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| 1 | Spatio-temporal rupture process of the 2008 great Wenchuan earthquake显示文摘Focal mechanism and dynamic rupture process of the Wenchaun Ms8.0 earthquake in Sichuan province on 12 May 2008 were obtained by inverting long period seismic data from the Global Seismic Network (GSN), and characteristics of the co-seismic displacement field near the fault were quantitatively ana-lyzed based on the inverted results to investigate the mechanism causing disaster. A finite fault model with given focal mechanism and vertical components of the long period P-waves from 21 stations with evenly azimuthal coverage were adopted in the inversion. From the inverted results as well as after-shock distribution, the causative fault of the great Wenchuan earthquake was confirmed to be a fault of strike 225°/dip 39°/rake 120°, indicating that the earthquake was mainly a thrust event with right-lateral strike-slip component. The released scalar seismic moment was estimated to be about 9.4×1020―2.0×1021 Nm, yielding moment magnitude of Mw7.9―8.1. The great Wenchuan earthquake occurred on a fault more than 300 km long, and had a complicated rupture process of about 90 s duration time. The slip distribution was highly inhomogeneous with the average slip of about 2.4 m. Four slip-patches broke the ground surface. Two of them were underneath the regions of Wenchuan-Yingxiu and Beichuan, respectively, with the first being around the hypocenter (rupture initiation point), where the largest slip was about 7.3 m, and the second being underneath Beichuan and extending to Pingwu, where the largest slip was about 5.6 m. The other two slip-patches had smaller sizes, one having the maximum slip of 1.8 m and lying underneath the north of Kangding, and the other having the maximum slip of 0.7 m and lying underneath the northeast of Qingchuan. Average and maximum stress drops over the whole fault plane were estimated to be 18 MPa and 53 MPa, respectively. In addition, the co-seismic displacement field near the fault was analyzed. The results indicate that the features of the co-seismic displacement field were coincident with those of the intensity distribution in the meizo-seismal area, implying that the large-scale, large-amplitude and surface-broken thrust dislocation should be responsible for the serious disaster in the near fault area. | ZHANG Yong FENG WanPeng XU LiSheng ZHOU ChengHu CHEN YunTai | 2009 | Science China Earth Sciences2009,52,2: | 68 |
| 2 | 降雨强度和坡度双因子对紫色土坡面侵蚀产沙的影响显示文摘利用室内模拟降雨试验研究了降雨强度和坡度双因子对紫色土坡面侵蚀产沙过程的影响。试验结果表明:坡面产沙过程和侵蚀形态的演变与降雨强度和坡度的变化密切相关,降雨强度和坡度增大使径流量很快达到细沟发生的临界流量并加剧细沟形态的演变过程,产沙率由于细沟的产生和发展而急剧增加,并呈现跳跃性的波动。各降雨强度下,在5°~25°范围内,侵蚀量随坡度的增大而增大,30°时开始减小,在25°附近存在坡面侵蚀的临界坡度。降雨强度和坡度两个因子对侵蚀量的贡献率存在对比消长关系。降雨强度和坡度都较小时,坡度对侵蚀过程起主导作用;当降雨强度较大或者达到临界坡度以后,则降雨强度对侵蚀过程起主导作用。 | 耿晓东 郑粉莉 刘力 | 2010 | 泥沙研究2010,35,6: | 66 |
| 3 | Uplift of the Tibetan Plateau and environmental changes显示文摘Major progress, problems, and challenges of recent investigation of the Tibetan Plateau uplift processes and resulting environmental changes are reviewed and summarized briefly, which especially covers the National Tibetan Research Projects of the Chinese Eighth (1992-1996) and Ninth (1997-2001) 'Five-Year Projects'. The Tibetan Plateau uplift is a complicated multiple cyclic process. The Gangdise and Himalayas began to uplift in the | Jijun Li Xiaomin Fang | 1999 | Chinese Science Bulletin1999,44,23: | 66 |
| 4 | 水利水电工程施工安全管理与安全控制显示文摘针对事故隐患,论述了事故隐患与危险源关系,指出了事故隐患形成原因,并提出了排查事故隐患与治理整改方案、防范及控制措施,以供水利水电工程安全管理借鉴。 | 郑霞忠 肖玲 张光飞 | 2010 | 水电能源科学2010,28,10: | 54 |
| 5 | Entransy dissipation minimization for liquid-solid phase change processes显示文摘The liquid-solid phase change process of a simple one-dimensional slab is studied in this paper.By taking entransy dissipation minimization as optimization objective,the optimal external reservoir temperature profiles are derived by using optimal control theory under the condition of a fixed freezing or melting time.The entransy dissipation corresponding to the optimal heat exchange strategies of minimum entransy dissipation is 8/9 of that corresponding to constant reservoir temperature operations,which is independent of all system parameters.The obtained results for entransy dissipation minimization are also compared with those obtained for the optimal heat exchange strategies of minimum entropy generation and constant reservoir temperature operations by numerical examples.The obtained results can provide some theoretical guidelines for the choice of optimal cooling or heating strategy in practical liquid-solid phase change processes. | XIA ShaoJun,CHEN LinGen & SUN FengRui Postgraduate School,Naval University of Engineering,Wuhan 430033,China | 2010 | Science China(Technological Sciences)2010,53,4: | 41 |
| 6 | Impacts of thermodynamic processes over the Tibetan Plateau on the Northern Hemispheric climate显示文摘We here report our recent research results on the climatic features of Tibetan thermodynamic functions and their impacts on the regional climates of the Northern Hemisphere. The results show that the thermodynamic processes over the Tibetan Plateau not only strongly influence the Asian monsoon and precipitation, but also modulate the atmospheric circulation and climate over North America and Europe through stimulating the large-scale teleconnections such as the Asian-Pacific oscillation and affect the atmospheric circulation over the southern Indian Ocean. The Tibetan climate may be affected by sea surface temperatures over the tropical Pacific. On the other hand, the Tibetan climate also affects the atmosphere-ocean interactions in the tropics and mid-latitudes of the Pacific by the atmospheric circulation over the North Pacific. In spring and summer, the thermodynamic anomalies on the plateau affect the subtropical high pressure, the Hadley circulation, and the intertropical convergence zone over the Pacific, and then modulate the development of the El Ni-o/Southern Oscillation (ENSO). It is necessary to study the forecasting methods for the development of ENSO from the Tibetan climate anomaly. This result also embodies the essence of interactions among land, atmosphere, and ocean over the Northern Hemisphere. Since the previous studies focused on impacts of the plateau on climates in the Asian monsoon regions, it is essential to pay more attention to studying the roles of the plateau in the Northern Hemispheric and even global climates. | ZHOU XiuJi ZHAO Ping CHEN JunMing CHEN LongXun LI WeiLiang | 2009 | Science China Earth Sciences2009,52,11: | 42 |
| 7 | 东准噶尔卡拉麦里地区黄羊山花岗岩和包体LA-ICP-MS锆石U-Pb测年及地质意义显示文摘高精度LA-ICP-MS锆石U-Pb测年结果表明,黄羊山岩浆混合花岗岩加权平均^(206)Pb/^(238)U年龄为311±12Ma,首次获得闪长质微细粒包体加权平均^(206)Pb/^(238)U年龄为300±6Ma,在误差范围内完全一致,均属于晚石炭世,前者代表黄羊山岩浆混合花岗岩成岩年龄,后者代表暗色闪长质微粒包体的形成年龄,表明两者是同时代形成的,属于300Ma前后准噶尔周边地区后碰撞岩浆活动的产物。岩石地球化学研究表明,寄主岩石具有高硅、低铝、贫钙镁、富碱和高分异的特征,寄主岩石、包体和辉绿岩脉成分均落在了混合趋势线上,寄主岩富集Rb和Th等大离子亲石元素及Zr、Hf等高场强元素,亏损Ba、Sr、Ta和Ti等元素,δEu值(为0.01)极低,具有低的^(87)Sr/^(86)Sr初始比值和高正的ε_(Nd)(t)值。黄羊山碱性花岗岩是在后碰撞拉张的构造背景下,幔源岩浆发生底垫作用,由于幔源岩浆底垫作用,下地壳温度升高而熔融形成酸性壳源岩浆,部分幔源岩浆沿着地壳中的深断裂带上涌,发生不同程度壳幔混合形成的,其中闪长质微细粒包体就是基性的幔源岩浆和酸性的壳源岩浆不同程度的混合的记录者,研究区的辉绿岩脉是幔源岩浆直接分异演化的产物。 | 杨高学 李永军 吴宏恩 司国辉 金朝 张永智 | 2009 | 岩石学报2009,25,12: | 46 |
| 8 | Rising process of the Qinghai-Xizang (Tibet) Plateau and its mechanism显示文摘The rising of the Qinghai-Xizang Plateau has character of multistage (45-38 Ma, 25-17 Ma, 13-8 Ma, 3 Ma-present), inhomogeneity and hetero-speed. The whole uprising of the plateau and local rapid rising in its periphery since Late Pliocene is a synthetical result of at least two or more mechanisms. | 钟大赉 丁林 | 1996 | Science China Earth Sciences1996,39,4: | 49 |
| 9 | Antimony speciation in the environment:Recent advances in understanding the biogeochemical processes and ecological effects显示文摘Antimony(Sb) is a toxic metalloid, and its pollution has become a global environmental problem as a result of its extensive use and corresponding Sb-mining activities. The toxicity and mobility of Sb strongly depend on its chemical speciation. In this review, we summarize the current knowledge on the biogeochemical processes(including emission, distribution,speciation, redox, metabolism and toxicity) that trigger the mobilization and transformation of Sb from pollution sources to the surrounding environment. Natural phenomena such as weathering, biological activity and volcanic activity, together with anthropogenic inputs, are responsible for the emission of Sb into the environment. Sb emitted in the environment can adsorb and undergo redox reactions on organic or inorganic environmental media, thus changing its existing form and exerting toxic effects on the ecosystem. This review is based on a careful and systematic collection of the latest papers during 2010–2017 and our research results, and it illustrates the fate and ecological effects of Sb in the environment. | Mengchang He Ningning Wang Xiaojing Long Chengjun Zhang Congli Ma Qianyun Zhong Aihua Wang Ying Wang Aneesa Pervaiz Jun Shan | 2019 | Journal of Environmental Sciences2019,31,1: | 40 |
| 10 | Concerned topics of epidural labor analgesia:labor elongation and maternal pyrexia:a systematic review显示文摘Objective:Labor is a complex process and labor pain presents challenges for analgesia.Epidural analgesia(EA)has a well-known analgesic effect and is commonly used during labor.This review summarized frequently encountered and controversial problems surrounding EA during labor,including the labor process and maternal intrapartum fever,to build knowledge in this area.Data sources:We searched for relevant articles published up to 2019 in PubMed using a range of search terms(eg,“labor pain,”“epidural,”“analgesia,”“labor process,”“maternal pyrexia,”“intrapartum fever”).Study selection:The search returned 835 articles,including randomized control trials,retrospective cohort studies,observational studies,and reviews.The articles were screened by title,abstract,and then full-text,with a sample independently screened by two authors.Thirty-eight articles were included in our final analysis;20 articles concerned the labor process and 18 reported on maternal pyrexia during EA.Results:Four classic prospective studies including 14,326 participants compared early and delayed initiation of EA by the incidence of cesarean delivery.Early initiation following an analgesia request was preferred.However,it was controversial whether continuous use of EA in the second stage of labor induced adverse maternal and neonatal outcomes due to changes in analgesic and epidural infusion regimens.There was a high incidence of maternal pyrexia in women receiving EA and women with placental inflammation or histologic chorioamnionitis compared with those receiving systemic opioids.Conclusions:Early EA(cervical dilation≥1 cm)does not increase the risk for cesarean section.Continuous epidural application of low doses of analgesics and programmed intermittent epidural bolus do not prolong second-stage labor duration or impact maternal and neonatal outcomes.The association between EA and maternal pyrexia remains controversial,but pyrexia is more common with EA than without.A non-infectious inflammatory process is an accepted mechanism of epidural-related maternal fever. | Cai-Juan Li Fan Xia Shi-Qin Xu Xiao-Feng Shen | 2020 | Chinese Medical Journal2020,,5: | 35 |
| 11 | Thawing and freezing processes of active layer in Wudaoliang region of Tibetan Plateau显示文摘The interaction between permafrost and atmosphere is accomplished through transfer of heat and moisture in the overlay active layer. Thus, the research on the thermal and hydrodynamics of active layer during the thawing and freezing processes was considered a key to revealing the heat and moisture exchanges between permafrost and atmosphere. The monitoring and research on active layer were conducted because permafrost occupies about two thirds of the total area of the Tibetan Plateau. Based on the analysis of the ground temperature data and soil moisture data of monitoring near the Wudaoliang region of the Tibetan Plateau, the thawing and freezing processes of active layer were divided into four stages, i.e. summer thawing stage (ST), autumn freezing stage (AF), winter cooling stage (WC) and spring warming stage (SW). Coupled heat and water flow is much more complicated in ST and AF, and more amount of water is migrating in these two stages. Heat is transferred mainly via conductive heat flow in the | Lin Zhao Guodong Cheng Shuxun Li Xinmin Zhao Shaoling Wang | 2000 | Chinese Science Bulletin2000,45,23: | 31 |
| 12 | The construction of Markov processes in random environments and the equivalence theorems显示文摘In sec.1, we introduce several basic concepts such as random transition function, p-m process and Markov process in random environment and give some examples to construct a random transition function from a non-homogeneous density function. In sec.2, we construct the Markov process in random enviromment and skew product Markov process by p - m process and investigate the properties of Markov process in random environment and the original process and environment process and skew product process. In sec. 3, we give several equivalence theorems on Markov process in random environment. | HU DiheSchool of Mathematics and Statistics, Wuhan University, Wuhan 430072, China | 2004 | Science China Mathematics2004,47,4: | 27 |
| 13 | Episodic rifting of continental marginal basins and tectonic events since 10 Ma in the South China Sea显示文摘Integrated study on the tectonic, basin filling and thermal evolution of the Tertiary basins on the northern margin of the South China Sea has indicated that the rift continental margin on the northern South China Sea is not a passive margin and that the western margin is characteristic of the transformextension. Episodic rifting and the thermal events since 10 Ma in the area have been documented by the integrated analysis of dynamic process. It has been clarified that the tectono-thermal events have exerted a significant influence on basin features and hydrocarbon accumulation, and particularly, the westward collision of the Lusong Island Arc, the generation of densely spaced faults in the Pearl River Mouth Basin, the rapid subsidence, high heat flow and large-scale over pressure and thermal-fluid breakthrough in the Yinggehai and the Qiongdongnan basins have proved to be the important factors determining the formation of oil and gas in these basins. | Sitian Li Changsong Lin Qiming Zhang Shigong Yang Peikan Wu | 1999 | Chinese Science Bulletin1999,44,1: | 27 |
| 14 | NUMERICAL SIMULATION OF ROUND TO OVAL ROLLING PROCESS显示文摘Three dimensional thermal-mechanical coupled elasto-plastic FEM has been used for simulation of round to oval single pass rolling. The analysis was conducted using MARC/AUTOFORCE1. 2 code. The material is assumed to be elasto-plastic and it obey the Von Mises yield criterion and Prandtl- Reuss rule. Deformation of the workpiece is simulated in a step-by-step manner,updating the coordinates of material points and the property after each step, so that both nonsteady-state and stendy-state deformation can be simulated. The heat transfter between the workpiece, the rolls, and enviroment and the heat generation due to plastic work and friction force, are considered in the analys- is.Predicted the deformation shape of the workpiece, distributions of strains, stresses, strain rates and temperatures, roll-separating force and roll torque are presented. | Y. W. Wang, Y. L. King, D. H. Yuan, S. G. Liu and Z. Y. Yu 1 ) University of Science and Technology Beijing, Beijing 100083, China 2) Daye Special Steel Co., Huangshi 435001, China | 2000 | Acta Metallurgica Sinica(English Letters)2000,13,2: | 27 |
| 15 | Lithosphere types in North China:Evidence from geology and geophysics显示文摘On the basis of the characteristics of geology and geophysics in North China, three types of lithosphere, namely, the cratonic, the orogenic and the rift lithospheres can be classified. In terms of petrological method (based on the information from Precambrian rock assemblages, igneous activities, deep-seated enclaves, etc.) and the relationship between seismic velocity and rock compositions, the crust-mantle petrological and chemical structure models can be set up. Researching results indicate that the geology and geophysics of North China platform bears the similar characteristics in comparison with those of the global typical cratons. The Eerduosi(Ordos) block located in the west of the North China Platform is a remnant of cratonic lithosphere after the North China platform had undergone “activation” in Mesozoic and “reconstruction” in Cenozoic times. The continental crust consists mainly of TTG rock assemblage while the subcontinental lithosphere mantle mainly consists of strongly depleted harzburgite. The craton was finally formed in late Archaean and early Proterozoic, and has been kept in stability up to present; its crustal-mantle petrological structures of lithosphere can be set up as a reference for the study of North China craton and even Sino-Korean craton. In the Mesozoic period, the middle and east areas of North China platform were activated in the Yanshanian orogenic process, the continental crust was reformed by material and heat-transfer of convective mantle and the original crustal TTG component was reconstructed to be granitic crust, and the subcontinental lithosphere man- tle was replaced by the Yanshanian harzburgite-lherzolite. The Yanshan-Taihang Mountains were the remnants of orogenic lithosphere after the rifting in eastern North China in Cenozoic. The present thickness of continental crust and lithosphere in the Yanshan-Taihang Mountains is not equal to their thickness during the Yanshanian orogenic movement because they had undergone the crustal extensional thinning in Cenozoic, however, the material and structure of lithosphere mantle-crust were formed during the Yanshanian orogenic movement. In the Cenozoic Period, the rift-type lithosphere, as represented by the North China plain, was formed by the continental rifting occurring in the eastern part of North China. The continental granitic crust, which had been “acidified” at the Yanshanian period, was basified again by the eruption of basalt magma along the continental rifting, and the subcontinental lithosphere mantle formed in Yanshanian was de- stroyed and replaced by the Himalayan mantle which consists mainly of lherzolite. Both the crust and the lithospheric mantle in the rift have undergone extensional thinning and thermal erosion at lithospheric-scale, the material and structure of the present mantle-crust lithosphere, attained from geophysical exploration, was formed in Cenozoic. The formation and evolution of litho- sphere in North China indicate that the material and heat transferred by convective mantle into the continental crust was the key for different types of lithosphere forming, and the crust-mantle petrologic structure was the records of lithosphere evolution, and it was the integrated results of the deep processes of the China continental dynamic system and the Pacific Plate subduction located in the eastern margin of the North China platform in Mesozoic-Cenozoic time. | QIU Ruizhao1,2, DENG Jinfu3, ZHOU Su3, LI Jinfa4, XIAO Qinghui1,5, WU Zongxu6 & LIU Cui3 1. Institute of Geology, Chinese Academy of Geological Sciences, Beijing 100037, China 2. Development and Research Center, China Geological Survey, Beijing 100037, China 3. China University of Geosciences, Beijing 100083, China 4. China University of Geosciences, Wuhan 430074, China 5. Information Center of Ministry of Land and Resources, Beijing 100812, China 6. Institute of Geology, State Seismological Bureau, Beijing 100029, China | 2005 | Science China Earth Sciences2005,48,11: | 25 |
| 16 | Deep process of the collision and deformation on the northern margin of the Tibetan Plateau:Revelation from investigation of the deep seismic profiles显示文摘The seismic investigation achievements from three kinds of methods have revealed the lithospheric structure and the deep process of deformation caused by collision. It is found that convergent collision and deep subduction of the continental lithosphere are in progress along the northern margin of the Tibetan Plateau. The deep process of due collision and deformation is different from that of oblique collision. It is revealed in the study that the deep process of the collision and deformation on the northern margin is different from that on the southern margin of the Tibetan Plateau. | 高锐 李朋武 李秋生 管烨 史大年 孔祥儒 刘宏兵 | 2001 | Science China Earth Sciences2001,44,S1: | 26 |
| 17 | 他们不再是孩子了 关于“新失业群体”现状的社会学报告显示文摘The “New Unemployed” consists of young people with low education in the Chinese cities. They differ from the cohorts of their parents because they have no work experiences in any state- or collective-owned enterprise, and are subject to completely different policies designated by the government. Investigations of their daily living lead to the conclusion that the “New Unemployed” has gone through a “system withdrawal” process. They are now facing an environment of “system vacuum” that none of other unemployed groups has ever encountered before. The author emphasizes in the paper a strategic employment principle of “For Future Generations” so that focused attention and care can be provided and this toughest challenge in China can be dealt with. | 吕鹏 | 2005 | 社会2005,25,4: | 26 |
| 18 | Diagnostic Study on the Structural Characteristics of a Typical Mei-yu Front System and Its Maintenance Mechanism显示文摘In this paper, a typical mei-yu front process with heavy rainfall from June 12 to 15 in 1998 is analyzed. The results show that the mei-yu front is a front system which consists of an iso-θe dense area with strong horizontal gradient, a deep-convective cloud tower band, a passageway transporting warm and moist air ?ow from the summer monsoon surge in the mid and low levels to the south of the mei-yu front, and a migrating synoptic scale trough to the north of the mei-yu front, which transports cold and dry air southward in the mid and upper levels. The maintenance of the mei-yu front is realized by: (1) is a positive feedback between the moist physical process enhancing frontogenesis and the development of the strong convective system in front of the mei-yu front; (2) the sustaining system to the north of the mei-yu front which is a migrating synoptic scale trough transporting cold and dry air to the mei-yu front and positive vorticity to the mesoscale system in front of the mei-yu front. | JIANG Jianying(蒋建莹) NI Yunqi(倪允琪) | 2004 | Advances in Atmospheric Sciences2004,21,5: | 22 |
| 19 | Fundamental Theories and Key Technologies for Smart andOptimal Manufacturing in the Process Industry显示文摘Given the significant requirements for transforming and promoting the process industry, we present themajor limitations of current petrochemical enterprises, including limitations in decision-making, produc-tion operation, efficiency and security, information integration, and so forth. To promote a vision of theprocess industry with efficient, green, and smart production, modern information technology should beutilized throughout the entire optimization process for production, management, and marketing. To focuson smart equipment in manufacturing processes, as well as on the adaptive intelligent optimization of themanufacturing process, operating mode, and supply chain management, we put forward several key scien-tific problems in engineering in a demand-driven and application-oriented manner, namely:intelligentsensing and integration of all process information, including production and management information; collaborative decision-making in the supply chain, industry chain, and value chain, driven by knowledge; cooperative control and optimization of plant-wide production processes via human-cyber-physical in-teraction; and Q life-cycle assessments for safety and environmental footprint monitoring, in addition totracing analysis and risk control. In order to solve these limitations and core scientific problems, we furtherpresent fundamental theories and key technologies for smart and optimal manufacturing in the processindustry. Although this paper discusses the process industry in China, the conclusions in this paper can beextended to the larocess industry around the world. | Feng Qian Weimin Zhong Wenli Du | 2017 | Engineering2017,3,2: | 23 |
| 20 | Metabolic analyses reveal different mechanisms of leaf color change in two purple-leaf tea plant (Camellia sinensis L.) cultivars显示文摘Purple-leaf tea plants,as anthocyanin-rich cultivars,are valuable materials for manufacturing teas with unique colors or flavors.In this study,a new purple-leaf cultivar“Zixin”(“ZX”)was examined,and its biochemical variation and mechanism of leaf color change were elucidated.The metabolomes of leaves of“ZX”at completely purple,intermediately purple,and completely green stages were analyzed using ultra-performance liquid chromatography quadrupole time of flight mass spectrometry(UPLC-QTOF-MS).Metabolites in the flavonoid biosynthetic pathway remained at high levels in purple leaves,whereas intermediates of porphyrin and chlorophyll metabolism and carotenoid biosynthesis exhibited high levels in green leaves.In addition,fatty acid metabolism was more active in purple leaves,and steroids maintained higher levels in green leaves.Saponin,alcohol,organic acid,and terpenoid-related metabolites also changed significantly during the leaf color change process.Furthermore,the substance changes between“ZX”and“Zijuan”(a thoroughly studied purple-leaf cultivar)were also compared.The leaf color change in“Zijuan”was mainly caused by a decrease in flavonoids/anthocyanins.However,a decrease in flavonoids/anthocyanins,an enhancement of porphyrin,chlorophyll metabolism,carotenoid biosynthesis,and steroids,and a decrease in fatty acids synergistically caused the leaf color change in“ZX”.These findings will facilitate comprehensive research on the regulatory mechanisms of leaf color change in purple-leaf tea cultivars. | Jiazhi Shen Zhongwei Zou Xuzhou Zhang Lin Zhou Yuhua Wang Wanping Fang Xujun Zhu | 2018 | Horticulture Research2018,5,1: | 22 |