Abstract

Magnetic materials are essential for energy generation and information devices, and they play an important role in advanced technologies and green energy economies. Currently, the most widely used magnets contain rare earth (RE) elements. An outstanding challenge of notable scientific interest is the discovery and synthesis of novel magnetic materials without RE elements that meet the performance and cost goals for advanced electromagnetic devices.

Here, we report our discovery and synthesis of an RE-free magnetic compound, Fe3CoB2, through an efficient feedback framework by integrating machine learning (ML), an adaptive genetic algorithm, first-principles calculations, and experimental synthesis. Magnetic measurements show that Fe3CoB2 exhibits a high magnetic anisotropy (K1 = 1.2 MJ/m3) and saturation magnetic polarization (Js = 1.39 T), which is suitable for RE-free permanent-magnet applications.

Our ML-guided approach presents a promising paradigm for efficient materials design and discovery and can also be applied to the search for other functional materials.

https://www.pnas.org/doi/10.1073/pnas.2204485119

The team assembled a device and put it to use on Shenzhen Bay seawater (an inlet north of Hong Kong and Macau). And, by nearly every reasonable performance measure, it worked well.

It maintained performance even after 3,200 hours of use, and electron microscopy of the membrane after use indicated that the pores remained unblocked at this point. The KOH used for the system wasn't completely pure, so it contained low levels of the ions found in seawater. But those levels didn't increase over time, confirming that the system kept the seawater out of the electrolysis chamber. Power-wise, the system used about as much as a standard electrolyzer, confirming that the water purification wasn't exacting any energetic cost.

The KOH solution also was self-balancing, with water diffusion into the device slowing if its internal solution became too dilute. If it gets too concentrated, the efficiency of electrolysis drops, so the elimination of water slows down.

The authors estimate their device would handle pressures down to about 75 meters of seawater. The temperature at those depths might be limiting, however, as the diffusion rate of water across the membrane was six times higher at 30° C than it is at 0° C.

Even with all that good news, there are options for improving performance. Various salts beyond KOH are suitable, and some may perform better. The researchers also found that incorporating KOH into a hydrogel around the electrodes boosted hydrogen production. Finally, it's possible that altering the material or structure of the electrodes used in the water splitting could boost things further.

Finally, the team suggested that this might be useful for things in addition to hydrogen production. Instead of seawater, they immersed one of the devices into a dilute lithium solution and found that 200 hours of operation increased the lithium concentrations by more than 40-fold due to water moving into the device. There are plenty of other contexts, like purifying contaminated water, where this sort of concentration ability could be useful.

Abstract

Electrochemical saline water electrolysis using renewable energy as input is a highly desirable and sustainable method for the mass production of green hydrogen; however, its practical viability is seriously challenged by insufficient durability because of the electrode side reactions and corrosion issues arising from the complex components of seawater. Although catalyst engineering using polyanion coatings to suppress corrosion by chloride ions or creating highly selective electrocatalysts has been extensively exploited with modest success, it is still far from satisfactory for practical applications. Indirect seawater splitting by using a pre-desalination process can avoid side-reaction and corrosion problems, but it requires additional energy input, making it economically less attractive. In addition, the independent bulky desalination system makes seawater electrolysis systems less flexible in terms of size.

Here we propose a direct seawater electrolysis method for hydrogen production that radically addresses the side-reaction and corrosion problems. A demonstration system was stably operated at a current density of 250 milliamperes per square centimetre for over 3,200 hours under practical application conditions without failure. This strategy realizes efficient, size-flexible and scalable direct seawater electrolysis in a way similar to freshwater splitting without a notable increase in operation cost, and has high potential for practical application. Importantly, this configuration and mechanism promises further applications in simultaneous water-based effluent treatment and resource recovery and hydrogen generation in one step.

https://www.nature.com/articles/s41586-022-05379-5

their's there’s there's NOT

Potential cancer breakthrough as scientists finally discover how tumours 'hijack' healthy cells to spread around the body

Scientists have discovered that cancer cells ‘hijack’ a process used by healthy cells to spread around the body, completely changing current ways of thinking about cancer.

Despite being one of the main causes of death in cancer patients, metastasis — when cancer spreads — has remained incredibly difficult to prevent.

This is largely because researchers have found it hard to identify key drivers of this process, which could be targeted by drugs.

Now, they have discovered a protein called NALCN may play a key role.

In experiments in mice, they found that blocking the activity of the NALCN protein triggered metastasis.

They also discovered that when they removed the protein from mice without cancer, this caused their healthy cells to leave their original tissue and travel around the body where they joined other organs.

This suggests that metastasis isn’t an abnormal process limited to cancer as previously thought, but is a normal process used by healthy cells that has been exploited by cancers to migrate to other parts of the body.

NALCN stands for sodium (Na+) leak channel, non-selective. Sodium leak channels are expressed predominately in the central nervous system but are also found throughout the rest of the body.

These channels sit across the membranes of cells and control the amount of salt that goes in and out of the cell.

However, it is not yet clear why these channels seem to be implicated so directly in cancer metastasis.

Lead researcher on the study and senior research associate at the Cancer Research UK Cambridge Institute, Dr Eric Rahrmann, said: ‘We are incredibly excited to have identified a single protein that regulates not only how cancer spreads through the body, independent of tumour growth, but also normal tissue cell shedding and repair.

‘We are developing a clearer picture on the processes that govern how cancer cells spread.

'We can now consider whether there are likely existing drugs which could be repurposed to prevent this mechanism from triggering cancer spreading in patients.’

The findings were published in the journal Nature Genetics.

Abstract

We identify the sodium leak channel non-selective protein (NALCN) as a key regulator of cancer metastasis and nonmalignant cell dissemination. Among 10,022 human cancers, NALCN loss-of-function mutations were enriched in gastric and colorectal cancers. Deletion of Nalcn from gastric, intestinal or pancreatic adenocarcinomas in mice did not alter tumor incidence, but markedly increased the number of circulating tumor cells (CTCs) and metastases. Treatment of these mice with gadolinium-a NALCN channel blocker-similarly increased CTCs and metastases. Deletion of Nalcn from mice that lacked oncogenic mutations and never developed cancer caused shedding of epithelial cells into the blood at levels equivalent to those seen in tumor-bearing animals. These cells trafficked to distant organs to form normal structures including lung epithelium, and kidney glomeruli and tubules. Thus, NALCN regulates cell shedding from solid tissues independent of cancer, divorcing this process from tumorigenesis and unmasking a potential new target for antimetastatic therapies.