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Nanoparticles synthesised using natural resources is a cost-effective and ecofriendly technique with a number of advantages. In current work, silver nanoparticles (AgNPs) have been synthesized using the extract of Fragaria ananassa seeds. The extract was used as a source of phytochemicals that can act as reducing and stabilizing agents. The characteristics of AgNPs were determined by UV/Visible, FTIR, SEM, XRD and Dynamic light scattering (DLS) techniques. The appearance of the distinctive absorption peak in UV-visible spectra at 430 nm confirmed the formation of AgNPs. The involvement of different bioactive functional groups with AgNPs was authenticated by FTIR studies. Particle size and morphology was confirmed by DLS, SEM and XRD analysis. The catalytic potential of AgNPs for the removal of poisonous organic dyes, brilliant green (BG) and methyl orange (MO) was also tested. Effect of different parameters including the catalyst concentration, dyes concentration and presence of different salts on the degradation of dyes was investigated. Nano-size and well-distributed nature of AgNPs, BG and MO dyes were degraded rapidly individually as well as simultaneously. The degradation process obeyed pseudo first order kinetics. Authors concluded that AgNPs synthesized using environment friendly and cost-effective method, can be used as a new tool to combat pollution caused by carcinogenic organic dyes.

Eosin Y (EY) is a toxic dye and has adverse effects on human beings as well as on aquatic organisms. During the last few decades, various methods such as physio-chemical and biological methods have been reported for the degradation of this toxic dye. Many researchers reported degradation of EY using different polymer stabilized metal nanoparticles synthesized employing green methods. Mono-metallic nanoparticles (MNPs) stabilized by polymeric systems are the most widely used tools for the degradation of many toxic dyes including EY. Characterization as well as morphology assessment of the nanoparticles is done by different analytical techniques including UV-visible, FTIR, SEM, TEM and XRD. In this review article, synthesis, characterization, chemistry of the polymeric stabilized nanoparticles has been reported. In addition, mechanism, kinetics and thermodynamics of catalytic degradation of EY using polymeric stabilized nanoparticles, have been discussed. This review also carries the discussion on various nano catalytic systems which have been used for the degradation of EY to link the most recent work on water purification from EY dye. This review will be helpful in understanding the spectrum of already published work describing role of polymeric stabilized nanoparticles for EY degradation. It will also motivate researchers to design their future work and commercial applications of polymeric stabilized nanoparticles.

The ineptitude of conventional water management systems to eradicate noxious compounds leads to the development of advanced treatment systems. The disclosure of graphene-based photocatalytic degradation for the eradication of phenolic compounds has become the "apple of the eye" for many researchers. This review article describes the advanced research progress during the period of 2008-2021 in graphene-based nanocomposites and discusses their different synthesis methods. We will also talk about the applications of nanocomposite in water splitting, dye degradation, solar fuel generations, and organic transformations. Multicomponent heterojunction structure, co-catalyst cohering, and noble metal coupling have been inspected to enhance the photocatalytic performance of graphene-based composite by increasing charge separation and stability. The photocatalytic system's remarkable stability has been described in terms of facile recyclability. The adsorption ability of phenolic compounds has been addressed in the form of Langmuir and Freundlich adsorption isotherm with various factors (pH, concentration, the intensity of light, the effect of catalyst, the effect of time, etc.). The purpose of this review is to survey mechanisms and processes that enlist graphene-based composite in terms of efficacy and dose of catalyst required to attain 99% degradation. Nanoparticles may cause toxicity and a pretext for their toxicity has been mentioned. Finally, it is anticipated that this article could allocate consequential knowledge to fabricating graphene-based composites that are in crucial demand of being discussed in future research.

The enhanced applications of Schiff bases metal complexes of amino acid derivatives have captured the attention of researchers for the synthesis of leucine derivatives of Schiff bases metal complexes. Amino acids are considered to be essential part of food supplements as well as derivatives of Schiff bases in coordination chemistry due to their donor ability. The leucine derivatives Schiff bases ligand have been synthesized by condensation reaction between amine of leucine with aldehyde or ketone bearing molecules attached with them. These complexes were characterized by different spectroscopic tools in order to confirm their structural geometries. The structural geometries are considered to be very important in order to improve the antimicrobial potential of leucine derivative metal complexes. By taking into account the antimicrobial potential of titled compounds, a comprehensive review of leucine derivatives of Schiff bases metal complexes has been compiled.

The study intends to find out how university teachers and students perceive students' learning in online and face-to-face classrooms. The study's participants were all university of Sargodha faculty and students. The data were collected from 15 teachers and 60 students of three selected departments of the University of Sargodha through two separate online interview schedules. It was concluded that the majority of the teachers and students were less satisfied with online learning as compared to face-to-face learning. They highlighted some serious challenges which they faced during online classes, i.e., communication gap between teacher and students, lack of internet connectivity, lack of student environment, lack of timing, difficulty in monitoring and controlling students' behavior,background distraction and difficulties in the assessment of students. However, the students and teachers supported that online education should be adopted in future after addressing it in the curriculum properly and coping with technology and internet problems. The study will provide empirical evidence to the higher education commission (HEC) and university authorities for the improvement of curriculum and provision of proper facilities for online learning.

Aloe vera contains 99-99.5% water; the remaining (0.5- 1.0%) solid material is comprised of minerals, water & fat-soluble vitamins, amino acids, phenolic compounds, simple and complex polysaccharides and organic acids. Aloe gel contains different elements like B, Be, Al, P, Si, Ca, Mg, Na and Fe. On the basis of dry-weight, the rind and pulp contain only a minor fraction of proteins and lipids. Gel polysaccharides of Aloe vera are comprised of linear chains of glucose and mannose molecules. Aloe vera consists of more than 200 different biological and medicinal active ingredients which are highly beneficial for human health. The plant demonstrates the antibacterial and antifungal, anti-helmenthic, purgative, anti-inflammatory, aphrodisiac, antispectic, anti-oxiant and laxative properties and is also used to treat skin infections, skin cancer, minor cuts and even sunburns; it is also effective against piles, jaundice, cough, dyspnea and asthma. The plant is commonly used at local level in Pakistan, for the treatment of numerous human diseases. Aloe vera also finds very important applications in cosmetics, dermatological industry, beauty products, sun block lotions, skin smoothening moisturizers, skin tonics against pimples and also have the ability to transport healthy substances through the skin and removal of dead skin cells. The present study was aimed to review the phytochemical composition and medicinal potential of Aloe barbadensis (Aloe vera) which is a very famous plant all over the world.

In the current study, cellulose/MoS2/GO nanocomposite has been synthesized by a hydrothermal method. Reports published regarding efficiency of Mo and graphene oxide-based nanocomposites for environmental remediation motivated to synthesize cellulose supported MoS2/GO nanocomposite. Formation of nanocomposite was initially confirmed by UV-visible and FTIR spectroscopic techniques. Particle size and morphology of the nanocomposite were assessed by scanning electron microscopy (SEM), and it was found having particle size ranging from 50 to 80 nm and heterogeneous structure. The XRD analysis also confirmed the structure of the nanocomposite having cellulose, MoS2, and GO. The synthesized nanocomposite was further tested for biomolecule protective potential employing different radical scavenging assays. Results of radical DPPH● (50%) and ABTS●+ (51%) scavenging studies indicate that nanocomposites can be used as a biomolecule protective agent. In addition, nanocomposite was also evaluated for photocatalytic potential, and the results showed excellent photocatalytic properties for the degradation of 4-nitrophenol up to 75% and methylene blue and methyl orange up to 85% and 70%, respectively. So, this study confirmed that cellulose supported/stabilized MoS2/GO nanocomposite can be synthesized by an ecofriendly, cost-effective, and easy hydrothermal method having promising biomolecule protective and photocatalytic potential.

This study focuses the attention on clean energy and low-carbon materials as key enablers in circular economy (CE) transition and a more sustainable path of human development. Environmentally sustainable and socially inclusive economic growth has been suggested by the United Nations Sustainable Development Goals since 1990s. Diverse stakeholders including governments, companies, international organizations, and scientific community are taking action in favor of the CE model. The long-sought sustainable development and CE goals encompass all endeavors of human beings. Currently clean energy transition is well defined in a broader global policy framework in many countries and areas to tackle the climate challenges, whereas materials with a low-carbon footprint are receiving less attention. This opinion article is aimed at critically reviewing the genesis; enabling conditions, some applications, and descriptions of low-carbon materials; and suggesting a way forward along with policy implications.

The presence of pollutants in waste water is a demanding problem for human health. Investigations have been allocated to study the adsorptive behavior of graphene-based materials to remove pollutants from wastewater. Graphene (GO) due to its hydrophilicity, high surface area, and oxygenated functional groups, is an effective adsorbent for the removal of dyes and heavy metals from water. The disclosure of green synthesis opened the gateway for the economic productive methods. This article reveals the fabrication of graphene-based composite from aloe vera extract using a green method. The proposed mechanism of GO reduction via plant extract has also been mentioned in this work. The mechanism associated with the removal of dyes and heavy metals by graphene-based adsorbents and absorptive capacities of heavy metals has been discussed in detail. The toxicity of heavy metals has also been mentioned here. The Polyaromatic resonating system of GO develops significant π-π interactions with dyes whose base form comprises principally oxygenated functional groups. This review article illustrates a literature survey by classifying graphene-based composite with a global market value from 2010 to 2025 and also depicts a comparative study between green and chemical reduction methods. It presents state of art for the fabrication of GO with novel adsorbents such as metal, polymer, metal oxide and elastomers-based nanocomposites for the removal of pollutants. The current progress in the applications of graphene-based composites in antimicrobial, anticancer, drug delivery, and removal of dyes with photocatalytic efficacy of 73% is explored in this work. It gives a coherent overview of the green synthesis of graphene-based composite, various prospective for the fabrication of graphene, and their biotoxicity.

Corynebacterium glutamicum is an authenticated microorganism that supports amino acid production consistent with dietary importance. Fermentation parameters like temperature, agitation speed, and carbon source concentration were optimized using response surface methodology. Surface response model suggested that optimal fermentation parameters including 30°C, 50 g/L glucose concentration, and shaking speed of 120 rpm furnished 14.2 g/L of glutamic acid and 5.1 g/L lysine, comparable with the predicted values. After optimizing fermentation parameters in shake flasks, the fermentation kinetics was studied in a stirred fermenter. The kinetic study revealed that the substrate consumption rate achieved a maximum level of 3.36 g/L/hour between 12 and 18 hours; afterwards, it decreased and fell to 1.9 g/L/hour. Average biomass yield over a period of 48 hours was 0.337 g/L; however, maximum biomass yield of 0.51 g/L was noted between 10 and 20 hours. Overall molar yield coefficient of CO2 ( Y C CO 2 / S ) was found to be 0.234. The molar yield coefficient of biomass ( Y C X / S ) was 0.6 in exponential phase which decreased afterwards. This study indicates that the average biomass yield over a time of 48 hours was 0.337 g/L, with a maximum yield within 10 to 20 hours obtained under optimized conditions. The molar yield coefficient of CO2 ( Y C CO 2 / S ) was found to be 0.234. The molar yield coefficient of biomass ( Y C X / S ) was 0.6 in exponential phase which decreased and fell to near zero at 48 hrs.

Cabbage white butterfly (Pieris brassicae) is one of the important insect pests of cabbage crop which causes remarkable quantitative or qualitative crop losses. The research was conducted at Hazara Agricultural research station, Abbottabad (Pakistan) to study the effect of different new chemical insecticides, botanical oil and neem seed oil (Azadirachta indica A. Juss.) on the population density of P. brassicae. The study showed that neem oil had a significant effect on population of P. brassicae in comparison to control treatment. So, neem oil alone or in combination with insecticides can be used for control of P. brassicae in vegetable crops for a safer food supply.

The purpose of this study was to identify the challenges to fair assessment in semester examination system, their causes and the solutions. One hundred and forty-four (144) university teachers were interviewed and 48 focus group discussions were conducted among the BS students in six public universities of the Punjab (Pakistan). The data were analyzed through thematic analysis technique. Findings of the study revealed that, in order to judge novice teachers’ competence in assessment, universities did not ask for a professional teaching certification. Most of the university teachers appeared to be in need of having more competence in developing question papers and using different assessment techniques. Moreover, there was no proper mechanism of conduction and inservice training for the enhancement of teachers’ essential skills for the fair assessment of students’ learning outcomes. The course outlines were not covered completely within the stipulated time. Additionally, the university teachers had to perform multiple departmental duties, beside their teaching activities, compelling them compromises their classes. By force of circumstance, they teach and assess selective parts of the course outlines. The respondents suggested the development of a proper training mechanism for university teachers to make them capable of doing fair assessment and provision of required resources.

Herrin, a simple and eco-friendly method for the synthesis of silver nanowires (Ag-NWs) has been reported. Silver nanowires were synthesized using Psidium guajava seed extract that acted as a reducing agent as well as a stabilizing agent for silver nitrate solution. Synthesis was carried out at 50 °C temperature under continuous UV-irradiation. Silver nanowires were initially characterized by a UV-visible and FTIR spectrophotometer. In addition, morphology and particle size of synthesized Ag-NWs were determined using Field Emission Scanning Electron Microscopy and X-ray diffraction (XRD) techniques. Nanowires were found to have 12.8 μm length and 200–500 nm diameter and cubic phase morphology. Furthermore, the catalytic potential of Ag-NWs for the degradation of methyl orange dye (MO) was determined. The selected dye was degraded successfully that confirmed the catalytic potential of Ag-NWs. The authors concluded that Ag-NWs can be synthesized using plant extract having excellent morphological features as well as impressive catalytic potential.

Current work describes green synthesis of Fe, Mn (monometallic) and Fe-Mn (bimetallic) nanoparticles using Cannabis sativa leaf extract as stabilizing and capping agent. In order to assess the formation of nanoparticles UV/Vis and FTIR analysis was carried out. In addition, Scanning electron microscopy and XRD studies confirmed synthesis as well as morphology of the nanoparticles. All the nanoparticles were found having particle size 20–80 nm and crystallite 3–20 nm. Photocatalytic activity of synthesized nanoparticles has been evaluated by carrying out degradation of two dyes methyl orange (MO) and Congo red (CR) in the presence of nanocatalysts. Degradation of both the dyes was carried out separately using Fe, Mn and Fe-Mn nanoparticles to compare the efficiency of monometallic with bimetallic nanoparticles. Iron and manganese monometallic particles have completely degraded MO in 18 min and 20 min and CR in 24 min and 18 min respectively. However, due to increased synergistic effect Fe-Mn BNPs completely degraded MO dye in just 12 min and CR in 14 min. In nutshell, this work is actually a step towards the synthesis of bimetallic nanoparticles using a plant extract with improved synergistic photocatalytic activities which impart various properties to the designed nanomaterial.

Copper-nickel bimetallic nanoparticles (Cu-Ni BNPs) were fabricated using an eco-friendly green method of synthesis. An extract of synthesized Gazania rigens was used for the synthesis of BNPs followed by characterization employing different techniques including UV/Vis spectrophotometer, FTIR, XRD, and SEM. Spectrophotometric studies (UV-Vis and FTIR) confirmed the formation of bimetallic nanoparticles. The SEM studies indicated that the particle size ranged from 50 to 100 nm. Analysis of the BNPs by the XRD technique confirmed the presence of both Cu and Ni crystal structure. The synthesized nanoparticles were then tested for their catalytic potential for photoreduction of methylene blue dye in an aqueous medium and DPPH radical scavenging in a methanol medium. The BNPs were found to be efficient in the reduction of methylene blue dye as well as the scavenging of DPPH free radicals such that the MB dye was completely degraded in just 17 min at the maximum absorption of 660 nm. Therefore, it is concluded that Cu-Ni BNPs can be successfully synthesized using Gazania rigens extract with suitable size and potent catalytic and radical scavenging activities. Validerad;2021;Nivå 2;2021-09-27 (alebob);Funder: King Saud University, Riyadh, Saudi Arabia (RSP-2021/243)

Iron–copper bimetallic nanoparticles (Fe-Cu BNPs) were prepared via a green synthesis route. Ixora finlaysoniana has been used in this study as a capping and stabilizing agent in the modification of Fe-Cu BNPs. As-synthesized BNPs were characterized using different techniques including UV/Vis spectrophotometry, FTIR, XRD and SEM. A particle size analyzer and SEM studies indicated the particle size to be in the range of 50–200 nm. In addition, degradation of MB dye in an aqueous system and radical-scavenging potential in a DPPH assay were also examined using BNPs. Methylene blue dye degradation in 17 min was monitored with UV/Vis spectrophotometry, which exhibited the efficiency of Fe-Cu BNPs. Bimetallic nanoparticles were also found to be efficient in neutralizing DPPH free radicals. Furthermore, kinetic studies of both dye degradation and radical scavenging potential are reported in this article. Subsequently, Fe-Cu BNPs synthesized via a green and sustainable method can be employed for dye degradation and free radical-scavenging activities.