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Identification and evaluation of structural heterogeneity in spent cathode materials is crucial to developing appropriate remediation strategies for novel recycling processes. Native heterogeneities may be exacerbated during the cell's operational lifetime, as sub-particle-scale variations induce anisotropic expansion and contraction upon cycling. Structural transformations resulting from repeated cycling and calendar aging predominantly occur at the secondary particle surface and at the grain boundaries (GBs) between primary particles. However, the diffusion and stress build up around and across GBs are poorly understood. In this study, electron backscatter diffraction (EBSD) is employed to track sub-grain lattice structure across a statistically relevant number of Li(Ni0.33Mn0.33Co0.33)O2 (NMC-111) particles. Specifically, differences in lattice misorientation – measured as the deviation from the grain's average orientation – are tracked as a function of position within the electrode (near current collector, middle, and near separator) and as a function of electrochemical cycling. Further, a novel method of structural analysis is developed, offering insight into sub-grain diffusion behavior by comparing lattice misorientation near the grain boundary versus in the grain bulk. The present results suggest that electrode-scale spatial heterogeneity in lattice structure is induced by initial manufacturing conditions, and that radial gradients in lattice misorientation evolve at the primary particle scale with repeated electrochemical cycling.

Dispositional capacity assessment, which evaluates a patient's ability for self-care after hospital discharge, is a novel concept with important implications for work in consultation-liaison, inpatient, and emergency psychiatric settings. In this Open Forum, the authors present an illustrative case, review literature relevant to dispositional capacity, and explore social theory that elucidates the concept. Psychiatrists are specifically positioned to provide leadership in this area. Psychiatrists should consider further developing and formalizing criteria for dispositional capacity assessment.

Submitted by Jonathan Sousa de Almeida (jonathan.sousa@ufma.br) on 2022-10-10T13:59:24Z No. of bitstreams: 1 DAVIDJOSEPHPEREIRABESERRA.pdf: 68212454 bytes, checksum: 971a1f80dc673734b7f93ef4c1e02e5f (MD5) Made available in DSpace on 2022-10-10T13:59:24Z (GMT). No. of bitstreams: 1 DAVIDJOSEPHPEREIRABESERRA.pdf: 68212454 bytes, checksum: 971a1f80dc673734b7f93ef4c1e02e5f (MD5) Previous issue date: 2022-09-27 CAPES Since synthesizing graphene in 2004, the search for modification in its properties, specialty the electronic one, has motivated the study of carbon allotropes with different symmetries that disrupt the graphene’s traditional honeycomb lattice. In addition to the geometric modifications, an efficient approach to tune the electronic properties of carbon-based materials is, since heteroatom insertion, to a complete system composed of another chemical species, like boron nitride, or simply BN. From a fundamental point of view, boron and nitrogen have deficiency and excess of one valence electron relative to carbon, and they have similar atomic radii. Here, a new carbon allotrope is proposed. It is named the naphthylene-γ, which is theoretically constructed by combining phenyl-like (P) and naphthyl-like (N) blocks joined by 4-membered links, resulting in a system with large 10- and 12-ring pores. Furthermore, the naphthylene-γ is suitable to be cast into a boron- nitride configuration since it is a bipartite structure featuring only even-membered rings. It turns out BN configurations of naphthylene-γ can potentially result in systems suitable to be embedded into nanoelectronics applications since they are expected to exhibit robust band gaps. With this motivation, several hybrid systems were hypothetically proposed by replacing part of naphthylene-γ’s C atoms for BN sectors with different concentrations. It was utilized first-principles calculations based on Density Functional Theory (DFT), implemented on the SIESTA code. The naphthylene-γ has a semiconductor behavior, and theory predicts that this property is shared by its nanoribbon counterparts. The computational analysis also indicates the electronic structure of these systems is dictated by quasi-1D states due to the interplay between the system’s geometry (e.g., chirality and edge structure) and its electronic properties. The energy gap for the hybrid γ systems does not vary monotonically with increasing BN concentration. In fact, strategical choices for the sites undergoing C-to-BN substitution result in specific modifications in the electronic signature of the systems. It was also investigated full-BN naphthylene-γ sheets, which show band gaps significantly different from those of hexagonal-BN. It further investigated nanoribbons based on these BN sheets, showing that they closely follow the properties of their parent 2D structure as they feature frontier states internally located over the ribbon structures. Desde a síntese do grafeno em 2004, a busca por modificações em suas propriedades, principalmente eletrônicas, tem motivado o estudo de formas alotrópicas de carbono que diferem da simetria hexagonal, característica do grafeno. Além de modificações geométricas, uma abordagem eficaz na modulação das propriedades eletrônicas de materiais baseados em carbono consiste, desde a inserção de heteroátomos, até a composição completa da estrutura por átomos de diferentes espécies químicas, como é o caso do uso do nitreto de boro (BN). Neste trabalho, propõe-se um novo alótropo de carbono chamado naphthylene- γ, o qual é conceitualmente composto pela fusão de unidades do tipo fenil e naftil através de anéis quadrados. Geometricamente, este sistema possui largos poros, compostos por 10 e 12 átomos. Além disso, o naphthylene-γ tem a característica de possuir apenas anéis com número par de átomos, formando uma estrutura bipartida, o que o torna adequado para ser construído em uma configuração com nitreto de boro. É de se esperar que tal sistema exiba um largo gap eletrônico, podendo ser empregado em nanoeletrônica. Devido às características interessantes apresentadas pelo naphthylene-γ, também foram propostos sistemas híbridos a partir da substituição dos átomos de carbono por BN, os quais compunham os blocos básicos de construção do naphthylene-γ, com diferentes concentrações. Com o objetivo de estudar o que se propõe, utilizou-se uma abordagem de primeiros princípios, baseados na Teoria do Funcional da Densidade, implementado no programa SIESTA. Observou-se que o naphthylene-γ é um semicondutor com gap eletrônico igual a 0,12 eV. Esta propriedade é compartilhada também por suas respectivas nanofitas, cuja estrutura eletrônica é regida por estados quasi-1D a depender da geometria dos sistemas (quiralidade e estrutura das bordas). Para os sistemas γ híbridos, observou- se que o gap eletrônico não varia monotonicamente com o aumento da concentração de BN. De fato, escolhas estratégicas para as unidades substituídas por BN resultam em modificiações específicas na assinatura eletrônica dos sistemas. Além disso, sistemas completamente compostos por BN também foram investigados, chamados γ-BN (I) e γ-BN (II), e apresentaram gaps eletrônicos consideravelmente diferentes do nitreto de boro hexagonal. Nanofitas baseadas nesses sistemas BN também foram investigadas e apresentaram propriedades semelhantes ao correspondente 2D, visto que seus estados de fronteira estão localizados internamente nas estruturas das nanofitas.

Aim: Anethum sowa L. isan aromatic plant with pharmacological potential. The chemical composition and the therapeutic of Anethum sowa L. herb oil grown in South Karnataka is very few; moreover, its essential oil and extract together is not being studied and compared for its effects on colon cancer cell lines HCT -116 and anti collagense study . Methods: The current investigation was intended to sight see the incidence of components present in the herb oil examined by (GC-MS), antioxidant , antimicrobial , anticancer & anticollagenase potential was investigated and further the insilco docking studies to unleash the potential drug like molecules in the therapeutic plant was studied . Results: 5-Oxo-4,5,6,7-tetrahydro-1H-pyrrolo[2,3-c]pyridine-3-propionic acid methyl ester, (17.41%),beta-Amyrin(8.20),ritodrine(6.49),1-Naphthalenol,decahydro-1,4a-dimethyl-7-(methylethylidene)-,[1R-(1.alpha.4a.beta,8a.alpha)](2.39%),meta-Cymene(1.95%),trans-z-alpha-Bisabolene epoxide (1.80), and Viridiflorol(0.77%) were the new compounds isolated from this therapeutic plant, and Anethum sowa L. herb ethanolic extract contained many potential phytochemicals. The total phenol and flavonoid of the herb extract were 0.136mg/ml. and 0.108mg/ml respectively . Anethum sowa L. herb extract ABTS antioxidant assay showed excellent activity with an IC50 of 540µg/ml which was in power with gallic acid which showed an IC 50 of 393µg/ml. Essential oil of Anethum sowa L. herb exhibited potent antimicrobial activity against all the three microorganisms E-coli strain (MTCC 433), Klebsiella pneumoniae strain (MTCC 3384) Streptococcusmutants strain (MTCC 497) with a minimum inhibitory concentration of 20% herb oil . Cytotoxicity of Anethum sowa L.herb essential oil and ethanolic extract against Colon cancer cell lines – HCT -116 , showed that herb oil and herb ethanolic extract repressed the cell growth of the cell . Herb oil with an IC50 79.75µg/ml was more effective than the herb extract . Herb essential oil showed the maximum capacity in inhibiting the collagenase when compared to ethanolic extract of herb, the percentage of inhibition of Anethum sowa L. herb essential oil was found to be 60.89% and that of herb extract was (15.18%). Conclusion: Herb oil showed very good anticancer, antimicrobial and anticollagenase activity and by the In silico docking performed between the compounds present in the herb oil, MAI-150 and APC of Homo sapiens, it was found that lupeol showed the highest binding affinity with APC when compared with MAI-150 and rest other compounds present in the herb oil.

Questions about purpose, life meaning, and life satisfaction drive central debates about what good education should look like in schools. This study compares adolescent purposes, life meaning, social support and life satisfaction in Singapore and Israel. Meaning in life refers to finding one’s significance; purpose uses this significance in ways beyond self. Key findings showed four purpose clusters for Singapore: no orientation, self-focused, other-focused, and both self- and other-focused. Israeli adolescents were in three purpose clusters without the no orientation group. Israeli adolescents had significantly higher life satisfaction, with no purpose orientation for 18% of Singapore’s students having significant negative impact on life satisfaction. Presence of meaning, parents’ support followed by teachers’ support were positive predictors of life satisfaction. Notably, Israeli students had more life meaning and parental support; Singapore’s adolescents had more teacher support but were searching for meaning. Implications for a more human experience of schooling are discussed.

International education achievement indicators potentially obscure students’ localised experiences of school. This paper examines adolescent purpose to understand what drives students’ learning exp...

Lithium-ion batteries (LIBs) have been the predominant energy storage technology for a variety of applications such as portable electronic devices and wireless power tools. However, the rising demand for emerging technologies such as long-range electric vehicles and grid-level energy storage and delivery has drastically increased the necessity for low-cost LIBs with enhanced performance and safety. Improvements in the modern LIB technology can be achieved through improvements in different, individual components of the battery. Among the key components of the battery, the separator plays a vital role. To date, polypropylene (PP)/polyethylene (PE) membranes have been used as separators in LIBs due to their desired electrochemical stability. However, these separator materials suffer from low thermal stability, which results in their deformation or decomposition at elevated temperatures upon high charging rates1. A dangerous consequence of this material degradation is an electrical short, leading to an aggressive discharge of the battery and subsequent fire. Moreover, PP/PE separators possess relatively low electrolyte wettability and an expensive and eco-unfriendly fabrication process. Hence, alternative separator materials for future LIB technology are indispensable. Among alternative separator materials, cellulose is a promising candidate2. Cellulose is derived from biomass which is one of the most abundant and renewable resources on Earth. It also is non-toxic and has high mechanical and chemical stability. Additionally, with an initial decomposition temperature of 270°C, cellulose offers a major advantage in thermal stability compared to its polymeric competitors3. The thermal and electrochemical stability, electrolyte wettability, and performance of cellulose-based separators in LIBs have been studied3,4. However, those reports mostly consider the conventional LIB electrode materials– Li transition metal oxide and graphite; and focus on the separator/electrolyte compatibility. Therefore, to be considered for future generations of high-performance Li-based batteries, cellulose-based separators must be investigated in batteries with new electrode chemistries. This work presents new insights on the interaction of cellulose-based separator and metallic Li – the leading candidate for future anodes. Coin cells were prepared using various cathode materials, Li metal anode, and a commercial cellulose-based separator. The cycling performance of the cells was tested at different C rates. Results were compared with the cycling performance of the coin cells with similar electrodes but a commercial PP/PE separator. Comparable discharge profiles were observed in the two groups of cells, but the cellulose separator hampered the charging process. Additional electrochemical analysis suggested an undesired interaction between the cellulose-based separator and metallic Li. To further understand this interaction, various protective coatings on the separator were investigated, the results of which suggest a mechanical degradation in the cellulose separator during cycling and consequently a soft short. These results are expected to provide a new understanding regarding the stability of cellulose-based separators in Li metal-containing batteries, which can help with their implementation in the next generation of Li-based batteries with enhanced performance and safety. References: Zhang, J.; Liu, Z.; Kong, Q.; Zhang, C.; Pang, S.; Yue, L.; Wang, X.; Yao, J.; Cui, G. Renewable and Superior Thermal-Resistant Cellulose-Based Composite Nonwoven as Lithium-Ion Battery Separator. ACS Appl. Mater. Interfaces 2012, 5, 1, 128-134. Yu, B.; Park, K.; Jang, J.; Goodenough, J. Cellulose-Based Porous Membrane for Suppressing Li Dendrite Formation in Lithium-Sulfur Battery. ACS Energy Lett. 2016, 1, 3, 633-637. Zhang, H.; Wang, X.; Liang, Y. Preparations and Characterization of a Lithium-ion Battery Separator from Cellulose Nanofibers. Heliyon, 2015, 1, 2, e00032. Sheng, J.; Tong, S.; He, Z.; Yang, R. Recent Developments of Cellulose Materials for Lithium-ion Battery Separators. Cellulose 2017, 24, 4103-4122.

3rd Pharmacoeconomics and Outcomes Research Virtual Conference 202121st – 23rd September 2021

Motion responses is a primary factor affecting the wave attenuation of floating breakwaters. This study aims at investigating the motion responses of a floating wave barrier (or known as H-Float) subjected to regular waves and a slack mooring using physical modelling. The motion reactions of the H-Float, which are empirically quantified by the response amplitude operators, RAOs for heave, surge and pitch, are related with the relative width and draft of the floating barrier as well as the wave steepness. The motion responses, particularly the surge and pitch, have been proven to significantly affect the wave attenuation of the breakwater. When subjected to slack mooring, the H-Float attains an optimum wave attenuation performance at a draft-to-water depth ratio of 0.13 regardless of the wave conditions.

Graphenylene and naphthylene have recently been proposed as two-dimensional carbon allotropes conceptually defined by the assembly of phenyl-like (P) or naphthyl-like (N) units with the creation of side squarelike rings. These structures can be cut into one-dimensional (1D) nanoribbons displaying electronic properties ranging from metals to semiconductors. Even though they have not been synthesized to date, recent advances in preprogrammed atomically precise chemical routes are compatible with their future synthesis. Here, an alternative naphthylene form is proposed. It is named as the $\ensuremath{\gamma}$ type, which is theoretically constructed by combining P and N blocks joined by 4-membered links. This naphthylene-$\ensuremath{\gamma}$ has a semiconductor behavior and theory predicts that this property is shared by its nanoribbon counterparts. Computational analysis also indicates the electronic structure of these systems is dictated by quasi-1D states due to the interplay between the system's geometry (e.g., chirality and edge structure) and its electronic properties.

Currently, there is a pandemic forcing social distancing and, consequently, traditional in-person education must shift to a virtual curriculum to protect all parties and continue professional development. Recognizing that not all emergency medicine (EM) content can be taught through a virtual platform, we propose a model for nearly all EM resident didactic conference adaptation to a virtual format to meet the needs of the adult learner while protecting all participants from the current coronavirus pandemic.

The ethical project of education hinges on the ideal of caring relations between teachers and students, an ideal that entails deep emotional commitments on the part of teachers. Drawing on interview data from a larger study of teachers’ lived experiences in Singapore’s secondary schools, this paper examines the cultural politics of caring as an emotional practice in teaching. The ethic of care serves to construct normative accounts of good teaching based on “feeling rules,” and becomes a disciplinary technology for evaluating the professional, social and emotional competencies of teachers. I suggest that this project in turn entails an ideological effort to mobilize teachers’ emotional attachment to this ethical ideal. The ethic of care shapes the subjectivities, beliefs, and practices of English teachers, particularly as they circulate through the neoliberal imperatives of educational accountability regimes.

The call for an expanded, critical and socially-constructed view of literacy in response to contemporary semiotic and technological developments is not new. However, an under investigated area relates to the impact and influence of new media in the teaching and learning of English to speakers of other languages (ESOL). Following an overview of some key terms and concepts in the fields of Multimodal Composition and Communication, we describe and critique a number of the multimodal elements in ESOL textbooks. Subsequently, we present a case for cultivating a ‘personal’ sense of semiotic awareness and illustrate this with a brief analysis of an ESOL teacher’s exploration of meaning making through digital storytelling. Finally, we end by listing several benefits of introducing multimodality into ESOL supporting the irreducible viewpoint that envisages teachers as designers of apt learning environments in contrast to the static and immutable realms of content- and skills-based language instruction.

This paper explores how a multimodal argument might take shape. Looking specifically at how students might conceive of a multimodal argument through their own digital literacy practices in design, ...

Purpose is an intention over the long-term to have an effect on the world that is both meaningful to oneself and to others. What are schools doing to help students use the knowledge and skills they...

Background The systems that help people with mental disorders in Malaysia include hospitals, primary care, traditional and religious systems, schools and colleges, employers, families and other community members. Aims To better understand collaboration between and within these systems and create a theoretical framework for system development. Method A total of 26 focus groups and 27 individual interviews were undertaken with patients, carers, psychiatric hospital staff, primary care and district hospital staff, religious and traditional healers, community leaders, non-governmental organisation workers, and school and college counsellors. Grounded theory methods were used to analyse the data and create a theory of collaboration. Results Three themes both defined and enabled collaboration: (a) collaborative behaviours; (b) motivation towards a common goal or value; and (c) autonomy. Three other enablers of collaboration were identified: (d) relatedness (for example trusting, understanding and caring about the other); (e) resources (competence, time, physical resources and opportunities); and (f) motivation for collaboration (weighing up the personal costs versus benefits of acting collaboratively). Conclusions The first three themes provided a definition of collaboration in this context: ‘two or more parties working together towards a common goal or value, while maintaining autonomy’. The main barriers to collaboration were lack of autonomy, relatedness, motivation and resources, together with the potential cost of acting collaboratively without reciprocation. Finding ways to change these structural, cultural and organisational features is likely to improve collaboration in this system and improve access to care and outcomes for patients.

Electrochemical dissolution is a process where a metal is dissolved via oxidation and can be controlled through electrolyte properties, electrolyte flow, and applied potential. Electrochemical dissolution is employed in many manufacturing applications such as electrochemical machining, electrochemical pickling, metal refining, metal surface finishing, etc. Most of these dissolution applications use a traditional metal-contact method (metal being dissolved is in direct contact with the anode); however, some applications will have phenomena that cause operational issues, safety issues, or damage to the dissolver components. These phenomena include (1) difficulty maintaining contact, (2) arcing/sparking[1] in a flammable environment, which occurs because of a build-up of oxide, or (3) overheating, which can cause melting during dissolution. To avoid unsafe or destructive phenomena, a solution-contact electrolytic dissolution (SCED) method (metal being dissolved is only in contact with electrolyte) can be employed. Here, a three-dimensional model is developed to simulate solution-contact electrolytic dissolution in a small-scale system for the first time. A representation of a small-scale SCED system is shown in Figure 1. This system takes place within a HNO3 solution and includes a Pt anode and cathode where water-splitting and hydrogen formation occur, respectively. The sample coupon (our target for dissolution) acts as a physical barrier, so hydrogen ions gather on the anode-side of the sample coupon, forming a positively charged region, while H+ ions are consumed on the cathode-side of the coupon, leaving a negatively charged region. This imbalance of charge, along with the potential profile that forms within the system when voltage is applied to the anode, drive reactions to occur on the surface of the sample coupon. The reactions include the ejection of a metal ion, Mν+, towards the negatively charged region, while H+ ions combine with the free e-s released from the metal dissolution reaction to form hydrogen gas. The model theory developed here is able to predict stray currents in the solution-phase, a useful design tool to avoid corrosion of other components within an electrochemical system. [2-3] Discussion over important phenomena that must be properly represented to simulate this electrolytic dissolution process will take place, including electrochemical species transport, local surface reaction rates (using Butler-Volmer kinetics), and electrodynamic potential. References [1] McGeough, J. A., Khayry, A. B. M., Munro, W., & Crookall, J. R. (1983). Theoretical and experimental investigation of the relative effects of spark erosion and electrochemical dissolution in electrochemical arc machining. CIRP Annals, 32(1), 113-118. [2] Wang, D., He, B., & Cao, W. (2019). Enhancement of the Localization Effect during Electrochemical Machining of Inconel 718 by Using an Alkaline Solution. Applied Sciences, 9(4), 690. [3] Wang, D., Zhu, Z., Bao, J., & Zhu, D. (2015). Reduction of stray corrosion by using iron coating in NaNO 3 solution during electrochemical machining. The International Journal of Advanced Manufacturing Technology, 76(5-8), 1365-1370. Figure 1. Representation of the local electrochemical reactions that take place in a small-scale SCED system. Figure 1

Automotive battery manufacturers are working to improve individual cell and overall pack design by increasing their performance, durability, and range, while reducing cost; and active material volume change is one of the more complex aspects that needs to be considered during this process. Designers try to control or mitigate the effects of volume change using a variety of methods: inserting foam layers into battery packs, programming specific charging algorithms, using multiple active materials, etc. However, designers must resort to extensive testing to fully develop these methods for each new battery design because of the complexity in measuring and understanding the links between active material volume change’s mechano-electrochemical effects on the electrode and cell level. A multi-scale modeling approach shows promise to comprehensively account for active material volume change. In the work shown here, a mechano-electrochemical model was employed [1-4] to explore mechano-electrochemical relationships: (1) understanding the effects of realistic mechanical behavior of each cell component including foam packaging, (2) understanding the effects of thermodynamically non-ideal volume change behavior, and (3) relative lithiation (thus, volume change) behavior for electrodes with multiple active materials (such as a silicon-graphite composite anode). The unique ties between active material voltage, active material volume, and N:P capacity ratio will be discussed as well. References T. R. Garrick, K. Higa, S.-L. Wu, Y. Dai, X. Huang, V. Srinivasan and J. W. Weidner, Journal of The Electrochemical Society, 164, E3592 (2017). T. R. Garrick, X. Huang, V. Srinivasan and J. W. Weidner, Journal of The Electrochemical Society, 164, E3552 (2017). T. R. Garrick, K. Kanneganti, X. Huang and J. W. Weidner, Journal of The Electrochemical Society, 161, E3297 (2014). D. J. Pereira, J. W. Weidner and T. R. Garrick, Journal of The Electrochemical Society, 166, A1251 (2019). D. J. Pereira, M. A. Fernandez, K. C. Streng, X. X. Hou, X. Gao, J. W. Weidner, and T. R. Garrick, Journal of The Electrochemical Society, 167, 080515 (2020).

Automotive battery manufacturers are working to improve individual cell and overall pack design by increasing their performance, durability, and range, while reducing cost and active material volume change is one of the more complex aspects that needs to be considered during this process. To improve the balance between cost, stability, performance, and volume change behavior, some cell designers have introduced the use of multiple active materials within the same composite electrode. For example, LiMn2O4 (LMO) and LiNi1/3Co1/3Mn1/3O2 (NMC) active materials are both included in cathodes to benefit from this balance. In anodes, some designers have included both silicon and graphite to maximize gravimetric capacity while maintaining a tolerable degree of volume expansion to prevent damage to the cell and pack structure. While the inclusion of multiple active materials can be used to better tune electrode performance, stability, and volume change for specific applications, the modeling of these electrodes is significantly more complicated. Previously, Albertus et. al developed a model to account for multiple active materials within the same positive electrode.(1) Their model took the concept of a pseudo-two dimensional Li-ion cell model and incorporated multiple pseudo second-dimensions, which correlates to the radial direction of a theoretical active material particle. Therefore, they could account for each active material separately, where previously, an average particle radius, average film resistance, and average equilibrium potential would be assumed for the total electrode. In the study shown here, we build upon this modeling concept by incorporating our previously developed mechano-electrochemical equations to account for active material volume change.(2-5) Figure 1 shows an example of equilibrium potentials for two anode active materials as a function of lithiation fraction. The difference between these equilibrium potentials will dictate the preferential lithiation of the materials, and thus, the rate at which each material undergoes lithiation-based volume change. This allows for the simulation of volume change in diffusion-governed (high rate) or kinetic-governed (low rate) charge and discharge.The relationships between anode/cathode capacity, electrode voltages, and active material volume will be discussed. References P. Albertus, J. Christensen and J. Newman, Journal of The Electrochemical Society, 156, A606 (2009). T. R. Garrick, K. Higa, S.-L. Wu, Y. Dai, X. Huang, V. Srinivasan and J. W. Weidner, Journal of The Electrochemical Society, 164, E3592 (2017). T. R. Garrick, X. Huang, V. Srinivasan and J. W. Weidner, Journal of The Electrochemical Society, 164, E3552 (2017). T. R. Garrick, K. Kanneganti, X. Huang and J. W. Weidner, Journal of The Electrochemical Society, 161, E3297 (2014). D. J. Pereira, J. W. Weidner and T. R. Garrick, Journal of The Electrochemical Society, 166, A1251 (2019). D. J. Pereira, M. A. Fernandez, K. C. Streng, X. X. Hou, X. Gao, J. W. Weidner, and T. R. Garrick, Journal of The Electrochemical Society, 167, 080515 (2020). Figure 1. Equilibrium potential as a function of lithiation fraction for two anode active materials. Figure 1

Automotive battery manufacturers are working to improve individual cell and overall pack design by increasing their performance, durability, and range, while reducing cost; and active material volume change is one of the more complex aspects that needs to be considered during this process. In the study presented here, thermodynamically non-ideal (non-linear), lithiation-based volume change behavior for the anode and cathode active materials were incorporated into a previously developed mechano-electrochemical model.(1-4) Before, an ideal (linear) relationship between active material volume change and state-of-lithiation was assumed. Using the non-ideal active material volume change behavior, the changing thickness of an automotive relevant, large-format pouch cell was predicted while simulating cell discharge. Measurements were taken using an experimental setup capable of simultaneous mechanical and electrochemical operation and observation. Figure 1 shows that the mechano-electrochemical measurements prove to agree well with simulation when using non-ideal lithiation-based volume change as opposed to the previously assumed ideal volume change behavior. The resulting model was used to simulate other mechano-electrochemical phenomena including the effects of anode/cathode capacity ratio and changing pressure/porosity during cell discharge. This mechano-electrochemical model shows promise to help define operational parameters to mitigate negative effects from active material volume change and may act as a tool for developers to reduce the extensive electrochemical and mechanical testing required for the design of promising new batteries. References T. R. Garrick, K. Higa, S.-L. Wu, Y. Dai, X. Huang, V. Srinivasan and J. W. Weidner, Journal of The Electrochemical Society, 164, E3592 (2017). T. R. Garrick, X. Huang, V. Srinivasan and J. W. Weidner, Journal of The Electrochemical Society, 164, E3552 (2017). T. R. Garrick, K. Kanneganti, X. Huang and J. W. Weidner, Journal of The Electrochemical Society, 161, E3297 (2014). D. J. Pereira, J. W. Weidner and T. R. Garrick, Journal of The Electrochemical Society, 166, A1251 (2019). D. J. Pereira, M. A. Fernandez, K. C. Streng, X. X. Hou, X. Gao, J. W. Weidner, and T. R. Garrick, Journal of The Electrochemical Society, 167, 080515 (2020). Figure 1. Experimentally measured data and simulations using ideal and non-ideal active material volume change behavior for a NMC/LMO:Graphite pouch cell strain as a function of cell state-of-charge. Figure 1

Lithium-silicon chemistries show promise to increase battery capacity; however, silicon expands significantly during lithium intercalation, leading to inaccessible capacities as well as cell or pack failure due to pressure generation. Silicon-graphite (Si/C) composite anodes are used to increase the anode capacity while maintaining a tolerable degree of active material volume expansion. Recently, Dash and Pannala modeled anodes with increasing Si/C ratios and explored the tradeoff between increasing gravimetric capacity and the increasing active material volume expansion upon Li intercalation [1]. Their conclusion highlights that while the gravimetric capacity increases, there is ultimately a “threshold value” where the volumetric capacity will begin to decrease to account for the significant silicon volume expansion. This concept was built upon to account for electrochemical and mechanical design limitations applicable to battery packs for electric vehicles (EVs). We propose that increasing the Si/C ratio does not directly lead to an increase in the accessible capacity, because excessive volume expansion can lead to unacceptable cell pressure or electrode porosity. In order to predict the accessible capacity as a function of Si/C ratio, we integrated mechanical behavior for each individual cell component (e.g., composite anode, cathode, and foam packing) into our previous battery model [2-4]. This model can predict the split between changes in electrode porosity and dimensions by coupling component mechanical behavior to the volume change governed by electrochemical phenomena. In this presentation, we will focus on how the Si/C ratio will impact both mechanical and electrochemical behavior using our mechano-electrochemical model. Figure 1 shows an example of the pressure generation seen when considering (a) foam packaging and (b) a rigid volume for cells with varying percentages of Si in the anode. Accessible capacities of these materials can then be determined for a specific design’s pressure cutoff. Preliminary modeling of the links between active material Eeq, anode/cathode capacity balance, and volume change will also be discussed. References [1] R. Dash, and S. Pannala, Theoretical Limits of Energy Density in Silicon-Carbon Composite Anode Based Lithium Ion Batteries. Sci. Rep. 6, 27449; doi: 10.1038/srep27449 (2016). [2] T. R. Garrick, K. Kanneganti, X. Huang, and J. W. Weidner, “ Modeling Volume Change due to Intercalation into Porous Electrodes”, Electrochem. Soc. 2014 volume 161, issue 8, E3297-E3301 (2014). [3] T. R. Garrick, X. Huang, V. Srinivasan, and J. W. Weidner,”Modeling Volume Change in Dual Insertion Electrodes”, J. Electrochem. Soc. 2017 volume 164, issue 11, E3552-E3558 (2017). [4] T. R. Garrick, K. Higa, S. Wu, Y. Dai, X. Huang, V. Srinivasan, and J. W. Weidner, “Modeling Battery Performance Due to Intercalation Driven Volume Change in Porous Electrodes”, J. Electrochem. Soc. 2017 volume 164, issue 11, E3592-E3597 (2017). [5] D. J. Pereira, J. W. Weidner, and T. R. Garrick, "The Effect of Volume Change on the Accessible Capacities of Porous Silicon-Graphite Composite Anodes", J. Electrochem. Soc. 2019. Volume 166, issue 6, A1251-A1256 [6] D. J. Pereira, M. A. Fernandez, K. C. Streng, X. X. Hou, X. Gao, J. W. Weidner, and T. R. Garrick, "Accounting for Non-ideal, Lithiation-Based Active Material Volume Change in Mechano-Electrochemical Pouch Cell Simulation", Journal of The Electrochemical Society, 167, 080515 (2020). Figure 1. Cell pressure as a function of τ for a cell within (a) foam packing or (b) a fixed volume with an initial anode porosity of 0.37. Solid and dashed curves represent incremental 5% increases in silicon composition in the Si/C composite, from 0% to 25%. The solid horizontal lines represent pressure limitations of 250 kPa and 500 kPa. Figure 1

Automotive battery manufacturers are working to improve individual cell and overall pack design by increasing their safety, performance, durability, and range, while reducing cost; and active material volume change is one of the more complex aspects that needs to be considered during this process. In the study shown here, thermodynamically non-ideal, lithiation-based volume change behavior for the anode and cathode active materials were incorporated into a previously developed mechano-electrochemical model. The changing thickness of an automotive-relevant, large-format pouch cell was predicted while simulating cell discharge. Measurements were taken using an experimental setup capable of simultaneous mechanical and electrochemical operation and observation. The electrochemical and mechanical measurements prove to agree well with simulation when using non-ideal lithiation-based volume change as opposed to the previously assumed ideal volume change behavior. The resulting model was used to simulate other mechano-electrochemical phenomena including the effects of anode/cathode capacity ratio and changing pressure/porosity during cell discharge. This mechano-electrochemical model shows promise to help define operational parameters to mitigate negative effects from active material volume change and may act as a tool for developers reduce the extensive electrochemical and mechanical testing required for the design of promising new batteries.

Breakwaters are used to suppress the energy of waves for providing shelter to coastal and offshore facilities. Very often, the conventional rubble mound breakwaters result in high construction cost and several environmental problems, such as water contamination and wave amplification in front of the structures due to severe wave reflection. One way to alleviate the above-mentioned problem is to appropriately increase the porosity of the breakwaters. This paper aims at developing the optimum design of a porous box-type breakwater comprising multiple scrapped pipelines via physical modelling approach. Herein, the best geometrical design of the breakwater under the governing factors of porosity, width and internal tube length is proposed. A series of experiments have been conducted under the influence of regular wave environment through the analysis of wave transmission, reflection and energy loss. Several geometrical design criteria were derived to maximize the hydraulic performance of the breakwater, when adopted at sites. The proposed breakwater is a reasonably good wave attenuator and anti-reflection structure as well as an effective energy dissipator.

This is the final draft, after peer-review, of a manuscript published in Pedagogies: An International Journal. The published version is available online at http://dx.doi.org/10.1080/1554480X.2015.1066542

Most current production electric vehicles (EVs) contain cells within a battery pack or module in order to maintain electrical conductivity, prevent fatigue due to vibrations, and provide efficient cooling. Modules may contain cooling fins, thermistors, foam separators, and repeating frame elements to hold the cells. As the cells expand and contract during cycling, the stresses generated can cause the materials in the battery module to deform and crack. This fatigue can result in a loss of electrical or thermal contact and therefore, decreased range, reduced battery life or loss of function, or a loss of heat transfer fluid which could result in electrical shorts. Therefore, it is critical to properly design modules and packs to properly account for the volume change inherent in these pouch cells. Currently, empirical mechanical data is used to predict the thickness changes of cells with varying electrode porosities, chemistries, and thicknesses. The ability to relate electrode expansion to electrochemical operation and accurately predict cell volume change would save significant time in experimental efforts as well as material costs. Previously, our group developed a coupled electrochemical and mechanical model that accurately predicts the split between electrode porosity and dimensional changes [1-3]. Here, we employ our model along with lithiation-based particle expansion data for graphite [4], lithium nickel-manganese-cobalt oxide (NMC) [5], and lithium manganese oxide (LMO) [5], to predict the thickness change of a large-format pouch cell used in automotive battery packs. Then, we measured the thickness of the cell as the cell was discharged from .99 to .01 state-of-charge. Figure 1 shows the predicted anode and cathode strain compared to the measured cell displacement divided by the sum of the anode and cathode thicknesses. This method allows battery pack designers to appropriately account for new cell types using electrochemical performance and individual particle-level expansion parameters as inputs. Design considerations, as well as cell level volume changes will be discussed. References [1] T. R. Garrick, K. Kanneganti, X. Huang, and J. W. Weidner, “ Modeling Volume Change due to Intercalation into Porous Electrodes”, Electrochem. Soc. 2014 volume 161, issue 8, E3297-E3301 (2014). [2] T. R. Garrick, X. Huang, V. Srinivasan, and J. W. Weidner,”Modeling Volume Change in Dual Insertion Electrodes”, J. Electrochem. Soc. 2017 volume 164, issue 11, E3552-E3558 (2017). [3] T. R. Garrick, K. Higa, S. Wu, Y. Dai, X. Huang, V. Srinivasan, and J. W. Weidner, “Modeling Battery Performance Due to Intercalation Driven Volume Change in Porous Electrodes”, J. Electrochem. Soc. 2017 volume 164, issue 11, E3592-E3597 (2017). [4] Louli, A. J., et al. "Volume, pressure and thickness evolution of Li-ion pouch cells with silicon-composite negative electrodes." Journal of The Electrochemical Society 164.12 (2017): A2689-A2696. [5] Nam, Kyung-Wan, et al. "In situ X-ray diffraction studies of mixed LiMn2O4–LiNi1/3Co1/3Mn1/3O2 composite cathode in Li-ion cells during charge–discharge cycling." Journal of Power Sources 192.2 (2009): 652-659. [6] D. J. Pereira, J. W. Weidner, and T. R. Garrick, "The Effect of Volume Change on the Accessible Capacities of Porous Silicon-Graphite Composite Anodes." J. Electrochem. Soc. 2019 Volume 166, issue 6, A1251-A1256 Figure 1

Direct water electrolysis is commercially viable but too inefficient for large-scale hydrogen production. Hence the interest in using thermochemical cycles for producing hydrogen from renewable energy [1]. Thermochemical cycles produce hydrogen through a series of chemical reactions that result in the splitting of water at much lower temperatures (~500-1000ºC) than direct thermal dissociation (>2500oC). All other chemical species in these reactions are recycled resulting in the consumption of only heat and water to produce hydrogen and oxygen. Since water rather than hydrocarbons are used as the source of hydrogen in these thermochemical cycles, no carbon dioxide emissions are produced and the hydrogen is highly pure. Although there are hundreds of possible thermochemical cycles, the hybrid-sulfur (HyS) process is the only practical, all-fluid, two-step thermochemical cycle [2-5]. The high temperature step (850-950°C) involves the decomposition of H2SO4 to produce oxygen and sulfur dioxide via the following reaction: H2SO4 => SO2 + ½ O2 + H2O [1] The SO2 is separated, cooled, and sent to the SO2-depolarized electrolyzer (SDE). The resulting reactions at the anode and cathode, respectively, are: SO2 + 2H2O => H2SO4 + 2H+ + 2e- U0 SO2 = 0.158 V vs. SHE [2] 2H+ + 2e- => H2 U0 H2 = 0 V vs. SHE [3] Thus, the overall reaction in the electrolyzer is represented as: SO2 + 2H2O => H2SO4 + H2 [4] Considerable progress was made in the last decade in lowering the operating voltage and increasing the current density of the SDE by moving from a microporous rubber diaphragm separator used by Westinghouse [6] to a perfluorinated sulfonic acid membrane (e.g., DuPont’s Nafion®) [7-10]. For example, Westinghouse was only able to get the cell voltage down to 1.0 V at 400 mA/cm2, where we achieved 500 mA/cm2 at 0.71 V and 1.2 A/cm2 at 1.0 V using Nafion 212 (N212). However, to achieve overall process efficiency, concentrated sulfuric acid as well as low cell voltage at high current densities are necessary. The key issue when using membranes like Nafion that rely on water for their proton conductivity is that high acid concentrations dehydrate the membrane and dramatically increase membrane resistance. Therefore, we have recently developed an electrolyzer that uses sulfuric acid-doped polybenzimidazole (s-PBI) membranes as an alternative to membranes like Nafion because they do not rely on water for their proton conductivity [3, 11-14]. Here, we analyze the voltage losses and acid concentration from an SDE operated using s-PBI membranes under a range of operating conditions. From the voltage data and thermodynamic modeling, kinetic parameters and membrane conductivity were obtained to better understand and quantify the individual potential contributions to the cell voltage. The measured acid concentrations were also compared to predictions from water balances coupled to a non-ideal vapor-liquid equation of state. The physical parameters obtained here enable the prediction of cell voltage and acid concentrations over a wide range of operating temperatures, pressures, currents and reactant flow rates. References Nuclear Hydrogen Research and Development Plan, Department of Energy, Office of Nuclear Energy, Science and Technology (2004). C. Corgnale and W. A. Summers, Int J Hydrogen Energ, 36, 11604 (2011). J. W. Weidner, J Appl Electrochem, 46, 829 (2016). C. Corgnale, S. Shimpalee, M. B. Gorensek, P. Satjaritanun, J. W. Weidner and W. A. Summers, Int J Hydrogen Energ (2017). M. B. Gorensek and W. A. Summers, Int J Hydrogen Energ, 34, 4097 (2009). P. W. T. Lu, E. R. Garcia and R. L. Ammon, J Appl Electrochem, 11, 347 (1981). Staser, R. P. Ramasamy, P. Sivasubramanian and J. W. Weidner, Electrochem Solid St, 10, E17 (2007). J. A. Staser, M. B. Gorensek and J. W. Weidner, J Electrochem Soc, 157, B952 (2010). J. A. Staser and J. W. Weidner, J Electrochem Soc, 156, B16 (2009). J. A. Staser and J. W. Weidner, J Electrochem Soc, 156, B836 (2009). J. V. Jayakumar, A. Gulledge, J. A. Staser, C. H. Kim, B. C. Benicewicz and J. W. Weidner, Ecs Electrochem Lett, 1, F44 (2012). T. R. Garrick, A. Gulledge, J. A. Staser, B. Benicewicz and J. W. Weidner, ECS Transactions, 61, 11 (2014). T. R. Garrick, A. Gulledge, J. A. Staser, B. Benicewicz and J. W. Weidner, ECS Transactions, 66, 31 (2015). T. R. Garrick, C. H. Wilkins, A. T. Pingitore, J. Mehlhoff, A. Gulledge, B. C. Benciwicz, and J. W. Weidner, J. Electrochem. Soc., 164(14), F1591-F1595 (2017).

In their dealings with citizens, police in most jurisdictions across the country are prohibited from using unnecessary force, abusing their authority, discourteous behavior, and offensive language. This study examines the factors that contribute to citizens' judgments of fair punishment for police misconduct. Using a factorial survey, citizens are asked to judge vignettes of police misconduct that describe encounters between officers and civilians in detail. The findings show that citizens do weigh the officer's behavior, particularly the unnecessary use of