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Search for "scanning electron microscopy" in Full Text gives 60 result(s) in Beilstein Journal of Organic Chemistry.

An alternative to hydrogenation processes. Electrocatalytic hydrogenation of benzophenone

  • Cristina Mozo Mulero,
  • Alfonso Sáez,
  • Jesús Iniesta and
  • Vicente Montiel

Beilstein J. Org. Chem. 2018, 14, 537–546, doi:10.3762/bjoc.14.40

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  • the Pd nanoparticles. Thermogravimetric analysis (TGA) was performed using a Mettler Toledo model TGA/SDTA851 and /SF/1100 using a heating slope of 10 K min−1 from 298 K to 1023 K under a N2:O2 (4:1) atmosphere. For the characterisation of the Pdx/C/T scanning electron microscopy (SEM) micrographs
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Published 01 Mar 2018

New bio-nanocomposites based on iron oxides and polysaccharides applied to oxidation and alkylation reactions

  • Daily Rodríguez-Padrón,
  • Alina M. Balu,
  • Antonio A. Romero and
  • Rafael Luque

Beilstein J. Org. Chem. 2017, 13, 1982–1993, doi:10.3762/bjoc.13.194

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  • three materials (Table 1). The materials exhibited, in general, satisfying surface areas and pore volumes, particularly taking into account their preparation methodology. Electron microscopy The morphology of the nanomaterials was determined by scanning electron microscopy (SEM) and transmission
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Published 21 Sep 2017

Mechanochemical synthesis of graphene oxide-supported transition metal catalysts for the oxidation of isoeugenol to vanillin

  • Ana Franco,
  • Sudipta De,
  • Alina M. Balu,
  • Araceli Garcia and
  • Rafael Luque

Beilstein J. Org. Chem. 2017, 13, 1439–1445, doi:10.3762/bjoc.13.141

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  • diffraction (XRD), transmission electron microscopy (TEM), scanning electron microscopy (SEM) and diffuse reflectance infrared Fourier transform spectroscopy (DRIFT). N2 adsorption measurements were performed at 77 K by using a Micromeritics ASAP 2000 volumetric adsorption analyzer. The samples were degassed
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Published 21 Jul 2017

Continuous-flow processes for the catalytic partial hydrogenation reaction of alkynes

  • Carmen Moreno-Marrodan,
  • Francesca Liguori and
  • Pierluigi Barbaro

Beilstein J. Org. Chem. 2017, 13, 734–754, doi:10.3762/bjoc.13.73

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Published 20 Apr 2017

Fast and efficient synthesis of microporous polymer nanomembranes via light-induced click reaction

  • Qi An,
  • Youssef Hassan,
  • Xiaotong Yan,
  • Peter Krolla-Sidenstein,
  • Tawheed Mohammed,
  • Mathias Lang,
  • Stefan Bräse and
  • Manuel Tsotsalas

Beilstein J. Org. Chem. 2017, 13, 558–563, doi:10.3762/bjoc.13.54

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  • selectively dissolved using cyclohexane. Afterwards we dissolved the sacrificial substrate to obtain the freestanding CMP membranes. To investigate the freestanding CMP nanomembrane we transferred it to a copper grid and recorded scanning electron microscopy (SEM) images. Figure 4 shows the SEM images of the
  • electron microscopy (SEM): We recorded SEM images using a FEI Philips XL30 (FEI Co., Eindhoven, NL), a field emission gun environmental scanning electron microscope (FEG-ESEM). Samples have been coated with a thin layer (about 5 nm) of a gold/palladium film in order to avoid charging and improve samples
  • IRRAS accessory (A518) has a fixed angle of incidence of 80°. The data were collected on a middle band liquid nitrogen cooled MCT detector. Perdeuterated hexadecanethiol-SAMs on Au/Ti/Si were used for reference measurements [32]. The absorption band positions are given in wavenumbers (cm−1). Scanning
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Published 17 Mar 2017

A new class of organogelators based on triphenylmethyl derivatives of primary alcohols: hydrophobic interactions alone can mediate gelation

  • Wangkhem P. Singh and
  • Rajkumar S. Singh

Beilstein J. Org. Chem. 2017, 13, 138–149, doi:10.3762/bjoc.13.17

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  • the gel were carried out using scanning electron microscopy, FTIR spectroscopy, rheology and powder XRD techniques. This gel also showed a good absorption profile for a water soluble dye. Given the non-polar nature of this molecule, gel formation is likely to be mediated by hydrophobic interactions
  • microscopic structures and morphologies of the gels formed by the gelators, scanning electron microscopy (SEM) studies were performed with the dried gels [33]. Dried gels (xerogels) were obtained from the gels by evaporation of the solvent. The morphologies for TPM-G12 and TPM-G5 are drastically different
  • with minimum gelation concentration in the range of 0.5–4.0%, w/v. 1,8-Bis(trityloxy)octane, the ditrityl derivative of 1,8-octanediol was found to be an excellent gelator of some polar solvents. Detailed characterizations of the gel were carried out using scanning electron microscopy, FTIR
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Published 23 Jan 2017

Synthesis of three-dimensional porous hyper-crosslinked polymers via thiol–yne reaction

  • Mathias Lang,
  • Alexandra Schade and
  • Stefan Bräse

Beilstein J. Org. Chem. 2016, 12, 2570–2576, doi:10.3762/bjoc.12.252

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  • crosslinking reaction conditions. The obtained HCPs showed BET surface areas up to 650 m²/g and are insoluble in common organic solvents. The characterisation of the networks was performed using IR spectroscopy, elemental analysis, thermogravimetric analysis (TGA), scanning electron microscopy (SEM), powder X
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Published 29 Nov 2016

Size-controlled and redox-responsive supramolecular nanoparticles

  • Raquel Mejia-Ariza,
  • Gavin A. Kronig and
  • Jurriaan Huskens

Beilstein J. Org. Chem. 2015, 11, 2388–2399, doi:10.3762/bjoc.11.260

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  • ). Equipment Dynamic light scattering (DLS) Hydrodynamic diameters and zeta potentials were measured on a Zetasizer NanoZS (Malvern Instrument Ltd, Malvern, United Kingdom) at 20 °C, with a laser wavelength of 633 nm and a scattering angle of 173°. High resolution scanning electron microscopy (HR-SEM) All SEM
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Published 01 Dec 2015

Preparation of Pickering emulsions through interfacial adsorption by soft cyclodextrin nanogels

  • Shintaro Kawano,
  • Toshiyuki Kida,
  • Mitsuru Akashi,
  • Hirofumi Sato,
  • Motohiro Shizuma and
  • Daisuke Ono

Beilstein J. Org. Chem. 2015, 11, 2355–2364, doi:10.3762/bjoc.11.257

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  • particle size of the primary CD nanogel and the appearance of a new peak at a larger diameter (120 nm) may be due to the self-assembly of the primary CD nanogels at 0.1 wt % concentration in water. The scanning electron microscopy (SEM) measurement was carried out in order to observe the self-assembled
  • solutions, which were ultrafiltered through a 0.8 μm membrane to remove dust. Electron microscopy Scanning electron microscopy (SEM) studies were performed using a field emission gun scanning electron microscope (JSM-6700F, JEOL Ltd., Japan) with a beam current of 10 μA at a typical operating voltage of 15
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Published 30 Nov 2015

Urethane tetrathiafulvalene derivatives: synthesis, self-assembly and electrochemical properties

  • Xiang Sun,
  • Guoqiao Lai,
  • Zhifang Li,
  • Yuwen Ma,
  • Xiao Yuan,
  • Yongjia Shen and
  • Chengyun Wang

Beilstein J. Org. Chem. 2015, 11, 2343–2349, doi:10.3762/bjoc.11.255

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  • Technology of Ministry of Education, Hangzhou Normal University, Hangzhou 310012, China 10.3762/bjoc.11.255 Abstract This paper reports the self-assembly of two new tetrathiafulvalene (TTF) derivatives that contain one or two urethane groups. The formation of nanoribbons was evidenced by scanning electron
  • microscopy (SEM) and X-ray diffraction (XRD), which showed that the self-assembly ability of T1 was better than that of T2. The results revealed that more urethane groups in a molecule did not necessarily instigate self-assembly. UV–vis and FTIR spectra were measured to explore noncovalent interactions. The
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Published 27 Nov 2015

Synthesis of photoresponsive cholesterol-based azobenzene organogels: dependence on different spacer lengths

  • Yuchun Ren,
  • Bin Wang and
  • Xiuqing Zhang

Beilstein J. Org. Chem. 2015, 11, 1089–1095, doi:10.3762/bjoc.11.122

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  • to gel phase transition under visible irradiation. The corresponding visual images are shown in Figure 3. Scanning electron microscopy studies To obtain a visual insight into the morphology of the aggregation mode, the typical structures of the xerogels prepared by the freeze-drying of the three gels
  • spectroscopy (IR) was measured on a Nicolet 6700 spectrometer from 4000 to 500 cm−1 at room temperature. The samples were prepared as KBr pellets. The morphology of the gel samples were examined by scanning electron microscopy (SEM, S5200, FEI Company) under an acceleration voltage of 30 kV. UV–vis absorption
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Published 29 Jun 2015

Carboxylated dithiafulvenes and tetrathiafulvalene vinylogues: synthesis, electronic properties, and complexation with zinc ions

  • Yunfei Wang and
  • Yuming Zhao

Beilstein J. Org. Chem. 2015, 11, 957–965, doi:10.3762/bjoc.11.107

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  • equipped with a copper X-ray source with a wavelength of 1.54 nm. Scanning electron microscopy (SEM) was performed on an FEI MLA 650 FEG microscope. BET surface area and pore size analyses were performed on a Micromeritics TriStar II Plus instrument. The degassing was done on a Flow Prep 060 instrument
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Published 03 Jun 2015

Formulation development, stability and anticancer efficacy of core-shell cyclodextrin nanocapsules for oral chemotherapy with camptothecin

  • Hale Ünal,
  • Naile Öztürk and
  • Erem Bilensoy

Beilstein J. Org. Chem. 2015, 11, 204–212, doi:10.3762/bjoc.11.22

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  • permeability. The CD nanocapsules were imaged by scanning electron microscopy (SEM). The concentration of CPT entrapped in nanocapsules was determined by reversed phase HPLC. The in vitro release study of CPT was performed with a dialysis bag method under sink conditions mimicking the gastric and intestinal pH
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Published 04 Feb 2015

Thermal and oxidative stability of the Ocimum basilicum L. essential oil/β-cyclodextrin supramolecular system

  • Daniel I. Hădărugă,
  • Nicoleta G. Hădărugă,
  • Corina I. Costescu,
  • Ioan David and
  • Alexandra T. Gruia

Beilstein J. Org. Chem. 2014, 10, 2809–2820, doi:10.3762/bjoc.10.298

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  • complexation process, was 74.2%. This relatively high recovery yield for the β-CD complex can be explained by the lower water (as well as ethanol/water) solubility. The quality of the essential oil/β-CD complex formation was sustained by the morphology of the complex crystals, evaluated by scanning electron
  • microscopy, SEM (Inspect S, voltage of 25 kV, magnification of 3000–12000×, focus of 10–14.1 mm; see Supporting Information File 1). Rhombohedral prisms with dimensions up to ten micrometers for O. basilicum L. essential oil/β-CD complex were obtained. The relative concentration of the main compounds of the
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Published 28 Nov 2014

Detonation nanodiamonds biofunctionalization and immobilization to titanium alloy surfaces as first steps towards medical application

  • Juliana P. L. Gonçalves,
  • Afnan Q. Shaikh,
  • Manuela Reitzig,
  • Daria A. Kovalenko,
  • Jan Michael,
  • René Beutner,
  • Gianaurelio Cuniberti,
  • Dieter Scharnweber and
  • Jörg Opitz

Beilstein J. Org. Chem. 2014, 10, 2765–2773, doi:10.3762/bjoc.10.293

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  • -PEA. Immobilization of DND Scanning electron microscopy (SEM) was used to characterize the surface morphology of titanium samples coated with previously functionalized nanodiamonds. DND before and after functionalization were used to evaluate the improvement on the interaction of DND with the titanium
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Published 26 Nov 2014

Improving the reactivity of phenylacetylene macrocycles toward topochemical polymerization by side chains modification

  • Simon Rondeau-Gagné,
  • Jules Roméo Néabo,
  • Maxime Daigle,
  • Katy Cantin and
  • Jean-François Morin

Beilstein J. Org. Chem. 2014, 10, 1613–1619, doi:10.3762/bjoc.10.167

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  • the xerogel state to form polydiacetylenes (PDAs), leading to a significant enhancement of the polymerization yields. The organogels and the PDAs were characterized using Raman spectroscopy, X-ray diffraction (XRD) and scanning electron microscopy (SEM). Keywords: carbon nanomaterials; organogels
  • heating the gel from 223 to 298 K, an endotherm was observed in both cases, which is closely related to the melting point of free cyclohexane [39]. To explore the morphology of the structures created during the gel formation, scanning electron microscopy (SEM) was performed on PAM2 only since PAM3 did not
  • to PAM3. Scanning electron microscopy (SEM) images of PAM2 xerogel in cyclohexane (10 mg/mL). Scales are a) 1 μm and b) 0.5 μm. UV–vis spectrum of PAM2 before (black) and after (red) polymerization (PDA). Background-corrected Raman spectra of PAM2 (red) and the blue material obtained after UV
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Published 15 Jul 2014

Charge-transfer interaction mediated organogels from 18β-glycyrrhetinic acid appended pyrene

  • Jun Hu,
  • Jindan Wu,
  • Qian Wang and
  • Yong Ju

Beilstein J. Org. Chem. 2013, 9, 2877–2885, doi:10.3762/bjoc.9.324

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  • in the formation of CT gels is demonstrated through the formation of gels in a variety of solvents. Thermal stability, stoichiometry, scanning electron microscopy (SEM), optical micrographs, and circular dichroism (CD) are performed on these CT gels to investigate their thermal and assembly
  • acceptor in these CT gels. Microscopic study Generally, it is believed that the gelation system is the result of a gelator network formed during the cooling or shaking process [52]. The morphology of the xerogels obtained from CT gels was investigated by scanning electron microscopy (SEM) in order to
  • -component CT interaction induced an organogel formation based on 18β-glycyrrhetinic acid–pyrene conjugate 3 and 2,4,7-trinitrofluorenone (TNF, 4). Their thermal and assembly properties were studied by thermal stability, stoichiometry, scanning electron microscopy (SEM), optical micrographs, and circular
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Published 16 Dec 2013

Self-assembly of 2,3-dihydroxycholestane steroids into supramolecular organogels as a soft template for the in-situ generation of silicate nanomaterials

  • Valeria C. Edelsztein,
  • Andrea S. Mac Cormack,
  • Matías Ciarlantini and
  • Pablo H. Di Chenna

Beilstein J. Org. Chem. 2013, 9, 1826–1836, doi:10.3762/bjoc.9.213

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  • diffraction measurements: Diffraction patterns were obtained by using a Siemens D5000 diffractometer with Cu Kα radiation (λ = 1.54056 Å), the stepsize was 0.025° with a measurement time of 6 s per step. Scanning electron microscopy: SEM measurements were performed in a similar manner as described in [25
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Published 09 Sep 2013

Molecular assembly of amino acid interlinked, topologically symmetric, π-complementary donor–acceptor–donor triads

  • M. B. Avinash,
  • K. V. Sandeepa and
  • T. Govindaraju

Beilstein J. Org. Chem. 2013, 9, 1565–1571, doi:10.3762/bjoc.9.178

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  • strong aromatic stacking (see Supporting Information File 1). Remarkably 1, 2 and 3 form free floating aggregates within a couple of hours in aqueous DMSO and aqueous NMP (Figure 2). These free floating aggregates were subjected to morphological studies using field emission scanning electron microscopy
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Published 01 Aug 2013

Simple and rapid hydrogenation of p-nitrophenol with aqueous formic acid in catalytic flow reactors

  • Rahat Javaid,
  • Shin-ichiro Kawasaki,
  • Akira Suzuki and
  • Toshishige M. Suzuki

Beilstein J. Org. Chem. 2013, 9, 1156–1163, doi:10.3762/bjoc.9.129

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  • emission spectroscopy (ICP–AES, Model SPS 3100; SII Nano Technology Inc.). The morphology of the inner surface of the catalytic tubular reactors was observed by scanning electron microscopy (SEM) equipped with an energy-dispersive X-ray spectrometer (EDX, XL30S; Philips Co.). UV–vis absorption spectra were
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Published 14 Jun 2013

C–C Bond formation catalyzed by natural gelatin and collagen proteins

  • Dennis Kühbeck,
  • Basab Bijayi Dhar,
  • Eva-Maria Schön,
  • Carlos Cativiela,
  • Vicente Gotor-Fernández and
  • David Díaz Díaz

Beilstein J. Org. Chem. 2013, 9, 1111–1118, doi:10.3762/bjoc.9.123

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  • -emission scanning electron microscopy (FESEM) images of the biocatalysts associated faster reactions with porous fibrilar morphologies and slower kinetics with thicker and close-grained surfaces (Figure 3). These results suggest that the morphology and/or physical state of the proteins play an important
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Published 07 Jun 2013

A peptidic hydrogel that may behave as a “Trojan Horse”

  • Nicola Castellucci,
  • Giorgio Sartor,
  • Natalia Calonghi,
  • Carola Parolin,
  • Giuseppe Falini and
  • Claudia Tomasini

Beilstein J. Org. Chem. 2013, 9, 417–424, doi:10.3762/bjoc.9.44

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  • , were analyzed by X-ray diffraction (XRD) and scanning electron microscopy (SEM). Hydrogel 1 is a strong and thermoreversible gel (Figure 1a) with its melting point at 45 °C. The XRD pattern from the hydrogel 1, collected at 100 K, is characterized by the presence of diffraction rings at low angle
  • (OM) and scanning electron microscopy (SEM), respectively. The OM images were collected by using an optical microscope (Leica) equipped with a CCD camera. SEM images of xerogels were collected after gluing the samples on a carbon tape and observed directly in a Phenom microscope (FEI) without any
  • ) Scanning electron microscopy images of a xerogel 1 film fragment. In the inset a low magnification view of the xerogel film fragments is shown. (b) Powder XRD pattern of a powered sample of xerogel 1. Low–medium-angle XRD patterns obtained in geometries having the X-ray beam normal (c) and parallel (d) to
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Published 22 Feb 2013

Spin state switching in iron coordination compounds

  • Philipp Gütlich,
  • Ana B. Gaspar and
  • Yann Garcia

Beilstein J. Org. Chem. 2013, 9, 342–391, doi:10.3762/bjoc.9.39

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Published 15 Feb 2013

Self-assembled organic–inorganic magnetic hybrid adsorbent ferrite based on cyclodextrin nanoparticles

  • Ângelo M. L. Denadai,
  • Frederico B. De Sousa,
  • Joel J. Passos,
  • Fernando C. Guatimosim,
  • Kirla D. Barbosa,
  • Ana E. Burgos,
  • Fernando Castro de Oliveira,
  • Jeann C. da Silva,
  • Bernardo R. A. Neves,
  • Nelcy D. S. Mohallem and
  • Rubén D. Sinisterra

Beilstein J. Org. Chem. 2012, 8, 1867–1876, doi:10.3762/bjoc.8.215

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  • . Solid magnetic materials obtained were washed with hot distilled water and filtered, and then the freeze-dried material was used in the solid-state characterization. Part of the ferrite was kept in water to investigate the properties of the aqueous suspension. Microscopy analysis Scanning electron
  • microscopy (SEM) was performed in a JEOL, JSM 840A at 4–10 KV in which samples were covered with a thin gold layer, for electronic contrast. Transmission electron microscopy (TEM) images were obtained in a FEI TECNAI G2 with a thermo-ionic gun at 200 kV. Atomic force microscopy (AFM) images were obtained
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Published 01 Nov 2012

Control over molecular motion using the cistrans photoisomerization of the azo group

  • Estíbaliz Merino and
  • María Ribagorda

Beilstein J. Org. Chem. 2012, 8, 1071–1090, doi:10.3762/bjoc.8.119

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  • capable of holding other molecules. The isomerization process of azobenzene generates a molecular flapping and the molecules can be expelled outside in a photoinduced way. The morphology of the light-activated mesostructured silica nanoparticles (LAMs) is evaluated by scanning electron microscopy (SEM
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Published 12 Jul 2012
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