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[en] Highlights: • The Cu_2O@Cu_7S_4 core-shell crystals maintained the same morphology with template. • The crystals exhibit enhanced photocatalytic activity than the pure Cu_2O crystals. • The photocatalytic activity of different R crystals is diverse from each other. • A possible formation mechanism has been proposed. - Abstract: Uniform and monodispersed Cu_2O@Cu_7S_4 core-shell micro/nanocrystals have been synthesized successfully at room temperature via a simple chemical etching reaction, using Cu_2O as sacrificial template. The structure and properties of the crystals were characterized by X-ray diffraction (XRD), scanning electron microscope (SEM), transmission electron microscopy (TEM), X-ray photoelectron spectra (XPS). The photocatalytic activity of the Cu_2O@Cu_7S_4 crystals was evaluated by photocatalytic decolorization of MeO (methyl orange) aqueous solution at ambient temperature under visible-light irradiation. The results show that the as-prepared Cu_2O@Cu_7S_4 crystals revealed core-shell structure, which maintained the same morphology with corresponding template and were composed of cuboctahedron Cu_7S_4 shell and active Cu_2O core. Due to the unique Cu_2O@Cu_7S_4 core-shell structure, the crystals exhibit enhanced photocatalytic activity than that of the pure Cu_2O crystals, and the photocatalytic activity of different R crystals is diverse from each other. A possible formation mechanism has been proposed.

[en] To evaluate the value of ^99mTc-MIBI imaging in the detection of breast carcinomas and to assess the relationship between the histopathologic features of the lesions and their imaging characteristics, 84 female patients with palpable breast masses underwent ^99mTc-MIBI breast scintigraphy. The early and delay images were acquired at 2∼4, 5, 60 and 120 min after injection of 740∼925 MBq ^99mTc-MIBI intravenously. 37 of the 43 cases of breast carcinomas were detected by ^99mTc-MIBI scintigraphy, meanwhile the histopathologic features of the lesions greatly influenced their imaging characteristics. The diagnostic sensitivity, specificity were 86.05% and 92.68%, respectively. ^99mTc-MIBI breast scintigraphy is useful for differentiating malignancies from benign breast masses, but false negatives may occur in certain lesions with poor conditions of vascularity and cellularity

[en] Graphical abstract: - Highlights: • The stability and reaction mechanism of CuO supported on ZrO_2 were studied by DFT. • ZrO_2 provides a high resistance to CuO sintering. • ZrO_2 promotes the activity of CuO for CO oxidation in fuel reactor. • The energy barriers are low enough for CuO/ZrO_2 oxidation reaction in air reactor. - Abstract: The addition of inert support is important for the Cu-based oxygen carrier used in chemical looping combustion (CLC). The effects of the ZrO_2 support on the stability and reactivity of Cu-based oxygen carrier were investigated using the density functional theory (DFT). First, the sintering inhibition mechanism of ZrO_2 that support active CuO was investigated. The optimized Cu_4O_4/ZrO_2 structure showed a strong interaction occurred between the Cu_4O_4 cluster and ZrO_2(1 0 1) surface. The interaction prevented the migration and agglomeration of CuO. Next, the adsorption of CO on Cu_4O_4/ZrO_2 and the mechanism of the CuO/ZrO_2 reduction by CO were studied. CO mainly chemisorbed on the Cu site and ZrO_2 acted as an electron donor in the adsorption system. The energy barrier of CuO/ZrO_2 reduction by CO (0.79 eV) was much lower than that of the pure CuO cluster (1.44 eV), indicating that ZrO_2 had a positive effect on CuO/ZrO_2 reduction by CO. After CO was oxidized in the fuel reactor, the CuO was reduced into Cu. The adsorption of O_2 on Cu_2/ZrO_2 and the most likely pathway of Cu_2/ZrO_2 oxidation by O_2 were investigated. The adsorption of O_2 was found a strong chemisorption behavior. The energy barriers were low enough for the Cu-based oxygen carrier oxidation reaction.

[en] The GEM is a novel detector with high gain,high time and location resolution. Imitating the structure of the GEM, a thick GEM-like multiplier which has the similar function with that of the GEM is designed and manufactured. The characteristics of the thick GEM-like multiplier increasing electron energy deposition in absorbing medium has been experimentally studied. The results indicate that the energy deposition gain of x-ray photoelectron in medium is apparent, and the maximum energy deposition can increase by more than 40%. Some suggestions of further increasing the energy deposition are given, and the future application of the way of increasing the x-ray photoelectron energy deposition by the thick GEM-like multiplier in hard x-ray imaging is prospected. (authors)

[en] In 2005, Zhang and Wang proposed an improvement signature scheme without using one-way hash function and message redundancy. In this paper, we show that this scheme exits potential safety concerns through the analysis of boolean algebra, such as bitwise exclusive-or, and point out that mapping is not one to one between assembly instructions and machine code actually by means of the analysis of the result of the assembly program segment, and which possibly causes safety problems unknown to the software

[en] A porous carbon with multiple pore size distribution was synthesized, and regarded as a carrier to obtain the sulfur/carbon (S/C) composite via a gas-phase loading method. We proposed this novel gas-phase loading method by using a specially designed fluid-bed reactor to encapsulate and sequester gas-phase sulfur molecules into the porous carbon in current study. The nitrogen Brunauer-Emmett-Teller (BET), scanning electron microscopy (SEM) and X-ray powder diffraction (XRD) characterizations were investigated on both the porous carbon and the sulfur/carbon composite. The results show that the gas-phase loading method contributes to the combination of sulfur molecules and matrix porous carbon. Furthermore, the sulfur/multiple pore size distribution carbon composite based on the gas-phase loading method demonstrate an excellent electrochemical property. The initial specific discharge capacity is 795.0 mAh g"−"1 at 800 mA g"−"1, with a capacity retention of 86.3% after 100 cycles

[en] A measurement system for the radiation damage inside CMOS operational amplifier was described. This system can observe the damage of functional sub-circuits an operational amplifier while measuring the responds of its characteristics, furthermore, the authors can investigate the various influence of the damage of each functional sub-circuits on the degradation of the whole circuit using this system

[en] A measurement system to detect the radiation damage inside CMOS operational amplifier was described. The system can observe the damage of functional sub-circuits in an operational amplifier while measuring the response of its characteristics, furthermore the various influence of the damage of each functional sub-circuits on the degradation of the whole circuit can be investigated using this system

[en] The association between intrinsic noises and deterministic descriptions/properties of the rate equations for chemical reactions is analyzed using the linear noise approximation of the master equation. We illustrate that the effect of intrinsic noise is determined in combination by three components: the system size, the matrix associated with reaction kinetics, and the eigenvalues associated with the system's dissipation. Generally, a more attractive dynamics tends to attenuate the internal fluctuations more significantly because intrinsic noises are inversely proportional to the absolute value of the real part of the eigenvalues. In addition, a higher reaction rate and larger stoichiometry coefficients will give rise to stronger intrinsic noise. (general)