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1.
Sci Rep ; 11(1): 15598, 2021 08 02.
Artigo em Inglês | MEDLINE | ID: mdl-34341363

RESUMO

Although some neurodegenerative diseases can be identified by behavioral characteristics relatively late in disease progression, we currently lack methods to predict who has developed disease before the onset of symptoms, when onset will occur, or the outcome of therapeutics. New biomarkers are needed. Here we describe spectral phenotyping, a new kind of biomarker that makes disease predictions based on chemical rather than biological endpoints in cells. Spectral phenotyping uses Fourier Transform Infrared (FTIR) spectromicroscopy to produce an absorbance signature as a rapid physiological indicator of disease state. FTIR spectromicroscopy has over the past been used in differential diagnoses of manifest disease. Here, we report that the unique FTIR chemical signature accurately predicts disease class in mouse with high probability in the absence of brain pathology. In human cells, the FTIR biomarker accurately predicts neurodegenerative disease class using fibroblasts as surrogate cells.

2.
Adv Mater ; 33(39): e2103000, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34397123

RESUMO

The competing and non-equilibrium phase transitions, involving dynamic tunability of cooperative electronic and magnetic states in strongly correlated materials, show great promise in quantum sensing and information technology. To date, the stabilization of transient states is still in the preliminary stage, particularly with respect to molecular electronic solids. Here, a dynamic and cooperative phase in potassium-7,7,8,8-tetracyanoquinodimethane (K-TCNQ) with the control of pulsed electromagnetic excitation is demonstrated. Simultaneous dynamic and coherent lattice perturbation with 8 ns pulsed laser (532 nm, 15 MW cm-2 , 10 Hz) in such a molecular electronic crystal initiates a stable long-lived (over 400 days) conducting paramagnetic state (≈42 Ωcm), showing the charge-spin bistability over a broad temperature range from 2 to 360 K. Comprehensive noise spectroscopy, in situ high-pressure measurements, electron spin resonance (ESR), theoretical model, and scanning tunneling microscopy/spectroscopy (STM/STS) studies provide further evidence that such a transition is cooperative, requiring a dedicated charge-spin-lattice decoupling to activate and subsequently stabilize nonequilibrium phase. The cooperativity triggered by ultrahigh-strain-rate (above 106 s- 1 ) pulsed excitation offers a collective control toward the generation and stabilization of strongly correlated electronic and magnetic orders in molecular electronic solids and offers unique electro-magnetic phases with technological promises.

3.
Nano Lett ; 19(3): 1982-1989, 2019 03 13.
Artigo em Inglês | MEDLINE | ID: mdl-30779587

RESUMO

Strain plays an important role in condensed matter physics and materials science because it can strongly modify the mechanical, electrical, and optical properties of a material and even induce a structural phase transition. Strain effects are especially interesting in atomically thin two-dimensional (2D) materials, where unusually large strain can be achieved without breaking them. Measuring the strain distribution in 2D materials at the nanometer scale is therefore greatly important but is extremely challenging experimentally. Here, we use near-field infrared nanoscopy to demonstrate phonon polariton-assisted mapping and quantitative analysis of strain in atomically thin polar crystals of hexagonal boron nitride (hBN) at the nanoscale. A local strain as low as 0.01% can be detected using this method with ∼20 nm spatial resolution. Such ultrasensitive nanoscale strain imaging and analysis technique opens up opportunities for exploring unique local strain structures and strain-related physics in 2D materials. In addition, experimental evidence for local strain-induced phonon polariton reflection is also provided, which offers a new approach to manipulate light at deep subwavelength scales for nanophotonic devices.

4.
Sci Adv ; 3(11): e1600735, 2017 11.
Artigo em Inglês | MEDLINE | ID: mdl-29202025

RESUMO

The ability to probe symmetry-breaking transitions on their natural time scales is one of the key challenges in nonequilibrium physics. Stripe ordering represents an intriguing type of broken symmetry, where complex interactions result in atomic-scale lines of charge and spin density. Although phonon anomalies and periodic distortions attest the importance of electron-phonon coupling in the formation of stripe phases, a direct time-domain view of vibrational symmetry breaking is lacking. We report experiments that track the transient multi-terahertz response of the model stripe compound La1.75Sr0.25NiO4, yielding novel insight into its electronic and structural dynamics following an ultrafast optical quench. We find that although electronic carriers are immediately delocalized, the crystal symmetry remains initially frozen-as witnessed by time-delayed suppression of zone-folded Ni-O bending modes acting as a fingerprint of lattice symmetry. Longitudinal and transverse vibrations react with different speeds, indicating a strong directionality and an important role of polar interactions. The hidden complexity of electronic and structural coupling during stripe melting and formation, captured here within a single terahertz spectrum, opens new paths to understanding symmetry-breaking dynamics in solids.

5.
Nat Commun ; 8(1): 2262, 2017 12 22.
Artigo em Inglês | MEDLINE | ID: mdl-29273808

RESUMO

Broadband tunability is a central theme in contemporary nanophotonics and metamaterials research. Combining metamaterials with phase change media offers a promising approach to achieve such tunability, which requires a comprehensive investigation of the electromagnetic responses of novel materials at subwavelength scales. In this work, we demonstrate an innovative way to tailor band-selective electromagnetic responses at the surface of a heavy fermion compound, samarium sulfide (SmS). By utilizing the intrinsic, pressure sensitive, and multi-band electron responses of SmS, we create a proof-of-principle heavy fermion metamaterial, which is fabricated and characterized using scanning near-field microscopes with <50 nm spatial resolution. The optical responses at the infrared and visible frequency ranges can be selectively and separately tuned via modifying the occupation of the 4f and 5d band electrons. The unique pressure, doping, and temperature tunability demonstrated represents a paradigm shift for nanoscale metamaterial and metasurface design.

6.
South Med J ; 110(6): 408-411, 2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-28575898

RESUMO

OBJECTIVES: This study evaluated the effectiveness of the Center for Executive Medicine (CEM) concierge primary care practice on preventive colorectal cancer (CRC) screening rates relative to local and national comparator data. METHODS: We performed an electronic medical record search encompassing our entire patient population who are between the ages of 50 and 75 years to determine the rate of CRC screening. We compared this rate with the average rate of Medicare Advantage plans reported by our Independent Physician Association (IPA) in 2015 and national health plans reported by the National Committee for Quality Assurance in 2014. RESULTS: The CEM had a CRC screening rate of 90.2%, which was significantly higher than local IPA Medicare Advantage plans (63.3%) and National Committee for Quality Assurance national plans (57.7%-66.5%). CEM members were significantly more likely than were IPA members to undergo screening (odds ratio 1.425, 95% confidence interval 1.348-1.507, P < 0.0001). CONCLUSIONS: These results suggest that the CEM practice strategy and processes increase CRC screening rates.


Assuntos
Neoplasias Colorretais/diagnóstico , Medicina Concierge , Detecção Precoce de Câncer/estatística & dados numéricos , Idoso , Registros Eletrônicos de Saúde , Feminino , Humanos , Cobertura do Seguro , Seguro Saúde , Masculino , Pessoa de Meia-Idade , Sangue Oculto
7.
Nature ; 541(7638): 511-515, 2017 01 26.
Artigo em Inglês | MEDLINE | ID: mdl-28068671

RESUMO

The critical role in surface reactions and heterogeneous catalysis of metal atoms with low coordination numbers, such as found at atomic steps and surface defects, is firmly established. But despite the growing availability of tools that enable detailed in situ characterization, so far it has not been possible to document this role directly. Surface properties can be mapped with high spatial resolution, and catalytic conversion can be tracked with a clear chemical signature; however, the combination of the two, which would enable high-spatial-resolution detection of reactions on catalytic surfaces, has rarely been achieved. Single-molecule fluorescence spectroscopy has been used to image and characterize single turnover sites at catalytic surfaces, but is restricted to reactions that generate highly fluorescing product molecules. Herein the chemical conversion of N-heterocyclic carbene molecules attached to catalytic particles is mapped using synchrotron-radiation-based infrared nanospectroscopy with a spatial resolution of 25 nanometres, which enabled particle regions that differ in reactivity to be distinguished. These observations demonstrate that, compared to the flat regions on top of the particles, the peripheries of the particles-which contain metal atoms with low coordination numbers-are more active in catalysing oxidation and reduction of chemically active groups in surface-anchored N-heterocyclic carbene molecules.

8.
Nat Commun ; 7: 13079, 2016 10 07.
Artigo em Inglês | MEDLINE | ID: mdl-27713412

RESUMO

Silk protein fibres produced by silkworms and spiders are renowned for their unparalleled mechanical strength and extensibility arising from their high-ß-sheet crystal contents as natural materials. Investigation of ß-sheet-oriented conformational transitions in silk proteins at the nanoscale remains a challenge using conventional imaging techniques given their limitations in chemical sensitivity or limited spatial resolution. Here, we report on electron-regulated nanoscale polymorphic transitions in silk proteins revealed by near-field infrared imaging and nano-spectroscopy at resolutions approaching the molecular level. The ability to locally probe nanoscale protein structural transitions combined with nanometre-precision electron-beam lithography offers us the capability to finely control the structure of silk proteins in two and three dimensions. Our work paves the way for unlocking essential nanoscopic protein structures and critical conditions for electron-induced conformational transitions, offering new rules to design protein-based nanoarchitectures.


Assuntos
Fibroínas/química , Fibroínas/ultraestrutura , Seda/química , Seda/ultraestrutura , Animais , Bombyx/metabolismo , Imageamento Tridimensional/métodos , Conformação Molecular , Espectroscopia de Infravermelho com Transformada de Fourier/métodos , Aranhas/metabolismo
9.
Nature ; 520(7549): 650-5, 2015 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-25901686

RESUMO

Electron valley, a degree of freedom that is analogous to spin, can lead to novel topological phases in bilayer graphene. A tunable bandgap can be induced in bilayer graphene by an external electric field, and such gapped bilayer graphene is predicted to be a topological insulating phase protected by no-valley mixing symmetry, featuring quantum valley Hall effects and chiral edge states. Observation of such chiral edge states, however, is challenging because inter-valley scattering is induced by atomic-scale defects at real bilayer graphene edges. Recent theoretical work has shown that domain walls between AB- and BA-stacked bilayer graphene can support protected chiral edge states of quantum valley Hall insulators. Here we report an experimental observation of ballistic (that is, with no scattering of electrons) conducting channels at bilayer graphene domain walls. We employ near-field infrared nanometre-scale microscopy (nanoscopy) to image in situ bilayer graphene layer-stacking domain walls on device substrates, and we fabricate dual-gated field effect transistors based on the domain walls. Unlike single-domain bilayer graphene, which shows gapped insulating behaviour under a vertical electrical field, bilayer graphene domain walls feature one-dimensional valley-polarized conducting channels with a ballistic length of about 400 nanometres at 4 kelvin. Such topologically protected one-dimensional chiral states at bilayer graphene domain walls open up opportunities for exploring unique topological phases and valley physics in graphene.

10.
Proc Natl Acad Sci U S A ; 111(20): 7191-6, 2014 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-24803431

RESUMO

Characterizing and ultimately controlling the heterogeneity underlying biomolecular functions, quantum behavior of complex matter, photonic materials, or catalysis requires large-scale spectroscopic imaging with simultaneous specificity to structure, phase, and chemical composition at nanometer spatial resolution. However, as with any ultrahigh spatial resolution microscopy technique, the associated demand for an increase in both spatial and spectral bandwidth often leads to a decrease in desired sensitivity. We overcome this limitation in infrared vibrational scattering-scanning probe near-field optical microscopy using synchrotron midinfrared radiation. Tip-enhanced localized light-matter interaction is induced by low-noise, broadband, and spatially coherent synchrotron light of high spectral irradiance, and the near-field signal is sensitively detected using heterodyne interferometric amplification. We achieve sub-40-nm spatially resolved, molecular, and phonon vibrational spectroscopic imaging, with rapid spectral acquisition, spanning the full midinfrared (700-5,000 cm(-1)) with few cm(-1) spectral resolution. We demonstrate the performance of synchrotron infrared nanospectroscopy on semiconductor, biomineral, and protein nanostructures, providing vibrational chemical imaging with subzeptomole sensitivity.


Assuntos
Microscopia/métodos , Nanotecnologia/métodos , Espectrofotometria Infravermelho/métodos , Elétrons , Análise de Fourier , Interferometria/métodos , Luz , Microscopia de Força Atômica/métodos , Nanotecnologia/instrumentação , Fônons , Reprodutibilidade dos Testes , Semicondutores , Processamento de Sinais Assistido por Computador , Dióxido de Silício/química , Espectrofotometria Infravermelho/instrumentação , Propriedades de Superfície , Síncrotrons , Vibração
11.
Proc Natl Acad Sci U S A ; 111(17): 6198-202, 2014 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-24733906

RESUMO

Semiconductor heterostructures are the fundamental platform for many important device applications such as lasers, light-emitting diodes, solar cells, and high-electron-mobility transistors. Analogous to traditional heterostructures, layered transition metal dichalcogenide heterostructures can be designed and built by assembling individual single layers into functional multilayer structures, but in principle with atomically sharp interfaces, no interdiffusion of atoms, digitally controlled layered components, and no lattice parameter constraints. Nonetheless, the optoelectronic behavior of this new type of van der Waals (vdW) semiconductor heterostructure is unknown at the single-layer limit. Specifically, it is experimentally unknown whether the optical transitions will be spatially direct or indirect in such hetero-bilayers. Here, we investigate artificial semiconductor heterostructures built from single-layer WSe2 and MoS2. We observe a large Stokes-like shift of ∼ 100 meV between the photoluminescence peak and the lowest absorption peak that is consistent with a type II band alignment having spatially direct absorption but spatially indirect emission. Notably, the photoluminescence intensity of this spatially indirect transition is strong, suggesting strong interlayer coupling of charge carriers. This coupling at the hetero-interface can be readily tuned by inserting dielectric layers into the vdW gap, consisting of hexagonal BN. Consequently, the generic nature of this interlayer coupling provides a new degree of freedom in band engineering and is expected to yield a new family of semiconductor heterostructures having tunable optoelectronic properties with customized composite layers.

12.
J Am Chem Soc ; 136(9): 3624-9, 2014 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-24498978

RESUMO

Analysis of catalytic organic transformations in flow reactors and detection of short-lived intermediates are essential for optimization of these complex reactions. In this study, spectral mapping of a multistep catalytic reaction in a flow microreactor was performed with a spatial resolution of 15 µm, employing micrometer-sized synchrotron-based IR and X-ray beams. Two nanometer sized Au nanoclusters were supported on mesoporous SiO2, packed in a flow microreactor, and activated toward the cascade reaction of pyran formation. High catalytic conversion and tunable products selectivity were achieved under continuous flow conditions. In situ synchrotron-sourced IR microspectroscopy detected the evolution of the reactant, vinyl ether, into the primary product, allenic aldehyde, which then catalytically transformed into acetal, the secondary product. By tuning the residence time of the reactants in a flow microreactor a detailed analysis of the reaction kinetics was performed. An in situ micrometer X-ray absorption spectroscopy scan along the flow reactor correlated locally enhanced catalytic conversion, as detected by IR microspectroscopy, to areas with high concentration of Au(III), the catalytically active species. These results demonstrate the fundamental understanding of the mechanism of catalytic reactions which can be achieved by the detailed mapping of organic transformations in flow reactors.

13.
Proc Natl Acad Sci U S A ; 111(5): 1732-5, 2014 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-24449869

RESUMO

The solar wind (SW), composed of predominantly ∼1-keV H(+) ions, produces amorphous rims up to ∼150 nm thick on the surfaces of minerals exposed in space. Silicates with amorphous rims are observed on interplanetary dust particles and on lunar and asteroid soil regolith grains. Implanted H(+) may react with oxygen in the minerals to form trace amounts of hydroxyl (-OH) and/or water (H2O). Previous studies have detected hydroxyl in lunar soils, but its chemical state, physical location in the soils, and source(s) are debated. If -OH or H2O is generated in rims on silicate grains, there are important implications for the origins of water in the solar system and other astrophysical environments. By exploiting the high spatial resolution of transmission electron microscopy and valence electron energy-loss spectroscopy, we detect water sealed in vesicles within amorphous rims produced by SW irradiation of silicate mineral grains on the exterior surfaces of interplanetary dust particles. Our findings establish that water is a byproduct of SW space weathering. We conclude, on the basis of the pervasiveness of the SW and silicate materials, that the production of radiolytic SW water on airless bodies is a ubiquitous process throughout the solar system.

14.
Opt Express ; 21(14): 17150-60, 2013 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-23938562

RESUMO

Optical metamaterials have unique properties which result from geometric confinement of the optical conductivity. We developed a series of infrared metasurfaces based on an array of metallic square loop antennas. The far-field absorption spectrum can be designed with resonances across the infrared by scaling the geometric dimensions. We measure the amplitude and phase of the resonant mode as standing wave patterns within the square loops using scattering-scanning near-field optical microscopy (s-SNOM). Further, using a broad-band synchrotron-based FTIR microscope and s-SNOM at the Advanced Light Source, we are able to correlate far-field spectra to near-field modes of the metasurface as the resonance is tuned between samples. The results highlight the importance of multi-modal imaging for the design and characterization of optical metamaterials.


Assuntos
Iluminação/métodos , Teste de Materiais/métodos , Metais/química , Microscopia/métodos , Espectrofotometria Infravermelho/métodos , Propriedades de Superfície
15.
Nat Methods ; 10(9): 861-4, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23913258

RESUMO

We report Fourier transform infrared spectro-microtomography, a nondestructive three-dimensional imaging approach that reveals the distribution of distinctive chemical compositions throughout an intact biological or materials sample. The method combines mid-infrared absorption contrast with computed tomographic data acquisition and reconstruction to enhance chemical and morphological localization by determining a complete infrared spectrum for every voxel (millions of spectra determined per sample).


Assuntos
Processamento de Imagem Assistida por Computador/métodos , Espectroscopia de Infravermelho com Transformada de Fourier/métodos , Microtomografia por Raio-X/métodos , Animais , Células-Tronco Embrionárias/ultraestrutura , Cabelo/ultraestrutura , Humanos , Imageamento Tridimensional , Camundongos , Populus/ultraestrutura , Síncrotrons , Madeira/ultraestrutura
16.
Proc Natl Acad Sci U S A ; 110(29): 11688-91, 2013 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-23818622

RESUMO

The optical absorption properties of free-standing InAs nanomembranes of thicknesses ranging from 3 nm to 19 nm are investigated by Fourier transform infrared spectroscopy. Stepwise absorption at room temperature is observed, arising from the interband transitions between the subbands of 2D InAs nanomembranes. Interestingly, the absorptance associated with each step is measured to be ∼1.6%, independent of thickness of the membranes. The experimental results are consistent with the theoretically predicted absorptance quantum, AQ = πα/nc for each set of interband transitions in a 2D semiconductor, where α is the fine structure constant and nc is an optical local field correction factor. Absorptance quantization appears to be universal in 2D systems including III-V quantum wells and graphene.


Assuntos
Arsenicais/química , Índio/química , Luz , Nanoestruturas/química , Semicondutores , Absorção , Modelos Químicos , Teoria Quântica , Espectroscopia de Infravermelho com Transformada de Fourier
17.
Anal Chem ; 84(9): 4118-25, 2012 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-22468902

RESUMO

Protein phosphorylation is a post-translational modification that is essential for the regulation of many important cellular activities, including proliferation and differentiation. Current techniques for detecting protein phosphorylation in single cells often involve the use of fluorescence markers, such as antibodies or genetically expressed proteins. In contrast, infrared spectroscopy is a label-free and noninvasive analytical technique that can monitor the intrinsic vibrational signatures of chemical bonds. Here, we provide direct evidence that protein phosphorylation in individual living mammalian cells can be measured with synchrotron radiation-based Fourier transform-infrared (SR-FT-IR) spectromicroscopy. We show that PC12 cells stimulated with nerve growth factor (NGF) exhibit statistically significant temporal variations in specific spectral features, correlating with changes in protein phosphorylation levels and the subsequent development of neuron-like phenotypes in the cells. The spectral phosphorylation markers were confirmed by bimodal (FT-IR/fluorescence) imaging of fluorescently marked PC12 cells with sustained protein phosphorylation activity. Our results open up new possibilities for the label-free real-time monitoring of protein phosphorylation inside cells. Furthermore, the multimolecule sensitivity of this technique will be useful for unraveling the associated molecular changes during cellular signaling and response processes.


Assuntos
Neurônios/citologia , Proteínas/metabolismo , Espectroscopia de Infravermelho com Transformada de Fourier/instrumentação , Animais , Diferenciação Celular , Sobrevivência Celular , Fatores de Crescimento Neural/metabolismo , Neurônios/metabolismo , Células PC12 , Fosforilação , Ratos , Sensibilidade e Especificidade , Síncrotrons/instrumentação
18.
Proc Natl Acad Sci U S A ; 109(16): 6088-93, 2012 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-22492931

RESUMO

Crystalline biominerals do not resemble faceted crystals. Current explanations for this property involve formation via amorphous phases. Using X-ray absorption near-edge structure (XANES) spectroscopy and photoelectron emission microscopy (PEEM), here we examine forming spicules in embryos of Strongylocentrotus purpuratus sea urchins, and observe a sequence of three mineral phases: hydrated amorphous calcium carbonate (ACC · H(2)O) → dehydrated amorphous calcium carbonate (ACC) → calcite. Unexpectedly, we find ACC · H(2)O-rich nanoparticles that persist after the surrounding mineral has dehydrated and crystallized. Protein matrix components occluded within the mineral must inhibit ACC · H(2)O dehydration. We devised an in vitro, also using XANES-PEEM, assay to identify spicule proteins that may play a role in stabilizing various mineral phases, and found that the most abundant occluded matrix protein in the sea urchin spicules, SM50, stabilizes ACC · H(2)O in vitro.


Assuntos
Materiais Biocompatíveis/química , Calcificação Fisiológica , Carbonato de Cálcio/química , Transição de Fase , Animais , Materiais Biocompatíveis/metabolismo , Carbonato de Cálcio/metabolismo , Cristalização , Embrião não Mamífero/química , Embrião não Mamífero/metabolismo , Embrião não Mamífero/ultraestrutura , Proteínas da Matriz Extracelular/genética , Proteínas da Matriz Extracelular/metabolismo , Regulação da Expressão Gênica no Desenvolvimento , Microscopia Eletrônica/métodos , Minerais/química , Minerais/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Strongylocentrotus purpuratus/química , Strongylocentrotus purpuratus/embriologia , Strongylocentrotus purpuratus/metabolismo , Água/química , Espectroscopia por Absorção de Raios X/métodos
19.
Forensic Sci Int ; 210(1-3): 47-51, 2011 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-21354727

RESUMO

Multilayered glitter particles were cut with a microtome into thin cross-sections and examined using an FT-IR microscope with a synchrotron infrared source. The high brightness of the synchrotron source enabled high-quality infrared spectra to be quickly obtained from individual layers in the glitter particle cross-section, providing additional chemical information that could increase the glitter particle's value as associative evidence in criminal cases.

20.
Nano Lett ; 11(2): 466-70, 2011 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-21166443

RESUMO

We studied the insulator-metal transition (IMT) in single-domain, single crystalline vanadium dioxide (VO(2)) microbeams with infrared microspectroscopy. The unique nature of such samples allowed us to probe the intrinsic behavior of both insulating and metallic phases in the close vicinity of IMT, and investigate the IMT driven by either strain or temperature independently. We found that the VO(2) insulating band gap narrows rapidly upon heating, and the infrared response undergoes an abrupt transition at both strain- and temperature-induced IMT. The results are consistent with recent studies attributing the opening of VO(2) insulating band gap to a correlation-assisted Peierls transition.


Assuntos
Nanoestruturas/química , Óxidos/química , Semicondutores , Vanádio/química , Condutividade Elétrica , Transporte de Elétrons , Luz , Substâncias Macromoleculares/química , Teste de Materiais , Conformação Molecular , Nanoestruturas/ultraestrutura , Tamanho da Partícula , Espalhamento de Radiação , Propriedades de Superfície
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