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The transition probabilities of Kα hypersatellite lines and energy shifts with respect to the corresponding diagram lines are computed using the Dirac–Fock model for several values of atomic number Z throughout the periodic table. The influence of the Breit interaction on the Kα₁^h/Kα₂^h line intensity ratio, Kα₁^h and Kα₂^h line energy shifts and Kα₁^h to Kα₂^h line energy splitting is evaluated. Double-K shell hole threshold values for selected elements with 23 ⩽Z⩽ 30, calculated within the same approach, are compared with available experimental results.

The transition probabilities of K&alpha; hypersatellite lines and energy shifts with respect to the corresponding diagram lines are computed using the Dirac&ndash;Fock model for several values of atomic number <I>Z</I> throughout the periodic table. The influence of the Breit interaction on the K&alpha;<SUB>1</SUB><SUP>h</SUP>/K&alpha;<SUB>2</SUB><SUP>h</SUP> line intensity ratio, K&alpha;<SUB>1</SUB><SUP>h</SUP> and K&alpha;<SUB>2</SUB><SUP>h</SUP> line energy shifts and K&alpha;<SUB>1</SUB><SUP>h</SUP> to K&alpha;<SUB>2</SUB><SUP>h</SUP> line energy splitting is evaluated. Double-K shell hole threshold values for selected elements with 23 &les;<I>Z</I>&les; 30, calculated within the same approach, are compared with available experimental results.

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The emergence of multi-core processors is promoting the use of concurrency and multithreading. To raise the abstraction level of synchronization constructs is fundamental to ease the development of concurrent software, and Software Transactional Memory (STM) is a good approach towards such goal. However, execution environment issues such as the processor instruction set, caching policy, and memory model, may have strong influence upon the reliability of STM engines. This paper addresses the testing of STM engines aiming at improving their reliability and independence from execution environment. From our experience with porting and extending a specific STM engine, we report on some of the bugs found and synthesize some testing patterns that proved to be useful at testing STM engines.

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A requirement of many surface science studies is the capability to alter a sample temperature in a controlled mode. Sample preparation procedures such as heating or cooling ramps, high temperature spikes, fast annealing, or simply maintaining a sample at a very high, or very low, temperature are common. To address these issues, we describe the design and the construction of a multipurpose sample holder. Key points of this design are operation in an extended temperature range from liquid nitrogen (LN(2)) temperature to approximately 1300 K, temperature control during heating and cooling, low thermal inertia with rates up to 50 K s(-1) (heating) and -20 K s(-1) (cooling), and small heated volume to minimize background problems in thermal desorption spectroscopy (TDS) spectra. With this design the sample can be flash heated from LN(2) temperature to 1300 K and cooled down again in less than 100 s. This sample holder was mounted and tested in a multitechnique apparatus and adds a large number of sample preparation procedures as well as TDS to the list of already available surface analysis techniques.

To achieve highly accurate controlled depositions a specially designed vapour source, for metals with low to medium melting temperature, was developed. A quartz crystal microbalance is fitted inside the evaporation chamber to provide real-time rate and thickness monitoring. A carefully planned geometry allows maintaining a small deposition area centred on the sample without compromising flow rate measurements. Dosing rates as low as 0.02 ML/min are easily achieved, therefore providing true sub-monolayer control. This source was tested and calibrated for Ag and is being successfully used to study the growth of Ag clusters on TiO2.

We report the 98% assignment of the apo-form of an orange protein, containing a novel Mo-Cu cluster isolated from Desulfovibrio gigas. This protein presents a region where backbone amide protons exchange fast with bulk solvent becoming undetectable. These residues were assigned using C-13-detection experiments.

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Carbon dioxide solubility in a natural biodegradable polymer, namely poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) and the diffusion coefficients are reported. Equilibrium solubility of dense carbon dioxide in PHBV was studied by a gravimetric method in a temperature range from 308 to 313 K and a pressure range from 10.0 to 15.0 MPa. The copolymer presented Fickian behavior and Fick's diffusion model was applied to determine the amount of carbon dioxide present in the samples after a predermined exposure time as well as the diffusion coefficients. Diffusion coefficients for the sorption under supercritical (sc) conditions and desorption at ambient conditions were determined and compared. To evaluate the influence of the HV content in the amount of maximum sorption degree of the polymer, different samples of PHBV copolymers were tested and the sorption curves are here presented. © 2006 Elsevier B.V. All rights reserved.

The micronization of poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) from organic solutions using supercritical antisolvent (SAS) technique has been successfully achieved. SAS experiments were carried out at different operational conditions and microspheres with mean diameters ranging from 3 to 9 $μ$m were obtained. The effect of CO2 and liquid flow, temperature and pressure on particle size and particle size distribution was evaluated. The microspheres were precipitated from a dichloromethane (DCM) solution. The best process conditions for this mixture were, according to our study, 40 °C, 100 bar, 1 mL min-1 liquid flow and 10 L min-1 carbon dioxide flow. Experiments with polymers containing different HV percentages were carried out. The powders obtained became more spherical as the HV content decreased. © 2006 Elsevier B.V. All rights reserved.

Supercritical fluid impregnation was tested to prepare a new ophthalmic drug delivery device. Poly(methylmethacrylate-co-ethylhexylacrylate-co-ethyleneglycoldimethacr ylate), P(MMA-EHA-EGDMA) has been proposed by Mariz [M. Mariz, Preparação de uma lente intra-ocular dotada de um sistema de libertação controlada de fármaco, Master Thesis, Universidade de Coimbra, 1999] as a promising matrix to be used for intraocular delivery of anti-inflammatory drugs used in eye surgery. This matrix was successfully impregnated with flurbiprofen, a non-steroidal anti-inflammatory agent. The success of the impregnation was evaluated by scanning electron microscopy (SEM) analysis and also by in vitro drug release studies. The effect of some operating parameters was evaluated, namely, pressure and contact time. The operating pressure will influence both the solubility of the drug in the supercritical fluid but also the sorption degree of the polymeric matrix in the presence of carbon dioxide. The solubility of the drug in carbon dioxide and the sorption degree are reported in previous studies. A comparison between the batch and the semi-continuous impregnation process is also presented. The supercritical fluid impregnation proved to be feasible for the preparation of a new ophthalmic drug delivery system. The drug release profiles suggest that the drug can be released up to three months, which is a major advantage for the prevention of the inflammatory response after ophthalmic surgery. © 2007 Elsevier B.V. All rights reserved.

{We prove the existence of weak solutions for the forward and backward statistical transport equations associated with the 2D Euler equations. Such solutions can be interpreted, respectively, as a statistical Lagrangian and a statistical Eulerian description of the motion of the fluid.}

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