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Carbon nanotubes (CNTs) were produced from waste face masks and non-recyclable mixed plastic waste via pyrolysis-chemical vapor deposition (CVD). The yield and properties of the prepared CNTs depended on the feedstock and catalyst used. CoMo/MgO and FeMo/MgO were proven suitable catalysts for producing few-walled and multi-walled CNTs, respectively, regardless of the feedstock. Both mask waste and the FeMo/MgO catalyst led to excellent carbon yield (516.7 wt%) and CNT purity (97.9 wt%). The resulting CNTs were mixed with LiNi0.8Co0.1Mn0.1O2 (NCM811) active material and poly(vinylidene fluoride) binder to fabricate cathodes. Electrochemical measurements showed that CNTs grown on the FeMo/MgO catalyst outperformed commercial carbon black and CNTs. C1–C3 hydrocarbons and H2 present in the plastic pyrolysis gas can be directly used for CNT production without gas separation or purification, therefore, the proposed pyrolysis-CVD process is favorable for efficient plastic upcycling and advanced battery applications. [ABSTRACT FROM AUTHOR]

We present a novel analysis for cluster cosmology that fully forward models the abundances, weak lensing, and the clustering of galaxy clusters. Our analysis notably includes an empirical model for the anisotropic boosts impacting the lensing and clustering signals of optical clusters. These boosts arise from a preferential selection of clusters surrounded by anisotropic large-scale structure, a consequence of the limited discrimination between line-of-sight interlopers and true cluster members offered by photometric surveys. We validate our analysis via a blind cosmology challenge on mocks, and find that we can obtain tight and unbiased cosmological constraints without informative priors or external calibrations on any of our model parameters. We then apply our analysis on the SDSS redMaPPer clusters, and find results favoring low Ωm and high σ8, combining to yield the lensing strength constraint |$S_8 = 0.715_{-0.021}^{+0.024}$|⁠. We investigate potential drivers behind these results through a series of post-unblinding tests, noting that our results are consistent with existing cluster cosmology constraints but clearly inconsistent with other CMB/LSS based cosmology results. From these tests, we find hints that a suppression in the cluster lensing signal may be driving our results. [ABSTRACT FROM AUTHOR]

Linear astigmatism of a confocal off-axis reflective imaging system when the object plane is tilted and located at a finite distance from the imaging system is derived. We show that linear astigmatism can be eliminated by proper configuration of the parent mirror axes in confocal off-axis two-mirror systems. The tilt angle of the image plane is also derived. The developed theory is verified by ray-tracing analysis of an example system. OCIS codes: 080.1010, 110.3960, 220.2740.

We propose a new intuitive metric for evaluating the tension between two experiments, and apply it to several data sets. While our metric is non-optimal, if evidence of tension is detected, this evidence is robust and easy to interpret. Assuming a flat Lambda cold dark matter (ΛCDM) cosmological model, we find that there is a modest 2.2σ tension between the Dark Energy Survey (DES) Year 1 results and the Planck measurements of the cosmic microwave background. This tension is driven by the difference between the amount of structure observed in the late-time Universe and that predicted from fitting the Planck data, and appears to be unrelated to the tension between Planck and local estimates of the Hubble rate. In particular, combining DES, baryon acoustic oscillations, big bang nucleosynthesis, and supernovae measurements recover a Hubble constant and sound horizon consistent with Planck , and in tension with local distance–ladder measurements. If the tension between these various data sets persists, it is likely that reconciling all current data will require breaking the flat ΛCDM model in at least two different ways: one involving new physics in the early Universe, and one involving new late-time Universe physics. [ABSTRACT FROM AUTHOR]

An optical cluster finder inevitably suffers from projection effects , where it misidentifies a superposition of galaxies in multiple haloes along the line of sight as a single cluster. Using mock cluster catalogues built from cosmological N -body simulations, we quantify the impact of these projection effects with a particular focus on the observables of interest for cluster cosmology, namely the cluster-lensing and the cluster-clustering signals. We find that 'observed' clusters, i.e. clusters identified by our cluster finder algorithm, exhibit lensing and clustering signals that deviate from expectations based on a statistically isotropic halo model – while both signals agree with halo model expectations on small scales, they show unexpected boosts on large scales by up to a factor of 1.2 or 1.4, respectively. We identify the origin of these boosts as the inherent selection bias of optical cluster finders for clusters embedded within filaments aligned with the line of sight and show that a minority (⁠|$\sim 30{{\ \rm per\ cent}}$|⁠) of such clusters within the entire sample is responsible for this observed boost. We discuss the implications of our results on previous studies of optical cluster, as well as prospects for identifying and mitigating projection effects in future cluster cosmology analyses. [ABSTRACT FROM AUTHOR]

Hydrogen-induced degradation in Pb(Zr[sub χ]Ti[sub 1-χ])O[sub 3] (PZT) thin film capacitors is investigated in terms of three process parameters, such as electrode structures (Pt/PZT/Pt and Ir/IrO[sub 2]/PZT/Pt/IrO[sub 2]), Zr/Ti compositional ratios (60/40, 53/47, 40/60, 30/70), and the domain poling states ( ± 5 V). It was found that the hydrogen-induced degradation is enhanced when PZT films have high Ti portion, and can be suppressed by domain poling prior to the hydrogen anneal. From secondary ion mass spectroscopy analysis, it can be concluded that the hydrogen-induced degradation originates mainly from the interface of PZT and Pt electrodes. Hysteresis loop shifts in PZT capacitors indicate that negative charge develops at interfaces by the hydrogen anneal. Chemically, hydrogen-induced degradation can be elucidated as the formation of negatively charged hydroxyl group (OH[sup -]). [ABSTRACT FROM AUTHOR]

Silicon dioxide was deposited on a Pt/Pb(Zr[sub x]Ti[sub 1-x])O[sub 3]/Pt capacitor by the plasma-enhanced chemical-vapor deposition (PECVD) method. We have been investigated the mechanism of blister formation on the PECVD SiO[sub 2]/Pt/PZT/Pt capacitor. The blisters were observed at the temperature of 325 °C in O[sub 2] atmosphere, while in N[sub 2] and Ar atmosphere blisters were not formed even at 500 °C. Hydrogen evolution analysis from the PECVD SiO[sub 2] layer showed a sharp peak near 320 °C. The results indicated that the accumulation of water-vapor pressure developed by chemical reaction between oxygen and hydrogen could be the dominant mechanism of blister formation in PECVD SiO[sub 2]/Pt/PZT/Pt capacitors. © 2001 American Institute of Physics. [ABSTRACT FROM AUTHOR]

Presents information on a study which designed a wet cleaning solution to eliminate nonferroelectric phases such as pyrochlore, lead oxide and the etching damaged layer. Methodology; Results; Conclusion.

Adverse interactions between police and the public hurt police legitimacy, cause harm to both officers and the public, and result in costly litigation. Early intervention systems (EISs) that flag officers considered most likely to be involved in one of these adverse events are an important tool for police supervision and for targeting interventions such as counseling or training. However, the EISs that exist are not data-driven and based on supervisor intuition. We have developed a data-driven EIS that uses a diverse set of data sources from the Charlotte-Mecklenburg Police Department and machine learning techniques to more accurately predict the officers who will have an adverse event. Our approach is able to significantly improve accuracy compared with their existing EIS: Preliminary results indicate a 20% reduction in false positives and a 75% increase in true positives. [ABSTRACT FROM AUTHOR]

In this paper, we propose a method of elaborating and detecting brain tumor from MRI suitable for information sharing via the internet for a healthcare provider. This method allows for reducing image sizes without reducing the information content of the images in terms of detecting tumors. The proposed method involves first clarifying the brain tumor area using a modified K-means clustering method and initial segmentation using mean shift segmentation. Then a threshold setting is used to convert the gray scale image and remove noise by applying an erode operation. Finally, the brain tumors in the images are detected using a watershed algorithm. The proposed method was compared with two well-known methods namely the conventional K-mean clustering and Fuzzy C Means (FCM) clustering. We verified the precision and the objectivity of our proposed method. The average precision and recall for our proposed method were excellent with values of 0.914052 and 0.995641, respectively. Our method detected more brain tumors than the conventional K-means clustering and FCM clustering methods and was able to provide for an efficient image data processing with reduced file sizes. [ABSTRACT FROM AUTHOR]

The aviation fuel, jet propellant-8, was applied to premixed charge ignition combustion as well as conventional combustion in a single-cylinder diesel engine and was compared with diesel fuel. The engine performance and emissions were tested with and without exhaust gas recirculation under two operating conditions. The liquid- and vapor-phase penetration of diesel fuel and jet propellant-8 were also compared by Mie-scattering and Schlieren method under evaporating conditions using a constant-volume chamber. It was observed that jet propellant-8 exhibited slightly longer vapor-phase penetration and evidently shorter liquid-phase penetration compared with diesel fuel due to the lower distillation temperature and density of jet propellant-8. However, despite the faster evaporation rate of jet propellant-8, it was found that the ignition delay with jet propellant-8 was 2–3 crank angle degrees longer than that with diesel fuel due to its lower cetane number. This result was consistent for all operating conditions and combustion regimes. Jet propellant-8 also showed lower nitrogen oxides (NOx) and smoke emissions for both combustion regimes under the low-load condition because of locally leaner air–fuel mixture caused by longer ignition delay, higher volatility, and lower aromatic contents. As the engine load increased, jet propellant-8 emitted more NOx under conventional combustion regime due to the more vigorous premixed burn phase compared with diesel fuel. With exhaust gas recirculation, jet propellant-8 showed an improved trade-off relationship between NOx and smoke emissions for both combustion regimes due to its better evaporation characteristics and lower aromatic contents. Premixed charge ignition combustion with jet propellant-8 emitted lower smoke than conventional combustion with jet propellant-8 under near-zero NOx level. [ABSTRACT FROM PUBLISHER]

We simulate resistance distributions of multilevel oxide bipolar resistive random access memories (ReRAMs) through a physical model with Monte Carlo method. The model is used to explain frequently noticed proportionality relationship between distributions of resistances and multi-levels program voltages. By comparing with the experimental results obtained with TaOx/Ta2O5 bipolar ReRAM, the model is verified to have a good consistency with experiments not only qualitatively but also quantitatively. We demonstrate that the resistance distributions responses are basically determined by the ion migration barrier in the resistance varying thin oxide layer which means that it is a nearly intrinsic material property. [ABSTRACT FROM AUTHOR]

The adsorption of charged dendrigraft (arborescent) copolymers of different generations (G1, G2) and side chain molecular weights (Mn ≈ 5000 or 30,000) on silica surfaces in water, was monitored by the quartz crystal microbalance dissipation (QCM-D) technique. The topology of the adsorbed copolymers on mica was also investigated by AFM measurements. The PS-P2VP [polystyrene-graft-poly(2-vinylpyridine)] copolymers readily interact with a silica or mica surface and form a thin layer in acidic water (pH 2) due to the positively charged P2VP shell branches. The adsorbed arborescent PS-P2VP films expanded and collapsed reversibly in water upon cycling between low and high pH values, respectively. As the generation number increased, the density of copolymer molecules adsorbed onto the surface decreased due to stronger intermolecular electrostatic repulsions. The adsorption density also decreased significantly for copolymers with longer P2VP chains due to their more expanded conformation on the surface. [ABSTRACT FROM AUTHOR]