Structural transformations in poly(di-n-alkylsiloxane)s with alkyl side groups containing 7 to 10 carbon atoms

Temperature dependent X-ray diffraction studies of poly(di-n-alkylsiloxane)s substituted with side chains containing 7 to 10 carbon atoms have been carried out in order to elucidate the crystalline structure of these materials. In contrast to their lower substituted homologues, no evidence for the presence of a hexagonal columnar mesophase could be found for the investigated materials. At low temperatures, far below the melting temperature, the polysiloxane backbones are assumed to pack in an orthorhombic lattice, with the n-alkyl side chains in a planar all-trans conformation and oriented perpendicularly to the backbone. The paraffinic n-alkyl side chains were found to crystallize in an orthorhombic lattice. The thermal behaviour of the investigated materials has been observed to show an odd-even effect. Whereas poly(di-n-heptylsiloxane) and poly(di-n-nonylsiloxane) were found to melt in a single step, an intermediate state of order was observed for poly(di-n-octylsiloxane) and poly(di-n-decylsiloxane) upon heating from the crystalline to the isotropic state. For this intermediate state, a pseudohexagonal packing of the n-alkyl side chains is proposed

Carbon emissions pinch analysis (CEPA) for emissions reduction in the New Zealand electricity sector

Carbon Emissions Pinch Analysis (CEPA) is a recent extension of traditional thermal and mass pinch analysis to the area of emissions targeting and planning on a macroscale (i.e. economy wide). This paper presents a carbon pinch analysis of the New Zealand electricity industry and illustrates some of the issues with realising meaningful emissions reductions. The current large proportion of renewable generation sources (~67% in 2007) complicates wholesale emissions reductions. The biggest growth in renewable generation is expected to come from geothermal energy followed by wind and hydro. A four fold increase in geothermal generation capacity is needed in addition to large amounts of new wind generation to reduce emissions to around 1990 levels and also meet projected demand. The expected expansion of geothermal generation in New Zealand raises issues of GHG emissions from the geothermal fields. The emissions factors between fields can vary by almost two orders of magnitude making predictions of total emissions highly site specific

Hydrosilylation of 1-alkenes with dichlorosilane

Symmetrically and unsymmetrically substituted diorganodichlorosilanes have been prepared by hydrosilylation with dichlorosilane using two different platinum catalysts, i.e., hexachloroplatinic acid (Speier's catalyst) and a platinum cyclovinylmethylsiloxane complex. Hydrosilylation of unsubstituted 1-alkenes proved to be very efficient, yielding anti-Markonikov substituted di-n-alkyldichlorosilanes. However, no reaction was observed when electron-deficient 1-alkenes were used. Octacarbonyldicobalt enabled formation of the monoadduct of 1H,1H,2H-perfluoro-1-hexene with dichlorosilane, which was employed in a second hydrosilylation of the olefin. Thus, the anti-Markovnikov diadduct was obtained in 40% overall yield. The two-step synthesis has also been applied successfully to obtain unsymmetrically substituted diorganodichlorosilanes containing nitrile and ether groups

Strategic innovation networks

This thesis draws on two key areas of the innovation literature, the strategic management of technology (SMOT) and innovation networks. The aim is to integrate these two areas of the management of innovation literature to develop a framework which I describe as the Strategic Innovation Network (SIN). The key proposition that the revised framework (SIN) aims to address is based on the work of Chandler (1962). Chandler's (1962) conclusion that 'structure follows strategy' is examined in relation to the interaction between corporate/technology strategy and network structure. The SIN is intended to address weaknesses in both the SMOT and network literature. The research data is based on five detailed longitudinal case studies. The organisations are defined as mid-corporate firms operating in traditional manufacturing sectors. Each organisation was chosen on the basis that it was aiming to develop its innovative capacity through product or process innovation projects. The research was carried out over an 18 month period with interviews being held regularly to develop the longitudinal aspect of the study analysis. The data for each individual case study is examined using the SIN framework. The longitudinal approach addresses the objective to provide a dynamic model of the innovation processes by mapping the changes in network structure during the course of individual projects. The network structural changes are examined in relation to each organisation's strategy and five key dynamic network stages are identified in relation to the innovation process. These network stages show the influence strategy has on the structures adopted by the five case studies

Finanzmarktintegration und Wirtschaftsentwicklung im Kontext der EU-Osterweiterung

Mit den EU-Osterweiterungen vom 1. Mai 2004 und vom 1. Januar 2007 hat die Europäische Union sich enorm vergrößert; zugleich ist mit der Aufnahme Sloweniens ein erstes osteuropäisches Beitrittsland Mitglied der Eurozone geworden. Da Finanzmärkte für die Allokation der Ersparnisse und die Risikobepreisung bzw. die Investitions- und Innovationsfinanzierung eine zentrale Rolle spielen, kommt mit Blick auf in EU-Beitrittsländern gewünschte Aufholprozesse den Fragen der Finanzmarktintegration große Bedeutung zu. In den relativ armen Beitrittsländern herrscht die Erwartung, dass einerseits die ordnungspolitische Neuorientierung und andererseits die Mitgliedschaft in der EU positiv zum ökonomischen Aufholprozess beiträgt; zahlreiche Länder Osteuropas haben bei der außen- und binnenwirtschaftlichen Modernisierung bzw. Anpassung binnen 15 Jahren erhebliche Fortschritte erzielt. Die Analyse skizziert zunächst den Prozess der monetären Integration in der EU und präsentiert ausgewählte Daten zu den Finanzmärkten osteuropäischer Länder, ehe danach die theoretische Analyse zur Verbindung von Finanzmarktintegration und Wirtschaftsentwicklung präsentiert wird – unter Einbeziehung neuerer empirischer Ergebnisse. Der Schlussabschnitt formuliert Konsequenzen für die Wirtschaftspolitik.Financial Markets, Economic Growth, EU Integration

Minimising carbon emissions and energy expended for the New Zealand transport sector through to 2050

Carbon Emissions Pinch Analysis (CEPA) and Energy Return on Energy Investment (EROI) analysis are combined to investigate the feasibility of New Zealand (NZ) reaching a 1990 emission levels for transport in 2050. The transportation sector traditionally has been a difficult area to transition to high levels of renewable energy because of the strong dependency on fossil fuels. Multiple scenarios for reducing transport emissions are analysed. With NZ’s unique mix of renewable energy resources the analysis demonstrates that NZ is in a very good position to sustainably meet their future transport needs provided substantial commitment is made to transition light vehicle fleet to hybrid vehicles, plug-in hybrids vehicles and electric vehicles by 2050. Electrification of rail within and between major centres will also require major political commitment. The resulting increase in electricity demand for transport is 3.6 TWh (or 4.8 % of electricity generation in NZ). We show the minimum amount of biofuel renewable production to achieve the goal of 1990 emissions level in 2050 is 46 PJ. Delivering 46 PJ is expected to be well within the potential biofuel production capacity of NZ. The delivery of economically competitive renewable liquid biofuels will also require close cooperation and system integration with other energy systems like the electricity sector and industrial process heat sector

Late Archean crust-​mantle interactions: geochemistry of LREE-​enriched mantle derived magmas. Example of the Closepet batholith, southern India

The Closepet batholith in South India is generally considered as a typical crustal granite emplaced 2.5 Gyr ago and derived through partial melting of the surrounding Peninsular Gneisses (3.3-​3.0 Gyr)​. In the field, it appears as a composite batholith made up of at least two groups of intrusions. An early SiO2-​poor group (clinopyroxene quartz-​monzonite and porphyritic monzogranite) is located in the central part of the batholith. These rocks display a narrow range in both initial 87Sr​/86Sr ratio (Sri, 0.7017-​0.7035) and εNd (-​0.9 to -​4.1)​. A later SiO2-​rich group (equigranular gray and pink granites) is located along the interface between the SiO2-​poor group and the Peninsular Gneisses. They progressively grade into migmatized Peninsular Gneisses, thus indicating their anatectic derivation. Their isotopic characteristics vary over a wide range (Sri = 0.7028-​0.7336 and εNd values from -​2.7 to -​8.3, at 2.52 Gyr)​. Field and geochronol. evidence shows that the two groups are broadly contemporaneous (2.518-​2.513 Gyr) and mech. mixed. This observation is supported by the chem. data that display well defined mixing trends in the εSr vs εNd and elemental variation diagrams. The continuous chem. variation of the two magmatic bodies is interpreted in terms of interaction and mixing of two unrelated end-​members derived from different source regions (enriched peridotitic mantle and Peninsular Gneisses)​. It is proposed that the intrusion of mantle-​derived magmas into mid-​crustal levels occurred along a transcurrent shear zone; these magmas supplied addnl. heat and fluids that initiated anatexis of the surrounding crust. During this event, large-​scale mixing occurred between mantle and crustal melts, thus generating the composite Closepet batholith. The mantle-​derived magmatism is clearly assocd. with granulite-​facies metamorphism 2.51 ± 0.01 Gyr ago. Both are interpreted as resulting from a major crustal accretion event, possibly related to mantle plume activity

Navier-Stokes transport coefficients of dd-dimensional granular binary mixtures at low density

The Navier-Stokes transport coefficients for binary mixtures of smooth inelastic hard disks or spheres under gravity are determined from the Boltzmann kinetic theory by application of the Chapman-Enskog method for states near the local homogeneous cooling state. It is shown that the Navier-Stokes transport coefficients are not affected by the presence of gravity. As in the elastic case, the transport coefficients of the mixture verify a set of coupled linear integral equations that are approximately solved by using the leading terms in a Sonine polynomial expansion. The results reported here extend previous calculations [V. Garz\'o and J. W. Dufty, Phys. Fluids {\bf 14}, 1476 (2002)] to an arbitrary number of dimensions. To check the accuracy of the Chapman-Enskog results, the inelastic Boltzmann equation is also numerically solved by means of the direct simulation Monte Carlo method to evaluate the diffusion and shear viscosity coefficients for hard disks. The comparison shows a good agreement over a wide range of values of the coefficients of restitution and the parameters of the mixture (masses and sizes).Comment: 6 figures, to be published in J. Stat. Phy