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The present study demonstrates the hydrothermal synthesis of SnO

In this study, cadmium sulfide (CdS) quantum dots (QDs) and barium (Ba) (3 and 6 wt %)-doped CdS QDs were synthesized via a hydrothermal technique. The basic purpose of this work is to degrade methylene blue (MB) dye and evaluate density functional theory (DFT). The synthesized samples were characterized through X-ray powder diffraction (XRD), selected area electron diffraction (SAED), Fourier transform infrared spectroscopy (FTIR), scanning electron microscope (SEM), high-resolution transmission electron microscopy (HR-TEM), UV-vis spectrophotometer, PL, and density functional theory (DFT). The XRD (structural analysis) confirmed that the hexagonal crystal structure and crystallinity increased upon doping. Selected area electron diffraction (SAED) analysis confirmed the polycrystalline nature of the prepared QDs. The functional groups have been investigated using FTIR analysis. The surface and structural morphologies of the synthesized specimen have been investigated by applying TEM and FE-SEM, and it was found to exhibit the topology of QDs. In addition, optical characteristics have been investigated via UV-vis absorption spectroscopy, which exhibited a bathochromic shift (red shift) as a consequence of the reduction of the band-gap energy upon doping from 2.56 to 2.38 eV. PL analysis was used to observe the electron-hole recombination rate. Moreover, the electronic and optical properties of Ba-doped CdS were further explored using density functional theory. Pristine and Ba-doped QDs exhibit sufficient catalytic activity (CA) against the MB dye in all media as 62.59, 70.15, and 72.74% in neutral, basic, and acidic solutions, respectively.

The aim of this work was to investigate the influences of different concentrations of Ag3PO4 aqueous dispersion by measuring the bacteriostatic characteristic against bacteria E. coli. The Ag3PO4 particles were successfully synthesized by precipitation method. Then, the morphological, structural and chemical compositional analyses were characterized by scanning electron microscopy (SEM) and transmission electron microscopy (TEM), X-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FTIR), respectively. All these analyses confirmed the formation of Ag3PO4 particles with the shape of nearly spherical with a size of 100 – 700 nm. Meanwhile, Kirby-Bauer disk diffusion susceptibility test was chosen to determine the sensitivity of E. coli to antibacterial compounds in Ag3PO4 particles. The results showed that the antibacterial ability was significantly improved by increasing the concentration of Ag3PO4 aqueous dispersion, and the best concentration was 600 mg /mL. This study suggested that Ag3PO4 particles can be exploited as an effective candidate for antibacterial agents.

Dolomite has great potential to be employed as filler or nanofiller in polymer composite/nanocomposite system. However, the research on dolomite as filler or nanofiller in polymer composite is still immature, requiring further investigations on how to optimize the dispersion of the dolomite in the polymer matrix, thus improving its properties. Particle size reduction of dolomite can be an efficient approach to increase its surface area and facilitate its dispersion and distribution within polymer matrix in order to develop homogeneous composite/nanocomposite system. In this study, the dolomite in pulverized form was obtained from Perlis Dolomite Industry, Malaysia with the average particle size of 150μm. In order to reduce the size of this dolomite, we have initially employed the planetary ball milling method. Results indicate that the particle size of dolomite has been reduced from 150μm to 2μm after subjected to ball milling process. This shows that upon ball milling procedure, the size of dolomite particle is still in micronmeter. Next, the ball milled dolomite was subjected to tip-sonication process to obtain dolomite in nanosize range. Several tip-sonication parameters, which were; amplitude and number of sonication repetition were applied in order to select the best parameters that can produce the finest dolomite powder. SEM and TEM were used to characterize the microstructure of the raw dolomite and the size reduced dolomite. Our results show that when the ball milled dolomite was tip-sonicated, much smaller particle size was obtained. Dolomite with the smallest particle size (~200nm) was obtained when the tip-ultrasonication was performed 3 times at amplitude of 50. These findings indicate that the combination of ball milling and tip-sonication is an efficient method to produce very fine dolomite particles, up to nanosize range. Furthermore, it is a clean, simple method and not involved any toxic and harmful chemicals.

This study examined the catalytic and bactericidal properties of polymer-doped copper oxide (CuO). For this purpose, a facile co-precipitation method was used to synthesize CuO nanostructures doped with CS-g-PAA. Various concentrations (2, 4, and 6%) of dopants were systematically incorporated into a fixed amount of CuO. The prepared samples were analyzed by different optical, structural, and morphological characterizations. Field emission scanning electron microscopy and transmission electron microscopy micrographs indicated that doping transformed CuO's agglomerated rod-like surface morphology to form nanoflakes. UV-vis spectroscopy revealed that the optical spectra of the samples exhibit a redshift after doping, leading to a decrease in band gap energy from 3.3 to 2.5 eV. The purpose of the study was to test the catalytic activity of pristine and CS-g-PAA doped CuO for the degradation of methylene blue in acidic, basic, and neutral conditions using NaBH

In this study, MgO-doped CNC-g-PAA hydrogel was synthesized by grafting poly (acrylic acid) (PAA) onto cellulose nanocrystals (CNC) and then doped Magnesium oxide (MgO) using pH 7.0 and 12.0 to obtain an efficient nanocomposite hydrogel for antibacterial and anti-cancer activities. The synthesized nanocomposite hydrogels were evaluated by detailed characterization and confirmed the formation of a well-interconnected porous structure. MgO/CNC-g-PAA (pH = 12.0) exhibited improved bactericidal tendencies towards gram-negative and gram-positive bacteria, which was further investigated by in-silico molecular docking analyses and also examined the reactive oxygen species production by photocatalysis and free radical-scavenging assay. After this, Doxorubicin (DOX), a model anticancer drug, was successfully loaded into nanocomposites (∼79 %) by electrostatic interaction and confirmed pH-triggered based release, which was over 53.7 % in 24 h. Finally, in vitro cytotoxicity-based analysis confirmed the improved antitumor efficacy of nanocomposite hydrogels. These findings revealed that MgO/CNC-g-PAA hydrogels might be prospective carriers for controlled drug delivery.

The removal of hazardous pollutants from water is becoming an increasingly interesting topic of research considering their impact on the environment and the ecosystem. This work was carried out to synthesize graphitic carbon nitride (g-C

Nb/starch-doped ZnO quantum dots (QDs) were prepared by a coprecipitation route. A fixed quantity of starch (st) and different concentrations (2 and 4%) of niobium (Nb) were doped in a ZnO lattice. To gain a better understanding of synthesized nanostructures, a systematic study was carried out utilizing several characterization methods. The goal of this research was to undertake methylene blue (MB) dye degradation with a synthetic material and also study its antibacterial properties. The phase structure, morphology, functional groups, optical properties, and elemental compositions of synthesized samples were investigated. Our study showed that ZnO QDs enhanced photocatalytic activity (PCA), resulting in effective MB degradation, in addition to showing good antimicrobial activity against Gram-negative relative to Gram-positive bacteria. Molecular docking study findings were in good agreement with the observed

Fish processing by-products, such as fish bone waste is usually considered as waste and will be disposed without fully utilizing it. Indeed, this by-product can serve as a cheap bio-resource for the production of high-value product, for instance, as an inexpensive source of calcium phosphate material. In this research, Lutjanus johnii and Lutjanus sebae bones were subjected to thermal calcination to yield different calcium phosphate products. XRD, FTIR and HRTEM-SAED results revealed that biphasic HAp/β-TCP mixture was obtained by heat treatment of Lutjanus johnii bone while a single-phase HAp was prepared from Lutjanus sebae bone. In addition, it was shown that both Lutjanus johnii and Lutjanus sebae bones had a merit in producing B-type carbonated composition that is advantageous for biomedical application. EDX result further corroborated the existence of inorganic elements such as Mg, Na and Sr. With their unique composition, the calcined products deriving from Lutjanus johnii and Lutjanus sebae bones can be further employed to form bioceramic scaffolds for bone engineering applications.

In present study, control sized cadmium sulphide (CdS) quantum dots (QDs) and cellulose nanocrystals grafted polyvinylpyrrolidone (CNC-g-PVP) doped CdS QDs were synthesized via co-precipitation. The suggested pathway is fruitful in throwing out organic pollutants like methylene blue (MB) from industrial water and bactericidal applications. A series of characterization techniques were used to determine the structural, optical and morphological qualities of prepared samples. The X-ray diffraction (XRD) pattern verified hexagonal structure with no significant change occurring in the spectrum upon doping (2, 4, and 6 %). The UV-vis spectrophotometer describes blueshift in absorption pattern, resulting in an increase in band gap energy (E

This research work intends to evaluate the photoactivity of calcium oxide (CaO) nanorods (NRs) doped with cellulose nanocrystals (CNCs) and cerium (Ce). CNC-doped CaO and Ce/CNC codoped CaO were synthesized via the sol-gel technique. Structural, optical, morphological, physiochemical, phase constitution, and functional group evaluations were performed. The photodegradation of the prepared nanostructures was analyzed by observing photodegradation of a mixture of methylene blue and ciprofloxacin dye under light irradiation. The photocatalytic activity of the dye was drastically enhanced upon codoping in CaO. For both

A ZnCo2O4/Ag3PO4 nanocomposite with high photocatalytic activity against pollutants and pathogens was sonochemically prepared, characterized using various techniques and simulated computationally.

In this research, various concentrations of molybdenum (2, 4 and 6 wt%) doped Fe3O4 nanostructures (Mo-Fe3O4 NSs) were prepared via a co-precipitation technique.

Sustainable renewable energy production is being intensely disputed worldwide because fossil fuel resources are declining gradually. One solution is biodiesel production

The phase formation behavior of β′-SiAlON with the general formula Si6-zAlzOzN8-z was studied comprehensively for z values from 1 to 3 using spark plasma sintering (SPS) as the consolidation technique at synthesis temperatures from 1400 to 1700 °C. The samples were prepared close to the β′-SiAlON composition line: Si3N4 − 4/3(AlN·Al2O3) in the phase diagram using (A) nano-sized amorphous Si3N4 and (B) micro-sized β-Si3N4 precursors. Field-emission scanning electron microscopy (FESEM) was used for microstructural analysis. Most compositions reached almost full density at all SPS temperatures. Compared with the micro-sized β-Si3N4 precursor, the nano-sized amorphous Si3N4 precursor accelerated the reaction kinetics, promoting the formation of dense β′-SiAlON + O′-SiAlON composites after SPS at synthesis temperatures of 1400–1500 °C. This resulted in very high values of Vickers hardness (Hv10) = 18.2–19.2 GPa for the z = 1 composition related to the hardness of the O′-SiAlON component phase. In general, for samples synthesized from nano-sized amorphous Si3N4, which were almost fully dense, containing >95% β′-SiAlON, the hardness values were 13.4–13.8 GPa with a fracture toughness of 3.5–4.6 MPa m1/2. For equivalent samples synthesized from micro-sized β-Si3N4, hardness was in the range 13.9–14.4 GPa with a fracture toughness of 4.3–4.5 MPa.m1/2. These values are comparable with fully dense β′-SiAlONs, usually containing intergranular glass phase which has been sintered by HIP and other processes at much higher temperatures for longer times.

Surface functionalized magnetoelectric core–shell cobalt ferrite barium titanate nanorods (CFO@BTO NRs) offer efficient magnetic field assisted drug delivery in cancer cells, resulting in enhanced cytotoxicity.

Frequent exposure to ultraviolet (UV) radiation without any protection turns out to be a fatal threat leading to skin cancer, necessitating the use of sunscreen cosmetic product with enhanced efficiency to dissipate the UV absorbed energy.

Figure showing bactericidal mechanism exhibited by the prepared pristine and co-doped SnO2.

Cellulose nanocrystals (CNCs) and molybdenum disulphide (MoS2) incorporated into ZnO nanorods (NRs) were synthesized via a chemical precipitation route at room temperature. All concerned samples were characterized to examine their optical properties, elemental composition, phase formation, surface morphology and functional group presence. The aim of this research was to enhance the catalytic properties of ZnO by co-doping with various concentrations of CNCs and MoS2 NRs. It was renowned that doped ZnO NRs showed superior catalytic activity compared to bare ZnO NRs. Statistically significant (p < 0.05) inhibition zones for samples were recorded for E. coli and S. aureus at low and high concentrations, respectively. The in vitro bactericidal potential of ZnO-CNC and ZnO-CNC-MoS2 nanocomposites was further confirmed through in silico molecular docking predictions against the DHFR and DHPS enzymes of E. coli and S. aureus. Molecular docking studies suggested the inhibition of these enzyme targets by CNC nanocomposites as a possible mechanism governing their bactericidal activity.

The figure shows a schematic of the photocatalytic mechanism of Ba-doped TiO2 QDs.

In this study, different concentrations (0, 0.02, 0.04, and 0.06 wt%) of Mo doped onto La2O3 nanostructures were synthesized using a one-pot co-precipitation process.

Graphene oxide (GO) and cellulose nanocrystal (CNC)-doped TiO2 quantum dots (QDs) were effectively synthesized by employing the co-precipitation method for the degradation of dyes and antimicrobial applications.

In this study, poly(isobutylene-alt-maleic anhydride) (PMA)-coated spinel ferrite (MFe2O4, where M = Fe, Co, Ni, or Zn) nanoparticles (NPs) were developed as carriers of the anticancer drugs doxorubicin (DOX) and methotrexate (MTX). Physical characterizations confirmed the formation of pure cubic structures (14–22 nm) with magnetic properties. Drug-loaded NPs exhibited tumor specificity with significantly higher (p < 0.005) drug release in an acidic environment (pH 5.5). The nanoparticles were highly colloidal (zeta potential = −35 to −26 mV) in deionized water, phosphate buffer saline (PBS), and sodium borate buffer (SBB). They showed elevated and dose-dependent cytotoxicity in vitro compared to free drug controls. The IC50 values ranged from 0.81 to 3.97 μg/mL for HepG2 and HT144 cells, whereas IC50 values for normal lymphocytes were 10 to 35 times higher (18.35–43.04 µg/mL). Cobalt ferrite (CFO) and zinc ferrite (ZFO) NPs were highly genotoxic (p < 0.05) in cancer cell lines. The nanoparticles caused cytotoxicity via oxidative stress, causing DNA damage and activation of p53-mediated cell cycle arrest (significantly elevated expression, p < 0.005, majorly G1 and G2/M arrest) and apoptosis. Cytotoxicity testing in 3D spheroids showed significant (p < 0.05) reduction in spheroid diameter and up to 74 ± 8.9% of cell death after two weeks. In addition, they also inhibited multidrug resistance (MDR) pump activity in both cell lines suggesting effectivity in MDR cancers. Among the tested MFe2O4 NPs, CFO nanocarriers were the most favorable for targeted cancer therapy due to excellent magnetic, colloidal, cytotoxic, and biocompatible aspects. However, detailed mechanistic, in vivo cytotoxicity, and magnetic-field-assisted studies are required to fully exploit these nanocarriers in therapeutic applications.

Corrosion is the primary cause of failure of heat exchangers in industry, especially in the oil and petrochemical sector. The modes of failure related to corrosion include erosion corrosion, pitting corrosion, crevice corrosion, grain boundary corrosion, dealloying, galvanic corrosion, stress corrosion cracking, waterside corrosion, uniform corrosion, and microbially induced corrosion. Primary causes of corrosion-related failures were found to be fabrication and welding defects, presence of residual stresses, inappropriate materials selection and design, improper water chemistry/flow and poor choice of filters, presence of corrosive species such Cl−, Sx−, O2, NH4 + in water, nonadherence to recommended operating conditions, and noncompliance with standard practices during the shutdown. This article is a review covering only corrosion-related failures in heat exchangers.

Novel Au and cellulose nanocrystals (CNC)-doped SrO nanocomposites have been fabricated using simple and cost-effective chemical co-precipitation technique. Various concentrations of Au were doped into fixed amounts of CNC and SrO nanocomposites. The objective of this triplex nanocomposite was to examine the effect of incorporating dopants in SrO on the efficient elimination of organic contaminants from water and their antibacterial potential with molecular docking study. Adequate experimental conditions such as temperature, suitable volume ratio of reactants and pH were generated during the synthesis. For comparative studies, nanocomposites were evaluated through a number of characterization tools. The structural and morphological analysis through XRD and HR-TEM revealed the cubic crystalline structure of aggregated SrO quantum dots (QDs). Furthermore, an interconnected chain-like structure of nanoclusters was observed upon CNC and Au incorporation in SrO lattice. The size of nanoclusters/nanoparticles was calculated to be approximately 30 nm which matched well with the reported literature. Reduction in crystallinity and bandgap from 4.12 eV (for pristine SrO) to 3.8 eV was observed upon co-doping with CNC and Au in SrO lattice. Furthermore, pH-based catalytic analysis of prepared nanocomposites revealed 98% dye degradation (in acidic media) against methylene blue ciprofloxacin (MBCF) dye along with good bactericidal activities against Gram-positive/negative bacteria, respectively. In silico molecular docking analysis for enzyme targets belonging to cell wall synthesis (penicillin-binding protein 4) and fatty acid synthesis (enoyl-[acyl-carrier-protein] reductase) suggested Au–CNC and Au/CNC-doped SrO nanostructures as possible inhibitors of these enzymes owing to their good binding scores and binding interactions with active site residues. (a) Preparation of cellulose nanocrystals (CNC) by acid hydrolysis. (b) Schematic synthesis route to fabricate Au/CNC–SrO nanocomposites.

Graphene oxide (GO)-doped MnO2 nanorods loaded with 2, 4, and 6% GO were synthesized via the chemical precipitation route at room temperature. The aim of this work was to determine the catalytic and bactericidal activities of prepared nanocomposites. Structural, optical, and morphological properties as well as elemental composition of samples were investigated with advanced techniques such as X-ray diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy, UV–visible (vis) spectroscopy, photoluminescence (PL), energy-dispersive spectrometry (EDS), and high-resolution transmission electron microscopy (HR-TEM). XRD measurements confirmed the monoclinic structure of MnO2. Vibrational mode and rotational mode of functional groups (O–H, C=C, C–O, and Mn–O) were evaluated using FTIR results. Band gap energy and blueshift in the absorption spectra of MnO2 and GO-doped MnO2 were identified with UV–vis spectroscopy. Emission spectra were attained using PL spectroscopy, whereas elemental composition of prepared materials was recorded with scanning electron microscopy (SEM)-EDS. Moreover, HR-TEM micrographs of doped and undoped MnO2 revealed elongated nanorod-like structure. Efficient degradation of methylene blue enhanced the catalytic activity in the presence of a reducing agent (NaBH4); this was attributed to the implantation of GO on MnO2 nanorods. Furthermore, substantial inhibition areas were measured for Escherichia coli (EC) ranging 2.10–2.85 mm and 2.50–3.15 mm at decreased and increased levels for doped MnO2 nanorods and 3.05–4.25 mm and 4.20–5.15 mm for both attentions against SA, respectively. In silico molecular docking studies suggested the inhibition of FabH and DNA gyrase of E. coli and Staphylococcus aureus as a possible mechanism behind the bactericidal activity of MnO2 and MnO2-doped GO nanoparticles (NPs).

Global population growth and accelerated urbanisation have resulted in massive amounts of fossil fuel use and waste production. Because of its high energy content, pure nature, and fuel quality, hydrogen fuel is a viable option to fossil fuels. Biohydrogen from agricultural waste, in particular, piques concern because it generates hydrogen while still disposing of waste. This review conducted a bibliometric analysis of biohydrogen production from organic waste to trace the research trends and hotspots based on the literature in the Web of Science (WOS) database from 1970 to 2020. The present review article also focuses on highlighting various processes for converting organic waste into hydrogen, raw materials for biohydrogen production, and catalysts that could distil the latest perceptions that could shed light on a route advancing for successful catalyst design. It also seems that some intentions have been paid on studying waste materials such as pure polysaccharides, disaccharides, and monosaccharides. Among all the catalysts used, non-noble and low-cost active metals over reduced graphene oxide (rGO) support can significantly affect the activity of fermentative hydrogen production from organic waste materials. However, researches focusing on developing anaerobic membrane bioreactors for these technologies are still needed.

In this work, aluminum/starch (St)-doped CaO nanoparticles (NPs) were synthesized by a co-precipitation method to degrade harmful dyes in various pH media. Systematic characterization was performed to investigate the influence of Al/St dopants on the composition, crystal structure, functional groups present, optical characteristics, and morphology of CaO NPs. Further hybrid density functional analyses corroborated that the band gap energy was reduced as the Al concentration in starch-doped CaO is increased. Optical absorption spectra of the synthesized materials revealed a redshift upon doping, which indicated depletion in the band gap energy of Al/St-doped CaO. PL spectroscopy showed that the intensity of CaO was reduced by the incorporation of Al and St assigned to minimum electron-hole pair recombination. Interlayer spacing and morphological features were determined by HR-TEM. HRTEM revealed that the control sample has cubic NPs and the incorporation of St showed overlapping around agglomerated NPs. The

Different concentrations (2 and 4 wt%) of graphite carbon nitride (g-C