Search

LaZSM-5 zeolite was synthesized by the in situ method and used as catalysts to catalyze the synthesis of rosin glyceride. As a comparison, ZSM-5 was also synthesized and used as catalysts to catalyze the synthesis of rosin glyceride. The synthesized ZSM-5 and LaZSM-5 zeolite catalysts were characterized and analyzed. The experimental results showed that the in situ synthesis of LaZSM-5 made La into the skeleton of ZSM-5 zeolite and increased the amount of Lewis acid on the LaZSM-5 zeolite. Also, Lewis acid was the key to liquid-phase esterification reaction. Compared with ZSM-5 zeolite, LaZSM-5 zeolite contributed to a higher yield and better stability as a catalyst for the synthesis of rosin glycerides.

Electrode materials with high volumetric capacity are highly desired to improve the energy storage performance for the next generation supercapacitor. The loading density of active materials and potential window are the two keys to realizing the maximization of volumetric capacity. Herein, carbon aerogel microspheres (CAMs) with uniform spherical structure and high loading density are prepared by an emulsion polymerization without freeze/supercritical drying step. The CAMs are further treated with H3PO4, which not only optimize their pore structure for facilitating ion diffusion but also introduce phosphorus species to carbon skeleton for blocking active oxidation sites. Owing to the high loading density and the suppressed formation of unstable oxygen species by phosphorus, the optimal sample shows a good volume energy density of 48.1 Wh L−1 under a high applied potential difference of 3.3 V in 1M TEABF4/PC electrolyte. Our work presents a new direction for the developing of high volumetric energy density supercapacitors.

Mild pyrolysis is one of the precombustion mercury control techniques. Mercury removal efficiency through mild pyrolysis has close relation with the weak thermal stability of mercury in coal. The t...

As a renewable biomass product, starch is a fantastic source for preparing various advanced carbon materials. But starch shows poor thermal stability. Its original spherical morphology tends to be ...

Phosphorus doping is an effective approach to tailor the surface chemistry of carbon materials. In this work, two-dimensional graphene, as a simplified model for all sp2 hybrid carbon allotropes, is employed to explore the surface chemistry of P-doped carbon materials. Thermally reduced graphene oxide, with abundant residual oxygen functionalities, is doped by phosphorus heteroatoms through H3PO4 activation, followed by passivation in an inert atmosphere. The structural evolution of the phosphorus species in the carbon lattice during the thermal treatment is systematically studied by Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy, X-ray diffraction, and Raman spectroscopy with the assistance of first-principles calculations. The C3-P═O configuration is identified as the most stable structure in the graphene lattice and plays a key role in stabilizing the electrochemical interface between the electrode and electrolyte. These features enable an electrode based on P-doped graphene to exhibit an enlarged potential window of 1.5 V in an aqueous electrolyte, a remarkable improved cycling stability, and an ultralow leak current. Therefore, this contribution provides insights for designing phosphorus-doped carbon materials toward electrocatalysis, energy-related applications, and so forth.

The photocatalyst, with high photocatalytic performance and cycling stability in visible light, as well as superior adsorption capability, was highly desired for degradation of organic pollutants i...

The exploration of renewable, cost-effective, and environmentally friendly electrode materials with high adsorption, fast ion/electron transport, and tunable surface chemistry is urgently needed for the development of next-generation biocompatible energy-storage devices. In recent years, biomass-derived carbon electrode materials for energy storage have attracted significant attention because of their widespread availability, renewable nature, and low cost. More importantly, their inherent uniform and precise biological structures can be utilized as templates for fabricating electrode materials with controlled and well-defined geometries. Meanwhile, the basic elements of biomass are carbon, sulfur, nitrogen, and phosphorus. The special naturally ordered hierarchical structures as well as abundant surface properties of biomass-derived carbon materials are compatible with electrochemical reaction processes such as ion transfer and diffusion. To date, a series of novel porous carbon materials with different dimensions have been prepared by various methods using biomass as the raw material, which is an important field in the fabrication of supercapacitor electrode materials. Herein, we summarized recently reported biomass-derived carbon materials with one-dimensional, two-dimensional, and three-dimensional structures and their applications as carbon-based electrode materials for supercapacitors. Finally, the current challenges and future perspectives of the carbon-based electrode materials with respect to the supercapacitor's performance were closely highlighted.

BiOBr photocatalysts were prepared by a facile one-pot solvothermal approach with cetyltriethylammnonium bromide and bismuth nitrate as the precursors in ethanol, ethylene glycol, tert-butanol, benzyl alcohol, and 2-methoxyethanol solvents, respectively. The morphology, pore structure, specific surface areas, and optical properties of BiOBr are solvent dependent, and a possible formation mechanism for the thin BiOBr nanosheets prepared in benzyl alcohol with higher exposed (001) facet is proposed. BiOBr prepared in benzyl alcohol exhibited superior photocatalytic activity for the photodegradation of Rhodamine B under visible light irradiation, and the high photocatalytic performance can be ascribed to the nanosheet structure and increased number of exposed (001) surfaces. The photogenerated holes h+ and superoxide radical anions ˙O2− have a major effect on RhB degradation via photocatalysis and dye self-sensitization. This work provides a simple method to prepare BiOBr with a nanosheet structure and more exposed (001) surfaces, which motivates its practical application for the exploitation and utilization of solar energy.

Cistanche tubulosa is a type of Chinese herbal medicine and exerts various biological functions. Previous studies have been demonstrated that Cistanche tubulosa phenylethanoid glycosides (CTPG) exhibit antitumor effects on a variety of tumor cells. However, the antitumor effects of CTPG on HepG2 and BEL-7404 hepatocellular carcinoma (HCC) cells are still elusive. Our study showed that CTPG significantly inhibited the growth of HepG2 and BEL-7404 cells through the induction of cell cycle arrest and apoptosis, which was associated with the activation of MAPK pathways characterized by the up-regulated phosphorylation of p38, JNK, and ERK1/2 and mitochondria-dependent pathway characterized by the reduction of mitochondrial membrane potential. The release of cytochrome c and the cleavage of caspase-3, -7, -9, and PARP were subsequently increased by CTPG treatment. Moreover, CTPG significantly suppressed the migration of HepG2 through reducing the levels of matrix metalloproteinase-2 and vascular endothelial growth factor. Interestingly, CTPG not only enhanced the proliferation of splenocytes but also reduced the apoptosis of splenocytes induced by cisplatin. In H22 tumor mouse model, CTPG combined with cisplatin further inhibited the growth of H22 cells and reduced the side effects of cisplatin. Taken together, CTPG inhibited the growth of HCC through direct antitumor effect and indirect immunoenhancement effect, and improved the antitumor efficacy of cisplatin.

BackgroundPrevious studies have been demonstrated that Cistanche tubulosa phenylethanoid glycosides (CTPG) exhibit antitumor effects on a variety of tumor cells. However, the antitumor effects of CTPG on HepG2 and BEL-7404 hepatocellular carcinoma (HCC) cells are still elusive.ResultsOur study showed that CTPG significantly inhibited the growth of HepG2 and BEL-7404 cells through the induction of cell cycle arrest and apoptosis, which was associated with the activation of MAPK pathways characterized by the up-regulated phosphorylation of p38, JNK, and ERK1/2 and mitochondria-dependent pathway characterized by the reduction of mitochondrial membrane potential. The release of cytochrome c and the cleavage of caspase-3, -7, -9 and PARP were subsequently increased by CTPG treatment. Moreover, CTPG significantly suppressed the migration of HepG2 through reducing the levels of matrix metalloproteinase-2 and vascular endothelial growth factor. Interestingly, CTPG not only enhanced the proliferation of splenocytes but also reduced the apoptosis of splenocytes induced by cisplatin. In H22 tumor mouse model, CTPG combined with cisplatin further inhibited the growth of H22 cells and reduced the side effects of cisplatin.ConclusionTaken together, CTPG inhibited the growth of HCC through direct antitumor effect and indirect immunoenhancement effect, improved the antitumor efficacy of cisplatin.

Pleurotus feruleus is an edible and medicinal mushroom. We previously demonstrated that the crude and purified polysaccharides from cultivated P. feruleus (PFCP-C and PFPS-C) had the immunostimulatory activity. Here, the crude and purified polysaccharides of wild P. feruleus (PFCP-W and PFPS-W) were compared with PFCP-C and PFPS-C on the immunostimulatory activity. PFCP-W and PFCP-C showed similar activity on dendritic cell (DC) maturation in vitro, whereas the activity of PFCP-W was higher than that of PFCP-C in vivo. The monosaccharide compositions of PFPS-W and PFPS-C were different. PFPS-W was sulfated polysaccharides with crude surface. PFPS-W and PFPS-C promoted the activation of DCs and macrophages through TLR4 signaling pathway, whereas the activity of PFPS-W was higher than that of PFPS-C. The maturation and migration of DCs in vivo were significantly increased by PFPS-W and PFPS-C. Moreover, PFPS-W and PFPS-C significantly enhanced the antigen-specific cellular immune responses induced by DC-based vaccine.

With Fe(NO3)3·9H2O and Bi(NO3)3·5H2O as raw materials, different sillenite-type compounds and elemental bismuth were prepared by a facile one-pot solvothermal method using H2O, C2H5OH, (CH2OH)2 and C3H8O3 as solvents, respectively. The structure, morphology, elemental compositions and properties of samples were examined by XRD, SEM, TEM, ICP, XPS, N2 adsorption and desorption, UV-vis DRS and PL. The photocatalytic activities of different samples were evaluated by the photodegradation of RhB under visible-light irradiation (λ > 400 nm), and results show that Bi36Fe2O57 prepared using C2H5OH as the solvent owns the optimum performance. In order to explore the reaction mechanism, an additional experiment was designed to investigate the main active species during the photodegradation process via dissolving different trapping agents in the reaction solution before light irradiation. The results show that superoxide radical anions play a major role in this system since the RhB degradation was significantly suppressed after the addition of benzoquinone.

ZSM-5 (core)/SAPO-11 (shell) composite molecular sieve was synthesized by the hydrothermal method in order to combine the advantages of ZSM-5 and SAPO-11 for the methylation of naphthalene with methanol. For comparison, the mechanical mixture was prepared through the blending of ZSM-5 and SAPO-11. The characterization results indicated that ZSM-5/SAPO-11 composite molecular sieve exhibited a core–shell structure, with the ZSM-5 phase as the core and the SAPO-11 phase as the shell. The pore size of the composite was between that of ZSM-5 and SAPO-11. The composite had fewer acid sites than ZSM-5 and mechanical mixture while more acid sites than SAPO-11. The experimental results indicated that the composite exhibited high catalytic performances for the methylation of naphthalene with methanol.

The mercury release during pyrolysis of eight Chinese bituminous coals under N2 at temperatures up to 1200 °C was studied. The pyrolysis experiment was carried out in a quartz reactor. Results show that higher than 93% of mercury release out during pyrolysis. The release of mercury from all the coals begins at about 150 °C with two or three mercury peaks at the similar temperature range. The correlation analysis shows that mercury in the coals has close relation with the mineral and the mercury released at different peaks is mainly correlated with different types of material in the coals. The first peak located at 150–400 °C is mainly correlated with carbonate mineral as well as organic material in the coals. The second peak located at 500–600 °C is mainly correlated with sulfide minerals in the coals. The third peak located at higher than 750 °C is mainly correlated with aluminosilicate mineral in the coals. A large part of mercury in coal can be removed by pyrolysis below 400 °C.

Herein, a series of SAPO-11 molecular sieves were modified by citric acid and hydrochloric acid. They were characterized by ICP, XRD, SEM, N2 adsorption–desorption, NH3-TPD, 29Si MAS NMR, and Py-IR and evaluated by the methylation of naphthalene with methanol to 2,6-dimethylnaphthalene (2,6-DMN). According to the XRD results, hydrochloric acid at a high concentration not only removed extra-framework aluminum but also deleted framework silicon; this resulted in the formation of crystal defects. N2 adsorption–desorption results showed that all the samples possessed micropores and secondary mesopores. The SAPO-11 sample modified with 4 mol L−1 hydrochloric acid for 30 min exhibited the largest secondary mesopore size distributions. NH3-TPD and 29Si MAS NMR showed that hydrochloric acid at a high concentration could eliminate more acid sites. SAPO-11 modified with 4 mol L−1 hydrochloric acid for 30 min presented high catalytic performance for the methylation of naphthalene; this was mainly attributed to the amount of secondary mesopores in the SAPO-11 molecular sieves.

The mercury release from coal gangue and coal slime has attracted wide interest, because of the utilization of coal gangue and coal slime in some power plants. In order to develop the Hg control technology, it is necessary to gain the information on the Hg release during thermal treatment of coal gangue and coal slime. This paper presents a study about Hg release during thermal treatment of two coal gangues and coal slimes under air and N2 atmosphere through the online atomic fluorescence spectroscopy aided with the Ontario Hydro Method. The result shows that the release profiles of Hg for the two coal gangues and two coal slimes are similar under the same atmosphere, respectively. Most of the Hg is released at

Pleurotus ferulae is an edible mushroom and has been used in Uygur medicine for a long time. In this study, we purified polysaccharides from P. ferulae (PFPS) and investigated its structural characteristics. We obtained a homogeneous PFPS with a molecular weight of around 1600 kDa and prominent characteristic polysaccharide groups, which mainly contained glucose (97%), followed by mannose and galactose (3%). Both 1H and 13C NMR spectra indicated that PFPS contained both α- and β-anomeric configurations. Atomic force microscopy and Congo red-staining data further suggested that PFPS belonged to a linear branched structure that existed in flexible single chains at low concentrations and could form aggregates such as a triple-helical structure at high concentrations. Moreover, PFPS promoted the maturation of dendritic cells through a TLR4 mediated signaling pathway, which is characterized by the increased expressions of CD40, CD86, IL-12 and TNF-α and the decreased endocytosis. The results suggest that PFPS has immunoregulatory activities.

Release behaviors of arsenic (As) during pyrolysis of two Chinese coal gangues were studied in this report. The pyrolysis experiments were carried out in a temperature programmed tube furnace under N2 atmosphere with different temperature (200-1200 ºC), residence time (0-50 min), heating rate (10-50 ºC min-1) and N2 gas flow rate (100-500 cm3 min-1). The experiment results, under different pyrolysis conditions, indicate that the release ratio of As increases with increasing temperature, as well as residence time during pyrolysis of coal gangues. Besides that, higher heating rate during pyrolysis of coal gangues can stimulate the As release from coal gangue to some extent. The release ratio of As increases to a maximum and then decreases when the N2 gas flow rate is increased. The results imply that different modes of ocurrence of As exist in two coal gangues. The As release has positive relation with the volatile matter release. As is more easily released than coal gangue matrix during coal gangue pyrolysis.

Artemisia absinthium L. has pharmaceutical and medicinal effects such as antimicrobial, antiparasitic, hepatoprotective, and antioxidant activities. Here, we prepared A. absinthium ethanol extract (AAEE) and its subfractions including petroleum ether (AAEE-Pe) and ethyl acetate (AAEE-Ea) and investigated their antitumor effect on human hepatoma BEL-7404 cells and mouse hepatoma H22 cells. The cell viability of hepatoma cells was measured by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. The apoptosis, cell cycle, mitochondrial membrane potential (&Delta, &psi, m), and reactive oxygen species (ROS) were analyzed by flow cytometry. The levels of proteins in the cell cycle and apoptotic pathways were detected by Western blot. AAEE, AAEE-Pe, and AAEE-Ea exhibited potent cytotoxicity for both BEL-7404 cells and H22 cells through the induction of cell apoptosis and cell cycle arrest. Moreover, AAEE, AAEE-Pe, and AAEE-Ea significantly reduced &Delta, m, increased the release of cytochrome c, and promoted the cleavage of caspase-3, caspase-9, and poly(ADP-ribose) polymerase (PARP) in BEL-7404 and H22 cells. AAEE, AAEE-Pe, and AAEE-Ea significantly upregulated the levels of ROS and C/EBP-homologous protein (CHOP). Further, AAEE, AAEE-Pe, and AAEE-Ea significantly inhibited tumor growth in the H22 tumor mouse model and improved the survival of tumor mice without side effects. These results suggest that AAEE, AAEE-Pe, and AAEE-Ea inhibited the growth of hepatoma cells through induction of apoptosis, which might be mediated by the endoplasmic reticulum stress and mitochondrial-dependent pathway.

Although BiOBr exhibits unique layer structures and good visible light response features as photocatalysts, it has been limited by low surface area and poor carries separation. Herein, a simple hydrothermal approach is reported for planting 2D BiOBr nanosheets on 1D SiC whiskers to obtain the binary hybrid structure. By further controlling the hydrothermal temperature, the loading content of BiOBr on SiC whiskers surface, the band structure of BiOBr/SiCw hybrids could be finely tuned to optimize photodegradation activity. Results demonstrate that the construction of BiOBr/SiC hybrid structure not only increases surface area to provide more activity sites, but also improves photo-induced carriers transfer for strengthening the separation of the photo-induced carrier, which favors photodegradation activity. More importantly, the electron spin resonance and capture experiment reveals that holes are the main species responsible for the oxidation of contaminants. Benefited from the above characteristics, the optimized BS160 exhibits efficient photodegradation ability, where 97% Rhodamine B (RhB) is eliminated after 15 min and 60% tetracycline hydrochloride is degraded after 60 min under visible light irradiation, respectively. Moreover, the optimized BS160 also displays excellent photocatalytic stability after 5 reusability cycles. This work paves a new route for the development of photocatalysts based on BiOBr.

Effective thermal shielding materials with perfect anti-ablation and mechanical performances play a pivotal role of protecting aircraft suffering harsh conditions. With graphene oxide (GO) and nano-silicon spheres as raw material, a layered Si/GO precursor film was prepared by filtration, followed by in-situ carbothermal reaction to obtain the composite film of SiC and graphene (SiC/G film). The as-obtained material shows a sandwich-like anisotropic structure, with excellent anti-ablation performance in ablation experiment. The film exhibit a high mechanical stiffness with hardness and elastic modulus of 0.56 and 3.40 GPa, respectively. Besides, in- and out-plane thermal conductivity are 27.98 and 0.15–0.23 Wm−1 K−1, respectively. In the film, the orientated graphene sheets are not only the scaffold to retain the integrity of the film, but also improve in-plane thermal dissipation efficiency. Meanwhile, in-situ grown SiC particles act as the major anti-ablation functional layer, as well as the interlayer spacer to retard the heat transfer perpendicular to the film. Therefore, this novel sandwich-like structure composed by SiC and graphene layers could offer great protection from multiple ablation shocks in many fields. Keywords: Thermal shielding materials, Graphene, SiC, Composite film

A series of SAPO-11 zeolites with different Si contents were prepared by hydrothermally synthesized method. They were characterized by ICP, XRD, SEM, FT-IR, N2 adsorption-desorption, NH3-TPD and 29Si MAS NMR, and evaluated by the methylation of naphthalene with methanol to 2,6-dimethylnaphthalene (2,6-DMN). According to XRD and SEM results, the crystallinity of SAPO-11 sample increased with increase of the Si content until the SiO2/Al2O3 ratio was up to 0.2. However, a reduction in the crystallinity was observed with further increase of the Si content of the synthesis. N2 adsorption-desorption results showed that all the samples possessed micropores and secondary mesopores. SAPO-11 sample with SiO2/Al2O3 ratio of 0.2 exhibited the largest secondary mesopores size distributions. NH3-TPD and 29Si MAS NMR showed that the Si content was incorporated into the framework affecting not only the acid sites but also the acid strength of SAPO-11. SAPO-11 with SiO2/Al2O3 ratio of 0.2 presented the high catalytic performances for the methylation of naphthalene, which was mainly attributed to the amount of secondary mesopores in the SAPO-11 zeolite.

A free-standing paper-like three-dimensional graphene framework (3DGF) with orientated laminar structure and interconnected macropores, was obtained by the hard template-directed ordered assembly. As the sacrificial templates, polystyrene (PS) latex spheres were assembled with graphene oxide (GO) to build up a sandwich type composite film, followed by heat removal of which with a simultaneous reduction of GO. The 3DGF exhibited high specific surface area of 402.5 m2/g, controllable pores and mechanical flexibility, which was employed as the binder-free supercapacitor electrode and shows high specific gravimetric capacitance of 95 F/g at 0.5 A/g, with enhanced rate capability in 3 electrode KOH system.

High-performance electromagnetic shielding materials are highly desired due to the radiation and interference problems of electronic equipment. In this work, a flexible graphene/multi-walled carbon nanotubes (MWCNTs)/Polydimethylsiloxane (PDMS) electromagnetic shielding composite is fabricated with 3D graphene/MWCNTs foam as electrical conductive skeleton. The structure and composition evolution of foams are studied during the carbonization process from 1200 to 1600 °C and the graphitization of ultra-high temperature (2800 °C). With the removal of functional groups, the repair of defects enhances the ohmic loss while the polarization loss is reduced. An optimal electromagnetic interference shielding effectiveness (EMI SE)is found with an EMI SE of 54.43 dB at 1400 °C. Moreover, compared to pure PDMS, the thermal conductivity of the composites is increased by 193% and the compressive strength is improved from 1.40 MPa to 1.94 MPa. This contribution provides a guidance for designing high-performance carbon-based electromagnetic shielding materials.

BackgroundThe enhancement of immunity is very important for immunocompromised patients such as cancer patients with radiotherapy or chemotherapy.Glycyrrhiza uralensishas been used as food and medicine for a long history.G. uralensispolysaccharides (GUPS) were prepared and its immunostimulatory effects were investigated.MethodsHuman monocyte-derived dendritic cells (DCs) and murine bone marrow-derived DCs were treated with different concentrations of GUPS. The DCs maturation and cytokine production were analyzed by flow cytometry and ELISA, respectively. Inhibitors and Western blot were used to study the mechanism of GUPS. The immunostimulatory effects of GUPS were further evaluated by naïve mouse model and immunosuppressive mouse model induced by cyclophosphamide.ResultsGUPS significantly promoted the maturation and cytokine secretion of human monocyte-derived DCs and murine bone marrow-derived DCs through TLR4 and down-stream p38, JNK and NF-κB signaling pathways. Interestingly, the migration of GUPS treated-DCs to lymph node was increased. In the mouse model, GUPS increased IL-12 production in sera but not for TNF-α. Moreover, GUPS ameliorated the side effect of cyclophosphamide and improved the immunity of immunosuppressive mice induced by cyclophosphamide. These results suggested that GUPS might be used for cancer therapy to ameliorate the side effect of chemotherapy and enhance the immunity.

ZSM-5 (core)/SAPO-11 (shell) composite molecular sieve was synthesized by the hydrothermal method in order to combine the advantages of ZSM-5 and SAPO-11 materials for the methylation of naphthalene with methanol. For comparison, the catalytic performance of mechanical mixture of ZSM-5 and SAPO-11 was also evaluated. The characterization results proved that ZSM-5/SAPO-11 composite has a core-shell structure. The pore size of the composite was between that of ZSM-5 and SAPO-11. The composite had fewer acid sites than ZSM-5 and mechanical mixture, but more acid sites than SAPO-11. The experimental results indicated that the composite exhibited good catalytic performance in the methylation of naphthalene with methanol.

The utilization of coal gangue in a power plant has attracted wide interest in China; however, coal gangue represents a new anthropogenic source of mercury pollution due to its high mercury content. Understanding the modes of occurrence of mercury in coal gangue is crucial for developing the mercury control technology used during coal gangue combustion. In this study, the mercury in four typical coal gangues in China was characterized by a sequential extraction procedure (SEP) coupled with a temperature-programmed decomposition (TPD) method. The method is proved to be an effective approach in studying the modes of occurrence of mercury as well as the thermal stability of coal gangues by distinguishing the characteristic release temperature during the thermal decomposition process. The iron–manganese oxide-bound Hg releases at a temperature range of 200–600 °C, while the carbonate-bound Hg releases at a temperature range of 250–300 °C. The organic-bound Hg, sulfide-bound Hg, and silicate-bound Hg release a...

MCM-41 was calcined at 500, 560, 600 or 650 °C. It was used as support for NiW catalysts of hydrodenitrogenation (HDN) for quinoline in order to investigate the influences of the MCM-41’s calcination temperature on the structure and the HDN performance of NiW catalysts. The NiW catalysts were characterized by XRD, N2 adsorptiondesorption, XPS, Raman, HRTEM and Py-IR techniques. The results showed that the surface area (S BET ), the average pore diameter (Dp) and the pore volume (Vp) of the MCM-41 increased with increase of the MCM-41’s calcination temperature. The high S BET , Dp and Vp were beneficial for the high dispersion of W species, the formation of appropriate nature of W species and acid sites on the catalysts. The HDN activity followed the order of NiW-650≈NiW-600>NiW-560>NiW-500, while the relative selectivity of HDN pathways was similar for all the catalysts.

MCM-41 materials modified by Al, Zr and Ti were used as supports for the preparation of the NiW hydrodenitrogenation (HDN) catalysts. The modified supports, with highly dispersed Al, Zr and Ti species and without loss of the MCM-41 characteristics, can be prepared by a postsynthetic method. The incorporation of Al, Zr and Ti can enhance the density of acid sites on the modified MCM-41, so as to increase the density of acid sites and even enhance the dispersion of Ni, W species on the corresponding catalysts. The HDN results showed that the incorporation of Al, Zr and Ti can increase the HDN activity of the catalysts and the activity followed the order of Ni/W/Al > Ni/W/Zr > Ni/W/Ti > Ni/W. The high HDN activity of Ni/W/Al ascribed to the high density of acid sites and the well dispersion of the Ni and W species on the catalyst.

The dynamic release behavior of elemental Hg (Hg0) during thermal treatment of two bituminous coals was studied under N2, CO2 and air atmospheres. The results show that the profiles of Hg0 released present several peaks during thermal treatment of two bituminous coals. The Hg peak profiles for the same coal are different with the different atmosphere used. The amount of Hg0 released from the coals is about 92-94, 73-74 and 31-33% under N2, CO2 and air atmosphere, respectively. This indicates that the Hg0 is the dominant form during thermal treatment of the coals under N2 atmosphere whereas part of Hg0 is converted into the oxidized Hg during thermal treatment of the coals under CO2 and air atmosphere. The total Hg released is promoted by the volatile matter release to some extent while the Hg0 released is mainly affected by the atmospheres used.

Novel highly active visible light photocatalysts BiOBr–TiO2 nanocomposites were prepared by a facile one-pot solvothermal approach. Series of characterizations verified that the BiOBr nanoscale crystals are highly dispersed in amorphous TiO2 to form the hybrid mesoporous structure. The material shows excellent photocatalytic performance towards photodegradation of Rhodamine B under visible light irradiation. The content ratio between TiO2 and BiOBr plays a key role in the microstructure of the nanocomposites, so as to result in distinguished photocatalytic activity. The sample with a molar ratio of 10 between TiO2 and BiOBr shows the optimum performance. The high photocatalytic activity of BiOBr–TiO2 nanocomposites under visible light could be ascribed to the large surface area, opened mesoporous structure, appropriate band-gap, as well as synergistic effect between TiO2 and BiOBr. Besides, the BiOBr–TiO2 composites render a facile separation due to the three-dimensional superstructure. The BiOBr–TiO2 photocatalyst is very promising for water purification as well as other environmental applications.

As a unique 2D carbon crystal with a zero bandgap nature, superior electron mobility and high transparency, graphene was introduced into BiOBr–TiO2 (BT) composites as a nano-filler by a facile one-pot approach to obtain a novel BiOBr–TiO2–graphene (BTG) ternary photocatalyst. The material exhibits superior photocatalytic activity towards the photodegradation of Rhodamine B under visible light irradiation, and has an enhancement in photocatalytic rate of up to 2.83-fold higher than that of the BT catalyst at an optimum content of 0.75 wt% graphene in the composites. The homogeneous hybrid colloids of BiNO3, tetrabutyl titanate and graphene oxide were employed as the precursor, while GO was reduced into graphene with a simultaneous formation of tetragonal BiOBr and amorphous TiO2 in the solvothermal process. The highly dispersed 2D graphene in the composites will not only serve as the electron reservoir, but also act as a conductive network to improve the migration efficiency of electrons. Furthermore, the spacer effect of graphene will increase the surface BiOBr concentration and decrease the crystal size of BiOBr, as well as facilitate the formation of relatively uniform channel-like pores, which is beneficial for the photocatalytic performance. The photodegradation in the BiOBr–TiO2–graphene system was carried out dominantly by an indirect dye photosensitization process and the superoxide radical anions ˙O2− were considered as the main reactive species. This work provides an in-depth perspective for understanding the graphene-involved photocatalytic mechanism and stimulates the design of novel catalytic materials for the exploitation and utilization of solar energy.