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To assess the protective effect and adsorption behaviour of Azadirachta indica extract in controlling mild steel corrosion in 1 M H₂SO₄ and 2 M HCl.

The inhibitive effect of the plant extract was monitored using the gas‐volumetric technique. The inhibition mechanism was inferred by curve fitting of the experimental data to known adsorption isotherms and the trend of inhibition efficiency with temperature.

Azadirachta indica extract effectively inhibited steel corrosion in the acid media studied by virtue of adsorption. The inhibitor adsorption characteristics were approximated by Langmuir isotherm. The extract functioned as a mixed inhibitor, depending on its concentration. The prime effect at lower concentration was mitigation of the cathodic reaction by physical adsorption of protonated species in the extract and at higher concentration the anodic reaction was inhibited by chemisorption of molecular species.

This paper provides novel information on the effectiveness of Azadirachta indica extract as a green corrosion inhibitor for steel in highly acidic environments as well as possible mechanisms of the inhibitive action.

The purpose of this study is to evaluate the content of bioactive pigments in coloured callus of Azadirachta indica and to understand the correlation between the callus colours with their bioactive constituents, antioxidant properties and cytotoxicity. These assessments will yield valuable insight into the use of in vitro-derived pigments for possible use as functional natural colourants.

In this study, the authors have successfully developed a protocol to produce leaf-derived callus of various colours with enhanced content of bioactive pigments in A. indica through plant tissue culture. Comparative analysis of the pigments content (chlorophyll, carotenoid, phenolics and anthocyanins) in the coloured callus was conducted, followed by evaluation of its bioactive properties. The antioxidant properties against 2,2-diphenyl-1-picrylhydrazyl and 2,2′-azinobis(3-ethylbenzothiazoline-6-sulfonic acid) radicals, ferric reducing antioxidant power and cytotox activities of the coloured callus extracts were also reported.

Callus of various colours were successfully produced in A. indica through plant tissue culture, and their valuable pigment content and bioactivity were evaluated. The green callus contained the highest amount of anthocyanin, followed by brown and cream callus. The total anthocyanin contents in both the green and brown callus was more than two-fold higher than that in cream callus. Contrasting observation was obtained for total phenolic content (TPC), where the TPC of cream callus was significantly higher than that in brown callus. Nevertheless, the green callus also exhibited the highest TPC. Green callus also contained the highest amount of total chlorophyll and carotenoid, as well as exhibited the highest antioxidant potential, and was found to be the only extract with active cytotox activity against SKOV-3 cells. Correlation analysis revealed that the excellent bioactivity exhibited by the coloured extracts was strongly correlated with the bioactive pigments present in the callus.

The major bioactive compounds identified in the methanolic extracts of A. indica coloured callus are anthocyanins, phenolics, chlorophylls and carotenoids. Future research work should include improvements in the extraction and identification methods, which may lead to detection and determination of other compounds that could attribute to its bioactivity, to complement the findings of the current study.

This analysis provides valuable information on the application of plant tissue culture as an alternative source for sustainable production of major pigments with medicinal benefits in A. indica for possible use as functional natural colourants.

A comparative study on bioactive pigment production in coloured callus from A. indica leaves and its antioxidant potential and cytotoxicity is original. To the best of the authors’ knowledge, this is the first report detailing a comparative evaluation on the production of coloured callus in A. indica and its relative biochemical composition and bioactive properties.

The textile sector is moving towards new technologies, where the application of nanotechnology is offering fabrics with multifunctional properties making fabric odourless, hydrophobic, durable and self-cleaning. This aim of this research is to investigate self-cleaning ability of denim fabric with the application of zinc oxide nanoparticles (ZnO NPs) synthesized naturally. The primary focus of this investigation is achieving sustainability mark through green synthesis of ZnO NPs.

In this analysis, ZnO NPs being one of the metal oxides exhibiting self-cleaning, UV-protective and anti-microbial properties were synthesized naturally using Azadirachta Indica leaves. The prepared NPs were characterized by using X-ray diffraction and scanning electron microscopy analyses confirming their size and crystalline structure. Different formulations were investigated with varying concentration of zinc oxide and auxiliaries onto the denim fabric using pad-dry-cure application technique.

XRD analysis confirmed the successful green synthesis of ZnO NPs. SEM analysis revealed the homogeneous and hexagonal wurtzite NPs deposition on the denim fabric. It was ascertained that with 5% ZnO NPs and 7% Binder concentrations, the formulation resulted in a smooth and even layer on the denim fabric maintaining the appearance and feel at the same time offers appreciable grading (Grade 4) against the stringent stains of Ketchup, Coffee, Grape and Orange Juice with insignificant change in tensile strength.

In this study, self-cleaning attributes of denim fabric with zinc oxide nano formulations of different composition was studied to achieve promising functional properties in a single step not studied earlier.

The COVID-19 pandemic has popularized wearing face masks for personal protection. However, the protection afforded by a mask is decreased if an individual accidently touches the outer surface of the mask and then touches other parts of their face. To overcome this problem, antimicrobial masks have become commercially available. However, many are disposable and/or made from synthetic antimicrobial agents which have a negative impact on the environment. The purpose of this study was to create material for stitching antimicrobial masks that are reusable and natural.

The authors developed natural antimicrobial finishes from Azadirachata indica, Butea monosperma and Litchi chinensis leaves. The authors used biodegradable polyurethane binder and pad-dry-cure method to apply them on 100% cotton fabric. The authors used Fourier-transform Infrared Spectroscopy (FTIR) and Scanning Electron Microscope (SEM) to confirm the application and ASTM E2149 to assess the efficacy and wash-resistance of the finish.

Fabric treated with leaves of A. indica, B. monosperma and L. chinensis showed 80%, 100 and 100% antimicrobial activity, respectively. All fabrics were washed 25 times in home laundry cycles and maintained 100% of their antimicrobial effect.

These findings highlight that B. monosperma and L. chinensis finishes on cotton fabric can be a used as a material for stitching antimicrobial, natural and reusable masks that provide more protection than traditional masks but do not pose the environmental concerns of disposable masks or synthetic finishes. This study can be furthered by performing more laundry cycles to determine if the finishes remain 100% effective beyond 25 cycles.

The purpose of this paper is to assess the sustainability of a forestry management strategy in checkmating desert encroachment and it also examines the impacts of the Forestry II program on agricultural productivity in the rural communities.

The study adopted a quantitative approach in assessing the rural farmers’ level of participation in the Forestry II program in which 201 respondents were interviewed in the study area. Structured questionnaires’ were also administered to afforestation officials/extension workers in the two states regarding the different components of the projects and probable cause(s) of failures/successes as well as the level of involvement of the community in the project. Field observations of the project sites were also carried out with a view to examining the level of achievements on the physical components of the projects.

The findings of this study revealed that, involvement of the stakeholders and participation of the community was lacking at the early stage of the program and the negligence of indigenous knowledge as well as the influence of bottom up approach was not incorporated in the project. The study further revealed that, appreciable positive impacts have been recorded at various levels of its implementation. The improvement of livelihood of the rural people through increased forest products supply was noted, fuel-wood and poles supply were also increased and this had gone a long way in creating employment for the rural dwellers.

The study involved the establishment of shelterbelts, windbreaks, woodlots, orchards and nurseries which were complimented by social forestry, and which raised public awareness through campaigns such as school forestry programs, forestry extension services and a fuel-wood conservation program.

The study articulated success and failure as well as a detailed assessment of the Forestry II project. The study showed that government could significantly combat desertification in the arid zones through sustainable afforestation if adequate resources were employed.

This study/paper aims to evaluate the floral richness of the central part of Chattogram city, Bangladesh. Chattogram is recognized as the largest port city and the commercial capital of Bangladesh, which confronts faster urbanization and swift infrastructure development. Green spaces in and around Chattogram city are shrinking sharply, which resulted in rapid loss of floral and faunal resources in this area. The present study was carried out from February 2018 to January 2019 to enumerate the vascular plant species of the Sulakbahar ward located in the central part of Chattogram City, Bangladesh.

The study area was categorized into 10 habitats to assess the variation of floral composition. The extensive whole area survey method was applied to record the flora from all sorts of plant habitats of the research area.

The study enumerated 418 vascular plant species under 315 genera and 120 families including natural, planted and cultivated from the study area. The habit form of the recorded plant composition indicated that herbs (35%) constitute the major plant category followed by trees (34%), shrubs (17%), climbers (12%), ferns (1%) and orchids (1%). The study also indicated that exotic species (50.3%) became dominant than native species (49.7%) in Chattogram city because of their scenic beauty, easy propagation and ornamental value to the city planners and inhabitants.

It appeared that floral resources of the Chattogram city area are in great threat due to aggressive and unplanned infrastructure development for housing, offices and institutions by replacing the green spaces. The study recommended that urgent protection measures should be taken to conserve and protect the existing floral resources for the well-being of the urban people.

This study aims to study electrochemically and by weight-loss experiments the effect of UAE Rhazya Stricta Decne extract on the corrosion inhibition of mild steel in 1.0 M HCl solution, which will serve researchers in the field of corrosion.

Weight loss measurements were carried out on mild steel specimens in 1.0 M HCl and in 1.0 M HCl containing various concentrations (ranging from 2.0 to 0.002 g/L.) of the UAE Rhazya Stricta Decne extract at temperatures ranging from 303 to 343 K.

The aqueous Rhazya Stricta Decne leaves extract was found to be a highly efficient inhibitor for mild steel in 1.0 M HCl solution, reaching about 90 per cent at 2.0 g/L and 303 K, a concentration considered to be very moderate. Even with one-tenth of that concentration, 0.2 g/L, an inhibition of about 82 per cent was obtained at 303 K. The rate of corrosion of the mild steel in 1.0 M HCl is a function of the concentration of the Rhazya Stricta Decne extract. This rate increases as the concentration of the Rhazya Stricta Decne extract is increased. The percentage of inhibition in the presence of this inhibitor was decreased with temperature which indicates that physical adsorption was the predominant inhibition mechanism because the quantity of adsorbed inhibitor decreases with increasing temperature.

This inhibitor could have application in industries, where HCl solutions at elevated temperatures are used to remove scale and salts from steel surfaces, such as acid cleaning of tankage and pipeline, and may render dismantling unnecessary.

This paper is intended to be added to the family of green corrosion inhibitors which are highly efficient and can be used in the area of corrosion prevention and control.

Plant development and use as green corrosion inhibitors are already recognized as one of the most environmentally friendly and effective protocols. In recent years, efforts have been made to find green corrosion inhibitors as an alternative to synthetic inhibitors for metals in acid medium. This paper aims to report the investigation of use of aqueous extracts of Tamarindus Indica as green inhibitors for corrosion of metals within different circumstances.

The use of Tamarindus Indica extracts (leaves, stem, fruit pulp and fruit husk) as corrosion inhibitors for mild steel and aluminum in different mediums (HCl, H2SO4, formic acid and citric acid) at different temperatures was investigated.

The inhibitory efficiency of Tamarindus Indica extracts increases with increasing concentration and decreases with increasing temperature. Langmuir is the adsorption isotherm, and the extract (inhibitor) is a mixed-type inhibitor (physisorption and chemisorption).

Tamarindus extracts (leaves, stem, fruit pulp and fruit husk) are effective inhibitors and can be used to protect metals from corrosion at different circumstances.

To the best of the authors’ knowledge, this is the first review that discusses the use of Tamarindus Indica extracts as corrosion inhibitors for metals.

The textile industry is evolving toward nanotechnology, which provides materials with self-cleaning properties. This paper aims to provide a thorough explanation of the green synthesis and mechanism of ZnO nanoparticles, with prospective applications of zinc oxide nanoparticles (ZnO NPs) in self-cleaning textiles.

This review introduces a green mechanism for the synthesis of ZnO NPs using plant extracts, their self-cleaning properties and the mechanisms of physical, chemical and biological self-cleaning actions for textile applications.

ZnO NPs are among the several nanoparticles that are beneficial for self-cleaning textiles because of their exceptional physical and chemical properties, although review publications addressing the use of ZnO NPs in textiles for self-cleaning are uncommon. These results indicate that the plant-synthesized ZnO NPs display excellent biological, physical and chemical self-cleaning properties, the mechanism of which involves photocatalysis, surface roughness and interactions between ZnO NPs and bacterial surfaces.

Nanoformulations of plant-synthesized ZnO have been reviewed to achieve promising self-cleaning textile properties and have not been reviewed earlier.