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Turbulent heat transfer at supercritical pressure is a complex flow phenomenon due to drastic variations in fluid properties near the pseudocritical point. Numerical simulation is an important method to reveal the underlying physics. Currently, low-order numerical methods together with Reynolds-averaged Navier–Stokes equations are the mainstream in which empirical parameters are required, preventing high-fidelity simulations. Through inventing iterative properties updating and density-weighted explicit filtering, this work develops a high-order spectral element solver based on the open-source code Nek5000. By simulating a classical problem of supercritical CO2 flowing in a heated pipe and comparing it with benchmark data, the capability of the solver in direct numerical simulation is validated. Further results suggest lowering the mesh resolution leads to inaccurate predictions of bulk parameters and turbulent statistics. Therefore, filtering-based large eddy simulation (LES) is explored with different filter weights under a coarse mesh. Results show such a method can significantly improve most of the bulk parameters, including the bulk Nusselt number. The optimal filter weight can be determined from a simple optimization problem minimizing the deviation of overall energy conservation. Being high-order and capable of LES without empirical parameter, the current solver is a powerful tool for high-fidelity simulation of turbulent heat transfer at supercritical pressure. [ABSTRACT FROM AUTHOR]

This paper analyzes the characteristics of convective heat transfer of a pulse-heated platinum microwire cooling in CO2 under supercritical pressures based on experimental data. The microwire undergoes a rapid temperature rise of around 664 K within 0.35 ms. An inverse problem is formulated and numerically solved to extract heat transfer data from experimental measurements. In addition, a predictive model for the convective heat transfer coefficient is developed to fully close the equation set. Results are interpreted based on the bulk pressure from 7.38 to 9 MPa and bulk temperature from 295 to 325 K. The convective heat flux of CO2 generally decreases with time, and in the medium-term, the reduction is slightly decelerated owing to buoyancy-driven flows. This demonstrates that high-pressure and low-temperature bulk states generally exert larger convective heat flux to cool the microwire. During the early 10 ms, the time-averaged convective heat flux is of the order of 1 MW/m2, resulting in rapid cooling. This value shows a weak critical enhancement upon crossing the Widom line. During the remaining time, the time-averaged convective heat flux drops to the order of 0.1 MW/m2. Such a drop in heat flux is more obvious in low-bulk-density cases, leading to a relatively long time for sufficient W cooling. [ABSTRACT FROM AUTHOR]

Summary: Pressure swing adsorption (PSA) technology is widely applied to hydrogen purification from mixed gas. This article mainly studies the adsorption dynamics, breakthrough behavior, and temperature profiles of the typical H2/CO2 mixture by activated carbon in the adsorption bed. Based on the Comsol Multiphysics simulation platform, a one‐dimensional multicomponent adsorption, heat and mass transfer modeling is established and validated by published data of H2/CO2 adsorption breakthrough experiments. By comparing the simulated data with the experimental data, it is found that the breakthrough curves are in good agreement, but the temperature profiles are not fit perfectly. After a comprehensive literature review, we found that the heat of adsorption dramatically influences the temperature profiles. The constant heat of adsorption has limitations for modeling breakthrough experiments. A variable heat of adsorption was proposed and applied to improve the temperature profiles. The results show that the variable heat of adsorption can effectively improve the temperature profiles in the gas adsorption process, and it works well for different adsorption temperatures, pressures, and compositions. The variable heat of adsorption instead of the constant heat of adsorption can significantly increase the peak value of the temperature profiles to be more consistent with experimental results. The relative deviations between the simulated and experimental values of the temperature profiles are reduced from 11.42% to 1.47% using the variable heat of adsorption. The simplification form of the Clausius‐Clapeyron equation gives the outline and trend of the correlation between the heat of adsorption and the amount of adsorption for different adsorption temperatures, pressures, and compositions. [ABSTRACT FROM AUTHOR]

This paper reports our experimental findings aimed to understand the importance of compressibility in fluid flow and heat transfer. A platinum microwire of diameter 50 μ m was immersed in a pressure vessel filled with CO 2 at different thermodynamic states around the critical point. The microwire was heated by an electric pulse resulting in a temperature rise of about 667 K during 0.35 ms. The snapshots of CO 2 and the temporal profiles of mean temperature of the microwire were recorded. An explosive breakup of the thermal boundary layer is identified, manifested by a radial spreading fluid layer with a "fluffy" boundary. Since buoyancy can only drive upward motions, such a phenomenon is closely related to compressibility, as a result of complex interactions between thermoacoustic waves and large-density-gradient interfaces. This phenomenon is also responsible for the efficient cooling observed in the first 10 ms because expansion is a cooling process and can also help to evacuate high-temperature fluid. Afterward, the flow exhibits various buoyancy-driven patterns depending on the existence and intensity of surface tension: garland-like cluster, unstable gas column, or normal bubble, followed by a continuously thinning thermal boundary layer. Both the classic and the newly revised thermodynamic phase diagrams are employed and compared in this paper, suggesting the latter is proper and informative. [ABSTRACT FROM AUTHOR]

It is well-known that for the onset of Rayleigh–Bénard (RB) convection in a binary mixture with Soret effect and negative separation ratio, the competitions between temperature and concentration gradients can lead to oscillatory instability. In this paper, through linear stability analysis, a new oscillatory instability is discovered in a binary mixture with positive separation ratio, thanks to the rich physics of a near-critical binary mixture, i.e., a binary mixture under supercritical pressure near the pseudo-critical state. The rich physics includes cross-diffusion effects (i.e., Soret and Dufour effects) and gravity-related effects (i.e., adiabatic temperature gradient and gravitational diffusion). The linear stability problem is governed by six dimensionless parameters, and the positive separation ratio is shown to be general. It is revealed that there are monotonic and oscillatory instabilities, corresponding to the monotonic and oscillatory growths of small perturbations. The conditions for the unexpected oscillatory instability can be interpreted as there are large enough stabilizing concentration gradient, and total diffusivity rate of concentration is less than that of temperature. Under a positive separation ratio, the stabilizing concentration gradient is a result of gravity-related effects. Besides, based on the physical properties of the reference fluid, when oscillatory instability occurs, gravity-related effects have already been the dominant obstacle for instability. This work provides analytical equations to predict the RB instability. More importantly, the newly discovered oscillatory instability overturns the stereotype of the conceptual connection between oscillatory instability and negative separation ratio. [ABSTRACT FROM AUTHOR]

The pursuit of high amplitude and low onset temperature difference is one important topic in thermoacoustic engines. In this paper, a novel standing-wave thermoacoustic engine is constructed working with supercritical CO 2 , whose core components are integrated as a printed circuit heat exchanger (PCHE). Our experimental results confirm that at any location on the resonator, the pressure obeys a cosine law with time, and the whole pressure field exhibits a seesaw-like spatiotemporal behavior. Under a fixed charging mass, the amplitude of pressure oscillation increases with temperature difference, obeying a power law relation. The maximum amplitude achieved in this work is 0.419 MPa at a temperature difference of 151.0 ° C and a mean pressure of 9.621 MPa. Besides, the frequency with an average of 7.6 Hz shows weak variations. The onset temperature difference decreases as the critical pressure is approached, and the minimum value achieved is 14.8 ° C. Moreover, the cooling effect of oscillating CO 2 to the high-temperature portion of the stack is revealed, causing the strongly nonlinear temperature profile along the stack. This paper manifests that supercritical CO 2 and PCHE are highly prospective to be employed in thermoacoustic devices. [Display omitted] • A standing-wave thermoacoustic engine based on PCHE is constructed and tested. • CO 2 at supercritical pressures is employed as the working fluid. • The dimensionless pressure amplitude obeys a power law relation with temperature difference. • Low frequency (averagely 7.6 Hz) and high amplitude (maximum 0.419 MPa) are achieved. • The minimum onset temperature difference is 14.8 ° C. [ABSTRACT FROM AUTHOR]

Tidal waterways perform as the paths through which seawater invades. Their spatial-temporal variation with the shift in Yellow River's route requires the accurate measurement of their status. Visual interpretation for delineating tidal waterways is inefficient due to a substantial amount of work. Buffer analysis provides an alternative to visual interpretation. However, it is difficult to use the buffer distance threshold to identify tidal waterways from other freshwater bodies. In this study, we present a straightforward method for mapping tidal waterways. First, we adopted the normalized difference water body index (NDWI) to extract water bodies. Waterlines were subsequently delineated based on a morphological opening filter with a kernel of 9 × 9. Finally, tidal waterways were mapped based on the proposed topological relation in ArcGIS. We showed the utility of this approach by mapping tidal waterways in the Yellow River Delta, China. The proposed method enables tidal waterways be mapped precisely and was replicable and universal in other similar studies. [ABSTRACT FROM AUTHOR]

In order to improve the quantum yield of red‐emitting CdTe quantum dots (QDs), CdTe:Gd3+ QDs were synthesized by a facile one‐step aqueous method. The composition, morphology, and photoluminescence property of CdTe:Gd3+ QDs were characterized. The results show that the doping of Gd3+ not only leads to a red‐shift in the emission wavelength but also improves the photoluminescence quantum yield (PL QY) of CdTe QDs up to 85.74%. Doping of Gd element causes the Te dangling bond on the surface of CdTe QDs to be destroyed, thus reducing the nonradiative surface recombination, which is considered to be the reason of the increase in PL QY of CdTe QDs. Finally, high color rendition white light was generated from the CdTe:Gd3+ QDs‐assisted phosphor‐converted white light‐emitting diode (WLED). Under operation of 50 mA forward bias current, the fabricated WLED emitted bright warm white light with a high color rendering index of 86, a low correlated color temperature (CCT) of 4020 K, a suitable Commission Internationale de l'Eclairage color coordinates of (0.3651, 0.3223), and an enhanced luminous efficiency of 68.52 lm/W. [ABSTRACT FROM AUTHOR]

Adsorption plays a critical role in surface and interface processes. Fractional surface coverage and adsorption free energy are two essential parameters of molecular adsorption. However, although adsorption at the solid–gas interface has been well‐studied, and some adsorption models were proposed more than a century ago, challenges remain for the experimental investigation of molecular adsorption at the solid–liquid interface. Herein, we report the statistical and quantitative single‐molecule measurement of adsorption at the solid–liquid interface by using the single‐molecule break junction technique. The fractional surface coverage was extracted from the analysis of junction formation probability so that the adsorption free energy could be calculated by referring to the Langmuir isotherm. In the case of three prototypical molecules with terminal methylthio, pyridyl, and amino groups, the adsorption free energies were found to be 32.5, 33.9, and 28.3 kJ mol−1, respectively, which are consistent with DFT calculations. [ABSTRACT FROM AUTHOR]

Adsorption plays a critical role in surface and interface processes. Fractional surface coverage and adsorption free energy are two essential parameters of molecular adsorption. However, although adsorption at the solid–gas interface has been well‐studied, and some adsorption models were proposed more than a century ago, challenges remain for the experimental investigation of molecular adsorption at the solid–liquid interface. Herein, we report the statistical and quantitative single‐molecule measurement of adsorption at the solid–liquid interface by using the single‐molecule break junction technique. The fractional surface coverage was extracted from the analysis of junction formation probability so that the adsorption free energy could be calculated by referring to the Langmuir isotherm. In the case of three prototypical molecules with terminal methylthio, pyridyl, and amino groups, the adsorption free energies were found to be 32.5, 33.9, and 28.3 kJ mol−1, respectively, which are consistent with DFT calculations. [ABSTRACT FROM AUTHOR]

• The mass piston effect caused by cross-boundary mass diffusion is newly identified. • A theory is proposed to formulate the mass piston effect on the acoustic timescale. • The behavior of various indicators is presented for C 2 H 6 -CO 2 mixture. • The theory is quite satisfactory by comparing with numerical simulations. In this paper, we study the thermalization process of an enclosed fluid mixture near its liquid-vapor critical point subjected to cross-boundary mass diffusion. We reveal that the mass piston effect , a fast and efficient thermalization phenomenon can take place, as a result of three cooperative or competing mechanisms: the boundary velocity, the Dufour effect, and the concentration variation. We propose a theory to formulate the mass piston effect on the acoustic timescale, including the amplitudes of the acoustic wave, the wave's propagation, and the energy and temperature efficiencies measuring the performance of the mass piston effect in terms of energy transfer and thermalization. We apply our theory to the representative C 2 H 6 - CO 2 mixture, and present the behavior of various thermodynamic indicators in the critical region over the whole concentration range. We identify that the boundary velocity is the main factor that restricts the efficiency of the thermalization. By comparing with numerical simulations of different initial states and boundary conditions, the theoretical predictions are quite satisfactory. The current work adds a new member to the family of piston effect and gives new insights into the thermalization process in the critical region. [ABSTRACT FROM AUTHOR]

Major differences in beach erosion between two neighboring artificial beaches Xiangluwan Beach (XL beach) and Meiliwan Beach (ML beach) in Zhuhai, China, were studied after Super Typhoon Hato. In this study, a fully nonlinear Boussinesq wave model (FUNWAVE)-Total Variation Diminishing (TVD) was used to distinguish the main impact factors, their relative contributions, and the hydrodynamic mechanisms underlying the different beach responses. Results show that compared to the ML beach, the main reason for the relatively weak erosion on Xiangluwan (XL) beach was the smaller beach berm height (accounting for approximately 75.9% of the erosion response). Regarding the beach with a higher berm, the stronger wave-induced undertow flow, along with the higher sediment concentration, led to a higher offshore sediment transport flux, resulting in more severe erosion relative to the beach with a smaller berm height. The second most important reason explaining the weak erosion on XL beach was the absence of seawalls (accounting for approximately 17.9% of the erosion response). Wave reflection induced by the seawall could cause higher suspended sediment concentration, resulting in a toe scouring near the seawall. The offshore submerged breakwater protected XL beach slightly (accounting for approximately 6.1% of the erosion response). Due to the higher water level induced by storm surge, most of the wave energy could penetrate through the submerged breakwater. The effect of the larger berm width of XL beach was negligible. Compared to the beach with a larger berm width, the erosion/deposition regions in the beach with a narrower berm width showed shoreward migration, without significant changes in the erosion/deposition extent. Despite of this, the larger berm width could reduce the wave energy reaching the shoreline. This study of the storm stability of artificial beaches may be applied to beach restoration design. [ABSTRACT FROM AUTHOR]

The nonlinear oscillatory double-diffusive convection in a thermodynamically near-critical binary fluid layer is investigated to explore the interactions between the piston effect and natural convection in the presence of subcritical bifurcation. The bifurcation diagram of the system is studied. Two subcritical bifurcation branches are depicted, which, together with the trivial branch of pure diffusion, are connected by two hysteresis loops. To understand the role of the piston effect, the Boussinesq counterpart of the near-critical system is considered and compared. Results show that the onset of convection is significantly altered by the piston effect. For the Boussinesq system, the lower boundary layer becomes unstable, brings on finite-amplitude perturbations, and leads to a statistically steady state. However, the near-critical system features a two-stage evolution. In the first stage, the lower boundary layer becomes unstable and then returns to stability. As soon as the temperature field relaxes into the second stage, a change of criterion occurs, and the fluid becomes unstable again. The residual convection motions amplify and finally result in finite-amplitude convection. By this means, the near-critical system becomes insensitive to the existence of the higher equilibrium state in hysteresis loops, and detours relative to the Boussinesq system are observed. This paper gives new insights into the piston effect and its interactions with natural convection from a dynamic system point of view. The conclusions can be extended to other situations where subcritical bifurcations exist. [ABSTRACT FROM AUTHOR]

Increasing salinity has important impacts on biogeochemical processes in estuary wetlands, with the potential to influence the soil respiration, dissolved organic carbon (DOC) and microbial population. However, it is unclear how soil respiration is related to changes in the DOC and microbial community composition with increasing salinity. In this study, soil cores were sampled from a brackish wetland in the Liaohe River estuary and treated by salinity solutions at four levels (fresh water, 3‰, 5‰, and 10‰). Samples of gas, water and soil were collected to determine the respiration rates and microbial community structure of the soil and the DOC leaching from the soil. Compared to the low-salinity treatments (fresh water and 3‰), the high-salinity treatments (5‰ and 10‰) decreased the soil respiration rates by 45–57% and decreased the DOC concentrations by 47–55%. However, no significant differences were observed within the low-salinity treatments nor the high-salinity treatments. There is a positive correlation between the soil respiration rates and DOC concentrations in all treatments, but it does not indicate a genetic cause-effect relationship between them. The microbial community structure varied with the salinity level, with higher β- and δ-Proteobacteria abundance, as well as higher Anaerolineae, and lower Clostridia abundance in the high-salinity treatments. The respiration rates were slightly negatively related to the richness of Proteobacteria and positively related to the richness of Clostridia. This study suggests that there may be a salinity threshold (3–10‰) impacting the organic carbon loss from estuarine brackish wetlands. In addition, the response of soil respiration to increasing salinity may be mainly linked to changes in the microbial community composition rather than changes in the DOC quantity. [ABSTRACT FROM AUTHOR]

We apply equilibrium molecular dynamic simulations for investigating the infinite dilution diffusivity of carbon dioxide in near- and supercritical water (SCW) over the wide temperature ranging from 647 to 973 K at 115, 217, 426 and 663 kg/m3. The diffusion coefficients of SCW and infinite dilution diffusion coefficients (IDDCs) of carbon dioxide are calculated by using the Einstein mean-square displacement method. It is observed that the IDDCs of carbon dioxide in SCW are approximately 1–2 orders of magnitude higher than that in normal water. The analysis of the temperature dependence of the IDDCs of carbon dioxide reveals that they do not conform to the Arrhenius equation. In the near critical region, the IDDCs of carbon dioxide do not exhibit a monotonic change with a variation in temperature, but increase gradually with an increase in the temperature in a region far from the critical state. The anomaly of the temperature dependence of the diffusion of carbon dioxide in SCW can be explained using the microstructure features of the different states of the water. In addition, we observe that the IDDCs of oxygen are slightly larger than those of carbon dioxide under the same conditions. [ABSTRACT FROM AUTHOR]

This article studies the natural convection in near-critical fluids under the Rayleigh-Bénard configuration. The governing equations are non-dimensionalized by using modified scaling factors and five dimensionless parameters are determined, out of which the specific heat ratio γ is investigated thoroughly in terms of its influences on the convection. The governing equations are solved by the finite volume method along with the low Mach number approximation technique. It is revealed that the strength of the piston effect increases with γ. Since the piston effect is more efficient than the convection in terms of heat transfer, as γ is reduced, the relaxation of temperature field is weakened, while the development of convection is enhanced. By comparing the temperature and velocity fields in different cases and analyzing the heat transfer characteristic, we conclude that the final quasi-steady state is almost unaffected. [ABSTRACT FROM AUTHOR]

In this paper, the combination of the deep evidential regression network (DERN) and empirical orthogonal function (EOF) methods, namely, the DERN-EOF method, was proposed to reconstruct the subsurface temperature profiles. Firstly, the DERN method was compared with the previous machine learning methods used in the subsurface temperature field reconstruction, for example the Self-organizing map method. The new network was shown to have certain advantages of higher accuracy and the capability to provide uncertainty estimation, which enables the reconstruction of the subsurface field with higher belief. Analysis of the method performance suggests that the DERN could improve reconstruction accuracy by almost 20% and that the uncertainty statistics agrees well with the data distribution. Then the DERN method combined with the EOF method was used to reconstruct subsurface temperature profiles at a global scale. Results suggest that the reconstruction error in highly dynamic regions, like the Kuroshio Extension and Gulf Stream regions, is significantly higher than that in other regions, and the uncertainties increase with the reconstruction error, suggesting that the proposed method can provide a relatively believable uncertainty estimation. • A new method was proposed to reconstruct ocean subsurface temperature. • The method was based on the deep evidential regression network and the EOF method. • The method could provide uncertainty estimate and higher regression accuracy. • The method performance was studied both at a regional scale and a global scale. [ABSTRACT FROM AUTHOR]

A series of Ca 9 NaZn(PO 4 ) 7 : Eu 2+ /Eu 3+ , Tb 3+ (CNZP: Eu 2+ /Eu 3+ , Tb 3+ ) phosphors were synthesized by the solid-state reaction method. The results of structure refinement indicate that the chemical formula of CNZP can be written as Ca 9.12(5) Zn 0.88(5) Na 1.0(2) (PO 4 ) 7 . Ca 2+ ions fully occupy M1 site and partly occupy M2, M3 and M5 sites. The M4 sites are 100% occupied by Na + ions and Na + ions didn't participate in other sites. Zn 2+ ions partly occupy M2, M3 and M5 sites and the biggest occupation 81(2)% of Zn 2+ was observed for M5 sites. There are both 6-coordinated and 8-corrdinated Ca 2+ and Zn 2+ in CNZP matrix. According to Davolos's theory, we speculated that Eu 3+ ions could substitute both Ca 2+ and Zn 2+ ions in CNZP matrix, while Eu 2+ ions could only replace Ca 2+ ions but not Zn 2+ ions in CNZP host. Eu 3+ ions doped in CNZP matrix only partly were reduced to Eu 2+ state under the preparation conditions. The reaction mechanism was proposed. The emission color of the as-prepared phosphor were tuned from blush-violet to warm-white and yellowish-green by energy transfer of Eu 2+ →Tb 3+ and Tb 3+ →Eu 3+ in CNZP: Eu 2+ /Eu 3+ , Tb 3+ phosphor. The samples showed good thermal stability. All the results imply that CNZP: Eu 2+ /Eu 3+ , Tb 3+ phosphor is a potential color-tunable phosphor candidate for n-UV LEDs. [ABSTRACT FROM AUTHOR]

Here we reported a tunable full-color-emitting Ba 3 P 4 O 13 :Eu 2+ phosphor and the phase selection depending on Eu 2+ doping concentration in two different polymorphic forms of Ba 3 P 4 O 13 . With increasing Eu 2+ doping concentration, the crystal-phase of Ba 3 P 4 O 13 :Eu 2+ phosphor transformed from low-temperature form (low-Ba 3 P 4 O 13 phase) to high-temperature form (high-Ba 3 P 4 O 13 phase) when other synthesis conditions remained constant. The emission from Ba 3 P 4 O 13 :Eu 2+ was strongly related to the specific crystal-phase structure of Ba 3 P 4 O 13 host, and the luminescent colors of Ba 3(1- x ) P 4 O 13 :3 x Eu 2+ were tuned successfully from blue to white and eventually to yellow following the crystal-phase transformation triggered by the Eu 2+ doping. The temperature-dependent photoluminescence properties for the selected Ba 3(1- x ) P 4 O 13 :3 x Eu 2+ phosphors were also investigated. The results suggest low-Ba 3 P 4 O 13 : Eu 2+ phosphor has better thermal stability than high-Ba 3 P 4 O 13 : Eu 2+ phosphor. [ABSTRACT FROM AUTHOR]

The luminescent properties of Eu 2+ ions are strongly influenced by their occupied position in host. In this paper, the luminescent properties of Eu 2+ in BaCdP 2 O 7 : Eu 2+ phosphor were studied from experimental and theoretical aspects. BaCdP 2 O 7 : x Eu 2+ (0.01 ≤ x ≤ 0.06) phosphors, synthesized by a solid-state reaction method under CO atmosphere, exhibited a strong asymmetric blue-green emission at 445 nm. X-ray powder diffraction (XRD) characterization and the Rietveld structural refinements for BaCdP 2 O 7 show that there are a 9-coordinated Ba 2+ lattice site and a 6-coordinated Cd 2+ lattice site in BaCdP 2 O 7 compound. The emission spectrum can be fitted well by two Gaussian peaks at 436 nm and 487 nm, implying that both Ba 2+ and Cd 2+ lattice sites may be occupied by Eu 2+ ions. The calculation using the empirical Van Uitert equation further qualitatively reveals that Eu 2+ occupies both Ba 2+ and Cd 2+ sites, and then emits blue (436 nm) and green (487 nm) light, respectively. Furthermore, above results are also confirmed by the results of the periodic density-functional theory (DFT) and activation energy ( E a ) calculations. Namely, our simulations and experiments simultaneously provide the proof that Eu 2+ can replace both Ba 2+ and Cd 2+ to be a blue-green phosphor. In addition, concentration quenching mechanism, temperature-dependent luminescence and CIE chromaticity coordinate of the BaCdP 2 O 7 : Eu 2+ phosphors were also investigated in this work. All the results indicate that BaCdP 2 O 7 : Eu 2+ phosphor is a potential blue-green phosphor for near ultraviolet-based white-emitting diodes (WLEDs). [ABSTRACT FROM AUTHOR]

Accurate assessment of surface suspended sediment concentration (SSSC) in estuary is essential to address several important issues: erosion, water pollution, human health risks, etc. In this study, an empirical cubic retrieval model was developed for the retrieval of SSSC from Yellow River Estuary. Based on sediments and seawater collected from the Yellow River and southeastern Laizhou Bay, SSSC conditions were reproduced in the laboratory at increasing concentrations within a range common to field observations. Continuous spectrum measurements of the various SSSCs ranging from 1 to 5700 mg/l were carried out using an AvaField-3 spectrometer. The results indicated the good correlation between water SSSC and spectral reflectance ( R ) was obtained in the spectral range of 726-900 nm. At SSSC greater than 2700 mg/L, the 740-900 nm spectral range was less susceptible to the effects of spectral reflectance saturation and more suitable for retrieval of high sediment concentrations. The best correlations were obtained for the reflectance ratio of 820 nm to 490 nm. Informed by the correlation between R and SSSC, a retrieval model was developed ( R = 0.992). The novel cubic model, which used the ratio of a near-infrared (NIR) band (740-900 nm) to a visible band (400-600 nm) as factors, provided robust quantification of high SSSC water samples. Two high SSSC centers, with an order of 10 mg/l, were found in the inversion results around the abandoned Diaokou River mouth, the present Yellow River mouth to the abandoned Qingshuigou River mouth. There was little sediment exchange between the two high SSSC centers due to the directions of the residual currents and vertical mixing. [ABSTRACT FROM AUTHOR]

A dual-emitting phosphor LaOBr: Ce 3+ , Tb 3+ was synthesized, and the corresponding temperature-dependent luminescent properties were systematically investigated. The dual-emitting phosphor exhibits an exactly contrary thermal dependence with respect to the blue emission of the Ce 3+ sensitizer and the green emission of the Tb 3+ activator. The unique energy transfer between Ce 3+ and Tb 3+ enables this luminescent thermometer to be highly temperature-sensitive over a wide temperature range. The fluorescence intensity ratio (FIR) of the blue and green emission bands peaked at 430 and 543 nm is found to have a well-fitted linear relationship with respect to temperature, and the emitting color shifts from blue to green when temperature rises from 273 K to 493 K. The results indicate that Ce 3+ , Tb 3+ co-doped LaOBr phosphor is a potential candidate for a ratiometric and colorimetric luminescent thermometer. [ABSTRACT FROM AUTHOR]

Vibration-based damage detection is a promising structural health monitoring technique for identifying delaminations in composite structures. However, its accuracy may be adversely affected by measurement errors and the discrepancy between the real composite structures and their numerical models. Therefore, it is of critical importance to study the effect of such noise on the prediction accuracy. The ideal way to do this is to analyze the noise effects based on real measurements on large number of specimens. However, evidently, this is cost and time intensive in terms of materials, manufacturing and labor. An alternative way is to add artificial noise to the structural dynamic parameters obtained from numerical model and study diverse cases using this modified numerical data. In this paper, different levels of random artificial noise (1%, 2%, 3% and 5%) are added to the numerical frequencies. In order to prevent any undesirable bias, 10 different sets of random noise, both uniformly and normally distributed, are employed at each noise level for the same frequencies. The frequency shifts from these 10 test cases (at each noise level) were then input into three inverse algorithms, namely graphical technique (GT), surrogate-assisted optimization (SAO) and artificial neural network (ANN), to predict the location, size and interface of delaminations in a composite beam. The predictions were subsequently compared to the actual damage parameters to evaluate the effect of the noise on the prediction accuracies. SAO and ANN were also tested with 100 cases of noise and then further with Monte Carlo simulation with 100,000 samples in ANN to verify the results. Additional noise sensitivity tests were carried out on beams with different delamination sizes and interfaces, to investigate the dependence of noise effect on the damage parameters themselves. Results show that the trends in prediction errors with increasing noise levels become more consistent as the number of samples increased. With 100,000 samples, the predictions by ANN with uniformly distributed noise and Gaussian noise were nearly indistinguishable. Furthermore, prediction accuracies are also affected by the location and size of the delamination. Among the three inverse algorithms, the performance of ANN was found to be less reliable in presence of noise compared to SAO and GT. [ABSTRACT FROM AUTHOR]

A novel blue phosphor KBaYSi 2 O 7 : Ce 3+ was synthesized via a simple solid-state reaction. Rietveld refinement results indicate that this compound crystallizes in a space group of monoclinic P121/n1(14) and Ce 3+ ions are occupying the Y 3+ site. The excitation spectra of KBaYSi 2 O 7 : Ce 3+ phosphor show broad absorption band in range of 250–400 nm, and this phosphor exhibits an intense blue emission centered at 440 nm upon excitation at 365 nm. The centroid shift and crystal field splitting of Ce 3+ 5 d energy levels in KBaYSi 2 O 7 : Ce 3+ was investigated in details. The concentration of Ce 3+ is optimized to be 0.02 and the corresponding critical distance is calculated as 25 Å. The as-prepared phosphor shows good thermal stability (75% at 100 °C), and the internal quantum efficiency is 35%. All the results indicated that KBaYSi 2 O 7 : Ce 3+ may have the potential application as blue-emitting phosphors for near-UV pumped white light-emitting diodes. [ABSTRACT FROM AUTHOR]

Lignin, the most abundant source of renewable aromatic compounds derived from natural lignocellulosic biomass, has great potential for various applications as green materials due to its abundant active groups. However, it is still challenging to quickly construct green polymers with a certain crystallinity by utilizing lignin as a building block. Herein, new green lignin-based covalent organic polymers (LIGOPD-COPs) were one-pot fabricated with water as the reaction solvent and natural lignin as the raw material. Furthermore, by using paraformaldehyde as a protector and modulator, the LIGOPD-COPs prepared under optimized conditions displayed better crystallinity than reported lignin-based polymers, demonstrating the feasibility of preparing lignin-based polymers with improved crystallinity. The improved crystallinity confers LIGOPD-COPs with enhanced application performance, which was demonstrated by their excellent performances in sample treatment of non-targeted food safety analysis. Under optimized conditions, phytochromes, the main interfering matrices, were almost completely removed from different phytochromes-rich vegetables by LIGOPD-COPs, accompanied by "full recovery" of 90 chemical hazards. Green, low-cost, and reusable properties, together with improved crystallinity, will accelerate the industrialization and marketization of lignin-based COPs, and promote their applications in many fields. [Display omitted] • Low-cost porous covalent organic polymers (COPs) are fabricated with natural lignin. • Water is used as reaction solvent for one-pot green synthesis of lignin-based COPs. • The crystallinity of COPs is improved by optimizing synthetic methods and conditions. • Preparing lignin-based polymers with good crystallinity is demonstrated possible. • As-prepared lignin-based COPs work well in the non-targeted food safety analysis. [ABSTRACT FROM AUTHOR]

• The accumulation process of particles under water bearing conditions. • Characteristics of particle accumulation structure and spatial distribution. • Contact characteristics and motion mechanism of particle accumulation bodies. Artificial coastal accumulation is a key link in the reclamation and island-building project. Due to the different particle sizes and contact slope angle of the accumulation, the accumulation body presents complex particle distribution, accumulation form, and internal structure, which affects the overall safety and stability of coastal accumulation. In this paper, the combination of physical model test and numerical simulation analysis is used to study the accumulation process and mechanism of particles as well as the distribution law of particles in the accumulation body. The results showed that the formation of the accumulation is a dynamic process of the combined action of multiple forces. The distribution of the accumulation particles is as follows: fine particles (size) are mainly distributed near the surface and bottom of the slope. Medium particles (size) are uniformly distributed throughout the accumulation, while the coarse particles (size) are mainly distributed in the upper part of the accumulation. Moreover, this distribution pattern became increasingly evident with an increase in slope angle. In particle accumulation, the leading edge particles are propelled by both following particles and finer particles in infiltration gaps, and the particle movement path fluctuates. The average coordination number of particles in each direction and layer of accumulation bodies is positively correlated with the total mass percentage of particles. The maximum coordination number that occurred in the second layer of the X-direction (plane vertical) was 5.45, the first layer of the Z-direction (vertical) was 5.46, and each layer of the Y-direction (horizontal) with symmetric distribution ranged from 5 to 6. The 45° slope had the largest average coordination number in each layer among slopes with different angles. [ABSTRACT FROM AUTHOR]

Coastal areas have become the primary location for nuclear power plant sites due to the convenience of seawater cooling. In China, the diffusion range of thermal discharge water has always been a hot research topic as the basis for sea use areas. The main physical process of heat loss in the numerical simulation of thermal discharge from power plants is heat exchange between the water surface and air. Currently, the methods for calculating this heat loss include the heat flux method and the water surface heat exchange coefficient method. Taking a power plant in Zhejiang as the research object, the MIKE 3 temperature–salinity module (heat flux method) and MIKE ECO Model (water surface heat exchange coefficient method) were used for modeling, and the diffusion of thermal discharge water under different modules was compared and analyzed. The results show that the calculated area of the water temperature rise envelope between the two modules differed significantly under the same conditions. The surface 4 °C temperature rise area, as calculated using ECO Model, was 45.8% smaller than that of the temperature–salinity module. The MIKE 3 temperature–salinity module can simulate the heat accumulation of water under thermal buoyancy, producing a significant thermal stratification phenomenon; the ECO module does not accurately represent the heat exchange process between the water surface and the air, and it does not adequately capture the significant vertical stratification that occurs in real-world scenarios. On this basis, this study not only lays a foundation for further exploring the impact of thermal discharge water from this powerhouse on the structure of surrounding marine biological communities and dissolved oxygen content in water bodies but also provides scientific evidence for the selection of modules when simulating thermal discharge water with the MIKE model. [ABSTRACT FROM AUTHOR]

Based on the theory of flood/ebb asymmetry, the evolution of the geomorphology of representative bays along the southern coast of the Jiaodong Peninsula over the last 40 years was investigated using remote sensing and geographic information system technologies. The results showed that coastal features such as tidal flats and tidal inlets in the bays changed significantly over time. The studied bays are in a ring-shaped geomorphic spatial pattern characterized by shallow water, and they were concentrically ringed by tidal flats and coastal plains before the early 1980s. Later, however, a number of ponds appeared between the coastal plains and tidal flats. The extent of sediment infill for each bay in the 1980s was greater than that in the 1970s. The conversion of flat-inlets and the erosion/deposition change of tidal inlets in these four bays during study period were not synchronized. Each bay was in a state of flood asymmetry, and both the net fine and net coarse sediment deposition took place in the 1970s. From the late 1960s to the early 1980s, Dingzi Bay was characterized by flood asymmetry, and its tidal asymmetry ratio increased. The Jinghai and the Wuleidao bays were in a state of flood asymmetry, and their tidal asymmetry ratios decreased, while Rushan Bay was in a transition state from flood to ebb asymmetry. However, intensive human activities over the last 30 years, especially the construction of coastal ponds, has greatly changed the hydrology and sedimentation of these bays, causing profound changes in geomorphic features; furthermore, these changes have guided the evolutionary process of the bays. Our results suggest that the intensive human activities were key factors that caused changes in the geomorphic evolution of the studied tidal embayments, especially the sudden change from a state of rising flood asymmetry to ebb asymmetry in Dingzi Bay. [ABSTRACT FROM AUTHOR]

A series of new blue-emitting Ca 2(1 − x ) B 2 P 2 O 10 :2 x Eu 2+ ( x = 0.005, 0.010, 0.015, 0.020, 0.025, 0.030 mol%) phosphors were synthesized by the solid state reaction method. The X-ray diffraction (XRD) and scanning electron microscope (SEM) were utilized to characterize the prepared samples. The luminescence properties of the phosphor were studied by excitation and emission spectra. The optimal concentration of Eu 2+ ions in Ca 2 B 2 P 2 O 10 was determined to be x = 0.010 mol%, and the concentration quenching mechanism was studied in detail. These results suggest that Ca 2 B 2 P 2 O 10 :Eu 2+ is a potential blue phosphor for application in WLEDs. [ABSTRACT FROM AUTHOR]

Near the liquid–vapor critical point, strong anomalies in thermodynamic and transport properties induce the piston effect. In the present study, the piston effect is investigated in spherical cells filled with near-critical fluids under zero gravity and small thermal disturbance conditions by numerically solving the thermodynamic model. The results show typical fast-responding bulk temperature, together with high and stable temperature efficiency, which is determined by the particular nature of near-critical fluids. Particularly, a nondimensionalization method is developed to study the influences of the specific heat ratio on the piston effect by simulations for eight near-critical fluids. Results show the specific heat ratio is an efficient indicator, which is negatively correlated with the nondimensional bulk temperature change. The influences of the characteristic length and the boundary conditions on the piston effect are also studied for near-critical carbon dioxide. In addition, some rules concerning the boundary heat flux and the overall heat transfer are also discussed and concluded. [ABSTRACT FROM AUTHOR]

A new adsorbent l -Arg-CS/Fe 3 O 4 was prepared by l -arginine modifying magnetic chitosan for the removal of Cu(II ) ions from aqueous solution. The compositions of l -Arg-CS/Fe 3 O 4 were characterized by infrared (IR) spectroscopy, X-ray diffraction (XRD) analysis and thermogravimetric (TG) analysis, respectively. The surface morphology, particle size and specific surface area were measured on scanning electron microscope (SEM) and micromeritics gas adsorption surface analyzer. The adsorption behavior of l -Arg-CS/Fe 3 O 4 for Cu(II ) were investigated as a function of pH, contact time and initial Cu(II ) concentration. The maximum adsorption capacity for Cu(II ) was 2.13 mmol g −1 at the optimized adsorption conditions, which were pH = 5.5, t = 13 min, C 0 = 4.0 mmol L −1 . The adsorption behavior was evaluated by the analysis of adsorption kinetics. Freundlich and Langmuir isotherm models were used to estimate the adsorption mode. l -Arg-CS/Fe 3 O 4 exhibited high adsorption capability after five regeneration cycles. The adsorption and desorption mechanisms were discussed. The results show that l -Arg-CS/Fe 3 O 4 is a promising adsorbent for removal of Cu(II) from aqueous solutions. [ABSTRACT FROM AUTHOR]

Motivation: Identifying drug-target protein interaction is a crucial step in the process of drug research and development. Wet-lab experiment are laborious, time-consuming and expensive. Hence, there is a strong demand for the development of a novel theoretical method to identify potential interaction between drug and target protein. Results: We use all known proteins and drugs to construct a nodes- and edges-weighted biological relevant interactome network. On the basis of the 'guilt-by-association' principle, novel network topology features are proposed to characterize interaction pairs and random forest algorithm is employed to identify potential drug-protein interaction. Accuracy of 92.53% derived from the 10-fold cross-validation is about 10% higher than that of the existing method. We identify 2272 potential drug-target interactions, some of which are associated with diseases, such as Torg-Winchester syndrome and rhabdomyosarcoma. The proposed method can not only accurately predict the interaction between drug molecule and target protein, but also help disease treatment and drug discovery. [ABSTRACT FROM AUTHOR]

A new porous magnetic chitosan modified by melamine (MA-CS/Fe 3 O 4 ) was synthesized. The compositions and surface topographies were characterized by infrared (IR) spectroscopy, X-ray diffraction (XRD) analysis, thermogravimetric (TG) analysis and scanning electron microscope (SEM), respectively. The results of adsorption kinetics showed the adsorption behavior could be better described by the pseudo-second-order equation ( R > 0.999). The adsorption isotherm was well fitted by the Langmuir equation ( R > 0.999), and the values of separation factors were in the range of 0–1.0. The maximum adsorption capacity for Cu(II) was 2.58 mmol g −1 at the optimal experimental conditions, which were pH = 5.5, t = 25 min, C 0 = 5.0 mmol L −1 . The rate-controlling step was supposed to be chemical adsorption rather than mass transport. The adsorbent still exhibited high adsorption capacity after five regeneration cycles. The adsorption mechanism was due to coordination between Cu(II) and N atoms. [ABSTRACT FROM AUTHOR]

A series of new blue-emitting phosphors Sr 5(1− x ) Cl 0.75 F 0.25 (PO 4 ) 3 : 5 x Eu 2+ ( x = 0.1, 0.2, 0.3, 0.4, 0.5, 0.6 mol%) were synthesized by high-temperature solid state reaction. X-ray powder diffraction (XRD) and field-emission scanning electron microscope (FE-SEM) were used to characterize the crystal structure and micro-morphology of the prepared samples. The photoluminescence properties of these phosphors were investigated by excitation and emission spectra. The effect of Eu 2+ concentration on emission of the phosphor was investigated and the concentration quenching mechanism was discussed in detail. Also, the temperature-dependence luminescence properties of Sr 5 Cl 0.75 F 0.25 (PO 4 ) 3 : Eu 2+ were compared with those of the commercial blue phosphor BaMgAl 10 O 17 : Eu 2+ (BAM). With the increase of temperature, the emission band exhibited blue shift and decreasing emission intensities. The phosphor Sr 5 Cl 0.75 F 0.25 (PO 4 ) 3 : Eu 2+ possesses higher thermal stability than BAM. Furthermore, a bright blue LED was fabricated by combination of n-UV InGaN chip and the phosphor. The results reveal that Sr 5 Cl 0.75 F 0.25 (PO 4 ) 3 : Eu 2+ is a potential blue phosphor for n-UV-pumped white light-emitting-diodes (WLEDs). [ABSTRACT FROM AUTHOR]

Identifying potential drug target proteins is a crucial step in the process of drug discovery and plays a key role in the study of the molecular mechanisms of disease. Based on the fact that the majority of proteins exert their functions through interacting with each other, we propose a method to recognize target proteins by using the human protein–protein interaction network and graph theory. In the network, vertexes and edges are weighted by using the confidence scores of interactions and descriptors of protein primary structure, respectively. The novel network topological features are defined and employed to characterize protein using existing databases. A widely used minimum redundancy maximum relevance and random forests algorithm are utilized to select the optimal feature subset and construct model for the identification of potential drug target proteins at the proteome scale. The accuracies of training set and test set are 89.55% and 85.23%. Using the constructed model, 2127 potential drug target proteins have been recognized and 156 drug target proteins have been validated in the database of drug target. In addition, some new drug target proteins can be considered as targets for treating diseases of mucopolysaccharidosis, non-arteritic anterior ischemic optic neuropathy, Bernard–Soulier syndrome and pseudo-von Willebrand, etc. It is anticipated that the proposed method may became a powerful high-throughput virtual screening tool of drug target. [ABSTRACT FROM AUTHOR]

Identifying and prioritizing disease-related genes are the most important steps for understanding the pathogenesis and discovering the therapeutic targets. The experimental examination of these genes is very expensive and laborious, and usually has a higher false positive rate. Therefore, it is highly desirable to develop computational methods for the identification and prioritization of disease-related genes. In this study, we develop a powerful method to identify and prioritize candidate disease genes. The novel network topological features with local and global information are proposed and adopted to characterize genes. The performance of these novel features is verified based on the 10-fold cross-validation test and leave-one-out cross-validation test. The proposed features are compared with the published features, and fused strategy is investigated by combining the current features with the published features. And, these combination features are also utilized to identify and prioritize Parkinson's disease-related genes. The results indicate that identified genes are highly related to some molecular process and biological function, which provides new clues for researching pathogenesis of Parkinson's disease. The source code of Matlab is freely available on request from the authors. [ABSTRACT FROM AUTHOR]

Background: To investigate the association between the single nucleotide polymorphism (SNP) of hypoxia-inducible factor1 α (HIF-1α) and the susceptibility to cervical spondylotic myelopathy (CSM) and its outcome after surgical treatment. Method: A total of 230 CSM patients and 284 healthy controls were recruited. All patients received anterior cervical corpectomy and fusion (ACF) and were followed for 12 months. The genotypes for two HIF-1α variants (1772C>T and 1790G>A) were determined. Results: In the present study, we found that the HIF-1α polymorphism at 1790G>A significantly affects the susceptibility to CSM and its clinical features, including severity and onset age. In addition, the 1790A>G polymorphism also determines the prognosis of CSM patients after ACF treatment. The GG genotype of 1790G>A polymorphism is associated with a higher risk to develop CSM, higher severity and earlier onset age. More importantly, we found that the 1790G>A polymorphism determines the clinical outcome in CSM patients who underwent ACF treatment. Conclusion: Our findings suggest that the HIF-1α 1790G>A polymorphism is associated with the susceptibility to CSM and can be used as predictor for the clinical outcome in CSM patients receiving ACF treatment. [ABSTRACT FROM AUTHOR]

Abstract: Chain-like systems have been studied by many researchers for their simple structure and wide range of application. Previously, the damage in a chain-like system was detected by the reduction of the mass-normalized stiffness coefficient for certain elements as reported by Nayeri et al. (2008 [16]). However, some shortcomings exist in that approach and for overcoming them; an improved approach is derived and presented in this paper. In our improved approach, the mass normalized stiffness coefficients under two states (baseline state and potentially damaged state) are first estimated by a least square method, then these mass-stiffness coupled coefficients are decoupled to derive stiffness and mass relative change ratios for individual elements. These ratios are assembled in a vector, which is defined as damage indication vector (DIV). Each component in DIV is normalized individually to one to get multiple solutions. These solutions are averaged for estimating relative system changes, while abnormal solutions are discarded. The work of judging a solution as normal or abnormal is done by a cluster analysis algorithm. The most intriguing merit of this improved approach is that the relative stiffness and mass changes, which are coupled in the previous approach, can be separately identified. By this approach, the damage (single or multiple) extent and location can be correctly detected under operational conditions, meanwhile the proposed damage index has a clear physical meaning and is directly related to the stiffness reduction of corresponding structural elements. For illustrating the effectiveness and robustness of the improved approach, numerical simulation of a four floor building was carried out and experimental data from a structure tested at the Los Alamos National Laboratory was employed. Identified structural changes with both simulation and experimental data properly indicated the location and extent of actual structural damage, which validated the proposed approach. [Copyright &y& Elsevier]

Novel green-red color-tunable Ca8(Mg,Mn)Tb(PO4)7:Eu2+ phosphors have been synthesized via the traditional solid-state method. Since Tb3+/Mn2+ ions are the parent ions in the lattice, the structural confinement occurs when the sensitizer Eu2+ is introduced into the Ca8(Mg,Mn)Tb(PO4)7:Eu2+ structure. The distance from Eu2+ to Tb3+/Mn2+ is confined in the 5 Å range, which induces a highly efficient energy transfer process. At Eu2+ 350 nm excitation, Ca8MgTb(PO4)7:Eu2+ shows dominant Tb3+ green emission with almost-vanished Eu2+ emission. Red emission is clearly observed as Mn2+ ions doping into Ca8MgTb(PO4)7:Eu2+, and color-tuning from green to red is realized by varying the Mn2+ contents. Eu2+–Tb3+–Mn2+ cascade energy transfer process is in effect due to short Eu2+–Tb3+/Mn2+ and Tb3+–Mn2+ distances, which is verified by PL and decay variations. Meanwhile, the Ca8(Mg,Mn)Tb(PO4)7:Eu2+ phosphor indicates good thermal stability and maintained the 45% emission level at 150 °C, which demonstrates their potential applications in white light LEDs. [ABSTRACT FROM AUTHOR]

Highlights: [•] Improved microstructure and electrical properties of HfTiO film by RTA at 500°C. [•] The largest k value of 44.0 and the lowest leakage current of 1.81×10−7 A/cm2. [•] Fabricate a MOSFET showing a good transistor performance. [ABSTRACT FROM AUTHOR]

Reactionof 4,4′,4″-{[(2,4,6-trimethylbenzene-1,3,5-triyl)tris(methylene)]tris(oxy)}tribenzoicacid (H3TCM) with Mn2+, Cu2+, andCo2+salts afforded four interesting metal–organicframeworks (MOFs), [Mn2(TCM)Cl(H2O)3]·3DMF·3CH3OH (1), [Mn4(TCM)2(CH3COO)2(DMF)5]·4CH3OH (2), [Cu2(TCM)(CH3COO)(DMF)(H2O)]·2DMF·3CH3OH(3) and [Co3(TCM)2(H2O)5]·5DMF·3CH3OH (4).Single crystal X-ray diffraction analysis revealed that the four structuresbased on the flexible TCM tripod consist of honeycomb lattices withdifferent metal–ligand macrocycles. The assembly of the metal–ligandmacrocycles and framework topologies is dependent on the coordinationgeometries of transition metal cations. The two-dimensional coordinationnetwork of 1was further connected by an auxiliary acetateligand to give rise to a three-dimensional honeycomb network of 2. The TCM ligand centered photoluminescences of these compoundsare very sensitive to the coordination modes of the TCM ligands, themetal secondary building units (SBUs), and their microstructures.These MOFs also present interesting magnetic behaviors, as revealedby the study of the magnetic susceptibilities. [ABSTRACT FROM AUTHOR]

Abstract: A new green-emitting SrB2O4:Tb3+ phosphor was synthesized by solid-state reaction. X-ray powder diffraction (XRD) analysis confirmed all the samples with orthorhombic formation of SrB2O4. The excitation spectra indicate the phosphor can be effectively excited by near ultraviolet (NUV) light, making it attractive as conversion phosphor for LED applications. The phosphor exhibits a bright green emission with the highest photoluminescence (PL) intensity at 544nm excited by 378nm light. The critical quenching concentration of Tb3+ in SrB2O4:Tb3+ is about 10mol%. The effects of charge compensators (Li+, Na+, and K+) on photoluminescence of SrB2O4:Tb3+ were also studied. The results show that the emission intensity can be improved by all the three charge compensators and Na+ is the optimal one for SrB2O4:Tb3+. All properties show that the phosphor is a promising green phosphor pumped by NUV InGaN chip for fabricating white light-emitting diodes (WLEDs). [Copyright &y& Elsevier]

In this study, methanol, ethanol, n‐propyl alcohol, isopropyl alcohol, acetone, and tert‐butanol were used as organic modifiers in reversed‐phase mode chiral liquid‐chromatography to systematically investigate the effects of mobile phase components on the enantioselective retention behavior of methyl mandelate with immobilized amylose 3,5‐dimethylphenylcarbamate‐based sorbent called Chiralpak IA. A two‐site enantioselective model was used to obtain information on the recognition mechanisms by observing the dependence of the enantioselectivity and retention factor difference on the modifier content. Similar enantioselective retention behaviors were observed for all modifiers, and characteristic modifier concentration points (PL, PM, and PH) were identified. At modifier concentrations up to PM, the weakened hydrophobic environment resulted in polymer structural relaxation, which changed the recognition mechanisms. By contrast, at concentrations beyond PH, considerably different enantioselectivity behaviors were observed, indicating that the existence of dipole‐dipole interaction, which was stronger at higher modifier concentrations, contributed to the retention mechanisms. The concentrations at which these characteristic points occurred were dependent on the carbon number of the modifier molecule. Modifiers with more carbon numbers facilitated the transition in the enantioselective behaviors. These results demonstrated that the proposed method can provide a physically consistent quantitative description of enantioselective retention behavior in reversed‐phase mode. [ABSTRACT FROM AUTHOR]

Abstract: A proteome-wide network approach was performed to characterize significant patterns of influenza A virus (IAV)–human interactions, and to further identify potentially valuable targets for prophylactic and therapeutic interventions. Topological analysis demonstrated a strong tendency for IAV to interplay with highly connected and central proteins located in sparsely connected sub-networks. Additionally, functional analysis based on biological process revealed a number of functional groups overrepresented for IAV interactions, in which regulation of cell death and apoptosis, and phosphorus metabolic process is the most highly enriched. In order to investigate whether these topological and biological features are significant enough to distinguish IAV targets from human proteome, a discrimination model was constructed based on these features using support vector machine coupled with genetic algorithm. The average result of overall prediction accuracy is 71.04% by leave-one-out across validation test. The optimized classifier was then applied to 9706 human proteins. As a result, 1418 novel genes were identified from human interactome, some of which were experimentally validated by others’ works to be important for IAV infection. The findings presented in this study might be important in discovering new drug targets for therapeutic treatments as well as revealing topological features and functional properties specific for viral infection. [Copyright &y& Elsevier]

Abstract: In the post-genomic era, one of the most important and challenging tasks is to identify protein complexes and further elucidate its molecular mechanisms in specific biological processes. Previous computational approaches usually identify protein complexes from protein interaction network based on dense sub-graphs and incomplete priori information. Additionally, the computational approaches have little concern about the biological properties of proteins and there is no a common evaluation metric to evaluate the performance. So, it is necessary to construct novel method for identifying protein complexes and elucidating the function of protein complexes. In this study, a novel approach is proposed to identify protein complexes using random forest and topological structure. Each protein complex is represented by a graph of interactions, where descriptor of the protein primary structure is used to characterize biological properties of protein and vertex is weighted by the descriptor. The topological structure features are developed and used to characterize protein complexes. Random forest algorithm is utilized to build prediction model and identify protein complexes from local sub-graphs instead of dense sub-graphs. As a demonstration, the proposed approach is applied to protein interaction data in human, and the satisfied results are obtained with accuracy of 80.24%, sensitivity of 81.94%, specificity of 80.07%, and Matthew''s correlation coefficient of 0.4087 in 10-fold cross-validation test. Some new protein complexes are identified, and analysis based on Gene Ontology shows that the complexes are likely to be true complexes and play important roles in the pathogenesis of some diseases. PCI-RFTS, a corresponding executable program for protein complexes identification, can be acquired freely on request from the authors. [Copyright &y& Elsevier]

Objective: To compare the clinical efficacy, safety and pain associated with the use of the LightSheer Duet HS as compared to the original LightSheer ET diode Laser for axillae hair removal in Chinese women. Methods: Thirty-six Chinese women received three axillae laser hair removal treatments using the LightSheer Duet HS on one side and the LightSheer ET on the other side. Subjects were evaluated for hair removal efficiency. The immediate pain associated with the treatments was noted. Results: At 1 month following the final laser treatment, hair reduction on the LightSheer Duet HS side and on the LightSheer ET side was 81 ± 13% and 85 ± 9% respectively. There was no statistical difference. Immediate pain scores at the first session on the LightSheer Duet HS sites and LightSheer ET sites was 5.71 ± 1.74 and 6.86 ± 1.80 respectively, which was statistically significant ( p < 0.05). Following the second and third sessions, immediate pain scores of the LightSheer Duet HS sites were both less than those of the LightSheer ET sites, but the differences were not statistically significant. Conclusions: The LightSheer Duet HS laser is a safe and effective method of hair removal in Chinese women. Treatment with the LightSheer Duet HS causes less pain. [ABSTRACT FROM AUTHOR]

Protein methylation is involved in dozens of biological processes and plays an important role in adjusting protein physicochemical properties, conformation and function. However, with the rapid increase of protein sequence entering into databanks, the gap between the number of known sequence and the number of known methylation annotation is widening rapidly. Therefore, it is vitally significant to develop a computational method for quick and accurate identification of methylation sites. In this study, a novel predictor (Methy_SVMIACO) based on support vector machine (SVM) and improved ant colony optimization algorithm (IACO) is developed to identify methylation sites. The IACO is utilized to find the optimal feature subset and parameter of SVM, while SVM is employed to perform the identification of methylation sites. Comparison of the IACO with conventional ACO shows that the IACO converges quickly toward the global optimal solution and it is more useful tool for feature selection and SVM parameter optimization. The performance of Methy_SVMIACO is evaluated with a sensitivity of 85.71%, a specificity of 86.67%, an accuracy of 86.19% and a Matthew's correlation coefficient (MCC) of 0.7238 for lysine as well as a sensitivity of 89.08%, a specificity of 94.07%, an accuracy of 91.56% and a MCC of 0.8323 for arginine in 10-fold cross-validation test. It is shown through the analysis of the optimal feature subset that some upstream and downstream residues play important role in the methylation of arginine and lysine. Compared with other existing methods, the Methy_SVMIACO provides higher Acc, Sen and Spe, indicating that the current method may serve as a powerful complementary tool to other existing approaches in this area. The Methy_SVMIACO can be acquired freely on request from the authors. [ABSTRACT FROM AUTHOR]

Abstract: A new ion-imprinted thiocyanato-functionalized silica gel sorbents was synthesized by the combination of a surface imprinting technique with a hydrothermal-assisted sol–gel process with Cd(II) as the template, 3-thiocyanatopropyltriethoxysilane (TCPTS) as the functional monomer, and epichlorohydrin as the cross-linking agent (IIP-TCPTS/SiO2) for the selective removal of Cd(II) from aqueous solution. The Cd(II)-imprinted thiocyanato-functionalized silica sorbents was characterized by FTIR, SEM, nitrogen adsorption and the static adsorption–desorption experiment method. The results showed that the maximum static adsorption capacity of IIP-TCPTS/SiO2 sorbents prepared by hydrothermal heating method was 2.3 times as much as the conventional heating method. The IIP-TCPTS/SiO2 sorbents offered a fast kinetics for the adsorption and desorption of Cd(II). The static uptake capacity and selectivity coefficient of IIP-TCPTS/SiO2 sorbents were higher than those of the non-imprinted sorbents. IIP-TCPTS/SiO2 sorbents had a substantial binding capacity in the range of pH 4.2–8.6 and could be used repeatedly. The Langmuir adsorption model was more favorable than the Freundlich adsorption model. Kinetic studies indicated that the adsorption followed a pseudo-second-order model. Various thermodynamic parameters such as ΔG°, ΔH° and ΔS° were evaluated with results indicating that this system was a spontaneous and endothermic process. The results showed that IIP-TCPTS/SiO2 sorbents could be employed as an effective material for the selective removal of Cd(II) from aqueous solutions. [Copyright &y& Elsevier]

Abstract: Background: The association of vitamin D receptor (VDR) gene polymorphisms to the lumbar degenerative disc disease has been previously studied; however, the role of VDR gene polymorphisms in cervical spondylosis remains unknown. Methods: One hundred fifty four patients with cervical spondylotic myelopathy (CSM) and 156 controls were enrolled. The clinical characteristics were collected and the severity of cervical spondylotic myelopathy was evaluated by magnetic resonance imaging (MRI). The VDR polymorphism genotyping was performed. Results: No significant difference in clinical characteristics was noted between the case and controls. For ApaI polymorphism, the cases had a marked higher prevalence of AA genotype (19.5% vs. 8.3%, P =0.003) and A allele frequencies (34.4% vs. 22.4%, P <0.001) than controls. For TaqI polymorphism, the cases had a significant higher prevalence of TT genotype (67.5vs. 44.2%, P <0.001) and T allele frequencies (76.9% vs. 54.2%, P <0.001) than controls. The odds ratio for CSM was 2.88 for the ApaI A allele carriers and 4.67 for the TaqI T allele carriers. The TaqI genotypes, both TT and TC showed a markedly higher MRI severity grading level than CC genotype (both P <0.01, compared with CC genotype). Conclusion: Certain VDR polymorphism is related in the presence and severity of CSM in Chinese subjects. [Copyright &y& Elsevier]