Lifeboat Foundation

Powders of samples were weighed into precleaned Savillex beakers and dissolved with mixtures of 22 M HF and 14 M HNO₃ acids in a 2:1 volume ratio. The modern OIBs and four reference materials (that is, BHVO-2, BCR-2, AGV-2 and BIR-1) were digested on a hot plate at 120 °C for four days. Note that all chondrite and Archaean ultramafic/mafic rock samples were digested in Parr bomb vessels at 220 °C for three days to ensure full dissolution of refractory phases. Dissolution of the dried samples in 5–10 ml 6 M HCl at 120 °C and evaporation was carried out several times to decompose the fluorides formed from HF digestion until clear solutions were obtained. An aliquot of each sample was taken and spiked with a prepared ⁴⁷ Ti–⁴⁹ Ti double spike to determine in advance the Ti concentration using an iCAP RQ inductively coupled plasma mass spectrometer at the Centre for Star and Planet Formation (StarPlan) at the University of Copenhagen. Afterwards, aliquots containing 6 µg Ti were taken and mixed with a ⁴⁷ Ti–⁴⁹ Ti double spike as described previously in ref. ³⁴. The dried mixtures were dissolved with 6 M HCl at 120 °C overnight to ensure sample–spike equilibration.

Titanium was separated from matrix elements following a three-step purification protocol using AG1x8 (200–400 meshes) and DGA resins^34,68, that is, first to separate Fe with 6 M HCl elution on AG1x8 columns, second to remove most of the major and trace elements through 12 M HNO₃ elution and to collect Ti with Milli-Q H₂O on DGA columns and third to purify Ti from the remaining matrix elements with 4 M HF cleaning on AG1x8 columns. An extra DGA pass can be carried out to remove trace amounts of Ca and Cr in the final Ti cuts. To destroy the resin particles and organics from column chemistry, the Ti cuts were treated with 14 M HNO₃ at 120 °C before storage in 0.5 M HNO₃ + 0.01 M HF acids.

Titanium isotopic compositions of the purified samples were measured using the ThermoFisher Scientific Neoma Multicollector ICP-MS. Sample solutions with 500–800 ppb Ti dissolved in 0.5 M HNO₃ + 0.01 M HF were introduced into the multicollector inductively coupled plasma source mass spectrometer by means of an APEX HF desolvating nebulizer from Elemental Scientific and a sapphire injector was used instead of the quartz-made injector to reduce the production of silicon fluorides from the use of HF solvent. An actively cooled membrane desolvation component was attached after the APEX to suppress oxide formation and to stabilize the signals, and N₂ gas at a flow rate of a few ml min⁻¹ was added to improve the sensitivity. Such a setting typically provides an intensity of around 15 V on ⁴⁸ Ti⁺ at an uptake rate of about 50 μl min⁻¹ for a 600-ppb Ti solution under a medium mass-resolution mode.

Until the early 20th century, the question of whether light is a particle or a wave had divided scientists for centuries. Isaac Newton held the former stance and advocated for his “corpuscular” theory. But by the early 19th century, the wave theory was making a comeback, thanks in part to the work of a French civil engineer named Augustin-Jean Fresnel.

Born in 1,788 to an architect, the young Fresnel had a strict religious upbringing, since his parents were Jansenists — a radical sect of the Catholic Church that embraced predestination. Initially he was home-schooled, and did not show early academic promise; he could barely read by the time he was eight. Part of this may have been due to all the political upheaval in France at the time. Fresnel was just one year old when revolutionaries stormed the Bastille in 1,789, and five when the Reign of Terror began.

Eventually the family settled in a small village north of Caen, and when Fresnel was 12, he was enrolled in a formal school. That is where he discovered science and mathematics. He excelled at both, so much so that he decided to study engineering, first at the École Polytechnique in Paris, and then at the École Nacionale des Ponts et Chaussées.

With 147 fused benzene rings and 920 conjugated atoms, the nanoribbon shows optoelectronic properties that could compete with quantum dots.

When you turn on a lamp to brighten a room, you are experiencing light energy transmitted as photons, which are small, discrete quantum packets of energy. These photons must obey the sometimes strange laws of quantum mechanics, which, for instance, dictate that photons are indivisible, but at the same time, allow a photon to be in two places at once.

Similar to the photons that make up beams of light, indivisible quantum particles called phonons make up a beam of sound. These particles emerge from the collective motion of quadrillions of atoms, much as a “stadium wave” in a sports arena is due to the motion of thousands of individual fans. When you listen to a song, you’re hearing a stream of these very small quantum particles.

Scientists at the Niels Bohr Institute, in cooperation with the University of Münster and Ruhr-Universität Bochum, developed new technology capable of processing the enormous amounts of information quantum systems generate. They’ve successfully linked deterministic single-photon.

A photon is a particle of light. It is the basic unit of light and other electromagnetic radiation, and is responsible for the electromagnetic force, one of the four fundamental forces of nature. Photons have no mass, but they do have energy and momentum. They travel at the speed of light in a vacuum, and can have different wavelengths, which correspond to different colors of light. Photons can also have different energies, which correspond to different frequencies of light.

Graphene is a two-dimensional wonder material that has been suggested for a wide range of applications in energy, technology, construction, and more since it was first isolated from graphite in 2004.

This single layer of carbon atoms is tough yet flexible, light but with high resistance, with graphene calculated to be 200 times more resistant than steel and five times lighter than aluminum.

Graphene may sound perfect, but it very literally is not. Isolated samples of this 2D allotrope aren’t perfectly flat, with its surface rippled. Graphene can also feature structural defects that can, in some cases, be deleterious to its function and, in other instances, can be essential to its chosen application. That means that the controlled implementation of defects could enable fine-tuning of the desired properties of two-dimensional crystals of graphene.

Looking only at their subatomic particles, most materials can be placed into one of two categories.

Metals—like copper and iron—have free-flowing electrons that allow them to conduct electricity, while insulators —like glass and rubbe r— keep their electrons tightly bound and therefore do not conduct electricity.

Insulators can turn into metals when hit with an intense electric field, offering tantalizing possibilities for microelectronics and supercomputing, but the physics behind this phenomenon called resistive switching is not well understood.

For decades, scientists have been probing the potential of two-dimensional materials to transform our world. 2D materials are only a single layer of atoms thick. Within them, subatomic particles like electrons can only move in two dimensions. This simple restriction can trigger unusual electron behavior, imbuing the materials with “exotic” properties like bizarre forms of magnetism, superconductivity and other collective behaviors among electrons—all of which could be useful in computing, communication, energy and other fields.

But researchers have generally assumed that these exotic 2D properties exist only in single-layer sheets, or short stacks. The so-called “bulk” versions of these materials—with their more complex 3D atomic structures—should behave differently.

Or so they thought.

A team of scientists studied the single-system version of multipartite Bell nonlocality, and observed the highest degree of quantum contextuality in a single system. Their work was published in Physical Review Letters.

Physical Review Letters (PRL) is a peer-reviewed scientific journal published by the American Physical Society. It is one of the most prestigious and influential journals in physics, with a high impact factor and a reputation for publishing groundbreaking research in all areas of physics, from particle physics to condensed matter physics and beyond. PRL is known for its rigorous standards and short article format, with a maximum length of four pages, making it an important venue for rapid communication of new findings and ideas in the physics community.