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Search for "SEM" in Full Text gives 103 result(s) in Beilstein Journal of Organic Chemistry.

A systematic review on silica-, carbon-, and magnetic materials-supported copper species as efficient heterogeneous nanocatalysts in “click” reactions

  • Pezhman Shiri and
  • Jasem Aboonajmi

Beilstein J. Org. Chem. 2020, 16, 551–586, doi:10.3762/bjoc.16.52

Graphical Abstract
  • ), respectively (Scheme 1). The catalysts were characterized by a series of analytical techniques. The solid-state 13C NMR of IPSi showed nine peaks at 10, 24, 43, 63, 121, 136, 148, 155, and 162 ppm, respectively. SEM analysis displayed an irregular shape for 1a and 1b. The catalytic activity of Cu(I)@IPSi (1a
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Published 01 Apr 2020

Influence of the cis/trans configuration on the supramolecular aggregation of aryltriazoles

  • Sara Tejera,
  • Giada Caniglia,
  • Rosa L. Dorta,
  • Andrea Favero,
  • Javier González-Platas and
  • Jesús T. Vázquez

Beilstein J. Org. Chem. 2019, 15, 2881–2888, doi:10.3762/bjoc.15.282

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  • - and cis-1,2-glucopyranosyl and cyclohexyl ditriazoles, synthesized by CuAAC "click" chemistry, to form gels was studied, their physical properties determined, and the self-aggregation behavior investigated by SEM, X-ray, and EDC studies. The results revealed that self-assembly was driven mainly by π–π
  • , and 14 were obtained by SEM (Figure 2). Analyses of these images revealed typically fibrous networks for all except 10. Compound 7f (trans) showed a dense, thin, short, and interlaced/tangled fiber network. The corresponding α-anomer 8f (cis) exhibited an irregular, porous, and dense structure having
  • and distilled before use. ECD was recorded in the range of 200–400 nm at room temperature by using 10 mm quartz cells. SEM images were taken by a TEM, JEOL JEM 1010 belonging to the Electronic Microscopy Service (SEGAI) of the University of La Laguna, Spain. Compounds 7f, 8f, 9, 10, 11, and 12 were
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Published 28 Nov 2019

Carbazole-functionalized hyper-cross-linked polymers for CO2 uptake based on Friedel–Crafts polymerization on 9-phenylcarbazole

  • Dandan Fang,
  • Xiaodong Li,
  • Meishuai Zou,
  • Xiaoyan Guo and
  • Aijuan Zhang

Beilstein J. Org. Chem. 2019, 15, 2856–2863, doi:10.3762/bjoc.15.279

Graphical Abstract
  • the temperature raised up to 800 °C (Supporting Information File 1, Table S1), demonstrated the splendid thermal stability of P1–P11 as reported for microporous polymers [34]. Morphology analysis The morphology of P1–P11 was investigated by SEM images (Figure 4), which showed that HCPs were composed
  • 0.0202°, 2θ ranging from 5.0 to 60°. Scanning electron microscope (SEM) measurements of obtained samples were carried out using a Hitachi SU1510 microscope. The nitrogen adsorption and desorption and the CO2 adsorption and desorption isotherms of HCPs were obtained using a GAPP V-Sorb 2800P BET surface
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Published 26 Nov 2019

Palladium-catalyzed synthesis and nucleotide pyrophosphatase inhibition of benzo[4,5]furo[3,2-b]indoles

  • Hoang Huy Do,
  • Saif Ullah,
  • Alexander Villinger,
  • Joanna Lecka,
  • Jean Sévigny,
  • Peter Ehlers,
  • Jamshed Iqbal and
  • Peter Langer

Beilstein J. Org. Chem. 2019, 15, 2830–2839, doi:10.3762/bjoc.15.276

Graphical Abstract
  • nucleotide pyrophosphatase enzyme h-NPP-3. In case of 5e, an inhibitory value IC50 ± SEM = 0.26 ± 0.01 µM was observed which, thus, might be considered as potential inhibitor of h-NPP-3. Compound 5c with an inhibitory value for h-NPP-1 of IC50 ± SEM = 1.29 ± 0.07 µM was more active against NPP1 than against
  • towards h-NPP-3 (IC50 ± SEM = 0.13 ± 0.06 and 0.28 ± 0.04, respectively). In fact, they had no interaction with enzyme h-NPP-1. Compound 6a, containing a tolyl group, was active against both h-NPP-1 and h-NPP-3, but was more selective to h-NPP-1 with an inhibitory value of IC50 ± SEM = 0.11 ± 0.06 µM. In
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Published 22 Nov 2019

Chemical tuning of photoswitchable azobenzenes: a photopharmacological case study using nicotinic transmission

  • Lorenzo Sansalone,
  • Jun Zhao,
  • Matthew T. Richers and
  • Graham C. R. Ellis-Davies

Beilstein J. Org. Chem. 2019, 15, 2812–2821, doi:10.3762/bjoc.15.274

Graphical Abstract
  • (530 nm, 3 mW) or 1 s violet light (405 nm, 10 mW). Data were analyzed in Patchmaster software (Heka). The amplitudes of currents were calculated as the difference of the peak and baseline. All data were present as the mean ± SEM. One-way ANOVA was used to determine whether there are any statistically
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Published 21 Nov 2019

Synthesis of novel sulfide-based cyclic peptidomimetic analogues to solonamides

  • José Brango-Vanegas,
  • Luan A. Martinho,
  • Lucinda J. Bessa,
  • Andreanne G. Vasconcelos,
  • Alexandra Plácido,
  • Alex L. Pereira,
  • José R. S. A. Leite and
  • Angelo H. L. Machado

Beilstein J. Org. Chem. 2019, 15, 2544–2551, doi:10.3762/bjoc.15.247

Graphical Abstract
  • represent standard deviations. Cell viability of human fibroblast exposed to compounds 9e (A) and 9g (B) for 24 and 48 hours. The values are expressed as mean ± SEM. ****p < 0.0001, **p < 0.005 and ***p < 0.001 versus DMEM control group. Macrocyclization strategy based on SN2’. Chemical synthesis of the MBH
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Published 25 Oct 2019

A toolbox of molecular photoswitches to modulate the CXCR3 chemokine receptor with light

  • Xavier Gómez-Santacana,
  • Sabrina M. de Munnik,
  • Tamara A. M. Mocking,
  • Niels J. Hauwert,
  • Shanliang Sun,
  • Prashanna Vijayachandran,
  • Iwan J. P. de Esch,
  • Henry F. Vischer,
  • Maikel Wijtmans and
  • Rob Leurs

Beilstein J. Org. Chem. 2019, 15, 2509–2523, doi:10.3762/bjoc.15.244

Graphical Abstract
  • a competition binding assay versus displacement of a radiolabeled small-molecule CXCR3 antagonist ([3H]-VUF11211 [31]). Values reported are mean ± SEM (Standard Error of the Mean). These experiments were performed with samples under dark conditions to ensure ≥99% trans-isomer and with samples
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Published 23 Oct 2019

Archangelolide: A sesquiterpene lactone with immunobiological potential from Laserpitium archangelica

  • Silvie Rimpelová,
  • Michal Jurášek,
  • Lucie Peterková,
  • Jiří Bejček,
  • Vojtěch Spiwok,
  • Miloš Majdl,
  • Michal Jirásko,
  • Miloš Buděšínský,
  • Juraj Harmatha,
  • Eva Kmoníčková,
  • Pavel Drašar and
  • Tomáš Ruml

Beilstein J. Org. Chem. 2019, 15, 1933–1944, doi:10.3762/bjoc.15.189

Graphical Abstract
  • were used as control. All experiments were done in quadruplicates. The data were analyzed in Microsoft Excel; the deviations were calculated as standard error of the mean (SEM). For primary peritoneal cells, a slightly modified procedure was used: the number of 1·105 cells per well was cultivated
  • and 40 µM concentrations and cells were cultured for 24 h. WST-1 assay was used for viability evaluation. The results are expressed as percentage of untreated control ± SEM of n = 6–8 values from two independent experiments. Statistical significance: *P < 0.05, the results of compound 5 are
  • . The results represent the mean ± SEM of three independent experiments, n = 6. Statistical significance: * P < 0.01, **P < 0.001, the results of the compounds are statistically different from those of the LPS-treated cells. Evaluation of cytokine TNF-α secretion in rat peritoneal cells. Stimulation of
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Published 13 Aug 2019

A heteroditopic macrocycle as organocatalytic nanoreactor for pyrroloacridinone synthesis in water

  • Piyali Sarkar,
  • Sayan Sarkar and
  • Pradyut Ghosh

Beilstein J. Org. Chem. 2019, 15, 1505–1514, doi:10.3762/bjoc.15.152

Graphical Abstract
  • subjected to various studies like SEM, TEM and DLS experiments. The DLS data revealed that the dispersed particles size in the aqueous phase varied from ≈60 nm to ≈105 nm (Figure 2a). Interestingly, when the same dispersion was used for the analysis of the particle size distribution on a solid surface, i.e
  • ., in SEM and TEM, the diameters were also found to be in the range of 70–100 nm (Figure 2b and 2c). So, these studies supported the nanoranged dispersion of the macrocycle, which indeed follows the basic characteristic of a nanoreactor. Optimization of the reaction conditions for the synthesis of
  • . Therefore, BATA-MC has the prospective of reworking at least five times. SEM and TEM images of the catalyst’s nanoranged dispersive particles after five cycles are given in Supporting Information File 1 (Figure S4) which confirm the range of particle sizes of 70–110 nm even after five cycles. Conclusion In
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Published 08 Jul 2019

Reaction of oxiranes with cyclodextrins under high-energy ball-milling conditions

  • László Jicsinszky,
  • Federica Calsolaro,
  • Katia Martina,
  • Fabio Bucciol,
  • Maela Manzoli and
  • Giancarlo Cravotto

Beilstein J. Org. Chem. 2019, 15, 1448–1459, doi:10.3762/bjoc.15.145

Graphical Abstract
  • -sodium salts were cooled below −30 °C with liquid nitrogen before the addition of the reagents. Jar-temperature changes during the reaction of 1,2-propylene oxide and cyclodextrins in the presence of NaOH. Comparative SEM pictures of a β-CD bead and β-CDP (20 mmol, Table 3, entry 10). Comparison of β-CDP
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Published 01 Jul 2019

Mechanochemical synthesis of hyper-crosslinked polymers: influences on their pore structure and adsorption behaviour for organic vapors

  • Sven Grätz,
  • Sebastian Zink,
  • Hanna Kraffczyk,
  • Marcus Rose and
  • Lars Borchardt

Beilstein J. Org. Chem. 2019, 15, 1154–1161, doi:10.3762/bjoc.15.112

Graphical Abstract
  • Information File 1, Figure S2) at around 310 °C. The residual mass of only 1.9% confirms the absence of both, excessive abrasion and oxidant inside the polymer. This is further supported by the SEM-EDX (scattering electron microscope, energy-dispersive X-ray spectroscopy) measurements showing both Cl and Fe
  • . Scanning electron microscopy (SEM/EDX) images were obtained using a Hitachi SU8020 SEM equipped with a secondary electron (SE) detector. Prior to the measurement the samples were prepared on an adhesive carbon pad and sputtered with gold to obtain the necessary electron conductivity. Thermogravimetric
  • acknowledge the Federal Ministry of Education and Research (Bundesministerium für Bildung und Forschung, BMBF, award number 03SF0498) and the DECHEMA (Max-Buchner Forschungsstipendium) for financial support. The authors acknowledge Sebastian Ehrling for the SEM/EDX measurements. MR gratefully acknowledges
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Published 24 May 2019

Stereo- and regioselective hydroboration of 1-exo-methylene pyranoses: discovery of aryltriazolylmethyl C-galactopyranosides as selective galectin-1 inhibitors

  • Alexander Dahlqvist,
  • Axel Furevi,
  • Niklas Warlin,
  • Hakon Leffler and
  • Ulf J. Nilsson

Beilstein J. Org. Chem. 2019, 15, 1046–1060, doi:10.3762/bjoc.15.102

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Published 07 May 2019

A chemically contiguous hapten approach for a heroin–fentanyl vaccine

  • Yoshihiro Natori,
  • Candy S. Hwang,
  • Lucy Lin,
  • Lauren C. Smith,
  • Bin Zhou and
  • Kim D. Janda

Beilstein J. Org. Chem. 2019, 15, 1020–1031, doi:10.3762/bjoc.15.100

Graphical Abstract
  • bleed schedule. Summary of behavioral data for most promising chemically contiguous vaccine HF-7, compared to singular hapten-vaccines and controls. A) Structures of haptens; B) ED50 values for heroin and fentanyl; C) potency values. Bars represent means + SEM. Summary of behavioral data for phenethyl
  • -linked haptens HF-4 and HF-6. Bars represent mean ± SEM. Correlation plots of dual hapten vaccines comparing week 5 and 8 ELISA midpoint titers to ED50 values. Linear regression analysis was performed and R2 values for week 8 are A) heroin week 8 R2 = 0.7803; B) fentanyl week 8 R2 = 0.3459; C) 10
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Published 03 May 2019

Fabrication, characterization and adsorption properties of cucurbit[7]uril-functionalized polycaprolactone electrospun nanofibrous membranes

  • Changzhong Chen,
  • Fengbo Liu,
  • Xiongzhi Zhang,
  • Zhiyong Zhao and
  • Simin Liu

Beilstein J. Org. Chem. 2019, 15, 992–999, doi:10.3762/bjoc.15.97

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  • , Xiangnan University, Chenzhou 423000, China 10.3762/bjoc.15.97 Abstract The fabrication of electrospun nanofibers comprising cucurbit[7]uril (CB[7]) and poly(ε-caprolactone) (PCL) is reported. Various techniques such as SEM, FTIR, XRD, DSC and TG were utilized to characterize the morphology, composition
  • morphology of the PCL/CB[5], PCL/CB[6], and PCL/CB[8] composite nanofibers as observed by SEM are supplied in Supporting Information File 1 (Figures S2–S4). In contrast, CB[7] was quite soluble in formic acid and the maximum CB[7] mass percentage in the composite nanofibers could be up to 66.67% (the mass
  • ratio of PCL/CB[7] is 100:200), which is far higher than the CDs content in CD-functionalized nanofibers [13][14][15] and the calixarene content in the calixarene-functionalized nanofibers [20]. Figure 1 presents the SEM photographs and fiber diameter distributions of neat PCL and the PCL/CB[7
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Published 29 Apr 2019

Fabrication of supramolecular cyclodextrin–fullerene nonwovens by electrospinning

  • Hiroaki Yoshida,
  • Ken Kikuta and
  • Toshiyuki Kida

Beilstein J. Org. Chem. 2019, 15, 89–95, doi:10.3762/bjoc.15.10

Graphical Abstract
  • the color strength is clearly related with the C60 concentration in the complex solution used for electrospinning. This is completely different from the white γ-CD nonwovens without C60 (Figure 3a–c). SEM observations clearly suggest that the microstructure of the samples are the almost same
  • between the cannula and the substrate. Nonwovens were prepared after 1 hour of electrospinning. The obtained nonwovens were evaluated by SEM (JSM-6010LA, JEOL, Japan), UV–vis diffuse reflectance spectrum (V-670 spectrometer with an integration sphere attachment, JASCO), 13C CP/MAS NMR spectrum (Bruker
  • . (d) UV–vis absorbance of the final solution vs feed C60 amount (0.6, 3.2, 16, 40, 80 mg mL−1, n = 3). Fabrication of γ-CD–C60 inclusion complex nonwovens by electrospinning. Photographs and SEM images of (a) γ-CD–C60 nonwoven ([C60] = 1.5 × 10−2 M), (b) γ-CD–C60 nonwoven ([C60] = 2.6 × 10−3 M), and
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Published 09 Jan 2019

MoO3 on zeolites MCM-22, MCM-56 and 2D-MFI as catalysts for 1-octene metathesis

  • Hynek Balcar,
  • Martin Kubů,
  • Naděžda Žilková and
  • Mariya Shamzhy

Beilstein J. Org. Chem. 2018, 14, 2931–2939, doi:10.3762/bjoc.14.272

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  • cross metathesis was even higher (the selectivity to tetradecene was only 15%). The crystals of MCM-22 (see SEM image in Supporting Information File 1, Figure S7) consist of very thin platelets and therefore a great amounts of 12-membered ring cups of MWW structure are on crystal exterior [18]. These
  • ). Molybdenum(VI) oxide (Sigma-Aldrich) and bis(acetylacetonato)dioxomolybdenum(VI) (Aldrich) as sources of Mo oxide species were used for catalyst preparation using the thermal spreading method (500 °C, 8 h). SEM images were recorded using a JEOL JSM-5500LV microscope. The concentrations of Lewis (cL) and
  • metathesis over MCM-22(70)-based catalysts.a Supporting Information Supporting Information File 296: IR spectra of catalysts, GC of reaction products, and SEM images of catalysts. Acknowledgements The authors thank J. Přech (J. Heyrovský Institute) for the preparation of MFI support samples, and Valeryia
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Published 27 Nov 2018
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  • minutes at 70 °C, a dark green soiled salt was obtained in 98% yield. The catalyst was characterized by different analyses. The FE-SEM images exhibited that the particles of the catalyst are in nano size. According to XRD pattern, the crystallite size is at about 13.7 nm. The IR spectrum confirmed the
  • 2900 cm−1 and 3400 cm−1 were the evidence of phenylic C–H bond and N–H stretching of carbazole, respectively. Peaks at 1022 cm−1 and 1039 cm−1 corresponded to additional crosslinking during the sulfonation process. The catalyst was investigated by BET, SEM, TEM, and TGA-DTA, as well. The BET surface
  • area decreased from 913 m2 g−1 to 346 m2g−1 during the sulfonation process. The SEM images of HMP-1 (113) and HMP-1-SO3H (114) showed spherical particles. According to the TGA-DTA plot, HMP-1-SO3H (114) is less stable than HMP-1 (113). The resulted catalyst was tested in biodiesel synthesis at room
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Published 01 Nov 2018

A self-assembled photoresponsive gel consisting of chiral nanofibers

  • Lei Zou,
  • Dan Han,
  • Zhiyi Yuan,
  • Dongdong Chang and
  • Xiang Ma

Beilstein J. Org. Chem. 2018, 14, 1994–2001, doi:10.3762/bjoc.14.174

Graphical Abstract
  • microscopy (SEM, Figure 4). The samples were prepared by evaporating the solution of compound 3 on a surface of mica, and the differences in various solvents were also investigated. The sample in DMSO did not show a chiral self-assembled nanostructure owing to the destruction of quadruple hydrogen bonding
  • investigated by drying the chloroform solution of compound 3, which was exposed to sufficient UV light (365 nm) beforehand, on the surface of mica and detected by SEM, whereby only small discs were found as shown in Figure 4b. This implies that the UV light of 365 nm can efficiently destroy the self-assembled
  • was 1.0 × 10−5 M in CHCl3. CD spectrum of compound 3 in solutions of a) benzene, toluene, p-xylene, chloroform, tetrachloromethane and DMSO with identical concentration (3.0 × 10−5 M), b) before and after being exposed to UV (λ = 365 nm) and visible (λ = 420 nm) light. SEM images of the microstructure
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Published 01 Aug 2018

Hyper-reticulated calixarene polymers: a new example of entirely synthetic nanosponge materials

  • Alberto Spinella,
  • Marco Russo,
  • Antonella Di Vincenzo,
  • Delia Chillura Martino and
  • Paolo Lo Meo

Beilstein J. Org. Chem. 2018, 14, 1498–1507, doi:10.3762/bjoc.14.127

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  • was assessed by means of FTIR and 13C{1H} CP-MAS solid-state NMR techniques, whereas morphological characterization was provided by SEM microghaphy. The materials were proved to possess pH-dependent sequestration abilities, due to the presence of the weakly basic triazole linkers. Sequestration
  • different alkyl diazides A1–A4 (Scheme 1b), in which the two azido groups are separated by spacers having different length and rigidity. The materials obtained were characterized by means of combined spectroscopic (FTIR, solid state 13C{1H} CP-MAS NMR), calorimetric (DSC) and imaging (SEM) techniques. Then
  • the CuAAC coupling reaction to proceed up to a lesser extent during the polymer network formation process. SEM and DSC characterization Morphological characterization of the materials was accomplished by means of SEM techniques. A selection of micrographs is reported in Figure 3. The materials show
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Published 20 Jun 2018

Cobalt–metalloid alloys for electrochemical oxidation of 5-hydroxymethylfurfural as an alternative anode reaction in lieu of oxygen evolution during water splitting

  • Jonas Weidner,
  • Stefan Barwe,
  • Kirill Sliozberg,
  • Stefan Piontek,
  • Justus Masa,
  • Ulf-Peter Apfel and
  • Wolfgang Schuhmann

Beilstein J. Org. Chem. 2018, 14, 1436–1445, doi:10.3762/bjoc.14.121

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  • photographs in Figure S3 (Supporting Information File 1) show the contrast of the bare NF and the CoB-modified NF, while Figure S4 (Supporting Information File 1) shows scanning electron (SEM) micrographs of CoB-modified NF. The initially smooth NF surface (Figure 3a,b) appears rough with nanometer sized
  • dilution with 990 μL water. Physical characterization X-ray diffractometry XRD data were obtained using a Panalytical X'PERT Pro MPD X-ray diffractometer with a Cu Kα radiation source (λ = 1.5418 Å) in the 2θ = 20–80° range. Scanning electron microscopy SEM images were taken using a Quanta ED FEG scanning
  • electron microscope (FEI). The SEM was operated at 20 kV. XRD patterns of Co2Si, CoTe, CoAs. Cobalt is indicated by (+) and signals corresponding to the desired materials are indicated by (*). Linear sweep voltammograms of CoP, CoB, CoTe, Co2Si, CoAs modified and blank Ni RDEs for the OER (a) and the HMF
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Published 13 Jun 2018

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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  • characterised by SEM and cyclic voltammetry. A Pd/C to Nafion ratio was established at 60:40 for each electrocatalytic layer irrespectively of the Pd loading in the electrocatalytic layer. Figure 2 depicts the SEM micrographics using back scattering electrons for both Pd0.02/C/T and Pd0.20/C/T electrodes
  • (nomenclature described in the experimental section) at different magnifications. The SEM image for the highest electrocatalytic loading discloses a brighter appearance compared to the lowest one since backscattering electrons from high atomic weight (e.g., palladium) are brighter than lower atomic weight (e.g
  • ., carbon). Apart from the SEM characterisation, the determination of the electrochemically active surface area (ESA) of the cathodic electrocatalytic layer is also crucial for the characterisation of both electrodes. In this regard, Figure 3 depicts the electrochemical behaviour of a Pd0.20/C/T electrode
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Published 01 Mar 2018

Novel approach to hydroxy-group-containing porous organic polymers from bisphenol A

  • Tao Wang,
  • Yan-Chao Zhao,
  • Li-Min Zhang,
  • Yi Cui,
  • Chang-Shan Zhang and
  • Bao-Hang Han

Beilstein J. Org. Chem. 2017, 13, 2131–2137, doi:10.3762/bjoc.13.211

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  • of bisphenol-A-based porous organic polymers. Porosity properties of PPOP-1–PPOP-3. Gas adsorption uptake of PPOP-1–PPOP-3. Supporting Information Supporting Information File 318: Experimental, instruments section, SEM images, data of TGA, FTIR and BET surface area, virial analysis of the adsorption
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Published 12 Oct 2017

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
  • electron microscopy (TEM). The micrographs show a homogeneous distribution of iron oxide nanoparticles for the three catalysts (Figure 3A,C,E). The analysis of the SEM images reveals the tendency of the constituent particles of the magnetic material to form agglomerates due to their nanometer size (Figure
  • 300 °C under air and kept at that temperature for 30 min. Material characterization In order to characterize the synthesized materials, several techniques have been employed, including XRD, XPS, absorption–desorption of N2, SEM, TEM, DRIFT and titrations with pyridine and dimethylpyridine. In addition
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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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  • were characterized by using several techniques including BET, SEM, TEM, XRD, and IR spectroscopy. N2 adsorption/desorption isotherms of the reduced graphene sample (Figure 1a) can be classified as type IV corresponding to the mesoporous materials. The RGO sample showed a BET surface area of 103 m2 g−1
  • decreased, with increased pore diameter and pore volume as a consequence of the structure deterioration observed after milling. Additional macroporosity (interparticular) was created upon milling, which increased both pore diameter and volume. SEM results also support the observation from BET analysis. The
  • mesoporous nature of the RGO can be easily observed from SEM images (Figure 2a and b), whereas metal-supported RGO materials show a smooth surface with decreased crystallinity. TEM images of RGO materials with different thickness show a sheet like morphology with different transparencies (Figure 3). Dark
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Published 21 Jul 2017

Mechanochemistry-assisted synthesis of hierarchical porous carbons applied as supercapacitors

  • Desirée Leistenschneider,
  • Nicolas Jäckel,
  • Felix Hippauf,
  • Volker Presser and
  • Lars Borchardt

Beilstein J. Org. Chem. 2017, 13, 1332–1341, doi:10.3762/bjoc.13.130

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  • ) isopropoxide (Polymer-SF-3, orange). SEM (A) and TEM (B) images of the Carb-SF-3 sample. XRD-pattern of the polymeric precursor (Polymer-SF-3, orange), the carbonized composite (Comp-SF-3, black) and the carbon received by chlorine treatment (Carb-SF-3, red). Nitrogen physisorption isotherms for carbon samples
  • the TEM as well as Sebastian Ehrling for the SEM/EDX measurements. NJ and VP thank Prof. Eduard Arzt (INM) for his continuing support and Aura Tolosa (INM) for discussions.
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Published 06 Jul 2017
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