In recent years, a number of Chinese technological innovation(科技创新) have been making waves around the world. Among them, four stand out. They are known as "four new great inventions" of modern China. They have made our daily lives more convenient

High-speed trains

    China created its first high-speed railway line in 2008. Since then, the number of passenger trips has grown by over 30 percent every year. By 2016, more than 5 billion trips had been taken China's bullet trains(高铁), according to Xinhua News Agency.

    China is currently working on the next-generation bullet trains that will have a top speed of 400kilometers per hour. By 2020, one-fifth of the country's 150,000-km railway network will be used by high-speed trains. This network will link more than 80percent of major cities across China, said Xinhua.

Mobile payment

    Mobile payment is turning China into a "cashless society" led by third-party payment companies like Alipay. For example, instead of paying y cash, customers now pay for goods simply by typing a short password into Alipay app on their mobile devices.

    Users can also pay their bills through Alipay, such as their water and electricity bills. Alipay also supports cross-border(跨境的)online and in-store payment, which allows users to buy things on international websites and apps.

Shared bikes

    Shared bike services started in Western countries. But China has surprised the world with how quickly it has adopted dockless(无桩的)shared bikes.

    Unlike traditional bike-sharing method, dockless bikes allow users to simply pick up or park a bike on the street through GPS and smartphone To unlock a bike, you just need to scan a QR code on a shared bike with a smartphone app     After you finish riding, you can park it at available parking areas, lock it and pay for ride through mobile payment services.

Online shopping

    With around 751 million internet users, China has long been the world's largest and fastest-growing online shopping market.

    Online shopping now accounts for 15.5 percent of total retail sales in China, according to Xinhua. Thanks to lower costs and fewer licensing requirements(执照要求),it's easier for sellers to open an online shop in China than a brick-and-mortar shop(实体店)。

    It also helped to create jobs of rural areas. In 2016, online shopping created more than 20 million jobs in rural areas, with over 8.1 million running their own online shops, said Xinhua.

注意个人卫生要做到：____、____、____。

 现有一包白色固体样品，可能含有BaCl₂、Na₂SO₄、Na₂CO₃、NH₄HCO₃、KCl、CuSO₄中的一种或几种，取样品进行如下实验：

（1）操作1所用到是玻璃仪器有____ ．

（2）原白色固体中一定不含有____ ，一定含有____ ．

（3）写出生成气体a的化学方程式____ ．

                                                                                                     唐朝为什么以胖为美
                                                                                                                王彬
        ①如果去观赏唐代绘画、雕塑、陶俑及其他各类艺术作品所表现的女性形象，留给大家最突出的印象，也一定是“丰肥浓丽、热烈放姿”。丰肥浓丽即丰满、肥硕、浓艳、亮丽，热烈放姿即穿着袒露、自信张扬的表情姿态。虽然仔细观察，唐代三百年间的女性形象也有一个由清秀到丰肥、穿着由拘谨到开放的渐变过程，但是，给人视觉冲击力最强、最具感染力和令人过目难忘的，还是那些盛唐时期姿态万千、装束大胆、乐观向上的胖美人形象。
　    ②几千年来，中国有着“事死如事生”的生死观念。在这一观念影响下，工匠们仿照“生人”的模样精心塑造了唐朝的女性形象。综观留存下来的美女雕像和图画，虽然工艺有别，年龄有少女、少妇之差，但大多面如满月、丰颊秀眉、腰肢圆浑，其装扮袒露而大胆。即使被今人誉之为中国古代第一美人的“捧杯侍女”，除了婀娜的捧杯姿态与众不同之外，其基本特征仍然是“丰肥浓丽、热烈放姿”。
　　③显然，无论是艺术作品还是现实生活都清晰地反映出，唐人的确崇尚“丰肥浓丽、热烈放姿”。这与汉代和古代大多数时期人们欣赏窈窕淑女含蓄内向的审美观不同，并形成了唐代的“另类”审美眼光。然而，这种“另类”和有悖于传统的丰肥之美的魅力，不仅丝毫不逊色于传统的苗条和骨感，而且更具生命力和向上的朝气。其实，我们稍加分析就会发现，唐人的“另类”审美正是那个如日中天时代的必然特点。
　　④首先，唐代繁荣昌盛、丰衣足食，正如诗圣杜甫诗句所记“稻米流脂粟米白，公私仓禀俱丰实”。人们有条件吃饱穿暖保持健康丰满的体格。其次，唐代开放兼容并包。国力强盛与文明发达，使唐人充满自信，成为一个高度开放的国家。据不完全统计，当时与唐交往的国家有130多个。不同文化的影响、交融，使唐人不拘于传统，眼界开阔，热烈放姿。第三，统治者的血统也决定了唐人对健硕的体魄更易亲近。唐代开国皇帝李渊的外祖父是鲜卑大贵族独孤如愿，也就是说李唐皇室的血统中至少有一半是鲜卑血统，而鲜卑族的游牧生活造就和需要的是剽悍、健硕的体魄。因此，唐朝几代国君均宠爱丰肥的女性也就不难理解了。
       ⑤透过唐人独特的审美眼光，不难看到当时崇尚的“丰肥浓丽、热烈放姿”绝不单纯是女性体态上的肥、瘦，穿着上的遮、露。可以说，这种审美取向是一种全方位的审美理念，所体现的是一种力量型的、开放兼容的文化视野。唐人喜爱牡丹，而牡丹的花型正是高贵丰满。唐人塑造的骏马形象每件都是骠满臀圆。而唐代影响最大的颜体书法更是肥硕、庄严而浑厚。韩愈有诗道：“书贵瘦硬吾不取”，也体现了唐人价值取向由瘦硬向“肥硕”的转变。
　　⑥如果把视野放得更大一些，就会发现，唐都长安城是当时世界上最大的都城，马路是最宽阔的，宫殿是最高峻宏伟的，当时的中国是世界向往的中心。这一切体现了一个民族进入高度成熟、处于生命力最旺盛阶段洋溢出的蓬勃朝气和高度自信，使唐人崇尚并醉心于一种气魄、力量和开张的美，而这种美传递给我们的是一种扑面而来的时代气息--热烈放姿、开拓进取、积极向上。