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Layered Li(Co_1−xAl_x)O₂, x=0.05-0.25 phases have been prepared by using the one-pot molten salt method at 850 °C in air and characterized by X-ray diffraction, Rietveld refinement, SEM-EDAX, chemical analysis, BET surface area and density methods. Cathodic properties were studied at ambient temperature in cells with Li-metal as the counter electrode by cyclic voltammetry (CV), galvanostatic charge-discharge cycling (up to 130 cycles) and Impedance spectroscopy. Single-phase compounds with hexagonal layer structure formed for all x. Results showed that for x≥0.05, the Li-de-intercalation potential during the first charge-cycle occurs at a value slightly higher than that shown by pure LiCoO₂ and the structural transitions that occur at ∼4.1 V and ∼ 4.2 V are suppressed. However, the transition at ∼4.5 V is not suppressed. As a consequence, the long-term cyclability of Li(Co_1−xAl_x)O₂ is greatly improved, when cycled in the potential ranges 2.5-4.3 V and 2.5-4.4 V at the current rate of 30 mA/g. Higher 10^th cycle capacities were noted for x≥0.1-0.2 in the 2.5-4.5 V range but capacity-fading was noted, by 5-7 % at the end of 55 cycles. The observed CV and impedance data have been analyzed and interpreted.

The electron beam induced deposition (EBID) originated contamination writing as early as 1934, and many studies have been carried out using scanning electron microscopes for various gases and conditions, and the technique was found to be very successful for a number of applications making variously shaped nano-structures. Therefore, EBID is recognized as a very promising nanofabrication technique and the amount of work devoted to this field is rapidly increasing. In this chapter, fundamentals and an overview of EBID are given in [Section Number of FUNDAMENTALS]. Recent progress is discussed in [Section Number of RECENT RESEARCH ACTIVITIES] which includes consideration of resolution improvement using 200 kV scanning transmission electron microscopy, the Monte Carlo-based calculation of a deposit shape, nanowiring and electron conductivities, three-dimensional structure fabrication, magnetic material deposition, and further trials to improve the range of material choices and the fabrication speed.

We have dedicated a new experiment to remeasuring the ternary α-particle energy spectrum in ²⁵²Cf spontaneous fission using an array of unshielded silicon detectors and unambiguously discriminating α-particles from neighboring isotopes by time-of-flight (TOF) techniques using fission fragments as the start. Particle detectors were placed at right angle to fission fragment direction, so mainly equatorial particles are registered. Compared to many previous ΔE-E experiments which feature detection thresholds at 6 to 9 MeV, the energy distribution of ternary α-particles could, for the first time, be measured down to 1 MeV. Furthermore, the energy spectrum of ⁶He could be analyzed, albeit with weak statistics, and the yield ratio ⁶He/⁴He was deduced. For both, ⁴He and ⁶He, an excess in the yield as compared to a Gaussian shape is observed at energies below 9 MeV. Corrections to the measured α-spectrum were made for both, the wider than detected angular interval of equatorial particles (50° ≤ Θ_αL ≤ 130°) and the full span of angles, including polar emission, eventually measured in experiments without fragment coincidences. For this purpose, we determined our constraint in detection angle by Monte-Carlo and employed data on the energy dependent angular distribution of the α-particles obtained by P. Heeg with DIOGENES. The emission angle was found to affect mainly the width of the energy distribution, by up to 1 MeV. We compare our results with literature data, and discuss prospects for future measurements.

Although the recoil mass-separator LOHENGRIN at Institute Laue-Langevin was originally designed for the spectrometry of binary fission fragments, it was also used in the past for measuring light-charged particles from ternary fission. However, due to limited electric field settings the energy distribution of the lightest particles was not completely accessible. In this contribution we report on an energy degrader technique that allows the measurement of the entire energy spectra of ternary particles with LOHENGRIN. We demonstrate how the measured particle spectra are distorted by the energy degrader and present results from a Monte Carlo simulation that shows how the original energy distributions are reconstructed. Finally, we apply this procedure to experimental data of ternary particles from the reaction ²³⁵U(n_th, f).

The low background DAMA/NaI experiment (≃ 100 kg highly radiopure NaI(Tl)) at the Gran Sasso National Laboratory of the I.N.F.N. had the unique feature to effectively investigate the presence of Dark Matter particle in the galactic halo by exploiting the model independent annual modulation signature. This experiment has collected data over seven annual cycles for a total exposure of more than 10⁵kg × day and has pointed out at 6.3 σ C.L. a modulation effect satisfying all the many peculiarities of the signature. Neither systematics nor side reactions able to account for the observed effect were found. Several (but still few with respect to the many possibilities) corollary model dependent quests for the candidate particle have also been carried out. At present the second generation DAMA/LIBRA set-up (≃ 250 kg highly radiopure NaI(Tl)) is in operation. A R&D towards possible ultimate 1 ton NaI(Tl) experiment is also in progress.

Several g factors of excited states of moderately neutron-rich ²⁵²Cf fission fragments were measured using the IPAC method from data gathered with the GAMMASPHERE array. These results shine new light onto two regions of the nuclear chart very sensitive to the number of valence nucleons. The results for ¹⁰¹Zr and ^103,105Mo focus on the single particle properties of nuclei in a region characterised by rapid shape changes and the emergence of triaxiality, and were found consistent with a particle–rotor picture. The g factors of ^138,140,142Xe constitute an excellent test of single–particle properties near the N=82 shell closure. The measured g factors are in excellent agreement with recent shell-model and QRPA calculations.

We have dedicated a new experiment to remeasuring the ternary α-particle energy spectrum in ²⁵²Cf spontaneous fission using an array of unshielded silicon detectors and unambiguously discriminating α-particles from neighboring isotopes by time-of-flight techniques using fission fragments as the start. Compared to many previous experiments, which entailed detection thresholds of 6 to 9 MeV α-particle energy due to the ∆E-E method applied and use of protection foils on detectors, the energy distribution of ternary α-particles could, for the first time, be measured down to 1 MeV. Furthermore, the energy spectrum of ⁶He could be analysed, albeit with weak statistics, and the yield ratio ⁶He/⁴He was deduced. For ⁴He, an excess in the yield as compared to a Gaussian shape is observed at energies below 9 MeV whose magnitude is in close agreement with data presented by Tishchenko et al. in 2002. On the other hand, the data formerly published by Loveland in 1974 exceed the low-energy yield of ternary α particles by up to a factor of two. We present our results on the ternary α-particle spectrum, and also the data on ⁶He, and discuss prospects for future measurements.

Lithium niobate hollow spheres and octahedra with rough surface have been successfully fabricated from a novel H₂(H₂O)Nb₂O₆ precursor by in situ combustion treatment. X-ray diffraction and scanning electronic microscopy were used to study the phase composition and microstructure of the obtained lithium niobate. Experimental results demonstrated that H₂(H₂O)Nb₂O₆ hollow spheres and octahedra can be facilely transformed into hexagonal phase LiNbO₃ crystallites without destroying the microstructures, even though through an intense combustion treatment. These hollow and rough octahedral structures may open up large perspectives for LiNbO₃. The present in situ conversion strategy by coating flexible H₂(H₂O)Nb₂O₆ precursors to form microscopic reactors, could also be extended to other niobates with various structures.

A new and facial method to directly synthesize stable and crystalline pure phase Ni(OH)₂ nanosheets was developed using cationic surfactant (cetyltrimethylammonium bromide, CTAB). The advantages of the method are facile synthesis, at low temperature (room temperature and 60 °C), and low cost. The results revealed that all the products were flake-like nanosheets with typical length in the range of several hundreds nanometers and width in the range of several to several tens nanometers. A possible formation mechanism is preliminary proposed for the formation of the nanostructure. It is considered that this simple aqueous solution synthetic route can be applied as a general method for the preparation of other metal hydroxides with nanosheets.