The superconducting tokamak HT-7U [1] has been designed by the Institute of Plasma Physics since 1998 and will be set up before 2003. The 1.2 MW /2.45 GHz HT-7U LHCD (Lower hybrid current drive) system which being the...The superconducting tokamak HT-7U [1] has been designed by the Institute of Plasma Physics since 1998 and will be set up before 2003. The 1.2 MW /2.45 GHz HT-7U LHCD (Lower hybrid current drive) system which being the most efficient non-induction device can heat the plasma and drive the plasma current has been efficiently in operation 'owl and a particular design of the 2.8 MW/-35 kV high-voltage DC power supply has been already completed and will apply to the klystron of LHCD on HT-7 and the future HT-7U, and the project of the power supply has been examined and approved professionally by an authorized group of high-level specialist in the institute of Plasma Physics. The detailed design of the power supply and the simulation results are referred in the paper.展开更多
Dizziness from preoccupation with the 20th century robbed us of the time to contemplate the 21st century. This is a well-known dictum early back in the 1960s by the late French strategist Raymond Aron. Now the new cen...Dizziness from preoccupation with the 20th century robbed us of the time to contemplate the 21st century. This is a well-known dictum early back in the 1960s by the late French strategist Raymond Aron. Now the new century is upon us. What were believed to be irrelevant then have turned out into hot topics these days. An early warning for the unfolding century, the September 11 events represent but only a展开更多
The effect of diffraction on the ultrasonic velocity measured by the pulse interference method has been investigated in VHF range theoretically and experimentally. Two silicate glasses are taken as the specimens, thei...The effect of diffraction on the ultrasonic velocity measured by the pulse interference method has been investigated in VHF range theoretically and experimentally. Two silicate glasses are taken as the specimens, their frequency dependences of longitudinal velocities are measured in the frequency range of 50-350 MHz, and the phase advances of ultrasonic signals caused by diffraction effect are calculated using A. O. Williams' theoretical expression. For the velocity error due to diffraction effect, the experimental results are in good agreement with the theoretical prediction. It has been shown that the velocity error due to diffraction effect is directly proportional to dθ21 (f)/df, whereθ21 (f) is the phase advances difference between the two partial reflection signals used in velocity measurement and f is the ultrasonic frequency.展开更多
The Traditional Chinese Medicine approach to dealing with A/H1 N1 flu In 2003, an herb called indigowoad root very quickly became popular and sold out of most Chinese drug stores. With Severe Acute Respiratory Syndrom...The Traditional Chinese Medicine approach to dealing with A/H1 N1 flu In 2003, an herb called indigowoad root very quickly became popular and sold out of most Chinese drug stores. With Severe Acute Respiratory Syndrome (SARS)展开更多
Nearly one year after the sweeping Wall Street collapse jolted the world, the picture of the global economy remains muddy and slippery. How are the global bailouts having an effect? What efforts are still needed to he...Nearly one year after the sweeping Wall Street collapse jolted the world, the picture of the global economy remains muddy and slippery. How are the global bailouts having an effect? What efforts are still needed to heal the financial woes? Paul A. Volcker, Former Chairman of the Board of Governors of the U.S. Federal Reserve, gave his answers to these questions at a recent Institute of International Finance (IIF) press conference in Beijing. Edited excerpts of his comments follow.展开更多
The government's latest survey finds that most Chinese enterprises remain upbeat about their future The more stringent macroeconomic adjustment measures China put in place earlier this year appear not to have hind...The government's latest survey finds that most Chinese enterprises remain upbeat about their future The more stringent macroeconomic adjustment measures China put in place earlier this year appear not to have hindered the growth and well-being of the country's enterprises. Most remain positive about the prospects for 2006.展开更多
文摘The superconducting tokamak HT-7U [1] has been designed by the Institute of Plasma Physics since 1998 and will be set up before 2003. The 1.2 MW /2.45 GHz HT-7U LHCD (Lower hybrid current drive) system which being the most efficient non-induction device can heat the plasma and drive the plasma current has been efficiently in operation 'owl and a particular design of the 2.8 MW/-35 kV high-voltage DC power supply has been already completed and will apply to the klystron of LHCD on HT-7 and the future HT-7U, and the project of the power supply has been examined and approved professionally by an authorized group of high-level specialist in the institute of Plasma Physics. The detailed design of the power supply and the simulation results are referred in the paper.
文摘Dizziness from preoccupation with the 20th century robbed us of the time to contemplate the 21st century. This is a well-known dictum early back in the 1960s by the late French strategist Raymond Aron. Now the new century is upon us. What were believed to be irrelevant then have turned out into hot topics these days. An early warning for the unfolding century, the September 11 events represent but only a
文摘The effect of diffraction on the ultrasonic velocity measured by the pulse interference method has been investigated in VHF range theoretically and experimentally. Two silicate glasses are taken as the specimens, their frequency dependences of longitudinal velocities are measured in the frequency range of 50-350 MHz, and the phase advances of ultrasonic signals caused by diffraction effect are calculated using A. O. Williams' theoretical expression. For the velocity error due to diffraction effect, the experimental results are in good agreement with the theoretical prediction. It has been shown that the velocity error due to diffraction effect is directly proportional to dθ21 (f)/df, whereθ21 (f) is the phase advances difference between the two partial reflection signals used in velocity measurement and f is the ultrasonic frequency.
文摘The Traditional Chinese Medicine approach to dealing with A/H1 N1 flu In 2003, an herb called indigowoad root very quickly became popular and sold out of most Chinese drug stores. With Severe Acute Respiratory Syndrome (SARS)
文摘Nearly one year after the sweeping Wall Street collapse jolted the world, the picture of the global economy remains muddy and slippery. How are the global bailouts having an effect? What efforts are still needed to heal the financial woes? Paul A. Volcker, Former Chairman of the Board of Governors of the U.S. Federal Reserve, gave his answers to these questions at a recent Institute of International Finance (IIF) press conference in Beijing. Edited excerpts of his comments follow.
文摘The government's latest survey finds that most Chinese enterprises remain upbeat about their future The more stringent macroeconomic adjustment measures China put in place earlier this year appear not to have hindered the growth and well-being of the country's enterprises. Most remain positive about the prospects for 2006.
