• What makes a book tweet popular? Analysis of the most retweeted content posted by Spanish and non-Spanish book publishers

      Mas-Bleda, Amalia; Makita, Meiko; Mrva-Montoya, Agata; Thelwall, Mike (Consejo Superior de Investigaciones Científicas, 2022-12-31)
      The aim of this article is to identify content-related features of the most retweeted messages posted by Spanish and non-Spanish book publishers on Twitter. A content analysis has been conducted to identify the topic of the tweets and whether they include book title hashtags, images and hyperlinks, and if so, what the images are about and where the links point to. As a complement, a word association analysis has been carried out to determine which terms are associated with each of the different publishers. Overall, publishers tend to tweet about themselves and their books for marketing purposes. About half of the publishers have Twitter accounts. Spanish publishers’ tweets often contain literary quotes, while the top tweets by non-Spanish publishers are more likely to contain free prize draws. Publishers seeking to engage with potential readers on Twitter could consider quotes and giveaways to build their audience, in addition to tagging author @usernames in book related posts to help reach the author’s network.
    • Time-dependent thixotropic behaviours of lead-free Sn-Ag-Cu (SAC) solder pastes and flux mediums used in electronic assemblies

      Mallik, S; Ekere, Nduka; Depiver, Joshua (David Publishing, 2022-12-31)
      Solder pastes are widely used as crucial joining material in microelectronic assemblies. This study investigates time-depended behaviours of paste materials (solder pastes and flux mediums) in relation to their transportation, storage, handling and applications. Two fluxes and four commercially available lead-free solder pastes prepared from those fluxes were evaluated. Two rheological test methods – ‘hysteresis loop test’ and ‘step shear test’ were adapted, taking account of actual shear profile of solder pastes and flux mediums. Within hysteresis loop tests, samples were sheared for both single and multiple cycles, with increasing and decreasing shear rates. These tests provided a quick and straightforward way of benchmarking time-depended structural breakdown and build-up of paste materials. The test results also provided an effective means of predicting how the pastes will behave during their use, such as at various stages of the stencil printing process. Step shear tests were performed by applying a sequence of stepwise increase in shear rates. The step-wise increase in shear rate has influenced the timedependent behaviours of solder paste samples and flux mediums. The result from the stepshear-test implies that the build-up of solder paste structure depends mainly on both the previous shear history and the intensity of structural break-down.
    • The impact of disruptive events on built environment degree apprenticeship delivery - A case study of COVID-19

      Oloke, David; Gyoh, Louis; Daniel, Emmanuel Itodo; Oladinrin, Olugbenga Timo; Abdallah, Nagwan (Emerald, 2022-12-31)
      Purpose: This study aims to understand the impact of the covid-19 pandemic disruptive event on delivery of the built environment degree apprentice programme in higher education in the UK and identify the key strategies to minimise the effect. Design/methodology/approach A qualitative approach was used to collect and analyse data from a sample set of built environment degree apprenticeship stakeholders. Semi-structured interviews was conducted with seventeen key stakeholders to collate emerging themes on their perceptions of the impacts of the pandemic and strategies to adopted to minimise it. Findings: The investigation reveals that the core impacts of covid-19 on the apprentices training programme are lack of access to the site, furlough, limited access to off the job training, limited interaction with tutors and peers, too much time on the screen, limited pastoral care and lack of contact with a mentor. The census from the research participants is that despite the development and gain with the various virtual platform used during pandemic physical meetings with their mentor remain pivotal to the built environment apprentices learning and training. Practical implications: The results provide relevant stakeholders and actors supporting degree apprentices training programmes (training providers and employers, among others) with the information needed to improve the delivery of Built Environment degree apprenticeship training programmes during a disruptive event covid-19. Originality: The principal scientific significance of the current study to education and training in the built environment lies in its presentation of empirical evidence on the impact of the covid-19 pandemic on degree apprentice's programme in the built environment and strategies to minimise the effect, which has not been documented.
    • A Brief guide to polymerization terminology (IUPAC Technical Report)

      Luscombe, Christine K; Moad, Graeme; Hiorns, Roger C; Jones, Richard G; Keddie, Daniel J; Matson, John B; Merna, Jan; Nakano, Tamaki; Russell, Gregory T; Topham, Paul D (Walter de Gruyter, 2022-12-31)
      Introduction. The use of self-consistent terminology to describe polymerizations is important for litigation, patents, research and education. Imprecision in these areas can be both costly and confusing. To address this situation the International Union of Pure and Applied Chemistry (IUPAC) has made recommendations, which are summarized below. References and hyperlinks lead to source documents. Screen tips contain definitions published in IUPAC recommendations.
    • Evaluating the effects of indoor air quality on teacher performance using artificial neural network

      Alzahrani, Hamdan; Arif, Mohammed; Kaushik, Amit; Rana, Muhammad Qasim; Aburas, Hani (Emerald, 2022-12-31)
      Purpose - Indoor Air Quality has a direct impact on occupant health and productivity. Understanding the effect of Indoor Air Quality (IAQ) in educational buildings is essential in both the design and construction phases for decisionmakers. Hence, it is equally important to recognise and appreciate the influence of design judgements on occupants' performance, especially on teacher and students. Design - This study aims to evaluate the effect of IAQ on teachers' performance. This study would deliver air quality requirements to BIM-led school projects. the methodology of the research approach uses quasi-experiment using questionnaire surveys and physical measurements of indoor air parameters to associate correlation and deduction. A technical college building in Saudi Arabia was used for the case study. The study developed an Artificial Neural Network model to define and predict relationships between teachers' performance and indoor air quality. Findings - This paper highlights a detailed investigation into the impact of indoor air quality via direct parameters (relative humidity, ventilation rates and carbon dioxide) on teacher performance. Research findings also indicate an optimal relative humidity with 65%, ranging between 650 ppm to 750 ppm of CO2, and 0.4m/s ventilation rate. This ratio considered optimum records for both comfort and performance. Originality – This paper focused on teachers’ performance in Saudi Arabia and used Artificial Neural Networks to define and predict the relationship between performance and indoor air quality. There are few studies focusing on teachers’ performance in Saudi Arabia and very few that uses ANN in data analysis.
    • Efficacy of isatuximab with pomalidomide and dexamethasone in relapsed myeloma: Results of a UK-wide real-world dataset

      Djebbari, Faouzi; Rampotas, Alexandros; Vallance, Grant; Panitsas, Fotios; Basker, Nanda; Sangha, Gina; Salhan, Beena; Karim, Farheen; Al-Kaisi, Firas; Gudger, Amy; et al. (Lippincott, Williams & Wilkins, 2022-12-31)
      Real-world data on the efficacy and tolerability of isatuximab with pomalidomide and dexamethasone (IsaPomDex) in relapsed/refractory myeloma (RRMM) patients have not been reported. In this UK-wide retrospective study, IsaPomDex outcomes were evaluated across 24 routine care cancer centres. The primary endpoint was overall response rate (ORR). Secondary endpoints included progression-free survival (PFS), duration of response (DOR) for patients who achieved an objective response (≥PR), and adverse events (AEs). In a total cohort 107 patients, median follow up (IQR) was 12.1 months (10.1-18.6 months), median age (IQR) was 69 years (61-77). Median (IQR) Charlson Co-morbidity index (CCI) score was 3 (2- 4); 43% had e-GFR<60 ml/min. Median (IQR) number of prior therapies was 3 (3-3). Median (IQR) number of IsaPomDex cycles administered was 7 (3-13). ORR was 66.4%, with responses categorised as ≥VGPR: 31.8%, PR: 34.6%, SD: 15.9%, PD: 15% and unknown 2.8%. Median PFS was 10.9 months. Median DOR was 10.3 months There was no statistical difference in median PFS by age (<65: 10.2 vs. 65-74 13.2 vs. ≥75: 8.5 months, log-rank p=0.4157), by CCI score (<4: 10.2 months vs. ≥4: 13.2, log-rank p=0.6531), but inferior PFS was observed with renal impairment (≥60: 13.2 vs. <60: 7.9 months, log-rank p=0.0408). Median OS was 18.8 months. After a median of 4 cycles, any grade AEs were experienced by 87.9% of patients. The most common ≥G3 AEs were neutropenia (45.8%), infections (18.7%) and thrombocytopenia (14%). Our UK-wide IsaPomDex study demonstrated encouraging efficacy outcomes in the real-world, comparable to ICARIA-MM trial.
    • Research co-authorship 1900-2020: Continuous, universal, and ongoing expansion

      Thelwall, Mike; Maflahi, Nabeil (MIT Press, 2022-12-31)
      Research co-authorship is useful to combine different skillsets, especially for applied problems. Whilst it has increased over the last century, it is unclear whether this increase is universal across academic fields and which fields co-author the most and least. In response, this article assesses changes in the rate of journal article co-authorship 1900-2020 for all 27 Scopus broad fields and all 332 Scopus narrow fields. Whilst all broad fields have experienced reasonably continuous growth in co-authorship, in 2020 there were substantial disciplinary differences, from Arts and Humanities (1.3 authors) to Immunology and Microbiology (6 authors). All 332 Scopus narrow fields also experienced an increase in the average number of authors. Immunology and Classics are extreme Scopus narrow fields, as exemplified by 9.6 authors per Journal for ImmunoTherapy of Cancer article, whilst 93% of Trends in Classics articles were solo in 2020. The reason for this large difference seems to be the need for multiple complementary methods in Immunology, making it fundamentally a team science. Finally, the reasonably steady and universal increases in academic co-authorship over 121 years show no sign of slowing, suggesting that ever expanding teams are a central part of current professional science.
    • The high scholarly value of grey literature before and during Covid-19

      Kousha, Kayvan; Thelwall, Mike; Bickley, Matthew; RIILP, Faculty of Science and Engineering, University of Wolverhampton (Springer Nature, 2022-12-31)
      New academic knowledge in journal articles is partly built on peer reviewed research already published in journals or books. Academics can also draw from non-academic sources, such as the websites of organisations that publish credible information. This article investigates trends in the academic citing of this type of grey literature for 17 health, media, statistics, and large international organisations, with a focus on Covid-19. The results show substantial and steadily increasing numbers of citations to all 17 sites, with larger increases from 2019 to 2020. In 2020, Covid-19 citations to these websites were particularly common for news organisations, the WHO, and the UK Office for National Statistics, apparently for up-to-date information in the rapidly changing circumstances of the pandemic. Except for the UN, the most cited URLs of each organisation were not traditional report-like grey literature but were other types, such as news stories, data, statistics, and general guidance. The Covid-19 citations to most of these websites originated primarily from medical research, commonly for coronavirus data and statistics. Other fields extensively cited some of the non-health websites, as illustrated by social science (including psychology) studies often citing UNESCO. The results confirm that grey literature from major websites has become even more important within academia during the pandemic, providing up-to-date information from credible sources despite a lack of academic peer review. Researchers, reviewers, and editors should accept that it is reasonable to cite this information, when relevant, and evaluators should value academic work that supports these non-academic outputs.
    • Barriers and cost model of implementing unmanned aerial system (UAS) services in a decentralised system: Case of the Dominican Republic

      Reynoso Vanderhorst, Hamlet; Heesom, David; Suresh, Subashini; Renukappa, Suresh; Burnham, Keith J. (Emerald, 2022-05-16)
      Purpose – The aim of this paper is to identify the business barriers that influence cost of implementing UAS and its suitability for a decentralised system. Unmanned Aerial System (UAS), or drone, plays a role of data provider to AEC professionals within a decentralised system. However, exist disappointments in the execution and test of the effectiveness of the UAS. The reasons for these fails are not well elaborated in the literature. Hence, the study investigates the barriers and cost analysis of UAS that can be used for a decentralised case in which the UAS data is useful for multiple stakeholders and provide illustration of the interactions within this approach. Design/methodology/approach – This paper is part of a longitudinal project by utilising a qualitative method of interviewing 24 participants involved in the process of application of drones in the country of the Dominican Republic. The open-ended semi-structured interviews were composed for questions regarding the application of UAS, barriers, and business implications. The data gathered were transcribed and used thematic analysis for its interpretation. Later, conclusions of the barriers of UAS implementation in the organisation were analysed and a cost model was developed to identify a viable scenario. Findings – The paper provides empirical insights about the barriers and economic considerations faced in the implementation process of UAS. In this research were identified: 16 barriers in the implementation process at the management level, 8 types of cases of business relationships, and 13 business models. Furthermore, recommendations in being accountable for the dimensions and recurrent visits to the projects handled by the portfolio of the organisations were made, to prudently invest in this project management tool for construction. Practical implications – The paper includes barriers to consider before implementation, business implications, project examples and cost structure developed. Furthermore, the findings are fit theoretically into the context of a decentralised system. It was understood and contemplated that monitoring in open and outdoor spaces are the suitable approach for UAS implementations for decentralised system. The trend of decentralised autonomous organisations for transparency and efficiency of human tasks provides the foundations of human-robot interactions as well as the role of tokenisation of assets into the cyberspace. Therefore, the paper brings managers and technicians the implications for the future-proofing implementation of UAS. Research Limitations – Blockchain system is supported by UAS data and its tests require skills and resources that were outside of the scope of the main research intend regarding UAS implementation in construction. Word counts limited details in a certain degree. Furthermore, as these technologies are still under development, the assessment of the decentralised system, smart contract, and swarm technology was addressed conceptually and further research are encouraged in this field. Originality/value – This paper provides an overview of the implications of cost and the suitable scenarios for return of investment in the UAS implementation in the current stage of the technology development. In addition, the paper makes reference to decentralised systems, smart contracts and swarm technology as options in which reality capture technologies are essential for construction projects.
    • Nonlinear marine predator algorithm: A cost-effective optimizer for fair power allocation in NOMA-VLC-B5G networks

      Sadiq, Ali Safaa; Dekhordi, Amin Abdollahi; Mirjalili, Seyedali; Pham, Quoc Viet (Elsevier, 2022-05-11)
      This paper is an influential attempt to identify and alleviate some of the issues with the recently proposed optimization technique called the Marine Predator Algorithm (MPA). With a visual investigation of its exploratory and exploitative behavior, it is observed that the transition of search from being global to local can be further improved. As an extremely cost-effective method, a set of nonlinear functions is used to change the search patterns of the MPA algorithm. The proposed algorithm is called Nonlinear Marin Predator Algorithm (NMPA) is tested on a set of benchmark functions. A comprehensive comparative study shows the superiority of the proposed method compared to the original MPA and even other recent meta-heuristics. The paper also considers solving a real-world case study around power allocation in non-orthogonal multiple access (NOMA) and visible light communications (VLC) for Beyond 5G (B5G) networks to showcase the applicability of the NMPA algorithm. NMPA algorithm shows its superiority in solving a wide range of benchmark functions as well as obtaining fair power allocation for multiple users in NOMA-VLC-B5G systems compared with the state-of-the-art algorithms.
    • Sustainable transition towards biomass-based cement Industry: A review

      Kusuma, Ravi Teja; Hiremath, Rahul B.; Rajesh, Pachimatla; Kumar, Bimlesh; Renukappa, Suresh (Elsevier, 2022-05-02)
      Cement manufacturing is a hard-to-abate industrial sector that accounts for 5 to 8% of global anthropogenic emissions. Approximately 80 to 90% of these emissions occur during limestone calcination and fuel combustion processes. Decarbonising these two emission and energy-intensive processes requires a sustained and regenerative supply of low-carbon resources. Unlike other renewables such as solar or wind, biomass is uniquely positioned to abate emissions from fuel combustion and process emissions by substituting clinker with biomass ash. Moreover, bioenergy with carbon capture utilisation or storage offsets the energy penalties and associated emissions due to the deployment of carbon-capturing technologies. The sustainable transition towards biomass-based industry involves multifaceted socio-technical conflicts across bioenergy and cement sectors. This review uncovers opportunities, challenges and interplay involved in the sustainable transition of the cement industry through the lens of circular bioeconomy and multi-level perspective. The review found that 20 to 30% of fossil fuels can be replaced with biofuels without significant capital investments. This can be further enhanced through pre-processing of biomass and process optimisation. Clinker substitution with biomass ash is reported to be in the range of 3 to 80%. To increase the uptake of biomass, key aspects of circular bioeconomy are good starting points for transition at an organisation level, but system-wide change demands policy interventions. The policy intervention points presented in this study will serve as focus areas for practitioners and policy makers.
    • Spiderweb cellular structures manufactured via additive layer manufacturing for aerospace application

      Bari, Klaudio; Bollenbach, Lucie (MDPI, 2022-05-01)
      With increasing the energy costs and aiming for fossil-free Europe, cellular structures could provide a cost-effective tool for saving fuel consumption in aircraft. To achieve this goal, a cellular structure topology is a rapidly growing area of research facilitated by developments in additive layer manufacturing. These low-density structures are particularly promising for their aerospace applications. In this paper, four cellular structure topologies are developed to serve as a vibration damper in small electric aircraft motor, we have compared their performance with the original motor holder in the aircraft. This paper introduces the roadmap of scaffolding concept design and provides a novel concept in vibration damping. Based on the FEA simulation, aluminium 6061T spiderweb-inspired lattices (weight 0.3473 g and porosity 84%) have proven to have the lowest natural resonance and highest yield strength to weight ratio compared to other scaffolding concepts.
    • Academic LGBTQ+ terminology 1900-2021: Increasing variety, increasing inclusivity?

      Thelwall, Mike; Devonport, Tracey; Makita, Meiko; Russell, Kate (Routledge, 2022-04-27)
      LGBTQ+ labels and terminology in society embed ideological assumptions and affect who gains community support and protection. In academia, terminology is also needed to help define study objects, methods, and goals. Academics therefore need to choose their words to be both precise and appropriate, adjusting to changes in societal language. This article assesses the evolution of LGBTQ+ terminology in the titles and abstracts of academic journal articles since 1900 to identify the main trends. Based on a search of 74 LGBTQ+ terms in Scopus, LGBTQ+ related journal articles have almost continually increased in prevalence since 1900. In parallel, the concept of homosexuality that dominated early research has almost disappeared, being replaced by the word gay or more specific terms, such as lesbian or bisexual. Transexual terminology has also been supplanted by transgender and trans* terminology. At various points in time other LGBTQ+ terms have emerged with activist, health professional and academic origins. These include multiple acronyms, inclusive phrases, and activity-specific phrases (e.g., men who have sex with men) that are not used by the LGBTQ+ community. Currently, no terminologies are dominant, with this plurality probably reflecting differing research needs.
    • Critical barriers of using smart home technologies (SHTs) to the elderly in Hong Kong

      Wadu Mesthrige, Jayantha; Oladinrin, Olugbenga Timo; Ojo, Lekan Damilola (Taylor & Francis, 2022-04-23)
      Similar to other developed economies, Hong Kong also faces a severe ageing-related problems. Considering the ageing-in-place initiative to enhance the safe living of the elderly population in their familiar living environments, the use of SHTs has been proposed and employed. Meanwhile, there are challenges that may impede the purpose of developing SHTs by the elderly. Therefore, this paper investigated the barriers of SHTs to the elderly in Hong Kong, determined the critical ones and further categorized into manageable size. Based on the various analyses conducted, the characterization of the critical barriers of SHTs to the elderly in Hong Kong are cost and knowledge barrier, personal concern, and uncertainty barrier. The study provides recommendations to manufacturers of SHTs, the organisations where the senior adults worked before retirements, families of the elderly, the government and the seniors that could help to improve and enhance the ageing-in-place (AIP) in Hong Kong.
    • Crushing and energy absorption properties of additively manufactured concave thin-walled tubes

      Baroutaji, Ahmad; Arjunan, Arun; Singh, Gurpal; Robinson, John (Elsevier BV, 2022-04-22)
      Developing an innovative protective structure with excellent energy absorption performance is a continuous research effort. The emerging additive manufacturing techniques allow fabricating structures with complex geometrical shapes which have the potential to yield unprecedented energy absorption properties. Accordingly, in this paper, the crush and energy absorption behaviour of new designs, namely Concave Tubes (CTs) featuring inwardly curved sidewalls, is assessed experimentally and compared to that of Standard tubes (STs) featuring straight sidewalls. Tubes with different geometrical configurations, including concave circular (CC), concave square (CS), standard circular (SC), and standard square (SS), are fabricated using the Selective Laser Melting (SLM) process from AlSi10Mg aluminium powder and then crushed axially under quasi-static loading. It was found that the tubes have fractured and developed a splitting deformation mode, instead of progressive buckling, during the axial crushing resulting in relatively low energy absorption performance. The experimental results revealed superior energy absorption performance for the CTs over the STs. A Multi-Attribute Decision Making (MADM) technique known as Complex Proportional Assessment (COPRAS) is used to identify the best design. The COPRAS results show that the CC design is the best energy absorbing tube outperforming all other configurations presented in this paper.
    • I'm nervous about sharing this secret with you: YouTube influencers generate strong parasocial interactions by discussing personal issues

      Thelwall, Michael; Stuart, Emma; Mas-Bleda, Amalia; Makita, Meiko; Abdoli, Mahshid (National Science Library, the Chinese Academy of Sciences, 2022-04-20)
      Purpose: Performers may generate loyalty partly through eliciting illusory personal connections with their audience, parasocial relationships (PSRs), and individual illusory exchanges, parasocial interactions (PSIs). On social media, semi-PSIs are real but imbalanced exchanges with audiences, including through comments on influencers’ videos, and strong semi-PSIs are those that occur within PSRs. This article introduces and assesses an automatic method to detect videos with strong PSI potential. Design/methodology/approach: Strong semi-PSIs were hypothesized to occur when commenters used a variant of the pronoun ‘you’, typically addressing the influencer. Comments on the videos of UK female influencer channels were used to test whether the proportion of you pronoun comments could be an automated indicator of strong PSI potential, and to find factors associating with the strong PSI potential of influencer videos. The 117 highest and 117 lowest strong PSI potential videos were classified with content analysis for strong PSI potential and evidence of factors that might elicit PSIs. Findings: The you pronoun proportion was effective at indicating video strong PSI potential, the first automated method to detect any type of PSI. Gazing at the camera, head and shoulders framing, discussing personal issues, and focusing on the influencer associated with higher strong PSI potential for influencer videos. New social media factors found included requesting feedback and discussing the channel itself. Research limitations: Only one country, genre and social media platform was analysed. Practical implications: The method can be used to automatically detect YouTube videos with strong PSI potential, helping influencers to monitor their performance. Originality/value: This is the first automatic method to detect any aspect of PSI or PSR.
    • Germination of Triticum aestivum L.: Effects of soil–seed interaction on the growth of seedlings

      Chaichi, Mehrdad; Nemati, Ahmad; Dadrasi, Amir; Heydari, Moslem; Hassanisaadi, Mohadeseh; Yousefi, Ali Reza; Baldwin, Timothy; Mastinu, Andrea (MDPI, 2022-04-15)
      Seed size, sowing depth, and seed disinfection can affect seed germination and seedling establishment, which, in turn, can directly affect crop growth and yield. The current study was comprised of two experiments, the first of which was conducted in the laboratory, and a second which was performed under glasshouse conditions. The objective of these experiments was to investigate the effects of seed size, sowing depth, and seed disinfection on seed germination and initial seedling growth of selected wheat (Triticum aestivum L.) cultivars. The treatments in laboratory experiment were arranged in a completely randomized design, which included: (Ι) four wheat cultivars (Pishgam, Haydari, Soissons, and Mihan), (ΙΙ) two seed size classes (x &lt; 2.25 mm, and x &gt; 2.25 mm), and two disinfection treatments (no-disinfection and disinfection), (ΙΙΙ) with five replicates. In addition to the aforementioned treatments, the effect of planting depth (4, 6, and 8 cm) was also investigated in the subsequent glasshouse experiment. The best results were obtained at a sowing depth of 4 cm, in the non-disinfected treatment, using large seeds. In contrast, the lowest percentage and speed of seed germination and vigor index were observed in seeds sown at 8 cm depth, in the disinfected seed treatment, using small seeds. Large seeds contain larger nutrient stores which may improve seed germination indices, which would therefore result in improved percentage and speed of seed germination, followed by faster coleoptile and seedling growth, higher seedling dry weight and seed vigor. These data also illustrated that seed disinfection in the Pishgam and Haydari cultivars had inhibitory effects upon coleoptile growth and seedling length, which could be related to the fungicide’s chemical composition. Unlike other cultivars, disinfection did not show a significant effect on the Soissons cultivar. Based on our data, in order to improve both the speed of wheat seed germination and subsequent plant growth and development; it is necessary to select high-quality, large seeds, planted at a specific planting depth, which have been treated with an effective disinfectant; all of which will be specific for the wheat cultivar in question. Overall, the current study has provided useful information on the effect size seed, sowing depth, and disinfection have upon germination characteristics and seedling growth of wheat cultivars, which can form the basis for future field scale trails.
    • A review of the studies on CO₂–brine–rock interaction in geological storage process

      Peter, Ameh; Yang, Dongmin; Eshiet, Kenneth Imo-Imo Israel; Sheng, Yong (MDPI, 2022-04-12)
      CO2–brine–rock interaction impacts the behavior and efficiency of CO2 geological storage; a thorough understanding of these impacts is important. A lot of research in the past has considered the nature and impact of CO2–brine–rock interaction and much has been learned. Given that the solubility and rate of mineralization of CO2 in brine under reservoir conditions is slow, free and mobile, CO2 will be contained in the reservoir for a long time until the phase of CO2 evolves. A review of independent research indicates that the phase of CO2 affects the nature of CO2–brine–rock interaction. It is important to understand how different phases of CO2 that can be present in a reservoir affects CO2–brine–rock interaction. However, the impact of the phase of CO2 in a CO2–brine–rock interaction has not been given proper attention. This paper is a systematic review of relevant research on the impact of the phase of CO2 on the behavior and efficiency of CO2 geological storage, extending to long-term changes in CO2, brine, and rock properties; it articulates new knowledge on the effect of the phase of CO2 on CO2–brine–rock behavior in geosequestration sites and highlights areas for further development.
    • Heat flux and coolant concentration in hypersonic turbulent flow with transpiration cooling

      Cerminara, Adriano (UK Heat Transfer Conference, 2022-04-06)
      The present contribution shows results from direct numerical simulations (DNS) of a Mach 5 turbulent flow on a flat plate with modelled porous injection at different blowing ratios, representative of a transpiration-cooling system. It is found that the coolant film on the surface is preserved within the calmed region, whereas in the turbulent wedge it decays as a consequence of the wall-normal convective transport. This, in turn, results in the beneficial effect of the blowing ratio on the wall heat flux being relevant within the transitional region, but almost negligible within the turbulent wedge.
    • Reconsidering terms for mechanisms of polymer growth: The “Step-Growth” and “Chain-Growth” Dilemma

      Chan, Chin Han; Chen, Jiun-Tai; Farrell, Wesley S; Fellows, Christopher M; Keddie, Daniel J; Luscombe, Christine K; Matson, John B; Merna, Jan; Moad, Graeme; Russell, Gregory T; et al. (RSC, 2022-04-05)
      The terms “step-growth polymerization” and “chain-growth polymerization” are used widely in both written and oral communications to describe the two main mechanisms of polymer growth. As members of the Subcommittee on Polymer Terminology (SPT) in the Polymer Division of the International Union of Pure and Applied Chemistry (IUPAC), we are concerned that these terms are confusing because they do not describe the fundamental differences in the growth of polymers by these methods. For example, both polymerization methods are comprised of a series of steps, and both produce polymer chains. In an effort to recommend comprehensive terms, a 1994 IUPAC Recommendation from the then version of SPT suggested polycondensation and polyaddition as terms for the two variants of “step-growth polymerization”, and similarly chain polymerization and condensative chain polymerization for two variants of “chain-growth polymerization.” However, these terms also have shortcomings. Adding to the confusion, we have identified a wide variety of other terms that are used in textbooks for describing these basic methods of synthesizing polymers from monomers. Beyond these issues with “step-growth” and “chain-growth,” synthesis of polymers one monomer unit at a time presents a related dilemma in that this synthetic strategy is wholly encompassed by neither of the traditional growth mechanisms. One component of the mission of IUPAC is to develop tools for the clear communication of chemical knowledge around the world, of which recommending definitions for terms is an important element. Here we do not endorse specific terms or recommend new ones; instead, we aim to convey our concerns with the basic terms typically used for classifying methods of polymer synthesis, and in this context we welcome dialogue from the broader polymer community in a bid to resolve these issues.