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Mass sensors based on carbon nanotubes (CNTs) may provide excellent sensing resolution owing to the high aspect ratio of CNTs. However, they are prone to large displacement, resulting in nonlinear oscillation behavior. In particular, the geometric nonlinear characteristics and temperature load during preparation can directly affect the sensing performance of CNTs sensing devices. Herein, the von-Kármán geometric nonlinearity caused by large displacement and the size effect based on nonlocal strain gradient field were introduced, and the dynamic model of nonlinear nano-mass sensor was established. The nonlinear response equation of the system was derived based on Hamilton's principle to describe the detection sensitivity for deposited particles at any position of the sensor. The nonlinear frequency shift equation describing the detection sensitivity of the system was then obtained. To intuitively verify the nonlinear oscillation behavior of the sensor under the working state, a molecular dynamics simulation process was designed according to the influencing key physical parameters on the nonlinear behavior and detection sensitivity of the system. The detection sensitivity design formula and simulation verification process revealed high-performance and efficient designed sensors. [ABSTRACT FROM AUTHOR]

A new self-assembled cellulose (SACS) containing multi-functional amine, carboxyl and hydroxyl groups was successfully obtained through etherification, cross-linking and grafting processes. Then, the adsorption of sulfamethoxazole (SMZ) and Cd(II) onto SACS at pH values of 3, 5.7 and 7.5 was systematically investigated by batch experiments of single, sequential and binary systems, characterization and density functional theory (DFT) calculations. The presence of Cd(II) decreased the adsorption of SMZ because of hydrophilic site competition, while SMZ inversely increased the adsorption of Cd(II), which was attributed to bridging and especially to electrostatic shielding effects; moreover, both the inhibitory and synergistic effects were more obvious in the binary system and at a pH of 7.5. There was a dynamic balance between the inhibitory and synergistic effects that depended on the system, pH value and concentration ratio. DFT results further indicated that SMZ– more easily coordinated with Cd(II) at sulfonyl oxygen and nitrogen sites, and the cationic bridge of Cd(II) with SMZ– mainly occurred in the sequential system. Moreover, a complexation–decomplexation–complexation balance of SMZ– and Cd(II) probably occurred in the binary system. ga1 • Cellulose was assembled with amine, carboxyl and hydroxyl groups. • The cationic bridge of Cd(II) for SMZ– mainly occurred in the sequential system. • Both competition and the inhibitory effect were most obvious at a pH of 7.5. • SMZ– more easily coordinated with Cd(II) at sulfonyl oxygen and nitrogen sites. • A complexation–decomplexation–complexation balance occurred in the binary system. [ABSTRACT FROM AUTHOR]

YAG:Ce3+ phosphor-in-glass slices were fabricated and their potential applications in light emitting diodes were investigated in the present work. The optical properties of the fabricated glass slices show obvious dependence on the thicknesses and the contents YAG:Ce3+ phosphor powder in glass slices. The fabricated glass slices have excellently thermal stability, which is demonstrated by the heating experiments in the temperature range of 25–250 °C and the accelerated thermal aging experiments with 20 days. The electroluminescence of light emitting diodes was tuned by changing the thickness of glass slices and the contents of YAG:Ce3+ phosphor powders in the glass slices. The results in the present work show that YAG:Ce3+ phosphor-in-glass slices are prospective to replace the conventional epikote/silicon-based phosphor converter for the construction of light emitting diodes. [ABSTRACT FROM AUTHOR]

We synthesized a series of YPO 4 :Ce 3+ /Tb 3+ /Eu 3+ phosphors by a solid state reaction. All of phosphors have a single phase, showing that the doping ions could not change the phase of YPO 4 host. The emission intensities of Ce 3+ , Tb 3+ and Eu 3+ ions clearly depend on the Tb 3+ concentrations in YPO 4 :Ce 3+ /Tb 3+ /Eu 3+ phosphors. The emission intensity of Ce 3+ emission decreases gradually but the emission intensity of Eu 3+ emission increases continuously with the increasing Tb 3+ concentration because of the energy transfer from Ce 3+ to Eu 3+ through Tb 3+ . On the basis of the luminescent properties of YPO 4 :Ce 3+ /Tb 3+ /Eu 3+ phosphors, the possible energy transfer mechanism was speculated. [ABSTRACT FROM AUTHOR]

A cellulose-polyacrylic acid-TiO 2 composite (CAT) with multiple carboxyl groups in the network structure and that could undergo ultrafast adsorption was successfully synthesized, and the adsorption capacity for cadmium(II) (Cd(II)) under optimal conditions was as high as 105 mg/g within 5 min. Additionally, CAT maintained the advantages of fast and efficient adsorption even when the concentrations of potentially interfering ions (NaCl, MgSO 4 , HA) were high. Importantly, 13 nonlinear kinetic models, including 6 empirical models and 7 diffusional models with their 5 error functions, were used to evaluate the adsorbent performance and mass transfer mechanism. As a result, regardless of whether interfering ions were present, the PNO model and Langmuir kinetics model were perceived as the best fit for the adsorption reaction and empirical model and mass transfer model, respectively. Adsorption at active centers was the rate limiting step for CAT. Moreover, the micromechanisms were also quantitatively explained with multiple DFT calculations, which illustrated ion exchange and electrostatic interactions with the oxygen atom on the introduced carboxyl group. [Display omitted] • Synthesis of ultrafast cellulose-TiO 2 composite adsorbent with multiple carboxyl. • CAT maintained fast and efficient adsorption of Cd (II) whether interfering ions. • 13 nonlinear kinetic models quantitatively evaluated adsorbent performance. • 5 error functions were summarized to determine the best fitting model. • DFT calculations further verified the main micromechanisms of ion exchange. [ABSTRACT FROM AUTHOR]

• PCCSF was synthesized successfully through the chelating modification. • PCCSF exhibited excellent adsorption capacities of SD, SMM and SMZ. • Adsorption behavior and mechanisms depended on various pH values. • Electrostatic repulsion and hydrophobic interactions decreased adsorption capacity. • Lewis acid-base interaction, EDA and CAHB were favor for adsorption. Phosphonic chelating fiber (PCCSF) as a novel adsorbent was produced through alkalization, etherification, amination and phosphonation, and then it was applied to adsorb sulfonamides (SAs), such as sulfadiazine (SD), sulfamonomethoxine (SMM) and sulfamethoxazole (SMZ). Specially, their adsorption behavior at different pH values was studied. As a result, PCCSF was provided with amino (NH 2 or NH) and PO(OH) 2 (P O) groups, and its equilibrium data were generally represented by both Langmuir and Freundlich models. Combining adsorbent-to-solution distribution coefficients (K d) values and the effect of pH, the primary mechanism suggested that adsorption capacity of PCCSF was lower in strong acid and alkali solution, due to the electrostatic repulsion and hydrophobic interactions. By contrast, its adsorption affinity became more excellent at 3 < pH < 9 owing to the π-π electron-donor-acceptor (EDA) charge-assisted H-bond, Lewis acid-base interaction and charge-assisted H-bond (CAHB). [ABSTRACT FROM AUTHOR]