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<jats:p>The photoluminescence (PL) properties of blue multiple InGaN/GaN quantum well (BMQW) and green multiple InGaN/GaN quantum well (GMQW) formed on a single sapphire substrate are investigated. The results indicate that the peak energy of GMQW-related emission (<jats:italic>P</jats:italic> <jats:sub>G</jats:sub>) exhibits more significant “S-shaped” dependence on temperature than that of BMQW-related emission (<jats:italic>P</jats:italic> <jats:sub>B</jats:sub>), and the excitation power-dependent carrier-scattering effect is observed only in the <jats:italic>P</jats:italic> <jats:sub>G</jats:sub> emission; the excitation power-dependent total blue-shift (narrowing) of peak position (line-width) for the <jats:italic>P</jats:italic> <jats:sub>G</jats:sub> emission is more significant than that for the <jats:italic>P</jats:italic> <jats:sub>B</jats:sub> emission; the GMQW shows a lower internal quantum efficiency than the BMQW. All of these results can be attributed to the fact that the GMQW has higher indium content than the BMQW due to its lower growth temperature and late growth, and the higher indium content in the GMQW induces a more significant compositional fluctuation, a stronger quantum confined Stark effect, and more non-radiative centers.</jats:p>

<jats:p>The color conversion glass ceramics which were made of borosilicate matrix co-doped (SrBaSm)Si<jats:sub>2</jats:sub>O<jats:sub>2</jats:sub>N<jats:sub>2</jats:sub>: (Eu<jats:sup>3+</jats:sup>Ce<jats:sup>3+</jats:sup>) blue–green phosphors were prepared by two-step method in co-sintering. The change in luminescence properties and the drift of chromaticity coordinates (CIE) of the (SrBaSm)Si<jats:sub>2</jats:sub>O<jats:sub>2</jats:sub>N<jats:sub>2</jats:sub>: (Eu<jats:sup>3+</jats:sup>Ce<jats:sup>3+</jats:sup>) blue–green phosphors and the color conversion glass ceramics were studied in the sintering temperature range from 600 °C to 800 °C. The luminous intensity and internal quantum yield (QY) of the blue–green phosphors and glass ceramics decreased with the sintering temperature increasing. When the sintering temperature increased beyond 750 °C, the phosphors and the color conversion glass ceramics almost had no peak in photoluminescence (PL) and excitation (PLE) spectra. The results showed that the blue–green phosphors had poor thermal stability at higher temperature. The lattice structure of the phosphors was destroyed by the glass matrix and the Ce<jats:sup>3+</jats:sup> in the phosphors was oxidized to Ce<jats:sup>4+</jats:sup>, which further caused a decrease in luminescent properties of the color conversion glass ceramics.</jats:p>

<jats:p>Large-area and flexible reduced graphene oxide (rGO)/Fe<jats:sub>3</jats:sub>O<jats:sub>4</jats:sub> NPs/polyurethane (PU) composite films are fabricated by a facile solution-processable method. The monolayer assembly of Fe<jats:sub>3</jats:sub>O<jats:sub>4</jats:sub> nanoparticles with a high particle-stacking density on the graphene oxide (GO) sheets is achieved by mixing two immiscible solutions of Fe<jats:sub>3</jats:sub>O<jats:sub>4</jats:sub> nanoparticles in hexane and GO in dimethylformide (DMF) by a mild sonication. The x-ray diffraction and Raman spectrum confirm the reduced process of rGO by a simple thermal treatment. The permittivity value of the composite in a frequency range of 0.1 GHz–18 GHz increases with annealing temperature of GO increasing. For 5-wt% rGO/Fe<jats:sub>3</jats:sub>O<jats:sub>4</jats:sub> NPs/PU, the maximum refection loss (RL) of over −35 dB appears at 4.5 GHz when the thickness of film increases to 5 mm. The rGO/Fe<jats:sub>3</jats:sub>O<jats:sub>4</jats:sub> NPs/PU film, exhibiting good electromagnetic properties over GHz frequency range, could be a potential candidate as one of microwave absorption materials in flexible electronic devices.</jats:p>

<jats:p>The principle of dual-energy x-ray grating phase-contrast imaging (DEPCI) is clarified by using the theory of x-ray interference and Fresnel diffraction. A new method of retrieving phase from the two interferograms is proposed for DEPCI, and its feasibility is verified via simulation. Finally, the proposed method applied to DEPCI experiment demonstrates the effectiveness of the method. This paper lays the theoretical foundation for performance optimization of DEPCI and the further integration of DEPCI and computed tomography.</jats:p>

<jats:p>Exploring the emergence and maintenance of cooperation in social dilemma is valuable and it arises considerable concerns of many researchers. In this paper, we propose a mechanism to promote cooperation, called benefit community, in which cooperators linking together form a common benefit community and all their payoffs obtained from game are divided coequally. The robustness of conclusions is tested for the PDG (prisoners’ dilemma game) on square lattice and WS small world network. We find that cooperation can be promoted by this typical mechanism, especially, it can diffuse and prevail more easily and rapidly on the WS small world network than it on the square lattice, even if a big temptation to defect <jats:italic>b</jats:italic>. Our research provides a feasible direction to resolve the social dilemma.</jats:p>

<jats:p>The interaction between extracellular matrices and cancer cells plays an important role in regulating cancer cell behaviors. In this article, we use matrigel to mimic extracellular matrices and investigate experimentally how matrigel influences the shape and dynamics of breast cancer cells (MDA-MB-231-GFP cells). We find that matrigel facilitates cancer cells’ migration and shape deformation. The influences of the matrigel concentration are also reported.</jats:p>

<jats:p>In the field of statistical mechanics and system science, it is acknowledged that the financial crisis has a profound influence on stock market. However, the influence of total asset of enterprise on stock quote was not considered in the previous studies. In this work, a modified cross-correlation matrix that focuses on the influence of total asset on stock quote is introduced into the analysis of the stocks collected from Asian and American stock markets, which is different from the previous studies. The key results are obtained as follows. Firstly, stock is more greatly correlated with big asset than with small asset. Secondly, the higher the correlation coefficient among stocks, the larger the eigenvector is. Thirdly, in different periods, like the pre-subprime crisis period and the peak of subprime crisis period, Asian stock quotes show that the component of the third eigenvector of the cross-correlation matrix decreases with the asset of the enterprise decreasing. Fourthly, by simulating the threshold network, the small network constructed by 10 stocks with large assets can show the large network state constructed by 30 stocks. In this research we intend to fully explain the physical mechanism for understanding the historical correlation between stocks and provide risk control strategies in the future.</jats:p>

<jats:p>The quantum effect of nonlinear co-tunnelling process, which is dependent on atom-pair tunneling and asymmetry of an double-well trap, is studied by using an asymmetrical extended Bose–Hubbard model. Due to the existence of atom-pair tunneling that describes quantum phenomena of ultracold atom-gas clouds in an asymmetrical double-well trap, the asymmetrical extended Bose–Hubbard model is better than the previous Bose–Hubbard model model by comparing with the experimental data cited from the literature. The dependence of dynamics and quantum phase transition on atom-pair tunneling and asymmetry are investigated. Importantly, it shows that the asymmetry of the extended Bose–Hubbard model, corresponding to the bias between double wells, leads to a number of resonance tunneling processes, which tunneling is renamed conditional resonance tunneling, and corrects the atom-number parity effect by controlling the bias between double wells.</jats:p>

<jats:p>We theoretically investigate the exact solutions for generalized parity–time(<jats:inline-formula> <jats:tex-math> <?CDATA ${\mathscr{P}}{\mathscr{T}}$?> </jats:tex-math> <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <mml:mrow> <mml:mi mathvariant="script">P</mml:mi> <mml:mi mathvariant="script">T</mml:mi> </mml:mrow> </mml:math> <jats:inline-graphic xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="cpb_28_11_114202_ieqn3.gif" xlink:type="simple" /> </jats:inline-formula>)-reversal-symmetric Rabi models driven by external fields with monochromatic periodic, linear, and parabolic forms, respectively. The corresponding exact solutions are presented in terms of the confluent Heun equations without any approximation. In principle, the analytic solutions derived here are valid in the whole parameter space. Such a kind of study may offer potential coherent control schemes of the <jats:inline-formula> <jats:tex-math> <?CDATA ${\mathscr{P}}{\mathscr{T}}$?> </jats:tex-math> <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <mml:mrow> <mml:mi mathvariant="script">P</mml:mi> <mml:mi mathvariant="script">T</mml:mi> </mml:mrow> </mml:math> <jats:inline-graphic xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="cpb_28_11_114202_ieqn4.gif" xlink:type="simple" /> </jats:inline-formula>-symmetric two-level systems.</jats:p>

<jats:p>We report on the generation of optical pulses with a nearly one octave-spanning spectrum ranging from 1300 nm to 2500 nm at 1 kHz repetition rate, which are based on intra-pulse difference frequency generation (DFG) in <jats:italic>β</jats:italic>-barium borate crystal (<jats:italic>β</jats:italic>-BBO) and passively carrier-envelope-phase (CEP) stabilized. The DFG is induced by few-cycle pulses initiated from spectral broadening in multiple thin plates driven by a Ti: sapphire chirped-pulse amplifier. Furthermore, a numerical simulation is developed to estimate the conversion efficiency and output spectrum of the DFG. Our results show that the pulses from the DFG have the potential for seeding intense mid-infrared (MIR) laser generation and amplification to study strong-field physics and attosecond science.</jats:p>