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Hydrothermal organic reactions in the presence of mineral catalysts have been well established by laboratory experiments. However, little is documented about hydrothermal catalytic conversion (HTCC) and the metastable existence of complex molecules in continental hydrothermal systems. Five freshly mined ores containing oil and solid bitumen and associated unmineralised host sediment were sampled from the Beichang mine, Jinding Zn/Pb ore deposit, Lanping, near the Indo-Eurasian collisional margin, southeastern Tibetan Plateau. Here we show evidence for a wide range of mineral (ZnS/PbS) catalysis of polycyclic aromatic compounds in the natural subsurface. An interpretation of hydrothermal alteration (non-biodegradation) was made for the unresolved complex mixture. From unmineralised host sediment through oils to the solid bitumen, a stepwise interaction of organic compounds with metal-bearing hydrothermal fluids was demonstrated by the transformation of polycyclic aromatic hydrocarbons (PAHs) and phenyl/sulfur/oxygen-containing compounds that are thought to be generated through HTCC. Thermodynamically-unstable phenyl derivatives (ortho- or α-substituted) resulted from hydrothermal alteration (ring opening) of the middle and naphthenic (low energy) rings of peri-condensed parent PAHs, as supported by the dominance of 1-phenyldibenzothiophene, 1-phenyldibenzofuran, triphenyleno[1,12-bcd]thiophene, triphenyleno[1,12-bcd]furan, 9-phenylphenanthrene, 1,1′:2′,1′′:2′′,1′′′-quaterphenyl, and the corresponding thiophenes or furans over other isomers. Heteroatom addition to phenyl-derivatives generates abundant heterocyclic compounds, which can undergo further dehydrocyclisation. In the presence of ZnS/PbS, the abundance of three compound classes (unsubstituted PAHs, ‘aryl-aryl’ linked phenyl-derivatives, and S/O atom-containing compounds) is mainly hydrothermally controlled, rather than thermodynamically controlled. Various phenyl/sulfur/oxygen-containing compounds are the metastable equilibrium products of a series of complex redox reactions under specific hydrothermal conditions. We hypothesise that the ubiquitous triphenyleno[1,12-bcd]furan is an important marker for hydrothermal organic–inorganic interactions in the Zn/Pb deposit. The relative abundance of 9-phenylphenanthrene provides a measure of the degree of hydrothermal alteration and HTCC. Our data is consistent with a close interaction of ascending metalliferous hydrothermal fluids with indigenous organic matter/compounds. Hydrothermal fluids, in the presence of sphalerite (and/or galena), are highly effective for activation of the carbon–carbon bonds in PAHs.

The generation mechanism of abiogenic alkane gas and whether the gas has industrial values are the focus of international attention. CH4 generated by Fischer–Tropsch synthesis is an important constitutent of abiogenic alkane gas. The study on the components, isotopic compositions, and crust-mantle mixing model indicates that, the alkane gas from the Qingshen gas field in the Songliao Basin is contributed by abiogenic alkane gas from Fischer–Tropsch synthesis, besides the mantle-derived abiogenic alkane gas. The authors have selected the endmembers of typical biogenic and abiogenic gases and conducted mixed source calculation. The abiogenic alkane gas accounts for over 60 × 109 m3 in the proven reserves of the gas field, in which the amount of CH4 generated by Fischer–Tropsch synthesis exceeds 9.6 × 109 m3. The calculation results indicate that, abiogenic alkane gas under organic–inorganic interactions can form commercial accumulations. Since typical biogenic gas is predominant in conventional gas pools, and high- to over-mature coal-derived gas displays a certain similarity with abiogenic alkane gas, the typical characteristics of abiogenic gas is concealed. Therefore, abiogenic alkane gas generated by organic–inorganic interactions may exist widely in petroliferous basins, and its contribution to gas pools may be underestimated previously.

TaD11-2A affects grain size and root length and its natural variations are associated with significant differences in yield-related traits in wheat. Brassinosteroids (BRs) control many important agronomic traits and therefore the manipulation of BR components could improve crop productivity and performance. However, the potential effects of BR-related genes on yield-related traits and stress tolerance in wheat (Triticum aestivum L.) remain poorly understood. Here, we identified TaD11 genes in wheat (rice D11 orthologs) that encoded enzymes involved in BR biosynthesis. TaD11 genes were highly expressed in roots (Zadoks scale: Z11) and grains (Z75), while expression was significantly suppressed by exogenous BR (24-epiBL). Ectopic expression of TaD11-2A rescued the abnormal panicle structure and plant height (PH) of the clustered primary branch 1 (cpb1) mutant, and also increased endogenous BR levels, resulting in improved grain yields and grain quality in rice. The tad11-2a-1 mutant displayed dwarfism, smaller grains, sensitivity to 24-epiBL, and reduced endogenous BR contents. Natural variations in TaD11-2A were associated with significant differences in yield-related traits, including PH, grain width, 1000-grain weight, and grain yield per plant, and its favorable haplotype, TaD11-2A-HapI was subjected to positive selection during wheat breeding. Additionally, TaD11-2A influenced root length and salt tolerance in rice and wheat at seedling stages. These results indicated the important role of BR TaD11 biosynthetic genes in controlling grain size and root length, and also highlighted their potential in the molecular biological analysis of wheat.

The stability analysis of damaged landslides and unstable debris is important for rescue work and emergency operations. This paper investigates a predisposed geological emergence, inducing the factors and deformation processes of the Zhongbao landslide, which happened on July 25, 2020. The stability of the landslide debris was evaluated by an integrated monitoring system consisting of ground-based radar, unmanned aerial vehicles, airborne Lidar, thermal infrared temperature monitoring, GNSS displacement monitoring, deep displacement monitoring, and rainfall monitoring. The strata and weak layer controlled the landslide failure, and topography defined the boundary of the failed rock mass. A continually intensive rainfall caused the deformation and accelerated failure of the landslide. The shallow and steep deposit (Part I) firstly slid at a high velocity, and then pushed the rear part of the landslide (Part II) to deform, forming numerous cracks, which accelerated the rainfall infiltrating into the rock mass. The moisture content increase could decrease the strength of the shale rock within the bedding planes. Finally, with the rock and soil mass sliding along the weak layer, a barrier dam and a barrier lake were formed. The monitoring and numerical simulation results showed that after the landslide failure, there was still local collapse and deformation occurrences which threatened rescue work and barrier lake excavation, and the stability of the accumulation area gradually decreased as the rainfall increased. Therefore, the barrier dam was not excavated until the accumulation rate gradually stabilized on July 28. Moreover, most of the reactivated deposits still accumulated in the transportation and source areas. Thus, in August, the displacement of the landslide debris gradually accelerated in a stepwise manner, and responded strongly to rainfall, especially in the accumulation area, so that it was inferred that the damaged landslide could slide again and cause a more threatening and severe failure. The analysis results of the study area can provide references for the failure mechanism of a rainfall-induced landslide and the stability evaluation of a damaged landslide.

Li-rich disordered rock-salt cathode (DRX) materials with advantage of low cost, long cycle life, nature abundant resource and high power and energy density attracted a great deal of scholarly attention. However, the poor cycle stability and the unclear realization of cation and anion redox activity in low-cost element system have severely hindered the construction of high-performance DRX. Herein, a promising class of Ti-Mn based cathode materials Li1.25Mn0.25Nb0.25Ti0.25O2 and Li1.25Mn0.25Ti0.5O1.75F0.25 were designed and successfully synthesized to construct high energy density DRX and investigate the effect of fluorination on cation and anion redox activity. The results show that both fluoridized and unfluoridized DRX possess a similar structure (Fm-3 m), but distinctly different charge/discharge profiles. The fluoridized cathode shows high initial charge/discharge capacity of 317.3/283.9 mAh g−1, specific energy density of 1370.4/735.5 Wh kg−1 and stable capacity retention with a discharge capacity of 202.6 mAh g−1 after 20 cycles at 20 mA g−1. Combining relevant spectroscopic results and HRTEM images, we revealed that the excellent cyclability of Li1.25Mn0.25Ti0.5O1.75F0.25 is rooted in the weakened adverse effects of moderated oxygen redox and the reduced Jahn–Teller distortion effect resulting from Mn3+, endowing the fluoridized DRX with better structural stability and larger Mn2+/Mn4+ reservoir. The strategy of constructing low cost oxyfluoride and the understanding of the mechanism of fluorination induced cation and anion redox activity would provide reference for the development of high-performance DRX materials.

The sources and origins of polycyclic aromatic hydrocarbons (PAHs) in thirty eight Paleogene organic-rich shales and mudstones from the Shahejie Formation in the Dongying Depression, Bohai Bay Basin have been assessed. Phenanthrene, retene, cadalene, fluoranthene, pyrene, benz[a]anthracene, triphenylene, chrysene, benzofluoranthenes, benzo[e]pyrene, benzo[a]pyrene, indeno[1,2,3-cd]pyrene, benzo[ghi]perylene and coronene were identified in the sediments. The symmetrical 4-ring triphenylene was unequivocally identified by comparison with mass spectra and a synthetic standard. Key PAH ratios including fluoranthene/(fluoranthene + pyrene), benzo[a]anthracene/(benz[a]anthracene + chrysene), indeno[1,2,3-cd]pyrene/(indeno[1,2,3-cd]pyrene + benzo[ghi]perylene) and benzofluoranthene/(benzofluoranthene + benzo[e]pyrene) indicate a mainly diagenetic/catagenetic origin for the PAHs. The relative low abundance of the 6-ring indeno[1,2,3-cd]pyrene and benzo[ghi]perylene and the 7-ring coronene suggest the absence of larger, high temperature wildfires, either due to inadequate seasonality of the humid-arid climate, or limited terrigenous organic matter input. Phenanthrene and alkylphenanthrenes are likely derived from phytoplankton, based on the correlation of the relative abundance of C27 regular steranes and 1-methylphenanthrene and 9-methylphenanthrene. The methylphenanthrenes, triphenylene, alkyltriphenylenes and benzo[e]pyrene may share a common source as their occurrences are closely correlated. Four groups of samples were differentiated on the basis of the relative abundance and distribution patterns of benz[a]anthracene, triphenylene and chrysene, showing that these compounds are useful PAH markers in petroleum geochemistry. Thermal maturation effects are the major control on the relative abundance and distribution of the non-combustion derived PAHs (e.g. biphenyl, fluorene, fluoranthene, pyrene, benz[a]anthracene, triphenylene) in lacustrine sediments. Benz[a]anthracene decreases in relative abundance while triphenylene increases in relative abundance with burial depth. Correlation of the newly defined triphenylene-chrysene ratio (TCR; triphenylene/(triphenylene + chrysene) with burial depth and biomarker maturity parameters was observed, suggesting that it may be a useful maturity indicator for lacustrine oils and sediments in the Dongying Depression.

Lacustrine organic-rich source rocks (shales and mudstones) were examined to assess the depositional environment and organic input sources of the third and fourth members of the Eocene Shahejie Formation, Bohai Bay Basin, China. Major organic contributions to the Shahejie Formation from dinoflagellates, diatoms, Botryococcus and marine pelagophyte/chrysophyte algae were determined using n-alkane distributions, gammacerane index and diagnostic steranes. Traces of higher plant biomarkers suggest that terrigenous organic inputs were limited. The pervasive presence of β-carotane, aryl isoprenoids, paleorenieratane, renieratane, isorenieratane, 2α-methylhopanes and crocetane indicate significant organic contributions from bacterial communities including cyanobacteria, purple sulfur bacteria (Chromatiaceae), green sulfur bacteria (Chlorobiaceae), and sulfate-reducing bacteria. The extent of H2S content, bacterial sulfate reduction, and photic zone euxinia (PZE) were evaluated by determining the aryl isoprenoids ratio (AIR: 0.7–9.0), the presence of isorenieratene derivatives, and the fate of sulfur in the water column. There was a decrease of PZE extent and duration from the northeast to the southwest of the palaeo-lake, and there was a decrease of water body salinity and bottom water anoxia from the fourth to the third member of the Shahejie Formation. Abrupt environmental perturbations in the third member of the Shahejie Formation are indicated not only by significant changes in parameters such as the pristane/phytane and β-carotane/n-C20 alkane ratios, the gammacerane index, the isorenieratane/C18 aryl isoprenoid, and the AIR, but also by the time lag in the expansion of cyanobacterial lineages after the expansion of purple/green sulfur bacteria, as well as seawater incursions. The unexpected occurrence of intact C30 4-desmethylsteranes (24-n-propylcholestanes) in the Shahejie Formation is first reported here, after very careful checking, and provides unambiguous biological evidence for at least two marine transgression events reaching the Eocene Dongying palaeo-lake. The organic enrichment of the petroleum source rocks in the Shahejie Formation is a consequence of combined indigenous lacustrine algal production, the constrained and favourable preservation conditions, and significant bacterial contributions and marine organic matter inputs to the lake.

This study was aimed to investigate the impact of probiotics on regulating the ROS/JNK signaling pathway their underlying mechanism of action in the treatment of nonalcoholic fatty liver disease. For this purpose, male C57BL/6 mice were randomly divided into three groups: control, probiotics, and model groups. Methionine and choline deficiency (MCD) diets were fed for four weeks to establish a NAFLD mouse model. Serum levels of ALT, AST, TC, and TG were detected. Moreover, the pathological changes of the liver and ileum tissues were observed by hematoxylin and eosin (H&E) staining, and the content of reactive oxygen species (ROS) in liver tissues was determined. In addition, the levels of D-lactic acid and plasma and small intestine diamine oxidase were measured to evaluate the effects of probiotics on the intestinal tract of NAFLD mice. The expression levels of p-JNK, Bax, and Caspase-3 were established to analyze the regulatory mechanism of probiotics on the JNK signaling pathway. We found that probiotics improve liver function, repair intestinal barrier and significantly suppressed oxidative stress, JNK phosphorylation. Moreover, the application of probiotics regulated the expression of signaling pathway-related proteins and promoted the intestinal barrier function repair and decreased intestinal permeability. The data above suggest that probiotics alleviate NAFLD, whose mechanism might be associated with the regulation of ROS/JNK signaling pathway and the suppression of oxidative stress and apoptosis.

Background Inflammation induced by Helicobacter pylori (H. pylori) infection is the basis for the pathogenesis of H. pylori. Butyric acid, a diet-related microbial-associated metabolite, is connected to inflammation, metabolic syndrome, and other diseases. Several studies have indicated the effects of sodium butyrate (SB) against bacteria; however, the effects of SB on the main virulence factors of H. pylori, H. pylori-induced inflammation, and gut microbiota composition remain unclear. Materials and methods SB was supplemented in H. pylori coculture and administered to mice infected with H. pylori. The effects of SB intake on inflammation, gut microbiota composition, and short-chain fatty acids (SCFAs) in H. pylori-infected mice were assessed. Results The in vitro experiments demonstrated that SB not only inhibited the growth of H. pylori but also decreased the mRNA expression of CagA and VacA. SB intake reduced the production of virulence factors in H. pylori-infected mice, inhibited the IκBα/NF-κB pathway by reducing the expression of Toll-like receptors (TLRs), and reduced the production of TNF-α and IL-8. Further analysis demonstrated that H. pylori infection altered the relative abundance of the intestinal microbial community in mice. The level of SCFAs in the feces of H. pylori-infected mice was changed, although the intake of SB did not obviously change the level of SCFAs. Conclusions Our study showed that SB may decrease H. pylori-induced inflammation by inhibiting the viability and virulence of H. pylori and may reduce inflammation in association with the gut microbiota in H. pylori-infected mice. This study may provide novel insights into the mechanisms by which SB, a diet-related microbial-associated metabolite, affects H. pylori-induced disease development.

A self-nanocrystallization layer was prepared on the surface of a Ti alloy sample via shot peening to investigate its influence on the follow-up diffusion bonding between a titanium alloy and a TiAl-based alloy. The experiment results show that surface self-nanocrystallization treatment can accelerate the interface reaction between a Ti alloy and a TiAl alloy, lowering the bonding temperature of the sound joints by more than 50 K. Moreover, the thickness of the interface reaction layer plays an important role in the interfacial bonding strength. In this work, the maximum shear strength of the joint appears to have a thickness of about 1.8 μm. As a consequence, it is found that surface self-nanocrystallization treatment is helpful for optimizing the diffusion bonding process.

The main objective of this paper is to propose a product approximation for the Gamma function in the form of continued fraction, via the Tri-gamma function. The importance of this new formula is that the convergence of the corresponding asymptotic series is faster than other recently discovered asymptotic series, and some new inequalities related to the new formula are also established.

The Northeastern Laizhouwan Sag (NLS) is a marginal sag in the Bohai Bay Basin, China. Paleogene source rocks from 3 wells (K-a, K-b and K-c) in this region, i.e., the third to the first member of the Shahejie Formation (Es3, Es2, and Es1), and the third member of the Dongying Formation (Ed3) were investigated for their petroleum potentials and depositional environments using geochemical and palynological methods. Among these members, the Es3 and Es1 members hold considerable hydrocarbon potential, while the rest are relatively fair. Although there are variations between the wells, the organic matter (OM) in the Es3 member is primarily composed of low mature or mature type I-II1 kerogen, which were primarily contributed by lower aquatic organisms and prokaryotes. During the Es3 stage, saline, stratified, and anoxic bottom water prevailed in the K-a well, while freshwater and weak reducing conditions dominated the K-b well. The OM in the Es1 member was contributed more by lower aquatic organisms than that in the Es2 member, but both are primarily composed of types II1-II2 kerogen; further, OM in the Es2 member is low mature, while that for the Es1 member ranges from immature to low mature, and higher maturity is expected in deeper buried places for the two members. Saline and anoxic bottom water prevailed during the both Es2 and Es1 members. Compared with other members, noticeable terrigenous OM was deposited during the Ed3 stage, which is dominated by immature type II2 kerogen. Lower salinity and weak reducing depositional conditions occurred in the Ed3 member. OM enrichment in the Es3 member was mainly determined by primary productivity, while that of the K-a well was also enhanced by the anoxic bottom water condition. The accumulations of OM in other members are speculated to have been controlled by the deposition rate.

Silica supported gold nanoparticles were synthesized and promoted by lanthanum oxide as dopant. The influences of La2O3 and silica textural structure on the gold dispersion, formation of active species, crystalline composition and the reacting role of dopants were studied in detail. The characterization results suggested that the dispersion of gold nanoparticles depended on the textural structure of silica without lanthanum oxide doping where small mesopores are more preferable to disperse gold nanoparticles. The addition of lanthanum oxide largely increased the dispersion of gold nanoparticles and oxygen active sites independent of the textural structure of silica support. The interaction between lanthanum oxide and silica enhanced by the synergy facilitated the release of oxygen vacancies and transition of active oxygen species. In addition, the chemical properties were greatly changed after lanthanum oxide addition which was only inconspicuously impacted by the initial textural structure of silica supports, shedding light on the further design of economic gold catalyst based on simple synthesis method.

In order to better understand the relative contributions of various source rocks for petroleum in the Xihu Depression, East China Sea Basin, gas chromatography-mass spectrometry analyses of the saturated and aromatic fractions and carbon isotopic analyses of the purified n-alkanes and isoprenoids were performed. The molecular composition and individual n-alkane and isoprenoid carbon isotope compositions were determined for oils and extracts of Paleogene mudstones (TOC: 0.45–2.3%), carbonaceous mudstones (12.7–19.6%), and coals (48–60%) in the Xihu Depression, so as to discriminate the hydrocarbon sources of coals and associated mudstones to the petroleum generated in the basin. Abundant diterpanes (e.g., isopimarane, phyllocladane) are present in all the samples. The differences in the δ13C values of pristane and phytane indicate separate origins for the isoprenoids. A general negative sloping profile with increasing n-alkane carbon chain length was observed in coals, mudstones and oils from the Huangyan oilfield, with individual n-alkane δ13C values between −25.6‰ and −34.4‰. These values are characteristic of the isotopic compositions of C3 plants, and are also typical of fluvial/lacustrine depositional settings. The isotope compositions of individual n-alkanes from the extracts of coals and mudstones correlate with the relative concentration of terrigenous higher plant-derived diterpenoids, which suggests that plant phyla/classes (for example gymnosperm-derived diterpanes versus angiosperm-derived diterpanes) may be a control on the carbon isotope profiles of n-alkanes. For samples dominated by terrigenous organic matter, long chain n-alkanes with a large proportion of gymnosperm input are approximately 2–3‰ enriched in 13C relative to those with angiosperm input, regardless of lithology. The connections between the oils, coals, and mudstones allow determination of the patterns and variations for different hydrocarbon contributions, and provide a way of differentiating specific source contributions to petroleum in the Xihu Depression. Oils generated from the coals have heavier δ13C values with increasing chain length within a narrow range (approx. 2–3‰) and have more heterotrophic origins, whereas oils from the mudstones are more depleted in 13C with increasing carbon number (n-C20-31) and have a greater derivation from land plants. The 825B oils in the Huangyan oilfield have a greater angiosperm-sourced hydrocarbon contribution than those of the 825AD oils, which have a greater gymnosperm-sourced hydrocarbon contribution. The tricyclic and tetracyclic diterpanes and the isotopic compositions of individual n-alkanes and isoprenoids may be useful in differentiating contributions of coals and associated mudstones to petroleum.

Micro-variations of lipid hydrocarbons and biomarkers in well-laminated shales have not been extensively documented, especially within different rock textures, fabrics and mineralogies. Comparison of a pyrite cemented zone and its surrounding sediment may offer a new perspective on mineral control on preservation of hydrocarbons and organic carbon. A black well-laminated shale comprising two adjacent and contrasting calcareous (light) and pyrite (dark) laminae at the millimetre scale was selected from the Eocene Shahejie Formation, Dongying Depression, Bohai Bay Basin. It was horizontally sliced to separate a pyrite cemented concretion from the unaltered laminated shale, and investigated using geochemical techniques to assess the heterogeneity of elements, minerals, microfossils and hydrocarbons within the two slices. Micro-scale changes in source inputs were noted. For instance, the 4α-methylsteranes, dinosteranes and the triaromatic dinosteranes show varying distributions between the two slices, attributed to slight differences in dinoflagellate contributions. Similarly, variation in the amount of bacterial sulfate reduction is indicated by variations in the aryl isoprenoid ratio, relative amount of isorenieratane, long-chain n-alkane carbon isotopic composition and other molecular indicators including the relative amounts of dibenzothiophene, dibenzofuran, methyldibenzothiophene and methyltrimethyltridecylchromans. The primary control on these variations appears to be different euxinic water conditions, but diagenesis has also influenced the distributions. Differential anaerobic bacterial reworking of organic matter and pyrite concretion protection are responsible for organic geochemical variations on a millimetre-scale in the shale. The pyrite concretion has an altered record of its thermal history, but has a more accurate record of the organic geochemistry of microfossils and water column conditions. This study shows the potential for future investigations of closely-spaced vertical variation in organic geochemical parameters that may shed light on rapid temporal variation in organic matter input and depositional environment.

With the advent of the era of &ldquo, New Retail&rdquo, many manufacturers and retailers have begun to provide cross-channel return services to increase competitiveness. Our study takes return policy into a green dual-channel supply chain, wherein a manufacturer creates and sells green products simultaneously. We investigate the pricing and greening strategies for the supply chain players in the cases of providing and not providing cross-channel return service by employing the Stackelberg model under the hypothesis of a consistent pricing strategy. By comparing the equilibrium results of two cases, we find that the retailer will cooperate with the manufacturer to employ the cross-channel return policy when the spillover effect is greater than a threshold. Additionally, the green level of products is higher than before. The threshold decreases with consumers&rsquo, sensitivity to green products, which implies that the manufacturer is motivated to conduct marketing programs to enhance consumers&rsquo, willingness to buy green products. Moreover, we propose a contract to coordinate the supply chain. Finally, we discuss the scenarios if the supply chain implements a differential pricing strategy. Interestingly, the green level and the profits of the whole supply chain are greater than that under a consistent pricing strategy. However, the profits of the retailer are lower than profits in the other scenario, which is not beneficial to creating a stable green supply chain.

The CoOx-doped silica and its supported gold nanoparticles were synthesized by conventional thermal treatment or plasma treatment. The activity for CO oxidation displayed 100% CO conversion at only 338 K over the O2 plasma-treated Au/CoOx/SiO2-PO catalyst. Analysis of the results suggested that, different from the traditional calcined gold catalyst, the metal particles in the plasma-treated samples tended to be smaller and more homogeneous and highly dispersed on the surface of the support. The microstructure with a large surface contact and mesoporosity was more appropriate for the reactions. In addition, the O2 atmosphere plasma-treated samples generated a large amount of oxygen-supply centers, which in turn facilitated the low-temperature CO oxidation reaction. The plasma technique under an oxygen atmosphere is proved as an efficient treatment technique for gold catalysts.

In this paper, we establish some lower and upper bounds with explicit expressions for the Mills' ratio of the skew-generalized normal distribution. And for demonstrating the efficiency of our estimates, some numerical computations are provided.

A series of novel biomorphic CuO–ZrO 2 catalysts were prepared using a cotton bio-template and compared with conventional CuO–ZrO 2 catalysts. The physical and chemical properties of the as-obtained catalysts were characterized by techniques including X-ray diffraction (XRD), scanning electron microscope (SEM), transmission electron microscope (TEM), H 2 -temperature programmed reduction (H 2 -TPR), and O 2 -temperature programmed desorption (O 2 -TPD). The catalytic combustion of methane was chosen as the probe reaction. The results suggested that the bio-template method prepared porous biomorphic CuO–ZrO 2 catalysts consist of hollow microtubes. Comparing with conventional CuO–ZrO 2 catalysts, biomorphic CuO–ZrO 2 catalysts displayed better reducibility and oxygen mobility, stronger metal-oxides synergistic effect, appropriate particle size distribution, and lower activation energy. The crystalline state of zirconia transformed from a single crystallite phase of t-ZrO 2 into a complex of m-ZrO 2 and t-ZrO 2 after introducing the bio-template. With proper CuO content (20 mol%), the biomorphic CuO–ZrO 2 catalyst displayed preponderant properties. The compensation of surface lattice oxygen from bulk lattice oxygen was more available at high reaction temperatures.

A new type of Ni/MgO catalyst was prepared using atmospheric high-frequency discharge cold plasma. The influences of conventional method, plasma method, and plasma plus calcination method on the catalytic activity were studied and the CO 2 reforming of methane was chosen as the probe reaction. The catalysts were characterized by X-ray diffraction (XRD), transmission electron microscope (TEM), X-ray photoelectron spectroscopy, and CO 2 temperature-programmed surface reaction techniques. The results suggested that the nickel-based catalyst prepared by plasma plus calcination method possessed a smaller particle size and a higher dispersion of active component, better low-temperature activity and enhanced anti-coking ability. The conversion of CO 2 and CH 4 was 90.70% and 89.37%, respectively, and the reaction lasted for 36 h without obvious deactivation under 101.325 kPa and 750 °C with CO 2 /CH 4 = 1/1.

The meso silica supported novel nano-size gold catalysts promoted by MgO have been synthesized using deposition-precipitation technique for the total oxidation of carbon monoxide. The effects of MgO promoter and preparation procedure on the structure and performance of gold catalysts have been investigated. Better gold dispersion, smaller average size of Au particles and more oxygen mobility were observed in the Au/MgO/SiO(2)-SH catalyst using NaOH as precipitation agent, over which the turnover frequency (TOF) was much better than that of the sample without promotion. The temperature of the CO total conversion over the sample Au/MgO/SiO(2)-SH is about 250 K lower than that over the silica which directly supported gold catalyst. (C) 2011 Published by Elsevier B.V.