[en] Objective: In order to optimize the relevant sections of the Radiation Workers' Personal protective measures, in this research we analyze the results of individual external dose of radiation monitoring of a hospital in Beijing. Methods: The study objective of this research was the radiation workers who work in a certain grade-three general hospital in Beijing. The research objectives were divided into three groups based on the nature of work, interventional radiology, nuclear medicine, radiology diagnosis respectively; and the research objectives were divided into three groups according to division of occupation, specific physicians, technicians, nurses respectively. Thermoluminescence method was adopted in this research to monitor personal dose and compare the results. Results: The Individual Dose Monitoring Results of the hospital was less than 5 mSv, which was below the national standard, and at a low level every year stably. In this research we found statistically significant difference between the interventional radiology group and radiographic diagnosis group, interventional radiology group which was absorbed higher effective dose than radiographic diagnosis group (P < 0.05). There is no statistically significant difference the radiology group and nuclear medicine group, and interventional radiology diagnosis group(P > 0.05). There is no statistically significant among physicians group, technicians group and nurses group (P > 0.05). Conclusion: In this research we found interventional radiology workers absorb relatively higher effective dose and we should enhance self-awareness of occupational radiation protection and health by effective protection education and rules implement. (authors)

No abstract available

[en] As the global first AP1000 nuclear project, Sanmen phase I nuclear project itself has many challenges from design, procurement to construction managements for non practical nuclear project and experience can be referenced. Islands contract pattern was adopted by this project and this contract pattern has its own strength and weakness. Considering the negative influence result from the first unit, this project has the great postpone risk. Shadow management here tries to reduce these risks and enhance the project surveillance and control by the owner to promote the final goal of this project. (authors)

[en] There is plenty of embedment for the electric cabinet in AP1000 PWR nuclear power plant. The embedment is cast-in-place, and the length of embedment is longer as compared with the width and thickness, with high installation accuracy, which is hard to meet the specific tolerance when transport and install the embedment. In order to install the electric cabinet smoothly and achieve the milestone of initial-energization, the control measure for the embedment from fabrication to installation is taken to make sure the installation accuracy. (author)

[en] Based on exergy analysis of charging and discharging processes in a gas-hydrate cool storage system, the formulas for exergy efficiency at the sensible heat transfer stage and the phase change stage corresponding to gas-hydrate charging and discharging processes are obtained. Furthermore, the overall exergy efficiency expressions of charging, discharging processes and the thermodynamic cycle of the gas-hydrate cool storage system are obtained. By using the above expressions, the effects of number of transfer units, the inlet temperatures of the cooling medium and the heating medium on exergy efficiencies of the gas-hydrate cool storage system are emphatically analyzed. The research results can be directly used to evaluate the performance of gas-hydrate cool storage systems and design more efficient energy systems by reducing the sources of inefficiency in gas-hydrate cool storage systems. - Highlights: • Formulas for exergy efficiency at four stages are obtained. • Exergy efficiency expressions of two processes and one cycle are obtained. • Three mainly influencing factors on exergy efficiencies are analyzed. • With increasing the inlet temperature of cooling medium, exergy efficiency increases. • With decreasing the inlet temperature of heating medium, exergy efficiency increases

[en] Highlights: • Investigates match properties of heat or mass transfer processes in HPLD system. • Unmatched coefficient based on entransy dissipation is calculated. • A higher unmatched coefficient means a higher transfer resistance. • Process along the iso-concentration line is better than along the isenthalpic line. • The HPLD system heating the solution for regeneration is recommended. - Abstract: The energy consumption of air-conditioning systems represents a large part of the entire building energy consumption in non-residential buildings. Heat pump-driven liquid desiccant (HPLD) systems have become more and more popular because of their high energy efficiency, and there are many different ways to utilize the condensing heat in this type of air handling device. In the present study, the match properties of the heat and mass transfer processes in the air–desiccant system varying with the inlet air states are investigated, and the unmatched coefficient based on entransy dissipation is adopted to evaluate the performance of HPLD systems. It is demonstrated that the unmatched coefficient of the process along the iso-concentration line is much lower than that along the isenthalpic line. A higher unmatched coefficient means a higher heat or mass transfer resistance caused by the unmatched flow rates or parameters. The HPLD system in which solution is heated for regeneration (Basic Type II) performs much better than the system in which regeneration air is heated (Basic Type I). The unmatched coefficients of the condenser and regenerator decrease from 2.70 and 1.34, respectively, in Basic Type I, to 1.07 and 1.05, respectively, in Basic Type II. Moreover, COP_sys is significantly improved, rising from 1.83 to 4.17

[en] Temperature variation caused by climate change, seasonal variation and geographic locations affects the physicochemical compositions of chromophoric dissolved organic matter (CDOM), resulting in difference in the fates of CDOM-related environmental pollutants. Exploration into the thermal induced structural transition of CDOM can help to better understand their environmental impacts, but information on this aspect is still lacking. Through integrating fluorescence excitation–emission matrix coupled parallel factor analysis with synchronous fluorescence two-dimensional correlation spectroscopy, this study provides an in–depth insight into the temperature–dependent conformational transitions of CDOM and their impact on its hydrophobic interaction with persistent organic pollutants (with phenanthrene as an example) in water. The fluorescence components in CDOM change linearly to water temperature with different extents and different temperature regions. The thermal induced transition priority in CDOM is protein-like component → fulvic-like component → humic-like component. Furthermore, the impact of thermal–induced conformational transition of CDOM on its hydrophobic interaction with phenanthrene is observed and explored. The fluorescence–based analytic results reveal that the conjugation degree of the aromatic groups in the fulvic– and humic–like substances, and the unfolding of the secondary structure in the protein–like substances with aromatic structure, contribute to the conformation variation. This integrated approach jointly enhances the characterization of temperature–dependent conformational variation of CDOM, and provides a promising way to elucidate the environmental behaviours of CDOM. - Highlights: • Thermal-induced structural transition of CDOM was explored. • EEM-PARAFAC and 2DCOS analysis jointly characterized the transition process. • Temperature-dependent hydrophobic interaction of CDOM with PAH was demonstrated. • The integrated approach can help to elucidate the environmental behaviours of CDOM. - Insight into the temperature-dependent conformational transitions of chromophoric DOMs and their impact on their interaction with PoPs is provided.

[en] Highlights: • Sol–gel route is combined with polymerization without using modifier. • Supercritical drying control is the key to obtain super-hydrophobic surfaces. • The whole fabrication is technologically controllable and with low costs. • The production rate is higher than 90%. • The method provides a cost-effective way for industry applications. - Abstract: We successfully synthesized one type of cheap super-hydrophobic hybrid porous materials in a sol–gel process. In this route, hydrophilic polymers and TEOS-base sol are used as precursors, the ultraviolet ray-initiated polymerization and supercritical fluid drying techniques are combined together to fulfill this task. All fabricated samples exhibit lotus-leaf-like surface structures with super-hydrophobicity. The underlying mechanisms are carefully investigated using a field-emission scanning electron microscopy (FESEM) and an X-ray photoelectron spectroscopy (XPS). We found that a well-controlled drying process is crucial to the formation of such super-hydrophobic surfaces. As high as 90% production rate is obtained in our route and thus, it might provide a cost-effective way to produce super-hydrophobic hybrid materials for industry applications

[en] (Sr_1−xCa_x)Nd₂Al₂O₇ (x = 0, 0.1, 0.3, 0.5) ceramics were synthesized by a standard solid state reaction method. Their microwave dielectric properties were investigated together with the structural evolution. X-ray diffraction analysis indicated that Ruddlesden–Popper solid solutions with n = 2 were obtained for all the compositions investigated here. Ca-substitution significantly improved the densification behavior which was associated with the variation of ε_r. More importantly, with increasing the content of Ca, τ_f value was generally improved towards near-zero, and the significantly improved Qf value was obtained at x = 0.5. The stacking fault and distorted lattice fringe in the ceramics were confirmed by TEM observation, and these defects were deeply concerned with the microwave dielectric loss. The best combination of microwave dielectric characteristics was achieved for the composition of x = 0.5: ε_r = 21.1, Qf = 68,200 GHz and τ_f = −0.5 ppm/°C. - Highlights: • The formation of solid solutions with partial Ca substitution for Sr improved the sintering behavior of SrNd₂Al₂O₇ ceramics. • Stacking fault and distorted lattice fringe were confirmed by transmission electron microscopy. • The variation of Qf value was associated with the stacking fault and distorted lattice fringe

[en] In this paper, a new reactor core design is proposed on the basis of a mixed core concept consisting of a thermal zone and a fast zone. The geometric structure of the fuel assembly of the thermal zone is similar to that of a conventional thermal SuperCritical Water-cooled Reactor (SCWR) core with two fuel pin rows between the moderator channels. In spite of the counter-current flow mode, the co-current flow mode is used to simplify the design of the reactor core and the fuel assembly. The water temperature at the exit of the thermal zone is much lower than the water temperature at the outlet of the pressure vessel. This lower temperature reduces the maximum cladding temperature of the thermal zone. Furthermore, due to the high velocity of the fast zone, a wider lattice can be used in the fuel assembly and the nonuniformity of the local heat transfer can be minimized. This mixed core, which combines the merits of some existing thermal SCWR cores and fast SCWR cores, is proposed for further detailed analysis