Direct electrodeposition of aluminium nano-rods

Electrodeposition of aluminium within an alumina nano-structured template, for use as high surface area current collectors in Li-ion microbatteries, was investigated. The aluminium electrodeposition was carried out in the ionic liquid 1-ethyl-3-methylimidazolium chloride:aluminium chloride (1:2 ratio). First the aluminium electrodeposition process was confirmed by combined cyclic voltammetry and electrochemical quartz crystal microbalance measurements. Then, aluminium was electrodeposited under pulsed-potential conditions within ordered alumina membranes. A careful removal of the alumina template unveiled free standing arrays of aluminium nano-rods. The nano-columns shape and dimensions are directly related to the template dimensions. To our knowledge, this is the first time that direct electrodeposition of aluminium nano-pillars onto an aluminium substrate is reported

Explanatory power of internationalization theories : a case study of Norwegian SMEs targeting developing countries

Theories on the internationalization process of firms have been developed by researchers over many decades. These theories have been affected by the present time, their origins, and the given firms in the research. Physical distance is no longer an issue, and internationalization is these days almost a necessity for a specialized SME when its domestic market is threaten by global competition. Today, more firms internationalize and they do it more rapidly than before. Influenced by authorities or their networks, going abroad has become easier. Therefore, the research problem we express is: “The problem is that, given globalization, the theories available to explain the internationalization process by SMEs are hardly applicable today.‖ Access to energy is a driver of development and plays a central role in both fighting poverty and addressing climate change. The United Nations (UN) and several other organizations are offering significant funds for carry out renewable energy (RE) projects in the developing world. These developing countries represent a huge emerging market that is an attractive target for foreign international firms. But it is also a risky market given instable regimes and an absence of regulations and institutions that constitute barriers for foreign investors. Both firms in this study offer PV technology, and their main market is in Europe. Both firms also have experience targeting developing countries. The result of the study shows that the explanatory power of the theories presented here need modification to be valid in times when the circumstances of firms change constantly and significantly

Electronic changes in poly(3,4-ethylenedioxythiophene)-coated LiFeSO4F during electrochemical lithium extraction

The redox activity of tavorite LiFeSO4F coated with poly (3,4-ethylenedioxythiophene), i.e. PEDOT, is investigated by means of several spectroscopic techniques. The electronic changes and iron-ligand redox features of this LiFeSO4F-PEDOT composite are probed upon delithiation through X-ray absorption spectroscopy. The PEDOT coating, which is necessary here to obtain enough electrical conductivity for the electrochemical reactions of LiFeSO4F to occur, is electrochemically stable within the voltage window employed for cell cycling. Although the electronic configuration of PEDOT shows also some changes in correspondence of its reduced and oxidized forms after electrochemical conditioning in Li half-cells, its p-type doping is fully retained between 2.7 and 4.1 V with respect to Li+/Li during the first few cycles. An increased iron-ligand interaction is observed in LixFeSO4F during electrochemical lithium extraction, which appears to be a general trend for polyanionic insertion compounds. This finding is crucial for a deeper understanding of a series of oxidation phenomena in Li-ion battery cathode materials and helps paving the way to the exploration of new energy storage materials with improved electrochemical performances

Can investments in manure technology reduce nutrient leakage to the Baltic Sea?

In this study, quantitative models of the agricultural sector and nutrient transport and cycling are used to analyse the impacts in the Baltic Sea of replacing the current Greening measures of the EU’s Common Agricultural Policy with a package of investments in manure handling. The investments aim at improving nutrient utilization and reducing nitrogen leaching, based on the assumption that lagging farms and regions can catch up with observed good practice. Our results indicate that such investments could reduce nitrogen surpluses in agriculture by 18% and nitrogen concentrations in the Baltic Sea by 1 to 9% depending on the basin. The Greening measures, in contrast, are found to actually increase nitrogen leaching.Peer reviewe

Electrodeposited Cu2Sb as anode material for 3-dimensional Li-ion microbatteries

An increasing demand on high energy and power systems has arisen not only with the development of electric vehicle (EV), hybrid electric vehicle (HEV), telecom, and mobile technologies, but also for specific applications such as powering of microelectronic systems. To power those microdevices, an extra variable is added to the equation: a limited footprint area. Three-dimensional (3D) microbatteries are a solution to combine high-density energy and power. In this work, we present the formation of Cu2Sb onto three-dimensionally architectured arrays of Cu current collectors. Sb electrodeposition conditions and annealing post treatment are discussed in light of their influence on the morphology and battery performances. An increase of cycling stability was observed when Sb was fully alloyed with the Cu current collector. A subsequent separator layer was added to the 3D electrode when optimized. Equivalent capacity values are measured for at least 20 cycles. Work is currently devoted to the identification of the causes of capacity fading

On the Capacity Losses Seen for Optimized Nano‐Si Composite Electrodes in Li‐Metal Half‐Cells

While the use of silicon‐based electrodes can increase the capacity of Li‐ion batteries considerably, their application is associated with significant capacity losses. In this work, the influences of solid electrolyte interphase (SEI) formation, volume expansion, and lithium trapping are evaluated for two different electrochemical cycling schemes using lithium‐metal half‐cells containing silicon nanoparticle–based composite electrodes. Lithium trapping, caused by incomplete delithiation, is demonstrated to be the main reason for the capacity loss while SEI formation and dissolution affect the accumulated capacity loss due to a decreased coulombic efficiency. The capacity losses can be explained by the increasing lithium concentration in the electrode causing a decreasing lithiation potential and the lithiation cut‐off limit being reached faster. A lithium‐to‐silicon atomic ratio of 3.28 is found for a silicon electrode after 650 cycles using 1200 mAhg−1 capacity limited cycling. The results further show that the lithiation step is the capacity‐limiting step and that the capacity losses can be minimized by increasing the efficiency of the delithiation step via the inclusion of constant voltage delithiation steps. Lithium trapping due to incomplete delithiation consequently constitutes a very important capacity loss phenomenon for silicon composite electrodes

Calcium : A Crucial Potentiator for Efficient Enzyme Digestion of the Human Pancreas

Background: Effective digestive enzymes are crucial for successful islet isolation. Supplemental proteases are essential because they synergize with collagenase for effective pancreatic digestion. The activity of these enzymes is critically dependent on the presence of Ca2+ ions at a concentration of 5-10 mM. The present study aimed to determine the Ca2+ concentration during human islet isolation and to ascertain whether the addition of supplementary Ca2+ is required to maintain an optimal Ca2+ concentration during the various phases of the islet isolation process. Methods: Human islets were isolated according to standard methods and isolation parameters. Islet quality control and the number of isolations fulfilling standard transplantation criteria were evaluated. Ca2+ was determined by using standard clinical chemistry routines. Islet isolation was performed with or without addition of supplementary Ca2+ to reach a Ca2+ of 5 mM. Results: Ca2+ concentration was markedly reduced in bicarbonate-based buffers, especially if additional bicarbonate was used to adjust the pH as recommended by the Clinical Islet Transplantation Consortium. A major reduction in Ca2+ concentration was also observed during pancreatic enzyme perfusion, digestion, and harvest. Additional Ca2+ supplementation of media used for dissolving the enzymes and during digestion, perfusion, and harvest was necessary in order to obtain the concentration recommended for optimal enzyme activity and efficient liberation of a large number of islets from the human pancreas. Conclusions: Ca2+ is to a large extent consumed during clinical islet isolation, and in the absence of supplementation, the concentration fell below that recommended for optimal enzyme activity. Ca2+ supplementation of the media used during human pancreas digestion is necessary to maintain the concentration recommended for optimal enzyme activity. Addition of Ca2+ to the enzyme blend has been implemented in the standard isolation protocols in the Nordic Network for Clinical Islet Transplantation.Peer reviewe

What Should We Agree on about the Repugnant Conclusion?

The Repugnant Conclusion served an important purpose in catalyzing and inspiring the pioneering stage of population ethics research. We believe, however, that the Repugnant Conclusion now receives too much focus. Avoiding the Repugnant Conclusion should no longer be the central goal driving population ethics research, despite its importance to the fundamental accomplishments of the existing literature