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Graphene typically costs $200,000 per ton. Now, scientists can make it from trash.
Graphene is insanely useful, but very difficult to produce — until now.
- Graphene is a lattice of carbon atoms arranged in a chicken-wire formation, a structure that makes it very useful for a wide range of applications.
- However, it's been very difficult and expensive to make.
- This new technique cuts down on the cost and difficulty by flash heating any carbon-based material, such as used coffee grounds or plastic waste.
Recent technology developed at Rice University is taking the idea that one man's trash is another man's treasure to its extreme. Banana peels, coffee grounds, single-use plastic containers, coal — all of these and more are being turned into one of the most valuable materials around: graphene. Chemist James Tour and his team have developed a rapid process that can transform bulk-quantities of junk into flakes of graphene.
"This is a big deal," said Tour in a Rice University press release. "The world throws out 30 percent to 40 percent of all food, because it goes bad, and plastic waste is of worldwide concern. We've already proven that any solid carbon-based matter, including mixed plastic waste and rubber tires, can be turned into graphene."
What is graphene?
A rendering of graphene.
Graphene's value is mainly due to its incredible strength and the wide variety of industrial applications it possesses. This material consists of a single layer of carbon atoms connected to one another by six chemical bonds, creating a lattice that resembles chicken wire.
Not only is graphene extremely useful in scientific experiments due to its high reactivity and strength, it can also be added to all sorts of other materials to improve their strength or to make them more lightweight, such as concrete or metals. It is the most conductive material, making it invaluable for use as a heat sink in, for instance, LEDs or smartphones. It could also be used in battery technology, in paints, in sensors, and many more — there are quite literally too many applications for this material to cover in this article alone.
What is 'flash graphene'?
Despite its high utility, graphene isn't a part of our everyday lives yet. Part of the reason why is because of its prohibitive cost. Graphene is difficult to produce in bulk, with "the present commercial price of graphene being $67,000 to $200,000 per ton," said Tour. Common techniques include exfoliation, in which sheets of graphene are stripped away from graphite, or chemical vapor deposition, in which methane (CH4) is vaporized in the presence of a copper substrate that grabs the methane's carbon atoms, arranging them as graphene.
The new technique, called flash Joule heating, is far simpler, cheaper, and doesn't rely on any hazardous solvents or chemical additives. Simply put, a carbon-based material is exposed to a 2,760°C (5,000°F) heat for just 10 milliseconds. This breaks every chemical bond in the input material. All atoms aside from carbon turn into gas, which escape in this proof-of-concept device but could be captured in industrial applications. The carbon, however, reassembles itself as flakes of graphene.
What's more, this technique produces so-called turbostatic graphene. Other processes produce what's known as A-B stacked graphene, in which half of the atoms in one sheet of graphene lie over the atoms of another sheet of graphene. This results in a tighter bond between the two sheets, making them harder to separate. Turbostatic graphene has no such order between sheets, so they're easier to remove from one another.
The most obvious use case for what the researchers have termed "flash graphene" is to use these graphene flakes as a component in concrete. "By strengthening concrete with graphene," said Tour, "we could use less concrete for building, and it would cost less to manufacture and less to transport. Essentially, we're trapping greenhouse gases like carbon dioxide and methane that waste food would have emitted in landfills. We are converting those carbons into graphene and adding that graphene to concrete, thereby lowering the amount of carbon dioxide generated in concrete manufacture. It's a win-win environmental scenario using graphene."
Concrete is a major application for this material, one that would both be economically and environmentally sound, but many others exist too. As this method and others for producing graphene in bulk mature, we can hope to see a future with increasingly stronger, more lightweight, more advanced, and less environmentally destructive materials and technologies.
What is human dignity? Here's a primer, told through 200 years of great essays, lectures, and novels.
- Human dignity means that each of our lives have an unimpeachable value simply because we are human, and therefore we are deserving of a baseline level of respect.
- That baseline requires more than the absence of violence, discrimination, and authoritarianism. It means giving individuals the freedom to pursue their own happiness and purpose.
- We look at incredible writings from the last 200 years that illustrate the push for human dignity in regards to slavery, equality, communism, free speech and education.
The inherent worth of all human beings<p>Human dignity is the inherent worth of each individual human being. Recognizing human dignity means respecting human beings' special value—value that sets us apart from other animals; value that is intrinsic and cannot be lost.</p> <p>Liberalism—the broad political philosophy that organizes society around liberty, justice, and equality—is rooted in the idea of human dignity. Liberalism assumes each of our lives, plans, and preferences have some unimpeachable value, not because of any objective evaluation or contribution to a greater good, but simply because they belong to a human being. We are human, and therefore deserving of a baseline level of respect. </p> <p>Because so many of us take human dignity for granted—just a fact of our humanness—it's usually only when someone's dignity is ignored or violated that we feel compelled to talk about it. </p> <p>But human dignity means more than the absence of violence, discrimination, and authoritarianism. It means giving individuals the freedom to pursue their own happiness and purpose—a freedom that can be hampered by restrictive social institutions or the tyranny of the majority. The liberal ideal of the good society is not just peaceful but also pluralistic: It is a society in which we respect others' right to think and live differently than we do.</p>
From the 19th century to today<p>With <a href="https://books.google.com/ngrams/graph?year_start=1800&year_end=2019&content=human+dignity&corpus=26&smoothing=3&direct_url=t1%3B%2Chuman%20dignity%3B%2Cc0" target="_blank" rel="noopener noreferrer">Google Books Ngram Viewer</a>, we can chart mentions of human dignity from 1800-2019.</p><img type="lazy-image" data-runner-src="https://assets.rebelmouse.io/eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJpbWFnZSI6Imh0dHBzOi8vYXNzZXRzLnJibC5tcy8yNDg0ODU0My9vcmlnaW4ucG5nIiwiZXhwaXJlc19hdCI6MTY1MTUwMzE4MX0.bu0D_0uQuyNLyJjfRESNhu7twkJ5nxu8pQtfa1w3hZs/img.png?width=980" id="7ef38" class="rm-shortcode" data-rm-shortcode-id="9974c7bef3812fcb36858f325889e3c6" data-rm-shortcode-name="rebelmouse-image" />
American novelist, writer, playwright, poet, essayist and civil rights activist James Baldwin at his home in Saint-Paul-de-Vence, southern France, on November 6, 1979.
Credit: Ralph Gatti/AFP via Getty Images
The future of dignity<p>Around the world, people are still working toward the full and equal recognition of human dignity. Every year, new speeches and writings help us understand what dignity is—not only what it looks like when dignity is violated but also what it looks like when dignity is honored. In his posthumous essay, Congressman Lewis wrote, "When historians pick up their pens to write the story of the 21st century, let them say that it was your generation who laid down the heavy burdens of hate at last and that peace finally triumphed over violence, aggression and war."</p> <p>The more we talk about human dignity, the better we understand it. And the sooner we can make progress toward a shared vision of peace, freedom, and mutual respect for all. </p>
Scientists find that bursts of gamma rays may exceed the speed of light and cause time-reversibility.
- Astrophysicists propose that gamma-ray bursts may exceed the speed of light.
- The superluminal jets may also be responsible for time-reversibility.
- The finding doesn't go against Einstein's theory because this effect happens in the jet medium not a vacuum.
Jet bursting out of a blazar. Black-hole-powered galaxies called blazars are the most common sources detected by NASA's Fermi Gamma-ray Space Telescope.
Cosmic death beams: Understanding gamma ray bursts<div class="rm-shortcode" data-media_id="cu2knVEk" data-player_id="FvQKszTI" data-rm-shortcode-id="c6cfd20fdf31c82cb206ade8ce21ba3f"> <div id="botr_cu2knVEk_FvQKszTI_div" class="jwplayer-media" data-jwplayer-video-src="https://content.jwplatform.com/players/cu2knVEk-FvQKszTI.js"> <img src="https://cdn.jwplayer.com/thumbs/cu2knVEk-1920.jpg" class="jwplayer-media-preview" /> </div> <script src="https://content.jwplatform.com/players/cu2knVEk-FvQKszTI.js"></script> </div>
A new study finds that some people just want privacy.
- Despite its reputation as a tool for criminals, only a small percentage of Tor users were actually going to the dark web.
- The rate was higher in free countries and lower in countries with censored internet access.
- The findings are controversial, and may be limited by their methodology to be general assumptions.
What do half of those words mean?<p> For those who don't spend all of their time on the internet, a few of these terms might be new to you. We'll go over them first before we continue. If you do know all of these terms, you can skip ahead to the next section.<br> <br> <em>Surface Web:</em> The regular internet that you can find with a search engine. You're on it right now; unless these articles are shared in places we don't know about. <br> <br> <em>Deep Web</em>: The part of the internet not indexed by search engines. This includes things like your email inbox; you can't get there from Google or Bing, but instead have to enter a password to find it from another page. You've probably visited the deep web today, too. </p><p><em>Dark Web</em>: A subsection of the deep web that requires special software to access. While not everything there is bad, there are social media sites, email services, hidden forums, and even puzzle games down there; this is also where you would find the places for illegal markets and other, extremely nefarious, things.</p><p> <em>Tor:</em> A kind of software that allows users to browse the internet in near-total anonymity. It does this by encrypting connection data and scrambling the route a computer takes to connect to a site, thus making it difficult, but not impossible, to find who is using a particular website. The potential value of this to criminals should be evident to you. <br> <br> While it often gets bad press for how it can be used for illicit purposes, it should be said it was created and used by the United States government for often banal purposes. The leaders of the Tor Project often remind the public that "normal people" use Tor for everyday internet activities as well.</p><p> As a personal example, I once used it to get around the <a href="https://www.wired.com/1997/06/china-3/" target="_blank">Great Firewall of China</a> when I wanted to get to the regular, uncensored internet.</p>
Back to the study<p> The study observed the final destination of a random selection of Tor users to determine if they went to surface websites or more hidden areas of the internet after connecting to the Tor network. This was done by monitoring the data from entry points in the Tor network, which would allow an observer to where someone was going, but not who.</p><p> Those going to surface websites were assumed just to be using Tor for anonymity and security, while those going into the dark web were presumed more likely to be using it for illegal reasons. <br> </p><p> Despite the popular conception of Tor as a tool for criminals looking to cover their tracks, only 6.7 percent of these users went to sites defined as the dark web, which were themselves not necessarily devoted to illegal <a href="https://www.sciencealert.com/only-a-small-fraction-of-the-dark-web-is-being-used-for-hidden-activity-study-finds" target="_blank" rel="noopener noreferrer">activity</a>. </p><p> The results were further broken down by country, which revealed another layer of information. The authors noted that in countries deemed "not free" by Freedom House, the rate of possible malicious use goes down to 4.8 percent. In countries considered free, the percentage nearly doubles to 7.8 percent.</p>
What does this mean for the internet?<iframe width="730" height="430" src="https://www.youtube.com/embed/MBh7K5ooF2s" frameborder="0" allow="accelerometer; autoplay; clipboard-write; encrypted-media; gyroscope; picture-in-picture" allowfullscreen></iframe><p> The dark web might be a little lighter than previously suggested. While it is true that there is some horrible stuff down there, this study suggests the people getting to it using the Tor network are mostly using it for legal, and perhaps even banal, purposes. This interpretation is additionally supported by the difference in usage across countries judged free and not free. In those countries with censorship, where a variety of tools must be used to get to sites like Facebook or Wikipedia, the percentage of users going towards locations on the dark web was smaller.</p><p>The authors conclude:</p><p style="margin-left: 20px;"> "The Tor anonymity network can be used for both licit and illicit purposes. Our results provide a clear, if probabilistic, estimation of the extent to which users of Tor engage in either form of activity. Generally, users of Tor in politically 'free' countries are significantly more likely to be using the network in likely illicit ways."</p><p> Additionally, they mention that the Tor network's infrastructure is predominately in free countries, which then see higher rates of its use to reach places that could advance illegal activities. This find may be of interest to policymakers looking to balance the promotion of autonomy and the freedom of information with the goal of preventing crime.</p>
What’s the catch?<iframe width="730" height="430" src="https://www.youtube.com/embed/2UNUMgM9Gwo" frameborder="0" allow="accelerometer; autoplay; clipboard-write; encrypted-media; gyroscope; picture-in-picture" allowfullscreen></iframe><p> It has been suggested that the internet is the first thing humanity ever created that we don't fully understand. If that is true, it should surprise no one that there are objections to the methods used to study it. <br> <br> The executive director of the Tor Project, Isabela Bagueros, explained their objection to the study's methodology and assumptions to <a href="https://arstechnica.com/gadgets/2020/11/does-tor-provide-more-benefit-or-harm-new-paper-says-it-depends/" target="_blank" rel="noopener noreferrer">Ars Technica</a>:</p><p style="margin-left: 20px;"> <em>"The authors of this research paper have chosen to categorize all .onion sites and all traffic to these sites as "illicit" and all traffic on the "Clear Web" as 'licit.'</em></p><p style="margin-left: 20px;"><em>This assumption is flawed. Many popular websites, tools, and services use onion services to offer privacy and censorship-circumvention benefits to their users. For example, Facebook offers an onion service. Global news organizations, including The New York Times, BBC, Deutsche Welle, Mada Masr, and Buzzfeed, offer onion services.</em></p><p style="margin-left: 20px;"><em>Whistleblowing platforms, filesharing tools, messaging apps, VPNs, browsers, email services, and free software projects also use onion services to offer privacy protections to their users, including Riseup, OnionShare, SecureDrop, GlobaLeaks, ProtonMail, Debian, Mullvad VPN, Ricochet Refresh, Briar, and Qubes OS…...</em></p><p style="margin-left: 20px;"><em>Writing off traffic to these widely-used sites and services as "illicit" is a generalization that demonizes people and organizations who choose technology that allows them to protect their privacy and circumvent censorship. In a world of increasing surveillance capitalism and internet censorship, online privacy is necessary for many of us to exercise our human rights to freely access information, share our ideas, and communicate with one another. Incorrectly identifying all onion service traffic as "illicit" harms the fight to protect encryption and benefits the powers that be that are trying to weaken or entirely outlaw strong privacy technology."</em><br> </p><p>The critique here is justified; there are legitimate websites hidden behind layers of security which were deemed "illicit" by this study's methods. Many people are just trying to protect their anonymity when using them. However, the study's authors based their assumption on previous studies that demonstrate that these hidden sites are used for illegal activities at a higher rate than other parts of the <a href="https://www.cigionline.org/sites/default/files/no20_0.pdf" target="_blank" rel="noopener noreferrer">internet</a>.</p><p>Until a more rigorous and ethically ambiguous method of determining what people using the network are doing on these dark websites is utilized, the findings of studies like this will be general and based on broad assumptions. </p><p>Despite all of this, we can take a few things from this study: most people using Tor to explore the internet aren't using it for evil, those using it in places with limited freedom of information are even less likely to use it for such purposes, and external factors can have significant impacts on how people use a tool such as the internet. <br></p>
Researchers dramatically improve the accuracy of a number that connects fundamental forces.
- A team of physicists carried out experiments to determine the precise value of the fine-structure constant.
- This pure number describes the strength of the electromagnetic forces between elementary particles.
- The scientists improved the accuracy of this measurement by 2.5 times.
The process for measuring the fine-structure constant involved a beam of light from a laser that caused an atom to recoil. The red and blue colors indicate the light wave's peaks and troughs, respectively.
Scientists at Washington University are patenting a new electrolyzer designed for frigid Martian water.