[en] Monodispersed calcium carbonate spherical particles with a size of about 1-2 μm could be prepared by a precipitation reaction of sodium carbonate with calcium chloride in the presence of polymaleicanhydride (PMA) or poly (sodium 4-styene-sulfonate) (PSSS) at room temperature. The as-prepared products were characterized with scanning electron microscopy (SEM), X-ray diffraction (XRD) and differential scanning calorimetry-thermogravimetry (DSC-TG). It was found that the acidity of organic macromolecules is an important parameter for the formation of monodispersed CaCO₃ microspheres, the stronger the acidity of organic macromolecules, the greater the adsorption ability to Ca²⁺ ions, the easier the formation of spherical particles and the smaller the size of microspheres

[en] The authors present a fuzzy modeling method using fuzzy neural network with the back-propagation algorithm. The new method can identify the fuzzy model of a nonlinear system automatically. Fuzzy neural network is used to generate fuzzy rules and membership functions. The feasibility and inferential statistics of the method is examined by using numerical data and XOR problem. As an experimental result, the FNN improves accuracy and reliability, saves design time and minimizes system cost of fuzzy design. The FNN can be used for estimation of human injury in nuclear explosions and can be simplified to a rule neural network (RNN), which is used for pole extraction of signal. Preliminary simulation shows that FNN has vast vistas in nuclear monitoring

[en] A method using neural networks about fuzzy modeling to extract fuzzy knowledge is presented. Both constant and parameterized rules are used. The method is demonstrated by examples for effectiveness of acquiring fuzzy knowledge in nuclear monitoring

[en] The authors presents a fuzzy modeling method using fuzzy neural network with the back-propagation algorithm. The new method can identify the fuzzy model of a nonlinear system automatically. Fuzzy neural network is used to generate fuzzy rules and membership functions. The feasibility and inferential statistic of the method is examined by using numerical data and XOR problem. The FNN improves accuracy and reliability, reduces design time and minimizes system cost of fuzzy design. The FNN can be used for estimation of human injury in nuclear explosions and can be simplified to a rule neural network (RNN), which is used for pole extraction of signal. Preliminary simulation show that FNN has vest vistas in nuclear monitoring

[en] When a gamma-ray spectrometer is used to measure a radioactive sample, the radioactivity distribution in samples may affect the detection efficiency. In order to obtain more accurate content of a radioactive nuclide, the influence of the radioactivity distribution in sample should be estimated. The effect of inhomogeneous radioactivity distribution in I-129 transmutation targets on the detection efficiency was examined employing the MCNP5 code. The ratios of the efficiencies in several extreme situations and various assumed distribution to the efficiency in ideal homogenous distribution were calculated at different sample-detector distances. The calculation results shows that the radioactivity inhomogeneity in samples could not be neglected when the abundance of I-129 was measured by a low energy gamma ray spectrometer, even at a large detection distance, and that the effect of axial inhomogeneity on detection efficiency is much more significant than that of radial inhomogeneity. (authors)

[en] Calcium carbonate particles with various shapes were prepared by the reaction of sodium carbonate with calcium chloride in the absence and presence of a polyacrylic acid (PAA) at 25 deg. C and 80 deg. C, respectively. The as-prepared products were characterized with scanning electron microscopy and X-ray diffraction. The effects of pH, temperatures, aging time and concentration of PAA and CaCO₃ on the crystal form and morphologies of the as-prepared CaCO₃ were investigated. The results show that pH, temperatures, concentration of PAA and CaCO₃ are important parameters for the control of morphologies of CaCO₃. Various crystal morphologies of calcite, such as, plates, rhombohedras, rectangles, ellipsoids, cubes, etc. can be obtained depending on the experimental conditions. Especially, the monodispersed cubic calcite particles can be produced by PAA addition at 80 deg. C. Moreover, higher temperature is beneficial to the formation of monodispersed cubic or rectangular calcite particles. This research may provide new insight into the control of morphologies of calcium carbonate and the biomimetic synthesis of novel inorganic materials

[en] The authors developed a method for discrimination between explosions and earthquakes at the zone. Three discriminant are picked out and put into use, i.e. the ratio of max amplitude in P and S (A_p/A_s), the max period in S waves (T_s), and the ratio of local magnitude to local signal duration magnitude (M_L/M_D). Fuzzy pattern recognition method is applied to events identification (include HeiBei events and ShanXi events), and the rates of correct discrimination are all over 90% without exception

[en] Highlights: • Questions about the applicability, technical status, and future of MSW incineration in China are answered. • Comparison involves China, EU, U.S., Japan, South Korea, and Taiwan area. • MSW incineration is not out of date around the world. • The structure of MSW incineration technologies is changing in China. • Perspectives and suggestions are given for the compliance with the emission standard. - Abstract: With the rapid expansion of municipal solid waste (MSW) incineration, the applicability, technical status, and future improvement of MSW incineration attract much attention in China. This paper aims to be a sensible response, with the aid of a comparison between China and some representative developed regions including the EU, the U.S., Japan, South Korea, and Taiwan area. A large number of up-to-date data and information are collected to quantitatively and impartially support the comparison, which covers a wider range of key points including spatial distribution, temporal evolution, technologies, emissions, and perspectives. Analysis results show that MSW incineration is not an outdated choice; however, policy making should prevent the potentially insufficient utilization of MSW incinerators. The structure of MSW incineration technologies is changing in China. The ratio of plants using fluidized bed is decreasing due to various realistic reasons. Decision-makers would select suitable combustion technologies by comprehensive assessments, rather than just by costs. Air pollution control systems are improved with the implementation of China’s new emission standard. However, MSW incineration in China is currently blamed for substandard emissions. The reasons include the particular elemental compositions of Chinese MSW, the lack of operating experience, deficient fund for compliance with the emission standard, and the lack of reliable supervisory measures. Some perspectives and suggestions from both technical and managerial aspects are given for the compliance with the emission standard. This paper can provide strategic enlightenments for MSW management in China and other developing countries.

[en] A novel algorithm for high precision wavefront correction in adaptive optics is proposed in this paper. The process of the new global optimization distribution algorithm (GODA) is detailed described and compared with the existing stochastic parallel perturbation algorithm (SPPA). A deformable mirror (DM) group that could realize the algorithm is also introduced. It is made up of a number of single-actuator DMs. In the DM group, each actuator could have three dimensional movements—deformation in z direction and movements in x and y directions, making the equivalent actuator arrangement alterable. Simulations are carried out to verify the correction ability of the new algorithm realized by DM group. By comparing correction results of conventional DM, DM group with SPPA and GODA, the correction ability of DM group with GODA is proved to be better than SPPA and conventional DM. (paper)

[en] Sodium-24 radionuclide is the major contributions of concentration of total gamma activity in primary system of HFETR. In this paper, the mechanism of sodium-24 nuclide production in primary system is analyzed, and the process of sodium-24 radionuclide with excitation in the core material, release to primary system and primary migration are researched, which is to establish calculation model of sodium-24 radioactive term in primary system of HFETR. The concentration of sodium-24 radionuclide in primary system of HFETR in a power operation is calculated through Monte Carlo N-Particle extended code (MCNPX), and comparing with the actual monitoring results. It turns out that the calculation model of sodium-24 radioactive term is reasonable, and some sensitivity analysis is carried out, which can provide reference for activated term calculation in primary system of the same type of research reactor. (authors)