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Mechanically-strong sodium alginate/clay aerogel were fabricated by addition of p-toluenesulfonic acid using a freeze-drying method. The adjusting of pH from 8 (the control) to 6, on the one hand lead to the crosslinking of alginate, on the other hand thickened the clay sol. The compressive modulus of A5C5 aerogel significantly increased from 6.0 ± 0.4 MPa (pH = 8) to 17 ± 3 MPa (pH = 6). The morphological structure characterization showed that the microstructure of aerogels changed from layered to network with decreasing pH value, with cell size ranging from 4 to 8 μm. The rheological behavior showed that the addition of p-toluenesulfonic acid would significantly improve the viscosity of the precursors at low frequency. The combustion tests indicated that all the alginate/clay aerogels possess excellent flame retardancy. The addition of p-toluenesulfonic acid further slightly increased the thermal stability and fire safety of the material. This facile preparation procedure of strengthened polymer/clay aerogel via adjusting pH is promising and can be spread.

To obtain a substitute for petroleum-based polyols and simultaneously solve the flammability problem of polyisocyanurate (PIR) foams, a novel phosphorus-containing soy-based polyol (PCSO) was firstly synthesized. Then, PCSO was used to fabricate biomass flame-retardant PIR foam (P-PIR) by fully replacing petroleum-based polyol. The morphology, compressive strength, thermal conductivity, thermal stability, flammability, and flame-retardant mechanism were studied for the developed PIR. The incorporation of PCSO results in a slight decrease in the compressive strength and an increase in the flame retardancy of PIR foam. To further improve the flame retardancy, a commercial phosphorus-containing polyol (BY30) and an expandable graphite (EG) were added in the P-PIR system. The test results show that the decompositon of PIR was hindered after 330 °C and the char residue was significantly improved. In addtion, the limiting oxygen index of PIR was significantly increased to 35%, and the peak of heat release rate and total heat release were dramatically decreased by 65% and 87%, respectively. A synergistic flame-retardant effect was achieved by combining the gas phase action of PCSO and BY30 with the condensed phase action of EG.

Ammonium polyphosphate (form I APP) was modified via ion exchange reaction with ethylenediamine, and the resulting modified ammonium polyphosphate (MAPP) was used alone to prepare intumescent flame-retardant (IFR) polypropylene (PP) via melt blending. The flame retardancy of PP containing MAPP was investigated by limiting oxygen index (LOI), vertical burning test (UL-94) and cone calorimeter (CC). The LOI value of PP containing 40 wt% of MAPP reached 32.5%, which increased by 56.9% compared with that of PP with the same content of APP, and the UL-94 rating was V-0 in the case of specimen thickness of 1.6 mm, while the latter had no rating. CC test results showed that the heat release rate (HRR), the mass loss rate (MLR) and the smoke production rate (SPR）of PP/MAPP system decreased significantly compared with neat PP and PP/APP systems. Especially the fire growth rate (FGR) and SPR peak of PP containing 35 wt% MAPP decreased by 89.1% and 63.2% respectively compared with those of PP containing 35 wt% APP. These results demonstrated that only by incorporating the MAPP without additional charring agents, could PP be successfully flame retarded. Fourier transform infrared spectroscopy (FTIR) etc. were used to investigate the flame retardant mechanism of MAPP, and it was found that both the generation of carbon–carbon double bonds after the scission of C–N bonds and the residue consisting of some stable structures such as P–N–C and C–N etc. caused the charring ability to increase dramatically, which must be the principal reason for the much better flame retardancy of PP/MAPP system without any additional charring agent compared with APP.

Aerogel composites based on melamine-formaldehyde (MF) and alginate (A) was fabricated with ice-templated method. The preparation process involves two cross-linking processes, in aerogel precursor at room temperature and in dried aerogel at 80 °C (100% humidity), respectively. Cross-linking was demonstrated to be very efficient for improving the mechanical property and water resistance of MF-A aerogels. The obtained aerogels have compressive moduli ranging from 1.2 MPa to 24.1 MPa. All the cross-linked aerogels display good dimensional stability when soaked in water. The morphological study of MF-A aerogels show a layered or network microstructure, with a homogeneous distribution of MF spheres. Due to low density and porous structure, MF-A aerogels have low thermal conductivity from 0.035 to 0.047 W/m K. MF-A aerogels have good thermal stability and extremely low flammability, with LOI value up to 41%. This novel aerogel from partially bio-based raw material would have promising application prospects.

To explore the synergism and mechnism of diverse forms of copper-decorated graphene on improving the fireproof efficiency of ammonium polyphosphate (APP) based polyamide-cured epoxy resin (EP), Cu(0) and Cu(II) decorated graphene hybrids (Cu2+-GO, Cu-rGO and CuO-GNS) were prepared through facile methods and used as synergists in EP/APP system. Cu2+-GO exhibits better synergistic effect with APP than Cu-rGO and CuO-GNS on reducing heat release of EP. Because Cu2+ is easier than Cu and CuO to go through various oxidation states and intermediates, which catalyze EP/APP system rapid formation of protective char layer containing crosslinked junctions of P (V) organic phosphates and Cu (II) salts. CuO-GNS exhibits better smoke suppression and harmful gases reduction in EP/APP matrix, such as aliphatic hydrocarbons, aromatic compounds and CO, due to its better conversion of CO to CO2 through a redox cycle. This work provides a promising strategy for preparation of EP with excellent flame retardancy and smoke suppression at low addition.

We develop a framework for assessing the quality of stereoscopic images that have been afflicted by possibly asymmetric distortions. An intermediate image is generated which when viewed stereoscopically is designed to have a perceived quality close to that of the cyclopean image. We hypothesize that performing stereoscopic QA on the intermediate image yields higher correlations with human subjective judgments. The experimental results confirm the hypothesis and show that the proposed framework significantly outperforms conventional 2D QA metrics when predicting the quality of stereoscopically viewed images that may have been asymmetrically distorted.

An efficient flame retardant polymeric synergist poly[ N 4 -bis(ethylenediamino)-phenyl phosphonic- N 2 , N 6 -bis(ethylenediamino)-1,3,5-triazine- N -phenyl phosphonate] (PTPA) was designed and synthesized from cyanuric chloride, ethylenediamine and phenylphosphonic dichloride. It was characterized by Fourier Transform Infrared (FTIR), 1 H NMR and 31 P NMR, Elemental Analysis (EA) and Inductively Coupled Plasma Atomic Emission Spectrometry (ICP-AES). Combined with ammonium polyphosphate (APP), a new intumescent flame retardant (IFR) was obtained. The flammability behaviors of polypropylene (PP)/IFR system were investigated by limiting oxygen index (LOI), vertical burning test (UL-94) and cone calorimetry. With 25 wt% of IFR (APP:PTPA = 2:1), the PP/IFR system could achieve a LOI value of 34.0% and UL-94 V-0 rating, and the heat release rate (HRR), peak heat release rate (PHRR), total heat release (THR) and smoke production rate (SPR) were considerably reduced, especially HRR and SPR were decreased by 85% and 79%, respectively. The results indicate that there is an excellent synergism between APP and PTPA, which endows PP with both good flame retardancy and good smoke suppression. Furthermore, the thermal degradation mechanism of IFR and the flame-retardant mechanism of PP/IFR system were investigated by thermogravimetric analysis (TGA), FT-IR, TG-FTIR and scanning electron microscope (SEM). The study on the flame-retardant mechanism of IFR indicated that a structure containing –CN was formed due to the reaction between APP and PTPA.

Meconium is a matrix that can be obtained easily and noninvasively and is useful for detecting antenatal fetal exposure to environmental toxins. Taiwan is an island with high fish consumption, and many pregnant women would like to enjoy the benefits of fish without jeopardizing their health or that of their child. The aim of this study is to assess the mercury concentration in meconium in relation to the health risk of mercury exposure. A total of 198 mother-infant pairs residing in the city of HsinChu were recruited for the study between January 2007 and June 2007. The average mean concentration of mercury in meconium was 79.2+/-7.3 ng g(-1) dry wt We use the Monte Carlo technique to assess the uncertainty in risk assessment and the impact of these uncertainties on the estimation of expected risk of mercury intake from fish in mothers. Based on the FAO/WHO's tolerable daily intake of methylmercury (0.23 microg kg(-1)d(-1)), we found that 17.3% and 14.0% of the daily mercury exposure estimated exceeded the reference dose for foreign-born and Taiwan-born mothers, respectively. We found that the mercury concentration in meconium was much higher than in other studies, except for one study done in Tagum in the Philippines where mercury is used in gold mining. This may be because Asia is the largest emitter of anthropogenic mercury, accounting for 53% of worldwide emissions. Sensitivity analysis suggests that mercury concentration in fish and the rate of ingesting fish may be the key parameters for governments offering risk management guidance to protect the health of mothers and unborn babies.