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The objective of this study was to compare the transformation of by-products between single dielectric barrier discharge (SDBD) and double dielectric barrier discharge (DDBD), to optimize the preparation of graphene-based catalysts and apply them in combination with DBD for volatile organic compound degradation. We compared the degradation performance of SDBD and DDBD, prepared, and characterized graphene-based catalysts. SEM, BET, XRD, and FTIR analyses showed that the morphologies and internal structures of the three catalysts were the best when 0.25 mL of [BMIM]PF6 was added. When MnO

The objective of this study was to compare the transformation of by-products between single dielectric barrier discharge (SDBD) and double dielectric barrier discharge (DDBD), to optimize the preparation of graphene-based catalysts and apply them in combination with DBD for VOCs degradation. The effect of three experimental conditions (initial concentration, output voltage, flow rate) on degradation rate, by-product transformation, and mineralization was investigated comparatively for SDBD and DDBD. Graphene oxide was prepared using the improved Hummers' method, and the optimal pathway of adding KMnO4 was selected. Graphene-based catalysts were synthesized using the ion-assisted hydrothermal method. The effect of the amount of 1-butyl-3-methylimidazolium hexafluorophosphate ([BMIM]PF6) on the preparation of three typical transition metal catalysts (Mn, Fe, and Ti) was studied. It was found that NO2 transformation rate of DDBD was higher than that of SDBD. The addition amount and interval time of KMnO4 affect the preparation of graphene oxide. [BMIM]PF6 dose of 0.25 ml, the preparation of three catalysts showed the best performance. MnOx/rGO exhibited superior performance in the degradation of benzene series, NO transformation, NO2 transformation, CO2 selectivity, and energy efficiency. FeOx/rGO exhibited superior performance for O3 transformation. Mn3O4 and Fe3O4 played a leading role in promoting the degradation of the benzene series and the transformation of by-products.

The distribution and availability of phosphorus (P) fractions in restored cut slope soil aggregates along altitude gradients were studied. We examined soil aggregates total phosphorus (TP), available phosphorus (AP) and phosphorus activation coefficient (PAC), and discovered that there was no significant difference in TP at four altitudes (p> 0.05), but there was a significant difference in AP at 3009 m, 3347 m and 3980 m (p< 0.05). At 3009 m, 3347 m and 3654 m, the AP accumulation in small size aggregates were more advantageous. Overall, PAC dropped steadily as aggregate size increased, as shown by PAC (3654 m)> PAC (3347 m)> PAC (3009 m)> PAC (3980 m) in altitudes. In all particle size soil aggregates, total inorganic phosphorus (TPi) > total organic phosphorus (TPo) > residual phosphorus (R-P) at 3009 m, 3347 m and 3654 m; TPo> TPi> R-P at 3980 m. Through correlation and multiple stepwise regression analysis, we concluded that active NaHCO3-Pi was the main AP source. It was suggested that more attention should be paid to the ratio of small particle size aggregates, so as to increase soil AP storage. At low (3009 m) and high altitude (3980 m), inorganic P fertilizer and P activator were added into soil to improve the activation ability of soil P and the AP supply, so as to promote the healthy development of slope soils ecosystem.

Diffuse optical tomography (DOT) is a non-invasive imaging modality that uses near-infrared light to probe the optical properties of tissue. In conventionally used deterministic methods for DOT inversion, the measurement errors were not taken into account, resulting in unsatisfactory noise robustness and, consequently, affecting the DOT image reconstruction quality. In order to overcome this defect, an extended Kalman filter (EKF)-based DOT reconstruction algorithm was introduced first, which improved the reconstruction results by incorporating a priori information and measurement errors to the model. Further, to mitigate the instability caused by the ill-condition of the observation matrix in the tomographic imaging problem, a new, to the best of our knowledge, estimation algorithm was derived by incorporating Tikhonov regularization to the EKF method. To verify the effectiveness of the EKF algorithm and Tikhonov regularization-based EKF algorithm for DOT imaging, a series of numerical simulations and phantom experiments were conducted, and the experimental results were quantitatively evaluated and compared with two conventionally used deterministic methods involving the algebraic reconstruction technique and Levenberg–Marquardt algorithm. The results show that the two EKF-based algorithms can accurately estimate the location and size of the target, and the imaging accuracy and noise robustness are obviously improved. Furthermore, the Tikhonov regularization-based EKF obtained optimal parameter estimations, especially under the circumstance of low absorption contrast (1.2) and high noise level (10%).

The direct conversion of biomass-derived ethanol to high-valued-added chemicals has attracted widespread attention recently due to the great economic and environmental advantages. In the present study, the conversion of bioethanol through the Guerbet coupling process was studied in a fixed-bed reactor for MgAlOx and ZnAlOx mixed-oxides supported Cu catalysts. From the results, Cu adding into the system greatly enhance the dehydrogenation of ethanol and increase the H-transfer in the course of Guerbet coupling process. Simultaneously, the porous mixed-oxides provide the acid-base property of the catalysts for intermediate transformation. Notably, for Cu/MgAlOx, the main product of ethanol conversion is butanol, but for Cu/ZnAlOx, the primary product is ethyl acetate. Characterizations such as X-ray diffraction (XRD), high-resolution transmission electron microscopy (HRTEM), X-ray photoelectron spectroscopy (XPS), in situ diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS) and CO2 temperature programmed desorption (TPD) were carried out to evaluate the structure and property of the catalysts. In combination with the catalytic performances with the characterization results, the synergistic catalytic effect between metal sites and acid-base sites were elaborated.

Synthesis of methyl methacrylate (MMA) via direct oxidative esterification from methacrolein (MAL) and methanol (MeOH) is of great significance in chemical industry. Supported gold catalysts are considered as one of the most potential candidates for this reaction but suffer from low activity and deactivation issue. Herein, by modulating the phase structure of hydroxyapatite (HAP) with different cations and anions, a synergic effect between gold and vanadate substituted hydroxyapatite (HVP) support for the synthesis of MMA was discovered. In direct oxidative esterification, among the evaluated catalyst/support systems, Au/HVP catalyst displays the best performance and unprecedented stability, which acts as one of the best-performing gold catalysts for oxidative esterification. Various characterizations such as X-ray diffraction (XRD), Raman spectra, scanning electron microscopy (SEM), transmission electron microscope (TEM) and in-situ diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS) of CO were conducted to disclose the structural and electronic property of the catalysts. Through in-situ FT-IR spectra of MAL and MeOH, the substrate was proved to be easily transformed on Au/HVP catalyst to ester. Besides, the presence of O2 was found to facilitate the adsorption of MAL. The results of temperature programmed desorption (TPD) of O2 implied that gold particles together with HVP support is promotional for activation and dissociation of oxygen, leading to good activity and high selectivity.

Fault diagnosis is of significance for ensuring the safe and reliable operation of machinery equipment. Due to the heavy noise and interference, it is difficult to detect the fault directly from the measured signal. Hence, signal processing techniques that can achieve feature extraction, signal denoising, and fault identification are the most common tools in the field. Blind deconvolution methods (BDMs), as one of the most classic methods, have been studied extensively and applied fully for machinery fault diagnosis. Up to now, plenty of publications about the studies and applications of BDMs for machinery fault diagnosis have been presented to academic journals, technical reports, and conference proceedings. This paper intends to survey and summarize the current progress of BDMs applied in machinery fault diagnosis, as well as provides a comprehensive review of BDMs from history to state-of-the-art methods and finally to research prospects. Firstly, the theoretical background and brief history of BDMs are introduced. Secondly, the modified BDMs are classified to review their basic principles. After that their merits and limitations as well as the performance analysis are summarized. Thirdly, the research and application on machinery fault detection using BDMs are overviewed. Finally, the prospects of BDMs in machinery fault diagnosis are discussed.

Sodium alginate (SA) aerogels have shown outstanding potential as regenerative adsorbent materials in the field of wastewater purification. Although SA aerogel adsorption has been demonstrated as a simple and resultful method for removing dyes, it has the limitation that it only transfers or concentrates dyes on the adsorbate, and does not actually degrade them. In this study, a three-dimensional (3D) MIL-125/g-C3N4/SA (CNTi-125@SA) composite aerogel with visible light photocatalytic activity was achieved for photocatalytic degradation of organic dyes, via in-situ growth, blending and freeze-drying strategy. The results demonstrate that CNTi-125@SA has high catalytic activity for the dyes rhodamine B (RhB), methylene blue (MB) and methyl orange (MO), and the degradation rate can reach up to 99.23%. Impressively, the composite aerogel exhibits excellent antibacterial ability, and the antibacterial rate can reach up to 100% against E. coli. In addition, the developed composite aerogel has excellent reusability and stability, and the degradation efficiency can still reach 85% after seven repeated tests. Owing to their high catalytic activity, excellent antibacterial properties and stability, the CNTi-125@SA composite aerogel can be potentially used in a wide range of dye wastewater purification.

Non-alcoholic fatty liver disease (NAFLD) is becoming a major health concern worldwide. Ilex hainanensis Merr. extract was proved to have anti-inflammation effect on NAFLD, and Ilexhainanoside D (IhD) and ilexsaponin ATo investigate the hepatoprotective effect of the combination of IhD and IsA (IIC) against NAFLD and discuss the potential mechanisms.Male C57BL/6 mice were fed a high-fat diet (HFD) to induce NAFLD and were treated with IIC (60, 120 or 240 mg/kg) for 8 weeks. Growth parameters, abdominal fat content, serum biochemical markers, hepatic lipid accumulation and insulin tolerance were assessed. Quantitative real-time PCR was used to determine the hepatic gene expression of TLR2, TLR4, TNF-α, IL-6, and IL-1β. Western blot analysis was performed to determine the expression of the epidermal tight junction proteins ZO-1 and occludin. Gut microbiota profiles were established via high-throughput sequencing of the V3-V4 region of the bacterial 16S rRNA gene.IIC significantly reduced the severity of NAFLD induced by HFD in a dose-dependent manner. IIC decreased the ratio of Firmicutes/Bacteroidetes, reduced the relative abundance of Desulfovibrio and increased the relative abundance of Akkermansia. The intestinal barrier was improved as evidenced by the upregulation of the expression of ZO-1 and occludin in the ileum. IIC thus reduced the entry of LPS into the circulation and decreased the hepatic gene expression levels of proinflammatory cytokines.This approach demonstrated the positive effects of IIC in a mouse model of NAFLD, indicating that it possibly acts by reducing inflammation and improving the intestinal barrier function.

An airdropped meteorological parameters measurement network (AMPMN) is introduced in this paper. AMPMN with star topology is composed of two kinds of nodes, sensor nodes and one relay node, all equipped with nRF905 radio frequency (RF) modules. A three-layer protocol is built on nRF905 in terms of its configuration. The RF configuration parameters and the payloads formats are set to enable the implementation of carrier sense multiple access with collision avoidance (CSMA/CA) or time division multiple access (TDMA) schemes through programming. The performances of two presented CSMA/CA schemes and one designed TDMA scheme are evaluated by simulation. Based on the simulation results and the difficulty of practical implementation, the CSMA/CA scheme without RTS/CTS is selected for AMPMN. AMPMN will be used in unmanned meteorological parameters measuring over hazard area.

The evolutionary model of the South China Sea (SCS) is discussed based on data from the Sanshui Basin which indicates the paleolatitude migration of South China. The results show that South China played a prevailing role in the evolution of the SCS, which has been basically formed by the southward migration, and later reversal, of the South China continent in the course of extension, faulting and breaking up in the south of South China during the Late Cretaceous to Miocene. The microcontinent fragments which are found scattered in the SCS today were separated there when South China migrated back. The Philippine Arc migrated northwards with Philippine Sea Plate until the Pliocene to form the east boundary of the SCS. The Indochina block only played a transitional boundary role.