Effect of cream formulation of fenugreek seed extract on some mechanical parameters of human skin

Purpose: To determine the effect of an emulsion formulation of fenugreek (Trigonella Foneum-Graecum L) seed extract on some mechanical parameters of the skin of healthy human volunteersMethods: A water-in-oil emulsion cream base without fenugreek seed extract which served as control, and a similar formulation containing 4 %w/v of the extract in the internal (aqueous) phase were prepared. Each of the formulations was applied to the cheeks of 10 human volunteers for a period of 4 weeks and some mechanical parameters (R0, R1, R2, R3, R4, R5, R6, R7, R8 and R9) of the skin were measured weekly using Cutometer MPA 580. Results: The results indicate that the effects of the creams on skin mechanical properties were significant (p < 0.05) with respect to time, except for R4 and R9. The extract-containing cream substantially increased skin elasticity, hydration and the ability of skin to resist photo-aging when compared to the base. Conclusion: Both the cream base and the cream containing fenugreek extract demonstrated significant (p < 0.05) improvement in all mechanical parameters related to skin elasticity, ageing, hydration and fatigue but the effect of the extract cream was more pronounced in some cases

Catalytic removal of Alizarin Red using chromium manganese oxide nanorods: degradation and kinetic studies

Dye removal through photocatalytic degradation employing nanomaterials as catalysts is a growing research area. In current studies, photocatalytic alizarin red (AR) dye degradation has been investigated by designing a series of Cr based manganese oxide nanomaterials (MH1–MH5). Synthesized nanomaterials were characterized by powder X-ray diffraction, scanning electron microscopy/energy dispersive x-ray, Brunauer–Emmett–Teller, and photoluminescence techniques and were utilized for photocatalytic AR dye degradation under UV light. AR dye degradation was monitored by UV–visible spectroscopy and percent degradation was studied for the effect of time, catalyst dose, different dye concentrations, and different pH values of dye solution. All the catalysts have shown more than 80% dye degradation exhibiting good catalytic efficiencies for dye removal. The catalytic pathway was analyzed by applying the kinetic model. A pseudo second-order model was found the best fitted kinetic model indicating a chemically-rate controlled mechanism. Values of constant R2 for all the factors studied were close to unity depicting a good correlation between experimental data

Effect of water infiltration on the mechanical behaviour of unsaturated soil

Natural slopes and embankments are generally unsaturated in nature with negative pore water pressure adding to the shear strength and hence the stability of the slopes. During the event of rainfall, pore water pressure becomes less negative or even positive as a result the shear strength of soil decreases and failure occur. Therefore, the strength and deformation characteristics for unsaturated soil become important when analysing the stability of these types of slopes. In this study, a triaxial test apparatus was used to study the effect of water infiltration on the mechanical behaviour of unsaturated soil. The test results show that water infiltration decreased with increase in net confining stress and the stress paths were independent of the matric suction, the net confining stress and the shearing conditions for the present experimental study

Optimization of constituent proportions for compressive strength of sustainable geopolymer concrete: A statistical approach

Geopolymer concrete (GPC) is an environmentally friendly and sustainable concrete produced through the geopolymerization process, involving the combination of alumino silicate materials with alkaline solutions. It has unique advantage of being carbon-negative which helps reduce carbon dioxide levels in the atmosphere. One challenge with making GPC is the significant variation in compressive strength that arises from differences in constituent proportions, specimen ages, andcuring conditions. There is a need to optimize the GPC constituents to achieve the desired compressive strength. To address this issue, a comprehensive dataset comprising 1242 data points from existing literature on fly ash-based GPC (FA-based GPC) was compiled for the purpose of optimizing the constituent proportions of GPC using statistical analysis. Nine independent variables were selected to develop the predictive models for compressive strength using linear (LRA), multilinear (MRA), and non-linear (NRA) regression analyses. The models were assessed using scatter plots between experimental and predicted responses and adopting the performance criteria such as the statistical significance of the model unknowns, R2 values, root mean square error (RMSE), mean absolute error (MAE), and scatter index (SI). LRA revealed that the compressive strength of GPC is not dependent on any single independent variable. Therefore regression analysis with multiple independent variables was conducted. From MRA, ±15 % error for training dataset and (15–20) % error for validating dataset was estimated. The R2, RMSE, MAE, and SI values were found to be 0.8086, 6.11, 5.35, and 0.21. NRA predicted the compressive strength more efficiently because it provides the error ±10 % for both training and validating datasets with R2, RMSE, MAE, SI values of 0.8321, 5.46, 4.77, and 0.19. Further, curing temperature, specimen age, Na2SiO3/NaOH ratio, I/b ratio, and aggregate content were found as the most significant independent variables. The time and cost-effective design mix for FA based GPC can be prepared using the regression models presented in the current work

Analysis of communication tower with different heights subjected to wind loads using TIA-222-G and TIA-222-H standards

Due to advancements in telecommunications, towers need special attention in terms of the analysis and design under wind loads. The Telecommunications Industry Association (TIA) in 2005 released a standard “TIA-222-G” which has gained a widespread reference for the analysis and design of communication towers. In 2018, TIA released the latest standard TIA-222-H. The latest TIA-222-H standard has some additional features, e.g. limit states for analysis of mounting systems, enhanced climber safety requirements, construction-related loading, etc. To date, not many studies are available describing how much change in member axial forces occurs with the tower height while using the latest standard for analysis. This study’s main objective is to provide guidelines for wind load calculation on tower body, appurtenances, and other structures and compare the member axial forces induced by the wind loads on different tower heights (40, 60, and 80 m) as per TIA-222-G and TIA-222-H standards. The procedure presented in the paper about the design calculations of wind load is a useful guide for structural engineers involved in the analysis and design of communication towers. The analysis results showed that the member axial forces increased by 22% to 37%, which can assist the practitioner in more optimized design

Behavior of Scaled Infilled Masonry, Confined Masonry & Reinforced Concrete Structures under Dynamic Excitations

This research investigates the nonlinear behavior of scaled infilled masonry (IFM), confined masonry (CM), and reinforced concrete (RC) structures by utilizing and validating two tests from the literature as benchmarks. The validation was based on a comparison with the pushover results of small-scaled physical tests and their numerical modeling. Numerical modeling of small-scale (1:4 and 1:3) IFM, CM, and RC models has been carried out with Finite Element Modelling (FEM) and Applied Element Modelling (AEM) techniques using SAP2000 and the Extreme Loading for Structures (ELS) software, respectively. The behavior of the structure under lateral loads and excitations was investigated using nonlinear static (pushover) and nonlinear time history (dynamic) analysis. The evaluation of the pushover analysis results revealed that for IFM, the %age difference of tangent stiffness was 4.2% and 13.5% for FEMA Strut and AEM, respectively, and the %age difference for strength was 31.2% and 2.8% for FEMA Strut and AEM, respectively. Similarly, it was also calculated for other wall types. Dynamic analysis results from FEM and AEM techniques were found in the fairly acceptable range before yield; however, beyond yield, AEM proved more stable. Finally, the results also showed that the numerical study can be utilized for the evaluation of small-scale models before performing the physical test

Experimental study on strength and endurance performance of burnt clay bricks incorporating marble waste

Burnt clay brick is one of the oldest and most widely used construction materials. The production of burnt clay bricks with various waste materials can help reduce the environmental hazards and improve brick performance at low manufacturing costs, thereby leading towards more sustainable construction. This research aimed to evaluate the effect of using waste marble powder (WMP) in varying percentages, i.e., 0, 3, 6, 9, 12, and 15%, by weight of clay in an industrial brick kiln plant. A range of mechanical and durability tests was performed on the raw material, i.e., clay, WMP, and bricks, to quantify their performance. It was observed that incorporation of WMP resulted in a reduced unit weight of the bricks, making the structure lighter in weight. Moreover, compressive strength and freeze thaw test results for all the brick specimens and sulfate tests for the brick specimens with 12% WMP addition were within the Building Code of Pakistan, and ASTM C67 prescribed limits. Finally, it can be concluded that WMP up to 12% by weight of clay can be incorporated to prepare burnt clay bricks, which can reduce the environmental waste to achieve sustainability and economy for the brick industry

Use of Reservoir Sediments to Improve Engineering Properties of Dune Sand in Oman

Managing sediments dredged from reservoirs of recharge dams is an environmental issue, however, these sediments can be an abundant and economical source of fine-grained fill soil. This experimental investigation quantifies the geotechnical properties of a reservoir sediment used to improve engineering properties of a poorly graded dune sand in Oman. The binary mixes were prepared with different percentages (5, 10, 20, 50, 75, 90, 95%) of sediment with sand. Laboratory tests such as gradation, consistency limits, compaction, and unconfined compression tests were performed to measure the engineering characteristics of the binary mixtures. The results showed that the maximum dry density increases up to a sediment content of 50% and then decreases with further increase in the sediment content. The optimum water content increases with the increase in sediment content from 17% for pure sand to 22.5% for pure sediment. The optimum moisture content shows a good correlation with the plastic limit of the binary mixture of sand and sediment. The unconfined compressive strength substantially increases with sediment content up to 75% and then decreases with further increase in the sediment content. The binary mixture of sand sediment is sensitive to moisture, however, the order of strength stability against moisture is dune sand mixed with 75, 50, and 20% sediments. The addition of sediment to dune sand improved the uniformity coefficient to some extent with an increase in the maximum and minimum void ratios as well. The elemental analysis of the sediment confirms that the material is non-contaminated and can be employed in geotechnical engineering applications as a sustainable and environmentally friendly solution

Damage Characteristics of Thermally Deteriorated Carbonate Rocks: A Review

This review paper summarizes the recent and past experimental findings to evaluate the damage characteristics of carbonate rocks subjected to thermal treatment (20–1500 °C). The outcomes of published studies show that the degree of thermal damage in the post-heated carbonate rocks is attributed to their rock fabric, microstructural patterns, mineral composition, texture, grain cementations, particle orientations, and grain contact surface area. The expressive variations in the engineering properties of these rocks subjected to the temperature (>500 °C) are the results of chemical processes (hydration, dehydration, deionization, melting, mineral phase transformation, etc.), intercrystalline and intergranular thermal cracking, the separation between cemented particles, removal of bonding agents, and internal defects. Thermally deteriorated carbonate rocks experience a significant reduction in their fracture toughness, static–dynamic strength, static–dynamic elastic moduli, wave velocities, and thermal transport properties, whereas their porous network properties appreciate with the temperature. The stress–strain curves illustrate that post-heated carbonate rocks show brittleness below a temperature of 400 °C, brittle–ductile transformation at a temperature range of 400 to 500 °C, and ductile behavior beyond this critical temperature. The aspects discussed in this review comprehensively describe the damage mechanism of thermally exploited carbonate rocks that can be used as a reference in rock mass classification, sub-surface investigation, and geotechnical site characterization

Utilization of Fly Ash as a Viscosity-Modifying Agent to Produce Cost-Effective, Self-Compacting Concrete: A Sustainable Solution

Sufficient deformability can be achieved in concrete while maintaining segregation resistance either by using a chemical viscosity-modifying admixture (VMA) or increasing the fine content in the concrete. Using VMA, the initial cost of self-compacting concrete (SCC) increases, making it unsuitable for general construction. As a result, alternative methods for lowering the cost of SCC must be investigated. In this study, we assess the effectiveness of fly ash (FA) as a viscosity-modifying agent in the production of cost-effective and durable SCC. We also forge new pathways for sustainable development. The percentage of FA, superplasticizer dose, and water/binder ratio were varied, whereas the amounts of cement and water, as well as fine/coarse aggregate content were kept constant. Fresh properties, such as flow, filling and passing abilities, viscosity, and segregation resistance, were measured. Compressive/flexural strength, density, water absorption, and rate of water absorption of hardened SCC were also determined. The test results showed that fly ash can be used as an alternative to a VMA to produce cost-effective, self-compacting concrete. The slump flow of the various fresh-state concrete mixes ranged from 200 to 770 mm, with an L-box ratio of 0 to 1 and a flow time of 2.18 to 88 s. At 28 and 56 days, the compressive strengths of the concrete mixes with fly ash were found to be comparable to those of the control concrete mixes with VMA. The cost of ingredients for a specific SCC mix is 26.8% lower than the price of control concrete, according to a cost comparison assessment