Imagine you can open your fridge, open an app on your phone and immediately know which items will go bad soon. This is one of the applications that a new technology developed by engineers at the University of California San Diego would enable.

The technology combines a chip (芯片) integrated into product packaging and a software update on your phone. The phone becomes capable of identifying objects based on signals the chip sends out from specific frequencies, in this case Bluetooth or WiFi. In an industrial setting, a smartphone equipped with the software update could be used as a radio frequency identification (RFID) reader.

The work uses breakthroughs in backscatter (反向散射) communication, which uses signals already generated by your smartphone and re-directs them back in a format your phone can understand. Effectively, this technique uses less power than the latest technology to generate WiFi signals.

The custom chip, which is roughly the size of a grain of sand and costs only a few pennies to produce, needs so little power that it can be entirely powered by LTE signals, a technique for wireless broadband communication for mobile devices. The chip turns Bluetooth signals into WiFi signals, which can in turn be detected by a smartphone with that specific software update.

The technology’s broader promise is the development of devices that do not need batteries because they can harvest power from LTE signals instead. This in turn would lead to devices that are significantly less expensive that last longer, said Dinesh Bharadia, one of the paper’s senior authors.

“E-waste, especially batteries, is one of the biggest problems the planet is facing, after climate change,” Bharadia said.

For future research, the team will integrate this technology into other projects to demonstrate its capabilities, and they also hope to commercialize it, either through a startup or through an industry partner.

Now, an increasing number of cities are suspending recycling services, partly out of fear that workers might contact the coronavirus from one another while sorting through used water bottles, food containers and boxes. One solution: Let robots do the job.

Since the coronavirus took hold in the United States last month, AMP Robotics has seen a “significant” increase in orders for its robots that use artificial intelligence to sort through recycled material, and weed out trash. Some facilities that were looking at getting one or two robots are now saying, “We need quite a bit more.” The Colorado company’s chief executive, Matanya Horowitz said, “It’s all moving quite fast.”

Before the pandemic, automation had been gradually replacing human work in a range of jobs, from call centers to warehouses and grocery stores, as companies looked to cut labor costs and improve profit.

But labor and robotics experts say social-distancing directives, which are likely to continue in some form after the crisis become less strong, could cause more industries to accelerate their use of automation. And long-lasting worries about job losses or a broad unease about having machines control vital aspects of daily life could disappear as society sees the benefits of restructuring workplaces in ways that minimize close human contact.

Recycling is one industry that may be altered permanently by the pandemic. Some workers, who earn as little as $10 an hour, have been concerned about coming to work during the crisis and some cities have been competing to find enough protective gear (防护装备) for all of their employees. Federal health officials have assured them that the risks of transmission from household refuse is low. But workers in recycling facilities often work side by side sorting material, making social distancing difficult.

At AMP Robotics, executives like Mr. Horowitz say their robots will enable recycling facilities to space out their employees, who stand at conveyor belts weeding through the used plastic and paper.

New bio-plastics are being made in laboratories from straw, wood chips and food waste, with researchers aiming to replace oil as the source of the world’s plastic.

The new approaches include genetically modifying bacteria to eat wood and produce useful chemicals. But the bio-plastics are currently significantly more expensive to make than fossil fuel-based plastics.

Land and seas around the world, from high mountains to deep oceans, have become polluted with plastic, prompting major public concern. The world has produced 8bn tons of plastic since the 1950s and demand is still rising.

While some waste plastic is recycled, much of it is burnt to produce electricity, resulting in carbon emissions that drive climate change. In contrast to plastic made from oil, plastics made from plant-based materials only release the carbon the plants absorbed from the air as they grew. Bio-plastics will also give more options for products that biodegrade (生物降解) in the environment, although they can be made very long-lasting if required.

“Plastics are an incredible enhancement to our daily lives,” said Paul Mines, CEO of Biome Technologies in the UK, which has spent t5m in the last five years on bio-plastics research. “But we can’t go on using fossil fuel-based materials. About 6-7% of every barrel (桶) of oil is used to make plastics.”

“Using plant materials is feasible,” said professor Simon, at the University of York. “Replacing half of the nation’s plastic bottles could be done using just 3% of the sugar beet crop, 5% of wheat straw or 2.5% of food waste,” he said.

Currently, just a few thousand tons of bio-plastic are used in the UK each year, compared to millions of tons of conventional plastic. Mines said this could rise to about 20,000 tons in the next five years.

......