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Byron Wan

@Byron_Wan

Dec 20, 2025

🚨 China’s most advanced reactor, a molten-salt reactor that can be refueled without shutting it down, was the result of collaboration with American scientists.

This April, in a speech given at the Shanghai branch of the Chinese Academy of Sciences, physicist Xu Hongjie (徐洪杰) announced a breakthrough. For over a decade, his team had been working on an experimental nuclear reactor that runs on a lava-hot solution of fissile material and molten salt, rather than on solid fuel. The reactor, which went online two years ago, was a feat in itself. It is still the only one of its kind in operation in the world, and has the potential to be both safer and more efficient than the water-cooled nuclear plants that dominate the industry. Now, Xu explained, his team had been able to refuel the reactor without shutting it down, demonstrating a level of mastery over their new system.

This was yet another sign that the technology gap between China and the US had closed.

Xu explained that his team had based their design on an experimental reactor that had been built in Tennessee in the 1960’s. Known as the Molten-Salt Reactor Experiment, or the MSRE., that project hit a dead end in the early 1970’s, when it lost federal funding. Xu’s team had learned everything they could about the MSRE so that, decades later, they could bring the project back to life. Xu compared their labors to the story of the tortoise and the hare: whereas the US had “gotten lazy and made a mistake,” China had seized the “chance to overtake” it.

In reality, China’s molten-salt reactor was less the product of a race than a collaboration. Less than ten years earlier, Xu’s team had been working with an array of American nuclear scientists. MIT had irradiated graphite samples for the Chinese scientists. Nuclear engineers from Berkeley flew to Shanghai to review the original design. And by 2015, at what was perhaps the peak of US-China amity in the sciences, Xu’s home institution, the Shanghai Institute of Applied Physics, or SINAP, had signed a coöperative R&D agreement with Tennessee’s Oak Ridge National Laboratory, the site of the world’s first molten-salt reactor.

These agreements could be seen as products of Reagan-era neoliberalism. They allow national labs to hire out their facilities and staff to outside entities that, in exchange for funding, can secure a proprietary claim to any technologies US national labs discover while working on the designated project. For the most part, this has facilitated technology transfer from public institutions to the private sector. But the agreement between ORNL and SINAP created an unprecedented situation: a Chinese state-owned lab was paying an American lab millions of dollars to develop materials and plumbing for molten-salt reactors.

From the start, the American side operated under the belief that the Chinese would be the first to build a molten-salt reactor. China was spending the money to do it, after all. There was some funding for molten-salt research in America, but much less than was needed, and this was why the Oak Ridge researchers were willing to accept support from the Chinese. Through the partnership, the American researchers were hoping to advance work on a less complex reactor, in which molten salt would be used as a coolant rather than a fuel line.

Ten years later, the armature of assumptions and policies that enabled such a partnership has been blown apart. After Donald Trump won the 2016 Presidential election, the Department of Energy severed ties with SINAP and threatened to revoke licenses from American companies that exported nuclear technology to China. During Trump’s second term, the Administration’s hostility toward China has only increased.

Xu passed away while at work at his desk in Sep.

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newyorker.com/news/the-lede/…

To make sense of what is happening in nuclear energy today, it helps to know about what was once called “the first nuclear era” — a 37-year stretch between 1942, when Enrico Fermi oversaw the first controlled fission chain reaction, and 1979, when the second reactor at the Three Mile Island Nuclear Generating Station partially melted down. At the height of this period, around 1960, the US accounted for almost 70% of global spending on R&D. Nuclear energy, which sat at the nexus of defense and civil engineering, was a double beneficiary. From these investments came a series of ever more terrifying weapons alongside a fleet of experimental and commercial reactors that made the US the world’s largest producer of nuclear energy. America still holds this title, but China is poised to assume the mantle, probably sometime around 2030.

The MSRE epitomized the possibilities of this period. The concept originated in the late 1940’s, with a request from the Air Force to develop a nuclear-powered airplane. Alvin Weinberg, who later became the director of research at ORNL, didn’t think that such an aircraft would fly, but he was willing to try to build one. He had helped develop the reactors that produced plutonium for the Manhattan Project and moved to East Tennessee, after the war. There, he presided over the development of ORNL, which grew from a plutonium-production facility near the Clinch River. For Weinberg, the purpose of a national lab was to try “things too difficult or too risky for private industry to undertake.” An airplane that burned uranium was precisely that.

Weinberg wrote that the reactor would need to reach temperatures around 1,500 degrees Fahrenheit in order to power a jet engine. His team surmised that such heat would mangle any fuel rods small enough to install into an aircraft, so they decided to use fluoride salts. These melted into a liquid at around 400 degrees Celsius and stayed stable above 1,600 degrees. With uranium fluoride mixed in, the molten salt itself could function as fuel.

The system went critical in Nov 1954. In its brief life, it showed some remarkable properties, but the test also revealed some of the challenges of working with molten salt. Leaks were a constant problem, and the radiotoxicity of most of the apparatus made repairs next to impossible. As a stopgap, Weinberg’s team had to repeatedly off-gas the reactor compartment, bathing a nearby forest in radioactive xenon and iodine. At the hundred-hour mark, the project was shut down.

The MSRE gave him another shot. By then, the Atomic Energy Commission was ready to make major investments in order to develop breeder reactors, or reactors that produce more fissile material than they burn. Breeder reactors promised energy on a scale far beyond what could be provided by the global supply of coal and oil, fuels that were projected to become scarce within a century and which were already suspected of warming the Earth. Planning began in 1960, and five years later Weinberg’s team loaded 69kg of enriched uranium into the salt. This time, the experiment was a success. The MSRE logged over 13,000 operational hours, during which the researchers ran countless tests. “ They did, like, every calculation you could have done at the time to understand how you would build and run and fuel this reactor.” The most important finding was a simple one: the MSRE proved that a molten-salt reactor was viable.

Weinberg had hoped to move from the MSRE to a molten-salt breeder reactor. But in 1973 President Richard Nixon pulled federal funding for molten-salt research in order to go all-in on a competing breeder reactor that was cooled with sodium. In 1983, the sodium breeder, in turn, lost its funding. Plagued by budget overages, the project also fell victim to a conservative revolt, spearheaded by the Heritage Foundation. By then, the public had also soured on nuclear-energy projects, owing to the partial meltdown at Three Mile Island, in 1979.

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There are various ways to index the downturn of the US nuclear industry, but the starkest is probably by permits. From 1954 to 1978, regulators issued 133 construction permits for civilian nuclear reactors. Between 1979 and 2012, they issued none. “There’s been almost no real work on nuclear power since the seventies … The Department of Energy still had some research programs going, and I don’t want to slight anyone who was in one of those things. But they stopped building plants. When you stop building plants, it makes it very hard for companies to justify the enormous number of engineers it takes.”

“The thing that struck me the first time we went to China, in particular, is they assigned an awful lot of people to the problem,” said Charles Forsberg, a research scientist at MIT. “And if you assign several hundred engineers to the problem you will learn very, very rapidly.” Forsberg spent his early career as a researcher at ORNL before moving to MIT, where he is overseeing the construction of a molten-salt loop that will run along the side of the campus’s research reactor. He is also one of three engineers who, in 2002, hashed out the concept for a fluoride salt-cooled high-temperature reactor, or FHR. That involved taking Weinberg’s molten-salt reactor and swapping the liquid-fuel loop for a more conventional core design, while still using molten salt as a coolant. This change simplified the most vexing problems, of corrosion and containment, while preserving the high process heat that molten salt makes possible. The FHR has played a significant role in rekindling interest in molten salt for fission reactors in the US — which is the reason that Forsberg initially travelled to China to meet with the SINAP team.

Forsberg’s travel, and the relationship that he developed with Xu Hongjie and other researchers at SINAP, took place at the outset of a relatively recent period of collaboration between the US and China. The partnership was formed under the framework of a 2011 “memorandum of understanding” between the DOE and the Chinese Academy of Sciences, which provided for coöperation on nuclear technologies. That agreement was based on a previous agreement, from 2006, which had cleared the way for US nuclear firms to sell reactors to China. Both stemmed from the desire of each country to leverage the other to revamp its own nuclear industry.

China had only a handful of reactors in the early 2000’s, but in 2007 its planners had vowed to massively increase nuclear-energy production by 2020. That meant building something like 40 new reactors in about 15 years — a pace and scale only matched by the US nuclear industry in the 20th century. To meet that goal, China intended to buy the first fleet of new reactors from foreign companies, under contracts that required significant technology transfer. Although this now looks like a mixed bargain, at the time, the US nuclear industry was only too happy to take it. The industry had just weathered a quarter century of effectively zero domestic demand for new reactors, and had hundreds of experts unable to put their skills to use. These were “a bunch of old Navy nuke guys, or guys that studied nuclear engineering forty years ago, who knew a ton about aging management and cracking piping and corroding pumps and things like that,” said David Fishman, then a partner at a boutique China-based nuclear consultancy. “They were just so pleased to come over and find a young, eager market and industry that was planning to build dozens of reactors.”

US-China coöperation on molten-salt research proceeded under conditions not so different from the commercial melee. Forsberg and his collaborators — Per Peterson, a nuclear engineering professor at Berkeley, and Paul Pickard, formerly of Sandia National Laboratories — had pursued their design through academia for years, using oil or water to simulate molten salt, which is expensive and difficult to acquire in the US. Then, in 2011, they were awarded

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Byron Wan

@Byron_Wan

Dec 2, 2025

Wendy Mao (毛立文), Stanford’s Earth Sciences Chair and Deputy Director of Stanford’s Institute for Materials and Energy Sciences at SLAC, has co-authored over 50 publications, trained 5 employees, and maintained a visiting scholar position at 🇨🇳 HPSTAR, an “alias” for China's nuclear weapons program.

In 2020, the 🇨🇳 Center for High Pressure Science and Technology, or HPSTAR, was added to 🇺🇸 Department of Commerce's Entity List, which identifies organizations that pose a significant risk to national security. Since its 2020 Entity List designation, Mao has co-authoredat least 12 peer-reviewed papers with HPSTAR.

The US Entity List describes HPSTAR as an organization “owned by, operated by, or directly affiliated with the Chinese Academy of Engineering Physics (CAEP), which is the technology complex responsible for the research, development and testing of China's nuclear weapons and has been on the Entity List under the destination of China since June 30, 1997.”

According to Canada's 2024 Named Research Organizations List, HPSTAR is an “alias” for the institution behind China’s nuclear weapons program.

HPSTAR studies how materials behave under extreme pressures and temperatures using diamond-anvil cells, synchrotron beams, and X-ray diffraction. Mao is a leading US researcher in this very field.

"It is true that high-pressure experiments are used by scientists working on the domain of nuclear weapons. If anyone is using the diamond anvil cell or shock waves to study materials relevant to nuclear weapons, that's highly sensitive. If those same methods are then applied to sensitive nuclear materials, the combination of these kinds of experiments with these materials starts raising eyebrows."

Both Mao and HPSTAR extensively use diamond anvil cells and shock waves to study materials.

Mao and HPSTAR’s public research papers do not directly involve weapons testing, design, or development. However, these precise high-pressure measurements and theoretical knowledge are the necessary foundations of modern nuclear and advanced weapon design, where accurate modeling of materials under detonation-level conditions is critical.

Over the past two decades, Mao has co-authored at least 50 publications with HPSTAR. Funding acknowledgments show that Wendy Mao and HPSTAR co-authored research financed by US government agencies including DOE (including the National Nuclear Security Administration [NNSA], Argonne National Laboratory, Lawrence Berkeley National Laboratory, Oak Ridge National Laboratory, and Brookhaven National Laboratory); DARPA; DOD; NSF; NIH; ARO; NASA.

Mao has trained at least five 🇨🇳 HPSTAR employees as PhD students in her Stanford and SLAC labs. At least one HPSTAR postdoctoral researcher simultaneously worked on DOE, NNSA, and DARPA-funded research at SLAC.

For example, one of Mao’s current PhD students worked at HPSTAR for three years, from 2015 to 2018, receiving an MS in Condensed Matter Physics before joining Stanford as a PhD student in Mao’s lab.

The other four were trained in Mao’s lab and returned to China to work at HPSTAR. These are only the individuals we were able to identify via web and archival searches.

“Mao has trained 5 PhD students affiliated with China’s nuclear weapons program. Stanford should not permit its federally funded research labs to become training grounds for entities affiliated with China’s nuclear program. Mao’s continued and extensive academic collaboration with 🇨🇳 HPSTAR is adequate grounds for termination.”

Mao served as a visiting scholar at 🇨🇳 HPSTAR’s Shanghai laboratory from at least 2016 to 2019. She also maintains a HPSTAR email address. Her internal Stanford CV and profile list 43 affiliations, but they do not disclose her position at 🇨🇳 HPSTAR.

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stanfordreview.org/investigation-…

“For someone with access to SLAC and other national labs, foreign affiliations must be disclosed under DOE Order 486.1A. Dr. Mao’s undisclosed HPSTAR role and active HPSTAR email raise legitimate concerns about whether federal disclosure rules were followed and whether Stanford had the information needed to manage foreign-influence risk.”

As a professor with appointments at SLAC National Accelerator Laboratory and other sensitive national labs, Mao is subject to this disclosure requirement.

Mao has also co-authored papers in Matter and Radiation at Extremes, a journal owned by CAEP, China’s nuclear development organization. She did so under a 2020 articletitled "Key problems of the four-dimensional Earth system."

The respective organizations responsible for the development of the US and China’s nuclear weapons programs, 🇺🇸 National Nuclear Security Administration and 🇨🇳 CAEP’s National Security Academic Fund, are co-funders for several of Mao’s projects.

China’s nuclear program started the National Security Academic Fund to strengthen “exploratory national security basic scientific research.” According to leaked documents from China’s nuclear program, translated by Georgetown University, “The NSAF Fund has broken new ground for CAEP in attracting technological forces across China to start basic research with the pulling force of national security requirements.”

Mao is listed as a co-author, contributing the aforementioned “national security basic research,” to at least 6 NSAF-funded research projects with HPSTAR collaborators. In funding acknowledgments, HPSTAR is described as an institution “supported by [CAEP’s] NSAF (grant no: U1530402).”

On Nov 23, 2024, Mao was published as a co-author on a paper titled “Iron Bonding with Light Elements: Implications for Planetary Cores Beyond the Binary System.” Wenzhong Wang, from the University of Science and Technology of China, is listed as a collaborator. This paper also acknowledges funding from NASA’s Exoplanet Program.

The Wolf Amendment prohibits the use of NASA grants from collaboration “with institutions of the People’s Republic of China.” According to NASA’s document on the matter, “that means that it's not enough that a NASA grantee simply avoids sending funds to PRC; rather, the grantee may not spend any NASA grant money on any part of a bilateral project with PRC.”

“The Wolf Amendment bars NASA-funded researchers from participating in bilateral projects with Chinese institutions unless a waiver is granted. When a NASA-supported Stanford professor co-authors research with a scientist from a PRC university, the burden is on the institution to show an exemption. Stanford-Mao doesn't have an exemption. Without one, this places the work squarely in a serious Wolf Amendment risk area.”

The Review was unable to verify whether authorization for an exception was granted.

As recently as Sep 12, 2025, Mao published a paper with three HPSTAR co-authors. The research paper featured HPSTAR researchers using cutting-edge equipment at US government laboratories, including X-ray diffraction conducted by the High Pressure Collaborative Access Team at Argonne’s Advanced Photon Source, the Beamline 12.2.2 at Lawrence Berkeley’s Advanced Light Source, and XRD measurements supported by the National Nuclear Security Administration.

“Fundamental research is generally legal, but export controls still apply to hands-on access to sensitive equipment. When export-controlled lasers at SLAC or national laboratories intersect with Stanford HPSTAR-linked students [Mao’s SLAC-trained PhD students] and collaborators, it creates a real risk of transferring controlled US technology and know-how to a PRC-aligned institution.”

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“HPSTAR should not have been granted access to or use of DOE national laboratories. Mao and her collaborators very likely facilitated the use of export-controlled items, including those regulated under the Export Administration Regulations, Category 6, such as sensors and lasers, and Category 3, including electronics and X-ray detectors, for HPSTAR, an institution affiliated with China’s nuclear weapons program. This is a shocking lapse of research security.”

For example, a research project was authored by Wendy Mao, Jin Liu of HPSTAR (formerly a PhD student in Mao’s lab), and Yue Meng of Argonne National Laboratory, among others. The research is “supported by the National Nuclear Security Administration… acknowledges… the use of computing resources from Brookhaven National Laboratory… and X-ray diffraction… conducted at Argonne National Laboratory… HPSTAR is supported by NSAF.” In this case, the NNSA and CAEP’s NSAF are co-funding Chinese “exploratory national security basic scientific research,” using sensitive national laboratories.

“Dr. Mao effectively provides HPSTAR-linked scientists access to US national-lab resources, training, equipment, and funded research, through her positions at Stanford and SLAC. That kind of access is exactly what China’s research system tries to cultivate abroad.”

In 2023, Chairman Mike Lee of the Senate Committee on Energy and Natural Resources wrote a letter warning “Oak Ridge, Los Alamos, and Argonne National Laboratories regarding reports that researchers at all three labs have engaged in research collaborations leveraging… the PRC’s military for federally funded research in sensitive fields.”

Beyond HPSTAR and CAEP, Mao conducted research with the Beijing Institute of Technology and Northwestern Polytechnical University (NWPU). Both institutions are part of China’s Seven Sons of National Defense: key research institutions for the Chinese military. These publications acknowledge co-funding from the DOE and DARPA.

Mao also conducted research with Shanghai Jiao Tong University's National Key Laboratory of Science and Technology on Nano Fabrication, which is also a key Chinese military-designated laboratory.

Wendy Mao’s father, Ho-Kwang Mao (毛河光), was one of the leading US experts in high-pressure physics, a fundamental science behind nuclear weapons development.

He led the NNSA co-sponsored Carnegie-DOE Alliance Center (CDAC). Under his supervision, the center collaborated with and trained NNSA’s staff to ensure nuclear-weapons readiness and stockpile maintenance. Upon recruitment by CAEP in 2012, Ho-Kwang Mao established HPSTAR as a subordinate institution.

This investigation confirms that Wendy Mao has maintained extensive collaboration with organizations advancing China's nuclear program. This raises a fundamental question: how should US institutions respond? What is clear is that the status quo of inaction is untenable.

Over a year ago, documentation of Mao’s collaborations — including her formal role at HPSTAR — was presented to DOE, the FBI, and Stanford University. Yet federal agencies, including the DOE, DoD, DARPA, and multiple national laboratories, continue to fund research that intersects with US-listed entities such as HPSTAR.

To be clear, export-control restrictions, foreign-affiliation disclosure rules, and potential Wolf Amendment issues remain relevant. But the bulk of Mao’s work with HPSTAR appears to fall under the federal definition of fundamental research, meaning the results are “published and shared broadly, with no restrictions for proprietary or national-security reasons.” Under current law, such collaboration with a US-listed entity is generally permitted.

Wendy Mao’s case is not an outlier. It is a revealing example of a much larger institutional problem at Stanford.

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Byron Wan

@Byron_Wan

Jan 22, 2024

https://twitter.com/byron_wan/status/1749349576648380802

Another woman in the video is Adelina Zhang (张宁), who has been serving as hosts in various 🇨🇳 state events in the UK for years. She’s also worked with Newton Leng, the man who yelled at Brendan in the video.

h/t @samdunningo @ftiauto_ptdauto

1/n sohu.com/a/726632135_23…

https://twitter.com/byron_wan/status/1749349576648380802

Adelina Zhang has clearly undergone plastic surgery (left pic: Zhang in 2017)

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The CCP moved fast: they’ve scrubbed the Sohu article in the first tweet in this thread already!

Luckily I’ve archived the same article on another website!!!

3/nweb.archive.org/web/2024012301…

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Byron Wan

@Byron_Wan

Mar 26, 2023

Serbia, Mar 19: 🇨🇳 state-owned China Communications Construction Company demolished the monument to fallen soldiers of the First and Second World Wars in the village of Negrishori during the construction of the Pakovraće - Požega highway.

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The demolition sparked an outrage among veterans’ groups and local residents.

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👇🏻 the monument

In 2021 🇨🇳 China Communications Construction Company promised that the monument would be relocated and the Institute for the Protection of Cultural Monuments in Kraljevo would be informed in advance. But the Chinese company simply demolished it…

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👇🏻 the monument in pieces

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Byron Wan

@Byron_Wan

Mar 24, 2023

🚨 Hong Kong department store Sogo removed LA-based artist Patrick Amadon’s digital artwork No Rioters, an Art Basel exhibit, that contained references to jailed dissidents such as Benny Tai, Joshua Wong and Gwyneth Ho, at the “request” of HK Police.

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Patrick Amadon: “It was too much watching Art Week in Hong Kong pretend the Chinese government didn’t crush a democracy and turn Hong Kong into a vassal surveillance state... because it’s a convenient location for a good market.”

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news.artnet.com/art-world/prot…

“I think it sends the message that money can buy absolution yet again.”

The international community is colluding with the CCP-backed administration to put on an “everything is fine” facade for the police state.

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apnews.com/article/hong-k…

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Byron Wan

@Byron_Wan

Feb 8, 2023

twitter.com/i/web/status/1…

Tina Zhang (张), a 34-year-old 🇨🇳 woman from Qingdao, Shandong province, posted videos on Douyin of her hanging out on Yanaha Island (屋那霸岛) — the biggest uninhabited island in Okinawa — which she claimed she bought in 2020.

Yanaha is just ~60km from 🇺🇸 Kadena Air Base.

1/n twitter.com/i/web/status/1…

The videos went viral on social media and 🇨🇳 news media 红星新闻 ran a story on it on Feb 3…

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🇯🇵 news site Sakisiru broke the news in Japan, causing an uproar and sparking national security concerns. I’m not sure if there’s any coverage in mainstream Japanese media though.

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sakisiru.jp/40825

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