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China’s auto exports top 1 million for second straight month in July, NEV shipments surge 145.5% amid strong global demand_我的网站

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根据实验结果来看，研究有效验证了星地链路高精度光频标比对的可行性，向建立广域光频标网络迈出重要一步。    

    Robots assemble a new-energy passenger vehicle at Liuzhou Wuling Automobile Industry Co in Liuzhou, South China's Guangxi Zhuang Autonomous Region, on July 18, 2026. Photo: VCG
China's auto exports maintained strong growth in July, with shipments exceeding 1 million units for two consecutive months in June and July, according to the China Association of Automobile Manufacturers (CAAM) released on Wednesday, and new-energy vehicle (NEV) exports were particularly strong.
The latest data show that China exported 1.043 million vehicles in July, up 0.6 percent month-on-month and 81.3 percent year-on-year. Auto exports had already exceeded 900,000 units in both April and May, before rising above 1 million units in both June and July.
Notably, NEV exports were particularly upbeat. China exported 553,000 NEVs in July, up 5.7 percent month-on-month and 145.5 percent year-on-year. NEVs have accounted for more than half of China's total auto exports for two consecutive months.
The rapid growth in China's auto exports is mainly attributed to the country's complete automotive industrial chain, the CCTV News reported, citing a representative with the CAAM. From lithium processing and battery manufacturing to electric motors, control systems and vehicle assembly, China has sufficient production capacity, competitive costs and a highly resilient supply chain, said the representative.
The continued growth in NEV exports reflects rising global demand for cost-effective Chinese products and the needs of the global green transition, Cui Dongshu, secretary-general of the China Passenger Car Association, told the Global Times on Wednesday, noting that China's highly coordinated NEV ecosystem enables faster technological and product upgrades while keeping costs under control, giving the industry a key competitive edge.
Among China's top 10 auto exporters, Chery exported 1.141 million vehicles in the first seven months of the year, up 71 percent year-on-year and accounting for 18.6 percent of total exports. Tesla recorded the fastest growth from a year earlier, with exports reaching 295,000 units, up 130 percent, according to the CAAM.
"Despite rising trade barriers in the US and Europe, China's NEV exports continue to grow rapidly, reflecting strong global demand. Trade restrictions may shift export flows, but cannot easily curb demand for competitive products," said Cui.
Meanwhile, Chinese NEV companies are diversifying its markets, with regions such as Southeast Asia playing a growing role.
The domestic market remained the largest market for NEVs. In the first seven months, NEVs accounted for 53.2 percent of domestic auto sales, according to the CAAM. 
The booming demand for China-made NEVs at home and abroad also rebuts the "overcapacity" narrative pushed by some Western media and politicians, as facts and figures show that demand is outpacing supply, Cui said.
An official from China's Ministry of Commerce told a press conference on July 28 that China has the world's largest consumer market, providing a testing ground for new technologies, products and services. The country has ranked first globally in NEV sales for 11 consecutive years.
China has built a complete and highly efficient NEV industrial system covering the entire chain, from basic materials and auto parts to complete vehicles and manufacturing equipment, with globally leading supply chain responsiveness, cost control and delivery speed.
"A complete, efficient and innovative automotive ecosystem is the result of long-term market competition and industrial development... It cannot be easily replicated in the short term or weakened by tariffs and trade barriers," Cui said.
The industry veteran said that looking ahead, China's NEV competitiveness will increasingly be measured not just by exports, but by the global presence of its companies, technologies and supply chains, as domestic automakers shift from mainly exporting vehicles to building production, supply chains and service networks overseas.
。对此，中国科学技术大学张强教授表示：将来如果放在卫星上能做洲际的时间比对，我们就可以实现新一代的“秒”定义。为什么“秒”要被重新定义了？咱们现在经常提到的时间概念“秒”，是自 1976 年以来，一直由铯-33 原子钟来定义的。原子钟最初是英国物理学家 Louis Esseb 创造，它的工作原理是计算原子中的电子自旋的翻转频率。

二 | 而在 1976 年这一年，科学家们通过铯-133 原子在微波频率下的跳动，重新定义了这个时间基本单位：1 秒 = 铯原子的电子自旋翻转 9192631770 次的持续时间。虽然说这种方式已经够精确了，但科学家们似乎却不满足于此。截至目前，自然领域中对时间的测量精度已经步入 10-19 的量级。这种量级通俗点来讲，就是百亿年期间误差不会超过 1 秒。而且时间是目前七大基本物理量中测量最精确的那一个。但单有最精确的计时还是不够的，因为它还需要“配套”一个与之精度相匹配的时间传递技术。二者的重要性可以说是画等号的。但地面附近自由空间的环境复杂，大气中的各种扰动、湍流、链路损耗、环境变化等因素，给自由空间长距离时频传递带来了极大困难。

三 | 此前，自由空间中的光频传输技术只能实现 10 公里量级的传输。而潘建伟团队要攻克的正是这一难题：在光源方面，研制出高功率、高稳定度光输。在光信号收发信道方面，研制出高稳定性、高效率的光收发望远镜系统。

四 | 还采用线性光学采样的干涉测量方式，实现了高精度的时间测量。最终，潘建伟团队在相隔 113 公里的新疆南山天文台和高崖子天文台之间，实现了万秒 10-19 量级稳定度的时频传递。
据张强介绍：把我们非常精密的这种时间信号，通过这个望远镜打到这个 100 公里以外的另外一个望远镜。那边的话，然后我的这个信号被那边的一个同样的一个望远镜接收，接收了之后他们进行一些比较精密的时间探测。同时那边也会打一个同样的一个精密的光源信号也打过来，在这边也做一个同样的一个精密探测，然后两边的信号再做一个对准，做一个校正。

五 |
据了解，该实验在如此自由空间时频传递过程中：时间传递万秒稳定度达到飞秒量级，频率传递万秒稳定度优于 4E-19，系统相对偏差为 6.3E-20±3.4E-19，系统可容忍最大链路损耗高达 89dB，远高于中高轨星地链路损耗的典型预期值（约 78dB）。
而国际计量组织计划 2026 年讨论“秒”定义的变更，也正因这项研究成果的实现，张强认为：如果能够实现洲际的比对的话，那么我们就可以实现新一代的这个“秒”定义。与日常生活相关那么接下来的一个问题便是，这项研究成果会带来哪些影响？引用 Nature 审稿人的评价就是：该工作是星地自由空间远距离光学时间频率传递领域的一项重大突破，将对暗物质探测、物理学基本常数检验、相对论检验等基础物理学研究产生重要影响。但除此之外，其实这项研究也与人们的日常生活息息相关。例如卫星的导航精度与计时精度紧密相关，若是希望定位更加准确（毫米以下），就需要更好的计时精度。

六 | 在大地测量、地质勘探、雷达探测等涉及社会民生的领域，精确的时间也都将发挥重要的作用。

七 | 那么对于未来新“秒”的定义，你期待了吗？参考链接：[1]https://www.nature.com/articles/s41586-022-05228-5[2]https://weibo.com/2032139271/Mb1zivEhA?type=comment[3]https://mp.weixin.qq.com/s/MCbQ6UJFNflzF0VmrtPw4Q[4]https://tv.cctv.com/2022/10/06/VIDEYEjxB0UTcY85WichtWvz221006.shtml?spm=C45404.PCHhhgX3efBE.Ev0XVtu8CoWN.224[5]https://ishare.ifeng.com/c/s/v002EZ3vLgfck1LPf29qCKM51b4D1bqKqLDSTFiDq8nGUgw__。

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