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145-666: Castor is a family of solid-fuel rocket stages and boosters built by Thiokol (now Northrop Grumman ) and used on a variety of launch vehicles . They were initially developed as the second-stage motor of the Scout rocket . The design was based on the MGM-29 Sergeant , a surface-to-surface missile developed for the United States Army at the Jet Propulsion Laboratory . Instead of using

290-688: A D6AC steel case and PBAN binder like the Space Shuttle SRB, these will use the technology derived from the GEM motors which have carbon composite cases and HTPB binder. The carbon composite design eliminates the factory joint common on all Space Shuttle SRBs. Solid-fuel rocket A solid-propellant rocket or solid rocket is a rocket with a rocket engine that uses solid propellants ( fuel / oxidizer ). The earliest rockets were solid-fuel rockets powered by gunpowder . The inception of gunpowder rockets in warfare can be credited to

435-411: A bureaucratic system that favored the land-holding class able to afford the best education. One of the greatest literary critics of this was the official and famous poet Su Shi . Yet Su was a product of his times, as the identity, habits, and attitudes of the scholar-official had become less aristocratic and more bureaucratic with the transition of the periods from Tang to Song. At the beginning of

580-413: A casing, nozzle , grain ( propellant charge ), and igniter . The solid grain mass burns in a predictable fashion to produce exhaust gases, the flow of which is described by Taylor–Culick flow . The nozzle dimensions are calculated to maintain a design chamber pressure, while producing thrust from the exhaust gases. Once ignited, a simple solid rocket motor cannot be shut off, as it contains all

725-618: A compass, first recorded description of the pound lock , and improved designs of astronomical clocks . Economically, the Song dynasty was unparalleled with a gross domestic product three times larger than that of Europe during the 12th century. China's population doubled in size between the 10th and 11th centuries. This growth was made possible by expanded rice cultivation , use of early-ripening rice from Southeast and South Asia, and production of widespread food surpluses. The Northern Song census recorded 20 million households, double that of

870-487: A control moment. For example, the Titan III C solid boosters injected nitrogen tetroxide for LITV; the tanks can be seen on the sides of the rocket between the main center stage and the boosters. An early Minuteman first stage used a single motor with four gimballed nozzles to provide pitch, yaw, and roll control. A typical, well-designed ammonium perchlorate composite propellant (APCP) first-stage motor may have

1015-436: A departure from the earlier Tang dynasty (618–907), when the government strictly regulated commercial markets and local affairs; now the government withdrew heavily from regulating commerce and relied upon a mass of local gentry to perform necessary duties in their communities. The gentry distinguished themselves in society through their intellectual and antiquarian pursuits, while the homes of prominent landholders attracted

1160-657: A great effect on people's lives, beliefs, and daily activities, and Chinese literature on spirituality was popular. The major deities of Daoism and Buddhism , ancestral spirits , and the many deities of Chinese folk religion were worshipped with sacrificial offerings. Tansen Sen asserts that more Buddhist monks from India traveled to China during the Song than in the previous Tang dynasty (618–907). With many ethnic foreigners travelling to China to conduct trade or live permanently, there came many foreign religions; religious minorities in China included Middle Eastern Muslims ,

1305-412: A high level of suspicion by the judge. Due to costly court expenses and immediate jailing of those accused of criminal offenses, people in the Song preferred to settle disputes and quarrels privately, without the court's interference. Shen Kuo's Dream Pool Essays argued against traditional Chinese beliefs in anatomy (such as his argument for two throat valves instead of three); this perhaps spurred

1450-541: A high-energy (yet unstable) monopropellant and the other acts as a lower-energy stabilizing (and gelling) monopropellant. In typical circumstances, nitroglycerin is dissolved in a nitrocellulose gel and solidified with additives. DB propellants are implemented in applications where minimal smoke is required yet a medium-high I sp of roughly 235 s (2.30 km/s) is required. The addition of metal fuels (such as aluminium ) can increase performance to around 250 s (2.5 km/s), though metal oxide nucleation in

1595-673: A literary flourishing in the Song period, which saw the publication of several major classical koan collections which remain influential in Zen philosophy and practice to the present day. A true revival of Buddhism in Chinese society would not occur until the Mongol rule of the Yuan dynasty, with Kublai Khan's sponsorship of Tibetan Buddhism and Drogön Chögyal Phagpa as the leading lama . The Christian sect of Nestorianism , which had entered China in

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1740-564: A long history as the final boost stage for satellites due to their simplicity, reliability, compactness and reasonably high mass fraction . A spin-stabilized solid rocket motor is sometimes added when extra velocity is required, such as for a mission to a comet or the outer solar system, because a spinner does not require a guidance system (on the newly added stage). Thiokol's extensive family of mostly titanium-cased Star space motors has been widely used, especially on Delta launch vehicles and as spin-stabilized upper stages to launch satellites from

1885-499: A loss in motor performance. Polyurethane-bound aluminium-APCP solid fuel was used in the submarine-launched Polaris missiles . APCP used in the space shuttle Solid Rocket Boosters consisted of ammonium perchlorate (oxidizer, 69.6% by weight), aluminium (fuel, 16%), iron oxide (a catalyst, 0.4%), polybutadiene acrylonitrile (PBAN) polymer (a non-urethane rubber binder that held the mixture together and acted as secondary fuel, 12.04%), and an epoxy curing agent (1.96%). It developed

2030-461: A lower social tier than men according to Confucian ethics, they enjoyed many social and legal privileges and wielded considerable power at home and in their own small businesses. As Song society became more and more prosperous and parents on the bride's side of the family provided larger dowries for her marriage, women naturally gained many new legal rights in ownership of property. Under certain circumstances, an unmarried daughter without brothers, or

2175-503: A million a century later. This economic power also heavily influenced foreign economies abroad. In 1120 alone, the Song government collected 18,000,000 ounces (510,000 kg) of silver in taxes. The Moroccan geographer al-Idrisi wrote in 1154 of the prowess of Chinese merchant ships in the Indian Ocean and of their annual voyages that brought iron, swords, silk, velvet, porcelain, and various textiles to places such as Aden ( Yemen ),

2320-600: A new organization of classic texts that established the doctrine of Neo-Confucianism . Although civil service examinations had existed since the Sui dynasty , they became much more prominent in the Song period. Officials gaining power through imperial examination led to a shift from a military-aristocratic elite to a scholar-bureaucratic elite. After usurping the throne of the Later Zhou dynasty , Emperor Taizu of Song ( r.  960–976 ) spent sixteen years conquering

2465-456: A philosophical point. Although an early form of the local geographic gazetteer existed in China since the 1st century, the matured form known as "treatise on a place", or fangzhi , replaced the old "map guide", or transl.  zho  – transl.  tujing , during the Song dynasty. The imperial courts of the emperor's palace were filled with his entourage of court painters, calligraphers, poets, and storytellers. Emperor Huizong

2610-594: A propellant mass fraction of 92.23% while the 14,000-kilogram (31,000 lb) Castor 30 upper stage developed for Orbital Science's Taurus II COTS (Commercial Off The Shelf) (International Space Station resupply) launch vehicle has a 91.3% propellant fraction with 2.9% graphite epoxy motor casing, 2.4% nozzle, igniter and thrust vector actuator, and 3.4% non-motor hardware including such things as payload mount, interstage adapter, cable raceway, instrumentation, etc. Castor 120 and Castor 30 are 2.36 and 2.34 meters (93 and 92 in) in diameter, respectively, and serve as stages on

2755-458: A raid on Guangxi , the Song commander Guo Kui (1022–1088) penetrated as far as Thăng Long (modern Hanoi ). Heavy losses on both sides prompted the Vietnamese commander Thường Kiệt (1019–1105) to make peace overtures, allowing both sides to withdraw from the war effort; captured territories held by both Song and Vietnamese were mutually exchanged in 1082, along with prisoners of war. During

2900-895: A range of 5,500 metres (3.4 mi). By the end of World War II total production of rocket launchers reached about 10,000. with 12 million rockets of the RS type produced for the Soviet armed forces. In the United States modern castable composite solid rocket motors were invented by the American aerospace engineer Jack Parsons at Caltech in 1942 when he replaced double base propellant with roofing asphalt and potassium perchlorate . This made possible slow-burning rocket motors of adequate size and with sufficient shelf-life for jet-assisted take off applications. Charles Bartley , employed at JPL (Caltech), substituted curable synthetic rubber for

3045-492: A simple, solid-propellant rocket tube that was filled with gunpowder. One open end allowed the gas to escape and was attached to a long stick that acted as a guidance system for flight direction control. The first rockets with tubes of cast iron were used by the Kingdom of Mysore under Hyder Ali and Tipu Sultan in the 1750s. These rockets had a reach of targets up to a mile and a half away. These were extremely effective in

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3190-414: A single-piece nozzle or 304 s (2.98 km/s) with a high-area-ratio telescoping nozzle. Aluminium is used as fuel because it has a reasonable specific energy density, a high volumetric energy density, and is difficult to ignite accidentally. Composite propellants are cast, and retain their shape after the rubber binder, such as Hydroxyl-terminated polybutadiene (HTPB), cross-links (solidifies) with

3335-943: A small charge that is set off when the propellant is exhausted after a time delay. This charge can be used to trigger a camera , or deploy a parachute . Without this charge and delay, the motor may ignite a second stage (black powder only). In mid- and high-power rocketry , commercially made APCP motors are widely used. They can be designed as either single-use or reloadables. These motors are available in impulse ranges from "A" (1.26 Ns– 2.50 Ns) to "O" (20.48 kNs – 40.96 kNs), from several manufacturers. They are manufactured in standardized diameters and varying lengths depending on required impulse. Standard motor diameters are 13, 18, 24, 29, 38, 54, 75, 98, and 150 millimeters. Different propellant formulations are available to produce different thrust profiles, as well as special effects such as colored flames, smoke trails, or large quantities of sparks (produced by adding titanium sponge to

3480-424: A small scale during the Sui and Tang dynasties, but by the Song period, it became virtually the only means for drafting officials into the government. The advent of widespread printing helped to widely circulate Confucian teachings and to educate more and more eligible candidates for the exams. This can be seen in the number of exam takers for the low-level prefectural exams rising from 30,000 annual candidates in

3625-406: A specific impulse of 242 seconds (2.37 km/s) at sea level or 268 seconds (2.63 km/s) in a vacuum. The 2005-2009 Constellation Program was to use a similar PBAN-bound APCP. In 2009, a group succeeded in creating a propellant of water and nanoaluminium ( ALICE ). Typical HEC propellants start with a standard composite propellant mixture (such as APCP) and add a high-energy explosive to

3770-466: A sugar fuel (typically dextrose , sorbitol , or sucrose ) that are cast into shape by gently melting the propellant constituents together and pouring or packing the amorphous colloid into a mold. Candy propellants generate a low-medium specific impulse of roughly 130 s (1.3 km/s) and, thus, are used primarily by amateur and experimental rocketeers. DB propellants are composed of two monopropellant fuel components where one typically acts as

3915-541: A surviving mother without sons, could inherit one-half of her father's share of undivided family property. There were many notable and well-educated women, and it was a common practice for women to educate their sons during their earliest youth. The mother of the scientist, general, diplomat, and statesman Shen Kuo taught him essentials of military strategy. There were also exceptional women writers and poets, such as Li Qingzhao (1084–1151), who became famous even in her lifetime. Religion in China during this period had

4060-588: A tribute to Song. Champa rice was drought-resistant and able to grow fast enough to offer two harvests a year instead of one. Song restaurant and tavern menus are recorded. They list entrees for feasts, banquets, festivals, and carnivals. They reveal a diverse and lavish diet for those of the upper class. They could choose from a wide variety of meats and seafood, including shrimp, geese, duck, mussel, shellfish, fallow deer , hare, partridge, pheasant, francolin, quail, fox, badger, clam, crab, and many others. Dairy products were rare in Chinese cuisine at this time. Beef

4205-684: A vacuum specific impulse ( I sp ) as high as 285.6 seconds (2.801 km/s) (Titan IVB SRMU). This compares to 339.3 s (3.327 km/s) for RP1/LOX (RD-180) and 452.3 s (4.436 km/s) for LH 2 /LOX (Block II RS-25 ) bipropellant engines. Upper stage specific impulses are somewhat greater: as much as 303.8 s (2.979 km/s) for APCP (Orbus 6E), 359 s (3.52 km/s) for RP1/LOX (RD-0124) and 465.5 s (4.565 km/s) for LH 2 /LOX (RL10B-2). Propellant fractions are usually somewhat higher for (non-segmented) solid propellant first stages than for upper stages. The 53,000-kilogram (117,000 lb) Castor 120 first stage has

4350-515: A variety of courtiers , including artisans, artists, educational tutors, and entertainers. Despite the disdain for trade, commerce, and the merchant class exhibited by the highly cultured and elite exam-drafted scholar-officials, commercialism played a prominent role in Song culture and society. A scholar-official would be frowned upon by his peers if he pursued means of profiteering outside of his official salary; however, this did not stop many scholar-officials from managing business relations through

4495-564: A very primitive form of solid-propellant rocket. Illustrations and descriptions in the 14th century Chinese military treatise Huolongjing by the Ming dynasty military writer and philosopher Jiao Yu confirm that the Chinese in 1232 used proto solid propellant rockets then known as " fire arrows " to drive back the Mongols during the Mongol siege of Kaifeng . Each arrow took a primitive form of

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4640-492: Is another pressed propellant that does not find any practical application outside specialized amateur rocketry circles due to its poor performance (as most ZS burns outside the combustion chamber) and fast linear burn rates on the order of 2 m/s. ZS is most often employed as a novelty propellant as the rocket accelerates extremely quickly leaving a spectacular large orange fireball behind it. In general, rocket candy propellants are an oxidizer (typically potassium nitrate) and

4785-552: Is cheap and fairly easy to produce. The fuel grain is typically a mixture of pressed fine powder (into a solid, hard slug), with a burn rate that is highly dependent upon exact composition and operating conditions. The specific impulse of black powder is low, around 80 s (0.78 km/s). The grain is sensitive to fracture and, therefore, catastrophic failure. Black powder does not typically find use in motors above 40 newtons (9.0 pounds-force) thrust. Composed of powdered zinc metal and powdered sulfur (oxidizer), ZS or "micrograin"

4930-408: Is equal to the volumetric rate times the fuel density ρ {\displaystyle \rho } : Several geometric configurations are often used depending on the application and desired thrust curve : The casing may be constructed from a range of materials. Cardboard is used for small black powder model motors, whereas aluminium is used for larger composite-fuel hobby motors. Steel

5075-428: Is non-polluting: acid-free, solid particulates-free, and lead-free. It is also smokeless and has only a faint shock diamond pattern that is visible in the otherwise transparent exhaust. Without the bright flame and dense smoke trail produced by the burning of aluminized propellants, these smokeless propellants all but eliminate the risk of giving away the positions from which the missiles are fired. The new CL-20 propellant

5220-411: Is shock-insensitive (hazard class 1.3) as opposed to current HMX smokeless propellants which are highly detonable (hazard class 1.1). CL-20 is considered a major breakthrough in solid rocket propellant technology but has yet to see widespread use because costs remain high. Electric solid propellants (ESPs) are a family of high performance plastisol solid propellants that can be ignited and throttled by

5365-434: Is to achieve mid-course exo-atmospheric ABM capability from missiles small enough to fit in existing ship-based below-deck vertical launch tubes and air-mobile truck-mounted launch tubes. CL-20 propellant compliant with Congress' 2004 insensitive munitions (IM) law has been demonstrated and may, as its cost comes down, be suitable for use in commercial launch vehicles, with a very significant increase in performance compared with

5510-516: The Eighteen Songs of a Nomad Flute from the life story of Cai Wenji (b. 177). This art project was a diplomatic gesture to the Jin dynasty while he negotiated for the release of his mother from Jurchen captivity in the north. In philosophy, Chinese Buddhism had waned in influence but it retained its hold on the arts and on the charities of monasteries. Buddhism had a profound influence upon

5655-664: The Battle of Khalkhin Gol . In June 1938, the RNII began developing a multiple rocket launcher based on the RS-132 rocket. In August 1939, the completed product was the BM-13 / Katyusha rocket launcher . Towards the end of 1938 the first significant large scale testing of the rocket launchers took place, 233 rockets of various types were used. A salvo of rockets could completely straddle a target at

5800-860: The Fatimid Caliphate of Egypt, Srivijaya , the Kara-Khanid Khanate in Central Asia , the Goryeo Kingdom in Korea, and other countries that were also trade partners with Japan . Chinese records even mention an embassy from the ruler of "Fu lin" (拂菻, i.e. the Byzantine Empire ), Michael VII Doukas , and its arrival in 1081. However, China's closest neighbouring states had the greatest impact on its domestic and foreign policy. From its inception under Taizu,

5945-598: The Han and Tang dynasties. It is estimated that the Northern Song had a population of 90 million people, and 200 million by the time of the Ming dynasty . This dramatic increase of population fomented an economic revolution in pre-modern China . The expansion of the population, growth of cities, and emergence of a national economy led to the gradual withdrawal of the central government from direct intervention in

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6090-750: The Indus River , and the Euphrates . Foreigners, in turn, affected the Chinese economy. For example, many West and Central Asian Muslims went to China to trade, becoming a preeminent force in the import and export industry, while some were even appointed as officers supervising economic affairs. Sea trade with the South-west Pacific, the Hindu world, the Islamic world, and East Africa brought merchants great fortune and spurred an enormous growth in

6235-916: The Kaifeng Jews , and Persian Manichaeans . The populace engaged in a vibrant social and domestic life, enjoying such public festivals as the Lantern Festival and the Qingming Festival . There were entertainment quarters in the cities providing a constant array of amusements. There were puppeteers, acrobats, theatre actors, sword swallowers, snake charmers, storytellers , singers and musicians, prostitutes, and places to relax, including tea houses, restaurants, and organized banquets. People attended social clubs in large numbers; there were tea clubs, exotic food clubs, antiquarian and art collectors' clubs, horse-loving clubs, poetry clubs, and music clubs. Like regional cooking and cuisines in

6380-672: The Mongol Empire , died in 1259 while besieging the mountain castle Diaoyucheng in Chongqing . His younger brother Kublai Khan was proclaimed the new Great Khan and in 1271 founded the Yuan dynasty. After two decades of sporadic warfare, Kublai Khan's armies conquered the Song dynasty in 1279 after defeating the Southern Song in the Battle of Yamen , and reunited China under the Yuan dynasty. Technology , science, philosophy, mathematics, and engineering flourished during

6525-487: The Pearl River Delta in 1279, the Yuan army, led by the general Zhang Hongfan , finally crushed the Song resistance. The last remaining ruler, the 13-year-old emperor Zhao Bing , committed suicide, along with Prime Minister Lu Xiufu and 1300 members of the royal clan. On Kublai's orders, carried out by his commander Bayan, the rest of the former imperial family of Song were unharmed; the deposed Emperor Gong

6670-668: The Reactive Scientific Research Institute (RNII) with the development of the RS-82 and RS-132 rockets , including designing several variations for ground-to-air, ground-to-ground, air-to-ground and air-to-air combat. The earliest known use by the Soviet Air Force of aircraft-launched unguided anti-aircraft rockets in combat against heavier-than-air aircraft took place in August 1939 , during

6815-788: The Second Anglo-Mysore War that ended in a humiliating defeat for the British East India Company . Word of the success of the Mysore rockets against the British triggered research in England, France, Ireland and elsewhere. When the British finally conquered the fort of Srirangapatana in 1799, hundreds of rockets were shipped off to the Royal Arsenal near London to be reverse-engineered. This led to

6960-628: The Yangtze to establish a new capital at Lin'an (modern Hangzhou). The Jurchen conquest of North China and shift of capitals from Kaifeng to Lin'an was the dividing line between the Northern and Southern Song dynasties. After their fall to the Jin, the Song lost control of North China. Now occupying what has been traditionally known as "China Proper", the Jin regarded themselves the rightful rulers of China. The Jin later chose earth as their dynastic element and yellow as their royal color. According to

7105-500: The fuel and oxidizer mass. Grain geometry and chemistry are then chosen to satisfy the required motor characteristics. The following are chosen or solved simultaneously. The results are exact dimensions for grain, nozzle, and case geometries: The grain may or may not be bonded to the casing. Case-bonded motors are more difficult to design, since the deformation of the case and the grain under flight must be compatible. Common modes of failure in solid rocket motors include fracture of

7250-411: The go and xiangqi board games. During this period greater emphasis was laid upon the civil service system of recruiting officials; this was based upon degrees acquired through competitive examinations , in an effort to select the most capable individuals for governance. Selecting men for office through proven merit was an ancient idea in China . The civil service system became institutionalized on

7395-417: The shipbuilding industry of Song-era Fujian . However, there was risk involved in such long overseas ventures. In order to reduce the risk of losing money on maritime trade missions abroad, wrote historians Ebrey, Walthall, and Palais: [Song era] investors usually divided their investment among many ships, and each ship had many investors behind it. One observer thought eagerness to invest in overseas trade

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7540-461: The universal history text of the Zizhi Tongjian , compiled into 1000 volumes of 9.4 million written Chinese characters . The genre of Chinese travel literature also became popular with the writings of the geographer Fan Chengda (1126–1193) and Su Shi, the latter of whom wrote the 'daytrip essay' known as Record of Stone Bell Mountain that used persuasive writing to argue for

7685-473: The 11th century, political rivalries divided members of the court due to the ministers' differing approaches, opinions, and policies regarding the handling of the Song's complex society and thriving economy. The idealist Chancellor , Fan Zhongyan (989–1052), was the first to receive a heated political backlash when he attempted to institute the Qingli Reforms , which included measures such as improving

7830-405: The 11th-century innovation of the use of coal instead of charcoal in blast furnaces for smelting cast iron . Much of this iron was reserved for military use in crafting weapons and armouring troops, but some was used to fashion the many iron products needed to fill the demands of the growing domestic market. The iron trade within China was advanced by the construction of new canals, facilitating

7975-582: The 2010s include the European Ariane 5 , US Atlas V and Space Shuttle , and Japan's H-II . The largest solid rocket motors ever built were Aerojet's three 6.60-meter (260 in) monolithic solid motors cast in Florida. Motors 260 SL-1 and SL-2 were 6.63 meters (261 in) in diameter, 24.59 meters (80 ft 8 in) long, weighed 842,900 kilograms (1,858,300 lb), and had a maximum thrust of 16 MN (3,500,000 lbf). Burn duration

8120-667: The Athena IC and IIC commercial launch vehicles. A four-stage Athena II using Castor 120s as both first and second stages became the first commercially developed launch vehicle to launch a lunar probe ( Lunar Prospector ) in 1998. Solid rockets can provide high thrust for relatively low cost. For this reason, solids have been used as initial stages in rockets (for example the Space Shuttle ), while reserving high specific impulse engines, especially less massive hydrogen-fueled engines, for higher stages. In addition, solid rockets have

8265-618: The Confucian classics of the Four Books as an introductory corpus to Confucian learning formed the basis of the Neo-Confucian doctrine. By the year 1241, under the sponsorship of Emperor Lizong , Zhu Xi's Four Books and his commentary on them became standard requirements of study for students attempting to pass the civil service examinations. The neighbouring countries of Japan and Korea also adopted Zhu Xi's teaching, known as

8410-423: The Jin dynasty. It had able military officers such as Yue Fei and Han Shizhong . The government sponsored massive shipbuilding and harbor improvement projects, and the construction of beacons and seaport warehouses to support maritime trade abroad, including at the major international seaports , such as Quanzhou , Guangzhou , and Xiamen , that were sustaining China's commerce. To protect and support

8555-580: The Liao forces, who engaged in aggressive yearly campaigns into Northern Song territory until 1005, when the signing of the Shanyuan Treaty ended these northern border clashes. The Song were forced to provide tribute to the Khitans, although this did little damage to the Song economy since the Khitans were economically dependent upon importing massive amounts of goods from the Song. More significantly,

8700-441: The Mongols as vassals ; when the Jin suddenly moved their capital city from Beijing to Kaifeng, the Mongols saw this as a revolt. Under the leadership of Ögedei Khan (r.1229–1241), both the Jin dynasty and Western Xia dynasty were conquered by Mongol forces in 1233/34. The Mongols were allied with the Song, but this alliance was broken when the Song recaptured the former imperial capitals of Kaifeng, Luoyang , and Chang'an at

8845-519: The New Policies and pursued political opponents, tolerated corruption and encouraged Emperor Huizong (1100–1126) to neglect his duties to focus on artistic pursuits. Later, a peasant rebellion broke out in Zhejiang and Fujian, headed by Fang La in 1120. The rebellion may have been caused by an increasing tax burden, the concentration of landownership and oppressive government measures. While

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8990-591: The Northern Song ( 北宋 ; 960–1127), the capital was in the northern city of Bianjing (now Kaifeng ) and the dynasty controlled most of what is now East China . The Southern Song ( 南宋 ; 1127–1279) comprise the period following the loss of control over the northern half of Song territory to the Jurchen-led Jin dynasty in the Jin–Song wars . At that time, the Song court retreated south of the Yangtze and established its capital at Lin'an (now Hangzhou ). Although

9135-651: The Shushigaku (朱子學, School of Zhu Xi) of Japan, and in Korea the Jujahak (주자학). Buddhism's continuing influence can be seen in painted artwork such as Lin Tinggui 's Luohan Laundering . However, the ideology was highly criticized and even scorned by some. The statesman and historian Ouyang Xiu (1007–1072) called the religion a "curse" that could only be remedied by uprooting it from Chinese culture and replacing it with Confucian discourse. The Chan sect experienced

9280-723: The Song dynasty alternated between warfare and diplomacy with the ethnic Khitans of the Liao dynasty in the northeast and with the Tanguts of the Western Xia in the northwest. The Song dynasty used military force in an attempt to quell the Liao dynasty and to recapture the Sixteen Prefectures , a territory under Khitan control since 938 that was traditionally considered to be part of China proper (Most parts of today's Beijing and Tianjin ). Song forces were repulsed by

9425-535: The Song dynasty had lost control of the traditional Chinese heartlands around the Yellow River , the Southern Song Empire contained a large population and productive agricultural land, sustaining a robust economy. In 1234, the Jin dynasty was conquered by the Mongols , who took control of northern China, maintaining uneasy relations with the Southern Song. Möngke Khan , the fourth Great Khan of

9570-409: The Song dynasty was able to hold back the Jin, a new foe came to power over the steppe, deserts, and plains north of the Jin dynasty. The Mongols , led by Genghis Khan (r. 1206–1227), initially invaded the Jin dynasty in 1205 and 1209, engaging in large raids across its borders, and in 1211 an enormous Mongol army was assembled to invade the Jin. The Jin dynasty was forced to submit and pay tribute to

9715-519: The Song dynasty, but also the last instance where a war elephant corps was employed as a regular division within a Chinese army. There was a total of 347 military treatises written during the Song period, as listed by the history text of the Song Shi (compiled in 1345). However, only a handful of these military treatises have survived, which includes the Wujing Zongyao written in 1044. It

9860-406: The Song era. The Song dynasty was the first in world history to issue banknotes or true paper money and the first Chinese government to establish a permanent standing navy . This dynasty saw the first surviving records of the chemical formula for gunpowder, the invention of gunpowder weapons such as fire arrows , bombs, and the fire lance . It also saw the first discernment of true north using

10005-416: The Song forces only 3,000 men on 120 warships, the Song dynasty forces were victorious in both battles due to the destructive power of the bombs and the rapid assaults by paddlewheel ships . The strength of the navy was heavily emphasized following these victories. A century after the navy was founded it had grown in size to 52,000 fighting marines. The Song government confiscated portions of land owned by

10150-527: The Song navy that could carry 1,000 soldiers aboard their decks, while the swift-moving paddle-wheel craft were viewed as essential fighting ships in any successful naval battle. In a battle on January 23, 971, massive arrow fire from Song dynasty crossbowmen decimated the war elephant corps of the Southern Han army. This defeat not only marked the eventual submission of the Southern Han to

10295-530: The Song state recognized the Liao state as its diplomatic equal. The Song created an extensive defensive forest along the Song-Liao border to thwart potential Khitan cavalry attacks. The Song dynasty managed to win several military victories over the Tanguts in the early 11th century, culminating in a campaign led by the polymath scientist, general, and statesman Shen Kuo (1031–1095). However, this campaign

10440-492: The Song, the era was known for its regional varieties of performing arts styles as well. Theatrical drama was very popular amongst the elite and general populace, although Classical Chinese —not the vernacular language —was spoken by actors on stage. The four largest drama theatres in Kaifeng could hold audiences of several thousand each. There were also notable domestic pastimes, as people at home enjoyed activities such as

10585-526: The Tang era, would also be revived in China under Mongol rule. Sumptuary laws regulated the food that one consumed and the clothes that one wore according to status and social class. Clothing was made of hemp or cotton cloths, restricted to a color standard of black and white. Trousers were the acceptable attire for peasants, soldiers, artisans, and merchants, although wealthy merchants might choose to wear more ornate clothing and male blouses that came down below

10730-493: The aid of a curative additive. Because of its high performance, moderate ease of manufacturing, and moderate cost, APCP finds widespread use in space, military, and amateur rockets, whereas cheaper and less efficient ANCP finds use in amateur rocketry and gas generators . Ammonium dinitramide , NH 4 N(NO 2 ) 2 , is being considered as a 1-to-1 chlorine-free substitute for ammonium perchlorate in composite propellants. Unlike ammonium nitrate, ADN can be substituted for AP without

10875-1310: The ancient Chinese, and in the 13th century, the Mongols played a pivotal role in facilitating their westward adoption. All rockets used some form of solid or powdered propellant until the 20th century, when liquid-propellant rockets offered more efficient and controllable alternatives. Because of their simplicity and reliability, solid rockets are still used today in military armaments worldwide, model rockets , solid rocket boosters and on larger applications. Since solid-fuel rockets can remain in storage for an extended period without much propellant degradation, and since they almost always launch reliably, they have been frequently used in military applications such as missiles . The lower performance of solid propellants (as compared to liquids) does not favor their use as primary propulsion in modern medium-to-large launch vehicles customarily used for commercial satellites and major space probes. Solids are, however, frequently used as strap-on boosters to increase payload capacity or as spin-stabilized add-on upper stages when higher-than-normal velocities are required. Solid rockets are used as light launch vehicles for low Earth orbit (LEO) payloads under 2 tons or escape payloads up to 500 kilograms (1,100 lb). A simple solid rocket motor consists of

11020-459: The application of electric current. Unlike conventional rocket motor propellants that are difficult to control and extinguish, ESPs can be ignited reliably at precise intervals and durations. It requires no moving parts and the propellant is insensitive to flames or electrical sparks. Solid propellant rocket motors can be bought for use in model rocketry ; they are normally small cylinders of black powder fuel with an integral nozzle and optionally

11165-528: The arts as accepted pastimes of the cultured scholar-official, including painting , composing poetry , and writing calligraphy . The poet and statesman Su Shi and his associate Mi Fu (1051–1107) enjoyed antiquarian affairs, often borrowing or buying art pieces to study and copy. Poetry and literature profited from the rising popularity and development of the ci poetry form . Enormous encyclopedic volumes were compiled, such as works of historiography and dozens of treatises on technical subjects. This included

11310-579: The assault against the Song, gaining a temporary foothold on the southern banks of the Yangtze. By the winter of 1259, Uriyangkhadai's army fought its way north to meet Kublai's army, which was besieging Ezhou in Hubei . Kublai made preparations to take Ezhou , but a pending civil war with his brother Ariq Böke —a rival claimant to the Mongol Khaganate—forced Kublai to move back north with

11455-461: The budding movement of Neo-Confucianism , led by Cheng Yi (1033–1107) and Zhu Xi (1130–1200). Mahayana Buddhism influenced Fan Zhongyan and Wang Anshi through its concept of ethical universalism , while Buddhist metaphysics deeply affected the pre–Neo-Confucian doctrine of Cheng Yi. The philosophical work of Cheng Yi in turn influenced Zhu Xi. Although his writings were not accepted by his contemporary peers, Zhu's commentary and emphasis upon

11600-528: The bulk of his forces. In Kublai's absence, the Song forces were ordered by Chancellor Jia Sidao to make an immediate assault and succeeded in pushing the Mongol forces back to the northern banks of the Yangtze. There were minor border skirmishes until 1265, when Kublai won a significant battle in Sichuan . From 1268 to 1273, Kublai blockaded the Yangtze River with his navy and besieged Xiangyang ,

11745-467: The cargo bay of the Space Shuttle. Star motors have propellant fractions as high as 94.6% but add-on structures and equipment reduce the operating mass fraction by 2% or more. Higher performing solid rocket propellants are used in large strategic missiles (as opposed to commercial launch vehicles). HMX , C 4 H 8 N 4 (NO 2 ) 4 , a nitramine with greater energy than ammonium perchlorate,

11890-452: The casing is often implemented, which ablates to prolong the life of the motor casing. A convergent-divergent design accelerates the exhaust gas out of the nozzle to produce thrust. The nozzle must be constructed from a material that can withstand the heat of the combustion gas flow. Often, heat-resistant carbon-based materials are used, such as amorphous graphite or reinforced carbon–carbon . Some designs include directional control of

12035-511: The central Song court remained politically divided and focused upon its internal affairs, alarming new events to the north in the Liao state finally came to its attention. The Jurchen , a subject tribe of the Liao, rebelled against them and formed their own state, the Jin dynasty (1115–1234) . The Song official Tong Guan (1054–1126) advised Emperor Huizong to form an alliance with the Jurchens, and

12180-464: The cities of Huizhou , Chengdu , Hangzhou , and Anqi. The size of the workforce employed in paper money factories was large; it was recorded in 1175 that the factory at Hangzhou employed more than a thousand workers a day. The economic power of Song China can be attested by the growth of the urban population of its capital city Hangzhou. The population was 200,000 at the start of the 12th century and increased to 500,000 around 1170 and doubled to over

12325-469: The collapse of the Jin dynasty. After the first Mongol invasion of Vietnam in 1258, Mongol general Uriyangkhadai attacked Guangxi from Hanoi as part of a coordinated Mongol attack in 1259 with armies attacking in Sichuan under Mongol leader Möngke Khan and other Mongol armies attacking in modern-day Shandong and Henan . On August 11, 1259, Möngke Khan died during the siege of Diaoyu Castle in Chongqing . His successor Kublai Khan continued

12470-470: The court. Wang Anshi's "New Policies Group" ( Xin Fa ), also known as the "Reformers", were opposed by the ministers in the "Conservative" faction led by the historian and Chancellor Sima Guang (1019–1086). As one faction supplanted another in the majority position of the court ministers, it would demote rival officials and exile them to govern remote frontier regions of the empire. One of the prominent victims of

12615-454: The currently favored APCP solid propellants. With a specific impulse of 309 s already demonstrated by Peacekeeper's second stage using HMX propellant, the higher energy of CL-20 propellant can be expected to increase specific impulse to around 320 s in similar ICBM or launch vehicle upper stage applications, without the explosive hazard of HMX. An attractive attribute for military use is the ability for solid rocket propellant to remain loaded in

12760-413: The dynasty, government posts were disproportionately held by two elite social groups: a founding elite who had ties with the founding emperor and a semi-hereditary professional elite who used long-held clan status, family connections , and marriage alliances to secure appointments. By the late 11th century, the founding elite became obsolete, while political partisanship and factionalism at court undermined

12905-511: The early 11th century to 400,000 candidates by the late 13th century. The civil service and examination system allowed for greater meritocracy , social mobility , and equality in competition for those wishing to attain an official seat in government. Using statistics gathered by the Song state, Edward A. Kracke, Sudō Yoshiyuki, and Ho Ping-ti supported the hypothesis that simply having a father, grandfather, or great-grandfather who had served as an official of state did not guarantee one would obtain

13050-561: The economy. The lower gentry assumed a larger role in local administration and affairs. Song society was vibrant, and cities had lively entertainment quarters. Citizens gathered to view and trade artwork, and intermingled at festivals and in private clubs. The spread of literature and knowledge was enhanced by the rapid expansion of woodblock printing and the 11th-century invention of movable type printing. Philosophers such as Cheng Yi and Zhu Xi reinvigorated Confucianism with new commentary, infused with Buddhist ideals, and emphasized

13195-591: The educational system and state bureaucracy. Seeking to resolve what he saw as state corruption and negligence, Wang implemented a series of reforms called the New Policies . These involved land value tax reform, the establishment of several government monopolies, the support of local militias, and the creation of higher standards for the Imperial examination to make it more practical for men skilled in statecraft to pass. The reforms created political factions in

13340-402: The empire. In one such project, cartographers created detailed maps of each province and city that were then collected in a large atlas . Emperor Taizu also promoted groundbreaking scientific and technological innovations by supporting works like the astronomical clock tower designed and built by the engineer Zhang Sixun . The Song court maintained diplomatic relations with Chola India ,

13485-586: The establishment of retirement homes , public clinics , and paupers ' graveyards . The Song dynasty supported a widespread postal service that was modeled on the earlier Han dynasty (202 BCE – CE 220) postal system to provide swift communication throughout the empire. The central government employed thousands of postal workers of various ranks to provide service for post offices and larger postal stations. In rural areas, farming peasants either owned their own plots of land , paid rents as tenant farmers , or were serfs on large estates. Although women were on

13630-611: The exhaust can turn the smoke opaque. A powdered oxidizer and powdered metal fuel are intimately mixed and immobilized with a rubbery binder (that also acts as a fuel). Composite propellants are often either ammonium-nitrate -based (ANCP) or ammonium-perchlorate -based (APCP). Ammonium nitrate composite propellant often uses magnesium and/or aluminium as fuel and delivers medium performance (I sp of about 210 s (2.1 km/s)) whereas ammonium perchlorate composite propellant often uses aluminium fuel and delivers high performance: vacuum I sp up to 296 s (2.90 km/s) with

13775-542: The exhaust. This can be accomplished by gimballing the nozzle, as in the Space Shuttle SRBs, by the use of jet vanes in the exhaust as in the V-2 rocket, or by liquid injection thrust vectoring (LITV). LITV consists of injecting a liquid into the exhaust stream after the nozzle throat. The liquid then vaporizes, and in most cases chemically reacts, adding mass flow to one side of the exhaust stream and thus providing

13920-447: The famed Bao Zheng (999–1062) embodied the upright, moral judge who upheld justice and never failed to live up to his principles. Song judges specified the guilty person or party in a criminal act and meted out punishments accordingly, often in the form of caning . A guilty individual or parties brought to court for a criminal or civil offense were not viewed as wholly innocent until proven otherwise, while even accusers were viewed with

14065-563: The first industrial manufacture of military rockets with the Congreve rocket in 1804. In 1921 the Soviet research and development laboratory Gas Dynamics Laboratory began developing solid-propellant rockets, which resulted in the first launch in 1928, that flew for approximately 1,300 metres. These rockets were used in 1931 for the world's first successful use of rockets to assist take-off of aircraft . The research continued from 1933 by

14210-451: The flow of iron products from production centres to the large market in the capital city. The annual output of minted copper currency in 1085 reached roughly six billion coins. The most notable advancement in the Song economy was the establishment of the world's first government issued paper-printed money, known as Jiaozi (see also Huizi ). For the printing of paper money , the Song court established several government-run factories in

14355-445: The functional definition of double base propellants. One of the most active areas of solid propellant research is the development of high-energy, minimum-signature propellant using C 6 H 6 N 6 (NO 2 ) 6 CL-20 nitroamine ( China Lake compound #20), which has 14% higher energy per mass and 20% higher energy density than HMX. The new propellant has been successfully developed and tested in tactical rocket motors. The propellant

14500-470: The gooey asphalt, creating a flexible but geometrically stable load-bearing propellant grain that bonded securely to the motor casing. This made possible much larger solid rocket motors. Atlantic Research Corporation significantly boosted composite propellant I sp in 1954 by increasing the amount of powdered aluminium in the propellant to as much as 20%. Solid-propellant rocket technology got its largest boost in technical innovation, size and capability with

14645-400: The government relied upon the cooperation of the few or many local gentry in the area. For example, the Song government—excluding the educational-reformist government under Emperor Huizong—spared little amount of state revenue to maintain prefectural and county schools; instead, the bulk of the funds for schools was drawn from private financing. This limited role of government officials was

14790-440: The grain, failure of case bonding, and air pockets in the grain. All of these produce an instantaneous increase in burn surface area and a corresponding increase in exhaust gas production rate and pressure, which may rupture the casing. Another failure mode is casing seal failure. Seals are required in casings that have to be opened to load the grain. Once a seal fails, hot gas will erode the escape path and result in failure. This

14935-521: The hierarchic social order, a person could gain status and prestige in society by becoming a high-ranking military officer with a record of victorious battles. At its height, the Song military had one million soldiers divided into platoons of 50 troops, companies made of two platoons, battalions composed of 500 soldiers. Crossbowmen were separated from the regular infantry and placed in their own units as they were prized combatants, providing effective missile fire against cavalry charges. The government

15080-414: The importance of proper coroner 's conduct during autopsies and the accurate recording of the inquest of each autopsy by official clerks. The Song military was chiefly organized to ensure that the army could not threaten Imperial control, often at the expense of effectiveness in war. Northern Song's Military Council operated under a Chancellor, who had no control over the imperial army. The imperial army

15225-658: The ingredients necessary for combustion within the chamber in which they are burned. More advanced solid rocket motors can be throttled , or extinguished and re-ignited, by control of the nozzle geometry or through the use of vent ports. Further, pulsed rocket motors that burn in segments, and that can be ignited upon command are available. Modern designs may also include a steerable nozzle for guidance, avionics , recovery hardware ( parachutes ), self-destruct mechanisms, APUs , controllable tactical motors, controllable divert and attitude control motors, and thermal management materials. The medieval Song dynasty Chinese invented

15370-413: The interest in the performance of post-mortem autopsies in China during the 12th century. The physician and judge known as Song Ci (1186–1249) wrote a pioneering work of forensic science on the examination of corpses in order to determine cause of death (strangulation, poisoning, drowning, blows, etc.) and to prove whether death resulted from murder, suicide, or accidental death. Song Ci stressed

15515-495: The joint military campaign under this Alliance Conducted at Sea toppled and completely conquered the Liao dynasty by 1125. During the joint attack, the Song's northern expedition army removed the defensive forest along the Song-Liao border. However, the poor performance and military weakness of the Song army was observed by the Jurchens, who immediately broke the alliance, beginning the Jin–Song Wars of 1125 and 1127. Because of

15660-487: The knee, skirts, and jackets with long or short sleeves, while women from wealthy families could wear purple scarves around their shoulders. The main difference in women's apparel from that of men was that it was fastened on the left, not on the right. The main food staples in the diet of the lower classes remained rice, pork, and salted fish. In 1011, Emperor Zhenzong of Song introduced Champa rice to China from Vietnam 's Kingdom of Champa , which sent 30,000 bushels as

15805-451: The landed gentry in order to raise revenue for these projects, an act which caused dissension and loss of loyalty amongst leading members of Song society but did not stop the Song's defensive preparations. Financial matters were made worse by the fact that many wealthy, land-owning families—some of which had officials working for the government—used their social connections with those in office in order to obtain tax-exempt status. Although

15950-419: The last obstacle in his way to invading the rich Yangtze River basin. Kublai officially declared the creation of the Yuan dynasty in 1271. In 1275, a Song force of 130,000 troops under Chancellor Jia Sidao was defeated by Kublai's newly appointed commander-in-chief, general Bayan . By 1276, most of the Song territory had been captured by Yuan forces, including the capital Lin'an. In the Battle of Yamen on

16095-558: The major cause of Song economic prosperity. Artisans and merchants formed guilds that the state had to deal with when assessing taxes, requisitioning goods, and setting standard workers' wages and prices on goods. The iron industry was pursued by both private entrepreneurs who owned their own smelters as well as government-supervised smelting facilities. The Song economy was stable enough to produce over 100,000,000 kg (220,000,000 lb) of iron products per year. Large-scale Deforestation in China would have continued if not for

16240-412: The marriage strategies of the professional elite, which dissolved as a distinguishable social group and was replaced by a multitude of gentry families. Due to Song's enormous population growth and the body of its appointed scholar-officials being accepted in limited numbers (about 20,000 active officials during the Song period), the larger scholarly gentry class would now take over grassroots affairs on

16385-412: The mix). Almost all sounding rockets use solid motors. Due to reliability, ease of storage and handling, solid rockets are used on missiles and ICBMs. Solid rockets are suitable for launching small payloads to orbital velocities, especially if three or more stages are used. Many of these are based on repurposed ICBMs. Song dynasty The dynasty's history is divided into two periods: during

16530-560: The mix. This extra component usually is in the form of small crystals of RDX or HMX , both of which have higher energy than ammonium perchlorate. Despite a modest increase in specific impulse, implementation is limited due to the increased hazards of the high-explosive additives. Composite modified double base propellants start with a nitrocellulose/nitroglycerin double base propellant as a binder and add solids (typically ammonium perchlorate (AP) and powdered aluminium ) normally used in composite propellants. The ammonium perchlorate makes up

16675-727: The most prosperous and advanced economies in the medieval world. Song Chinese invested their funds in joint stock companies and in multiple sailing vessels at a time when monetary gain was assured from the vigorous overseas trade and domestic trade along the Grand Canal and Yangtze River. Both private and government-controlled industries met the needs of a growing Chinese population in the Song; prominent merchant families and private businesses were allowed to occupy industries that were not already government-operated monopolies. Economic historians emphasize this toleration of market mechanisms over population growth or new farming technologies as

16820-597: The multitude of ships sailing for maritime interests into the waters of the East China Sea and Yellow Sea (to Korea and Japan ), Southeast Asia , the Indian Ocean , and the Red Sea , it was necessary to establish an official standing navy . The Song dynasty therefore established China's first permanent navy in 1132, with a headquarters at Dinghai . With a permanent navy, the Song were prepared to face

16965-460: The naval forces of the Jin on the Yangtze River in 1161, in the Battle of Tangdao and the Battle of Caishi . During these battles the Song navy employed swift paddle wheel driven naval vessels armed with traction trebuchet catapults aboard the decks that launched gunpowder bombs . Although the Jin forces commanded by Wanyan Liang (the Prince of Hailing) boasted 70,000 men on 600 warships, and

17110-420: The next 50 years. By the later 1980s and continuing to 2020, these government-developed highly-capable solid rocket technologies have been applied to orbital spaceflight by many government-directed programs , most often as booster rockets to add extra thrust during the early ascent of their primarily liquid rocket launch vehicles . Some designs have had solid rocket upper stages as well. Examples flying in

17255-569: The oxygen deficit introduced by using nitrocellulose , improving the overall specific impulse. The aluminium improves specific impulse as well as combustion stability. High performing propellants such as NEPE-75 used to fuel the Trident II D-5 SLBM replace most of the AP with polyethylene glycol -bound HMX , further increasing specific impulse. The mixing of composite and double base propellant ingredients has become so common as to blur

17400-401: The political rivalry, the famous poet and statesman Su Shi (1037–1101), was jailed and eventually exiled for criticizing Wang's reforms. The continual alternation between reform and conservatism had effectively weakened the dynasty. This decline can also be attributed to Cai Jing (1047–1126), who was appointed by Emperor Zhezong (1085–1100) and who remained in power until 1125. He revived

17545-463: The propellant surface area exposed to the combustion gases. Since the propellant volume is equal to the cross sectional area A s {\displaystyle A_{s}} times the fuel length, the volumetric propellant consumption rate is the cross section area times the linear burn rate b ˙ {\displaystyle {\dot {b}}} , and the instantaneous mass flow rate of combustion gases generated

17690-407: The recruitment system of officials, increasing the salaries for minor officials, and establishing sponsorship programs to allow a wider range of people to be well educated and eligible for state service. After Fan was forced to step down from his office, Wang Anshi (1021–1086) became Chancellor of the imperial court. With the backing of Emperor Shenzong (1067–1085), Wang Anshi severely criticized

17835-573: The removal of the previous defensive forest, the Jin army marched quickly across the North China Plain to Kaifeng. In the Jingkang Incident during the latter invasion, the Jurchens captured not only the capital, but the retired Emperor Huizong, his successor Emperor Qinzong , and most of the Imperial court. The remaining Song forces regrouped under the self-proclaimed Emperor Gaozong of Song (1127–1162) and withdrew south of

17980-776: The rest of China proper , reuniting much of the territory that had once belonged to the Han and Tang empires and ending the upheaval of the Five Dynasties and Ten Kingdoms period. In Kaifeng , he established a strong central government over the empire. The establishment of this capital marked the start of the Northern Song period. He ensured administrative stability by promoting the civil service examination system of drafting state bureaucrats by skill and merit (instead of aristocratic or military position) and promoted projects that ensured efficiency in communication throughout

18125-417: The retired Peacekeeper ICBMs). The Naval Air Weapons Station at China Lake, California, developed a new compound, C 6 H 6 N 6 (NO 2 ) 6 , called simply CL-20 (China Lake compound 20). Compared to HMX, CL-20 has 14% more energy per mass, 20% more energy per volume, and a higher oxygen-to-fuel ratio. One of the motivations for development of these very high energy density military solid propellants

18270-403: The rocket for long durations and then be reliably launched at a moment's notice. Black powder (gunpowder) is composed of charcoal (fuel), potassium nitrate (oxidizer), and sulfur (fuel and catalyst). It is one of the oldest pyrotechnic compositions with application to rocketry. In modern times, black powder finds use in low-power model rockets (such as Estes and Quest rockets), as it

18415-459: The same level of authority. Robert Hartwell and Robert P. Hymes criticized this model, stating that it places too much emphasis on the role of the nuclear family and considers only three paternal ascendants of exam candidates while ignoring the demographic reality of Song China, the significant proportion of males in each generation that had no surviving sons, and the role of the extended family . Many felt disenfranchised by what they saw as

18560-655: The theory of the Five Elements (wuxing), the earth element follows the fire, the dynastic element of the Song, in the sequence of elemental creation. Therefore, their ideological move showed that the Jin considered Song reign in China complete, with the Jin replacing the Song as the rightful rulers of China Proper. Although weakened and pushed south beyond the Huai River , the Southern Song found new ways to bolster its strong economy and defend itself against

18705-472: The use of intermediary agents. The Song judicial system retained most of the legal code of the earlier Tang dynasty, the basis of traditional Chinese law up until the modern era. Roving sheriffs maintained law and order in the municipal jurisdictions and occasionally ventured into the countryside. Official magistrates overseeing court cases were not only expected to be well-versed in written law but also to promote morality in society. Magistrates such as

18850-616: The various mid-20th century government initiatives to develop increasingly capable military missiles. After initial designs of ballistic missile military technology designed with liquid-propellant rockets in the 1940s and 1950s, both the Soviet Union and the United States embarked on major initiatives to develop solid-propellant local , regional , and intercontinental ballistic missiles, including solid-propellant missiles that could be launched from air or sea . Many other governments also developed these military technologies over

18995-404: The vast local level. Excluding the scholar-officials in office, this elite social class consisted of exam candidates, examination degree-holders not yet assigned to an official post, local tutors, and retired officials. These learned men, degree-holders, and local elites supervised local affairs and sponsored necessary facilities of local communities; any local magistrate appointed to his office by

19140-518: The waist. Acceptable apparel for scholar-officials was rigidly defined by the social ranking system. However, as time went on this rule of rank-graded apparel for officials was not as strictly enforced. Each official was able to display his awarded status by wearing different-colored traditional silken robes that hung to the ground around his feet, specific types of headgear, and even specific styles of girdles that displayed his graded-rank of officialdom. Women wore long dresses, blouses that came down to

19285-530: The waving of banners and to halt at the sound of bells and drums. The Song navy was of great importance during the consolidation of the empire in the 10th century; during the war against the Southern Tang state, the Song navy employed tactics such as defending large floating pontoon bridges across the Yangtze River in order to secure movements of troops and supplies. There were large ships in

19430-452: Was an era of administrative sophistication and complex social organization. Some of the largest cities in the world were found in China during this period (Kaifeng and Hangzhou had populations of over a million). People enjoyed various social clubs and entertainment in the cities, and there were many schools and temples to provide the people with education and religious services. The Song government supported social welfare programs including

19575-462: Was demoted, being given the title 'Duke of Ying', but was eventually exiled to Tibet where he took up a monastic life. The former emperor would eventually be forced to commit suicide under the orders of Kublai's great-great-grandson, Gegeen Khan , out of fear that Emperor Gong would stage a coup to restore his reign. Other members of the Song imperial family continued to live in the Yuan dynasty, including Zhao Mengfu and Zhao Yong. The Song dynasty

19720-476: Was divided among three marshals, each independently responsible to the Emperor. Since the Emperor rarely led campaigns personally, Song forces lacked unity of command. The imperial court often believed that successful generals endangered royal authority, and relieved or even executed them (notably Li Gang, Yue Fei, and Han Shizhong ). Although the scholar-officials viewed military soldiers as lower members in

19865-582: Was eager to sponsor new crossbow designs that could shoot at longer ranges, while crossbowmen were also valuable when employed as long-range snipers . Song cavalry employed a slew of different weapons, including halberds, swords, bows, spears, and ' fire lances ' that discharged a gunpowder blast of flame and shrapnel . Military strategy and military training were treated as sciences that could be studied and perfected; soldiers were tested in their skills of using weaponry and in their athletic ability. The troops were trained to follow signal standards to advance at

20010-498: Was rarely consumed since the bull was a valuable draft animal, and dog meat was absent from the diet of the wealthy, although the poor could choose to eat dog meat if necessary (yet it was not part of their regular diet). People also consumed dates , raisins, jujubes , pears, plums, apricots, pear juice, lychee -fruit juice, honey and ginger drinks, spices and seasonings of Sichuan pepper , ginger , soy sauce, vegetable oil, sesame oil, salt, and vinegar. The Song dynasty had one of

20155-488: Was the cause of the Space Shuttle Challenger disaster . Solid rocket fuel deflagrates from the surface of exposed propellant in the combustion chamber. In this fashion, the geometry of the propellant inside the rocket motor plays an important role in the overall motor performance. As the surface of the propellant burns, the shape evolves (a subject of study in internal ballistics), most often changing

20300-565: Was the eighth emperor of the Song dynasty and he was a renowned artist as well as a patron of the art and the catalogue of his collection listed over 6,000 known paintings. A prime example of a highly venerated court painter was Zhang Zeduan (1085–1145) who painted an enormous panoramic painting , Along the River During the Qingming Festival . Emperor Gaozong of Song initiated a massive art project during his reign, known as

20445-512: Was the first known book to have listed formulas for gunpowder; it gave appropriate formulas for use in several different kinds of gunpowder bombs. It also provided detailed descriptions and illustrations of double-piston pump flamethrowers , as well as instructions for the maintenance and repair of the components and equipment used in the device. The visual arts during the Song dynasty were heightened by new developments such as advances in landscape and portrait painting. The gentry elite engaged in

20590-423: Was two minutes. The nozzle throat was large enough to walk through standing up. The motor was capable of serving as a 1-to-1 replacement for the 8-engine Saturn I liquid-propellant first stage but was never used as such. Motor 260 SL-3 was of similar length and weight but had a maximum thrust of 24 MN (5,400,000 lbf) and a shorter duration. Design begins with the total impulse required, which determines

20735-503: Was ultimately a failure due to a rival military officer of Shen disobeying direct orders, and the territory gained from the Western Xia was eventually lost. The Song fought against the Vietnamese kingdom of Đại Việt twice, the first conflict in 981 and later a significant war from 1075 to 1077 over a border dispute and the Song's severing of commercial relations with Đại Việt. After the Vietnamese forces inflicted heavy damages in

20880-407: Was used for the space shuttle boosters . Filament-wound graphite epoxy casings are used for high-performance motors. The casing must be designed to withstand the pressure and resulting stresses of the rocket motor, possibly at elevated temperature. For design, the casing is considered a pressure vessel . To protect the casing from corrosive hot gases, a sacrificial thermal liner on the inside of

21025-673: Was used in the propellant of the Peacekeeper ICBM and is the main ingredient in NEPE-75 propellant used in the Trident II D-5 Fleet Ballistic Missile. It is because of explosive hazard that the higher energy military solid propellants containing HMX are not used in commercial launch vehicles except when the LV is an adapted ballistic missile already containing HMX propellant (Minotaur IV and V based on

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