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Ice accumulation on aircraft surfaces poses significant safety and performance risks, necessitating the development of coatings to prevent ice adhesion. The present work focuses on characterizing the interfacial properties of ice on various substrates through molecular descriptors. We follow the hypothesis that has been previously proposed in several experimental works according to which a disordered, quasi-liquid layer (QLL) of water at the substrate/ice interface is developed, which in turn acts as a self-lubricant reducing material’s ice adhesion strength. To put this idea into the test, we conducted extensive molecular dynamics (MD) simulations on ice supported by different types of substrates, such as graphite, boron nitride, and a cross-linked epoxy polymer. Our findings reveal that the ice structure becomes disordered near the interface for all substrates, with a more pronounced effect in the polymer substrate. The formation of QLL at the interface was quantified using metrics such as local density, Q6order parameter, and hydrogen bonding. The polymer substrate showed a thicker QLL compared to the two flat surfaces, as this was verified by both the significant differences in the local water density profiles and the distribution of the employed order parameter. The latter ones were directly correlated to the development of hydrogen bonds between the interfacial water molecules and the polymer substrate’s polar atoms, which was found to induce a more intense disruption of ice’s crystal structure. Moreover, our analysis revealed that the polymer’s oxygen atoms contribute more to hydrogen bonding with the water molecules than the nitrogen atoms, with hydroxyl oxygens (−OH) contributing more compared to the epoxy ones (−O−). The analysis related to the dynamics of the interfacial water molecules revealed a substantial reduction in mobility on the epoxy, exceeding the slowdown observed on boron nitride, with graphite demonstrating the least reduction in dynamic behavior among the substrates studied.

Multiprincipal-element alloys are an enabling class of materials owing to their impressive mechanical and oxidation-resistant properties, especially in extreme environments1,2. Here we develop a new oxide-dispersion-strengthened NiCoCr-based alloy using a model-driven alloy design approach and laser-based additive manufacturing. This oxide-dispersion-strengthened alloy, called GRX-810, uses laser powder bed fusion to disperse nanoscale Y2O3particles throughout the microstructure without the use of resource-intensive processing steps such as mechanical or in situ alloying3,4. We show the successful incorporation and dispersion of nanoscale oxides throughout the GRX-810 build volume via high-resolution characterization of its microstructure. The mechanical results of GRX-810 show a twofold improvement in strength, over 1,000-fold better creep performance and twofold improvement in oxidation resistance compared with the traditional polycrystalline wrought Ni-based alloys used extensively in additive manufacturing at 1,093 °C5,6. The success of this alloy highlights how model-driven alloy designs can provide superior compositions using far fewer resources compared with the ‘trial-and-error’ methods of the past. These results showcase how future alloy development that leverages dispersion strengthening combined with additive manufacturing processing can accelerate the discovery of revolutionary materials.

Nonaqueous Li–O2batteries have the potential to aid in the electrification of our society due to their relatively high theoretical energy density. Unfortunately, the technology suffers from large degrees of irreversibility due to the aggressive chemical environment associated with the oxidation of the discharge product lithium peroxide. Herein, we present a study of a range of linear and cyclic amides and ureas as aprotic electrolyte solvents for the Li–O2battery, some of which show slight increases in reversibility relative to the well-established pseudo-stable glymes, although we find that none provide reversibility necessary to enable a rechargeable system. Using quantitative differential electrochemical mass spectrometry, acid titrations, and isotopic labeling of O2and carbon in the positive electrode, we provide insight into the degradation pathways for these solvents. In the companion article, we compare our experimental results presented here to solvent decomposition pathways including a Baeyer–Villiger oxidation mechanism.

The article "Careers: Why all the fuss about (Key)words?" by John Lawson discusses the importance of words, particularly keywords, in shaping career success in 2025. Words hold immense power in job searches, professional networking, and AI interactions, influencing perceptions and creating opportunities. Leveraging the right keywords in resumes, LinkedIn profiles, and job applications can significantly boost visibility and improve chances of success in a competitive job market. The article emphasizes the role of words in shaping perceptions, driving career success, unlocking AI's potential, reflecting leadership and emotional intelligence, and creating and controlling narratives in personal branding. As technology continues to shape job searching, strategic keyword usage is becoming increasingly crucial for visibility and opportunity in the future job market. [Extracted from the article]

Shape memory alloys have found wide-spread use in aerospace, automotive, biomedical, and commercial applications owing to their favorable properties and ease of operation. Binary NiTi, in particular, is known for its remarkable shape memory properties, mechanical strength, ductility, corrosion resistance, and biocompatibility. These properties can be further enhanced and better controlled through alloying NiTi with ternary, quaternary, and higher-order elements. Recently, researchers at NASA have compiled an extensive database of shape memory properties of materials, including over 8000 multi-component Ni–Ti alloys containing 37 different alloying elements. Using the Ni–Ti dataset, we train machine learning models to explore shape memory behavior of Ni–Ti alloys over a large compositional and processing space. The models predict transformation temperatures, hysteresis, and transformation strain, with low mean absolute errors of 14.8 °C, 7.2 °C, and 0.36%, respectively. We use these models to map trends and learn relationships between shape memory behavior and different parameters in the input design space. They can be used to make predictions for any multi-component alloy, without need for additional training. The combination of an extensive experimental dataset and accurate learning models, together, make our approach highly suitable for the discovery and design of new alloys with targeted properties.

As revenue growth for not-for-profit healthcare organizations continues to slow in these challenging times, philanthropic fundraising will be an increasingly crucial part of these hospitals' efforts to maximize their revenue [...]

However, to recast the words from Jack Nicholson's character in 'A Few Good Men,' all Marines rise and sleep under the blanket of discipline that drill provides. Even for those [...]

An interview with John Lawson, founder of Lawson Williams Consulting Group is presented. He discusses the challenges and opportunities presented by Industry 4.0, emphasizing the importance of asking the right questions amidst constant technological change. He highlights insights from the recent NZIFST conference, where speakers from Fonterra addressed the role of AI (artificial intelligence) in business.

The structure of interfacial water near suspended graphene electrodes in contact with aqueous solutions of Na2SO4, NH4Cl, and (NH4)2SO4has been studied using confocal Raman spectroscopy, sum frequency vibrational spectroscopy, and Kelvin probe force microscopy. SO42–anions were found to preferentially accumulate near the interface at an open circuit potential (OCP), creating an electrical field that orients water molecules below the interface, as revealed by the increased intensity of the O–H stretching peak of H-bonded water. No such increase is observed with NH4Cl at the OCP. The intensity of the dangling O–H bond stretching peak however remains largely unchanged. The degree of orientation of the water molecules as well as the electrical double layer strength increased further when positive voltages are applied. Negative voltages on the other hand produced only small changes in the intensity of the H-bonded water peaks but affected the intensity and frequency of dangling O–H bond peaks. The TOC figure is an oversimplified representation of the system in this work.

Preeclampsia does not appear to be caused by excessive oxidation of fats, according to researchers who measured levels of a specific free radical in urine samples from 29 pregnant women with preeclampsia. Preeclampsia is a serious complication of pregnancy.

The development of robust, high-performance integrated circuits (ICs) will enable numerous potential NASA missions of current interest, including long-duration robotic missions exploring the 460°C surface of Venus. Currently, NASA is looking towards SiC-based devices to provide such a solution. However, the current NASA silicon carbide (SiC) JFET device with a channel length of 6 μm (recently fabricated Gen. 11 ICs) limits mission-relevant circuit capabilities. In this study, we combined experiments with simulations to explore two straightforward fabrication strategies (shallow n−and extended n+) to reduce the SiC JFET channel length while maintaining the turn-off behavior needed to realize 500°C circuit operation. COMSOL Multiphysics was used to simulate the transfer characteristics and maximum potential below the gate of a 4H-SiC nJFET at 500°C, and a 1 μm gate length nJFET with turn-off performance comparable to the state-of-the-art is suggested.

In this work, coarse-grained (CG) models for two different sets of ionic liquids were developed from atomistic molecular dynamics (MD) reference systems, expanding their system size and time duration capabilities. The bonded force field of the CG systems was built using harmonic oscillator potential (HOP) fitting, while the nonbonded force field was generated with the multiscale coarse-graining (MS-CG) approach based on force matching. The dynamics of each system were corrected using the probability distribution function-based coarse-grained molecular dynamics (PDF-based CGMD) method. The structure and dynamics of each system were proven to match reference system data at two temperature scales. CG models and force fields for these liquids were developed to exemplify a general purpose methodology for producing MD results of ionic liquids and other fluids with accurate structural as well as dynamic properties. As an application, developed ionic liquids CG models were then applied to study vacuum–interface interaction. Density profile results of vacuum–interface exposure show significant deviation from bulk behavior. At the interface, multilayer ordering of ionic liquids is predicted to be similar to those observed from an experimental work. This ordering is intensified by decreasing temperature and use of the PDF-based CGMD method as opposed to conventional CG methods.

Since low back pain causes a huge number of accidents among workers and consumes one-third of all compensation benefits, it is important for all management concerned to follow a standard set of guidelines regarding this matter. A professional seminar organized by a prominent range of providers, corporate administrators and other experts has come up with the most updated checklist possible. It utilizes a 'sports medicine' approach and has recommendations on virtually every aspect of this problem. The proper application of these policies may well prevent aggravated back disabilities.

This article, titled "Careers: Building your Psychological Capital," discusses the importance of developing psychological capital in order to navigate the complexities of the job market and ensure long-term success and fulfillment. Psychological capital, which includes resilience and confidence, has become increasingly important due to rapid technological advancements and economic fluctuations. The article provides strategies for building confidence, such as reflecting on past achievements, setting realistic goals, acquiring new skills, seeking feedback, and building a supportive network. It also emphasizes the importance of maintaining and expanding career capital through lifelong learning, networking, seeking feedback, and being open to change. The article concludes by highlighting the need for professionals to possess both technical skills and psychological fortitude in order to thrive in their careers. [Extracted from the article]

The article focuses on the challenges faced by companies in recruiting food technologists amidst a skills-short market, highlighting the demand for experienced professionals and the struggle of graduates to gain relevant experience. Topics include the reasons behind the skills shortage, strategies for employers to attract and retain talent, and advice for graduates to enhance their employability through industry involvement and flexibility in job choices.

Recent experimental and computational evidence indicates that singlet oxygen (1O2) attacks the ethylene group (−CH2–CH2−) in ethylene carbonate (EC) leading to degradation in Li-ion batteries employing EC as the electrolyte solvent [J. Phys. Chem. A2018, 122, 8828-8839]. Here, we employ computational quantum chemistry to explore this mechanism in detail for a large set of organic molecules. Benchmark calculations comparing density functional theory to the complete active space second-order perturbation theory and internally contracted multireference configuration interaction indicate that the M11 functional adequately captures trends in the transition-state energies for this mechanism. Based on our results, we recommend that solvents which include the ethylene group should be avoided in Li-ion and Li–O2batteries where 1O2is generated unless neighboring functional groups raise the reaction barrier to avoid this decomposition pathway.

IMPORTANCE: Efficacy of cannabidiol has been demonstrated in seizures associated with Lennox-Gastaut and Dravet syndromes but appears not yet to have been established in conditions with primarily focal seizures, such as tuberous sclerosis complex (TSC). OBJECTIVE: To evaluate efficacy and safety of 25-mg/kg/day and 50-mg/kg/day cannabidiol dosages vs placebo against seizures associated with TSC. DESIGN, SETTING, AND PARTICIPANTS: This double-blind, placebo-controlled randomized clinical trial (GWPCARE6) enrolled patients between April 6, 2016, and October 4, 2018; follow-up was completed on February 15, 2019. The trial was conducted at 46 sites in Australia, Poland, Spain, the Netherlands, United Kingdom, and United States. Eligible patients (aged 1-65 years) were those with a clinical diagnosis of TSC and medication-resistant epilepsy who had had at least 8 TSC-associated seizures during the 4-week baseline period, with at least 1 seizure occurring in at least 3 of the 4 weeks, and were currently taking at least 1 antiepileptic medication. INTERVENTIONS: Patients received oral cannabidiol at 25 mg/kg/day (CBD25) or 50 mg/kg/day (CBD50) or a matched placebo for 16 weeks. MAIN OUTCOMES AND MEASURES: The prespecified primary outcome was the change from baseline in number of TSC-associated seizures for cannabidiol vs placebo during the treatment period. RESULTS: Of 255 patients screened for eligibility, 31 were excluded and 224 were randomized. Of the 224 included patients (median [range] age, 11.4 [1.1-56.8] years; 93 female patients [41.5%]), 75 were randomized to CBD25, 73 to CBD50, and 76 to placebo, with 201 completing treatment. The percentage reduction from baseline in the type of seizures considered the primary end point was 48.6% (95% CI, 40.4%-55.8%) for the CBD25 group, 47.5% (95% CI, 39.0%-54.8%) for the CBD50 group, and 26.5% (95% CI, 14.9%-36.5%) for the placebo group; the percentage reduction from placebo was 30.1% (95% CI, 13.9%-43.3%; P < .001) for the CBD25 group and 28.5% (95% CI, 11.9%-42.0%; nominal P = .002) for the CBD50 group. The most common adverse events were diarrhea (placebo group, 19 [25%]; CBD25 group, 23 [31%]; CBD50 group, 41 [56%]) and somnolence (placebo group, 7 [9%]; CBD25 group, 10 [13%]; CBD50 group, 19 [26%]), which occurred more frequently with cannabidiol than placebo. Eight patients in CBD25 group, 10 in CBD50 group, and 2 in the placebo group discontinued treatment because of adverse events. Twenty-eight patients taking cannabidiol (18.9%) had elevated liver transaminase levels vs none taking placebo. CONCLUSIONS AND RELEVANCE: Cannabidiol significantly reduced TSC-associated seizures compared with placebo. The 25-mg/kg/day dosage had a better safety profile than the 50-mg/kg/day dosage. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT02544763

Nitrate-based molten salts have been the most stable electrolytes in Li–O2electrochemical systems. While the high temperature of operation is a disadvantage, the molten-salt electrolytes offer a compelling inorganic alternative to both organic electrolytes and inorganic solid electrolytes. In this article, we explore the electrochemical and transport properties of the eutectic binary mixture, Li–K/NO3, using ab initiosimulations and compare against experimental studies. Our analysis of the eutectic mixture shows that the Li+ions are the most mobile species while K+and NO3–ions have lower, comparable mobilities. The high mobility of the Li+ion is found to result from its small atomic radius, which allows more transport through “hopping” between solvation shells than larger ions such as K+. Furthermore, ab initiocomputations of band gaps show much larger stability windows than observed in experiments. Electrochemical stability analysis, performed for the first time using grand-potential analysis on liquid electrolytes, shows that the electrochemical window of the nitrate mixture is restricted by the interface reactions with the electrodes.

The growth of lithium peroxide viaLi–air batteries is investigated using an electrochemical cell-free energy model based on density functional theory. The model builds on previous work to incorporate electrolyte solvation effects with the Poisson–Boltzmann formalism and surface potential effects by adjusting electron population according to a relationship between applied potential and the Fermi level. The model is calibrated to reproduce the behavior of ab initiomolecular dynamics simulations of lithium peroxide slabs in explicit dimethoxyethane electrolytes. The thermodynamics of select growth pathways on low-energy lithium peroxide surfaces show that the incorporation of solvation and potential effects decrease the electrochemical overpotentials on some surfaces and provide estimates in line with experimental measurements. The barriers to disproportionation along the investigated growth pathways are evaluated through nudged elastic band computations. The resulting kinetics and thermodynamics of chemical disproportionation are described well by a linear dependence on potential that conforms closely to the Bell–Evans–Polanyi principle. At both the Li2O2equilibrium potential and at discharge potentials, growth through chemical disproportionation is shown to be thermodynamically favorable and to have minimal activation energy.

When evaluating seismically induced second-order effects in buildings, engineers and researchers are most familiar with these concerns in the context of multistory buildings with rigid diaphragms. However, similar concerns are valid for short single-story concrete or masonry-walled buildings with larger flexible diaphragms, which is a significant portion of the building stock in the United States. These rigid wall-flexible diaphragm (RWFD) buildings may have significant diaphragm drifts causing induced second-order effects. The stability coefficient currently found in ASCE 7 has traditionally been used by practitioners to evaluate the relative risk of P-delta instability in multistory buildings, but this indicator can be adapted for use in RWFD buildings. Using numerical studies following the Federal Emergency Management Agency (FEMA) P-695 collapse assessment methodology to evaluate the risk of collapse for a set of RWFD archetype buildings, a modified stability coefficient for RWFD buildings is found to capture the trend toward P-delta collapse and can act as a reasonable indicator without the need for heavy computational efforts.

Evaluating the candidacy for epilepsy surgery in patients with tuberous sclerosis can be challenging, particularly when non‐invasive investigations do not show a clear epileptogenic zone. Stereoencephalography may be useful in such cases. We present a case in which the primary epileptogenic tuber was successfully identified by stereoencephalography, which resulted in seizure freedom following epilepsy surgery. [Published with video sequences].

The article focuses on navigating changes in the New Zealand food industry and emphasizes the importance of developing Career Capital, encompassing Social, Human, and Psychological components. It discusses the impact of Fonterra's potential sale on career prospects, highlighting the need for professionals to continuously enhance their skills and adaptability amidst industry turbulence, ensuring sustained career success in dynamic times.

The article focuses on the concept of Career Sustainability in New Zealand's dynamic food industry, highlighting the importance of Career Capital, which comprises Social, Human, and Psychological components, and emphasizes the significance of expanding social capital through strategic networking, leveraging mentors and sponsors, and maintaining meaningful relationships to achieve and maintain a competitive edge in the workforce.

The article examines the results of the 2023 Food Industry Salary Survey in New Zealand, emphasizing that smaller companies have implemented more significant salary increases since 2021 compared to their larger counterparts. It discusses how larger companies have utilized additional benefits like professional development, health insurance, and extended parental leave to mitigate the impact of salary increases, allowing them to compete for talent effectively.

by John Lawson, Ion Television As Kermit the Frog often says, 'It's not easy being green.' It's also not easy for producers of quality children's programming to get their shows [...]

With rebates largely unchanged, why are some people contracting back in? Autumn; conkers, fallen leaves, bonfires and fireworks. And contracting out. Each year, just as the clocks are turned back, […]

The twin forces of the 2004 Finance and Pensions Acts will forever change the way that trustees, employers and employees experience additional voluntary contributions. Perhaps the most fundamental of these […]

It looks like the most practical method of moving houses into pensions is to build up the pension fund first and then buy the property Starting in a year's time, […]

Even the wheelbase of the Porsche Carrera GT -- a massive car relative to the F1 -- is 2720mm, a minuscule 2mm longer than the F1's. John was a visiting lecturer to the Royal College of Art while I was there between 1987 and '89 on the MA Vehicle Design course, arriving on a Friday in his Audi 200 quattro. Feature on doing the VSCC "Pom" in Octane 240,I thought my experience of my first-ever VSCC trial might make an interesting comparison. [Extracted from the article]

It is not possible to purchase the office through a self-invested pension plan (Sipp). This is prohibited because a Sipp cannot buy property from a 'connected person'. Although the business [...]

We employed bead-spring models of polymer single-ion conductors to study the impact of chain architecture on ionic aggregation and dynamics. In most simulations, the ionic aggregates were ordered amorphously, but layered ionic structures were also formed in two cases. Here, we focus on the amorphous systems. The local aggregate structure was determined primarily by the ionic interaction strength, with strong interactions yielding blocky aggregates and weak interactions yielding stringy aggregates. Long side chains increased the conformational freedom of the polymer-bound anions, encouraging greater ionic aggregation. Correspondingly, percolated networks of ionic aggregates were common in the long-side-chain systems, while discrete aggregates were more typical of the short-side-chain systems. The aggregates formed physical crosslinks within the system and, therefore, strongly influenced the dynamics. With strong ionic interactions, cations moved more quickly via a shuttling mechanism through percolated aggregates instead of relying solely on the slow rearrangement of discrete aggregates. However, with weaker ionic interactions, the aggregate morphologies were less important, since the lifetimes of ion association were significantly reduced.

We present a combined computational and experimental study, leveraging molecular dynamics simulations and X-ray scattering, to provide molecular-level insights into the layered ionic structures of polyanion electrolytes. X-ray scattering patterns for poly(ethylene oxide-co-allyl glycidyl ether-sulfonate) copolymers, P(EO-co-AGES), with various ion contents and counterions, indicated the presence of narrow lamellar morphologies. Simple bead-spring models, with polymer chain architectures very similar to the fully sulfonated poly(allyl glycidyl ether sulfonate) homopolymer (100 mol % AGES), predicted similar lamellar morphologies formed by stacked sheet-like ionic aggregates. Based on our analysis, we conclude that the ionic groups arrange into stacked layers separated by amorphous backbone layers, with the side groups partially crystallized and oriented nonparallel to the lamellae. Moreover, we propose that (i) the ionic groups are templated within the crystals to yield very stable structures up to high temperatures, and (ii) the layering is driven by the ionic interactions and not crystallization of the side chains. The cation diffusivities and ionic conductivities were severely restricted in the layered ionic morphologies of these materials.

The abstraction of a proton by OH–, O2–, and XO2–from DMEn···X+, where X is Li, Na, or K, is studied using density functional theory. Both the gas phase and the solution phase are studied. In general, when explicit solvent molecules are added, the difference between the gas-phase and solution results becomes rather small. While the DMEn···X+binding energies differ significantly for various alkali cations, the reaction energies and transition-state energies are far less sensitive to the choice of an alkali cation. XO2–has a lower barrier height than OH–, which, in turn, has a lower barrier height than O2–. The reaction energies follow the same trends.

Presents a speech by the senior vice president of the Lawn and Grounds Care Equipment Division, Deere & Company, given during the 25th anniversary of the College of Education, Iowa State University, dealing with the issue of quality and excellence in the workplace. Expectations from companies that hope to compete in the present world and the people who work for them.

Business loan protection policies offer an opportunity for IFAs to beat the banks If you were asked to name a profitable area of financial planning, the chances are that basic […]

Li-based solid-state electrolyte materials enable safer, all-solid-state batteries, but the computational search for candidates with favorable stability and high Li-ion conductivity is challenging due to the size of the search space and the cost of evaluating transport properties with ab initiomethods. We present a high-throughput screening approach for identifying promising materials using a combination of bond-valence methods and graph neural networks. An ablation study involving geometric and bond-valence quantities reveals their relative importance in the training of graph neural networks, providing insight for future modeling of ionic conductivity in Li SSE. We identify 329 candidates with good stability and ionic conductivity, including 28 stable against Li metal. Furthermore, we combine the ML-accelerated screening procedure with an isovalent substitution scheme to generate and screen additional candidates beyond existing databases, identifying an additional 239 candidate materials for battery applications.

This is Part 2 of a two part series of papers on decomposition of two ionic liquids at lithium metal interfaces. In Part 1 of this series, ab initiomolecular dynamics (AIMD) simulations were used to examine the stability and decomposition of two ionic liquids (ILs), [pyr14][TFSI] and [EMIM][BF4], on Li metal anodes. Here in Part 2, density functional calculations of ions and ion pairs in the gas phase are coupled with model electrode surface effects to provide an in-depth analysis of the results obtained from more computationally expensive AIMD simulations of electrolytes on the Li surface in Part 1. The gas phase approach is used to examine the cathodic and anodic stability, the electrochemical decomposition thermodynamics, and the kinetic barriers to the electrochemical decomposition of the ions on a Li surface. The states of the ILs are shown to mix with those of the Li surface, which leads to the reduction of the cations by one electron and a partial reduction of the anions. Upon reduction, many ion decomposition reactions are found to be thermodynamically favorable and to have small or moderate kinetic barriers. An examination of reaction transition states for reduced ions and ions in the presence of Li atoms suggests that the reductive decomposition of anions is mediated by chemical association with Li surface atoms, while reductive decomposition of the cations need not involve such chemical interactions. Overall, the gas phase results obtained here corroborate and extend understanding of the stability and decomposition behavior of ILs on Li metal anodes noted from the AIMD simulations in Part 1.

This work is Part 1 in a two part series that investigates the interfacial decomposition chemistry of [pyr14][TFSI] and [EMIM][BF4] ionic liquids (IL) at Li metal interfaces. Here, the decomposition is probed primarily through ab initiomolecular dynamics (AIMD) simulations. For single ion pairs adsorbed on a Li(100) surface, hybrid ion states are found to emerge about the Fermi level. Interestingly, these states have a significant contribution from both ions, which suggests that the cathodic (reductive) stability could in part be governed by the anions. Room temperature AIMD simulations reveal rapid decomposition of the TFSI anion initiated by C–S and/or S–N bond cleavage due to charge transfer from Li to the anion. The unusual phenomenon of reductive decomposition of the anion is supported by recent experimental reports. The reaction products observed included LiF, LiO, Li2F, Li2O, SO2, NSO2, NSO2CF3, etc., which are all in excellent agreement with the XPS results. Initial decomposition reactions for both cations and the BF4anion were only observed in high temperature AIMD simulations. For bulk ILs interfaces with a Li(100) surface, interfacial decomposition reactions again result from charge transfer to the IL from the Li surface, in particular, to anions at the interfaces. The initial decomposition event at bulk interfaces is found to vary depending on the interface structure. The extensive computational analyses presented in this work provide valuable insights into the fundamental interfacial chemistry of ILs in contact with Li metal. In Part 21 of this series, we consider these results further by systematically examining ion reductive stability, the thermodynamics of decomposition, and kinetic limitations to decomposition using gas phase density functional theory (DFT) computations. Results from these studies can be used for further design of these, or perhaps other, ILs to obtain more stable solid electrolyte interface (SEI) layers to improve cycling in advanced battery chemistries.

Enhancing the power of lithium ion batteries necessitates an understanding of the molecular processes governing Li+ion transfer across the electrode–electrolyte interface. Here, employing enhanced sampling molecular dynamics simulations, we investigated the driving force and thermodynamic barrier of Li+ion adsorption onto Li0.5CoO2(104) electrode in LiClO4-, LiPF6-, and LiTFSI-based EC/EMC (3:7) electrolytes. The weaker cation–anion pairing in LiTFSI compared to LiClO4was found to enhance the driving force for adsorption from −0.48 eV in LiClO4to −1.26 eV in LiTFSI for an electrode–electrolyte interface with zero cation coverage, which was accompanied by an increased thermodynamic barrier from 0.33 eV in LiClO4to 0.43 eV in LiTFSI at an equilibrium surface coverage of Li+ions. The hindered diffusivity of the solvent molecules in the electric double layer (EDL) at the electrode–electrolyte interface was the main contributor to the thermodynamic barrier for ion transport. The entropic component of the thermodynamic barrier was found to be more than 1 order of magnitude smaller for ClO4–compared to TFSI–, which can be attributed to the presence of more ClO4–than TFSI–in the EDL, causing more structural changes in the EDL. The strong dependence of the entropic component of the thermodynamic barrier on the EDL structure enables its decoupling from the enthalpic components (e.g., ion-pairing that can be tuned independently) and thus can be used to control the kinetics of the interfacial transport. This work provides a fundamental understanding of the thermodynamic and kinetic parameters involved in Li+ion adsorption, which is a crucial step in the performance of Li+ion batteries.

LIGHT, Michael. Full Moon. 225p. photos. Knopf. 1999. Tr $50. ISBN 0-375-40634-4. LC 98-83094. YA--A San Francisco artist and photographer has pulled together 129 stunning, black-and-white and color photographs from [...]

Attitude--not altitude--is often the greatest obstacle humans face. Many individuals cannot see past disabilities and find the people behind them. But sometimes you get lucky. As I drove down the [...]

Epidemiological studies suggest that there exists a beneficial effect on low to moderate alcohol consumption on the incidence of cardiovascular disease. Once ingested, alcohol is metabolized to acetaldehyde, a two-carbon, [...]

Li–O2batteries have traditionally used carbon-based electrodes (graphite, buckypaper) as the cathode of choice due to their good electrical conductivity, stability against nonaqueous electrolytes like dimethoxyethane, and ease of handling. But, the carbon cathode also leads to the formation of carbonate byproducts that increase overpotentials during charging, leading to degradation of the cathode and reduction of cyclability. Recent investigations have focused on using metal oxides like SnO2, TiO2as viable cathode alternatives in Li–O2systems. In this paper, we investigate transparent conducting oxides (TCOs) as cathodes, with focus on the interface between the TCO surfaces and the discharge product, Li2O2, in the Li–O2battery using first principles computations. We also explore the role dopants can play in achieving a stable electrically conducting cathode that promotes discharge of Li2O2. Our results show that attention must be paid to choosing appropriate surface of these oxides. We extend the analysis to suggest possible oxide chemistries that should be investigated as cathodes in Li–O2batteries.

This paper examines four methods used to assess the value of the benefits and costs of freight transportation from a broader lens than just economic value. As with any mode of transportation, the benefits and costs of freight transport are numerous and diverse, and there is no widely agreed-on approach for assessing the values. The key focus of the paper is to examine how transport industries and modes are valued. However, the methodologies ultimately chosen need to reflect the purpose (or objective) of the valuation. In exploring the strengths and limitations of four methods of assessing value, this paper may assist others exploring the value of various modes of transportation. The paper concludes that adoption of more than one approach to measuring value provides a more holistic understanding of the role played by a mode of transportation, whether the perspective is one of government, industry or citizen.