Lifeboat Foundation

Nice find on nanoparticles and energy transfer — important in scalable devices, energy conservation, etc.

The development, design and the performance evaluation of rare-earth doped host materials is important for further optical investigation and industrial applications. Herein, we successfully fabricate KLu₂F₇ upconversion nanoparticles (UCNPs) through hydrothermal synthesis by controlling the fluorine-to-lanthanide-ion molar ratio. The structural and morphological results show that the samples are orthorhombic-phase hexagonal-prisms UCNPs, with average side length of 80 nm and average thickness of 110 nm. The reaction time dependent crystal growth experiment suggests that the phase transformation is a thermo-dynamical process and the increasing F⁻/Ln³⁺ ratio favors the formation of the thermo-dynamical stable phase — orthorhombic KLu₂F₇ structure. The upconversion luminescence (UCL) spectra display that the orthorhombic KLu₂F₇:Yb/Er UCNPs present stronger UCL as much as 280-fold than their cubic counterparts. The UCNPS also display better UCL performance compared with the popular hexagonal-phase NaREF₄ (RE = Y, Gd). Our mechanistic investigation, including Judd-Ofelt analysis and time decay behaviors, suggests that the lanthanide tetrad clusters structure at sublattice level accounts for the saturated luminescence and highly efficient UCL in KLu₂F₇:Yb/Er UCNPs. Our research demonstrates that the orthorhombic KLu₂F₇ is a promising host material for UCL and can find potential applications in lasing, photovoltaics and biolabeling techniques.

Magnetohydrodynamics involves magnetic fields (magneto) and fluids (hydro) that conduct electricity and interact (dynamics). MHD technology is based on a fundamental law of electromagnetism: When a magnetic field and an electric current intersect in a liquid, their repulsive intersection propels the liquid in a direction perpendicular to both the field and the current.

What happens when your power lines get all kinds of trash hanging from them and it’s not safe to send up a human? In Xiangyang, China, you send in the drones. Specifically, the drones that shoot fire.

https://www.youtube.com/watch?v=IEWBmIrXyhw

“Launched in 2007, the Fuller Challenge has defined an emerging field of practice: the whole systems approach to understanding and intervening in complex and interrelated crises for wide-scale social and environmental impact. The entry criteria have established a new framework through which to identify and measure effective, enduring solutions to global sustainability’s most entrenched challenges. The rigorous selection process has set a unique standard, gaining renown as “Socially-Responsible Design’s Highest Award.”

The Fuller Challenge attracts bold, visionary, tangible initiatives focused on a well-defined need of critical importance. Winning solutions are regionally specific yet globally applicable and present a truly comprehensive, anticipatory, integrated approach to solving the world’s complex problems.”

Deadline is March 31, 2017

Planentary magnetic fields how do they work —

Astonishing geomagnetic spike hit the ancient kingdom of Judah.

If this were to happen again today, the electrical grid could be a smoking ruin.

Continue reading “Astonishing geomagnetic spike hit the ancient kingdom of Judah” »

Science mimicking nature’s dew in a lab. Important btw in how we looking at H₂O harvesting and improving how we advance green energy; however, I see usage of this research in other emerging technologies as well.

Understanding how droplet condensation happens plays an essential role for our fundamental insights of wetting behaviors in nature and numerous applications. Since there is a lack of study of the initial formation and growing processes of condensed droplets down to nano-/submicroscale, relevant underlying mechanisms remain to be explored. We report an in situ observation of vapor condensation on nano-/microtextured superhydrophobic surfaces using optical microscopy. An interesting picture of the vapor condensation, from the initial appearance of individual small droplets (≤1 μm) to a Cassie-Baxter wetting state (30 μm), are exhibited. It is found that individual droplets preferentially nucleate at the top and the edge of single micropillars with very high apparent contact angles on the nanotextures. Scenarios of two distinguished growing modes are reported statistically and the underlying mechanisms are discussed in the view of thermodynamics. We particularly reveal that the formation of the Cassie-Baxter wetting state is a result of a continuous coalescence of individual small droplets, in which the nanotexture-enhanced superhydrophobicity plays a crucial role. We envision that these fundamental findings can deepen our understanding of the nucleation and development of condensed droplets in nanoscale, so as to optimize design strategies of superhydrophobic materials for a broad range of water-harvesting and heat-transfer systems.

(Phys.org)—Researchers have developed a type of rechargeable battery called a flow cell that can be recharged with a water-based solution containing dissolved carbon dioxide (CO₂) emitted from fossil fuel power plants. The device works by taking advantage of the CO₂ concentration difference between CO₂ emissions and ambient air, which can ultimately be used to generate electricity.

The new flow cell produces an average power density of 0.82 W/m, which is almost 200 times higher than values obtained using previous similar methods. Although it is not yet clear whether the process could be economically viable on a large scale, the early results appear promising and could be further improved with future research.

The scientists, Taeyong Kim, Bruce E. Logan, and Christopher A. Gorski at The Pennsylvania State University, have published a paper on the new method of CO₂-to-electricity conversion in a recent issue of Environmental Science & Technology Letters.

Engineers at the U.S. Army Armament Research, Development and Engineering Center, or ARDEC, have been making advancements in an initiative called “Component Miniaturization.”

Its mission focuses on making armament systems more precise, energy efficient, scalable and effective by reducing the size of critical components in sub-systems such as safe and arm devices, electronics packages, power supplies and inertial measurement systems. Size reductions in one sub-system can have a positive effect on another. For example, a smaller and more efficient electronics package design can reduce power supply demands as well as reduce the need for heavier supporting structures. The space savings and mass savings could then be used to add a larger explosive warhead or increase control surfaces for additional maneuverability. The reduced size and mass could also allow for additional portability to smaller calibers or to systems with greater launch velocities.

The initiative involves several discrete projects, some of which are described below:

Continue reading “Smaller and smarter MEMS and electronics for bullets that can monitor a building during urban warfare” »

A purely organic p–n junction is used as the luminescent center in a novel planar device that exhibits a high external quantum efficiency and an extremely low driving voltage.

In recent years, organic LEDs (OLEDs) have become a popular option for creating digital displays. These devices generally consist of three types of semiconductors (i.e., a p-type hole-transport layer, an n-type electron-transport layer, and an emission layer).^1–3 The emission layer (normally capable of bipolar transport) provides a platform for carrier capture, exciton generation, and transition, and the luminescent property of an OLED mainly depends on the fluorescence behavior of single-molecule emitters. However, the incorporation of the emission layer within the structure of an OLED causes two energy barriers to be induced at the interfaces with the emission and transport layers. This means that the driving voltages for OLEDs are generally much larger than for traditional inorganic LEDs (with similarly chromatic emission). Moreover, the excitons that are generated at most purely organic emitters have a strong binding energy.

Continue reading “Realizing high-performance and low-cost fluorescent organic LEDs” »