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The L i ( i  = 1–3) subshell integral X-ray fluorescence (XRF) cross sections have been measured for 17 elements with 33 ≤  Z  ≤ 51 following photoionization by the Mn K X-rays ( E Kαβ  = 5.96 keV). The L i ( i  = 1–3) subshell X-rays were measured using a low-energy Ge (LEGe) detector at an emission angle, ψ  = 125°, where angle-dependent emission effects, if any, are nullified as P 2 (cos  ψ ) ∼ 0. The XRF cross sections were interpreted in terms of available sets of theoretical L i ( i  = 1–3) subshell photoionization cross sections, radiative transition probabilities, and the atomic vacancy decay parameters, namely, fluorescence ( ω i ) and Coster-Kronig ( f ij ) yields. A set of L 1 subshell fluorescence ( ω 1 ) yields was deduced for the elements with 37 ≤  Z  ≤ 51 from the present measured Lγ 2,3,(4) [ L 1 - N 2,3 ( O 2,3 )] XRF cross sections. The ω 1 values exhibit jumps at Z  = 40 and 49, which are identified to be due to cut-off of the L 1 L 2 M 4,5 and L 1 L 3 M 4,5 Coster-Kronig (CK) transitions predicted by calculations based on relativistic Dirac-Hartree-Slater (RDHS) model. However, the measured ω 1 values are found to differ considerably from those based on the RDHS model calculations for the elements below Z  = 50. The pronounced discrepancies between measured and theoretical ω 1 values are likely to be due to overestimation of the L 1 - L 2,3 M 4,5 CK transition rates by a factor of ∼2–3. Our experiential results demand consideration of extra-atomic relaxation from the solid-state effects and exchange splitting in many-body theoretical calculations of the low-energy CK transitions. [ABSTRACT FROM AUTHOR]

Li depth profiles in Au/Si/LiPON/LCO/Au (LCO = LiCoO 2 , LiPON = Li 3.3 PO 3.8 N 0.2 ) thin films battery under charging condition, prepared on self-supporting Al substrate, have been in situ measured by means of transmission elastic recoil detection (TERD) and Rutherford backscattering spectroscopy (RBS) techniques not only with 5.4 MeV He 2+ ion beam without absorber, but also 9 MeV O 4+ ion beam with Al absorber. In experiments with 5.4 MeV He 2+ , well-resolved step-wise TERD spectra have been observed, from which thickness and Li composition of constituent films of the battery are directly estimated. The Li transport from LCO to Si films through LiPON as well as return-back of Li from Si to LCO films and Li leakage into the Al substrate out of the battery system by over-charging under charging condition have been observed in the experiments both 5.4 MeV He 2+ and 9 MeV O 4+ . The latter result indicates that these techniques are applicable to testing degradation of the battery performance by repetition of charging and discharging. Both results are compared in details with each other. [ABSTRACT FROM AUTHOR]

The line for the pulsed beam of the 3 MeV Tandetron accelerator at LABEC (Florence) has been upgraded for ion implantation experiments aiming at the fabrication of single-photon emitters in a solid-state matrix. A system based on Al attenuators has been calibrated in order to extend the energy range of the implanted ions from MeV down to the tens of keV. A new motorized XY stage has been installed in the implantation chamber for achieving ultra-fine control on the position of each implanted ion, allowing to reach the scale imposed by lateral straggling. A set-up for the activation of the implanted ions has been developed, based on an annealing furnace operating under controlled high-vacuum conditions. The first experiments have been performed with silicon ions implanted in diamond and the luminescent signal of the silicon-vacancy (SiV) center, peaked at 738 nm, has been observed for a wide range of implantation fluences (10 8  ÷ 10 15  cm −2 ) and implantation depths (from a few nm to 2.4 µm). Studies on the efficiency of the annealing process have been performed and the activation yield has been measured to range from 1% to 3%. The implantation and annealing facility has thus been tuned for the production of SiV centers in diamond, but is in principle suitable for other ion species and solid-state matrices. [ABSTRACT FROM AUTHOR]

Makrofol DE 1-1 is a recent type of solid state nuclear track detectors could be used to measure radon concentration in the environment throughout the detection of α-particles emitted from radon decay. Thus, studying the physical parameters that control the formation of alpha tracks is vital for environmental radiation protection. Makrofol DE 1-1 polycarbonate detector was irradiated by α-particles of energies varied from 2 to 5 MeV emitted from the 241 Am source of α-particle energy of 5.5 MeV. Then, the detector was etched in an optimum etching solution of mixed ethyl alcohol in KOH aqueous solution of (85% (Vol.) of 6 M KOH + 15% (Vol.) C 2 H 5 OH) at 50 °C for 3 h. Afterward, the bulk etch rate, etching sensitivity, and the registration efficiency of the detector, which control the tracks registration, were measured. The bulk etch rate of Makrofol detector was found to be 3.71 ± 0.71 μm h −1 . The etching sensitivity and the detector registration efficiency were decreased exponentially with α-particles’ energies following Bragg curve. A precise registration of α-particle was presented in this study. Therefore, Makrofol DE 1-1 can be applied as a radiation dosimeter as well as radon and thoron monitors. [ABSTRACT FROM AUTHOR]

Thermal stability of coatings is of crucial importance for reliability of electronic devices operating at high temperature. Thus, we investigated the Cr–Pt system where a thin platinum coating of 0.1 μm was deposited on chromium substrate and annealed at 1000 °C for 8 h. The scanning electron microscope (SEM) showed that a continuous and uniformly deposited Pt coating experienced the formation of “islands” after annealing. The grain-boundary grooving, dewetting and agglomeration were the main mechanisms of degradation of thermally annealed coatings. Results by μ-PIXE (particle-induced X-ray emission) and transmission electron microscope (TEM) showed the presence of Cr 3 Pt phase in “islands” and the coating thickness was approximately 0.5 μm. The surrounding regions were left uncovered due to coating agglomeration at the expense of initially deposited coating. [ABSTRACT FROM AUTHOR]

Solid state reactions between a thin film (133nm) of Zr and bulk single crystalline 6H-SiC substrates have been studied at temperatures between 600°C and 850°C for durations of 30, 60 and 120min under high vacuum conditions. The deposited film and reaction zones were investigated by Rutherford backscattering spectrometry (RBS) and X-ray diffraction. The RBS spectra were simulated in order to obtain the deposited layer thickness, reaction zone compositions and reaction zone thickness. The as-deposited spectra fit well with those annealed at 600°C, thus showing there were no reactions taking place. At temperatures of 700°C and above, Zr reacted with the SiC substrate and formed a mixed layer of Zr carbide (ZrC x ) and Zr silicides (ZrSi, Zr2Si and Zr5Si3). Annealing at 850°C for 240min revealed that all the deposited Zr had completely reacted. The interface reaction follows the parabolic growth law thereby indicating diffusion controlled reaction kinetics. The activation energy for the diffusion process obtained was 1.6eV in the relatively narrow temperature range 700–850°C. [ABSTRACT FROM AUTHOR]

Abstract: In this paper we present the formation of carbon nanowires (polyynes and polycumulenes) in the solid state by ion irradiation of frozen hydrocarbons (C6H6 and C2H2). Irradiations have been performed using H+ ions in the 100’skeV energy regime using fluences up to 5×1014 ions/cm2. Beyond the intrinsic significance of these results in the field of material science, this work has been motivated by the fact that ion beam irradiation of hydrocarbon ices is one of the most important process thought to happen in several extraterrestrial environments where many spectroscopic features of polyyne molecules have been identified. [Copyright &y& Elsevier]

Abstract: Many areas of medicine such as tissue engineering requires not only mastery of modification techniques but also thorough knowledge of the interaction of cells with solid state substrates. Plasma treatment can be used to effective modification, nanostructuring and therefore can significantly change properties of materials. In this work the biocompatibility of the plasma nanostructured biopolymers substrates was studied. Changes in surface chemical structure were studied by X-ray photoelectron spectroscopy (XPS). The morphology pristine and modified samples were determined using atomic force microscopy (AFM). The surface wettability was determined by goniometry from contact angle. Biocompatibility was determined by in vitro tests, the rat vascular smooth muscle cells (VSMCs) were cultivated on the pristine and plasma modified biopolymer substrates. Their adhesion, proliferation, spreading and homogeneous distribution on polymers was monitored. It was found that the plasma treatment leads to rapid decrease of contact angle for all samples. Contact angle decreased with increasing time of modification. XPS measurements showed that plasma treatment leads to changes in ratio of polar and non-polar groups. Plasma modification was accompanied by a change of surface morphology. Biological tests found that plasma treatment have positive effect on cells adhesion and proliferation cells and affects the size of cell’s adhesion area. Changes in plasma power or in exposure time influences the number of adhered and proliferated cells and their distribution on biopolymer surface. [Copyright &y& Elsevier]

Abstract: Radioactive decay within the solid state creates chemical environments which are typically incommensurate with the initial host structure. Using a combined theoretical and computational approach, we discuss this ‘transmutation problem’ in the context of the short-lived fission products Cs-137 and Sr-90. We show how a Kröger–Vink treatment is insufficient for understanding defects arising from transmutation, and present density functional theory data for chemical evolution within two prototypical hosts, CsCl and SrTiO3. While the latter has a strong driving force for phase separation with increasing Zr content, the Cs(Ba)Cl system is surprisingly stable. The sharp difference between these two findings points to the need for better understanding of novel chemistry in nuclear waste forms. [ABSTRACT FROM AUTHOR]

Abstract: Ferrite of system, namely Ni1− x Zn x Fe2O4 with x =(0.0,0.2,0.4,0.6,0.8,1.0), have been prepared by solid state reaction to investigate the effect of gamma rays irradiations using Co60 source on the cation distribution, structural and magnetic properties. The unirradiated and irradiated samples were then subjected to characterization techniques such as X-ray diffraction, magnetization and AC susceptibility. The results of these characterizations are found to be different for irradiated from that of the pristine sample. The modifications in respect of irradiated samples are explained in terms of the ion-induced disorder. The important result of γ-irradiation on the cation distribution, structural and magnetic properties is the change of ratio Fe2+/Fe3+. Possible reasons on the results are proposed. [ABSTRACT FROM AUTHOR]

Abstract: CuIn3S5 and CuIn7S11 powders were prepared by solid-state reaction method using high-purity elemental copper, indium and sulphur. The films prepared from CuIn3S5 and CuIn7S11 powders were grown by thermal evaporation under vacuum (10−6 Torr) on glass substrates at different substrate temperature Ts varying from room temperature to 200°C. The powders and thin films were characterized for their structural properties by using X-ray diffraction (XRD) and energy dispersive X-ray (EDX). Both powders were polycrystalline with chalcopyrite and spinel structure, respectively. From the XRD data, we calculated the lattice parameters of the structure for the compounds. For CuIn3S5 powder, we also calculated the cation–anion bond lengths. The effect of substrate temperature Ts on the structural properties of the films, such as crystal phase, preferred orientation and crystallinity was investigated. Indeed, X-ray diffraction analysis revealed that the films deposited at a room temperature (30°C) are amorphous in nature while those deposited on heated were polycrystalline with a preferred orientation along (112) of the chalcopyrite phase and (311) of the spinel phase for CuIn3S5 and CuIn7S11 films prepared from powders, respectively. The morphology of the films was determined by atomic force microscopy AFM. The surface roughness and the grain size of the films increase on increasing the substrate temperature. [Copyright &y& Elsevier]

Abstract: A flow-mode integrated sampler consisting of a wire-mesh and filter-paper array along with passive solid state nuclear track detectors has been developed for estimating unattached and attached fraction of 222Rn/220Rn progeny concentration. The essential element of this sampler is the direct 222Rn/220Rn progeny sensor (DRPS/DTPS), which is an absorber-mounted-LR115 type nuclear track detector that selectively registers the alpha particles emitted from the progeny deposited on its surface. During sampling at a specified flow-rate, the unattached progeny is captured on the wire-mesh; while the attached progeny gets transmitted and is captured on the filter-paper. The alpha particles emitted by the deposited progeny atoms are registered on the sensors placed at a specified distance facing the wire-mesh and the filter-paper, respectively. The various steps involved in the development of this flow-mode direct progeny sampler such as the optimization of the sampling rate and the distance between the sensor and the deposition substrate are discussed. The sensitivity factor of the DTPS-loaded sampler for 220Rn progeny deposited on the wire-mesh and filter-paper is found to be 23.77±0.64 (trackcm−2 h−1) (Bqm−3)−1 and 22.30±0.18 (trackcm−2 h−1) (Bqm−3)−1, respectively; while that of DRPS-loaded sampler for 222Rn progeny deposition, is 3.03±0.14 (trackcm−2 h−1) (Bqm−3)−1 and 2.08±0.07 (trackcm−2 h−1) (Bqm−3)−1, respectively. The highlight of this flow-mode sampler is its high sensitivity and that it utilizes the passive technique for estimating the unattached and attached progeny concentration, thus doing away with the alpha counting procedures. [Copyright &y& Elsevier]

AlGaAs distributed Bragg reflector (DBR) structures isolation by proton irradiation was studied. The evolution of n- and p-type DBR structures lateral sheet resistance with the irradiated proton dose was measured. The vertical isolation behavior was also obtained and compared to the lateral one. No significant differences were observed. The implantation maximum energy for these structures was estimated. Thermal stability of DBR vertical isolation was studied. A 500 °C stability was obtained for samples implanted to a dose 2.5 times greater than the threshold dose of isolation. [Copyright &y& Elsevier]

CR-39 dosimeters are becoming popular in the field of solid state nuclear track detectors due to their low cost and high degree of reproducibility. Various workers have tried to use these detectors to study the low-LET ionizing radiations (i.e. UV, X-rays, electrons and gamma rays). A study has been made on the UV–VIS spectra and etching characteristics of CR-39 plastics irradiated with 150 W infrared radiation lamp for different times ranging from 0 to 24 h. The effects include the changes in bulk etch rate and sensitivity along with the improvements in absorbance of CR-39 plastic track detector. [Copyright &y& Elsevier]

The effectiveness of reflEXAFS as a probe for the very initial stages of solid-state reactions has been investigated by studying the local chemical environment of Ni during the reaction of a 150 A˚ thick film of NiO deposited onto Al2O3. The reaction to give the spinel phase requires temperatures about 1000 °C, and reaction progress degrees could be obtained by increasing the firing time at high temperature. At lower temperatures (≅930 °C), a structural rearrangement in the NiO film could be detected, seemingly related to the process by which local chemical equilibrium is attained at the interface. This should be regarded as the very early stage of the solid-state reaction and therefore this experiment proves the feasibility of a reflEXAFS investigation on these aspects of solid-state chemistry. [Copyright &y& Elsevier]

Abstract: In order to improve the detection efficiency and sensitivity for 182Hf measurement in HI-13 AMS systems at China Institute of Atomic Energy (CIAE), a new method was developed. Main features of the method include: (1) the installation of a new injection system with high mass resolution, (2) the establishment of a method based on solid-phase reaction to prepare HfF4 samples from HfO2. The experimental results show that the, mass resolution (M/ΔM) of the new injector system can reach nearly 700; the beam current of ions from HfF4 samples produced by solid-phase reaction is about two times higher than that of previous method. [Copyright &y& Elsevier]