Sources of uncertainty in the closed-loop supply chain of lithium-ion batteries for electric vehicles

Due to increasing demand for electric vehicles and short innovation circles of battery, production, and recycling technology, different uncertainties need to be faced at different stages of the supply chain. However, a qualitative analysis of the uncertainties and their sources is missing. Therefore, in this paper the authors propose an empirical approach to the identification of uncertainty occurring in the closed-loop supply chain of lithium-ion batteries from electric vehicles (uncertainty in supply, process, demand, control, and environmental uncertainty). The investigation methodology consists of a content analysis of press media documents related to electric vehicles and the automotive industry. The final content analysis comprises 102 evidences of uncertainty. Consequently, the evidences of uncertainty found are classified in a spectrum between statistical uncertainty and total ignorance (levels of uncertainty). Graphs and data are described to provide detailed information. The results signal predominant environmental uncertainty besides the uncertainty within control and supply of the closed-loop. A conclusion on the investigation shows cobalt as a raw material responsible for increasing uncertainty (boomerang effect). Additionally, the content analysis evidences uncertainty with the availability, quantity, stock control policies, government regulations, and political instability with cobalt, lithium, and nickel.publishersversionpublishe

Chemical Characterization and Source Apportionment of Household Fine Particulate Matter in Rural, Peri-urban, and Urban West Africa

Household air pollution in sub-Saharan Africa and other developing regions is an important cause of disease burden. Little is known about the chemical composition and sources of household air pollution in sub-Saharan Africa, and how they differ between rural and urban homes. We analyzed the chemical composition and sources of fine particles (PM2.5) in household cooking areas of multiple neighborhoods in Accra, Ghana, and in peri-urban (Banjul) and rural (Basse) areas in The Gambia. In Accra, biomass burning accounted for 39–62% of total PM2.5 mass in the cooking area in different neighborhoods; the absolute contributions were 10–45 μg/m3. Road dust and vehicle emissions comprised 12–33% of PM2.5 mass. Solid waste burning was also a significant contributor to household PM2.5 in a low-income neighborhood but not for those living in better-off areas. In Banjul and Basse, biomass burning was the single dominant source of cooking-area PM2.5, accounting for 74–87% of its total mass; the relative and absolute contributions of biomass smoke to PM2.5 mass were larger in households that used firewood than in those using charcoal, reaching as high as 463 μg/m3 in Basse homes that used firewood for cooking. Our findings demonstrate the need for policies that enhance access to cleaner fuels in both rural and urban areas, and for controlling traffic emissions in cities in sub-Saharan Africa

Baryonic Effect on chi_cJ Suppression in Au+Au Collisions at RHIC Energies

We predict that initially produced chi_cJ mesons at low transverse momentum in the central rapidity region are almost dissociated by nucleons and antinucleons in hadronic matter produced in central Au+Au collisions at RHIC energies sqrt {s_{NN}}= 130 and 200 GeV. In calculations the nucleon and antinucleon distributions in hadronic matter are results of evolution from their freeze-out distributions which well fit the experimental p_T spectra of proton and antiproton. Any measured chi_cJ mesons at low p_T are generated from deconfined matter and give an explicit proof of regeneration mechanism (recombination mechanism).Comment: 10 pages, 3 figures, Latex, a discussion added to the referenc

Biomolecular characterization of 3500-year-old ancient Egyptian mummification balms from the Valley of the Kings

Ancient Egyptian mummification was practiced for nearly 4000 years as a key feature of some of the most complex mortuary practices documented in the archaeological record. Embalming, the preservation of the body and organs of the deceased for the afterlife, was a central component of the Egyptian mummification process. Here, we combine GC-MS, HT-GC-MS, and LC-MS/MS analyses to examine mummification balms excavated more than a century ago by Howard Carter from Tomb KV42 in the Valley of the Kings. Balm residues were scraped from now empty canopic jars that once contained the mummified organs of the noble lady Senetnay, dating to the 18th dynasty, ca. 1450 BCE. Our analysis revealed balms consisting of beeswax, plant oil, fats, bitumen, Pinaceae resins, a balsamic substance, and dammar or Pistacia tree resin. These are the richest, most complex balms yet identified for this early time period and they shed light on balm ingredients for which there is limited information in Egyptian textual sources. They highlight both the exceptional status of Senetnay and the myriad trade connections of the Egyptians in the 2nd millennium BCE. They further illustrate the excellent preservation possible even for organic remains long removed from their original archaeological context

An imagined past?: Nomadic narratives in Central Asian archaeology

Nomads, or highly specialized mobile pastoralists, are prominent features in Central Asian archaeology, and they are often depicted in direct conflict with neighboring sedentary peoples. However, new archaeological findings are showing that the people who many scholars have called nomads engaged in a mixed economic system of farming and herding. Additionally, not all of these peoples were as mobile as previously assumed, and current data suggest that a portion of these purported mobile populations remained sedentary for much or all of the year, with localized ecological factors directing economic choices. In this article, we pull together nine complementary lines of evidence from the second through the first millennia BC to illustrate that in eastern Central Asia, a complex economy existed. While many scholars working in Eurasian archaeology now acknowledge how dynamic paleoeconomies were, broader arguments are still tied into assumptions regarding specialized economies. The formation of empires or polities, changes in social orders, greater political hierarchy, craft specialization?notably, advanced metallurgy?mobility and migration, social relations, and exchange have all been central to the often circular arguments made concerning so-called nomads in ancient Central Asia. The new interpretations of mixed and complex economies more effectively situate Central Asia into a broader global study of food production and social complexity.- Geographic Focus of This Discussion - The Nomadic Bias Macrobotanical Data Microbotanical Data Isotope Studies Ethnographic and Ethnohistoric Analogies Sedentary Occupation Structures - Villages and Fortified Sites - Farmsteads (Homesteads) Material Culture Evidence for Economy Nonportable Material Culture Zooarchaeology Written Sources Discussion - Two Millennia of Political Agendas - Arguments Used to Support Nomadic Models Conclusion Comments Repl

Strength of bacterial adhesion on nanostructured surfaces quantified by substrate morphometry

Microbial adhesion and the subsequent formation of resilient biofilms at surfaces are decisively influenced by substrate properties, such as the topography. To date, studies that quantitatively link surface topography and bacterial adhesion are scarce, as both are not straightforward to quantify. To fill this gap, surface morphometry combined with single-cell force spectroscopy was performed on surfaces with irregular topographies on the nano-scale. As surfaces, hydrophobized silicon wafers were used that were etched to exhibit surface structures in the same size range as the bacterial cell wall molecules. The surface structures were characterized by a detailed morphometric analysis based on Minkowski functionals revealing both qualitatively similar features and quantitatively different extensions. We find that as the size of the nanostructures increases, the adhesion forces decrease in a way that can be quantified by the area of the surface that is available for the tethering of cell wall molecules. In addition, we observe a bactericidal effect, which is more pronounced on substrates with taller structures but does not influence adhesion. Our results can be used for a targeted development of 3D-structured materials for/against bio-adhesion. Moreover, the morphometric analysis can serve as a future gold standard for characterizing a broad spectrum of material structures. © The Royal Society of Chemistry 2019