News on China's scientific and technological development.

by78

General
From Zhuhai airshow.

52481349818_0dc4e41ddf_3k.jpg
52480805286_b96859cea0_3k.jpg
 

sunnymaxi

Major
Registered Member
Please, Log in or Register to view URLs content!

China to Build Three Manufacturing Innovation Centers, Shares of Related Firms Soar

(Yicai Global) Nov. 7 -- Shares of Chinese firms in the graphene, virtual reality and ultra-high-definition video industries surged today, following the government’s decision to build three national-level manufacturing innovation centers related to the three sectors.

Shenzhen-based Ofilm Group [SHE: 002456] surged by the daily 10 percent limit to close at CNY5.45 (USD0.8).

The main entity responsible for building the innovation center for the VR industry is an Ofilm-affiliated firm, in which Ofilm owns a 20 percent stake, news outlet the 21st Century Business Herald reported today, citing Oflim’s investor relation department.

With support from the Nanchang Virtual Reality Institute, a national VR innovation center will be built in Nanchang, Jiangxi province, the Ministry of Industry and Information Technology said in a statement published on its website today.

The center will carry out key technology research and development, testing, and verification while offering technical services as well as talent training and international cooperation, the ministry noted.

A national graphene innovation center will be built in Ningbo, Zhejiang province, relying on a firm called Ningbo Graphene Innovation Center, the MIIT noted, adding that a national UHD video innovation center will be set up with the backing of a Chengdu, Sichuan province-based startup.

Deluxe Family [SHA: 600503], a Shanghai-based property and scientific and technological industry investment firm, also rose by the daily limit of 10 percent today to end the day at CNY2.88. Deluxe Family holds about 1 percent stake in Ningbo Graphene Innovation Center, the news outlet said.

Business registration data showed television maker Sichuan Changhong Electric is the Chengdu-based startup’s fourth largest shareholder and set top box maker Sichuan Jiuzhou Electronic is its sixth biggest shareholder. Changhong [SHA: 600839] shares gained 1.9 percent to CNY2.76 today, while Jiuzhou [SHE: 000801] rose by 1.7 percent at CNY8.32.

The MIIT will work with local departments to advance the construction of the three innovation centers, enhancing technical innovation ability and providing strong support for the development of key areas of the manufacturing industry, it said in the statement.
 

sunnymaxi

Major
Registered Member
World's 1st tunnel boring machine for high slope spiral tunnel construction arrived at a construction site in NW China's Gansu. The 100-m-long machine with a diameter of over 7 m will help build a world-class underground laboratory for high-level radioactive waste disposal..

FhBPRdtVsAIhMEq.jpgFhBPRduVEAI3mB9.jpgFhBPRduVEAE5_xo.jpg
 

SanWenYu

Captain
Registered Member
Chinese scientists made breakthrough in core technologies of thin-disk lasers. They are able to create a 72-pass pump module with their own IPs.

Thin-disk laser is a new kind of solid state lasers and has great potentials in EUV light source, frequency comb, etc. Multi-pass pump modules are the most important component in thin-disk lasers. They are on the embargo list from the west.



Please, Log in or Register to view URLs content!

Abstract​

Beam quality and average output power are two long-sought parameters of continuous-wave lasers. The operating characteristics of a Yb:YAG thin-disk laser based on a 72-pass pump module using output couplers with continuously variable coupling rates are reported. When the pump power is 450 W, the average power of more than 210 W is obtained, and the corresponding optical-optical efficiency is about 46.67%. The output beam is near diffraction limited with M2=1.20 and 1.18 on the horizontal and vertical directions respectively. The thin-disk laser maintains the beam quality near diffraction limited within the whole pump power range by continuously changing the coupling rate of the output coupler (the combination of thin film polarizer and quarter-wave plate) according to the incident pump power. The experimental results show that by continuously changing the coupling rate, combined with the dynamic change of thermal lens effect, the laser beam quality factor M2 can be reduced from 2.0 to 1.2, and the beam quality can be improved by about 40%. The improvement of and increase of average output power confirm that resonators with continuously variable coupling rate are a promising method for enhancing output performance of thin-disk lasers.

Please, Log in or Register to view URLs content!

近日,我所化学激光研究室(七室)李刚研究员、金玉奇研究员团队在薄片激光器光束质量控制研究方面取得新进展,提出了一种在全泵浦功率范围内使薄片激光器连续输出并保持光束质量接近衍射极限的新方法,并对其光束质量控制机理进行了深入研究。

薄片激光器是一种半导体泵浦的、增益介质为薄片状晶体的新型固体激光器。薄片激光器同时具备高平均功率、高脉冲能量、高光束质量的特性,在EUV光源、光学频率梳和阿秒脉冲产生、激光微加工以及国防领域具有重要应用前景。然而,薄片激光器中最核心的多通泵浦薄片模块技术常年为国外所垄断,且72通泵浦模块对国内禁售。

本工作中,科研人员提出了一种薄片激光多通泵浦方案,并设计制造了自主知识产权的72通泵浦模块,以此为基础开发了一种在全泵浦功率范围内使薄片激光器输出激光的光束质量保持衍射极限的方法。该方法的核心是通过将薄膜偏振片和四分之一波片组合成一个新型输出耦合器,从而实现激光谐振腔的输出耦合率连续线性可调。通过实时调谐谐振腔的输出耦合率,在整个入射泵浦功率范围内都获得了接近衍射极限的光束质量(M2<1.2),平均输出功率超过210W。科研人员通过谐振腔衍射损耗模拟仿真给出了光束质量控制机理。对于类似通过衍射损耗实现基模横输出的谐振腔,连续可变输出耦合器在增强薄片激光器输出性能方面有着良好的应用前景,这为将来的千瓦级纳秒激光器和焦耳级皮秒激光放大器的研制奠定了良好的基础。

该团队在薄片激光器的研制方面,经过多年的技术攻关,此前取得了系列研究进展,包括薄片多通泵浦模块的主动对准技术,用于薄片增益晶体的多孔泡沫结构冷却排列系统,研制了最新一代的72通薄片泵浦模块以及百kHz高功率腔倒空薄片纳秒激光器,基于72通泵浦模块的百fs克尔透镜锁模薄片激光器(《中国激光》,2022)等。

相关研究成果以“Resonators with a continuously variable output coupling rate to enhance output performance of Yb:YAG thin-disk lasers”为题,于近日发表在Optics Express上。该工作的第一作者是我所704组博士研究生戴隆辉。上述工作得到大连市科技创新基金、我所创新基金等项目的支持。(文/图 戴隆辉)
 

FairAndUnbiased

Brigadier
Registered Member
Is she a US citizen ? Can the US ban this one as well ? ;)

in the future perhaps the US would ban Chinese name in the US too
nope. Note that they listed her as a foreign associate of US National Academy of Sciences. She's also never lived in the US continuously for over 5 years except during her PhD.

Please, Log in or Register to view URLs content!
 

SanWenYu

Captain
Registered Member
Harbin Engineering University tested two prototypes of 潜空跨介质航行器 which are able to swim under water and fly in air.

Please, Log in or Register to view URLs content!

让飞机会潜水,让潜器会飞翔!哈工程潜空跨介质航行器试飞成功​

据微信公号“哈尔滨工程大学”11月4日消息,波光粼粼的水面上,两架“小飞机”先后潜入水下,用几十秒的时间抵达指定位置,完成任务后,以优美的转身轻盈飞出水面。

这是两架名为“长弓1号”和“长弓2号”的潜空跨介质航行器,由哈尔滨工程大学水下机器人技术国家级重点实验室历时一年多打造。两款航行器分别采用了固定翼和折叠翼结构,均能够迅速跨越水空介质,在空中稳定飞行,在水下隐蔽航行,全过程全自主,无需人工控制。

负重1千克,潜深100米,潜空跨介质航行器试飞成功

金秋十月,在五常市龙凤山水库,随着通信信号的消失,“长弓1号”开始了自主跨域航行之旅。40多秒后,螺旋桨划破水面,熟悉的马达声传入耳中,“长弓1号”露出水面,随着机体内水的排出,“长弓1号”自主调整飞行姿态,迅速腾空飞离水面,以良好稳定的出水姿态完成了水-空介质跨越过程,不负众望地在空中实现了稳定飞行。

2.jpg3.png
1.gif

Please, Log in or Register to view URLs content!
Please, Log in or Register to view URLs content!
 
Top