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1.
Chemistry ; 28(32): e202201391, 2022 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-35575466

RESUMO

Invited for the cover of this issue are Chih-Min Wang and co-workers at Academia Sinica of Taiwan and National Taiwan Ocean University. The image depicts an unusual organic-inorganic hybrid zinc phosphite with interesting structural features and gas adsorption properties. Read the full text of the article at 10.1002/chem.202200732.


Assuntos
Dióxido de Carbono , Adsorção , Humanos , Fosfitos
2.
Chemistry ; 28(32): e202200732, 2022 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-35429358

RESUMO

An uncommon example of stable mixed-ligand zinc phosphite with genuine pores has been synthesized by using zinc metal, inorganic phosphite acid, thio-functionalized O-donor (2,5-thiophenedicarboxylate, TPDC), and tetradentate N-donor [1,2,4,5-tetrakis(imidazol-1-ylmethyl)benzene, TIMB] units assembled into one crystalline structure according to a hydro(solvo)thermal method. This is a very rare case of a metal phosphite incorporating both N- and O-donor ligands. The tetradentate TIMB linker bound to zinc atoms of the isolated zincophosphite hexamers to form a 3D open-framework structure by crosslinking structural components of 1D chains and 2D layers. Here, the TPDC ligand acts as a monodentate binding model to functionalize its porous structure with the uncoordinated S atom and COO- group. Interestingly, this compound demonstrates the highest H2 storage capacity among organic-inorganic hybrid metal phosphates (and phosphites), and a good CO2 capture at 298 K compared with the majority of crystalline materials. The possible adsorption sites and selectivity for CO2 over H2 , N2 , and CO at 298 K were calculated by using density functional theory (DFT), the ideal adsorption solution theory (IAST), and fitting experimental pure-component adsorption data.

3.
Dalton Trans ; 49(32): 11085-11089, 2020 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-32662470

RESUMO

The first example of a thio-functionalized zincophosphite material (NTOU-2S) incorporating the 2,5-thiophenedicarboxylate (TPDC) ligands was synthesized using a hydro(solvo)thermal method and structurally characterized by single-crystal X-ray diffraction. Interestingly, the perspective view of the crystal structure for NTOU-2S is similar to our previous report of NTOU-2 but the carboxylate organic ligands (TPDC for NTOU-2S; 1,4-benzenedicarboxylate, BDC, for NTOU-2) in both compounds adopt different types of bis-monodentate coordination models (the unusual cis bonding versus a trans linkage) to bridge the metal atoms of inorganic tubes in the formation of large-channel zincophosphite frameworks, resulting in structural and functional diversities. The thiophene-based compound also displayed higher thermal stability and removal ability for the softer Hg2+ cations from water solutions than the performance of sulfur-free NTOU-2. In addition, the synthesis, structural characteristics, removal properties of heavy metal cations, and thermal and chemical stabilities for both compounds were also reported.

4.
Medicine (Baltimore) ; 94(52): e2375, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26717382

RESUMO

The en-bloc resection of neoplasms on the abdominal wall often causes extensive defects that are difficult to manage. The anterolateral thigh (ALT) flap is a widely used flap in reconstructive surgery of defects. In this article, we present a case using bilateral pedicle anterolateral thigh flaps combined with a surgical polymesh to repair a large defect (22 cm × 18 cm) caused by dissection of a recurrent fibromatosis with good functional and aesthetic effects. There were no obvious morbidities or complications during a 6-month follow-up period.We conclude that the bilateral pedicle anterolateral thigh flap is a good choice for reconstruction of large lower abdominal wall defects. It can afford sufficient soft tissue coverage without obvious donor site morbidity.


Assuntos
Abdome/cirurgia , Procedimentos de Cirurgia Plástica/métodos , Retalhos Cirúrgicos/cirurgia , Telas Cirúrgicas , Coxa da Perna/cirurgia , Neoplasias Abdominais/cirurgia , Adulto , Fibroma/cirurgia , Humanos , Masculino , Procedimentos de Cirurgia Plástica/instrumentação
5.
Nat Nanotechnol ; 9(10): 845-50, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25240673

RESUMO

Besides adding a new functionality to conventional lasers, spin-polarized lasers can, potentially, offer lower threshold currents and reach higher emission intensities. However, to achieve spin-polarized lasing emission a material should possess a slow spin relaxation and a high propensity to be injected with spin-polarized currents. These are stringent requirements that, so far, have limited the choice of candidate materials for spin-lasers. Here we show that these requirements can be relaxed by using a new self-polarized spin mechanism. Fe3O4 nanoparticles are coupled to GaN nanorods to form an energy-band structure that induces the selective charge transfer of electrons with opposite spins. In turn, this selection mechanism generates the population imbalance between spin-up and spin-down electrons in the emitter's energy levels without an external bias. Using this principle, we demonstrate laser emission from GaN nanorods with spin polarization up to 28.2% at room temperature under a low magnetic field of 0.35 T. As the spin-selection mechanism relies entirely on the relative energy-band alignment between the iron oxide nanoparticles and the emitter and requires neither optical pumping with circularly polarized light nor electrical pumping with magnetic electrodes, potentially a wide range of semiconductors can be used as spin-nanolasers.

6.
Opt Express ; 21(17): 19934-42, 2013 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-24105539

RESUMO

An optically tunable and detectable magnetoeletric (ME) effect has been discovered in the composite consisting of InGaN/GaN multiple quantum wells and magnetostrictive ferromagnetic Ni or FeCo thin films at room temperature. Due to the interactively optical and piezoelectric properties of nitride semiconductors, this composite provides an intriguing optically accessible system, in which the magnetoelectric effect can be both easily tuned and detected. The underlying mechanism can be well accounted for by the interplay among magnetostrictive, piezoelectric and optical transition. It thus offers a new paradigm to generate artificial material systems with magnetic/electric/optical inter-related/controllable properties.

7.
Sci Rep ; 3: 2694, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24045846

RESUMO

Photodetectors with ultrahigh sensitivity based on the composite made with all carbon-based materials consisting of graphite quantum dots (QDs), and two dimensional graphene crystal have been demonstrated. Under light illumination, remarkably, a photocurrent responsivity up to 4 × 10(7) AW(-1) can be obtained. The underlying mechanism is attributed to the spatial separation of photogenerated electrons and holes due to the charge transfer caused by the appropriate band alignment across the interface between graphite QDs and graphene. Besides, the large absorptivity of graphite QDs and the excellent conductivity of the graphene sheet also play significant roles. Our result therefore demonstrates an outstanding illustration for the integration of the distinct properties of nanostructured carbon materials with different dimensionalities to achieve highly efficient devices. Together with the associated mechanism, it paves a valuable step for the further development of all carbon-based, cheap, and non-toxic optoelectronics devices with excellent performance.

8.
Nanotechnology ; 23(35): 355201, 2012 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-22895012

RESUMO

A new type of pyroelectric field effect transistor based on a composite consisting of single zinc oxide nanowire and lead zirconate titanate (ZnO NW-PZT) has been developed. Under infrared (IR) laser illumination, the transconductance of the ZnO NW can be modulated by optothermal gating. The drain current can be increased or decreased by IR illumination depending on the polarization orientation of the Pb(Zr(0.3)Ti(0.7))O(3) (PZT) substrate. Furthermore, by combining the photocurrent behavior in the UV range and the optothermal gating effect in the IR range, the wide spectrum of response of current by light offers a variety of opportunities for nanoscale optoelectronic devices.

9.
Opt Lett ; 36(13): 2563-5, 2011 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-21725480

RESUMO

FeCo/NiO half-shell arrays were fabricated based on the periodic monolayer polystyrene spheres. The two-dimensional magnetic periodic arrays form well-defined photonic crystals with pronounced stop bands. Quite interestingly, it is found that the stop bands can be tuned by an external magnetic field. The underlying mechanism is attributed to the controllable dielectric constant of the magnetic FeCo film under an applied magnetic field. The results shown here may open up an avenue for magnetically tunable photonic crystal stop bands, which may be useful for the creation of new magneto-optical devices.

10.
Nanotechnology ; 22(33): 335701, 2011 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-21775805

RESUMO

The electron transport behavior in chemically reduced graphene oxide (rGO) sheets with different thicknesses of 2, 3, and 5 nm was investigated. The four-probe method for the sheet resistance (R(S)) measurement on the intensively reduced graphene oxide samples indicates an Arrhenius characteristic of the electron transport at zero magnetic field B = 0, consistent with previous experimental results on well-reduced GO samples. The anticipated variable range hopping (VRH) transport of electrons in a two-dimensional electron system at low temperatures was not observed. The measured R(S) of the rGO samples are below 52 kΩ/square at room temperature. With the application of a magnetic field up to 4 T, negative magnetoresistance in the Mott VRH regime was observed. The magnetotransport features support a model based on the spin-coupling effect from the vacancy-induced midgap states that facilitate the Mott VRH conduction in the presence of an external magnetic field.

11.
Opt Lett ; 36(4): 514-6, 2011 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-21326440

RESUMO

We demonstrate magnetically tunable surface plasmon resonance based on a composite consisting of noble metal nanoparticles and ferromagnetic thin film. We found that both the frequency and linewidth of the localized surface plasmon resonance can be manipulated by applying an external magnetic field. The underlying mechanism is attributed to the variation of the dielectric constant in the ferromagnetic thin film resulting from the change of magnetization. Our result shown here paves an alternative route for manipulation of the characteristics of the surface plasmon resonance, which may serve as a new design concept for the development of magneto-optical devices.

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