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This paper aims to address the issue of environmental pollution resulting from marine oil spills by evaluating the oil adsorption performance of commonly used fence materials. Conventional oil adsorption materials exhibit limited rates and capacities for oil adsorption. Existing methods have proven insufficient in meeting the requirements for efficient and rapid oil–water separation. A new oil-absorbing barrier was developed by utilizing high oil adsorption resin as the primary material and hydroxypropyl methyl cellulose (HPMC) as the binder, leveraging the exceptional oil adsorption and hydrophobic properties of P(BMA-SMA-St)/MIL-101(Fe) resin. The oil-absorbing fence was characterized using scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR) and thermogravimetric analysis (TGA). The oil adsorption rates of carbon tetrachloride, toluene, diesel and gasoline by the oil adsorption fence with 25 g/L resin content were 101.26 g/m2, 68.12 g/m2, 35.19 g/m2, and 46.69 g/m2, respectively. After 120 h of UV irradiation, the coating's oil absorption capacity remained nearly unchanged, and it demonstrated outstanding mechanical, chemical, and wear resistance. As a result, the oil adsorption fence possesses the capability to rapidly absorb oil from the water's surface during the process of containing oil pollution, leading to positive social and economic impacts. [ABSTRACT FROM AUTHOR]

The low thermal conductivity and liquid-phase leakage of phase change materials seriously hinder their large-scale applications. Porous materials have been identified as an effective way to address the leakage and provide a thermally conductive network. Therefore, we designed an expanded graphite-based multifunctional composite phase change thermal storage materials for personal thermal management and antimicrobial in medical protection. Expanded graphite (EG) was used as the matrix, silver nanowires (Ag NWs) as the functional enhancement materials, and n-octadecane (OD) as the thermal storage materials. OD and Ag NWs were adsorbed in the porous structure of EG by vacuum-assisted impregnation. Finally, EG/Ag NWs/OD were combined with non-woven fabrics (N) by one-step hot pressing method to obtain EG/Ag NWs/OD-N composite with excellent comprehensive performance. With the mass ratio of EG to Ag NWs of 13:7, EG/Ag NWs/OD-N exhibited a thermal conductivity of 2.0130 W m−1 K−1, which was improved by 1070.3% compared with pure OD. EG/Ag NWs/OD-N has a melting enthalpy of 137.85 J·g−1 and a crystallization enthalpy of 128.97 J·g−1. In addition, EG/Ag NWs/OD-N display great antibacterial properties, thermal cycling stability, shape stability, and cycling persistence and showed excellent temperature control in protective clothing applications, offering great potential for large-scale applications. [ABSTRACT FROM AUTHOR]

Polyimide (PI) has been widely used to manufacture flexible films in aerospace, electronics and other fields because of its flexibility, thermal resistance, etc. However, the thermal conductivity of PI is relatively low, restricting the wider applications of PIs. This review discusses the research progress during recent five years in the preparation of filled-type PI composites with high thermal conductivity and flexibility. In addition, this review introduces four types of fillers, including boron nitride, graphene (or graphite oxide), carbon nanotubes and carbon nitride, as well as four popular preparation methods, the arrangement and surface modification of fillers, the microstructure design of composites and the synergistic effect of different fillers, and explicitly explains the different action mechanisms between them. These methods provide suggestions to balance the relationship amongst thermal conductivity, flexibility and mechanical properties of preparing filled-type PI composites. In addition, this article also introduces the current application status and future prospects of PI composite materials in advanced materials. [ABSTRACT FROM AUTHOR]

Due to the excellent performance of deep learning, more and more image denoising methods based on convolutional neural networks (CNN) are proposed, including dilated convolution method and multi-scale convolution method. A fundamental issue is how to obtain multi-scale information and to recover the image detail. In order to solve the issue, we present a multi-scale dilated residual convolution network (MDRN), which has a multi-scale feature extraction block and dilated residual block. The multi-scale feature extraction block, making full of the multi-scale information, is presented by incorporating multiple-scale pixel shuffle downsampling, which can extract salient features from input images. At the same time, the dilated residual block expands the receptive field and can effectively utilize the global image information. Extensive experimental results on both the synthetic and real-world noisy images show that our method is effective and surpasses the state-of-the-art denoising methods in terms of both quantitative and qualitative evaluations. [ABSTRACT FROM AUTHOR]

Electricity-generating bacteria as biocatalysts for microbial fuel cells (MFCs), their species, and power generation performance determine the pollution control and power generation performance of MFCs. And there are few studies on the types and performance of electricity-generating bacteria isolated from oily sludge microbial fuel cells. For improving the power generation performance of oily sludge MFCs, an electricity-generating bacterium was isolated from the oily sludge. More importantly, the adaptability of nitrogen to phosphorus ratio, temperature, and pH of the electricity-generating bacteria were adjusted by a controlled variable method. The results of this study showed that the electricity-generating bacterium was identified as Bacillus cereus, with a rod-shaped cell, about 0.5–1.0 μm in length. The optimal nitrogen-phosphorus ratio, temperature, and pH of MFCs were 4.67:1, 25 ℃, and pH = 7, respectively. Its maximum power density, COD, and oil removal rate was up to 65 mW·m−3, 90.51%, and 87.76%, respectively. The study of this functional bacterium will provide beneficial assistance for the improvement of oil removal and power generation performance of oily sludge MFCs. [ABSTRACT FROM AUTHOR]

In order to keep the microcapsules intact during transportation and storage, the mechanical properties of the microcapsules need to be enhanced, and therefore, we innovatively attached the oxidized carbon nanotubes (CNTs) to the surface of phenolic resin, and CNTs/phenolic resin microcapsules were successfully synthesized by in situ polymerization method. The tests showed that CNTs had been successfully compounded with phenolic resin, and CNTs can effectively improve the mechanical properties of microcapsules with a 16.37% increase in maximum rupture load. This research result was expected to provide positive scientific ideas to solve the problem of early fracture in the airtight wall of the goaf. [ABSTRACT FROM AUTHOR]

In order to solve the problem of demulsification of Liaohe heavy oil W/O emulsion, phenolamine resin initiator was synthesized based on p-trifluoromethyl phenol in this paper. Polyether product was synthesized by block polymerization technology, and then toluene diisocyanate (TDI) was added for crosslinking modification, thus synthesizing a new fluorinated block polyether demulsifier called reticulated branched fluorinated (RBF). Apart from that, the structure of fluorinated polyether demulsifier was characterized by FTIR spectrum, and the surface activity of fluorinated polyether demulsifier was determined by measuring the surface tension and interfacial tension, and the thermogravimetric analysis (TGA) of RBF demulsifier was also determined. The demulsification and dehydration experiment of Liaohe crude oil emulsion was carried out. The microscopic demulsification process was analyzed and the demulsification mechanism was discussed. The experimental results showed that the synthesized RBF series fluorinated polyether demulsifier had excellent demulsification performance on Liaohe water-in-oil (W/O) emulsion. Such a result was attributed to the reticulated multi-branched structure which increased the ability of demulsifier to replace the interfacial film, so the new interfacial film was easy to break to gather with other water droplets, thus resulting in the destruction of the W/O emulsion stabilization system. When TDI dosage was 4% of polyether demulsifier mass, demulsification temperature was 60 ℃, and demulsifier dosage was 50 mg/L, the dehydration rate of RBF4 reached 95.64%, which was about 18% higher than that of demulsifier LX21. This paper provides a new type of high-efficiency demulsifier to solve the demulsification problem of heavy oil W/O emulsion in Liaohe Oilfield. [ABSTRACT FROM AUTHOR]

The author innovatively proposed a block polyether demulsifier. p-Tert-butylphenol amine resin was synthesized by the reaction of p-tert-butylphenol with formaldehyde and tetraethylenepentamine, which was used as an initiator to polymerize with ethylene oxide (EO) and propylene oxide (PO) to generate four multi-branched block polyether demulsifiers with different EO ratios. The demulsifier was characterized by infrared spectroscopy, Physica MCR 301 rheometer, and cloud point method. Then, 4,4′-diphenylmethane diisocyanate (MDI) and (Epichlorohydrin) POCL were used in the polyether demulsifier for oil-soluble and water-soluble modification. Finally, it was found that the oil-soluble emulsifier 159C has excellent demulsification performance and the dehydration rate is 86.2%. [ABSTRACT FROM AUTHOR]

To improve the safety of cryclotrimethylenetrinitramine (RDX), a novel method for the improvement of nano-energetic materials was reported in our research. Based on the mature microcapsule technology, nano-energetic materials are firstly fabricated by using RDX as core material and poly methyl metharylate (PMMA) as shell material via an emulsion polymerization method. The RDX/PMMA nano-composites were characterized by scanning electron microscopy (SEM), Fourier-transform infrared (FT-IR) spectra, X-ray diffraction (XRD), differential scanning calorimetry (DSC) and impact sensitivity test, respectively. The SEM results indicated successful coating of the wall material PMMA on the surface of the core RDX, and the resultant particles by emulsion polymerization were regular solid spherical particles with smooth surface and dense coating layer, more importantly, it exhibits a very uniform particle size distribution with a narrower grain size. The XRD and FT-IR analyses did not show any change in the crystal structure after coating, thus indicating that PMMA could not change the crystal structure of RDX. Moreover, the characteristic height H50 of RDX/PMMA microspheres increased from 24.3 to 39.7 cm, significantly improving the safety performance. According to the DSC analysis, the Tb after core–shell coating increased by about 2 °C, and the Ea increased by 19.07 kJ mol−1, revealing desirable thermal stability. It is obvious that the emulsion polymerization method is an effective desensitization technique to prepare core–shell composite particles for RDX. [ABSTRACT FROM AUTHOR]

Microbial fuel cell (MFC) technology is a simple way to accelerate the treatment of the oily sludge which is a major problem affecting the quality of oil fields and surrounding environment while generating electricity. To investigate the oil removal and the characteristics of changes in the composition of bacteria, sediment microbial fuel cells (SMFCs) supplemented with oily sludge was constructed. The results showed that the degradation efficiency of total petroleum hydrocarbon (TPH) of SMFC treatment was 10.1 times higher than the common anaerobic degradation. In addition, the degradation rate of n-alkanes followed the order of high carbon number > low carbon number > medium carbon number. The odd–even alkane predominance (OEP) increased, indicating that a high contribution of even alkanes whose degradation predominates. The OUT number, Shannon index, AEC index, and Chao1 index of the sludge treated with SMFC (YN2) are greater than those of the original sludge (YN1), showing that the microbial diversity of sludge increased after SMFC treatment. After SMFC treatment the relative abundance of Chloroflexi, Bacteroidia and Pseudomonadales which are essential for the degradation of the organic matter and electricity production increased significantly in YN2. These results will play a crucial role in improving the performance of oily sludge MFC. [ABSTRACT FROM AUTHOR]

To improve the safety of ammonium nitrate explosives, the melamine urea-formaldehyde resin (MUF resin) was selected for the preparation of three typical nitramine explosives (cyclotetramethylenetetranitramine, HMX; cryclo-trimethylenetrinitramine, RDX; and hexanitrohexaazaisowurtzitane, CL-20) based green polymer-bonded explosives (GPBXs) via interfacial polymerization. Meanwhile, the corresponding composite particles prepared by physical mixing and drying bath methods were studied and compared. The particle morphology, crystal structure, thermal stability, and safety performance of the resultant composite particles were characterized by scanning electron microscopy (SEM), powder X-ray diffraction (XRD), Fourier transform infrared (FT-IR) spectra, differential scanning calorimeter (DSC), and impact sensitivity test, respectively. SEM results showed that MUF was successfully coated on the surface of the three explosives, and different composite particles prepared by the same method have their own unique characteristics. Such effect is attributed to the resin's ability to isolate and buffer external stimuli. It is obvious that the interfacial polymerization is an effective desensitization technique to prepare core-shell composite particles for explosives. [ABSTRACT FROM AUTHOR]

In this work, we have investigated two kinds of charge trapping memory devices with Pd/Al2O3/ZnO/SiO2/p-Si and Pd/Al2O3/ZnO/graphene oxide quantum-dots (GOQDs)/ZnO/SiO2/p-Si structure. Compared with the single ZnO sample, the memory window of the ZnO-GOQDs-ZnO sample reaches a larger value (more than doubled) of 2.7 V under the sweeping gate voltage ± 7 V, indicating a better charge storage capability and the significant charge trapping effects by embedding the GOQDs trapping layer. The ZnO-GOQDs-ZnO devices have better date retention properties with the high and low capacitances loss of ∼ 1.1 and ∼ 6.9%, respectively, as well as planar density of the trapped charges of ~ 1.48 × 1012 cm− 2. It is proposed that the GOQDs play an important role in the outstanding memory characteristics due to the deep quantum potential wells and the discrete distribution of the GOQDs. The long date retention time might have resulted from the high potential barrier which suppressed both the back tunneling and the leakage current. Intercalating GOQDs in the memory device is a promising method to realize large memory window, low-power consumption and excellent retention properties. [ABSTRACT FROM AUTHOR]