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Curing behaviors and copolymerization mechanisms between phthalonitrile-based resin containing benzoxazine (A-ph) and cyanate ester (CE) were characterized and discussed. Results indicated that copolymerization between A-ph and CE were comprised of ring-opening polymerization of oxazine rings and ring-forming polymerization of cyanate and nitrile groups. From them, ring-opening of oxazine occurred preferentially, followed by ring-forming of cyanate and nitrile groups, which were promoted by active hydrogen and amine structures generated from ring-opening of oxazine. Moreover, with increasing the content of CE (≥40 wt%), self-polymerization of cyanate would dominate the components of the resulting composites and reduces the thermal stability of fiber-reinforced composite laminates. Additionally, mechanical properties of composite laminates were also affected by the content of CE. Composite laminates with 10 wt% CE showed the highest flexural strength (622 MPa). The improved mechanical properties were also verified with investigation of dynamic thermomechanical analysis and morphology of fracture surfaces. These findings are helpful to improve the thermosetting resins in terms of their chemical structure, material properties, and processability.

Background: Healthcare-associated infections (HAIs) are still a major health threats worldwide.Traditional surveillance methods involving manual surveillance by infection control practitioners (ICPs) for data collection processes are laborious, inefficient, and generate data of variable quality. In this study, we sought to evaluate the impact of surveillance and interaction platform system (SIPS) for HAIs surveillance compared to manual survey in tertiary general hospitals.Methods: A large multi-center study including 21 tertiary general hospitals and 63 wards were performed to evaluate the impact of electronic SIPS for HAIs.Results: We collected 4,098 consecutive patients and found that the hospitals installed with SIPS significantly increased work efficiency of ICPs achieving satisfactory diagnostic performance of HAIs with Chen et al. SIPS and HAIs

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A pH-responsive aqueous two-phase system (pH-ATPS) has been developed by sodium citrate and a recyclable pH-responsive polymer P that can response to the change of pH values. Phase separation mechanism is studied through Low field-NMR. All variables affecting the phase separation are evaluated. Phase characteristics (viscosity, density, interfacial tension) and phase separation kinetic are studied for understanding of separation process and operational parameters in applications. This pH-ATPS has the characters of low interfacial tension, high recovery leading efficient mass transfer and low cost. The proposed system can be used as a mild medium for extractive bioconversion with low cost. We applied this pH-ATPS in extractive bioconversion of cefprozil. Cefprozil is partitioned towards the polymer-rich phase while the substrates tended to be partitioned in the salt-rich phase. Extractive bioconversion of cefprozil in this pH-ATPS can improve yield of the enzymatic process and reduce the product hydrolysis in optimal conditions. The maximal conversion yield of cefprozil in the studied system is 91.0%.

The solubilities of 3,4-dinitro-1H-pyrazole (DNP) in different solvents are essential for crystallization and further theoretical studies. In this paper, the solubilities of DNP in six pure solvents were determined in temperatures ranging from 298.15 K to 338.15 K by the dynamic laser monitoring method under atmospheric pressure. The results showed that the solubility of DNP in each tested solvent increases with the increasing temperature. Melting temperature T m and fusion enthalpy ΔH fus of DNP were determined using differential scanning calorimetry. Solubility data was correlated by the modified Apelblat equation, λh equation, Wilson model and nonrandom two-liquid (NRTL) model, and these results showed that all models can give satisfactory correlation results. Therefore, the experimental data and model parameters would provide essential support for industrial design. Furthermore, on the basis of the NRTL model and solubility data, the dissolution thermodynamic properties, including enthalpy, entropy, and Gibbs energy were determined.

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