in the biomass components. The results indicate that the optimal combustion heating rate is 20 °C/min, resulting in the highest reaction rate (∼50 %/min) and most substantial mass loss (∼55 %) for both T1 and T5 pellets. Notably, the T5 pellet demonstrates a lower ignition temperature (207 °C, at 20 °C/min) and higher burnout (457 °C at 10 °C/min) compared to the T1 pellet, indicating its superior suitability for combustion. The combustion efficiency ranges from 61.0 to 99 % within the temperature range of 300 to 700 °C, similar to coal combustion. Additionally, thermodynamic properties (Di, Db, C, and S) suggest the promising potential of WSP as a bioenergy feedstock. Furthermore, T1 pellets demonstrate higher ignition temperatures (Ti) than T5, indicative of rapid combustion and lower energy potential. burnout temperatures (Tb) revealed intricate results in both scenarios. These findings hold significance for the design of gasification or combustion reactors and the industrial utilization of WSP biomass. The insights gathered from this study offer valuable guidance for designing and enhancing bioenergy systems and fostering sustainable practices in utilizing agricultural residues for energy production.

Solid waste management is one of the biggest challenges of the current era. The combustible fractions in the waste stream turn out to be a good energy source if converted into refuse-derived fuel. Researchers worldwide are successfully converting it into fuel. However, certain challenges are associated with its application in gasifiers, boilers, etc. to co-fire it with coal. These include high moisture content, low calorific value, and difficulty to transport and store. The present study proposed torrefaction as a pretreatment of the waste by heating it in the range of 200 °C–300 °C in the absence of oxygen at atmospheric pressure. The combustible fraction from the waste stream consisting of wood, textile, paper, carton, and plastics termed as mixed waste was collected and torrefied at 225 °C, 250 °C, 275 °C, and 300 °C for 15 and 30 min each. It was observed that the mass yield and energy yield decreased to 45% and 62.96% respectively, but the energy yield tended to increase by the ratio of 1.39. Proximate analysis showed that the moisture content and volatile matter decreased for torrefied samples, whereas the ash content and fixed carbon content increased. Similarly, the elemental analysis revealed that the carbon content increased around 23% compared to raw samples with torrefaction contrary to hydrogen and oxygen, which decreased. Moreover, the higher heating value (HHV) of the torrefied samples increased around 1.3 times as compared to the raw sample. This pretreatment can serve as an effective solution to the current challenges and enhance refuse-derived fuel's fuel properties.

Biomass is an organic substance widely available in nature as a fresh or a waste material considered renewable energy that aligns with the zero-carbon scheme to reduce the dependency on fossil fuels. However, after conversion, biomass's physical or chemical properties highly affect biofuel characteristics. A variety of instruments can be used to figure out biofuel reactivity. Considering commonly adopted instruments, thermogravimetric analysis (TGA) is a simple, fast, and efficient way to determine biofuel properties and reactivity. The TGA method has the capability to analyze the biofuel properties (proximate analysis: moisture, volatile matter, fixed carbon, and ash) and combustion features of biomass (such as ignition, reactivity, etc). Most importantly, the TG curvatures (TGA and DTG) reveal the behavior of the biofuel during the thermodegradation process. As a consequence, the quality and quantity analyses on the biofuel properties and reactivity can be investigated comprehensively. Moreover, some TGA integration with artificial intelligence (AI) has been studied to better understand biofuel management and technology for future development. The outcome for the TGA-AI integration may obtain an excellent result with the fit quality value R2 >95 %. This study aims to comprehensively review relevant research using TGA to analyze the lignocellulosic biofuel properties and reactivity. Moreover, the discussion in this study is extended to perspective, challenges, and future work.

The present study compares the kinetics and thermodynamics of the pyrolysis process of coffee and tea waste with respect to their physicochemical properties to analyze their potential as an energy and carbon source. Coffee and tea waste exhibit a promising source as a biofuel that has gross calorific values of 22.7 MJ kg−1 and 20.2 MJ kg−1, with significant differences in the overall volatile conversion of 76 % and 65 %, and as final carbon with a yield of 22 % and 31 %, respectively. Kinetic analyses using isoconversional methods show a trend of activation energy and frequency factor with conversion for both samples, with a significant difference at a conversion beyond 0.6 due to the higher lignin content in coffee waste. The predicted master plots indicate complex pyrolysis kinetics for both samples. Furthermore, the reaction kinetics determined by the multivariate regression approach, assuming parallel independent reactions of the nth order applicable to all heating rates, provide the individual mass change and carbon yield of each reaction process that can be controlled using experimental conditions. Finally, the thermodynamic parameters indicate that the pyrolysis process of both coffee and tea waste is nonspontaneous and endothermic, and its reactivity increases with conversion.

In this study, the combustion behavior of ca-rich oil shale, spruce biomass, and their blends under air and oxyfuel environments of 21/79 % and 30/70 % O2/CO2 like conditions were investigated. Non-isothermal thermogravimetric (TG) experiments coupled with a quadrupole mass spectrometer (MS) were conducted to study individual fuels and their blends at 1:0, 4:1, 3:2, 2:3, 1:4, and 0:1 (0, 20, 40, 60, 80 and 100 wt.% Biomass) under three different heating rates 10, 30 and 50°C/min. Co-combustion synergistic along with the kinetic analysis by the isoconversional Friedman method has been carried out to evaluate the combustion process.The results show that the addition of biomass enhanced combustion performance and reduced burnout temperatures. Under oxy conditions, the ignition temperatures stabilized with a biomass ratio > 40 %. Ash content was reduced with biomass addition and when switching from air to oxyfuel combustion, the temperature of blends’ carbonate decomposition was stable at ∼ 720 °C. A positive synergistic effect in the devolatilization and the combustion of light hydrocarbons occurred at higher biomass ratios. Yet, the char oxidation peaks were below zero indicating a negative effect under 21 % of inlet O2. With increasing the heating rate, the negative synergistic effect was weakened for the three combustion atmospheres. SO2 emissions were reduced with increasing biomass ratio and increased under oxy mode along with H2O release. The activation energy (E) was lower in oxy conditions than in air mode for individual fuel and their blends, compared to the OS sample, the reduction was higher with increasing BM ratios and for the BM fuel. Overall, this study determines the appropriate conditions for the co-combustion of oil shale and spruce biomass under air and oxy modes for future carbon-negative capture applications in industrial oil shale combustion boilers.

Investigations on the kinetics of bamboo pyrolysis frequently involve thermogravimetric analysis (TGA). The major mass loss while performing bamboo pyrolysis in TGA is found to occur approximately between 240 and 350 °C, termed the devolatilisation stage. A single reaction mechanism does not clearly define the number of complex reactions occurring simultaneously in the devolatilisation stage, as done in previous studies. Hence, this research focuses on stating reaction mechanisms for smaller temperature ranges made based on conversion rate. From the implementation of this novel approach, it is seen that till the peak temperature of differential thermogravimetry (DTG) is reached or till the decomposition rate reaches maximum, temperature is the most dominating factor; thereafter, heating rate dominates the bamboo pyrolysis process. This is assured with the help of thermodynamic parameters analysis. This further will provide insight into the design, scaling up, optimisation, and commercial application of bamboo pyrolysis systems. [ABSTRACT FROM AUTHOR]

Biomass, hydrochar, coal and hydrochar/coal blends have been proposed as alternative energy sources to coal. Given that the new fuels are derived from biomass, which is highly reactive, it is necessary to investigate their potential for spontaneous combustion (SPONCOM). Through the characteristics of coal discard, biomass, hydrochar, and hydrochar mixed at different ratios with discard coal, this study examined the factors that contribute to SPONCOM. The SPONCOM liability of these fuels was examined using the thermogravimetric analysis (TGA) and the Wits-Ehac index. The physicochemical analysis revealed an increase in the energy characteristic of the hydrochar produced from biomass. All samples showed a transmittance of the C=O stretch, which promotes SPONCOM, according to the results of the Fourier Transform Infrared Spectroscopy (FTIR) analysis. The TGA findings revealed that biomass is highly reactive, while discard coal was found to be non-reactive. A significant correlation was seen between the $T{G_{spc}}$TGspc index and the physiochemical properties of the samples. The Wits-Ehac results showed that biomass had the lowest SPONCOM liability index, while the 50% hydrochar/50% discard coal blend had the highest SPONCOM liability index. There was no correlation between the TGA and Wits-Ehac results, as the Wits-Ehac results showed some inconsistencies, particularly for samples derived from biomass. This study establishes the mechanism responsible for SPONCOM of hydrochar blended with coal in relation to their properties using the TGA. In addition, contributed to the understanding of techniques for predicting the SPONCOM of likely fuels for this application. [ABSTRACT FROM AUTHOR]

In this work, biosynthesized nanoparticles (Cr2O3) NPs were extracted by licorice root and proven by AFM technique to have a particle diameter of 14.99 nm. These particles were superimposed on polypropylene, and nanocomposites were synthesizes and diagnosed using different techniques, such as FT-IR, SEM, EDS, XRD, TG, DTA, and DSC. To identify the shapes, sizes, and nature of the particles of nanocomposites synthesized in an environmentally friendly way using the mentioned techniques, inhibitory actions of microorganisms were studied using several types of bacteria and fungi. To identify the protective role of environmentally friendly nanoparticles, the antimicrobial activity of the synthesized nanoparticles was characterized by green methods. Antioxidant activity was calculated by DPPH, and acceptable results were obtained for scavenging free radicals. [ABSTRACT FROM AUTHOR]

Soil thixotropy plays an important role in many engineering practices, which recently has been drawn an increasing attention by many researchers. In this paper, an experimental investigation on the thixotropy of deepwater marine clays in the South China Sea was carried out. The thixotropy-induced changes of undrained shear strength were measured by fall cone method, and the microscale evolution of soil structure, particularly the change of various types of water, was observed and quantified via employing scanning electron microscopy and thermogravimetric analysis, respectively. The test results show that the thixotropy strength ratios of all deep-sea clays increase quickly at the early stage (before about 10 days), then followed by a gradually lower increasing rate with prolonged time. The microstructural evolution of clay during thixotropic hardening is characterized by the transformation from a dispersed structure with parallel-arranged particles to a well flocculated one. The different types of water and their changes of mass fraction with thixotropic time could be well classified and quantitatively measured by thermogravimetric analysis, in which both the weakly and strongly bound water contents decrease, with the corresponding increase in the free water fraction. The thixotropic mechanism was then revealed from the perspective of the microstructural evolution and the adjustment of the thickness of bound water. The recovery of strength is majorly attributed to the forming and strengthening of inter-particle bonds or contacts and the adjustment of bound water layer. This research could help to provide a deeper insight into the inner reason of soil thixotropy. [ABSTRACT FROM AUTHOR]

Polyvinyl chloride remains one of the most prevalent polymers in the industry, yet its substantial environmental impact, attributed to its fossil origin, prompts the exploration of innovative solutions. Composites, particularly bio-composites, emerge as promising alternatives to mitigate the ecological footprint of PVC while enhancing its characteristics. This study addresses this concern by presenting the development of a bio-composite comprising 90% PVC and 10% biological filler derived from bovine horn, renowned for its high keratin content. The primary objective was to create an innovative, environmentally friendly, and sustainable material. To rigorously assess the properties and thermal stability of this bio-composite, a comparative thermogravimetric analysis was conducted against virgin PVC. The results reveal the superior thermal stability of the biocomposite compared to virgin PVC, particularly beyond 280 ℃. This enhancement is attributed to the substantial presence of keratin in the biological filler, constituting nearly 90% of the horn biomass. Notably, the observed mass loss in the bio-composite is lower than that of virgin PVC at temperatures exceeding 280?. This research underscores the potential of bio-composites, specifically those incorporating bovine horn-derived filler, as promising alternatives to mitigate the ecological footprint of PVC while concurrently improving its thermomechanical characteristics. The innovative material developed in this study holds promise for sustainable applications in various industries, aligning with the growing demand for environmentally conscious alternatives. [ABSTRACT FROM AUTHOR]

The reduction of Ce cations in CeO2 can be enhanced by their partial substitution with Fe cations. The enhanced reduction of Ce cations results in a considerable increase in the reaction rates for the thermal water-splitting reaction when compared to CeO2 alone. This mixed oxide has a smaller crystallite size when compared to CeO2, in addition to a smaller lattice size. In this work, two Fe-substituted Ce oxides are studied (Ce0.95Fe0.05O2-δ and Ce0.75Fe0.25O2-δ; δ < 0.5) by core and valence level spectroscopy in their as-prepared and Ar-ion-sputtered states. Ar ion sputtering substantially increases Ce4f lines at about 1.5 eV below the Fermi level. In addition, it is found that the XPS Ce5p/O2s ratio is sensitive to the degree of reduction, most likely due to a higher charge transfer from the oxygen to Ce ions upon reduction. Quantitatively, it is also found that XPS Ce3d of the fraction of Ce3+ (uo, u′ and vo, v′) formed upon Ar ion sputtering and the ratio of Ce5p/O2s lines are higher for reduced Ce0.95Fe0.05O2-δ than for reduced Ce0.75Fe0.25O2-δ. XPS Fe2p showed, however, no preferential increase for Fe3+ reduction to Fe0 with increasing time for both oxides. Since water splitting was higher on Ce0.95Fe0.05O2-δ when compared to Ce0.75Fe0.25O2-δ, it is inferred that the reaction centers for the thermal water splitting to hydrogen are the reduced Ce cations and not the reduced Fe cations. These reduced Ce cations can be tracked by their XPS Ce5p/O2s ratio in addition to the common XPS Ce3d lines. [ABSTRACT FROM AUTHOR]

A coordination polymer [Cu2 (μ3-OH)(1,3-BIP)(BTC)]n (SNUT-20) was constructed by 1,3-di(1H-imidazol- 1-yl)propane (1,3-BIP), benzene-1,3,5-tricarboxylic acid (H3BTC) and Cu(NO3)2·3H2 O under solvothermal method. Its structure was confirmed by elemental analysis (EA), thermogravimetric analysis (TGA), FT-IR and single crystal X-ray diffraction. Single crystal X- ray diffraction exhibits that SNUT-20 is a 3D framework with a tetranuclear copper cluster as a secondary structural unit, which forms a binodal (3, 8)-connected topology by further ligation of mixed ligand. In addition, SNUT-20 exhibits good photocatalytic degradation performance for rhodamine B (RhB), methylene blue (MB) and methyl orange (MO), RhB, MB and MO reach 81.5%, 89.4% and 48.3% of the degradation rates, respectively. [ABSTRACT FROM AUTHOR]

In this article, the effect of irradiation dose and incorporated nanoparticles of kaolin (K) and graphite (G) on the lattice structure, thermal analysis, electrical conductivity, morphology, and mechanical properties of high-density polyethylene (HDPE) were studied. Infrared spectroscopy analysis (FTIR), transmission electron microscopy (TEM), and X-ray diffraction (XRD) were used to characterize and prove the nanostructure of kaolin and graphite. Subsequently, HDPE was reinforced with a fixed percentage of nanokaolin at 3 phr and different contents of nanographite at 2 and 4 phr via melt-mixing and then molded by the hot press to sheets of suitable thickness. The fabricated sheets will be exposed to various gamma radiation doses at 50, 100, and 150kGy to investigate the impact of ionizing radiation on the prepared nanocomposites. It was found that the presence of a fixed percent of nanokaolin and graphite nanoparticles at 2 phr inside the HDPE matrix improved various properties of the prepared nanocomposites. Furthermore, the synergistic effect of nanokaolin with nanographite and irradiation doses led to the improved crystal structure, thermal analysis, mechanical properties, and electrical conductivity of HDPE nanocomposites. [ABSTRACT FROM AUTHOR]

• Microalgae and sewage sludge were converted into hydrochars at three temperatures. • High addition of sewage sludge affected formation and composition of secondary char. • Less sewage sludge led to higher C retainment and fixed C in hydrochars. • Presence of toxic compounds in microalgae may limit potential utilization. The role of microalgae cultivation in wastewater treatment and reclamation has been studied extensively, as has the potential utility of the resulting algal biomass. Most methods for processing such biomass generate solid residues that must be properly managed to comply with current sustainable resource utilization requirements. Hydrothermal carbonization (HTC) can be used to process both individual wet feedstocks and mixed feedstocks (i.e., co-HTC). Here, we investigate co-HTC using microalgae and digested sewage sludge as feedstocks. The objectives were to (i) study the material's partitioning into solid and liquid products, and (ii) characterize the products' physicochemical properties. Co-HTC experiments were conducted at 180–250°C using mixed microalgae/sewage sludge feedstocks with the proportion of sewage sludge ranging from 0 to 100 %. Analyses of the hydrochar composition and the formation and composition of secondary char revealed that the content of carbonized material in the product decreased as the proportion of sewage sludge in the feedstock increased under fixed carbonization conditions. The properties of the hydrochars and the partitioning of material between the liquid phase and the hydrochar correlated linearly with the proportion of microalgae in mixed feedstocks, indicating that adding sewage sludge to microalgae had weak or non-existent synergistic effects on co-HTC outcomes. However, the proportion of sewage sludge in the feedstock did affect the secondary char. For example, adding sewage sludge reduced the abundance of carboxylic acids and ketones as well as the concentrations of higher molecular weight cholesterols. Such changes may alter the viable applications of the hydrochar. [ABSTRACT FROM AUTHOR]

Bamboo powder has a high risk of fire and dust explosion during production, manufacturing, transportation and storage. It is of great significance to study the combustion characteristics of bamboo powder and its influencing factors for finding suitable flame retardants. So far, the relative study is more focused on bamboo rather than bamboo powder. In this paper, the combustion characteristics of bamboo powder were measured by TGA. Ignition temperature, burnout temperature, combustion rate and comprehensive combustion index were used as evaluation criteria. The influence of particle size and heating rate was quantitatively analyzed. The results showed that the ignition and burnout temperature increased with the increase in heating rate. The S value at the heating rate of 40 °C min−1 was 22 times of that at 5 °C min−1. The finer the particle size, the higher the S value, and the S value of 400-mesh bamboo powder can reach 2.0 × 10–5. The flame retardant properties of six inorganic compounds on bamboo powder were studied. According to the S value, the order of flame retardant properties at the best concentration was CaCl2 ˃ NH4H2PO4 ˃ MgCl2 ˃ Na3PO4 ˃ NH4Cl ˃ APP. Among them, 33% CaCl2 had the best flame retardancy. [ABSTRACT FROM AUTHOR]

Thermogravimetric analysis (TGA) is a powerful technique and useful method for characterizing biomass as a non-conventional fuel. A TGA apparatus has been utilized to experimentally investigate the impact of biomass feedstock diversity on the performance of the gasification of hardwood (HW), softwood (SW) pellets, and refuse-derived fuel (RDF) materials. The solid conversion rate and the volatile species formation rate have been estimated to quantify the rates of devolatilization for each material. In addition, the combustion kinetic characteristics of the three biomass feedstocks were investigated using TGA at different heating rates, and a thermal kinetic analysis was conducted to describe the gasification process. Therefore, the kinetic parameters have been evaluated for different thermal reactions and non-isothermal kinetic models that depend on the relationships between heating rates and temperature profiles. The results show that the amount of tar content from the RDF was higher than that of pure hardwood and softwood feedstocks. Hence, tar removal must be part of any process using syngas produced from RDF feedstocks in a gas engine to produce electricity. [ABSTRACT FROM AUTHOR]

In order to explore the influence of pickling on the pyrolysis characteristics and adsorption performance of biomass, this paper used pickled rice husk as raw material, and used TG-FTIR coupling instrument to explore the pyrolysis characteristics and product changes of rice husk; The Coats-Redfern (C-R) method was used to analyze the pyrolysis kinetics, and the adsorption performance of pyrolysis biochar on heavy metal Cu was investigated. The results show that pickling can effectively reduce AAEMs, change the pyrolysis path, increase the release of volatiles, and increase the calorific value of raw materials by about 17.10%. The surface of rice husk retains abundant functional groups, and the vibration of characteristic peaks is more intense. The C-R kinetic analysis showed that the pyrolysis process was consistent with the reaction order n = 1, and the influence on the activation energy of rice husk was sulfuric acid > phosphoric acid > nitric acid. The pickling pyrolysis biochar can promote the adsorption of heavy metal Cu2+ in the aqueous phase, the adsorption capacity is up to 41.4 mg·g-1, and the adsorption efficiency is up to 82.8%. [ABSTRACT FROM AUTHOR]

It is well known that lubricating oils reduce the friction coefficient between two surfaces in contact. Since petroleum lubricants are toxic and have a low biodegradability, they are typically not appropriate for the environment. As a result, as public worries about a pollution-free environment grow, so does the demand for lubricants that are acceptable to the environment. The primary rationale for utilizing vegetable oils in forthcoming bio-lubricant formulations is their high lubricating performance, low toxicity, sustainable, and biodegradability. Plant oils hold great potential as a foundational fluid for bio-lubricants, since their synthetic and vegetable oil-based esters provide the most environmentally friendly option for creating lubricants. In this study, Jatropha and Jojoba raw oil were chemically modified via epoxidation followed by transesterification to produce bio-lubricants. Thus, the aim of this work is to develop a bio-lubricant from jatropha and jojoba methyl ester, further adding nanoparticles multiwalled nanotubes and titanium dioxide for improvement of tribological properties. The chemical modification of the jatropha and jojoba oil results in a decrease in iodine value, resulting in the breaking of carbon bonds. Viscosity tests were performed using the Anton Par MCR 92 Rheometer, with temperature ranging from 30°C to 80°C. Thermal stability measurements of bio-lubricants were performed using PerkinElmer’s Thermogravimetric analyzer-4000 instrument and thermal degradation temperature for Epoxidized Jatropha-sulfuric acid, Epoxidized Jatropha-hydrochloric acid, Epoxidized Jojoba-sulfuric acid and Epoxidized Jojoba-Hydrochloric acid samples are 238°C, 224°C, 230°C, and 244°C, respectively. The 94.68% and 79.85% reduction in wear was obtained for Epoxidized Jojoba with hydrochloric acid, titanium dioxide and epoxidized Jatropha with sulfuric acid, multiwalled carbon nanotubes in comparison with their epoxidized samples. The coefficient of friction of Epoxidized Jatropha with sulfuric acid, multiwalled carbon nanotubes and Epoxidized Jojoba with Hydrochloric acid, Titanium dioxide sample was found to be 0.061 and 0.059, respectively [ABSTRACT FROM AUTHOR]

Robust mathematical treatment of the Ozawa/Flynn/Wall isoconversion method is conducted to determine the value and uncertainty of the activation energy and pre‐exponential factor for the degradation of polypropylene in thermogravimetric analysis experiments at constant heating rates. The present work employs mathematical models and uncertainty propagation techniques based on the Guide to the Expression of Uncertainty in Measurement to estimate the Arrhenius activation energy and pre‐exponential factor due to the uncertainty of the integration constant b, both in a linear and a third‐degree reciprocal polynomial model with respect to x. The error arising from Doyle's linear approximation in the improper integral of temperature in the Arrhenius equation is examined, and an alternative method is proposed to correct this error, reducing it to 0.032% in the working interval of −200 ≤ x ≤ −15, where x = −E/RT. Given the increased sensitivity of modern thermogravimetric analysis equipment, these improvements are considered essential for obtaining reliable results that align with experimental precision limits compared to previous works. Thus, this allows for the development of an enhanced quality assurance framework by providing more robust uncertainty estimation and a better understanding of the method. Moreover, this approach can be applied to other similar polymer system. [ABSTRACT FROM AUTHOR]

The solubility of the components in the ZnSO4 - KNO3 - H2O system was studied by the visual-polythermal method in the temperature range from -7.0°C to 42.0°C. The phase diagram delimits the fields of ice crystallization, KNO3, K2SO4·ZnSO4·6H2O, and ZnSO4. A solubility diagram was constructed, and a new compound K2SO4·ZnSO4·6H2O was separated. The new compound was identified by chemical, X-ray phase, thermogravimetric, and IR spectroscopic analysis. [ABSTRACT FROM AUTHOR]

Phenylboronic acids (PBAs) form stable complexes with fluoride. The effect of type (methoxy-, formyl-, and acetyl-) and position (ortho-, meta-, and para-) of electron-donating substitutions on the hydrolytic stability and acidity of PBAs, as well as their spectroscopic and physicochemical properties and their usage in spectrofluorimetric fluoride determination, were investigated. Thermal stabilities, relative predisposition, and resistance to dehydroboronation of related PBA isomers were investigated in detail and compared with the use of thermogravimetric analysis and differential scanning calorimetry profiles. Dehydroboronation reaction leads to the synthesis of related new cyclic anhydric forms — specifically named boroxines — which are clearly distinguished by Fourier transform infrared spectroscopy. PBAs were used for the complexation of fluoride for spectrofluorimetric fluoride determination in dental formulations [toothpastes (TPs) and mouth rinses (MRs)] and beverages [mineral waters (MiWs)]. Determination was done by fluorescence quenching of PBAs in response to increasing fluoride concentration. The regression equation was y = –15.336x + 983.17 (R2 = 0.9931), and was linear in the 1.4–3.0-mM range. Determinations were performed with relative errors (%) in a range of –5.60 to +1.23, –2.01 to +5.69, and –4.16 to +2.54 for MRs, TPs, and MiWs, respectively, relative to fluoride levels of commercial samples. Chemometric analyses (cluster analysis, CA, principal component analysis, PCA) were performed on the same real samples. Raw fluorescence data was investigated by PCA to check their significance in chemometric discrimination. Dendograms and score plots successfully discriminated samples in related groups. This is the first demonstration of spectrofluorometric fluoride determination based on the quenching of related isomers of PBAs thus far, also the potential of raw fluorescence data of these PBAs for chemometric discrimination studies on related pharmaceutical samples was highlighted for the first time. [ABSTRACT FROM AUTHOR]

To evaluate the effect of different wall material (WM) matrices followed by homogenisation to encapsulate chia seed oil (CSO) using freeze drying technology. CSO was encapsulated using three ratios (100/0, 50/50, and 100/0) of two WM matrices: MTS/WPC (modified tapioca starch–whey protein concentrate) and MD/WPC (maltodextrin–whey protein concentrate). The evaluation included encapsulation efficiency (EE), oxidative stability, and α-linolenic acid (ALA) retention. Homogenised microcapsules (-H) were then assessed for storage and thermal stability, along with cumulative oil release. The MD-WPC-H 50/50 microcapsules had superior EE (97.32%), higher ALA retention (60.2%), storage stability (up to 30 days), higher thermal stability (up to 700 °C), and desirable oil release in simulated condition. Selecting suitable WM and homogenisation is key for improving EE, storage, thermal stability, and targeted release. The CSO microcapsule can serve as a functional ingredient to improve the quality of diverse food products. [ABSTRACT FROM AUTHOR]

The subjects of this research are the burial clothes of Polish King Sigismund III Vasa and his wife Constance, which were woven and embroidered with silk and metal threads. Fragments of the textiles underwent spectroscopic, spectrometric, and thermogravimetric analyses. The hydrofluoric acid extraction method was improved to isolate various classes of dyes from the textile samples that had direct contact with human remains. High-performance liquid chromatography, coupled with diode array and tandem mass spectrometry detectors with electrospray ionization (HPLC-DAD-ESI-MS/MS) facilitated the detection and identification of colorants present in the textiles. Cochineal, indigo-, madder-, orchil-, and tannin-producing plants were identified as the sources of dyes used. Scanning electron microscopy with an energy-dispersive X-ray detector (SEM-EDS) was employed to identify and characterize the silk fibers and mordants and the metal threads. The presence of iron, aluminum, sodium, and calcium in the silk threads suggests their potential use as mordants. The analysis of the metal threads revealed that most of them were made from flattened gilded silver wire, with only a few being cut from a sheet of metal. Typical degradation mechanisms of metal threads were shown, resulting from both burial environment and earlier manufacturing process, and the use of the textiles in clothing, i.e., a significant loss of the gold layer was observed in most of silver gilt threads, caused by abrasion and delamination. The results of the thermal analysis confirmed the presence of silk and silver threads in the examined textiles. [ABSTRACT FROM AUTHOR]

Phosphorylated cellulose can be an intrinsic flame retardant and a promising alternative for halogenated fire inhibitors. In this study, the mixture of di-ammonium hydrogen phosphate (DAP) and urea (U), containing phosphate and nitrogen groups, was applied to attain fire inhibitor properties. Functional groups of cellulose were grafted with phosphorous by keeping the constant molar ratio of 1/1.2/4.9 between anhydroglucose units of cellulose/DAP/U in different concentrations of bleached kraft pulp. Phosphorus concentrations were determined using the ICP hrOES method, and paper sheets were made using the Rapid Köthen apparatus. The tensile strength of phosphorylated cellulose increased twice compared with unmodified cellulose when the phosphorous concentration increased to 10,000 g/kg. An increase in the tensile index comes from the higher freeness of pulp and cross-linking of the phosphorous group between cellulose fibers. Remarkable fire retardancy effects were achieved in cellulose concentrations above 5 wt%. The raised phosphorous concentration above 10,000 g/kg due to the phosphorylation process caused the formation of a char layer on a cellulose surface and the nonflammable gas emission. That effect was indirectly confirmed by reducing the combustion temperature and HRR by 50 and 45%, respectively. Due to increasing phosphorus concentration in cellulose sheets, cellulose's fire and strength properties increased significantly. [ABSTRACT FROM AUTHOR]

Solid fossil fuels still support the development of the energy and chemical industry. The clean and efficient utilization of solid fossil fuels can effectively alleviate the problems of energy shortage and environmental pollution. An in‐depth understanding of the kinetic process, models, and mechanism of pyrolysis of solid fossil fuels is also of great significance for the exploration and utilization technologies of petroleum resources. Thermogravimetric analysis is an effective method to study the pyrolysis process and kinetics with the advantages of high sensitivity, repeatability, and reliability for data acquisition. Researchers have conducted a lot of research on the thermogravimetric kinetics of solid fossil fuels in recent years, but there is a lack of systematic summary and comparison of kinetic methods, research progress, and trends. Therefore, a comprehensive study on pyrolysis kinetic principles, methods, and models of solid fossil fuels by thermogravimetric analysis is carried out in this paper. The influencing factors of pyrolysis kinetics of solid fossil fuels using thermogravimetry are elaborated and discussed in detail. This study also provides progress in recent years and prospects of thermogravimetric kinetics of solid fossil fuels. It is expected that this paper can provide certain technical support and theoretical guidance for the research on pyrolysis kinetics based on thermogravimetric analysis, and the exploration and development, clean, and efficient utilization of solid fossil fuels. [ABSTRACT FROM AUTHOR]

New transition metal complexes of cobalt(II), nickel(II), copper(II) and zinc(II) with new Schiff base [HLp] derived from pyrene-1-carbaldehyde and 4-Amino-3-mercapto-5-oxo-1,2,4-triazine were synthesized and characterized by elemental analysis, 1H-NMR, FT-IR, UV-Visible, ESR spectral studies, magnetic moment measurements and cyclic voltammetry. Results prove that [HLp] acts as bidentate ligand. Low conductance data reveal non-electrolytic nature of the complexes. The spectroscopic data and magnetic moment values along with elemental analytical data support octahedral geometries for Co(II), Ni(II), Zn(II) complexes and square planar geometry for Cu(II) complexes. ESR spectra of Cu(II) complexes exhibited g values trend as g ∥ > g ⊥ > g e. The nephelauxetic ratio (β) along with orbital reduction factors (K values) report the covalent nature of the metal-ligand bonds in complexes. Thermal analysis was also carried out to propose the composition of complexes and to determine their thermal stability. Coats-Redfern method was employed to evaluate some kinetic parameters of thermal degradation processes. In vitro antimicrobial properties of all synthesized compounds were investigated. After assessing the inhibition zones, metal complexes have been found more antimicrobial active than the Schiff base against both bacterial as well as fungal strains. Metal complexes also showed remarkable fluorescence and antioxidant properties. [ABSTRACT FROM AUTHOR]

Changes in water content have a significant impact on the consolidation of peat soil. Through the water content test and thermogravimetric analysis test, the water content, and the free water, weakly bonded water and strongly bonded water content of peat soil with different organic content in Yunnan Province (China) at different load levels and consolidation times were studied. The results show that the free water in peat soil samples was discharged when the temperature was less than 60 °C; the weakly bound water was released at 60 − 110 °C; and the strongly bound water was dehydrated at 110 − 200 °C. During the consolidation of peat soil, the water content in different states changed significantly. In the primary consolidation stage, the proportion of free water in the peat soil samples decreased by approximately 20%, while the proportion of weakly bound water increased slightly. In the secondary consolidation stage, the proportion of water in different states did not change considerably. In the third consolidation stage, the proportion of free water increased, and the proportion of weakly bonded water causing creep decreased by approximately 11%. For the undisturbed and deformed peat soil, the contents of free water and bound water increased with increasing total water content, but the ratio of free water to bound water remained relatively stable at approximately 1:2. [ABSTRACT FROM AUTHOR]