Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 20 de 55
Filter
1.
Chemosphere ; 360: 142408, 2024 Jul.
Article in English | MEDLINE | ID: mdl-38789056

ABSTRACT

A massive amount of toxic substances and harmful chemicals are released every day into the outer environment, imposing serious environmental impacts on both land and aquatic animals. To date, research is constantly in progress to determine the best catalytic material for the effective remediation of these harmful pollutants. Hybrid nanomaterials prepared by combining functional polymers with inorganic nanostructures got attention as a promising area of research owing to their remarkable multifunctional properties deriving from their entire nanocomposite structure. The versatility of the existing nanomaterials' design in polymer-inorganic hybrids, with respect to their structure, composition, and architecture, opens new prospects for catalytic applications in environmental remediation. This review article provides comprehensive detail on catalytic polymer nanocomposites and highlights how they might act as a catalyst in the remediation of toxic pollutants. Additionally, it provides a detailed clarification of the processing of design and synthetic ways for manufacturing polymer nanocomposites and explores further into the concepts of precise design methodologies. Polymer nanocomposites are used for treating pollutants (electrocatalytic, biocatalytic, catalytic, and redox degradation). The three catalytic techniques that are frequently used are thoroughly illustrated. Furthermore, significant improvements in the method through which the aforementioned catalytic process and pollutants are extensively discussed. The final section summarizes challenges in research and the potential of catalytic polymer nanocomposites for environmental remediation.


Subject(s)
Environmental Pollutants , Environmental Restoration and Remediation , Nanocomposites , Polymers , Environmental Restoration and Remediation/methods , Catalysis , Polymers/chemistry , Environmental Pollutants/chemistry , Nanocomposites/chemistry , Oxidation-Reduction
2.
J Surg Case Rep ; 2024(1): rjad734, 2024 Jan.
Article in English | MEDLINE | ID: mdl-38283410

ABSTRACT

Intussusception is a phenomenon commonly associated with the paediatric population. In adults, intussusception is frequently a result of a neoplastic process. We present the case of a 56-year-old gentleman who was diagnosed to the local Emergency Department with a 4-day history of worsening severe, left sided lower abdominal pain. The pain was colicky in nature. Computed tomography identified a long-segment intussusception involving distal small bowel, caecum, ascending colon, the entirety of transverse colon and its associated mesentery. The patient proceeded to theatre where a laparotomy and right hemicolectomy was performed. Histopathological analysis of the specimen identified an ileal myxoma as the lead-point of the intussusception. This report emphasises the value of prompt investigation in atypical clinical presentations.

3.
Sci Total Environ ; 913: 169489, 2024 Feb 25.
Article in English | MEDLINE | ID: mdl-38159747

ABSTRACT

Globally recognized as emergent contaminants, microplastics (MPs) are prevalent in aquaculture habitats and subject to intense management. Aquaculture systems are at risk of microplastic contamination due to various channels, which worsens the worldwide microplastic pollution problem. Organic contaminants in the environment can be absorbed by and interact with microplastic, increasing their toxicity and making treatment more challenging. There are two primary sources of microplastics: (1) the direct release of primary microplastics and (2) the fragmentation of plastic materials resulting in secondary microplastics. Freshwater, atmospheric and marine environments are also responsible for the successful migration of microplastics. Until now, microplastic pollution and its effects on aquaculture habitats remain insufficient. This article aims to provide a comprehensive review of the impact of microplastics on aquatic ecosystems. It highlights the sources and distribution of microplastics, their physical and chemical properties, and the potential ecological consequences they pose to marine and freshwater environments. The paper also examines the current scientific knowledge on the mechanisms by which microplastics affect aquatic organisms and ecosystems. By synthesizing existing research, this review underscores the urgent need for effective mitigation strategies and further investigation to safeguard the health and sustainability of aquatic ecosystems.


Subject(s)
Microplastics , Water Pollutants, Chemical , Microplastics/toxicity , Ecosystem , Plastics , Environmental Monitoring , Water Pollutants, Chemical/analysis
4.
Front Plant Sci ; 14: 1255961, 2023.
Article in English | MEDLINE | ID: mdl-38093998

ABSTRACT

Wheat lodging is a serious problem affecting grain yield, plant health, and grain quality. Addressing the lodging issue in wheat is a desirable task in breeding programs. Precise detection of lodging levels during wheat screening can aid in selecting lines with resistance to lodging. Traditional approaches to phenotype lodging rely on manual data collection from field plots, which are slow and laborious, and can introduce errors and bias. This paper presents a framework called 'LodgeNet,' that facilitates wheat lodging detection. Using Unmanned Aerial Vehicles (UAVs) and Deep Learning (DL), LodgeNet improves traditional methods of detecting lodging with more precision and efficiency. Using a dataset of 2000 multi-spectral images of wheat plots, we have developed a novel image registration technique that aligns the different bands of multi-spectral images. This approach allows the creation of comprehensive RGB images, enhancing the detection and classification of wheat lodging. We have employed advanced image enhancement techniques to improve image quality, highlighting the important features of wheat lodging detection. We combined three color enhancement transformations into two presets for image refinement. The first preset, 'Haze & Gamma Adjustment,' minimize atmospheric haze and adjusts the gamma, while the second, 'Stretching Contrast Limits,' extends the contrast of the RGB image by calculating and applying the upper and lower limits of each band. LodgeNet, which relies on the state-of-the-art YOLOv8 deep learning algorithm, could detect and classify wheat lodging severity levels ranging from no lodging (Class 1) to severe lodging (Class 9). The results show the mean Average Precision (mAP) of 0.952% @0.5 and 0.641% @0.50-0.95 in classifying wheat lodging severity levels. LodgeNet promises an efficient and automated high-throughput solution for real-time crop monitoring of wheat lodging severity levels in the field.

5.
Environ Res ; 238(Pt 1): 117133, 2023 12 01.
Article in English | MEDLINE | ID: mdl-37729960

ABSTRACT

Removal of methyl iodide (CH3I) from the air present within nuclear facilities is a critical issue. In case of any nuclear accident, there is a great need to mitigate the radioactive organic iodide immediately as it accumulates in human bodies, causing severe consequences. Current research focuses on removing organic iodides, for which the surface of activated carbon (AC) was modified by impregnating it with different metals individually, i.e. Ag, Ni, Zn, Cu and with the novel combination of these four metals (AZNC). After the impregnation of metals, triethylenediamine (TEDA) was coated on metal impregnated activated carbon (IAC) surface. The adsorption capacity of the combination of four metals IAC was found to be 276 mg/g as the maximum for the trapping of CH3I. Whereas TEDA-metal impregnation on ACs enhanced the removal efficiency of CH3I up to 352 mg/g. After impregnation, adsorption capacity of AZNC and AZNCT is significantly higher as compared to AC. According to the finding, t5% of AZNCT IAC is 46 min, which is considerably higher than the t5% of other tested adsorbents. According to isotherm fitting data, Langmuir isotherm was found superior for describing CH3I sorption onto AC and IACs. Kinetics study shows that pseudo second order model represented the sorption of CH3I more accurately than the pseudo first order. Thermodynamic studies gave negative value of ΔG which shows that the reaction is spontaneous in nature. Based on the findings, AZNCT IAC appears to have a great potential for air purification applications in order to obtain clean environment.


Subject(s)
Charcoal , Water Pollutants, Chemical , Humans , Metals , Piperazines , Adsorption , Kinetics , Hydrogen-Ion Concentration
6.
Environ Sci Pollut Res Int ; 30(42): 95860-95874, 2023 Sep.
Article in English | MEDLINE | ID: mdl-37561304

ABSTRACT

Dilute magnetic semiconductor Zn1-xCuxO (x = 0, 1.5, 3.0, and 4.5%) nanorods were prepared by hydrothermal method. The impact of dopant concentration on the physical properties was investigated along with the anti-bacterial and photocatalytic activities. Synthesis of ZnO nanorods was confirmed by the characteristic band at 380 nm in UV-Visible spectra of the synthesized samples. A red shift in absorbance spectra was observed from 380 to 465 nm with an increase in dopant concentration. The hexagonal wurtzite geometry and rod-like morphology of Cu-doped ZnO nanorods having an average size of 29 nm were confirmed by X-ray diffraction analysis (XRD) and scanning electron microscopy (SEM), respectively. An increase in the crystallinity of the material was observed with an increase in the dopant (Cu) ratio without any alteration in geometry. EDX analysis was used to confirm the purity of samples. FTIR spectra were recorded to explore the functional group present in samples. The hysteresis loop drawn by a vibrating-sample magnetometer (VSM) was utilized to analyze the ferromagnetic behavior. As-synthesized pure and Cu-ZnO nanorods were evaluated for their photocatalytic behavior for the photodegradation of methyl orange (MO) dye. Zn1 - xCuxO with x = 4.5%, pH 3, and catalyst dosage of 0.5 g has shown the maximum efficiency. Results elucidated > 81% degradation of MO dye with a rate constant (k) value of - 1.930 × 10-2 min-1 in just 90 min of exposure to a visible light source. ZnO nanorods have also exhibited anti-bacterial potential against gram-positive and gram-negative strains of bacteria. However, smaller size nanorods were found more effective to suppress the growth of gram-negative bacteria. A slight decrease (11%) in catalytic potential was observed in the 5th cycle during recycling and reuse experiments.


Subject(s)
Nanotubes , Zinc Oxide , Light , Photolysis , Bacteria
7.
Chemosphere ; 334: 138923, 2023 Sep.
Article in English | MEDLINE | ID: mdl-37178938

ABSTRACT

Perovskites overtaking simple metal oxides as solar light harvesting material due to their excellent photocatalytic efficiency and superior stability. An efficient visible light responsive, K2Ba0.3Cu0.7O3 single perovskites oxides (SPOs) photocatalyst was fabricated by a facile hydrothermal method. The fabricated SPOs was characterized by various techniques. SEM analysis confirm the cubic morphology of SPOs, the average length and diameter of SPOs were 27.84 and 10.06 µm calculated from SEM images. FT-IR analysis confirmed the presence of M-M and M - O bonds. EDX showed prominent peaks of the constituent elements. The average crystallite size of SPOs calculated by Scherrer and Williamson-Hall equation was 14.08 and 18.47 nm respectively. The optical band gap value lies in visible region of spectrum (2.0 eV) determined from the Tauce's plot. The fabricated SPOs was applied for photocatalytic degradation of methylene blue (MB) dye. Maximum degradation 98.09% of MB was achieved at 40 min irradiation time, 0.01 g catalyst dose, 60 mg L-1 MB concentration and pH 9. The photocatalytic degradation of MB follows first order kinetic. RSM modeling of MB removal was also caried out. Reduce quadratic model was best fitted model having F-value = 300.65, P-value = < 0.0001,R2 = 0.9897, predicted R2 = 0.9850 and adjusted R2 = 0.9864.


Subject(s)
Oxides , Sunlight , Spectroscopy, Fourier Transform Infrared , Oxides/chemistry , Light , Catalysis , Methylene Blue/chemistry
8.
Chemosphere ; 328: 138476, 2023 Jul.
Article in English | MEDLINE | ID: mdl-36963573

ABSTRACT

The unplanned anthropogenic activities and raced industrial revolution detrimentally causes serious threat to terrestrial and aquatic life. A high discharge of wastewater from industries using dyes affects living organisms and the environment. This paper presents studies on polycationic selenides (PCS) synthesized by hydrothermal methods for photocatalytic degradation of dyes. The synthesized PCS were confirmed by various characterization techniques such as FTIR, SEM, EDX, UV/Vis, and XRD. The FTIR spectra revealed characteristic band at 843, 548 cm-1, and 417 cm-1 due to the M - Se stretching and intrinsic stretching vibrations, respectively. The optical bandgap of polycationic selenide lies in the visible light region (2.36 eV). The SEM images showed that PCS has a spherical shape with an average crystallite size of 29.23 nm calculated from XRD data using Scherer's equation. The PCS has a point of zero charge (PZC) at pH 7. The efficiency of synthesized PCS photocatalyst was confirmed in terms of its activity towards Eosin (EY) and Crystal violet (CV) dyes mineralization. The photocatalytic degradation for EY and CV dyes at optimum conditions was 99.47% and 99.31% and followed second order reactions kinetics with 1.4314 and 0.551 rate constant, respectively. The polynomial quadratic model is the best-fitted response surface methodology (RSM) model having a maximum desirability factors value and significant terms, with R2 (0.9994) and adj R2 values (1.0).


Subject(s)
Sunlight , Water Purification , Wastewater , Coloring Agents/chemistry , Textiles , Catalysis
9.
Environ Sci Pollut Res Int ; 30(16): 47077-47089, 2023 Apr.
Article in English | MEDLINE | ID: mdl-36735126

ABSTRACT

Mercury emissions from the industrial sector have become an undeniable concern for researchers due to their toxic health effects. Efforts have been made to develop green, efficient, and reliable methods for removal of mercury from wastewater. Sorption process promises fruitful results for the decontamination of cations from wastewater. Among the number of used sorbents, metal sulfides have been emerged as an appropriate material for removing toxic metals that possess good affinity due to sulfur-based active sites for Hg through "Lewis's acid-based soft-soft interactions." Herein, nickel-sulfide nanoparticles were synthesized, followed by their incorporation in chitosan microspheres. FTIR analysis confirmed the synthesis of nickel sulfide-chitosan microspheres (NiS-CMs) displaying sharp bands for multiple functional groups. XRD analysis showed that the NiS-CMs possessed a crystallite size of 42.1 nm. SEM analysis indicated the size of NiS-CMs to be 950.71 µm based on SEM micrographs. The sorption of mercury was performed using the NiS-CMs, and the results were satisfactory, with a sorption capacity of 61 mg/g at the optimized conditions of pH 5.0, 80 ppm concentration, in 60 min at 25 °C. Isothermal models and kinetics studies revealed that the process followed pseudo-second-order kinetics and the Langmuir isothermal model best fitted to experimental data. It was concluded that the NiS-CMs have emerged as the best choice for removing toxic mercury ions with a positive impact on the environment.


Subject(s)
Chitosan , Mercury , Water Pollutants, Chemical , Mercury/analysis , Chitosan/chemistry , Nickel/analysis , Microspheres , Wastewater , Decontamination , Cations/analysis , Hazardous Substances/analysis , Adsorption , Kinetics , Hydrogen-Ion Concentration , Water Pollutants, Chemical/analysis
10.
Int J Biol Macromol ; 235: 123591, 2023 Apr 30.
Article in English | MEDLINE | ID: mdl-36801223

ABSTRACT

Due to the rapid race of industrialization natural assets like fresh water has been deteriorated causing lethal effects in living organisms. In the current study robust and sustainable composite of in-situ antimony nanoarchitectonics in chitosan/synthesized carboxymethyl chitosan matrix were synthesized. To improve solubility, metal adsorption and water decontamination, chitosan was modified into carboxymethyl chitosan and the modification was confirmed through various characterization techniques. The characteristic bands in the FTIR spectrum confirm substitution of carboxymethyl group in the chitosan. This was further illustrated that the characteristic proton peaks of CMCh observed at δ = 4.097 to 4.192 ppm, suggesting O-carboxy methylation of chitosan by 1H NMR. The second order derivative of potentiometric analysis confirmed 0.83 degree of substitution. The antimony (Sb) loaded modified chitosan were confirmed by FTIR and XRD analysis. The potential effectiveness of chitosan matrix was determined and compared toward reductive removal of the Rhodamine b dye. Rhodamine b mitigation is following first order kinetics with R2 value of 0.9832 and 0.969 with a constant rate of 0.0977 and 0.2534 ml/min for Sb loaded chitosan and carboxymethyl chitosan respectively. The Sb/CMCh-CFP enables us to achieve 98.5 % mitigation efficiency within 10 min. The CMCh-CFP chelating substrate was found stable and efficient even after 4th batches of cycles with <4 % decrease in efficiency. The in-situ synthesized material was found tailored composite, in terms of dyes remediation, reusability and biocompatibility as compared to chitosan.


Subject(s)
Chitosan , Environmental Restoration and Remediation , Chitosan/chemistry , Antimony , Solubility , Copper/chemistry , Protons , Adsorption
11.
Chemosphere ; 313: 137483, 2023 Feb.
Article in English | MEDLINE | ID: mdl-36513201

ABSTRACT

Nanostructured materials offer a significant role in wastewater treatment with diminished capital and operational expense, low dose, and pollutant selectivity. Specifically, the nanocomposites of cellulose with inorganic nanoparticles (NPs) have drawn a prodigious interest because of the extraordinary cellulose properties, high specific surface area, and pollutant selectivity of NPs. Integrating inorganic NPs with cellulose biopolymers for wastewater treatment is a promising advantage for inorganic NPs, such as colloidal stability, agglomeration prevention, and easy isolation of magnetic material after use. This article presents a comprehensive overview of water treatment approaches following wastewater remediation by green and environmentally friendly cellulose/inorganic nanoparticles-based bio-nanocomposites. The functionalization of cellulose, functionalization mechanism, and engineered hybrid materials were thoroughly discussed. Moreover, we also highlighted the purification of wastewater through the composites of cellulose/inorganic nanoparticles via adsorption, photocatalytic and antibacterial approach.


Subject(s)
Environmental Pollutants , Nanocomposites , Nanoparticles , Water Pollutants, Chemical , Water Purification , Wastewater , Cellulose
12.
Int J Mol Sci ; 23(21)2022 Oct 22.
Article in English | MEDLINE | ID: mdl-36361538

ABSTRACT

In the present study KrF Excimer laser has been employed to irradiate the Cadmium (Cd) targets for various number of laser pulses of 500, 1000, 1500 and 2000, at constant fluence of 3.6 J cm-2. Scanning Electron Microscopy (SEM) analysis was utilized to reveal the formation of laser induced nano/micro structures on the irradiated target (Cd) surfaces. SEM results show the generation of cavities, cracks, micro/nano wires/rods, wrinkles along with re-deposited particles during irradiation in air, whereas subsurface boiling, pores, cavities and Laser Induced Periodic Surface Structures (LIPSS) on the inner walls of cavities are revealed at the central ablated area after irradiation in propanol. The ablated volume and depth of ablated region on irradiated Cd targets are evaluated for various number of pulses and is higher in air as compared to propanol ambient. Fast Fourier Transform Infrared spectroscopy (FTIR), Energy Dispersive X-ray Spectroscopy (EDS) and X-ray Diffraction (XRD) analyses show the presence of oxides and hydro-oxides of Cd after irradiation in propanol, whereas the existence of oxides is observed after irradiation in air ambient. Nano-hardness tester was used to investigate mechanical modifications of ablated Cd. It reveals an increase in hardness after irradiation which is more pronounced in propanol as compared to air.


Subject(s)
1-Propanol , Cadmium , Lasers , Microscopy, Electron, Scanning , Oxides
14.
Environ Res ; 215(Pt 3): 113978, 2022 12.
Article in English | MEDLINE | ID: mdl-35985490

ABSTRACT

The existence of heavy metals in ecological systems poses great threats to living organisms due to their toxicant and bio-accumulating properties. Mercury is a known toxicant with notable malignant impacts. It has long been known to cause toxic threats to the health of living organisms since the break out of Minamata disease. The turbulent expulsion of mercury-based pollutants from the industrial sector, requires a proper solution. Many attempts have been made to design a greener and more efficient route for a satisfactory removal of mercury. In the current study, bismuth sulfide nanoparticles (BiSNPs) have been synthesized via the co-precipitation method. The BiSNPs were supported with crosslinked chitosan to enhance their sorption capacity and avoid leaching. The average size of the BiSNPs was 42 nm based on SEM micrographs. The SEM analysis of the bismuth sulfide chitosan-crosslinked beads (BiS-CB) showed that the beads possessed a spherical and smooth morphology with a size of 1.02 mm. The FTIR analysis showed that the beads possessed the characteristics bands of imine groups of chitosan, bismuth, sulfur, and glycosidic linkages present in the molecules. The XRD analysis confirmed the phase crystallinity of the BiS-CB with an average crystallite size of 11 nm. The BiS-CB was employed for the sorption of mercury from water samples. The maximum sorption capacity of 65.51 mg/g was achieved at optimized conditions of pH 5, concentration 80 ppm, in 45 min at 30 °C. The mechanism studied for mercury removal showed that sorption followed the complexation mechanism according to the SHAB concept. In conclusion, the results showed that the BiS-CB sorbent exhibited an excellent sorption capacity to remove mercury.


Subject(s)
Chitosan , Environmental Pollutants , Mercury , Metals, Heavy , Nanoparticles , Water Pollutants, Chemical , Adsorption , Bismuth , Chitosan/chemistry , Hydrogen-Ion Concentration , Imines , Kinetics , Mercury/chemistry , Rivers , Sulfides , Sulfur , Water/chemistry , Water Pollutants, Chemical/chemistry
15.
Environ Res ; 215(Pt 2): 114148, 2022 12.
Article in English | MEDLINE | ID: mdl-35995231

ABSTRACT

Three different types (blank, annealed, and functionalized) of copper ferrite nanoparticles (CuFe2O4) were synthesized by the co-precipitation method. The CuFe2O4 NPs were characterized by Fourier transform infrared (FTIR), Scanning electron microscopy (SEM), X-ray diffraction (XRD), and Energy-dispersive X-ray spectroscopy (EDX) techniques. FTIR analysis confirmed that 3-APTES is successfully grafted on the surface of CuFe2O4 NPs. XRD results show the amorphous nature of blank CuFe2O4 NPs, and crystalline structure was observed for annealed and functionalized CuFe2O4 NPs. XRD results revealed that crystallite size ranges from 23.6 to 34.6 nm. SEM micrographs of blank CuFe2O4 NPs show the irregular shape and size of the nanostructure. The spherical and strongly linked structure was seen in the micrograph of functionalized CuFe2O4 NPs. EDX analysis revealed the nanostructure composed of Fe, Cu, O, and a small percentage of Si. The photocatalytic degradation efficiency of synthesized CuFe2O4 NPs was examined under UV irradiation in an aqueous medium against bromophenol blue (BPB) dye. The effect of different parameters such as irradiation time and pH on the photodegradation of BPB dye was studied by all three types of CuFe2O4 photocatalyst. Results show that the maximum photocatalytic degradation efficiency was observed for functionalized CuFe2O4 nanoparticles that degraded 98% of BPB dye in the acidic medium at pH = 1. The optimum contact time for dye degradation was 120 min by synthesized photocatalyst. Photodegradation performance of blank and annealed CuFe2O4 NPs is less than 90%. The synthesized CuFe2O4 NPs were recycled and reused, which shows good photocatalytic degradation efficiency up to 4 consecutive cycles. The kinetic model displayed that degradation reaction followed pseudo 1st order kinetics. The blank, annealed, and functionalized CuFe2O4 NPs have turnover numbers of 10.7x10 (Mudhoo et al., 2019), 12.9x10 (Mudhoo et al., 2019), and 22.2x10 (Mudhoo et al., 2019) (kg-1 sec-1) accordingly. In conclusion, all results revealed the high efficiency of prepared photocatalyst for tested hazardous dye from wastewater and encouraged more work on photodegradation of organic pollutants from wastewater.


Subject(s)
Environmental Pollutants , Nanostructures , Bromphenol Blue , Catalysis , Copper/chemistry , Ferric Compounds , Polyethylene Glycols , Porosity , Wastewater
16.
Antibiotics (Basel) ; 11(8)2022 Aug 04.
Article in English | MEDLINE | ID: mdl-36009926

ABSTRACT

Actinomycetes, most notably the genus Streptomyces, have great importance due to their role in the discovery of new natural products, especially for finding antimicrobial secondary metabolites that are useful in the medicinal science and biotechnology industries. In the current study, a genome-based evaluation of Streptomyces sp. isolate BR123 was analyzed to determine its biosynthetic potential, based on its in vitro antimicrobial activity against a broad range of microbial pathogens, including gram-positive and gram-negative bacteria and fungi. A draft genome sequence of 8.15 Mb of Streptomyces sp. isolate BR123 was attained, containing a GC content of 72.63% and 8103 protein coding genes. Many antimicrobial, antiparasitic, and anticancerous compounds were detected by the presence of multiple biosynthetic gene clusters, which was predicted by in silico analysis. A novel metabolite with a molecular mass of 1271.7773 in positive ion mode was detected through a high-performance liquid chromatography linked with mass spectrometry (HPLC-MS) analysis. In addition, another compound, meridamycin, was also identified through a HPLC-MS analysis. The current study reveals the biosynthetic potential of Streptomyces sp. isolate BR123, with respect to the synthesis of bioactive secondary metabolites through genomic and spectrometric analysis. Moreover, the comparative genome study compared the isolate BR123 with other Streptomyces strains, which may expand the knowledge concerning the mechanism involved in novel antimicrobial metabolite synthesis.

17.
Top Curr Chem (Cham) ; 380(5): 44, 2022 Aug 11.
Article in English | MEDLINE | ID: mdl-35951126

ABSTRACT

Nanotechnology has emerged as an extraordinary and rapidly developing discipline of science. It has remolded the fate of the whole world by providing diverse horizons in different fields. Nanomaterials are appealing because of their incredibly small size and large surface area. Apart from the naturally occurring nanomaterials, synthetic nanomaterials are being prepared on large scales with different sizes and properties. Such nanomaterials are being utilized as an innovative and green approach in multiple fields. To expand the applications and enhance the properties of the nanomaterials, their functionalization and engineering are being performed on a massive scale. The functionalization helps to add to the existing useful properties of the nanomaterials, hence broadening the scope of their utilization. A large class of covalent and non-covalent functionalized nanomaterials (FNMs) including carbons, metal oxides, quantum dots, and composites of these materials with other organic or inorganic materials are being synthesized and used for environmental remediation applications including wastewater treatment. This review summarizes recent advances in the synthesis, reporting techniques, and applications of FNMs in adsorptive and photocatalytic removal of pollutants from wastewater. Future prospects are also examined, along with suggestions for attaining massive benefits in the areas of FNMs.


Subject(s)
Environmental Restoration and Remediation , Nanostructures , Water Purification , Nanotechnology/methods , Wastewater , Water Purification/methods
18.
Antibiotics (Basel) ; 11(7)2022 Jul 05.
Article in English | MEDLINE | ID: mdl-35884151

ABSTRACT

Analytical methods for the drug substance and degradation products (DPs) are validated by performing forced degradation studies. Forced degradation studies of Velpatasvir (VEL) drug substance and Velpatasvir copovidone solid dispersion (VEL-CSD) were performed under the stressed alkaline, acidic, oxidative and thermal conditions according to ICH guidelines ICH Q1A (R2). VEL is labile to degrade in stressed alkaline, acidic, and oxidative conditions. It is also photolabile and degraded during photostability studies as described by ICH Q1B, and showed no degradation on exposure to extreme temperature when protected from light. A sensitive stability indicating HPLC-UV method was developed and validated for the separation of VEL and eight DPs. The DPs of VEL are separated using gradient elution of mobile phase containing 0.05% Trifluoroacetic acid (TFA) and methanol over symmetry analytical column C18 (250 mm × 4.6 mm, 5 µm) with a flow rate of 0.8 mL min-1. Simultaneous detection of all DPs and VEL was performed on UV detector at 305 nm. The performance parameters like precision, specificity and linearity of the method were validated using reference standards as prescribed by ICHQ2 (R1). Limits of quantification and limits of detection were determined from calibration curve using the expression 10δ/slope and 3δ/slope respectively. The proposed method is stability-indicating and effectively applied to the analysis of process impurities and DPs in VEL drug substance and VEL-CSD.

19.
Environ Sci Pollut Res Int ; 29(57): 86606-86615, 2022 Dec.
Article in English | MEDLINE | ID: mdl-35799009

ABSTRACT

The problem of disposing and managing solid waste materials has become one of the major environmental, economic, and social issues. Utilization of solid wastes in the production of building materials not only solves the problem of their disposal but also helps in the conversion of wastes into useful and cost-effective products. In the present study, solid waste materials of organic and inorganic nature were applied in the production of sustainable cementitious composites (CC) and studied the effect of incorporated wastes on physical and mechanical properties of the resultant CC. The selected solid waste materials were cotton, polyester, PET, carpet, glass, and granulated blast furnace slag (GBFS). These wastes were incorporated in CC in different proportions and form the tuff tiles using moulds (12.5″ × 6″ × 2.5″). The various physical (fineness, setting time, bulk density, and water absorption capacity) and mechanical (flexural strength) properties of all the specimens were determined after curing period of 3, 7, and 28 days. The results show that the incorporation of solid wastes in CC did not much affect their physical characteristics. However, the CC incorporated with the selected solid waste materials have a pronounced effect of their flexural strength and found to be higher (12-875%) compared to the plain CC. Similarly, the incorporation of the selected inorganic wastes (302-715 psi) in CC exhibit much higher flexural strength compared to the organic wastes (136-235 psi). The maximum flexural strength was observed when GBFS was utilized as a solid waste. The present work will provide a reliable step for the solid waste management and conversion of such wastes into useful commercial products for concrete manufacturing.


Subject(s)
Refuse Disposal , Waste Management , Solid Waste , Refuse Disposal/methods , Construction Materials , Waste Management/methods , Glass
20.
J Environ Manage ; 319: 115690, 2022 Oct 01.
Article in English | MEDLINE | ID: mdl-35834853

ABSTRACT

Due to the environmental and production problems of emulsion, it is important to efficiently separate oil-water emulsion to meet the refinery requirement and clean up oil spills. Synthesis of a universal demulsifier is not an easy task because the physical properties of crude oil vary, which makes its characterization and demulsification procedure difficult. To overcome this problem, hydrophilic and magnetically recoverable poly (methyl methacrylate-acrylic acid)/iron oxide magnetic composite nanoparticles ((P(MMA-AA)/Fe3O4 NPs) were developed as an efficient and economical demulsifier via soap-free emulsion polymerization. To characterize the magnetic composite NPs for their appropriate surface morphology and magnetic domain, TEM, FTIR, VSM, and TGA analyses were carried out. The newly synthesized NPs displayed good hydrophilic properties as they migrated quickly to the aqueous emulsion phase, which was also reassured by their water contact angle of 75°. They exhibit strong magnetic characteristics (20 amu/g) in the oil-water emulsion, makings the hydrophilic wettability capable and attractive to the external magnet. Experimental results revealed that the prepared magnetic composite NPs separated 99% of the water from stable emulsion in 30 min and could be recycled 8 times through magnetic separation. The recycled magnetic composite NPs maintain their hydrophilic wettability and efficiency in separating oil-water emulsion, making them economical and commercially viable. The migration of magnetic composite NPs to the aqueous phase in the stable emulsion with a strong magnetic domain explains the coalescence of emulsified water droplets and their quick separation from the stable emulsions through the external magnet.


Subject(s)
Nanostructures , Water , Acrylates , Emulsions , Ferric Compounds , Magnetic Phenomena , Methacrylates , Methylmethacrylate , Oils , Wettability
SELECTION OF CITATIONS
SEARCH DETAIL
...