The Best Defense is No Offense: Reforming Louisiana\u27s Security for Court Costs Statute

The article discusses the security for court costs statute in Louisiana, as well as its history including its use in the early English common law, its comparison to other international jurisdictions, as well as some proposals for reform

A method for measuring the contact area in instrumented indentation testing by tip scanning probe microscopy imaging

The determination of the contact area is a key step to derive mechanical properties such as hardness or an elastic modulus by instrumented indentation testing. Two families of procedures are dedicated to extracting this area: on the one hand, post mortem measurements that require residual imprint imaging, and on the other hand, direct methods that only rely on the load vs. the penetration depth curve. With the development of built-in scanning probe microscopy imaging capabilities such as atomic force microscopy and indentation tip scanning probe microscopy, last generation indentation devices have made systematic residual imprint imaging much faster and more reliable. In this paper, a new post mortem method is introduced and further compared to three existing classical direct methods by means of a numerical and experimental benchmark covering a large range of materials. It is shown that the new method systematically leads to lower error levels regardless of the type of material. Pros and cons of the new method vs. direct methods are also discussed, demonstrating its efficiency in easily extracting mechanical properties with an enhanced confidence

Improving Layer-by-Layer Assembly for Superior Flame Retardant and Gas Barrier Thin Films

Layer-by-layer (LbL) assembly is a promising technique for depositing multi-functional thin films from dilute aqueous solutions. These films have found use as environmentally-benign flame retardants, replacing halogenated flame retardants, and as flexible gas barrier thin films, replacing vacuum-deposited inorganic oxide thin films. Unfortunately, LbL assembly has drawbacks that have not been adequately addressed, such as stiffening of coated substrates and the high number of deposition steps required. Thin films of chitosan and poly(sodium phosphate) were deposited on cotton fabric via LbL assembly to reduce flammability. The fabric was rinsed in an ultrasonication bath between deposition steps to improve the softness (i.e., hand) of the coated fabric. Ultrasonication is believed to remove weakly adhered polyelectrolyte and eliminate bridging of individual fibers, preventing the fabric from becoming stiff while improving the flame retardant behavior. Incorporating amine salts into the cationic polyelectrolyte and its associated rinse enables LbL clay-containing films to achieve large thickness (>1 μm) with relatively few deposition steps. This technique is potentially universal, exhibiting thick growth with multiple types of nanoclay, including montmorillonite and vermiculite, a variety of amine salts (e.g., hexylamine and tris), and a host of cationic polyelectrolytes, such as poly(allylamine) and chitosan. The characteristic ordered structure found in LbL-assembled films is maintained despite the increased thickness. These films display extraordinary gas barrier and flame resistance with fewer than 8 deposition cycles

Development of Composite Sandwich Bonded Longitudinal Joints for Space Launch Vehicle Structures

The NASA Composite Technology for Exploration (CTE) Project is developing and demonstrating critical composite technologies with a focus on composite bonded joints; incorporating materials, design/analysis, manufacturing, and tests that utilize NASAs expertise and capabilities. The project has goals of advancing composite technologies and providing lightweight structures to support future NASA exploration missions. In particular, the CTE project will demonstrate weight-saving, performance-enhancing composite bonded joint technology for Space Launch System (SLS)-scale composite hardware. Advancements from the CTE project may be incorporated as future block upgrades for SLS structural components. This paper discusses the details of the development of a composite sandwich bonded longitudinal joint for a generic space launch vehicle structure called the CTE Point Design. The paper includes details of the design, analysis, materials, manufacturing, and testing of sub-element joint test articles to test the capability of the joint design. The test results show that the composite longitudinal bonded joint design significantly exceeds the design loads with a 2.0 factor of safety. Analysis pre-test failure predictions for all sub-element bonded joint test coupons were all within 10% of the average test coupon failure load. This testing and analysis provides confidence in the potential use of composite bonded joints for future launch vehicle structures

Giant Anomalous Hall Conductivity in the Itinerant Ferromagnet LaCrSb₃ and the Effect of f-Electrons

Itinerant ferromagnets constitute an important class of materials wherein spin polarization can affect the electric transport properties in nontrivial ways. One such phenomenon is anomalous Hall effect which depends on the details of the band structure such as the amount of band crossings in the valence band of the ferromagnet. Here, extraordinary anomalous Hall effect is found in an itinerant ferromagnetic metal LaCrSb3. The rather 2D nature of the magnetic subunit imparts large anisotropic anomalous Hall conductivity of 1250 Ω−1 cm−1 at 2 K. The investigations suggest that a strong Berry curvature by abundant momentum-space crossings and narrow energy-gap openings are the primary sources of the anomalous Hall conductivity. An important observation is the existence of quasi-dispersionless bands in LaCrSb3 which is now known to increase the anomalous Hall conductivity. After introducing f-electrons, anomalous Hall conductivity experiences more than twofold increase and reaches 2900 Ω−1 cm−1 in NdCrSb3. © 2021 The Authors. Advanced Quantum Technologies published by Wiley-VCH Gmb

Giant Topological Hall Effect in the Noncollinear Phase of Two-Dimensional Antiferromagnetic Topological Insulator MnBi₄Te₇

Magnetic topological insulators provide an important platform for realizing several exotic quantum phenomena, such as the axion insulating state and the quantum anomalous Hall effect, owing to the interplay between topology and magnetism. MnBi4Te7 is a two-dimensional Z(2) antiferromagnetic (AFM) topological insulator with a Ne ' el temperature of similar to 13 K. In AFM materials, the topological Hall effect (THE) is observed owing to the existence of nontrivial spin structures. A material with noncollinearity that develops in the AFM phase rather than at the onset of the AFM order is particularly important. In this study, we observed that such an unanticipated THE starts to develop in a MnBi4Te7 single crystal when the magnetic field is rotated away from the easy axis (c-axis) of the system. Furthermore, the THE resistivity reaches a giant value of similar to 7 mu Omega-cm at 2 K when the angle between the magnetic field and the c-axis is 75 degrees. This value is significantly higher than the values for previously reported systems with noncoplanar structures. The THE can be ascribed to the noncoplanar spin structure resulting from the canted state during the spinflip transition in the ground AFM state of MnBi4Te7. The large THE at a relatively low applied field makes the MnBi4Te7 system a potential candidate for spintronic applications

The complex process of scaling the integration of technology enhanced learning in mainstream classrooms

The early optimism for how technology might transform teaching and learning practices in mainstream school classrooms has long faded in many countries around the world. Whilst early research findings suggested that this was due to obvious barriers such as access to the technology itself, more recent attempts to scale student-access have illuminated other factors and provided a more sound theoretical foundation for us to understanding the processes and products of scaling educational technology innovations. This keynote will use findings from key projects and initiatives to highlight what is being learned – and how this might inform future endeavours to realise a more 21st century curriculum

Large Anomalous Hall and Nernst Effects in High Curie-Temperature Iron-Based Heusler Compounds

Abstract The interplay between topology and magnetism has recently sparked the frontier studies of magnetic topological materials that exhibit intriguing anomalous Hall and Nernst effects owning to the large intrinsic Berry curvature (BC). To better understand the anomalous quantum transport properties of these materials and their implications for future applications such as electronic and thermoelectric devices, it is crucial to discover more novel material platforms for performing anomalous transverse transport studies. Here, it is experimentally demonstrated that low-cost Fe-based Heusler compounds exhibit large anomalous Hall and Nernst effects. An anomalous Hall conductivity of 250?750 S cm?1 and Nernst thermopower of above 2 µV K?1 are observed near room temperature. The positive effect of anti-site disorder on the anomalous Hall transport is revealed. Considering the very high Curie temperature (nearly 1000 K), larger Nernst thermopowers at high temperatures are expected owing to the existing magnetic order and the intrinsic BC. This work provides a background for developing low-cost Fe-based Heusler compounds as a new material platform for anomalous transport studies and applications, in particular, near and above room temperature