72 research outputs found

    A spin- and angle-resolving photoelectron spectrometer

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    A new type of hemispherical electron energy analyzer that permits angle and spin resolved photoelectron spectroscopy has been developed. The analyzer permits standard angle resolved spectra to be recorded with a two-dimensional detector in parallel with spin detection using a mini-Mott polarimeter. General design considerations as well as technical solutions are discussed and test results from the Au(111) surface state are presented

    Potentials in Li-Ion Batteries Probed by Operando Ambient Pressure Photoelectron Spectroscopy

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    The important electrochemical processes in a battery happen at the solid/liquid interfaces. Operando ambient pressure photoelectron spectroscopy (APPES) is one tool to study these processes with chemical specificity. However, accessing this crucial interface and identifying the interface signal are not trivial. Therefore, we present a measurement setup, together with a suggested model, exemplifying how APPES can be used to probe potential differences over the electrode/electrolyte interface, even without direct access to the interface. Both the change in electron electrochemical potential over the solid/liquid interface, and the change in Li chemical potential of the working electrode (WE) surface at Li-ion equilibrium can be probed. Using a Li4Ti5O12 composite as a WE, our results show that the shifts in kinetic energy of the electrolyte measured by APPES can be correlated to the electrochemical reactions occurring at the WE/electrolyte interface. Different shifts in kinetic energy are seen depending on if a phase transition reaction occurs or if a single phase is lithiated. The developed methodology can be used to evaluate charge transfer over the WE/electrolyte interface as well as the lithiation/delithiation mechanism of the WE

    Captured by Evil: The Idea of Corruption in Law

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    Corruption is one of the most powerful words in the English language. When it comes to the treatment of corruption by law, however, corruption is a troubled concept. With increasing recognition of the costs of corruption for economic development, democratic governance, international aid programs, and other world goals, attempts to articulate what this destructive force is have led to an avalanche of theoretical writing. In the last fifteen years, corruption has been variously defined as the violation of law, a public servant\u27s breach of public duty, an agent\u27s betrayal of a principal\u27s interests, the pursuit of secrecy, the denial of equality in political influence, and other ways. In the end, however, all of these efforts fall short. Corruption is more than law-breaking: it is more than breaching public duties. To say that A is a thief or that A has breached his duty is not to say that A is corrupt. The latter is far more powerful, far more emotional, far more essential than the others. It is more than secrecy, or the denial of equal opportunity. It is a searing indictment, somehow, not only of A\u27s act but of A\u27s character. It is a statement not only of what A has done, but of what A has become. Corruption is, I argue, a far more powerful idea than these existing legal understandings have articulated: it is the idea of capture by evil, the possession of the individual by evil, in law. Just as we once believed in corruption of the blood in American law, which decreed that offspring of those who had committed crimes were believed to be irrevocably tainted by their parents\u27 depravity, so we still retain - through the idea of corruption - the belief that individual evil extends beyond acts of wrongdoing, or the denial of equal opportunity, or breach of the public trust. It is this idea of corruption, I argue - the idea of capture by evil - that, although unarticulated, drives our understandings of corruption in law. It drives our understanding of corrupt judges, who, once corrupt, we believe will act so in every case. It drives our understanding of campaign finance reform, where we fear deep corruption of the process from the occurrence of corrupt acts. It drives our understanding of corruption as a systemic effect and systemic influence, which presents institutional dangers that are greater than other crimes, and that requires purgation rather than simple law enforcement. This Article explores this deeper understanding of corruption, its impacts in areas such as judicial corruption and campaign finance reform, and its implications for the principle of the rule of law

    A Roadmap for Transforming Research to Invent the Batteries of the Future Designed within the European Large Scale Research Initiative BATTERY 2030+

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    This roadmap presents the transformational research ideas proposed by “BATTERY 2030+,” the European large-scale research initiative for future battery chemistries. A “chemistry-neutral” roadmap to advance battery research, particularly at low technology readiness levels, is outlined, with a time horizon of more than ten years. The roadmap is centered around six themes: 1) accelerated materials discovery platform, 2) battery interface genome, with the integration of smart functionalities such as 3) sensing and 4) self-healing processes. Beyond chemistry related aspects also include crosscutting research regarding 5) manufacturability and 6) recyclability. This roadmap should be seen as an enabling complement to the global battery roadmaps which focus on expected ultrahigh battery performance, especially for the future of transport. Batteries are used in many applications and are considered to be one technology necessary to reach the climate goals. Currently the market is dominated by lithium-ion batteries, which perform well, but despite new generations coming in the near future, they will soon approach their performance limits. Without major breakthroughs, battery performance and production requirements will not be sufficient to enable the building of a climate-neutral society. Through this “chemistry neutral” approach a generic toolbox transforming the way batteries are developed, designed and manufactured, will be created

    The violent youth of bright and massive cluster galaxies and their maturation over 7 billion years

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    In this study, we investigate the formation and evolution mechanisms of the brightest cluster galaxies (BCGs) over cosmic time. At high redshift (z ∼ 0.9), we selected BCGs and most massive cluster galaxies (MMCGs) from the Cl1604 supercluster and compared them to low-redshift (z ∼ 0.1) counterparts drawn from the MCXC meta-catalogue, supplemented by Sloan Digital Sky Survey imaging and spectroscopy. We observed striking differences in the morphological, colour, spectral, and stellar mass properties of the BCGs/MMCGs in the two samples. High-redshift BCGs/MMCGs were, in many cases, star-forming, late-type galaxies, with blue broad-band colours, properties largely absent amongst the low-redshift BCGs/MMCGs. The stellar mass of BCGs was found to increase by an average factor of 2.51 ± 0.71 from z ∼ 0.9 to z ∼ 0.1. Through this and other comparisons, we conclude that a combination of major merging (mainly wet or mixed) and in situ star formation are the main mechanisms which build stellar mass in BCGs/MMCGs. The stellar mass growth of the BCGs/MMCGs also appears to grow in lockstep with both the stellar baryonic and total mass of the cluster. Additionally, BCGs/MMCGs were found to grow in size, on average, a factor of ∼3, while their average Sérsic index increased by ∼0.45 from z ∼ 0.9 to z ∼ 0.1, also supporting a scenario involving major merging, though some adiabatic expansion is required. These observational results are compared to both models and simulations to further explore the implications on processes which shape and evolve BCGs/MMCGs over the past ∼7 Gyr
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