Starting with coal, followed by petroleum oil and natural gas, the utilization of fossil fuels has allowed the fast and unprecedented development of human society. However, the burning of these resources in ever increasing pace is accompanied by large amounts of anthropogenic CO2 emissions, which are outpacing the natural carbon cycle, causing adverse global environmental changes, the full extent of which is still unclear. Even through fossil fuels are still abundant, they are nevertheless limited and will, in time, be depleted. Chemical recycling of CO2 to renewable fuels and materials, primarily methanol, offers a powerful alternative to tackle both issues, that is, global climate change and fossil fuel depletion. The energy needed for the reduction of CO2 can come from any renewable energy source such as solar and wind. Methanol, the simplest C1 liquid product that can be easily obtained from any carbon source, including biomass and CO2, has been proposed as a key component of such an anthropogenic carbon cycle in the framework of a "Methanol Economy". Methanol itself is an excellent fuel for internal combustion engines, fuel cells, stoves, etc. It's dehydration product, dimethyl ether, is a diesel fuel and liquefied petroleum gas (LPG) substitute. Furthermore, methanol can be transformed to ethylene, propylene and most of the petrochemical products currently obtained from fossil fuels. The conversion of CO2 to methanol is discussed in detail in this review.

With rising levels of CO 2 in our atmosphere, technologies capable of converting CO 2 into useful products have become more valuable. The field of electrochemical CO 2 reduction is reviewed here, with sections on mechanism, formate (formic acid) production, carbon monoxide production, reduction to higher products (methanol, methane, etc.), use of flow cells, high pressure approaches, mo-lecular catalysts, non-aqueous electrolytes, and solid oxide electrolysis cells. These diverse approaches to electrochemical CO 2 reduction are compared and contrasted, emphasizing potential processes that would be feasible for large-scale use. Although the focus is on recent reports, highlights of older reports are also included due to their important contributions to the field, particularly for high-rate electrolysis.

The concept of scale in human geography has been profoundly transformed over the past 20 years. And yet, despite the insights that both empirical and theoretical research on scale have generated, there is today no consensus on what is meant by the term or how it should be operationalized. In this paper we critique the dominant -hierarchical -conception of scale, arguing it presents a number of problems that cannot be overcome simply by adding on to or integrating with network theorizing. We thereby propose to eliminate scale as a concept in human geography. In its place we offer a different ontology, one that so flattens scale as to render the concept unnecessary. We conclude by addressing some of the political implications of a human geography without scale.key words scale global-local hierarchy network flat ontology social site

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Understanding the factors limiting Li + charge transfer kinetics in Li-ion batteries is essential in improving the rate performance, especially at lower temperatures. The Li + charge transfer process involved in the lithium intercalation of graphite anode includes the step of de-solvation of the solvated Li + in the liquid electrolyte and the step of transport of Li + in the preformed solid electrolyte interphase (SEI) on electrodes until the Li + accepts an electron at the electrode and becomes a Li in the electrode. Whether the de-solvation process or the Li + transport through the SEI is a limiting step depends on the nature of the interphases at the electrode and electrolyte interfaces. Several examples involving the electrode materials such as graphite, lithium titanate (LTO), lithium iron phosphate (LFP), lithium nickel cobalt aluminum oxide (NCA) and solid Li + conductor such as lithium lanthanum titanate or Li-Al-Ti-phosphate are reviewed and discussed to clarify the conditions at which either the de-solvation or the transport of Li + in SEI is dominating and how the electrolyte components affect the activation energy of Li + charge transfer kinetics. How the electrolyte additives impact the Li + charge transfer kinetics at both the anode and the cathode has been examined at the same time in 3-electrode full cells. The resulting impact on Li + charge transfer resistance, R ct , and activation energy, E a , at both electrodes are reported and discussed. To improve the power performance of Li-ion batteries, it is important to understand the factors that limit the Li + charge transfer kinetics. Li-ion batteries comprised of a graphite anode and a lithium cobalt oxide cathode in an electrolyte consisting of 1 M LiPF 6 in ethylene carbonate (EC)-dimethyl carbonate (DMC)-diethyl carbonate (DEC) carbonate solvent mixture could not deliver their room temperature capacity at a rate of C/2 at −30 and −40• C. 1 When DEC was replaced by a linear ester solvent, such as ethyl acetate (EA) or methyl butyrate (MB), the Li-ion batteries at −30 and −40• C could deliver over 80% of their room temperature capacity at the same rate.2 When the LiPF 6 salt is replaced by lithium bis(oxalato)borate (LiBOB) in EC-ethyl methyl carbonate (EMC) (1:1 wt ratio) carbonate solvent mixture, the impedance of the graphite-electrolyte interface measured using graphite/Li half cells in the electrolyte with LiBOB is three times that in the electrolyte with LiPF 6 .3 These examples illustrate that the electrolyte components play crucial roles in affecting Li + charge transfer kinetics in Li-ion batteries.The Li + charge transfer process starts from the solvated Li + in the electrolyte to the reception of an electron (e − ) from the electrode and becomes Li (i.e., Li x C in graphitic anodes). This involves the desolvation step of Li + before entering into a layer of solid electrolyte interphases, or SEI, that is often referred to that on the anode such as carbonaceous materials, and the diffusion step of Li + through the SEI, which is pre-form...