Dry ice colloquially means the solid form of carbon dioxide . It is commonly used for temporary refrigeration as CO 2 does not have a liquid state at normal atmospheric pressure and sublimes directly from the solid state to the gas state . It is used primarily as a cooling agent , but is also used in fog machines at theatres for dramatic effects. Its advantages include lower temperature than that of water ice and not leaving any residue (other than incidental frost from moisture in the atmosphere). It is useful for preserving frozen foods (such as ice cream) where mechanical cooling is unavailable.
54-564: [REDACTED] Look up snb in Wiktionary, the free dictionary. SNB may refer to: Beechcraft Model 18 aircraft, US Navy designation SNB-1 Kansan National Security Service (Uzbekistan) , transliteration of Cyrillic initials СНБ Santa Fe Depot (San Bernardino) , Amtrak station code SNB Sbor národní bezpečnosti , national police in Czechoslovakia 1945-1991 Service New Brunswick ,
108-492: A plastic bottle . Water is usually added to accelerate the sublimation of the dry ice. As the dry ice sublimes , pressure increases, causing the bottle to burst with a loud noise. The screw cap can be replaced with a rubber stopper to make a water rocket . The dry ice bomb device was featured on MythBusters , episode 57 Mentos and Soda , which first aired on August 9, 2006. It was also featured in an episode of Time Warp , as well as in an episode of Archer . Following
162-700: A car. In 2020, three people were killed at a party in Moscow after 25 kg of dry ice was dumped in a pool; carbon dioxide is heavier than air, and so can linger near the ground, just above water level. Dry ice is sometimes used to give a fog effect to cocktails . One bar patron who accidentally ingested pellets from a drink suffered severe burns to his esophagus , stomach , and duodenum , causing permanent problems with eating. Rapid sublimation could cause gas buildup that ruptures digestive organs or suffocation. Products that contain dry ice and prevent it from being accidentally ingested eliminate these risks while producing
216-576: A crown corporation in Canada Sunday Night Baseball , weekly ESPN broadcast Serie Nacional de Béisbol , Cuba's top-level baseball league Saudi National Bank (SNB), commercial bank in Saudi Arabia Swiss National Bank , the central bank of Switzerland Snake Bay Airport , IATA airport code "SNB" Topics referred to by the same term [REDACTED] This disambiguation page lists articles associated with
270-426: A danger of hypercapnia , dry ice should only be exposed to open air in a well-ventilated environment. For this reason, in the context of laboratory safety dry ice is assigned label precaution P403 : "Store in a well ventilated place." Industrial dry ice may contain contaminants that make it unsafe for direct contact with food. Tiny dry ice pellets used in dry ice blast cleaning do not contain oily residues. Dry ice
324-589: A further increase in MTOW to 10,286 lb (4,666 kg). The wing spar of the Model 18 was fabricated by welding an assembly of tubular steel. The configuration of the tubes in combination with drilled holes from aftermarket STC modifications on some of these aircraft have allowed the spar to become susceptible to corrosion and cracking while in service. This prompted the FAA to issue an Airworthiness Directive in 1975, mandating
378-405: A gas having a high concentration of carbon dioxide. Such gases can be a byproduct of another process, such as producing ammonia from nitrogen and natural gas , oil refinery activities or large-scale fermentation . Second, the carbon dioxide-rich gas is pressurized and refrigerated until it liquefies. Next, the pressure is reduced. When this occurs some liquid carbon dioxide vaporizes, causing
432-433: A gas makes dry ice an effective coolant , since it is colder than water ice and leaves no residue as it changes state. Its enthalpy of sublimation is 571 kJ/kg (25.2 kJ/mol, 136.5 calorie/g). Dry ice is non-polar , with a dipole moment of zero, so attractive intermolecular van der Waals forces operate. The composition results in low thermal and electrical conductivity . It is generally accepted that dry ice
486-538: A lengthened nose to accommodate the tricycle nosewheel , and the Model 18's twin tailfins were replaced by a single fin. Production got an early boost when Nationalist China paid the company US$ 750,000 for six M18R light bombers, but by the time of the U.S. entry into World War II , only 39 Model 18s had been sold, of which 29 were for civilian customers. Work began in earnest on a variant specifically for training United States Army Air Forces (USAAF) military pilots, bombardiers, and navigators. The effort resulted in
540-973: A rapid lowering of temperature of the remaining liquid. As a result, the extreme cold causes the liquid to solidify into a snow-like consistency. Finally, the snow-like solid carbon dioxide is compressed into small pellets or larger blocks of dry ice. Dry ice is typically produced in three standard forms: large blocks, small ( 1 ⁄ 2 or 5 ⁄ 8 in [13 or 16 mm] diameter) cylindrical pellets and tiny ( 1 ⁄ 8 inch [3.2 mm] diameter) cylindrical, high surface to volume pellets that float on oil or water and do not stick to skin because of their high radii of curvature. Tiny dry ice pellets are used primarily for dry ice blasting , quick freezing, fire fighting, oil solidifying and have been found to be safe for experimentation by middle school students wearing appropriate personal protective equipment such as gloves and safety glasses. A standard block weighing approximately 30 kg (66 lb) covered in
594-401: A taped paper wrapping is most common. These are commonly used in shipping, because they sublime relatively slowly due to a low ratio of surface area to volume. Pellets are around 1 cm (0.4 in) in diameter and can be bagged easily. This form is suited to small scale use, for example at grocery stores and laboratories where it is stored in a thickly insulated chest. Density of pellets
SECTION 10
#1732848292536648-417: A variety of engines and has had a number of airframe modifications to increase gross weight and speed. At least one aircraft was modified to a 600-hp (447-kW) Pratt & Whitney R-1340 powerplant configuration. With the added weight of about 200 lb (91 kg) per engine, the concept of a Model 18 fitted with R-1340 engines was deemed unsatisfactory due to the weakest structural area of the aircraft being
702-413: Is 60–70% of the density of blocks. Dry ice is also produced as a byproduct of cryogenic air separation , an industry primarily concerned with manufacturing extremely cold liquids such as liquid nitrogen and liquid oxygen . In this process, carbon dioxide liquefies or freezes at a far higher temperature compared to that needed to liquefy nitrogen and oxygen . The carbon dioxide must be removed during
756-543: Is also known) is a 6- to 11-seat, twin-engined, low-wing, tailwheel light aircraft manufactured by the Beech Aircraft Corporation of Wichita, Kansas . Continuously produced from 1937 to November 1969 (over 32 years, a world record at the time), over 9,000 were built, making it one of the world's most widely used light aircraft. Sold worldwide as a civilian executive, utility, cargo aircraft, and passenger airliner on tailwheels, nosewheels, skis, or floats, it
810-448: Is also useful as a cutting fluid . In laboratories , a slurry of dry ice in an organic solvent is a useful freezing mixture for cold chemical reactions and for condensing solvents in rotary evaporators . Dry ice and acetone forms a cold bath of −78 °C (−108 °F; 195 K), which can be used for instance to prevent thermal runaway in a Swern oxidation . The process of altering cloud precipitation can be done with
864-643: Is assigned a UN number , a code for hazardous substances: UN 1845 . Dry ice is not classified as a dangerous substance by the European Union , or as a hazardous material by the United States Department of Transportation for ground transportation. However, in the US, it is regulated as a dangerous good when shipped by air or water. International Air Transport Association (IATA) regulations require specific diamond-shaped black-and white labelling to be placed on
918-477: Is critical in the deployment of some vaccines, which require storage at ultra-cold temperatures along their supply line. Dry ice can be used to flash-freeze food or laboratory biological samples, carbonate beverages, make ice cream , solidify oil spills and stop ice sculptures and ice walls from melting. Dry ice can be used to arrest and prevent insect activity in closed containers of grains and grain products, as it displaces oxygen, but does not alter
972-642: Is done by dropping pellets into rodent tunnels in the ground and then sealing off the entrance, thus suffocating the animals as the dry ice sublimates. Tiny dry ice pellets can be used to fight fire by both cooling fuel and suffocating the fire by excluding oxygen. The extreme temperature of dry ice can cause viscoelastic materials to change to glass phase. Thus, it is useful for removing many types of pressure sensitive adhesives . Dry ice can be used for loosening asphalt floor tiles or car sound deadening material, making them easy to prise off, as well as freezing water in valveless pipes to enable repair. One of
1026-450: Is possible that flakes of dry ice precipitate. Observations from the Uranus flyby by Voyager 2 indicates that dry ice is present on the surface of its large moons Ariel , Umbriel and Titania . Scientists speculate that the magnetic field of Uranus contributes to the generation of CO 2 ice on the surfaces of its moons. Voyager 2 observations of Neptune's moon Triton suggested
1080-443: Is the sublimed CO 2 , thus making it a useful technique where residues from other blasting techniques are undesirable. Recently, blast cleaning has been introduced as a method of removing smoke damage from structures after fires. Dry ice is also useful for the de-gassing of flammable vapours from storage tanks — the sublimation of dry ice pellets inside an emptied and vented tank causes an outrush of CO 2 that carries with it
1134-603: Is used to cut off water flow to pipes to allow repairs to be made without shutting off water mains. Pressurised liquid CO 2 is forced into a jacket wrapped around a pipe, which in turn causes the water inside to freeze and block the pipe. When the repairs are done, the jacket is removed and the ice plug melts, allowing the flow to resume. This technique can be used on pipes up to 4 inches or 100 mm in diameter. Dry ice can be used as bait to trap mosquitoes , bedbugs , and other insects, due to their attraction to carbon dioxide. It can be used to exterminate rodents. This
SECTION 20
#17328482925361188-778: The pH of a solution when dissolved in water , forming carbonic acid (H 2 CO 3 ). At pressures below 5.13 atm and temperatures below −56.4 °C (216.8 K; −69.5 °F) (the triple point ), CO 2 changes from a solid to a gas with no intervening liquid form, through a process called sublimation . The opposite process is called deposition , where CO 2 changes from the gas to solid phase (dry ice). At atmospheric pressure, sublimation/deposition occurs at 194.7 K (−78.5 °C; −109.2 °F). The density of dry ice increases with decreasing temperature and ranges between about 1.55 and 1.7 g/cm (97 and 106 lb/cu ft) below 195 K (−78 °C; −109 °F). The low temperature and direct sublimation to
1242-875: The Army AT-7. Further development led to the AT-11 navigation trainer, C-45 military transport, and F-2 (the "F" standing for "Fotorecon", short for "photographic reconnaissance" ). The United States Navy first adopted the Beech 18 as the JRB-1, equivalent to the F-2, followed by the JRB-2 transport; the JRB was initially named the Voyager , but this name did not enter common use, and JRBs were generally called Expeditors like their USAAF counterparts. The first JRB-1 obtained by
1296-588: The Beechcraft Model 18 remains popular with air charter companies and small feeder airlines worldwide. The Beechcraft Model 18 family has been involved in the following notable accidents and incidents: Data from Jane's Fighting Aircraft of World War II. General characteristics Performance Aircraft of comparable role, configuration, and era Related lists Dry-ice Dry ice sublimes at 194.7 K (−78.5 °C; −109.2 °F) at Earth atmospheric pressure . This extreme cold makes
1350-460: The FAA and other national airworthiness authorities, including regular removal of the spar strap to allow the strap to be checked for cracks and corrosion and the spar to be X-rayed . In Australia, the airworthiness authority has placed a life limit on the airframe, beyond which aircraft are not allowed to fly. Unless otherwise noted, the engines fitted are Pratt & Whitney R-985 radials. C-45Ds delivered between 1951 and 1952 As of 2012 ,
1404-876: The JRB-6, the SNB-5, and SNB-5P. The Coast Guard retired its JRBs in 1956 and sold most of them as surplus in 1959, but one was retained by the United States Coast Guard Reserve until at least 1972. With the adoption of the 1962 United States Tri-Service aircraft designation system , the Navy's SNB-5 and SNB-5P became the TC-45J and RC-45J respectively, later becoming the UC-45J as their primary mission shifted from aircrew training to utility transport work. The C-45 flew in USAF service until 1963,
1458-571: The Mars flyby of the Mariner 4 spacecraft in 1966, scientists concluded that Mars' polar caps consist entirely of dry ice. However, findings made in 2003 by researchers at the California Institute of Technology have shown that Mars' polar caps are almost completely made of water ice, and that dry ice only forms a thin surface layer that thickens and thins seasonally. A phenomenon named dry ice storms
1512-591: The Navy between 1943 and 1947; they were primarily used as utility transports, with one aircraft later converted for aerial mapping, and another used for proficiency flying. After the war, the USAAF became the United States Air Force (USAF), and the USAF Strategic Air Command had Model 18 variants (AT-11 Kansans, C-45 Expeditors, F-2 Expeditors, and UC-45 Expeditors) from 1946 until 1951. In 1950,
1566-537: The Navy still had around 1,200 JRB and SNB aircraft in inventory. From 1951 to 1955, the USAF had many of its aircraft remanufactured with new fuselages, wing center sections, and undercarriages to take advantage of the improvements to the civil models since the end of World War II. Eventually, 900 aircraft were remanufactured to be similar to the then-current Model D18S and given new designations, constructor's numbers, and Air Force serial numbers. The USN had many of its surviving aircraft remanufactured as well, resulting in
1620-709: The Navy, bureau number (BuNo) 09771 , was converted from the last civil Model 18 built before production was earmarked solely for the military for the duration of the war. The Navy subsequently obtained more Model 18s as the JRB-3 (C-45B), JRB-4 (UC-45F), SNB-1 Kansan (AT-11), SNB-2 (AT-7), and SNB-2C (AT-7C). Existing naval Twin Beeches were subsequently modified into the SNB-2H air ambulance, SNB-2P reconnaissance trainer, and SNB-3Q electronic countermeasures trainer. The United States Coast Guard acquired seven JRB-4 and JRB-5 aircraft from
1674-569: The USN retired its last UC-45J in 1972, while the U.S. Army flew its C-45s until 1976. In later years, the military called these aircraft "bug smashers" in reference to their extensive use supplying mandatory flight hours for desk-bound aviators in the Pentagon. Beech 18s were used extensively by Air America during the Vietnam War ; initially more-or-less standard ex-military C-45 examples were used, but then
SNB - Misplaced Pages Continue
1728-648: The airline had 12 aircraft modified by Conrad Conversions in 1963 and 1964 to increase performance and load-carrying capacity. The modified aircraft were known as Conrad Ten-Twos, as the maximum takeoff weight (MTOW) was increased to 10,200 lb (4,600 kg). The increase was achieved by several airframe modifications, including increased horizontal stabilizer angle-of-incidence, redesigned undercarriage doors, and aerodynamically improved wingtips. Air America then had Volpar convert 14 aircraft to turboprop power, fitted with Garrett AiResearch TPE-331 engines; modified aircraft were called Volpar Turbo Beeches, and also had
1782-489: The early postwar era, the Beech 18 was the pre-eminent "business aircraft" and "feeder airliner". Besides carrying passengers, its civilian uses have included aerial spraying , sterile insect release , fish stocking , dry-ice cloud seeding , aerial firefighting , air-mail delivery, ambulance service, numerous movie productions, skydiving , freight, weapon- and drug- smuggling , engine testbed, skywriting , banner towing , and stunt aircraft. Many are privately owned, around
1836-605: The engine mounts. Nearly every airframe component has been modified. In 1955, deliveries of the Model E18S commenced; the E18S featured a fuselage that was extended 6 in (150 mm) higher for more headroom in the passenger cabin. All later Beech 18s (sometimes called Super 18s) featured this taller fuselage , and some earlier models (including one AT-11) have been modified to this larger fuselage. The Model H18, introduced in 1963, featured optional tricycle undercarriage . Unusually,
1890-531: The first to make dry ice successful as an industry . In 1925, this solid form of CO 2 was trademarked by the DryIce Corporation of America as "Dry ice", leading to its common name. That same year the DryIce Co. sold the substance commercially for the first time, marketing it for refrigeration purposes. Dry ice is easily manufactured. The most common industrial method of manufacturing dry ice starts with
1944-459: The fitting of a spar strap to some Model 18s. This led, in turn, to the retirement of a large number of STC-modified Model 18s when owners determined the aircraft were worth less than the cost of the modifications. The corrosion on unmodified spars was not a problem; it occurred due to the additional exposed surface area created through the STC hole-drilling process. Further requirements have been mandated by
1998-414: The flammable vapours. The removal and fitting of cylinder liners in large engines requires the use of dry ice to chill and thus shrink the liner so that it freely slides into the engine block. When the liner then warms up, it expands, and the resulting interference fit holds it tightly in place. Similar procedures may be used in fabricating mechanical assemblies with a high resultant strength, replacing
2052-564: The ground. Dry ice is useful in theatre productions that require dense fog effects. The fog originates from the bulk water into which the dry ice is placed, and not from atmospheric water vapor (as is commonly assumed). It is occasionally used to freeze and remove warts . However, liquid nitrogen performs better in this role, as it is colder, thereby requiring less time to act, and needs less pressure to store. Dry ice has fewer problems with storage, since it can be generated from compressed carbon dioxide gas as needed. In plumbing , dry ice
2106-484: The largest mechanical uses of dry ice is blast cleaning . Dry ice pellets are shot from a nozzle with compressed air , combining the power of the speed of the pellets with the action of the sublimation. This can remove residues from industrial equipment. Examples of materials removed include ink, glue, oil, paint, mold and rubber. Dry ice blasting can replace sandblasting, steam blasting, water blasting or solvent blasting. The primary environmental residue of dry ice blasting
2160-436: The need for pins, keys or welds. Dry ice has found its application in construction for freezing soil , serving as an effective alternative to liquid nitrogen . This method reduces the soil temperature to approximately -70 to -74 °C, rapidly freezing the groundwater. As a result, the soil's strength and impermeability significantly increase, which is essential for the safe execution of underground construction projects. It
2214-531: The package. The package must have adequate ventilation so that it will not rupture from pressure in the event that the Dry Ice begins to sublime in the packaging. The Federal Aviation Administration in the US allows airline passengers to carry up to 2.5 kg (5.5 lb) per person either as checked baggage or carry-on baggage, when used to refrigerate perishables. At least one person has been killed by carbon dioxide gas subliming off dry ice in coolers placed in
SNB - Misplaced Pages Continue
2268-465: The presence of dry ice on the surface, though followup observations indicate that the carbon ices on the surface are carbon monoxide but that the moon's crust is composed of a significant quantity of dry ice. Prolonged exposure to dry ice can cause severe skin damage through frostbite , and the fog produced may also hinder attempts to withdraw from contact in a safe manner. Because it sublimes into large quantities of carbon dioxide gas, which could pose
2322-449: The process to prevent dry ice from fouling the equipment, and once separated can be processed into commercial dry ice in a manner similar to that described above. The most common use of dry ice is to preserve food, using non-cyclic refrigeration . It is frequently used to package items that must remain cold or frozen, such as ice cream or biological samples, in the absence of availability or practicality of mechanical cooling . Dry ice
2376-455: The solid dangerous to handle without protection from frostbite injury. While generally not very toxic, the outgassing from it can cause hypercapnia (abnormally elevated carbon dioxide levels in the blood) due to buildup in confined locations. Dry ice is the solid form of carbon dioxide (CO 2 ), a molecule consisting of a single carbon atom bonded to two oxygen atoms . Dry ice is colorless, odorless, and non-flammable, and can lower
2430-459: The taste or quality of foods. For the same reason, it can prevent or retard food oils and fats from becoming rancid . When dry ice is placed in water, sublimation is accelerated, and low-sinking, dense clouds of smoke-like fog are created. This is used in fog machines , at theatres , haunted house attractions , and nightclubs for dramatic effects. Unlike most artificial fog machines , in which fog rises like smoke, fog from dry ice hovers near
2484-496: The title SNB . If an internal link led you here, you may wish to change the link to point directly to the intended article. Retrieved from " https://en.wikipedia.org/w/index.php?title=SNB&oldid=1145595821 " Category : Disambiguation pages Hidden categories: Short description is different from Wikidata All article disambiguation pages All disambiguation pages Beechcraft Model 18 The Beechcraft Model 18 (or " Twin Beech ", as it
2538-448: The undercarriage was developed for earlier-model aircraft under an STC by Volpar , and installed in H18s at the factory during manufacture. A total of 109 H18s was built with tricycle undercarriage, and another 240 earlier-model aircraft were modified with this. Construction of the Beechcraft Model 18 ended in 1970 with a final Model H18 going to Miyazaki Aviation College, Japan . Through
2592-414: The use of dry ice. It was widely used in experiments in the US in the 1950s and early 1960s before it was replaced by silver iodide . Dry ice has the advantage of being relatively cheap and completely non-toxic. Its main drawback is the need to be delivered directly into the supercooled region of clouds being seeded. A "dry ice bomb" is a balloon-like device using dry ice in a sealed container such as
2646-664: The world, with 240 in the U.S. still on the FAA Aircraft Registry in August 2017. By the late 1930s, Beechcraft management speculated that a demand would exist for a new design dubbed the Model 18 , which would have a military application, and increased the main production facilities. The design was mainly conventional for the time, including twin radial engines , all-metal semimonocoque construction with fabric-covered control surfaces, and tailwheel undercarriage . Less conventional
2700-470: The years, 32 variations of the basic design had flown, over 200 improvement modification kits were developed, and almost 8,000 aircraft were built. In one case, the aircraft was modified to a triple tail, trigear, humpbacked configuration and appeared similar to a miniature Lockheed Constellation . Another distinctive conversion was carried out by Pacific Airmotive as the PacAero Tradewind. This featured
2754-577: Was also used as a military aircraft . During and after World War II , over 4,500 Beech 18s were used in military service—as light transport, light bomber (for China), aircrew trainer (for bombing, navigation, and gunnery), photo-reconnaissance , and "mother ship" for target drones —including United States Army Air Forces (USAAF) C-45 Expeditor , AT-7 Navigator , and AT-11 Kansan ; and United States Navy (USN) UC-45J Navigator , SNB-1 Kansan , and others. In World War II , over 90% of USAAF bombardiers and navigators trained in these aircraft. In
SECTION 50
#17328482925362808-458: Was first observed in 1835 by French inventor Adrien-Jean-Pierre Thilorier (1790–1844), who published the first account of the substance. In his experiments, he noted that when opening the lid of a large cylinder containing liquid carbon dioxide , most of the liquid carbon dioxide quickly evaporated. This left only solid dry ice in the container. In 1924, Thomas B. Slate applied for a US patent to sell dry ice commercially. Subsequently, he became
2862-485: Was proposed to occur over the polar regions of Mars. They are comparable to Earth's thunderstorms, with crystalline CO 2 taking the place of water in the clouds. Dry ice is also proposed as a mechanism for the geysers on Mars . In 2012, the European Space Agency 's Venus Express probe detected a cold layer in the atmosphere of Venus where temperatures are close to the triple point of carbon dioxide and it
2916-452: Was the twin-tailfin configuration. The Model 18 can be mistaken for the larger Lockheed Electra series of airliners, which closely resemble it. Early production aircraft were powered either by two 330-hp (250-kW) Jacobs L-6s or 350-hp (260-kW) Wright R-760Es. The 450-hp (336-kW) Pratt & Whitney R-985 became the definitive engine from the prewar C18S onwards. The Beech 18 prototype first flew on 15 January 1937. The aircraft has used
#535464