Insight into the Effect of Promoter Mn on Ethanol Formation from Syngas on a Mn-Promoted MnCu(211) Surface: A Comparison with a Cu(211) Surface

Density functional theory calculations have been employed to investigate the effect of promoter Mn on ethanol formation from syngas on a Mn-promoted MnCu(211) surface. Our results show that CO + 3H → CHO + 2H → CH₂O + H → CH₃O is an optimal pathway for the overall CO conversion. Starting with CH₃O, CH₃ is formed via CH₃O → CH₃ + O. Then, CHO insertion into CH₃ can form CH₃CHO, and further, CH₃CHO is successively hydrogenated to ethanol via CH₃CH₂O intermediate. Meanwhile, CH₃OH is formed via CH₃O + H → CH₃OH. Compared to the pure Cu(211) surface, CH₃ formation is found to be energetically compatible with CH₃OH formation on the MnCu(211) surface, which can lead to more CH₃ sources and less CH₃OH; thus, the productivity and selectivity of ethanol can be improved. On the other hand, starting from CH₃, the MnCu(211) surface is more favorable for CHO insertion into CH₃ to CH₃CHO in comparison with CH₃ hydrogenation, dissociation and coupling to CH₄, CH₂, and C₂H₆ due to their high activation barriers; namely, the MnCu(211) surface exhibits a better selectivity toward C₂ oxygenates rather than hydrocarbons. As a result, we can show that, by introducing promoter Mn into Cu catalyst, the productivity and selectivity to ethanol from syngas can be effectively improved

Insight Into the Effect of CuNi(111) and FeNi(111) Surface Structure and Second Metal Composition on Surface Carbon Elimination by O or OH: A Comparison Study with Ni(111) Surface

A density functional theory (DFT) calculation has been carried out to systematically investigate the mechanism of surface carbon elimination by O and OH on both the alloy FeNi(111) and CuNi(111) surfaces, including the homogeneous and the segregated surfaces, respectively; meanwhile, the obtained results are compared with those on the pure Ni(111) surface in order to probe into the effects of CuNi(111) and FeNi(111) surface structure and second metal composition on the performance of surface carbon elimination. Our results show that compared to the pure Ni(111) surface, the introduction of Fe into Ni increases the adsorption of O, OH, and C species, while it weakens the adsorption of CO and COH; the incorporation of Cu into Ni decreases the adsorption ability of C, O, OH, CO, and COH species. The mechanism of surface carbon elimination by O and OH shows that OH species is more effective for carbon elimination than O species on Ni(111), CuNi(111) surface and the segregated FeNi(111) surface; meanwhile, CuNi(111) and FeNi(111) surface structure and second metal composition have obvious effect on the performance of carbon elimination. Compared to Ni(111), FeNi(111) surface is not favorable for carbon elimination, while CuNi(111) surface is beneficial for carbon elimination, in which the Cu enriched surface is much more favorable than the 1:1 Cu surface and the pure Ni(111), indicating that the segregated CuNi(111) surface with Cu enrichment significantly accelerates carbon elimination. Moreover, the good linear relationship exists between the average adsorption energy of C + O or C + OH and the activation barrier of the C + O­(OH) reaction. As a result, once carbon is formed on the segregated CuNi alloy surface with Cu enrichment, carbon deposits can be timely eliminated, which can well explain the reported experimental facts that CuNi bimetallic catalysts with Cu surface enrichment display excellent carbon-resistance ability in CH₄/CO₂ reforming

First-Principles Study about the Effect of Coverage on H₂ Adsorption and Dissociation over a Rh(100) Surface

The adsorption and dissociation of H₂ with different coverages over the Rh(100) surface have been systematically investigated to probe into the effect of coverage on H₂ adsorption and dissociation. Here, the results are obtained using the density functional theory (DFT) method together with the periodic slab model. Both the parallel and vertical modes of H₂ adsorption on the Rh(100) surface have been identified, and the detailed studies corresponding to H₂ adsorption and dissociation at different coverages are presented. Our results show that the parallel mode of a single H₂ adsorbed on the Rh(100) surface is more favorable than the vertical mode, in which the top site is the most stable adsorption site. However, the parallel modes of single H₂ adsorbed at the bridge and 4F hollow sites, as well as the vertical mode of single H₂ adsorbed at the 4F hollow site are all the dissociative adsorption. On the other hand, with the increasing of H₂ coverage from low to high, the most stable adsorption configurations of H₂ is the parallel adsorption mode at the top site, and the adsorption energies of these adsorbed H₂ molecules will decrease gradually until the saturated adsorption with H₂ coverage of 6/12 ML, further, the dissociation of these adsorbed H₂ molecules is more favorable both kinetically and thermodynamically than their desorption, suggesting that the dissociation of the adsorbed H₂ molecule is more favored than their desorption. Finally, considering the dissociative adsorption of the single H₂ molecule with the parallel modes at the bridge and 4F hollow sites, as well as the vertical mode at the 4F hollow site, our results still show that the adsorptions of H₂ with different coverages at these sites are still the dissociative adsorption with the dissociative H atoms adsorbed on the Rh surface. Therefore, H₂ dominantly exists in the form of H atoms on Rh catalyst under realistic conditions

A DFT Study on the Catalytic CO Oxidative Coupling to Dimethyl Oxalate on Al-Doped Core–Shell Pd Clusters

A series of core–shell catalysts aiming at CO oxidative coupling to dimethyl oxalate (DMO) were constructed, and effects of the second metal doping and surface structures on the reaction activity and favorable reaction path were investigated by using the density functional theory (DFT) method. Pd₁₃, Al@Pd₁₂, and Ag@Pd₁₂ were first studied to find the proper doping metal. Our results showed that the activity of CO oxidative coupling to DMO follows the order of Al@Pd₁₂ > Pd₁₃ > Ag@Pd₁₂, and the same result was also obtained via the electronic analysis. In addition, Al₆@Pd₃₂ and Al₁₃@Pd₄₂ catalysts with higher doping ratio and lower cost than that of Al@Pd₁₂ were selected to examine the influence of surface structure on the reaction activity. It showed that CO + CH₃O → COOCH₃ + CO → OCCOOCH₃ + CH₃O → DMO is the favorable pathway on the (100) surface of Al₆@Pd₃₂ catalyst, while CO + CH₃O → CO + CH₃O (COOCH₃) → COOCH₃ + COOCH₃ → DMO is the optimal pathway on the (111) surface of Al@Pd₁₂ and Al₁₃@Pd₄₂, which indicated that the surface structure of catalysts affected the preferable pathway of DMO formation. Moreover, activities of CO oxidative coupling to DMO on AlPd core–shell catalysts followed the order of Al@Pd₁₂ > Al₁₃@Pd₄₂ > Al₆@Pd₃₂. In addition, Al₁₃@Pd₄₂ also exhibited a good selectivity between DMO and DMC. Thus, Al₁₃@Pd₄₂ is a proper catalyst with high activity, high selectivity, and low cost because of high Al:Pd ratio

Image1_FDX1 expression predicts favourable prognosis in clear cell renal cell carcinoma identified by bioinformatics and tissue microarray analysis.TIF

Ferredoxin 1 (FDX1), an iron-sulphur protein, is responsible for electron transfer in a range of metabolic redox reactions. Clear cell renal cell carcinoma (ccRCC) is an aggressive cancer characterised by metabolic reprogramming, and FDX1 is a critical regulator of cuproptosis. However, the expression profile and prognostic value of FDX1 associated with clinicopathological features in ccRCC remain largely unelucidated. In this study, we integrated a series of public bioinformatic analysis to explore the mRNA and protein profiles of FDX1 across human cancers and cell lines and validated its expression and prognostic value, especially in ccRCC. In this study, FDX1 mRNA and protein expression were aberrantly downregulated and associated with ccRCC grade, stage, and nodal metastasis, whereas in adjacent non-tumour kidney tissue, it was abundantly expressed and cytoplasmically localised in renal tubular epithelial cells. Multivariate analysis indicated that low FDX1 expression contributed to unfavourable overall and disease-free survival. The functional enrichment of FDX1 co-expressed genes in ccRCC involved mainly mitochondrial dysfunction in various metabolic processes and biological oxidation, besides iron-sulphur cluster biogenesis. Furthermore, FDX1 modulates immunological infiltration to affect prognosis. Thus, FDX1 downregulation is mechanistically because of ccRCC tumourigenesis and is a promising prognostic biomarker to stratify patients with ccRCC.</p

Table1_FDX1 expression predicts favourable prognosis in clear cell renal cell carcinoma identified by bioinformatics and tissue microarray analysis.XLSX

Ferredoxin 1 (FDX1), an iron-sulphur protein, is responsible for electron transfer in a range of metabolic redox reactions. Clear cell renal cell carcinoma (ccRCC) is an aggressive cancer characterised by metabolic reprogramming, and FDX1 is a critical regulator of cuproptosis. However, the expression profile and prognostic value of FDX1 associated with clinicopathological features in ccRCC remain largely unelucidated. In this study, we integrated a series of public bioinformatic analysis to explore the mRNA and protein profiles of FDX1 across human cancers and cell lines and validated its expression and prognostic value, especially in ccRCC. In this study, FDX1 mRNA and protein expression were aberrantly downregulated and associated with ccRCC grade, stage, and nodal metastasis, whereas in adjacent non-tumour kidney tissue, it was abundantly expressed and cytoplasmically localised in renal tubular epithelial cells. Multivariate analysis indicated that low FDX1 expression contributed to unfavourable overall and disease-free survival. The functional enrichment of FDX1 co-expressed genes in ccRCC involved mainly mitochondrial dysfunction in various metabolic processes and biological oxidation, besides iron-sulphur cluster biogenesis. Furthermore, FDX1 modulates immunological infiltration to affect prognosis. Thus, FDX1 downregulation is mechanistically because of ccRCC tumourigenesis and is a promising prognostic biomarker to stratify patients with ccRCC.</p

Bilateral Synchronous Sporadic Renal Cell Carcinoma: Retroperitoneoscopic Strategies and Intermediate Outcomes of 60 Patients

<div><p>Objective</p><p>To evaluate the presentation, management, pathology, and functional and oncological outcomes of patients undergoing retroperitoneoscopic treatment of bilateral synchronous sporadic RCC at our institution.</p><p>Methods</p><p>We retrospectively evaluated the records of 60 patients with bilateral synchronous sporadic RCC who underwent retroperitoneoscopic treatment at the General Hospital of People's Liberation Army from 2008 to 2014. The estimated glomerular filtration rate was calculated and compared among different surgical procedures. The overall survival and recurrence free survival were assessed based on information from recent follow-up.</p><p>Results</p><p>Fifty-six patients underwent bilateral retroperitoneoscopic surgeries in staged procedures, and four patients underwent bilateral retroperitoneoscopic surgeries in simultaneous procedures. Among the former group of patients, 34 underwent bilateral partial nephrectomy, 12 underwent radical nephrectomy followed by partial nephrectomy, and 10 underwent partial nephrectomy followed by radical nephrectomy. Bilateral partial nephrectomy can better preserve renal function (p = 0.040) and the sequence of partial nephrectomy and radical nephrectomy did not affect functional outcomes (p = 0.790). One patient undergoing simultaneous procedures developed acute renal failure and required temporary hemodialysis. At 3 and 5 years, overall survival rates were 93.0% and 89.4%, and recurrence free survival rates were 90.5% and 81.6%. High nuclear grade (p = 0.014) was related to disease recurrence.</p><p>Conclusions</p><p>Staged bilateral partial nephrectomy was efficient in preserving renal function. The survival of patients with bilateral synchronous sporadic renal tumors was similar to that of patients with unilateral nonmetastatic tumors. Nuclear grade was an independent prognostic factor of disease recurrence.</p></div

Image2_FDX1 expression predicts favourable prognosis in clear cell renal cell carcinoma identified by bioinformatics and tissue microarray analysis.TIF

Ferredoxin 1 (FDX1), an iron-sulphur protein, is responsible for electron transfer in a range of metabolic redox reactions. Clear cell renal cell carcinoma (ccRCC) is an aggressive cancer characterised by metabolic reprogramming, and FDX1 is a critical regulator of cuproptosis. However, the expression profile and prognostic value of FDX1 associated with clinicopathological features in ccRCC remain largely unelucidated. In this study, we integrated a series of public bioinformatic analysis to explore the mRNA and protein profiles of FDX1 across human cancers and cell lines and validated its expression and prognostic value, especially in ccRCC. In this study, FDX1 mRNA and protein expression were aberrantly downregulated and associated with ccRCC grade, stage, and nodal metastasis, whereas in adjacent non-tumour kidney tissue, it was abundantly expressed and cytoplasmically localised in renal tubular epithelial cells. Multivariate analysis indicated that low FDX1 expression contributed to unfavourable overall and disease-free survival. The functional enrichment of FDX1 co-expressed genes in ccRCC involved mainly mitochondrial dysfunction in various metabolic processes and biological oxidation, besides iron-sulphur cluster biogenesis. Furthermore, FDX1 modulates immunological infiltration to affect prognosis. Thus, FDX1 downregulation is mechanistically because of ccRCC tumourigenesis and is a promising prognostic biomarker to stratify patients with ccRCC.</p

Preoperative aspects and dimensions used for an anatomical (PADUA) classification of renal tumors treated with different surgical procedures and sequences.

<p>Preoperative aspects and dimensions used for an anatomical (PADUA) classification of renal tumors treated with different surgical procedures and sequences.</p

Promotion of Anatase/Rutile Junction to Direct Conversion of Syngas to Ethanol on the Rh/TiO₂ Catalysts

Although significant efforts have been made for the direct syngas conversion to ethanol, ethanol yield remains low. Herein, we studied syngas conversion on the Rh/TiO2 catalysts with different TiO2 phase compositions. The ethanol selectivity and yield reached 34.9 and 19.4%, respectively, at a 55.7% CO conversion on the Rh/P25 catalyst. Among the supported single Rh catalysts, this is currently the highest reported ethanol yield. The catalyst also shows good stability. The mixture of anatase–rutile phases in the P25 promotes the electron transfer from P25 to Rh species because of the strong metal–support interaction. It boosts the Rh0 active site generation, the CO dissociation, and CHx species formation, which is the significant intermediate for ethanol formation. In contrast, the Rh supported on the pure phase anatase or rutile TiO2 presents poor ethanol yield, which mainly produces the Rh+ species. This study provides an effective method to improve the ethanol yield for direct syngas conversion