Mesostructured zeolites: bridging the gap between zeolites and MCM-41

Surfactant-templating is one of the most versatile and useful techniques to implement mesoporous systems into solid materials. Various strategies based on various interactions between surfactants and solid precursors have been explored to produce new structures. Zeolites are invaluable as size- and shape-selective solid acid catalysts. Nevertheless, their micropores impose limitations on the mass transport of bulky feed and/or product molecules. Many studies have attempted to address this by utilizing surfactant-assisting technology to alleviate the diffusion constraints. However, most efforts have failed due to micro/mesopore phase separation. Recently, a new technique combining the uses of cationic surfactants and mild basic solutions was introduced to synthesise mesostructured zeolites. These materials sustain the unique characteristics of zeolites (i.e., strong acidity, crystallinity, microporosity, and hydrothermal stability), including tunable mesopore sizes and degrees of mesoporosity. The mesostructured zeolites are now commercially available through Rive Technology, and show superior performance in VGO cracking. This feature article provides an overview of recent explorations in the introduction of mesoporosity into zeolites using surfactant-templating techniques. Various porous materials, preparation methods, physical and catalytic properties of mesostructured zeolites will be discussed.

MOOCs, Open educational resources and social networking: bridging the gap between informal and formal learning

MOOCs and open educational resources (OER) provide a wealth of learning opportunities for people around the globe, many of whom have no access to formal higher education. OER are often difficult to locate and are accessed on their own without support from or dialogue with subject experts and peers. This paper looks at whether it is possible to develop effective learning communities around OER and whether these communities can emerge spontaneously and in a self-organised way without moderation. It examines the complex interplay between formal and informal learning, and examines whether MOOCs are the answer to providing effective interaction and dialogue for those wishing to study at university level for free on the Internet.

Terahertz Response of Excitons in Nanorod Heterostructures

Quantum-confined systems are one of the most promising ways to enable us to control a material's interactions with light. Nanorods in particular offer the right dimensions for exploring and manipulating the terahertz region of the spectrum. In this thesis, we model excitons confined inside a nanorod using the envelope function approximation. A region-matching transfer matrix method allows us to simulate excitonic states inside arbitrary heterostructures grown along the length of the rod. We apply the method to colloidal CdSe rods 70 nm in length and under 10 nm in diameter, capped with ligands of DDPA and pyridine. We extend past studies on these types of rods by taking into account their dielectric permittivity mismatch. Compared to previous calculations and experimentally measured terahertz absorption, we predict a higher energy main 1S$z$ to 2P$z$ transition peak. This indicates that the rods are likely larger in diameter than previously thought. We also investigate a nanorod with GaAs/Al$_{0.3}$Ga$_{0.7}$As coupled double dots. The excitonic transitions were found to be manipulable by varying the strength of an applied electric field. We employ quasi-static state population distributions to simulate the effects of exciton relaxation from optically active states to dim ground states. A critical value of the applied field, corresponding to the exciton binding energy of ~18 meV, was found to dramatically alter the terahertz absorption due to state mixing. Above this critical field, more nuanced shifts in transition energies were observed, and gain from radiative relaxation to the ground state is predicted.

The Governance Gap in European Security and Defence. CEPS Policy Brief No. 310, 19 December 2013

The true causes of the EU’s inertia as a security actor in its neighbourhood and beyond are not a lack of capability or even austerity measures, but the absence of a core group of states committed to driving integration forward, argues Giovanni Faleg. Member states are reluctant to set clear common strategic priorities and struggle to agree on a revision of the institutional rules. Their strategic cultures and interests differ significantly; they hold different visions of the Common Security and Defence Policy (CSDP) and are unwilling to use the CSDP instruments at their disposal.

The transatlantic growth gap. CEPS Commentary, 5 August 2014

Daniel Gros argues in this commentary that the cause of the transatlantic growth gap following the recovery starting in 2010 from the global financial crisis should not be sought in excessive eurozone austerity or the excessive prudence of the European Central Bank. Rather, compared to the US, he argues that the excess debt created in the EU during the boom years has been much more difficult to work off. He acknowledges that European officials are right to promote structural reforms of EU countries’ labour and product markets, but advises that they should also focus on overhauling and accelerating bankruptcy procedures, so that losses can be recognised more quickly and over-indebted households can start afresh, rather than being shackled for years.

Closing the gap? Military co-operation from the Baltic Sea to the Black Sea. OSW Report, December 2012

The contracting defence budgets in Europe, the difficulties in developing the EU’s security policy, NATO's transformation, the reorientation of US security policy and the problems experienced by European defence industries – all together have in recent years created an increased interest in political, military and military-technological co-operation in Europe.It has manifested itself in concepts of closer co-operation within NATO and the EU (smart defence and pooling&sharing), bilateral and multilateral initiatives outside the structures of NATO and the EU (such as the Nordic Defence Co-operation or the Franco-British co-operation) and debates about the prerequisites, principles and objectives of bilateral, multilateral and regional security and defence co-operation. The present report aims to analyse the potential for security and defence co-operation among selected countries in the area between the Baltic Sea and the Black Sea, i.e. the Nordic states (Denmark, Finland, Norway and Sweden), the Baltic states (Lithuania Latvia and Estonia), Poland's partners in the Visegrad Group (the Czech Republic, Hungary and Slovakia) as well as Romania and Bulgaria. The authors were guided by the assumption that those states are Poland's natural partners for closer regional military co-operation. It may complement ‘the Western’ direction of Poland's security and defence policy, i.e. relations with the partners from the Weimar Triangle and the US. Its goal is not to replace the existing security structures but rather to strengthen military capabilities in the region within NATO and the EU.

Filling the gap: open economy considerations for more reliable potential output estimates. Bruegel Working Paper 2015/11, October 2015

This paper argues that the Phillips curve relationship is not sufficient to trace back the output gap, because the effect of excess demand is not symmetric across tradeable and non-tradeable sectors. In the non-tradeable sector, excess demand creates excess employment and inflation via the Phillips curve, while in the tradeable sector much of the excess demand is absorbed by the trade balance. We set up an unobserved-components model including both a Phillips curve and a current account equation to estimate ‘sustainable output’ for 45 countries. Our estimates for many countries differ substantially from the potential output estimates of the European Commission, IMF and OECD. We assemble a comprehensive real-time dataset to estimate our model on data which was available in each year from 2004-15. Our model was able to identify correctly the sign of pre-crisis output gaps using real time data for countries such as the United States, Spain and Ireland, in contrast to the estimates of the three institutions, which estimated negative output gaps real-time, while their current estimates for the pre-crisis period suggest positive gaps. In the past five years the annual output gap estimate revisions of our model, the European Commission, IMF, OECD and the Hodrick-Prescott filter were broadly similar in the range of 0.5-1.0 percent of GDP for advanced countries. Such large revisions are worrisome, because the European fiscal framework can translate the imprecision in output gap estimates into poorly grounded fiscal policymaking in the EU.

Evaluation of the usability and benefits of twist wire GMAW and FACW narrow gap welding /

"March 1988."

Strategic target planning : bridging the gap between theory and practice /

Mode of access: Internet.

Dredging alternatives study, Cubits Gap, Lower Mississippi River.

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Dredging alternatives study Cubits Gap, Lower Mississippi River.

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Study of furnishings alternatives : Slateford Farm, Delaware Water Gap National Recreation Area, Pennsylvania /

"NPS D-68"--P. [3] of cover.

Tocks Island Lake development : a comprehensive evaluation of environmental quality : Delaware River Basin Tocks Island Lake, Pennsylvania, New York, Delaware Water Gap ... Kittatinny Mountain Project ... /

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San Luis Valley Project: Wagon Wheel Gap reservoir, Platoro reservoir, Magote reservoir, Closed Basin drain.

Reproduced from typewritten copy.