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ABSTRACT Highly efficient electrical conductive networks were constructed in carbon-black (CB)-filled polyoxymethylene (POM)-thermoplastic polyurethane (TPU)-polyamide 6 (PA6) ternary blends through the formation of a hierarchical structure composed of a minor PA6 phase as droplets inside one major phase (TPU) and CB particles localized at the TPU-PA6 interface by thermodynamically induced self-assembly. The hierarchical structure was thermodynamically predicted on the basis of the minimization of total interfacial energies and confirmed by electron microscopy. The degrees of the TPU phase continuity before and after the addition of PA6 were determined by solvent-extraction experiments. The percolation threshold of CB decreased by 50% compared to that in the POM-TPU binary blend because of the more efficient formation of a CB conductive network through CB-covered PA6 domains inside the TPU phase. The hierarchical structure not only increased the electrical conductivity of the composites but also improved their thermal stability in comparison with the simple structure formed by the homogeneously dispersed CB particles in POM. The method reported in this article can offer possibilities for improving the comprehensive properties of the conductive composites and the widening of their applications. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018, 135, 45877. [ABSTRACT FROM AUTHOR]

The effects of epoxy-functionalized glass fiber (GF) on the electrical conductivity, crystallization behavior, thermal stability, and dynamic mechanical properties of polyoxymethylene (POM)/thermoplastic polyurethane (TPU)/multiwalled carbon nanotube (MWCNT) composites are investigated. The electrical resistivities of POM/5%−20% TPU/1% MWCNT composites are significantly reduced by nine orders of magnitude after the addition of 20% GF because of the formation of TPU-coated GF structure facilitating the construction of conductive networks. GF has no obvious influence on the crystallization temperature, melting temperature, and degree of crystallinity of POM in POM/TPU/MWCNT composites because of their relatively bigger size compared with POM chains and MWCNTs. The storage moduli of POM/TPU/MWCNT composites are improved by the addition of GF, indicating that POM/TPU/MWCNT/GF composites are promising materials with good electrical and mechanical properties. POLYM. COMPOS., 38:1319-1326, 2017. © 2015 Society of Plastics Engineers [ABSTRACT FROM AUTHOR]

The effects of three types of electrically-inert fillers, calcium carbonate (CaCO), talc and glass fiber (GF), on electrical resistivity, crystallization behavior and dynamic mechanical properties of poly( m-xylene adipamide) (MXD6)/multiwalled carbon nanotube (MWCNT) composites are investigated. The electrical resistivity of MXD6/MWCNT composites is significantly reduced with the addition of inert fillers due to the volume-exclusion effect that leads to increased effective concentration of MWCNTs in MXD6 matrix and also due to improved MWCNT dispersion. The crystallization temperature of MXD6 increases with the addition of MWCNTs, indicating that MWCNTs can act as nucleating agent and induce crystallization of MXD6. The incorporation of inert fillers has no further effect on crystallization behavior of MXD6, but significantly improves the storage modulus of MXD6/MWCNT composite, demonstrating that CaCO, talc and GF filled MXD6/MWCNT composites are very promising materials with not only improved electrical property but also excellent mechanical properties. [ABSTRACT FROM AUTHOR]

The long-term lack of systematic morphological characteristic descriptions and species distinctions of ihoihecium Bruch & Schimp in China resulted in the difficult taxonomy. For further understanding of the classification of this genus, in addition to the study of original literatures of the related Orthothecium species, morphological characters of types and general specimens were observed. The specimens examined were collected from the United States, Canada, Russia, Sweden, Switzerland, Norway, Nepal and China (Inner Mongolia, Sichuan and Xinjiang). This study confirmed this genus species distribution in China. O. intricatum (Hartm.) Schimp was newly recorded in Inner Mongolia and Xinjing, O. rufescers (Dicks. Ex Brid.) Schimp newly recorded in Sichuan. Detailed morphological descriptions, illustrations and a key of three Orthothecium species were provided, promoting for the taxonomy study of Orthothecium and Plagiotheciaceae. [ABSTRACT FROM AUTHOR]

ABSTRACT The effect of glass fiber (GF) on the electrical resistivities of polyoxymethylene (POM)/maleic anhydride-grafted polyethylene (MAPE)/multiwalled carbon nanotube (MWCNT) composites is investigated. The POM/MAPE/MWCNT composites at a MWCNT loading of 0.75% are nonconductive because most of MWCNTs are isolated in the MAPE islands, and their electrical resistivities decrease significantly after the addition of GF because of the formation of MAPE-coated GF structure, which facilitates the formation of conductive paths and was confirmed by field emission scanning electron microscopy (FESEM). The formation of MAPE-coated GF structure is attributed to the interaction between GF and MAPE during melt compounding, as contrasted by the uncoated GF using high-density polyethylene (HDPE) instead of MAPE. Nonconductive POM/5-20% MAPE/0.75% MWCNT composites become conductive upon the addition of 20% GF. This preparation method for conductive materials can be generalized to POM/5-20% maleic anhydride-grafted polypropylene (MAPP)/0.75% MWCNT composites. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 41794. [ABSTRACT FROM AUTHOR]

In order to study methane generation yields from different types of crude oil within reservoirs and from residual bitumen within source rocks during thermal cracking process and to determine natural gas genetic types，pyrolysis experimental results in closed gold tube system have been systematically evaluated in the present study. Correlation between methane yields and heating temperatures has been established. Physical properties of crude oil exert critical influence on gas generation temperature and potential. Initial temperatures of gas generation from heavy oil and bitumen are lower than these from light oil and normal oil. In the early stage of oil cracking，methane yield from heavy oil is higher than that from normal oil and light oil. In the main oil cracking stage，methane yield from light oil exceeds normal oil and heavy oil rapidly and becomes the major contributor to gas inventory. Such difference is caused by their chemical compositions.Heavy oil is rich in resins and asphaltenes which have low activation energies so that its cracking to gas is easy，while its low methane yield is controlled by low H/C ratio. Light oil is rich in saturated hydrocarbons which have high activation energies so that its cracking to gas is difficult and starts at Easy% RO=1.5%，whereas its high methane yield is governed by high H/C ratio. The cracking of kerogen and residual bitumen within source rocks share some similarity as crude oils. Methane yield is controlled by H/C ratios with an order of Ⅰ>Ⅱ>Ⅲ in all situations. The chemical compositions of residual bitumen are similar to heavy oil，which is prone to crack at relatively low temperature due to lower activation energy. Meanwhile，clay minerals in source rocks can take a rule as catalyst，which can further facilitate thermal cracking process.Simulation results suggest that thermal cracking of residual bitumen starts at Easy% RO=1.0%. Such difference has significant impact on gas genetic type determination and resource potential evaluation in over matured petroleum systems like Sichuan Basin. [ABSTRACT FROM AUTHOR]

Background: Uveal Melanoma (UM) is the most prevalent primary intraocular malignancy in adults. This study assessed the importance of chromatin regulators (CRs) in UM and developed a model to predict UM prognosis. Methods: Gene expression data and clinical information for UM were obtained from public databases. Samples were typed according to the gene expression of CRs associated with UM prognosis. The prognostic key genes were further screened by the protein interaction network, and the risk model was to predict UM prognosis using the least absolute shrinkage and selection operator (LASSO) regression analysis and performed a test of the risk mode. In addition, we performed gene set variation analysis, tumor microenvironment, and tumor immune analysis between subtypes and risk groups to explore the mechanisms influencing the development of UM. Results: We constructed a signature model consisting of three CRs (RUVBL1, SIRT3, and SMARCD3), which was shown to be accurate, and valid for predicting prognostic outcomes in UM. Higher immune cell infiltration in poor prognostic subtypes and risk groups. The Tumor immune analysis and Tumor Immune Dysfunction and Exclusion (TIDE) score provided a basis for clinical immunotherapy in UM. Conclusion: The risk model has prognostic value for UM survival and provides new insights into the treatment of UM., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2023 Li, Xiong, Wu, Zhang, Wu, Chen, Xu and Liao.)

With 12 representative states such as Ohio and Illinois as examples, the disciplinary system for acupuncturists in the United States is introduced. The disciplinary system mainly covers several aspects such as the subject of the implementation, the types of illegal acts, the form of disciplinary responsibility, and the hearing procedure. The acupuncture industry association has the responsibility of disciplinary action in most states. Corresponding disciplinary measures will be taken depending on the illegal activities of acupuncturists according to the types of illegal practice specified by each state. The hearing procedure provides procedural guarantee for the subsequent rights protection activities of acupuncturists.