scholarly journals Ethnic leadership and Midwestern politics: Scandinavian Americans and the Progressive Movement in Wisconsin, 1890-1914

2005 ◽  
Vol 43 (01) ◽  
pp. 43-0511-43-0511
1949 ◽  
Vol 14 (1) ◽  
pp. 181
Author(s):  
Odin W. Anderson ◽  
Kenneth Campbell MacKay
Keyword(s):  

Materials ◽  
2021 ◽  
Vol 14 (10) ◽  
pp. 2609
Author(s):  
Abniel Machín ◽  
Kenneth Fontánez ◽  
Juan C. Arango ◽  
Dayna Ortiz ◽  
Jimmy De León ◽  
...  

At present, the world is at the peak of production of traditional fossil fuels. Much of the resources that humanity has been consuming (oil, coal, and natural gas) are coming to an end. The human being faces a future that must necessarily go through a paradigm shift, which includes a progressive movement towards increasingly less polluting and energetically viable resources. In this sense, nanotechnology has a transcendental role in this change. For decades, new materials capable of being used in energy processes have been synthesized, which undoubtedly will be the cornerstone of the future development of the planet. In this review, we report on the current progress in the synthesis and use of one-dimensional (1D) nanostructured materials (specifically nanowires, nanofibers, nanotubes, and nanorods), with compositions based on oxides, nitrides, or metals, for applications related to energy. Due to its extraordinary surface–volume relationship, tunable thermal and transport properties, and its high surface area, these 1D nanostructures have become fundamental elements for the development of energy processes. The most relevant 1D nanomaterials, their different synthesis procedures, and useful methods for assembling 1D nanostructures in functional devices will be presented. Applications in relevant topics such as optoelectronic and photochemical devices, hydrogen production, or energy storage, among others, will be discussed. The present review concludes with a forecast on the directions towards which future research could be directed on this class of nanostructured materials.


2021 ◽  
Vol 69 (3) ◽  
pp. 702-724
Author(s):  
Jean-Pierre Poulain

Among the different theories used to explain social change, the transition theory holds a special place. It has been applied to subjects such as demography, epidemiology, nutrition, etc. and most often from a multidisciplinary perspective. However, beyond the apparent uniqueness of the transition label there are quite different theoretical frameworks and presuppositions, which can be a source of misunderstanding. A first perspective considers change as the transition from one stable state to another and concentrates on the processes at work in the transition phase. It focuses attention on the interactions between cultural and biological variables and tries to take into account the consequences of the fact that they move at different rates. A second perspective conceives change as a series of stages (more or less stable situations) and proceeds to analyse the structural transformation of the organisation at each stage. The emphasis is placed on the transformations that take place during these stages. This brings us closer to the theory of stages. Finally, a third perspective combines stages and transitions. Change is seen as part of an evolutionary and progressive movement and as being reversible or not. This article studies the cognitive organisation of the different theoretical variants of the transition model in which food plays a more or less important role.


1963 ◽  
Vol 15 (3) ◽  
pp. 473
Author(s):  
Bartlett C. Jones ◽  
James H. Timberlake
Keyword(s):  

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