Journal articles: 'Nucleation. Catalysis'

1

Hoffmeyer, M. K., and J. H. Perepezko. "Nucleation catalysis by dispersed particles." Scripta Metallurgica 22, no. 7 (January 1988): 1143–48. http://dx.doi.org/10.1016/s0036-9748(88)80120-0.

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de Cicco, Michael P., and John H. Perepezko. "Catalytic Effect of Nanoparticles on Primary and Secondary Phase Nucleation." Materials Science Forum 765 (July 2013): 250–54. http://dx.doi.org/10.4028/www.scientific.net/msf.765.250.

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Nanoparticles were shown to catalyze nucleation of primary and secondary phases in metal matrix nanocomposites (MMNCs). This catalysis is important as it contributes to the mechanical property enhancement in the MMNCs. Primary aluminium grain refinement was demonstrated in A356 matrix nanocomposites. Various types and sizes of nanoparticles (SiC, TiC, γ-Al2O3; 10-96 nm) were used to make these MMNCs and in all cases the MMNCs had smaller, more equiaxed grains compared to the reference A356. Using the droplet emulsion technique, undercoolings were shown to be significantly reduced. Undercoolings in the MMNCs were in good general agreement with the undercooling necessary for free growth, suggesting the applicability of this model to nucleation on nanoscale catalysts. Secondary phase nucleation catalysis was demonstrated in a zinc alloy AC43A MMNC and a binary Mg-4Zn MMNC. In AC43A, secondary phase nucleation was catalyzed with the addition of various nanoparticles (TiC, SiC, γ-Al2O3). The secondary phase nucleation catalysis in AC43A coincided with ductility enhancement. In Mg-4Zn, SiC nanoparticle addition changed the secondary phases that formed. MgZn2 was formed in the MMNC at relatively high temperatures consuming the Zn and reducing the amount of the low temperature Mg2Zn3 phase that formed in the reference alloy. The change in secondary phase formation coincided with significant enhancement in strength and ductility.

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von Windheim, Jesko A., and Jeffrey T. Glass. "Improved uniformity and selected area deposition of diamond by the oxy-acetylene flame method." Journal of Materials Research 7, no. 8 (August 1992): 2144–50. http://dx.doi.org/10.1557/jmr.1992.2144.

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The role of SiO2 in nucleation of diamond has been investigated in an oxy-acetylene flame. It was found that growth methods that minimize SiO2 formation enhance diamond nucleation. A short pretreatment of a scratched Si surface in a low oxygen-to-acetylene ratio flame, at a distance 1.5 cm from the flame core, significantly improved uniformity of subsequent diamond growth. When scratched surfaces were intentionally oxidized, nucleation of diamond was completely inhibited. By using a mask to controllably deposit SiO2 on a scratched Si surface, highly selective deposition of diamond was achieved with resolution below 5 μm. These results are discussed with reference to competing oxidation and carbon formation processes that take place during the nucleation of diamond. During the nucleation stage, carbon may be deposited on the scratched Si via a route in which the Si surface catalyzes carbon formation reactions that are otherwise kinetically unfavorable. The formation of an oxide layer, on the other hand, would act to passivate the surface, and thus inhibit carbon formation via a catalytic route. The decomposition of CO to C and CO2 is given as an example of a reaction that is favored at temperatures below 1000 K, but requires surface catalysis to proceed because it remains frozen out in the gas phase due to a very slow reaction rate.

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Perepezko, J. H., and W. S. Tong. "Nucleation–catalysis–kinetics analysis under dynamic conditions." Philosophical Transactions of the Royal Society of London. Series A: Mathematical, Physical and Engineering Sciences 361, no. 1804 (January 27, 2003): 447–61. http://dx.doi.org/10.1098/rsta.2002.1151.

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Li, Xin Yu. "Mechanisms of 1D Crystal Growth in Chemical Vapor Deposition: ZnO Nanowires." Advanced Materials Research 463-464 (February 2012): 1463–67. http://dx.doi.org/10.4028/www.scientific.net/amr.463-464.1463.

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Abstract. ZnO nanowires synthesis throught oxidative evaporation of pure zinc powder without catalyst is studied in detail to understand the nucleation and growth mechanisms involved with the so-called “self-catalysis” schemes. The structural features associated with different growth stages were monitored using scanning electron microscopy (SEM), describe the direct observation of the nucleation and growth process. X-ray diffraction (XRD) and energy-dispersive X-ray spectroscopy (EDS) demonstrate that the as-obtained sample can be indexed to high crystallinity with wurtzite structure and only contain Zn and O without the presence of any impurities.

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6

Todorova, S., J. W. P. Schmelzer, and I. Gutzow. "Nucleation Catalysis in Metastable Liquids: Inborn Active Sites." Crystal Research and Technology 35, no. 5 (May 2000): 515–27. http://dx.doi.org/10.1002/1521-4079(200005)35:5<515::aid-crat515>3.0.co;2-9.

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7

Liang, Wei, Hao Yan, Chen Chen, Dong Lin, Kexin Tan, Xiang Feng, Yibin Liu, Xiaobo Chen, Chaohe Yang, and Honghong Shan. "Revealing the Effect of Nickel Particle Size on Carbon Formation Type in the Methane Decomposition Reaction." Catalysts 10, no. 8 (August 6, 2020): 890. http://dx.doi.org/10.3390/catal10080890.

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Carbon species deposition is recognized as the primary cause of catalyst deactivation for hydrocarbon cracking and reforming reactions. Exploring the formation mechanism and influencing factors for carbon deposits is crucial for the design of rational catalysts. In this work, a series of NixMgyAl-800 catalysts with nickel particles of varying mean sizes between 13.2 and 25.4 nm were obtained by co-precipitation method. These catalysts showed different deactivation behaviors in the catalytic decomposition of methane (CDM) reaction and the deactivation rate of catalysts increased with the decrease in nickel particle size. Employing TG-MS and TEM characterizations, we found that carbon nanotubes which could keep catalyst activity were more prone to form on large nickel particles, while encapsulated carbon species that led to deactivation were inclined to deposit on small particles. Supported by DFT calculations, we proposed the insufficient supply of carbon atoms and rapid nucleation of carbon precursors caused by the lesser terrace/step ratio on smaller nickel particles, compared with large particles, inhibit the formation of carbon nanotube, leading to the formation of encapsulated carbon species. The findings in this work may provide guidance for the rational design of nickel-based catalysts for CDM and other methane conversion reactions.

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8

Chatterjee, Dipanwita, Akash R, K. Kamalnath, Rafia Ahmad, Abhishek Kumar Singh, and N. Ravishankar. "Orientation Selection during Heterogeneous Nucleation: Implications for Heterogeneous Catalysis." Journal of Physical Chemistry C 121, no. 18 (April 27, 2017): 10027–37. http://dx.doi.org/10.1021/acs.jpcc.7b02237.

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9

De Cicco, Michael P., Lih-Sheng Turng, Xiaochun Li, and John H. Perepezko. "Nucleation Catalysis in Aluminum Alloy A356 Using Nanoscale Inoculants." Metallurgical and Materials Transactions A 42, no. 8 (January 29, 2011): 2323–30. http://dx.doi.org/10.1007/s11661-011-0607-1.

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10

Dokter, Wim H., Harold F. van Garderen, Theo P. M. Beelen, Rutger A. van Santen, and Wim Bras. "Homogeneous versus Heterogeneous Zeolite Nucleation." Angewandte Chemie International Edition in English 34, no. 1 (January 16, 1995): 73–75. http://dx.doi.org/10.1002/anie.199500731.

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11

Wirges, Christian T, Jan Timper, Monika Fischler, Alla S Sologubenko, Joachim Mayer, Ulrich Simon, and Thomas Carell. "Controlled Nucleation of DNA Metallization." Angewandte Chemie International Edition 48, no. 1 (November 28, 2008): 219–23. http://dx.doi.org/10.1002/anie.200803123.

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12

Thacker, Dev, Kalyani Sanagavarapu, Birgitta Frohm, Georg Meisl, Tuomas P. J. Knowles, and Sara Linse. "The role of fibril structure and surface hydrophobicity in secondary nucleation of amyloid fibrils." Proceedings of the National Academy of Sciences 117, no. 41 (October 1, 2020): 25272–83. http://dx.doi.org/10.1073/pnas.2002956117.

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Crystals, nanoparticles, and fibrils catalyze the generation of new aggregates on their surface from the same type of monomeric building blocks as the parent assemblies. This secondary nucleation process can be many orders of magnitude faster than primary nucleation. In the case of amyloid fibrils associated with Alzheimer’s disease, this process leads to the multiplication and propagation of aggregates, whereby short-lived oligomeric intermediates cause neurotoxicity. Understanding the catalytic activity is a fundamental goal in elucidating the molecular mechanisms of Alzheimer’s and associated diseases. Here we explore the role of fibril structure and hydrophobicity by asking whether the V18, A21, V40, and A42 side chains which are exposed on the Aβ42 fibril surface as continuous hydrophobic patches play a role in secondary nucleation. Single, double, and quadruple serine substitutions were made. Kinetic analyses of aggregation data at multiple monomer concentrations reveal that all seven mutants retain the dominance of secondary nucleation as the main mechanism of fibril proliferation. This finding highlights the generality of secondary nucleation and its independence of the detailed molecular structure. Cryo-electron micrographs reveal that the V18S substitution causes fibrils to adopt a distinct morphology with longer twist distance than variants lacking this substitution. Self- and cross-seeding data show that surface catalysis is only efficient between peptides of identical morphology, indicating a templating role of secondary nucleation with structural conversion at the fibril surface. Our findings thus provide clear evidence that the propagation of amyloid fibril strains is possible even in systems dominated by secondary nucleation rather than fragmentation.

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13

Byun, Mi Yeon, Dae-Won Park, and Man Sig Lee. "Effect of Oxide Supports on the Activity of Pd Based Catalysts for Furfural Hydrogenation." Catalysts 10, no. 8 (July 24, 2020): 837. http://dx.doi.org/10.3390/catal10080837.

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We investigated the effect of oxide supports on the hydrogenation of furfural over Pd catalysts on various supports (Al2O3, SiO2, TiO2, CeO2, and ZrO2). Pd catalysts (5 wt%) prepared by chemical reduction on various supports. The dispersion and uniformity of Pd were affected by the properties of the support and by the nucleation and growth of Pd. The conversion of furfural was enhanced by greater Pd dispersion. The selectivity for cyclopentanone and tetrahydrofurfuryl alcohol was affected by physicochemical properties of Pd catalyst and reaction parameters. High Pd dispersion and high acidity of the catalyst led to greater C=C hydrogenation, thereby, generating more tetrahydrofurfuryl alcohol. The Pd/TiO2 catalyst showed the highest cyclopentanone yield than other catalysts. The Pd/TiO2 catalyst exhibited the >99% furfural conversion, 55.6% cyclopentanone selectivity, and 55.5% cyclopentanone yield under the optimal conditions; 20 bar of H2, at 170 °C for 4 h with 0.1 g of catalyst.

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14

De Cicco, Michael, Lih Sheng Turng, Xiao Chun Li, and John H. Perepezko. "Production of Semi-Solid Slurry through Heterogeneous Nucleation in Metal Matrix Nanocomposites (MMNC) Using Nano-Scale Ultrasonically Dispersed Inoculants." Solid State Phenomena 141-143 (July 2008): 487–92. http://dx.doi.org/10.4028/www.scientific.net/ssp.141-143.487.

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Ever since copious nucleation was shown to be an efficient, cost effective method for producing semi-solid slurry, many processes have been developed to take advantage of the cost savings inherent in this method of slurry production. Despite great advances in various aspects of semi-solid processing, the cost competitive nature of the industry, most noticeably the auto industry, has prevented a wider adoption of semi-solid casting technology. This research aims to realize a more industrial appealing process by combining the synergistic benefits of semi-solid casting technology with metal matrix nanocomposite (MMNC) technology, thus creating higher value products with superior properties cost-effectively. To do this, a process that produces a semi-solid slurry though the nucleation catalysis induced by nanoparticle additions as small as 1 wt. % to alloys is proposed and the results are presented in this paper. Examination of the potential for nano-scale inoculants to catalyze nucleation of solidification showed that despite their small sizes, inoculants on the scale of tens of nanometers are capable of catalyzing nucleation in the zinc and aluminum alloys studied. Employing the differential scanning calorimetry (DSC), differential thermal analysis (DTA), and droplet emulsion techniques with nanocomposite samples showed a significant reduction in undercooling owing to the homogeneous distribution of nanoparticles by ultrasonic mixing and the potency of those nanoparticles to catalyze nucleation. Comparison of undercoolings between different types of nanoparticles, such as silicon carbide (SiC), gamma and alpha alumina (Al2O3), and titanium carbide (TiC), to relative potencies predicted by minimum lattice disregistry showed a strong correlation. Results were also examined in light of free growth and nucleation controlled grain initiation. For nanoparticles predicted to be potent nucleation catalysts by lattice disregistry, the undercoolings observed fell into the free growth controlled grain initiation regime.

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15

Zhang, Zhuolei, Ji Su, Ana Sanz Matias, Madeleine Gordon, Yi-Sheng Liu, Jinghua Guo, Chengyu Song, et al. "Enhanced and stabilized hydrogen production from methanol by ultrasmall Ni nanoclusters immobilized on defect-rich h-BN nanosheets." Proceedings of the National Academy of Sciences 117, no. 47 (November 9, 2020): 29442–52. http://dx.doi.org/10.1073/pnas.2015897117.

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Employing liquid organic hydrogen carriers (LOHCs) to transport hydrogen to where it can be utilized relies on methods of efficient chemical dehydrogenation to access this fuel. Therefore, developing effective strategies to optimize the catalytic performance of cheap transition metal-based catalysts in terms of activity and stability for dehydrogenation of LOHCs is a critical challenge. Here, we report the design and synthesis of ultrasmall nickel nanoclusters (∼1.5 nm) deposited on defect-rich boron nitride (BN) nanosheet (Ni/BN) catalysts with higher methanol dehydrogenation activity and selectivity, and greater stability than that of some other transition-metal based catalysts. The interface of the two-dimensional (2D) BN with the metal nanoparticles plays a strong role both in guiding the nucleation and growth of the catalytically active ultrasmall Ni nanoclusters, and further in stabilizing these nanoscale Ni catalysts against poisoning by interactions with the BN substrate. We provide detailed spectroscopy characterizations and density functional theory (DFT) calculations to reveal the origin of the high productivity, high selectivity, and high durability exhibited with the Ni/BN nanocatalyst and elucidate its correlation with nanocluster size and support–nanocluster interactions. This study provides insight into the role that the support material can have both regarding the size control of nanoclusters through immobilization during the nanocluster formation and also during the active catalytic process; this twofold set of insights is significant in advancing the understanding the bottom-up design of high-performance, durable catalytic systems for various catalysis needs.

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16

Draper, Neil D., Samuel F. Bakhoum, Allen E. Haddrell, and George R. Agnes. "Ion-Induced Nucleationin Solution: Promotion of Solute Nucleation in Charged Levitated Droplets." Journal of the American Chemical Society 129, no. 37 (September 2007): 11364–77. http://dx.doi.org/10.1021/ja067094i.

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17

Deng, Z. H., L. Li, W. Ding, K. Xiong, and Z. D. Wei. "Synthesized ultrathin MoS2 nanosheets perpendicular to graphene for catalysis of hydrogen evolution reaction." Chemical Communications 51, no. 10 (2015): 1893–96. http://dx.doi.org/10.1039/c4cc08491h.

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18

Anderson, I. E., J. Walleser, and J. L. Harringa. "Observations of nucleation catalysis effects during solidification of SnAgCuX solder joints." JOM 59, no. 7 (July 2007): 38–43. http://dx.doi.org/10.1007/s11837-007-0087-3.

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19

Reveles, J. Ulises, Patrizia Calaminici, Marcela R. Beltrán, Andres M. Köster, and Shiv N. Khanna. "H2O Nucleation around Au+." Journal of the American Chemical Society 129, no. 50 (December 2007): 15565–71. http://dx.doi.org/10.1021/ja074336l.

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20

Liang, Shuai, and Peter G. Kusalik. "The nucleation of gas hydrates near silica surfaces." Canadian Journal of Chemistry 93, no. 8 (August 2015): 791–98. http://dx.doi.org/10.1139/cjc-2014-0443.

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Understanding the nucleation and crystal growth of gas hydrates near mineral surfaces and in confinement are critical to the methane recovery from gas hydrate reservoirs. In this work, through molecular dynamics simulation studies, we present an exploration of the nucleation behavior of methane hydrates near model hydroxylated silica surfaces. Our simulation results indicate that the nucleation of methane hydrates can initiate from the silica surfaces despite of the structural mismatch of the two solid phases. A layer of intermediate half-cage structures was observed between the gas hydrate and silica surfaces, apparently helping to minimize the free energy penalty. These results have important implications to our understanding of the effects of solid surfaces on hydrate nucleation processes.

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21

Pelster, Stefan A, Rainer Kalamajka, Wolfgang Schrader, and Ferdi Schüth. "Monitoring the Nucleation of Zeolites by Mass Spectrometry." Angewandte Chemie International Edition 46, no. 13 (March 19, 2007): 2299–302. http://dx.doi.org/10.1002/anie.200604513.

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22

Wang, Ruiyao, Jun Yang, Zhiping Zheng, Michael D. Carducci, Jun Jiao, and Supapan Seraphin. "Dendron-Controlled Nucleation and Growth of Gold Nanoparticles." Angewandte Chemie International Edition 40, no. 3 (January 30, 2001): 549–52. http://dx.doi.org/10.1002/1521-3773(20010202)40:3<549::aid-anie549>3.0.co;2-p.

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23

Chen, Shuang, Hanmi Xi, and Lian Yu. "Cross-Nucleation between ROY Polymorphs." Journal of the American Chemical Society 127, no. 49 (December 2005): 17439–44. http://dx.doi.org/10.1021/ja056072d.

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24

Rimer, Jeffrey D., Aseem Chawla, and Thuy T. Le. "Crystal Engineering for Catalysis." Annual Review of Chemical and Biomolecular Engineering 9, no. 1 (June 7, 2018): 283–309. http://dx.doi.org/10.1146/annurev-chembioeng-060817-083953.

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Crystal engineering relies upon the ability to predictively control intermolecular interactions during the assembly of crystalline materials in a manner that leads to a desired (and predetermined) set of properties. Economics, scalability, and ease of design must be leveraged with techniques that manipulate the thermodynamics and kinetics of crystal nucleation and growth. It is often challenging to exact simultaneous control over multiple physicochemical properties, such as crystal size, habit, chirality, polymorph, and composition. Engineered materials often rely upon postsynthesis (top-down) processes to introduce properties that would otherwise be challenging to attain through direct (bottom-up) approaches. We discuss the application of crystal engineering to heterogeneous catalysts with a focus on four general themes: ( a) tailored nanocrystal size, ( b) controlled environments surrounding active sites, ( c) tuned morphology with well-defined facets, and ( d) hierarchical materials with disparate pore size and active site distributions. We focus on nonporous materials, including metals and metal oxides, and two classes of porous materials: zeolites and metal organic frameworks. We review novel synthesis methods involving synergistic experimental and computational design approaches, the challenges facing catalyst development, and opportunities for future advancement in crystal engineering.

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25

Elazab, Hany A., and Tamer T. El-Idreesy. "Polyvinylpyrrolidone - Reduced Graphene Oxide - Pd Nanoparticles as an Efficient Nanocomposite for Catalysis Applications in Cross-Coupling Reactions." Bulletin of Chemical Reaction Engineering & Catalysis 14, no. 3 (December 1, 2019): 490. http://dx.doi.org/10.9767/bcrec.14.3.3461.490-501.

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This paper reported a scientific approach adopting microwave-assisted synthesis as a synthetic route for preparing highly active palladium nanoparticles stabilized by polyvinylpyrrolidone (Pd/PVP) and supported on reduced Graphene oxide (rGO) as a highly active catalyst used for Suzuki, Heck, and Sonogashira cross coupling reactions with remarkable turnover number (6500) and turnover frequency of 78000 h-1. Pd/PVP nanoparticles supported on reduced Graphene oxide nanosheets (Pd-PVP/rGO) showed an outstanding performance through high catalytic activity towards cross coupling reactions. A simple, reproducible, and reliable method was used to prepare this efficient catalyst using microwave irradiation synthetic conditions. The synthesis approach requires simultaneous reduction of palladium and in the presence of Gaphene oxide (GO) nanosheets using ethylene glycol as a solvent and also as a strong reducing agent. The highly active and recyclable catalyst has so many advantages including the use of mild reaction conditions, short reaction times in an environmentally benign solvent system. Moreover, the prepared catalyst could be recycled for up to five times with nearly the same high catalytic activity. Furthermore, the high catalytic activity and recyclability of the prepared catalyst are due to the strong catalyst-support interaction. The defect sites in the reduced Graphene oxide (rGO) act as nucleation centers that enable anchoring of both Pd/PVP nanoparticles and hence, minimize the possibility of agglomeration which leads to a severe decrease in the catalytic activity. Copyright © 2019 BCREC Group. All rights reserved

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26

Sobczak, Szymon, Paulina Ratajczyk, and Andrzej Katrusiak. "High‐pressure Nucleation of Low‐Density Polymorphs**." Chemistry – A European Journal 27, no. 24 (March 4, 2021): 7069–73. http://dx.doi.org/10.1002/chem.202005121.

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27

Sobczak, Szymon, Paulina Ratajczyk, and Andrzej Katrusiak. "High‐pressure Nucleation of Low‐Density Polymorphs." Chemistry – A European Journal 27, no. 24 (April 15, 2021): 6999. http://dx.doi.org/10.1002/chem.202101159.

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28

Hanif, Farzana, Yingcen Liu, Jihong Liu, Caicheng Song, Liyan Zhang, Hua Lin, Rongwen Lu, and Shufen Zhang. "Ammonia-controlled synthesis of monodispersed N-doped carbon nanoparticles." New Journal of Chemistry 44, no. 36 (2020): 15403–9. http://dx.doi.org/10.1039/d0nj02924f.

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29

Liang, Yuan, Meili Sui, Maomao He, Zhiyong Wei, and Wanxi Zhang. "A Strategy of In Situ Catalysis and Nucleation of Biocompatible Zinc Salts of Amino Acids towards Poly(l-lactide) with Enhanced Crystallization Rate." Polymers 11, no. 5 (May 2, 2019): 790. http://dx.doi.org/10.3390/polym11050790.

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The intrinsic drawback of slow crystallization rate of poly(l-lactide) (PLLA) inevitably deteriorates its final properties of the molded articles. In this work, we proposed a new strategy towards poly(l-lactide) with enhanced crystallization rate by ring opening polymerization (ROP) of l-lactide (l-LA) catalyzed by biocompatible zinc salts of amino acids. For the first time we developed a one-pot facile method of zinc salts of amino acids acting dual roles of catalysis of l-LA polymerization and in situ nucleation of the as-prepared PLLA. Nine zinc salts of different amino acids, including three kinds of amino acids ligands (alanine, phenylalanine, and proline) with l/d-enantiomers and their equimolar racemic mixtures, were first prepared and tested as catalysts of l-LA polymerization. A partial racemization was observed for zinc salts of amino acids whereas no racemization was detected for the reference stannous octoate. The polymerization mechanism study showed that the interaction of zinc salts of amino acids and benzyl alcohol forms the actual initiator for l-LA polymerization. Isothermal crystallization kinetics analysis showed that the residual zinc salts of amino acids exhibited a significant nucleation effect on PLLA, evidenced by the promotion of the crystallization rate, depending on the amino acid ligand and its configuration. Meanwhile, the residual zinc salts of amino acids did not compromise the thermal stability of the pristine PLLA.

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30

Valdés, Carlos, Urs P. Spitz, Stefan W. Kubik, and Julius Rebek. "Pseudo-Spherical Host Molecules: Synthesis, Dimerization, and Nucleation Effects." Angewandte Chemie International Edition in English 34, no. 17 (September 15, 1995): 1885–87. http://dx.doi.org/10.1002/anie.199518851.

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31

Morin, Stephen A, Young-Hye La, Chi-Chun Liu, Jeremy A Streifer, Robert J Hamers, Paul F Nealey, and Song Jin. "Assembly of Nanocrystal Arrays by Block-Copolymer-Directed Nucleation." Angewandte Chemie International Edition 48, no. 12 (March 9, 2009): 2135–39. http://dx.doi.org/10.1002/anie.200805471.

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32

Wetz, Fabienne, Katerina Soulantica, Andrea Falqui, Marc Respaud, Etienne Snoeck, and Bruno Chaudret. "Hybrid Co–Au Nanorods: Controlling Au Nucleation and Location." Angewandte Chemie International Edition 46, no. 37 (September 17, 2007): 7079–81. http://dx.doi.org/10.1002/anie.200702017.

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Wiedenbeck, Eduard, Michael Kovermann, Denis Gebauer, and Helmut Cölfen. "Liquid Metastable Precursors of Ibuprofen as Aqueous Nucleation Intermediates." Angewandte Chemie International Edition 58, no. 52 (December 19, 2019): 19103–9. http://dx.doi.org/10.1002/anie.201910986.

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34

Ge, Lixia, Gan Yu, Xinqing Chen, Wenqian Li, Wenjie Xue, Minghuang Qiu, and Yuhan Sun. "Effects of particle size on bifunctional Pt/SAPO-11 catalysts in the hydroisomerization of n-dodecane." New Journal of Chemistry 44, no. 7 (2020): 2996–3003. http://dx.doi.org/10.1039/c9nj06215g.

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35

Sounart, Thomas L., Jun Liu, James A. Voigt, Mae Huo, Erik D. Spoerke, and Bonnie McKenzie. "Secondary Nucleation and Growth of ZnO." Journal of the American Chemical Society 129, no. 51 (December 2007): 15786–93. http://dx.doi.org/10.1021/ja071209g.

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36

Zhao, Dahui, and Jeffrey S. Moore. "Nucleation−Elongation Polymerization under Imbalanced Stoichiometry." Journal of the American Chemical Society 125, no. 52 (December 2003): 16294–99. http://dx.doi.org/10.1021/ja038252y.

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37

Lin, Chenfang, Gefen Corem, Oded Godsi, Gil Alexandrowicz, George R. Darling, and Andrew Hodgson. "Ice Nucleation on a Corrugated Surface." Journal of the American Chemical Society 140, no. 46 (October 29, 2018): 15804–11. http://dx.doi.org/10.1021/jacs.8b08796.

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38

Bunce, Samuel J., Yiming Wang, Katie L. Stewart, Alison E. Ashcroft, Sheena E. Radford, Carol K. Hall, and Andrew J. Wilson. "Molecular insights into the surface-catalyzed secondary nucleation of amyloid-β40 (Aβ40) by the peptide fragment Aβ16–22." Science Advances 5, no. 6 (June 2019): eaav8216. http://dx.doi.org/10.1126/sciadv.aav8216.

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Understanding the structural mechanism by which proteins and peptides aggregate is crucial, given the role of fibrillar aggregates in debilitating amyloid diseases and bioinspired materials. Yet, this is a major challenge as the assembly involves multiple heterogeneous and transient intermediates. Here, we analyze the co-aggregation of Aβ40 and Aβ16–22, two widely studied peptide fragments of Aβ42 implicated in Alzheimer’s disease. We demonstrate that Aβ16–22 increases the aggregation rate of Aβ40 through a surface-catalyzed secondary nucleation mechanism. Discontinuous molecular dynamics simulations allowed aggregation to be tracked from the initial random coil monomer to the catalysis of nucleation on the fibril surface. Together, the results provide insight into how dynamic interactions between Aβ40 monomers/oligomers on the surface of preformed Aβ16–22 fibrils nucleate Aβ40 amyloid assembly. This new understanding may facilitate development of surfaces designed to enhance or suppress secondary nucleation and hence to control the rates and products of fibril assembly.

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39

Metya, Atanu K., and Valeria Molinero. "Is Ice Nucleation by Organic Crystals Nonclassical? An Assessment of the Monolayer Hypothesis of Ice Nucleation." Journal of the American Chemical Society 143, no. 12 (March 17, 2021): 4607–24. http://dx.doi.org/10.1021/jacs.0c12012.

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40

Schwidetzky, Ralph, Max Lukas, Azade YazdanYar, Anna T. Kunert, Ulrich Pöschl, Katrin F. Domke, Janine Fröhlich‐Nowoisky, et al. "Specific Ion–Protein Interactions Influence Bacterial Ice Nucleation." Chemistry – A European Journal 27, no. 26 (March 16, 2021): 7402–7. http://dx.doi.org/10.1002/chem.202004630.

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41

Mora-Fonz, Miguel J., C. Richard A. Catlow, and Dewi W. Lewis. "Oligomerization and Cyclization Processes in the Nucleation of Microporous Silicas." Angewandte Chemie International Edition 44, no. 20 (May 13, 2005): 3082–86. http://dx.doi.org/10.1002/anie.200462524.

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42

Curland, Sofia, Elena Meirzadeh, Hagai Cohen, David Ehre, Joachim Maier, Meir Lahav, and Igor Lubomirsky. "The Contribution of Pyroelectricity of AgI Crystals to Ice Nucleation." Angewandte Chemie International Edition 57, no. 24 (May 15, 2018): 7076–79. http://dx.doi.org/10.1002/anie.201802291.

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Bohner, Bíborka, Tamás Bánsági, Ágota Tóth, Dezső Horváth, and Annette F. Taylor. "Periodic Nucleation of Calcium Phosphate in a Stirred Biocatalytic Reaction." Angewandte Chemie International Edition 59, no. 7 (February 10, 2020): 2823–28. http://dx.doi.org/10.1002/anie.201911213.

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44

Wallace, W. T., B. K. Min, and D. W. Goodman. "The nucleation, growth, and stability of oxide-supported metal clusters." Topics in Catalysis 34, no. 1-4 (May 2005): 17–30. http://dx.doi.org/10.1007/s11244-005-3786-4.

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45

Shen, Mingmin, Cynthia J. Jenks, J. W. Evans, and P. A. Thiel. "How Sulfur Controls Nucleation of Ag Islands on Ag(111)." Topics in Catalysis 54, no. 1-4 (January 27, 2011): 83–89. http://dx.doi.org/10.1007/s11244-011-9627-8.

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46

Belloni, J. "Nucleation, growth and properties of nanoclusters studied by radiation chemistry." Catalysis Today 113, no. 3-4 (April 2006): 141–56. http://dx.doi.org/10.1016/j.cattod.2005.11.082.

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47

Schwanke, Anderson Joel, Paloma Vinaches, Florian Meneau, Edisson Morgado, and Sibele Pergher. "Nucleation and crystallization of the MWW-type lamellar zeolitic precursor." Catalysis Today 344 (March 2020): 102–7. http://dx.doi.org/10.1016/j.cattod.2018.10.033.

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48

Daraboina, Nagu, Christine Malmos Perfeldt, and Nicolas von Solms. "Testing antifreeze protein from the longhorn beetle Rhagium mordax as a kinetic gas hydrate inhibitor using a high-pressure micro differential scanning calorimeter." Canadian Journal of Chemistry 93, no. 9 (September 2015): 1025–30. http://dx.doi.org/10.1139/cjc-2014-0543.

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Low dosage kinetic hydrate inhibitors are employed as alternatives to expensive thermodynamic inhibitors to manage the risk of hydrate formation inside oil and gas pipelines. These chemicals need to be tested at appropriate conditions in the laboratory before deployment in the field. A high pressure micro differential scanning calorimeter HP-μDSC VII (Setaram Inc.) containing two 50 cc high pressure cells (maximum operating pressure 40 MPa; temperature range –40 to 120 °C) was employed to observe methane hydrate formation and decomposition in the presence of hyperactive antifreeze protein from Rhagium mordax (RmAFP) and biodegradable synthetic kinetic inhibitor Luvicap Bio. A systematic capillary dispersion method was used, and this method enhanced the ability to detect the effect of various inhibitors on hydrate formation with small quantities. The presence of RmAFP and Luvicap Bio influence (inhibit) the hydrate formation phenomena significantly. Luvicap Bio (relative strength compared to buffer: 13.3 °C) is stronger than RmAFP (9.8 °C) as a nucleation inhibitor. However, the presence RmAFP not only delays hydrate nucleation but also reduces the amount of hydrate formed (20%–30%) after nucleation significantly. Unlike RmAFP, Luvicap Bio promoted the amount of hydrate formed after nucleation. The superior hydrate growth inhibition capability and predictable hydrate melting behavior compared to complex, heterogeneous hydrate melting with Luvicap Bio shows that RmAFP can be a potential natural green kinetic inhibitor for hydrate formation in pipelines.

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Stoporev, Andrey S., Andrey Yu Manakov, Lubov’ K. Altunina, Larisa A. Strelets, and Viktor I. Kosyakov. "Nucleation rates of methane hydrate from water in oil emulsions." Canadian Journal of Chemistry 93, no. 8 (August 2015): 882–87. http://dx.doi.org/10.1139/cjc-2014-0507.

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Nucleation of methane hydrate from water emulsions in five different kinds of crude oil and in decane have been studied with the use of isothermal methods. The experiments were conducted at a temperature of –5 °C and pressure of 12 MPa. It is shown that the nucleation rates tend to decrease with the increase in the density of the organic liquid used to make the emulsion. It is most likely that the observed regularities are related to the rate of methane diffusion to water surface.

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García, Juan-José, Raymundo Hernández-Esparza, Rubicelia Vargas, William Tiznado, and Jorge Garza. "Formation of small clusters of NaCl dihydrate in the gas phase." New Journal of Chemistry 43, no. 11 (2019): 4342–48. http://dx.doi.org/10.1039/c8nj06315j.

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Journal articles on the topic 'Nucleation. Catalysis'

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