Poly(ethylene terephthalate) (PET) resin is one of the most widely used engineering plastic with high performance, but the poor impact strength limits its applications for the notch sensitivity. In this research, toughened PET alloy was prepared by blending recycled PET with polycarbonate (PC) and MDI (methylenediphenyl diisocyanate). Intrinsic viscosity and melt viscosity measurements proved increase of the molecular weights of PET via chainextending reaction. FTIR and DMA results proved that some PET-PC copolymers were produced and the compatibility of PET phase and PC phase was improved. In addition, the reaction induced by MDI also affected the crystallization behaviors of PET, as observed from DSC results, and the crytallinity of PET decreased with the increase of MDI content. For all of these effects of MDI of increasing of molecular weight, improving of compatibility, and limiting the crystallization behaviors of PET/PC alloy, the notched-impact strength was greatly improved from 17.3 to 70.5 kJ/m 2 .

This study aimed to propose a novel deep-learning method for automatic sleep apneic event detection and thus to estimate the apnea hypopnea index (AHI) and identify obstructive sleep apnea (OSA) in an event-by-event manner solely based on sleep sounds obtained by a noncontact audio recorder. Methods: We conducted a cross-sectional study of participants with habitual snoring or heavy breathing sounds during sleep to train and test a deep convolutional neural network named OSAnet for the detection of OSA based on sleep sounds. Polysomnography (PSG) was conducted, and sleep sounds were recorded simultaneously in a regular room without noise attenuation. The study was conducted in two phases. In phase one, eligible participants were enrolled and randomly allocated into training and validation groups for deep learning algorithm development. In phase two, eligible patients were enrolled in a test group for algorithm assessment. Sensitivity, specificity, accuracy, unweighted Cohen kappa coefficient (κ) and the area under the curve (AUC) were calculated using PSG as the reference standard. Results: A total of 135 participants were randomly divided into a training group (n, 116) and a validation group (n, 19). An independent test group of 59 participants was subsequently enrolled. Our algorithm achieved a precision of 0.81 and sensitivity of 0.78 in the test group for overall sleep event detection. The algorithm exhibited robust diagnostic performance to identify severe cases with a sensitivity of 95.6% and specificity of 91.6%. Conclusion: Our results showed that a deep learning algorithm based on sleep sounds recorded by a noncontact voice recorder served as a feasible tool for apneic event detection and OSA identification. This technique may hold promise for OSA assessment in the community in a relatively comfortable and low-cost manner. Further studies to develop a tool based on a home-based setting are warranted.

The most possible oxidative decomposition reaction path of EC–BOB−cluster.

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The processing of poly(ethylene terephthalate) (PET) involves thermal and hydrolytic degradation of the polymer chain, which reduces not only the intrinsic viscosity and molecular weight, but also the mechanical properties of recycled materials. A novel PET/bisphenol A polycarbonate/styrene-ethylene-butylene-styrene alloy based on recycled PET scraps is prepared by low temperature solid-state extrusion. Hydrolysis and thermal degradation of PET can be greatly reduced by low temperature solid-state extrusion because the extrusion temperature is between the glass-transition temperature and cold-crystallization temperature of PET. Modification of recycled PET by low temperature solid-state extrusion is an interesting method; it not only provides an easy method to recycle PET scraps by blend processing, but it can also form novel structures such as orientation, crystallization, and networks in the alloy.

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A new carbon coating method for improving the performance of anode material of lithium ion battery is proposed in this paper. In this method, cetyl trimethyl ammonium bromide (CTAB) is used as dispersant and phenolic resin formed in situ on Li 4 Ti 5 O 12 -TiO 2 is used as carbon precursor; thus, uniform coated sample with low carbon content is achieved. Three samples with different carbon contents are prepared, and their carbon content, morphology, structure, and electrochemical performance are investigated by thermogravimetry, scanning electron microscopy, transmission electron microscopy, X-ray diffraction, electrochemical impedance spectroscopy, and charge-discharge test. It is found that the sample with a carbon content of as low as 2.5 wt.% exhibits superior electrochemical performance. It delivers an initial capacity of 162.4 mAh g −1 with capacity retention of 95 % after 200 cycles at 1 C rate. When cycled at a higher rate of 5 C, the sample delivers a capacity of 148 mAh g −1 with no apparent capacity decaying after 90 cycles. The superior performance of the developed anode can be attributed to the uniform carbon coating.

Experiments were conducted to investigate the influence of CaO and CaCO3 on the capture efficiency of heavy metals during the combustion of municipal solid waste (MSW) in CO2/O2 and N2/O2 atmospheres. Six heavy metal elements were studied in this paper, including Pb, Cd, Cu, Cr, Ni, and Zn. On the basis of the results, the operating temperature has a great effect on the transformation of Pb and Cd, while the amount of Cu, Cr, and Ni in the bottom ash are affected only slightly by changes in the temperature and atmosphere. The volatilization of Cd, Cu, Cr, and Zn marginally decreased with the addition of CaCO3 or in a CO2/O2 atmosphere (oxy-fuel combustion). The X-ray diffraction results show that CaO and CaCO3 have the same ability to capture heavy metals under CO2/O2 and N2/O2 atmospheres as a result of the reaction of CaO with CO2. Thermodynamic equilibrium calculations indicate that CaO or CaCO3 could barely hinder the volatilization of heavy metals by chemical reactions with the heavy metals but might hinder their volatilization by their physical adsorption. The initial forms of the heavy metals in the MSW may be another factor that affects the volatilization of the heavy metals. The importance of these forms is indicated by these six heavy metals having similar enrichment behaviors in both the CO2/O2 and N2/O2 atmospheres with CaO or CaCO3 additives; the calculations predict that these heavy metals have the same main species, except for a slight change in the content of these species.