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1.
Photochem Photobiol Sci ; 23(8): 1533-1542, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-39030314

RESUMEN

Removal of organic dyes like methylene blue (MB) from industrial effluents serves as potential source of potable water. Photocatalytic degradation using sustainable catalyst is deemed to be an affordable solution. In this work, Nd2O3/MgO nanocomposite with different compositions (1, 3, and 5wt% Nd2O3 with MgO) have been achieved using hydrothermal synthesis and characterized extensively. Interestingly, increasing Nd2O3 proportion (1-5%) enhances light absorption, and decreases band gap and electron-hole recombination. The efficacy of the photocatalysts is tested with the degradation of MB dye, through optimizing Nd2O3/MgO proportion, contact time, catalyst dose, and pH. Interestingly, control experiments reveal that 5wt% Nd2O3/MgO achieve 99.6% degradation of MB in 90 min at pH 7, compared to 88.8% with bare MgO under same condition. Kinetic data show that 5wt% Nd2O3/MgO exhibits ca. 3 times higher degradation rate compared to MgO. For the first time, our work enable MgO-based sustainable photocatalyst development with minimum (5 wt%) rare-earth combination to achieve excellent photocatalytic degradation performance.

2.
Environ Res ; 219: 115140, 2023 02 15.
Artículo en Inglés | MEDLINE | ID: mdl-36565846

RESUMEN

Abuse of carbendazim (CBZ) leaves excessive pesticide residues on agricultural products, which endangers human health because of the residues' high concentrations. Hence, a composite consisting of functionalized carbon nanofibers (f-CNF) with neodymium oxide (Nd2O3) was fabricated to monitor CBZ at trace levels. The Nd2O3/f-CNF composite-modified electrode displays higher electro-oxidation ability towards CBZ than Nd2O3 and f-CNF-modified electrodes. The combined unique properties of Nd2O3 and f-CNF result in a substantial specific surface area, superior structural stability, and excellent electrocatalytic activity of the composite yielding enhanced sensitivity to detecting CBZ with a detection limit of 4.3 nM. Also, the fabricated sensor electrode can detect CBZ in the linear concentration range of up to 243.0 µM with high selectivity, appropriate reproducibility, and stability. A demonstration of the sensing capability of CBZ in vegetables, water, and soil samples was reported paving the way for its use in practical applications.


Asunto(s)
Fungicidas Industriales , Nanofibras , Humanos , Carbono/química , Verduras , Agua , Reproducibilidad de los Resultados , Suelo
3.
Zhonghua Lao Dong Wei Sheng Zhi Ye Bing Za Zhi ; 40(12): 881-887, 2022 Dec 20.
Artículo en Zh | MEDLINE | ID: mdl-36646477

RESUMEN

Objective: To explore the effects of Nd(2)O(3) exposure to rare earth particles on the secretion of sex hormones, cytochrome P450 family member 11A1 (CYP11A1) , spermatogenesis markers promyelocytic leukemia zinc finger protein (PLZF) and retinoic acid stimulating gene 8 (STRA8) protein in C57 BL/6J male mice. Methods: In March 2021, Forty-eight male C57 BL/6J mice aged 6-8 weeks divided into control group and Nd(2)O(3) exposure low, medium and high dose groups (exposing doses of 62.5, 125.0, 250.0 mg/ml Nd(2)O(3)) , 12 per group. The mice in the Nd(2)O(3) groups were perfused with different doses of Nd(2)O(3) suspension by a one-time non-exposing tracheal instillation method, and the control group was perfused with an equal volume of normal saline, with a volume of 0.1 ml, to establish a mouse reproductive function injury model. After 28 days of exposure, the mice's body weight, testes and epididymis were weighed, and the organ coefficients were calculated; the two epididymis were taken to make a sperm suspension to determine the sperm count, survival rate, and deformity rate; inductively coupled plasma mass spectrometry (ICP-MS) method was used to detect the content of Nd in mouse testis tissue; HE staining was used to detect testicular tissue pathological changes and quantitative analysis; enzyme-linked immunosorbent assay (ELISA) method was used to detect serum luteinizing hormone (LH) and follicle stimulating hormone (FSH) and testosterone (T) content; western blot was used to detect the protein levels of CYP11A1, PLZF and STRA8 in testicular tissues. Results: Compared with the control group, with the increase of the exposure dose, the Nd content in the testis of the mice showed an increasing trend, the sperm survival rate and LH showed a decreasing trend, and the sperm deformity rate showed an increasing trend (P<0.05) ; Pathological showed that the number of sperm in the seminiferous tubules of the testicular tissue in the Nd(2)O(3) medium and high dose groups was significantly reduced, and the germinal epithelial disintegration, intraepithelial vacuolization, and exfoliation of spermatogenic cells and supporting cells occurred; The height of germinal epithelium was significantly reduced, and the percentage of damaged seminiferous tubules showed an increasing trend (P<0.05) ; FSH and T levels in serum in the middle and high dose groups of Nd(2)O(3), and CYP11A1, PLZF and STRA8 proteins in testicular tissues showed a downward trend with increasing dose (P<0.05) . Conclusion: The rare earth particulate Nd(2)O(3) may interfere with the expression of CYP11A1, PLZF and STRA8 protein, thereby causing the disorder of sex hormone secretion in the body, the maintenance of spermatogonia and the obstruction of the process of meiosis, causing reproductive function damage.


Asunto(s)
Enzima de Desdoblamiento de la Cadena Lateral del Colesterol , Neodimio , Semen , Animales , Masculino , Ratones , Proteínas Adaptadoras Transductoras de Señales/metabolismo , Enzima de Desdoblamiento de la Cadena Lateral del Colesterol/metabolismo , Hormona Folículo Estimulante/metabolismo , Hormona Luteinizante/metabolismo , Proteína de la Leucemia Promielocítica con Dedos de Zinc/metabolismo , Semen/metabolismo , Recuento de Espermatozoides , Espermatogénesis , Testículo , Testosterona/metabolismo , Neodimio/toxicidad , Óxidos/toxicidad
4.
Heliyon ; 10(9): e29894, 2024 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-38707437

RESUMEN

To improve the photocatalytic property of TiO2 thin films, the composite thin films of TiO2/Nd2O3 structure were fabricated by electron-beam physical vapor deposition method, and the photocatalytic property of the fabricated films was experimentally studied in the present work. The XRD and Raman analyses show that the TiO2/Nd2O3 films are mainly hexagonal crystalline phase of Nd2O3. The XPS analysis for the chemical state changes of Ti, O and Nd of the basic elements in the films is confirming the electron flow in the internal electric field which generated in the TiO2/Nd2O3 films. The surface morphology shows the lattice distortion which affects the changes in the energy band structure. Moreover, the formation of n-n homojunctions improved the separation efficiency of electrons and holes, and enhanced the catalytic activity. The photocatalytic performance for the methylene blue target dye shows that the sample with TiO2 thickness of 20-25 nm has better performance, high degradation efficiency and high reaction rate.

5.
Gels ; 10(7)2024 Jul 17.
Artículo en Inglés | MEDLINE | ID: mdl-39057491

RESUMEN

In this research, the influence of the thermal treatment of geopolymer gels at 300 °C, 600 °C and 900 °C when incorporated with 5% rare earth elements (REEs) in the form of (GP-Sm) Sm2O3 and (GP-Nd) Nd2O3 was investigated. Changes in the chemical and structural properties of the geopolymer gels during thermal treatment for 1 h were monitored. Physico-chemical characterization was performed using the following methods: diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS), scanning electron microscopy with energy dispersive spectrometry (SEM-EDS), and X-ray photoelectron spectroscopy (XPS). Besides the characterization of the fundamental properties, some practical macroscopic properties were analyzed as well: sorptivity, open porosity, and Archimedean density. The stretching vibrations of Nd-O-Si and Sm-O-Si were confirmed at a value of around 680 cm-1and an Nd-O-Si absorption band at a higher value, together with the most dominant band of Si-O stretching vibration similar for all the samples. No significant chemical changes occurred. Structural analysis showed that for GP-Nd, the largest pore diameter was obtained at 900 °C, while for GP-Sm, the largest pore diameter was obtained at 600 °C. EDS confirmed the amount of dopant to be about 5%. X-ray photoelectron spectroscopy showed that for GP-Nd, the ratio of Si and Al changed the most, while for GP-Sm, the ratio of Si and Al decreased with increasing temperature. The contributions of both dopants in the GP-gel structure remained almost unchanged and stable at high temperatures. The atomic percentages obtained by XPS analysis were in accordance with the expected trend; the amount of Si increased with the temperature, while the amount of Al decreased with increasing temperature. The sorptivity and open porosity showed the highest values at 600 °C, while the density of both geopolymers decreased linearly with increasing temperature.

6.
Environ Pollut ; 358: 124527, 2024 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-38992831

RESUMEN

Neodymium oxide (Nd2O3) is a rare earth element that can lead to various type of tissue and organ damage with prolonged exposure. The long noncoding RNA small nucleolar ribonucleic acid host gene 5 (lncRNA SNHG5) plays a role in disease progressiong. However, its connection with Nd2O3 induced reproductive harm in males has not been thoroughly investigated. Our research discovered that exposure to Nd2O3 increases the expression of SNHG5 in the testes of mice, which in turn binds directly to and reduces in the protein levels of insulin like growth factor 2 mRNA-binding protein 1 (IGF2BP1) both in vivo and in vitro. This process disrupts the cytoskeleton of blood-testis barrier(BTB) by impacting the stability of the tight junction protein Occludin (Ocln) mRNA structure and the permeability of the BTB. In summary, our study elucidates the regulatory mechanism of SNHG5/IGF2BP1/Occludin axis in Nd2O3-induced BTB injury, providing valuable insights for the treatment of male infertility.


Asunto(s)
Barrera Hematotesticular , Ocludina , ARN Largo no Codificante , Animales , Masculino , Ratones , Barrera Hematotesticular/metabolismo , Ocludina/genética , Ocludina/metabolismo , ARN Largo no Codificante/genética , ARN Largo no Codificante/metabolismo , Proteínas de Unión al ARN/metabolismo , Proteínas de Unión al ARN/genética , Testículo/metabolismo
7.
Nanomaterials (Basel) ; 13(10)2023 May 18.
Artículo en Inglés | MEDLINE | ID: mdl-37242079

RESUMEN

The following investigation presents the thermal treatment of geopolymer at 300 °C, 600 °C and 900 °C. We investigated what happens to the geopolymer base when incorporated with 1% and 5% of neodymium in the form Nd2O3. A total of six samples were synthesized. Geopolymer 1 contained 1% and geopolymer 2 contained 5% Nd2O3, and these samples were treated at 300 °C; then, samples geopolymer 3 and geopolymer 4 also had the same percentage composition of Nd2O3 and were treated at 600 °C, while samples geopolymer 5 and geopolymer 6were treated at 900 °C. Physical and chemical changes in the aluminosilicate geopolymer matrix were monitored. The incorporation of rare earths into the polymer network of aluminosilicates has been proven to disrupt the basic structure of geopolymers; however, with increased temperatures, these materials show even more unusual properties. Diffuse reflectance infrared Fourier transform (DRIFT) analysis showed that the intensity of the vibrational band decreases with the increase in temperature during thermal treatment, suggesting alterations in the chemical structure of the geopolymers. Transmission electron microscopy (TEM) analysis showed that the diameter of the nanoparticles containing Al2O3 is in the range 5-10 nm, while larger crystallites range from 30 to 80 nm. Scanning electron microscopy (SEM) analysis revealed that the temperature of the thermal treatment increases to 300 °C and 600 °C; the porosity of geopolymer increases in the form of the appearance of large pores and cracks in material. X-ray photoelectron spectroscopy (XPS) analysis was used to investigate the surface chemistry of geopolymers, including the chemical composition of the surface, the oxidation state of the elements, and the presence of functional groups. The UV/Vis spectra of the synthesized geopolymers doped with Nd3+ show interesting optical properties at 900 °C; the geopolymer matrix completely disintegrates and an amorphous phase with a rare-earth precipitate appears.

8.
Materials (Basel) ; 16(4)2023 Feb 17.
Artículo en Inglés | MEDLINE | ID: mdl-36837323

RESUMEN

A 3D hierarchical spherical honeycomb-like composite electrode materialof neodymium oxide (Nd2O3), cobalt tetraoxide (Co3O4), and reduced graphene oxide (rGO) on nickel foam (named as Nd2O3/Co3O4/rGO/NF) were successfully fabricated by combining the hydrothermal synthesis method and the annealing process. Nickel foam with a three-dimensional spatial structure was used as the growth substrate without the use of any adhesives. The Nd2O3/Co3O4/rGO/NF composite has outstanding electrochemical performance and can be used directly as an electrode material for supercapacitors (SCs). By taking advantage of the large specific surface area of the electrode material, it effectively slows down the volume expansion of the active material caused by repeated charging and discharging processes, improves the electrode performance in terms of electrical conductivity, and significantly shortens the electron and ion transport paths. At a 1 A/g current density, the specific capacitance reaches a maximum value of 3359.6 F/g. A specific capacitance of 440.4 F/g with a current density of 0.5A/g is still possible from the built symmetric SCs. The capacitance retention rate is still 95.7% after 30,000 cycles of testing at a high current density of 10 A/g, and the energy density is 88.1 Wh/kg at a power density of 300 W/kg. The outcomes of the experiment demonstrate the significant potential and opportunity for this composite material to be used as an electrode material for SCs.

9.
Polymers (Basel) ; 15(20)2023 Oct 14.
Artículo en Inglés | MEDLINE | ID: mdl-37896328

RESUMEN

Polyvinyl alcohol (PVA) and Neodymium (III) oxide (Nd2O3) were combined to synthesized flexible innovative PVA/Nd2O3 polymer composite samples utilizing a solution casting approach for use in dielectric devices. The XRD, FTIR, and SEM methods are all investigated to characterize the composite films. In a frequency of 50 Hz to 5 MHz, the effects of additive Nd2O3 on the dielectric behavior of PVA were recorded. The PVA/Nd2O3 composite films were successfully fabricated, as shown by XRD and infrared spectroscopy. The scanning microscopy pictures showed that the Nd2O3 was loaded and distributed uniformly throughout the PVA. After the incorporation of Nd2O3, the composite PVA/Nd2O3 has a conductivity of 6.82 × 10-9 S·cm-1, while the PVA has a conductivity of 0.82 × 10-9 S·cm-1. Another improvement is the decrease in the relaxation time from 14.2 × 10-5 s for PVA to 6.35 × 10-5 s for PVA/Nd2O3, and an increase in the dielectric constant of 0.237 for PVA to 0.484 at a frequency of 100 Hz. The results showed that the composite samples have considerable changes as flexible films in different applications, including batteries and electronic circuits.

10.
Environ Sci Pollut Res Int ; 30(32): 78332-78338, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-37269512

RESUMEN

Nanoparticulate-Nd2O3 (nano-Nd2O3) has been excessively utilized in agriculture, industry, and medicine. Hence, nano-Nd2O3 can have environmental implications. However, the impact of nano-Nd2O3 on alpha diversity, composition, and function of soil bacterial communities has not been thoroughly evaluated. We amended soil to achieve different concentrations of nano-Nd2O3 (0, 10, 50, and 100 mg kg-1 soil) and incubated the mesocosms for 60 days. On days 7 and 60 of the experiment, we measured the effect of nano-Nd2O3 on alpha diversity and composition of soil bacterial community. Further, the effect of nano-Nd2O3 on the function of soil bacterial community was assessed based on changes in the activities of the six potential enzymes that mediate the cycling of nutrients in the soil. Nano-Nd2O3 did not alter the alpha diversity and composition of the soil bacterial community; however, it negatively affected community function in a dose-dependent manner. Specifically, the activities of ß-1,4-glucosidase and ß-1,4-n-acetylglucosaminidase that mediate soil carbon and nitrogen cycling, respectively, were significantly affected on days 7 and 60 of the exposure. The effect of nano-Nd2O3 on the soil enzymes correlated with changes in relative abundances of the rare and sensitive taxa, viz., Isosphaerales, Isosphaeraceae, Ktedonobacteraceae, and Streptomyces. Overall, we provide information for the safe implementation of technological applications that use nano-Nd2O3.


Asunto(s)
Chloroflexi , Suelo , Microbiología del Suelo , Agricultura , Bacterias
11.
Sci Total Environ ; 863: 160819, 2023 Mar 10.
Artículo en Inglés | MEDLINE | ID: mdl-36526188

RESUMEN

Neodymium oxide nanoparticles (NPs-Nd2O3) are increasingly being used in industry and biomedicine, causing adverse health effects such as lung disease. However, the underlying molecular mechanisms controlling these adverse consequences are unknown at present. In this study, a human bronchial epithelial cell line (16HBE) was exposed to increasing concentrations of NPs-Nd2O3, and Sprague-Dawley rats were treated with NPs-Nd2O3 by intratracheal instillation. We found that NPs-Nd2O3 exposure induced DNA damage and down-regulated levels of circular RNA (circRNA) circ_002363 in 16HBE cells as well as in rat lung tissue. We also observed that circ_002363 levels in the serum of workers employed in the production of NPs-Nd2O3 diminished as the work time progressed, suggesting that circ_002363 may be a potential biomarker of lung injury. Functional experiments showed that circ_002363 significantly inhibited DNA damage induced by NPs-Nd2O3. RNA pull-down and western blot assays found that circ_002363 interacted with proteins PARP1/Ku70/Ku80/Rad50, which are critical participants in non-homologous end-joining (NHEJ) DNA repair. Moreover, we found that formation of circ_002363 was regulated by the RNA binding protein Breast Carcinoma Amplified Sequence 2 (BCAS2). The BCAS2 protein affected circ_002363 expression through interaction with Pre-DNA2, the host gene of circ_002363, in NPs-Nd2O3-exposed 16HBE cells. In conclusion, our findings show first that circ_002363, which is regulated by BCAS2, acts as regulator of DNA damage via the NHEJ pathway. These results enhance our understanding of the regulatory mechanisms controlling the actions of circular RNAs and highlight the relationship between genetics and epigenetics in the development of diseases following exposure to environmental chemicals.


Asunto(s)
MicroARNs , Nanopartículas , Humanos , Animales , Ratas , Ratas Sprague-Dawley , Reparación del ADN por Unión de Extremidades , Daño del ADN , Nanopartículas/toxicidad , ARN Circular/metabolismo , MicroARNs/metabolismo , Proteínas de Neoplasias/genética
12.
Toxicol Sci ; 197(1): 27-37, 2023 12 21.
Artículo en Inglés | MEDLINE | ID: mdl-37831906

RESUMEN

Some rare earth elements are occupational and environmental toxicants and can cause organ and systemic damage; therefore, they have attracted global attention. Neodymium oxide (Nd2O3) is a rare earth element that is refined and significantly utilized in China. The long noncoding RNA (lncRNA) H19 is encoded by the H19/IGF2 imprinted gene cluster located on human chromosome 11p15.5. H19 has become a research focus due to its ectopic expression leading to the promotion of fibrosis. However, the mechanisms by which it causes pulmonary fibrosis are elusive. This investigation indicates that biologically active Nd2O3 increases H19, SNIP1, and c-myc, decreases miR-29a-3p, accelerates macrophage M2 polarization, and causes pulmonary fibrosis in mice lung tissues. In macrophage-differentiated THP-1 cells, Nd2O3 (25 µg/ml) enhanced H19, SNIP1, and c-myc, reduced miR-29a-3p, accelerated macrophages M2 polarization, and stimulated fibrogenic cytokine (TGF-ß1) secretion. Furthermore, the coculturing of Nd2O3-treated macrophage-differentiated THP-1 cells. And human embryonic lung fibroblast cells activated lung fibroblast, which increases the levels of collagen I, α-SMA, p-Smad2/3, and Smad4, whereas H19 knockdown or miR-29a-3p upregulation in macrophages had opposite effects. Moreover, it was revealed that H19/miR-29a-3p/SNIP1/c-myc regulatory axis is involved in pulmonary fibrosis induced by Nd2O3. Therefore, this study provides new molecular insights into the mechanism of pulmonary fibrosis by Nd2O3.


Asunto(s)
MicroARNs , Fibrosis Pulmonar , ARN Largo no Codificante , Humanos , Animales , Ratones , MicroARNs/genética , MicroARNs/metabolismo , ARN Largo no Codificante/genética , ARN Largo no Codificante/metabolismo , Fibrosis Pulmonar/inducido químicamente , Fibrosis Pulmonar/genética , Óxidos , Proteínas de Unión al ARN
13.
Environ Pollut ; 334: 122191, 2023 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-37451587

RESUMEN

The widespread use of neodymium oxide nanoparticles (NPs-Nd2O3) has caused environmental pollution and human health problems, thus attracting significant attention. Understanding the mechanisms of NPs- Nd2O3-induced genetic damage is of great significance for identifying early markers for NPs- Nd2O3-induced lung injury. At present, the mechanisms underlying DNA damage induced by NPs- Nd2O3 remain unclear. In this study, we performed functional assays on human bronchial epithelial cells (16HBEs) exposed to various concentrations of NPs-Nd2O3 and SD rats administered with a single intratracheal instillation with NPs-Nd2O3. Exposure to NPs-Nd2O3 could lead to DNA damage in 16HBE cells and rat lung tissue cells. We found a novel long non-coding RNA, named CNTFR-AS1, which was highly expressed after exposure to NPs-Nd2O3. Our data verified that transcription factor TP63 mediates the high expression levels of CNTFR-AS1, which in turn regulates NPs-Nd2O3-induced DNA damage in cells by inhibiting HR repair. Moreover, the levels of CNTFR-AS1 were correlated with the number of years worked by occupational workers. Collectively, these results demonstrate that CNTFR-AS1 acts as a novel DNA damage regulator in bronchial epithelial cells exposed to NPs-Nd2O3. Hence, our data provide a basis for the identification of lncRNAs as early diagnostic markers for rare earth lung injury.


Asunto(s)
Lesión Pulmonar , Nanopartículas , ARN Largo no Codificante , Humanos , Animales , Ratas , ARN Largo no Codificante/genética , Factores de Transcripción , Reparación del ADN por Recombinación , Ratas Sprague-Dawley , Daño del ADN , Proteínas Supresoras de Tumor , Subunidad alfa del Receptor del Factor Neurotrófico Ciliar
14.
Toxicol In Vitro ; 78: 105271, 2022 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-34740776

RESUMEN

The health hazards of nanoparticles of neodymium oxide (NPs-Nd2O3) have aroused public concern in recent years. Exposure to NPs-Nd2O3 can change the level of reactive oxygen species (ROS) that cause DNA damage and alter whole transcriptome expression profiles for micro (mi)RNA, circular (circ)RNA, long noncoding (lnc)RNA, and mRNA. However, there have been no reports to our knowledge about the role of circRNAs in DNA damage caused by NPs-Nd2O3. In our study, we analyzed the circRNA expression profile of human bronchial epithelial cells(16HBE)exposed to 40 µg/ml NPs-Nd2O3. Our results indicated that exposure produced 1025 up-regulated and 890 down-regulated circRNAs. Real-time quantitative polymerase chain reaction (qRT-PCR) was applied to verify some of the significantly changed circRNAs and demonstrated that circ_009773 was apparently down-regulated. Through exploration of its host gene function, we found that circ_009773 may be related to DNA damage. Functional experiments found that circ_009773 regulated NPs-Nd2O3-induced DNA damage in 16HBE cells. A circ_009773-associated competing endogenous (ce)RNA network was constructed based on one differentially expressed (DE) circRNA, 74 DE miRNAs and 208 DE mRNAs. Module analysis identified hub genes related to DNA damage and repair and a protein-protein interaction (PPI) network was created.


Asunto(s)
Daño del ADN/genética , Nanopartículas/toxicidad , Neodimio/toxicidad , Óxidos/toxicidad , ARN Circular/metabolismo , Bronquios/efectos de los fármacos , Línea Celular , Células Epiteliales/efectos de los fármacos , Perfilación de la Expresión Génica , Redes Reguladoras de Genes , Humanos , ARN Circular/genética , Análisis de Secuencia de ARN
15.
Nanomaterials (Basel) ; 12(7)2022 Mar 24.
Artículo en Inglés | MEDLINE | ID: mdl-35407178

RESUMEN

The growth of the textile industry results in a massive accumulation of dyes on water. This enormous rise in pigments is the primary source of water pollution, affecting the aquatic lives and our ecosystem balance. This study aims to notify the fabrication of neodymium incorporated copper oxide (Nd2O3 doped CuO) nanoparticles by combustion method for effective degradation of dye, methylene blue (MB). X-ray diffraction (XRD), Field emission Scanning electron microscopy (FESEM), Zeta potential have been applied for characterization. Photocatalyst validity has been evaluated for methylene blue degradation (MB). Test conditions such as time of contact, H2O2, pH, and photo-Fenton have been modified to identify optimal degradation conditions. Noticeably, 7.5% Nd2O3 doped CuO nanoparticle demonstrated the highest photocatalytic efficiency, up to 90.8% in 80 min, with a 0.0227 min-1 degradation rate. However, the photocatalytic efficiency at pH 10 becomes 99% with a rate constant of 0.082 min-1. Cyclic experiments showed the Nd2O3 doped CuO nanoparticle's stability over repeated use. Scavenge hydroxyl radical species responsible for degradation using 7.5% Nd2O3 doped CuO nanoparticles have been investigated under visible irradiation.

16.
Gels ; 7(4)2021 Nov 03.
Artículo en Inglés | MEDLINE | ID: mdl-34842670

RESUMEN

The present work was focused on doping of 1% and 5% both of Nd2O3 and Sm2O3 in geopolymer gels. One of the main goals was to determine the influence of the behavior of Nd and Sm as dopants and structural nanoparticles changes of the final geopolymer formed. It is shown that the disorder formed by alkali activation of metakaolin can accommodate the rare earth cations Nd3+ and Sm3+ into their aluminosilicate framework structure. The main geopolymerization product identified in gels is Al-rich (Na)-AS-H gel comprising Al and Si in tetrahedral coordination. Na+ ions were balancing the negative charge resulting from Al3+ in tetrahedral coordination. The changes in the structures of the final product (geopolymer/Nd2O3; Sm2O3), has been characterized using X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS) and transmission electron microscopy (TEM) analysis with energy dispersive spectrometry (EDS). Nucleation at the seed surfaces leads to the formation of phase-separated gels from rare earth phase early in the reaction process. It is confirmed that Nd and Sm have been shown to form unstable hydroxides Nd(OH)3 and Sm(OH)3 that are in equilibrium with the corresponding oxides.

17.
Sci Total Environ ; 773: 145583, 2021 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-33582359

RESUMEN

Graphitic carbon nitride (g-C3N4) has emerged as a most promising photocatalyst, non-toxicity and low density, but it is plagued by low activity due to the small specific surface area and poor quantum efficiency. Morphological engineering and coupling with other materials to form hybrids have proven to be effective strategies for enabling high photocatalytic performances. Here, neodymium oxide (Nd2O3) coupled tubular g-C3N4 composites had been facilely synthesized by a solvent evaporation and high-temperature calcination method to realize efficient photocatalytic activity of hydrogen production and NO removal. A series of characterizations, such as XRD, ESR, in-situ DRIFTS, etc., were used to analyze the physical and chemical properties of the bifunctional photocatalyst, which demonstrated that the composite material had more active sites and a faster electron transfer rate. The optimal sample (1 wt% Nd2O3/CN-T) had a H2 generation rate of 4355.34 µmol·g-1·h-1, which was 9.46 times than that of original g-C3N4 obtained through heating melamine (CN-M). In addition, the NO removal rate was also 32.32% higher than that of original CN-M. On the basis of the above photocatalytic experimental results and characterizations, a possible mechanism or pathway was proposed and illustrated. This work could provide a feasible strategy to fabricate tubular g-C3N4-based composites with rare earth metal oxides (dual-factor regulation) to simultaneously enhance photocatalytic hydrogen production and NO removal efficiently (double application).

18.
Int J Nanomedicine ; 15: 387-400, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32021186

RESUMEN

INTRODUCTION: Rare-earth nanoparticles in the environment and human body pose a potential threat to human health. Although toxic effects of rare-earth nanoparticles have been extensively studied, the effects on the early development are not well understood. In this study, we attempted to explain the toxic effects of neodymium oxide (Nd2O3) nanoparticles on early development. METHODS: We added the Nd2O3 nanoparticles at different concentrations and recorded the mortality and malformation rate per 24 hrs under a microscope. The live embryos treated with Nd2O3 nanoparticles were imaged as movies and Z step lapses with a confocal microscope, and heart rates were counted for 30 s to measure the cardiac function. The live Tg (Flk1:EGFP) transgenic embryos exposed to Nd2O3 nanoparticles were observed under confocal microscope to measure the cerebrovascular development. Subsequently, we extracted the total protein for Western blot at 5 days post-fertilisation (dpf). Embryos were collected to undergo TUNEL staining for apoptosis detection. RESULTS: Nd2O3 nanoparticles disturbed embryo development at high concentrations (>200 µg/mL). The mortality and malformation rate gradually increased in a dose-dependent manner by morphological observation, while the Nd2O3 median lethal concentration (LD50) was 203.4 µg/mL at 120 hrs post-fertilisation (hpf). Furthermore, the Nd2O3-treated embryos showed severe arrhythmia and reduced heart rate. We also observed the markedly cerebrovascular disappearance at middle concentration (100 and 200 µg/mL). The downregulated autophagy flux in brain blood vessels and increased apoptosis level in neurons might affect vessels sprouting and contribute to the vanished cerebrovascular. CONCLUSION: The results suggested that the embryos exposed to Nd2O3 activated the apoptosis pathway and induced toxicity and abnormal cardiac/cerebrovascular development.


Asunto(s)
Apoptosis/efectos de los fármacos , Anomalías Cardiovasculares/inducido químicamente , Nanopartículas del Metal/toxicidad , Neodimio/toxicidad , Óxidos/toxicidad , Pez Cebra/embriología , Animales , Animales Modificados Genéticamente , Arritmias Cardíacas/inducido químicamente , Relación Dosis-Respuesta a Droga , Embrión no Mamífero/efectos de los fármacos , Femenino , Frecuencia Cardíaca/efectos de los fármacos , Larva/efectos de los fármacos , Masculino , Pruebas de Toxicidad , Pez Cebra/genética
19.
Materials (Basel) ; 13(6)2020 Mar 16.
Artículo en Inglés | MEDLINE | ID: mdl-32188051

RESUMEN

This paper reports the sol-gel synthesis of Al2O3-Nd2O3 (Al-Nd-x; x = 5%, 10%, 15% and 25% of Nd2O3) binary oxides and the photodegradation of diclofenac activated by UV light. Al-Nd-based catalysts were analyzed by N2 physisorption, XRD, TEM, SEM, UV-Vis and PL spectroscopies. The inclusion of Nd2O3 in the aluminum oxide matrix in the 10-25% range reduced the band gap energies from 3.35 eV for the γ-Al2O3 to values as low as 3.13-3.20 eV, which are typical of semiconductor materials absorbing in the UV region. γ-Al2O3 and Al-Nd-x binary oxides reached more than 92.0% of photoconverted diclofenac after 40 min of reaction. However, the photocatalytic activity in the diclofenac degradation using Al-Nd-x with Nd2O3 contents in the range 10-25% was improved with respect to that of γ-Al2O3 at short reaction times. The diclofenac photoconversion using γ-Al2O3 was 63.0% at 10 min of UV light exposure, whereas Al-Nd-15 binary oxide reached 82.0% at this reaction time. The rate constants determined from the kinetic experiments revealed that the highest activities in the aqueous medium were reached with the catalysts with 15% and 25% of Nd2O3, and these compounds presented the lowest band gap energies. The experimental results also demonstrated that Nd2O3 acts as a separator of charges favoring the decrease in the recombination rate of electron-hole pairs.

20.
Ultrason Sonochem ; 42: 171-182, 2018 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-29429658

RESUMEN

Nd2O3-SiO2 nanocomposites with enhanced photocatalytic activity have been obtained through simple and rapid sonochemical route in presence of putrescine as a new basic agent, for the first time. The influence of the mole ratio of Si:Nd, basic agent and ultrasonic power have been optimized to obtain the best Nd2O3-SiO2 nanocomposites on shape, size and photocatalytic activity. The produced Nd2O3-SiO2 nanocomposites have been characterized utilizing XRD, EDX, TEM, FT-IR, DRS and FESEM. Application of the as-formed Nd2O3-SiO2 nano and bulk structures as photocatalyst with photodegradation of methyl violet contaminant under ultraviolet illumination was compared. Results demonstrated that SiO2 has remarkable effect on catalytic performance of Nd2O3 photocatalyst for decomposition. By introducing of SiO2 to Nd2O3, decomposition efficiency of Nd2O3 toward methyl violet contaminant under ultraviolet illumination was increased.

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