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Instruments / Technical Area	Publication Details	Published
E01-JEM ARM 200CF	The direct synthesis of H2O2 using TS-1 supported catalysts Richard J. Lewis , Kenji Ueura , Yukimasa Fukuta , Simon J. Freakley , Liqun Kang , Feng Ryan Wang , Qian He , Jennifer. K. Edwards , David J. Morgan , Yasushi Yamamoto , Graham J. Hutchings Chemcatchem 6 DOI: 10.1002/cctc.201900100 Diamond Proposal Number(s): [19246] Show Abstract ▼ Abstract: In this study we show that using AuPd nanoparticles supported on a commercial titanium silicate (TS‐1) prepared using a wet co‐impregnation method it is possible to produce hydrogen peroxide from molecular H2 and O2 via the direct synthesis reaction. The effect of Au: Pd ratio and calcination temperature is evaluated as well as the role of Pt addition to the AuPd supported catalysts. The effect of Pt addition to AuPt nanoparticles is observed to result in a significant improvement in catalytic activity and selectivity to hydrogen peroxide with detailed characterisation indicating this is a result of selectively tuning the ratio of Pd oxidation states.	Mar 2019
B18-Core EXAFS E01-JEM ARM 200CF	Nanoporous carbon: Liquid-free synthesis and geometry dependent catalytic performance Ruoyu Xu , Liqun Kang , Johannes Knossalla , Jerrik Mielby , Qiming Wang , Bolun Wang , Junrun Feng , Guanjie He , Yudao Qin , Jijia Xie , Ann-christin Swertz , Qian He , Søren Kegnæs , Dan J.l. Brett , Ferdi Schüth , Feng Ryan Wang Acs Nano DOI: 10.1021/acsnano.8b09399 Diamond Proposal Number(s): [206191, 15151] Show Abstract ▼ Abstract: Nanostructured carbons with different pore geometries are prepared with a liquid-free nanocasting method. The method uses gases instead of liquid to disperse carbon precursor, leach templates and remove impurities, minimizing synthetic procedures and the use of chemicals. The method is universal and demonstrated by the synthesis of 12 different porous carbons with various template sources. The effects of pore geometries in catalysis can be isolated and investigated. Two of the resulted materials with different pore geometries are studied as supports for Ru clusters in the hydrogenolysis of 5-hydroxymethylfurfural (HMF) and electrochemical hydrogen evolution (HER). The porous carbon supported Ru catalysts outperform commercial ones in both reactions. It was found that Ru on bottle-neck pore carbon shows highest yield in hydrogenolysis of HMF to 2,5-dimethylfuran (DMF) due to a better confinement effect. A wide temperature operation window from 110 °C to 140 °C, with over 75% yield and 98% selectivity of DMF has been achieved. Tubular pores enable fast charge transfer in electrochemical HER, requiring only 16 mV overpotential to reach current density of 10 mA cm.	Jan 2019
I12-JEEP: Joint Engineering, Environmental and Processing	Data and videos for ultrafast synchrotron X-ray imaging studies of metal solidification under ultrasound Bing Wang , Dongyue Tan , Tung Lik Lee , Jia Chuan Khong , Feng Wang , Dmitry Eskin , Thomas Connolley , Kamel Fezzaa , Jiawei Mi Data In Brief DOI: 10.1016/j.dib.2018.01.110 Diamond Proposal Number(s): [8542] Show Abstract ▼ Abstract: The data presented in this article are related to the paper entitled ‘Ultrafast synchrotron X-ray imaging studies of microstructure fragmentation in solidification under ultrasound’ [1]. This data article provides further supporting information and analytical methods, including the data from both experimental and numerical simulation, as well as the Matlab code for processing the X-ray images. Six videos constructed from the processed synchrotron X-ray images are also provided.	Feb 2018
B18-Core EXAFS	Methanation of CO2 over Zeolite-Encapsulated Nickel Nanoparticles Farnoosh Goodarzi , Liqun Kang , Feng Ryan Wang , Finn Joensen , Søren Kegnaes , Jerrik Mielby Chemcatchem DOI: 10.1002/cctc.201701946 Diamond Proposal Number(s): [15151] Show Abstract ▼ Abstract: Here we present a simple and effective method to encapsulate Ni nanoparticles in zeolite silicalite-1. In this method, the zeolite is modified by selective desilication, which creates intra-particle voids and mesopores that facilitate the formation of small and well-dispersed nanoparticles upon impregnation and reduction. TEM and XPS analysis confirm that a significant part of the Ni nanoparticles are situated inside the zeolite rather than on the outer surface. The encapsulation results in an increased metal dispersion and, consequently, a high catalytic activity for CO2 methanation. With a gas hourly space velocity of 60000 ml/g catalyst h-1 and H2/CO2=4, the zeolite-encapsulated Ni nanoparticles result in 60% conversion at 450°C, which corresponds to a site-time yield of around 304 mol CH4/mol Ni h-1. The encapsulated Ni nanoparticles show no change in activity or selectivity after 50 h of operation, although post-catalysis characterisation reveals some particle migration.	Jan 2018
	In-situ synchrotron X-ray radiography observation of primary Al 2 Cu intermetallic growth on fragments of aluminium oxide film Feng Wang , Dmitry Eskin , Thomas Connolley , Chuangnan Wang , Billy Koe , Andrew King , Christina Reinhard , Jiawei Mi Materials Letters 213, 303 - 305 DOI: 10.1016/j.matlet.2017.11.090 Open Access Show Abstract ▼ Abstract: While using synchrotron X-ray radiography for studying ultrasonic melt processing, the growth of the primary Al2Cu intermetallic phase on fragments of aluminium oxide film during solidification of a hypereutectic Al-35% Cu alloy was observed in-situ and in real time with adequate spatial and temporal resolution. This provides the first direct evidence for the nucleation of a primary phase on oxide particles during solidification of real metallic alloys. Comparison of the primary Al2Cu intermetallics grown in the melt with and without fragments of aluminium oxide film reveals considerable refinement, which demonstrates that the enhanced nucleation of a primary phase on oxide particles promotes structure refinement.	Nov 2017
I12-JEEP: Joint Engineering, Environmental and Processing	Ultrafast synchrotron X-ray imaging studies of microstructure fragmentation in solidification under ultrasound Bing Wang , Dongyue Tan , Tung Lik Lee , Jia Chuan Khong , Feng Wang , Dmitry Eskin , Thomas Connolley , Kamel Fezzaa , Jiawei Mi Acta Materialia DOI: 10.1016/j.actamat.2017.10.067 Diamond Proposal Number(s): [8542] Show Abstract ▼ Abstract: Ultrasound processing of metal alloys is an environmental friendly and promising green technology for liquid metal degassing and microstructural refinement. However many fundamental issues in this field are still not fully understood, because of the difficulties in direct observation of the dynamic behaviours caused by ultrasound inside liquid metal and semisolid metals during the solidification processes. In this paper, we report a systematic study using the ultrafast synchrotron X-ray imaging (up to 271,554 frame per second) technique available at the Advanced Photon Source, USA and Diamond Light Source, UK to investigate the dynamic interactions between the ultrasonic bubbles/acoustic flow and the solidifying phases in a Bi-8%Zn alloy. The experimental results were complimented by numerical modelling. The chaotic bubble implosion and dynamic bubble oscillations were revealed in-situ for the first time in liquid metal and semisolid metal. The fragmentation of the solidifying Zn phases and breaking up of the liquid-solid interface by ultrasonic bubbles and enhanced acoustic flow were clearly demonstrated and agreed very well with the theoretical calculations. The research provides unambiguous experimental evidence and robust theoretical interpretation in elucidating the dominant mechanisms of microstructure fragmentation and refinement in solidification under ultrasound.	Nov 2017
	A synchrotron X-radiography study of the fragmentation and refinement of primary intermetallic particles in an Al-35Cu alloy induced by ultrasonic melt processing Feng Wang , Dmitry Eskin , Jiawei Mi , Chuangnan Wang , Billy Koe , Andrew King , Christina Reinhard , Thomas Connolley Acta Materialia DOI: 10.1016/j.actamat.2017.09.010 Open Access Show Abstract ▼ Abstract: Using synchrotron X-ray high speed radiography, the fragmentation and refinement of pre-existing primary Al2Cu intermetallic dendrites induced by ultrasonic melt processing in a hypereutectic Al-35% Cu alloy were studied in-situ and in real time. The alloy was melted, contained and processed in a quartz tube crucible with a middle section of approximately 300 μm-thick channel where the observations were made. Direct observation of intermetallic fragmentation and detachment unambiguously confirms that the acoustic cavitation and streaming flow play a crucial role in fragmentation of the intermetallic dendrites. Furthermore, the remelting effect due to transport of hot liquid via acoustic streaming flow and the stress against the intermetallic dendrites caused by acoustic streaming flow are found to be the dominant fragmentation mechanism in the present experiments. It is also suggested that cavitation bubbles or bubble clouds contribute to fragmentation not only by mechanically fracturing the dendrites but also by facilitating the effect of acoustic streaming flow on dendrites. At last, clear observation of equiaxed intermetallic dendrites growing from small fragments after ultrasonic melt processing provides the first conclusive evidence of the refinement mechanism, i.e. the acoustic cavitation and acoustic streaming flow progressively break the intermetallic dendrites into small fragments. Most of these small fragments are able to survive and then act as nuclei for the subsequent solidification of intermetallic phases, consequently leading to intermetallic refinement in the solidified microstructure.	Sep 2017
I02-Macromolecular Crystallography I03-Macromolecular Crystallography	Determinants of the Inhibition of DprE1 and CYP2C9 by Antitubercular Thiophenes Renhe Liu , Xiaoxuan Lyu , Mei-hui Hsu , Catherine Vilcheze , Scott G. Franzblau , William R. Jacobs , Gurdyal S. Besra , Eric F. Johnson , Klaus Futterer , Feng Wang Angewandte Chemie International Edition DOI: 10.1002/anie.201707324 Diamond Proposal Number(s): [8359] Show Abstract ▼ Abstract: Mycobacterium tuberculosis (Mtb) DprE1, an essential isomerase for the biosynthesis of the mycobacterial cell wall, is a validated target for tuberculosis (TB) drug development. Here we report the X-ray crystal structures of DprE1 and the DprE1 resistant mutant (Y314C) in complexes with TCA1 derivatives to elucidate the molecular basis of their inhibitory activities and an unconventional resistance mechanism, which enabled us to optimize the potency of the analogs. The selected lead compound showed excellent in vitro and in vivo activities, and low risk of toxicity profile except for the inhibition of CYP2C9. A crystal structure of CYP2C9 in complex with a TCA1 analog revealed the similar interaction patterns to the DprE1-TCA1 complex. Guided by the structures, an optimized molecule was generated with differential inhibitory activities against DprE1 and CYP2C9, which provides insights for development of a clinical candidate to treat TB.	Aug 2017
	Influence of ultrasonic treatment on formation of primary Al 3 Zr in Al?0.4Zr alloy Feng Wang , D. Eskin , T. Connolley , Jia-wei Mi Transactions Of Nonferrous Metals Society Of China 27, 977 - 985 DOI: 10.1016/S1003-6326(17)60115-8 Show Abstract ▼ Abstract: The effect of ultrasonic treatment on the formation of primary Al3Zr was investigated by applying ultrasound to an Al–0.4Zr alloy. Three temperature ranges were selected, i.e., 830 to 790 °C (above liquidus), 790 to 750 °C (cross liquidus) and 750 to 710 °C (below liquidus) for ultrasonication. Using the scanning electron microscopy, both the size and morphology of the primary Al3Zr particles were examined. It was found that the size was significantly reduced and the morphology changed from large throwing-star shape to small compact tablet shape. The mechanisms for refinement of primary Al3Zr were discussed. It is suggested that sonocrystallization theory via activation of aluminium oxide particles is responsible for the refinement of primary Al3Zr when ultrasonic melt treatment (UST) is applied within the fully liquid state. The refinement of primary Al3Zr particles when UST is applied in the slurry (growth stage) is due to the sonofragmentation.	May 2017
	In-situ observation of ultrasonic cavitation-induced fragmentation of the primary crystals formed in Al alloys Feng Wang , Iakovos Tzanakis , Dmitry Eskin , Jiawei Mi , Thomas Connolley Ultrasonics Sonochemistry DOI: 10.1016/j.ultsonch.2017.03.057 Open Access Show Abstract ▼ Abstract: The cavitation-induced fragmentation of primary crystals formed in Al alloys were investigated for the first time by high-speed imaging using a novel experimental approach. Three representative primary crystal types, Al3Ti, Si and Al3V with different morphologies and mechanical properties were first extracted by deep etching of the corresponding Al alloys and then subjected to ultrasonic cavitation processing in distilled water. The dynamic interaction between the cavitation bubbles and primary crystals was imaged in-situ and in real time. Based on the recorded image sequences, the fragmentation mechanisms of primary crystals were studied. It was found that there are three major mechanisms by which the primary crystals were fragmented by cavitation bubbles. The first one was a slow process via fatigue-type failure. A cyclic pressure exerted by stationary pulsating bubbles caused the propagation of a crack pre-existing in the primary crystal to a critical length which led to fragmentation. The second mechanism was a sudden process due to the collapse of bubbles in a passing cavitation cloud. The pressure produced upon the collapse of the cloud promoted rapid monotonic crack growth and fast fracture in the primary crystals. The third observed mechanism was normal bending fracture as a result of the high pressure arising from the collapse of a bubble cloud and the crack formation at the branch connection points of dendritic primary crystals. The fragmentation of dendrite branches due to the interaction between two freely moving dendritic primary crystals was also observed. A simplified fracture analysis of the observed phenomena was performed. The specific fragmentation mechanism for the primary crystals depended on their morphology and mechanical properties.	Apr 2017

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