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1.
J Hazard Mater ; 406: 124314, 2021 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-33168312

RESUMO

The monitoring and removal of abundant heavy metals such as Cu ions are considerable global concerns because of their severe impact on the health of humans and other living organisms. To meet this global challenge, we engineered a novel mesoscopic capture protocol for the highly selective removal and visual monitoring of copper (Cu2+) ions from wide-ranging water sources. The capture hierarchy carriers featured three-dimensional, microsized MgO mesoarchitecture rectangular sheet-like mosaics that were randomly built in horizontal and vertical directions, uniformly arranged sheet faces, corners, and edges, smoothly quadrilateral surface coverage for strong Cu2+-to-ligand binding exposure, and multidiffusible pathways. The Cu2+ ion-selectively active captor surface design was engineered through the simple incorporation/encapsulation of a synthetic molecular chelation agent into hierarchical mesoporous MgO rectangular sheet platforms to produce a selective, visual mesoscopic captor (VMC). The nanoscale VMC dressing of MgO rectangular mosaic hierarchy by molecularly electron-enriched chelates with actively double core bindings of azo- and sulfonamide- groups and hydrophobic dodecyl tail showed potential to selectively trap and efficiently remove ultratrace Cu2+-ions with an extreme removal capability of ~233 mg/g from watery solutions, such as drinking water, hospital effluent, and food-processing wastewater at specific pH values. In addition to the Cu2+ ion-selective removal, the VMC design enabled the continuous visual monitoring of ultratrace Cu2+ ions (~3.35 × 10-8 M) as a consequence of strong chelate-to-Cu2+ binding events among all accumulated matrices in water sources. Our experimental recycle protocol provided evidence of reusability and recyclability of VMC (≥10 cycles). With our mesoscopic capture protocol, the VMC can be a promising candidate for the selective decontamination/removal and sensitive detection of hazardous inorganic pollutants from different water sources with indoor or outdoor applications.


Assuntos
Cobre , Poluentes Químicos da Água , Adsorção , Humanos , Concentração de Íons de Hidrogênio , Íons , Águas Residuárias , Poluentes Químicos da Água/análise
2.
Mater Today Bio ; 5: 100044, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32181446

RESUMO

Early detection and easy continuous monitoring of emerging or re-emerging infectious, contagious or other diseases are of particular interest for controlling healthcare advances and developing effective medical treatments to reduce the high global cost burden of diseases in the backdrop of lack of awareness regarding advancing diseases. Under an ever-increasing demand for biosensor design reliability for early stage recognition of infectious agents or contagious diseases and potential proteins, nanoscale manufacturing designs had developed effective nanodynamic sensing assays and compact wearable devices. Dynamic developments of biosensor technology are also vital to detect and monitor advanced diseases, such as human immunodeficiency virus (HIV), hepatitis B virus (HBV), hepatitis C virus (HCV), diabetes, cancers, liver diseases, cardiovascular diseases (CVDs), tuberculosis, and central nervous system (CNS) disorders. In particular, nanoscale biosensor designs have indispensable contribution to improvement of health concerns by early detection of disease, monitoring ecological and therapeutic agents, and maintaining high safety level in food and cosmetics. This review reports an overview of biosensor designs and their feasibility for early investigation, detection, and quantitative determination of many advanced diseases. Biosensor strategies are highlighted to demonstrate the influence of nanocompact and lightweight designs on accurate analyses and inexpensive sensing assays. To date, the effective and foremost developments in various nanodynamic designs associated with simple analytical facilities and procedures remain challenging. Given the wide evolution of biosensor market requirements and the growing demand in the creation of early stage and real-time monitoring assays, precise output signals, and easy-to-wear and self-regulating analyses of diseases, innovations in biosensor designs based on novel fabrication of nanostructured platforms with active surface functionalities would produce â€‹remarkable biosensor devices. This review offers evidence for researchers and inventors to focus on biosensor challenge and improve fabrication of nanobiosensors to revolutionize consumer and healthcare markets.

3.
Nanoscale Adv ; 2(8): 3525-3541, 2020 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-36134271

RESUMO

We report on the key influence of mesoscopic super-open-eye core-shell spheroids of TiO2- and LiFePO4-wrapped nanocarbon carved anode/cathode electrodes with uniform interior accommodation/storage pockets for the creation of fully reversible and dynamic Li-ion power battery (LIB) models. The mesoscopic core-shell anode/cathode electrodes provide potential half- and full-cell LIB-CR2032 configuration designs, and large-scale pouch models. In these variable mesoscopic LIB models, the broad-free-access and large-open-eye like gate-in-transport surfaces featured electrodes are key factors of built-in LIBs with excellent charge/discharge capacity, energy density performances, and outstanding cycling stability. Mesoscopic open-eye spheroid full-LIB-CR2032 configuration models retain 77.8% of the 1st cycle discharge specific capacity of 168.68 mA h g-1 after multiple cycling (i.e., 1st to 2000th cycles), efficient coulombic performance of approximately 99.6% at 0.1C, and high specific energy density battery of approximately 165.66 W h kg-1 at 0.1C. Furthermore, we have built a dynamic, super-open-mesoeye pouch LIB model using dense packing sets that are technically significant to meet the tradeoff requirements and long-term driving range of electric vehicles (EVs). The full-pouch package LIB models retain a powerful gate-in-transport system for heavy loaded electron/Li+ ion storage, diffusion, and truck movement through open-ended out/in and then up/downward eye circular/curvy folds, thereby leading to substantial durability, and remarkable electrochemical performances even after long-life charge/discharge cycling.

4.
Sci Rep ; 9(1): 14701, 2019 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-31605015

RESUMO

Modulation of lithium-ion battery (LIB) anodes/cathodes with three-dimensional (3D) topographical hierarchy ridges, surface interfaces, and vortices promotes the power tendency of LIBs in terms of high-energy density and power density. Large-scale meso-geodesics offer a diverse range of spatial LIB models along the geodetically shaped downward/upward curvature, leading to open-ended movement gate options, and diffusible space orientations. Along with the primary 3D super-scalable hierarchy, the formation of structural features of building block egress/ingress, curvature cargo-like sphere vehicles, irregularly located serrated cuticles with abundant V-undulated rigidness, feathery tube pipe conifers, and a band of dagger-shaped needle sticks on anode/cathode electrode surfaces provides high performance LIB modules. The geodetically-shaped anode/cathode design enables the uniqueness of all LIB module configurations in terms of powerful lithium ion (Li+) movement revolving in out-/in- and up-/downward diffusion regimes and in hovering electron density for high-speed discharge rates. The stability of built-in anode//cathode full-scale LIB-model meso-geodesics affords an outstanding long-term cycling performance. The full-cell LIB meso-geodesics offered 91.5% retention of the first discharge capacity of 165.8 mAhg-1 after 2000 cycles, Coulombic efficiency of ~99.6% at the rate of 1 C and room temperature, and high specific energy density of ≈119 Wh kg-1. This LIB meso-geodesic module configuration may align perfectly with the requirements of the energy density limit mandatory for long-term EV driving range and the scale-up commercial manufactures.

5.
Nanomicro Lett ; 11(1): 84, 2019 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-34138059

RESUMO

To control the power hierarchy design of lithium-ion battery (LIB) built-up sets for electric vehicles (EVs), we offer intensive theoretical and experimental sets of choice anode/cathode architectonics that can be modulated in full-scale LIB built-up models. As primary structural tectonics, heterogeneous composite superstructures of full-cell-LIB (anode//cathode) electrodes were designed in closely packed flower agave rosettes TiO2@C (FRTO@C anode) and vertical-star-tower LiFePO4@C (VST@C cathode) building blocks to regulate the electron/ion movement in the three-dimensional axes and orientation pathways. The superpower hierarchy surfaces and multi-directional orientation components may create isosurface potential electrodes with mobile electron movements, in-to-out interplay electron dominances, and electron/charge cloud distributions. This study is the first to evaluate the hotkeys of choice anode/cathode architectonics to assemble different LIB-electrode platforms with high-mobility electron/ion flows and high-performance capacity functionalities. Density functional theory calculation revealed that the FRTO@C anode and VST-(i)@C cathode architectonics are a superior choice for the configuration of full-scale LIB built-up models. The integrated FRTO@C//VST-(i)@C full-scale LIB retains a huge discharge capacity (~ 94.2%), an average Coulombic efficiency of 99.85% after 2000 cycles at 1 C, and a high energy density of 127 Wh kg-1, thereby satisfying scale-up commercial EV requirements.

6.
Sci Rep ; 8(1): 3740, 2018 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-29487302

RESUMO

We provide strong evidence of the effectiveness of homogenously self-propelled particle-in-particle diffusion, interaction and growth protocol. This technique was used for one-pot synthesis of novel nitrogen-graphene oxide (N-GO)/Co3O4 nanocrystals with cuboid rectangular prism-shaped nanorods (NRs) along {110}-plane and truncated polyhedrons with densely-exposed, multi-facet sites along {311} and {111} planes. These hierarchal nanocrystals create electrode catalyst patterns with vast-range accessibility to active Co2+ sites, a vascular system for the transport and retention of captured O2 molecule interiorly, and low adsorption energy and dense electron configuration surfaces during the oxygen reduction reaction (ORR). The superior electrocatalytic ORR activity of the N-GO/Co3O4 polyhedron nanocrystals in terms of electrochemical selectivity, durability and stability compared with NRs or commercial Pt/C catalysts confirms the synergetic contribution of multi-functional, dense-exposed, and actively topographic facets of polyhedrons to significantly activate the catalytic nature of the catalyst. Our findings show real evidence, for the first time that not only the large number of catalytically active Co2+ cations at the top surface layer but also the dense location of active Co2+ sites on the upper-zone top-on-plane exposure, and the electron density configuration and distribution around the Co2+ sites were important for effective ORR.

7.
J Hazard Mater ; 260: 833-43, 2013 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-23856314

RESUMO

Here, we designed novel optical sensor based on the wormhole hexagonal mesoporous core/multi-shell silica nanoparticles that enabled the selective recognition and removal of these extremely toxic metals from drinking water. The surface-coating process of a mesoporous core/double-shell silica platforms by several consequence decorations using a cationic surfactant with double alkyl tails (CS-DAT) and then a synthesized dicarboxylate 1,5-diphenyl-3-thiocarbazone (III) signaling probe enabled us to create a unique hierarchical multi-shell sensor. In this design, the high loading capacity and wrapping of the CS-DAT and III organic moieties could be achieved, leading to the formation of silica core with multi-shells that formed from double-silica, CS-DAT, and III dressing layers. In this sensing system, notable changes in color and reflectance intensity of the multi-shelled sensor for Cu(2+), Co(2+), Cd(2+), and Hg(2+) ions, were observed at pH 2, 8, 9.5 and 11.5, respectively. The multi-shelled sensor is added to enable accessibility for continuous monitoring of several different toxic metal ions and efficient multi-ion sensing and removal capabilities with respect to reversibility, selectivity, and signal stability.


Assuntos
Íons/análise , Metais/análise , Dispositivos Ópticos , Poluentes Químicos da Água/análise , Purificação da Água/métodos , Cádmio/química , Cobalto/química , Cobre/química , Água Potável , Concentração de Íons de Hidrogênio , Cinética , Mercúrio/química , Nanopartículas/química , Óptica e Fotônica , Reprodutibilidade dos Testes , Dióxido de Silício/química , Propriedades de Superfície , Temperatura , Poluentes Químicos da Água/química , Abastecimento de Água
8.
Adv Healthc Mater ; 2(6): 854-62, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23307510

RESUMO

Because toxic heavy metals tend to bioaccumulate, they represent a substantial human health hazard. Various methods are used to identify and quantify toxic metals in biological tissues and environment fluids, but a simple, rapid, and inexpensive system has yet to be developed. To reduce the necessity for instrument-dependent analysis, we developed a single, pH-dependent, nanosphere (NS) sensor for naked-eye detection and removal of toxic metal ions from drinking water and physiological systems (i.e., blood). The design platform for the optical NS sensor is composed of double mesoporous core-shell silica NSs fabricated by one-pot, template-guided synthesis with anionic surfactant. The dense shell-by-shell NS construction generated a unique hierarchical NS sensor with a hollow cage interior to enable accessibility for continuous monitoring of several different toxic metal ions and efficient multi-ion sensing and removal capabilities with respect to reversibility, longevity, selectivity, and signal stability. Here, we examined the application of the NS sensor for the removal of toxic metals (e.g., lead ions from a physiological system, such as human blood). The findings show that this sensor design has potential for the rapid screening of blood lead levels so that the effects of lead toxicity can be avoided.


Assuntos
Remoção de Componentes Sanguíneos/métodos , Metais Pesados/sangue , Metais Pesados/isolamento & purificação , Nanosferas/química , Refratometria/métodos , Silício/química , Ultrafiltração/métodos , Intoxicação por Metais Pesados , Humanos , Dispositivos Ópticos , Intoxicação/sangue , Intoxicação/prevenção & controle , Transdutores
9.
J Dent ; 41(4): 287-96, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23207518

RESUMO

OBJECTIVES: To determine the effect of temperature, over a clinically relevant range, on the creep behaviour of a set of conventional and flowable resin-composites including two subgroups having the same resin matrix and varied filler loading. METHODS: Eight dental resin-composites: four flowable and four conventional were investigated. Stainless steel split moulds (4 mm × 6 mm) were used to prepare cylindrical specimens for creep examination. Specimens were irradiated in the moulds in layers of 2mm thickness (40s each), as well as from the radial direction after removal from the moulds, using a light-curing unit with irradiance of 650 mW/cm(2). A total of 15 specimens from each material were prepared and divided into three groups (n=5) according to the temperature; Group I: (23°C), Group II: (37°C) and Group III: (45°C). Each specimen was loaded (20 MPa) for 2h and unloaded for 2h. Creep was measured continuously over the loading and unloading periods. RESULTS: At higher temperatures greater creep and permanent set were recorded. The lowest mean creep occurred with GS and GH resin-composites. Percentage of creep recovery decreased at higher temperatures. At 23°C, the materials exhibited comparable creep. At 37°C and 45°C, however, there was a greater variation between materials. For all resin-composites, there was a strong linear correlation with temperature for both creep and permanent set. CONCLUSIONS: Creep parameters of resin-composites are sensitive to temperature increase from 23 to 45°C, as can occur intra-orally. For a given resin matrix, creep decreased with higher filler loading.


Assuntos
Resinas Compostas/química , Análise de Variância , Análise do Estresse Dentário , Temperatura Alta , Modelos Lineares , Teste de Materiais , Viscosidade
10.
Dent Mater ; 28(12): 1292-300, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23031485

RESUMO

OBJECTIVE: To determine by nanoindentation the hardness and elastic modulus of resin-composites, including a series with systematically varied filler loading, plus other representative materials that fall into the categories of flowable, bulk-fill and conventional nano-hybrid types. METHODS: Ten dental resin-composites: three flowable, three bulk-fill and four conventional were investigated using nanoindentation. Disc specimens (15mm×2mm) were prepared from each material using a metallic mold. Specimens were irradiated in the mold at top and bottom surfaces in multiple overlapping points (40s each) with light curing unit at 650mW/cm(2). Specimens were then mounted in 3cm diameter phenolic ring forms and embedded in a self-curing polystyrene resin. After grinding and polishing, specimens were stored in distilled water at 37°C for 7 days. Specimens were investigated using an Agilent Technologies XP nanoindenter equipped with a Berkovich diamond tip (100nm radius). Each specimen was loaded at one loading rate and three different unloading rates (at room temperature) with thirty indentations, per unloading rate. The maximum load applied by the nanoindenter to examine the specimens was 10mN. RESULTS: Dependent on the type of the resin-composite material, the mean values ranged from 0.73GPa to 1.60GPa for nanohardness and from 14.44GPa to 24.07GPa for elastic modulus. There was a significant positive non-linear correlation between elastic modulus and nanohardness (r(2)=0.88). Nonlinear regression revealed a significant positive correlation (r(2)=0.62) between elastic moduli and filler loading and a non-significant correlation (r(2)=0.50) between nanohardness and filler loading of the studied materials. Varying the unloading rates showed no consistent effect on the elastic modulus and nanohardness of the studied materials. SIGNIFICANCE: For a specific resin matrix, both elastic moduli and nanohardness correlated positively with filler loading. For the resin-composites investigated, the group-average elastic moduli and nanohardnesses for bulk-fill and flowable materials were lower than those for conventional nano-hybrid composites.


Assuntos
Resinas Compostas/química , Materiais Dentários/química , Nanocompostos/química , Resinas Compostas/efeitos da radiação , Lâmpadas de Polimerização Dentária , Materiais Dentários/efeitos da radiação , Polimento Dentário , Análise do Estresse Dentário/instrumentação , Diamante/química , Módulo de Elasticidade , Dureza , Humanos , Teste de Materiais , Nanocompostos/efeitos da radiação , Nanotecnologia/instrumentação , Polimerização , Doses de Radiação , Propriedades de Superfície , Temperatura , Fatores de Tempo , Água/química
11.
Dent Mater ; 28(11): 1171-82, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22999374

RESUMO

OBJECTIVES: To evaluate nanoindentation as an experimental tool for characterizing the viscoelastic time-dependent creep of resin-composites and to compare the resulting parameters with those obtained by bulk compressive creep. METHODS: Ten dental resin-composites: five conventional, three bulk-fill and two flowable were investigated using both nanoindentation creep and bulk compressive creep methods. For nano creep, disc specimens (15mm×2mm) were prepared from each material by first injecting the resin-composite paste into metallic molds. Specimens were irradiated from top and bottom surfaces in multiple overlapping points to ensure optimal polymerization using a visible light curing unit with output irradiance of 650mW/cm(2). Specimens then were mounted in 3cm diameter phenolic ring forms and embedded in a self-curing polystyrene resin. Following grinding and polishing, specimens were stored in distilled water at 37°C for 24h. Using an Agilent Technologies XP nanoindenter equipped with a Berkovich diamond tip (100nm radius), the nano creep was measured at a maximum load of 10mN and the creep recovery was determined when each specimen was unloaded to 1mN. For bulk compressive creep, stainless steel split molds (4mm×6mm) were used to prepare cylindrical specimens which were thoroughly irradiated at 650mW/cm(2) from multiple directions and stored in distilled water at 37°C for 24h. Specimens were loaded (20MPa) for 2h and unloaded for 2h. One-way ANOVA, Levene's test for homogeneity of variance and the Bonferroni post hoc test (all at p≤0.05), plus regression plots, were used for statistical analysis. RESULTS: Dependent on the type of resin-composite material and the loading/unloading parameters, nanoindentation creep ranged from 29.58nm to 90.99nm and permanent set ranged from 8.96nm to 30.65nm. Bulk compressive creep ranged from 0.47% to 1.24% and permanent set ranged from 0.09% to 0.38%. There was a significant (p=0.001) strong positive non-linear correlation (r(2)=0.97) between bulk creep and nano creep that could also be expressed via a simple fractional-power function. A significant (p=0.003) positive linear correlation (r(2)=0.69) existed between nano creep recovery and bulk creep recovery. With both methods of examination, except for Venus Bulk Fill™ (VB), the flowable and bulk-fill resin-composites exhibited creep within the range exhibited by the conventional resin-composites. SIGNIFICANCE: Despite the differences in loading and unloading conditions, in both methods of examination the correlation observed between the creep and recovery responses for a set of resin-composites was high. Both nano creep and recovery positively correlated with loading and unloading rates, respectively.


Assuntos
Resinas Compostas/química , Análise do Estresse Dentário/métodos , Testes de Dureza , Teste de Materiais/métodos , Nanocompostos/química , Estresse Mecânico , Elasticidade , Cura Luminosa de Adesivos Dentários , Estrutura Molecular , Movimento , Polimerização , Fatores de Tempo , Viscosidade
12.
Dent Mater ; 28(8): 928-35, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22656273

RESUMO

OBJECTIVES: To determine the creep deformation of several "bulk-fill" resin-composite formulations in comparison with some other types. METHODS: Six resin-composites; four bulk-fill and two conventional were investigated. Stainless steel split molds (4 mm × 6 mm) were used to prepare cylindrical specimens for creep testing. Specimens were thoroughly irradiated with 650 mW cm(-2). A total of 10 specimens for each material were divided into two groups (n = 5) according to the storage condition; Group A stored dry at 37 °C for 24h and Group B stored in distilled water at 37 °C in an incubator for 24h. Each specimen was loaded (20 MPa) for 2h and unloaded for 2h. The strain deformation was recorded continuously for 4h. Statistical analysis was performed using a two-way ANOVA followed by one-way ANOVA and the Bonferroni post hoc test at a significance level of a = 0.05. RESULTS: The maximum creep strain % ranged from 0.72% up to 1.55% for Group A and the range for Group B increased from 0.79% up to 1.80% due to water sorption. Also, the permanent set ranged from 0.14% up to 0.47% for Group A and from 0.20% up to 0.59% for Group B. Dependent on the material and storage condition, the percentage of creep strain recovery ranged between 64% and 81%. Increased filler loading in the bulk-fill materials decreased the creep strain magnitude. SIGNIFICANCE: Creep deformation of all studied resin-composites increased with wet storage. The "bulk-fill" composites exhibited an acceptable creep deformation and within the range exhibited by other resin-composites.


Assuntos
Resinas Compostas , Restauração Dentária Permanente , Resinas Compostas/química , Falha de Restauração Dentária , Restauração Dentária Permanente/métodos , Análise do Estresse Dentário , Armazenamento de Medicamentos , Teste de Materiais/instrumentação , Teste de Materiais/métodos , Processamento de Sinais Assistido por Computador , Estresse Mecânico , Viscosidade , Água
13.
J Colloid Interface Sci ; 260(1): 184-94, 2003 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-12742049

RESUMO

The sorption of phenol, and o-, m-, and p-aminophenol (o-, m-, and p-AP) onto highly ordered mesoporous silicas (HOM) with cubic Im3m (HOM-1), hexagonal H(I) (HOM-2), 3-D hexagonal p6(3)/mmc (HOM-3), cubic Ia3d (HOM-5), lamellar L( infinity ) (HOM-6), and solid phase S (HOM-8) materials has been investigated kinetically. Nanostructured silica molecular sieves have been prepared at 25 and 60 degrees C with lyotropic liquid-crystalline phases of the nonionic surfactant (Brij 76) that was used as a structure-directing agent. Such nanostructured silicas have been studied by 29Si nuclear magnetic resonance (29Si NMR), powder X-ray diffraction (XRD), the Brunauer-Emmett-Teller (BET) method for nitrogen adsorption and surface area measurements, and transmission electron microscopy (TEM) techniques after synthesis and sorption. It was found that all materials exhibit well-defined long-range porous architectures without significant loss of the ordered texture during phenol sorption. The kinetics of phenol sorption has been studied spectrophotometrically at different temperatures (25-40 degrees C; +/-0.1 range). The sorption rate is zero order in all phenols sorbed, and increases directly in the pattern P >m-AP > o-AP > p-AP, which reflects the mobility of the phenol compounds on the particle pores. The isothermal sorption and the kinetic parameters were discussed and it was established that a diffusion-controlled process characterizes phenol sorption. Furthermore, the mechanism of phenol sorption was deduced to be predominantly particle diffusion. The diffusion coefficients were determined using Fick's equation. The trend of diffusion of all phenols onto nanoporous silica was HOM-8 > HOM-2 > HOM-6 > HOM-5 > HOM-1 > HOM-3, reflecting the effect of the uniform pore size distribution and the internal surface area of the nanostructured silicas on the diffusion process.

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