MyMedR

Superior photoelectrocatalytic performance of ternary structural BiVO4/GQD/g-C3N4 heterojunction

Samsudin MFR, Ullah H, Tahir AA, Li X, Ng YH, Sufian S

J Colloid Interface Sci, 2021 Mar 15;586:785-796.

PMID: 33198982 DOI: 10.1016/j.jcis.2020.11.003

Herein, we performed an encyclopedic analysis on the photoelectrocatalytic hydrogen production of BiVO4/g-C3N4 decorated with reduced graphene oxide (RGO) or graphene quantum dots (GQDs). The differences between RGO and GQDs as an electron mediator was revealed for the first time in the perspective of theoretical DFT analysis and experimental validation. It was found that the incorporation of GQDs as an electron mediator promotes better photoelectrocatalytic hydrogen performance in comparison to the RGO. The addition of GQD can significantly improve the activity by 25.2 and 75.7% in comparison to the BiVO4/RGO/g-C3N4 and binary composite samples, respectively. Correspondingly, the BiVO4/GQD/g-C3N4 attained the highest photocurrent density of 19.2 mA/cm2 with an ABPE of 0.57% without the presence of any sacrificial reagents. This enhancement is stemming from the low photocharge carrier transfer resistance which was further verified via DFT study. The DFT analysis revealed that the BiVO4/GQD/g-C3N4 sample shared their electronic cloud density through orbital hybridization while the BiVO4/RGO/g-C3N4 sample show less mutual sharing. Additionally, the charge redistribution of the GQDs-composite at the heterostructure interface articulates a more stable and stronger heterojunction than the RGO-composite. Notably, this study provides new insights on the effect of different carbonaceous materials (RGO and GQDs) which are often used as an electron mediator to enhance photocatalytic activity.

Matched MeSH terms: Electrons

Sulfur-doped graphitic carbon nitride incorporated bismuth oxychloride/Cobalt based type-II heterojunction as a highly stable material for photoelectrochemical water splitting

Vinoth S, Ong WJ, Pandikumar A

J Colloid Interface Sci, 2021 Jun;591:85-95.

PMID: 33592528 DOI: 10.1016/j.jcis.2021.01.104

Cobalt incorporated sulfur-doped graphitic carbon nitride with bismuth oxychloride (Co/S-gC3N4/BiOCl) heterojunction is prepared by an ultrasonically assisted hydrothermal treatment. The heterojunction materials have employed in photoelectrochemical (PEC) water splitting. The PEC activity and stability of the materials are promoted by constructing an interface between the visible light active semiconductor photocatalyst and cocatalysts. The photocurrent density of Co-9% S-gC3N4/BiOCl has attained 393.0 μA cm-2 at 1.23 V vs. RHE, which is 7-fold larger than BiOCl and ~3-fold higher than 9% S-gC3N4/BiOCl. The enhanced PEC activity can be attributed to the improved electron-hole charge separation and the boosted charge transfer is confirmed by photoluminescence (PL) and electrochemical impedance spectroscopy (EIS) analysis. The fabricated Co/S-gC3N4/BiOCl nanohybrid material has exhibited high stability of up to 10,800 s (3 h) at 1.23 V vs. RHE during PEC water splitting reaction and the obtained photo-conversion efficiency is 3.7-fold greater than S-gC3N4/BiOCl and 17-fold higher than BiOCl. The FESEM and HRTEM images have revealed the formation of heterojunction interface between S-gC3N4 and BiOCl and the elemental mapping has confirmed the presence of cobalt over S-gC3N4/BiOCl. The heterojunction interface has facilitated the photo-excited charge separation and transport across the electrode/electrolyte interface and also the flat-band potential, which is confirmed by Mott-Schottky analysis.

Matched MeSH terms: Electrons

Studies on the interaction of mononuclear metal(II) complexes of amino‑naphthoquinone with bio-macromolecules

Kosiha A, Lo KM, Parthiban C, Elango KP

Mater Sci Eng C Mater Biol Appl, 2019 Jan 01;94:778-787.

PMID: 30423764 DOI: 10.1016/j.msec.2018.10.021

Three metal(II) complexes [CoLCl2], [CuLCl2] and [ZnL2Cl2] {L = 2‑chloro‑3‑((3‑dimethylamino)propylamino)naphthalene‑1,4‑dione} have been synthesized and characterized using analytical, thermal and spectral techniques (FT-IR, UV-Vis, ESR and ESI-MS). The structure of the L has been confirmed by single crystal XRD study. The complexes show good binding propensity to bovine serum albumin (BSA) having relatively higher binding constant values (104 M-1) than the ligand. Fluorescence spectral studies indicate that [CoLCl2] binds relatively stronger with CT DNA through intercalative mode, exhibiting higher binding constant (2.22 × 105 M-1). Agarose gel electrophoresis run on plasmid DNA (pUC18) prove that all the complexes showed efficient DNA cleavage via hydroxyl radical mechanism. The complexes were identified as potent anticancer agents against two human cancer cell lines (MCF7 and A549) by comparing with cisplatin. Co(II) complex demonstrated greater cytotoxicity against MCF7 and A549 cells with IC50 values at 19 and 22 μM, respectively.

Matched MeSH terms: Electrons

Structural and optical properties investigation on h-bonded 1d helical selfassembly of 1,1-dibenzyl-3-(2-bromobenzoyl)thiourea molecules for nonlinear optical application

Wun Fui Mark-Lee, Mohammad B. Kassim, Mohd Faizal Md Nasir

Sains Malaysiana, 2018;47:741-747.

A benzoylthiourea molecule namely 1,1-dibenzyl-3-(2-bromobenzoyl)thiourea (2BrBT) was synthesized and characterized
by C, H, N and S elemental, mass spectrometry and spectroscopic analyses (infrared, ultraviolet-visible and nuclear
magnetic resonance). The 2BrBT compound crystallized in a tetragonal system with the space group P43 and exhibits
an acentric crystalline packing due to the presence of intermolecular H-bonding network that forms a self-assembly
of 1D helical motif. The asymmetric delocalisation of electrons in the molecule retains its transparency throughout the
visible and near-infrared region and hence, essentially propagates the macroscopic helical motif in the solid state. The
highest-occupied and lowest-unoccupied molecular orbital (HOMO/LUMO) are mainly found on the thiourea moiety and
the benzoylthiourea fragment, respectively and shows an optical bandgap of 3.50 eV. The influence of its geometrical
characteristics to the optical properties of 2BrBT is established and discussed in view of nonlinear optical (NLO)
application.

Matched MeSH terms: Electrons

Sorption of ionized dyes on high-salinity microalgal residue derived biochar: Electron acceptor-donor and metal-organic bridging mechanisms

Tan X, Zhu S, Show PL, Qi H, Ho SH

J Hazard Mater, 2020 07 05;393:122435.

PMID: 32151933 DOI: 10.1016/j.jhazmat.2020.122435

Biochar (BC) has attracted much attention owing to its superior sorption capacity towards ionized organic contaminants. However, the mechanism of ionized organics sorption occurring within BC containing large amounts of minerals is still controversial. In this study, we demonstrate the physicochemical structure of high-salinity microalgal residue derived biochar (HSBC) and elucidate the corresponding sorption mechanisms for four ionized dyes along with determining the crucial role of involved minerals. The results indicate that sodium and calcium minerals mainly exist within HSBCs, and the pyrolysis temperature can dramatically regulate the phases and interfacial property of both carbon matrix and minerals. As a result, the HSBC shows a higher sorption potential, benefiting from abundant functional groups and high content of inorganic minerals. Using theoretical calculations, the activities of electron donor-acceptor interaction between HSBCs and different dyes are clearly illustrated, thereby identifying the critical role of Ca2+ in enhancing the removal of ionized dyes in HSBCs. In addition, Ca-containing minerals facilitate the sorption of ionized dyes in HSBCs by forming ternary complexes through metal-bridging mechanism. These results of mineral-induced dye sorption mechanisms help to better understand the sorption of ionized organics in high-salt containing BC and provide a new disposal strategy for hazardous microalgal residue, as well as provide a breakthrough in making the remediation of ionized organic contaminated microalgal residue derived absorbent feasible.

Matched MeSH terms: Electrons

Smart electrical bi-layers lipopeptides: Novel peptidic chains like zigzag map esterified with phospho-glyceride as mono-layer moieties capable in forming a meso-sphere- envelop with scaffold- ability to cellular impurities

Saadi S, Saari N, Abdulkarim MS, Ghazali HM, Anwar F

J Control Release, 2018 03 28;274:93-101.

PMID: 29031897 DOI: 10.1016/j.jconrel.2017.10.011

Cell impurities are an emerging nucleating molecular barriers having the capability in disordering the metabolic chain reactions of proteolysis, glycolysis and lipolysis. Their massive effects induced by copolymer crystal growth in compaction with metal and mineral transients are extended as well as in damaging DNA and mRNA structure motif and other molecular assembly e.g. histones structure unites. Their polycrystalline packing modes, polydispersity and their tendency to surface and interface adhesion prompted us in structuring scaffold biomaterials enriched with biopeptides, layered by phospho-glycerides ester-forms. The interface tension of the formed map is flexible and dependent to the surface exposure and its collapse modes to the surrounding molecular ligands. Thus, the attempts in increasing surface exposure e.g. the viscoelastic of structured lipopeptides and types of formed network structures interplays an extra- conjugating biomolecules having a least cytotoxicity effects to cells constituents. Disulfides molecules are selected to be the key regulatory element in rejoining both lipidic and proteic moieties by disordering atoms status via chemical ionization using organic catalyst. The insertion of methionine based peptidic chain at the lateral surfaces of scaffold biomaterials enhances the electron-meta-static motions by raising a molecular disordering status at distinct regions of the map e.g. epimerization into a nonpolar side that helps the chemical conjunction of disulfide groups with the esterified phosphoglycerides mono-layers. These effects in turn are accomplished by the formation of meso-sphere nonpolar- vesicles. The oxidation of disulfide group would alter the ordering of initial molecules by raising a newly molecular disorders to the map with high polarity to surface regions. In the same time indicates a continuation in the crystallization growth factor via a low chemical lesions between the impurities and a supersaturation in the intra-atomic distances with maximum cross linking to the deformed ligand with scaffold biomaterials.

Matched MeSH terms: Electrons

Size-Controlled and Optical Properties of Platinum Nanoparticles by Gamma Radiolytic Synthesis

Gharibshahi E, Saion E, Ashraf A, Gharibshahi L

Appl Radiat Isot, 2017 Dec;130:211-217.

PMID: 29028581 DOI: 10.1016/j.apradiso.2017.09.012

Gamma radiolytic synthesis was used to produce size-controlled spherical platinum nanoparticles from an aqueous solution containing platinum tetraammine and polyvinyl pyrrolidone. The structural characterizations were performed using X-ray diffraction, and transmission electron microscopy. The transmission electron microscopy was used to determine the average particle diameter, which decreased from 4.4nm at 80kGy to 2.8nm at 120kGy. The UV-visible absorption spectrum was measured and found that platinum nanoparticles exhibit two steady absorption maxima in UV regions due to plasmonic excitation of conduction electrons, which blue shifted to lower wavelengths with a decrease in particle size. We consider the conduction electrons of platinum nanoparticles to follow Thomas-Fermi-Dirac-Weizsacker atomic model that they are not entirely free but weakly bounded to particles at lower-energy states {n = 5, l = 2 or 5d} and {n = 6, l = 0 or 6s}, which upon receiving UV photon energy the electrons make intra-band quantum excitations to higher-energy states allowed by the principles of quantum number that results the absorption maxima. We found an excellent agreement between the experimental and theoretical results, which suggest that the optical absorption of metal nanoparticles could be fundamentally described by a quantum mechanical interpretation, which could be more relevant to photo-catalysis and heterogeneous catalysis.

Matched MeSH terms: Electrons

Simulation on the roles of the number of quantum well and doping in Inx Ga1-xN multiple quantum wells LEDs

Zainal N, Azimah E, Hassan Z, Abu Hassan H, Hashim M

Sains Malaysiana, 2014;43:1557-1564.

In this work, the emission efficiency of InxGa1-xN based light emitting diodes (LEDs) had been numerically investigated with the variation of the number of quantum well. From our calculation, we found that non-uniformity of carriers distribution (especially electron) in the wells leads to serious inhomogeneity of radiative recombination distribution that would degrade the efficiency of the LED with more wells. However, the problem was minimized when the selected quantum barriers were doped with a reasonable doping level. Comparison with other reported experimental works were also included. At the end of this work, we proposed several types of preferable LEDs designs with optimum structural parameters.

Matched MeSH terms: Electrons

Fulltext Significantly improved photovoltaic performance in polymer bulk heterojunction solar cells with graphene oxide /PEDOT:PSS double decked hole transport layer

Rafique S, Abdullah SM, Shahid MM, Ansari MO, Sulaiman K

Sci Rep, 2017 01 13;7:39555.

PMID: 28084304 DOI: 10.1038/srep39555

This work demonstrates the high performance graphene oxide (GO)/PEDOT:PSS doubled decked hole transport layer (HTL) in the PCDTBT:PC71BM based bulk heterojunction organic photovoltaic device. The devices were tested on merits of their power conversion efficiency (PCE), reproducibility, stability and further compared with the devices with individual GO or PEDOT:PSS HTLs. Solar cells employing GO/PEDOT:PSS HTL yielded a PCE of 4.28% as compared to either of individual GO or PEDOT:PSS HTLs where they demonstrated PCEs of 2.77 and 3.57%, respectively. In case of single GO HTL, an inhomogeneous coating of ITO caused the poor performance whereas PEDOT:PSS is known to be hygroscopic and acidic which upon direct contact with ITO reduced the device performance. The improvement in the photovoltaic performance is mainly ascribed to the increased charge carriers mobility, short circuit current, open circuit voltage, fill factor, and decreased series resistance. The well matched work function of GO and PEDOT:PSS is likely to facilitate the charge transportation and an overall reduction in the series resistance. Moreover, GO could effectively block the electrons due to its large band-gap of ~3.6 eV, leading to an increased shunt resistance. In addition, we also observed the improvement in the reproducibility and stability.

Matched MeSH terms: Electrons

Signet-ring Cell Lymphoma-a Case Report

Masir N, Cheong SK, Noordin K

Hematology, 2001;6(3):187-92.

PMID: 27420125 DOI: 10.1080/10245332.2001.11746571

A case of signet-ring cell lymphoma diagnosed initially by fine needle aspiration cytology is reported. This rare tumor is a variant of follicular lymphoma, which closely resembles metastatic adenocarcinoma and other tumors which exhibit signet-ring cell appearance. Correct diagnosis can be achieved by careful morphologic analysis together with positive reactivity with lymphoid markers. The cytohistologic, immunohistochemical and electron microscopic features are described, and the differ ential diagnostic considerations are discussed in the report.

Matched MeSH terms: Electrons

Fulltext Sensitive Fibre-Based Thermoluminescence Detectors for High Resolution In-Vivo Dosimetry

Ghomeishi M, Mahdiraji GA, Adikan FR, Ung NM, Bradley DA

Sci Rep, 2015;5:13309.

PMID: 26314683 DOI: 10.1038/srep13309

With interest in the potential of optical fibres as the basis of next-generation thermoluminescence dosimeters (TLDs), the development of suitable forms of material and their fabrication has become a fast-growing endeavour. Present study focuses on three types of Ge-doped optical fibres with different structural arrangements and/or shapes, namely conventional cylindrical fibre, capillary fibre, and flat fibre, all fabricated using the same optical fibre preform. For doses from 0.5 to 8 Gy, obtained at electron and photon energies, standard thermoluminescence (TL) characteristics of the optical fibres have been the subject of detailed investigation. The results show that in collapsing the capillary fibre into a flat shape, the TL yield is increased by a factor of 5.5, the yield being also some 3.2 times greater than that of the conventional cylindrical fibre fabricated from the same perform. This suggests a means of production of suitably sensitive TLD for in-vivo dosimeter applications. Addressing the associated defects generating luminescence from each of the optical fibres, the study encompasses analysis of the TL glow curves, with computerized glow curve deconvolution (CGCD) and 2(nd) order kinetics.

Matched MeSH terms: Electrons

Self-assembled heteropolyacid on nitrogen-enriched carbon nanofiber for vanadium flow batteries

Etesami M, Abouzari-Lotf E, Sha'rani SS, Miyake M, Moozarm Nia P, Ripin A, et al.

Nanoscale, 2018 Jul 13;10(27):13212-13222.

PMID: 29971298 DOI: 10.1039/c8nr02450b

A novel polyoxometalate-based electrode was developed by incorporating phosphotungstic acid (PWA) in nylon-6,6 nanofiber, followed by carbonization. The developed PWA-carbon nanofiber (PWA-CNF) showed the characteristics of the dual-scale porosity of micro- and mesoporous substrate with surface area of around 684 m2 g-1. The compound exhibited excellent stability in vanadium electrolyte and battery cycling. Evaluation of electrocatalytic properties toward V2+/V3+ and VO2+/VO2+ redox couples indicated promising advantages in electron transfer kinetics and increasing energy efficiency, particularly for the VO2+/VO2+ couple. Moreover, the developed electrode exhibited substantially improved energy efficiency (14% higher than that of pristine carbon felt) in the single cell vanadium redox flow battery. This outstanding performance was attributed to high surface area and abundant oxygen-containing linkages in the developed electrode.

Matched MeSH terms: Electrons

Search for single production of vector-like quarks decaying to a top quark and a W boson in proton-proton collisions at s = 13 TeV

Sirunyan AM, Tumasyan A, Adam W, Ambrogi F, Asilar E, Bergauer T, et al.

Eur Phys J C Part Fields, 2019;79(2):90.

PMID: 30814908 DOI: 10.1140/epjc/s10052-019-6556-3

A search is presented for the single production of vector-like quarks in proton-proton collisions at

s

=
13

TeV

. The data, corresponding to an integrated luminosity of 35.9

fb

-
1

, were recorded with the CMS experiment at the LHC. The analysis focuses on the vector-like quark decay into a top quark and a
W
boson, with one muon or electron in the final state. The mass of the vector-like quark candidate is reconstructed from hadronic jets, the lepton, and the missing transverse momentum. Methods for the identification of
b
quarks and of highly Lorentz boosted hadronically decaying top quarks and
W
bosons are exploited in this search. No significant deviation from the standard model background expectation is observed. Exclusion limits at 95% confidence level are set on the product of the production cross section and branching fraction as a function of the vector-like quark mass, which range from 0.3 to 0.03

pb

for vector-like quark masses of 700 to 2000

GeV

. Mass exclusion limits up to 1660

GeV

are obtained, depending on the vector-like quark type, coupling, and decay width. These represent the most stringent exclusion limits for the single production of vector-like quarks in this channel.

Matched MeSH terms: Electrons

Search for displaced supersymmetry in events with an electron and a muon with large impact parameters

Khachatryan V, Sirunyan AM, Tumasyan A, Adam W, Bergauer T, Dragicevic M, et al.

Phys Rev Lett, 2015 Feb 13;114(6):061801.

PMID: 25723204

A search for new long-lived particles decaying to leptons is presented using proton-proton collisions produced by the LHC at √[s]=8 TeV. Data used for the analysis were collected by the CMS detector and correspond to an integrated luminosity of 19.7 fb(-1). Events are selected with an electron and muon with opposite charges that both have transverse impact parameter values between 0.02 and 2 cm. The search has been designed to be sensitive to a wide range of models with nonprompt e-μ final states. Limits are set on the "displaced supersymmetry" model, with pair production of top squarks decaying into an e-μ final state via R-parity-violating interactions. The results are the most restrictive to date on this model, with the most stringent limit being obtained for a top squark lifetime corresponding to cτ=2 cm, excluding masses below 790 GeV at 95% confidence level.

Matched MeSH terms: Electrons

Search for Heavy Neutral Leptons in Events with Three Charged Leptons in Proton-Proton Collisions at sqrt[s]=13 TeV

Sirunyan AM, Tumasyan A, Adam W, Ambrogi F, Asilar E, Bergauer T, et al.

Phys Rev Lett, 2018 Jun 01;120(22):221801.

PMID: 29906166 DOI: 10.1103/PhysRevLett.120.221801

A search for a heavy neutral lepton N of Majorana nature decaying into a W boson and a charged lepton is performed using the CMS detector at the LHC. The targeted signature consists of three prompt charged leptons in any flavor combination of electrons and muons. The data were collected in proton-proton collisions at a center-of-mass energy of 13 TeV, with an integrated luminosity of 35.9 fb^{-1}. The search is performed in the N mass range between 1 GeV and 1.2 TeV. The data are found to be consistent with the expected standard model background. Upper limits are set on the values of |V_{eN}|^{2} and |V_{μN}|^{2}, where V_{ℓN} is the matrix element describing the mixing of N with the standard model neutrino of flavor ℓ. These are the first direct limits for N masses above 500 GeV and the first limits obtained at a hadron collider for N masses below 40 GeV.

Matched MeSH terms: Electrons

Search for Evidence of the Type-III Seesaw Mechanism in Multilepton Final States in Proton-Proton Collisions at sqrt[s]=13 TeV

Sirunyan AM, Tumasyan A, Adam W, Ambrogi F, Asilar E, Bergauer T, et al.

Phys Rev Lett, 2017 Dec 01;119(22):221802.

PMID: 29286783 DOI: 10.1103/PhysRevLett.119.221802

A search for a signal consistent with the type-III seesaw mechanism in events with three or more electrons or muons is presented. The data sample consists of proton-proton collisions at sqrt[s]=13 TeV collected by the CMS experiment at the LHC in 2016 and corresponds to an integrated luminosity of 35.9 fb^{-1}. Selection criteria based on the number of leptons and the invariant mass of oppositely charged lepton pairs are used to distinguish the signal from the standard model background. The observations are consistent with the expectations from standard model processes. The results are used to place limits on the production of heavy fermions of the type-III seesaw model as a function of the branching ratio to each lepton flavor. In the scenario of equal branching fractions to each lepton flavor, heavy fermions with masses below 840 GeV are excluded. This is the most sensitive probe to date of the type-III seesaw mechanism.

Matched MeSH terms: Electrons

Search for Charged Higgs Bosons Produced via Vector Boson Fusion and Decaying into a Pair of W and Z Bosons Using pp Collisions at sqrt[s]=13 TeV

Sirunyan AM, Tumasyan A, Adam W, Asilar E, Bergauer T, Brandstetter J, et al.

Phys Rev Lett, 2017 Oct 06;119(14):141802.

PMID: 29053305 DOI: 10.1103/PhysRevLett.119.141802

A search for charged Higgs bosons produced via vector boson fusion and decaying into W and Z bosons using proton-proton collisions at sqrt[s]=13 TeV is presented. The data sample corresponds to an integrated luminosity of 15.2 fb^{-1} collected with the CMS detector in 2015 and 2016. The event selection requires three leptons (electrons or muons), two jets with large pseudorapidity separation and high dijet mass, and missing transverse momentum. The observation agrees with the standard model prediction. Limits on the vector boson fusion production cross section times branching fraction for new charged physical states are reported as a function of mass from 200 to 2000 GeV and interpreted in the context of Higgs triplet models.

Matched MeSH terms: Electrons

Fulltext Sciatic nerve repair with tissue engineered nerve: Olfactory ensheathing cells seeded poly(lactic-co-glygolic acid) conduit in an animal model

Tan CW, Ng MH, Ohnmar H, Lokanathan Y, Nur-Hidayah H, Roohi SA, et al.

Indian J Orthop, 2013 Nov;47(6):547-52.

PMID: 24379458 DOI: 10.4103/0019-5413.121572

BACKGROUND AND AIM: Synthetic nerve conduits have been sought for repair of nerve defects as the autologous nerve grafts causes donor site morbidity and possess other drawbacks. Many strategies have been investigated to improve nerve regeneration through synthetic nerve guided conduits. Olfactory ensheathing cells (OECs) that share both Schwann cell and astrocytic characteristics have been shown to promote axonal regeneration after transplantation. The present study was driven by the hypothesis that tissue-engineered poly(lactic-co-glycolic acid) (PLGA) seeded with OECs would improve peripheral nerve regeneration in a long sciatic nerve defect.

MATERIALS AND METHODS: Sciatic nerve gap of 15 mm was created in six adult female Sprague-Dawley rats and implanted with PLGA seeded with OECs. The nerve regeneration was assessed electrophysiologically at 2, 4 and 6 weeks following implantation. Histopathological examination, scanning electron microscopic (SEM) examination and immunohistochemical analysis were performed at the end of the study.

RESULTS: Nerve conduction studies revealed a significant improvement of nerve conduction velocities whereby the mean nerve conduction velocity increases from 4.2 ΁ 0.4 m/s at week 2 to 27.3 ΁ 5.7 m/s at week 6 post-implantation (P < 0.0001). Histological analysis revealed presence of spindle-shaped cells. Immunohistochemical analysis further demonstrated the expression of S100 protein in both cell nucleus and the cytoplasm in these cells, hence confirming their Schwann-cell-like property. Under SEM, these cells were found to be actively secreting extracellular matrix.

CONCLUSION: Tissue-engineered PLGA conduit seeded with OECs provided a permissive environment to facilitate nerve regeneration in a small animal model.

Matched MeSH terms: Electrons

Fulltext Scalable Mesoporous Platinum Diselenide Nanosheet Synthesis in Water

Ali Umar A, Md Saad SK, Mat Salleh M

ACS Omega, 2017 Jul 31;2(7):3325-3332.

PMID: 31457657 DOI: 10.1021/acsomega.7b00580

Newly discovered two-dimensional (2D) atomic crystals (nanosheet) of platinum diselenide (PtSe2) have progressively attracted attention due to their expected high performance in catalysis, sensing, electronics, and optoelectronics applications. Further extraordinary physicochemical properties are expected if these nanosheets of platinum diselenide can possess mesoporosity as this may enable a high range of molecular adsorption, enhancing their functionalities in catalysis, batteries, supercapacitors, and sensing. Here, we present for the first time a straightforward, aqueous-phase synthetic strategy for the preparation of scalable nanosheets of platinum diselenide with mesoporous structure via a surfactant-templated self-assembly followed by a thermal annealing phase-transformation process. We used hexamethylenetetramine as a hexagonal honeycomb (sp2-sp3 orbital) scaffold for assembling the Pt and Se organic complexes to form the nanosheet structure, which is stable, preserving the 2D structure and mesoporosity during a thermal annealing at 500 °C. Density functional theory analysis then indicated that the mesoporous nanosheets of platinum diselenide exhibit a high free-energy and large density of π electrons crossing the Fermi level, inferring a high-catalytic performance. This effortless strategy is currently being extended to the synthesis of other transition metal dichalcogenides, including the preparation of multi-metal atomic dichalcogenide nanosheets, for a wide variety of scientific and technological applications.

Matched MeSH terms: Electrons

Fulltext Reversible structure manipulation by tuning carrier concentration in metastable Cu2S

Tao J, Chen J, Li J, Mathurin L, Zheng JC, Li Y, et al.

Proc Natl Acad Sci U S A, 2017 09 12;114(37):9832-9837.

PMID: 28855335 DOI: 10.1073/pnas.1709163114

The optimal functionalities of materials often appear at phase transitions involving simultaneous changes in the electronic structure and the symmetry of the underlying lattice. It is experimentally challenging to disentangle which of the two effects--electronic or structural--is the driving force for the phase transition and to use the mechanism to control material properties. Here we report the concurrent pumping and probing of Cu2S nanoplates using an electron beam to directly manipulate the transition between two phases with distinctly different crystal symmetries and charge-carrier concentrations, and show that the transition is the result of charge generation for one phase and charge depletion for the other. We demonstrate that this manipulation is fully reversible and nonthermal in nature. Our observations reveal a phase-transition pathway in materials, where electron-induced changes in the electronic structure can lead to a macroscopic reconstruction of the crystal structure.

Matched MeSH terms: Electrons

Displaying publications 41 - 60 of 284 in total