[en] This paper demonstrates the discovery of coal-derived hydrocarbon in Dongsheng area with evidences in several aspects and expounds the relation between uranium mineralization and coal-derived hydrocarbon. The authors indicate that coal-derived hydrocarbon not only provide important reductant to uranium mineralization but also preserve the deposit. This study has supplied an new organic criteria for the uranium exploration and expended the field of organic geochemistry for uranium deposit research. (authors)

[en] Zaohuohao uranium deposit in Inner Mongolia is of sandstone-type formed by the paleo-interlayer oxidation. Organic indicators shew obvious geochemical zones which can be used as location mark of transitional zone. It was considered that the high content of organic matters was caused by the superposition of the sedimentation of organic matters within and outside the transitional zones, which were controlled by lithofacies paleogeography and uranium-organism reaction in the paleo interlayer zone respectively. Organic matters in the transitional zone contains humus, organic clay complex and kerogen. Uranium act as the catalyst to thermal evolution of organic matters. This may cause the high maturation of organic matters in the transitional zone. Zaohuohao Uranium Deposit was the product of the diagenetic evolution. Organic matters of Jurassic coal measure stratum produced rich soluble organic matter and hydrocarbons which participated in all the process of uranium mineralization. This study broadened the research field of organic geologic process of sandstone type uranium deposit. (author)

[en] The specific activity and distribution pattern of ¹³⁷Cs in soils all around the province of Yunnan are reported in this paper, with the primary impact factors discussed. (authors)

[en] Through systematic drill core observation, section contrast and analysis,it is proved that the ore-controlling interlayer oxidation zone of Qianjiadian uranium deposit is mainly composed by the red oxidized sandstone and locally distributed yellow and off-white sandstones. The red sandstone contains charcoal fragments, pyrite, ilmenite, siderite, which have been oxidized intensively, and it can be deduced that their original color was gray and became red due to the oxidization. The distribution of the oxidation zone is mainly controlled by the sedimentary facies,which also controll uranium metallization. The uranium orebodies mainly developed in the thinning or pinch parts of the red oxidation zone in section. On the plans, the uranium mineralization distributes near the front of the red interlayer oxidation zone. (authors)

[en] Rock-Eval pyrolysis is introduced into the research of uranium geology by means of oil-gas geochemical evaluation. Hydrocarbon (oil-gas) components in DS sandstone-type uranium deposit are detected quantitatively. Through analyzing the oil-gas bearing categories of the uranium-bearing sandstones, the internal relationships between the uranium deposit and the oil-gas are revealed. Rock-Eval pyrolysis is an effective method to study the interaction between inorganic and organic matters, and should be extended to the study of sandstone-type uranium deposits. (authors)

[en] Recently, there is a growing Electromagnetic Pulse (EMP) threat caused by North Korea’s nuclear weapons and unmanned aerial vehicles (UAVs). KHNP CRI is currently conducting a research project that will evaluate the safety of domestic nuclear power plants (NPPs) against EMP effects and prepare safety measures to counter vulnerable points. We will instead use simulation tools to evaluate the electromagnetic shielding ability and the conductivity of cables through vulnerable points in NPPs. Through a study of electromagnetic simulation techniques and tools, this paper suggests a simulation method for analysis of EMP effects in operating NPPs. Although 3D tools are relatively accurate, is difficult to use only 3D tools to simulate EMP effects for huge and complex structures such as NPPs. It is more efficient in terms of cost and time to use a 3D tool and an EMT tool for the simulation of such structures. We have compared the advantages and disadvantages of various methods and have selected the most appropriate tools; we will proceed in our next paper with the simulation of EMP effects

[en] The suppresion of the superconducting transition temperature of both the d-wave superconductor with nonmagnetic impurities and the s-wave one with magnetic impurities are described by the Abrikosov-Gor'kov formula. Unfortunately, this leads to a lot of confusion in high T_c superconductor community. We compute here a few physical quantities of these 2 systems, which can discriminate two cases without ambiguity. In particular, the immediate appearance of the gapless behavior is a clear signature of d-wave superconductor, while the persistence of the energy gap is the one of s-wave superconductor. (orig.)

[en] Arrays of ZnO nanorods with different, user-controlled, diameters were formed on Si substrates by 193 nm pulsed laser deposition in a low background pressure of oxygen. The effect of nanorod diameter on the photoluminescence exhibited by these arrays was investigated, as a function of incident ultraviolet (UV, 325 nm) laser intensity. Nanorods with large surface to volume ratios can exhibit high UV (∼380 nm) emission efficiencies, particularly when excited at higher incident intensities. Pre-illumination of such nanorods with 325 nm radiation serves to enhance the UV emission measured at lower incident intensities. These observations are rationalized in terms of photo-induced desorption of surface-bound oxygen, resulting in a quenching of the depletion layer at the ZnO surface. These findings serve to reinforce the potential of ZnO nanostructures for optoelectronic device applications

[en] Objective: To evaluate the possible white matter damage and to define the location of the damage in Alzheimer's disease (AD) with diffusion tensor imaging (DTI). Methods: Twenty-four AD patients and twenty-one age-matched healthy volunteers received conventional and DTI scanning. The ADC and FA of white matter in temporal, parietal, frontal lobe and cingulum were measured respectively and the data underwent postprocessing. Results: FA value of the whiter matter in frontal, parietal, temporal and cingulum in AD patients was 0.37 ± 0.06, 0.32 ±0.05, 0.26 ± 0.03, and 0.47 ± 0.09, respectively, and ADC value was 9.50 e-10 ± 2.02 e-10, 10.55 e-10 ±1.43 e-10, 11.45 e-10 ±0.76 e-10, and 10.10 e-10 ±2.18 e-10, respectively; FA value of the same corresponding regions in control was 0.44 ± 0.06, 0.38 ± 0.05, 0.32 ± 0.05, and 0.56 ± 0.06, respectively, and ADC value was 8.75 e-10 ±1.63 e-10, 9.83 e-10 ±0.99 e-10, 11.13 e-10 ±0.78 e-10, and 8.28 e-10 ±1.65 e-10, respectively. FA value of the whiter matter in frontal, parietal, temporal, lobe and cingulum decreased (P=0.006) and ADC value increased in cingulum white matter (P=0.006) in AD patients. Conclusion: DTI could reveal the damage in white matter of frontal, temporal, parietal lobe and cingulum. It suggested that not only the gray matter is injuried, but also the white matter is abnormal in AD patients. (authors)

[en] The methods and results of the investigation on natural penetrating radiation level in Yunnan Province are presented. 630 25 km x 25 km-grid measuring points were set up uniformly all over the province, with 955 densely measuring points of different types added. The results show that :(1) The area-weighted, population-weighted and point-weighted average value of natural γ radiation dose rate for field is 66.0, 64.8 and 66.7 nGy·h^-1, respectively; (2) The point-weighted average value of natural γ radiation dose rate for road is 63.2 nGy·h^-1; (3) The population-weighted average and point-weighted value of natural γ radiation dose rate inside building is 91.4 and 93.1 nGy·h^-1, respectively; (4) The point-weighted and population-weighted average value of the dose rate inside buildings from cosmic ray is 40.6 and 39.9 nGy·h^-1, and outside buildings is 45.6 and 45.1 nGy·h^-1, respectively; (5) The point-weighted and population-weighted average value of natural penetrating radiation dose rate inside buildings is 133.7 and 131.3 nGy·h^-1, outside buildings is 112.3 and 109.7 nGy·h^-1, respectively; (6) The annual effective dose equivalent from natural γ radiation, cosmic ray and natural penetrating radiation is 0.51, 0.36 and 0.88 mSv, respectively; and correspondingly, the annual collective effective dose equivalent is 1.7, 1.2 and 2.9 x 10⁴ man·Sv, respectively