[en] The gravitational field produced by a high-power laser is calculated according to the linearized Einstein field equation in weak field approximation. It is found that when a probe pulse propagates in the above gravitational field, the gravitational Faraday effect and defocusing phenomenon of the probe pulse are induced by the gradient of the energy density of the high-power laser pulse. The rotating angle of the polarization plane of the probe pulse and the variation of its light intensity are derived. The results are discussed and estimated under the conditions of our present experiment facility. (orig.)

[en] The main contents and innovative characteristics of APl000 document numbering procedure are introduced. Combined with practical engineering, we analyze an issue that part documents or drawings cannot be identified by locator code as long as it involves dual locator codes, which causes the document numbering code may not fully illustrate the document's information. The optimization suggestion and research are put forward. (authors)

[en] The radiation responses of prodenia litura nuclear polyhedrosis viruses(NPV) to gamma-ray and electron-beam have been investigated by measuring survival fraction and electron spin resonances(ESR) of irradiated samples. Ionization radiation can produce long lived free radicals in NPV and its concentration is proportional to dose of radiation. The curves of survival fraction with wither dose of radiation or concentration of free radicals were shouldered. Radiation damage mechanism of NPV have been studied by the correlation between survival fraction, free radical concentration and dose of radiation. It is possible to use ESR method for determining infectivity of NPV instead of biology assay

[en] This paper introduces the basic calculation method of PWR airborne radioactivity concentration, and analyzes the airborne concentration of noble gases, fission products, corrosion products and tritium, during each phase such as normal operation, residual heat removal and RPV opened in terms of relative 1000 MWe PWR's design experiences. Especially, the detailed calculations are provided in that concerning the phenomenon of increased airborne radioactivity concentration during residual heat removal due to the iodine spike by fuel cladding failure and the corrosion products burst by oxidation operation respectively. Finally, this paper describes some improvement suggestions for internal exposure protection and ventilation design based on the tendency of PWR airborne radioactivity concentration during each phase. (authors)

[en] We study some effects when a probe light pulse propagates in the spacetime curved by the gravitational field of high-power laser pulses. The gravitational field produced by a high-power laser is calculated by using the linearized Einstein field equation under the weak field approximation. It is found that the gravitational modification of the photon Berry phase occurs when the probe light pulse transports in a uniform winding fiber in this gravitational background. We also find the gravitational redshifting and defocusing for the probe pulse caused by the gravitational field of the high-power lasers

[en] Cycling performance and thermal stability of spinel LiMn₂O₄ cathode material synthesized by a sol–gel method are improved by surface modification with FeF₃ through chemical deposition method. The phase structures, components and morphologies of pristine and FeF₃-coated LiMn₂O₄ are investigated by X-ray diffraction (XRD), Raman spectroscopy and field emission scanning electron microscopy (FESEM). The cycling performances are thoroughly investigated and compared at room and high temperatures. The FeF₃-coated LiMn₂O₄ electrodes display enhanced cycling stabilities compared with that of pristine LiMn₂O₄. Especially, the 5 wt.% FeF₃-coated LiMn₂O₄ demonstrates the best cycling performance, with the capacity retentions of 68.2% after 200 cycles at room temperature (25 °C) and 61.5% after 100 cycles at elevated temperature (55 °C), much better than those of the pristine materials, 49.8 and 40.2%. Cyclic voltammetry (CV) confirms that FeF₃ modification layer improves the structure stability of LiMn₂O₄. Electrochemical impedance spectroscopy (EIS) data illustrate that FeF₃ coating can suppress the fast growth of undesirable solid electrolyte interfacial (SEI) film. Differential scanning calorimetry (DSC) tests show that the existence of FeF₃ helps to enhance the thermal stability of LiMn₂O₄ cathode

[en] The continuous phase transformation from the layered structure to the spinel-like phase seriously degrades the electrochemical properties of Li-rich layered oxides in Lithium-ion batteries. Herein, heterostructured Li-rich cathode materials Li[Li_0.2Ni_0.17Co_0.07Mn_0.56]O₂ in conjunction with different contents of Zr-containing phosphate (ZCP) coating layers were prepared. The structural and electrochemical characterizations reveal that the ZCP surface layer, which not only prevents electrolyte from eroding the Li-rich core and thus suppressing the fast growth of solid electrolyte interface film and charge transfer resistance on the surface of oxide particles, but also enhances the structural and thermal stabilities of the electrode. As a result, the 3 wt.% coated sample delivers an initial discharge capacity of 216 mAh g⁻¹ with a coulombic efficiency of 80%, compared to 202 mAh g⁻¹ and 71%, respectively, for the bare sample. Particularly, the coated sample demonstrates excellent cycling stability with a capacity retention of 91% within 100 cycles, and higher thermal stability.

[en] Highlights: •Hydrothermal method was firstly utilized to prepare Si/TiO₂ composite. •The Si/TiO₂ composite demonstrates a high reversible capacity after 50 cycles. •TiO₂ serves not only as buffer, but also contributes capacity in repeated cycling. -- Abstract: Si/TiO₂ composites as anode material for lithium ion batteries are synthesized by a simple hydrothermal method. X-ray diffraction, inductively coupled plasma and field-emission scanning electron microscopy are used to determine their phase structures, components and surface morphologies. The electrochemical properties of Si, TiO₂ and Si/TiO₂ composites are investigated and compared by galvanostatic cycling measurements, which exhibits the discharge capacities of 4, 121 and 395 mA h g⁻¹ at 0.1 C after 50 cycles, respectively. Cyclic voltammogram measurements are carried out to further clarify the origin of excellent electrochemical performances of the Si/TiO₂ composite. Surface morphologies of electrode plates after 10 cycles show that the Si/TiO₂ composite electrode has more structural retention compared with its Si counterpart. All the experimental observations indicate that the performance improvement of Si/TiO₂ composites could be attributed to TiO₂ which suppresses the volume change of Si particles. On the other hand, TiO₂ also contributes electrochemical activity in repeated cycling with relatively stable structure

[en] Highlights: • Pineapple-structured Si/TiO₂ composite was firstly synthesized by a simple sol–gel method. • Pineapple-structured Si/TiO₂ composite exhibits the best cycling stability. • TiO₂ layer not only effectively inhibits the volume change of Si, but also contributes its electrochemical activity. - Abstract: Nanoscaled Si is successfully wrapped with different contents of nano-TiO₂ (the molar ratios of Si/TiO₂ composites are 1:1, 1:2, 1:3, 1:4 and 1:5, respectively) to form a novel pineapple structure. X-ray diffraction (XRD), Raman spectroscopy, X-ray photoelectron spectroscopy (XPS), field emission scanning electron microscopy (FESEM) and high resolution transmission electron microscopy (HRTEM) are utilized to characterize the structure, component, chemical environment and morphology of the composite. The investigation in cycling performances demonstrates that Si/TiO₂ with molar ratio of 1:4 exhibits the best cycling stability, with specific capacity of 593 mA h g⁻¹ after 50 cycles at 0.1 C, much higher than those of the other composites and the pristine material. Cyclic voltammetry (CV) profiles are also measured and compared. It is believed that the outside TiO₂ particles act as buffer against the huge volume change of Si during repeated alloying and de-alloying, which explains the improved electrochemical performances

[en] Several factors can influence the activated charcoal adsorption coefficients of gaseous radwaste treatment by activated charcoal delay beds in nuclear power plants. This paper analyzes the effects of temperature, relative humidity, gases concentration and gases flow rates on the activated charcoal adsorption coefficients (mainly to krypton and xenon) based on the treatment process by activated charcoal delay beds. Especially, the rationality of gaseous radwaste system process parameters in AP1000 nuclear plants has been discussed. There are several factors impacting the selection of activated charcoal such as adsorption capacity, adsorption selectivity and service lifetime. In order to improve the treatment effects of gaseous radwaste process, the gas superficial velocity should be within the range of 0.1 to 0.7 centimeter per second, the temperature of chilled water should be decreased appropriately, the relative humidity of gaseous radwaste should be lowered than 25% and the operational pressure should be increased correctly. (authors)