X-ray fluorescence mapping: Insights into mesoscale structure impact on battery functional electrochemistry

Electron transfer and ion transport occurs over multiple-length scales ranging from the atomic to mesoscale within battery materials and electrodes. Micro-X-ray fluorescence (µ-XRF) is an important characterization tool as it can resolve structural, compositional, and redox information while providing insight into the spatial distribution of an electroactive material. In this work, µ-XRF mapping is used to probe the distribution of iron within thin planar slurry-based and thick porous carbon nanotube (CNT)-based magnetite (Fe3O4) electrodes. Notably, the porous CNT-based electrode showed homogenous distribution of Fe within the electrode whereas the planar electrode demonstrated distinct Fe aggregates. This information was used to rationalize the electrochemistry observed by cyclic voltammetry and galvanostatic cycling. The thick porous electrode delivered 215% more capacity per gram of magnetite during the first discharge, consistent with increased electrode homogeneity enabling effective ion access and electron transfer. Graphical Abstract

Effect of the Shape of Rolling Passes and the Temperature on the Corrosion Protection of the Mg/Al Bimetallic Bars

The paper presents the results of experimental tests of the rolling process of Mg/Al bimetallic bars in two systems of classic passes (horizontal oval-circle-horizontal oval-circle variant I) and modified (multi-radial horizontal oval-multi-radial vertical oval-multi-radial horizontal oval-circle-variant II). The feedstock in the form of round bimetallic bars with a diameter of 22 mm and 30% of the outer aluminum layer was made through explosive welding. The bimetallic bars consisted of an AZ31 magnesium core and a 1050A aluminum outer layer. Bars with a diameter of 17 mm were obtained as a result of rolling in four passes. The rolling process in the passes was conducted at two temperatures of 300 and 400 °C. Based on the analysis of the test results, it was found that the use of modified passes and a lower rolling temperature (300 °C) ensures a more homogenous distribution of the plating layer around the circumference of the core and results in an even grain decreasing, which improves the corrosion resistance of bimetallic bars compared to rolling bars in a classic system of passes and at a higher temperature (400 °C).

Influence of hybrid pin profile on microstructural and mechanical properties of Al/SiC graded composites produced by friction stir processing

Friction stir processing (FSP) was employed to fabricate a surface graded composite by embedding SiC reinforcement particles in an AA6082-T6 matrix. Conical blind holes were drilled on the surface of the plate with varying inter-hole distances. The processing was performed with the different number of passes by keeping rotational and traverse speed constant. A new hybrid tool with a combination of conventional conical threaded tool and the triangular cross-sectioned tool was used in processing. The microstructural features of the processed samples were examined by a 3D microscope and scanning electron microscope (SEM). Mechanical properties such as microhardness, tensile strength was thoroughly evaluated. It is reported that the number of passes played an essential role in the distribution of reinforcement particles and grain refinement. The hardness value improved by applying multiple passes. The fractured tensile samples showed ductile failure. The sample treated with double passes gave better results with the homogenous distribution of reinforcement particles compared to samples processed with a single pass.

ACCURACY VALIDATION OF TILTED CAMERA SETUPS IN OPEN SKIES PROJECT AND MAPPING APPLICATIONS

Signed March 24, 1992, the Open Skies Treaty permits each state-party to conduct short-notice, unarmed, reconnaissance flights over the others' entire territories to collect data on military forces and activities. Observation aircraft equipped with sensors shall enable the observing party to identify significant military equipment. The Open Skies Treaty agreed on an observation of 30cm GSD. Based on 8 mid-format cameras for 3 flight levels, a system was adjusted to comply with the regulations. However, the overall aim was to also use the system for mapping purposes in Romania, specifically the medium altitude configuration. From this medium altitude configuration, one specific combination raised our interest. The designed wide corridor mapping system, using two RGB tilted cameras and one RGB nadir camera generates a certain range of resolution of the sideward looking tilted cameras and a non-homogenous distribution of the GSD in the overlapping areas. While a reduction of the GSD in the remote parts of the tilted cameras is a well-known and accepted fact, the effect in the overlap of the tilted cameras with the nadir one is the opposite mathematically. In some cases, such an effect can cause a better GSD in these areas than expected.

Research on Microstructure and Refining Performance of Al-Ti-C Grain Refiner Prepared by Ultrasonic Coupling

The application of ultrasonic field in the preparation of Al-Ti-C refiners can lead to the the homogenous distribution of the second phase TiAl3 and the particle phase TiC in the matrix, thus enhancing the refinement effect. In this paper, the Al-Ti-C grain refiner was successfully prepared by the ultrasonic coupling method, and its microstructure was observed. The prepared refiner was added to pure Al to verify the refining performance, and the refining mechanism was analyzed. The results indicate that the Al-Ti-C grain refiner prepared by ultrasonic field has excellent refining performance, which reduces the grain size of Al to 100 μm, and the optimum activation refining time is 3 min. The reason is that the morphology and size of the second phase TiAl3 and TiC in Al-Ti-C are changed by cavitation effect, acoustic streaming effect and thermal effect caused by high intensity ultrasonic, and the α-Al nucleates effectively under the synergistic of TiC and TiAl3 particles.

Is hypertensive left ventricular hypertrophy a cause of sustained ventricular arrhythmias in humans?

Sudden cardiac death (SCD) is most commonly secondary to sustained ventricular arrhythmias (VAs). This review aimed to evaluate if left ventricular hypertrophy (LVH) secondary to systemic hypertension in humans is an isolated risk factor for ventricular arrhythmogenesis. Animal models of hypertensive LVH have shown changes in ion channel function and distribution, gap junction re-distribution and fibrotic deposition. Clinical data has consistently exhibited an increase in prevalence and complexity of non-sustained VAs on electrocardiographic monitoring. However, there is a dearth of trials suggesting progression to sustained VAs and SCD, with extrapolations being confounded by presence of co-existent asymptomatic coronary artery disease (CAD). Putatively, this lack of data may be due to the presence of more homogenous distribution of pathophysiological changes seen in those with hypertensive LVH versus known pro-arrhythmic conditions such as HCM and myocardial infarction. The overall impression is that sustained VAs in the context of hypertensive LVH are most likely to be precipitated by other causes such as CAD or electrolyte disturbance.

Effect of nanostructured Cu on microstructure, microhardness and wear behavior of Cu-xGnP composites developed using mechanical alloying

In the present study, Cu-1, 2 and 3 wt.% xGnP composites have been developed by powder metallurgy (PM) route using nanostructured Cu powder and their effect on microstructure, microhardness, sliding wear behaviour has been examined. The crystallite size and lattice strain of Cu after 25 h of mechanical milling have been found to be 16 nm and 0.576%, respectively. Major challenges associated with the development of Cu-xGnP composites is the uniform dispersion of the nanoplatelets in the Cu matrix, which have been dealt out by incorporating the nanostructured Cu- xGnP composites after mechanical alloying leading to the homogenous distribution of nanoplatelets in the Cu-matrix. A significant enhancement in relative density, microhardness and wear resistance of the Cu-3 wt. % xGnP nanofiller composite in particular has been observed due to the uniform distribution of the nanofillers. In Cu-3 wt. % xGnP composite developed using as-milled nanostructured Cu, a microhardness of ∼ 1.1 GPa could be achieved which is about ∼3 times higher than that of the pure sintered Cu sample (∼359 MPa). Nanostructured Cu also leads to enhancement of the hardness and wear property as compared to the as-received Cu. The wear mechanism in the various nanostructured Cu-xGnP composites has been studied in details.

Mapping the Chiroptical Properties of Local Domains in Thin Films of Chiral Silicon Phthalocyanines by CD Imaging

The first example of uniformly chiral thin films of silicon phthalocyanines (SiPcs) are reported. The local domains of the films are mapped using circular dichroism (CD) imaging (CDi) technique available at the Diamond B23 beamline. The CDi allowed us to increase the spatial resolution up to 525× when compared with benchtop spectrometers. The results indicate formation on-surface of chiral and stable supramolecular assemblies with homogenous distribution. Chemical functionalization and solvent choice for deposition allow controllable chiroptical properties to be obtained. The method and technique reported in this work could be applied to prepare and characterize a wide variety of chiral thin films.

An Analysis of the Effects of Livestock Support Policies on Breeders: An Example of TR83 Region in Turkey

This paper studied the effect of livestock support policies applied in Turkey by a emprical study. The study was carried out based on the analysis of the data collected through surveys with a total of 478 livestock enterprises in the TR83 region (including Amasya, Çorum, Samsun and Tokat provinces). The enterprises included in the survey study were grouped into three categories by the number of their animals. Binary Logistic Regression Model was applied in order to define the policy-based support payment utilization probabilities of the enterprises and the factors affecting them. It was determined that approximately 45% of the enterprises cannot utilize livestock supports. The most utilized support items by the enterprises were determined as calf support, support per animal, forage plant support and raw milk support. A total of 65% of the enterprise owners think that the support amount per animal is insufficient, but regard the mentioned support item as the most important factor for improving animal presence. The utilization rates vary in terms of enterprise scales on the other hand. The support utilization likelihood of medium-scale enterprises is 3.1 times higher than small-scale enterprises, and this likelihood is 1.7 times higher for big-scale enterprises when compared with medium-scale enterprises. The study recommends that some regulations are needed in support of policies to enable a better improvement in animal presence and a homogenous distribution of support payments.

Mechanical performance of co-deposited immiscible Cu–Ta thin films

The immiscible alloy Cu–Ta has the potential for enhanced mechanical performance in applications as a functional coating. To establish baseline mechanical properties, four Cu–Ta films were co-sputtered at the temperatures 23, 400, 600, and 800 °C and tested with nanoindentation at strain rates 5 $$\times $$ × 10−3 s−1 to 10 s−1. Each film had a unique microstructure morphology. The hardness and elastic modulus of the four films were insensitive to strain rate changes. Instead, the measured properties were spatially dependent, particularly in the 600 and 800 °C films. In those two films, there is a bimodal deformation behavior due to Cu-agglomeration under protruding grains and planar Ta-rich regions. Increasing the indentation depth revealed shear band suppression which is related to a homogenous distribution of flow stresses for all four microstructure morphologies. Finally, the Cu–Ta hardness appeared to follow a rule-of-mixtures when compared to extrapolated data of Cu and Ta monolithic films.