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Based on the actual processing of Xuan paper surface sizing, we used bone glue solution with mass fractions of 0.5–2.5% to apply manual drag-dye surface sizing. Organic elemental analysis, scanning electron microscopy, surface pH determination, water contact angle measurement, dynamic vapour sorption, and thermogravimetric analysis were used to characterize the bone glue content, surface properties and thermal stability of the sized Xuan paper. Different bone glue concentrations were retained uniformly and effectively on Xuan paper. The surface morphology of Xuan paper changed significantly after sizing due to the bone glue coating on the fibres and the fibre network. With an increase in sizing concentration from 1.0 to 1.5%, the hydrophobicity of the sizing Xuan paper's surface increased considerably. The weak acidity of bone glue solution lowered Xuan paper's surface pH. Increasing bone glue concentration can boost Xuan paper's saturation moisture absorption. When bone glue concentration was over 1.0%, sized Xuan paper's moisture absorption rate increased, while sized Xuan paper with a concentration below 1.0% showed a slight inhibition of moisture absorption within a certain humidity range. The sized Xuan paper with a concentration of 1.0% had a more stable and slower hygroscopic reaction in the absorption–desorption cycle. As bone glue concentration increased, Xuan paper's initial moisture content decreased and then increased, with the lowest value for sized Xuan paper at 1.0% concentration. The sized Xuan paper with a concentration of 1.0% bone glue showed the best thermal stability. Surface sizing should have little effect on Xuan paper's calcium carbonate content, but bone glue complicated its thermal behaviour. [ABSTRACT FROM AUTHOR]

The objective of this work is to evaluate the kinetic parameters from TG experiments toward the scale-up application in the flame spread modeling of polymers. Several series of TG experiments are conducted with PE sample mass of 5, 20, 50, 100 and 200 mg in N2 and air atmospheres. The little dependence of PE pyrolysis on sample mass in N2 atmosphere indicates that the strong effect of sample mass on PE oxidation in air atmosphere is not due to the non-uniform heating of large mass sample in crucible but the different reaction. The activation energies of PE oxidation here are normally larger for the case with more sample mass, which illustrates that the flame spread of PE could be overestimated if the lower activation energies for small sample mass are used. Finally, the kinetic parameters of PE in previous works and the results here for different sample mass suggest the reasonability and reliability of the parameters by TG experiments with larger sample masses for flame spread modeling in reality. The series of data for thermal kinetics with a wide range of sample mass here are helpful for the scale-up application of the microscale thermal analysis. [ABSTRACT FROM AUTHOR]

Activated carbons are widely used in the iodine adsorbers in nuclear plants, but little information about their combustibility is available for fire engineers. Series of TGA experiments were conducted for activated carbons, charcoal and XPS foam. The results show that the activated carbons oxidize strongly in air atmosphere but little in N2 atmosphere. The calculated activation energies of the wood AC, anthracite AC and coconut shell AC are, respectively, 100.56, 96.34 and 91.00 kJ mol−1, which are larger than that of the XPS foam, 55.95 kJ mol−1. However, the calculated activation energies of impregnated coconut shell activated carbon is 48.60 kJ mol−1, which is smaller than that of XPS foam. A new parameter, A12, is introduced to describe the amount of evaporative mass fraction during the fast pyrolysis stage. Additionally, the (Tp, DTGp) map and quarter division method is introduced to compare fire hazard of different materials. Finally, a quantitative fire hazard evaluation model is developed based on four important parameters: E, DTGp, Tp and A12. The calculated Relative Fire Safety Factors by this model for wood AC, anthracite AC, coconut shell AC, impregnated coconut shell activated carbon, charcoal and XPS foam are 1.49, 1.91, 1.51, 1.37 and 1.0, respectively. [ABSTRACT FROM AUTHOR]

An "off–on–off" fluorescent probe NapEb for high selectivity and reversible response to H2O2 and GSH was synthesized. Inspired by the role of GSH in the human body, the –Se–N– bond in ebselen was successfully used as the recognition site. The probe NapEb is sensitive (LOD = 8.4 µM) and fast for H2O2 (within 200 s). It can be used not only for qualitative and quantitative detection of H2O2 in real samples, but also has been successfully used for the imaging detection of H2O2 in MCF-7 cells with good effect. Moreover, continuous fluorescence recognition of GSH has also achieved significant results, the process is reversible and can be repeated for 5 times. The experimental results show that satisfactory results can also be obtained by structural modification at the 3-position of naphthalimide. [ABSTRACT FROM AUTHOR]

Firstly, the new single and combined error models applied to estimate the cumulative geoid height error are efficiently produced by the dominating error sources consisting of the gravity gradient of the satellite-equipped gradiometer and the orbital position of the space-borne GPS/GLONASS receiver using the power spectral principle. At degree 250, the cumulative geoid height error is 1.769 × 10-1 m based on the new combined error model, which preferably accords with a recovery accuracy of 1.760 × 10-1 m from the GOCE-only Earth gravity field model GO_CONS_GCF_2_TIM_R2 released in Germany. Therefore, the new combined error model of the cumulative geoid height is correct and reliable in this study. Secondly, the requirements analysis for the future GOCE Follow-On satellite system is carried out in respect of the preferred design of the matching measurement accuracy of key payloads comprising the gravity gradient and orbital position and the optimal selection of the orbital altitude of the satellite. We recommend the gravity gradient with an accuracy of 10-13-10-15/s2, the orbital position with a precision of 1-0.1 cm and the orbital altitude of 200-250 km in the future GOCE Follow-On mission. [ABSTRACT FROM AUTHOR]

Using an ultra-sensitive differential scanning calorimetry (US-DSC), we have investigated the folding and aggregation behaviors of poly(N-isopropylacrylamide) (PNIPAM) chains in dilute and semidilute solutions. In the heating process, the intrachain folding and `interchain: aggregation simultaneously occur in the dilute solutions, and the ratio of intrachain folding increases with decreasing concentration. In the semidilute solutions, PNIPAM chains show limited interchain aggregation with elevated temperature, because most of the PNIPAM chains have been collapsed at: lower temperature. In an extremely dilute solution, PNIPAM chains undergo a single folding transition in the heating process. By extrapolating heating rate and concentration to zero, we have obtained the phase transition temperature (T[subs]) and enthalpy change (ΔH[subs]) of the single chain folding. ΔH[subs] is higher than that for a phase transition involving intrachain collapse and interchain aggregation, indicating that a single chain folding can not be taken to be a macroscopic phase transition. [ABSTRACT FROM AUTHOR]