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•The chlorine removal was mainly depended on the HTC temperature.•The inorganics removal was mainly depended on the adulteration of PVC.•The dechlorination efficiency reached about ...84% without any chemical additives.•The positive synergistic effect was observed for inorganics and chlorine removal.•Clean solid fuel was produced by co-hydrothermal carbonization of PVC and sawdust.
This work proposes an innovative integrated process to produce clean solid biofuel from chlorinated wastes and polyvinyl chloride (PVC). The PVC and pinewood sawdust were used as parent materials. We studied the effect of parameters such as the hydrothermal temperature, the residence time and the particle size (PS) of the sawdust on the dechlorination efficiency (DE), the inorganics removal efficiency (RE), and the HHV of hydrochar. The co-hydrothermal carbonization (Co-HTC) process was performed by mixing the PVC and pinewood sawdust at a mass ratio of 1:9. For the DE, the most important factor was the hydrothermal temperature, followed by residence time and particle size of pine sawdust. The DE could reach about 84% by the co-HTC at a temperature of 260 °C for 120 min. The particle size of pine sawdust has noticeable effect on DE because of heat and mass transfer. The DE was decreased from 79.17% to 71.12% when the PS was increased from 0.22–0.49 to 0.6–0.9 mm. The RE of inorganics from pine sawdust was significantly promoted because the addition of PVC enhanced the acidity of the reaction system, regardless of the co-HTC operating parameters investigated in this work. The temperature increase is conducive for the removal of K and Na. The maximal RE of Al, Ca, and Mg increased significantly from 49.39%, 49.19% and 41.86 to 97.61% (Da-260-30), 98.59% (Da-260-90) and 97.66% (Dc-260-30), respectively. The maximal RE of Fe, K and Na increased from 49.79%, 50.80% and 47.44% to 92.82% (Da-220-30), 92.32% (Dc-260-30) and 87.43% (Dc-260-30), respectively. The oxygen-containing functional groups decreased with the increase of HTC temperature (220–260 °C), residence time (30–90 min) and particle size (0.22–0.49 to 0.6–0.9 mm), resulting in the weakening absorption ability of hydrochar for inorganics. The addition of PVC and the temperature increase are not conducive to the formation of porous hydrochar. Nevertheless, the residence time extension and particle size growth could increase the porosity of hydrochar. The hydrochar with low chlorine, low inorganics content and improved higher heating value (HHV) of 24–30 MJ/kg was similar to bituminous coal, which could be utilized as clean solid biofuels. A high-energy yield of 74–81% was achieved by this co-HTC process. These results show that the co-HTC of PVC with biomass was feasible for clean biofuel production, because the chlorine and inorganics could be removed effectively by the positive synergistic effect. This work provides a new viewpoint for the development of WtE and biomass upgrading technologies.
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•We report a novel rectangle-like GOWR and fabricate the GOWR wrapped MF sponge.•The MF@GOWR shows good hydrophobicity, acidic/alkaline tolerance, reversible compressibility, ...excellent flame resistance.•An ultrafast alarm response to flame attack and abnormal high temperature was achieved.•The distinct resistance transition mechanism of MF@GOWR sponge was studied.•The MF@GOWR sensor offers a promising strategy for fire safety application outdoor.
Fire prevention and safety of combustible materials is a global challenge. To reduce their high fire risk, traditional smoke detectors are widely used indoor via detecting smoke product after combustion; however, they usually show a long response time and limitation for outdoor use. Herein, we report a temperature-induced electrical resistance transition of graphene oxide wide-ribbon (GOWR) wrapped sponges to reliably monitor fire safety of the combustible materials. Novel rectangle-like GOWR sheets are synthesized from unzipping carbon nanofibers and used to fabricate GOWR wrapped melamine formaldehyde sponges with multi-functionalities, e.g. lightweight, good hydrophobicity, reversible compressibility, excellent acidic/alkaline tolerance and flame resistance. The GOWR sheets on the sponge skeleton can be in-situ thermally reduced once encountering a flame attack or abnormal high temperature, inducing a distinct transition in electrical resistance. Consequently, an ultrafast alarm response of ∼2 s to flame attack is triggered, and rapid fire early warning signals to abnormal high temperatures, e.g. ∼33 s at 300 °C, are achieved below ignition temperature of most combustible materials. This method drives substantial motivation and opportunity to develop advanced fire detection and early warning sensors for reducing the high fire risk of various combustible materials in outdoor applications.
Relaxor-ferroelectrics are fascinating and useful materials, but the mechanism of relaxor-ferroelectricity has been puzzling the scientific community for more than 65 years. Here, a theory of ...relaxor-ferroelectricity is presented based on 3-dimensional-extended-random-site-Ising-model along with Glauber-dynamics of pseudospins. We propose a new mean-field of pseudospin-strings to solve this kinetic model. The theoretical results show that, with decreasing pseudospin concentration, there are evolutions from normal-ferroelectrics to relaxor-ferroelectrics to paraelectrics, especially indicating by the crossovers from, (a) the sharp to diffuse change at the phase-transition temperature to disappearance in the whole temperature range of order-parameter, and (b) the power-law to Vogel-Fulcher-law to Arrhenius-relation of the average relaxation time. Particularly, the calculated local-order-parameter of the relaxor-ferroelectrics gives the polar-nano-regions appearing far above the diffuse-phase-transition and shows the quasi-fractal characteristic near and below the transition temperature. We also provide a new mechanism of Burns-transformation which stems from not only the polar-nano-regions but also the correlation-function between pseudospins, and put forward a definition of the canonical relaxor-ferroelectrics. The theory accounts for the main facts of relaxor-ferroelectricity, and in addition gives a good quantitative agreement with the experimental results of the order-parameter, specific-heat, high-frequency permittivity, and Burns-transformation of lead magnesium niobate, the canonical relaxor-ferroelectric.
Abstract
Motivation
The Oxford Nanopore sequencing enables to directly detect methylation states of bases in DNA from reads without extra laboratory techniques. Novel computational methods are ...required to improve the accuracy and robustness of DNA methylation state prediction using Nanopore reads.
Results
In this study, we develop DeepSignal, a deep learning method to detect DNA methylation states from Nanopore sequencing reads. Testing on Nanopore reads of Homo sapiens (H. sapiens), Escherichia coli (E. coli) and pUC19 shows that DeepSignal can achieve higher performance at both read level and genome level on detecting 6 mA and 5mC methylation states comparing to previous hidden Markov model (HMM) based methods. DeepSignal achieves similar performance cross different DNA methylation bases, different DNA methylation motifs and both singleton and mixed DNA CpG. Moreover, DeepSignal requires much lower coverage than those required by HMM and statistics based methods. DeepSignal can achieve 90% above accuracy for detecting 5mC and 6 mA using only 2× coverage of reads. Furthermore, for DNA CpG methylation state prediction, DeepSignal achieves 90% correlation with bisulfite sequencing using just 20× coverage of reads, which is much better than HMM based methods. Especially, DeepSignal can predict methylation states of 5% more DNA CpGs that previously cannot be predicted by bisulfite sequencing. DeepSignal can be a robust and accurate method for detecting methylation states of DNA bases.
Availability and implementation
DeepSignal is publicly available at https://github.com/bioinfomaticsCSU/deepsignal.
Supplementary information
Supplementary data are available at bioinformatics online.
A flame-retardant graphene oxide (GO) based nanocomposite paper was prepared for efficient fire alarm response via a one-step and green 3-mercaptopropyltrimethoxysilane (MPTS) functionalization ...process. Such MPTS modification not only improves thermal stability and flame resistance of GO network, but produces ultra-fast flame detection and efficient fire early warning response. Typically, the MPTS-GO-10 wt% paper shows a flame detection response signal of about 1.0 s and improved fire early warning response time at a relatively temperature of 200 °C. The structural observation and analysis suggest that the thermal reduction behavior of GO network can be promoted by the sulfydryl groups of MPTS molecules at high temperature, thus producing the rapid and sensitive transition of electrical resistance form insulating GO into conductive reduced GO network. The MPTS functionalization developed here show promising to tailor fire early warning response of flame-retardant GO based fire alarm sensor for potential fire safety and prevention applications.
Flame-retardant silane-grafted-graphene oxide (silane-GO) papers are fabricated via a green and versatile silane-assisted assembling strategy, and their use as early fire alarm sensors are ...investigated. Different silane molecules with alkoxy groups can react with GO in aqueous solution via hydrolysis and condensation reactions and thus assemble into the aligned silane-GO papers. The silane-GO papers exhibit good mechanical flexibility, strong acidic/alkaline tolerance, excellent flame resistance and improved thermal stability at low silane content in comparison with pure GO paper. Structure observation and analysis disclose that a compact nano-silica protective layer transformed from the grafted silane molecules during combustion is formed to inhibit the thermal degradation of GO sheet effectively. Furthermore, the insulating silane-GO paper can be thermally reduced into the conductive reduced GO network after encountering high-temperature or flame situation, thus providing ideal early fire alarm response, i.e. rapid flame detecting response time of ∼1.6 s and fire early warning response of ∼5 s when attach on the heat resistor. These results suggest that the silane-GO papers are promising for development of advanced materials as smart sensors in early fire alarm applications.
A facile and green silane-assisted assembling technique was developed to fabricate flame-retardant graphene oxide papers, showing fast flame detection and ideal early warning response. Display omitted
•A facile silane-assisted assembling strategy was developed to fabricate flame-retardant graphene oxide (silane-GO) papers.•Different silane molecules with alkoxy groups were assembled well onto the aligned silane-GO papers.•The silane-GO papers exhibited good mechanical flexibility, strong acidic/alkaline tolerance, and excellent thermal stability and flame resistance.•The related flame-retardant mechanisms were analyzed and discussed.•The silane-GO papers showed fast fire alarm response due to temperature-triggered sensitive resistance transition, showing promising for fire safety and prevention.
In this work, hydroxyl-terminated polydimethylsiloxane (H-t-PDMS) nanocomposites reinforced by different contents of graphene oxide nanoribbons (GONRs) were prepared via a facile solvent-free ...process, and the mechanical properties of the H-t-PDMS/GONR nanocomposites were investigated and compared with the corresponding nanocomposites containing pristine carbon nanotubes (CNTs) or functionalized CNTs (f-CNTs). It was found that the GONRs with abundant functional groups showed good compatibility with the H-t-PDMS matrix at appropriate content: both good dispersion levels of the GONR sheets and strong GONR/matrix interfacial interactions were achieved at low filler content (≤0.5 wt%), although the GONR sheets showed obvious clusters in the matrix at relatively high content. Mechanical testing indicated that the incorporation of a low content of GONRs into the H-t-PDMS polymer resulted in significant improvements in both the tensile and tear strengths, e.g. about 158 and 284% at 0.5 wt% GONRs, respectively; and such reinforcement efficiency of the GONRs in the PDMS nanocomposites was much better than those of the corresponding CNTs or f-CNTs, even superior to those of other carbon nanofillers in previous PDMS-based nanocomposite systems. Based on the morphology and fracture surface analysis, the possible reinforcing mechanisms were discussed and clarified to understand the discrepancies in the mechanical properties of the nanocomposite systems studied.
In plants, cytosine DNA methylations (5mCs) can happen in three sequence contexts as CpG, CHG, and CHH (where H = A, C, or T), which play different roles in the regulation of biological processes. ...Although long Nanopore reads are advantageous in the detection of 5mCs comparing to short-read bisulfite sequencing, existing methods can only detect 5mCs in the CpG context, which limits their application in plants. Here, we develop DeepSignal-plant, a deep learning tool to detect genome-wide 5mCs of all three contexts in plants from Nanopore reads. We sequence Arabidopsis thaliana and Oryza sativa using both Nanopore and bisulfite sequencing. We develop a denoising process for training models, which enables DeepSignal-plant to achieve high correlations with bisulfite sequencing for 5mC detection in all three contexts. Furthermore, DeepSignal-plant can profile more 5mC sites, which will help to provide a more complete understanding of epigenetic mechanisms of different biological processes.
The epidermal growth factor receptor (EGFR) is a common driver of non-small cell lung cancer (NSCLC). Clathrin-mediated internalization (CMI) sustains EGFR signaling. AXL is associated with ...resistance to EGFR-tyrosine kinase inhibitors (TKIs) in EGFR-mutated (EGFR
) NSCLC. We investigated the effects of Leucine zipper downregulated in cancer-1 (LDOC1) on EGFR CMI and NSCLC treatment. Coimmunoprecipitation, double immunofluorescence staining, confocal microscopy analysis, cell surface labelling assays, and immunohistochemistry studies were conducted. We revealed that LDOC1 interacts with clathrin adaptors through binding motifs. LDOC1 depletion promotes internalization and plasma membrane recycling of EGFR in EGFR
NSCLC PC9 and HCC827 cells. Membranous and cytoplasmic EGFR decreased and increased, respectively, in LDOC1 (-) NSCLC tumors. LDOC1 depletion enhanced and sustained activation of EGFR, AXL, and HER2 and enhanced activation of HER3 in PC9 and HCC827 cells. Sensitivity to first-generation EGFR-TKIs (gefitinib and erlotinib) was significantly reduced in LDOC1-depleted PC9 and HCC827 cells. Moreover, LDOC1 downregulation was significantly associated (
< 0.001) with poor overall survival in patients with EGFR
NSCLC receiving gefitinib (
100). In conclusion, LDOC1 may regulate the efficacy of first-generation EGFR-TKIs by participating in the CMI of EGFR. Accordingly, LDOC1 may function as a prognostic biomarker for EGFR
NSCLC.
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