[en] Room temperature photoluminescence (PL) of boron-doped silica synthesized by a combined sol-gel and heating process has been investigated. The broad PL band has been resolved into three components centered at 3.7, 3.35 and 2.7 eV, which are assigned to non-bridging oxygen hole centers (NBOHC), carbon-related impurity, and two-fold coordinated silicon atoms, respectively. The intensities of the 3.35 and 2.7 eV bands decrease with the heating temperature increasing, due to oxidation of the corresponding luminescent centers. The effect of boron doping on the formation of intrinsic defects in silica is discussed

[en] Nano-scale γ-AgI with grain sizes of 7-9 nm was synthesized by quenching molten AgI in liquid nitrogen (LN). The temperature dependence of ionic conductivity of nano-scale γ-AgI was studied by complex impedance measurement. Linear fit for the log σT vs. 1/T curve revealed that the curve was composed of three segments with different slopes, with two kinks at about 147 deg. C and 223 deg. C. The activation energies for the three segments were calculated to be 0.40, 1.61, and 0.12 eV, respectively. The curve reveals a continuous transition between 147 deg. C and 223 deg. C instead of a break at 147 deg. C that occurring in normal AgI, indicating a change from first-order phase transition to a second-order one after AgI was quenched in LN. The room temperature (RT) conductivity of nano-AgI is about two orders of magnitude larger than that of normal AgI. We suggest that the ionic conduction of nano-AgI within temperature ranges of RT to 147 deg. C, 147-223 deg. C, and above 223 deg. C are controlled by grain boundaries and dislocations induced by quenching, formation and diffusion of Frenkel defects inside the grains, and transport of quasi-liquid silver ion, respectively. The second-order phase transition is attributed to lattice deformation and formation of Frenkel defects

[en] In recent years, with the widespread application of power electronic equipment in various fields of the national economy, the problem of insufficient stability of power electronic equipment has brought a greater negative impact on the application and promotion of new technologies and the development of the national economy. Therefore, to carry out the stability research of power electronic circuits and find suitable methods to reduce the failure rate of power electronic circuits is of great significance for improving the stability of power electronic circuits and promoting the development of power electronic technology and social progress. The purpose of this article is to study the stability of electronic circuits based on the theory of complex neural networks. In this paper, in order to realize the effective use of power grid electricity, during the low period of power consumption, the energy storage battery is operated in the charging state to store the excess energy in the grid; during the peak period of power consumption, the energy storage battery is operated in the discharged state to the load side of the grid powered by. This paper adds a multi-agent system to the power system and uses the linear time-invariant consistency protocol of the multi-agent system to obtain the net active power of the grid. Then, according to the size of the net active power and the working state of the energy storage battery, it is determined whether switch the working status of the energy storage battery. By calculating the changes in the network efficiency value of the circuit weighted network model when the failure rate of each component in the power electronic circuit changes, find the weak points in the power electronic circuit, and prove that the component’s stability to the power electronic circuit is not only related to the failure of the component itself the rate is related to the position of the component in the circuit. Experimental studies have shown that the resistance of current or control signal transmission becomes smaller, especially when the component D1 or D4 is short-circuited, the circuit network efficiency value increases by about 15%. (paper)

[en] Organophosphorus toxicants (OP) include chemical nerve agents and pesticides. The goal of this work was to find out whether an animal could be made resistant to OP toxicity by genetic engineering. The human butyrylcholinesterase (BChE) mutant G117H was chosen for study because it has the unusual ability to hydrolyze OP as well as acetylcholine, and it is resistant to inhibition by OP. Human G117H BChE, under the control of the ROSA26 promoter, was expressed in all tissues of transgenic mice. A stable transgenic mouse line expressed 0.5 μg/ml of human G117H BChE in plasma as well as 2 μg/ml of wild-type mouse BChE. Intestine, kidneys, stomach, lungs, heart, spleen, liver, brain, and muscle expressed 0.6-0.15 μg/g of G117H BChE. Transgenic mice were normal in behavior and fertility. The LD50 dose of echothiophate for wild-type mice was 0.1 mg/kg sc. This dose caused severe cholinergic signs of toxicity and lethality in wild-type mice, but caused no deaths and only mild toxicity in transgenic animals. The mechanism of protection was investigated by measuring acetylcholinesterase (AChE) and BChE activity. It was found that AChE and endogenous BChE were inhibited to the same extent in echothiophate-treated wild type and transgenic mice. This led to the hypothesis that protection against echothiophate toxicity was not explained by hydrolysis of echothiophate. In conclusion, the transgenic G117H BChE mouse demonstrates the factors required to achieve protection from OP toxicity in a vertebrate animal

[en] Optical absorption and room temperature photoluminescence (PL) properties of nanometre AgI-silica composite synthesized by a simple heating-quenching method were investigated. The absorption of quenched AgI-silica was enhanced markedly. Three absorption bands at 440 (2.8 eV), 260 (4.8 eV) and 220 nm (5.6 eV) were observed. The excitonic absorption of AgI showed a red shift of ∼0.11 eV, in contrast to the usually observed blue shift in AgI nanocrystals. Besides two UV emissions from a non-bridging hole centre and E' centre defects formed in silica, the composite exhibited two PL emissions at 2.62 and 2.40 eV. The 2.62 eV PL was ascribed to donor-acceptor recombination of AgI, while the 2.40 eV one may correlate with energy levels induced by the interaction between silica and AgI. The role of silica in improving the PL for nanometre AgI is discussed

[en] Moessbauer measurements of YBa₂Cu_3-xSn_xO_7-y compounds with high Sn concentrations have revealed that the Sn dopants all exist as Sn⁴⁺, with their majority occupying Ba, Y, Cu(2) sites, and only a small part at Cu(1) sites. The amount of Sn at each site varies with Sn content (x). As for supercondcutivity, the sample systems are all with T_c above 77 K. This indicates that the substitutions for the metal ions on Cu(2) and Y sites have small effect on T_c, which strongly supports the concept that Cu-O plane does not predominate the superconductivity

[en] Since there are some weathered accidental inclusion in the sub-grade of a nuclear project in China, an integrative model including the sub-grade, foundation and super-structure were generated using the finite element software ANSYS to assess the influence of these weak rocks. Based on the geological data, the non-homogeneous rock conditions were accurately simulated and the sensitivity analyses to the parameters of weathered accidental inclusion were also carried out. Then the non-homogeneous settlement of the sub-grade rock, the internal force distribution of the raft and super-structure and the structural reinforced design were analyzed in detail, and the results provided a theoretical basis for obtaining the treatment solution of weak rocks. It demonstrated that the weak rocks in the specified limited scale have slight impact on the static capacity of the sub-grade since the surrounding good rocks can support the loads transmitted from the super-structure. The engineering practice also showed the relevant treatment solution is appropriate. (authors)

[en] The room temperature photoluminescence property of ZnO particles embedded in sol-gel silica was investigated. Three ZnO emissions at about 3.25 eV (ultraviolet (UV)), 2.8 eV (blue), and 2.45 eV (green) were observed. The blue and green emissions were ascribed to interstitial zinc and oxygen vacancy defects in ZnO. At heating temperatures above 900 deg. C, the interaction of ZnO with SiO₂ gave rise to Zn₂SiO₄, which enhanced the green emission markedly by limiting the oxidation process of oxygen vacancy. Heating in low oxygen pressure was found to enhance the UV emission substantially. The effects of heating temperature and ambient on blue and green emissions were also discussed

[en] Objective: To investigate the clinical efficacy and prognosis of intensity-modulated radiotherapy (IMRT) combined with chemotherapy for limited-stage small cell lung cancer (LS-SCLC). Methods: A retrospective analysis was performed on the clinical data of 484 LS-SCLC patients treated with chemoradiotherapy in our center from 2006 to 2014. The patients with partial or complete response to IMRT received prophylactic cranial irradiation (PCI). The Kaplan-Meier method was used to calculate survival rates, and the log-rank test and Cox regression were used for univariate and multivariate analyses, respectively. Results: In all the patients, the follow-up rate was 93%; the median overall survival (OS) time was 23.8 months; the 2-, 3-, and 5- year OS rates were 48.7%, 39.8%, and 28.6%, respectively; the median progression-free survival (PFS) time was 14.1 months; the 2-, 3-, and 5- year PFS rates were 34.4%, 30.5%, and 28.3%, respectively. The incidence rates of grade ≥ 3 bone marrow suppression, grade ≥ 2 radiation esophagitis, and grade ≥ 2 radiation pneumonitis were 26.9%, 24.8%, and 18.4%, respectively, in SCLC patients after IMRT. The objective response rate was 84.5%. The univariate analysis showed that age, smoking history, TNM stage, PCI, and the number of chemotherapy cycles before radiotherapy were prognostic factors for OS (P = 0.006, 0.001, 0.047, 0.000, and 0.046). The multivariate analysis showed that smoking history and PCI were independent prognostic factors (P = 0.001 and 0.000). Conclusions: IMRT combined with chemotherapy achieves satisfactory clinical outcomes in the treatment of LS-SCLC. Smoking history and PCI are independent prognostic factors for OS of LS-SCLC patients. (authors)

[en] The SO(3) gauge extension of SM, which is proposed to present a successful explanation for the observed small masses of neutrino and the nearly tri-bimaximal neutrino mixing, predicted the vector-like SO(3) triplet Majorana neutrinos and SU_L(2) double Higgs bosons. In this work we calculate branching ratios of the charged lepton flavor violating decays l_Il-bar_JV induced by these Majorana neutrinos and Higgs bosons. We find that under the model parameters constrained by experimental bounds on the decays Z→l_Il-bar_J, the branching ratio of decays l_I→l_Jγ can be up to 10^-10, which may be accessible at the future experiments. (physics of elementary particles and fields)