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[Display omitted] • Glass fiber wind turbine blades (WTBs) can provide raw material to produce cement. • Glass fiber WTBs can serve as fuel and replace coal to produce cement. • High boron in some glass fiber WTBs might limit replacement rates. • Combustion of fossil-fuel polymer in WTBs can slightly reduce plant CO 2 emissions. • Glass fiber wind turbine blades are compatible with the cement production process. The objective of this paper is to evaluate the feasibility of co-processing wind turbine blade (WTB) material in cement manufacturing to provide an end-of-life means to divert the solid waste of decommissioned WTBs from landfills. Many WTBs consist primarily of glass fiber reinforced thermoset polymers that are difficult to recover or recycle. Portland cement is produced world-wide in large quantities, requiring immense quantities of raw materials (mostly calcium oxide and silicon oxide) and kiln temperatures approaching 1,450 °C. This work contributes analyses of WTB material composition, and predicts the energy provided through the combustible components of the WTBs and raw material contributions provided by incorporating the incombustible components of the WTBs to produce cement. Approximately 40 to 50 % of the WTB material will contribute as fuel to cement production, and approximately 50 to 60 % of the WTB material is expected to be incombustible. One tonne of WTB material can displace approximately 0.4 to 0.5 tonne of coal, while also contributing approximately 0.1 tonne of calcium oxide and 0.3 tonne of silicon oxide as raw material to the cement production process. The glass fiber WTB tested had an average boron content of 4.5 % in the ash. The effects of this high boron content on the cement and its production process should be evaluated. Co-processing WTBs in cement plants will slightly reduce combustion-related CO 2 emissions due to avoided calcination. It seems feasible to co-process glass-fiber reinforced WTBs in cement production as WTBs provide suitable raw materials and compatible fuel for this process. [ABSTRACT FROM AUTHOR]

At present, under the background of the excess product oil market, "reducing oil products and increasing chemical raw materials" has become the mainstream trend in the chemical industry. In recent years, ZSM-5 zeolite catalyst has been widely used in the aromatization of FCC gasoline, but its modification to improve its aromatization catalytic performance is still not perfect. Therefore, based on the existing process technology, the effect of pseudo-boehmite on the aromatization performance of Zn-P-Al/ZSM-5 catalysts was investigated on a small continuous fixed-bed reactor using 75-120 °C fractions of FCC gasoline as feedstock. The results show that the aromatization performance of Zn-P-Al/ZSM-5 catalyst is better than that of Zn-P/ZSM-5 and HZSM-5, and the best aromatization performance is obtained when the pseudo-boehmite ratio is 30%, the aromatics content and aromatics yield in liquid products are 90.82% and 54.38%, respectively. The results of catalyst characterization are consistent with those of catalyst evaluation. [ABSTRACT FROM AUTHOR]

The novel yellow color compounds Ca 2 LiSc 1- x B 4 O 10 : x Cr with NIR emission were successfully synthesized by the solid state method. All samples are of pure phases through X-ray diffraction results. The oxidation state of Cr dopant in this borate is confirmed to be mix-valence (+3 and + 6) using XPS analysis. Based on the analysis of Cr oxidation state and UV–Visible spectrum, the Cr–O charge transfer from Cr6+ octahedral sites in the visible light range is the reason for the yellow color. Meanwhile, a near infrared (NIR) broadband emission at 800 nm with FWHM of 141 nm is from Cr3+ in octahedron, which could be effectively excited by 495 and 630 nm. The yellow chromophore and NIR lumophore are successfully combined in Ca 2 LiScB 4 O 10 : Cr using economical raw materials through simple method, and may be applied in the field of yellow pigment and NIR phosphor. [ABSTRACT FROM AUTHOR]

Brine magnesia and fused Al 2 O 3 –ZrO 2 powder were used as raw material to prepare MgO–Al 2 O 3 –ZrO 2 (MAZ) refractory brick which was sintered at 1690 °C for 8 h in a tunnel kiln. Its resistance to slag corrosion of non-ferrous metallurgy was investigated. The phase and microstructure of the samples before and after corrosion were characterized by XRD, SEM and EDS. The results show that MAZ ternary metastable phase was formed during sintering, which then decomposes to finely dispersed MgO, MgAl 2 O 4 , and ZrO 2. Thus, highly uniform distribution of ultra-fine MgAl 2 O 4 and ZrO 2 in the matrix was achieved. The non-ferrous metallurgical slag is mainly composed of FeO and SiO 2. At high temperatures, when the material is subjected to slag corrosion, both (Mg, Fe)Al 2 O 4 and 2MgO·SiO 2 with high-temperature melt point were formed in the corrosion layer, effectively preventing further infiltration and corrosion of MAZ samples by slag. A model for the formation process of high dispersion of MAZ was explained, and a model for the corrosion mechanism between non-ferrous metallurgical slag and MAZ samples was established. [ABSTRACT FROM AUTHOR]

This effort aimed to investigate the differences between raw materials and thin films to enhance the film performance and get encouraging results. Barium strontium titanate (BST) is a solid solution consisting of titanate barium (BT) and titanate strontium (ST). BST powder was synthesized using the sol–gel process, and BST film was deposited using pulsed laser deposition (PLD). Barium, strontium acetate, and Ti-isopropoxide were utilized as raw material sources. XRD was used to characterize the BST perovskite crystal structure. The SEM and LCR meters revealed morphology surface and dielectric properties. XRD pattern shows a cubic structure phase. The particle size of the bulk exhibited 122.88 nm while the film particle size was 84 nm. The dielectric constant of the bulk shape exhibited was greater than the form of the films, which was attributed to different thicknesses, densities, defects, and porosity. [ABSTRACT FROM AUTHOR]

Using cellulosic micro/nanofibrils (MFC/NFC) in developing films for coatings and packaging has aroused industrial interest to replace plastic. This study proposes functionalizing packaging films composed of hybrid suspensions of 80 % titica vine (Heteropsis flexuosa) and 20 % Pinus to improve their mechanical properties. The MFC/NFC were produced by mechanical fibrillation and adding proportions of 1, 2.5, and 5 % of nanolignin, vegetal tannin, and synthetic termite saliva. Both suspensions had concentrations of 1 % (w/w). The MFC/NFC were evaluated for energy consumption, microstructural, and stability, while the films were for physical, optical, barrier, and mechanical properties. Films with nanolignin 2.5 % obtained lower WVP and degradation in water, with greater hydrophobicity and puncture strength. The treatment with tannin 1 % obtained higher density and lower porosity, while termite saliva 1 % presented higher tensile strength at around 53.1 MPa. The additives improved the quality index of the MFC/NFC (>51.1 points). It is concluded that adding different binders can help expand the use of MFC/NFC. New studies are essential to seek pre-treatments or alternative fibrillation methods to increase their application and efficiency for fiber cell wall fibrillation, in addition to the need for a deeper analytical understanding of the interactions of additives with cellulose. [ABSTRACT FROM AUTHOR]

Cocoa Pod Husk (CPH) is biomass waste from plantation activities which have the potential to be used as a companion fuel for low-rank coal (LRC). This study aims to find out the characteristics of combustion using the TGA-DTA testing. This experiment was carried out by testing the crushed CPH and LRC raw materials with a particle size of 40 mesh based on ASTM standards, then CPH was added to the LRC. The composition of adding CPH into the LRC is 10%, 30%, and 50%, respectively. The results of this experiment presented that there is an increase in combustion performance as a result of adding the CPH into the LRC. This is a result of a decrease in the burning temperature of volatile matters and ignition temperature. The optimum amount of addition which gives a significant increase in combustion performance is obtained by adding 10% CPH into the LRC. [ABSTRACT FROM AUTHOR]

The present study focuses on the synthesis and characterization of rare-earth titanates, specifically Re 2 TiO 5 (Re La, Nd, Sm), with a particular emphasis on their microwave dielectric properties. The factors influencing the synthesis of La 2 TiO 5 compound through the traditional solid-state method were thoroughly investigated, with a significant finding being the notable impact of moisture absorption in La 2 O 3. The impact of variations in rare-earth cation radii on the structure and dielectric properties was systematically analyzed. Re 2 TiO 5 (Re La, Nd, Sm) ceramics crystallized into an orthorhombic structure with space group Pnam, which was confirmed through Rietveld refinement. The resulting materials demonstrated exceptional microwave dielectric properties characterized by a low permittivity range of 13.72–17.39, high-quality factors ranging from 8331 to 17,795 GHz, and a significantly reduced temperature coefficient of resonance frequency (−33.2∼-12.6 ppm/°C). The correlation between microwave dielectric properties and structural characteristics (including ionic polarizability, packing fraction, and bond valence) was investigated. The exceptional potential of these rare-earth titanates lies in their ability to meet the stringent requirements for low signal transmission delay in wireless communication systems, owing to their advantageous low permittivity within the microwave frequency spectrum. [ABSTRACT FROM AUTHOR]

Addressing increased damage to hot metal ladle refractory linings from FeO x of scrap steel, Al 2 O 3 –SiC–C refractories were prepared at 1400 °C with corundum, SiC, graphite as raw materials, and fused magnesia as additives. The impacts of additives on phase changes, microstructure, and properties were researched. The findings indicate that the oxide layer of Al 2 O 3 –SiC–C refractories with in-situ generated MgAl 2 O 4 is denser than that of the blank sample after the oxidation test. This denser layer effectively inhibits the diffusion of O 2 , leading to a significant enhancement in oxidation resistance. After the corrosion test, it was observed that a part of Al 2 O 3 was wrapped by Mg(Al, Fe) 2 O 4 at the interface between the sample with generated in-situ MgAl 2 O 4 and the slag. This structure can ensure the integrity of the material structure and fix some Fe2+ to weaken its corrosion to the refractory components, and its corrosion resistance is higher than that of the blank sample. [ABSTRACT FROM AUTHOR]

Lightweight ceramic proppants are prepared using coal gangue, fly ash, and bauxite as raw materials, and a mixture of manganese dioxide and magnesium oxide is used as composite additives. The total content of the coal gangue and fly ash in the raw materials reaches up to 70 wt%. The effects of coal gangue and fly ash precalcination, sintering temperature, and composite additive content on the phase compositions, microstructures, and performances of the resulting ceramic proppants are studied in detail. The ceramic proppant prepared at 1285 °C using 1 wt% of the composite additive is composed of quartz, corundum, and mullite. It also presents the desired sphericity, roundness, and microstructure. The apparent density, bulk density, and breakage ratio of the ceramic proppant described above are 2.55 ± 0.06 g/cm3, 1.03 ± 0.02 g/cm3, and 8.30 ± 0.68% at 35 MPa, respectively. This ceramic proppant belongs to lightweight ceramic proppants and meets the requirement of the 5K grade in the standards of SY/T 5108-2014 and API STD 19C-2018. [ABSTRACT FROM AUTHOR]

Human geographers are increasingly concerned with how 'futures' are imagined and rendered governable, yet mostly their methods lack the sensitivity to explore the functioning of complex relations between heterogeneous actors across places. The world's electric vehicle (EV) sector is booming, presaging a widely expected decarbonised future, associated with a restructuring of the automobile industry as anticipated by proactive players. This paper interrogates the spatiality and politics of the EV future‐making through disentangling the translocal practices involved in realising Tesla's Gigafactory in Shanghai (TGS) as assemblage. Informed by interviews with industrial insiders and opensource information in Chinese and English, the article finds that, first, TGS's imagined future embodies a multiplicity of interdependent but divergent expectations, the coherence of which underlies the formation and operation of the TGS assemblage by virtue of the concerted actions of its member‐actors. Second, such coherence is conditional as designed by TGS's central planners—namely, Tesla and Chinese government agencies at central and local levels—for their differentiated but overlapping interests. The TGS's imagined future is rendered actionable, enrolling other agents at certain moments, through anticipatory practices of regulatory changes, strategic arrangements interweaving land and financing, firm acquisition and intra‐firm reorganisation linking up places in and outside China, as well as the selection of key suppliers and technological use of critical raw materials. Concluding after a sketch on the TGS's 'possible futures' and broader implications, the paper contributes an assemblage‐informed approach to disentangle futuremaking practices and generates timely insights into the 'future‐oriented' restructuring of the automobile industry. [ABSTRACT FROM AUTHOR]

Recently, the development of supported ionic liquid on magnetic nanoparticles (MNP) and multicomponent reactions in industry and academia has been a matter of intense study. In this new and environmentally benign synthetic methodology, a dihydroxyl functionalized basic ionic liquid precursor was immobilized onto the magnetic silica nanoparticles via covalent bonding to prepare a novel powerful basic catalyst (DHBIL@Si-MNPs). The synthesized catalyst was characterized extensively by various techniques. Also, the alkalinity of the DHBIL@Si-MNPs catalyst (pKb value) was obtained at 9.23. The catalytic activity of the prepared catalyst was investigated in a one-pot and three-component reaction between pyridine, phenacyl bromide, and thiocyanate to afford corresponding substituted imidazo [1,2-a] Pyridine derivatives under solvent-free conditions. Different spectroscopic methods were used to establish the structures of target compounds. The imidazopyridines were generated in excellent yields (80–98%) under the optimum conditions utilizing 10% by weight of DHBIL@Si-MNPs to pyridine, a molar ratio of 1.2: 1.2: 1 mmol (mmol), and a temperature of 100 °C. The present developed synthetic protocol permits the production of interesting medicinal compounds with high purity and different functional group tolerating abilities. Also, the other significant advantages of this protocol are highlighted by less reaction time, cleaner reaction profiles, avoidance of toxic catalysts, simplicity of the process, benign reaction conditions, use of available raw materials, and easy separation of products. The catalyst could be easily recycled from the reaction mixture using an external magnet thanks to its superparamagnetic and reused several times without any appreciable decrease in its reactivity and product yield. [ABSTRACT FROM AUTHOR]

The application of Topology Optimisation (TO) to help in the manufacture of metallic components in highly technological industries has increased recently. To equally benefit from TO, the construction industry must address its specific issues, such as adherence to code requirements and challenges in using cutting-edge software packages in complex joints with non-linear behaviour. To assist in such a challenge, the current study offers a methodology proposal to synthesise code and structural behaviour requirements into geometrical constraints for the optimisation problem of laminar steel parts under compression while integrating Non-linear Finite Element Analyses (NLFEA) that ensure the safety of the solution. It has been found that, for a real case-study, the initial volume of a connection's cover-plate can be decreased by up to 40% while maintaining the connection's original capacity and that a 30% volume decrease may be achieved while keeping the original plate capacity. In both cases, the plate's ultimate deformation capacity was enhanced. Evidence has been found that Linear Elastic TO may not provide safe-sided solutions for parts with an intrinsic non-linear behaviour. With the attained volume reductions, less raw materials may be consumed, assembly and transportation will be facilitated, and the goals of the sector's decarbonisation, energy intensity and sustainability will be favoured. [ABSTRACT FROM AUTHOR]

Li5FeO4 (LFO) is emerging as a promising prelithiation additive due to the high lithium donor capacity (>700 mAh g−1), cheap raw materials, good environmental adaptability, and reliable synthesis approach. However, LFO suffers from extremely poor air stability and the underlying mechanism remains elusive. Herein, LFO is subjected to different atmospheres (the main component of air) of O2, CO2, N2, and 30% humidity air to unravel its reaction mechanism with air and the interfacial chemistry. It is found that Li+ ions will escape from the LFO crystal lattice to construct Li2O, Li2CO3, and LiOH impurity phases with an obvious change of LFO surface morphology in contact with O2, CO2, and humidity air. These insulating species remarkedly inhibit Li+ ion diffusion from the material and thus lead to an increment of interfacial impedance and an apparent capacity degradation. Consequently, the initial charging capacity decays rapidly from 681.5 to 169.4 mAh g−1 (under O2) and to 54.8 mAh g−1 (under CO2), respectively. In this regard, a facile coating strategy is proposed on the surface of LFO to effectively improve its air stability. [ABSTRACT FROM AUTHOR]

The use of new materials in the field of biofuel production has been represented as a step in the development of remarkable catalysts. The use of lipases in the production of biodiesel is often seen as a cost-limiting step, as the operating expenses in recovering such catalysts can lead to unfeasible market expectations. In this study, hydroxyapatite (HAp) particles were evaluated as a support to immobilize commercial lipase, following application in ethyl ester synthesis. First, hydroxyapatite was synthesized through the co-precipitation method at constant pH and selected as a support to be used in enzyme immobilization. The characterization of the biocatalyst support materials produced was carried out using DRX, BET, FTIR, TGA, and SEM analysis. The lipase from Thermomyces lanuginosus was then immobilized in the matrices, and, subsequently, there was transesterification of the vegetable oil deodorization distillate (VODD). The biodiesel samples generated showed that they were within commercial standards, achieving ester conversion greater than 96.5%. Other properties such as density (0.87 g.cm−3) and viscosity (4.36 mm2.s−1) meet the specifications required by ASTM to be used as a biofuel. In the experiment planning technique, the results revealed an experimental trend and a defined behavior: a higher lipase loading in the immobilization and the use of temperatures in the range of 40–50 °C favor high conversions of ethyl esters. Thus, this confirms that the enzymatic chemical catalyst was able to form the main fatty acid esters even using a residual lipid raw material. [ABSTRACT FROM AUTHOR]

Hydrogen peroxide (H2O2), an environmentally friendly strong oxidant and energy carrier, has attracted widespread attention in photocatalysis. Artificial photosynthesis of H2O2 using water and oxygen as raw materials, solar energy as an energy source, and semiconductor materials as catalysts is considered a promising technology. In the past few decades, encouraging progress has been made in the photocatalytic production of H2O2. Therefore, we summarize the research achievements in this field in recent years. This review first briefly introduces the reaction pathway, detection techniques and evaluation metrics. Then, the recent advances in photocatalysts are highlighted. Furthermore, the existing challenges and possible solutions in this field are presented. At last, we look forward to the future development direction of this field. This review provides valuable insights and guidance for efficient photocatalytic H2O2 production. [ABSTRACT FROM AUTHOR]

Alkenylbenzene skeletons represent one of the most widely occurring structural motifs in pharmaceutical drugs, natural products, and advanced materials. The construction of alkenylbenzenes is promising through the use of a straightforward oxidative alkenylation protocol, particularly from unactivated alkenes. This is significant because unactivated alkenes are inexpensive raw materials that can be obtained in bulk quantities from petrochemical feedstocks and renewable resources. However, controlling the reactivity and regioselectivity of olefination with unbiased olefins remains a significant challenge, necessitating continuous efforts and potentially having a substantial impact on both organic synthesis and the industry. This review aims to provide an overview of the latest advances in regiocontrol strategies for oxidative alkenylation reactions with unactivated alkenes, which can be categorized into three types: 1) ligand‐promoted/accelerated reactions; 2) prefunctionalized olefins‐facilitated reactions; 3) directing group‐induced reactions. [ABSTRACT FROM AUTHOR]

Passerini polymerization using naturally occurring α-lipoic acid as a raw material yields polyamides with 1,2-dithiolane functional groups in a one-step reaction. The polyamide exhibits characteristics of an adaptable dynamically crosslinked network through reversible ring-opening reaction of 1,2-dithiolane, enabling self-healing, reusable strong adhesion, and regeneration through decrosslinking and re-crosslinking. [ABSTRACT FROM AUTHOR]

Hemicellulose extracted by alkali treatment is of interest because of the advantages of its intact sugar structure and high degree of polymerization. However, the hemicellulose extracted by alkali treatment contained more lignin fragments and the presence of a lignin–carbohydrate complex (LCC), which affected the isolation and purification of hemicellulose and its comprehensive utilization. Therefore, the evaluation of the LCC structure of different types of lignocellulosic resources is of great significance. In this study, the LCC structures of hardwoods and Gramineae were enriched in alkaline systems. Information on the composition, structural proportions, and connection patterns of LCC samples was discussed. The similarities and differences between the LCC structures of different units of raw materials were comparatively studied. The results indicated that the monosaccharide fractions were higher in the LCC of Gramineae compared to hardwoods. The composition of the lignin fraction was dominated by G and S units. The phenyl glycosidic (PhGlc) bond is the predominant LCC linkage under alkali-stabilized conditions. In addition, Gramineae PhGlc types are more numerous compared to hardwoods. The results of the study provide insights into the differences in the chemical composition and structural features of LCC in different plants and provide important guidance for the optimization of the process of purifying hemicellulose. [ABSTRACT FROM AUTHOR]

This paper presents the results of investigations into the pyrolysis of waste polypropylene in a laboratory fixed-bed batch reactor. The experiments were designed and verified in such a way as to allow the application of the response surface methodology (RSM) in the development of an empirical mathematical model that quantifies the impacts mentioned above. The influence of the mass of the raw material (50, 100, and 150 g) together with the reactor temperature (450, 475, and 500 °C) and the reaction time (45, 50 and 75 min) was examined. It has been shown that the mass of the raw material, i.e., the filling volume of the reactor, has a significant influence on the pyrolysis oil yield. This influence exceeds the influence of reactor temperature and reaction time. This was explained by observing the temperature change inside the reactor at three different spots at the bottom, middle, and top of the reactor. The recorded temperature diagrams show that, with greater masses of feedstock, local overheating occurs in the middle part of the reactor, which leads to the overcracking of volatile products and, from there, to an increased formation of non-condensable gases, i.e., a reduced yield of pyrolytic oil. [ABSTRACT FROM AUTHOR]

In this study, we synthesized a polymer hydrogel(PPNS), which features multiple hydrogen bonds through copolymerization, by using N -isopropylacrylamide, polyvinyl alcohol, and octadecyl polyoxyethylene ether acrylate (SGA 15) as raw materials. The PPNS hydrogel demonstrated outstanding high-resolution, repeatable recording capabilities, enabling reversible recording, encryption, and decryption of information using anhydrous ethanol as the inducer. Due to their responsive and dynamic nature of PPNS hydrogels are positions them as promising candidates for use as innovative information storage platforms. [Display omitted] Smart hydrogel materials, known for their sensitivity to external stimuli, exhibit a reversible dynamic response and find applications in diverse fields, particularly in information storage. Despite significant efforts in this domain, developing a hydrogel with high-resolution, repeatable recording, and robust information encryption/decryption capabilities still remains a challenge. In this study, we synthesized a polymer hydrogel, namely polyvinyl alcohol- n -isopropylacrylamide-octadecyl polyoxyethylene ether acrylate hydrogel (PPNS), which features multiple hydrogen bonds through copolymerization, by using N -isopropylacrylamide, polyvinyl alcohol, and octadecyl polyoxyethylene ether acrylate (SGA 15) as raw materials. The PPNS hydrogel demonstrated outstanding high-resolution, repeatable recording capabilities, enabling reversible recording, encryption, and decryption of information using anhydrous ethanol as the inducer. Varying the SGA 15 monomer concentration revealed that the PPNS-2% hydrogel, prepared with 2% SGA 15 , outperformed the other hydrogels in terms of information recording and encryption/decryption when immersed in anhydrous ethanol and deionized water. Furthermore, the PPNS-2% hydrogel exhibited the ability to undergo multiple information cycles while maintaining excellent mechanical properties even after 25 cycles. Notably, ethanol served as a specialized ink for inscribing different patterns on the hydrogel surface for information recording. The recorded information could be erased through water wiping or ethanol volatilization, enabling reversible information recording, encryption, and decryption. Due to their responsive and dynamic nature of PPNS hydrogels are positions them as promising candidates for use as innovative information storage platforms. [ABSTRACT FROM AUTHOR]

Currently, the stable, uniform, and highly efficient production of raw materials for pharmaceutical companies has received special attention. To meet these criteria and reduce harvesting pressure on the natural habitats of licorice (Glycyrrhiza glabra L.), cultivation of this valuable plant is inevitable. In the present study, to introduce the glycyrrhizic acid (GA)- and glabridin-rich genotypes from cultivated Iranian licorice, forty genotypes from eight high-potential wild populations were cultivated and evaluated under the same environmental conditions. The GA content varied from 5.00 ± 0.04 mg/g DW (TF2 genotype) to 23.13 ± 0.02 mg/g DW (I5 genotype). The highest and lowest glabridin content were found in the K2 (0.72 ± 0.021 mg/g DW) and M5 (0.02 ± 0.002 mg/g DW) genotypes, respectively. The rutin content in the leaves of the studied genotypes varied from 1.27 ± 0.02 mg/g DW in E4 to 3.24 ± 0.02 mg/g DW in BO5 genotypes. The genotypes from the Ilam population were characterized by higher vegetative growth and yield traits in the aerial parts and roots. The average root dry yield was 2.44 tons per hectare (t/ha) among the studied genotypes and a genotype from Ilam (I5) yielded the maximum value (3.08 ± 0.034 t/ha). The highest coefficient of variation among the genotypes was observed for leaf width (CV = 34.9%). The GA and glabridin-rich genotypes introduced in this study can be used in the future breeding programs to release new bred licorice cultivars. [ABSTRACT FROM AUTHOR]

Geopolymer materials, considered to be an alternative to Portland cement-based concretes, can be produced from various types of waste aluminosilicate raw materials. This article presents the results of research related to the use of diatomite as an additive in geopolymers. The results of testing geopolymer composites with 1%, 3%, and 5% additions of diatomite with a grain size of 0–0.063 mm after and without thermal treatment were presented. This article presents the physical properties of the diatomite additive, the morphology of diatomite particles SEMs, thermal analysis, and compressive strength test results. In this research, diatomite was treated as a substitute for both fly ash and metakaolin (replaced in amounts of 1 and 3%) and as a substitute for sand introduced as a filler (in this case, 5% of diatomite was added). As a result of this research, it was found that the addition of diatomite instead of the main geopolymerization precursors in amounts of 1 and 3% had a negative impact on the strength properties of geopolymers, as the compressive strength was reduced by up to 28%. The introduction of crushed diatomite instead of sand in an amount of 5% contributed to an increase in strength of up to 24%. [ABSTRACT FROM AUTHOR]

A crimping and pultruding forming process for truss rods using Carbon Fiber (CF)/Polyether–Ether–Ketone (PEEK) prepreg tape as the raw material is proposed to address the problem of continuous manufacturing of space trusses on orbit. The proposed process provides material rods for continuous truss manufacturing. Through numerical simulation and experimental verification, the effects of relevant parameters on the forming process are determined, an efficient method of rod curl pultrusion, in-rail, equal material forming is proposed, and the structural configuration of the rod curl pultrusion forming mold is determined. The equivalent macroscopic mechanical properties of unidirectional CF/PEEK prepreg strips are considered, and the rod-forming process is investigated. Rod samples with different process parameters are prepared, and several tests are conducted on them. The results show that the forming load pull is negatively correlated with the temperature at the same forming speed, and forming speed is positively correlated with the forming load pull at a certain temperature. Temperature and speed affect the surface quality of the rod, the density of the material filling, and the mechanical properties of the rod. The optimal forming process parameters are determined through numerical simulation and experimental verification. The developed molding technology has the advantages of high efficiency, low energy consumption, and high integration. It reduces manufacturing costs and improves manufacturing efficiency, so it can serve as a new and effective solution for the manufacturing of high-performance truss rods in the aerospace field. [ABSTRACT FROM AUTHOR]

Silica fly ash, Certyd aggregate, and an alkaline solution were used to produce lightweight geopolymer concretes. The compressive strength, water absorption, and bulk density results, along with SEM photos showing the structure of the obtained composite, were obtained. Tests conducted on the specifications of lightweight geopolymer concretes have revealed significant chemical interactions between the ash aggregate and the geopolymer mortar, particularly when the coarse aggregate surface has been pre-treated with an alkaline solution. A statistical analysis of the experimental data, which investigated the influence of three key variables on the compressive strength, water absorption, and bulk density of lightweight geopolymer concrete (LBG), identified the following factors as having the most substantial impact: the quantity of alkali used, the curing temperature, and the concentration of alkali in the mixture. The optimal test series exhibited a commendable compressive strength of 20.14 megapascals (MPa), accompanied by a water absorption rate of 14.72%, and a bulk density of 1486.6 kg per cubic meter (kg/m³). These findings underscore the importance of alkali content, curing temperature, and alkali concentration in tailoring the properties of lightweight geopolymer concrete to meet specific performance requirements. [ABSTRACT FROM AUTHOR]

The work presents a detailed analysis of the possibilities of the thermal processing of clay raw material granulates in a fluidized bed reactor powered by coal fuel. Potential customers of calcined granulates include the following: plants producing refractory materials for the steel industry, producers of refractory concrete, sanitaryware plants, tile plants, large-size tile plants, industry abrasives, chemicals, paints, paper, food and medical industries and others. The advantage of the presented fluid bed calcination technology is the possibility of the continuous operation of the reactor and the short time of the material in the bed, compared to the previously used methods of calcination in a shaft and rotary kiln, which lasts less than twenty minutes in the temperature range of 650–850 °C. During the experimental studies of calcination in the fluidized bed layer, the influence of the type of coal, its particle size and the mass share of coal in the feed mixture on the calcination process and the final product obtained was analysed. As a result of the conducted research, it was proven that solid fuels such as anthracite and steam coal type 31.2 (flaming) can be successfully used in the fluidized bed calcination process of clay materials. The key parameter determining the fluidized bed calcination process is the fuel particle distribution. [ABSTRACT FROM AUTHOR]

• Insights were gained regarding graphite recovery from spent lithium-ion batteries. • New information about LTO behavior in froth flotation was discovered. • Graphite recoveries, grades and kinetic data was measured. • The research discusses optimal recycling strategies for NMC-LTO-graphite mixtures. The growing electric vehicle industry has increased the demand for raw materials used in lithium-ion batteries (LIBs), raising concerns about material availability. Froth flotation has gained attention as a LIB recycling method, allowing the recovery of low value materials while preserving the chemical integrity of electrode materials. Furthermore, as new battery chemistries such as lithium titanate (LTO) are introduced into the market, strategies to treat mixed battery streams are needed. In this work, laboratory-scale flotation separation experiments were conducted on two model black mass samples: i) a mixture containing a single cathode (i.e., NMC811) and two anode species (i.e., LTO and graphite), simulating a mixed feedstock prior to hydrometallurgical treatment; and ii) a graphite-TiO 2 mixture to reflect the expected products after leaching. The results indicate that graphite can be recovered with > 98 % grade from NMC811-LTO-graphite mixtures. Additionally, it was found that flotation kinetics are dependent on the electrode particle species present in the suspension. In contrast, the flotation of graphite from TiO 2 resulted in a low grade product (<96 %) attributed to the significant entrainment of ultrafine TiO 2 particles. These results suggest that flotation of graphite should be preferably carried out before hydrometallurgical treatment of black mass. [ABSTRACT FROM AUTHOR]

The Jerusalem artichoke (Helianthus tuberosus) is a high-yield crop, and a great source of fermentable sugars, which gives the plant the potential to be used as raw material for economical fuel alcohol production. In this article, the authors focus on the technological aspect of the biofuel manufacturing process and its properties. First, the fuel alcohol manufacturing process is described, afterwards assessing its characteristics such as kinematic viscosity, density and octane number. The amount of fuel alcohol obtained from 10 kg of biomass equals to 0.85 L. Afterwards, the mixtures of gasoline and obtained fuel alcohol are prepared and studied. Optimal alcohol and gasoline mixtures are determined to obtain biofuels with octane ratings of 92, 95 and 98. The kinematic viscosity of obtained mixtures does not differ significantly from its values for pure gasoline. The obtained biofuel mixture with 25% alcohol content yielded a decrease of sulfur content by 38%, an increase of vaporized fuel amount by 17.5% at 70 °C and by 10.5% at a temperature of 100 °C, which improves engine startup time and ensures its stable operation in comparison to pure gasoline. The alcohol obtained can be successfully used as a high-octane additive for gasolines. [ABSTRACT FROM AUTHOR]

As a semiconductor material, g-C 3 N 4 has attracted attention with proficient charge storage and transfer characteristics. However, there is a limitation in its applications because of the low specific surface area and the small number of active sites associated with the bulk structure, and there is a lack of in-depth understanding of its optical properties. In this paper, we have discussed four different morphologies of g-C 3 N 4 , including bulk (B–CN), hexagonal hollow tubular (T-CN), alveolate (A-CN), and hollow spherical (S–CN) that have been prepared using the supramolecular self-assembly strategy. To examine the changes in morphology that affect the physiochemical and optical properties of the g-C 3 N 4. With the change in the ratio of the raw materials and reaction condition, the number of defects in g-C 3 N 4 represented by uncondensed NH 2 /-NH groups changes, thus inhibiting the recombination of photogenerated carriers. Meanwhile, the changes in morphology affect the microstructural composition of g-C 3 N 4 , which changes the energy band positions and fluorescence properties of the material. This work provides some valuable information on the morphological regulation of g-C 3 N 4 and how to modulate the morphology to change the properties of g-C 3 N 4. • The successful preparation of g-C 3 N 4 with different morphologies. • The successful regulation of defective sites represented by NH 2 /-NH groups. • The individual bandgap states of the material were altered by modulating the morphology of g-C 3 N 4. • The influence of the microstructure of g-C 3 N 4 on its optical properties is deeply understood. [ABSTRACT FROM AUTHOR]

The early strength of geopolymers (GPs) and their composites is higher, and the hardening speed is faster than that of ordinary cementitious materials. Due to their wide source of raw materials, low energy consumption in the production process, and lower emissions of pollutants, they are considered to have the most potential to replace ordinary Portland cement. However, similar to other inorganic materials, the GPs themselves have weak flexural and tensile strength and are sensitive to micro-cracks. Improving the toughness of GP materials can be achieved by adding an appropriate amount of fiber materials into the matrix. The use of discrete staple fibers shows great potential in improving the toughness of GPs. Sisal is a natural fiber that is reproducible and easy to obtain. Due to its good mechanical properties, low cost, and low carbon energy usage, sisal fiber (SF) is a GP composite reinforcement with potential development. In this paper, the research progress on the effect of SF on the properties of GP composites in recent decades is reviewed. It mainly includes the chemical composition and physical properties of SFs, the preparation technology of sisal-reinforced geopolymers (SFRGs), the microstructure analysis of the interface of SFs and the GP matrix, and the macroscopic mechanical properties of SFRGs. The properties of SFs make them have good bonding properties with the GP matrix. The addition of SFs can improve the flexural strength and tensile strength of GP composites, and SFRGs have good engineering application prospects. [ABSTRACT FROM AUTHOR]