bluuebunny/crossref_metadata_2025_split huggingface dataset:
Modelling and optimization of epoxy-PMMA microcapsule synthesis parameter: A response surface methodology approach
Authors: Akorede Abdulafeez Olayinka , Aliyu Adetutu O , Adebisi Adetayo Abdulmumin 
Published: August 2024

Abstract
The efficiency of self-healing microcapsule in restoring damages incurred by polymeric or composite materials is heavily dependent on modelling of encapsulation conditions to achieve optimized microcapsule with desired characteristics. This study modelled the effects of encapsulation conditions (core–shell ratio, agitation rate, and temperature) on the morphological, chemical, and thermal characteristics of epoxy-polymethylmethacrylate (epoxy-PMMA) microcapsules using response surface methodology (RSM). Epoxy-PMMA microcapsules were synthesized by encapsulating epoxy resin in polymethylmethacrylate (PMMA) at varied encapsulation conditions using solvent evaporation method. The morphology of the synthesized microcapsule using optical microscope (OP) revealed that the microcapsules are either mononuclear or irregular capsule types. The modelled effect showed that microcapsule percentage yield varied between 74.96 to 96.56%, was highly influenced by core–shell ratio and the effect of studied encapsulation conditions on percentage yield was best described by quadratic model. The core content of the microcapsules varied between 54.8 to 67.2%, observed to be highly influenced by both core–shell ratio and agitation rate which fit into linear model. The microcapsule average diameter was between 26 to 74 μm, highly influenced by agitation rate and fit linear model. Fourier transform infrared (FTIR) spectra of synthesized microcapsules revealed epoxy characteristic peak of C–O–C at 913 cm−1 and C–O-ph stretching at 1032 cm−1. C–O doublet of PMMA was observed at 1386 cm−1 and 1189 cm−1. Thermogravimetric analysis (TGA) of epoxy-PMMA microcapsule showed three stages of decomposition attributed to water evaporation, epoxy degradation, and PMMA shell degradation. Lastly, optimization process to achieve maximum yield, maximum core content and minimum capsule diameter was obtained with core–shell ratio of 1.5:3 and agitation rate of 1000 rpm at 40 °C. The synthesized epoxy-PMMA microcapsules exhibited chemical, thermal, morphological stability and the models can be optimized to achieve microcapsule with desired characteristics.
Exact cosmological solutions for a Chaplygin Gas in anisotropic petrov type D spacetimes in Eddington-inspired-Born-Infeld gravity: Dark Energy model
Authors: Djiodjo Seugmo Guichard , Jean Baptiste Patenou , Tadmon Calvin 
Published: August 2024

Abstract
We consider a Petrov Type D physical metric g, an auxiliary metric q and a Chaplygin Gas of pressure P in Eddington-inspired-Born-Infeld theory. From the Eddington-inspired-Born-Infeld-Chaplygin Gas equations, we first derive a system of second order nonlinear ordinary differential equations. Then, by a suitable change of variables, we arrive at a system of first order linear ordinary differential equations for the non-vanishing components of the pressure P, the physical metric g and the auxiliary metric q. Thanks to the superposition method, we collect an analytical solution for the nonlinear system obtained, which allows to retrieve new exact cosmological solutions for the model considered. By studying the Kretschmann invariant, we see that a singularity exists at the origin of the cosmic time. By the Kruskal-like coordinates, we conclude that this solution is the counterpart of the Friedman-Lemaître-Robertson-Walker spacetime in the Eddington-inspired-Born-Infeld theory. The Hubble and deceleration parameters in both directions of the physical metric g and the auxiliary metric q, as well as their behaviours over time, are also studied. The thermodynamic behaviour of the Chaplygin Gas model is investigated and, as a result, we show that the third-law of thermodynamics is verified. This means that the value of the entropy of the Chaplygin Gas in the perfect crystal state is zero at a temperature of zero Kelvin, which yields a determined value of the entropy and not an additive constant. Finally, we show that the solutions change asymptotically to the isotropic regime of expansion of Dark Energy. With this, we infer that the Chaplygin Gas can show a unified picture of Dark Energy and Dark Matter cooling during the expansion of the Universe.
Triple band self-decoupled MIMO antenna pair for 5G communication
Authors: Kansal Parul , Mandpura Anup Kumar , Kumar Narendra 
Published: August 2024

Abstract
A two port multiple input multiple output (MIMO) antenna with self-isolation is proposed for the application of fifth generation (5G) mobile phones. In this antenna, feeding ports that are inherently isolated across a bandwidth without the need for extra decoupling components directly excite the MIMO antenna. An approach involving the creation of common and differential modes utilizes a mode-cancellation technique to comprehensively understand the self-decoupling mechanism on a physical level. The proposed self-decoupled antenna pair exhibits about 22 dB isolation across the triple band 2.58 GHz to 2.84 GHz, 3.4 GHz to 3.9 GHz and 4.3 GHz to 4.6 GHz, respectively. According to the experimental findings, the proposed MIMO system may offer better than 22 dB isolation across all ports and a respectable level of overall gain 1.9 dBi, 3.77 dBi and 2.9 dBi across 2.58 GHz to 2.84 GHz, 3.4 GHz to 3.9 GHz and 4.3 GHz to 4.6 GHz. A suggested design method, with its advantages of self-decoupling, simple structure, high efficiency and triple band demonstrates amazing upcoming 5G highly integrated MIMO antennas for 5G devices.
Revisiting the concordance ΛCDM model using Gamma-Ray Bursts together with supernovae Ia and Planck data
Authors: Adil Shahnawaz A. , Dainotti Maria G. , Sen Anjan A. 
Published: August 2024

Abstract
The Hubble constant, H0, tension is the tension among the local probes, Supernovae Ia, and the Cosmic Microwave Background Radiation. This tension has persisted for decades and continues to puzzle the community. Here, we add intermediate redshift probes, such as Gamma-Ray Bursts (GRB) and Quasars (QS0s), to check if and to what extent these higher redshift probes can reduce this tension.
We use the three-dimensional fundamental plane relation among the prompt peak luminosity, the luminosity at the end of the plateau emission, and its rest frame duration. We find similar trend in GRB intrinsic parameters as previously seen in Pantheon-Plus intrinsic parameters. We find an apparent 3.14σ tension for the GRB intrinsic parameter b.
Indeed, this tension disappears and the parameters are actually compatible within 2.26σ. Another interesting point is that the 3D relation plays an important role in conjunction with Supernovae data with Pantheon Plus and that this apparent discrepancy shows the importance of the correction for selection biases and redshift evolution. The incorporation of redshift evolution correction results in a reduction of the GRB tension to 2.26σ when adjusting correction parameters. We envision that with more data this indication of tension will possibly disappear when the evolutionary parameters of GRBs are computed with increased precision.
The Optical Variability Properties of TeV Blazars
Authors: Su Zi-An , Yang Wen-Xin , Zeng Xiang-Tao , Ou Le-Jian , Li Ze-Lin , Yang Jiang-He , Fan Jun-Hui 
Published: August 2024

Abstract
Variability is one of the typical observational properties of blazars and the spectral changes are usually associated with variability, although this kind of association is unclear yet. In this work, we used data from the Steward Observatory blazar monitoring program to investigate the optical variability properties including the short-term timescale, the brightness-dependent spectral property, the correlation between the the brightness variation and the polarization, and then estimate the Doppler factors based on the obtained short timescale to study the polarization property for a sample of 20 TeV blazars. Our analyses arrive at the following results: (1) The largest variation amplitude in R-band, ΔR

M
, covers a range from ΔR

M
= 0.29 mag (1ES 2344+514) to ΔR

M
= 4.66 mag (3C 279). (2) Intra-day variability was found from five sources with timescales from 0.14 day for S5 0716+714 to 0.98 day for PKS 2155–304. Sixteen sources show spectra that are bluer when they become brighter, suggesting a common bluer-when-brighter property. (3) The plot of the polarization versus estimated Doppler factor is consistent with the Doppler factor dependent formula of polarization. (4) The largest polarization is correlated with the largest optical variation, suggesting that the high polarization and high amplitude variation are both the indicator of beaming effect.
Strength and Durability Performance of Fly Ash Concrete with and without Superplasticizer
Authors: Kanthe V.N. , Kulkarni T.A. , Padalkar P.A. , Pawar V.V. 
Published: August 2024

Abstract
In this study, the impact of Fly Ash (FA) with and without a superplasticizer (SP) on the characteristics of binary blend concrete has been documented. Ordinary Portland Cement (OPC) was substituted by 10 to 50% of FA. The assessment covered CS, workability, and the concrete’s resilience. The findings reveal that the most substantial Compressive Strength (CS) was attained using a 20% FA mix in binary concrete compared to the control mix (CM). Satisfactory outcomes were evident in durability assessments. FA with SP increases strength by 15.38% compared to the combination without SP. And for durability the reduction of water absorption percentages around 4% for FA blend concrete when SP is added compared to the blend without SP. Such concrete proves more active in boosting both mechanical and durability aspects while reducing cement usage. Employing industrial by-products renders concrete more sustainable and mitigates environmental concerns.
Safety analysis of selected zoned roller compacted concrete (ZRCC) gravity dam
Authors: Siva Parvathi I , Nadh Sri Vasthav 
Published: August 2024

Abstract
Roller-compacted concrete (RCC)dams represent a departure from conventional mass concrete (CMC) dams due to differences in construction methods and concrete compositions. The analysis of RCC gravity dam safety is affected by the presence of dynamic seismic activity. The CADAM software was used to examine the seismic and stability characteristics of a Gibe-III Zoned RCC gravity dam. The Gibe-III Zoned RCC gravity dam is segmented into four zones, namely the bottom layer, medium lower, medium upper, and upper layer, with each zone having a different concrete grade. The RCC dam undergoes pseudo-static and pseudo-dynamic analysis, which involves evaluating its response to horizontal and vertical accelerations caused by the Operating Base Earthquake (OBE), Maximum Design Earthquake (MDE), and Maximum Credible Earthquake (MCE) loading conditions. The Gibe-III RCC gravity dam is structurally secure when subjected to pseudo-static stress conditions and satisfies the safety requirements for sliding and overturning as specified by the OBE, MDE, and MCE safety factors. According to the pseudo-dynamic study, the dam is deemed secure against the effects of an OBE (Operating Basis Earthquake). The uppermost layer of the dam gets damaged by MDE accelerations. The accelerations of MCE’s impact the higher and mid-upper layers. The dam must be safeguarded in order to counteract MDE. Retrofit strategies must be employed to ensure that dam can withstand the maximum credible earthquake’s peak accelerations.
Study on the Molarity Effect of Sodium Hydroxide on Geopolymer Concrete incorporating Nanosilica
Authors: Amarender Ravula , Rayana Harika 
Published: August 2024

Abstract
Geopolymer concrete, an environmentally friendly alternative to typical Portland cement-based concrete, has been gaining popularity due to its less carbon footprint and increased durability. This study investigates the molarity impact of sodium hydroxide (NaOH) on the characteristics of geopolymer concrete, with the inclusion of Nano Silica as a pozzolanic material. The mechanical and flexural properties of Geopolymer concrete (GPC) incorporating Nano Silica at NaOH (sodium hydroxide) molarities of 2M, 4M, 6M, 8M and 10M under ambient curing are evaluated. Flyash, GGBS-ground granulated blast furnace slag, and Silicon Dioxide (Nano Silica) are utilized as binders in the specially blended Geopolymer concrete mix, which is activated by an alkaline solution. The inclusion of Nano-Silica at about 3% of the weight of the binder ingredient is kept constant during our investigation. Nano Silica mostly works as a filler ingredient in concrete. The mechanical properties, fracture energy (GF), and stress intensity ratio or factor (KIC) of geopolymer concrete specimens of notched unreinforced beams (GPCUB) are among the metrics investigated. All of these findings of Geopolymer specimens are compared to those of Ordinary Portland Cement Concrete (PCC) specimens. The primary objective is to determine the impact of different NaOH molarities and Nano Silica inclusion on the ability of geopolymer-based concrete to withstand cracking and modify its behaviour. As the concentration of NaOH in GPC samples increases, so their mechanical characteristics increases. Silica dissolution has the greatest impact in samples treated with a 10M NaOH solution when compared to other molarities and PCC. This implies that incorporating Nano Silica at varied molarities can effectively improve Geopolymer behaviour by increasing its ability to tolerate brittle failure and fracture propagation. The findings of this study have the potential to give useful insights into the most suitable combination of sodium hydroxide molarity and Nano silica concentration for improved geopolymer concrete characteristics. Understanding these interactions becomes essential for the widespread use of geopolymer concrete for construction applications, which contributes to more sustainable and ecologically friendly practices.
Assessment of strength and dynamic elastic modulus of roller compacted concrete with Metakaolin as supplementary cementitious material through ultrasonic pulse velocity method
Authors: Samanasa Krishna Rao , Varun Teja S , Byagari Jethin 
Published: August 2024

Abstract
Experimental studies on roller compacted concrete (RCC) paving mixes using ultrasonic pulse velocity (UPV) technique were presented in this paper. Mix was proportioned using soil compaction principles and Metakaolin (MK) was used as partial replacement of cement in the ranges of 5% to 30%. Compressive, tensile, flexural strengths, UPV and dynamic elastic modulus values were determined at curing period 24 hours to 90 days. The UPV values of RCC control mix at 1 day are lower for all combination of mixes. But, the UPV values are considerably increased after 3,7, 14,28 and 90 days of curing. Empirical relationships were proposed between UPV, strength and Dynamic Elastic properties of concrete. A new regression equation was proposed to evaluate dynamic elastic modulus of RCC in terms of curing age and proportion of cement replacement with Metakaolin. The equation was (E

d
)t = 97.16(𝑡)0.05 + 0.05(Mk) − 62.
A comparative analysis of pozzolanic material and admixture treatment for black cotton soil as a sub-grade layer
Authors: Poornachandra Rao N S , Manikanta A S , Bindu G H 
Published: August 2024

Abstract
The building material industry, subgrade condition variations, and shifting vehicle patterns all need adjustments in the road construction technology sector. One of the most challenging sub-grade conditions that accounts for a significant percentage of pavement failures is the existence of expanding sub-grade. Black cotton soil covers around 20% of the geographical area in our nation. The soil is not suited for use as an embankment or foundation material because of its undesirable engineering properties, which include substantial swelling and shrinking. The prevalence of these soils in several countries, including India, is such that it is nearly impossible to reroute highways to avoid encountering them. Therefore, in order to enhance pavement performance and save maintenance costs, stabilizing the expansive soil is crucial. The research explores the cost-effectiveness and performance enhancements achieved through the use of industrial waste products, shedding light on their potential for improving sub-grade stability and sustainability in civil engineering projects. This study presents an economic comparative analysis of composite sub-grade layers utilizing black cotton soil, focusing on the influence of incorporating pozzolanic materials and admixtures.
Geotechnical Characterization of Municipal Solid Waste in Raipur City, Chhattisgarh
Authors: Hari Naga Prasad CH. , Chouksey S K 
Published: August 2024

Abstract
Municipal solid waste (MSW) is challenging to dispose of on land due to its varied composition, complicating landfill management and upkeep. The variety of waste materials leads to complexity, which poses significant problems for landfill design. Waste in landfills is more diverse, making management and treatment more challenging. Due to their impact on settlement rates and potential risks of slope instability, aspects such as compaction methods, liner system integrity, and waste composition play a critical role in controlling landfill stability. The physical characteristics and strength parameters of MSW are necessary to determine the stability of the landfill. The Geotechnical characteristics of MSW are crucial for the design of the landfill. MSW was disposed at the Raipur landfill, which has been operating for about 6 years, the sample at 1m depth is taken under the present study. It observed that 30% of MSW was found to be a soil-like material after segregation. The geotechnical properties are determined with soil-like material, which is classified as well-graded sand (SW) as per IS classification. The geotechnical properties such as moisture content, grain size distribution, unit weight, specific Gravity, compaction, cohesion, friction angle, and permeability are determined. It is observed that the geotechnical properties also match the properties of sand. An attempt is made to check out that the soil-like material retained can be used as a fill material as the properties are similar to sand. Comparative analysis of existing landfill MSW geotechnical properties is also done to get a clear and strong idea about the geotechnical properties. Numerical analysis is conducted with the obtained geotechnical properties, shape and size parameters are assumed as per the previous literature. It is observed that the factor of safety obtained from the numerical analysis (SLOPE/W) satisfies the requirements and the design criteria of being safe for solid waste disposal and its operation.
Design of shallow foundation on clayey strata using Ground improvement techniques – A Numerical Study
Authors: Thirmanpalli Sagar , Kommu Suresh , Kadali Srinivas 
Published: August 2024

Abstract
In the construction of engineering structures, deep foundations, such as piles or wells, are commonly employed in continuous clayey soils at considerable depths. However, their utilization is often hindered by the associated high costs and time requirements. Shallow foundations are generally unsuitable due to substantial consolidation settlements. Ground improvement techniques, crucial in contemporary civil engineering projects, offer viable alternatives. Pre-Fabricated Vertical Drains (PVDs) expedite dewatering, accelerating the consolidation process in clayey soils. Additionally, stone columns enhance soil strength and expedite consolidation. This study explores the feasibility of shallow foundations like Isolated/Raft/box foundations employing ground improvement techniques such as PVDs and stone columns in clayey soils. Various properties of clayey soil, coupled with the impact on soil and Safe Bearing Capacity (SBC) at diverse depths utilizing PVDs and stone columns with distinct lengths and diameters, constitute the analytical focus. Numerical methods, specifically employing PLAXIS Software, facilitate a comprehensive examination. Results indicate that, for the prescribed settlement criteria, the Safe Bearing Capacity experienced a notable increase. This underscores the effectiveness of employing PVDs and stone columns as ground improvement techniques for enhancing the stability and performance of shallow foundations in clayey soils.
Mechanical and durability performance of self-compacting geopolymer concrete- A review
Authors: Praseeda D. , Joshita K. , Karthik M. , Mahesh Babu A. , Gurunath Y. 
Published: August 2024

Abstract
Cement production is among the reasons for the emission of CO2 due to the decomposition of the limestone and combustion of coal. Cement plants account for about 8 % of the CO2 emissions into the atmosphere worldwide. There is a great need to look for opportunities to replace cement. Geopolymer concrete is one such special concrete wherein the cement is not utilized. By-products of the industries for example GGBS, Silica fume, and fly ash were used as precursors along with the alkaline activators, NaOH and Na2SiO3, to build up the binding nature like that of conventional concrete. Geopolymer self-compacting concrete is also a type of high-performance concrete where external compaction is not needed. Overheads costs such as cost towards machinery, fuel, and labour can be avoided. This work summarises the key points of the self-compacting geopolymer concrete developed by the researchers incorporating by-products of the industries along with the mechanical and durability performance. This paper examines the impact of parameters critically such as binding materials, molarity, and curing regimes on the mechanical and durability performance of self-compacting geopolymer concrete. It can be inferred from the literature survey conducted that the substitution of SCGC for traditional concrete avoids the disposal problem of waste utilization and serves to be environmentally friendly without compromising on durability and mechanical performance.
Validation of an electronic transformer electromagnetic nuisance online monitoring system in a true type platform
Authors: He Yumin , Zhu Jianyang , Zhang Houyi , Wang Yu , Dai Qiji 
Published: August 2024

Abstract
With the construction of power grid intelligence and digital power grid, an electronic transformer is one of the key equipment, and its performance stability and reliability are crucial to the safe and stable operation of the power system. Due to the poor operational reliability of electronic transformers, the difficulty of operation and maintenance, and the limited performance testing methods, it is necessary to monitor the operational status of electronic transformers, and the traditional monitoring methods have been unable to meet the needs of the development. In this paper, we designed an online monitoring system for electronic transformers using voltage and electric field sensors and a high-speed high-capacity data acquisition system and verified its online monitoring function through actual testing under the true-type test platform.