Definite Proportions Research Articles

A systematic analysis of binary blend cement concrete infused with lime sludge and fly ash

Lime sludge is a residual substance came from the paper sector. The current research investigates that the effects of adding lime sludge to concrete as a cementitious substance on its mechanical properties. Lime sludge replaces cement in various amounts to provide the appropriate mechanical properties. The resulting material is then compared to standard concrete. The research on supplemental cementation resources that equivalent Portland cements's potency without compromising stability. According to the Indian standard (IS 10262–2009), the study used M20, M30, and M40 concrete. Lime sludge replaced cement 0 ​%, 10 ​%, 20 ​%, and 30 ​%. Also investigated were lime sludge and fly ash mixtures of 10 ​%, 20 ​%, and 30 ​% by weight. Mechanical parameters of concrete classes M20, M30, and M40 were measured at 7 and 28 days. The grades show that the 10 ​% lime sludge out performed normal concrete. This work represents can be applied as unique additional cementitious substance up to the definite proportions.

Integration of FDM and self-healing technology: evaluation of crack sealing by durability and mechanical strength

The tensile zone of concrete is prone to cracking due to its limited ability to withstand tension. To address this issue, steel reinforcement is used in these specific regions. The occurrence of little cracks might potentially facilitate the ingress of liquids and gases into the reinforcing material, hence inducing corrosion. Self-healing concrete can repair and seal minuscule cracks, thus impeding the formation of corrosion. This study investigates the potential application of fused deposition modeling (FDM) for generating novel vascular networks and tubes using polylactic acid (PLA) as the material. Poly (lactic acid) (PLA) was fabricated using three-dimensional (3D) printing techniques, and its properties were compared to those of one-dimensional (1D) and two-dimensional (2D) networks. The external diameter measured 5.6 mm, while the internal diameter measured 4 mm. utilized a 10 ml volume to apply healing agents, specifically organic polyethylene glycol liquid and nano-powder (fly ash) derived from recycled materials, to all vascular structures (1D, 2D, and 3D). This application was carried out using a planetary ball mill. Following this, the prepared tubes were incorporated into a concrete beam to introduce self-healing capabilities. The water-to-cement ratio (W/C) utilized for all concrete mixtures was 0.6%, while the definite mixture proportions were 1:2.16:2.98. The quantification of the self-healing phenomenon was conducted by evaluating the restoration of load-carrying capacity following the application of a repaired specimen to a four-point bending test. Furthermore, these enhancements resulted in improved durability, increased compressive strength, and enhanced other physical characteristics. The pipes that are manufactured can be utilized to produce innovative concrete that possesses the ability to undergo self-healing processes by combining low-viscosity healing solutions (PEG) with powders (nano fly ash) that are appropriate for this application by injection into the vascular network , making it well-suited for various self-healing applications.

Characteristics and Antioxidant Activities of Three ‘Beras Kencur’ Effervescent Formulations

This study aimed to evaluate the physical characteristics and antioxidant activities of beras kencur effervescent tablet formulations. Beras kencur was prepared in 7 different concentrations to assess the percent inhibition. The highest inhibition potency (76.2%) was found in beras kencur 10 mg/mL. This concentration was used to obtain the formulation of the effervescent tablet, which differed in definite proportions of citric acid (C6H8O7), tartaric acid (C4H6O6), and sodium bicarbonate (NaHCO3). When dispersed in water, the tablet produces a bubbling reaction by releasing CO2. The tablets were evaluated for pH, soluble time, total phenolic content (TPC), and antioxidant activity. These observations demonstrated that the higher proportion of NaHCO3 led to the higher solubility of the effervescent tablet. The antioxidant activity of formulations was evaluated using a 2,2-diphenyl-1-picrylhydrazyl (DPPH) assay and total phenolic content was determined using Folin-Ciocalteau. The outcomes suggested that the phenolics might become unstable at high acid conditions. In contrast, an increase in alkaline pH increased the ability of effervescent tablets to produce reactive oxygen species (ROS). The tablet with an equal proportion of acid and base showed the highest antioxidant activity (IC50 = 20.8), in line with the total phenolic content (5.772 mg GAE/mL).

Structural performance of Nano alumina-based RC element with polypropylene fibre and GGBS: An experimental assessment

In today's scenario, the essential ingredients of concrete, such as cement, and fine and coarse aggregate will vanish completely in a few decades due to its overexploitation and unscaled utilization. Similarly, cement has contributed to more emissions of carbon dioxide into the atmosphere during its stage of manufacturing, and it’s become a major influencer of increasing global temperatures. Recent researchers are finding alternative sources of materials that replace fully or partially the role of conventional concrete materials. Several industrial and agricultural solid residues are under investigation to be utilised nowadays to alter the place of conventional concrete materials and to control the impact of environmental problems. In this study, the performance of structural RC elements of M35 grade was evaluated by replacing the Nano alumina in a fixed proportion of 1% with the inclusion of ground granulated blast furnace slag and Polypropylene fibre at definite proportions in place of cement as per mix design. Engineering parameters such as compression, modulus of rupture and elasticity, crack width, and rate of deflection was examined. Based on the results of experiments, it was found that the cement proportion CAG1 and CAGP4 have provided the promotable result when compared to conventional concrete and led to using these materials instead of cement has made RC elements stronger than when they were made with regular cement.

What programs the size of animal cells?

The human body is programmed with definite quantities, magnitudes, and proportions. At the microscopic level, such definite sizes manifest in individual cells - different cell types are characterized by distinct cell sizes whereas cells of the same type are highly uniform in size. How do cells in a population maintain uniformity in cell size, and how are changes in target size programmed? A convergence of recent and historical studies suggest - just as a thermostat maintains room temperature - the size of proliferating animal cells is similarly maintained by homeostatic mechanisms. In this review, we first summarize old and new literature on the existence of cell size checkpoints, then discuss additional advances in the study of size homeostasis that involve feedback regulation of cellular growth rate. We further discuss recent progress on the molecules that underlie cell size checkpoints and mechanisms that specify target size setpoints. Lastly, we discuss a less-well explored teleological question: why does cell size matter and what is the functional importance of cell size control?

Optimization and effect of B4C/Al2O3 with graphite particulates on tribological properties of Al7075 surface hybrid nanocomposite

Aluminium alloy surface hybrid nanocomposite, reinforced with boron carbide (B4C), aluminium oxide (Al2O3), and Graphite (Gr) at different combination mixtures by weight ratio have been fabricated on Al7075-T6 aluminium plate by employing friction stir processing (FSP). The mixtures of definite proportions were packed in an array of blind holes 2.5 mm in diameter and 3 mm deep which are 6 mm apart from each other. FSP was done with processing factors of 750 rpm revolving speed, 20 mm min−1 feed, and tool angle of 3°. The prepared hybrid composites were sectioned for microstructure, macrostructure, wear, and hardness evaluation. In the metal matrix surface composite, the scanning electron microscope (SEM) and field emission scanning electron microscope (FESEM) depict the homogeneity in the distribution of reinforcement elements, microstructure, and wear behaviour. Under dry sliding conditions, the nanocomposite’s wear behaviour was investigated by adopting a central composite design (CCD) at 3 levels in response surface methodology (RSM) for optimization. The wear characteristics are analyzed using pin on disc apparatus. The wear property of the nanocomposites with distinct reinforcement ratios was evaluated. Higher hardness values (maximum of 191 Hv) were found in hybrid nanocomposite samples than in the plain FSPed samples (149Hv) without reinforcement. It is evident, that the wear loss depends on the relative weight ratio of B4C and Al2O3 with a constant amount of graphite and the minimum wear loss of 2.9421 mm3 is obtained from composite with 30 B4C + 60 Al2O3+10 Gr reinforcement ratio than the wear loss of 8.2292 mm3 obtained from plain FSPed composite. The optimal combination of parameters, Al2O3 60%, load 20 N, and velocity 1 m s−1 was identified from RSM. The hybrid nanocomposite having a reinforcement mixture of 30 B4C + 60 Al2O3 + 10 Gr exhibits a significant wear resistance than other combination ratios. This is endorsed by the enhancement in binding strength of the matrix and the pinning effect of hard reinforcements, which act against the applied shear force.

The Effect of Surfactant on Polyherbal Liquid Shampoo and its Comparative Analysis

Objective: Herbal shampoo is gaining immense popularity among all consumer groups due to rising awareness about the side effects of chemical formulations. It was also observed that not many marketed shampoos incorporated excellent hair nurturing properties of curry leaves. The aim of the study was to formulate and evaluate herbal shampoo using Murraya koenigii, Phyllanthus emblica, Acacia concinna Linn., Trigonella foenum-graecum, Sapindus mukorossi and perform a comparative analysis with marketed formulation. Method: Three formulations were prepared using extracts of Murraya koenigii, Phyllanthus emblica, Acacia concinna, Trigonella foenum-graecum and Sapindus mukorossi in definite proportions. Decyl Glucoside and Sodium Lauryl Sulphate were added as surfactant in adequate amount. The formulated shampoo was evaluated for organoleptic properties (colour and odour), pH, surface tension, viscosity, dirt dispersion, cleansing action, foaming ability and stability studies. Results: The formulated shampoos were brown in colour with good acceptable fragrance. All the formulations showed good cleansing and detergency power with stable foam. F1 showed comparatively better foaming ability. All the formulations had neutral pH and low surface tension (21-25 dyn/cm). The solid content was found to be in the range of 23-27 % and viscosity 4885 cP- 4903 cP. The results of the prepared formulations were compared with a marketed formulation and were found that F1 formulation was on par with marketed formulation. Conclusion: The prepared shampoo had good characteristics. It was further inferred that it is possible to develop safer and equally effective shampoo using ingredients of plant origin.

Confinement effects on C–H and C–F stretching vibrational frequencies of difluoromethane in cold inert gas matrixes: a combined infrared spectroscopy and electronic structure theory study

Mid-infrared spectra of difluoromethane (DFM) have been recorded by confining the molecule in the matrix cages of pure argon, nitrogen and in the mixed matrixes of argon and nitrogen obtained by mixing the two gases in definite proportions. The measured spectra depict distinct confinement effects in terms of the infrared spectral shifts of the C–H and C–F stretching vibrational fundamentals as compared to the free molecules in the gas-phase, and also some remarkable changes in band appearances and relative intensities. The signs of the spectral shifts are observed to be different for the $$\upnu _{\text {C--H}}$$ and $$\upnu _{\text {C--F}}$$ transitions. Pronounced blue shifts are observed for the two $$\upnu _{\text {C--H}}$$ modes in pure nitrogen matrix, which progressively reduce in magnitude in the mixed matrixes, and is least in the pure argon matrix. On the other hand, distinct red shifts of the $$\upnu _{\text {C--F}}$$ vibrations are evident in pure nitrogen matrix, which are reduced in magnitude in the mixed matrixes, and become even less pronounced in pure argon matrix. The effect of Fermi resonances in the $$\upnu _{\text {C--H}}$$ region, that has motivated several previous investigations of DFM including high resolution gas phase studies, becomes explicit upon comparison of the matrix isolation spectrum with the gas phase spectrum. Electronic structure calculations using several DFT and DFT-D methods, in conjunction with NBO analysis, have been carried out for various sizes of $$\hbox {DFM-N}_{2}$$ and DFM-Ar complexes in order to understand the underlying interactions responsible for the observed shifts. The calculations are found to satisfactorily reproduce the observed variations in magnitude and direction of the shifts of both the $$\upnu _{\text {C--H}}$$ and $$\upnu _{\text {C--F}}$$ transitions for the change of the medium. It is inferred that the inert gas matrix environment exerts an electronic re-organization within the DFM molecule, and the consequent rehybridization of the carbon-centric hybrid orbital of the C–H and C–F bonds is responsible for the observed spectral shifts.

Concrete Mix Design by IS, ACI and BS Methods: A Comparative Analysis

Concrete is one of the most consumable construction materials on the earth. The concrete constitutes cement, sand, gravel, water and/or additives in definite proportions. The proportions of raw materials of concrete are decided by the concrete mix design. The mix design depends on the various factors. For mix design, most of the countries have their own specifications. In the present study, standard guidelines of India, Britain and America for the concrete mix design have been discussed. The concrete grades of M25, M35 and M45 were designed and compared. Indian Standards were also compared. It was concluded that new revised version of Indian Standard code has the lowest value of water/cement ratio and highest quantity of cement as compared to other standards.

Fe–TiO 2 composite beads driven hybrid process of photocatalysis and photo-Fenton for the degradation of isoproturon

The concept of hybrid process of photo-Fenton and photocatalysis, particularly in the fixed mode, has been presented in this study for the degradation of the pesticide isoproturon with reduction at the time of treatment. For fixed-bed studies, spherical beads were prepared by combining definite proportions of clay, foundry sand, and fly ash, which were utilized as iron sources for titanium dioxide (TiO2) immobilization. The optimization of various parameters was performed by utilizing the Box–Behnken design model under response surface methodology. The process of degradation followed first-order kinetics under an optimized condition for the integrated degradation of isoproturon with a 700 mg·L-1 dose of H2O2, 42 spherical beads, and 190 mL of solution for a duration of 176 min at pH 3.7. Approximately 80.96% degradation of isoproturon was observed after inducing the optimized conditions. The integrated treatment was also carried out in a solar batch reactor under optimized conditions to expand its application to industries for treating bio-recalcitrant compounds. The mineralization of isoproturon was confirmed through the generation of nitrate, nitrite, and ammonical nitrogen with a definite chemical oxygen demand reduction. The recyclability of the catalyst was confirmed by recycling the spherical beads characterized by scanning electron microscopy–energy dispersive X-Ray analysis. For confirming the dual effect, that is, the presence of TiO2 along with Fe on the bead’s surface, various analyses including UV–diffuse reflectance spectroscopy, scanning electron microscopy–energy-dispersive spectroscopy, X-ray diffraction, and Fourier-transform infrared spectroscopy were carried out. A tentative pathway for isoproturon removal was also predicted based on intermediate analysis through gas chromatography–mass spectroscopy.

Liquid Metals in Catalysis for Energy Applications

Summary To keep up with the fast-paced transitioning of the global energy sector, which is constantly thriving to enable reliable, economic, and sustainable energy production, catalysis research has been required to continuously evolve in response. The challenges in the existing systems are predominantly due to dependencies on heterogeneous solid catalysts that are susceptible to coking. In this respect, liquid-metal (LM) catalysts have been demonstrated to have a critical advantage over conventional catalysts. Recently, LMs acquired a place in catalysis, with a reputation often synonymous with interesting properties and a remarkable ability to break trade-offs between homogeneous and heterogeneous catalysis. This review bridges the fundamental principles of LM research and the recent advances in LM-based thermal and electrochemical catalysis for energy applications. Moreover, emerging approaches for the improved utilization of LMs are outlined, and the concepts requiring greater research attention that could enable the development of exciting energy solutions are highlighted.

Role of Type2 Inflammatory Biomarkers in Chronic Obstructive Pulmonary Disease.

Airway inflammation in chronic obstructive pulmonary disease (COPD) is typically thought to be driven by Type1 immune responses, while Type2 inflammation appears to be present in definite proportions in the stable state and during exacerbations. In fact, some COPD patients showed gene expression of Type2 inflammation in the airway, and this subset was associated with the inhaled corticosteroid (ICS) response. Interestingly enough, the relationship between COPD and diseases associated with Type2 inflammation from the perspective of impaired lung development is increasingly highlighted by recent epidemiologic studies on the origin of COPD. Therefore, many researchers have shown an interest in the prevalence and the role of existent Type2 biomarkers such as sputum and blood eosinophils, exhaled nitric oxide fraction, and atopy, not only in asthma but also in COPD. Although the evidence about Type2 biomarkers in COPD is inconsistent and less robust, Type2 biomarkers have shown some potential when analyzing various clinical outcomes or therapeutic response to ICS. In this article, we review the existent and emerging Type2 biomarkers with clinically higher applicability in the management of COPD.

Synthesis and Iodometric Analysis of the Polyiodide Salt (NMe4)[I5

This paper describes a first-year undergraduate exercise involving the synthesis of an “unknown” polyiodide salt, (NMe4)[I5], and the determination of its formula using the classic iodine–thiosulfate (iodometric) titration. The exercise introduces students to simple synthetic and titrimetric techniques, assists the development of their chemical and glassware handling and titrimetric skills, and acquaints them with unfamiliar polyiodide compounds. It also introduces students to key chemical concepts such as The Law of Definite Proportions, percentage elemental composition, empirical chemical formulas, quantitative stoichiometric reactions, and halogen catenation.

Enrichment of Biodiversity, Influence in Microbial Population Dynamics of Soil and Nutrient Utilization in Cereal-Legume Intercropping Systems: A Review

Intercropping system, in general, is growing of two or more crops on the same piece of land simultaneously with a definite row proportions. However, it is very much important to ensure that component crops do not compete with each other for space, natural resources and nutrients. The combination of cereal and legume in intercropping provides a greater scope for minimizing the adverse impact of moisture and nutrient stress in addition to improving system productivity, soil health and ecosystem services. Significant enhancement of system productivity in intercropping can be obtained with enrichment of biodiversity due to cultivation of various crop species and thus encouraging pollinators and microorganisms to harbor in the crop field. Adoption of efficient intercropping system can influence the microbial population dynamics in the soil. Population and activity of N-fixing microorganisms and other beneficial micro flora and fauna are also increased by adoption of cereal-legume intercropping system. Besides, intercropping systems with cereal-legume combination are known to facilitate efficient utilization of nutrients by creating congenial environment. The article emphasizes above and belowground diversity and efficient utilization of nutrients in cereal-legume intercropping system.

Incorporation of vinyl silane and epoxy silane oligomer into 2-EHA-based polyacrylate latexes via mini-emulsion polymerization and investigation of pressure-sensitive adhesive properties on polar and nonpolar surfaces

Pressure-sensitive adhesives (PSAs) form a bond to various surfaces when a light pressure is applied. PSAs combine the ability of being sticky with elasticity at definite proportions regarding the application area. The adhesion and cohesion mechanisms are well defined as peel adhesion, loop tack and shear strength in the literature and can be adjusted according to the specific requirements. On the purpose of having high peel adhesion and loop tack values without sacrificing the shear strength, 2-ethylhexyl acrylate-based latexes have been synthesized via mini-emulsion polymerization and latexes with high surface area were obtained enabling interactive relation with polar and nonpolar surfaces. Two types of silane selected among the mostly used species in industry were employed to increase the intermolecular interactions and proposed an approach for the incorporation of said compounds referring to the increasing demand of silane utilization in industry. N-dodecyl mercaptan was used as both chain regulator to adjust the molecular weight and cosurfactant to have colloidally stable hydrophobic particles in mini-emulsion polymerization. The incorporation of vinyl silane predominately led to an increase in shear strength owing to chemical cross-linking between chains. Epoxy silane oligomer, on the other hand, increased the peel adhesion and loop tack values considerably compared to the case of vinyl silane. The type of silane incisively affects the PSA properties and should be taken into consideration while constructing a polymer for a pre-specified application. The assumptions in question were strongly correlated with peel, shear and loop tack values, cross-linking density, molecular weight and gas chromatography measurements.

Exploring the corrosion inhibition of magnesium by coatings: Formulated with nano CeO2 and ZnO particles

The objective of the work is to identify the anticorrosive property synthesized Nano ZnO rods and CeO2 particles. Both ZnO and CeO2 have good anticorrosion behavior; this materials are tested with and without composition to identify the corrosion inhibition behavior. The result reveals the high protection rate, which was accomplished by the composition. In this research, a detailed investigation of the corrosion inhibition performance of magnesium (Mg) substrate coated nanoparticles like cerium dioxide (CeO2), zinc oxide nanorods (ZnO) and CeO2/ZnO composites were studied. Synthesized nanoparticles were characterized by various physio-chemical techniques. Surface morphology of the developed set of specimens was scrutinized through SEM and EDAX, which established a clean surface coating with minimal defects attainment through doctor’s blade method. Electrochemical corrosion behavior of Mg substrates coated with definite proportions of CeO2, ZnO and CeO2/ZnO composites were conceded in 3.5 wt. % NaCl using Tafel polarization and electrochemical impedance spectroscopy. Thus the developed CeO2/ZnO composite coating exhibits icorr of 0.905 (A cm−2) and corrosion rate was 0.81 × 10−5 mpy better corrosion resistance compared to bare Mg or CeO2 or ZnO coatings.

Effect of sintering on mechanical property of SiC/B4C reinforced aluminum

In this study, SiC (silicon carbide) and B4C (boron carbide) added Al 7075 based composites were prepared at 40%, 20% and 10% reinforcement ratios. Using powder metallurgy, composite sample with 9 different structures were produced at 700 MPa pressing pressure, at 550 °C in 90, 120, 150 min applying three different sintering times. According to Archimedes principle, theoretical densities of composite samples were calculated. Then, the hardness measurements and transverse rupture tests were conducted. Lastly, wear tests were conducted using the Pin on Disc Method. Images of composite samples were taken at optical microscope and Scanning Electron Microscope (SEM), and the microstructures were examined. It was determined that increase in SiC and B4C reinforcement ratios decreased the fracture resistance. However, when every reinforcement ratio was evaluated separately, it was observed that increase in sintering time affected the fracture resistance positively. Increase in sintering time also increased the density values, and the hardening values and wear resistance decreased. Increase in reinforcement ratios and sintering time affected the composite wear behavior negatively. Increase in reinforcement ratio in composite structure decreased the density; however, hardening values increased. In conclusion, in such type of composites, reinforcement ratios in definite proportions (∼20%) affect mechanical features positively, and excess in that ratio affect mechanical features negatively. Especially 40% reinforcement ratio was high for such type of composites and was not suitable for mechanical features.

Synthesis and characterization of a sol-gel-derived zeolite prototype as a prospective hydrocracking catalyst

This paper deals with the preparation and evaluation of a zeolite prototype developed from an aluminosilicate precursor for its possible application as a hydrocracking catalyst. Aluminium nitrate and tetraethyl orthosilicate at definite proportions were the primary reagents for the gel synthesis. Nickel loading and stipulated post-synthesis treatment of the material are also addressed in this paper. The characteristics of the calcined aluminosilicate gel were estimated using X-ray diffraction (XRD), scanning electron microscope (SEM) study with energy dispersive spectroscopy (EDS), differential thermal analysis (DTA) with thermogravimetry (TG) and Fourier-transformed infrared spectroscopy (FTIR) at different temperatures. A preliminary laboratory-scale investigation of hydrocracking performance of this zeolite prototype was also conducted.

Effect of particle size distribution on rheology of high concentration limestone–water slurry for economic pipeline transportation

ABSTRACTThe preparation of high concentration slurry requires careful selection of particle size distribution to achieve the required rheological properties for economic and efficient pipeline transportation. In the present study, the maximum static settled concentration (CW-max) tests pertaining to limiting achievable concentration and rheological measurements were performed for limestone samples in the slurry concentration range of 60–78.5% by mass. The limestone samples with four distinct particle size ranges; i.e., <38, 38–90, 90–210, 210–300 µm were used to prepare five representative experimental samples by blending the fines (<38 µm) with other three coarse size ranges in definite mass proportions. The rheological behavior of the five limestone slurry samples with mono-modal, bimodal and multimodal packing characteristics indicated non-Newtonian flow behavior and fitted well to Bingham Plastic model in the concentration range of 60–78.5% by mass. The slurry samples with bimodal and multimodal packing characteristics indicated substantial reduction in slurry viscosity, yield stress and improved solids loading as compared to mono-modal one. The higher CW-max values obtained for the specific blended (fines with coarse) limestone slurry samples were attributed to the packing effect and was correlated to the ratio of surface to surface separation for the coarse particles (β) to the average fine particle size (d50-f) to achieve higher solids concentration. The reduction in slurry viscosity observed for the specific limestone samples was further substantiated by correlating the distribution modulus (ψ) derived from Farris theory. It may be inferred that these theoretical treatments correlating the experimental data can provide highly reliable guidance to the preparation of high concentration limestone slurry for economic pipeline transportation.

A Technical Design Approach to Soil Moisture Content Measurement

Soil moisture is an important type of data in many fields; ranging from agriculture to environmental monitoring. Three soil samples were collected at definite proportions to represent the three basic soil types (sandy, loamy and clay soils). The moisture contents of these soil samples were analyzed using the thermogravimetric method. This paper employed the use of PC-based soil moisture content measuring system in order to obtain accurate results. It works with the principle that there is an increase or decrease in soil conductivity as soil moisture increases or decreases respectively. The constructed prototype was used to test the three soil samples as well and the results were compared with that of the thermogravimetric method. The results gotten from this prototype shows the relationship between conductivity and moisture content of the soil. The system was well calibrated in order to get standard readings and conquer the problem of transistor amplification at the signal pick up stage. This therefore makes it possible to get fast an accurate results without wasting much time and energy.