Raw Material Costs Research Articles

Improvement of the functional layouts of multifunctional soil-cultivating sowing units

BACKGROUND: With the technology evolution, the use of combined machines and units has become more in demand. From the numerous studies that were carried out during the operation of machines of this type, it can be seen that the cost of raw materials and financial costs have been significantly reduced, and the number of other advantages has been identified as well. AIM: Improvement of the functional layouts of multifunctional tillage sowing units for a more optimal combination of structural layouts and parameters of its use. METHODS: Engineers use the method of changing working bodies designed as layouts aiming to turn the machines into the modules capable of performing various types of operations based on working conditions. Thanks to this method, sets of individual working bodies and combinations are prepared for any kind of conditions (soil, climate, etc.). In addition to the advantages, this system has a number of disadvantages. One of these is that at the factory-built modules that are part of the original basis of the unit cannot be fully adapted to environmental conditions and economic factors of production. In this regard, combination of structural layouts and selection of the necessary parameters become problem causing. It is difficult to choose necessary parameters that are capable of ensuring minimal losses and adjusting the unit to the necessary operating mode. The objects of study are the devices and production processes, the main task of which is performing tillage and sowing operations. The practical value of this study presented in the form of: building the algorithm capable of structuring the analysis and synthesis of the structural layout of the tillage-sowing unit to find the working links for various types of unit functions; finding the methods and improved combinations of working bodies, comparison of similar mechanical analogues with the original properties of systems. RESULTS: When studying the studies of Wilde, who gave a description of the combined units, as well as the studies of Runchev, who determined the generalization of the combined machines, the relevant typology of agricultural machinery was developed. In this typology, one of the most important characteristics is multifunctionality, which has developed from the need for the versatility of units and the compilation of combinations of several units. The developed technology contains a number of characteristics that are fundamental for the choice of agricultural machinery. CONCLUSION: As a result of the study, it was determined at which velocity of the unit the system is balanced.

Nano ZnO modified amorphous carbon materials enabling long-cycle performance and high-capacity for lithium/sodium-ion batteries

Zinc-modified carbon materials exhibit high specific capacity, good safety, and low self-discharge, making them promising anode materials for lithium-ion and sodium-ion batteries. However, the high cost of raw materials, complex fabrication processes, and limited cycle life remain significant challenges to their further development. In this study, we elucidated a two-step process, simple in technique and suitable for large-scale production, for in-situ zinc modification of amorphous carbon. The synthesized carbon material exhibited superior reversible specific capacity (maintaining 780.27 mAh·g−1 capacity after 80 cycles at 50 mA·g−1 current density), high cycling stability (maintaining Coulombic efficiency at 100.06 % after 15,000 cycles at 10 A·g−1 current density), and good application value (achieving a capacity of 89.67 mAh·g−1 after 1000 cycles at 200 mA·g−1 current density for the assembled MFAC-Zn||NVP full cell). Through our investigation, we discovered that Nano ZnO not only directly participate in electrochemical reactions but also effectively improve the microstructure of amorphous carbon, increasing its three-dimensional axial stacking and providing more reaction sites. The enrichment of open pores significantly enhances the diffusion efficiency of ions within the carbon-based matrix. The superior diffusion ability of alkali metal-ion in the electrode is the reason for the excellent electrochemical performance of Zinc-modified amorphous carbon. Moreover, the incorporation of Nano ZnO aids in the formation of a robust and thin SEI layer. This significantly enhances the stability of the electrode materials during cycling and improves charge transfer efficiency during the charge-discharge process. Our study provides a new strategy for adjusting the internal microstructure of amorphous carbon materials to achieve high-performance lithium/sodium storage.

Exceptional tensile ductility and strength of a BCC structure CLAM steel with lamellar grains at 77 kelvin

The low-temperature tensile brittleness of body-centered cubic (BCC) metals and alloys can seriously compromise their service applications. In this study, we prepared a BCC structured China low activation martensitic steel (CLAM) steel with lamellar grains by regulating the rolling and heat-treatment processes, successfully reversing the decreasing trend of ductility in the steel with decrease in temperature. Compared with current face-centered cubic (FCC) structural steels and high-entropy alloys, the lamellar grained CLAM steel exhibits an excellent synergy of strength and ductility at 77K, but with lower raw material costs. The superior low temperature ductility of the lamellar grained steel can be attributed to an increase in grain strength at low temperatures which promotes the propagation of layered tearing cracks; this in turn leads to a significant increase in the necking area of the steel, thereby compensating for the decrease in ductility. We conclude that our lamellar grain structures can be utilized to significantly enhance the low-temperature tensile ductility of BCC metals and alloys, thereby expanding their service range to cryogenic temperatures.

Area-based composition predictions of materials fabricated using simultaneous wire-powder-directed energy deposition

Functionally graded materials are an emergent method for designing components with programmable site-specific material properties. These materials are typically fabricated using metal additive manufacturing tools by simultaneously feeding multiple wire and/or powder feedstocks at various rates to achieve spatial composition change. The wire-powder-directed energy deposition (WP-DED) technique is of particular interest for many functionally graded material applications by balancing the low raw materials cost of wire with the high resolution of powder. However, feeding wire and powder are inherently different processes since all extruded wire enters the melt pool, while much of the blown powder is scattered, which makes determining the composition of the build challenging. In this study, we devise a simple area-based measurement method for estimating the composition of WP-DED structures. WP-DED single beads are printed using 309L stainless steel wire and commercially pure Fe powder at five wire feed rates (0.5, 0.75, 1.00, 1.25, 1.50 mm/mm) and five powder feed rates (2, 4, 6, 8, 10 rpm). Characteristic defects including interface gaps and macrosegregation (lack of mixing) tendencies are examined. High powder feed rates (8, 10 rpm) result in interface gaps at all wire feed rates, but smooth deposition and complete mixing is achieved at low powder feed rates, particularly with lower wire feed rates as well. The area-based composition measurement method is within ±20% of energy dispersive x-ray spectroscopy measurements for all samples, showing its effectiveness as a rapid composition estimate for WP-DED materials development.

Fluorine-Free Cycloaliphatic Epoxy-Based Siloxane Nanohybrid Binder with High Polar Hydroxyl Group Content Enabling LiFePO4-Type Battery with High Electrochemical Performance and Stability.

LiFePO4-type (LFP) batteries have attracted significant attention in most battery manufacturing industries due to their long lifespan, high-temperature safety, and low cost of raw materials. However, as an active material, LFP still suffers from several intrinsic drawbacks, including poor conductivity, a low Li+ diffusion coefficient, low capacity, and a lack of electrochemical stability, primarily due to conventional fluorine-based binders. Here, we report a simple yet effective approach to developing a fluorine-free binder based on a robust cycloaliphatic epoxy-based siloxane nanohybrid material (CES) to achieve high electrochemical stability in LFP batteries. The high content of silanol moieties in CES induces a strong affinity for the active material and conductive agent, significantly improving rheological (thixotropy) and mechanical (adhesion and cohesion) properties, which enable the formation of a uniformly coated electrode. As a result, we achieved superior electrochemical performance and stability in CES-applied electrodes compared to those with conventional fluorine-based binders. We investigate the reasons behind the contribution of CES to the electrochemical stability of LFP batteries through various analyses. The high thermal and oxidation stability of CES effectively prevents degradation of LFP-based active materials. Our binder development strategy offers a significant breakthrough in replacing conventional fluorine-based binders, advancing the development of high-performance and stable secondary batteries.

Fusarium verticillioides pigment: production, response surface optimization, gamma irradiation and encapsulation studies

BackgroundNatural pigments are becoming more significant because of the rising cost of raw materials, pollution, and the complexity of synthetic pigments. Compared to synthetic pigments, natural pigments exhibit antimicrobial properties and is less allergic. Pigments from microbial sources could easily be obtained in an inexpensive culture media, produced in high yields, and microbes are capable of producing different colored pigments. Searching for new sources for natural pigments to replace synthetic ones in food applications has become an urgent necessity, but the instability of these compounds is sometimes considered one of the obstacles that reduce their application. Encapsulation provides an ideal solution for natural dye protection through a controlled release strategy. Thus, this study aims at isolation of several soil fungi and subsequent screening their pigment production ability. The chosen pigment-producing fungal strain underwent full identification. The produced pigment was extracted with ethyl acetate and estimated spectrophotometrically. As there is a necessity to obtain a high pigment yield for efficient industrial application, the best production medium was tested, optimum conditions for maximum dye production were also investigated through the response surface methodology, and gamma irradiation was also employed to enhance the fungal productivity. Encapsulation of the produced pigment into chitosan microsphere was tested. The pigment release under different pH conditions was also investigated.ResultsA new strain, Fusarium verticillioides AUMC 15934 was chosen and identified for a violet pigment production process. Out of four different media studied, the tested strain grew well on potato dextrose broth medium. Optimum conditions are initial medium pH 8, 25 °C-incubation temperature, and for 15-day incubation period under shaking state. Moreover, a 400 Gy irradiation dose enhanced the pigment production. Chitosan microsphere loaded by the pigment was successfully prepared and characterized by infrared spectroscopy and scanning electron microscopy.ConclusionThis irradiated Fusarium strain provides a more economically favorable source for production of a natural violet dye with an optimum productivity, enhanced yield, and improved properties (such as, enhanced stability, controlled release, and bioaccessibility) by encapsulation with chitosan for efficient application in food industry.

Evaluating Financial Performance in the Indian Food Sector: A TOPSIS Approach to Company Assessment

When evaluating financial performance, industry-specific elements that have an influence on the food business are taken into account, including raw material costs, pricing dynamics, the competitive environment, regulatory environment, and consumer trends. When assessing a company's general health and future prospects, it is important to take these elements into account because they have an impact on its financial performance Over the years, India's food business has undergone substantial development and change, driven by factors including shifting customer tastes, urbanisation, and rising disposable income. The industry includes a number of subsectors, including restaurants, processed food, drinks, dairy products, and confectionery. Over the years, India's food business has undergone substantial development and change, driven by factors including shifting customer tastes, urbanisation, and rising disposable income. The industry includes a number of subsectors, including restaurants, processed food, drinks, dairy products, and confectionery. Investment Decisions: Evaluating the financial performance of food sector firms enables investors to make wise investment choices. Risk management: It's crucial to comprehend the financial status of businesses in the food sector. Industry Competitiveness: Analysing financial performance sheds light on the Indian food industry's competitive environment Government agencies and regulatory organisations can use financial performance assessments to develop policies and regulations that support the expansion and sustainability of the food sector. Sector Analysis: Evaluations of financial performance help with a more comprehensive study of the Indian food business. Investment Decisions: Evaluating the financial performance of food sector firms enables investors to make wise investment choices. Risk management: It's crucial to comprehend the financial status of businesses in the food sector. Industry Competitiveness: Analysing financial performance sheds light on the Indian food industry's competitive environment Government agencies and regulatory organisations can use financial performance assessments to develop policies and regulations that support the expansion and sustainability of the food sector. Sector Analysis: Evaluations of financial performance help with a more comprehensive study of the Indian food business. Alternative Parameter taken as Company 1, Company 2, Company 3, Company 4, Company 5, Company 6. Evaluation Parameter Net Profit Margin, Current Ratio, Debt Ratio, Debt to Equity. After doing topsis analysis company 2 has ranked 1 company 2 has ranked 6. TOPSIS method provides a systematic and comprehensive approach for evaluating alternatives based on multiple criteria. It considers both the positive and negative aspects of each alternative and helps decision makers in selecting the most suitable option based on their preferences and objectives.

Apparel Supply Chain Management and Practice under the Perspective of Sustainable Development

Abstract: This study explores the challenges faced by the apparel industry and the means of attaining sustainable development via effective supply chain management amidst the backdrop of global economic integration and the evolving information technology landscape.Firstly, the current situation of the apparel industry is analyzed, including factors such as the increase in consumers' personalized demands, the increasingly fierce competition, the rising costs of labor and raw materials, and the growing consciousness of environmental preservation. The development status and problems of apparel supply chain management are then analyzed, including the excessively long supply chain, the lack of flexibility and adaptability in management, the opacity of information, the lack of a supplier evaluation system, and the neglect of sustainable development by enterprises. It further discusses achieving sustainable development in the apparel industry, including reducing water consumption and pollution, addressing the adverse consequences arising from the rapid turnover of fashion trends, promoting the construction of a circular supply chain, etc. Corresponding solutions are proposed. Finally, this study concludes how supply chain management and sustainable development practices can inject new vitality into apparel enterprises and achieve the industry's sustainable development goals.

Technological Aspects of using 3D Printing Software in Construction

The relevance of introducing additive technologies of 3D printing in construction is to decrease the technological cycle of construction, and minimize expenditure and material costs, while reducing the duration of the development planning process and execution, eliminating inaccuracies and defects, as well as optimizing and automate the process. The technological aspect of 3D printing lies in the optimal selection of parameters based on the created 3D model using effective software. The purpose of the study is to determine the quality indicators of bricks obtained by 3D printing from special concrete. The approach to investigating this matter is rooted in ascertaining the compressive strength of concrete through non-invasive testing techniques, gauging the density of concrete using measurement methods, and validating the efficacy of integrating 3D printing technologies in construction by the method of comparative analysis. The effectiveness of introducing additive technologies of 3D printing was proven drawing upon quality indicators of concrete obtained on a 3D printer which meets all the requirements necessary for its implementation in the construction field. The selected characteristics of concrete compressive strength are fundamental to the basics of selecting a brand of concrete to be utilized in construction. The selected software demonstrated the capacity to generate flawless 3D designs. The result of the study shows a significant reduction in the number of workers involved in the construction process by 38–45%, depending on the chosen method of using 3D printing; a decrease of construction time by 33–42% when printing individual elements, blocks used in production, and by 61–72% when using a printer directly on the construction site; reduction of raw materials costs by 14–28%; as well as reduction of construction downtime by 25%. The results obtained indicate the need to develop and enhance progressive additive technologies for 3D printing in construction.

A novel integrated prediction method using adaptive mode decomposition, attention mechanism and deep learning for coking products prices

Accurate prediction of coking product prices is crucial for enhancing production efficiency, cost optimization, and profit maximization in smart coking facilities. To address the volatility caused by nonlinear factors such as raw material costs, substitutes, macroeconomic indicators, sudden events, policy changes, and market behaviors, we propose a novel integrated prediction method for coking product price prediction. This method combines Complete Ensemble Empirical Mode Decomposition with Adaptive Noise (CEEMDAN) for signal decomposition, Bidirectional Encoder Representations from Transformers (BERT) for natural language processing, attention mechanisms (AT) to weigh feature importance, and an ensemble of Bidirectional Gated Recurrent Unit, Bidirectional Long Short-Term Memory, and Gated Recurrent Unit, abbreviated BBG, for robust feature extraction. We design a feature selection strategy to avoid data leakage and improve the predictive ability of the model, and describe a method to maintain textual data information integrity when combining data from different sources. Experimental results on coke and methanol datasets show that our approach retains multi-source text richness improves predictive capability, and outperforms other state-of-the-art methods, providing an effective tool for developing smart coke plants.

Separator‐Supported Electrode Configuration for Ultra‐High Energy Density Lithium Secondary Battery

AbstractSignificant efforts are being made to develop high‐performance battery materials, particularly active materials. However, material‐dependent strategies for increasing energy density face challenges such as raw material costs and supply limitations, reducing their versatility to some extent. In this regard, the development of efficient battery designs can be a universal approach to increasing the energy density of lithium‐ion batteries with relatively low dependence on material properties. Herein, a novel configuration of an electrode‐separator assembly is presented, where the electrode layer is directly coated on the separator, to realize lightweight lithium‐ion batteries by removing heavy current collectors. Even on the hydrophobic separator, a poly(vinyl alcohol) binder enables uniform and scalable coating of aqueous electrode slurries through molecular interactions with the separator surface. Moreover, carbon nanotubes are utilized to reinforce the electronic conduction of the electrode, providing consistent electronic pathways regardless of SEI formation. Furthermore, owing to the superior permeability of liquid electrolytes through this electrode‐separator assembly, a multilayered electrode‐separator assembly can be suggested to further increase energy density when combined with a lithium metal anode. This lithium metal battery can achieve an areal capacity of ≈30 mAh cm−2 and an enhanced energy density of over 20% compared to conventional battery configurations.

BioTRY: A Comprehensive Knowledge Base for Titer, Rate, and Yield of Biosynthesis.

Synthetic biology is rapidly evolving into a data-intensive science that increasingly relies on massive data sets; one of its applications is the evaluation of the economic viability of fermentation processes. However, the key economic indicators, namely titer, rate, and yield (TRY), which respectively reflect the downstream processing, reactor size, and raw material costs, are not well captured in bioinformatics databases. In this paper, we present BioTRY, an intuitive and user-friendly tool that contains >5,000 biochemicals and >3,800 strains, along with over 52,000 corresponding TRY entries with original references. It is freely available at http://www.synbiohealth.cn/biotry. To our knowledge, BioTRY is the first available database on biosynthesis TRY data from original research. We anticipate that BioTRY will become a useful tool that aids researchers and decision-makers in understanding the current development state of biosynthesis and allows them to foresee potential prospects and applications for biosynthesis.

Impact of Cost Structure on Indonesia Food Industry Value Added

The food industry is a consistently growing sector, even in challenging economic conditions, driven by population growth and increased demand. Recognizing its importance, the Indonesian government has identified the food and beverage industry as a key sector in its Industry 4.0 roadmap. However, challenges such as reliance on imported raw materials and high labor absorption rates persist. This study analyzes the impact of cost structure on the value-added in Indonesia's food industry from 2017 to 2021, using data from Indonesia Statistics on large and medium industries. The Panel Data Regression results reveal that raw material costs and fixed capital costs positively and significantly affect value-added. These findings suggest that effective cost management, innovation, and the use of advanced technology are crucial for optimizing value-added in this sector.

Purification of T7 RNA polymerase for large scale production of mRNA vaccines and therapeutics

The COVID-19 Pandemic has revolutionized the field of mRNA vaccine technology, highlighting its utility and rapidly expanding potential, propelling it to the forefront of future vaccines & therapeutics for cryptic diseases. T7 RNA Polymerase (T7 RNAP) is a high-fidelity enzyme used for the synthesis of single-stranded mRNA from DNA templates using In vitro transcription (IVT). T7 RNAP is now the mainstay for the development of mRNA vaccines and therapeutics, accounting for 34 % of the overall raw material cost for mRNA manufacturing. Although small-scale purification processes for T7 RNAP exist, scalable process platforms and comprehensive analytical characterization are still lacking. Moreover, to address global raw material supply chain issues and to facilitate the efficient and large-scale production of mRNA vaccines & therapeutics, here we report a three-step purification process platform, yielding ∼ 85–100 mg/L of T7 RNAP from E. coli fermentation harvest. Also, to demonstrate its high-level purity and structural integrity, we have characterized it using orthogonal analytical techniques. Furthermore, when evaluated in an IVT system, this highly pure T7 RNAP showed activity that was comparable to the commercial T7 RNAP in producing integral RNA (10 kb) from a linearized plasmid DNA template. Collectively, these findings establish a purification process platform for the commercial production of T7 RNAP enzyme to support the future development of mRNA-based vaccines and therapeutics.

Lightweighting an automotive fuel tank through formability analysis

For lightweighting automotive sheet metal parts, it is important to use the right grade/material with the minimum possible initial blank thickness in the forming processes. Fuel tank is one of the most critical sheet metal parts in automobiles due to its complex shape and large depth. In this work, a simulation-based approach has been employed to study the feasibility of lightweighting an automotive fuel tank (for two wheelers) by reducing blank thickness and changing steel grade. Formability analysis has been carried out using numerical simulations of a 0.8 mm thick sheet of Extra Deep Drawing (EDD) steel which is being used to manufacture the fuel tanks. Simulations have been performed to find out the minimum initial sheet thickness which can be formed successfully without failure or excessive thinning. From the predictions of formability, thinning, and strain distributions in the formed parts, it has been found that the weight of the part can be reduced by 12.5% by reducing the initial thickness from 0.80 to 0.70 mm. To reduce the thickness further, simulations have also been carried out by changing the grade from EDD steel to Interstitial Free (IF) steel which has superior drawability than EDD steel. It has been found that the blank thickness can be further reduced to 0.65 mm in the case of IF steel which is expected to result in 19.0% reduction in the weight of the component. The predictions have been validated by the actual press trials in the industry with reduced sheet thickness. The predicted strain distribution and thinning in the formed parts have also been validated with the experimental press trails. In addition to the weight reduction, the proposed change in thickness and grade would lead to a reduction of 16.5% and 4.0%, respectively, in the raw material cost of the fuel tank.

A joint economic evaluation and FP2O techno-economic resilience approach for evaluation of suspension PVC production

The production of polyvinyl chloride (PVC) involves obtaining a thermoplastic polymer from vinyl chloride monomer (VCM) and ethylene, primarily through the suspension method. This process is vital for manufacturing various products, such as pipes and coatings. However, its high-energy consumption necessitates economic evaluations to assess feasibility. In this work, a dual approach is proposed: a Feedstock-Processing-Product-Operation (FP2O) based techno-economic resilience analysis via sensitivity analysis alongside economic evaluation. The study evaluated a PVC production process with a capacity of 518,400 t/y of VCM over a 15-year plant lifespan. The techno-economic assessment revealed a Total Capital Investment of $609, 882, 203, a Payback Period of 4.22 years, and a Return on Investment of 14.38 %. Positive Net Present Value and a cost/benefit ratio >1 indicate the plant's installation under proposed conditions is favorable. Additionally, the technical-economic resilience analysis identified the process's response to changes in PVC price, raw material costs, and production capacity, guiding improvement actions pre- and post-plant assembly.

An Analytical Study on Global Automotive Price Trends and Influencing Factors

This study analyzes global automotive price trends and the key factors influencing these trends from 2018 to 2023. Using a mixed-method approach, it examines historical data, market conditions, and future projections. The findings highlight the impact of technological advancements, economic conditions, government policies, and changing consumer preferences on automotive prices. The study reveals a consistent increase in electric vehicle (EV) adoption, driven by government incentives and environmental awareness, alongside rising new car prices influenced by higher production costs and advanced features. Inflation and raw material costs have significantly impacted vehicle prices, while government subsidies have facilitated the broader acceptance of EVs. The results underscore the importance of understanding these dynamics for stakeholders to navigate the automotive market effectively. Future research should explore the long-term effects of emerging technologies and evolving regulations on automotive prices. Insights from this study are useful for manufacturers, policymakers, and consumers to make informed decisions in a rapidly evolving industry.

Interface misfit of conventionally milled and novel hybrid full-arch implant-supported titanium frameworks

ObjectiveA hybrid manufacturing technique that combines selective laser melting (SLM) and computer numerical control (CNC) has been developed for the fabrication of implant-platform/framework interfaces (PFIs) for mandibular and maxillary full-arch implant-supported titanium frameworks. The aim of this study was to compare the discrepancies in specimens fabricated using the hybrid technique (termed SLM/m hereafter) with those in specimens fabricated by conventional CNC milling.Materials and methodsBased on a mandibular four-PFI CAD model and a maxillary six-PFI CAD model, four groups of titanium frameworks (eight per group, totaling 32) were fabricated according to the fabrication technique (SLM/m or milling) and number of PFIs (four or six). The frameworks were scanned by a structured light scanner and aligned with the CAD model in Geomagic Control X. Discrepancy was defined as the difference between the PFIs of the scanned framework and those of the CAD model. Discrepancies were measured and evaluated by multilevel analysis using a mixed-effects model (α = 0.05), followed by independent samples t-tests (α = 0.0125). Furthermore, the manufacturing times and raw-material costs were recorded and compared.ResultsThe maximum discrepancy values for the four-PFI and six-PFI hybrid frameworks were 52.2 and 64.3 μm, respectively. Multilevel analysis revealed that the fabrication technique and the number of PFIs had no significant effect on the discrepancy value. However, a significant interaction between the two factors was observed (P = 0.020). The discrepancies for the four-PFI hybrid frameworks were significantly lower than those for the four-PFI milled frameworks (P = 0.001). No significant difference in discrepancies between the six-PFI hybrid frameworks and six-PFI milled frameworks was observed (P = 0.697). Furthermore, the hybrid frameworks required only 11% of the raw materials and 25% of the milling time required for the conventionally milled frameworks.ConclusionSLM/m hybrid frameworks are viable, accurate alternatives to CNC-milled frameworks, with the added benefit of substantial cost reduction.

Study on the structure and property of metallocene ethylene/1-heptene and ethylene/1-octene copolymers

Polyolefin elastomers are typically copolymers of ethylene with 1-butene, 1-hexene, or 1-octene. Other types of comonomers have not been widely applied industrially. The cost of 1-heptene obtained from Fischer-Tropsch synthesis is only half that of 1-octene, making it a viable economical substitute. This work utilized 1-heptene from Fischer-Tropsch synthesis and 1-octene from ethylene oligomerization as research subjects. Eight metallocene POEs based on 1-heptene and 1-octene were synthesized using Me2Si(C5Me4)(N t Bu)]TiCl2 (Ti-CGC) catalyst. The copolymers’ molecular structures and physical properties were characterized using HT-GPC, Temperature Rising Elution Fractionation (TREF),13C-NMR, DSC, Melt Index (MI), and Tensile tests. Compared to 1-heptene, 1-octene more effectively reduces the melting point and crystallinity, while 1-heptene’s stronger comonomer insertion capability facilitates the production of copolymers with higher comonomer content. Similar ternary sequence distributions and molecular dynamics indicate that ethylene/1-heptene and ethylene/1-octene copolymers possess comparable chain microstructures. Both ethylene/1-heptene copolymers and ethylene/1-octene copolymers exhibit excellent toughness and mechanical properties. Although the activity and insertion capacity of ethylene and 1-heptene decrease at low comonomer concentrations, they significantly improve at higher comonomer concentrations. Thus, Fischer-Tropsch synthesis of metallocene ethylene/1-heptene copolymers can effectively reduce raw material costs and be a cost-effective alternative to ethylene/1-octene copolymers.

Performance evaluation of bio-oil and high rubber content modified asphalt: More effective waste utilization

In this study, the bio-oil was used to reduce the viscosity and preparation temperature of high content of rubber-modified asphalt. The high rubber content modified bio-asphalt (RMBA) was prepared, the rubber and bio-oil contents were 20 %-30 % and 5 %-15 % (mass ratio of neat asphalt), respectively. The viscosity, temperature sweep (TS), frequency sweep (FS), multi-stress creep recovery (MSCR), and bending beam rheometer (BBR) tests were performed to assess the properties of RMBA. The Fourier Transform infrared spectroscopy (FTIR), Fluorescence microscopy (FM), and Scanning electron microscope (SEM) tests were conducted to explore the microscopic morphology of RMBA. Besides, the economic analysis and life cycle assessment (LCA) were assessed. Bio-oil contributed to the viscosity-reduction of the RMBA. When the rubber content was 30 %, the viscosity decreased by 48.16 % with a bio-oil content of 15 %. The temperature and frequency sensitivity of RMBA were lower than neat asphalt. Rubber improved the creep recovery and anti-rutting deformation behavior for bio-asphalt. The absorption peaks appeared at 1010 and 1038 cm−1, which represented the SO function group. The rubber did not absorb enough bio-oil for solubilization. This resulted in the functional group of SO appeared in 30 %+B-10 % and R-30 %+B-15 %. FM and SEM test results indicated that the rubber in RMBA exists in different states: undissolved rubber and dissolved rubber. The high content rubber could be partially dissolved in bio-asphalt and retained its elastic properties. The dissolved rubber particles exhibited a large crosslinked network structure. The raw material cost of RMBA decreased significantly with the rise of rubber and bio-oil contents. The reasonable application of waste rubber is beneficial to the alleviation of black pollution. The efficient application of rubber and bio-oil could contribute to the development of waste utilization and green transportation.