Search Results

You are looking at 1 - 5 of 5 items for

  • Author or Editor: Cheng -Yun Wu x
  • Refine by Access: All Content x
Clear All Modify Search

Abstract  

137mBa has been applied successfully to dynamic studies for diagnosis in nuclear medicine for a long time. A variety of inorganic exchangers have been employed for the separation of137mBa from its parent137Cs. In the present study, cupric cobaltic ferrocyanide and amorphous zirconyl phosphate were synthesized and compared for use in a137Cs/137mBa generator. The results show that the former can adsorb137Cs more efficiently and provide high elution yield of137mBa with greater than 99.99% radionuclide purity. A new generator involving multimillicuries of137mBa, in connection with a computerized detection system, has been constructed.

Restricted access

Abstract  

A novel type of a binary Ga/Ag alloy electrodeposited on silver substrate as a solid target was developed. It was successfully used for the preparation of 68Gc/68Ga generator. The deposition was carried out in an alkali solution containing gallium, silver and certain electrolytes at controlled current and ambient temperature so that the quality of the deposits was proved to be suited for target irradiation. The yield of 68Ge with proton bombardment on this deposits via the 69Ga(p,2n) reaction was assessed. The chemical process for providing millicuries 68Ge/68Ga generator using a generic tin dioxide as an adsorbent was also established. It was revealed from long-term elution tests that approximately 60–70% of 68Ga could be eluted from the generator column with 4 ml of 1.0M HCl per elution, and high radio- and chemical purities of the eluates were quite satisfactory for application purposes.

Restricted access

Abstract  

A chemical process for the separation of147Nd/147Pm from fission products of synthetic radioactive waste solution has been developed. The process includes: (1) denitration, (2) removal of high concentration of uranium by 30% TBP/kerosene extraction, (3) removal of95Nb,103Ru,137Cs and part of90Sr by 50% TBP/dodecane extraction, (4) separation of147Nd/147Pm from part of90Sr and95Zr by oxalic acid precipitation, and (5) removal of144Ce by mixture of 0.4M D2EHPA and 0.2M TBP extraction. Experimental results indicate that the recovery of147Nd/147Pm in the final separated solution is about 90%. The purification of147Nd and147Pm from some other rare earth elements, viz.153Sm,154Eu and144Ce was further investigated by using a Dowex 50W×8 ion-exchanger. Parameters of flow rate, eluent concentration and pH were examined. The results show that the recovery and radionuclide purity of147Nd plus147Pm under the present separation conditions are 77.8% and 98.6% for diethylenetriaminepentaacetic acid (DTPA) and 87.3% and 99.5% for nitrilotriacetic acid (NTA), respectively.

Restricted access
Scientometrics
Authors:
Jun Yuan
,
Wei Yue
,
Cheng Su
,
Zheng Wu
,
Zheng Ma
,
Yun Pan
,
Nan Ma
,
Zhi Hu
,
Fei Shi
,
Zheng Yu
, and
Yi Wu

Abstract  

This research intends to investigate the patent activity on water pollution and treatment in China (1985–2007), and then compares the results with patents data about Triadic patents, South Korea, Brazil and India over the same periods, patents data were collected from Derwent World Patents Index between 1985 and May 2008. For this study, 169,312 patents were chosen and examined. Total volume of patents, technology focus, assignee sector, priority date and the comparison with other countries are analyzed. It is found that patents on water pollution and treatment filed at China have experienced a remarkable increase and the increase rate of patents filed at China change simultaneous with the percentage of domestic applications. However, the number of high quality Triadic patents with priority country as China remains small. Furthermore, in addition to individual patent assignees, both Chinese universities and enterprises also play important roles in patent activity of water pollution and treatment. In addition, the pattern of South Korea’s development can provide short-term implications for China and the regularity in Triadic patents’ development can provide some guidance to China’s long-term development. In contrast, the development pattern of Brazil and India is less influential to China’s development. Furthermore, China’s technology focuses on water pollution and treatment seem to parallel global and triadic patent trends. This research provides a comprehensive picture of China’s innovation capability in the area of water pollution and treatment. It will help China’s local governments to improve their regional S&T capability and will provide support the National Water Pollution Control and Treatment Project in China.

Restricted access

Thermal dissociation reactions and mechanism of complexes of rare earth(iii) nitrates with the crown ether benzo-15-crown-5 were investigated by means of TG-DTG, DSC, DTA and IR technique. The results have shown that the dissociation processes of the complexes consist of several steps, one of which is a fast decomposition reaction. The fast decomposition peak temperatures (DSC) of all the complexes of the lanthanides (except Pm and Tm) decrease regularly with increasing atomic number. Moreover, values of the enthalpy change of desolvation, fast and the fourth step of decomposition and the apparent activation energies of fast and the fourth step of decomposition were obtained.

Restricted access