日本成人激情_久久久免费精品视频_亚洲激情四射视频中文字幕久久_日本wwwwww_男女做爰裸体猛烈吃奶摸视频_日韩大片在线观看

position: EnglishChannel  > InnovationChina> Plowing a Place in History

Plowing a Place in History

Source: Science and Technology Daily | 2023-09-04 17:03:11 | Author: BI Weizi


Quyuan plow. (PHOTO:VCG)

By BI Weizi

Chinese people have long known how to use oxen and horses to pull carts, with cattle being the main draft animal. However, it was after Spring and Autumn Period (770 BC-476 BC), that animal husbandry was rapidly popularized throughout the country, and the frame structure of the plow was basically established in the Han Dynasty (202 BC-220) and continuously improved with the needs of production.

In the Tang Dynasty (618-907), the curved-shaft plow, later called the Quyuan plow, was invented on the basis of two oxen pulling the plow. It needed only one ox to pull it and had a perfect structure that was light, flexible and could adjust the digging depth.

Compared with previous plows, the Quyuan plow had two main features: first, the straight and long shaft was changed into a curved and short one, and a shaft head was invented and installed so that it could rotate freely. The plow disc not only makes the plow frame smaller and lighter, but also facilitates flexible operation, thus saving manpower and animal power.

Second, the plow blade and plow arrows are added. When the plow blade is pushed forward, the plow arrows can be moved downward. When the blade is pushed forward, the plowshare penetrates deep into the soil. Moreover, the earth could be turned away from the blade because the arms were also curved, which both reduced friction and more effectively plowed the soil.

The organic combination of arrows and plowshares adapted to the different requirements of deep and shallow plowing and facilitated intensive farming.

The invention of the Quyuan plow, which had been used for more than a thousand years, is a milestone in the country's history of agricultural development.

Editor:龍云

Top News

Forging a Resilient Economy with Sci-tech Power

Tiangong Ultra, developed by the Beijing Humanoid Robot Innovation Center, won the world's first half-marathon for humanoid robots in Beijing on April 19, demonstrating the prospects of China's humanoid robot industry and the epitome of the country's strategic emerging industries and future industries. These industries are surging ahead, facilitating the construction of a resilient economy with sci-tech force.

抱歉,您使用的瀏覽器版本過低或開啟了瀏覽器兼容模式,這會影響您正常瀏覽本網頁

您可以進行以下操作:

1.將瀏覽器切換回極速模式

2.點擊下面圖標升級或更換您的瀏覽器

3.暫不升級,繼續瀏覽

繼續瀏覽
主站蜘蛛池模板: 精品无码久久久久久久久久_国产jjizz一区二区三区视频_婷婷一级片_国产在线看片网站_国产AV午夜精品一区二区三区_免费一级在线观看_亚洲一二区制服无码中字_人人妻人人澡人人爽精品日本 | 狠狠干天天_找老女人泻火对白自拍_强开少妇嫩苞又嫩又紧九色_日本激情网_国产精品亚洲人成在99www_亚洲一级理论片_国产青榴视频在线观看_国产一精品 | 国产19页_亚洲日韩精品欧美一区二区_日本中文字幕视频在线观看_国产在线看片_中文字幕AⅤ在线视频_亚洲鲁丝片一区二区三区_亚洲1区_亚洲午夜一区 | a级小视频_无码欧精品亜州日韩一区夜夜嗨_国产精品乱战久久久_91在线看黄_国内大量揄拍人妻在线视频_日本在线视频免费看_国产大片www_无线乱码一二三区免费看 | 久久久久影视_欧美亚洲日本一区_国产精品久久久久久久免费_六月婷色_精品日韩在线视频_麻豆文化传媒www网站入口_精品国产美女a久久9999_亚欧美一区二区 | 浪潮av色综合久久天堂_澳门久久精品_免费观看国产成人_老子影院午夜_伦理三区_久久久7_久久国产精品一区二区_久久泄欲网久久精品性色 | 免费网站看v片在线成人国产..._日本嫩草_搜索黄色毛片_亚洲在线一区_自拍超碰在线_国产99久久久久_91精品国产亚一区二区三区老牛_国产午夜福利久久网 | 人人擦人人干_亚洲日本黄色_最新国产毛片_国产精品IGAO视频网_亚洲一区二区在线视频_JAPANXXXⅩ日本人妻HD_一吻成瘾动漫免费观看_免费看的一级毛片 | 亚洲精品久久久久无码AV片软件_日本国产欧美大码a视频_欧美一区二区三区视频在线_久久国产精品偷_日本午夜精品视频_日日干夜夜撸_www.久色_欧美视频完全免费看 | 成人97精品毛片免费看_中国china体内裑精亚洲片_jiujiure国产_宅男在线免费视频_精品视频久久_日本伊人中文字幕_女子被狂揉下部羞羞图片_精品久久香蕉国产线看观看亚洲 | 激情伊人五月天久久综合_放荡少妇张开双腿任人玩_国产一区二区久久久_99国产在线精品_国产在线视频一区二区_成人一区二_成人一级视频在线观看_a成人毛片 | 国产视频2区_传媒大片免费在线观看网站_久久久不卡_91av在线免费看_亚洲av永久无码精品网站mmd_黑色正能量最新入库_一本色综合久久_97色视频在线 | 91色爱_1100lu永久网址_亚洲AV无码AV男人的天堂_国产日韩一区二区三区四区_天天爱天天做天天爽_98久久_亚洲黄色小说图片_在线观看瑟瑟 | 久久免费成人网_欧美一级黄_日韩色在线_成人免费一级视频_麻豆资源在线观看_性爱在线免费视频_亚洲第一视频区_国产美女午夜福利久久 | 国产精品自在拍视频首页_中文字幕乱码亚洲无线码按摩_成人激情视频在线观看_www.四虎com_国产在线视频99_2002亚洲精品真实在线_国产精选在线播放_色先锋影音岛国av资源 | 九七午夜剧场福利写真_两性色黄视频在线观看_男ji大巴进入女人的视频免费看_亚洲永久免费_久久久线视频_国产麻豆影院_97爱爱视频_日本一级黄色大片 | 欧美图片小说_欧洲日韩在线观看_妞干网免费_国产精品视频一区在线观看_精品黄色录像_精品少妇人妻av一区二区_大香伊蕉在人线国产av_国产精品亚洲欧美卡通动漫 | 日产一级毛片_日韩精品www_午夜老司机在线观看_国产欧美二区_亚洲av产在线精品亚洲第一站_日本少妇色xxxxx中国免费看_香港一级毛片_色男人天堂 | 四虎4hu永久免费_无码精品A在线观看无_精品久久人妻AV中文字幕_国产成A人亚洲精V品无码_日本xxxx网站_国产乱magnet_中文字幕无码日韩专区_久久久久亚洲精品无码网址蜜桃 | 一夲道无码人妻精品一区二区_视频一区三区_国产精品一区二区日韩新区_在线精品自拍视频_九一嫩草_日本黄区免费视频观看_CHINESE性内射高清国产_国产精品一区在线 | a级小视频_无码欧精品亜州日韩一区夜夜嗨_国产精品乱战久久久_91在线看黄_国内大量揄拍人妻在线视频_日本在线视频免费看_国产大片www_无线乱码一二三区免费看 | 中文字幕日日_无码国产精品一区二区免费式芒果_免费日韩精品_caoporn免费在线视频_最近2019中文免费高清视频观看www99_欧美超逼视频_国产成人激情_dvd女人裸体 | 亚洲自拍偷拍一区_a4yy午夜_久久久久九九九九_国产超碰av_777久久精品一区二区三区无码_黑人粗硬进入过程视频_av在线收看_中国高清av | 老鸭窝视频在线观看_chinese国产人妖ts_狠狠躁夜夜躁人人躁婷婷91_2021av在线_亚洲成AV人片在线观看无线_国产看片网站_69精品人人人人人人人人人_亚洲欧美色中文字幕在线 | 国产精品www劲爽视频_国产青草视频在线观看视频_日韩欧美群交P片內射中文_成人观看av_av永久免费大全网站_日产精品最新在线_久久人人网_国产精品一七六九在线是免费 | 日韩第一视频_香蕉影院在线_无套内射无矿码免费看黄_千金不装了短剧免费观看_九九久久国产_爆乳2把你榨干哦无码_三级小说一区_国产在线观看91一区二区三区 | 国产一级网_亚洲av成人无码天堂_CHINA丰满人妻VIDEOSHD_国产黄色a级毛片_日本午夜免费_国产男女做爰高清全过小说_日本免费二区三区_日韩在线观看视频一区二区 | 美女裸体爆乳免费网站_亚洲欧美精品国产一级在线_欧美日韩二_四虎库影必出精品8848_b站免费直接观看_九九免费_性欢交69国产精品_午夜提供人体 | 日日干夜夜爱_欧美交换配乱吟粗大免费看_三级免费黄_最新中文字幕第一页_把腿张开老子cao烂你_国产系列精品av_国产中文字幕免费_韩国av网站在线观看 | 欧美日韩一道本_欧美日韩在线视频不卡一区二区三区_亚州黄色_三区四区在线观看_不卡视频一区二区_亚洲免费观看视频_国产一级黄色录像_欧美男男激情videos高清 | 精品久久久久久亚洲综合网_久爱视频精品_亚洲夜色_成+人+网+站+免费观看_亚洲av成人永久无在线观看_性色一区_又湿又紧又大又爽A视频国产_日本SM极度另类视频 | 欧美人妖XXXX做受_少妇群交换bd高清国语版_日本久久精_免费动漫黄爽A片在线观看_国产清纯白嫩初高生在线播放视频_综合激情视频_欧美一级黄色片子_蜜桃av噜噜一区二区三区策驰 | 西西大尺度美軳人人体bt_蜜臀在线一区_欧美三级午夜理伦三级富婆_亚洲中文无码线在线观看_亚洲性夜色噜噜噜7777_女人做爰高潮时叫要精免费的视频_大黄网站免费在线观看_亚洲天堂岛国片 | 国产亚洲情侣一区二区无_亚洲精品视频免费观看_樱桃视频大全免费观看_撕开奶罩揉吮奶头高潮av_成人免费精品网站在线观看影片_va在线观看_欧美爆乳精品国产一区二区三区_久久久久亚洲AV无码A片男男 | 一二三四视频社区在线播放中国_91视频免费在线看_色妹子综合网_亚洲中文字幕无线无码毛片_天天操狠狠操_a在线视频观看_日本xxxⅹ18一20岁_www.91精品视频 | 久草免费视_激情影院网站_男人天堂2023_日本成人免费观看_亚洲综合无码一区二区三区不卡_欧美激情猛片xxxⅹ大3_奇米影视7777狠狠狠狠色_中文91 | 日本亚洲国产_毛片毛片毛片毛片毛片毛片小_在线观看无码AV免费不卡网站_国产精品视频公开费视频_黑色蕾丝丝袜麻麻好紧好爽_日本道久久_国产亚洲精AA在线观看不卡_成人爽a毛片免费视频 | 午夜福利09不卡片在线机视频_最新超碰_国产视频999_粉嫩国产一区二区三区免费_亚洲福利一区二区_国产xxxx色视频在线观看_欧美一级特黄aaaa_亚洲av伊人久久青青草原 | 日韩精品视频在线一区二区三区_欧美丰满老妇熟乱xxxxyyy_四虎影视国产精品永久在线_精品自拍av_久久99国产亚洲高清观看首页_五月色夜婷婷丁香琪琪_无码少妇一区二区三区浪潮AV_全黄特一级 | 99ri精品国产亚洲_精品国产乱码久久久久久蜜臀_制服在线无码专区_中文字幕无线乱码人妻_国产精品毛片一区二区在线_丁香婷婷六月综合网_亚洲永久av_久久久亚洲欧美 | 精品久久久久久亚洲综合网_久爱视频精品_亚洲夜色_成+人+网+站+免费观看_亚洲av成人永久无在线观看_性色一区_又湿又紧又大又爽A视频国产_日本SM极度另类视频 |