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In this study, silane agents were employed as organic silicon to synthesize organic-modified nickel phyllosilicates (NiPS), which were then introduced into epoxy resin (EP) to yield composites. The effects of these organic-modified NiPS on the curing behavior and flammability of epoxy composites were then investigated carefully. Though the added NiPS resulted in the initial temperature shifts to high temperature, the whole curing temperature ranges for EP composites became narrow regarding pure EP. Simultaneously, the activation energy of curing was also decreased, implying the lowered energetic barrier during the whole curing process. For all investigated samples, the overall reaction orders varied negligibly, and the predicted curves fitted well with the DSC thermograms. Finally, the positive influence derived from the presence of these organic-modified NiPS on the enhancement of self-extinguishing ability and limited oxygen index were also discussed, and the solid phase flame retardant mechanism was proposed.

Background Dual-energy computed tomography (DECT) can provide objective evaluation of laryngeal and hypopharyngeal squamous cell carcinoma (LHSCC). Purpose To investigate the relationship between quantitative parameters acquired from DECT and histopathological prognostic factors in LHSCC. Material and Methods A total of 65 patients with LHSCC who underwent arterial phase and venous phase DECT scans were retrospectively enrolled. Iodine concentration (IC) and normalized IC (NIC) of the tumor were calculated in both the arterial (ICA and NICA) and venous (ICV and NICV) phases, and compared among different pathological grades, T stages, and lymph node stages. Receiver operating characteristic (ROC) curves were generated to evaluate their diagnostic performance. Results There were significantly differences on ICA and NICA among three pathological grades (ICA, P = 0.001; NICA, P = 0.002). For differentiating moderately and poorly differentiated from well-differentiated LHSCC using ICA and NICA, the areas under curve (AUCs) were 0.753 and 0.726, respectively. High T stage (T3/4) LHSCC showed significantly higher ICA ( P = 0.012) and NICA ( P = 0.005) than low T stage (T1/2) LHSCC. The AUCs of the ICA and NICA were 0.674 and 0.703, respectively, in discriminating high from low T stage LHSCC. Lymph node metastasis (LNM)-positive (N1/2/3) LHSCC showed significantly higher ICA ( P = 0.008) and NICA ( P = 0.003) than LNM-negative (N0) LHSCC. For discriminating the LNM-positive from the LNM-negative group using ICA and NICA, the AUCs were 0.697 and 0.744, respectively. Conclusion ICA and NICA might be helpful in assessing histopathological prognostic factors in patients with LHSCC.

Structure parameters of work piece on muffler unit with simple expansion are determined using orthogonal experiment design method, and relationship model of total sound power of flow regenerated noise and flow velocity structure parameters is built, and the model parameters are solved, and quantity study of effect factors for the noise is performed. Results show that inlet diameter and expansion cavity length have high effect on flow regeneration noise, the reducing of the inlet diameter and improving expansion cavity length is in favor of the reduction of flow regeneration noise from muffler unit with simple expansion, and expansion ratio has less influence on the noise, the reducing of the expansion ratio makes the regenerated noise become less down.

Flaky ZnO thin films were electrodeposited from an aqueous solution of zinc nitrate (Zn (NO3)2) as electrolyte on ITO glass substrate by cathodic reduction method The effect of electrolyte concentration on the structure, morphology and optical properties of ZnO thin films were studied by X-ray diffraction, scanning electron microscopy and UV-Vis spectrometer. The results show that the ZnO films are of hexagonal wurtzite structure; When the concentration of Zn (NO3)2 solution is 0.24 M, the sparse flaky ZnO thin films were prepared and the thickness and length of ZnO flaky are about 50 nm and 1~3 μm, respectively; When the electrolyte concentration is 0.16 M, hexagonal and triangular structures are observed and some lathy and conical ZnO structure start to appear; When the concentration of Zn (NO3)2 solution drops to 0.08 M, the matrix of films is still flaky ZnO, but porous structures among the flaky structures appear and the size of conical ZnO has changed, whose bottom diameter reaches 1~3 μm and length is 2~4 μm; UV-Vis absorption test results indicate the absorption peak and the bandgap of the prepared ZnO thin films are about 350 nm and 3.28 eV, respectively.

AZ91D magnesium alloy and Al metal were bonded successfully at 450 oC with load of 25 or 31 MPa by using Mg-Al eutectic alloy as the solder in atmosphere. The microstructure of the AZ91D/Al joints was characterized by SEM equipped with EDS, and the bond strength was measured through three-point bending test. It was revealed that reactive diffusion occurred obviously at the jointing part. The diffusion layers are composed of α-Mg + β-Mg17Al12, β-Mg17Al12, γ-Mg2Al3 and α-Al. The average bend strength of AZ91D/Al joints is 24 MPa with maximum value 28 MPa. To demonstrate the potential engineering application of this technology, AZ91D magnesium alloy plate was coated with Al foil and its corrosion resistance was tested. Electrochemical test results showed that the corrosion resistance of Al coated AZ91D magnesium alloy plate was greatly improved compared with the uncoated one.

Hypopharyngeal squamous cell carcinoma (HSCC) has the worst prognosis among head and neck cancers. Cisplatin (DDP)-based chemotherapy is an important part of multimodal treatments. However, resistance to DDP severely impairs the effectiveness of chemotherapy for HSCC. Chloroquine (CQ) has been reported to enhance the effectiveness of chemotherapy and radiotherapy in liver, pancreas, breast, prostate and colon tumors, but it is unclear whether CQ could increase the efficacy of DDP for treating HSCC. We inoculated BALB/c nude mice with a subcutaneous injection of human hypopharyngeal FaDu cells to generate our animal model. Mice were randomly divided into 4 groups and treated with vehicle control, CQ (60 mg/kg/day), DDP (5 mg/kg/6 days), or a combination of DDP and CQ. Tumor growth and survival of the mice were monitored. We found that CQ inhibited autophagy and increased DDP-induced apoptosis in the xenograft mouse model. CQ enhanced the efficacy of DDP, resulting in decreased tumor growth and prolonged survival of the mice. To test whether blocking autophagy enhanced the efficacy of DDP, FaDu cells were infected with lentiviral shRNA to Beclin-1 and inoculated into the flanks of nude mice. Inhibition of autophagy markedly enhanced the DDP-induced antitumor effect. Our study suggests that the addition of CQ to DDP-based chemotherapy could be a potential therapeutic strategy for treating HSCC, and the inhibition of autophagy may contribute to chemotherapy sensitization in HSCC.