Enhancing extraordinary transmission of light through a metallic nano slit with a nano cavity antenna

The extraordinary transmission of light through a nano slit in a metal film is enhanced by introducing a nano cavity antenna formed by a nearby metallic nano-strip over the slit opening. For a fixed wavelength, the width of the metallic nano-strip should be chosen to make the horizontal metal-insulator-metal waveguide of finite length resonant as a Fabry-Perot cavity. When such a cavity antenna is used to enhance the transmission through a non-resonant nano slit, the slit should be opened at a position with maximal magnetic field in the horizontal resonant cavity. It is shown that an optimized cavity antenna can enhance greatly the transmission of light through a non-resonant nano slit (by about 20 times) or a resonant nano slit (by 124%). The transmission spectrum of the nano slit can also be tuned by adjusting the width of the metallic nano-strip. Such a transmission enhancement with a nano cavity antenna is studied for the first time and the physical mechanism is explained.Comment: 4 pages, 5 figure

Mirror matter admixtures in K_L \to \gamma\gamma

Based on possible albeit tiny, admixtures of mirror matter in ordinary mesons we study the K_L \to \gamma\gamma transition. We find that this process can be described with a small SU(3) symmetry breaking of only 3%. We also determine the eta-eta' mixing angle and the pseudoscalar decay constants. The results for these parameters are consistent with some obtained in the literature. They favor two recent determinations; one based on two analytical constraints, and another one based on next-to-leading order power corrections

Optimal error bounds for two-grid schemes applied to the Navier-Stokes equations

We consider two-grid mixed-finite element schemes for the spatial discretization of the incompressible Navier-Stokes equations. A standard mixed-finite element method is applied over the coarse grid to approximate the nonlinear Navier-Stokes equations while a linear evolutionary problem is solved over the fine grid. The previously computed Galerkin approximation to the velocity is used to linearize the convective term. For the analysis we take into account the lack of regularity of the solutions of the Navier-Stokes equations at the initial time in the absence of nonlocal compatibility conditions of the data. Optimal error bounds are obtained

Quality Improvement of Few-Layers Defective Graphene from Biomass and Application for H-2 Generation

[EN] Pyrolysis of filmogenic natural polymers gives rise to the formation of films of few-layers defective, undoped, and doped graphenes with low electrical conductivity (3000 to 5000 ohm /sq). For the sake of valorization of biomass wastes, it would be of interest to decrease the density of structural defects in order to increase the conductivity of the resulting few-layers graphene samples. In the present study, analytical and spectroscopic evidence is provided showing that by performing the pyrolysis at the optimal temperature (1100 degrees C), under a low percentage of H-2, a significant decrease in the density of defects related to the presence of residual oxygen can be achieved. This improvement in the quality of the resulting few-layers defective graphene is reflected in a decrease by a factor of about 3 or 5 for alginic acid and chitosan, respectively, of the electrical resistance. Under optimal conditions, few-layers defective graphene films with a resistance of 1000 ohm /sq were achieved. The electrode made of high-quality graphene prepared at 1100 degrees C under Ar/H-2 achieved a H-2 production of 3.62 mu mol with a positive applied bias of 1.1 V under LED illumination for 16 h.Financial support by the Spanish Ministry of Economy and Competitiveness (Severo Ochoa and RTI2018-098237-B-C21) and Generalitat Valencia (Prometeo 2017/083) is gratefully acknowledged. J. H. thanks the Chinese Scholarship Council (CSC) for supporting his doctoral stage at Valencia. A. P. also acknowledges the Spanish Ministry of Economy and Competitiveness for a Ramon y Cajal research associate contract.He, J.; Anouar, A.; Primo Arnau, AM.; García Gómez, H. (2019). Quality Improvement of Few-Layers Defective Graphene from Biomass and Application for H-2 Generation. Nanomaterials. 9(6):1-15. https://doi.org/10.3390/nano9060895S1159

Particle growing mechanisms in Ag-ZrO2 and Au-ZrO2 granular films obtained by pulsed laser deposition

Thin films consisting of Ag and Au nanoparticles embedded in amorphous ZrO2 matrix were grown by pulsed laser deposition in a wide range of metal volume concentrations in the dielectric regime (0.08<x(Ag)<0.28 and 0.08<x(Au)<0.52). High resolution transmission electron microscopy (TEM) showed regular distribution of spherical Au and Ag nanoparticles having very sharp interfaces with the amorphous matrix. Mean particle size determined from X-ray diffraction agreed with direct TEM observation. The silver mean diameter increases more abruptly with metal volume content than that corresponding to gold particles prepared under the same conditions. Two mechanisms of particle growing are observed: nucleation and particle coalescence, their relative significance being different in both granular systems, which yields very different values of the percolation threshold (xc(Ag)~0.28 and xc(Au)~0.52).Comment: 6 figure

Iron Nanoparticles Embedded in Graphitic Carbon Matrix as Heterogeneous Catalysts for the Oxidative C-N Coupling of Aromatic N-H Compounds and Amides

[EN] Fe or Co nanoparticles (NPs) and two nanoparticulate Fe-Co alloys having different Fe/Co atomic ratio with average particle size ranging from 10.9 to 26.5 nm embedded in turbostratic graphitic carbon matrix have been prepared by pyrolysis at 900 degrees C under inert atmosphere of chitosan powders containing Fe2+ and Co2+ ions in various proportions. The resulting Fe/CoNP@C samples have been evaluated as heterogeneous catalysts for the oxidative C-N coupling of amides and aromatic N-H compounds. It was observed that sequential addition of two aliquots of tert-butyl hydroperoxide (TBHP) in an excess of N, N-dimethylacetamide (DMA) as solvent affords the corresponding coupling product in high yields, and the most efficient catalyst was FeNP@C. FeNP@C is reusable and exhibits a wide scope. The catalytic activity of Fe is supported by using highly pure Fe salt and by the observation that purposely addition of Cu2+ impurities even plays a detrimental effect on the catalytic activity. Mechanistic studies by quenching with 2,2,6,6-tetramethylpiperidyl-1-oxyl (TEMPO) have shown that the amide radical is the key reaction intermediate, and the role of FeNP@C is to generate the first radicals by TBHP decomposition.Financial support by the Spanish Ministry of Economy and Competitiveness (Severo Ochoa and CTQ2015-69153-CO2-1) and Generalitat Valenciana (Prometeo 2013-014) is gratefully acknowledged. J.H. thanks the Chinese Scholarship Council for a doctoral fellowship at Valencia. A.D.M. thanks University Grants Commission, New Delhi, for the award of Assistant Professorship under its Faculty Recharge Program. A.D.M. also thanks the Department of Science and Technology, India, for the financial support through the Extra Mural Research funding (EMR/2016/006500).He, J.; Dhakshinamoorthy, A.; Primo Arnau, AM.; García Gómez, H. (2017). Iron Nanoparticles Embedded in Graphitic Carbon Matrix as Heterogeneous Catalysts for the Oxidative C-N Coupling of Aromatic N-H Compounds and Amides. ChemCatChem. 9(15):3003-3012. https://doi.org/10.1002/cctc.201700429S30033012915Astruc, D., Lu, F., & Aranzaes, J. R. (2005). Nanoparticles as Recyclable Catalysts: The Frontier between Homogeneous and Heterogeneous Catalysis. Angewandte Chemie International Edition, 44(48), 7852-7872. doi:10.1002/anie.200500766Astruc, D., Lu, F., & Aranzaes, J. R. (2005). Nanopartikel als regenerierbare Katalysatoren: an der Nahtstelle zwischen homogener und heterogener Katalyse. Angewandte Chemie, 117(48), 8062-8083. doi:10.1002/ange.200500766Haruta, M. (2002). CATTECH, 6(3), 102-115. doi:10.1023/a:1020181423055Narayanan, R., & El-Sayed, M. A. (2005). Catalysis with Transition Metal Nanoparticles in Colloidal Solution:  Nanoparticle Shape Dependence and Stability. The Journal of Physical Chemistry B, 109(26), 12663-12676. doi:10.1021/jp051066pMikami, Y., Dhakshinamoorthy, A., Alvaro, M., & García, H. (2013). Catalytic activity of unsupported gold nanoparticles. Catal. Sci. Technol., 3(1), 58-69. doi:10.1039/c2cy20068fHaruta, M. (1997). Size- and support-dependency in the catalysis of gold. Catalysis Today, 36(1), 153-166. doi:10.1016/s0920-5861(96)00208-8Haruta, M. (2004). Gold as a novel catalyst in the 21st century: Preparation, working mechanism and applications. Gold Bulletin, 37(1-2), 27-36. doi:10.1007/bf03215514Chinchilla, R., & Nájera, C. (2011). Recent advances in Sonogashira reactions. Chemical Society Reviews, 40(10), 5084. doi:10.1039/c1cs15071eDhakshinamoorthy, A., Navalon, S., Alvaro, M., & Garcia, H. (2012). Metal Nanoparticles as Heterogeneous Fenton Catalysts. ChemSusChem, 5(1), 46-64. doi:10.1002/cssc.201100517Farina, V. (2004). High-Turnover Palladium Catalysts in Cross-Coupling and Heck Chemistry: A Critical Overview. 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Synthesis of Nickel Nanoparticles with N-Doped Graphene Shells for Catalytic Reduction Reactions. ChemCatChem, 8(1), 129-134. doi:10.1002/cctc.201500848Westerhaus, F. A., Jagadeesh, R. V., Wienhöfer, G., Pohl, M.-M., Radnik, J., Surkus, A.-E., … Beller, M. (2013). Heterogenized cobalt oxide catalysts for nitroarene reduction by pyrolysis of molecularly defined complexes. Nature Chemistry, 5(6), 537-543. doi:10.1038/nchem.1645Banerjee, A., Gokhale, R., Bhatnagar, S., Jog, J., Bhardwaj, M., Lefez, B., … Ogale, S. (2012). MOF derived porous carbon–Fe3O4 nanocomposite as a high performance, recyclable environmental superadsorbent. Journal of Materials Chemistry, 22(37), 19694. doi:10.1039/c2jm33798cHu, J., Wang, H., Gao, Q., & Guo, H. (2010). Porous carbons prepared by using metal–organic framework as the precursor for supercapacitors. Carbon, 48(12), 3599-3606. doi:10.1016/j.carbon.2010.06.008Farad. Discuss 2016 https://doi.org/10.1039/C6FD00198JWezendonk, T. A., Santos, V. P., Nasalevich, M. A., Warringa, Q. S. E., Dugulan, A. I., Chojecki, A., … Gascon, J. (2016). Elucidating the Nature of Fe Species during Pyrolysis of the Fe-BTC MOF into Highly Active and Stable Fischer–Tropsch Catalysts. ACS Catalysis, 6(5), 3236-3247. doi:10.1021/acscatal.6b00426An, B., Cheng, K., Wang, C., Wang, Y., & Lin, W. (2016). Pyrolysis of Metal–Organic Frameworks to Fe3O4@Fe5C2 Core–Shell Nanoparticles for Fischer–Tropsch Synthesis. ACS Catalysis, 6(6), 3610-3618. doi:10.1021/acscatal.6b00464Santos, V. P., Wezendonk, T. A., Jaén, J. J. D., Dugulan, A. I., Nasalevich, M. A., Islam, H.-U., … Gascon, J. (2015). Metal organic framework-mediated synthesis of highly active and stable Fischer-Tropsch catalysts. Nature Communications, 6(1). doi:10.1038/ncomms7451DE JONG, K. P., & GEUS, J. W. (2000). Carbon Nanofibers: Catalytic Synthesis and Applications. Catalysis Reviews, 42(4), 481-510. doi:10.1081/cr-100101954Joo, S. H., Choi, S. J., Oh, I., Kwak, J., Liu, Z., Terasaki, O., & Ryoo, R. (2001). Ordered nanoporous arrays of carbon supporting high dispersions of platinum nanoparticles. Nature, 412(6843), 169-172. doi:10.1038/35084046Serp, P. (2003). Carbon nanotubes and nanofibers in catalysis. Applied Catalysis A: General, 253(2), 337-358. doi:10.1016/s0926-860x(03)00549-0Chen, Z., Higgins, D., Yu, A., Zhang, L., & Zhang, J. (2011). A review on non-precious metal electrocatalysts for PEM fuel cells. Energy & Environmental Science, 4(9), 3167. doi:10.1039/c0ee00558dSherry, B. D., & Fürstner, A. (2008). The Promise and Challenge of Iron-Catalyzed Cross Coupling. Accounts of Chemical Research, 41(11), 1500-1511. doi:10.1021/ar800039xThomé, I., Nijs, A., & Bolm, C. (2012). Trace metal impurities in catalysis. Chemical Society Reviews, 41(3), 979. doi:10.1039/c2cs15249eSaidulu, G., Kumar, R. A., & Reddy, K. R. (2015). Iron-catalyzed C–N bond formation via oxidative Csp3–H bond functionalization adjacent to nitrogen in amides and anilines: Synthesis of N-alkyl and N-benzyl azoles. Tetrahedron Letters, 56(28), 4200-4203. doi:10.1016/j.tetlet.2015.05.048Xia, Q., & Chen, W. (2012). Iron-Catalyzed N-Alkylation of Azoles via Cleavage of an sp3 C–H Bond Adjacent to a Nitrogen Atom. The Journal of Organic Chemistry, 77(20), 9366-9373. doi:10.1021/jo301568eTruong, T., Nguyen, K. D., Doan, S. H., & Phan, N. T. S. (2016). Efficient and recyclable Cu2(BPDC)2(DABCO)-catalyzed direct amination of activated sp3 C H bonds by N–H heterocycles. Applied Catalysis A: General, 510, 27-33. doi:10.1016/j.apcata.2015.10.042Chen, F., Topf, C., Radnik, J., Kreyenschulte, C., Lund, H., Schneider, M., … Beller, M. (2016). Stable and Inert Cobalt Catalysts for Highly Selective and Practical Hydrogenation of C≡N and C═O Bonds. Journal of the American Chemical Society, 138(28), 8781-8788. doi:10.1021/jacs.6b03439Cui, X., Li, Y., Bachmann, S., Scalone, M., Surkus, A.-E., Junge, K., … Beller, M. (2015). Correction to «Synthesis and Characterization of Iron–Nitrogen-Doped Graphene/Core–Shell Catalysts: Efficient Oxidative Dehydrogenation of N-Heterocycles». Journal of the American Chemical Society, 138(1), 457-457. doi:10.1021/jacs.5b10746He, L., Weniger, F., Neumann, H., & Beller, M. (2016). Synthesis, Characterization, and Application of Metal Nanoparticles Supported on Nitrogen-Doped Carbon: Catalysis beyond Electrochemistry. Angewandte Chemie International Edition, 55(41), 12582-12594. doi:10.1002/anie.201603198He, L., Weniger, F., Neumann, H., & Beller, M. (2016). Synthese, Charakterisierung und Anwendungen von Metall-Nanopartikeln nach Fixierung auf N-dotiertem Kohlenstoff: Katalyse jenseits der Elektrochemie. Angewandte Chemie, 128(41), 12770-12783. doi:10.1002/ange.201603198Ziccarelli, I., Neumann, H., Kreyenschulte, C., Gabriele, B., & Beller, M. (2016). Pd-Supported on N-doped carbon: improved heterogeneous catalyst for base-free alkoxycarbonylation of aryl iodides. Chemical Communications, 52(86), 12729-12732. doi:10.1039/c6cc07269kPrimo, A., Atienzar, P., Sanchez, E., Delgado, J. M., & García, H. (2012). From biomass wastes to large-area, high-quality, N-doped graphene: catalyst-free carbonization of chitosan coatings on arbitrary substrates. Chemical Communications, 48(74), 9254. doi:10.1039/c2cc34978gPrimo, A., Sánchez, E., Delgado, J. M., & García, H. (2014). High-yield production of N-doped graphitic platelets by aqueous exfoliation of pyrolyzed chitosan. Carbon, 68, 777-783. doi:10.1016/j.carbon.2013.11.068Abellán, G., Latorre-Sánchez, M., Fornés, V., Ribera, A., & García, H. (2012). Graphene as a carbon source effects the nanometallurgy of nickel in Ni,Mn layered double hydroxide–graphene oxide composites. Chemical Communications, 48(93), 11416. doi:10.1039/c2cc35750jLatorre-Sanchez, M., Atienzar, P., Abellán, G., Puche, M., Fornés, V., Ribera, A., & García, H. (2012). The synthesis of a hybrid graphene–nickel/manganese mixed oxide and its performance in lithium-ion batteries. Carbon, 50(2), 518-525. doi:10.1016/j.carbon.2011.09.007Park, E., Ostrovski, O., Zhang, J., Thomson, S., & Howe, R. (2001). Characterization of phases formed in the iron carbide process by X-ray diffraction, mossbauer, X-ray photoelectron spectroscopy, and raman spectroscopy analyses. Metallurgical and Materials Transactions B, 32(5), 839-845. doi:10.1007/s11663-001-0071-1Peng, S., Wang, C., Xie, J., & Sun, S. (2006). Synthesis and Stabilization of Monodisperse Fe Nanoparticles. Journal of the American Chemical Society, 128(33), 10676-10677. doi:10.1021/ja063969hPrimo, A., Esteve-Adell, I., Blandez, J. F., Dhakshinamoorthy, A., Álvaro, M., Candu, N., … García, H. (2015). High catalytic activity of oriented 2.0.0 copper(I) oxide grown on graphene film. Nature Communications, 6(1). doi:10.1038/ncomms9561Primo, A., Esteve-Adell, I., Coman, S. N., Candu, N., Parvulescu, V. I., & Garcia, H. (2015). One-Step Pyrolysis Preparation of 1.1.1 Oriented Gold Nanoplatelets Supported on Graphene and Six Orders of Magnitude Enhancement of the Resulting Catalytic Activity. Angewandte Chemie International Edition, 55(2), 607-612. doi:10.1002/anie.201508908Primo, A., Esteve-Adell, I., Coman, S. N., Candu, N., Parvulescu, V. I., & Garcia, H. (2015). One-Step Pyrolysis Preparation of 1.1.1 Oriented Gold Nanoplatelets Supported on Graphene and Six Orders of Magnitude Enhancement of the Resulting Catalytic Activity. Angewandte Chemie, 128(2), 617-622. doi:10.1002/ange.201508908Mateo, D., Esteve-Adell, I., Albero, J., Royo, J. F. S., Primo, A., & Garcia, H. (2016). 111 oriented gold nanoplatelets on multilayer graphene as visible light photocatalyst for overall water splitting. Nature Communications, 7(1). doi:10.1038/ncomms11819Buaki-Sogo, M., Serra, M., Primo, A., Alvaro, M., & Garcia, H. (2012). Alginate as Template in the Preparation of Active Titania Photocatalysts. ChemCatChem, 5(2), 513-518. doi:10.1002/cctc.201200386Lavorato, C., Primo, A., Molinari, R., & García, H. (2014). Natural Alginate as a Graphene Precursor and Template in the Synthesis of Nanoparticulate Ceria/Graphene Water Oxidation Photocatalysts. ACS Catalysis, 4(2), 497-504. doi:10.1021/cs401068mBuchwald, S. L., & Bolm, C. (2009). On the Role of Metal Contaminants in Catalyses with FeCl3. Angewandte Chemie International Edition, 48(31), 5586-5587. doi:10.1002/anie.200902237Buchwald, S. L., & Bolm, C. (2009). On the Role of Metal Contaminants in Catalyses with FeCl3. Angewandte Chemie, 121(31), 5694-5695. doi:10.1002/ange.20090223

In-flame soot quantification of diesel sprays under sooting/non-sooting critical conditions in an optical engine

[EN] Because of the challenge of meeting stringent emissions regulations for internal combustion engines, some advanced low temperature combustion modes have been raised in recent decades to improve combustion efficiency. Therefore, detailed understanding and capability for accurate prediction of in-flame soot processes under such low sooting conditions are becoming necessary. Nowadays, a lot of investigations have been carried out to quantify in-flame soot in Diesel sprays under high sooting conditions by means of different optical techniques. However, no information of soot quantification can be found for sooting/non-sooting critical conditions. In current study, the instantaneous soot production in a two-stroke optical engine under low sooting conditions has been measured by means of a Diffused back-illumination extinction technique (DBI) and two-color method (2C) simultaneously. The fuels used were n-dodecane and n-heptane, which have been injected separately though two different injectors equipped with single-hole nozzles. A large cycle-to-cycle variation on soot production can be observed under such operating conditions, however the in-cylinder heat release traces were quite repeatable. It is the same with the well-known trends of soot amount to operating conditions that the probability of sooting cycles increases with higher ambient temperature, higher ambient density and lower injection pressure. Both techniques present a pretty good agreement on soot amount when the peak of KL value is close to 1. However, the KL value of two-color method becomes bigger than that of DBI and the difference increases with lower sooting conditions.This study was partially funded by the Natural Science Foundation of China (No. 51876083), China Postdoctoral Science Foundation (2018M642176) and High-tech Research Key laboratory of Zhenjiang (SS2018002)Xuan, T.; Pastor, JV.; García-Oliver, JM.; García Martínez, A.; He, Z.; Wang, Q.; Reyes, M. (2019). In-flame soot quantification of diesel sprays under sooting/non-sooting critical conditions in an optical engine. Applied Thermal Engineering. 149:1-10. https://doi.org/10.1016/j.applthermaleng.2018.11.112S11014

Novel Sensors Based on the Symmetry Properties of Split Ring Resonators (SRRs)

The symmetry properties of split ring resonators (SRRs) are exploited for the implementation of novel sensing devices. The proposed structure consists of a coplanar waveguide (CPW) loaded with movable SRRs on the back substrate side. It is shown that if the SRRs are placed with the slits aligned with the symmetry plane of the CPW, the structure is transparent to signal propagation. However, if the symmetry is broken, a net axial magnetic field can be induced in the inner region of the SRRs, and signal propagation is inhibited at resonance. The proposed structures can be useful as alignment sensors, position sensors and angle sensors. This novel sensing principle is validated through experiment

One-Step Preparation of Large Area Films of Oriented MoS2 Nanoparticles on Multilayer Graphene and Its Electrocatalytic Activity for Hydrogen Evolution

[EN] MoS2 is a promising material to replace Pt-based catalysts for the hydrogen evolution reaction (HER), due to its excellent stability and high activity. In this work, MoS2 nanoparticles supported on graphitic carbon (about 20 nm) with a preferential 002 facet orientation have been prepared by pyrolysis of alginic acid films on quartz containing adsorbed (NH4)(2)MoS4 at 900 degrees C under Ar atmosphere. Although some variation of the electrocatalytic activity has been observed from batch to batch, the MoS2 sample exhibited activity for HER (a potential onset between 0.2 and 0.3 V vs. SCE), depending on the concentrations of (NH4)(2)MoS4 precursor used in the preparation process. The loading and particle size of MoS2, which correlate with the amount of exposed active sites in the sample, are the main factors influencing the electrocatalytic activity.Financial support by the Spanish Ministry of Economy and Competitiveness (Severo Ochoa and CTQ2015-69513-CO2-R1) and Generalidad Valenciana (Prometeo 2013/014) is gratefully acknowledged. Jinbao He thanks the Chinese Scholarship Council for supporting his PhD studies.He, J.; Fernández-Blanco, AC.; Primo Arnau, AM.; García Gómez, H. (2018). One-Step Preparation of Large Area Films of Oriented MoS2 Nanoparticles on Multilayer Graphene and Its Electrocatalytic Activity for Hydrogen Evolution. Materials. 11(1):1-11. https://doi.org/10.3390/ma11010168S111111Chhowalla, M., Shin, H. S., Eda, G., Li, L.-J., Loh, K. P., & Zhang, H. (2013). The chemistry of two-dimensional layered transition metal dichalcogenide nanosheets. Nature Chemistry, 5(4), 263-275. doi:10.1038/nchem.1589Lukowski, M. A., Daniel, A. S., Meng, F., Forticaux, A., Li, L., & Jin, S. (2013). Enhanced Hydrogen Evolution Catalysis from Chemically Exfoliated Metallic MoS2 Nanosheets. Journal of the American Chemical Society, 135(28), 10274-10277. doi:10.1021/ja404523sVoiry, D., Yamaguchi, H., Li, J., Silva, R., Alves, D. C. B., Fujita, T., … Chhowalla, M. (2013). Enhanced catalytic activity in strained chemically exfoliated WS2 nanosheets for hydrogen evolution. Nature Materials, 12(9), 850-855. doi:10.1038/nmat3700Li, Y., Wang, H., Xie, L., Liang, Y., Hong, G., & Dai, H. (2011). MoS2Nanoparticles Grown on Graphene: An Advanced Catalyst for the Hydrogen Evolution Reaction. Journal of the American Chemical Society, 133(19), 7296-7299. doi:10.1021/ja201269bLatorre-Sánchez, M., Esteve-Adell, I., Primo, A., & García, H. (2015). Innovative preparation of MoS2–graphene heterostructures based on alginate containing (NH4)2MoS4 and their photocatalytic activity for H2 generation. Carbon, 81, 587-596. doi:10.1016/j.carbon.2014.09.093Primo, A., Sánchez, E., Delgado, J. M., & García, H. (2014). High-yield production of N-doped graphitic platelets by aqueous exfoliation of pyrolyzed chitosan. Carbon, 68, 777-783. doi:10.1016/j.carbon.2013.11.068Mateo, D., Esteve-Adell, I., Albero, J., Royo, J. F. S., Primo, A., & Garcia, H. (2016). 111 oriented gold nanoplatelets on multilayer graphene as visible light photocatalyst for overall water splitting. Nature Communications, 7(1). doi:10.1038/ncomms11819Primo, A., Esteve-Adell, I., Blandez, J. F., Dhakshinamoorthy, A., Álvaro, M., Candu, N., … García, H. (2015). High catalytic activity of oriented 2.0.0 copper(I) oxide grown on graphene film. Nature Communications, 6(1). doi:10.1038/ncomms9561Primo, A., Esteve-Adell, I., Coman, S. N., Candu, N., Parvulescu, V. I., & Garcia, H. (2015). One-Step Pyrolysis Preparation of 1.1.1 Oriented Gold Nanoplatelets Supported on Graphene and Six Orders of Magnitude Enhancement of the Resulting Catalytic Activity. Angewandte Chemie International Edition, 55(2), 607-612. doi:10.1002/anie.201508908Primo, A., Atienzar, P., Sanchez, E., Delgado, J. M., & García, H. (2012). From biomass wastes to large-area, high-quality, N-doped graphene: catalyst-free carbonization of chitosan coatings on arbitrary substrates. Chemical Communications, 48(74), 9254. doi:10.1039/c2cc34978gPedraza, F., Cruz-Reyes, J., Acosta, D., Yanez, M. J., Avalos-Borja, M., & Fuentes, S. (1993). Journal of Physics: Condensed Matter, 5(33A), A219-A220. doi:10.1088/0953-8984/5/33a/069Li, H., Zhang, Q., Yap, C. C. R., Tay, B. K., Edwin, T. H. T., Olivier, A., & Baillargeat, D. (2012). From Bulk to Monolayer MoS2: Evolution of Raman Scattering. Advanced Functional Materials, 22(7), 1385-1390. doi:10.1002/adfm.201102111Yan, Y., Ge, X., Liu, Z., Wang, J.-Y., Lee, J.-M., & Wang, X. (2013). Facile synthesis of low crystalline MoS2 nanosheet-coated CNTs for enhanced hydrogen evolution reaction. Nanoscale, 5(17), 7768. doi:10.1039/c3nr02994hLi, H., Tsai, C., Koh, A. L., Cai, L., Contryman, A. W., Fragapane, A. H., … Zheng, X. (2015). Activating and optimizing MoS2 basal planes for hydrogen evolution through the formation of strained sulphur vacancies. Nature Materials, 15(1), 48-53. doi:10.1038/nmat4465Tsai, C., Chan, K., Nørskov, J. K., & Abild-Pedersen, F. (2015). Theoretical insights into the hydrogen evolution activity of layered transition metal dichalcogenides. Surface Science, 640, 133-140. doi:10.1016/j.susc.2015.01.01

The adaptors Grb10 and Grb14 are calmodulin-binding proteins

We identified the Grb7 family members, Grb10 and Grb14, as Ca2+-dependent CaM-binding proteins using Ca2+-dependent CaM-affinity chromatography as we previously did with Grb7. The potential CaM-binding sites were identified and experimentally tested using fluorescent-labeled peptides corresponding to these sites. The apparent affinity constant of these peptides for CaM, and the minimum number of calcium ions bound to CaM that are required for effective binding to these peptides were also determined. We prepared deletion mutants of the three adaptor proteins lacking the identified sites and determined that they lost or strongly diminished their CaM-binding capacity following the sequence Grb7 > > Grb14 > Grb10. More than one CaM-binding site and/or accessory CaM-binding sites appear to exist in Grb10 and Grb14, as compared to a single one present in Grb7.Secretaría de Estado de Investigación, Desarrollo e Innovación SAF2011-23494, SAF2014-52048-