Formation of octapod MnO nanoparticles with enhanced magnetic properties through kinetically-controlled thermal decomposition of polynuclear manganese complexes

Polynuclear manganese complexes are used as precursors for the synthesis of manganese oxide nanoparticles (MnO NPs). Altering the thermal decomposition conditions can shift the nanoparticle product from spherical, thermodynamically-driven NPs to unusual, kinetically-controlled octapod structures. The resulting increased surface area profoundly alters the NP's surface-dependent magnetism and may have applications in nanomedicine

Stringy Instantons in SU(N) N=2 Non-Conformal Gauge Theories

In this paper we explicitly obtain the leading corrections to the SU(N) N=2 prepotential due to stringy instantons both in flat space-time and in the presence of a non-trivial graviphoton background field. We show that the stringy corrections to the prepotential are expressible in terms of the elementary symmetric polynomials. For N>2 the theory is not conformal; we discuss the introduction of an explicit dependence on the string scale \alpha' in the low-energy effective action through the stringy non-perturbative sector.Comment: 22 pages, 1 figur

Seiberg-Witten prepotential for E-string theory and global symmetries

We obtain Nekrasov-type expressions for the Seiberg-Witten prepotential for the six-dimensional (1,0) supersymmetric E-string theory compactified on T^2 with nontrivial Wilson lines. We consider compactification with four general Wilson line parameters, which partially break the E_8 global symmetry. In particular, we investigate in detail the cases where the Lie algebra of the unbroken global symmetry is E_n + A_{8-n} with n=8,7,6,5 or D_8. All our Nekrasov-type expressions can be viewed as special cases of the elliptic analogue of the Nekrasov partition function for the SU(N) gauge theory with N_f=2N flavors. We also present a new expression for the Seiberg-Witten curve for the E-string theory with four Wilson line parameters, clarifying the connection between the E-string theory and the SU(2) Seiberg-Witten theory with N_f=4 flavors.Comment: 22 pages. v2: comments and a reference added, version to appear in JHE

Concert recording 2022-04-28

[Track 1]. Por una cabeza / Carlos Gardel ; arr. Dominic Na ; [Track 2]. Concerto in G minor for two cellos, RV. 531. I. Allegro / Antonio Vivaldi ; arr. Dominic Na ; [Track 3]. Sonata in G major. I. Allegro non troppo / Giovanni Battista Sammartini ; arr. Dominic Na ; [Track 4]. Salut d\u27amour, op. 12 / Edward Elgar ; arr. Dominic Na ; [Track 5]. Adoration / Florence Price ; arr. Dominic Na ; [Track 6]. Kol Nidrei, op. 47 / Max Bruch ; arr. Dominic Na ; [Track 7]. Concerto in G minor for two cellos, RV. 531. I. Adagio-moderato, Allegro molto / Antonio Vivaldi ; arr. Dominic Na ; [Track 8]. Liebesfreud from Three old Viennese dances. I. Allegro / Fritz Kreisler ; arr. Dominic Na

Concert recording 2022-04-28

[Track 1]. Por una cabeza / Carlos Gardel ; arr. Dominic Na ; [Track 2]. Concerto in G minor for two cellos, RV. 531. I. Allegro / Antonio Vivaldi ; arr. Dominic Na ; [Track 3]. Sonata in G major. I. Allegro non troppo / Giovanni Battista Sammartini ; arr. Dominic Na ; [Track 4]. Salut d\u27amour, op. 12 / Edward Elgar ; arr. Dominic Na ; [Track 5]. Adoration / Florence Price ; arr. Dominic Na ; [Track 6]. Kol Nidrei, op. 47 / Max Bruch ; arr. Dominic Na ; [Track 7]. Concerto in G minor for two cellos, RV. 531. I. Adagio-moderato, Allegro molto / Antonio Vivaldi ; arr. Dominic Na ; [Track 8]. Liebesfreud from Three old Viennese dances. I. Allegro / Fritz Kreisler ; arr. Dominic Na

Effect of nickel on the microstructure and mechanical property of die-cast Al–Mg–Si–Mn alloy

The effect of nickel on the microstructure and mechanical properties of a die-cast Al–Mg–Si–Mn alloy has been investigated. The results show that the presence of Ni in the alloy promotes the formation of Ni-rich intermetallics. These occur consistently during solidification in the die-cast Al–Mg–Si–Mn alloy across different levels of Ni content. The Ni-rich intermetallics exhibit dendritic morphology during the primary solidification and lamellar morphology during the eutectic solidification stage. Ni was found to be always associated with iron forming AlFeMnSiNi intermetallics, and no Al3Ni intermetallic was observed when Ni concentrations were up to 2.06 wt% in the alloy. Although with different morphologies, the Ni-rich intermetallics were identified as the same AlFeMnSiNi phase bearing a typical composition of Al[100–140](Fe,Mn)[2–7]SiNi[4–9]. With increasing Ni content, the spacing of the α-Al–Mg2Si eutectic phase was enlarged in the Al–Mg–Si–Mn alloy. The addition of Ni to the alloy resulted in a slight increase in the yield strength, but a significant decrease in the elongation. The ultimate tensile strength (UTS) increased slightly from 300 to 320 MPa when a small amount (e.g. 0.16 wt%) of Ni was added to the alloy, but further increase of the Ni content resulted in a decrease of the UTS.The Engineering and Physical Sciences Research Council (EPSRC), Technology Strategy Board (TSB) and Jaguar Land Rover (JLR) in the United Kingdom

5-dim Superconformal Index with Enhanced En Global Symmetry

The five-dimensional $\mathcal{N}=1$ supersymmetric gauge theory with Sp(N) gauge group and SO(2N_f) flavor symmetry describes the physics on N D4-branes with $N_f$ D8-branes on top of a single O8 orientifold plane in Type I' theory. This theory is known to be superconformal at the strong coupling limit with the enhanced global symmetry $E_{N_f+1}$ for $N_f\le 7$. In this work we calculate the superconformal index on $S^1\times S^4$ for the Sp(1) gauge theory by the localization method and confirm such enhancement of the global symmetry at the superconformal limit for $N_f\le 5$ to a few leading orders in the chemical potential. Both perturbative and (anti)instanton contributions are present in this calculation. For $N_f=6,7$ cases some issues related the pole structure of the instanton calculation could not be resolved and here we could provide only some suggestive answer for the leading contributions to the index. For the Sp(N) case, similar issues related to the pole structure appear.Comment: 70 pages, references added, published versio

Burying the 'refuse revolution': the rise of controlled tipping in Britain 1920-1960

The definitive, peer-reviewed and edited version of this article is published in Environment and Planning A, 42, 5, 1033-1048, 2010, 10.1068/a42120.This paper investigates the emergence of ‘controlled tipping’ as the dominant method of municipal waste disposal in Britain between 1920 and 1960. The triumph of controlled tipping, despite the availability of alternative disposal technologies, needs to be understood in the context of the contested meanings of ‘waste’ and ‘wasteland’, which helped to determine attitudes and approaches to disposal. Following the conclusion of the First World War there was an urgent requirement for a cheap means of disposing of increasing amounts of urban municipal waste. The obvious choice was tipping. Before the war, however, refuse tipping had been rejected as insanitary by the emerging waste disposal profession. Public cleansing professionals therefore had to recuperate tipping as a medically and environmentally benign mode of disposal that was reconcilable with the needs of sanitary science and landscape preservation. Controlled tipping, with its combined claims to scientific progress and the revalorization of refuse, enabled dumping to be successfully re-produced as the dominant mode of municipal refuse disposal in Britain. However, tipping faced further challenges after 1945 from changing popular understandings of the value of ‘derelict’ landscapes and from the politics of amenity. The ‘refuse revolution’ was a work in progress