bluuebunny/crossref_metadata_2025_split huggingface dataset:
Digital Voltage-Current Time Differential Method for Operating Zirconia-Based NOx Gas Sensors
Authors: Woo Leta , Bell Frank , Boettcher Mike , Chee James , Fitzpatrick Joe , Henderson Brett , Sorensen Lee , Wang Victor , Novak Robert , Visser Jaco 
Published: February 2020

Gas sensors are important for monitoring and controlling combustion technologies. In particular, NOx compounds (NO and NO2) that are present in diesel exhaust cause poor air quality and act as both pollutants and greenhouse gases. Commercially available NOx sensors for vehicle applications use high-temperature solid-state ceramic electrochemical technology similar to the ubiquitous automotive oxygen sensor; however, commercial NOx sensors are much more expensive than their oxygen sensor counterparts due to their complicated design with multiple cells (as opposed to the single-cell oxygen sensor) and their expensive electronics for measuring low-current signals (as opposed to the voltage signal from oxygen sensors). Therefore, a NOx sensor alternative that meets stringent operational requirements at a reduced cost is desired for automotive and other combustion applications.
Conventional solid-state electrochemical sensors operate with direct current (dc) methods that are either current-based/amperometric or voltage-based/potentiometric. In this work, we use alternating current (ac) impedance-based/impedancemetric operation of zirconia-electrolyte-based sensors for NOx detection. The solid-state electrochemical cells are comprised of two electrodes separated by the zirconia electrolyte, where both electrodes are exposed to the test gas. The impedance-based response of the simple single-cell sensor relies primarily on multiple concurrent non-equilibrium steady-state interfacial redox reactions. Impedance spectroscopy was used to investigate sensing mechanisms, and sensor operation was performed at pre-determined frequencies to demonstrate stable, reproducible sensor behavior.
Since laboratory impedance spectroscopy evaluation usually employs expensive analytical equipment, a novel, low-cost, portable signal processing method was developed using a digital voltage-current time differential method. The applied signal was an alternating current electrical waveform, and the response of the sensor was digitally measured directly in the time domain; laboratory impedance evaluation usually measures in the frequency domain. Results of the low-cost digital signal processing indicated the potential for increased NOx sensitivity and improved sensor performance compared to the much more expensive frequency-domain impedancemetric method.
Multiplexed DNA Biomarker Detection with Phase Change Nanoparticles
Authors: Su Ming 
Published: February 2020

A number of microRNAs (miRNAs) are found in body fluids of patients. The challenge of using these biomarkers for early detection of diseases is that most of them have low concentrations, are not powerful enough when monitored singly, lacking sensitivity or specificity. Parallel to the efforts to find better biomarkers, one possible way is to detect more biomarkers and collectively analyze their profiles.
This talk describes a multiplexed highly-sensitive technique to detect miRNA biomarkers using solid-to-liquid phase change nanoparticles. The nanoparticles of metals and eutectic alloys with sharp melting peaks will be modified with single strand DNAs (ssDNAs), which specifically bind to one end of miRNA biomarkers. A panel of nanoparticles with composition-dependent melting temperatures will be utilized to detect multiple biomarkers after establishing a one-to-one correspondence between one type of nanoparticle and one type of biomarker. An aluminum substrate with high thermal conductivity will be modified with a panel of ssDNAs that are complementary to the other ends of miRNA biomarkers. The detection scheme is that: (1) the receptor-modified nanoparticles will be incubated in a buffer containing biomarkers; (2) after centrifugation to remove unbound species in blood, biomarkers attached on nanoparticles will be re-suspended in another buffer; (3) the substrate will be immersed in the buffer to catch nanoparticles by forming DNA-RNA duplex; (4) the substrate will be washed to remove excess nanoparticles, and the attached nanoparticles will be readout with differential scanning calorimetry (DSC), where the temperature and area of melting peak reflect the presence and amount of biomarker.
Ten different metals that can form binary eutectic alloys among any two of them are identified. They can form 1,023 types of metallic and eutectic alloy nanoparticles. The compositions and melting temperatures of high order eutectic alloys are determined by calculation of phase diagram. Based on the eutectic compositions, nanoparticles are made by thermally decomposing organometallic precursors in a high boiling point solvent (ethylene glycol) using polyvinyl alcohol as surfactant. The nanoparticles and the aluminum substrate are modified with thiolated probe ssDNA and capture ssDNA, respectively. The lowest target concentration that can be detected is 80 pM. Further, the thermal ramp rates are remained constant to readout indium nanoparticles, but are changed from 1 to 10 °C/min to readout bismuth nanoparticles. The variable ramp rate in the same scan allows ten time adjustment of heat flux (sensitivity). Four different miRNAs are simultaneously detected with four types of nanoparticles, tin, tin-lead alloy, indium and bismuth.
Detection of Salmonella
Enterica Typhimurium in Chicken Meat Using Phage Coated Magnetoelastic Sensors
Authors: Chen I-Hsuan , Horikawa Shin , Chin Bryan A. , Barbaree James M 
Published: February 2020

According to the Centers for Disease Control and Prevention (CDC), from 2011-2014, there were at least several outbreaks in the U.S. due to Salmonella associated with chicken. Our goal was to improve food safety in this area, and develop a real time detection system. We developed and demonstrated the use of our phage C4-22 immobilized onto a rapid magnetoelastic (ME) biosensor system for use as a front-line detection ligand to detect all Salmonella
enterica serotypes in TBS model.
Here, we confirm the phage peptide binding to Salmonella
typhimurium cells by fluorescent imaging (Fig. 1 and 2.) Figure 1 showed the Salmonella cells only without C4-22 phages with magnification of 100x. In figure 2, it is the binding of fluorescent labeled phages (1x1011 vir/ml) and Salmonella, viewing under fluorescent microscope with fluorescein isothiocyanate (FITC) filter and with magnification of 100x.
Moreover, we show the construction of a chicken model to evaluate the detection of Salmonella on/in chicken meat using the phage coated sensor. In the surface detection system, S. typhimurium solutions at four concentrations of 2.5x106, 5x106, 2.5x107, and 5x107 cfu/ml were inoculated on the surface of chicken breast. Three phage sensors as a test group were placed on the chicken surface for detection. Experiments were repeated twice. Phage sensors were prepared by coating the ME sensors with 1x1010 virons phage C4-22 in TBS. BSA (0.1%) was used as a blocking reagent on the sensor. Sensors coated with 0.1% BSA only served as controls. Cells of S. typhimurium detected on the sensor were eluted with 0.1M Glycine to break phage-Salmonella binding. The percent of Salmonella binding to the phage coated sensor was determined using a standard aerobic plate count method with TSA and BG plates. Phage C4-22 sensors demonstrated more than 12 times higher Salmonella binding capacity than the control sensors at the Salmonella loading concentration of 5x107cfu (Fig.2).
During the experiments, it was found that the spiked Salmonella solution was quickly absorbed by the chicken meat. In the second chicken model, phage sensors were placed at different depths (0.1cm; 0.5cm; 1.0cm below the surface; Fig. 3) inside the chicken after inoculation of Salmonella for 15min. Our data show more than 30% of the inoculated Salmonella cells absorbed inside the chicken meat below 0.1cm of the chicken surface. The percentage of the biosensor captured Salmonella decreased while the detection depth increased.
In summary, phage C4-22 ME biosensors detect well when there are high concentrations of Salmonella on the chicken surface. The inside meat detection allow us to effectively monitor Salmonella cells which were absorbed into the chicken and unable to detect by the biosensors while using a surface detection method.

Figure 1
Electrochemical Quantification of Vanadium By Novel Electroanalytical Technique
Authors: Salazar-Gastelum Moises Israel , Botte Gerardine G 
Published: February 2020

Background

The chemistry of vanadium is noticeable since four oxidation states are adjacent (+2, +3, +4, +5), moreover, vanadium can be founded in 65 different minerals and fossil fuel deposits such as petroleum, coals, lignite, oils, pet-coke and so on [1].
Due to the nature and complexity of vanadium samples, it is necessary to set up an analytical technique easy, fast and inexpensive. In this paper, the electrochemical measurement of multivalent cations concentration (EM2C2) technique is extended and demonstrated to determine the concentration of the redox pair V(IV)/V(V) in aqueous solutions simultaneously.

Methodology

The EM2C2 technique consists in the measurement of the limiting current under diffusion limitations using a rotating disk electrode [2]. Different parameters in the technique were investigated, such as scan rate potential, rotation rate of the electrode, and interferences in the measurements.

Results

Preliminary results show that V(IV) and V(V) could be determined measuring the upper and lower limiting current, respectively (Figure 1).
The upper liming current increases at higher concentrations of V(IV) and lower limiting current increases at higher concentration of V(V). Hence, the upper liming current is the analytical signal of V(IV) and lower limiting current is the analytical signal of V(V).
Preliminary results demonstrate that simultaneous quantification of V(IV) and V(V) could be achieved in 1 minute with a detection limit of 1.0 mM for both species.
However, due to the complexity of the samples, other factors may cause interferences in the measurements. Further results will be presented at the meeting including the effect of electrolyte, rotating speed and the presence of other ions in solution.

References

1. M. J. Ahmed, S. Banoo, “Spectrophotometric method for determination of vanadium and its application to industrial, environmental, biological and soil samples”, Talanta 48, (1999), 1085-1094
2. X. Jin and G.G. Botte, “Electrochemical technique to measure Fe(II) and Fe(III) concentrations simultaneously”, Journal of Applied Electrochemistry 39, (2009), 1709-1717.

Figure 1
Biomaterials Research Support at the National Science Foundation
Authors: Simonian Aleksandr 
Published: February 2020

The NSF/DMR/BMAT perspective on biomaterials research and education will be presented, as well as a description of ongoing and forthcoming research funding opportunities. It will start by providing an overview of divisions and programs at the NSF where an applicant may consider submitting proposals for biomaterials related research. This presentation will be particularly useful to early career researchers in the field of biomaterials and biosensors.
The Biomaterials program supports fundamental materials researchrelated to (1) biological materials, (2) biomimetic, bioinspired, and bio-enabled materials, (3) synthetic materials intended for applications in contact with biological systems, and (4) the processes through which nature produces biological materials. Projects are typically interdisciplinary and may encompass scales from the nanoscopic to the bulk. They may involve characterization, design, preparation, and modification; studies of structure-property relationships and interfacial behavior; and combinations of experiment, theory, and/or simulation. The emphasis is on novel materials design and development and discovery of new phenomena.

General information on all the programs in DMR can be found on the DMR Web page: http://www.nsf.gov/div/index.jsp?div=DMR. In addition, attendees will have the opportunity to interact “one on one" with NSF BMAT Program Director.
Amperometric Detection of Plant Volatiles Using Metal Oxide Nanoparticles
Authors: Fang Yi , Ramasamy Ramaraja P. 
Published: February 2020

Volatile organic compounds released by pathogen-infected plants can be used as fingerprints for plant disease detection via electronic nose technologies1,2. In this work, nanoparticles of TiO2 or SnO2 modified on screen-printed carbon (SP) electrodes have been developed for detection of fruit volatiles using amperometric techniques. p-ethylguaiacol, is a characteristic compound present in the volatile signature of fruits infected with a pathogenic fungus called Phytophthora cactorum. The electroanalytical data obtained using cyclic voltammetry and differential pulse voltammetry showed that both SnO2 and TiO2 exhibited high sensitivity (174–188 mA cm-2 mM-1) and low detection limits (35–62 nM) for p-ethylguaiacol detection3. Both biosensors were evaluated for interference by adding common green leaf volatiles (cis-3-hexel-1-ol, hexyl acetate and cis-3-hexen-1-yl acetate). The results demonstrate that both metal oxides are a reasonable alternative to expensive electrode materials such as gold or platinum for amperometric sensor applications.

Reference

T. Baldwin, A. Kessler and R. Halitschke, Curr. Opin. Plant Biol., 2002, 5, 351.

P. W. Par´e and J. H. Tumlinson, Plant Physiol., 1999, 121, 325.

Y. Fang, Y. Umasankar and R. P. Ramasamy, Analyst., 2014, 139, 3804

Figure 1
Development of Simultaneous Measurement Method of Potentiodynamic Polarization Curve and Impedance Spectra Determined By Wavelet Transformation
Authors: Kato Seiya , Hoshi Yoshinao , Shitanda Isao , Itagaki Masayuki 
Published: February 2020

Electrochemical impedance spectroscopy (EIS) is powerful method to analyze dissolution mechanisms of metals because time constants for elementary reaction steps and formation of reaction intermediate can be discriminated. Impedance spectrum is generally measured by using a frequency response analyzer (FRA) whose principle is on the basis of Fourier transformations of sinusoidal input and output signals. Ragoisha et al. (1) proposed a potentiodynamic electrochemical impedance spectroscopy (PDEIS), in which sinusoidal wavelet is superimposed on terrace of the each potential step during stepwise potential scan. Our group (2, 3) developed a simultaneous measurement method of a potential scanning impedance spectroscopy (PSIS) and impedance spectra determined by wavelet transformation (WT). In this method, it is possible to obtain the successive impedance spectra with measuring the potentiodynamic polarization curve of metal electrode simultaneously and to determine the instantaneous impedance. We used complex Morlet mother wavelet in order to obtain the complex number data in the frequency domain. This mother wavelet is obtained by combining the Gaussian function and sinusoidal term. The time-dependent impedance of the dissolving iron electrode can be determined by calculating cross spectra of the wavelet coefficients of current and potential signals. In the present paper, the potential step signal was used for the input signal. In the results, the impedance spectrum described the capacitive loop in the high frequency range and the inductive loop in the low frequency range, which was determined by WT. It was found that the impedance spectrum in the low frequency range determined by WT is related to the holding time of input potential signal. The inductive loop observed in the low frequency range and the holding time of input potential signal were discussed.
Reference:
1. G. A. Ragoisha and A. S. Bondarenko, Electrochimica Acta, 50, 1553 (2005).
2. M. Itagaki, K. Isobe, Y. Hoshi, I. Shitanda, 226th ECS meeting abstract, #753 (2014).
3. M. Itagaki, A. Taya, K. Watanabe, Electrochemistry,
70, 779 (2002).
Structure and Li+ Dynamics of the Single-Ion Conducting Polymer Electrolyte P(STFSI)-Ran-PEGMA
Authors: Schaefer Jennifer L , Orski Sara V. , Nieuwendaal Ryan C. , Oleshko Vladimir P. , Middleton L. Robert , Soles Christopher L. 
Published: February 2020

Polymeric, solid-state, single-ion conducting electrolytes with high ionic conductivity are desired for application in high energy battery platforms. Recently, PEO-based copolymers containing the lithiated STFSI monomer have been investigated for use as single-ion conducting electrolytes in lithium batteries. These polymers exhibit wider electrochemical stability windows and sustain capacity of full cell battery cycling at higher discharge rates relative to traditional polymer electrolytes composed of PEO and a mobile, dopant salt.
This presentation will report on the characterization of the morphology and dynamics of PSTFSI-ran-PEGMA copolymer electrolytes as a function of the monomer ratio (Li+ loading) and length of the polyethylene glycol comb. Structure of the electrolytes is investigated by SAXS/WAXS, SANS, and TEM. Lithium environment is examined using solid state MAS NMR spectroscopy, and ion dynamics are studied via PFG NMR spectroscopy and dielectric spectroscopy. Polymer dynamics are investigated via QENS. Together, this suite of characterization techniques reveals the structure and corresponding Li+ transport mechanisms in this family of high performing PEO-based single ion conductors.
Fluoride-Doped Layered-Spinel Hybrid Lithium-Rich Cathode Material for Lithium Ion Battery
Authors: Yi-Chun Jin 
Published: February 2020

The limitation of theoretical capacity in cathode material is a technological bottleneck for developing next generation lithium ion battery. For this regard, researchers recently focus on lithium-rich composite cathode (1-yLiMn2O3-yLiNixMn1-xO2) due to its high versatility of capacity output ranged from 280 to 320 mAhg-1(usually charge/discharge in 0.1C). In this study, we have proposed a novel design and feasible synthesis of layered-spinel hybrid lithium-rich cathode, modiﬁcation by appreciable fluoride doping. This is the first use of polymeric fluoride as a dopant source in non-aqueous co-precipitation batch. In a detailed structural analysis, spinel phases are spontaneous formed and encapsulated onto the layer matrix after fluoride doping. The electrochemical result shows an extra high voltage charge-discharge character around 4.8V, speculated as LiNi0.5Mn1.5O4 intercalation process. It delivered stable cycleability and improved C-rate performances as compared with the traditional layered cathode. A fast lithiated /delithiated process is attributed to well-distributed 3D diffusivity tunnel in the spinel-embedded Li-rich layer material.

Figure 1
Structural Ambiguity in Li- and Mn-Rich Transition Metal Oxides: Trigonal, Monoclinic, or Both?
Authors: Shukla Alpesh Khushalchand , Ramasse Quentin , Ophus Colin , Duncan Hugues , Chen Guoying , Dahmen Ulrich 
Published: February 2020

Li- and Mn-rich transition metal oxides have been extensively studied recently for their potential application in Li-ion batteries. These materials have attracted a lot of interest due to the high capacity offered by them. However, the structure of these materials in their pristine state is not clearly understood. Several reports have assigned their structure to be trigonal (R-3m), monoclinic (c2/m), or a combination of both (composite). The present study discusses the structure of Li1.2(Ni0.13Mn0.54Co0.13) O2 prepared with two different morphologies: plates and needles, using the results obtained from aberration corrected scanning transmission electron microscopy (STEM) imaging, electron energy loss spectroscopy (EELS) and X-ray energy dispersive spectroscopy (XEDS). 3-dimensional information was obtained by imaging the material at different zone axes and it was found that the primary particles are made up of a single phase, consisting of domains that correspond to variants of monoclinic structure, save for rare localized defects and a thin surface layer on certain crystallographic facets. These findings were further confirmed on two commercially available Li-and Mn-rich transition metal oxides, namely TODA HE5050 and Envia HCMR XLE2 . It will be shown how diffraction-based techniques can lead to ambiguous interpretation of structure in this class of materials. The study not only solves the ambiguity in the structure determination of this class of complex oxides but also highlights the importance of atomic resolution imaging performed on multiple zone axes when it is used for similar investigations.

Figure 1
(Invited) Surface Modification Effect on the First Charging Process over 4.5 V and the Enhancement of Energy of LiNi1/3Co1/3Mn1/3O2
Authors: Sakaebe Hikari , Yano Akira , Shikano Masahiro , Ogumi Zempachi 
Published: February 2020

Surface modification of the positive electrode materials by coating technique with metal oxides, phosphate, and so on is commonly used in these days for stabilizing the electrolyte/positive electrode material interface [1-3]. We can not only extend the battery life, but also have a chance to increase the battery energy by charging to higher voltage by the stabilization.
Authors have developed the sol-gel based coating procedure to make the thin and uniform layer of Al oxide on the commercially available LiNi1/3Co1/3Mn1/3O2 (NCM), by which the decrease of the initial capacity was suppressed [4]. Using this modified NCM, first charging process was precisely investigated electrochemically varying the charge cut-off voltage up to 4.8 V. Below 4.7 V, discharge capacity increased as the charge cut-off voltage was elevated with/without modification. Coulombic efficiency, average voltage, cycling properties were improved by surface modification.
Comparison of AC impedance spectra and dQ/dVof the galvanostatic charge-discharge curves, with the aid of TEM results of the surface region, for modified/bare NCM revealed that the surface of the bare NCM was damaged to be high-resistant in very early stage of first charge, as was observed by surface analysis using synchrotron facilities [5]. Al-oxide modification suppressed the increasing rate of interfacial resistance of Li+ intercalation/deinercalation at the surface.
References
[1] Z. H. Chen, et al., Electrochimica Acta, 49(7), 1079 (2004).
[2] B. C. Park, et. al., Journal of Power Sources, 178(2), 826 (2008).
[3] .A. T. Appapillai, et.al., Chemistry of Materials, 19(23),5748 (2007).
[4] A. Yano, H. Sakaebe, et. al., J. Electrochem. Soc., 162(2), A3137-A3144 (2015).
[5] D. Takamastu, et. al., Angewandte Chemie,
124(46), 11765–11769 (2012).