Light-emitting diodes (LEDs) have revolutionized modern lighting and display technology, offering energy efficiency, durability, and versatility. Among the myriad colors they can emit, the blue LED holds particular significance due to its pivotal role in advancing LED technology. This essay explores the fascinating history and development of the blue LED, tracing its journey from theoretical conception to practical realization and its transformative impact on various industries.
Early Discoveries The journey towards the blue LED began with fundamental research into semiconductor physics and materials science. In the 1950s and 1960s, scientists were exploring the properties of different materials and experimenting with semiconductor junctions to understand their behavior. It was in this era that researchers first observed electroluminescence, the phenomenon of a material emitting light when subjected to an electric current. In 1972, Herbert Paul Maruska and Jacques Pankove at RCA Laboratories achieved the first demonstration of a blue-emitting LED using zinc-doped gallium nitride (GaN:Zn). However, the efficiency and practicality of these early blue LEDs were limited, and they remained a scientific curiosity rather than a commercially viable technology. Breakthroughs in Materials Science The quest for a commercially feasible blue LED gained momentum in the 1980s and 1990s as researchers delved deeper into materials science and semiconductor engineering. Shuji Nakamura, a Japanese engineer working at Nichia Corporation, made significant breakthroughs in this field. Nakamura focused on developing gallium nitride (GaN) based semiconductors, which had the potential to emit blue light when appropriately doped and fabricated. In 1993, Nakamura succeeded in creating the first high-brightness blue LED using gallium nitride. He achieved this breakthrough by inventing a new method for growing high-quality GaN crystals, known as metalorganic chemical vapor deposition (MOCVD). This innovation significantly improved the efficiency and reliability of blue LEDs, paving the way for their commercialization. Commercialization and Applications The commercialization of blue LEDs marked a turning point in the lighting industry. Blue LEDs, when combined with red and green LEDs, enabled the creation of white light, opening up new possibilities for energy-efficient lighting solutions. The development of blue LED backlighting also revolutionized the display industry, leading to thinner, brighter, and more vibrant displays in devices such as smartphones, televisions, and laptops. Moreover, blue LEDs found applications beyond lighting and displays. They became essential components in optical storage devices like Blu-ray discs, which utilize blue laser diodes for high-density data storage. Additionally, blue LEDs have been instrumental in the advancement of medical and scientific instrumentation, including fluorescence microscopy and photodynamic therapy. Recognition and Impact In recognition of his pioneering work on blue LEDs, Shuji Nakamura was awarded the Nobel Prize in Physics in 2014, alongside Isamu Akasaki and Hiroshi Amano, who also made significant contributions to LED technology. Their groundbreaking research not only revolutionized lighting and display technology but also contributed to energy conservation and sustainability efforts worldwide. The history and development of the blue LED exemplify the power of scientific inquiry, technological innovation, and interdisciplinary collaboration. From humble beginnings as a scientific curiosity to becoming an indispensable component of modern technology, the blue LED has illuminated our world in more ways than one. As we continue to push the boundaries of materials science and engineering, the legacy of the blue LED serves as a beacon of inspiration for future innovations yet to come.
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Scientists have hailed a potentially ‘revolutionary’ breakthrough in the early diagnosis of Alzheimer’s, after a team of Swedish researchers found that a commercially available blood test can detect biological markers of the disease about ten to 15 years before symptoms develop.
In a study of 768 people in their fifties, sixties, and seventies over an eight-year period conducted by the University of Gothenburg, it was found that the test – which detects the presence of tau proteins in blood – was 97% accurate in assessing if a subject was liable to develop the disease. The results of the study, published in the JAMA Neurology journal on Monday, have been hailed as a breakthrough in early screening tests for the disease well in advance of the onset of symptoms. Alzheimer’s, which causes the brain to shrink and its cells to eventually die, is the most common form of dementia, and is characterized by a decline in cognitive function, as well as behavior and social skills. The research “adds to a growing body of evidence that this particular test has huge potential to revolutionize diagnosis for people with suspected Alzheimer’s,” Sheona Scales, the director of research at Alzheimer’s Research UK, said, according to The Times on Monday. She added that the testing is “superior to a range of other tests currently under development,” and preferable to more invasive methods currently used by medical practitioners, such as lumbar punctures. David Curtis of the UCL Genetics Institute said that the findings of the Swedish team of scientists “could potentially have huge implications.” “Everybody over 50 could be routinely screened every few years, in much the same way as they are now screened for high cholesterol,” he added. “It is possible that currently available treatments for Alzheimer’s disease would work better in those diagnosed early this way.” The developer of the blood test, Californian company ALZpath, has said that it hopes to make the test widely available for clinical use in the first quarter of this year. About 1 in 9 people (10.7%) aged 65 or over has the disease, according to data from the Alzheimer’s Association. This is expected to rise substantially in the next 25 years, the group says on its website, “barring the development of medical breakthroughs to prevent or cure Alzheimer’s disease.” In the past week, stories in the media have been warning about the latest Covid-19 variant, the latest in a long list. It doesn’t seem like people are listening anymore.
In the minds of much of the public, the pandemic is long over and is firmly a thing of the past. The last thing most people want is another trip down the rabbit hole of restrictions, lockdowns, masks and vaccinations, with the past few years having seriously undermined the credibility of governments and public trust in them to do the right thing. And Western governments no longer have the political will or interest to dare make unpopular decisions, even if some are sounding the alarm. The pandemic in many respects was a turning point in government-public relations in Western countries, precisely because it was the first outbreak of such scale to occur in the age of mass social-media culture, where people, more connected than ever before, have the unrestricted capability to voice their own opinions, to hear the opinions of others, and with these to enact dissent against governments and their policies. The social-media era has already provided many significant challenges to state structures as it is, with Western governments scrambling to reassert a “narrative control” over their populations that they've since lost. Social-media freedom has played a critical role in – if not outright caused – outcomes which have shocked elites, be it the election of Donald Trump in the US, or Brexit in Britain. Subsequently, Western ruling classes have increased censorship and narrative policing on social media platforms through denouncing viewpoints they don’t like as “misinformation” or even as malicious propaganda by foreign actors like China or Russia. The Covid-19 pandemic thus saw one of the most comprehensive censorship campaigns Western governments had ever undertaken (at least before that of the Ukraine conflict), especially when it came to those who sought to question or challenge the need for vaccines. Governments have tried to aggressively reassert narrative control, stomping out dissent against their views, broadcast by establishment media. It would be foolish to deny that vaccines were important in combating the Covid-19 pandemic, even critical to saving lives, especially among the elderly and the vulnerable, but the manner in which this issue was conducted by governments has produced wholesale distrust in authority at large. That is not because vaccines are 'bad' but because people saw the profits being raked in by their Big Pharma producers, saw how aggressively governments were pushing for their implementation, and were skeptical as to whether the whole thing really served the “public interest.” In other words, the method (propaganda and censorship) defeated the objective (introducing vaccines to save lives). Big Pharma, of course, refers to a group of multinational drug- and medicine-producing companies which wield enough political influence and connections to be able to steer the public narrative towards endorsing their own products and which therefore exerts a monopoly over the perceived solutions to a health crisis or problem. These companies profited wholesale over the pandemic and to some extent influenced government policies over the issue. But more specifically, the narrative was steered to argue that the vaccines from Pfizer and Moderna were the only ones you should use, with Chinese and Russian competitors often receiving targeted negative coverage. Therefore, as it goes, public criticism of pandemic-related policies has grown because it is now more widely believed that these companies, armed with the media, exert “scaremongering” to fulfil their commercial goals. Combined with the influence of social media, this has created large-scale distrust, despite all evidence of how harmful and deadly the early forms of Covid were, especially for the sick and the elderly, and of the significant numbers of Covid-related deaths being reported to this day. As a result, continuing to sound alarm bells about new variants and the spread of the disease does more harm than good, because it reinforces perceptions that the media are attempting to scare populations with something that is not a real threat. The pandemic has had a politically exhausting effect that also came with a choppy transition back to 'real' life. The public is not interested in making sacrifices again in the name of a disease that is already perceived to have 'gone away,' especially when it is believed there is an agenda behind doing so – not just Big Pharma’s but also one of power centralization, censorship and narrative-control by governments. The pandemic and the Ukraine conflict together have marked part of a shift whereby Western states have sought to reassert power lost during the social-media era, but have only achieved the opposite effect. Hungarian-born Katalin Kariko and Drew Weissman of the US have won the 2023 Nobel Prize in Physiology or Medicine for their research that led directly to the first mRNA vaccines to fight COVID-19, made by Pfizer and Moderna, according to the awarding body.
“The laureates contributed to the unprecedented rate of vaccine development during one of the greatest threats to human health in modern times,” the jury said in Sweden’s capital Stockholm on Monday. Katalin Kariko is a professor at Sagan’s University in Hungary and an adjunct professor at the University of Pennsylvania. Drew Weissman conducted his prizewinning research together with Kariko at the University of Pennsylvania. The pair will receive their prize, consisting of a diploma, a gold medal and a $1m cheque, from King Carl XVI Gustaf at a formal ceremony in Stockholm on December 10, the anniversary of the 1896 death of scientist Alfred Nobel who created the prizes in his last will and testament. The frontrunners for this year’s award in medicine included Kevan Shokat, an American biologist who figured out how to block the KRAS cancer gene behind a third of cancers, including challenging-to-treat lung, colon,\ and pancreatic tumours. Two American biologists, Stanislas Leibler and Michael Elowitz, were also in the run for their work on synthetic gene circuits which established the field of synthetic biology. It enables scientists to redesign organisms by engineering them to have new abilities. The Nobel Prize in physiology or medicine was won last year by Swedish scientist Svante Paabo for discoveries in human evolution that unlocked secrets of Neanderthal DNA which provided key insights into our immune system, including our vulnerability to severe COVID-19. The physics prize will be announced on Tuesday, chemistry on Wednesday and literature on Thursday. The Nobel Peace Prize will be announced on Friday and the economics award on October 9. The 20th century witnessed an unprecedented acceleration in scientific and technological advancements, reshaping the world in profound ways. At the heart of this transformative period stands J. Robert Oppenheimer, a brilliant physicist whose contributions to the development of the atomic bomb and his broader impact on science and society remain both remarkable and controversial. Oppenheimer's life and work provide a fascinating glimpse into the complexities of human ingenuity, ethical dilemmas, and the responsibility that accompanies scientific breakthroughs.
J. Robert Oppenheimer was born on April 22, 1904, in New York City. From an early age, his intellectual curiosity and exceptional aptitude for physics became evident. He pursued his education at prestigious institutions, including Harvard University and the University of Cambridge, where he studied under renowned physicists such as Max Born and Niels Bohr. Oppenheimer's early research focused on quantum mechanics and theoretical physics, showcasing his remarkable ability to navigate complex scientific ideas. However, Oppenheimer's most enduring legacy is intrinsically tied to his role as the scientific director of the Manhattan Project during World War II. As the world grappled with the horrors of war and the Axis powers' potential for harnessing nuclear energy, the United States initiated an ambitious effort to develop an atomic bomb. Oppenheimer's leadership and contributions were pivotal in bringing together a diverse group of scientists and engineers to work towards this goal. Under his guidance, the Los Alamos Laboratory became a crucible of innovation, where groundbreaking research in nuclear physics and engineering was conducted. The successful culmination of the Manhattan Project led to the creation of the world's first atomic bomb, which was used in the bombings of Hiroshima and Nagasaki in 1945. The devastating power of these bombs ushered in the atomic age, with profound implications for global politics, security, and ethics. Oppenheimer's involvement in the development of these weapons posed a moral conundrum, and he famously quoted the Bhagavad Gita upon witnessing the first successful test: "Now I am become Death, the destroyer of worlds." This expression of remorse and awareness of the destructive potential of his work underscores the complexity of scientific advancements and their ethical ramifications. Following World War II, Oppenheimer's life took a different turn as he became an advocate for arms control and international cooperation. He recognized the urgency of preventing the proliferation of nuclear weapons and worked to ensure that the destructive power he had helped unleash would not engulf the world in further conflict. His efforts culminated in the Atoms for Peace program, which aimed to promote the peaceful uses of nuclear technology while curbing its militarization. Despite his contributions to science and his efforts towards disarmament, Oppenheimer's political beliefs and associations eventually came under scrutiny during the era of McCarthyism and the Red Scare. Accusations of communist sympathies led to a controversial security clearance hearing in 1954, where his loyalty to the United States was questioned. The revocation of his security clearance marked a tragic chapter in his life, as he faced professional isolation and personal distress. J. Robert Oppenheimer's life and legacy reflect the intricate interplay between scientific progress, ethical considerations, and the complex forces that shape historical narratives. His contributions to physics, his role in the development of the atomic bomb, and his subsequent advocacy for arms control underscore the intricate relationship between science and society. His story serves as a reminder that even the most brilliant minds are not immune to the ethical dilemmas and moral responsibilities that arise from their work. In conclusion, J. Robert Oppenheimer's life story embodies the dual nature of scientific innovation—its potential to reshape the world for both better and worse. His contributions to physics and his central role in the Manhattan Project forever link him to the atomic age, a period of history defined by both scientific achievement and profound ethical dilemmas. As we reflect on his life and work, we are reminded of the necessity for careful consideration of the consequences of scientific advancements and the importance of fostering a dialogue that balances human ingenuity with ethical imperatives. Researchers from the National University of Singapore (NUS) stumbled upon a discovery that could forever revolutionize how we acquire hydrogen from water, according to a press release from the institution published on Thursday.
Light as a trigger The team was led by Associate Professor Xue Jun Min, Dr Wang Xiaopeng and Dr Vincent Lee Wee Siang from the Department of Materials Science and Engineering under the NUS College of Design and Engineering (NUS CDE). The discovery they made was that light could trigger a new mechanism in a catalytic material used in water electrolysis. “We discovered that the redox center for electro-catalytic reaction is switched between metal and oxygen, triggered by light,” said Jun Min. “This largely improves the water electrolysis efficiency.” It all began with an accidental power trip of the ceiling lights in Jun Min’s laboratory almost three years ago. Back then, the ceiling lights in Jun Min’s research lab were normally turned on for 24 hours. When the lights went off due to a power failure, there was an opportunity to observe something that scientists had never witnessed before. When the researchers returned the next day, they found that the darkness had influenced the performance of a nickel oxyhydroxide-based material in the water electrolysis experiment. It had fallen drastically. “This drop in performance, nobody has ever noticed it before, because no one has ever done the experiment in the dark,” said Jun Min. “Also, the literature says that such a material shouldn’t be sensitive to light; light should not have any effect on its properties.” Jun Min and his team knew they had stumbled on something significant, and they embarked on numerous repeated experiments to test out their new theories. They eventually had enough data to publish a paper. Now, the team is working on new ways to improve industrial processes to generate hydrogen such as making the cells containing water to be transparent, so as to introduce light into the water splitting process. Since 1945, more than 2,000 nuclear test explosions have been conducted by at least eight nations. August 29 marks the International Day against Nuclear Tests. The day, declared by the United Nations in 2009, aims to raise awareness of the effects of nuclear weapons testing and achieve a nuclear-weapons-free world. On July 16, 1945, during World War II, the United States detonated the world’s first nuclear weapon, codenamed Trinity, over the New Mexico desert. Less than a month later, the US dropped two atomic bombs on the Japanese cities of Hiroshima and Nagasaki, killing more than 100,000 people instantly. Thousands more died from their injuries, radiation sickness and cancer in the years that followed, bringing the toll closer to 200,000, according to the US Department of Energy’s history of the Manhattan Project. Nuclear warheads per country
Nine countries possessed roughly 12,700 warheads as of early 2022, according to the Federation of American Scientists. Approximately 90 percent are owned by Russia (5,977 warheads) and the US (5,428 warheads). At its peak in 1986, the two rivals had nearly 65,000 nuclear warheads between them, making the nuclear arms race one of the most threatening events of the Cold War. While Russia and the US have dismantled thousands of warheads, several countries are thought to be increasing their stockpiles, notably China. The only country to voluntarily relinquish nuclear weapons is South Africa. In 1989, the government halted its nuclear weapons programme and in 1990 began dismantling its six nuclear weapons. In 1991, South Africa joined the Treaty on the Non-Proliferation of Nuclear Weapons (NPT) as a non-nuclear country. The Dutch government announced it will allocate € 60 million ($ 65.4 million), to support the formation of an ecosystem around cellular agriculture. It represents the largest public funding into the cellular agriculture field ever, globally. The funding is awarded under conditions by the National Growth Fund, which aims to create structural economic growth by investing in the public domain to support innovative economic sectors.
We are proud to be part of the consortium that submitted the cellular agriculture growth plan, Cellular Agriculture Netherlands. Together with this group of Dutch entrepreneurs, scientists, academics and food pioneers we are developing a more sustainable food system that makes sure people can eat the food they love, without harming people, the planet or animals. This financial impulse represents a first step towards funding a larger growth plan proposing to invest € 252 – € 382 mln in cellular agriculture, specifically stimulating cellular agriculture education, academic research, publicly accessible scale-up facilities, societal integration (including farmers and consumers) and innovation. The broader growth plan is projected to generate an incremental €10 – €14 billion in Dutch GDP growth per year by 2050, with significant global climate, environmental and health benefits. For example avoiding ~12 Mton CO2-eq. emissions and 100-130 kton ammonia per year in 2050. “We are very excited for the visionary leadership the Dutch government is demonstrating today again,” said Ira van Eelen, on behalf of the Dutch Cellular Agriculture Foundation. “The Netherlands is the ideal place for cellular agriculture to flourish. It has a rich history in laying the global foundations of cellular agriculture. It is a global powerhouse in alternative protein and food innovation. It has a global frontrunner position in biotechnology and agriculture. It is the 2nd biggest exporter of traditional agricultural products in the world. And let’s not forget, it was the first country to publicly fund cultivated meat research and present the first proof of concept hamburger to the world. This is a great way to grow sustainably whilst our growth is currently under pressure.” The Netherlands has a strong history of innovating food production. This public investment in cellular agriculture is a demonstration of the Dutch government’s commitment to building an agricultural ecosystem that is healthy and sustainable. In combination with reforms to traditional farming, cellular agriculture can be an additional tool to satisfy the world’s growing appetite for protein. While individual cellular agriculture companies have been successful in attracting private funding, the Growth Fund financing is explicitly aiming to support the public part of the ecosystem. The expectation is that this impulse will attract more companies, more funding, and more collaboration across the cellular agriculture field in and with The Netherlands over the next few years. This announcement is not changing the process individual companies have to follow to obtain regulatory approval to sell their products, which is the European Novel Foods procedure. “Cultured meat is a fast-growing industry and it’s important to invest and support education and research across all areas from universities to research labs as well as informing the wider population about this dynamic industry. This is an exciting next step in the development of the cellular agriculture ecosystem, supporting this innovative new industry like so many other emerging industries before it, and one that will be beneficial to us all,” concludes Daan Luining CTO & co-founder of Meatable. The political fiction that humans cause most or all climate change and the claim that the science behind this notion is ‘settled’, has been dealt a savage blow by the publication of a ‘World Climate Declaration (WCD)’ signed by over 1,100 scientists and professionals. There is no climate emergency, say the authors, who are drawn from across the world and led by the Norwegian physics Nobel Prize laureate Professor Ivar Giaever. Climate science is said to have degenerated into a discussion based on beliefs, not on sound self-critical science. The scale of the opposition to modern day ‘settled’ climate science is remarkable, given how difficult it is in academia to raise grants for any climate research that departs from the political orthodoxy. (A full list of the signatories is available here.) Another lead author of the declaration, Professor Richard Lindzen, has called the current climate narrative “absurd”, but acknowledged that trillions of dollars and the relentless propaganda from grant-dependent academics and agenda-driven journalists currently says it is not absurd.
Renewables are projected to increase from its current 12% of the global energy supply to 90% in 2050. Yet the widespread use of renewables is challenged by the intermittency of solar and wind, and we’re not yet at a place where we can store enough energy to avoid these problems. As renewable energy supply increases around the world, so to is the demand for grid-scale energy storage. It has been projected that the combined global stationary and transportation annual energy storage market will increase from today’s baseline of around 600 GWh by a factor of four by 2030 to more than 2,500 GWh. Today, global energy storage capacity is dominated by gravity-based pumped hydro (90%), followed by lithium, lead and zinc batteries (5%), with the remaining capacity alloted to thermal and flow batteries, compressed air, flywheels, and other gravity-based mechanical systems.
Gravity energy storage Two ASN articles in 2019 about some exciting new developments in storing renewable energy as gravitational potential energy by lifting and lowering heavy objects (Gigawatt Electricity Storage Using Water and Rocks and Climate Change Will Require Heavy Lifting). At the time, a Swiss private company founded in 2017 that caught my attention was Energy Vault. In a demonstration project built and showcased in Switzerland, they showed the first use of cranes to lift and lower heavy composite blocks into massive architectures to respectively store and release significant amounts of renewable electricity. Importantly, the composite blocks enable the use of alternative materials to replace environmentally-unfriendly substances like concrete, which accounts for 7-8% of greenhouse gas emissions. In addition, the technology can accommodate the recycling of various pre-existing waste materials, which in return helps large utility and industrial companies transform financial and environmental liabilities into infrastructure assets to support their transition to a fully circular economic approach.
During lifting, electricity is stored as gravitational potential energy in the blocks, and on lowering, the stored potential energy drives a motor generator to regenerate electricity with as little loss as possible to maximize the efficiency of the process. The technological performance and commercial potential of this gravity-based system relative to other new entrants into the energy storage space was not apparent at the time, especially the levelized cost of electricity in $/MWh compared to lithium-ion batteries. Somehow, extremely tall cranes that lift and lower massive blocks in huge construction sites did not seem to be a practical global solution to grid-scale renewable energy storage. Fast forward to today and I have changed my mind. As of April 2022, Energy Vault became listed on the New York Stock Exchange, and with the breathtaking news of its latest gravitational energy storage system, it is one of the most exciting companies to watch. In just three years it has established an impressive global reach with its advanced gravity storage system on five continents, with more than US$32B earmarked projects over the next five years.
What has changed to elevate Energy Vault to such great heights? It’s simple: They have simplified their gravity storage system by integrating the lifting-and-lowering of heavy weights into a familiar “elevator” style building design that is compatible with all international building codes. Plus, they have perfected the manufacturing process of their eco-friendly and fully recyclable composite materials. The Energy Vault system literally can be built anywhere a building can be built. It is scalable on demand with no topological and geographical constraints, having flexible modular construction with the capacity to deliver GWs of power over short and long enough durations to handle solar and wind intermittency shortfalls. The energy storage system can also withstand harsh and changeable weather conditions, it is resilient to storage capacity degradation over time, not reliant on carbon intensive mining and refining of rare and toxic metals, and is devoid of chemical and fire safety risks. The round-trip efficiency or the proportion of stored to retrieved electricity is currently 83-85%, rather close to that of comparable power rating lithium-ion batteries, which hold 87-89%. Most importantly, it is purported to offer a lower levelized cost of electricity than any competing technology, particularly 60% of of today’s lithium-ion batteries — by 2025 this is projected to drop to 51%. This is one of the most promising sustainable solutions to global grid-scale renewable energy storage. It almost certainly will prove to be an indispensable piece of the circular economy puzzle, having a positive ripple effect on creating new clean technology industries and jobs, avoiding environmental liability, ameliorating climate change, and mitigating global warming. Now that’s what I call heavy lifting! |
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