bluuebunny/crossref_metadata_2025_split huggingface dataset:
New Bimetal Catalysts Supported on Silica Nanospheres for the Production of Synthetic Diesel
Authors: Neira Carlos , Ortiz Dayna M. , Arango Juan C. , Márquez Francisco , de Jesús Abniel M. 
Published: February 2020

Nowadays we are facing the necessity to find new ways to reduce the use of fossil fuels. This need comes from the excessive use of these sources as energy and the well-known adverse environmental effects than these fuels represents. Currently the fossil fuels represents about the 70% of the world energy sources. This dependency has brought some important problems of contamination such as global warming and climate change, acid rain, alterations of the carbon cycle, among many others. The transportation sector is the largest consumer of petroleum-based fuels in the world, liberating to the atmosphere vast amounts of CO2, NOx, SOx, lead (Pb), mercury (Hg), and many others. These pollutants are not only harmful to the environment but also to the human health, causing lung and heart diseases along with cancer. The increase of price and demand of these fuels and the contamination generated by them makes imperative the search of viable clean technologies looking for the production of clean fuels with high commercial value. Contaminants produced by the combustion of fossil fuels represent a challenging future for the development of new clean fuels. In this regard, an interesting alternative consists in the synthesis of clean diesel fuel thorough the Fischer-Tropsch (FT) reaction. This method produces clean diesel starting from a mixture of H2 and CO obtained from renewable or not renewable energy sources. This synthesis produces high weighted hydrocarbons with high purity. The fuel produced by this process is clean since it does not have aromatic compounds or sulphur or nitrogen-based compounds, preventing the production and release of NOx and SOx during combustion. The FT processes require the use of heterogeneous catalysts. These catalysts are based on active metals (i.e. Co, Ru or Fe) highly dispersed on the surface of appropriate supports. In this research SiO2 nanospheres, synthesized by using the Stӧber procedure, have been used as supports for the deposition of different metals on the surface. The synthesized catalysts were characterized by FE-SEM, HRTEM, XRD and BET, and used for the FT reaction. Preliminary catalytic results are very promising and show that mixtures of low loadings of bimetal nanoparticles dispersed on the surface of SiO2 nanospheres could be efficiently used for the synthesis of paraffin products with different distribution.
(Invited) Beyond Vapor Compression Technologies
Authors: Bouza Antonio M 
Published: February 2020

The Building Technologies Office (BTO) of the U.S. Department of Energy (DOE) seeks to accelerate the development of the next generation of heating, ventilation, and air-conditioning (HVAC) technologies, including both electric- and natural-gas-driven solutions. HVAC is the largest energy end-use for U.S. buildings, consuming approximately 37.3% (~15 Quads) of total energy.[1] Vapor compression based systems have effectively and efficiently served the HVAC needs for residential and commercial buildings for close to 100 years. Vapor compression technologies are currently the dominant HVAC technology due to their scalability, relatively compact size, high reliability, and other attributes. However, the refrigerants used in these systems have detrimental global effects on the environment when released into the atmosphere. The scientific community has responded to such environmental threats by several proposals to phase down refrigerants with large global warming potential (GWP).
What is needed is a paradigm shift in HVAC technologies, moving beyond today’s refrigerants and toward a future based (at least in part) on non-vapor-compression HVAC technologies with the ultimate goal to eliminate high GWP refrigerants all together. This new paradigm is the ultimate environmental solution (zero GWP cooling fluids), provides energy savings for consumers, and will enable manufactures to avoid the challenge of future refrigerant change out cycles. A primary objective is to focus on an end-state with no refrigerants required, while enabling U.S. manufacturers to innovate in ways that will enhance their competitiveness over the longer term.
What comes after vapor compression technology? U.S. Department of Energy has recently completed a report on the Energy Savings Potential and RD&D Opportunities for Non-Vapor-Compression HVAC Technologies to help frame the state of these next generation technologies. Possible candidate technologies include, but are not limited to: sorption technologies, alternative thermodynamic cycles, solid state technologies, membrane technologies,
electrochemical cycles
, and mechanical technologies. BTO currently has several projects that use electrochemical cycles in its HVAC, Water Heating and Appliance R&D portfolio.

[1] http://buildingsdatabook.eren.doe.gov/
(Invited) Predicting Electrocatalytic Properties: Modeling Structure-Activity Relationships of Nitroxyl Radicals
Authors: Hickey David P , Schiedler David , Matanovic Ivana , Doan Phuong Vy , Atanassov Plamen , Minteer Shelley D. , Sigman Matthew S 
Published: February 2020

Recently there has been an increased interest in the development of small molecule electrooxidation catalysts such as (2,2,6,6-tetramethylpiperidin-1-yl)oxyl (TEMPO), for use in the anodic compartment of a biofuel cell. Some TEMPO derivatives are capable of electrochemically oxidizing short chain alcohols and various sugars to the corresponding aldehydes and carboxylic acids under physiological aqueous conditions. However, building libraries of such a catalyst is difficult due to the limited number of commercially available TEMPO derivatives and the lack of modular synthetic pathways to more complicated TEMPO structures. A promising alternative to the physical preparation of such libraries is the use of computational modeling to allow for in silico catalytic screening of a much wider range of TEMPO compounds.
Based on experimental results, we have developed a computational model to probe the structure-function relationships that determine the catalytic activity of a diverse range of water-soluble nitroxyl radical compounds. A strong correlation was found between the difference in the electrochemical oxidation potentials of a compound and its electrocatalytic activity. The newly developed computational model is able to accurately predict the electrochemical potential and catalytic activity of a wide range of nitroxyl radical derivatives.
Identifying the Electrochemical Conditions of Underpotential Deposition and Its Role in Shape-Controlled Synthesis from First Principles
Authors: Weitzner Stephen , Dabo Ismaila 
Published: February 2020

Recently, much attention has been devoted to the development of synthetic approaches that can exert facile control over the size, shape, architecture and composition of transition metal nanoparticles (TMNPs). The advent of such approaches could enable the rational design of nanoelectrocatalysts, as the catalytic properties of TMNPs are highly sensitive to their morphologies and elemental compositions. One strategy that is actively being investigated involves the underpotential deposition (UPD) of transition metals onto the surfaces of seed TMNPs. UPD-based approaches for shape control are attractive since the deposition process is surface-sensitive and is easily controlled by varying the synthesis conditions, such as the transition metal salt concentration and the pH of the electrolyte. Nevertheless, the ability to predict the equilibrium shape of UPD-modified TMNPs is challenging because of difficulties in modeling the UPD process in electrolytic media. Therefore, in order to develop a strong connection between the synthesis conditions and the equilibrium shapes of UPD-modified TMNPs, better theoretical descriptions of UPD phenomena are required. In this work, we report progress on the first-principles modeling of UPD phenomena under realistic electrochemical conditions. Key to this model is the ability to include the influence of solvent dipoles and the electrical double layer along the solid–liquid interface. We capture these effects through a recently released solid–solution interface model. Employing this approach, we are able to accurately calculate the measurable shift in redox potential associated with the UPD process on planar surfaces, as well as the adsorption isotherms including entropic effects. The development of this predictive first-principles UPD model and extensions to modeling equilibrium TMNP shapes are discussed.
The Influence of Coupled Faradaic and Charging Currents on Impedance Spectroscopy
Authors: Wu Shao-Ling , Orazem Mark E. , Tribollet Bernard , Vivier Vincent 
Published: February 2020

Passage of current in electrochemical systems can be attributed to faradaic reactions and to double-layer charging. Faradaic and charging currents are usually considered separately when developing models for the impedance response [1]. Delahay [2] criticized the assumption that charging and faradaic currents are uncoupled on the grounds that part of the flux of reacting species must contribute to the charging of the interface as well as to the faradaic reaction. Nevertheless, the accepted procedure for model development has been to assume that the faradaic and charging currents are independent.
When charging and faradaic currents are considered uncoupled, the flux of reacting species contributes only to the faradaic reaction. Under the assumption that charging and faradaic currents are coupled, the reacting species are seen to contribute to both the faradaic reaction and, along with the inert species, to the charging current.
Relaxation of the assumption that faradaic and charging currents are independent requires coupling an explicit model of the double layer to the convective diffusion equations for each ionic species. Nisancioglu and Newman [3] provided an appropriate mathematical formalism, used by Wu et al.[4] to model the impedance response of a rotating disk electrode.
Through numerical simulation, the coupling of faradaic and charging currents is shown to result in impedance responses yielding frequency dispersion that resembles Constant-Phase-Element (CPE) behavior. The results show that coupling of faradaic and charging currents should be considered when modeling the impedance response for systems influenced by mass transfer, even for large concentrations of supporting electrolyte. Features of the simulations are compared to the results of experiment.
References

J. H. Sluyters, Recl. Trav.
Chim. Pays-Bas,
79 (1960), 1092-1100.

P. Delahay, J. Phys. Chem.,
70 (1966), 2373-2379.

K. Nisancioglu and J. S. Newman, J. Electrochem. Soc., 159 (2012), E59-E61.

S.-L. Wu, M. E. Orazem, B. Tribollet, and V. Vivier, Electrochim. Acta,
131 (2014), 3-12.
Phase-Field Modeling of Metal Plating on Battery Electrodes
Authors: Fang Alta , Haataja Mikko 
Published: February 2020

The growth of ramified metal deposits on battery electrodes during charging can lead to capacity loss as pieces of metal become electrically disconnected upon cycling or result in battery failure as metal dendrites penetrate the separator and short-circuit the cell. This undesirable metal plating can occur in Li-ion batteries under conditions of fast charging, overcharging, low temperature, or in the presence of battery separator defects. Nonuniform electrodeposition is also a challenge faced by next-generation battery technologies with pure metal anodes. Developing a better understanding of how different electrodeposit morphologies form inside batteries could lead to more effective strategies for preventing dendrite growth, making Li-ion batteries safer and metal anodes more practical.
Phase-field modeling is a promising approach for modeling electrodeposition morphologies and has been used extensively to simulate a variety of complex microstructural evolution processes. We have developed a phase-field model of electrodeposition from a binary electrolyte that accounts for Butler-Volmer reaction kinetics, the metal-electrolyte surface energy, and ion transport via diffusion and migration. We validate our model with linear stability analyses and numerically simulate the formation of various morphologies under different conditions. In addition, we simulate dendrite growth through a porous battery separator and explore the effects of separator properties on the growth of the metal electrodeposits.
High Capacity and High Power Ncm/Graphite Lithium Ion Battery Using Microgrid® Expanded Metal Current Collectors
Authors: Zhang Zhifeng , Chen Zhenlian , Zhang Xianhui , Li Yantu , Zhang Qinggang , Hart John , Li Jun 
Published: February 2020

To achieve better sustainable power application of LiNi1/3Co1/3Mn1/3O2/graphite lithium ion battery, new cell structures using Microgrid® expanded metal current collectors were studied. By adopting the Microgrid® foil for cathode electrodes, the performance of LiNi1/3Co1/3Mn1/3O2 electrodes was significantly improved at high rate discharge at both room and low temperature. Scanning electron microscopy was carried out to reveal coating features of Microgrid® cathode electrodes. The loading density of active materials can be increased by the pore structure, and the 10C capacity retention of Microgrid® electrode is 25.8% higher than that of a conventional electrode after 100 cycles, and nearly doubled for the initial discharge at 10°C. There is the potential for enhancement of cell performance using Microgrid® foils in place of conventional foils with LiNi1/3Co1/3Mn1/3O2 cathode and graphite anode. The Microgrid® full cell shows 209.0% increase of capacity with respect to conventional cells of Al and Cu foils for 10C after 100 cycles and keeps the retention rate 12% higher than the latter. Microgrid® foils can potentially be applied to other electrode materials which are suffering from capacity fade at high C-rates and at higher loading densities.

Figure 1
Organic Vs. Inorganic Cations of Alkali-Metal Halides Containing Ionic Liquids for Sodium-Ion Battery Applications
Authors: Tucker Telpriore Gregory , Angell Charles Austen 
Published: February 2020

The power generation from either fossil fuels or preferably renewable energy sources is on the rise throughout the world. The pursuit of electrochemical devices for energy storage during peak power grid utilization is viable. There is great interest in further developing sodium batteries, particularly ZEBRA-type cells with chloroaluminate electrolytes. This lab has worked on understanding of weak-field, low-melting metal-halide based ionic liquids for use in the sodium-ion conducting batteries at a low-temperature of operation. This undertaking employed both organic and inorganic cations of low charge density, including the much-studied dialkylimidazolium cation. The vital issue of decreased ionic conductivity caused by alkali ion-trapping in these electrolytes long known as a qualitative effect was recently quantified, discussed, and reported by us. We have since compared the conductivities of binary bromoaluminates in which large inorganic cations PBr4
+ formed by a bromide transfer process were used to replace the former dialkylimidazolium cation and here show the differences in the figure below. Currently, the electrochemical (along with other physical) properties are being characterized in preparations for testing in ZEBRA-type cells. This study leads to improved understanding of the factors determining electrolyte and electrochemical performance of sodium-containing binary electrolytes over a range of temperatures.
Figure: The top set of three conductivity isotherms are for [EMIM]AlCl4 - NaAlCl4 solutions, and the bottom set of three are for PBr4Al2Br7 - NaAl2Br7 solutions of varying molar fractions. The completely inorganic electrolyte requires 100oC (top blue line isotherm) to attain the ionic conductivity of the electrolyte containing the organic cation at 60oC (mid black line isotherm). We attribute the difference to incomplete bromide transfer in the formation of the large inorganic cation of the second system. The “alkali cation-trapping” effect probably remains in effect.

Figure 1
Raman Imaging of Cells Using Antibody-Derived Carbon Nanotubes Nanoprobes
Authors: Nascimento Rafaella Oliveira , Tang Nathalie , Allard Charlotte , Nguyen Minh , Birlea Mirela , Gaboury Louis , Martel Richard 
Published: February 2020

Microscopy of biological samples with fluorescent dyes exhibits strong signals, but also limitations such as photobleaching, poor long-term stability and low multicolour capabilities. In contrast, Raman imaging of molecules is better adapted for multiplexing, but its intrinsic signal is too weak to be useful for high resolution imaging. To compensate for the low sensitivity of Raman, contrast agents (probes) have been developed over the years to boost the Raman signal to levels near that of fluorescence. By encapsulating dyes inside single-walled carbon nanotubes (dyes@SWCNTs), our group has highlighted interesting optical properties that make them suitable as Raman nanoprobes [1]. Not only these probes show giant Raman signal from the dyes, but they are resistant also to photobleaching and offer multiplexing capabilities as well as versatile chemistry at their surfaces. Recently we show that PEGylated dyes@SWCNTs can indeed be used as nanoprobes having good Raman multiplexing properties for biological imaging [2]. Here, we will present recent results on their covalent functionalization with bifunctional polyethylene-glycols (NH2-PEG-R). A full physicochemical characterization of the probes carried out using TGA, Raman spectroscopy, AFM and 1H NMR will be presented. The covalent functionalization of these Dyes@PEGylated-SWCNTs nanoprobes with antibodies was developed to produce active targeting agents for cells. Using Raman hyperspectral imaging, we have demonstrated that these antibody-functionalized nanoprobes can effectively target living or fixed human and mouse cancer cells and that they can selectively attach, depending on the antibody, to specific targets immobilized on surfaces.
[1] E. Gaufrès, N.Y.-W. Tang, F. Lapointe, J. Cabana, M.-A. Nadon, N. Cottenye, et al., Giant Raman scattering from J-aggregated dyes inside carbon nanotubes for multispectral imaging, Nat. Photonics. 8 (2013) 72–78. doi:10.1038/nphoton.2013.309.
[2] N. Cottenye, N.Y.-W. Tang, E. Gaufrès, A. Leduc, J. Barbeau, R. Martel, Raman tags derived from dyes encapsulated inside carbon nanotubes for Raman imaging of biological samples, Phys. Status Solidi. 211 (2014) 2790–2794. doi:10.1002/pssa.201431401.
[3] This work was made possible because of financial support from NSERC (Canada) and Photon Etc.
(Invited) Carbon Nanotubes and Cellular Perturbation: Augmentation of Differentiation Dynamics in Neural Stem Cells
Authors: Jedlicka Sabrina , Pirbhai Massooma , Rotkin Slava V. 
Published: February 2020

Delivery of materials, such as drug compounds or imaging agents for treatment or diagnosis of disease still presents a biomedical challenge. Nanotechnological advances have presented biomedicine with a number of agents that possess the appropriate size and chemistry to pass through the blood brain barrier. Functionalized carbon nanotubes are one such agent, which can potentially aid in drug and gene delivery to the central nervous system. In addition, carbon nanotubes have already been applied in several areas of nerve tissue engineering to probe and augment cell behavior, to label and track subcellular components, and to study the growth and organization of neural networks. Although the production of functionalized carbon nanotubes has escalated in recent years, knowledge of cellular changes associated with exposure to these materials remains unclear. Thus, it is crucial to develop an understanding of the effects and interactions that carbon nanotubes can induce in a living system. In this study, carbon nanotubes, wrapped with either GT20 DNA or yeast tRNA were introduced to neural stem cells during proliferation and differentiation, at doses determined to be non-lethal. At non-lethal doses, cell fate can be dramatically impacted by the carbon nanotube materials. Depending upon the mode of exposure, the differentiation dynamics are significantly altered, leading to at least a one-fold increase in the final percent of neurons in the total population. This increase in neuronal population is mathematically correlated to a change in the division symmetry of the dividing cells early in the differentiation process. In addition, the results demonstrate that the irregular patterns of cell fate are due to a variety of biophysical inputs stimulated by the carbon nanotubes, including, but not limited to, cytoskeletal perturbation, focal adhesion augmentation, and subcellular localization of the nanomaterials. Acknowledgment: NSF ECCS-1509786.
Examining the Sub-Cellular Localization of Single-Walled Carbon Nanotubes
Authors: Langenbacher Rachel E , Budhathoki-Uprety Januka , Roxbury Daniel , Jena Prakrit Vaibhav , Heller Daniel A 
Published: February 2020

Single-walled carbon nanotubes have a number of properties of interest for their development as sensors and molecular probes for use in biological media. They are inherently fluorescent in the near-infrared “tissue transparent window” and do not photobleach. Multiple, optically distinct nanotube species can be used for extensive multiplexing in a single sample. To preserve these desirable qualities while solubilizing and functionalizing the hydrophobic nanotube, we have developed non-covalent wrappings consisting of helical polycarbodiimide polymers. The polymers can be modulated to control internalization and sub-cellular localization. Assessing the localization of carbon nanotubes is of the utmost importance for their further development in biological applications.
Superconducting Properties in Tantalum Decorated Three-Dimensional Graphene and Carbon Structures
Authors: Pan Wei 
Published: February 2020

Unlike a two-dimensional (2D) electron system at the interface in a heterostructure, the 2D electrons in graphene are open to environment. As a result, many studies have been carried out in examining how adsorption of metal adatoms on graphene sheet can modify its electronic properties. For example, a tunable superconducting phase transition was recently observed in a tin decorated graphene sheet. There, the non-percolating tin clusters dope the graphene sheet and induce long-range superconducting correlations. More excitingly, it was predicted that lithium decorated graphene can display a much higher superconducting transition temperature than in the superconductivity in bulk graphite intercalated by lithium atoms. Three-dimensional (3D) graphene structures, a flexible and conductive interconnected graphene network, have generated a great deal of interests in recent years. Compared to a 2D graphene sheet, surface area in a 3D graphene structure is greatly enhanced. Furthermore, 3D graphene maintains the outstanding electrical, thermal, and mechanical properties as in 2D graphene. Therefore, 3D graphene structures are expected to play an important role in flexible electronics, sensors and energy storage applications (e.g., supercapacitors, battery electrodes, and hydrogen storage).
In this talk, I will present our recent electronic transport results on superconducting properties in tantalum decorated 3D graphene and carbon structures, following pioneering work of decorating 2D graphene sheets with superconducting materials. A superconducting transition is observed in both composite thin films. The magnetoresistance at various temperatures and differential resistance dV/dI at different magnetic fields were also carried out. Moreover, an anomalously large cooling effect was observed in the differential resistance measurements in our 3D graphene - tantalum composite when the device turned superconducting. This surprisingly large cooling effect plus the nature of flexible 3DG thin film may find promising applications in solid-state cooling.