[en] The Modular High Temperature Gas-Cooled Reactor (HTR) can be used to burn plutonium fuel to reduce Pu stockpiles because of its inherent safety characteristics and ability to burn a variety of fuel mixtures. The equilibrium core is calculated and analyzed for Pu enriched fuel. Fuel spheres with 7 g heavy metal including the civilian grade Pu and thorium are loaded into the reactor. An enrichment of 11% is chosen to provide the desired equilibrium core reactivity. The fuel and moderator temperature coefficients are both negative. The maximum fuel element temperature during normal operation and during a loss of coolant accident is less than 1500 degree C. 92% of ²³⁹Pu will be burnt during normal operation. Therefore, a thorium fuel cycle in the modular HTR is an effective method for burning civilian grade plutonium

[en] The author presents a special container scanner in which the radiation source is a conventional radiography 60Co projector of (100-300) X3.7 1010Bq. With a special sensitive array detector, invented by Institute of Nuclear Energy Technology (INET) of Tsinghua University and other technical innovations, the characteristics of the 60Co scanner qualify it for use in container inspection. Its contrast indicator (CI) and image quality indicator (IQI) for 10 0 mm steel are equal to 0.7% and 2.5%, respectively, and the steel penetration ( SP) is about 240 mm. The 60Co container scanner is much more economical and more reliable than those scanners using an accelerator source. Also, its penetration ability is much better than that of an X-ray machine scanner. The author presents the system design, the main difficulties and their technical solutions, the inspection characteristics and the special features of the 60Co scanner

[en] Some recent experimental and theoretical work on spin-dependent electron-atom and electron-molecule collisions is reviewed. The spin is involved in such collisions by explicit spin-dependent interactions such as the spin-orbit interaction of the continuum electron (Mott scattering) but also by exchange, which, in conjunction with the Pauli principle, gives rise to observable spin exchange effects. We present results for Mn and Na atoms and experiments in which electron dichroism with chiral molecules has been studied

[en] The nuclear heating reactor (NHR) was developed by the Institute of Nuclear Energy Technology (INET), Tsinghua University. The main design features and safety concepts of the NHR-200, the criteria and principles that were followed in licensing the construction permit of the NHR-200 are discussed. Licensing activities and procedures are described. Some of the main licensing safety issues including accident analysis, secondary containment design, the requirements for the Diesel generators and the safety classification of systems and components are briefly addressed

[en] The numerical calculations for Am multistage fractional extraction by trialkyl phosphine oxide (TRPO) were verified by a hot test. 1750L/t-U high level waste (HLW) was used as the feed to the TRPO process. The analysis used the simple objective function to minimize the total waste content in the TRPO process streams. Some process parameters were optimized after other parameters were selected. The optimal process parameters for Am extraction by TRPO are: 10 stages for extraction and 2 stages for scrubbing; a flow rate ratio of 0.931 for extraction and 4.42 for scrubbing; nitric acid concentration of 1.35 mol/L for the feed and 0.5 mol/L for the scrubbing solution. Finally, the nitric acid and Am concentration profiles in the optimal TRPO extraction process are given

[en] The thermal transition of bovine pancreatic ribonuclease A (RNase A) was investigated using proton nuclear magnetic resonance (NMR). Significant resonance overlap in the large native protein limits accurate assignments in the ¹H NMR spectrum. This study proposes extending the investigation of large proteins by dynamic analysis. Comparison of the traditional method and the correlation coefficient method suggests successful application of spectrum image analysis in dynamic protein studies by NMR

[en] An attempt is made to investigate the ability of the revised K-FIX code to the solution to natural convection. The new experimental data of the benchmark problem of the IAEA coordinated research program (CRP-3) on heat transport and after heat removal for GCRs under accident conditions provided by JAERI are used to calculate nitrogen natural convection in the pressurized vessel and air natural convection in the reactor cavity by using this revised code. Based on analysis, a refined mesh is used to solve the differential equations so as to get more detailed and more accurate result. The obtained velocity profiles are consistent with the result of TRIO-EF code and the result of Bechtel laboratory. It can be drawn that the revised K-FIX code can be used to solve this kind of problems

[en] Myocardial ischemia is the most common and primary cause of myocardium damage. Numerous conventional techniques and methods have been developed for ischemia and reperfusion studies. However, because of damage to the heart sample, most of these techniques can not be used to continuously monitor the full dynamic course of the myocardial metabolic pathway. The nuclear magnetic resonance (NMR) surface coil technique, which overcomes the limitations of conventional instrumentation, can be used to quantitatively study every stage of the perfused heart (especially after perfusion stoppage) continuously, dynamically, and without damage under normal or designed physiological conditions at the molecular level. In this paper, ³¹P-NMR was used to study the effects of ischemia and hypoxia on isolated perfused hearts. The results show that complete hypoxia caused more severe functional damage to the myocardial cells than complete ischemia

[en] Total emission control is an effective pollution control strategy. However, Chinese application of total emission control lacks reasonable and fair methods for optimal treatment cost allocation, a critical issue in total emission control. The author considers four approaches to allocate treatment costs. The first approach is to set up a multiple-objective planning model and to solve the model using the shortest distance ideal point method. The second approach is to define degree of satisfaction for cost allocation results for each polluter and to establish a method based on this concept. The third is to apply bargaining and arbitration theory to develop a model. The fourth is to establish a cooperative N-person game model which can be solved using the Shapley value method, the core method, the Cost Gap Allocation method or the Minimum Costs-Remaining Savings method. These approaches are compared using a practicable case study

[en] The author discusses a scheme of digital Reactor Protection System (RPS). Advanced parallel processing channels, consisting of a microprocessor-based unit and a General Array Logic (GAL)-based unit have been configured in each of the redundant trains to eliminate the risk of common-mode failure of digital RPSs through the way of diversified equipment. Also several digital techniques are also applied to improve the system design. For example, the Voltage/Frequency (V/F) converter is applied to achieve the digitization of the measurement channel. GAL components greatly simplify the hardware circuit design. Two types of communication buses are designed to improve the reliability of data transmission. By all these means, the reliability of RPS can be expected to achieve a great improvement