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Impact of process parameters on noise emission and microhardness during dry turning of squeeze cast Al 7075 alloy: A case study
No full textThe objective of the research is to investigate the machinability characteristics of squeeze cast Al 7085 through carbide insert using Taguchi design of experiment and obtain the parametric optimization of responses such as noise emission and vickers micro-hardness. Squeeze cast sample surface generates micro-hardness of 139.3-149.6 HV whereas emissions of noise during dry turning are in the range of 68.1dB-77.1dB respectively. Impact of process parameters on noise emission are increasing in trend with 52.94%, 32.33% and 14.69% contribution at 95% confidence level. The contribution of cutting speed and depth of cut on micro-hardness of specimen are significant with 69.39% and 29.39% respectively. Prediction models through multiple linear regressions are found to be fitted well as coefficient of regression approaches one. During desirability multi-response optimization approach, the optimal parameters are found to be vc: 127.255 m/min, f: 0.05 mm/rev and ap: 0.1 mm with minimum values of micro- hardness and noise emission are 141.752 HV and 71.5405dB respectively. The outcome of the research has shown improvements in terms of good machinability and may be adopted in industries for green and sustainable manufacturing process
Static instability of an asymmetrical two-layered beam supported by a Pasternak base under thermal gradient and an axial pulsating load
No full textThis study focuses on lightweight structural components that are commonly used in mechanical, marine, and aerospace systems where achieving high strength at low weight is a key design objective. The suggested beam in this analysis eliminates the need for a viscoelastic core and achieves reduced mass without sacrificing stiffness by bonding two dissimilar elastic materials together. To simulate actual operating conditions, the model is exposed to a thermal gradient and an axial pulsating load. The governing non-dimensional Hamilton’s concept is used to generate equations and the related boundary conditions, and Galerkin’s approach further streamlines them for computational use. For both pinned & pinned and clamped & pinned edge conditions, the impact of geometric ratios, elastic modulus variation, taper characteristics, foundation rigidity, and thermal effects is examined. The effect of these parameters on the beam’s static stability is evident from numerical results derived from MATLAB simulations
Production and characterization of sustainable aluminium matrix composites reinforced with industrial waste materials via stir casting for lightweight and high-strength applications
No full textThe present research work deals with the fabrication and characterization of AMC-based composites through the addition of industrial wastes in the form of iron (Fe) and copper (Cu) particles by stir casting. The investigation covers their microstructure evolution, mechanical properties, and porosity. With the optimized stirring parameters adopted in the study, three composites were fabricated: as-cast scrap industrial aluminum alloy (SIAA), Al-Fe, and Al-Cu. Accordingly, the Al-Fe composite exhibited a higher tensile strength of 117.6%, which rose to 148 MPa from that of the as-cast SIAA with a value of 68 MPa. This is attributed to the presence of a refined microstructure, homogeneous dispersion of Fe particles, and subsequent intermetallic formation. Its ductility was compromised in the range of 0.5–1% elongation. The Al-Cu composite exhibited an intermediate strength of 95.36 MPa and demonstrated better ductility in the range of 3–3.5% elongation. However, it exhibited higher submicron porosity of 13.7% along with interfacial oxides, as revealed from SEM and elemental mapping. Microstructural studies further established that the superior performance of Al-Fe is attributed to the pore-free interfaces and the segregation of Fe-Si at the grain boundaries, whereas the limitations in case of Al-Cu arise due to the presence of nano-porosity and Cu-Mg-O clustering. These results demonstrate the feasibility and acceptability of waste-based reinforcement in AMC fabrication. Specifically, the Al-Fe composite emerges as a high-strength and sustainable class. This work contributes toward the development of eco-friendly composites by establishing a relation between processing parameters, interfacial chemistry, and associated mechanical properties. It also demonstrates promising information for industrial applications pertaining to lightweight engineering
Retraction Notice: Object Detection with Audio Feedback
No full textWe take a zero tolerance to any situation where fraudulent research is published in our journals. As a result, this article has been retracted by the Publisher because it is suspected to be a nonsensical computer-generated publication with a number of tortured phrases and irrelevant references.
Additional measures have been implemented to prevent these issues from reoccurring.
EDP Sciences is extremely grateful to anonymous whistleblowers and the Problematic Paper Screene
Optimization of Concentration and Frequency of Nutrient Application Based on Goat Manure Concentrate in Orchid Nurseries
No full textAchieving optimal flower quality depends on precise cultivation practices, particularly in managing environmental and nutritional factors. Inadequate nutrient management can reduce vegetative growth, photosynthetic pigment levels, and flower quality, while suboptimal water and nutrient regulation often hamper seedling productivity. Because moon orchids require specific humidity, watering frequency, and nutrient concentrations, smart farming technology is needed to control these conditions accurately. This study investigated the interaction between nutrient concentration and application frequency on the growth of Phalaenopsis orchids in a smart farming system, employing a factorial randomised block design. Treatments included nutrient concentrations of 30%, 3%, and 0.3% (v/v) and application frequencies of once, twice, and three times daily at two-day intervals. Observed variables included leaf number, leaf area, chlorophyll content, and plant weight gain. Results showed no significant interaction between the two factors across all parameters. However, the 0.3% concentration produced the best growth response, comparable to 3%, while 30% inhibited growth. Application frequency significantly affected leaf area and weight gain, with once- and twice-daily treatments yielding similar results. Overall, low nutrient concentrations (0.3-3%) applied once or twice daily were identified as the most efficient and sustainable strategy for cultivating Phalaenopsis orchids in smart farming systems
Renoprotective Effects of
No full textDiabetes mellitus is a major global health challenge, often leading to severe metabolic and systemic complications such as diabetic nephropathy. Hyperglycemia and oxidative stress contribute significantly to renal impairment, characterized by glomerular hypertrophy, basement membrane thickening, and elevated plasma creatinine. This study investigated the renoprotective potential of aqueous Moringa oleifera leaf extract in streptozotocin (STZ)-induced diabetic male Sprague Dawley rats. A total of 40 rats were divided into four groups: normal control, negative control (diabetic untreated), positive control (diabetic treated with 500 mg/kg metformin), and treatment group (diabetic treated with 400 mg/kg Moringa oleifera leaf extract). Treatments were administered orally for 14 and 21 days, respectively. Renal parameters assessed included kidney weight, glomerular diameter, plasma creatinine levels, and histological alterations. Diabetic control rats exhibited marked renal abnormalities with glomerular disruption, tubular inflammation, and significantly elevated plasma creatinine. Administration of Moringa oleifera leaf extract, however, reduced plasma creatinine levels significantly compared to diabetic controls, restored glomerular architecture, and attenuated kidney hypertrophy and glomerular enlargement after 21 days. Moringa oleifera leaf extract demonstrated renoprotective effects likely mediated by its antioxidant bioactive compounds. These findings support its potential role as a complementary therapeutic agent for managing diabetic nephropathy
Comparative Analysis of Antioxidant Activities of Matoa
No full textThe fruit peel of matoa (Pometiapinnata), commonly discarded as waste, is known to contain bioactive compounds with high antioxidant potential. This study aims to compare the antioxidant activity of P. pinnata fruit peel extracts using solvents of varying polarity (ethanol, n-butanol, and ethyl acetate) and assays (DPPH, ABTS, and FRAP). IC50 values were calculated using a four-parameter logistic model, and FRAP values were reported as mg GAE/g of extract. Phytochemical screening revealed that the ethanolic extract (ETM) contained the most diverse secondary metabolites, including phenolics, flavonoids, tannins, terpenoids, and triterpenoids. The DPPH assay showed the highest antioxidant capacity in ETM (IC50 = 44.90 ppm), followed by ethyl acetate (EAM, 95.66 ppm) and n-butanol (NBM, 397.80 ppm). In the ABTS assay, ETM and EAM demonstrated weaker activities (IC50 = 3424 ppm and 13,485 ppm, respectively), while NBM showed no significant activity. The FRAP results indicated that ETM exhibited the strongest reducing power (6.26 ± 0.08 mg GAE/g), followed by EAM (5.44 ± 0.07 mg GAE/g) and NBM (0.77 ± 0.03 mg GAE/g). Solvent polarity influences antioxidant activity and bioactive composition, and ethanol is the most effective solvent for extracting antioxidant compounds from matoa peel
Regional Sensitivity Analysis for Multi-Performance Optimization of Rural Dwellings: A Case Study in Tianjin
No full textWith the advancement of building energy efficiency simulation technology, sensitivity analysis has become increasingly important in optimizing architectural design. This study examines typical rural dwellings in the Beijing–Tianjin–Hebei region, using Regional Sensitivity Analysis (RSA) to assess how design parameters affect energy consumption, carbon emissions, costs, and thermal comfort. Eleven parameters were analyzed through 1,000 simulations, including insulation type, envelope geometry, and photovoltaic configuration. Eave depth showed the highest sensitivity for all metrics, while roof insulation thickness and PV panel angle strongly influenced thermal performance and cost. The study also applies an RSA workflow to mixed continuous and categorical variables, with binning adjustment improving sensitivity results for discrete parameters. Based on sensitivity findings, differentiated optimization strategies were proposed: prioritizing passive shading and roof insulation for comfort optimization, while focusing on PV system scale for carbon emission and cost control. This study provides quantifiable evidence for low-carbon, efficient, and comfortable design in rural buildings
Research on Construction Technology of Conversion Floor of Super High-rise Building Main Structure Based on Composite Beam Method
No full textThe construction of the transfer floor of the main structure has an important impact on the quality and safety of high-rise and super high-rise buildings, and the composite beam method plays an important role in this link of construction. Based on this, this paper combined with the construction case of 3500mm thick structural transfer floor of a super high-rise building in Puyang, studied the application points and performance improvement effect of composite beam method. Compared with the conventional method, the peak temperature in the core area of the structure is controlled at 60.7~63.5 ℃, which is lower than the early warning threshold of 75 ℃, and the safety margin is 11.5~14.3 ℃; The maximum temperature rise is 36~40 ℃, which is lower than the critical standard of 45 ℃, and 5~9 ℃ lower than the conventional method; The extreme temperature difference between the inside and the surface, the surface and the environment is ≤ 24.6 ℃, which is lower than the control standard of 30 ℃, which is 5.4~6.2 ℃ lower than the conventional method, and the hydration heat effect is effectively suppressed. The 28d concrete strength is 1.2~1.4 times of the design grade, 26% higher on average, and the structural bearing capacity is significantly improved. After 60 days of pouring, there was no obvious crack in the transfer floor and floors 1-7, and the temperature crack prone to occur in the conventional thick plate transfer floor did not occur, and the crack resistance was significantly improved. The practice shows that the composite beam method can effectively solve the key problems such as load transfer, hydration heat control and cracks in the construction of thick plate transfer floor, and the construction safety and structural quality can be quantitatively improved compared with the conventional method
BIM-Based Carbon Emission Measurement for Building Whole Life Cycle: Model Construction, Stage Analysis and Case Verification
No full textAgainst the backdrop of global climate change, the construction industry accounts for ~40–50% of global greenhouse gas emissions, making low-carbon development an urgent priority. This study focuses on whole-life-cycle (WLC) carbon emission measurement of buildings and innovatively integrates BIM technology to address challenges such as inaccurate material quantification and fragmented data across stages. Taking a sports venue project in Xiqing District, Tianjin (total construction area 84,000 m², prefabrication rate 70.2%) as a case, a multi-disciplinary BIM model with LOD400 precision was constructed using Revit. For each WLC stage, targeted carbon emission measurement methods were developed:
Materialization stage: BIM visualization tools were used for prefabricated component design, BIM4D simulation optimized construction management, and a measurement model was built by linking BIM-derived material quantities to a carbon emission factor database (labor, materials, machinery).Operation and maintenance (O&M) stage: The BIM model (supplemented with component thermal/physical properties) was exported as a gbXML file to Green Building Studio, enabling quantitative calculation of annual energy consumption and carbon emissions.Demolition and renovation stage: “Waste” and “recyclable” attributes were assigned to BIM components to quantify waste/recyclables, and carbon emissions from demolition, transportation, and recycling were measured.
Case results show: (1) Total embodied carbon emissions of main building materials reached 25,470.5 tCO₂e, with steel structures (components + accessories) accounting for 62.6% (the largest share). (2) Among three O&M schemes, Scheme 3 (water chillers + geothermal energy + LED lighting) achieved the lowest carbon emission intensity (57.26 kgCO₂e/m²ꞏa), a 16.7 kgCO₂e/m²ꞏa reduction compared to Scheme 1 (water chillers + gas-fired boilers). (3) The O&M stage contributed over 80% of WLC carbon emissions, remaining the core for emission reduction.
This study’s innovation lies in integrating BIM with stage-specific carbon measurement methods: LOD400 models ensure accurate material quantification, gbXML-Green Building Studio realizes O&M data visualization, and component attribute assignment enables demolition-stage quantification. The findings provide a replicable technical framework for low-carbon building practices, empowering the construction industry’s green transformation