Working on his laptop in a cramped spare bedroom, the former schoolteacher ghostwrites for professors, students, government offices - anyone willing to pay his fee, typically about 300 yuan ($45).
"My opinion is that writing papers for someone else is not wrong," he said. "There will always be a time when one needs help from others. Even our great leaders Mao Zedong and Deng Xiaoping needed help writing."
Ghostwriting, plagiarizing or faking results is so rampant in Chinese academia that some experts worry it could hinder China's efforts to become a leader in science.
The communist government views science as critical to China's modernization, and the latest calls for government spending on science and technology to grow by 8 percent to 163 billion yuan ($24 billion) this year.
State-run media recently exulted over reports that China publishes more papers in international journals than any except the U.S. But not all the research stands up to scrutiny. In December, a British journal retracted 70 papers from a Chinese university, all by the same two lead scientists, saying the work had been fabricated.
"Academic fraud, misconduct and ethical violations are very common in China," said professor Rao Yi, dean of the life sciences school at Peking University in the capital. "It is a big problem."
Critics blame weak penalties and a system that bases faculty promotions and bonuses on the number, rather than quality, of papers published.
Dan Ben-Canaan is familiar with plagiarism.
The Israeli professor has been teaching for nine years at Heilongjiang University in the northeastern city of Harbin. A colleague approached him in 2008 for a paper he wrote about the kidnapping and murder of a Jewish musician in Harbin in 1933 during the Japanese occupation.
"He had the audacity to present it as his own paper at a conference that I organized," Ben-Canaan said. "Without any shame!"
In a separate case, he gave material he had written to a researcher at the prestigious Chinese Academy of Social Sciences. He said he was shocked to receive a book by the academic that was mostly a copy and translation of the material Ben-Canaan had provided - without any attribution.
The pressure to publish has created a ghostwriting boom. Nearly 1 billion yuan (more than $145 million) was spent on academic papers in China last year, up fivefold from 2007, a study by Wuhan University professor Shen Yang showed.
One company providing such a service is Lu's, in Liuzhou, a southern industrial city. His Lu Ke Academic Center boasts a network of 20 to 30 graduate students and professors whose specialties range from computer technology to military affairs.
Lu, a 58-year-old Communist Party member, is approached by clients through Internet chat programs. Most are college professors seeking promotions and students seeking help on theses. Once, 10 students from the same college class put in a collective request for him to write their papers, he said.
"Doing everything on your own, independently, should be possible in theory, but in reality it is quite difficult and one will always need some help," Lu said. "This is how I see it. I don't know if it is right."
Even in the business of selling research papers, there are cheats. Among the papers bought and sold in 2007, more than 70 percent were plagiarized, the Wuhan study found.
Early last year, Internet users found that the deputy principal of Anhui Agricultural University had committed plagiarism in as many as 20 papers. The university removed him from his post but allowed him to continue teaching.
In June, the principal of a traditional Chinese medicine university in the city of Guangzhou was accused of plagiarizing at least 40 percent of his doctoral thesis from another paper.
And in March, the state-run China Youth Daily reported a 1997 medical paper had been plagiarized repeatedly over the past decade. At least 25 people from 16 organizations copied from the work, and more doctors are expected to be named as the investigation by two students using plagiarism-detecting software continues, the report said.
Fang Shimin, an independent investigator of fraud, said he and his volunteers expose about a hundred cases every year, publicizing them on a Web site titled "New Threads."
"The most common ones are plagiarism and exaggerating academic achievement," Fang said.
The papers retracted by the British journal came from researchers at Jinggangshan University in southeastern China. The editors are checking other papers from the same institution, and say more retractions are expected. Calls and e-mails sent to Zhong Hua and Liu Tao, the two researchers named as lead authors of the papers, were unanswered. Other researchers contacted at the university too did not respond.
The journal, Acta Crystallographica Section E, publishes discoveries of new crystal structures, much of it from legitimate Chinese research.
"Chinese authors have submitted thousands of high quality structures to Acta E, which represent an important contribution to science," wrote Peter Strickland, managing editor of Journals of the International Union of Crystallography, which owns Acta E, in an e-mail. He said it was the first time fraudulent papers had been found in any of the journals.
Richard P. Suttmeier, an expert in Chinese science policy at the University of Oregon, said the problems can be traced to China's efforts to modernize its science system in the 1980s and early 1990s when research accountability and evaluation were still weak.
In trying to find ready measures of achievement, China emulated Western practices and began to focus on high-quality publications, but with mixed results, he said.
The problems could hurt the country's ambition of becoming a global leader in research, Suttmeier said.
"I suspect there will be less appetite for non-Chinese scientists to collaborate with Chinese colleagues who are operating in a culture of misconduct," he said.
Last month the Education Ministry released guidelines for forming a 35-member watchdog committee. Also, in a faxed reply to questions, it said it has asked universities to get tough.
Rao, the Peking University dean, remains skeptical.
Government ministries are happy to fund research but not to police it, he said. "The authorities don't want to be the bad guy."