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Clitoria ternatea is anelegant perennial climber with blue or white flowers widely distributed in and around tropical Asia. The plant is regarded as "butterfly pea" and "shankhapuspi". It is traditionally used in Ayurveda to treat neurological disorders, sterility in females, inflamed eyes and swollen joints. The present study evaluates the phytochemicals in the plant extracts by qualitative and quantitative biochemical methods. The antimicrobial and antioxidant properties were also analyzed. Further, the Phyto-chemical constituents were studied by GC-MS analysis. Hexacosane and Hexatriacotane were the major constituents found. This paper focuses on the medical constituents of the C.ternatea flower extracts. [ABSTRACT FROM AUTHOR]

In this study, fusiform bismuth (Bi) was synthesized, and its photocatalytic performance, degradation mechanism, and pathways for removing rhodamine B (RhB) at different pH levels were investigated. Additionally, the morphologies, structural characteristics, surface electronic states, optical properties, active species, and potential degradation pathways of RhB over the fusiform Bi were analyzed. The comparison of the results before and after RhB degradation using the fusiform Bi revealed the formation of a Bi/BiOCl heterojunction photocatalyst. At pH 2.0, 3.0, 5.0, 7.0, and 9.0, the heterojunction exhibited excellent photocatalytic activity, with RhB removal efficiencies of ~97%, 96.7%, 72.6%, 53.5%, and 27.6%, respectively. Moreover, total organic carbon and chemical oxygen demand analyses were performed to evaluate the mineralization rates of RhB with the fusiform Bi at pH 3.0 and 7.0. Furthermore, the effects of catalyst content, initial RhB concentration, light source distance, inorganic anions, and reactant temperature on the photocatalytic performance of the fusiform Bi were investigated. Additionally, the types of active species and potential photocatalytic mechanisms for RhB degradation over the fusiform Bi at different pH levels (3.0 and 7.0) were elucidated. The appropriate degradation pathways were identified via liquid chromatography–mass spectrometry at pH 3.0 and 7.0. [ABSTRACT FROM AUTHOR]

The early strength of geopolymers (GPs) and their composites is higher, and the hardening speed is faster than that of ordinary cementitious materials. Due to their wide source of raw materials, low energy consumption in the production process, and lower emissions of pollutants, they are considered to have the most potential to replace ordinary Portland cement. However, similar to other inorganic materials, the GPs themselves have weak flexural and tensile strength and are sensitive to micro-cracks. Improving the toughness of GP materials can be achieved by adding an appropriate amount of fiber materials into the matrix. The use of discrete staple fibers shows great potential in improving the toughness of GPs. Sisal is a natural fiber that is reproducible and easy to obtain. Due to its good mechanical properties, low cost, and low carbon energy usage, sisal fiber (SF) is a GP composite reinforcement with potential development. In this paper, the research progress on the effect of SF on the properties of GP composites in recent decades is reviewed. It mainly includes the chemical composition and physical properties of SFs, the preparation technology of sisal-reinforced geopolymers (SFRGs), the microstructure analysis of the interface of SFs and the GP matrix, and the macroscopic mechanical properties of SFRGs. The properties of SFs make them have good bonding properties with the GP matrix. The addition of SFs can improve the flexural strength and tensile strength of GP composites, and SFRGs have good engineering application prospects. [ABSTRACT FROM AUTHOR]

The 21st century has witnessed a substantial increase in the demand for construction materials, mainly influenced by the growing population. This increase in demand has resulted in higher prices for these materials and has also placed considerable burdens on environmental resources, prompting the search for eco-friendly and economically viable alternatives such as geopolymer materials to replace traditional materials like cement. The benefits of geopolymer materials as substitutes for cement in concrete extend beyond their exceptional durability. Initially, geopolymer was introduced to address the environmental impact arising from carbon dioxide emissions and the substantial consumption of fossil fuels through the production of cement. The current review investigates recent advances regarding the durability characteristics of geopolymer materials. This includes aspects such as water absorption, temperature resistance, sulfuric acid resistance, sulfate resistance, chloride ion penetration, and freeze–thaw resistance, among others. The results of this review highlight geopolymer concrete's enhanced durability over traditional cement-based concrete. Furthermore, this review offers recommendations and outlines potential research avenues for further exploration of geopolymer concrete. [ABSTRACT FROM AUTHOR]

The construction industry is among the most prominent contributors to global resource consumption, waste production, and greenhouse gas emissions. A pivotal step toward mitigating these sectoral impacts lies in the adoption of a circular production and consumption system. The use of alternative waste materials can mitigate landfill accumulation and the associated detrimental environmental effects. To highlight unconventional materials, this study began with a bibliometric assessment via a bibliography analyzis software called "Bibliometrix" (version 4.1.3). The outputs from the analyzis can assist in identifying research trends, gaps in literature and benchmark research performance. The search engine used for sourcing publications was Scopus, using the main criteria as "Waste materials used in building and construction". The time-period analysed was from 2013 to 2023. The results included publications obtained in journal articles, book chapters and conference proceedings. The assessment reviewed 6238 documents from 1482 sources. The results revealed an array of waste materials; however, rubber, textiles, and ceramics had a significant reduction in research attention. Rubber waste presents promising opportunities in civil concrete construction methods. The preparatory steps of textile fibres in composite materials are frequently disregarded, resulting in structural issues for the end-product. Obstacles persist in ceramic technology due to the absence of transparency, primarily because industry entities closely safeguard proprietary information. While sustainability research often emphasizes emissions, practical trials commonly revolve around integrating materials into current systems. A more comprehensive approach, contemplating the complete lifecycle of materials, could provide deeper insights into fostering sustainable construction practices. Researchers can use these findings when determining trends, research gaps, and future research directions. [ABSTRACT FROM AUTHOR]

The Internet of Things (IoT) has recently attracted much interest from researchers due to its diverse IoT applications. However, IoT systems encounter additional security and privacy threats. Developing an efficient IoT system is challenging because of its sophisticated network topology. Effective access control is required to ensure user privacy in the Internet of Things. Traditional access control methods are inappropriate for IoT systems because most conventional access control approaches are designed for centralized systems. This paper proposes a decentralized access control framework based on smart contracts with three parts: initialization, an access control protocol, and an inspection. Smart contracts are used in the proposed framework to store access control policies safely on the blockchain. The framework also penalizes users for attempting unauthorized access to the IoT resources. The smart contract was developed using Remix and deployed on the Ropsten Ethereum testnet. We analyze the performance of the smart contract-based access policies based on the gas consumption of blockchain transactions. Further, we analyze the system's security, usability, scalability, and interoperability performance. [ABSTRACT FROM AUTHOR]

Geopolymers are amorphous, quasi-crystalline, three-dimensional networked gel structures formed by the reaction of aluminosilicate raw materials and alkali activators and are composed of silicon-oxygen tetrahedrons and aluminum-oxygen tetrahedrons. They have excellent mechanical properties, durability and environmental friendliness and can be used as a substitute for Portland cement in civil engineering. In this paper, the current research achievements of geopolymers are reviewed, including the structure type, preparation process, mechanical performance, durability and application of geopolymers in civil engineering. When compared with those of ordinary Portland cement, the mechanical properties of geopolymers not only meet the specification requirements but also show carbonation resistance, acid resistance and high temperature resistance. In addition, the raw materials of geopolymers, such as fly ash and blast furnace slag, are all derived from industrial waste; the use of geopolymers can realize waste recycling, which has extremely high economic benefits. This paper introduces its applications in soil stabilization and silt solidification, curing heavy metals, pavement repair materials and so on. The shortcomings in the current research of geopolymer are also briefly analyzed. This article reviews geopolymers from multiple perspectives, trying to give a more comprehensive understanding of geopolymers. [ABSTRACT FROM AUTHOR]

Geopolymer (GP) is environmentally friendly, has good mechanical properties and long-term workability, and has broad application prospects. However, due to the poor tensile strength and toughness of GPs, they are sensitive to microcracks, which limits their application in engineering. Fiber can be added to GPs to limit the growth of cracks and enhance the toughness of the GP. Plant fiber (PF) is cheap, easy to obtain, and abundant in source, which can be added to GP to improve the properties of composites. This paper reviews recent studies on the early properties of plant fiber-reinforced geopolymers (PFRGs). In this manuscript, the properties of PFs commonly used for GP reinforcements are summarized. The early properties of PFRGs were reviewed, including the rheological properties of fresh GPs, the early strength of PFRGs, and the early shrinkage and deformation properties of PFRGs. At the same time, the action mechanism and influencing factors of PFRGs are also introduced. Based on the comprehensive analysis of the early properties of PFRGs, the adverse effects of PFs on the early properties of GPs and the solutions were summarized. [ABSTRACT FROM AUTHOR]

Both geopolymer and plant fiber (PF) meet the requirements of sustainable development. Geopolymers have the advantages of simple preparation process, conservation and environmental protection, high early strength, wide source of raw materials, and low cost. They have broad application prospects and are considered as the most potential cementitious materials to replace cement. However, due to the ceramic-like shape and brittleness of geopolymers, their flexural strength and tensile strength are poor, and they are sensitive to microcracks. In order to solve the brittleness problem of geopolymers, the toughness of composites can be improved by adding fibers. Adding fibers to geopolymers can limit the growth of cracks and enhance the ductility, toughness and tensile strength of geopolymers. PF is a good natural polymer material, with the advantages of low density, high aspect ratio. It is not only cheap, easy to obtain, abundant sources, but also can be repeatedly processed and biodegradable. PF has high strength and low hardness, which can improve the toughness of composites. Nowadays, the research and engineering application of plant fiber-reinforced geopolymers (PFRGs) are more and more extensive. In this paper, the recent studies on mechanical properties of PFRGs were reviewed. The characteristics of plant fibers and the composition, structure and properties of geopolymers were reviewed. The compatibility of geopolymer material and plant fiber and the degradation of fiber in the substrate were analyzed. From the perspective of the effect of plant fibers on the compression, tensile and bending properties of geopolymer, the reinforcing mechanism of plant fibers on geopolymer was analyzed. Meanwhile, the effect of PF pretreatment on the mechanical properties of the PFRGs was analyzed. Through the comprehensive analysis of PFFRGs, the limitations and recommendations of PFFRG are put forward. [ABSTRACT FROM AUTHOR]

The cement production consumes many natural resources and energy, pollutes the environment, and cannot meet the current building materials' green and sustainable development requirements. Therefore, geopolymers have gained popularity as cement replacements in recent years. Geopolymers have promising characteristics such as low energy consumption and carbon footprint, valuable compressive strength, fire resistance, flame resistance and good durability. However, these materials suffer from low tensile and flexural strength. Hence, fibres are added to overcome these issues and enhance their toughness index. Natural fibres are biodegradable, low-cost, renewable materials and widely available in many countries. This article reviewed previous Natural Fibre Reinforced Geopolymer Composites (NFRGC) studies, focusing on compressive strength, tensile and flexural strengths, and toughness. In addition, the available literature on the effect of the treatment methods of natural fibres on the mechanical properties of NFRGC has been addressed. The findings indicate that adding the appropriate type and content of natural fibres to geopolymer composites can enhance their mechanical properties. However, more attention should be paid to the effects of the pre-treatment of natural fibres on the performance of NFRGC. [ABSTRACT FROM AUTHOR]

This study explores the utilization of polyethylene bags and PET bottles as a fiber in the production of lightweight non-autoclaved plastic fiber-reinforced aerated concrete (NAPFRAC), which has the potential to replace conventional bricks. The study begins by examining global plastic pollutant production and their characterization and the need for a forecast of plastic pollution worldwide. Optimization using Design-Expert 9.0 is used to estimate the optimum mix of NAPFRAC. The mechanical properties of the optimum mix are determined, and a scaled-down model of wall panels is cast to study their behavior and vertical and horizontal ultimate load-carrying capacity. The results are compared to those of conventional first-class burnt clay bricks, and it is found that NAPFRAC wall panels show a 28% increase in vertical load-carrying capacity and 40% in horizontal load-carrying capacity. An analytical study of a high-rise building with NAPFRAC as infill panels is carried out to check the reduction of steel reinforcement in structural sections. Microstructural analysis using SEM (scanning electron microscopy) and XRD (X-ray diffraction) is conducted to identify the morphology and mineralogical composition of the NAPFRAC. Energy studies are also carried out on the mix ratio to identify the embodied carbon dioxide and energy required. Overall, this study highlights the potential of NAPFRAC as a lightweight alternative to conventional bricks. The use of plastic waste as a fiber in concrete production could have a positive impact on the environment by reducing plastic pollution. The results of this study could also have practical applications in the construction industry, especially in the design of high-rise buildings., (© 2023. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

The purpose of this study is to explore the best preparation process of asphalt self‐healing microcapsules. Response surface design and single factor design were used to optimize the preparation process parameters of asphalt self‐healing microcapsules, and the prediction model of core content was established. The optimal preparation process was determined. The results of response surface design showed that the interaction among emulsifier concentration/reaction temperature, core‐shell ratio/reaction temperature, and pH/reaction temperature had significant effect on the core content of microcapsules; the microcapsules prepared by the optimal process were spherical with an average particle size of 90.19 μm. The results of thermogravimetric analysis (TGA) and heating simulation test showed that the microcapsule can delay the damage of the core in high temperature environment; the results of nanoindentation test showed that the young's modulus and hardness of the microcapsules were about 2.50 and 0.28 GPa, respectively. Finally, the improvement mechanism of self‐healing performance of asphalt by microcapsules was revealed by fluorescence microscope. [ABSTRACT FROM AUTHOR]

Summary: Wireless Sensor Network (WSNs) is a collection of sensor nodes with a base station for data transmission. Mostly the network has various paths with the unbalanced nodes; therefore, energy consumption is always high. This causes the letdown of quality of service (QoS) routing metrics such as delay, inefficient throughput in WSNs. This paper concentrates on this problem and proposes an energy‐efficient multipath routing (EEMR) protocol for WSNs. EEMR protocol computes the optimal path using the multi‐objective lion optimization algorithm with less energy consumption. The main aim of EEMR protocol is to achieve an efficient path among multiple paths to satisfy quality requirements such as delay, throughput, energy consumption, delivery ratio, loss ratio, and latency. Thus, the proposed EEMR protocol is designed with a multi‐objective function using an optimization algorithm and implemented in MATLAB. The simulation results show that the performance of the proposed protocol is very efficient in comparison to state of the art. [ABSTRACT FROM AUTHOR]

Introduction: Physical Activity (PA) is an important component of a healthy pregnancy, for both the mother and her child. Sedentary lifestyle during pregnancy may increase development of pregnancy related musculoskeletal discomforts. Studies show that 25% of women experience severe Pelvic Girdle Pain (PGP) during pregnancy and 8% are severely disabled due to PGP. Aim: To analyse the association between the PA and PGP during pregnancy. Materials and Methods: This cross-sectional study was conducted at antenatal outpatient department, Sri Ramachandra Hospital, Chennai, Tamil Nadu, India from November 2019 to March 2020. Total 250 mothers were screened and finally 150 participants were selected. They were asked to fill-up the Pregnancy Physical Activity Questionnaire (PPAQ), Pregnancy Musculoskeletal Dysfunction Scale (PMDS) to assess the PA level and musculoskeletal dysfunction. Mothers who complaints of PGP were clinically diagnosed and were asked to fill the Pelvic Girdle Questionnaire (PGQ). Data was analysed using Statistical Package for the Social Sciences (SPSS) version 20.0. Results: A total of 26 (17.33%) pregnant women in this study had PGP. The association between the total PA and PGP showed that the risk of PGP decreased as the PA increased which was statistically significant (p=0.03). PGP was also significantly associated with increased body weight (p=0.014). Conclusion: It was found that there was an association between total PA and PGP in pregnancy. Increased PA is associated with reduction in PGP. Hence, moderate PA is recommended during pregnancy. [ABSTRACT FROM AUTHOR]

The paper gives a comparative analysis between different coordination structures, determined by single crystal XRD, of Zn and Cd NTP complexes used as corrosion inhibitors for steels in aqueous media according to voltammetry data. The paper provides the results for polymeric O‐coordinated complexes and mononuclear N,O‐coordinated complexes of both metals. Structural differences between complexes of the same metal which possess different structures (polymeric and mononuclear) lead to their different anti‐corrosion activity. Polymeric O‐coordinated complexes of both metals exhibit low anti‐corrosion activity. N,O‐coordinated complexes of Zn and Cd are effective corrosion inhibitors, with Cd complex being four times more effective than Zn complexes. [ABSTRACT FROM AUTHOR]

Here, calcium tungstate nanoparticles (CWONPs) were synthesized by the hydrothermal method. The reaction parameters including calcium salt concentration, surfactant concentration, reaction time and temperature have been optimized by Taguchi Design Method for smaller particles size. The morphology, size, crystallinity and chemical structure of nanoparticles were investigated by different methods. The optimized calcium tungstate nanoparticles (opt-CWONPs) with average size of 51 nm were showed outstanding removal effectiveness for three different pollutants including methyl orange, imipenem and imatinib mesylate over UV illumination. Nearly, 100% of methyl orange, 98% of imipenem and 60% of imatinib mesylate are degraded at 1800s over opt-CWONPs with banggap 3.7 eV. In addition, a modified carbon paste electrode was formed with opt-CWONPs and linear sweep voltammetry was used to analyze its electrocatalytical activity in acidic media. The findings showed that the carbon paste electrode modified by opt-CWONPs had a higher current density in the hydrogen evolution reaction (HER) than the bare carbon paste electrode. This article has subsequently revealed a revolutionary method for opt-CWONPs preparation and demonstrated its multifunctionality as photocatalyst and electrocatalyst active ingredients. [ABSTRACT FROM AUTHOR]

Herein, we reported the imino phosphonate compounds: (4‐methoxy‐benzylidene‐amino‐phenyl‐methyl‐phosphonic acid diethyl ester (MBPDE), 4‐hydroxy‐benzylidene‐amino‐phenyl‐methyl‐phosphonic acid diethyl ester (HBPDE) and 4‐hydroxy‐3‐methoxy‐benzylidene‐amino‐phenyl‐methyl‐phosphonic acid diethyl ester (HMBPD) form the chemical reaction of diethyl (α‐amino benzyl)phosphonate hydrochloride and substituted benzaldehyde. These compounds were characterized by various spectroscopic techniques: FT‐IR, Mass, UV–VIS, 1H NMR and 13 C NMR. Additionally, the optimized molecular structures, FT‐IR, natural bond orbitals (NBOs), frontier molecular orbitals (FMOs), non‐linear optical (NLO) properties were calculated by the density functional theory (DFT) using the B3LYP functional with the 6–311+G(d,p) basis set. Moreover, UV–Visible spectrum of MBPDE, HBPDE and HMBPD were predicted in different solvents using the time dependent TD‐DFT [B3LYP/6‐311+G(d,p)] method using Polarizable Continuum Model (PCM). The non‐linear optical (NLO) properties were calculated by M06 functional with the 6–311+G(d,p) basis set. A synergistic relationship is observed between the experimental and theoretical findings. NBO analysis provided insights about the stability and charge delocalization of the entitled molecules. The global reactivity descriptors were achieved through HOMO‐LUMO energies. The efficiency of the entitled molecules concerning charge transfer and participation in diverse chemical reactivities were figured out perceptibly by applying the frontier molecular orbitals (FMOs) analysis. The average polarizability <α> values: 277.184, 261.332 and 280.254 a.u. of the MBPDE, HBPDE and HMBPD were determined respectively. The total first hyperpolarizability (βtot) values of the MBPDE, HBPDE and HMBPD were also obtained to be 992.900, 781.527 and 1107.526 a.u. respectively. The compound HMBPD comprising of higher magnitude of average polarizability and the total first hyperpolarizability (βtot) values than MBPDE and HBPDE molecules. Moreover, NLO properties of urea molecule were found smaller in comparison to the MBPDE, HBPDE and HMBPD. The medicinal importances of these novel compounds as well as its contribution towards nonlinear optical field are our future targets. [ABSTRACT FROM AUTHOR]

Background: Physical activity is very important during pregnancy for better maternal and foetal health. The physical activity during pregnancy varies with different periods of gestation. Therefore, the pregnancy physical activity is quite difficult to assess. The pregnancy physical activity questionnaire developed by Prof. Lisa Chasan Taber et al. (2004) is one of the few currently available questionnaires for measuring the physical activity during pregnancy. It was found to have few activities like mowing the lawn with mower which were not practiced in Tamil population thus there was a need to translate and culturally adapt the questionnaire. Methodology: Total 75 mothers were screened and finally 50 participants were selected according to the inclusion and exclusion criteria. First session the mothers were administered with Tamil PPAQ and they were asked to fill details about past 7 days. The same was repeated after 1 week with English questionnaire for validation. In the last session, the mothers were administered with Tamil PPAQ for reliability analysis. Results: Internal consistency analysis of the Tamil PPAQ using Cronbach's alpha between the two Tamil PPAQ is good with the value 0.83. The test retest reliability was done between the Tamil PPAQ and English PPAQ by Intraclass correlation coefficient which ranged from good to excellent (0.81–0.95). Conclusion: The Tamil PPAQ is a valid and reliable tool. It has good accuracy for the measurement of physical activity of various intensities and types among pregnant women. [ABSTRACT FROM AUTHOR]

This paper presents the use of self-assembled molecular (SAM) layers of fluorophosphonic acids developed on aluminum surface. The SAM monolayers were adsorbed from ethanol solution, characterized by surface morphology visualized by atomic force microscopy, and by the wettability by contact angle measurements. The anti-corrosion efficiency of the nanolayers was determined by ex situ AFM measurements and by electrochemical techniques, which indicated the importance of the fluorophosphonic acid concentration and of the film formation time in the molecular deposition process. The morphological change with or without nanolayers caused by the corrosive environment was in accordance with the electrochemical results. [ABSTRACT FROM AUTHOR]

Background and aim: Hydroalcoholic (70°) extract of leaves of Myrtus communis has been shown to have antidiabetic effect in streptozotocin induced diabetic rats in our previous study. In this study, we intended to determine the components of the mentioned extract and identify the mechanism for its action. Materials and Methods: The leaves of Myrtus communis were extracted using petroleum ether by soxhlet. 100 g of the powder remaining in the strainer soxhlet apparatus were placed in two different percolators. The extraction was carried out by percolation method with ethanol-water (1-1) or distilled water in 72 hours. The remaining powder of water extract was further extracted using again ethanol (percolation method). The study was conducted on forty-eight matured male Charles-River rats (200-300 g) divided into 6 groups (n=8). Diabetes mellitus was induced by single intraperitoneal injection of 35 mg/kg of streptozotocin (STZ). Hydroalcoholic, water, and ethanol extracts of Myrtus communis were used at the dose of 4, 2, and respectively 2 g/kg body weight per day for 5 days. All extracts were given orally by gastric tube. Results: We found that the total hydroalcoholic extract of Myrtus communis leaves showed a moderate antidiabetic effect. In this study, we showed that the ethanolic extract of leaves (2 g/kg) had a better hypoglycemic effect in diabetic rats compared with the aqueous extract (p < 0.05). Our results also showed that the oral administration of the ethanolic extract (2 g/kg) had an additive effect on the hypoglycemic action of glibenclamide (oral administration 5 mg/kg) in rats. Conclusion: A review of previous researches on leaves of Myrtus communis and also the present study suggests that the extracts may stimulate the β-cells of pancreas to release insulin. [ABSTRACT FROM AUTHOR]

A new zinc aminophosphonate corrosion inhibitor (ZnATMP) containing the Zn-N bond in the coordination environment of zinc has been synthesized, separated and studied. The inhibition coefficient according to the all-Union State Standard 9.502 is 14.7. The interaction of the metal-coordination corrosion inhibitor ZnATMP with the surface of carbon steel has been studied by X-ray photoelectron spectroscopy. The structure of the protective layer, its stability in the temperature range of 300-575 K and the mechanism of thermal destruction have been investigated. It is shown that the interaction of the nitrogen-containing chelate corrosion inhibitor with the steel surface leads to the formation of the surface protective layer, the atoms of which form strong covalent bonds Fe-O-P-Zn-N(C). Fe atoms pass into a high-spin state. Thermal action on the protective film results in its destruction at 575 K. [ABSTRACT FROM AUTHOR]