abstract This study presents an innovative crude oil heating technology by introducing environmentally friendly solar energy into the petroleum industry. By integrating novel combination methods into traditional crude oil heating systems, a versatile and efficient crude oil heating system has been formed. The system was implemented in a refinery and its thermodynamic and economic performance was analyzed. The thermodynamic analysis, employing the exergy analysis method, reveals that among the considered parameters, compressor pressure ratio and Rankine cycle fluid flow rate exert the most significant influence on system efficiency. Overall, the system achieves energy efficiency, exergy efficiency, and waste heat recovery efficiency of 75.99%, 74.13%, and 31.21%, respectively. Within the system, solar collectors, TES tank, and compressor exhibit the highest exergy destruction rates, while pumps demonstrate the lowest exergy destruction rate. The economic analysis, using the annualized cost method, revealed that electricity prices have a significant impact on the economic performance of the system. The variation in system economic parameters is related to the annualized operating cost of the system. The system generates a net annual benefit of 0.591 million US$, with a 4.124-year investment return period. Moreover, Sensitivity analysis explores various factors affecting the crude oil heating system’s performance. industry systems formed analyzed method Overall 7599 75 99 75.99% 7413 74 13 74.13% 3121 31 21 31.21% respectively collectors tank rates 0591 0 591 0.59 US US$ 4.124year 4124year year 4.124 4 124 period Moreover s 759 7 9 75.99 741 1 74.13 312 3 2 31.21 059 59 0.5 124year 4124 4.12 12 75.9 74.1 31.2 05 5 0. 412 4.1 75. 74. 31. 41 4.

The study aims to optimize machining parameters for turning SAE 8822 Alloy steel under green machining (without coolant), using a CNC turning machine with a carbide tool. The controlled factors are spindle speed (A), feed rate (B), and depth of cut (C), with roughness (Ra) as the response variable. The experimental runs are conducted using an L9 Orthogonal Array (OA). Orthogonal arrays are used to efficiently explore the parameter space with a relatively small number of experimental runs while maintaining statistical validity. The impact of the machining parameters on the roughness is interpreted using Analysis of Variance (ANOVA). ANOVA is a statistical technique that helps identify the significance of each parameter and their interactions on the response variable. The result indicated that variation of A between 1500 rpm to 2000 rpm resulted in a significant increase in Ra. Similarly, the effect of B and C contributed towards huge variations in Ra. The optimal values of 1500 rpm for A, 0.5 mm/rev for B, and 1 mm for C are identified as the most favorable combination for achieving the desired Ra. Achieving a minimum Ra of 0.04 microns indicate a very high-quality surface, which may be desirable in precision engineering applications. The analysis shows that the C and B have the highest influence followed by A on Ra. 882 without coolant, coolant , coolant) tool (A) (B) C, (C) (Ra variable L OA. OA . (OA) validity ANOVA. (ANOVA) 150 200 Similarly 05 0 5 0. mmrev rev 004 04 0.0 highquality high quality surface applications 88 (A (B (C (OA (ANOVA 15 20 00 8 2

ABSTRACT The objective of this work was to evaluate the thixoformability of the Al4Si2.5Cu alloy under two different production routes: the techniques via grain refining and via electromagnetic stirring, ranging from obtaining the alloy to its microstructural and mechanical characterization after the thixoforging process in a mechanical eccentric press. The alloy was subjected to globularization heat treatments promoting the globularization of the primary phase particles for 0s and 210s in the 45% solid fraction and the thixoforged sequence. The thixoforging tests showed that the necessary force to close the die is practically constant, regardless of the globularization time, remaining around 70 kN, using less than a third of the press capacity. Regarding its morphology for both production routes, it presented a globular morphology for both heat treatment times. The thixoforged parts showed good formability, filling the entire matrix and reproducing its geometry, in addition to presenting good mechanical properties through tensile tests, that is, the limit value of tensile strength, especially when using the production route via electromagnetic stirring, presented values close to at 200 MPa. It demonstrates that the alloy becomes suitable for thixoforming processes. Al4Si25Cu AlSiCu Al4Si2 5Cu Al Si Cu routes stirring s 45 sequence constant time 7 kN capacity times formability geometry strength 20 MPa processes AlSi Al4Si 4 2

RESUMO O objetivo deste trabalho foi avaliar a tixoconformabilidade da liga Al4Si2.5Cu sob duas diferentes rotas de produção: técnica via refino de grão e via agitação eletromagnética, abrangendo desde a obtenção da liga até sua caracterização microestrutural e mecânica após o processo de tixoforjamento em uma prensa excêntrica mecânica. A liga foi submetida a tratamentos térmicos de globularização que promovem a globularização das partículas de fase primária pelos tempos de 0s e 210s na fração sólida de 45% e na sequencia tixoforjada. Os ensaios de tixoforjamento mostraram que a força necessária de fechamento da matriz é praticamente constante, independentemente do tempo de globularização, ficando em torno de 70 kN, utilizando menos de um terço da capacidade da prensa. Com relação a sua morfologia para ambas as rotas de produção, a mesma apresentou morfologia globular para ambos os tempos de tratamento térmico. As peças tixoforjadas apresentaram boa conformabilidade preenchendo toda a matriz e reproduzindo sua geometria, além de apresentar boas propriedades mecânicas nos ensaios de tração, ou seja, o valor limite de resistência à tração principalmente quando utilizado a rota de produção via agitação eletromagnética apresentou valores próximos a 200 MPa. Demonstrando que a liga torna-se propicia aos processos de tixoconformação. Al4Si25Cu AlSiCu Al4Si2 5Cu Al Si Cu s 45 tixoforjada constante 7 kN térmico geometria seja 20 MPa tornase torna se tixoconformação AlSi Al4Si 4 2

ABSTRACT Coal gangue occupies substantial land resources. Using coal gangue as reinforcement fill material is an effective utilization method. The characteristics of the soil-reinforcement interface influence the safety and stability. Large-scale direct shear tests were conducted to study the interface characteristics of coal gangue with polypropylene woven geotextile, welded steel-plastic geogrid, and high-density polyethylene uniaxial geogrid. The tests revealed that the shear stress-shear displacement relationship is nonlinear and positively correlated with normal stress, with the breakage of burnt coal gangue particles observed during the process. The maximum shear stress and shear strength index of the interface for the three geosynthetics reinforced coal gangue are in the order of uniaxial high-density polyethylene (HDPE) geogrid showing the highest reinforcement strength, followed by the welded steel-plastic geogrid, with the polypropylene woven geotextile having the lowest strength. After HDPE geogrid reinforcement, interface friction angle slightly changes, but cohesion significantly increases, with an increase of 1156.9%. Considering the interface interactions, among the three geosynthetic materials, HDPE geogrid exhibits the most effective reinforcement effect on coal gangue, followed by the welded steel-plastic geogrid. The geotextile shows the least effectiveness in reinforcing burnt coal gangue. For reinforced coal gangue projects, HDPE geogrid is recommended as the reinforcing material. resources method soilreinforcement soil stability Largescale Large scale steelplastic steel plastic highdensity high density stressshear process (HDPE changes increases 11569 1156 9 1156.9% interactions materials projects 115 1156.9 11 1156. 1

This study delves into the utilization of advanced materials to enhance the mechanical characteristics and longevity of concrete structures, with a specific focus on the performance and design of beams composed of light gauge steel hollow sections (LGSHS) filled with steel fiber-reinforced concrete (SFRC) under flexural conditions. SFRC, known for its exceptional fire resistance, emerges as a promising alternative to Ordinary Portland Cement (OPC) in elevating concrete properties. The experimental and numerical findings consistently demonstrated a noteworthy 12% increase in maximum loading capacity, exhibiting a consistent curved trend at the moment against mid-span displacement when employing the composite material. Finite Element Analysis (FEA) modeling was used to scrutinize core concrete failure patterns, residual displacements of external metal during the load-carrying process, and load distribution patterns throughout the structural element. The infusion of SFRC into light gauge steel sections was found to enhance load-carrying capacity, ductility, and toughness. This paper scrutinizes the mechanical properties and structural behavior of LGSHS filled with SFRC, encompassing steel and concrete properties, member geometry, and response to fire exposure. The primary objective is to assess the load-deformation characteristics of rectangular hollow beams formed by concrete-filled steel tubes (CFST) filled with SFRC. The investigation aims to determine load-carrying capacity, strain, deformation capacity, ductility, and failure characteristics under ambient and elevated temperatures. structures (LGSHS fiberreinforced fiber reinforced (SFRC conditions resistance OPC (OPC 12 capacity midspan mid span material FEA (FEA loadcarrying carrying process element ductility toughness geometry exposure loaddeformation concretefilled CFST (CFST strain temperatures 1

This study investigates the mechanical properties of thermoplastic polyurethane (TPU) composites reinforced with multi-walled carbon nanotubes (MWCNTs) for application in athletic protective gear. The objectives were to (1) systematically evaluate the effects of MWCNT loading level and alignment on the tensile, compressive, hardness, and impact properties; (2) identify an optimal MWCNT content range for balanced enhancements; and (3) explore scalable fabrication methods. MWCNT/TPU composites with 0.5–4 wt% loading were prepared by solution mixing and compression molding. Mechanical testing revealed significant improvements, with 62 MPa tensile strength (+19%), 507 MPa modulus (+23%), and 10% higher impact energy absorption achieved at 1–4 wt% MWCNT. MWCNT alignment further enhanced the properties, while loadings above 2 wt% showed some embrittlement. Microstructural characterization evidenced good MWCNT dispersion and interfacial bonding. The results demonstrate that low MWCNT additions can substantially enhance the strength, stiffness, and impact resistance of TPU. This indicates great potential for developing advanced, lightweight athletic protective equipment like helmets and pads with improved energy absorption and durability. Future work will focus on optimizing composite processing and design for specific gear applications. TPU (TPU multiwalled multi walled MWCNTs (MWCNTs 1 (1 compressive hardness (2 enhancements 3 (3 methods MWCNTTPU 054 0 5 4 0.5– wt molding improvements 6 +19%, 19 +19% , (+19%) 50 +23%, 23 +23% (+23%) 10 14 1– embrittlement bonding stiffness advanced durability applications ( 05 0.5 +19 (+19% +23 (+23% 0. +1 (+19 +2 (+23 + (+1 (+2 (+

Abstract Due to collapse of buildings, the earthquakes in India and other countries have resulted in the death of people and damage to property. While it is impossible to prevent earthquakes, it is possible to lessen the damage they cause to existing structures by taking the necessary measures. It becomes crucial to perform an assessment first, then identify the weak members, and finally, carry out the necessary strengthening. Using pushover analysis, this study aims to evaluate the existing R.C. building in Zone-III. The analysis research shows the building’s performance levels, component behaviour, failure mechanism, and hinge formation. Externally wrapped GFRP sheets were used to strengthen the existing member’s deficiency. buildings property measures first members finally strengthening RC R C R.C ZoneIII. ZoneIII Zone III. III Zone-III s levels behaviour mechanism formation member deficiency

ABSTRACT This study examines the effects of using crushed Printed Circuit Board (PCB) (also known as E-waste aggregate) in concrete as a partial substitute for regular coarse aggregate (NCA). M25 grade concrete was utilized. After substituting 0%, 10%, and 15% of the natural coarse aggregates with E-waste aggregate, three combinations were still complete. Verified examples continue to focus on strength attributes, after which long-lasting characteristics such as aquatic concentration, thermal expansion, and abrasion encounter tests were carried out. Test results proved that when the replacement percentage of Electronic waste aggregate was higher significant reduction in strength properties was noticed. It is container remains credited to the reality that incorporation of E-waste aggregate slows down the hydration process that would lead to a significant loss in strength. However, it was observed that mix made with 10% and 15% E-waste aggregate shows better resistance against durability properties than control mix concrete. It was also observed that utmost care should be taken for maintaining proper workability and removal of toxic substances in E-waste aggregate for better forte and toughness properties. PCB (PCB Ewaste E NCA. NCA . (NCA) M M2 utilized 0 0% 10 15 complete attributes longlasting long lasting concentration expansion out noticed However (NCA 1

ABSTRACT This work aims to analyze the morphological evolution of the commercial A332 aluminum alloy produced via direct casting during the thixoforming process. The characterization of the solid-liquid transition, that is, the working temperatures corresponding to the solid fractions of 77%, 67% and 52% were determined via differential scanning calorimetry (DSC) tests, then the alloy was reheated until the temperature of and maintained for 0 s, 30 s and 90 s treatment times. Through conventional metallography, an increase in the size was observed during the maintenance of the alloy to the semi-solid band for the time of 90 s of treatment being the main mechanism for this change is the phenomenon of ostwald ripening followed by coalescence. It is known that the smallest solid fraction provided higher values of size of primary globules and grains, however, it presented low values of apparent viscosity around 105 Pa.s due to the lower presence of solid phase in the alloy structure and consequently less resistance to flow. This value low apparent viscosity makes the alloy suitable for used as a raw material in thixoforming processes. A A33 process solidliquid liquid transition 77 77% 67 52 DSC (DSC tests 3 9 times metallography semisolid semi coalescence grains however 10 Pas Pa flow processes A3 7 6 5 1

RESUMO Este trabalho visa analisar a evolução morfológica de uma liga comercial de alumínio A332 produzida via lingotamento contínuo convencional durante o processo de tixoconformação. A caracterização da transição sólido-líquido, ou seja, as temperaturas de trabalho correspondentes as frações sólidas de 77%, 67% e 52% foram determinadas via ensaios de análise térmica de calorimetria diferencial de varredura (DSC), na sequência a liga foi reaquecida até as temperaturas de trabalho e mantidas pelos tempos de tratamento de 0 s, 30 s e 90 s. Por meio da metalografia convencional observou-se o aumento no seu tamanho durante a manutenção da liga à faixa semissólida para o tempo de 90 s de tratamento sendo o principal mecanismo para essa alteração o fenômeno de ostwald ripening seguido por coalescência. Tem-se que a menor fração sólida proporcionou maiores valores de tamanho de glóbulos primários e de grãos, porém apresentou baixos valores de viscosidade aparente em torno de 105 Pa.s devido a menor presença de fase sólida na estrutura da liga e consequentemente menor resistência ao escoamento. Este baixo valor de viscosidade aparente torna a liga propícia a ser utilizada como matéria-prima nos processos de tixoconformação. A33 tixoconformação sólidolíquido, sólidolíquido sólido líquido, líquido sólido-líquido seja 77 77% 67 52 DSC, DSC , (DSC) 3 9 observouse observou se coalescência Temse Tem grãos 10 Pas Pa escoamento matériaprima matéria prima A3 7 6 5 (DSC 1

The microstructure, mechanical properties, and heat treatment process relationships of 45MnVS non-tempered steel were investigated. Different grain sizes and tissue ratios were obtained after heating and holding at 950, 1050, and 1150 °C for 30 min, respectively, and cooling at different cooling conditions and cooling rates. As the austenitizing temperature increased, the grain size and the elongation and section shrinkage of the experimental steels decreased. At the same time, the content of ferrite and pearlite in the tissue gradually decreases, the content of sorbite and troostite rises, and the strength and hardness of the experimental steel increase. With the increase of cold speed, ferrite’s content decreases, sorbite and troostite’s content increases, and strength and hardness increase. The original austenite grain size also influences the tissue ratio. As the austenite grain refines, the ferrite transformation temperature increases during cooling and the ferrite content in the tissue rises after cooling. microstructure properties MnVS nontempered non tempered investigated 950 1050 115 C 3 min respectively rates increased decreased time decreases speed ferrites s troostites ratio refines 95 105 11 9 10 1

ABSTRACT This study assessed the properties of particleboard produced from the replacement of urea formaldehyde with cassava starch. Cassava starch (CS) and urea-formaldehyde (UF) were mixed at percentages of 100/0, 90/10, 70/30, 50/50, and 0/100, respectively. The mixture was added to the wood particles at 15% adhesive content based on the weight of oven-dried particles. Particleboards of sizes 20 mm × 300 mm × 300 mm and a targeted density of 600 kg m–3 were manufactured by hot-pressing at 170 °C, compacting pressure 3.5 MPa for 8 min. Physical and mechanical properties (density, thickness swelling, water absorption, static bending, and hardness) were tested. The physical and mechanical properties also increased in the highest proportions of UF. Comparatively, manufactured with 50% CS + 50% UF, it performed better in all the evaluated properties. Thus, it could adopt the latter mixed ratio in the industry to reduce the quantity and cost of UF and its environmental emissions. The results obtained were adequate and in conformity with international standards. Hence, it could mix cassava starch and urea formaldehyde adhesives in different ratios to get desirable properties. It is possible to conclude that cassava starch could be considered a sustainable alternative adhesive. (CS ureaformaldehyde (UF 1000 100 0 100/0 9010 90 10 90/10 7030 70 30 70/30 5050 50 50/50 0100 0/100 respectively 15 ovendried oven dried 2 60 m3 m 3 m– hotpressing hot pressing 17 C °C 35 5 3. min density, (density swelling absorption bending hardness tested Comparatively Thus emissions standards Hence 100/ 901 9 1 90/1 703 7 70/3 505 50/5 010 0/10 6 90/ 70/ 50/ 01 0/1 0/

ABSTRACT Structural materials play an essential role in equipment and constructions, with properties such as strength and stability. Granite and marble are widely used for structural building materials such as cladding, sinks and countertops. It is possible to recycle waste from these rocks in the production of new parts, reducing the environmental impact. In Brazil, there is a high amount of construction and demolition waste, with most of the raw material becoming waste before the product is finished. Studies indicate that the incorporation of ornamental stone waste into cementitious products can significantly reduce environmental impact and improve its sustainability. The present work presents an experimental study for the manufacture of resin granite test specimens with residues from different dosages and resin epoxy levels. Flexural strengths of up to 7, 11, 24 and 28 MPa are achieved for resin contents of 5%, 10%, 15% and 20% respectively. The material has anisotropic characteristics and makes good use of almost all of the size ranges of waste used. Future reverse engineering studies of the resin are also necessary to expand knowledge and further optimize its application. constructions stability cladding countertops parts Brazil finished sustainability levels 7 11 2 5 5% 10 10% 15 20 respectively application 1

ABSTRACT There is a growing need for intervention in existing structures to recover or increase strength capacity. The use of composite materials, such as carbon fiber, has been efficient, but cost is an obstacle. The application of steel bars as a strengthening element is an alternative and technically viable material, but there are few studies in the literature. This work carried out an experimental series with three reinforced concrete beams without transverse reinforcement, and strengthened in shear with steel bars using the near-surface mounted (NSM) technique. The load, displacement and cracking pattern were monitored in the experiment. The results demonstrated the efficiency of the strengthening with an increase of 69% in the ultimate load and 63% in the load for the appearance of the first cracks compared to the reference beam. The strengthening also increased the ductility of the beams before sudden shear failure. Numerical models via the finite element method (FEM) were carried out in the ABAQUS software using different elements and meshes. The numerical results were validated with the experimental results, and it was observed that the use of quadratic elements compared to linear elements can better represent the cracking pattern and the load capacity of the beams. The mean ratio of numerical/experimental results for maximum load of strengthening beams was 0.94. materials fiber efficient obstacle material literature reinforcement nearsurface near surface NSM (NSM technique experiment 69 63 beam failure FEM (FEM meshes numericalexperimental 094 0 94 0.94 6 09 9 0.9 0.

RESUMO Há uma necessidade crescente de intervenção nas estruturas de concreto armado existentes para recuperar ou aumentar a sua capacidade resistente. O uso de materiais compósitos, como a fibra de carbono, tem sido eficiente, mas o custo ainda é um entrave. A aplicação de barras de aço como elemento de reforço apresenta-se como material alternativo e tecnicamente viável, porém existem poucos trabalhos na literatura. Desse modo, este trabalho realizou uma série experimental com três vigas de concreto armado sem armadura transversal, e reforçadas ao cisalhamento com barras de aço utilizando a técnica near-surface mounted (NSM). Foram monitorados no experimento a carga, o deslocamento e o padrão de fissuração. Os resultados demonstraram a eficiência do reforço com aumento de 69% da carga última e 63% da carga para surgimento das primeiras fissuras comparados a viga de referência. O reforço também aumentou a ductibilidade das vigas antes da ruptura brusca por cisalhamento. Modelos numéricos via método dos elementos finitos (MEF) foram realizados no software ABAQUS utilizando diferentes tipos de elementos e malhas. Os resultados numéricos foram validados com os resultados experimentais e foi observado que o uso de elementos quadráticos comparados a elementos lineares consegue representar melhor o padrão de fissuração e a capacidade de carga das vigas. A relação média dos resultados numérico/experimental para carga máxima das vigas reforçadas foi de 0,94. resistente compósitos carbono eficiente entrave apresentase apresenta se viável literatura modo transversal nearsurface near surface NSM. NSM . (NSM) 69 63 referência MEF (MEF malhas numéricoexperimental numérico 094 0 94 0,94 (NSM 6 09 9 0,9 0,

ABSTRACT Developing high-performing bio adhesives for enhancing the bonding strength of cement-based materials is highly desirable as they improve workability, corrosion resistance and durability of the concrete. The present effort aims at stemming a novel bio admixture comprising agricultural products Cassava starch and Xanthan gum as well examines the effect of incorporation of it into the cement. The composition of xanthan gum is varied in the starch mixture systematically in the ratios namely 1:0.25, 1:0.5 and 1:0.75. As-prepared bio admixtures are characterized through Fourier Transform Infra-Red spectroscopy, X-Ray Diffraction, Thermo Gravimetric Analysis, contact angle and Scanning Electron Microscopy-Energy Dispersive X-ray studies. These results demonstrated that presence of optimal amount of xanthan gum facilitates the binding nature of starch and promotes better bond strength as it significantly improved the bonding capacity as well as hydrophilic nature of starch thereby augmenting the bonding strength when used in cement mortar. The bio admixture filler material occupied the voids between the mortar matrix, thus reducing the porosity. The beneficial effect of as-prepared bio admixture has been reflected in the compressive strength that has been enhanced by 16.6% when optimized quantity (1.5 wt.%) of the bio admixture is added to the mortar. highperforming high performing cementbased based workability concrete 10.25, 1025 1 0.25, 0 25 1:0.25 10.5 105 0.5 5 1:0. 10.75. 1075 0.75. 75 1:0.75 Asprepared As prepared InfraRed Infra Red spectroscopy XRay X Ray Diffraction Analysis MicroscopyEnergy Microscopy Energy Xray ray studies matrix porosity asprepared 166 16 6 16.6 1.5 15 (1. wt.% wt 10 10.25 102 025 0.25 2 1:0.2 10. 05 0. 1:0 10.75 107 075 0.75 7 1:0.7 16. 1. (1 wt. 10.2 02 0.2 1: 10.7 07 0.7 (

The objective of this work was to study the reversion of the strain-induced α-martensite to γ-austenite in three sets of AISI 304, 316-L and 347 stainless steels specimens. To obtaining a high amount of αʹ-martensite (γ → αʹ ), the samples were submitted to 63% reduction in thickness by cold rolling at a temperature of –70 ºC. The reversion of martensite to austenite was made by means of 1-hour isothermal heat treatments between 200 and 1000 ºC (αʹ → γ). Martensite amounts were determined by measurements made with a commercial feritscope. The main analysis of reversion was performed by differential scanning calorimetry (DSC) studies with heating rates of 10, 20 and 40 °C/min. It was determined that under continuous heating the deformation-induced reversion is carried out by a superposition of the diffusional and shear mechanisms, for the heating rates tested. The reversion begins via diffusion-controlled mechanism at temperatures between 414 and 453 °C and ends via non-diffusional mechanism between 557 and 633 °C. On the other hand, the energy per unit mass of the transformation turned out to be between 37 and 63 J/g; and it was found that this depends on the heating rate. straininduced strain induced αmartensite α γaustenite γ 304 316L L 316 34 specimens αʹmartensite , ) 70 –7 1hour hour 1 100 γ. . γ) feritscope DSC (DSC 10 2 4 Cmin C min °C/min deformationinduced deformation mechanisms tested diffusioncontrolled diffusion controlled 41 45 nondiffusional non 55 hand 3 6 J/g Jg J g rate 30 31 7 – 5