Nanometer to Ri (Japanese) Converter
Convert nanometers to ri with our free online length converter.
Quick Answer
1 Nanometer = 2.546473e-13 ri
Formula: Nanometer × conversion factor = Ri (Japanese)
Use the calculator below for instant, accurate conversions.
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Nanometer to Ri (Japanese) Calculator
How to Use the Nanometer to Ri (Japanese) Calculator:
- Enter the value you want to convert in the 'From' field (Nanometer).
- The converted value in Ri (Japanese) will appear automatically in the 'To' field.
- Use the dropdown menus to select different units within the Length category.
- Click the swap button (⇌) to reverse the conversion direction.
How to Convert Nanometer to Ri (Japanese): Step-by-Step Guide
Converting Nanometer to Ri (Japanese) involves multiplying the value by a specific conversion factor, as shown in the formula below.
Formula:
1 Nanometer = 2.5465e-13 riExample Calculation:
Convert 10 nanometers: 10 × 2.5465e-13 = 2.5465e-12 ri
Disclaimer: For Reference Only
These conversion results are provided for informational purposes only. While we strive for accuracy, we make no guarantees regarding the precision of these results, especially for conversions involving extremely large or small numbers which may be subject to the inherent limitations of standard computer floating-point arithmetic.
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View all Length conversions →What is a Nanometer and a Ri (Japanese)?
A nanometer (symbol: nm) is a unit of length in the International System of Units (SI) equal to one billionth (10⁻⁹) of a meter:
1 nm = 0.000000001 m = 1 × 10⁻⁹ m
Why Is the Nanometer Scale Special?
The nanometer occupies a unique position between the atomic world and the microscopic world visible under optical microscopes:
1. Atomic to Molecular Scale:
- Individual atoms: 0.1-0.3 nm diameter (hydrogen to larger elements)
- Small molecules: 0.3-2 nm (water, glucose, amino acids)
- Large biomolecules: 2-100 nm (proteins, DNA, ribosomes)
2. Quantum Effects Dominate:
- At nanometer scales, quantum mechanical effects become significant
- Electrons exhibit wave-particle duality
- Quantum tunneling allows particles to pass through barriers
- Energy levels become quantized (discrete rather than continuous)
- Materials exhibit size-dependent properties (quantum dots change color with size)
3. Surface Area to Volume Ratio:
- Nanoparticles have enormous surface area relative to volume
- This makes them extremely reactive and useful for catalysis
- Example: Gold is chemically inert in bulk but highly reactive as 5nm nanoparticles
4. Optical Properties Change:
- Materials interact differently with light at nanometer scales
- Nanostructures can manipulate light in ways impossible with bulk materials
- Metamaterials with negative refractive index
- Plasmonic effects in metal nanoparticles
The Nanometer in Context
Too Small to See with Optical Microscopes:
- Optical microscopes use visible light (wavelengths 400-700nm)
- Diffraction limit: Cannot resolve features smaller than ~200nm (half the wavelength)
- Viewing nanometer-scale structures requires:
- Electron microscopes (transmission or scanning, resolution to 0.1nm)
- Scanning probe microscopes (STM, AFM, can "feel" individual atoms)
- X-ray crystallography (infers structure from diffraction patterns)
Larger Than Individual Atoms:
- Atoms: 0.1-0.3nm diameter
- Nanometer scale: 1-100nm (roughly 3-300 atoms wide)
- This is the realm of molecules, nanoparticles, viruses, and proteins
The Ri (里) is a traditional Japanese unit of long distance, belonging to the Shakkanhō (尺貫法) system. It is defined as being equal to 36 chō (町).
Based on the standardized chō (which is 60 ken, with 1 ken = 6 shaku, and 1 shaku = 10/33 meters), the modern standardized Ri is equivalent to:
- 36 chō = 36 * (60 ken) = 36 * 60 * (6 shaku) = 12,960 shaku
- 12,960 * (10/33) meters = 129,600 / 33 meters = 43,200 / 11 meters
- Exactly 3927.2727... meters
- Approximately 3.927 kilometers (km)
- Approximately 2.440 miles (mi)
Historically, the Ri represented a significant travel distance, often conceptualized as roughly the distance a person could walk in one hour.
Note: The Nanometer is part of the metric (SI) system, primarily used globally in science and trade. The Ri (Japanese) belongs to the imperial/US customary system.
History of the Nanometer and Ri (Japanese)
of the Nanometer and Nanotechnology
Early Foundations: Unknowingly Working at the Nanoscale (Pre-1900)
Ancient Nanomaterials (400 BCE - 1600 CE):
- Roman Lycurgus Cup (4th century CE): Contains gold-silver nanoparticles (~70nm) that make glass appear red in transmitted light, green in reflected light
- Medieval stained glass windows: Colloidal gold and other metal nanoparticles create vibrant colors
- Ancient artisans unknowingly created nanomaterials through empirical recipes
Michael Faraday's Colloidal Gold (1857):
- British scientist Michael Faraday systematically studied colloidal gold suspensions
- Discovered that gold nanoparticles (5-100nm) exhibit ruby-red color, unlike bulk gold's yellow
- First scientific recognition that material properties change at nanometer scale
- Published "Experimental Relations of Gold (and Other Metals) to Light"
- Laid foundation for nanoscience, though the term wouldn't exist for over a century
Theoretical Foundations (1900-1959)
Quantum Mechanics (1900-1930):
- Max Planck (1900): Quantum theory—energy is quantized
- Albert Einstein (1905): Photons (light quanta) and photoelectric effect
- Niels Bohr (1913): Atomic model with discrete electron orbits
- Erwin Schrödinger (1926): Wave equation describing electron behavior
- These developments revealed that matter behaves fundamentally differently at atomic/molecular scales
Electron Microscopy (1931):
- Ernst Ruska and Max Knoll invented the transmission electron microscope (TEM)
- First images of structures below optical resolution (sub-100nm)
- Enabled visualization of viruses, cell organelles, and eventually nanoparticles
The Birth of Nanotechnology Concept (1959-1980)
Richard Feynman's Vision (1959):
- Famous lecture "There's Plenty of Room at the Bottom" at Caltech
- Envisioned manipulating individual atoms to build materials and machines
- Predicted writing entire Encyclopedia Britannica on head of a pin
- Proposed molecular-scale machinery and atom-by-atom fabrication
- Didn't use term "nanotechnology" but inspired the field
Norio Taniguchi Coins "Nanotechnology" (1974):
- Japanese scientist Norio Taniguchi first used term "nanotechnology"
- Referred to precision machining and material processing with tolerances below 1 micrometer
- Initially described top-down manufacturing (machining, lithography)
- Later expanded to bottom-up assembly (molecular self-assembly)
The Nanotechnology Revolution (1981-Present)
Scanning Tunneling Microscope - STM (1981):
- Gerd Binnig and Heinrich Rohrer (IBM Zurich) invented STM
- First instrument to "see" and manipulate individual atoms
- Uses quantum tunneling effect to scan surfaces with atomic resolution
- Won Nobel Prize in Physics (1986)
- 1989: IBM scientists arranged 35 xenon atoms to spell "IBM" (first atomic-scale manipulation)
Atomic Force Microscope - AFM (1986):
- Gerd Binnig, Calvin Quate, and Christoph Gerber invented AFM
- Can image and manipulate atoms on insulators (not just conductors like STM)
- "Feels" surface topography with nanometer-scale probe
- Revolutionized nanoscale characterization across materials science, biology, chemistry
Fullerenes and Carbon Nanotubes (1985-1991):
- Harold Kroto, Robert Curl, Richard Smalley discovered buckminsterfullerene (C₆₀, 1985)
- Soccer-ball-shaped carbon molecule, ~0.7nm diameter
- Nobel Prize in Chemistry (1996)
- Sumio Iijima discovered carbon nanotubes (1991)
- Cylindrical carbon structures, 1-100nm diameter, micrometers long
- Exceptional strength, electrical conductivity, thermal properties
- Sparked explosion of nanomaterials research
Semiconductor Nanometer Process Nodes (1990s-Present):
Moore's Law and the Nanometer Era:
- Gordon Moore (1965): Predicted transistor count per chip would double every ~2 years
- Drove relentless miniaturization of semiconductor features
Process Node Timeline:
- 130 nm (2001): Intel Pentium 4, first widespread "nanometer node"
- 90 nm (2004): AMD Athlon 64, Intel Pentium 4 Prescott
- 65 nm (2006): Intel Core 2 Duo, beginning of multi-core era
- 45 nm (2007): Intel Core 2 Duo (Penryn), high-k metal gates introduced
- 32 nm (2010): Intel Core i3/i5/i7 (Westmere)
- 22 nm (2012): Intel Ivy Bridge, first 3D FinFET transistors (non-planar)
- 14 nm (2014): Intel Broadwell, Apple A8
- 10 nm (2017): Intel Cannon Lake (limited), Samsung/TSMC volume production
- 7 nm (2019): AMD Ryzen 3000, Apple A12, extreme ultraviolet (EUV) lithography
- 5 nm (2020): Apple M1, AMD Ryzen 5000 (TSMC), advanced EUV
- 3 nm (2022): Apple M2 Pro/Max (late 2022), Apple A17 (2023)
- 2 nm (Development): Expected mid-2020s, pushing physical limits
Note: Modern "process nodes" (7nm, 5nm, 3nm) are marketing terms more than actual physical dimensions. A "5nm" chip doesn't necessarily have 5nm transistors; the smallest features may be 20-30nm. The naming reflects relative density improvements.
Contemporary Nanotechnology (2000-Present)
Nanomedicine:
- Nanoparticle drug delivery: Liposomes, polymeric nanoparticles target tumors
- mRNA vaccines (Pfizer-BioNTech, Moderna COVID-19 vaccines): Use lipid nanoparticles (~100nm) to deliver mRNA
- Gold nanoparticles for cancer therapy, diagnostics
- Quantum dots for biological imaging
Nanomaterials:
- Graphene (2004 isolation by Andre Geim and Konstantin Novoselov): Single-atom-thick carbon sheet, extraordinary properties
- Quantum dots: Semiconductor nanocrystals (2-10nm) that emit specific colors based on size
- Aerogels: Ultra-low-density nanoporous materials
Consumer Applications:
- Sunscreen: Titanium dioxide and zinc oxide nanoparticles (transparent, UV-blocking)
- Anti-reflective coatings: Nanoporous silica on eyeglasses, displays
- Stain-resistant fabrics: Nanoparticle coatings
- Catalytic converters: Platinum nanoparticles
- Origin: The Japanese Ri unit, like many elements of the Shakkanhō measuring system, originates from ancient China, where the equivalent unit is the Li (里). This traditional unit of distance was adopted into Japan centuries ago.
- Variable Length: For much of Japanese history, the precise length of the Ri was not consistently fixed. Its value varied significantly depending on the region, the era, and even the specific context (e.g., measuring distance on flat land versus mountainous terrain). Different feudal domains (han) might use slightly different standards. For instance, during the Edo period (1603–1868), while a standard of 36 chō per Ri was common, local variations persisted, making historical distance conversions complex.
- Standardization (Meiji Era): Following the Meiji Restoration, Japan undertook efforts to modernize and standardize its systems, including weights and measures. The Weights and Measures Act of 1891 officially defined traditional Japanese units in relation to metric standards. The base unit shaku was set at 10/33 meters, which in turn fixed the values of the ken, chō, and consequently the Ri. The Ri was officially standardized as 36 chō, leading to the modern, precise value of 43,200/11 meters (approximately 3.93 km).
- Metrication: Japan officially adopted the metric system in 1951, with full implementation for official and commercial transactions mandated in 1959. This shift means the Ri became largely obsolete for practical, everyday measurements, replaced by the kilometer.
Common Uses and Applications: nanometers vs ri
Explore the typical applications for both Nanometer (metric) and Ri (Japanese) (imperial/US) to understand their common contexts.
Common Uses for nanometers
of the Nanometer in Modern Contexts
1. Technology and Electronics
Semiconductors:
- Process node naming (3nm, 5nm, 7nm chips)
- Transistor gate lengths, interconnect widths
- Thin film thicknesses (oxides, metals, dielectrics)
Displays:
- QLED quantum dots (2-10 nm) for color purity
- OLED organic layers (~100 nm thick)
- Anti-reflective coatings (100-150 nm)
Data Storage:
- Hard drive head-to-platter spacing (~3-5 nm flying height)
- Magnetic domain sizes (~10-50 nm)
- Flash memory cell feature sizes (~15-30 nm)
2. Optics and Photonics
Wavelength Specifications:
- Laser wavelengths (UV: 193 nm, 248 nm, 355 nm; visible: 405 nm, 532 nm, 650 nm)
- Optical filter bandwidths (specify transmission/reflection in nm ranges)
- Spectroscopy (absorption/emission peaks reported in nanometers)
Thin Film Optics:
- Anti-reflective coatings (multiple layers, each 50-150 nm)
- Dichroic mirrors and filters (nanometer-scale multilayers)
- Photonic crystals (periodic structures, 100-500 nm)
3. Materials Science and Nanotechnology
Nanoparticle Synthesis:
- Specifying target particle size (gold nanoparticles: 5, 10, 20, 50, 100 nm)
- Quantum dots (size determines optical properties)
- Ceramic nanoparticles for catalysis, coatings
Thin Films and Coatings:
- Physical vapor deposition (PVD), chemical vapor deposition (CVD)
- Layer thicknesses: 1-1,000 nm
- Atomic layer deposition (ALD): atomic-scale control (~0.1 nm/cycle)
Surface Characterization:
- Atomic force microscopy (AFM) measures roughness in nanometers
- Ellipsometry measures film thickness (0.1-1,000 nm range)
- Scanning electron microscopy (SEM) images nanoscale features
4. Biology and Medicine
Molecular Dimensions:
- Protein sizes (5-50 nm typical)
- Virus dimensions (20-400 nm)
- Cell membrane thickness (~7-10 nm lipid bilayer)
Nanomedicine:
- Nanoparticle drug carriers (50-200 nm optimal for cellular uptake)
- mRNA vaccine lipid nanoparticles (~100 nm)
- Diagnostic nanoparticles (gold, quantum dots, magnetic)
Microscopy:
- Electron microscopy resolution (TEM: 0.1-1 nm, SEM: 1-10 nm)
- Super-resolution optical microscopy (breaks diffraction limit, ~20-50 nm resolution)
5. Environmental Science
Air Quality:
- Ultrafine particles: < 100 nm diameter (penetrate deep into lungs)
- PM 2.5: Particulate matter < 2,500 nm (2.5 μm) diameter
- Nanoparticle pollutants from combustion, industrial processes
Water Filtration:
- Nanofiltration membranes: pore sizes 1-10 nm (remove ions, small molecules)
- Graphene oxide membranes: sub-nanometer channels for desalination
6. Metrology and Precision Measurement
Surface Roughness:
- Optical surfaces: Roughness < 1 nm RMS (root mean square) for high quality
- Semiconductor wafers: < 0.1 nm RMS for epitaxial growth
Film Thickness:
- Quality control in manufacturing (coatings, semiconductors)
- Techniques: Ellipsometry, X-ray reflectivity, profilometry
7. Research and Development
Nanoscience Research:
- Synthesizing new nanomaterials with specific dimensions
- Characterizing structure-property relationships
- Exploring quantum effects at nanoscale
Academic Publications:
- Specifying material dimensions (nanoparticle size, film thickness, feature size)
- Nanometer is standard unit in materials science, nanotechnology, condensed matter physics
When to Use ri
While the kilometer (km) is the standard unit for measuring long distances in modern Japan, the traditional Ri unit retains significance in specific contexts:
- Historical Context: Understanding the Ri is essential for interpreting historical travel accounts, old maps (like those showing the Tōkaidō road), and administrative divisions from feudal Japan. Landmarks called ichirizuka (一里塚 - "one-ri mound") were placed along major highways during the Edo period to mark distances in Ri.
- Literature and Culture: The Ri appears frequently in classical Japanese literature, poetry (like haiku), and folklore, often used to denote long journeys or significant, sometimes metaphorical, distances.
- Place Names: Many place names across Japan incorporate "Ri," often stemming from historical distance markers or locations whose names indicated their distance in Ri from a provincial capital or castle.
- Idioms and Proverbs: The unit features in well-known sayings, such as 「千里の道も一歩から」 (Sen ri no michi mo ippo kara - "A journey of a thousand ri begins with a single step"), emphasizing that even great undertakings start with small actions.
- Figurative Language: Speakers might use Ri figuratively to imply a very long way, a great effort, or a significant difference.
It is crucial to remember that the Ri is not used for contemporary official measurements, modern road signs (which universally use kilometers), or everyday distance calculations in Japan today.
Additional Unit Information
About Nanometer (nm)
1. How small is a nanometer?
A nanometer is extraordinarily small—one billionth of a meter (0.000000001 m). To grasp this scale: A human hair is about 80,000-100,000 nm wide, so you could fit 80,000-100,000 nanometers across a single hair. A sheet of paper is ~100,000 nm thick. The DNA double helix is 2 nm wide. A typical protein molecule is 5-50 nm. A single gold atom is ~0.3 nm diameter, so 1 nanometer spans approximately 3-4 atoms. If a nanometer were enlarged to 1 centimeter, a meter would stretch 10,000 kilometers—farther than the distance from New York to Tokyo. At this scale, quantum mechanical effects dominate: electrons behave as waves, particles can tunnel through barriers, and material properties become size-dependent.
2. How many nanometers are in a micrometer?
There are exactly 1,000 nanometers in 1 micrometer (μm). The relationship: 1 μm = 1,000 nm, or 1 nm = 0.001 μm. This factor of 1,000 comes from the metric prefix system: micro (μ) = 10⁻⁶ and nano (n) = 10⁻⁹, so 10⁻⁶ ÷ 10⁻⁹ = 10³ = 1,000. Examples: A typical bacterium (E. coli) is 2 μm long = 2,000 nm. A red blood cell is 7-8 μm diameter = 7,000-8,000 nm. A virus is 20-400 nm = 0.02-0.4 μm. Human hair is 80 μm = 80,000 nm. The nanometer-to-micrometer boundary (~100-1,000 nm) roughly separates the realm of individual molecules and nanoparticles (nm) from the realm of cells and microorganisms (μm).
3. Why are nanometers important in technology?
Nanometers are the scale at which quantum mechanical effects emerge, enabling revolutionary technologies. At 1-100 nm, materials exhibit size-dependent properties impossible to achieve in bulk: gold nanoparticles turn red; semiconductor quantum dots emit precise colors based on size; carbon nanotubes become stronger than steel. Semiconductor chips have shrunk to 3-5nm process nodes, packing billions of transistors into fingernail-sized dies—enabling smartphones, AI, cloud computing. Nanometer precision allows atomic layer deposition (building materials atom-by-atom), molecular diagnostics (detecting single protein molecules), targeted drug delivery (100nm nanoparticles accumulate in tumors), and metamaterials (nanoscale structures that bend light impossibly). The nanometer sits at the sweet spot: large enough to fabricate with advanced tools (electron beam lithography, STM manipulation), small enough to exploit quantum effects and interact with individual molecules—making it the frontier of 21st-century technology.
4. What's the difference between a nanometer and an angstrom?
A nanometer (nm) equals 10 angstroms (Å). The angstrom (1 Å = 0.1 nm = 10⁻¹⁰ meters) was historically used in atomic physics, chemistry, and crystallography because atomic diameters and chemical bond lengths conveniently fall in the 1-5 Å range (hydrogen atom: ~1 Å, carbon-carbon bond: 1.54 Å). However, the angstrom is not an SI unit, and modern scientific practice favors nanometers and picometers. Example: The diameter of a DNA double helix is 2 nm = 20 Å. The spacing between DNA base pairs is 0.34 nm = 3.4 Å. A silicon atom is 0.21 nm = 2.1 Å diameter. While older papers and crystallography software often report structures in angstroms, nanometers are now standard in nanotechnology, materials science, and most contemporary research. If you see Å, just divide by 10 to convert to nanometers.
5. Can you see something that's 1 nanometer?
No, you cannot see 1 nanometer with any optical microscope, and barely even with your eyes' theoretical maximum resolution. Human eyes can resolve ~50-100 micrometers (50,000-100,000 nm) at best. Optical microscopes are limited by the diffraction limit—approximately half the wavelength of light used. Visible light ranges 400-700 nm, so the best optical resolution is ~200-300 nm (using UV light and oil immersion). To "see" 1 nm structures, you need: Transmission Electron Microscope (TEM): Uses electron beams (wavelength ~0.01 nm at high voltage), achieving 0.1-1 nm resolution—can image individual atoms. Scanning Tunneling Microscope (STM) or Atomic Force Microscope (AFM): "Feel" surfaces by scanning a sharp tip (1-atom-wide apex) across the sample, mapping topography with sub-nanometer precision. So yes, we can "see" nanometer and sub-nanometer features, but not with light—we use electrons or physical probes.
6. Why are modern chips called "3nm" or "5nm" when features aren't actually that small?
Modern process node names (3nm, 5nm, 7nm) are marketing terms reflecting relative density improvements, not actual physical dimensions. Historically, process nodes indicated the smallest feature size (e.g., Intel's 130nm process in 2001 had ~130nm gate lengths). But as scaling slowed and 3D transistor designs (FinFETs) emerged, the relationship broke down. Today: A "5nm" chip from TSMC might have gate lengths ~20-30nm, metal pitch ~30-40nm, and the tightest pitch structures ~24-28nm. The "5nm" refers roughly to an equivalent density compared to hypothetical scaling trends. A "3nm" chip is denser than "5nm," but actual dimensions are larger than 3nm. Why keep the naming? Industry convention, marketing (smaller number sounds more advanced), and rough correlation with transistor density. Different manufacturers' "5nm" may differ significantly. Bottom line: Process nodes indicate generation and relative performance/density, not literal nanometer measurements.
7. What's the smallest thing ever manipulated by humans?
Humans have manipulated individual atoms (~0.1-0.3 nm), the smallest stable units of matter. 1989: IBM scientists used a Scanning Tunneling Microscope (STM) to arrange 35 xenon atoms to spell "IBM" on a nickel surface—the first atomic-scale manipulation. 1990s-present: Researchers built molecular structures atom-by-atom: molecular gears, switches, quantum corrals (rings of atoms to confine electrons). 2012: Physicists stored 1 bit of data in a single holmium atom (~0.25 nm diameter) using magnetic orientation. Subatomic particles: Particle accelerators (LHC) manipulate protons (~0.0016 nm diameter) and study quarks (~10⁻³ to 10⁻⁴ nm, though quarks can't be isolated). Quantum engineering: Controlling individual electron spins, photon states, and qubits for quantum computing. So while atoms (~0.1-0.3 nm) are the smallest stable structures we manipulate routinely, we probe and control phenomena down to 10⁻⁵ nm scales in particle physics.
8. How does nanotechnology differ from regular technology?
Nanotechnology operates at 1-100 nm scale where quantum mechanical effects become significant and surface-area-to-volume ratios are enormous, enabling properties impossible in bulk materials. Differences: Scale: Nanotech manipulates individual molecules, atoms, or nanostructures; regular tech uses bulk materials. Quantum effects: At nanoscale, quantum tunneling, quantized energy levels, and wave-particle duality dominate; bulk materials follow classical physics. Size-dependent properties: Gold nanoparticles (5-50 nm) are red/purple and reactive; bulk gold is yellow and inert. Quantum dots (2-10 nm) emit precise colors tuned by size—impossible with bulk semiconductors. Surface area: Nanoparticles have immense surface area relative to volume, making them superb catalysts, drug carriers, and sensors. Bottom-up assembly: Nanotech often uses molecular self-assembly or atom-by-atom fabrication; traditional manufacturing is top-down (machining, cutting). Applications: Nanotech enables mRNA vaccines (lipid nanoparticles), 3nm computer chips, targeted cancer therapy, and quantum computing—revolutionary advances impossible with conventional approaches.
9. Is nanotechnology safe?
Nanotechnology safety is highly material-specific—some nanomaterials are safe, others pose risks. Concerns: 1) Toxicity: Some nanoparticles (carbon nanotubes, certain metal oxides) can damage cells, cause inflammation, or penetrate biological barriers (blood-brain barrier). Silver nanoparticles, widely used in antimicrobial products, can harm aquatic life. 2) Environmental persistence: Nanoparticles may accumulate in ecosystems with unknown long-term effects. 3) Inhalation: Ultrafine airborne nanoparticles (~10-100 nm) penetrate deep into lungs, potentially causing respiratory issues. Safety measures: Extensive testing: New nanomaterials undergo toxicology studies before commercial use. Regulation: FDA, EPA, EU regulate nanomaterials in drugs, food, cosmetics, and industrial applications. Encapsulation: Many nanoparticles (e.g., in sunscreen, food) are embedded in matrices, preventing release. Established safety: Some nanomaterials are demonstrably safe (titanium dioxide and zinc oxide in sunscreen used for decades; lipid nanoparticles in mRNA vaccines tested extensively). Conclusion: Nanotech isn't universally safe or dangerous—each material requires careful evaluation.
10. How do semiconductor fabs create nanometer-scale features?
Modern semiconductor fabrication uses photolithography with extreme precision and multi-step patterning. Extreme Ultraviolet (EUV) Lithography: Uses 13.5 nm wavelength light (generated by tin plasma) to pattern features. Wavelength is much smaller than older 193 nm UV lithography, enabling finer patterns. Process: 1) Coat silicon wafer with photoresist (~50-100 nm layer). 2) Project circuit pattern onto resist using EUV light through precision optics. 3) Exposed resist dissolves, leaving pattern. 4) Etch exposed silicon, deposit materials, etc. 5) Repeat hundreds of times (modern chips: 20-25+ mask layers). Multi-patterning: Single exposure can't achieve tightest pitches, so features are created through multiple aligned exposures (self-aligned double patterning, etc.). Atomic Layer Deposition (ALD): Deposits ultra-thin films (~0.1-1 nm precision) for gates, insulators. FinFET 3D transistors: Vertical silicon fins (~5-7 nm wide) provide better gate control at nanoscale. Extreme precision: Alignment accuracy: ~1-2 nm. Temperature control: ±0.01°C. Cleanrooms: <1 particle/cubic meter. Took decades of R&D and billions in equipment development to achieve 3-5nm nodes.
11. What's the limit of miniaturization in computer chips?
Miniaturization faces several fundamental limits expected to halt around 1-2 nm nodes (late 2020s-early 2030s): 1) Atomic scale: Silicon atoms are ~0.21 nm diameter. At 1-2 nm features, structures are just 5-10 atoms wide—difficult to control dopant placement and variability. 2) Quantum tunneling: Electrons can "tunnel" through barriers < 1-2 nm thick, causing leakage current and preventing transistors from turning off. 3) Heat dissipation: Power density in chips approaches limits of cooling technology. Shrinking further increases current density and heat. 4) Manufacturing precision: Atomic-level variations affect device performance. Placing individual dopant atoms precisely is extremely difficult. Beyond silicon: Future options include: New materials (carbon nanotubes, graphene, 2D materials). 3D stacking (vertical integration). New transistor architectures (gate-all-around FETs, tunnel FETs). Beyond CMOS (quantum computing, photonic computing, neuromorphic chips). Moore's Law (doubling transistor count every 2 years) is already slowing. The 1 nm node may be the practical limit for silicon, necessitating entirely new computing paradigms.
12. Can nanotechnology create molecular machines?
Yes! Molecular machines—nanometer-scale structures that perform mechanical work—exist naturally and are being engineered artificially. Natural molecular machines: Ribosomes (~20 nm): Synthesize proteins, translating mRNA into amino acid chains (Nobel Prize 2009 for structure determination). ATP synthase (~10 nm): Rotary motor in mitochondria, spins at ~100 Hz to produce ATP (cellular energy currency). Kinesin motors (~10 nm): "Walk" along microtubules, transporting cargo within cells. DNA polymerase: Copies DNA, moving along strands, proof-reading, and assembling nucleotides. Synthetic molecular machines (Nobel Prize in Chemistry 2016): Molecular motors: Light-driven rotors, chemically-driven linear motors (synthesized by Fraser Stoddart, Jean-Pierre Sauvage, Ben Feringa). DNA origami machines: Programmable nanoscale structures that fold, unfold, or grasp objects. Potential applications: Nanoscale drug delivery, molecular computing, self-assembling materials, targeted cell repair. Challenges: Operating in biological environments, controlling motion precisely, scaling up production. Molecular machines are early-stage but represent frontier of nanotechnology.
About Ri (Japanese) (ri)
How long is one Ri in meters or kilometers?
The modern standardized Japanese Ri is defined as 36 chō. This precise length equates to:
- Exactly 43,200 / 11 meters
- Approximately 3927.27 meters
- Approximately 3.927 kilometers (km)
- Approximately 2.440 miles (mi)
- Exactly 12,960 shaku (traditional Japanese feet)
Remember that historical values of the Ri could differ significantly before standardization.
How does the Ri relate to other traditional Japanese length units?
The Ri sits at the top of a hierarchy of length units in the traditional Shakkanhō system:
- 1 Ri = 36 chō (町)
- 1 chō = 60 ken (間)
- 1 ken = 6 shaku (尺)
- 1 shaku = 10 sun (寸)
Understanding these relationships is key to converting historical measurements.
Is the Japanese Ri the same length as the Chinese Li or Korean Ri?
No, although they share the same origin and written character (里), their standardized lengths differ significantly. It is important not to confuse them:
- Japanese Ri (modern): Approximately 3927 meters
- Chinese Li (modern): Exactly 500 meters (defined for compatibility with the metric system)
- Korean Ri (modern): Approximately 393 meters (standardized differently based on the Korean cheok)
Historical values for all three units also varied greatly over time and by region.
Is the Ri an SI unit?
No, the Ri is not part of the International System of Units (SI). It is a traditional Japanese unit belonging to the historical Shakkanhō system. The official SI base unit for length is the meter (m), and the derived unit commonly used for long distances globally is the kilometer (km).
Is the Ri unit still used today in Japan?
The Ri is very rarely used for practical measurement in modern Japan. Its usage is almost entirely confined to:
- Historical contexts (studying Japanese history, interpreting old maps, etc.)
- Cultural references (found in classic literature, proverbs, traditional idioms)
- Geographical place names
- Figurative language (to express long distances metaphorically)
For all official, commercial, and everyday distance measurements, the kilometer (km) is the standard unit used in Japan.
Conversion Table: Nanometer to Ri (Japanese)
| Nanometer (nm) | Ri (Japanese) (ri) |
|---|---|
| 0.5 | 0 |
| 1 | 0 |
| 1.5 | 0 |
| 2 | 0 |
| 5 | 0 |
| 10 | 0 |
| 25 | 0 |
| 50 | 0 |
| 100 | 0 |
| 250 | 0 |
| 500 | 0 |
| 1,000 | 0 |
People Also Ask
How do I convert Nanometer to Ri (Japanese)?
To convert Nanometer to Ri (Japanese), enter the value in Nanometer in the calculator above. The conversion will happen automatically. Use our free online converter for instant and accurate results. You can also visit our length converter page to convert between other units in this category.
Learn more →What is the conversion factor from Nanometer to Ri (Japanese)?
The conversion factor depends on the specific relationship between Nanometer and Ri (Japanese). You can find the exact conversion formula and factor on this page. Our calculator handles all calculations automatically. See the conversion table above for common values.
Can I convert Ri (Japanese) back to Nanometer?
Yes! You can easily convert Ri (Japanese) back to Nanometer by using the swap button (⇌) in the calculator above, or by visiting our Ri (Japanese) to Nanometer converter page. You can also explore other length conversions on our category page.
Learn more →What are common uses for Nanometer and Ri (Japanese)?
Nanometer and Ri (Japanese) are both standard units used in length measurements. They are commonly used in various applications including engineering, construction, cooking, and scientific research. Browse our length converter for more conversion options.
For more length conversion questions, visit our FAQ page or explore our conversion guides.
Helpful Conversion Guides
Learn more about unit conversion with our comprehensive guides:
📚 How to Convert Units
Step-by-step guide to unit conversion with practical examples.
🔢 Conversion Formulas
Essential formulas for length and other conversions.
⚖️ Metric vs Imperial
Understand the differences between measurement systems.
⚠️ Common Mistakes
Learn about frequent errors and how to avoid them.
All Length Conversions
Other Length Units and Conversions
Explore other length units and their conversion options:
- Meter (m) • Nanometer to Meter
- Kilometer (km) • Nanometer to Kilometer
- Hectometer (hm) • Nanometer to Hectometer
- Decimeter (dm) • Nanometer to Decimeter
- Centimeter (cm) • Nanometer to Centimeter
- Millimeter (mm) • Nanometer to Millimeter
- Inch (in) • Nanometer to Inch
- Foot (ft) • Nanometer to Foot
- Yard (yd) • Nanometer to Yard
- Mile (mi) • Nanometer to Mile
Verified Against Authority Standards
All conversion formulas have been verified against international standards and authoritative sources to ensure maximum accuracy and reliability.
National Institute of Standards and Technology — Official US standards for length measurements
Bureau International des Poids et Mesures — International System of Units official documentation
Last verified: December 3, 2025