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1.
Blood Cells Mol Dis ; 104: 102797, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-37826942

RESUMO

Hemoglobin Ernz (Hb Ernz) is a missense variant in ß-globin caused by a Threonine to Asparagine substitution at the 123rd amino acid position and HBB c.371C > A in gene level. Hb Ernz has been classified as Uncertain Significance (VUS) by ACMG due to limited reports and the absence of any homozygote genotypes. In our study, we found eight cases of Hb Ernz by DNA sequencing of the ß-globin gene during >20 years of Thalassemia Screening in individuals with borderline hematological parameters who were possible carriers of thalassemia or their spouses. We also report the first homozygote variant of Hb Ernz. Our findings suggest that the changes in hematological parameters observed in individuals with Hb Ernz are likely due to α-globin gene mutations rather than Hb Ernz itself. These findings support the reclassification of Hb Ernz as a benign variant in variant classification.


Assuntos
Hemoglobinas Anormais , Talassemia beta , Humanos , Homozigoto , Hemoglobinas Anormais/genética , Talassemia beta/genética , Genótipo , Mutação , Globinas beta/genética
2.
Orphanet J Rare Dis ; 15(1): 14, 2020 01 14.
Artigo em Inglês | MEDLINE | ID: mdl-31937337

RESUMO

BACKGROUND: Limb-girdle muscular dystrophies are a group of genetically heterogeneous diseases that are inherited in both autosomal dominant (LGMDD) and autosomal recessive forms (LGMDR), the latter is more common especially in populations with high consanguineous marriages like Iran. In the present study, we aimed to investigate the genetic basis of patients who are suspicious of being affected by LGMDR. DNA samples of 60 families suspected of LGMD were extracted from their whole blood. Four short tandem repeat (STR) markers for each candidate genes related to LGMD R1 (calpain3 related)- R6 (δ-sarcoglycan-related) were selected, and all these 24 STRs were applied in two sets of multiplex PCR. After autozygosity mapping, Sanger sequencing and variant analysis were done. Predicting identified variants' effect was performed using in-silico tools, and they were interpreted according to the American College of Medical Genomics and Genetics (ACMG) guideline. MLPA was used for those patients who had large deletions. Fresh muscle specimens were taken from subjects and were evaluated using the conventional panel of histochemical stains. RESULTS: forty out of sixty families showed homozygote haplotypes in CAPN3, DYSF, SGCA, and SGCB genes. The exons and intron-exon boundaries of the relevant genes were sequenced and totally 38 mutations including CAPN3 (n = 15), DYSF (n = 9), SGCB (n = 11), and SGCA (n = 3) were identified. Five out of them were novel. The most prevalent form of LGMDs in our study was calpainopathy followed by sarcoglycanopathy in which beta-sarcoglycanopathy was the most common form amongst them. Exon 2 deletion in the SGCB gene was the most frequent mutation in this study. We also reported evidence of a possible founder effect in families with mutations in DYSF and SGCB genes. We also detected a large consanguineous family suffered from calpainopathy who showed allelic heterogeneity. CONCLUSIONS: This study can expand our knowledge about the genetic spectrum of LGMD in Iran, and also suggest the probable founder effects in some Iranian subpopulations which confirming it with more sample size can facilitate our genetic diagnosis and genetic counseling.


Assuntos
Distrofia Muscular do Cíngulo dos Membros/genética , Mutação/genética , Adolescente , Adulto , Alelos , Calpaína/genética , Criança , Pré-Escolar , Análise Mutacional de DNA/métodos , Disferlina/genética , Éxons/genética , Feminino , Haplótipos/genética , Homozigoto , Humanos , Masculino , Proteínas Musculares/genética , Linhagem , Sarcoglicanas/genética , Adulto Jovem
3.
Photochem Photobiol ; 95(2): 532-542, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30225987

RESUMO

In this work, neat and supported H6 P2 W18 O62 into nanocage of ß-zeolite were synthesized. However, H6 P2 W18 O62 into nanocage of ß-zeolite was synthesized via template synthesis method. In addition, TiO2 was supported on H6 P2 W18 O62 /ß zeolite by impregnation method. The obtained materials were characterized by XRD, FT-IR, UV-Vis, FESEM and EDS techniques. Also, W and Ti contents of the catalyst were determined by ICP and EDS technique. The results reveal that the photocatalyst performance depends on catalyst loading, pH effect, and methyl orange concentration. Photocatalytic degradation of methyl orange follows a pseudo-first order kinetic. The chemical oxygen demand (COD) experimental proved mineralization of methyl orange. Another reason for degradation and mineralization of methyl orange is the absence of hydrazine at the end of reaction which is one of the photodecolorization products. The plausible mechanism for photodegradation of MO was proposed.

4.
Metab Brain Dis ; 33(5): 1689-1697, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-30022420

RESUMO

Isolated Methylmalonic acidemia/aciduria (MMA) is a group of inborn errors of metabolism disease which is caused by defect in methylmalonyl-CoA mutase (MCM) enzyme. The enzyme has a key function in the catabolism of branched chain amino acids (BCAA, isoleucine, and valine), methionine, and threonine. MCM is encoded by a single gene named "MUT". Other subtypes of MMA are caused by mutations in cblA (encoded by MMAA) and cblB (encoded by MMAB), which is involved in the synthesis of methylmalonyl-coenzyme A cofactor. Different types of mutations have been identified as the cause of MMA. However, the mutation spectrum of MMA in Iran has not been studied so far. Here, we aimed to investigate the MMA causative mutations in the Iranian population. Using STR (Short Tandem Repeat) markers, we performed autozygosity mapping to identify the potential pathogenic variants in 11 patients with clinical diagnosis of MMA. Nineteen STR markers which are linked to the MUT, MMAA and MMAB genes (the genes with known causative mutations in MMA) were selected for PCR-amplification using two recently designed multiplex PCR panels. Next, the families that were diagnosed with homozygous haplotypes for the candidate genes were directly sequenced. Five novel mutations (c.805delG, c.693delC, c.223A > T, c.668A > G and c.976A > G in MUT) were identified beside other 4 recurrent mutations (c.361insT in MUT, c.571C > T and c.197-1 G > T in MMAB and c.1075C > T in MMAA). In silico analyses were also performed to predict the pathogenicity of the identified variants. The mutation c.571C > T in MMAB was the most common mutation in our study.


Assuntos
Erros Inatos do Metabolismo dos Aminoácidos/genética , Metilmalonil-CoA Mutase/genética , Repetições de Microssatélites , Mutação , Adolescente , Criança , Pré-Escolar , Estudos de Coortes , Feminino , Humanos , Lactente , Recém-Nascido , Irã (Geográfico) , Masculino
5.
J Arrhythm ; 34(3): 286-290, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29951145

RESUMO

Jervell-Lange Nielsen syndrome (JLNS) with autosomal recessive inheritance is a congenital cardiovascular disorder characterized by prolongation of QT interval on the ECG and deafness. We have performed molecular investigation by haplotype analysis and DNA Sanger sequencing in 2 unrelated Iranian families with a history of syncope. Mutational screening of KCNQ1 gene revealed the novel homozygous frameshift mutation c.733-734delGG (p.G245Rfs*39) in 2 obviously unrelated cases of JLNS which is probably a founder mutation in Iran. The novel mutation detected in this study is the first time reported among Iranian population and will be beneficial in the tribe and region-specific cascade screening of LQTS in Iran.

6.
Anal Biochem ; 551: 29-36, 2018 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-29753720

RESUMO

In the present study, a nanocomposite of f-MWCNTs-chitosan-Co was prepared by the immobilization of Co(II) on f-MWCNTs-chitosan by a self-assembly method and used for the quantitative determination of paracetamol (PR). The composite was characterized by field emission scanning electron microscopy (FESEM) and energy dispersive x-ray analysis (EDX). The electroactivity of cobalt immobilized on f-MWCNTs-chitosan was assessed during the electro-oxidation of paracetamol. The prepared GCE modified f-MWCNTs/CTS-Co showed strong electrocatalytic activity towards the oxidation of PR. The electrochemical performances were investigated by cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS) and differential pulse voltammetry (DPV). Under favorable experimental conditions, differential pulse voltammetry showed a linear dynamic range between 0.1 and 400 µmol L-1 with a detection limit of 0.01 µmol L-1 for the PR solution. The fabricated sensor exhibited significant selectivity towards PR detection. The fabricated sensor was successfully applied for the determination of PR in commercial tablets and human serum sample.


Assuntos
Acetaminofen/análise , Técnicas Eletroquímicas/métodos , Acetaminofen/sangue , Acetaminofen/toxicidade , Analgésicos não Narcóticos/análise , Analgésicos não Narcóticos/sangue , Antipiréticos/análise , Antipiréticos/sangue , Técnicas Biossensoriais/métodos , Quitosana/química , Cobalto/química , Espectroscopia Dielétrica , Humanos , Concentração de Íons de Hidrogênio , Nanopartículas Metálicas/química , Nanopartículas Metálicas/ultraestrutura , Microscopia Eletrônica de Varredura , Nanocompostos/química , Nanocompostos/ultraestrutura , Nanotubos de Carbono/química , Nanotubos de Carbono/ultraestrutura , Espectroscopia de Infravermelho com Transformada de Fourier , Comprimidos/química
7.
Sci Rep ; 8(1): 6221, 2018 04 18.
Artigo em Inglês | MEDLINE | ID: mdl-29670168

RESUMO

Process equipment and facilities are constantly facing the dilemmas of tear and wear. This manuscript introducing functionalized reduced graphene oxide with triazole moiety via click chemistry as a anti-wear additive. While this has been achieved successfully, full characterization of the new anti-wear additive material revealed it to be promising in ameliorating issues of wears. One of the merits of the synthesized material includes reduction of contact asperity as the lipophilic alkyl chain length increases. It has been tested to be functional when formulated as an additive in group III petroleum base oil. Accordingly, it shows an irregularity in renewable base oil. Following screening evaluations of the lipophilic alkyl chain lengths, the additive with twelve carbon atoms; functionalized reduced graphene oxide, rGO-T-C(12) was confirmed to stand out among others with the good reduction of friction coefficient and the least wear scar diameter of ~539.78 µm, compared to the base oil containing no additive.

8.
J Colloid Interface Sci ; 509: 140-152, 2018 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-28898734

RESUMO

In this study, we synthesized covalently functionalized graphene nanoplatelet (GNP) aqueous suspensions that are highly stable and environmentally friendly for use as coolants in heat transfer systems. We evaluated the heat transfer and hydrodynamic properties of these nano-coolants flowing through a horizontal stainless steel tube subjected to a uniform heat flux at its outer surface. The GNPs functionalized with clove buds using the one-pot technique. We characterized the clove-treated GNPs (CGNPs) using X-ray photoelectron spectroscopy (XPS) and transmission electron microscopy (TEM). We then dispersed the CGNPs in distilled water at three particle concentrations (0.025, 0.075 and 0.1wt%) in order to prepare the CGNP-water nanofluids (nano-coolants). We used ultraviolet-visible (UV-vis) spectroscopy to examine the stability and solubility of the CGNPs in the distilled water. There is significant enhancement in thermo-physical properties of CGNPs nanofluids relative those for distilled water. We validated our experimental set-up by comparing the friction factor and Nusselt number for distilled water obtained from experiments with those determined from empirical correlations, indeed, our experimental set-up is reliable and produces results with reasonable accuracy. We conducted heat transfer experiments for the CGNP-water nano-coolants flowing through the horizontal heated tube in fully developed turbulent condition. Our results are indeed promising since there is a significant enhancement in the Nusselt number and convective heat transfer coefficient for the CGNP-water nanofluids, with only a negligible increase in the friction factor and pumping power. More importantly, we found that there is a significant increase in the performance index, which is a positive indicator that our nanofluids have potential to substitute conventional coolants in heat transfer systems because of their overall thermal performance and energy savings benefits.

9.
J Colloid Interface Sci ; 511: 318-324, 2018 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-29031151

RESUMO

Zero-dimensional graphene quantum dots (GQDs) consist of single- or few-layer graphene with a size less than 20 nm and stand for a new type of QDs with unique properties combining the graphene nature and size-resulted quantum effects. GQDs possess unique optical and electronic properties, and in particular possess a band-gap less than 2.0 eV because of quantum confinement and edge effects. In this study, we investigated the performance of DSSCs using different thicknesses of ZnO nanoparticles as a photo-anode and GQDs as a green photosensitizer. The current voltage (I-V) test results indicate that the performance of DSSCs is improved by increasing the thickness of the photo-anode and the thickness of 40 µm shows the highest efficiency for DSSC device based on ZnO nanoparticles photo-anodes. The DSSC using ZnO nanoparticles as a photo-anode with thickness of 40 µm shows almost same efficiency when we replaced N-719 with GQDs which is confirmed that using GQDs as an alternative to ruthenium based dyes is a new approach for DSSCs.

10.
PLoS One ; 12(6): e0158549, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28582420

RESUMO

Highly photocatalytically active copper chromite nanostructured material were prepared via a novel simple hydrothermal reaction between [Cu(en)2(H2O)2]Cl2 and [Cr(en)3]Cl3.3H2O at low temperature, without adding any pH regulator or external capping agent. The as-synthesized nanostructured copper chromite was analyzed by transmission electron microscopy (TEM), UV-vis diffuse reflectance spectroscopy, energy dispersive X-ray microanalysis (EDX), scanning electron microscopy (SEM), X-ray diffraction (XRD) and Fourier transform infrared (FT-IR) spectroscopy. Results of the morphological investigation of the as-synthesized products illustrate that the shape and size of the copper chromite depended on the surfactant sort, reaction duration and temperature. Moreover, the photocatalytic behavior of as-obtained copper chromite was evaluated by photodegradation of acid blue 92 (anionic dye) as water pollutant.


Assuntos
Compostos de Cromo/química , Cobre/química , Nanoestruturas/química , Naftalenos/isolamento & purificação , Poluentes Químicos da Água/isolamento & purificação , Biodegradação Ambiental , Catálise , Água Doce/química , Temperatura Alta , Humanos , Nanoestruturas/ultraestrutura , Tamanho da Partícula , Processos Fotoquímicos , Propriedades de Superfície , Temperatura
11.
Sci Rep ; 7(1): 1623, 2017 05 09.
Artigo em Inglês | MEDLINE | ID: mdl-28487527

RESUMO

A method to fabricate a bioinspired nanobiosensor using electronic-based artificial taste receptors for glucose diagnosis is presented. Fabricated bioinspired glucose nanobiosensor designated based on an artificial taste bud including an amperometric glucose biosensor and taste bud-inspired circuits. In fact, the design of the taste bud-inspired circuits was inspired by the signal-processing mechanism of taste nerves which involves two layers. The first, known as a type II cell, detects the glucose by glucose oxidase and transduces the current signal obtained for the pulse pattern is conducted to the second layer, called type III cell, to induce synchronisation of the neural spiking activity. The oscillation results of fabricated bioinspired glucose nanobiosensor confirmed an increase in the frequency of the output pulse as a function of the glucose concentration. At high glucose concentrations, the bioinspired glucose nanobiosensor showed a pulse train of alternating short and long interpulse intervals. A computational analysis performed to validate the hypothesis, which was successfully reproduced the alternating behaviour of bioinspired glucose our nanobiosensor by increasing the output frequency and alternation of pulse intervals according to the reduction in the resistivity of the biosensor.


Assuntos
Biomimética , Técnicas Biossensoriais , Glucose/análise , Nanopartículas/química , Papilas Gustativas/fisiologia , Simulação por Computador , Eletricidade , Eletroquímica , Eletrodos , Vidro/química , Nanotubos de Carbono/ultraestrutura
12.
PLoS One ; 12(5): e0162891, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28493874

RESUMO

In this work, SrCrxFe12-xO19 (x = 0.0, 0.5, 1.0, 1.5) nanostructures were successfully synthesized by sol-gel auto-combustion method, and different aminoacids were used as green reductants. Various analysis results show that SrCrxFe12-xO19 nanoparticles synthesized successfully.The present study shows that SrCrxFe12-xO19 nanoparticle could be used as adsorbent for the desulfurization of liquid fuels. Increasing of nanoparticles concentration was caused to increase the adsorption rate of sulfur contents of fuel. The adsorption rate of sulfur contents of fuel in various concentrations 4.5, 9.5, and 18.5 g. L -1 of SrCrxFe12-xO19 nanoparticles in solution was estimated about 39, 50, and 62% for 30 min, respectively. The results of catalytic tests reveals that SrCrxFe12-xO19 nanoparticles have the potential to be used as a new kind of semiconductor catalysts for the desulfurization of liquid fuels. Magnetic property of the final sample was measured at room temperature by a vibration sample magnetometer (VSM) and shown that the intrinsic coercivity of product is about 6000 Oe and it exhibits characteristics of single magnetic domains (Mr/ Ms = 0.53).


Assuntos
Catálise , Cerâmica/química , Nanopartículas/química , Cerâmica/síntese química , Nanopartículas/ultraestrutura , Transição de Fase , Semicondutores , Soluções/química , Enxofre/química
13.
J Colloid Interface Sci ; 504: 115-123, 2017 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-28531649

RESUMO

In this study, we propose an innovative, bio-based, environmentally friendly approach for the covalent functionalization of multi-walled carbon nanotubes using clove buds. This approach is innovative because we do not use toxic and hazardous acids which are typically used in common carbon nanomaterial functionalization procedures. The MWCNTs are functionalized in one pot using a free radical grafting reaction. The clove-functionalized MWCNTs (CMWCNTs) are then dispersed in distilled water (DI water), producing a highly stable CMWCNT aqueous suspension. The CMWCNTs are characterized using Raman spectroscopy, X-ray photoelectron spectroscopy and transmission electron microscopy. The electrostatic interactions between the CMWCNT colloidal particles in DI water are verified via zeta potential measurements. UV-vis spectroscopy is also used to examine the stability of the CMWCNTs in the base fluid. The thermo-physical properties of the CMWCNT nano-fluids are examined experimentally and indeed, this nano-fluid shows remarkably improved thermo-physical properties, indicating its superb potential for various thermal applications.

14.
ACS Biomater Sci Eng ; 3(9): 2059-2063, 2017 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-33440559

RESUMO

This pioneering study involved the fabrication of a new class of nanohybrid-based electrochemical glucose biosensor. First, three-dimensional (3D) graphene was fabricated as a platform of multiwalled carbon nanotube (MWCNT). Then, it was used to immobilize glucose oxidase (GOD) on nanohybrid thin film via the entrapment technique. The modified glucose biosensor indicated excellent biocatalytic activity toward the glucose measurment with a sensitivity of up to 49.58 µA mM-1 cm-2 and a wide linear dynamic range up to 16 mM. The fabricated biosensor shows an excellent stability of 87.8%, with its current diminishing after 3 months. This facile and simple electrochemical method for glucose monitoring using a modified glassy carbon electrode (GCE) by 3DG-MWCNT-GOD could open new avenues in producing of a inexpensive and sensitive glucose nanobiosensors.

15.
Sci Rep ; 6: 32539, 2016 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-27581681

RESUMO

In this work, two natural sources, including pomegranate peel extract and cochineal dye were employed for the synthesis of silver nanoparticles. The natural silver complex from pomegranate peel extract resulted in nano-sized structures through solution-phase method, but this method was not efficient for cochineal dye-silver precursor and the as-formed products were highly agglomerated. Therefore, an alternative facile solid-state approach was investigated as for both natural precursors and the results showed successful production of well-dispersed nanoparticles with narrow size distribution for cochineal dye-silver precursor. The products were characterized by X-ray diffraction (XRD), Scanning Electron Microscopy (SEM), Energy dispersive X-ray microanalysis (EDX), and Transmission Electron Microscopy (TEM).


Assuntos
Carmim/química , Corantes de Alimentos/química , Lythraceae/química , Nanopartículas Metálicas/química , Nanotecnologia/métodos , Prata/química , Frutas/química , Nanopartículas Metálicas/ultraestrutura , Conformação Molecular , Extratos Vegetais/química , Resíduos/análise
16.
J Photochem Photobiol B ; 163: 421-30, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27639172

RESUMO

This review provides a background, fundamental and advanced application of titania nanoparticles (TiO2) on the disinfection and killing of cancer cell through photocatalytic chemistry. It starts with the characteristic properties focused on the surface, light sensitivity, crystallinity and toxicology of TiO2 as a photocatalyst. Consequently, outline and design of photocatalytic reactor has been figured out based on the target organisms, including bacteria, viruses, fungi and cancer cells. Despite a large number of studies undertaken, limited selectivity and efficacy of TiO2 photocatalyst are still widely accepted problems. An ideal TiO2 photocatalyst should have the combined properties of highly stable reactive oxygen species yield and a greater degree of selectivity towards cancerous cell without damaging the healthy tissues. Hybridization of TiO2 with metal, metal oxide and carbon nano materials significantly improved both of stability and selectivity of TiO2, whilst maintaining its high Photodynamic reactivity.


Assuntos
Nanopartículas , Nanotecnologia/métodos , Neoplasias/patologia , Fotoquimioterapia/métodos , Titânio/química , Titânio/farmacologia , Catálise , Humanos , Neoplasias/tratamento farmacológico , Titânio/uso terapêutico , Titânio/toxicidade
17.
J Neurogenet ; 30(1): 1-4, 2016 03.
Artigo em Inglês | MEDLINE | ID: mdl-27276190

RESUMO

Sarcoglycanopathies (SGPs) constitute a subgroup of autosomal recessive limb girdle muscular dystrophies (LGMDs) which are caused by mutations in sarcoglycan (SGs) genes. SG proteins form a core complex consisting of α, ß, γ and δ sarcoglycans which are encoded by SGCA, SGCB, SGCG and SGCD genes, respectively. Genetic defect, in any of these SG proteins, results in instability of the whole complex. This effect can be helpful in interpreting muscle biopsy results. Autozygosity mapping is a gene mapping approach which can be applied in large consanguineous families for tracking the defective gene in most autosomal recessive disorders. In the present study, we used autozygosity mapping, to find the gene responsible for muscular dystrophy. Proband was a 10-year-old boy referred to our center for ruling out DMD (Duchenne muscular dystrophy). According to the pedigree and clinical reports, we assessed him for SGPs. Haplotyping, using the four short tandem repeat (STR) markers for each of the SG genes, showed that the phenotype may segregate with SGCB gene; and observing two crossing overs which occurred within the gene suggested that the mutation might be in the first two exons of SGCB gene. Mutation analysis showed a 26 bp duplication (10 bp before the initiation codon till 13 bp after the ATG start codon). This will cause a frameshift in protein synthesis.


Assuntos
Mapeamento Cromossômico/métodos , Distrofia Muscular do Cíngulo dos Membros/genética , Sarcoglicanas/genética , Adulto , Criança , Análise Mutacional de DNA , Feminino , Humanos , Irã (Geográfico) , Masculino , Linhagem
18.
Sci Rep ; 6: 25227, 2016 05 04.
Artigo em Inglês | MEDLINE | ID: mdl-27143126

RESUMO

This paper describes cooperate the co-absorbance (CdS QDs) and the plasmonic core-shell nanoparticles (Ag@PVP) of dye synthesized solar cells in which CdS QDs and Ag@PVP are incorporated into the TiO2 layer. Cooperative nanoparticles show superior behavior on enhancing light absorption in comparison with reference cells. Cooperated DSSC exhibits the best performance with the power conversion efficiency of 7.64% which is superior to that of the free-modified DSSC with the PCE of 5%. Detailed studies offer an effective approach to enhance the efficiency of dye synthesized solar cells.

19.
Sci Rep ; 6: 25231, 2016 05 04.
Artigo em Inglês | MEDLINE | ID: mdl-27143312

RESUMO

In this work, copper pyrovanadate (Cu3V2O7(OH)2(H2O)2) nanoparticles have been synthesized by a simple and rapid chemical precipitation method. Different copper-organic complexes were used to control the size and morphology of products. The morphology and structure of the as-synthesized products were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), Fourier transform infrared (FT-IR) spectrum, electron dispersive X-ray spectroscopy (EDX), thermal gravimetric analysis (TGA), differential thermal analysis (DTA) and photoluminescence (PL) spectroscopy. The influence of copper pyrovanadate nanostructures on the flame retardancy of the polystyrene, poly vinyl alcohol and cellulose acetate was studied. Dispersed nanoparticles play the role of a magnetic barrier layer, which slows down product volatilization and prevents the flame and oxygen from the sample during decomposition of the polymer. Cu3V2O7(OH)2(H2O)2 is converted to Cu3V2O8 with an endothermic reaction which simultaneously releases water and decrease the temperature of the flame region.

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