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1.
Artigo em Inglês | MEDLINE | ID: mdl-38653896

RESUMO

The modern world requires a chemical industry that can run at low production costs while producing high-quality products with minimal environmental impact. The development of environmentally friendly, cost-effective, and efficient wastewater treatment materials remains a major problem for the sustainable approach. We prepared nanoscale cadmium sulfide (CdS)-enwrapped polypyrrole (PPy) polymer composites for degradation of organic pollutants. The prepared CdS@PPy nanocomposites were characterized by powder X-ray diffraction, scanning electron microscope (SEM), field emission scanning electron microscope (FESEM), Fourier transform infrared spectroscopy (FTIR), and ultraviolet-visible (UV) absorption spectroscopy, indicating proper intercalation between CdS and PPy. Consequently, the catalytic efficiency of the synthesized hybrid nanocomposites was analyzed through the degradation of methylene blue (MB) and rhodamine B (Rh B) under visible light irradiation. The measured degradation efficiency of the dye solutions under the photolysis process is about 18% and 23% for MB and Rh B dye, respectively. Furthermore, the recycle test result concludes that the CdS@PPy composite exhibits 91% and 89% of MB and Rh B dye degradation efficiency even at the 4th cycle, respectively. The positive synergistic impact of CdS and PPy may be the result of effective photocatalytic degradation of MB and RhB.

2.
Materials (Basel) ; 17(8)2024 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-38673251

RESUMO

Novel flake-like Ni1-xSnxO2 particles were successfully prepared by template-free hydrothermal synthesis. The prepared samples were investigated for their properties by different characterization techniques. Scanning micrographs showed that the obtained particles consisted of nanoflakes. The X-ray diffraction results of the Ni1-xSnxO2 revealed the formation of mixed-phase Ni/SnO2 having the typical tetragonal structure of SnO2, and the cubic structure of Ni in a nanocrystalline nature. The doping with Ni had a certain influence on the host's lattice structure of SnO2 at different doping concentrations. Confirmation of the functional groups and the elements in the nanomaterials was accomplished using FTIR and EDS analyses. The electrochemical performance analysis of the prepared nanomaterials were carried out with the help of the CV, GCD, and EIS techniques. The specific capacitance of the synthesized nanomaterials with different concentrations of Ni dopant in SnO2 was analyzed at different scanning rates. Interestingly, a 5% Ni-doped SnO2 nanocomposite exhibited a maximum specific capacitance of 841.85 F g-1 at 5 mV s-1 in a 6 M KOH electrolyte. Further, to boost the electrochemical performance, a redox additive electrolyte was utilized, which exhibited a maximum specific capacitance of 2130.33 at 5 mV s-1 and an excellent capacitance retention of 93.22% after 10,000 GCD cycles. These excellent electrochemical characteristics suggest that the Ni/SnO2 nanocomposite could be utilized as an electrode material for high-performance supercapacitors.

3.
Microorganisms ; 12(3)2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38543559

RESUMO

Pollutants can exist in the soil for a long time and alter the bacterial community. Using lubricants to prevent the wear of chainsaw blades is necessary for thinning activities and wood harvesting. We investigated the influences of soil contamination with chainsaw lubricants on soil bacterial communities. Bio-oil, mineral oil, and recycled oil were scattered on each treatment to investigate variations in soil bacterial structure during treated periods using the Illumina MiSeq sequencing platform. The results obtained were 5943 ASVs, 5112 ASVs, and 6136 ASVs after treatment at one month, six months, and twelve months, respectively. There was a significant difference in Shannon and Simpson indices between treatments and controls. A total of 46 bacterial genera with an average relative abundance of more than 1.0% were detected in all soil samples. Massilia was the most common genus detected in control at one month, with an average relative abundance of 14.99%, while Chthoniobacter was the most abundant genus detected in bio-oil, mineral oil, and recycled oil treatments at one month, with an average relative abundance of 13.39%, 14.32%, and 10.47%, respectively. Among the three chainsaw lubricants, bio-oil and mineral oil had fewer impacts than recycled oil. The abundances of several functional bacteria groups in the bio-oil treatment were higher than in other treatments and controls. Our results indicated that different chainsaw lubricants and their time of application affected the soil bacterial community composition.

4.
Discov Nano ; 18(1): 155, 2023 Dec 18.
Artigo em Inglês | MEDLINE | ID: mdl-38108894

RESUMO

The advancement of multidrug-resistant bacterial strains and their adverse effects is one of the most significant global health issues. The perovskite nanomaterial with combined antioxidant and antibacterial activities in one molecule has the potential for improved therapeutic solutions. In this work, Yttrium-doped Lanthanum Titanate (LaTi1 -xYxO3, where x = 0, 0.05, and 0.1) was synthesized using auto combustion technique. Excellent crystalline structure with a tetragonal system is revealed by X-ray diffraction analysis (XRD). UV-Visible diffuse reflectance spectroscopy (UV-Vis DRS), Fourier transform infrared (FTIR), and photoluminescence (PL) were used to study its optical characteristics. The field emission scanning electron microscope (FE-SEM) shows rod-like pellet-shaped Yttrium-doped nanostructures, and the elements present were confirmed with the Energy Dispersive X-Ray Analysis (EDAX). Various concentrations of the synthesized materials were tested for antibacterial activity against Gram-positive (Staphylococcus aureus 902) and Gram-negative (E. coli 443) strains using the agar-well diffusion method with gentamicin antibiotic as a positive control. High antibacterial activity of 87.1% and 83.3% was shown by 10% Yttrium-doped LaTiO3 (LY(0.1)TO) at 500 mg/mL against both positive and negative stains, respectively. Moreover, the antioxidant properties of synthesized materials were assessed with IC50 values of 352.33 µg/mL, 458.055 µg/mL, and 440.163 µg/mL for samples LaTi1 - xYxO3, where x = 0, 0.05, and 0.1 respectively. The antibacterial and antioxidant capabilities of the proposed samples illustrate their applicability in various biomedical applications.

5.
Heliyon ; 9(12): e23105, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38149182

RESUMO

The present work focuses on the structural, morphological, electrical characteristics, and antibacterial activity of mesoporous silicon (PS) against S. aureus and E. coli. We depict the structural and antimicrobial activity of PS as a result of different etching times (10.0, 20.0, 30.0, 40.0, 50.0, and 60.0 min) with a current density of 100 mA/cm2. The structural and morphological characteristics of synthesized PS have been examined with Fourier-transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), and atomic force microscopy (AFM). FTIR spectra have been used to confirmed the Si-O, Si-O-Si bond and the adsorption on the surface of PS nanoparticles. The formation of pores on the c-Si wafer results in an analysis of a photoluminescence (PL) band at 712 nm, which changes with etching time in a process similar to current density. The correlation exist among etching times and the ideality factor (η) and barrier height (фb). Gram-positive (S. aureus) and Gram-negative (E. coli) bacteria showed enhanced antimicrobial activity against the PS nanoparticles. The synthesized of PS has been shown with good electrical and antimicrobial activities.

6.
Nanomaterials (Basel) ; 13(17)2023 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-37687002

RESUMO

This work reports on the photocatalytic activity of tin oxide (SnO2)-doped magnesium (Mg) and fluorine (F) nanoparticles for methyl orange and safranin dye degradation under sunlight irradiation. Nanocatalysis-induced dye degradation was examined using UV-visible spectroscopy and a pseudo-first-order kinetics model. The results indicate that the prepared nanoparticles exhibit superior photocatalytic activity, and the degradation of methyl orange (MO) dye is approximately 82%. In contrast, the degradation of safranin dye is 96% in the same time interval of 105 min. The calculated crystallite size of the SnO2-Mg-F nanocomposite is 29.5 nm, which respects the particle size found in the DLS analysis with a tetragonal structure and spherical morphology affirmed. The optical characteristics were assessed, and their respective bandgap energies were determined to be 3.6 eV. The influence of F in Mg and SnO2 is recognized with the XRD and FT-IR spectra of the prepared particles.

7.
Int J Mol Sci ; 24(12)2023 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-37373255

RESUMO

A high perovskite activity is sought for use in magnetic applications. In this paper, we present the simple synthesis of (2.5% and 5%) Tellurium-impregnated-LaCoO3 (Te-LCO), Te and LaCoO3 (LCO) by using a ball mill, chemical reduction, and hydrothermal synthesis, respectively. We also explored the structure stability along with the magnetic properties of Te-LCO. Te has a rhombohedral crystal structure, whereas Te-LCO has a hexagonal crystal system. The reconstructed Te was imbued with LCO that was produced by hydrothermal synthesis; as the concentration of the imbuing agent grew, the material became magnetically preferred. According to the X-ray photoelectron spectra, the oxidation state of the cobaltite is one that is magnetically advantageous. As a result of the fact that the creation of oxygen-deficient perovskites has been shown to influence the mixed (Te4+/2-) valence state of the incorporated samples, it is abundantly obvious that this process is of utmost significance. The TEM image confirms the inclusion of Te in LCO. The samples start out in a paramagnetic state (LCO), but when Te is added to the mixture, the magnetic state shifts to a weak ferromagnetic one. It is at this point that hysteresis occurs due to the presence of Te. Despite being doped with Mn in our prior study, rhombohedral LCO retains its paramagnetic characteristic at room temperature (RT). As a result, the purpose of this study was to determine the impacts of RT field dependency of magnetization (M-H) for Te-impregnated LCO in order to improve the magnetic properties of RT because it is a low-cost material for advanced multi-functional and energy applications.

8.
Nanomaterials (Basel) ; 13(9)2023 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-37177068

RESUMO

New NiSn(OH)6 hexahydroxide nanoparticles were synthesised through a co-precipitation method using various concentrations of Ni2+ and Sn4+ ions (e.g., 1:0, 0:1, 1:2, 1:1, and 2:1; namely, N, S, NS-3, NS-2, and NS-1) with an ammonia solution. The perovskite NiSn(OH)6 was confirmed from powder X-ray diffraction and molecule interactions due to different binding environments of Ni, Sn, O, and water molecules observed from an FT-IR analysis. An electronic transition was detected from tin (Sn 3d) and nickel (Ni 2p) to oxygen (O 2p) from UV-Vis/IR spectroscopy. Photo luminescence spectroscopy (PL) identified that the emission observed at 400-800 nm in the visible region was caused by oxygen vacancies due to various oxidation states of Ni and Sn metals. A spherical nanoparticle morphology was observed from FE-SEM; this was due to the combination of Ni2+ and Sn4+ increasing the size and porosity of the nanoparticle. The elemental (Ni and Sn) distribution and binding energy of the nanoparticle were confirmed by EDAX and XPS analyses. Among the prepared various nanoparticles, NS-2 showed a maximum specific capacitance of 607 Fg-1 at 1 Ag-1 and 56% capacitance retention (338 Fg-1 and 5 Ag-1), even when increasing the current density five times, and excellent cycle stability due to combining Ni2+ with Sn4+, which improved the ionic and electrical conductivity. EIS provided evidence for NS-2's low charge transfer resistance compared with other prepared samples. Moreover, the NS-2//AC (activated carbon) asymmetric supercapacitor exhibited the highest energy density and high-power density along with excellent cycle stability, making it the ideal material for real-time applications.

9.
PLoS One ; 15(10): e0240300, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33027277

RESUMO

A thermochemical nonequilibrium analysis was performed under the low enthalpy shock-tunnel flows. A quasi-one-dimensional flow calculation was employed by dividing the flow calculations into two parts, for the shock-tube and the Mach 6 nozzle. To describe the thermochemical nonequilibrium of the low enthalpy shock-tunnel flows, a three-temperature model is proposed. The three-temperature model treats the vibrational nonequilibrium of O2 and NO separately from the single nonequilibrium energy mode of the previous two-temperature model. In the three-temperature model, electron-electronic energies and vibrational energy of N2 are grouped as one energy mode, and vibrational energies of O2, O2+, and NO are grouped as another energy mode. The results for the shock-tunnel flows calculated using the three-temperature model were then compared with existing experimental data and the results obtained from one- and two-temperature models, for various operating conditions of the K1 shock-tunnel facility. The results of the thermochemical nonequilibrium analysis of the low enthalpy shock-tunnel flows suggest that the nonequilibrium characteristics of N2 and O2 need to be treated separately. The vibrational relaxation of O2 is much faster than that of N2 in low enthalpy condition, and the dissociation rate of O2 is manly influenced by the species vibrational temperature of O2. The proposed three-temperature model is able to describe the thermochemical nonequilibrium characteristics of N2 and O2 behind the incident and reflected shock waves, and the rapid vibrational freezing of N2 in nozzle expanding flows.


Assuntos
Fenômenos Mecânicos , Temperatura , Modelos Teóricos
10.
Plant Pathol J ; 35(4): 381-387, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31481861

RESUMO

For several years, temperatures in the Korean peninsula have gradually increased due to climate change, resulting in a changing environment for growth of crops and vegetables. An associated consequence is that emerging species of insect vector have caused increased viral transmission. In Jeju Island, Korea, occurrences of viral disease have increased. Here, we report characterization of five newly collected turnip mosaic virus (TuMV) isolates named KBJ1, KBJ2, KBJ3, KBJ4 and KBJ5 from a survey on Jeju Island in 2017. Full-length cDNAs of each isolate were cloned into the pJY vector downstream of cauliflower mosaic virus 35S and bacteriophage T7 RNA polymerase promoters. Their fulllength sequences share 98.9-99.9% nucleotide sequence identity and were most closely related to previously reported Korean TuMV isolates. All isolates belonged to the BR group and infected both Chinese cabbage and radish. Four isolates induced very mild symptoms in Nicotiana benthamiana but KBJ5 induced a hypersensitive response. Symptom differences may result from three amino acid differences uniquely present in KBJ5; Gly(382)Asp, Ile(891)Val, and Lys(2522)Glu in P1, P3, and NIb, respectively.

11.
Phytopathology ; 109(9): 1638-1647, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31044662

RESUMO

Infectious clones of Korean turnip mosaic virus (TuMV) isolates KIH1 and HJY1 share 88.1% genomic nucleotides and 96.4% polyprotein amino acid identity, and they induce systemic necrosis or mild mosaic, respectively, in Nicotiana benthamiana. Chimeric constructs between these isolates exchanged the 5', central, and 3' domains of KIH1 (K) and HJY1 (H), where the order of the letters indicates the origin of these domains. KIH1 and chimeras KHH and KKH induced systemic necrosis, whereas HJY1 and chimeras HHK, HKK, and HKH induced mild symptoms, indicating the determinant of necrosis to be within the 5' 3.9 kb of KIH1; amino acid identities of the included P1, Helper component protease, P3, 6K1, and cylindrical inclusion N-terminal domain were 90.06, 98.91, 93.80, 100, and 100%, respectively. Expression of P1 or P3 from a potato virus X vector yielded symptom differences only between P3 of KIH1 and HJY1, implicating a role for P3 in necrosis in N. benthamiana. Chimera KKH infected Brassica rapa var. pekinensis 'Norang', which was resistant to both KIH1 and HJY1, indicating that two separate TuMV determinants are required to overcome the resistance. Ability of diverse TuMV isolates, chimeras, and recombinants to overcome resistance in breeding lines may allow identification of novel resistance genes.


Assuntos
Brassica , Nicotiana , Brassica/virologia , Quimera , Doenças das Plantas/microbiologia , Potyvirus , Nicotiana/virologia
13.
Arch Virol ; 164(6): 1553-1565, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30923966

RESUMO

Two isolates of Youcai mosaic virus (YoMV) were obtained, and their full-length genomic sequences were determined. Full-length infectious cDNA clones of each isolate were generated in which the viral sequence was under the control of dual T7 and 35S promoters for both in vitro transcript production and agro-infiltration. Comparison of the predicted amino acid sequences of the encoded proteins revealed only four differences between the isolates: three in the RNA-dependent RNA polymerase (RdRp) (V383I and M492I in the 125-kDa protein and T1245M in the 182-kDa protein); and one in the overlapping region of the movement protein (MP) and coat protein (CP) genes, affecting only the N-terminal domain of CP (CP M17T). One of the isolates caused severe symptoms in Nicotiana benthamiana plants, while the other caused only mild symptoms. In order to identify the amino acid residues associated with symptom severity, chimeric constructs were generated by combining parts of the two infectious YoMV clones, and the symptoms in infected plants were compared to those induced by the parental isolates. This allowed us to conclude that the M17T substitution in the N-terminal domain of CP was responsible for the difference in symptom severity. The M17T variation was found to be unique among characterized YoMV isolates. A difference in potential post-translational modification resulting from the presence of a predicted casein kinase II phosphorylation site only in the CP of isolate HK2 may be responsible for the symptom differences.


Assuntos
Nicotiana/virologia , Polimorfismo de Nucleotídeo Único , Tobamovirus/patogenicidade , Fatores de Virulência/genética , Proteínas do Capsídeo/genética , Proteínas do Capsídeo/metabolismo , Doenças das Plantas , Processamento de Proteína Pós-Traducional , Fases de Leitura , Análise de Sequência de Proteína , Tobamovirus/genética , Proteínas Virais/genética , Proteínas Virais/metabolismo , Fatores de Virulência/metabolismo
14.
Phytopathology ; 109(5): 904-912, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30629482

RESUMO

Infectious clones were generated from 17 new Korean radish isolates of Turnip mosaic virus (TuMV). Phylogenetic analysis indicated that all new isolates, and three previously characterized Korean radish isolates, belong to the basal-BR group (indicating that the pathotype can infect both Brassica and Raphanus spp.). Pairwise analysis revealed genomic nucleotide and polyprotein amino acid identities of >87.9 and >95.7%, respectively. Five clones (HJY1, HJY2, KIH2, BE, and prior isolate R007) had lower sequence identities than other isolates and produced mild symptoms in Nicotiana benthamiana. These isolates formed three distinct sequence classes (HJY1/HJY2/R007, KIH2, and BE), and several differential amino acid residues (in P1, P3, 6K2, and VPg) were present only in mild isolates HJY1, HJY2, and R007. The remaining isolates all induced systemic necrosis in N. benthamiana. Four mild isolates formed a phylogenetic subclade separate from another subclade including all of the necrosis-inducing isolates plus mild isolate KIH2. Symptom severity in radish and Chinese cabbage genotypes was not correlated with pathogenicity in N. benthamiana; indeed, Chinese cabbage cultivar Norang was not infected by any isolate, whereas Chinese cabbage cultivar Chusarang was uniformly susceptible. Four isolates were unable to infect radish cultivar Iljin, but no specific amino acid residues were correlated with avirulence. These results may lead to the identification of new resistance genes against TuMV.


Assuntos
Brassica rapa/virologia , Nicotiana/virologia , Potyvirus/genética , Raphanus/virologia , Especificidade de Hospedeiro , Filogenia , Doenças das Plantas/virologia , Potyvirus/patogenicidade , Virulência
15.
Plant Pathol J ; 33(6): 608-613, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29238285

RESUMO

The full-length sequence of a new isolate of Apple chlorotic leaf spot virus (ACLSV) from Korea was divergent, but most closely related to the Japanese isolate A4, at 84% nucleotide identity. The full-length cDNA of the Korean isolate of ACLSV was cloned into a binary vector downstream of the bacteriophage T7 RNA promoter and the Cauliflower mosaic virus 35S promoter. Chenopodium quinoa was successfully infected using in vitro transcripts synthesized using the T7 promoter, detected at 20 days post inoculation (dpi), but did not produce obvious symptoms. Nicotiana occidentalis and C. quinoa were inoculated through agroinfiltration. At 32 dpi the infection rate was evaluated; no C. quinoa plants were infected by agroinfiltration, but infection of N. occidentalis was obtained.

16.
Virus Genes ; 53(2): 286-299, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-27913980

RESUMO

Seed-transmitted viruses have caused significant damage to watermelon crops in Korea in recent years, with cucumber green mottle mosaic virus (CGMMV) infection widespread as a result of infected seed lots. To determine the likely origin of CGMMV infection, we collected CGMMV isolates from watermelon and melon fields and generated full-length infectious cDNA clones. The full-length cDNAs were cloned into newly constructed binary vector pJY, which includes both the 35S and T7 promoters for versatile usage (agroinfiltration and in vitro RNA transcription) and a modified hepatitis delta virus ribozyme sequence to precisely cleave RNA transcripts at the 3' end of the tobamovirus genome. Three CGMMV isolates (OMpj, Wpj, and Mpj) were separately evaluated for infectivity in Nicotiana benthamiana, demonstrated by either Agroinfiltration or inoculation with in vitro RNA transcripts. CGMMV nucleotide identities to other tobamoviruses were calculated from pairwise alignments using DNAMAN. CGMMV identities were 49.89% to tobacco mosaic virus; 49.85% to pepper mild mottle virus; 50.47% to tomato mosaic virus; 60.9% to zucchini green mottle mosaic virus; and 60.96% to kyuri green mottle mosaic virus, confirming that CGMMV is a distinct species most similar to other cucurbit-infecting tobamoviruses. We further performed phylogenetic analysis to determine relationships of our new Korean CGMMV isolates to previously characterized isolates from Canada, China, India, Israel, Japan, Korea, Russia, Spain, and Taiwan available from NCBI. Analysis of CGMMV amino acid sequences showed three major clades, broadly typified as 'Russian,' 'Israeli,' and 'Asian' groups. All of our new Korean isolates fell within the 'Asian' clade. Neither the 128 nor 186 kDa RdRps of the three new isolates showed any detectable gene silencing suppressor function.


Assuntos
Cucumis sativus/virologia , Cucumovirus/genética , Filogenia , Doenças das Plantas/genética , Bacteriófago T7/genética , Citrullus/virologia , Cucumovirus/patogenicidade , Cucurbitaceae/virologia , DNA Complementar/genética , Genoma Viral , Doenças das Plantas/virologia , Regiões Promotoras Genéticas , Nicotiana/virologia , Vírus do Mosaico do Tabaco/genética , Tobamovirus/genética
17.
Langmuir ; 27(6): 2717-22, 2011 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-21291243

RESUMO

We describe photopatterning technique that employs the photodegradation of cell-adhesive-modified poly(ethyleneimine) (m-PEI) to fabricate precise micropatterns on the indium tin oxide (ITO) substrate for guided neuronal growth. The photodegradation of m-PEI coated on hydroxyl group-terminated ITO substrate created micropatterns over a large area through deep UV irradiation. The photopatterned m-PEI layer can effectively guide neurite outgrowth and control neurite extensions from individual neurons.


Assuntos
Neurônios/citologia , Polietilenoimina/química , Adesão Celular , Processos Fotoquímicos , Compostos de Estanho/química , Raios Ultravioleta
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