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Hyperglycemia-induced inflammation and subsequent endothelial injuries ultimately lead to the pathogenesis of cardiovascular diseases associated with high mortality, such as atherosclerosis. Maslinic acid (MA) is a phytochemical with anti-inflammatory activity. However, it remains unknown whether it can inhibit diabetes-associated cardiovascular inflammation. The present study aimed to determine the effect of MA on high glucose-induced endothelial inflammation and apoptosis in human umbilical vein endothelial cells (HUVECs) and to explore the underlying mechanism.HUVECs were treated with high glucose to induce inflammation and apoptosis. Apoptosis was determined by flow cytometry. CCK-8 assay was used to examine cell viability. Production levels of cytokines were detected by quantitative realtime PCR (qPCR) and ELISA. Protein expression levels and signaling pathways activation were detected by Western blotting. RNA immunoprecipitation and qPCR were used to determine the NMA promoted the recruitment of RNA demethylase ALKBH5 to TXNIP mRNA, and subsequently enhanced its m6A demethylation. By this means, MA decreased the stability of TXNIP mRNA and downregulated its expression level. Subsequently, reactive oxygen species (ROS) and production of pro-inflammatory cytokines, including TNF-α, IL-6 and IL-1β, were inhibited. And high glucose-induced apoptosis in HUVECs was inhibited by MA.MA ameliorates high glucose-induced endothelial inflammation and injury, serving as a new potential therapeutic application for protecting against diabetes-associated atherosclerosis and other inflammatory diseases.

La3+- or Yb3+-doped TiO2 supported on the surface of reduced graphene oxide were fabricated by adsorbed-layer nanoreactor synthesis (ANS) coupling with a solvothermal treatment to extend photocatalysis application in the advanced treatment of simulated wastewater with high salt concentration. Results showed that La3+ or Yb3+ could distribute in the TiO2 lattice, only in ANS preparation with graphene oxide as the carrier, to replace Ti4+ during the solvothermal treatment, thus introducing TiO2 mixed-crystal and heterojunction structures in the catalysts. La3+ or Yb3+ caused lattice distortion structures and anionic vacancies in the TiO2 lattice. The anionic vacancies (oxygen vacancies) might generate Ti3+ in catalysts, thus enhancing visible-light response, due to impurity levels introduced by La3+ or Yb3+. As the strong adsorption capability of the catalyst for phenol was not interfered by salt ions in the simulated wastewater, the catalysts could efficiently degrade phenol. The highest removal rate of phenol was approximately 90%.

This study aimed to expand the visible-light response of commercial titanium dioxide (TiO2, P25) photocatalysts using surface modification by hydrothermal reduction with various reductants to improve their photocatalytic performance for phenol degradation in high-salinity wastewater under room visible-light irradiation. Structure characterization results for different reduced P25 photocatalysts show that hydrothermal reduction cannot only generate disordered crystalline shell–core structures on the catalyst surface but also introduce several Ti3+ into the photocatalysts, facilitating the visible-light response of reduced P25. The moderate conditions of hydrothermal reduction not necessarily destroyed the inner crystalline structure of P25 to form amorphous TiO2 as deep trapping sites for photogenerated charges, different from the results for the reduced P25 obtained by hydrogeneration reduction (P25–H2). Therefore, the reduced P25 obtained by hydrothermal reduction with Zn as reductant featured a slightly higher photocatalytic activity for phenol than P25–H2 under visible-light irradiation, although P25–H2 exhibited a smaller Eg and stronger visible-light absorbance. The highest removal rate for phenol of reduced P25 within 5 h reached up to 87.5% and considerably exceeded that of P25–H2 (60.0% removal rate of phenol). Apart from the reduction capability of metals, the solubility of the corresponding metal hydroxide plays a major role in P25 reduction in the hydrothermal process. The water-insoluble metal hydroxide precipitates on the metal surface and inhibits the reduction between metal and P25, thereby decreasing the photocatalytic performance of reduced P25 for phenol excited by room visible-light.

In this study, piezoelectric zinc oxide (ZnO) thin film was deposited on the Pt/Ti/SiNx/Si substrate to construct the FBAR device. The Pt/Ti multilayers were deposited on SiNx/Si as the bottom electrode and the Al thin film was deposited on the ZnO piezoelectric layer as the top electrode by a DC sputtering system. The ZnO thin film was deposited onto the Pt thin film by a radio frequency (RF) magnetron sputtering system. The cavity on back side for acoustic reflection of the FBAR device was achieved by KOH solution and reactive ion etching (RIE) processes. The crystalline structures and surface morphologies of the films were analyzed by X-ray diffraction (XRD) and field emission scanning electron microscope (FE-SEM). The optimized as-deposited ZnO thin films with preferred (002)-orientation were obtained under the sputtering power of 80 W and sputtering pressure of 20 mTorr. The crystalline characteristics of ZnO thin films and the frequency responses of the FBAR devices can be improved by using the rapid thermal annealing (RTA) process. The optimized annealing temperature and annealing time are 400 °C and 10 min, respectively. Finally, the FBAR devices with structure of Al/ZnO/Pt/Ti/SiNx/Si were fabricated. The frequency responses showed that the return loss of the FBAR device with RTA annealing was improved from −24.07 to −34.66 dB, and the electromechanical coupling coefficient (kt2) was improved from 1.73% to 3.02% with the resonance frequency of around 3.4 GHz.

Commercial TiO2 photocatalyst P25 was first used as a support to prepare Ag-deposited catalysts by adsorbed-layer nanoreactor synthesis (ANS). Characterizations were performed by UV–vis diffuse reflectance spectroscopy, TEM, XRD, XPS, PL spectroscopy, and photo-electrochemical analysis. Results showed that Ag nanoparticles with size of less than 10 nm distributed very homogeneously on the TiO2 surface. The adsorption layer on the TiO2 surface acting as a nanoreactor led to tight interaction between quantum-size Ag particles and the TiO2 surface, thereby introducing staggered heterojunction structures into the catalysts. The heterojunction between quantum-sized Ag particles (less than 10 nm) and TiO2 led to the surface plasmon resonance effect and strong visible-light response of catalysts. Ag deposition further caused distortions in TiO2 crystal lattices. Both the heterojunction and TiO2 lattice distortions enhanced the separation efficiency of charge carriers, which improved the photocatalytic activity for phenol in seawater under visible-light irradiation. The catalyst exhibited high stability and reusability after six cycles because of its morphological stability.

The main objective of mine ventilation network optimization studies is to develop a reasonable method for ventilation system control that minimizes the total cost of mine ventilation. The fundamental principles for ventilation network optimization are discussed, and a multi-objective optimization model is established from the viewpoint of total cost. Furthermore, an optimization algorithm based on the airflow asymptotic calculation is presented by the hierarchical analysis of objective functions and analysis of the structure characteristics of a ventilation network. In the proposed approach, the regulated branches are determined by the directed path matrix; the optimal solution is obtained by airflow asymptotic calculation using the existing software for ventilation network analysis, and it does not need to solve the large-scale nonlinear programming problem. The results of example analysis validated the reliability of this approach.

The seawater system is a typical salt water system. A catalyst should overcome the disturbance from the salt ions for an efficient photodegradation of organic pollutants in the seawater system. Commercial photocatalysts (P25) and La3+-doped SiO2–TiO2 prepared using adsorbed-layer nanoreactor synthesis (ALNS) were first used for photodegrading different initial concentrations of phenol in seawater under weak UV light irradiation. The weak adsorption capacities for phenol and the hydrophilic surfaces of the two photocatalysts could not overcome the disturbance of salt ions and thus showed low photocatalytic activities. Based on this, graphene oxide (GO) was used as a support to prepare TiO2 and La3+-doped TiO2 using ALNS. The solvothermal treatment with alcohol was used as a solvent for both TiO2 crystallization and GO reduction. Results showed that TiO2 nanoparticles with sizes

Local ventilation using a fan and duct at a heading face is one of the most important ventilation practices in underground mining operations, there have been many studies on this topic. Almost all the researches are assuming that the ventilation system is operating under normal circumstance. But this is not always true, the ventilation system does stop suddenly due to unforeseeable reasons. It is essential that methane emissions and concentration at the heading face in case of sudden ventilation stops be understood. were examined by model experiments and computer simulations. The followings were found for the ventilation stop incident. The heading face will be dangerous by the methane gas increase within 10 min if ventilation stops. Methane concentration in a downward heading face decreases only 15% relatively compared with the horizontal condition. Methane will accumulate in short time, and become extremely high risk in an upward heading faces. The methane concentration decreases to some degree if the gas is sucked by an air mover.

Thermal conductivity of rock is a basic characteristic concerning the safety and thermal environment in mines. However, considerable preparation work and time are necessary for the measurement by a typical measuring method. Although, a new measuring method based on heat conduction theory of spherical heat source was developed, an easy and rapid measuring method to measure in situ thermal conductivity has yet to be developed. The method was first theoretically examined by a computer simulation and several measuring devices were made based on the result for verification. The test using the devices was conducted for various materials in a laboratory. Comparative measurement using another device based on line heat source currently used was also conducted. In addition, thermal conductivities of rock in a mine were measured. As a result, it has been found that the in situ measurement by the new method can be done easily and rapidly with acceptable accuracy.

By applying non-equilibrium Green's functions in combination with density-functional theory, we investigate electronic transport properties of C60 coupled to carbon nanotubes and Li electrodes. The results show that electronic transport properties of CNT–C60–CNT and Li–C60–Li systems are completely different. Nonlinear I–V characteristic, varistor-type behavior and negative differential resistance (NDR) phenomenon are observed when electrodes are carbon nanotubes. We discuss the mechanism of I–V characteristics of CNT–C60–CNT systems in details. Our results suggest conductance, energy level of Frontier molecular orbitals, energy gap between HOMO and LUMO, the coupling between molecular orbitals and electrodes are all playing critical roles in electronic transport properties.

Density functional calculations have been performed on initial copper deposition and its growth over ZnO nonpolar (1010) and (1120) surfaces. On (1010), our results demonstrate that copper atoms first interact with dangling bonds or bonding orbital above ZnO. As the deposition increases, they form a zigzag structure along U-shaped gaps, then the surface layers fluctuate, and finally they develop into three-dimensional clusters on the surface. On (1120), we show that copper atoms also initially interact with dangling bonds. As the deposition increases, however, they form strips in the U-shaped gaps, then surface layers, and finally two-dimensional cages. In either case, our results fit well with experimental observations. Our results also indicate that the bonding of copper with ZnO substrate and that among adsorbed copper atoms are competitive, in the sense that copper (3d104s1) has limited bonding ability. Further, our results indicate that some copper atoms that strongly interact with ZnO become pos...

We report a soluble pentacene derivative, 6,13-bis(2-(trimethylsilyl)ethynyl)pentacene, can be used for efficient extraction of metallic single-walled carbon nanotubes (SWCNTs), which is proven by resonance Raman spectroscopy (RRS), Vis–NIR absorption spectroscopy and conductivity measurements. RRS studies reveal that the separation is solvent-dependent and is more efficient for small diameter tubes. Theoretical simulation suggests that the adsorption of pentacene on (7, 7) metallic SWCNT is about 34% more favorable than that on (13, 0) semiconducting SWCNT. This work provides a new direction in seeking reagents to facilitate high efficiency and nondestructive separation of metallic and semiconducting SWCNTs.

In this work, we demonstrate a simple and reliable method for selectively separating single wall carbon nanotubes (SWNTs). This method is based on a preferable adsorption of linear polynuclear aromatic dyes on metallic SWNTs. With different adsorption amount of soluble dyes, the metallic and semconducting SWNTs show different solubility in solvents, hence can be separated. The types of the obtained SWNTs and the separative efficiency using different dyes have been studied using Raman spectroscopy. It was found that the polynuclear molecules with more benzene rings show higher selectivity. Meanwhile, the separative efficiency is also sensitive to the choice of solvents.

Systematic studies on noncovalent functionalization of multiwalled carbon nanotubes (MWNTs) were assisted by a series of aromatic dye molecules with different structural characteristics. The effects of molecular structure on the affinities of different dyes to the MWNTs were evaluated. Two main factors have been found to play the key roles for the dye–MWNTs interactions, which are molecular geometry and charge. It was found that molecules with planar structures and high charge load are favored for the adsorption. This work not only demonstrates a simple and effective method to functionalize the sidewalls of carbon nanotubes but also give insight to the adsorption mechanism between the carbon nanotubes and aromatic molecules.

The mechanism of thiophene cracking catalyzed by Bronsted acidic zeolites was computed at the level of B3LYP density functional theory. It was found that this catalytic reaction involves two major steps: (1) protonation of thiophene associated with an electrophilic aromatic substitution to another thiophene in a concerted way to form 2-(2,5-dihydrothiophen-2-yl) thiophene, and (2) C S bond dissociation in 2,5-dihydrothiophene promoted by further protonation. The intermediate, 4-mercapto-1-(thiophen-2-yl)but-2-en-1-ylium, was found to have a CH 2 group close to a C C bond and a SH group, in agreement with the experimental findings. A strong stabilization effect of the zeolite framework on the transition states was found by embedding the 5T cluster into the larger 34T and 56T clusters. The rate-determining step is the electrophilic aromatic substitution.

Support vector machine (SVM) is used to predict the enthalpies of formation at 298 K [Formula: see text] for 261 molecules based on B3LYP/6-311g (3df,2p) results. With data randomly separated into two parts: 195 for training set and 66 for test set, the resulting mean absolute deviation (MAD) and maximum deviation (MD) for training set are 1.51 kcal/mol and 9.23 kcal/mol (correlation coefficient R = 0.9995), and for test set they become to 1.78 kcal/mol and 7.31 kcal/mol (R = 0.9990). The result is improved according to G2 method.

The first examples of novel bowl-shaped tribenzotriquinacenes (TBTQs) bearing three dithiametacyclophane units within their arene peripheries are reported. The synthesis is based on a C-3v-symmetrical hexakis(chloromethyl)tribenzotriquinacene as the key intermediate and yields the inter-ring metacyclophane-type macrocyclization instead of the intra-ring orthocyclophane-type cyclocondensation. Multiple nucleophilic substitution of the same key intermediate leads to a number of other new 6-fold functionalized tribenzotriquinacenes, some of which may be of interest as readily accessible building blocks for the construction of novel bowl-shaped organic networks. The molecular structures of the novel tris(dithiametacyclophanes) and of the hexakis(chloromethyl)- and hexakis(hydroxymethyl)tribenzotriquinacenes have been determined by X-ray analysis and interesting host/guest aggregation and torsional effects in the solid state are discussed.

Highly ordered iron arrays of nanowires with different diameters have been prepared by the electrochemical deposition method, with the intention of studying magnetic texture in this system. Crystal texture with the [110] direction along the axis of the nanowires is demonstrated by x-ray diffraction measurements. The orientation of the magnetic moments is along the long axis of the nanowire, a result deduced from the transmission Mossbauer spectra of the as-prepared sample and the remanent states. However, as the intensity of the second and fifth lines is larger in conversion electron Mossbauer spectra than that in transmission Mossbauer spectra for the same diameter samples, the orientation of the magnetic moments appears to deviate from the axis more at the ends than that in the middle of the nanowires. On increasing the nanowire diameter, the magnetic texture becomes weaker. Large coercive force can be found for the small diameter samples when the external magnetic field is applied along the long axis of the nanowires.

An airflow distribution in an ventilation network is changed when an airway resistance in the network is changed by an airflow regulator damaging or an airway collapsing. The occurrence of an abnormal airway will be found by analysing the airflow changes created in the network, if airflows are monitored in several airways. This paper describes the newly developed methods to locate an abnormal airway and estimate the changed value of resistance by means of analysis of the measured airflow data.In the first method the ventilation network is analyzed, measured airflow data being introduced, and the pressure distribution thereby obtained are examined, which enables us to detect the place creating an abnormal airflow resistance and to evaluate the change.The second method utilises a data base of airflow distributions which are calculated in advance for various combination of network resistances.In the case of the occurence of an abnormal airway, it is generally impossible to get the accurate airflow distribution by an ordinary method for ventilation analysis method, because the value of the changed resistance there is unknown. However, it is proved that the correct airflow distribution can be obtained, if measured airflow data are introduced in the ventilation network analysis method proposed in this paper.

Using first-principles density functional theory calculations, various junction models constructed from different carbon nanotube and graphene nanoribbon units via covalent linkage have been envisioned. These models consist of linear, T- and H-shaped junctions within the connection modes between carbon nanotube and graphene nanoribbon units. The electronic transport properties of different junctions have been systematically investigated by using the non-equilibrium Green's function. The simulation results suggested that the proposed models are promising for future applications in novel nanoelectronics.

A systematic investigation of the electronic transport properties of Haeckelite nanotubes using ab initio calculation is presented. The Haeckelite nanotube is coupled with Haeckelite nanotubes and bulk Au electrodes, respectively. Negative differential resistance and nonlinear conduction phenomena have been observed in the simulated I–V curves. Our results suggest that this behavior is attributable to the band mismatch between left and right electrodes, which implies that some intriguing electronic transport characteristics could be realized by using nanoscale electrodes.