Yrast levels of 220Ra populated in the 208Pb(14C, 2n) reaction

Yrast states in the nucleus ²²⁰Ra were studied by means of the ²⁰⁸Pb(¹⁴C, 2n) reaction at 61 and 64 MeV. A staggering sequence of levels of positive and negative parity has been observed up to spin and parity I^π = 16⁺ (18 ⁺) and from I^π = 5^? to I^π = 17^?, respectively. These states are connected by strong E1 transitions competing with the stretched E2 transitions, the $\text{B(}\text{E}\text{1)}\text{B(}\text{E}\text{2)}$ ratio being ~ 10 ^?6 fm^?2. The ratio of the excitation energy of the 4⁺ state to that of the 2⁺ state is close to the vibrational limit. The moment of inertia associated with the negative-parity yrast states is slightly increasing with the rotational frequency ω. It is considerably higher than that of the positive-parity states at lower spins, the difference decreasing monotonically with increasing ω. The data are discussed with reference to the octupole vibrational picture as well as to the results of recent models predicting reflection-asymmetric shapes in the Ra-Th region.     

Tables for Numerical Integration

Journal of the Operational Research Society -     

Vibrational frequencies associated with the inter-stitial carbon atoms in the large metal cluster complexes (NMe4)2[Os10C(CO)24] and H2Os10C(CO)24

Determination of the vibrational frequencies of the interstitial carbon atoms in the metal clusters [Os₁₀C(CO)₂₄]^2? and H₂Os₁₀C(CO)₂₄, confirmed in the latter by ¹³C enrichment, shows that the protonated cluster species exhibits considerable deviation from pseudo-cubic symmetry in the crystal, in contrast to the dianion.     

A Nanocage for Nanomedicine: Polyhedral Oligomeric Silsesquioxane (POSS)

Ground‐breaking advances in nanomedicine (defined as the application of nanotechnology in medicine) have proposed novel therapeutics and diagnostics, which can potentially revolutionize current medical practice. Polyhedral oligomeric silsesquioxane (POSS) with a distinctive nanocage structure consisting of an inner inorganic framework of silicon and oxygen atoms, and an outer shell of organic functional groups is one of the most promising nanomaterials for medical applications. Enhanced biocompatibility and physicochemical (material bulk and surface) properties have resulted in the development of a wide range of nanocomposite POSS copolymers for biomedical applications, such as the development of biomedical devices, tissue engineering scaffolds, drug delivery systems, dental applications, and biological sensors. The application of POSS nanocomposites in combination with other nanostructures has also been investigated including silver nanoparticles and quantum dot nanocrystals. Chemical functionalization confers antimicrobial efficacy to POSS, and the use of polymer nanocomposites provides a biocompatible surface coating for quantum dot nanocrystals to enhance the efficacy of the materials for different biomedical and biotechnological applications. Interestingly, a family of POSS‐containing nanocomposite materials can be engineered either as completely non‐biodegradable materials or as biodegradable materials with tuneable degradation rates required for tissue engineering applications. These highly versatile POSS derivatives have created new horizons for the field of biomaterials research and beyond. Currently, the application of POSS‐containing polymers in various fields of nanomedicine is under intensive investigation with expectedly encouraging outcomes.

     

Optical Properties of Micro-patterned Silver Nanoparticle Substrates

In this paper, we describe a novel technique for depositing metal nanoparticles (NPs) on a planar substrate whereby the NPs are micro-patterned on the surface by a simple stamp-printing procedure. The method exploits the attractive force between negatively charged colloidal metal NPs and positively-charged polyelectrolyte layers which have been selectively deposited on the surface. Using this technique, large uniform areas of patterned metal NPs, with different plasmonic properties, were achieved by optimisation of the stamping process. We report the observation of unusual fluorescence emission from these structures. The emission was measured using epifluorescence microscopy. Fluorescence lifetime behaviour was also measured. Furthermore, the μ-patterned NPs exhibited blinking behaviour under 469 nm excitation and the fluorescence spectrum was multi-peaked. It has been established that the fluorescence is independent of the plasmon resonance properties of the NPs. As well as optimising the novel NP μ-patterning technique, this work discusses the origin and characteristics of the anomalous fluorescence behaviour in order to characterise and minimise this unwanted background contribution in the use of metal NPs for plasmonic enhancement of fluorescence for optical biochip applications.     

Advances in biological NMR circa WWMR 2010 in Florence

We summarize the advances and breakthroughs of 'biological' NMR that were presented at the Joint EUROMAR 2010 - 17th ISMAR Conference - aka 'World Wide Magnetic Resonance 2010' in Florence, Italy.     

Negative-muon capture in <Superscript>150</Superscript>Sm

The energy and time spectra of γ rays emitted during negative-muon capture in ¹⁵⁰Sm were studied. The total muon lifetime in ¹⁵⁰Sm was measured. The yields of several radioactive isotopes in this reaction were determined. The partial γ-ray yield upon muon capture by a ¹⁵⁰Sm nucleus were measured.