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It is a commonplace among students of Northeast Asian security issues to regard North Korea as a rogue state, one which operates outside the norms of global society and which presents an ever-present threat to regional security. In this article, however, the authors present an unorthodox line of analysis which attempts to see North Korea as it sees itself: a state whose external support system rapidly and traumatically disappeared a decade ago; a state confronted by hostile neighbors who wish to undermine its regime and who are heavily armed for possible military actions against it; and a state whose limited ability to participate in the global economy is confined to selling abroad for hard currency the few things that it does well: military equipment, including missile technology. Thus viewed, the authors find wanting the policies pursued towards North Korea by the United States, Japan, South Korea, and China. They stipulate a series of precise policy shifts that these four states must undertake to encourage North Korea to play a more active and positive role in building a durable framework for Northeast Asian regional security. [ABSTRACT FROM AUTHOR]

A series of Tb3+-doped Sr2YTaO6 double perovskite phosphors (SYT:Tb3+) were synthesized using a conventional solid-state reaction method. A strong green emission was observed in the SYT:Tb3+ phosphors, and the optimal doping concentration of Tb3+ was confirmed to be 5 mol%. The electric dipole-dipole interaction was ascribed to be the main mechanism for the luminescence concentration quenching. Analysis of the concentration-dependent fluorescence decay confirmed that the self-generated quenching model holds for the dynamic process of Tb3+ decays in SYT. Furthermore, the internal quantum efficiencies, non-radiative transition rates, and energy transfer rates of the 5D4 level for the SYT:Tb3+ samples were estimated, respectively. The luminescence thermal stability of the sample was also evaluated based on the Arrhenius model. The chromaticity shift of the SYT:5 mol% Tb3+ phosphor was examined to be 0.013 when the sample temperature was increased from 303 to 483 K, thus indicating excellent chromaticity shifting resistance under high temperature conditions. Moreover, the Judd-Ofelt parameters were calculated from the emission spectra of SYT:Tb3+ to be Ω2 = 0.29 × 10-20, Ω4 = 0.45 × 10-20, and &@937;6 = 0.72 × 10-20 cm², respectively. The fluorescence branching ratios and radiative transition rates for the 5D4 level were calculated based on the obtained Judd-Ofelt parameters. Finally, a white light-emitting diode (LED) prototype was assembled using a 310 nm LED chip combined with a prepared green SYT:Tb3+ phosphor and two other commercial blue and red phosphors. The obtained warm white light exhibits good chromaticity coordinates (0.32, 0.32) and a high color rendering index of 96.1. Based on the above results, it can be known that the prepared SYT:Tb3+ phosphors have a potential application as green emitting phosphors in white LEDs. [ABSTRACT FROM AUTHOR]

The three-frequency correction method is used to extract the model parameters in a five-element model which includes MOS capacitance C, parallel resistance Rp, interface layer (IL) capacitance Ci, IL resistance Ri, and series resistance Rs. A method for the error analysis of these model parameters has been developed, using error propagation of measured capacitance Cm and resistance Rm. We have applied this error analysis method to a 0.3 mm × 0.3 mm Al/ZrO2/IL/n-Si MOS capacitor with dielectric thickness 35.9 nm. Accumulation capacitances and their errors at various frequency combinations have been calculated to study suitable frequency selection. The errors in the three-frequency correction method depend on selection of the three frequencies (f1 > f2 > f3) and dissipation factor Dm. For large differences between frequencies f1 and f3 (f3/f1 ∼ 0.05– 0.2), the f2 value should be equal to or a little larger than the average value (f3 + f1)/2 to ensure a small error (less than 4%) in spite of large Dm ∼ 0.20–0.31 at f1 = 1.0–1.6 MHz. For three close f1 and f3 (f3/f1 ∼ 0.25–0.6), small ratios for f2/f1 < ∼ 2/3 and f3/f2 < ∼ 2/3 (f3/f1 < 0.44), f2 = (f3 + f1)/2 and small Dm less than ∼0.20 have been suggested to ensure error less than 4%. Considering the error and possible dispersion, the difference between f1 and f3 should be moderate, i.e. f3/f1 = 0.05 ∼ 0.44. For optimal frequency selection, we suggest f3/f1 = ∼0.10 and f2 = (f3 + f1)/2. The frequency selection is not critical for most MOS capacitors, e.g. this sample Al/ZrO2/IL/n-Si capacitor. The three-frequency correction method together with error analysis is effective in extracting accurate accumulation capacitance. [ABSTRACT FROM AUTHOR]

An Al/ZrO2/IL/n-Si (IL: interface layer) MOS capacitor has been fabricated by metal organic decomposition of ZrO2 and thermal deposition Al. We have measured parallel capacitance (Cm) and parallel resistance (Rm) versus bias voltage curves (Cm, Rm–V) at different AC signal frequency (f), and Cm, Rm–f curves at different bias voltage. The curves of Cm, Rm–f measurements show obvious frequency dispersion in the range of 100 kHz–2 MHz. The energy band profile shows that a large voltage is applied on the ZrO2 layer and IL at accumulation, which suggests possible dielectric polarization processes by some traps in ZrO2 and IL. Cm, Rm–f data are used for frequency dispersion analysis. To exclude external frequency dispersion, we have extracted the parameters of C (real MOS capacitance), Rp (parallel resistance), CIL (IL capacitance), RIL (IL resistance) and Rs (Si resistance) in a five-element model by using a three-frequency method. We have analyzed intrinsic frequency dispersion of C, Rp, CIL, RIL and Rs by studying the dielectric characteristics and Si surface layer characteristics. At accumulation, the dispersion of C and Rp is attributed to dielectric polarization such as dipolar orientation and oxide traps. The serious dispersion of CIL and RIL are relative to other dielectric polarization, such as border traps and fixed oxide traps. The dispersion of Rs is mainly attributed to contact capacitance (Cc) and contact resistance (Rc). At depletion and inversion, the frequency dispersion of C, Rp, CIL, RIL, and Rs are mainly attributed to the depletion layer capacitance (CD). The interface trap capacitance (Cit) and interface trap resistance (Rit) are not dominant for the dispersion of C, Rp, CIL, RIL, and Rs. [ABSTRACT FROM AUTHOR]

The aim of this study was to evaluate the effects of niacin in diet on the expression of nitric oxide synthase (NOS) in rat lungs of the animal model of silicosis established by direct tracheal instillation of silica particles into rat lungs surgically. The niacin concen- tration in serum was analyzed by high performance liquid chromatography (HPLC). The expression of inducible nitric oxide synthase (iN- OS) protein in paraffin-embedded lung sections was determined by streptavidin/peroxidase (SP) staining. Quantitative analysis by Image- Pro Plus was also performed on the expression of iNOS. The results showed that niacin concentration in serum of the niacin-treated rats was significantly higher than that in the control and silica-treated rats. After 7 days of silica instillation, iNOS integrated optical density (IOD) in rat lungs and total NOS and iNOS activities in bronchoalveolar lavage fluid (BALF) in silica-treated rats rose by 273420.75, 2.61 units! mL and 1.89 units/mL respectively, when compared with those in the control rats. Niacin treatment significantly reduced silica-induced iNOS IOD in rat lung tissues and total NOS and iNOS activities in BALF supernatant by 248292.35, 1.50 units/ml and 0.91 units nil, respectively, as compared with those in silica-treated rats. Therefore, niacin can effectively attenuate the pathological expression of NOS in rat lung tissues induced by silica particles. [ABSTRACT FROM AUTHOR]

A bienzymatic cascade for selective sulfoxidation is presented. The evolved recombinant peroxygenase from Agrocybe aegeritra catalyses the enantioselective sulfoxidation of thioanisole whereas the choline oxidase from Arthrobacter nicotianae provides the H2O2 necessary via reductive activation of ambient oxygen. The reactions are performed in choline chloride-based deep eutectic solvents serving as co-solvent and stoichiometric reductant at the same time. Very promising product concentrations (up to 15 mM enantiopure sulfoxide) and catalyst performances (turnover numbers of 150,000 and 2100 for the peroxygenase and oxidase, respectively) have been achieved. [ABSTRACT FROM AUTHOR]

Dependence of quasi-particle alignment on proton and neutron numbers has been studied in A = 80 mass region through g-factor measurements by using TMF-IMPAD. The experimental results show that for the nuclides Zr, Zr and Zr with Z = 40 the proton alignment is followed by the neutron alignment in Zr and Zr, while the neutron alignment is followed by the proton alignment in Zr, and for the nuclides Sr, Y, Zr and Nb with N = 44 the proton aligns only in Sr, the proton alignment occurs first that is followed by the neutron alignment in Y and Zr and the neutron alignment is followed by the proton alignment in Nb. Proton and/or neutron alignments lead to different patterns of the g-factor variation with spin. [ABSTRACT FROM AUTHOR]

The g-factors of the magnetic–rotational intra-band states in 85Zr have been measured by the TMF-IMPAD method for the first time. The configuration $\pi \left(g_{9/2}\right)_8^2 \otimes \nu \left( f_{7/2}\right)$ is established for the band. The measured g-factors are in good agreement with those calculated by the semi-classical model. The decrease of both g-factors and shears angles along the band shows that the total angular momentum is generated by the sheras effect of a step-by-step alignment of the valence protons and neutrons. The rapid neutron alignment leads to a decrease of g-factors along the band. The shears angle of the band-head is great than 90°, which implies that the spin-dependent interaction as well as the residul interaction might be involved in the shears mechanism in 85Zr. [ABSTRACT FROM AUTHOR]