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1.
Artigo em Inglês | MEDLINE | ID: mdl-38655915

RESUMO

An easy way of synthesizing low-cost carbon nanomaterials without the need for high-temperature processing approach is critical for energy storage applications because the demand has increased for affordable, long-term, and environmentally friendly synthesized carbon-based materials. Herein, we synthesized multilayered graphitic carbon nano-onions (CNOs) using an oil-wick flame pyrolysis approach, employing biowaste (chicken fat) oil as a cost-effective precursor. The prepared CNOs can provide enhanced ion movement and less resistance for electron transport by interconnecting CNO particles with one another. Furthermore, heteroatom (S,N)-doped CNOs (h-CNOs) were synthesized to optimize the hydrophilic and conductive properties of carbon materials, which eventually exalted the capacitive charge transfer kinetics. The h-CNOs demonstrated superior, highest specific capacitance of 261 F/g, while the undoped CNOs showed a capacitance of 180.6 F/g at a current density of 1 A/g. In addition to capacitance, the h-CNOs also demonstrated a rate capability of 69% and a good cycling stability of 97.5% under high current densities. An asymmetric supercapacitor was fabricated using the h-CNOs as the negative and MnCo2S4 (MCS) as the positive electrode. The device showed high energy and power performance of 32.8 Wh/kg and 7350 W/kg, respectively, with a capacitance retention of 97% over 5000 cycles. Considering the facile strategic way to produce novel carbonaceous materials derived from biowaste oil (chicken fat oil), this could be considered a potential advantage for commercial energy storage devices and may open the door to producing inexpensive, industrially revolutionizing energy storage devices.

2.
J Environ Manage ; 352: 120082, 2024 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-38232595

RESUMO

New photoactive materials with uniform and well-defined morphologies were developed for efficient and sustainable photoelectrochemical (PEC) water splitting and hydrogen production. The investigation is focused on hydrothermal deposition of zinc oxide (ZnO) onto indium tin oxide (ITO) conductive surfaces and optimization of hydrothermal temperature for growing uniform sized 3D ZnO morphologies. Fine-tuning of hydrothermal temperature enhanced the scalability, efficiency, and performance of ZnO-decorated ITO electrodes used in PEC water splitting. Under UV light irradiation and using eco-friendly low-cost hydrothermal process in the presence of stable ZnO offered uniform 3D ZnO, which exhibited a high photocurrent of 0.6 mA/cm2 having stability up to 5 h under light-on and light-off conditions. The impact of hydrothermal temperature on the morphological properties of the deposited ZnO and its subsequent performance in PEC water splitting was investigated. The work contributes to advancement of scalable and efficient fabrication technique for developing energy converting photoactive materials.


Assuntos
Nanoestruturas , Óxido de Zinco , Óxido de Zinco/química , Água/química , Nanoestruturas/química , Compostos de Estanho/química
3.
Sci Rep ; 13(1): 5776, 2023 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-37031237

RESUMO

A heterojunction photocathode of CuO and CuBi2O4 grown on an FTO substrate (FTO/CuO/CuBi2O4) was synthesized using hydrothermal method followed by spin coating and annealing to overcome the bottlenecks encountered by CuO in photoelectrochemical (PEC) water splitting application. The synthesis methods, morphological, structural properties, and composition of each sample under each synthesis condition are discussed in detail. The photocathode with 15 coating layers annealed at 450 °C exhibited the best PEC performance. Moreover, its current density reached 1.23 mA/cm2 under an applied voltage of - 0.6 V versus Ag/AgCl in a neutral electrolyte. Additionally, it exhibited higher stability than the bare CuO thin film. The bonding of CuBi2O4 on CuO resulted in close contact between the two semiconductors, helping the semiconductors support each other to increase the PEC efficiency of the photocathode. CuO acted as the electron-generating layer, and the CuBi2O4 layer helped minimize photocorrosion as well as transport the carriers to the electrode/electrolyte interface to accomplish the hydrogen evolution reaction.

4.
J Environ Manage ; 332: 117397, 2023 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-36731414

RESUMO

The growth of advanced micro-and nanostructures with metal oxides has consistently generated extraordinary interest in energy and environmental applications. Cutting-edge nanostructures exhibit superior reactive sites and surface areas, thus improving the performance in crucial domains. In this study, sharp-edged pencil-type ZnO flowers and BiOI flakes as pristine materials, and their composition with carbon nanofibers (CNFs) (ZnO-BiOI@CNFs) as a hetero hybrid catalyst as well as binary compositions such as ZnO-BiOI, ZnO@CNFs, and BiOI@CNFs catalysts were fabricated using a simple and convenient hydrothermal synthesis process. The composition of newly produced innovative nanostructures was examined for azo dye degradation under solar simulator exposure. Dye degradation of ∼95% was achieved by the hybrid catalyst (ZnO-BiOI@CNFs) during 120 min of irradiation, which was ∼1.8 and 2.1-times higher than pristine ZnO and BiOI nanostructures, respectively. The improved hybrid catalysts were able to degrade methyl orange (MO) and rhodamine B (RhB) dyes. Importantly, mixed dyes RhB, MO, and azo dye demonstrated 47% dye degradation using a hybrid catalyst. These mixed dye-scalable hybrid catalyst performances offer additional insights into commercialization/industrialization. The outstanding performance of the hybrid catalyst is attributed to the unidirectional electron flow with pencil-like ZnO, a catalyst with a larger absorption zone, high surface area, and reactive sites, particularly ZnO and BiOI nanostructures, and decreased recombination rate with a heterojunction interface. In addition, CNFs can operate as electron traps and sinks, providing very quick redox reactions. To produce the sophisticated nanostructures with homogeneous morphologies, this work presents new insights into energy and environmental applications.


Assuntos
Poluentes Ambientais , Fabaceae , Nanofibras , Óxido de Zinco , Compostos Azo , Carbono , Corantes , Água
5.
Obstet Gynecol Sci ; 62(6): 483-486, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31777747

RESUMO

Microinvasive adenocarcinoma is not as well studied as microinvasive squamous cell carcinoma because diagnosis of adenocarcinoma cannot be ascertained for early invasive lesions. However, most clinicians consider a depth of invasion of 3 mm without lympho-vascular space invasion as the maximum limit for conservative management. Microinvasive cervical adenocarcinoma is characterized by a rare incidence of lymph node metastasis and very good prognosis. We describe a 62-year-old patient with an extremely early cervical adenocarcinoma which was detected only by endocervical curettage. However, she had multiple macroscopic pelvic node metastases. Clinicians should consider the probability of lymph node metastasis, although management of stage IA1 cervical adenocarcinoma may still be conservative.

6.
Molecules ; 24(19)2019 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-31575069

RESUMO

Herein, we report the design and synthesis strategy of a new class of five EDOT based co-sensitizers (CSGR1-5) by introducing different donors (2,3,4-trimethoxypheny, 2,4-dibutoxyphenyl, and 2,4-difluorophenyl) and anchoring groups (rhodamine-3-acetic acid and cyanoacetic acid) systematically. The synthesized metal-free organic co-sensitizers were employed for cocktail dye-sensitized solar cells along with N749 (black dye). The DSSC devices with a mixture of co-sensitizers (CSGR1-5) and N749 have shown a 7.95%, 8.40%, 7.81%, 6.56% and 6.99% power conversion efficiency (PCE) respectively, which was more than that of single N749 dye PCE (6.18%). Enhanced efficiency could be ascribed to the increased short circuit current (Jsc) and open circuit voltage (Voc). The increased Jsc was achieved due to enhanced light harvesting nature of N749 device upon co-sensitization with CSGR dyes and feasible energy levels of both the dyes. The Voc was improved due to better surface coverage which helps in decreasing the rate of recombination. The detailed optical and electrochemical properties were investigated and complimented with theoretical studies (DFT).


Assuntos
Fontes de Energia Elétrica , Energia Solar , Tiofenos/química , Corantes/química , Eletroquímica , Modelos Moleculares , Conformação Molecular , Análise Espectral
7.
Plant Physiol ; 176(1): 717-729, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-29114079

RESUMO

We investigated the biological roles of the Arabidopsis (Arabidopsis thaliana) GROWTH-REGULATING FACTOR (GRF) and GRF-INTERACTING FACTOR (GIF) transcriptional complex in the development of gynoecia and anthers. There are nine GRFs and three GIFs in Arabidopsis, and seven GRFs are posttranscriptionally silenced by microRNA396 (miR396). We found that overexpression of MIR396 in the gif1 gif2 double mutant background (gif1 gif2 35S:MIR396) resulted in neither ovary nor pollen. Histological and molecular marker-based analyses revealed that the mutant gynoecial primordia failed to develop carpel margin meristems and mature flowers lacked the ovary, consisting only of the stigma, style, and replum-like tissues. The mutant anther primordia were not able to form the pluripotent archesporial cells that produce pollen mother cells and microsporangia. Multiple combinations of GRF mutations also displayed the same phenotypes, indicating that the GRF-GIF duo is required for the formation of those meristematic and pluripotent cells. Most GRF proteins are localized and abundant in those cells. We also found that the weak gynoecial defects of pinoid-3 (pid-3) mutants were remarkably exacerbated by gif1 gif2 double mutations and 35S:MIR396, so that none of the gynoecia produced by gif1 gif2 pid-3 and 35S:MIR396 pid-3 developed ovaries at all. Moreover, gif1 gif2 double mutations and 35S:MIR396 also acted synergistically with 1-N-naphthylphthalamic acid in forming aberrant gynoecia. The results altogether suggest that the GRF-GIF duo regulates the meristematic and pluripotent competence of carpel margin meristems and the archesporial cell lineage and that this regulation is implemented in association with auxin action, ultimately conferring reproductive competence on Arabidopsis.


Assuntos
Proteínas de Arabidopsis/metabolismo , Flores/citologia , Flores/metabolismo , Meristema/citologia , Meristema/metabolismo , Flores/ultraestrutura , Regulação da Expressão Gênica de Plantas , Glucuronidase/metabolismo , Meristema/ultraestrutura , Mutação/genética , Fenótipo , Plantas Geneticamente Modificadas , Células-Tronco Pluripotentes/metabolismo
8.
J Nanosci Nanotechnol ; 13(9): 6236-9, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24205636

RESUMO

Zinc oxide (ZnO) nanorods with a-axis orientation were grown on a Si(100) substrate by a hydrothermal method, following which a post-annealing process was carried out at various temperatures ranging from 500 to 900 degrees C in vacuum. Atomic force microscopy (AFM), scanning electron microscopy (SEM), X-ray diffraction (XRD), and photoluminescence (PL) were carried out to investigate the structural and optical properties of the a-axis oriented ZnO nanorods. The XRD pattern of the a-axis oriented ZnO nanorods shows three diffraction peaks at 31.84 degrees, 34.48 degrees, and 66.43 degrees, corresponding to ZnO (100), ZnO (002), and ZnO (200), respectively. The texture coefficient (TC) ratio of the a-axis to the c-axis is increased with the annealing temperature. The residual tensile stress of the a-axis oriented ZnO nanorods is increased and the bond length is slightly decreased with increasing the annealing temperature. The near-band-edge emission (NBE) peak of the a-axis oriented ZnO nanorods is blue-shifted by the annealing process.

9.
J Craniofac Surg ; 23(3): 693-5, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22565879

RESUMO

PURPOSE: Facial asymmetry can be produced by congenital or acquired factors, and surgical correction is one of the very important and difficult fields in plastic surgery. Zygoma plays a key role to keep facial symmetry, and diverse methods have been tried to correct asymmetric face. We used the malarplasty with tripod osteotomy to correct nontraumatic asymmetric face. METHOD: From December 2008 to February 2010, 3 patients presenting with facial asymmetry and enophthalmia were selected, and their average age was 18 years. One of the patients has undergone surgeries 4 times without improvement for rare facial cleft no. 4 from other hospitals. The other 2 cases had hypoplastic zygoma complex caused by early enucleation and radiation therapies because of retinoblastoma in their childhood. Through a bicoronal approach, malarplasty and calvarial bone graft were done after tripod osteotomy including the zygomaticofrontal suture, zygomatic arch, and zygoma body. RESULTS: The surgery results were evaluated by radiographic inspection and the photographs of the patients. Differences in preoperative heights of both normal and hypoplastic zygoma-orbit complex in Waters and zygomatic view were estimated. After corrective operation, the height of the zygoma complex was almost close to normal height, and orbital volume was increased, and ectropion was corrected at the same time in patients. CONCLUSIONS: Using corrective malarplasty with tripod osteotomy, we achieved satisfactory results of zygoma expansion and improvement in orbital area. Therefore, malarplasty via tripod osteotomy cannot be applied only on the patients with traumatic zygoma deformation, but also on the patients with nontraumatic facial asymmetry.


Assuntos
Povo Asiático , Enoftalmia/cirurgia , Assimetria Facial/cirurgia , Osteotomia/métodos , Zigoma/cirurgia , Adolescente , Placas Ósseas , Transplante Ósseo , Enoftalmia/diagnóstico por imagem , Enoftalmia/etiologia , Assimetria Facial/diagnóstico por imagem , Assimetria Facial/etiologia , Feminino , Humanos , Masculino , Reoperação , República da Coreia , Tomografia Computadorizada por Raios X , Resultado do Tratamento , Zigoma/diagnóstico por imagem
10.
J Craniofac Surg ; 23(3): e238-41, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22627444

RESUMO

PURPOSE: Transvenous embolization has become the treatment of choice for carotid cavernous sinus fistula (CCSF). We report a case of coil embolization of CCSF using a superior ophthalmic vein (SOV) approach. METHODS: We have used the SOV approach on 5 patients with dural arteriovenous fistulas involving the cavernous sinus. Diagnostic facial contrast-enhanced computed tomography, brain magnetic resonance imaging, and contrast angiography and cerebral angiography revealed a CCSF. Fistula occlusion using an external SOV approach of CCSF was performed. RESULTS: Angiography performed on both sides demonstrated complete occlusion of the fistula. We had good result with coil embolization via SOV approach. We have a 100% success rate with no major complication. CONCLUSIONS: The coil embolization via SOV approach is a safe and effective treatment. The SOV can be channeled by allowing the insertion of detachable coils in the fistula. We suggest that there is need to training plastic surgeon to be experienced.


Assuntos
Fístula Carótido-Cavernosa/terapia , Embolização Terapêutica/métodos , Idoso , Fístula Carótido-Cavernosa/diagnóstico , Estética , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Tomografia Computadorizada por Raios X , Resultado do Tratamento
11.
Disabil Health J ; 3(3): 133-45, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20628583

RESUMO

BACKGROUND: Persons living with the effects of chronic and disabling conditions are often at increased risk for the development of secondary conditions and disabilities that can lead to further decline in health status, independence, functional status, life satisfaction, and overall quality of life. OBJECTIVE: The purpose of this study was to review the evidence for the benefits of wellness/health promotion interventions for persons with chronic and disabling conditions. METHODS: The authors conducted a Medline search (1990-2007) using terms related to wellness and health promotion cross-referenced with general terms for chronic and disabling conditions, as well as 15 specific chronic and/or disabling conditions (e.g., multiple sclerosis, spinal cord injury). Selection of studies was limited to those published in English that reported randomized controlled trails or prospective studies that involved adult human subjects with a chronic and/or disabling condition. All selected studies focused on some aspect of a wellness or health promotion intervention and involved a comparison or control group. Of the 5,847 studies initially identified in the search using medical subject heading terms, 190 met the criteria for full review. Data were extracted from these publications and summarized using descriptive statistics. RESULTS: Almost all studies (95%) explored the effects of wellness intervention in a sample diagnosed with a single condition (e.g., cancer, stroke, arthritis). Although the mean sample size was 100, the range in sample size varied widely (6-688); 25% of the studies had sample of 30 or fewer. Almost all studies (89.5%) reported positive effects of the wellness intervention, although the delivery and content of interventions as well as the measurement of outcomes, varied greatly. CONCLUSIONS: Our findings support an immediate post-intervention positive impact of wellness interventions across persons with a wide variety of chronic and disabling conditions. Future research that clearly specifies primary study outcomes and follows the CONSORT guidelines will strengthen future reviews of the evidence and facilitate application of the evidence of practice.


Assuntos
Pessoas com Deficiência/reabilitação , Promoção da Saúde/métodos , Resultado do Tratamento , Atividades Cotidianas , Adaptação Psicológica , Adulto , Idoso , Doença Crônica/reabilitação , Avaliação da Deficiência , Feminino , Nível de Saúde , Humanos , Masculino , Pessoa de Meia-Idade , Qualidade de Vida/psicologia , Marketing Social
12.
Environ Monit Assess ; 129(1-3): 87-95, 2007 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-17057947

RESUMO

We constructed an efficient and reliable yeast two-hybrid detection system to evaluate the estrogenic activity of endocrine disruptors (EDs) (Lee et al., Journal of Biochemistry, 131, 2002). This system employs the interaction between the human estrogen receptor beta (hERbeta) ligand binding domain and the co-activator SRC1. The extent of transcriptional activation by those chemicals correlated with estrogenic activities as measured by other assay systems. We applied this assay system to evaluate anti-estrogenic activities and found that known antagonistic compounds, 4-hydroxytamoxifen (OHT) and ICI 182,780, effectively inhibited reporter gene induction by 17beta-estradiol. We then tested the estrogenic and anti-estrogenic activities of polycyclic aromatic hydrocarbons (PAHs) using this assay system. PAHs only weakly induced the lacZ reporter gene at higher concentrations, but clearly showed an inhibitory effect on reporter gene induction by 10(-9) M 17beta-estradiol. These results suggest that PAHs are potentially anti-estrogenic and that the employed yeast detection system could be applicable to primary screening for effectors on estrogen receptor functions.


Assuntos
Disruptores Endócrinos/farmacologia , Receptor beta de Estrogênio/antagonistas & inibidores , Hidrocarbonetos Policíclicos Aromáticos/farmacologia , Técnicas do Sistema de Duplo-Híbrido , Microbiologia da Água , Disruptores Endócrinos/metabolismo , Receptor beta de Estrogênio/metabolismo , Coreia (Geográfico)
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