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The electronic structure of active metal centers plays an indispensable role in regulating catalytic reactivity in heterogeneous catalysis, developing other metals as promoters to decorate electronic state is a common strategy, while non-metal component of carbon as electronic additives to regulate d-band center has rarely been studied in thermal-catalysis field. Herein, we report electron-deficient tetrahedral Co(II) (Td-cobalt(II)) centers through carbon-layer modulation for propane dehydrogenation (PDH). It is indicated that bifunctional sites of both Td-cobalt(II) and metallic-cobalt are designed, and the in situ generated carbon through the disproportionation of CO on metallic-cobalt can cover the inactive metallic-cobalt and tailor d-band of active Td-cobalt(II) simultaneously. More importantly, the pre-deposited carbon-layer is proposed to decrease electron density of Td-cobalt(II) and make d-band center closer to Fermi level, consequently promotes C-H activation in PDH reaction. This study provides new perspective for the utilization of inactive carbon as electronic promoters and unlocks new opportunity to fabricate efficient PDH and other heterogeneous catalysts.

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High concentration of H2S in acidic natural gas will lead to poisoning of catalysts for hydrogen production by methane steam reforming, thus limiting the further use of natural gas. Reforming CH4 by H2S can be considered as an alternative route to hydrogen production from methane. This process not only achieves the removal of H2S but also obtains chemical raw material CS2 and clean energy H2. By impregnating the Mo source on SiO2 treated with hydrogen peroxide and then using the catalyst in the CH4/H2S reforming reaction, we surprisingly found that the conversion rate of CH4 and H2S increased from 28 and 32% to 34% and 43%, respectively, after hydrogen peroxide treatment. The H2 production rate and the yield of CS2 increased from 20 mmolH2/(gMo*min) and 52% to 30 mmolH2/(gMo*min) and 65%, respectively. Combining with characterization methods such as X-ray diffraction (XRD), hydrogen temperature programmed reduction (H2-TPR), 1H-based solid-state nuclear magnetic resonance (1H MAS NMR), X-ray photoelectron spectroscopy (XPS), Raman spectra (RS), and transmission electron microscopy (TEM), we found that the hydroxyl concentration of the support increased after hydrogen peroxide treatment, which led to the strengthening of the force between the metal and the support, which was easy to form low-level and small-size MoS2, exposing more active sites, and further improving the catalytic activity. This method provides a new idea for hydrogen production by CH4/H2S reforming and the development of high-performance MoS2-based catalysts.

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Highly dispersed metal sites on the surface of silica, achieved from immobilization of metal precursor within hydroxyl groups, has gained increasing attention in the field of heterogeneous catalyst. However, the special role of adsorbed water derived by hydroxyl groups on the silica is generally ignored. Herein, a new understanding of adsorbed water on the formation of highly dispersed tetrahedral Co(II) (Td-cobalt(II)) sites is illustrated. It is indicated that sufficient adsorbed water induces the transformation of precursor of Co(NO3)2 into intermediate of [Co(H2O)6]2+. Subsequently, [Co(H2O)6]2+ makes the highly dispersed Td-cobalt(II) sites to be available during direct H2-reduction process. A systematic characterization and DFT calculation prove the existence of the adsorbed water and the importance of the intermediate of [Co(H2O)6]2+, respectively. The as-synthesized catalyst is attempted to the propane dehydrogenation, which shows better reactivity when compared with other reported Co based catalysts.

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The one-step reaction approach from syngas with hydrogen sulfide (CO/H2/H2S) over potassium (K) promoted Molybdenum disulfide (MoS2) materials can provide alternatives for the synthesis of methanethiol (CH3SH). However, the direct confirmation and determination of the real active nature of K-induced 2H and 1T'-MoS2 for this reaction and the corresponding phase transformation behavior and origin of K-induced 2H-MoS2 from/to 1T'-MoS2 remains unclear. Herein, we proved at the atomic level the precise position of K over 1T'-MoS2 and 2H-MoS2 species using the technique of HAADF-STEM. A relationship between K-induced 1T' and 2H-MoS2 phases and the catalytic property to synthesize CH3SH was established, and K-intercalated 1T'-MoS2 phase was confirmed to have excellent catalytic performances. Moreover, the behavior, origin, and influencing factors of phase transformation of 2H-MoS2 from/to 1T'-MoS2 in the existence of K were well proved.

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Removal of toxic Cr (VI) from aqueous solutions using silicon-based adsorbents has been widely investigated. Meanwhile, contradictory between highly dispersed active Cr species and high Cr loading over commercial Cr-based catalyst was inevitable. In this work, amino-assisted electrostatic adsorption from toxic Cr (VI) treatment was developed to prepare highly dispersed Cr oxides catalysts supported on MCM-41. The Cr loading was as high as 15 wt%, and structure characters of the catalysts were well-reserved. As a result, electrostatic adsorption and subsequent complexation from negatively charged Cr (VI) species and positively charged ammonium groups made a positive contribution to the appearance of highly dispersed mono Cr species, which gave rise to improved non-oxidative propane dehydrogenation (PDH) activity. In contrast, the agglomeration of Cr species and lower PDH activity were observed on the sample synthesized using the traditional wet impregnation method. Besides, the transformation of Cr (VI) to active Cr (III) sites over the catalyst was proved by the designed in-situ H2-TPR, ex-situ UV-vis and Raman spectra results. This procedure reflects a new avenue of green chemistry, which can recycle waste Cr adsorbents as efficient PDH catalysts.

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Highly dispersed chromium (Cr)-based catalysts are promising candidates for the catalytic dehydrogenation of propane (DHP). However, the easier aggregation of Cr species into crystalline Cr2O3 at the high-temperature calcination and reaction process is a big challenge, which severely restricts the improvement of activity and stability of the DHP reaction. Herein, a flowing-air-induced transformation method was first proposed, and the catalytic performance of the prepared Cr/MCM-41 catalysts was found to be significantly improved compared to that of the Cr-based catalyst prepared by the traditional calcination method, even better than that of most of the reported Cr-based catalysts and some noble metal-based catalysts. X-ray absorption spectroscopy and in situ Raman spectroscopy as well as other characterization techniques demonstrated that the in situ calcination in flowing air could not only effectively restrain the conversion of Cr(VI) into Cr(III) but also largely improve the dispersion of Cr species. Furthermore, DHP activity is found to have a positive correlation with the amount of monomeric Cr(VI) species, which is proved to be the precursor of active coordinatively unsaturated Cr sites. Our proposed flowing-air-induced transformation method provides a general strategy for preparing the highly dispersed Cr-based catalysts and other metal oxide materials with varied valence and exhibits potential application prospects in industry.

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Recycling hazardous gas of H2S is one of the most important strategies to promote sustainable development. Herein, a novel method regarding purifying H2S is proposed by using yellow phosphorus and phosphate rock slurry as absorbent. The H2SO4, formed in situ by H2S conversion, can be devoted to decompose phosphate rock, and the spent absorption slurry was applied as raw material for the production of phosphorus chemical products. According to the characterization analysis, it was found that H2S was first oxidized to SO2 via O2 as well as O3 induced by P4. Subsequently, the generated SO2 dissolved rapidly in water to form H2SO4, and then reacted with the main component of phosphate rock, CaMg(CO3)2. Most notably, the active substances, such as, O3, SO4•- and OH•, produced in the reaction process, can oxidize H2S and HS- to these sulfur products. In addition, trace amounts of Fe3+ and Mn2+ that were dissolved from phosphate rock displayed a promotional effect on the formation of active substances. Consequently, as high as 85% of H2S removal efficiency can be obtained even under acidic condition and low temperature. The proposed H2S purification method offers a promising option for sulfur recovery and H2S pollution control.

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The emission of SO2 and the disposal of waste phosphate mine tailings are generally regarded as two major environmental issues in phosphorus chemical activities. In this paper, an environmentally friendly and efficient route for removing SO2 from phosphorus chemical processes by using waste phosphate mine tailings as adsorbent was proposed. It was indicated that the desulfurization performance of the waste phosphate mine tailings was better than that of its raw ore. The characterization analysis illustrated that higher content of CaMg(CO3)2 was shown on the waste phosphate mine tailings, which played a dominant role in determining the better desulfurization activity. In contrast, the accumulation of PO43- and H+ ions resulted from the dissolution of Ca5(PO4)3F on the raw ore caused negative effect on SO2 removal. In the typical desulfurization system, the produced sulfuric acid from desulfurization process was used to decompose phosphate mine tailings, and these spent tailings can be subsequently applied as raw materials for the production of phosphorus products. As a result, the present approach can achieve the dual goal of reducing the cost of desulfurization process and recycling the waste tailings, which is of great environmental and economic significance.

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As to the treatment of sulfur containing VOCs (examples are compounds of CH3SH and C2H5SH), finding a catalyst with high performance is necessary. In this work, Cr(x)-Al2O3 (x = 1.0, 2.5, 5.0, 7.5 and 10 wt%) catalysts were synthesized, and their behaviors toward CH3SH and C2H5SH abatement were investigated. The results indicated that Cr(7.5)-Al2O3 exhibited higher activity than other samples and the reported catalysts, on which CH3SH could be almost completely converted at 375 °C, while the temperature for the reported catalysts was above 450 °C. Moreover, there was no obvious deactivation during 30 h on stream over Cr(7.5)-Al2O3, while only about 10 h was found on the reported CeO2 and HZSM-5 catalysts. The improvement in the catalytic performance could be explained by the important role of the Cr6+ species, while the state of Cr3+ was suggested to be ineffective in the degradation process. The identification of the active Cr sites was proved by the characterization measurements, and the control experiments by using mechanical mixtures of CrO3 or Cr2O3 with Al2O3 as well as the comparison studies between spent Al2O3 and spent Cr(7.5)-Al2O3 catalysts.

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The purpose of our study was to investigate the effects of the long noncoding RNA (lncRNA) ABHD11-AS1 on colorectal cancer (CRC) progression and further explore its possible underlying mechanisms. In the study, we found that ABHD11-AS1 was highly expressed in CRC tissues and cell lines. High ABHD11-AS1 expression was correlated with poor overall survival of patients with CRC. ABHD11-AS1 knockdown reduced CRC cell proliferation, in vitro invasion, and in vivo tumor growth. Investigation of the underlying mechanism showed that ABHD11-AS1 could act as a molecular sponge of miR-1254, and WNT11 was a downstream target of miR-1254 in CRC. Moreover, there was a negative association between ABHD11-AS1 expression (or WNT11) and miR-1254 in CRC tissues. The rescue assays showed that WNT11 overexpression partially rescued the effects of ABHD11-AS1 inhibition on CRC progression. Thus, we demonstrated that ABHD11-AS1 promotes CRC progression through the miR-1254-WNT11 pathway, which provides a new insight into the therapeutic strategies for CRC.

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BACKGROUND Recent studies showed low expression of microRNA (miR)-101 in various malignancies. However, the association of serum miR-101 and colorectal cancer (CRC) remains unknown. We investigated diagnostic and prognostic significance of serum miR-101 in CRC. MATERIAL AND METHODS A total of 263 consecutive CRC patients and 126 healthy controls were enrolled in this study. Serum miR-101 levels were measured using real-time quantitative reverse transcription polymerase chain reactions. The association between serum miR-101 level and survival outcome was analyzed. RESULTS Serum miR-101 in CRC patients was significantly lower than in healthy volunteers (P<0.001). Low serum miR-101 level was significantly associated with advanced cancer stage. Moreover, survival analysis demonstrated that patients with a low serum miR-101 had poorer 5-year overall survival than patients with a high serum miR-101 level (p=0.041). Serum miR-101 level also were confirmed as an independent risk factor for CRC in multivariate analysis (hazard ratio, 1.468; 95%CI, 0.981-1.976; p<0.001). CONCLUSIONS Serum miR-101 level was significantly downregulated in CRC patients and was closely correlated with poor clinical outcome, suggesting that serum miR-101 might be a useful diagnostic and prognostic marker for CRC.

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Waste adsorbents generated from treating Cr(VI)-containing wastewater are hazardous materials and generally landfilled or treated by acid or base desorption, with concomitant high cost and toxic effects. The present work shows that these Cr adsorbents can be reused as highly efficient catalysts for treating sulfur-containing VOCs (CH3SH), not only avoiding the economic and environmental impact from the conventional approaches, but also achieving the efficient treatment of sulfur-containing waste gas. Importantly, these reused Cr adsorbents exhibit enhanced activity and stability compared with the catalysts reported elsewhere, indicating a new avenue of green chemistry. The highly toxic adsorbed Cr(VI) species are reduced to a Cr2O3 crystalline phase by calcination and finally immobilized as a Cr2S3 solid phase while converting and eliminating CH3SH. Still, the presence of Cr(VI) species on the reused Cr adsorbent provides enough reactive sites for reaction, but high concentration of Cr(VI) species causes serious accumulation of coke deposit on the catalyst, leading to fast deactivation of the catalyst.

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