Neutral AuCl complexes supported in linear high molecular weight, poly-spirophosphazene-phosphine copolymers and its conversion to nanostructured gold materials

Summary The reaction under very mild conditions of the polyspirophosphazene copolymer with pendant diphenylphosphine groups {[NP(O₂C₁₂H₈)]_0.85[NP(OC₆H₄PPh₂)₂]_0.15}_n (I) (O₂C₁₂H₈= 2,2’-dioxybiphenyl) with [Au(THT)Cl] (THT = tetrahydrothiophene) gives the neutral polymeric complex {[NP(O₂C₁₂H₈)]_0.85[NP(OC₆H₄PPh₂-AuCl)₂]_0.15}_n (II). The new material has been characterized by spectrocopic and thermochemical methods (TGA and DSC). Pyrolysis of the Au polymer (I) in air at 800 °C gave gold nanostructured materials that were characterized by TEM, SEM-EDAX and X-ray diffraction. Nanoparticles in the range of 90 to 130 nm were seen. Dedicated to Professor Victor Riera, Departamento de Quimica Orgánica e Inorgánica, Universidad de Oviedo, Spain, on the occasion of his 70^thbirthday.     

Electrical,Thermal, and Mechanical Characterization of Poly(propylene)/Carbon Nanotube/Clay Hybrid Composite Materials

A set of hybrid composite materials based on a PP matrix with multiwalled CNTs and clay particles is prepared and characterized. The incorporation of clay particles into a percolated composite with 3 wt% CNT disrupts the percolation, decreasing dramatically the electrical conductivity. As expected for layered fillers, PP/CNT/clay hybrid composite materials and PP/clay composites display increases as high as 100 °C in the temperature for the maximum rate of weight loss. Surprisingly, these temperatures are just slightly higher than those of PP/CNT composites. PP/CNT composites display viscosities that are considerably lower than those of PP/clay composites. A synergistic effect of both fillers is observed in the viscoelastic response of PP/CNT/clay materials.

     

A high resolution and large solid angle x-ray Raman spectroscopy end-station at the Stanford Synchrotron Radiation Lightsource

We present a new x-ray Raman spectroscopy end-station recently developed, installed, and operated at the Stanford Synchrotron Radiation Lightsource. The end-station is located at wiggler beamline 6-2 equipped with two monochromators-Si(111) and Si(311) as well as collimating and focusing optics. It consists of two multi-crystal Johann type spectrometers arranged on intersecting Rowland circles of 1 m diameter. The first one, positioned at the forward scattering angles (low-q), consists of 40 spherically bent and diced Si(110) crystals with 100 mm diameters providing about 1.9% of 4π sr solid angle of detection. When operated in the (440) order in combination with the Si (311) monochromator, an overall energy resolution of 270 meV is obtained at 6462.20 eV. The second spectrometer, consisting of 14 spherically bent Si(110) crystal analyzers (not diced), is positioned at the backward scattering angles (high-q) enabling the study of non-dipole transitions. The solid angle of this spectrometer is about 0.9% of 4π sr, with a combined energy resolution of 600 meV using the Si (311) monochromator. These features exceed the specifications of currently existing relevant instrumentation, opening new opportunities for the routine application of this photon-in/photon-out hard x-ray technique to emerging research in multidisciplinary scientific fields, such as energy-related sciences, material sciences, physical chemistry, etc.     

Teaching and learning strategies and evaluation changes for the adaptation of the Chemical Engineering degree to EHES

An integrated learning methodology has been developed and implemented in order to adapt the Chemical Engineering degree in the University of Valladolid (Spain) to the European Higher Education Space (EHES) philosophy. It was necessary to modify the objectives and theoretical contents of the different subjects and also the learning methodology, considering the general chemical engineering skills and also the transferable skills reached by the students, according to the recommendations of the European Federation of Chemical Engineering (EFCE) for chemical engineering education in Bologna two-cycle degree system.

This methodology has been applied to the seventh semester of a 5 years Chemical Engineering degree. The main objectives of the proposed strategy were:

• To provide to the student with a holistic, integrated and applied vision of the different subjects involved in chemical engineering, coordinating all of them and planning common activities as a case study based on an industrial process.

• To help students to develop transferable skills by means of designing suitable teaching and learning strategies.

• To prepare the students for the long-life learning.

General and particular objectives were defined adapting the course to the EHES philosophy. In this sense, the programmes in terms of the learning outcomes and competences to be acquired were designed, the total student workload to get the objectives of the programme was estimated and the entire course was programmed and planned in a detailed schedule. A course guide was elaborated including all this information, resulting in a useful instrument for teachers and students.

This methodology was complemented with the evaluation of the global learning process. The evaluation made was based on the next two aspects:

• Student learning evaluation. Tutorial sessions, written reports, oral presentations, discussion sessions and partial and final written exams were considered.

• Learning methodology evaluation. External evaluation requires carrying out inquiries, both to students and teachers involved.

Overpotential deposition of copper on an iodine-modified Au(1 1 1) electrode

Cyclic voltammetry, chronoamperometry and in situ electrochemical scanning tunneling microscopy were used to study the kinetics of nucleation and crystal growth during the initial stages of copper overpotential deposition (OPD) on a previously iodine-modified Au(1 1 1) electrode, from an aqueous solution 10⁻³ M CuSO₄ in 0.05 M H₂SO₄. The starting potential during step experiments was chosen in the region where the gold electrode was completely free of the copper deposit. The recorded current transients for copper deposition onto the iodine-modified Au(1 1 1) electrode surface appear to be very complex, with the unusual presence of two or more current maxima. A new method was used for quantitative evaluation of current transients that involves the transition UPD-OPD, developed by our group [M. Palomar-Pardavé, I. González, N. Batina, J. Phys. Chem. B 104 (2000) 3545], was used for the quantitative interpretation. Our results show that, within a single current transient, copper adsorption and two types of nucleation process: two-dimensional (2D) and three-dimensional (3D) limited by lattice incorporation of copper adatoms and diffusion of Cu(II) ion, respectively, take place simultaneously. STM images revealed the enhanced growth of 3D copper on edge of I-Au(1 1 1) during the early stages of deposition. Moreover, our results strongly suggest that the iodine adlayer is constantly present, even after the striping Cu that was overpotential deposited.     

Bilinear Models for Spatio-Temporal Point Distribution Analysis

In this work we describe the usage of bilinear statistical models as a means of factoring the shape variability into two components attributed to inter-subject variation and to the intrinsic dynamics of the human heart. We show that it is feasible to reconstruct the shape of the heart at discrete points in the cardiac cycle. Provided we are given a small number of shape instances representing the same heart at different points in the same cycle, we can use the bilinear model to establish this. Using a temporal and a spatial alignment step in the preprocessing of the shapes, around half of the reconstruction errors were on the order of the axial image resolution of 2 mm, and over 90% was within 3.5 mm. From this, we conclude that the dynamics were indeed separated from the inter-subject variability in our dataset.     

Eventizing applications in an adaptive middleware platform

An architecture supporting dynamic aspect-oriented programming establishes an event infrastructure for to extend existing application's behavior at runtime. The adaptive middleware platform described to support the eventizing applications with extensions that are added at runtime in response to new requirements or necessary adaptations. We are currently completing its implementation and exploring more advanced forms of adaptation, including dynamic changes to the event management system itself. Furthermore, the implementation is still too heavy to run on resource-constrained devices like iPAQs, so we plan to take advantage of lighter virtual machines.     

材料选择的试验生活

来自英国皇家艺术学院产品设计系的Tomas Alonso在到英国研究学习之前，在美国的OZ RACING公司担任4年的设计总监，然后于2002年成立了自己的设计工作公司。TOMAS的设计研究一直非常注重材料和功能的重新定义；     

Widespread hemodynamic depression and focal platelet accumulation after fluid percussion brain injury: a double-label autoradiographic study in rats

In Kenya indoor and outdoor resting densities of Anopheles arabiensis and Anopheles funestus at the Ahero rice irrigation scheme, and Anopheles gambiae s.s., An. arabiensis and An. funestus at the Miwani sugar belt were assessed for 13 months by pyrethrum spray collections in houses and granaries. The vector's house leaving behaviour was evaluated with exit traps and it was noted that early exophily (i.e., deliberate) was not detected in any of the vectors. Assortative indoor/outdoor resting behaviour was studied by a capture-mark-release-recapture method and showed that in An. arabiensis both indoor and outdoor resting traits were present in the same individuals. Samples of half-gravid female An. gambiae s.l. were chromosomally identified either as Anopheles gambiae s.s. or An. arabiensis and in a subsample chromosomal inversions were read. Anopheles gambiae s.s. and An. arabiensis had the 2Rb inversion but in addition the 2La inversion was found in An. gambiae s.s. and this is an indication of low chromosomal variation. At Ahero An. arabiensis was most abundant when the rice crop was immature and An. funestus when the crop was mature. This succession of vectors facilitated the transmission of malaria throughout the year. At Miwani, An. gambiae s.l. population peaked during the long rains but the proportion of An. arabiensis was highest during the dry season. The indoor resting density of males of the three vector species was less than half of the females.