1,581 research outputs found

    EXAFS study of nickel exchanged into zeolite Y

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    EXAFS and near edge spectroscopy were used to monitor changes i n Ni coordination as a function of treatment conditions after aqueous exchange into zeolite Y. Our results suggest that after calcination and dehydration under the conditions of this study, major site occupancy for Ni appears to be in the tri-coordinate exchange sites , and not i n the hexagonal prisms as suggested by previous x-ray diffraction results

    International Trade As An Engine of Economic Growth Revisited: A Case of Egypt

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    The promotion of free trade is one of the oldest policy implications offered by international economic theory. While significant disconnects have historically existed between the politics and the economics of trade policy, the rapid economic growth experienced by the export-oriented Asian countries during the 1960s and 1970s amidst a largely stagnating and trade-restrictive developing world provided a precedent for effective development policy, especially within the world’s less developed countries (LDCs). Free trade arguments have since been championed by a majority of global institutions, including the International Monetary Fund (IMF hereafter), the International Bank for Reconstruction and Development (IBRD) or World Bank, the Organization for Economic Co-operation and Development (OECD hereafter), and the World Trade Organization (WTO hereafter). The argument goes that a reduction in trade barriers will induce greater economic efficiency within LDCs by offering cheaper world prices to domestic consumers (increasing consumer welfare) while creating conditions of competition for domestic producers (forcing domestic production to shift towards the most efficient sectors based upon availability of domestic factors)

    De-aliasing Undersampled Volume Images for Visualization

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    We present and illustrate a new technique, Image Correlation Supersampling (ICS), for resampling volume data that are undersampled in one dimension. The resulting data satisfies the sampling theorem, and, therefore, many visualization algorithms that assume the theorem is satisfied can be applied to the data. Without the supersampling the visualization algorithms create artifacts due to aliasing. The assumptions made in developing the algorithm are often satisfied by data that is undersampled temporally. Through this supersampling we can completely characterize phenomena with measurements at a coarser temporal sampling rate than would otherwise be necessary. This can save acquisition time and storage space, permit the study of faster phenomena, and allow their study without introducing aliasing artifacts. The resampling technique relies on a priori knowledge of the measured phenomenon, and applies, in particular, to scalar concentration measurements of fluid flow. Because of the characteristics of fluid flow, an image deformation that takes each slice image to the next can be used to calculate intermediate slice images at arbitrarily fine spacing. We determine the deformation with an automatic, multi-resolution algorithm

    EXAFS study of nickel tetracarbonyl and nickel clusters in zeolite Y

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    Adsorption and thermal decomposition of Ni(CO)4 in the cage system of zeolite Y have been studied with EXAFS, electron microscopy and IR spectroscopy , Ni(CO)4 is adsorbed as an intact molecule in both cation - free zeolite Y and NaY. Symmetry changes of the molecule in NaY are assigned to the formation of Na—OC-IMi bridges. Thermal treatment of the Ni(CO)4/NaY adduct leads to loss of CO concomitant with the formation of a binodal Ni phase. A major part of the forms clusters with diameter between 0.5 and about 1.5 nm, in addition to larger crystallites (5-30 nm), sticking at the outer surface of the zeolite matrix., The Ni-Ni scattering amplitude indicates increasing average particle size with increasing temperature

    The Nature and Purpose of Work and Productivity

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    The authors discuss the importance of the work-rest cycle for daily living

    Urban Planning as an Extension of War Planning:

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    War-city relationships had long been studied by scholars regarding wars\u27 sudden impact on cities. Studies typically focused on one specific event\u27s impact on urban military, politics, economy, or society. This approach, however, treated war\u27s impact on cities as only temporary, hindered opportunities to reveal multiple political regimes\u27 spatial competition through war-oriented city planning and construction, which is crucial for city development, and their resultant urban form changes through time. In response, this study has examined city planning and construction activities during the short time gaps between multiple military conflicts, with various military objectives, and conducted by different political regimes in Shenyang, China. In accordance with archival research, a space syntax axis analysis has been used to quantify spatial dynamics throughout war-peace-war cycles to explore the impact of military-oriented planning on city-scaled development. We have found these planning strategies, initiated by specific military goals, acted as extensions of war planning, segregating the city and causing urban fragmentation. They also acted as a driving factor which promoted modernization of the city in the early 20th century. We conclude that wars oriented planning can alter a city\u27s development track and impact its structure and form through the creation of internally connected but isolated urban districts
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