Mixing Percentage Research Articles

A chemical and isotopic approach to investigate groundwater dynamics in a coastal aquifer

The hydrogeological processes in two different zones of a sandy coastal aquifer of the province of Buenos Aires, Argentina, have been assessed on the basis of hydrochemical tools and environmental isotopes (2H and 18O). In general, groundwater in the sand dune barrier is either a Ca-HCO3 or a Na-HCO3 type, whereas in the coastal plain it is a NaCl type. In general terms, the isotopic composition of groundwater matches the average isotopic composition of the rainfall, which would indicate that there is no significant fractionation during the recharge process. However, the interpretation of data allowed the detection of different processes— rapid infiltration, selective infiltration, evaporation, mineral dissolution and mixing—in certain locations. The last process mentioned includes both natural lateral and vertical interface mixing, as well as the one generated by anthropogenic action (saline intrusion). There is a relationship between the variability of the isotopic contents and the thickness of the unsaturated zone. In the northern zone, its lesser thickness causes greater variability in isotopic contents, whereas in the southern zone a greater thickness is suggested by more homogeneous, clustered values. In both zones, selective infiltration was observed; they were represented by both highly depleted and highly enriched isotopic contents, as well as evaporation processes occurring prior to infiltration. Besides, in both zones it was possible to recognise the effects of the displacement of the freshwater–saltwater interface towards the continent as a consequence of intensive groundwater exploitation. The mixing percentage of salt water is about 51% for both conservative elements oxygen-18 and chloride. The importance of the association of hydrochemical and isotopic methodologies stands out as a tool in the sustainable management of groundwater resources in coastal sand-dune regions.

Characterization of groundwater recharge through tritium measurements

Abstract. After the nuclear weapons testing in the 1950s and 1960s, the atmospheric tritium levels have almost returned to natural levels (pre-1950 levels), which means that tritium is becoming more effective in determining transit times in hydrological systems. It has also been demonstrated that tritium is a non-reactive noble gas and in water is not subject to chemical reactions, absorption, or dissolution/precipitation processes, so it is conservative of the geochemical fingerprint of the source. In addition, it is used as an effective tracer of water contamination by landfill leachate, allowing to detect mixing percentages of the leachate up to levels not achievable with normal chemical analyses (less than 1 %). The purpose of the present work is to deepen the knowledge of the hydrogeochemical characteristics of the aquifers in the pedemontana area of the Venetian plain, and to formulate a conceptual framework of underground water circulation, aimed at understanding phenomena of contamination by toxic metals, harmful to human health. Tritium concentration analyses were performed on selected samples of groundwater collected in different wells in the south part of Treviso city to correlate the young age of the water recharge. The abundance of young waters, in fact, indicates a vulnerability of the aquifer to climate change with respect to possible contributions of surface waters, in particular to prolonged drought periods which could induce salinization dynamics.

Use of waste recycling coal bottom ash and sugarcane bagasse ash as cement and sand replacement material to produce sustainable concrete.

Concrete is widely used as a building material all over the world, and its use is increasing the demand of cement and sand in the construction industry. However, the limited resources and environmental degradation are driving scientists to develop alternative materials from vast volumes of agro-industrial wastes as a partial replacement for conventional cement. In the manufacture of concrete, cement is a major binding resource. This study looked into recycling agro-industrial wastes into cement, such as sugarcane bagasse ash (SCBA), coal bottom ash (CBA), and others, to create sustainable and environmentally friendly concrete. This study aims to see how the combined effects of agricultural by-product wastes affected the characteristics of concrete. SCBA is used to replace fine aggregate (FA) ranging from 0 to 40% by weight of FA, while CBA is used to replace cement content ranging from 0 to 20% by weight of the total binder. In this case, a total of 204 concrete samples (cubes and cylinders) are made using a mixed proportion of 1:1.5:3 and a water-cement ratio of 0.54. Workability, density, water absorption, and mechanical characteristics in terms of compressive and splitting tensile strengths were examined in this study. In addition, for each mix percentage, the total embodied carbon was determined. Workability, density, and water absorption were found to be considerably decreased when CBA and SCBA concentration increased. Due to the pozzolanic nature of CBA and SCBA, an increase in compressive and splitting tensile strengths were seen for specific concrete mixtures, and further addition of CBA and SCBA, the decrease in strength. The embodied carbon of SCBA has augmented the total embodied carbon of concrete, though it can be seen that C15S40, which comprises of 15% CBA and 40% SCBA, is the optimum mix that attained tensile and compressive strength by 3.05MPa and 28.75MPa correspondingly, with a 4% reduction in total embodied carbon.

The synergistic effect of hybridizing and aligning graphene oxide nanoplatelets and multi-walled carbon nanotubes on mode-I fracture behavior of nanocomposite adhesive joints

The synergistic effect of hybridizing and aligning graphene oxide nanoplatelet (GONP) and multi-walled carbon nanotube (MWCNT) on the mode-I fracture response of glass fiber/epoxy nanocomposite adhesive was studied. Different mixtures of nanofillers with aligned and random orientations and different mixing ratios and weight percentages were used for fabricating the reinforced nanocomposite adhesive joints. The results showed that the hybridization of MWCNTs and GONPs can considerably enhance the fracture behavior of nanocomposite adhesive joints providing that the appropriate hybrid ratio and weight percentage (wt%) were employed. It was found out that hybridizing one-third GONPs and two-thirds MWCNTs with 0.3 total nanofiller wt% caused 90% further improvement in the fracture energy of adhesive compared to the adhesive reinforced with merely MWCNTs at the same total nanofiller wt%. Furthermore, aligning nanofillers with electrical field resulted in more than twice the higher enhancement in the fracture energy of adhesive. Moreover, assessing the fracture surfaces of the unreinforced and reinforced specimens revealed that the type of reinforcement can affect the failure pattern of the adhesive joints.

CONCRETE PROPERTIES EVALUATED BY REPLACING CEMENT WITH ALCCOFINE

Nowadays, many research works are being conducted throughout the world to develop cementitious materials that can replace cement. As a replacement for cement in concrete, fly ash, silica fume, GGBS, Metakaolin, Micro materials, Quartz powder, etc. are tried out in that order. This experiment tries out a new ultrafine material called Alccofine for a partial replacement. This concrete grade, M40, was developed for testing the cementing efficiency of Alccofine with a variety of percentages of replacement of cement with Alccofine, such as 5%, 10%, 15%, and 20%. A design mix has been developed for M40 grade and cubes have been cast with varying percentages of alccofine, as described above. A discussion of the results has been provided. Compared to other mix percentages, 15% of alccofine replacement with cement produces good strength. The SEM images show that Alccofine is found to have good cementing efficiency in earlier ages of concrete.

A Chaotic Encryption System Based on DNA Coding Using a Deep Neural Network

Critical to computer vision applications, deep learning demands a massive volume of training data for great performance. However, encrypting the sensitive information in a photograph is fraught with difficulty, despite rapid technological advancements. The Advanced Encryption System (AES) is the bedrock of classical encryption technologies. The Data Encryption Standard (DES) has low sensitivity, with weak anti-hacking capabilities. In a chaotic encryption system, a chaotic logistic map is employed to generate a key double logistic sequence, and deoxyribonucleic acid (DNA) matrices are created by DNA coding. The XOR operation is carried out between the DNA sequence matrix and the key matrix. Finally, the DNA matrix is decoded to obtain an encrypted image. Given that encrypted images are susceptible to attacks, a rapid and efficient Convolutional Neural Network (CNN) denoiser is used that enhances the robustness of the algorithm by maximizing the resolution of rebuilt images. The use of a key mixing percentage factor gives the proposed system vast key space and great key sensitivity. Its implementation is examined using statistical techniques such as histogram analysis, information entropy, key space analysis and key sensitivity. Experiments have shown that the suggested system is secure and robust to statistical and noise attacks.

Ratio of Mixed Venous Oxygen Saturation-to-Pulmonary Capillary Wedge Pressure: Insights From the Veterans Affairs Clinical Assessment, Reporting, and Tracking Program.

Hemodynamic values from right heart catheterization aid diagnosis and clinical decision-making but may not predict outcomes. Mixed venous oxygen saturation percentage and pulmonary capillary wedge pressure relate to cardiac output and congestion, respectively. We theorized that a novel, simple ratio of these measurements could estimate cardiovascular prognosis. We queried Veterans Affairs' databases for clinical, hemodynamic, and outcome data. Using the index right heart catheterization between 2010 and 2016, we calculated the ratio of mixed venous oxygen saturation-to-pulmonary capillary wedge pressure, termed ratio of saturation-to-wedge (RSW). The primary outcome was time to all-cause mortality; secondary outcome was 1-year urgent heart failure presentation. Patients were stratified into quartiles of RSW, Fick cardiac index (CI), thermodilution CI, and pulmonary capillary wedge pressure alone. Kaplan-Meier curves and Cox proportional hazards models related comparators with outcomes. Of 12 019 patients meeting inclusion criteria, 9826 had values to calculate RSW (median 4.00, interquartile range, 2.67-6.05). Kaplan-Meier curves showed early, sustained separation by RSW strata. Cox modeling estimated that increasing RSW by 50% decreases mortality hazard by 19% (estimated hazard ratio, 0.81 [95% CI, 0.79-0.83], P<0.001) and secondary outcome hazard by 28% (hazard ratio, 0.72 [95% CI, 0.70-0.74], P<0.001). Among the 3793 patients with data for all comparators, Cox models showed RSW best associated with outcomes (by both C statistics and Bayes factors). Furthermore, pulmonary capillary wedge pressure was superior to thermodilution CI and Fick CI. Multivariable adjustment attenuated without eliminating the association of RSW with outcomes. In a large national database, RSW was superior to conventional right heart catheterization indices at assessing risk of mortality and urgent heart failure presentation. This simple calculation with routine data may contribute to clinical decision-making in this population.

Fabrication of novel microreactors in-house and their performance analysis via continuous production of biodiesel

Microreactors enhance biodiesel yields due to their more efficient mixing mechanisms and faster mass transfer rates than conventional batch processes. In this investigation, microreactors with different designs and geometries (four T-shaped with different lengths, one Y-shaped, and one Tesla-shaped) have been successfully fabricated at Fab Lab Bahrain using a high-resolution CO2 laser cutting machine. Then, the performances of these microreactors for the continuous production of biodiesel were tested and compared. The transesterification of the 9:1 molar ratio of methanol to oil was operated at a temperature of 60°C, with a 1.0 wt% NaOH catalyst. The performance of each microreactor for biodiesel synthesis was experimentally studied. The highest biodiesel yield was found to be 97.9%, with the Tesla-shaped microreactor at a residence time of only 4.85s, while the T- and Y- shaped microreactors give the highest percentage yield of 93.3% and 94.3%, respectively, with a residence time of 3.28s each. Online monitoring of the microchannel using optical imaging showed a mixing percentage of 97.6%, 97.87%, and 99.52% with T-, Y-, and Tesla- shaped microreactors, respectively, which consolidates the mixing effect's on developing the percentage yield of biodiesel.

Study of electrohydrodynamic properties in insulating liquids and research of an alternative mixture to mineral oil for energy transformers

The article discusses, the electro-hydrodynamic phenomenon of three types of insulating oil, one mineral and two vegetable (olive oil and corn oil) and their mixtures in terms of aging time. The experimental results, allowing us the determination of the initiation and the development of electro-convection voltage of different insulating oils.A very important results was obtained, concerning the relaxation time of the insulating liquid after the appearance of its movement under the effect of the electric field. The analyzed physicochemical properties of different insulating liquids were: viscosity, resistivity, conductivity, breakdown voltage and dissipation factor, all carried out and compared by means of measurements. A close correlation between the flexibility of liquid dielectrics in movement in an electric field and their susceptibility to static electrification is approved. It appears from the various tests carried out that the optimal mixture obtained consists of 60% naphthenic mineral oil and 40% olive oil. The respect of these percentages of mixtures has made it possible to improve some characteristics of this insulating liquid and to keep the good properties possessed by naphthenic mineral oil. From the recorded observations, We have found that this mixing percentage also leads to the reduction of turbulent movements which can participate in the fight against the breakdown of energy transformers.

Bending Behaviour of Concrete Beams with Composite Reinforcement

Massive quantities of finite resources have been depleted due to the construction and building sectors. Using bio-products to reduce raw materials use is seen as a major step toward a sustainable building sector. In this regard, the current research developed a novel composite beam reinforced and double-confined using a flexural and shears continuous FRP-Jacket. The suggested method involves swapping out conventional Portland cement-based concrete with a greener variant made with a different mix percentage that includes dry clay and hydraulic lime. Experimental testing and theoretical modeling based on shear stress and deformation composite beams are used to assess the bends &amp; shear performance of the suggested design with four-point flexural load. The double-confinement approach used resulted in a noticeable improvement in strength and deformability compared to conventional concrete beams, as shown by strong agreement between experimental and modeling results in terms of effective stress, pressure concentration, and cement reduction.

Mechanical and microstructural properties of quaternary binder system containing OPC-GGBS-Metakaolin-Lime

Due to the massive amount of cement manufactured its widespread use as a binder leads to global warming, which can be mitigated by substituting supplementary cementitious material for cement. This experimental study describes the characteristics of a stable and high strength quaternary binder matrix made up of Ground Granulated Blast Furnace Slag (GGBS), Metakaolin (MK) and lime powder. The quaternary binder system is a combination of GGBS ranges from 30 to 40 %, Metakaolin varies from 5 to 15% and 5% of lime powder at a constant rate. At 3,7,14, and 28 days of curing, hardened paste specimens were tested for compressive strength by IS516 (1964). Microstructural properties of 7 and 28 days cured samples were studied using analytical techniques such as X-Ray Diffraction (XRD) and Fourier transform infrared spectroscopy (FTIR). The test sample of the highest percentage of GGBS mix obtained the greatest compressive strength of 54.13 MPa at 28 days of curing.

Effect of B4C particle reinforcement on tensile properties of Al7075/B4C composites

The tensile properties of the composite materials are of most interest in the application of composite materials in specific environment. The production of composite material plays an important part in deciding the mechanical properties of the composite material. The process parameters selected during the manufacturing of composite material decides the tensile properties of the material. This work is oriented towards developing a new composite material with Aluminium 7075 as the matrix material and reinforcing it with boron carbide as the reinforcing material. The reinforcement substantial is varied in weight percentage and the tensile strength is studied at different compositions for better results. High purity Al7075 is reinforced with 5%, 10% and 15% weight with commercial grade boron carbide. The results demonstrate that the B4C particulates are dispersed in Al7075 matrix phase. With increasing reinforcement weight fraction, tensile strength decreases initially and increases. From ANOVA it has been found that mixing time and B4C weight percentage have more influence on tensile strength. Maximum tensile strength obtained at mixing time of 9 min, B4C weight percent of 15% and with reinforcement particle size of 9 mm.

Interpretation of the performance and emission characteristics of a CI engine running on ethanol-butanol diesel blends using an optimisation model

Every nation is attempting to minimise pollution in a variety of ways as government's upcoming laws and bills on emissions mitigation have sped up engine development. Our research's goal is to investigate alternative optimisation models for emission and performance to find the optimal ethanol-butanol diesel blends. This research looked at CO, CO2, NOx, and HC levels as emission parameters. Minor variations in the performance metrics like brake thermal efficiency (BTE), brake power, torque, and mechanical efficiency were recorded. It was evident from the graphs that the performance characteristics were slightly higher than neat diesel and except for the amount of unburned hydrocarbon, there has been a substantial improvement in emission characteristics. The goal of optimisation is to find the best alcohol diesel mix percentage that can be utilised in a diesel engine. The ideal mix is chosen based on the desirability value derived from the optimisation data.

Experimental Study on Mechanical Properties of Concrete by partial replacement of Cement with Eggshell Powder for Sustainable Construction

Oman has made tremendous progress in establishing road infrastructure to enable industrial expansion in the age of globalization. As an oil-dependent economy, Oman's Vision 2040 asks for the construction of multiple power projects, greater manufacturing capacity, the expansion of the building industry, and a range of other infrastructures. As a consequence, it is clear that the success of a state is based not only on technological growth, but also on well-developed physical infrastructure. Despite the fact that concrete enterprises contributed to carbon emissions, a key component in environmental deterioration, and concrete industry waste contributed to global warming. During the last decade, substantial study has been conducted on waste management in the concrete sector. Effective bio-waste disposal has become more vital in our society for both environmental and economic reasons. Eggshell recovery from hatcheries, residences, bakeries, and businesses is a low-cost and efficient way to reduce waste disposal and avoid serious pollution. Egg shell garbage contains both organic and inorganic components that can be composted with other materials to improve the qualities of pre-existing products. The main objective of every civil sector is effective construction at a reasonable cost. The goal of this research is to evaluate the impact of eggshell powder as a partial replacement material of cement in concrete manufacturing. Eggshell powder is partially replaced as various proportions, such as 5, 10, 15 and 20 percentages, has been utilized as a substitute for conventional Portland cement in a design mix percentage in standard concrete of grade M 25. According to the findings, the concrete considerable improvement was noticed in the compressive and flexural strength of concrete. Furthermore, according to the data analysis from this experiment, the optimal proportion of oven-dried eggshell powder as a partial cement alternative is 10%.

Optoelectronic properties and Effect of annealing on structural of Zn mixed CdS thin film by SILAR method

In this research, the zinc mixed cadmium sulfide thin films were synthesized on the glass substrate by simple and easy successive ionic layer adsorption and reaction (SILAR) process. The thin films were prepared by different mixing percentage of Zinc with cadmium sulfide. The Zn-CdS films have been characterized by X-Ray diffraction (XRD), field-emission scanning electron microscopy (FESEM) and optical properties were investigated by ultraviolet-visible spectrophotometer. X-Ray studies show the hexagonal crystal structure of CdS film. The surface morphology is found different in both annealed and unannealed structure from FESEM image. It is smooth, dense and uniform in structure in case of unannealed condition. And it is non-uniform structure when annealed. The absorbance spectra of pure CdS and Zn mixed CdS has compared and it is observed that Zn-mixed CdS have greater absorbance than pure CdS.

Behaviour of concrete by partial replacement of fine aggregate with eco sand

Within the current period, an outsized quantity of concrete construction activities is happening. Natural sand (river sand) which is the key ingredient of concrete is changing into demand and high-ticket. Factory-made sand may be substitute of concrete construction which has been produced from crushing laborious batholite rock. Eco-Sand which is a by-product from cement manufacturing. The entire study deals with the behaviour of concrete by replacing sand with eco sand. The traditional watercourse sand is replaced with M sand an in this study factory made sand is replaced by Eco-Sand at numerous percentages like 6%, 12%, 18%, 24%& 30% in PCC. It's valued that the optimum replacement shares of Factory-made Sand by Eco-Sand and also the properties of contemporary concrete, laborious concrete in PCC with Eco-Sand. Most scope of this study is to cut back the pollution and environmentally friendly. Varied test provides that eighteen percentages as the optimum percentage of the current mix of the factory made sand and Eco-sand.

Pengaruh Penggunaan Zat Aditif Minyak Cengkeh Terhadap Prestasi Mesin Sepeda Motor Injeksi 4 Langkah

At this time, fuel oil has become a basic need by the Indonesian people due to the increase in the use of vehicles, while the government is still subsidizing fuel oil. For this reason, it is necessary to save on the use of fuel oil. The alternative that can be done is reformulating fuel oil with additives that function to enrich the oxygen content in the fuel. The purpose of this study is to determine the performance of the engine which can be seen from the fuel consumption and acceleration of the vehicle in which the percentage of clove oil mixing which is most effective in its use will be known. This research includes mixing 1.5%, 2.5%, 3.5% and 4.5% mixture of clove oil to premium/gasoline. In this study, the formulation of a premium fuel/gasoline mixture with clove oil was most effective and efficient on fuel consumption, namely in the stationary test it was a mixture of 1.5% while in the running test it was a mixture of 2.5%. For the acceleration test, the best mixing formulation is in the 4.5% mixture formulation, both in the 0-70 km and 40-70 km tests.

Performance and environment interactivity of concentric heat exchanger practicing TiO2 nanofluid and operated near heat capacity ratio of unity

The present research aims to experimentally investigate the influence of mixing Titanium Oxide nanoparticle with distilled water on the performance and energy-environment interrelation of a concentric heat exchanger at variable cold/hot flowrate ratio and mixing percentage. The target parameters of interest include the heat capacity ratio (the flowrate ratio), the overall heat transfer coefficient, the NTU-value, the exchanger effectiveness, and the heat leak to the surrounding. Results of the study show that significant drops in the NTU-value is observed when the heat capacity ratio approaches unity, albeit noticeable enhancement in the overall heat transfer unit is discerned. Such reduction results in a 25%–29% decrease in the effectiveness of the exchanger for the range of nanofluid volume fraction selected. Heat leak factor is observed to perpetually descend with the increase in the heat capacity ratio for all volume concentration of nanofluid, including the pure water case, suggesting that this factor is apparently dominated by Reynolds number rather than capacity ratio.The enhancement in the effectiveness caused by switching the configuration from parallel to counter profile ameliorates by ∼16.5% up to ∼25.5%. In return, the heat leak factor reduces by a range of 47%–60% for the same domain of nanofluid volume fraction.

Indonesia’s Road to Fulfill National Renewable Energy Plan Target in 2025 and 2050: Current Progress, Challenges, and Management Recommendations – A Small Review

Indonesia has a large amount of energy consumption, domestically and industrially. Indonesia’s energy mix is still dominated by fossil fuels and coals, with the percentage of 35.64% and 50% respectively in 2020. This is caused by Indonesia’s rich supply of oil and coal, even though experts have predicted that these supplies will run out in 10 years ahead. One option to preserve Indonesia’s energy security is to start using renewable energy. Indonesia’s renewable energy potential is predicted to be around 443 GW of installed capacity, and already made renewable energy mix percentage target of 23% in 2025 and 31% in 2050 in their National Energy Plan. However, Indonesia’s renewable energy percentage in their 2020 national energy mix is only 14.71%. Therefore, to reach their national renewable energy target, Indonesia needs to solve their problems by finding the right actions and strategies in their energy management through stakeholders such as the government, public, and investors. This review will be made by using the literature based research method.

Effect of oxygen mixing percentage on structural, optical and electrical properties of ZnTiO3 thin films grown by RF magnetron sputtering

Perovskites are important composites in the area of multidisciplinary applications. The enhancement in properties of the composite can be achieved by carefully choosing and tuning the properties of the thin film at the deposition. In this paper, ZnTiO3 thin films were deposited on quartz and N-Si substrates at various oxygen mixing percentages (OMP) from 0 to 100% using RF magnetron sputtering technique. The deposited thin films were annealed at 600 °C for 1h and confirmed the cubic perovskite structure of ZnTiO3. The roughness value of the thin film is (0.25–0.74 nm) < 1 nm and it is identified from the atomic force microscope. The optical properties of ZnTiO3 thin film indicated the highest refractive index of 2.46, at 633 nm with optical bandgap values of 3.57 eV, with a thickness of 145 nm and 25 OMP. Electrical characteristics of ZnTiO3 thin film measured from the conventional thermionic emission technique are: reverse saturation current I0 is 5.83 × 10–11 A, Barrier efficiency ϕB,eff is 0.87 eV, and Ideality factor η is 2.35.