Advances in the study of coke formation over zeolite catalysts in the methanol-to-hydrocarbon process

Methanol-to-hydrocarbon (MTH) process over acidic zeolite catalysts has been widely utilised to yield many types of hydrocarbons, some of which are eventually converted into the highly dehydrogenated (graphitized) carbonaceous species (cokes). The coking process can be divided into two parallel pathways based on the accepted hydrocarbon pool theory. From extensive investigations, it is reasonable to conclude that inner zeollite cavity/channel reactions at acidic sites generate cokes. However, coke formation and accumulation over the zeolite external surfaces play a major role in reaction deactivation as they contribute a great portion to the total coke amount. Herein we have reviewed previous literatures and included some recent works from KOPRC in understanding the nature and mechanism of coke formation, particularly during an H-ZSM-5 catalysed MTH reaction. We specially conclude that rapid aromatics formation at the zeolite crystalite edges is the main reason for later stage coke accumulation on the zeolite external surfaces. Accordingly, the catalyst deactivation is in a great certain to arise at those edge areas due to having the earliest contact with the incoming methanol reactant. The final coke structure is therefore built up with layers of poly-aromatics, as the potential sp2 carbons leading to pre-graphite structure. We have proposed a coke formation model particularly for the acidic catalyst, which we believe will be of assistance in understanding—and hence minimising—the coke formation mechanisms

Wax: A benign hydrogen-storage material that rapidly releases H2-rich gases through microwave-assisted catalytic decomposition

Hydrogen is often described as the fuel of the future, especially for application in hydrogen powered fuel-cell vehicles (HFCV’s). However, its widespread implementation in this role has been thwarted by the lack of a lightweight, safe, on-board hydrogen storage material. Here we show that benign, readily-available hydrocarbon wax is capable of rapidly releasing large amounts of hydrogen through microwave-assisted catalytic decomposition. This discovery offers a new material and system for safe and efficient hydrogen storage and could facilitate its application in a HFCV. Importantly, hydrogen storage materials made of wax can be manufactured through completely sustainable processes utilizing biomass or other renewable feedstocks

Exorcising Grice’s ghost : an empirical approach to studying intentional communication in animals

Language’s intentional nature has been highlighted as a crucial feature distinguishing it from other communication systems. Specifically, language is often thought to depend on highly structured intentional action and mutual mindreading by a communicator and recipient. Whilst similar abilities in animals can shed light on the evolution of intentionality, they remain challenging to detect unambiguously. We revisit animal intentional communication and suggest that progress in identifying analogous capacities has been complicated by (i) the assumption that intentional (that is, voluntary) production of communicative acts requires mental-state attribution, and (ii) variation in approaches investigating communication across sensory modalities. To move forward, we argue that a framework fusing research across modalities and species is required. We structure intentional communication into a series of requirements, each of which can be operationalised, investigated empirically, and must be met for purposive, intentionally communicative acts to be demonstrated. Our unified approach helps elucidate the distribution of animal intentional communication and subsequently serves to clarify what is meant by attributions of intentional communication in animals and humans

North Morecambe Terminal, Barrow, Ground Stabilisation and Pile Foundations

Very poor ground conditions and soils that were susceptible to liquefaction to depths of up to 20m beneath the site were major problems for the construction of the largest natural gas processing terminal in Europe. An innovative foundation solution combining deep vibro compaction with short cast in place piles driven into the treated soils was adopted as both cost and programme effective. The Design and Build project also included advance civils work comprising earthworks, drainage and road construction. The contract started in September 1991 and was completed by October 1992, with the process plant programmed to be on-stream by October 1994. This paper describes the seismic aspects of the foundation solution

Human listeners' perception of behavioural context and core affect dimensions in chimpanzee vocalizations

Vocalizations linked to emotional states are partly conserved among phylogenetically related species. This continuity may allow humans to accurately infer affective information from vocalizations produced by chimpanzees. In two pre-registered experiments, we examine human listeners' ability to infer behavioural contexts (e.g. discovering food) and core affect dimensions (arousal and valence) from 155 vocalizations produced by 66 chimpanzees in 10 different positive and negative contexts at high, medium or low arousal levels. In experiment 1, listeners (n = 310), categorized the vocalizations in a forced-choice task with 10 response options, and rated arousal and valence. In experiment 2, participants (n = 3120) matched vocalizations to production contexts using yes/no response options. The results show that listeners were accurate at matching vocalizations of most contexts in addition to inferring arousal and valence. Judgments were more accurate for negative as compared to positive vocalizations. An acoustic analysis demonstrated that, listeners made use of brightness and duration cues, and relied on noisiness in making context judgements, and pitch to infer core affect dimensions. Overall, the results suggest that human listeners can infer affective information from chimpanzee vocalizations beyond core affect, indicating phylogenetic continuity in the mapping of vocalizations to behavioural contexts

Abilities to explicitly and implicitly infer intentions from actions in adults with autism spectrum disorder

Previous research suggests that Autism Spectrum Disorder (ASD) might be associated with impairments on implicit but not explicit mentalizing tasks. However, such comparisons are made difficult by the heterogeneity of stimuli and the techniques used to measure mentalizing capabilities. We tested the abilities of 34 individuals (17 with ASD) to derive intentions from others’ actions during both explicit and implicit tasks and tracked their eye-movements. Adults with ASD displayed explicit but not implicit mentalizing deficits. Adults with ASD displayed typical fixation patterns during both implicit and explicit tasks. These results illustrate an explicit mentalizing deficit in adults with ASD, which cannot be attributed to differences in fixation patterns

Microwaves effectively examine the extent and type of coking over acid zeolite catalysts

Coking leads to the deactivation of solid acid catalyst. This phenomenon is a ubiquitous problem in the modern petrochemical and energy transformation industries. Here, we show a method based on microwave cavity perturbation analysis for an effective examination of both the amount and the chemical composition of cokes formed over acid zeolite catalysts. The employed microwave cavity can rapidly and non-intrusively measure the catalytically coked zeolites with sample full body penetration. The overall coke amount is reflected by the obtained dielectric loss (ε″) value, where different coke compositions lead to dramatically different absorption efficiencies (ε″/cokes' wt%). The deeper-dehydrogenated coke compounds (e.g., polyaromatics) lead to an apparently higher ε″/wt% value thus can be effectively separated from lightly coked compounds. The measurement is based on the nature of coke formation during catalytic reactions, from saturated status (e.g., aliphatic) to graphitized status (e.g., polyaromatics), with more delocalized electrons obtained for enhanced Maxwell-Wagner polarization.Catalyst deactivation by coke deposition is a major drawback in industrial processes. Here, the authors show a non-intrusive microwave cavity perturbation technique as a powerful tool to determine the nature and extent of coke accumulation in industrially-relevant zeolite catalysts

Speaker- versus listener-oriented disfluency: A re-examination of arguments and assumptions from autism spectrum disorder

We re-evaluate conclusions about disfluency production in high-functioning forms of autism spectrum disorder (HFA). Previous studies examined individuals with HFA to address a theoretical question regarding speaker- and listener-oriented disfluencies. Individuals with HFA tend to be self-centric and have poor pragmatic language skills, and should be less likely to produce listener-oriented disfluency. However, previous studies did not account for individual differences variables that affect disfluency. We show that both matched and unmatched controls produce fewer repairs than individuals with HFA. For silent pauses, there was no difference between matched controls and HFA, but both groups produced more than unmatched controls. These results identify limitations in prior research and shed light on the relationship between autism spectrum disorders and disfluent speech

Pseudoreplication in Primate Communication Research : 10 Years On

Pseudoreplication is the statistical error of collecting numerous datapoints from a single unit (such as an individual), which are not independent, and applying statistical methods that assume independence of data. Importantly, pseudoreplication increases the chances of Type 1 errors (i.e., false positives), bringing findings and conclusions based on pseudoreplicated analyses into question. Ten years ago, Waller et al. (2013) published a paper highlighting the prevalence of statistical pseudoreplication throughout the nonhuman primate communication literature. In this current study, we examined the literature published since the original publication (between 2009 and 2020; 348 papers) to assess whether pseudoreplication is still as widespread as it was, if it has become more problematic, or if the field is beginning to overcome this issue. We find that there has been a significant decrease in pseudoreplication over the past ten years (38.6% then, compared with 23.0% now). This reduction in pseudoreplication appears to be associated with an increase in the use of multilevel models throughout primatology (which allow for nonindependent data to be nested appropriately). Pseudoreplication was historically more prevalent in research using observational (vs. experimental) methods and those working with wild (vs. captive) primates. However, these biases do not seem to exist in more recent literature with a more comparable likelihood of pseudoreplication seen across the field regardless of methods. Although these current findings relate specifically to primate communication research, we think they will translate broadly across nonhuman communication research, and throughout biology. We continue to emphasise the need to monitor these issues, as although now seen at much lower rates, pseudoreplication is still present and therefore potentially impacting the accuracy of findings

Developing an analytical framework for assessing progress toward ecosystem-based management

Ecosystem-based management (EBM) has become a key instrument of contemporary environmental policy and practice. Given the increasingly important role of EBM, there is an urgent need for improved analytical approaches to assess if and to what extent EBM has been accomplished in any given case. Drawing on the vast literature on EBM, we identify five key ecosystem aspects for assessment. By linking these aspects to four phases of management, we develop an interdisciplinary, analytical framework that enables a high-resolution and systematic assessment of the degree of specificity and integration of ecosystem aspects in an EBM. We then apply the framework to evaluate five coastal EBM initiatives in Sweden, four on the Baltic coast and one on the west coast. Our results demonstrate our framework’s usefulness for in-depth and continuous assessments of processes aiming for EBM, and also provide an empirical basis for inferences about the key challenges for successful EBM. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1007/s13280-015-0655-7) contains supplementary material, which is available to authorized users