HMX-based explosives LX-10 and PBX-9501 were heated through the β-δ phase transition. Ultra-small angle x-ray scattering (USAXS) molecular diffraction simultaneously recorded as HMX was heated. Mesoscale voids structure dramatically change promptly with transition, rather than other thermal effects. Also, induced damage, observed in USAXS, occurs more readily at elevated temperatures; such, dose reduced to mitigate this effect. Optical microscopy performed during a similar heating cycle...

Metal additive manufacturing (AM) is a critical capability for Industry 4.0, with particular potential in the aerospace and medical industries. Its ability to create dense metal parts intricate geometries makes it appealing demanding environments requiring specific thermal mechanical properties, as well long-term reliability. Despite its potential, challenges such low surface quality buried porosity have impeded widespread adoption of AM. Therefore, advances real-time monitoring AM processes...

Interfacial force microscopy (IFM) is used to measure the electrical contact properties of electroplated gold thin films type in microelectromechanical system relays. Force and current levels consistent with those present metal-metal switches are examined an atmospheric-pressure, dry-nitrogen ambient at room temperature, nature a nonmetallic contamination layer which limits resistance lifetime explicitly mechanically, electrically chemically. The mechanical on substrate observed by IFM both...

We correlate topography and diffraction measurements to demonstrate that grain orientation profoundly influences polishing rates in polycrystalline diamond synthesized by chemical vapor deposition. Grains oriented with {111} or {100} planes perpendicular the surface normal polish at significantly lower compared grains of all other orientations when is polished continuously varying in-plane directions. These observations agree predictions periodic bond chain vector model, developed previously...

We investigate the interactions of Pluronics L61 and L64 with a dioleylphosphatidylcholine (DOPC) lipid bilayer by atomistic molecular dynamics simulations using all-atom OPLS force field. Our results show that initial configuration polymer respect to determines its final conformation within bilayer. When is initially placed at lipid/water interface, we observe partial insertion in U-shaped conformation. On other hand, when centered bilayer, it stabilizes transmembrane state, which...

AbstractDiamond has a unique combination of physical properties for the inertial confinement fusion ablator application, such as appropriate optical properties, high atomic density, yield strength, and thermal conductivity. Here, we present feasible concept fabrication diamond shells. The capsules is multi-step process which involves chemical vapor deposition on silicon mandrels followed by polishing, microfabrication holes, removing mandrel an etch process. We also discuss pros cons...

This work links the structural and electrical properties of thin polycrystalline silicon films at level individual grains. A four point “transparent probe” technique was developed which allowed a small number grains to be isolated measured electrically in test structures can nondestructively prepared for direct imaging transmission electron microscope (TEM). By measuring temperature dependence resistance many structures, distribution grain boundary activation energies determined. After...

We present a coarse-grained MARTINI model for methylene blue (MB) and investigate the interactions of MB with dioleylphosphatidylcholine (DOPC) lipid bilayers by molecular dynamics simulations. Our results show that charge state oxidation degree DOPC bilayer play critical roles on membrane properties. Oxidation significantly increases permeability water molecules, irrespective MB. The most significant changes in properties are obtained peroxidized presence cationic MB, ∼11% increase area per...

Edge characterization has become increasingly important in nanotechnology due to the growing demand for precise nanoscale structure fabrication and assembly. detection is often performed by thresholding spatial information of a top-down image obtained scanning electron microscopy or other surface techniques. Results are highly dependent on an arbitrary threshold value, which makes it difficult reveal nature real compare results among images. In this paper, we present alternative edge...

Intra- and inter-layer integrity of components fabricated with advanced manufacturing techniques, such as laser powder bed fusion, is dependent upon rapid heating, melting, solidification processes. There a need for new techniques to provide in situ feedback these Here laser-based ultrasonic technique probe thermal effects induced by high-power continuous wave titanium samples described. Numerical simulations were performed show that, spatially uniform heating beam, laser-induced surface...

We have proposed and validated a true hybrid SET/CMOS device, called SETMOS, that is able to extend the Coulomb blockade oscillations of SET transistor into /spl mu/A current range, corresponding near sub-threshold operation region nanometer-scale MOSFET. New nano-scale analog applications, working at sub-ambient temperatures (-150/spl deg/C up 100/spl deg/C), including novel NDR circuit, amplifiers, even NEMS-SETMOS circuit cells are uniquely supported by SETMOS.

Molecular dynamics (MD) and Monte Carlo (MC) simulations were applied together for the first time to reveal porous structure transformation mechanisms of mesoporous silica MCM-41 subjected temperatures up 2885 K. Silica was experimentally characterized inform models enable prediction changes in gas adsorption/separation properties. MD suggest that pore closure process is activated by a collective diffusion matrix atoms into region, accompanied bond reformation at surface. Degradation...

Advanced manufacturing techniques, such as additive manufacturing, enable the design of increasingly complex components for a wide range industrial applications. However, this complexity makes qualification parts, determining whether part is within some margin error from initial design, difficult. To inspect and qualify internal geometries that are not accessible with an external probe, parts typically scanned computed tomography (CT), manually compared to computer-aided (CAD) model using...

Visible light-based volumetric additive manufacturing (VAM) technology has recently enabled rapid 3D printing of optically transparent resins in a single step. There is now strong interest extending the design space VAM to include opaque, scattering and composite materials. Microwave energy can penetrate more deeply than visible light into broader family For microwaves be useful for VAM, however it necessary have fundamental understanding material dielectric properties, microwave field...

Millimeter sized arrays of uniformly-distributed nanopores (180–220 nm) were created in thin (200 silicon nitride membranes using interferometric lithography. Molecular transport properties the fabricated devices investigated experimentally and compared with those state-of-the-art polycarbonate track etched membranes. Two similarly-sized proteins, bovine serum albumin (BSA) hemoglobin (BHb), used as permeates experiments. Up to 40 fold higher pore fluxes achieved unmodified relative thicker...

Hollow spherical ZnO particles doped with Ag were synthesized a two-step oxidation and sublimation furnace annealing process. nanoparticle precipitates, as observed by transmission electron microscopy, present in the polycrystalline matrix at concentrations below 0.02 mol%, significantly 0.8 mol% solubility limit for ZnO. Enhanced Raman scattering of phonon modes is observed, increasing concentration. A further enhancement due to resonance effects was LO phonons excited 2.33-eV photons...

Abstract Structures formed by advanced manufacturing methods increasingly require nondestructive characterization to enable efficient fabrication and ensure performance targets are met. This is especially important for aerospace, military, high precision applications. Surface acoustic waves (SAW) generated laser-based ultrasound can detect surface sub-surface defects relevant a broad range of processes, including laser powder bed fusion (LPBF). In particular, an all-optical SAW generation...

Laser ultrasonics is a remote nondestructive evaluation technique suitable for real-time monitoring of fabrication processes in semiconductor metrology, advanced manufacturing, and other applications where non-contact, high fidelity measurements are required. Here we investigate laser ultrasonic data processing approaches to reconstruct images subsurface side drilled holes aluminum alloy specimens. We demonstrate through simulation that the model-based linear sampling method (LSM) can...

Electroplated gold surfaces of the type used for MEMS switches were surveyed by atomic force microscopy (AFM) to define surface topographical features, and x-ray photoelectron spectroscopy (XPS) determine chemical composition contact surface. The contacted with electrochemically sharpened tungsten probes using an interface microscope (IFM), capable simultaneously measuring currents from 10 fA mA forces ranging 0.01 100 uN. Both attractive repulsive observed, on probe tip found exist at...

We describe a hot-filament chemical vapor deposition process for growing freestanding nanostructured diamond films, ∼80μm thick, with residual tensile stress levels ≲90MPa. characterize the film microstructure, mechanical properties, bond distribution, and elemental composition. Results show that our films are columnar grain diameters of ≲150nm highly variable length along growth direction ∼50–1500nm. These have rms surface roughness ≲200nm 300×400μm2 scan, which is about one order magnitude...

<para xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> InGaN quantum well structures on GaN epilayers were exposed to 500 keV alpha particles fluences above <formula formulatype="inline"> <tex Notation="TeX">${\hbox {10}}^{14}$</tex></formula> cm<formula Notation="TeX">$^{2}$</tex></formula> probe the relative radiation tolerance of epilayer and wells. Performance was estimated by intensity ion-beam induced luminescence. Two separate types emitted at...