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What are whistlers and how far can they reach?
🔘 A whistler is a very low frequency (VLF) radio wave generated by different types of lightning, including volcanic lightning.
🔘 These special electromagnetic waves are so named because they can be converted to sound signals and, with a VLF receiver, anyone can listen to the everyday melody of millions of lightning bolts (even if not every lightning bolt becomes a whistler). A listener in New Zealand can even hear a volcano in Alaska erupt.
🔘 Frequencies of terrestrial whistlers are 1 kHz to 30 kHz, with maximum frequencies usually at 3 kHz to 5 kHz.
🔘 For decades, researchers thought lightning-induced whistlers would remain trapped relatively close to Earth’s surface, below about 1,000 km.
⚡️ Now scientists have discovered that whistlers can reach distances up to 20,000 km above the planet’s surface, travelling deep into the highest layers of the atmosphere, where it could threaten the safety of satellites and astronauts.
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How many mass extinctions have there been and which one was the most devastating?
In the last 500 million years, five great mass extinction events have changed the face of life on Earth. We know what caused some of them, but others remain a mystery.
1️⃣ The Ordovician-Silurian mass extinction occurred 443 million years ago and wiped out approximately 85% of all species. Scientists think it was caused by temperatures plummeting and huge glaciers forming, which caused sea levels to drop dramatically. This was followed by a period of rapid warming. Many small marine species died out.
2️⃣ The Devonian mass extinction event took place 374 million years ago and killed about three-quarters of the world's species, most of which were marine invertebrates that lived at the bottom of the sea. This was a period of many environmental changes, including global warming and cooling, a rise and fall of sea levels and a reduction in oxygen and carbon dioxide in the atmosphere. We don't know exactly what triggered the extinction event.
3️⃣ The Permian mass extinction, which happened 250 million years ago, was the largest and most devastating event of the five. The Permian-Triassic extinction event is also known as the Great Dying. It eradicated more than 95% of all species, including most of the vertebrates which had begun to evolve by this time. Some scientists think Earth was hit by a large asteroid which filled the air with dust particles that blocked out the Sun and caused acid rain. Others think there was a large volcanic explosion which increased carbon dioxide and made the oceans toxic.
4️⃣ The Triassic mass extinction event occurred 200 million years ago, eliminating about 80% of Earth's species, including many types of dinosaurs. This was probably caused by colossal geological activity that increased carbon dioxide levels and global temperatures, as well as ocean acidification.
5️⃣ The Cretaceous mass extinction event occurred 66 million years ago, killing 78% of all species, including the remaining non-avian dinosaurs. This was most likely caused by an asteroid hitting the Earth in what is now Mexico, potentially compounded by ongoing flood volcanism in what is now India.
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How can plants cope with stresses and even “speak” to fungi?
Abiotic stresses, such as nutrient deficiency, drought, high temperature, and light stress, are significant limiting factors of plant survival and growth.
Scientists already knew that plant hormones (phytohormones), organic molecules that cause signaling effects in plant tissues, play an essential role in enhancing plant tolerance by responding to abiotic stresses.
But several recent studies have shown that strigolactones (SLs), carotenoid derivatives that occur naturally in plants, are novel phytohormones that regulate plant metabolism and growth, and help to cope with various stresses, e.g. by initiating physiological responses against drought stress.
SLs are also crucial for the interaction of plants with soil microorganisms like fungi, providing inter-kingdom communication.
In addition to attracting microorganisms, SLs affect photosynthesis, bridge other phytohormones, induce metabolic compounds.
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Why are moiré patterns important for materials science?
The so-called moiré patterns are motifs that emerge when two repetitive structures are overlaid.
This phenomenon is well known from computer or TV screens: when looking at a finely striped pattern, e.g. on a shirt, the stripes do not look evenly spaced and seem to bend in some areas. While undesirable in this case, the moiré effect can indeed be surprisingly useful.
Two atomically thin materials can be overlapped to create a new material, in which the atomic structures of the two produce a moiré pattern.
Some of these moiré materials exhibit astonishing properties, drastically different from those of their components, which may be applied in science, e.g. in novel nano-electronic devices.
The term originates from a French word moiré, a type of textile, traditionally made of silk but now also made of cotton or synthetic fiber, with a rippled or "watered" appearance, by pressing two layers of the textile when wet.
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How many people live in cities today?
🏙 Today, about 4.6 billion or 57% of the more than 8 billion people worldwide live in urban areas, according to different sources.
🌇 By 2050 this proportion is expected to increase to 68%, adding another 2.5 billion people to urban areas.
🏙 Today, the most urbanized regions include Northern America (with 82% of its population living in urban areas in 2018), Latin America and the Caribbean (81%), Europe (74%) and Oceania (68%).
🌇 A UN report notes that future increases in the size of the world’s urban population are expected to be highly concentrated in just a few countries. Together, India, China and Nigeria will account for 35% of the projected growth of the world’s urban population between 2018 and 2050, adding respectively 416, 255 and 189 million urban dwellers.
🏙 At present there are 3️⃣4️⃣ cities worldwide with more than 10 million inhabitants.
🎉⬆️ World Cities Day, designated by the UN, is celebrated annually on 31 October.
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Do migratory birds save energy escaping winter?
✔️ Scientists have long surmised that birds migrate during winters to save energy: far away from the biting cold, birds would need to expend less energy to keep themselves warm.
✔️ A new study has shown that migratory lifestyle carries no added overall energy cost.
✔️ Scientists have found partially migratory Eurasian blackbirds (Turdus merula) ⬆️ migrating to warmer regions in winter didn’t save more energy compared to members of the same species that stayed behind.
✔️ To measure the birds’ heart rate and body temperature over the course of the winter, researchers used surgically implanted biologgers.
✔️ It was also found that migrating birds started saving energy for migration by lowering their heart rate and body temperature almost a month before their departure.
✔️ The research raises important questions on why birds migrate if there’s no energy benefit, and where the unaccounted energy is being used instead.
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What are some examples of the largest 3D-printed objects?
🛳 The largest 3D printed boat is 11.980 m and was achieved by Abu Dhabi Maritime and Al Seer Marine (both UAE), in Abu Dhabi, UAE, on 6 Nov 2023 ⬆️.
⬛️ The largest 3D-printed structure (volume) is a wall with an outer shell and an inner filling that consists of 11.07 m³ of 3D-printed material and was achieved by Dubai Municipality (UAE), in Dubai, on 16 Oct 2019.
⚙️ The largest functional object to be 3D-printed in metal is a key jet engine component called a turbofan, measuring 1.5 m in diameter, printed in sections by Rolls-Royce and tested in July 2014.
🏠 The largest 3D printed villa is 303.42868 sq m (3266.079 sq ft) and was achieved by 3DXB Group, Dubai Municipality and Mohammed Bin Rashid Housing Establishment (all UAE) in Dubai, UAE, on 7 Dec 2023.
🏳️ The largest 3D-printed flag measures 16.2688 m² (175 ft² 11 in²), and was achieved by Anmar Gabra (KSA) in Makkah, Kingdom of Saudi Arabia, on 18 Aug 2024.
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What are the largest galaxy-made structures in the Universe?
ℹ️ Astrophysical jets are collimated streams of magnetized plasma produced by compact accreting objects, e.g. neutron stars or black holes.
When sustained for megayears (such long-lived coherence being yet unknown), these jets from supermassive black (SMBHs) holes become the largest galaxy-made structures in the Universe.
Named Porphyrion, after the king of giants in Greek mythology, the jets:
🌌stretch for around 23 million light-years – as long as 140 Milky Way galaxies
🌠are born at the heart of a galaxy located around 7.5 billion light-years away and are seen as they were when the 13.8 billion-year-old universe was just 6.3 billion years old
🔥put out trillions of times more energy per second than our sun does.
🌐 In terrestrial dimensions, this SMBH would have the size of 0.2 millimeters and the jets – the size of the Earth: an amoeba that generates a powerful fountain of energy the size of the entire planet!
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How many main types of batteries are there?
There are 2️⃣ main types of batteries:
🔋 Primary batteries, also known as non-rechargeable batteries, are designed and manufactured in the charged state for single use. Once their energy is depleted, they need to be replaced. Notable examples are alkaline batteries and lithium metal batteries.
🔋 Secondary batteries, also known as rechargeable batteries or accumulators, can be recharged after being discharged by reversing the flow of current through the battery and are usually assembled in the discharged state. They can be reused until the end of their useful life and their materials can be recycled. Secondary batteries are therefore more environmentally friendly and cost-effective than primary batteries. Examples are nickel–metal hydride (NiMH) batteries, lead–acid batteries, Li–ion batteries and solid-state batteries.
ℹ️✍️ Any device that can transform its chemical energy into electrical energy can be called a battery.
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Who invented the battery?
In 1800, Allesandro Volta, Italian physicist and chemist (1745-1827) made and introduced the first successful demonstration of a modern battery, commonly referred to as the Voltaic pile.⬆️
This device consisted of a series of zinc and silver plates stacked together, with each plate separated by a cloth soaked in a solution of acid and salt.
This invention paved the way for revolutionary advancements in long-distance communication, including the development of telegraphs in the late 1830s and the telephone in the 1870s.
However, the original Voltaic pile encountered a challenge due to the development of hydrogen bubbles as a result of chemical reactions that adhered to the electrode surfaces. This issue led to a rapid decline in the performance of the battery, rendering it of limited practical use.
ℹ️ The term "battery" was coined by Benjamin Franklin in 1749 to describe a set of linked capacitors he used for his experiments with electricity.
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What factors and mechanisms allow certain cells to keep working after an organismal death and why is it important to study the third state?
Postmortem conditions
🔳 Several factors influence whether certain cells and tissues can survive and function after an organism dies. These include environmental conditions, metabolic activity and preservation techniques.
🔳 Different cell types have varying survival times. For example, in humans, white blood cells die between 60 and 86 hours after organismal death. In mice, skeletal muscle cells can be regrown after 14 days postmortem, while fibroblast cells from sheep and goats can be cultured up to a month or so postmortem.
🔳 Metabolic activity plays an important role in whether cells can continue to survive and function. Active cells that require a continuous and substantial supply of energy to maintain their function are more difficult to culture than cells with lower energy requirements. Preservation techniques such as cryopreservation can allow tissue samples such as bone marrow to function similarly to that of living donor sources.
🔳 Inherent survival mechanisms also play a key role in whether cells and tissues live on. For example, researchers have observed a significant increase in the activity of stress-related genes and immune-related genes after organismal death, likely to compensate for the loss of homeostasis. Moreover, factors such as trauma, infection and the time elapsed since death significantly affect tissue and cell viability.
🔳 Factors such as age, health, sex and type of species further shape the postmortem landscape. This is seen in the challenge of culturing and transplanting metabolically active islet cells, which produce insulin in the pancreas, from donors to recipients. Researchers believe that autoimmune processes, high energy costs and the degradation of protective mechanisms could be the reason behind many islet transplant failures.
🔳 How the interplay of these variables allows certain cells to continue functioning after an organism dies remains unclear. One hypothesis is that specialized channels and pumps embedded in the outer membranes of cells serve as intricate electrical circuits. These channels and pumps generate electrical signals that allow cells to communicate with each other and execute specific functions such as growth and movement, shaping the structure of the organism they form.
🔳 The extent to which different types of cells can undergo transformation after death is also uncertain. Previous research has found that specific genes involved in stress, immunity and epigenetic regulation are activated after death in mice, zebrafish and people, suggesting widespread potential for transformation among diverse cell types.
Implications for biology and medicine
✔️ The third state not only offers new insights into the adaptability of cells. It also offers prospects for new treatments.
✔️ For example, anthrobots could be sourced from an individual’s living tissue to deliver drugs without triggering an unwanted immune response. Engineered anthrobots injected into the body could potentially dissolve arterial plaque in atherosclerosis patients and remove excess mucus in cystic fibrosis patients.
✔️ Importantly, these multicellular organisms have a finite life span, naturally degrading after four to six weeks. This “kill switch” prevents the growth of potentially invasive cells.
✔️ A better understanding of how some cells continue to function and metamorphose into multicellular entities some time after an organism’s demise holds promise for advancing personalized and preventive medicine.
ℹ️ Usually, scientists consider death to be the irreversible halt of functioning of an organism as a whole.
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Which planet in the solar system may once have had a ring like Saturn?
Surprisingly but it’s Earth that may have sported a Saturn-like ring system 466 million years ago, after it captured and wrecked a passing asteroid, a new study suggests.
The debris ring, which likely lasted tens of millions of years, may have led to global cooling and even contributed to the coldest period on Earth in the past 500 million years.
Using computer models of how our planet's tectonic plates moved in the past, scientists analyzed 21 crater sites around the world (across modern Australia, China, Europe, India, North America and Russia) that researchers suspect were all created by falling debris from a large asteroid between 488 million and 443 million years ago, an era in Earth's history known as the Ordovician during which our planet witnessed dramatically increased asteroid impacts.
ℹ️Saturn isn’t the only planet with rings. Jupiter, Neptune and Uranus have less obvious rings, too.
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Where do lavas originate from?
Lavas from hotspots likely originate from a worldwide, uniform reservoir in Earth's mantle, according to a new research.
The findings indicate Earth's mantle is far more chemically homogenous than scientists previously thought - and that lavas only acquire their unique chemical "flavours" enroute to the surface, interacting with different types of rocks.
Besides shedding entirely new light on hotspot lavas in oceanic parts of the world, the analysis also revealed an exciting new link to basaltic lavas on the continents. These melts, which contain diamond-bearing kimberlites, are fundamentally different from magmas found at oceanic hotspots. They nevertheless prove to have the same magma "ancestor."
ℹ️ A hotspot is a large plume of hot mantle material rising from deep within the Earth. A line of volcanoes develops as a plate moves over a hotspot, much as a line of melted wax forms as a sheet of waxed paper is moved slowly over a burning candle.
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What clouds are rare and form in unique ways?
Lenticular, or lee wave, clouds
▫️are lens-shaped and often look like flying saucers
▫️form downwind of an obstacle, e.g. a mountain, in the path of a strong air current
▫️seem to stay in one place, even though air is moving through the cloud, unlike other types of clouds.
Kelvin-Helmholtz clouds
▫️look like breaking waves in the ocean
▫️form when there is a difference in the wind speed or direction between two wind currents in the atmosphere and complex evaporation and condensation patterns create the capped tops and cloudless troughs of the waves.
Mammatus clouds
▫️are pouches of clouds that hang underneath the base of a cloud
▫️are most often associated with cumulonimbus clouds that produce very strong storms
▫️usually form during warm months, and are formed by descending air in the cloud.
▫️look like a field of tennis balls or melons, or like female human breasts ('mammatus' in Latin means ‘mamma’, or ‘breast’)
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What are the main characteristics of mid-level clouds?
Altocumulus clouds
▫️are mid-level, grayish-white with one part darker than the other
▫️usually form in groups and are about one kilometer thick
▫️are about as wide as your thumb when you hold up your hand at arm's length
▫️may be an indicator of a thunderstorm by late afternoon if seen on a warm, humid morning.
Altostratus clouds
▫️are mid-level, gray or blue-gray clouds
▫️usually cover the whole sky
▫️may be an indicator of a storm with continuous rain or snow.
The Sun or moon may shine through an altostratus cloud, but will appear watery or fuzzy. Occasionally, rain falls from an altostratus cloud. If the rain hits the ground, then the cloud has become a nimbostratus.
Nimbostratus clouds
▫️are dark gray, have ragged bases and sit low in the sky
▫️are associated with continuous rain or snow.
▫️sometimes cover the whole sky so that one can't see the edges of the cloud.
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What is the closest exoplanet that might have an ocean of liquid water?
The exoplanet LHS 1140 b is one of the closest discovered planets that lies within its star’s habitable zone — the region where a planet could retain liquid water – and might have an atmosphere and an ocean of liquid water.
⬆️ According to an international scientists’ team, LHS 1140 b might be what’s called an eyeball planet, with a single liquid ocean surrounded by ice. Or it might be entirely ice-covered, with an ocean below the ice, similar to Jupiter’s moon Europa or Saturn’s moon Enceladus.
Located only 48-49 light-years away in the constellation Cetus, LHS 1140 b is 1.7 times the size of our planet Earth and is the most promising habitable zone exoplanet yet in search for liquid water beyond the Solar System.
The team hopes to determine the planet’s surface characteristics and delve deeper into its atmosphere. It will likely take years to obtain all the needed data.
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What is the difference between a “normal” and a mass extinction?
✔️ Extinction is a part of life, and animals and plants disappear all the time.
✔️ When a species disappears, scientists say that a species goes extinct.
✔️ From an evolutionary perspective, the role of species that become extinct in the ecosystem is usually filled by new species, or other existing ones.
❗️ Earth's 'normal' extinction rate is often thought to be somewhere between 0.1 and 1 species per 10,000 species per 100 years. This is known as the background rate of extinction.
✔️ However, during the history of life on Earth, there have been periods of mass extinction.
❗️ A mass extinction event is when species vanish much faster than they are replaced. This is usually defined as about 75% of the world's species being lost in a short period of geological time - less than 2.8 million years.
ℹ️ About 98% of all the organisms that have ever existed on our planet are now extinct.
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What organisms are holobionts?
According to modern scientists, organisms are holobionts, and life is sympoietic.
The term “holobiont” refers to the scientific conclusion that organisms are integrated consortia of a host organism plus numerous species of other symbiotic organisms.
With few (if any) exceptions, animals and plants are holobionts, federated partnerships of numerous species functioning together to generate a healthy organism.
For example:
🧍♂️🧍♀️In the adult human body, microbes account for approximately half of cells, and these bacteria, fungi, protists, and archaea are critical for healthy physiology, development, and immunity.
🐄 Cows are herbivores, but there are no genes in their bovine nuclei that encode grass-digesting enzymes, and these cellulose-digesting enzymes come from the set of microbes living within the rumen of the cattle’s guts.
🪸 In coral, most of the animal’s carbon resources are derived from the photosynthetic reactions of its algal symbionts.
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How to collect energy from raindrops?
💦 Raindrops falling from the sky can produce a small amount of energy that can be harvested and turned into electricity.
Researchers have recently proposed several different devices for harvesting such dispersed hydropower.
One of the last inventions is a superhydrophobic magnetoelectric generator (MSMEG) ⬆️.
It consists of 5️⃣ parts:
📍a superhydrophobic magnetic material-based film (SMMF)
📍a coil
📍a NdFeB magnet
📍an acrylic housing
📍an expandable polystyrene (EPS) base.
According to scientists, the MSMEG can quickly charge a commercial capacitor with 2.7 V/1 F to 1.18 V within 200 seconds and power diverse electronic devices, e.g. LEDs and fans.
The authors of this study believe that such an MSMEG may provide a promising strategy for efficiently harvesting dispersed raindrop energy.
However, there are also opinions that such technologies are difficult to develop on a large scale and have limited practical application.
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What is the minimum of light required for plants to grow?
🌿☀️ Plants can grow with much less light than previously thought, according to a new study.
✅ Researchers lowered light sensors into Arctic water to a depth of 50 metres (164 feet) to test how low light levels must become before plant life ceases to exist and found that tiny water-based organisms called microalgae were able to perform photosynthesis with very little light ⬆️.
✅ The microalgae carry out this process at the lowest light levels ever recorded – just 0.04 micromoles of photons.
✅ This isn’t very far from what computer simulations predict to be the lowest light possible in any circumstances – 0.01 micromoles of photons.
✅ Typical light conditions outside on a clear day are between 1,500-2,000 micromoles of photons – more than 37,000-50,000 times the amount of light required by those microalgae.
ℹ️ This research can potentially make it easier to grow plants in areas with little sunlight and even in space.
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What are some examples of the smallest 3D-printed items?
🛳 The smallest boat ever sailed is a 11.5-micrometer-long – 0.0004-inch, about one-third of the thickness of a human hair – and is 3D-printed ⬆️. This tiny ship, named for a popular 3D-printing test "3DBenchy", was made by a team at Leiden University, the Netherlands in 2020. The scientists created the boat in a bid to enrich their research on microswimmers, or small particles that move in liquid.
🪧 The smallest 3D-printed billboard is 1.424 square millimetres (0.002 square inches), and was made by Kao Commercial, in Shanghai, China, in December 2021 ⬆️.
🗺 Scientists have created an accurate 3D map of the Earth that is so small that one-thousand of them could fit on one grain of salt. Patterns of the Earth’s continents were created using an incredibly sharp silicon knife to carve features as small as 15 nanometres on a polymer substrate measuring only 22 by 11 micrometres ⬆️.
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When was 3D printing invented?
📌The 1980s were a dynamic period in the history of 3D printing.
📌In 1981, a Japanese inventor Dr. Hideo Kodama paved the way for 3D printing technologies. He laid the foundation for additive manufacturing and developed a system for creating three-dimensional objects through a layer-by-layer approach using photosensitive resins.
📌In 1984, a US inventor Charles (Chuck) Hull patented filed the first patent for 3D printing – the Stereolithography process, the first commercial 3D printing technology and introduced the concept of layer-by-layer fabrication, which is fundamental to modern 3D printers.
📌Before emerging in a laboratory, 3D printing was described in science fiction:
✍️in 1945, in his “Things Pass By” Murray Leinster’s envisaged a constructor that used “magnetronic plastics” for fabricating articles from scanned drawings
✍️in 1950, Raymond F. Jones introduced the idea of a “molecular spray” to create items in his “Tools of the Trade”.
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Is there a battery that can last for decades?
☢️🔋 A nuclear battery powered by radioactive decay can last for decades.
Researchers have wanted to use radioactive atoms to build exceptionally long-lasting and damage-resistant batteries since the 1900s. But all prototypes were not very efficient.
Chinese scientists have improved the efficiency of a nuclear battery design by a factor of 8000.
The researchers used americium that is usually considered to be nuclear waste and radiates energy in the form of alpha particles, which carry lots of energy but quickly lose it to their surroundings. They embedded americium into a polymer crystal that converted this energy into a sustained and stable green glow.
Although americium has a half-life of 7380 years, this micronuclear battery ⬆️ should run for several decades, because the components surrounding the sample will eventually be destroyed by the radiation.
The battery may be used for deep-sea exploration and space missions.
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What are the major advancements in battery development after Voltaic pile?
Daniel cell (1836): English chemist, John Daniel (1790-1845) solved the performance degradation of the Voltaic pile in 1836 with the discovery of a two-fluid battery, named a Daniel cell. The system, consisted of a glass jar with a zinc anode on top and a copper cathode at the bottom. A two-layered liquid of concentrated CuSO4 and dilute H2SO4 was used as the electrolyte. It was commercially exploited mostly for powering telegraphs until the late 19th century when the introduction of other novel designs overshadowed its prominence. Daniel cell was a non-rechargeable battery.
Lead–acid storage cell (1854): German physicist Wilhelm Josef Sinsteden (1803-1891) in 1854, brought to light the concept of rechargeable batteries by utilizing two lead sheets in a container of dilute H2SO4. Soon after, in 1859, French physicist, Gaston Planté (1834-1889) introduced the first rechargeable lead-acid battery that revolutionized the world. It consisted of a dual sheet of lead with a rubber strip between them as a separator, which was again rolled into a spiral and immersed in dilute H2SO4 electrolyte.
Leclanché cell (1866): In 1866, George Leclanché (1839-1882), a French physicist, introduced several significant innovations and deviations from the prevailing approach of that time. He developed a new type of battery that utilized MnO2 as one of the electrodes, marking the first use of an oxide for this purpose. Lead oxide was not incorporated into the design of lead-acid batteries until 1881. The telegraphic service of Belgium swiftly adopted this technology in 1867. Leclanché also introduced the use of NH4Cl solution as the electrolyte, which diverged from the prevailing practice of employing protonic acids.
Dry cell (1886): Carl Gassner (1855-1942), in 1886, replaced the liquid NH4Cl solution in the Leclanché cell with a paste of NH4Cl solution mixed with plaster of Paris, creating the first significant dry cell. Gassner's invention was patented in multiple countries. During the same period, there were also independent developments of dry batteries (e.g. by Wilhelm Hellesen and Yai Sakizo), so the precise attribution of who invented the first dry cell remains somewhat unclear.
Nickel–cadmium cell (1899): Swedish scientist Waldemar Jüngner (1869-1924) introduced the nickel–cadmium battery in 1899, which was the first alkaline battery. It quickly became renowned as the ideal battery technology for small consumer devices. This technology was praised for its high current capacity and the ability to undergo numerous charging-discharging cycles. However, it finally lost popularity due to its high cost, degradation of the electrolyte, reduced battery lifespan and the toxic nature of cadmium.
Nickel–iron cell (1901): In addition to his work on nickel-cadmium batteries, Jüngner also introduced nickel-iron batteries.
Nickel–metal hydride cells (1967): The unpopularity of cadmium encouraged the development of nickel−metal hydride batteries in 1967, which are not only cadmium-free but can store more charge than nickel-cadmium batteries. On the downside, nickel-metal hydride batteries deliver less power, have a faster self-discharge and are less tolerant to overcharge. They found wide applications in mobile phones, computers and portable electronic goods after their commercialization in 1991.
Lithium cells (1970): Lithium-based batteries were the last to emerge in the progression of battery technology, only introduced in the 1970s by various research groups. The concept of lithium-ion (Li–ion) batteries was initially discussed around 1979 after which significant advancements were made, starting in 1980.
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What is the “Baghdad Battery”?
🔋 Batteries are perhaps the most prevalent and oldest forms of energy storage technology in human history.
🔋 In 1938, Wilhelm Konig, a German archaeologist, unearthed earthenware jars of approximately the size of a human fist at Khujut Rabu, located near Bagdad, modern Iraq. These 2,200-year-old jars were comprised of an iron rod within a copper cylinder, sealed with an asphalt stopper.
🔋 It is speculated that these jars were utilized by the inhabitants of the Parthian civilization, which governed the region 2,000 years ago, as electrical batteries for electroplating gold onto silver.
🔋 According to researchers, this ancient battery could produce electric current of approximately two volts.
🔋 This assemblage has become known as the “Bagdad Battery”.
❗️ However, it is important to note that there is currently no concrete evidence supporting this speculation, and even the dating of these artifacts remains somewhat disputed.
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What life-forms can emerge after death?
In a new study, scientist expanded knowledge about so-called “third state” that lies beyond the traditional boundaries of life and death.
Researchers described how certain cells – when provided with nutrients, oxygen, bioelectricity or biochemical cues – have the capacity to transform into multicellular organisms with new functions after death.
It was found that:
📌 skin cells extracted from deceased frog embryos were able to adapt to the new conditions of a petri dish in a lab, spontaneously reorganizing into multicellular organisms called xenobots ⬆️
📌 solitary human lung cells can self-assemble into miniature multicellular organisms – anthrobots – that behave and are structured in new ways, being able not only able to navigate their surroundings but also repair both themselves and injured neuron cells placed nearby.
These findings challenge the idea that cells and organisms can evolve only in predetermined ways.
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How many “hidden turbulences” in Van Gogh's “Starry Night”?
The illusion of movement in “The Starry Night” is so vivid that scientists analyzed how closely van Gogh’s depiction mirrors the actual physics of atmospheric turbulence.
They discovered two “hidden turbulences”:
1️⃣the sizes of the 14 whirls or eddies and their relative distance and intensity, follow a physical law known as Kolmogorov’s theory of turbulence.
ℹ️In the 1940s, Soviet Russian mathematician Andrey Kolmogorov (1903-1987) described a mathematical relationship between the fluctuations in a flow’s speed and the rate at which its energy dissipates.
2️⃣the paint, at the smallest scale, mixes around with some background swirls and whirls in a fashion predicted by turbulence theory, following a statistical pattern known as Batchelor’s scaling.
ℹ️Batchelor’s scaling mathematically represents how small particles (drifting algae in the ocean or pieces of dust in the wind) are passively mixed around by turbulent flow.
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Why is morning wiser than evening?
People are easily seduced by first impressions, even when they turn out to be inaccurate.
At the same time, expressions like ‘morning is wiser than evening’ or ‘one should sleep on it’ exist in many cultures and languages.
According to a new study, sleeping on it can really help people avoid judging a book solely by its cover.
In “garage sale” experiments, the researchers asked participants to look through virtual boxes. All boxes were equally valuable, but rewards were either evenly distributed or clustered at the beginning, middle, or end of the sequence. A pattern (a psychological phenomenon called primacy bias) quickly emerged: when the participants had to make a decision right away, they tended to believe that some boxes were more valuable than they really were. However, participants who weren’t asked to decide until the next day were less likely to fall into these traps and made more rational choices.
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What are the main characteristics of low-level clouds?
Cumulus clouds
▫️have vertical growth
▫️are puffy white or light gray clouds looking like floating cotton balls
▫️have sharp outlines and a flat base at a height of 1000m
▫️are generally about 1km wide
▫️can be associated with fair or stormy weather.
Cumulonimbus clouds
▫️have vertical growth and can grow up to 10 km high, where they have an anvil-like shape because of high winds
▫️are thunderstorm clouds and are associated with heavy rain, snow, hail, lightning, and sometimes tornadoes.
Stratus clouds
▫️are low and have a uniform gray in color
▫️can cover most or all of the sky
▫️can look like a fog that doesn't reach the ground.
Light mist or drizzle is sometimes falling when stratus clouds are in the sky.
Stratocumulus clouds
▫️are low, lumpy, and gray
▫️can line up in rows and also spread out
▫️may be confused with higher altocumulus clouds.
Only light rain (usually drizzle) falls from stratocumulus clouds.
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What are the main characteristics of high-level clouds?
Cirrus clouds are
▫️made of ice crystals and look like long, thin, wispy white streamers high in the sky
▫️commonly known as "mare's tails" because they are shaped like the tail of a horse
▫️often seen during fair weather (but if they are followed by cirrostratus clouds, there may be a warm front on the way).
Cirrocumulus clouds are
▫️small rounded puffs that usually appear in long rows high in the sky
▫️usually white, but sometimes appear gray
▫️often called a "mackerel sky” as they can look like the scales of a fish when covering a lot of the sky
▫️common in winter indicating fair, but cold, weather.
Cirrostratus clouds are
▫️high, thin sheet-like thin clouds that usually cover the entire sky
▫️so thin that the Sun or moon can sometimes shine through and appear to have a halo as light hits the ice crystals and bends.
▫️usually seen 12 to 24 hours before a rain or snowstorm.
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