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The photocatalytic activity of CdS/P25 hybrid catalysts was studied under visible-light irradiation. The CdS quantum dots sensitized P25 (CdS QDs-P25) showed extremely enhanced activity in the reduction of o-chloronitrobenzene (o-CNB) by comparing to CdS–P25 prepared by the direct deposition–precipitation method in the presence of HCOOH. The synergistic effects between CdS QDs and P25 were beneficial for the separation of photogenerated carriers in space and thus the combination of photoelectrons and holes was prevented, and the CdS QDs could provide more photocharges than CdS due to the particle size effect. Furthermore, the process of photocatalytic reduction in the present system was investigated, under visible-light irradiation, the photogenerated electrons transferred from the valence band (VB) to the conduction band (CB) of CdS QDs, and injected into the CB of inactivated P25. Meanwhile, the holes generated in the VB of CdS QDs could oxidize HCOO− to give ṖCO2− and H+. Then, o-CNB was reduced to o-chloroaniline (o-CAN) by the couple of e− and ṖCO2− with H+. It is a significant method and a green process for hydrogenation of nitro compounds, which may have great potential applications in the reduction of various organic chemicals. [ABSTRACT FROM AUTHOR]

Highlights: [•] Supported polyethylene glycol stabilized Pt nanoparticles were prepared. [•] Selectivity of m-iodoaniline reached 99.3% for hydrogenation of m-iodonitrobenzene. [•] The dehalogenation and the accumulation of intermediates were simultaneously inhibited. [•] The addition of CO2 remarkably affected the reaction rate and the product selectivity. [•] The SPPN catalyst was stable and can be reused several times. [ABSTRACT FROM AUTHOR]

Highlights: [•] The addition of CO2 remarkably affected the reaction rate and product selectivity. [•] The decreased reaction rate is due to the formation of solid carbamate in the presence of CO2. [•] The yield of benzylamine was increased to >94.4% in the presence of CO2. [•] The presence of CO2 could prohibit the formation of dibenzylamine in organic solvents. [•] The acidic nature of H2O–CO2 benefited the elimination of NH3. [Copyright &y& Elsevier]

Highlights: [•] The activity of Ni–Ir/TiO2 catalyst was four times as high as that of the Ni/TiO2 catalyst. [•] The reducibility of Ni was improved as addition of tiny amount of Ir. [•] The hydrogen spillover from Ir to Ni occurred in Ni–Ir/TiO2 catalyst. [•] The electronic structure of the surface Ni atoms was modified upon the addition of Ir. [ABSTRACT FROM AUTHOR]

Abstract: In this work, CuO/ZnO/Al2O3 catalysts were prepared by adjusting the initial alkali concentration in the process of co-precipitation. The correlation between the structure and catalytic activity was studied, and the catalyst derived from LDHs (layered double hydroxides) structure exhibited the highest activity in the hydrogenation of fatty esters as well as high selectivity to fatty alcohol, producing fatty alcohol with a yield above 98%. The high catalytic performance was attributed to relatively high dispersion (small crystal size) and the high reducibility of copper species. In addition, the active species was discussed and the Cu+/Cu0 were supposed to be the active site for the present hydrogenation. [Copyright &y& Elsevier]

Abstract: Water as a green solvent to replace the conventional organic solvent presents many advantages in the organic synthesis. The hydrogenation of nitrobenzene in water has been investigated by using Ni/TiO2 catalyst in this work, and our main purpose was focused on the Ni/TiO2 catalyst activity and its stability improvement. The experimental results and analysis from the data of XRD, XPS, ICP revealed that the formation of nickel hydroxide from metallic nickel reacting with water caused a rapid deactivation of Ni/TiO2 catalyst. Based on these, we designed a catalyst with hydrophobic property to prevent the nickel active species to contact with water; thus, a hydrophobic carbon layer was coated on the surface of Ni/TiO2. As expected, the hydrophobic carbon was successfully coated on Ni/TiO2 catalysts by a hydrothermal method and they presented higher reactivity and improved stability in the present aqueous reaction system; nickel hydroxide was not detected on the used and water treated carbon-coated Ni/TiO2 samples. The improved abilities were attributed to the increased hydrophobicity of catalysts modified by carbon, which not only prevents water to contact with nickel catalytic species, but also protects the metallic nickel to be oxidized as it exposed to air. [Copyright &y& Elsevier]

Abstract: Co(OH)2 coated platinum nanoparticles Pt/Co(OH)2 were prepared by microwave assistance and hydrothermal method, and the prepared samples were composed of Pt nanoparticles with an average size of 1.8nm coated uniformly in the thin Co(OH)2 leaves based on the results of X-ray diffraction, transmission electron microscopy, scanning electron microscopy and X-ray photoelectron spectroscopy. The Pt/Co(OH)2 presented excellent catalytic performance in the chemoselective hydrogenation of halonitrobenzenes such as chloronitrobenzenes, bromonitrobenzene and iodonitrobenzene, and above 99.6% selectivity to haloanilines was achieved at complete conversion irrespective of the substrates used, even for iodonitrobenzene to which the dehalogenation is more easily to occur. Co(OH)2 was confirmed to prohibit the dehalogenation effectively, and the Pt/Co(OH)2 catalyst could be recycled for several times. [Copyright &y& Elsevier]

Urea derivatives are obtained in mild to good yield from the reactions of primary aliphatic amines with CO2in the absence of any catalysts, organic solvents or other additives. To optimize reaction conditions, experimental variables including temperature, pressure, the concentration of amine, reaction time etc.were studied. Satisfactory yields were obtained at the optimized conditions that are comparable to the presence of catalyst and solvent. The preliminary investigation of the reaction mechanism showed that alkyl ammonium alkyl carbamate was quickly formed as the intermediate, and then the final product was formed by the intramolecular dehydration. [ABSTRACT FROM AUTHOR]

Abstract: The hydrogenation of chloronitrobenzene to chloroaniline was investigated over Ni/TiO2 at 35°C in supercritical CO2 (scCO2), ethanol, and n-hexane. The reaction rate followed the order of scCO2 > n-hexane>ethanol. In scCO2, the selectivity to chloroaniline and to aniline over Ni/TiO2 were 97–99.5% and <1%, respectively, in the conversion range of 9–100%. The high chemoselectivity to chloroaniline cannot be achieved over Ni/TiO2 in ethanol and n-hexane. In situ high-pressure Fourier transform infrared measurements were made to study the molecular interactions of CO2 with the following reactant and reaction intermediates: chloronitrobenzene, chloronitrosobenzene, and N-chlorophenylhydroxylamine. The molecular interaction modifies the reactivity of each species and accordingly the reaction rate and the selectivity. The influence of Cl substituent on the interaction modes of CO2 with these reacting species is discussed. Possible reaction pathways for the hydrogenation of chloronitrobenzene in scCO2 over Ni/TiO2 are also proposed. [Copyright &y& Elsevier]

Abstract: Hydrogenation of maleic anhydride (MAH) with Pd/C catalysts in supercritical carbon dioxide (scCO2) was investigated. The selectivity for γ-butyrolactone (GBL) reached 97.3% in scCO2 at 100% conversion of MAH, which was notably higher than that of 77.4% obtained in organic solvent of ethylene glycol dimethyl ether (EGDME). The particle size of Pd exhibited large influence on the reaction rate and selectivity of GBL. Higher selectivity of GBL was obtained with Pd/C catalyst of smaller Pd particle size, and the rate of GBL selectivity increase as a function of CO2 pressure was found to be significantly correlated with Pd particle size. [Copyright &y& Elsevier]

Abstract: In the present work, platinum nanoparticles were prepared by in situ reduction with polyethylene glycols (PEGs). The catalytic performance of Pt nanoparticles immobilized in PEGs (Pt-PEGs) is discussed for the hydrogenation of o-chloronitrobenzene (o-CNB). A high selectivity to o-chloroaniline (o-CAN) of about 99.7% was obtained with the Pt-PEGs catalysts at the complete conversion of o-CNB, which is much higher than that (83.4%) obtained over the conventional catalyst of Pt/C. The Pt nanoparticles could be immobilized in PEGs stably and recycled for four times with the same activity and selectivity. It presents a promising performance in the hydrogenation and its wide application in catalytic reactions is expected. [Copyright &y& Elsevier]

The selective hydrogenation of nitrobenzene (NB) over Ni/γ-Al2O3 catalysts was investigated using different media of dense phase CO2, ethanol, and n-hexane. In dense phase CO2, the total rate of NB hydrogenation was larger than that in organic solvents under similar reaction conditions; the selectivity to the desired product, aniline, was almost 100% over the whole conversion range of 0–100%. The phase behavior of the reactant mixture in/under dense phase CO2 was examined at reaction conditions. In situ high-pressure Fourier transform infrared measurements were made to study the molecular interactions of CO2 with the following reactant and reaction intermediates: NB, nitrosobenzene (NSB), and N-phenylhydroxylamine (PHA). Dense phase CO2 strongly interacts with NB, NSB, and PHA, modifying the reactivity of each species and contributing to positive effects on the reaction rate and the selectivity to aniline. A possible reaction pathway for the hydrogenation of NB in/under dense phase CO2 over Ni/γ-Al2O3 is also proposed. [Copyright &y& Elsevier]

Abstract: Hydrogenation of o-chloronitrobenzene (o-CNB) to o-chloroaniline (o-CAN) with Pd/C has been investigated in supercritical carbon dioxide (scCO2) at 308K. The influences of several parameters such as CO2, H2 pressures, Pd metal particle size and reaction time have been discussed. CO2 pressure presented markedly effects on the reaction rate and product selectivity under the reaction conditions used, the selectivity to o-CAN at CO2 pressure from 8 to 13MPa (supercritical region) was larger than that at CO2 pressure below 6MPa (subcritical region). Moreover, the larger selectivity to o-CAN was obtained in scCO2 compared with that in ethanol. [Copyright &y& Elsevier]

Abstract: An efficient enantioselective catalyst of 5wt.% Ru/γ-Al2O3 modified with R,R-1,2-diphenylethylene-diamine ((R,R)-DPEN) for the hydrogenation of a non-activated aromatic ketone of acetophenone has been investigated, a relatively high enantiomeric excess (ee) of 60.5% was obtained at both the conversion and selectivity larger than 99%, it was about three times higher than the ee values reported up to now for acetophenone hydrogenation with the supported transition metal catalysts modified by chiral reagents. The influences of some reaction parameters such as phosphine ligand, substrate/catalyst/modifier molar ratios, base, solvent, pressure and reaction temperature have been discussed. The chiral modifier of (R,R)-DPEN was very important in controlling the enantioselectivity through adsorption competing with other substrates on the surface of active metal species. The phosphine ligand and base were also important and indispensable in the present reaction. [Copyright &y& Elsevier]

Abstract: The selective oxidation of cyclohexane to cyclohexanol and cyclohexanone is an important chemical process and it has been paid more attentions recently. In the present work, the stainless steel reactor wall was found to influence the selective oxidation of cyclohexane very significantly, and a quasi-crystalline Ti45Zr35Ni17Cu3 alloy with the similar compositions as the reactor wall was used as a catalyst for the cyclohexane oxidation, as expected, a higher activity was obtained with it. The present results open up a new avenue for developing new catalyst for alkane oxidation. [Copyright &y& Elsevier]

• A bonded PZT-rubber bearing structural dynamic interaction model was developed. • Shear stress effect on the electromechanical admittance (EMA) was analytically interpreted. • 3D finite element model of a full-sized rubber bearing was generated to detect shear stress. • Validated experiment was conducted on two plate rubber bearings for shear stress identification. • Analytical, numerical and experimental results indicated the effectiveness of the approach. This paper presented a preliminary study on the feasibility of shear stress identification in plate rubber bearings using surface-bonded piezoceramic (PZT) transducers. A PZT-rubber bearing structural dynamic interaction model was developed to analyze the shear stress effect on the electromechanical admittance (EMA, inverse of impedance) by introducing a mechanical impedance system consisting of parallel mechanical elements. 3D finite element (FE) model of a full-sized plate rubber bearing was generated to detect shear stress using the EMA signatures. Proof-of-concept experiment was finally conducted on two plate rubber bearings subjected to shearing force, during which the process was monitored by three PZT sheets arranged at different loci. Theoretical, numerical and experimental results demonstrated that identification results of PZT transducers were closely related to the PZT location, shear stress in rubber bearings were generally in linear relationship with the peak values of EMA spectrum and its statistically quantifiable indicators. [ABSTRACT FROM AUTHOR]

Lignin has long been regarded as waste, readily separated and discarded from the pulp and paper industry. However, as the most abundant aromatic renewable biopolymer in nature, lignin can replace petroleum resources to prepare chemicals containing benzene rings. Therefore, the high-value transformation of lignin has attracted the interest of both academia and industry. Nitrogen-containing compounds and functionalized materials are a class of compounds that have wide applications in chemistry, materials science, energy storage, and other fields. Converting lignin into nitrogenous chemicals and materials is a high-value utilization pathway. Currently, there is a large amount of literature exploring the conversion of lignin. However, a comprehensive review of the transformation of lignin to nitrogenous compounds is lacking. The research progress of lignin conversion to nitrogenous chemicals and functional materials is reviewed in this article. This article provides an overview of the chemical structure and types of industrial lignin, methods of lignin modification, as well as nitrogen-containing chemicals and functional materials prepared from various types of lignin, including their applications in wastewater treatment, slow-release fertilizer, adhesive, coating, and biomedical fields. In addition, the challenges and limitations of nitrogenous lignin-based materials encountered during the development of applications are also discussed. It is believed that this review will act as a key reference and inspiration for researchers in the biomass and material field. [ABSTRACT FROM AUTHOR]

Polyols such as 1,5-pentadiol, 1,6-hexanediol, and 1,2,6-hexanetriol are crucial chemicals, traditionally derived from non-renewable fossil sources. In the pursuit of sustainable development, exploring renewable and environmentally benign routes for their production becomes imperative. Furfural and 5-hydroxymethylfurfural are C5 and C6 biomass-derived platform molecules, which have potential in the synthesis of various polyols through hydrogenation and hydrogenolysis reactions. Currently, there is an extensive body of literature exploring the transformation of biomass-derived furan compounds. However, a comprehensive review of the transformation of furan compounds to polyols is lacking. We summarized the literature from recent years about the ring-opening reaction involved in converting furan compounds to polyols. This article reviews the research progress on the transformation of furfural, furfuryl alcohol, and 2-methylfuran to 1,2-pentadiol, 1,4-pentadiol, 1,5-pentadiol, and 1,2,5-pentanetriol, as well as the transformation of 5-hydroxymethylfurfural to 1,2-hexanediol, 1,6-hexanediol, and 1,2,6-hexanetriol. The effects of the supported Pd, Pt, Ru, Ni, Cu, Co, and bimetallic catalysts are discussed through examining the synergistic effects of the catalysts and the effects of metal sites, acidic/basic sites, hydrogen spillover, etc. Reaction parameters like temperature, hydrogen pressure, and solvent are considered. The ring opening catalytic reaction of furan rings is summarized, and the catalytic mechanisms of single-metal and bimetallic catalysts and their catalytic processes and reaction conditions are discussed and summarized. It is believed that this review will act as a key reference and inspiration for researchers in this field. [ABSTRACT FROM AUTHOR]

[Display omitted] • Ti-Fe 2 O 3 /CuPc/citrate-FeCo(OH) x photoanode has been successfully synthesized. • CuPc as hole transport layer effectively promotes charge separation of Ti-Fe 2 O 3. • citrate-FeCo(OH) x can serve as a bifunctional layer accelerates the extraction and injection of holes. • Ti-Fe 2 O 3 /CuPc/citrate-FeCo(OH) x exhibits lower charge transfer resistance and higher current density. The restricted performance of α-Fe 2 O 3 in photoelectrochemical (PEC) water splitting is currently constrained by the slow kinetics of water oxidation and the rapid charge recombination. Herein, we prepared a composite photoanode with molecular copper phthalocyanine (CuPc) as the hole transport layer and citric acid assisted FeCo(OH) x as the cocatalyst using a simple two-step method. The optimized Ti-Fe 2 O 3 /CuPc/citrate-FeCo(OH) x photoanode achieved an photocurrent density of 2.67 mA/cm−2 at 1.23 V vs. RHE, which is 6.5 times higher than pure Ti-Fe 2 O 3 and can maintain long-term stability. Detailed studies have shown that CuPc and Ti-Fe 2 O 3 can form an interface electric field for hole oriented transport, significantly improving the transfer of photogenerated carriers. The FeCo(OH) x coating assisted by citric acid deposition not only forms a conformal coating, but also acts as a bifunctional layer to quickly transfer holes from Ti-Fe 2 O 3 /CuPc to the electrolyte. It also significantly increases the reactive active sites and hydrophilicity of Ti-Fe 2 O 3 /CuPc, which further accelerates the water oxidation kinetics. This study provides a promising strategy for the development of an efficient and cost-effective photoanode and extends the design concept of a PEC water splitting device. [ABSTRACT FROM AUTHOR]

Chemoselective hydrogenation of water-insoluble aromatic nitro compounds can be achieved over Ni catalysts in a H2O–compressed CO2system at 35–50 °C without using any environmentally harmful solvent. The effective CO2pressure is much lower than the critical pressure of CO2. The hydrogenation of nitro group should be the rate-determining step. [ABSTRACT FROM AUTHOR]

Chemoselective hydrogenation of water-insoluble aromatic nitro compounds can be achieved over Ni catalysts in a H2O–compressed CO2 system at 35–50 °C without using any environmentally harmful solvent. The effective CO2 pressure is much lower than the critical pressure of CO2. The hydrogenation of nitro group should be the rate-determining step. [ABSTRACT FROM AUTHOR]

Background: The aim of this study was to investigate the relationship between tumor biology and values of cerebral blood volume (CBV), cerebral blood flow (CBF), mean transit time (MTT), time to peak (TTP), permeability surface (PS) of tumor in patients with glioma. Methods: Forty-six patients with glioma were involved in the study. Histopathologic and molecular pathology diagnoses were obtained by tumor resection, and all patients accepted perfusion computed tomography (PCT) before operation. Regions of interests were placed manually at tumor and contralateral normal-appearing thalamus. The parameters of tumor were divided by those of contralateral normal-appearing thalamus to normalize at tumor (relative [r] CBV, rCBF, rMTT, rTTP, rPS). The relationships of the parameters, world health organization (WHO) grade, molecular pathological findings were analysed. Results: The rCBV, rMTT and rPS of patients are positively related to the pathological classification (P < 0.05). The values of rCBV and rPS in IDH mutated patients were lower than those IDH wild-type. The values of rCBF in patients with MGMT methylation were lower than those MGMT unmethylation (P < 0.05). The MVD of TERT wild-type group was lower than TERT mutated group (P < 0.05). The values of rCBV were significant difference in the four molecular groups divided by the combined IDH/TERT classification (P < 0.05). The progression free survival (PFS) and overall survival (OS) were significant difference in the four molecular groups divided by the combined IDH/TERT classification (P < 0.05). Conclusions: Our study introduces and supports the changes of glioma flow perfusion may be closely related to its biological characteristics. [ABSTRACT FROM AUTHOR]

Monopile foundations are currently the most significant support form for offshore wind turbines. An experimental investigation of the vibrating monopile was conducted inside the cohesionless saturated sand bed to examine the pore water pressure oscillation response law and amplitude variation features around the monopile under the vibration effect. The experimental results indicate that the vibration loading force F p , vibration frequency f v and vibration amplitude A v have remarkable impacts on the various characteristics of the pore pressure response around the monopile foundation. The lower the vibration frequency, the more prominent is the delayed attenuation process during the oscillation cycle, and a succession of pore pressure sub-peaks develop near the phase end of the cycle period. Additionally, the pore pressure amplitude decay rate increases with increasing frequency as the depth of the seabed grows, and the pile side pore pressure shows a trend of increasing and then decreasing with frequency. • Using flume experiments, the seabed response characteristics around the monopile under the vibration action were investigated. • The effects of vibration loading force F p , vibration frequency f v and vibration amplitude A v on the variation characteristics of pore pressure response are further considered. • The pore pressure oscillation response law and amplitude change characteristics in the depth direction, horizontal direction and circular direction along the seabed were investigated in detail. [ABSTRACT FROM AUTHOR]

• The structure–activity relationship between ILs and separated azeotrope is explored. • An efficient MSED for azeotrope separation using ILs mixed solvent is proposed. • The proposed process is optimized by nonlinear multi-objective optimization. • The feasibility of the established process is evaluated from multiple perspectives. Efficient recovery of isopropyl acetate and isopropanol from wastewater during esterification is important. An efficient separation process using ionic liquid mixed solvent extractive distillation (MSED) to separate azeotropic mixtures was proposed. The selectivity of 169 ionic liquids was calculated based on the COSMO–segment activity coefficient model for prescreening ionic liquids. The influence of the structure of the ionic liquids on the separation performance was further explored through molecular dynamics to determine 1-ethyl-3-methylimidazole acetate ([EMIM][AC]) as the best solvent. The vapor–liquid equilibrium of the system under the influence of [EMIM][AC] was measured to verify the model used for the calculation. A multi-objective genetic algorithm was used for optimizing the process parameters with the total annual cost (TAC) and gas emission as objective functions. An energy-saving heat-pump-assisted heat-integrated extractive distillation (HPHIED) process was proposed to realize heat recovery in MSED. The results showed that the TAC and gas emissions of MSED were 26.83% and 25.32%, respectively, lower than those of the single-organic solvent extractive distillation process. The TAC and gas emissions of HPHIED process were 11.02% and 35.83%, respectively, lower than those of MSED. [ABSTRACT FROM AUTHOR]

[Display omitted] • Pt-Bi/TiO 2 was first time developed for the hydrogenation of NS to AS. • A high selectivity to AS of 96% was achieved over Pt-Bi/TiO 2 -1.5. • The terraces Pt sites transferred to low coordinated Pt sites with addition of Bi. • The low-coordinated Pt sites were responsible for the chemoselectivity of Pt-Bi/TiO 2. The selective hydrogenation of a molecule containing several unsaturated groups is a very important issue and has attracted much more attention in the chemical synthesis. Herein, a highly selective catalyst of Pt-Bi/TiO 2 was first time developed for the hydrogenation of 3-nitrostyrene (NS) to 3-aminostyrene (AS), with it an excellent selectivity to AS of 96% was achieved at the complete conversion. The influence of Bi on the catalytic performance was well discussed by using X-ray diffraction (XRD), transmission electronic microscopy (TEM), CO pulse chemisorption, hydrogen temperature-programmed reduction (H 2 -TPR), X-ray photoelectron spectroscopy (XPS), diffuse reflectance Fourier transform infrared (DRFTIR) spectroscopy of adsorbed CO, and thermo gravimetric analysis (TGA) and experiment data. With increasing Bi loading, Bi-rich surface was formed, and the terraces sites of Pt disappeared as it transferred to the low coordinated Pt gradually. Thus, high selectivity of AS was obtained over Pt-Bi/TiO 2 for the hydrogenation of AS to 3-ethylaniline (EA) was lowered. [ABSTRACT FROM AUTHOR]

Intervertebral disc degeneration is a very common disease worldwide and the leading cause of low back pain. Long noncoding RNAs are novel players in intervertebral disc degeneration and have multiple functions. This study explored the role of long noncoding RNA HCG18 in regulating extracellular matrix (ECM) degradation in nucleus pulposus cells (NPCs) during intervertebral disc degeneration. NPCs were subjected to interleukin-1β to induce a degenerative model of NPCs. Cell viability was assessed using Cell Counting Kit-8 assay. Messenger RNA and protein expressions were examined by real-time quantitative polymerase chain reaction and Western blot. The location of HCG18 was determined by nucleocytoplasmic separation assay. The binding relationships between HCG18 , MIR4306, and EPAS1 were verified by dual luciferase reporter gene assay and/or RNA immunoprecipitation assay. HCG18 was highly expressed in interleukin-1β–induced degenerated NPCs, which was associated with reduced collagen II and aggrecan expression and increased MMP-13 and ADAMTS-4 expression. HCG18 knockdown could remarkably inhibit ECM degradation in IL-1β–induced degenerated NPCs, while HCG18 overexpression had the opposite effect. Our molecular study further revealed that HCG18 could sponge MIR4306 , and HCG18 knockdown could suppress ECM degradation in degenerated NPCs by elevating MIR4306 expression. In addition, EPAS1 was identified as the direct target of MIR4306. As expected, MIR4306 overexpression inhibited ECM degradation in degenerated NPCs by downregulating EPAS1. HCG18 promoted ECM degradation in degenerated NPCs via regulation of the MIR4306 / EPAS1 axis. [ABSTRACT FROM AUTHOR]

Catalytic conversion of furfural and its derivatives to value-added C 5 molecules has attractive much attention in the field of biomass conversion. In this paper, the selective hydrogenolysis of tetrahydrofurfuryl alcohol to 1,5-pentanediol has been studied over a series of PrO x promoted Ni/Al 2 O 3 catalysts. The catalytic performances and the promoting effects of PrO x , as well as the role of Ni and PrO x species have been discussed. The surface properties and structure of catalysts were examined by TEM, XRD, XPS, H 2 -TPR, H 2 -TPD, in-situ DRIFTS, etc. The presence of PrO x species promotes the reaction rate and changes product selectivity significantly, and a 79.2% 1,5-pentanediol selectivity can be obtained at 88.4% conversion over the NiPr 1.2 /Al 2 O 3 catalyst. The synergistic effect between defect-rich PrO x and the adjacent active Ni species has been confirmed to contribute to the superior catalytic performances. These results provide useful knowledge for the activation of cyclic ether bonds and the design of heterogeneous catalysts with lanthanide oxide supports. Defect-rich PrO x enhances the catalytic performance of Ni/Al 2 O 3 in the selective hydrogenolysis of tetrahydrofurfuryl alcohol to 1,5-pentanediol by promoting the adsorption of THFA on the catalyst. [Display omitted] • High 1,5-PDO selectivity can be achieved over the NiPr x /Al 2 O 3 catalyst. • 79.2% 1,5-PDO selectivity was obtained at 88.4% THFA conversion. • The Ni-PrO x interfacial active sites are crucial for the activation of cyclic ether bond. • The defect-rich PrO x facilitates the THFA adsorption. [ABSTRACT FROM AUTHOR]

Generally, the fast ion/electron transport and structural stability dominate the superiority in lithium-storage applications. In this work, porous carbon nanotubes decorated with nanosized CoFe 2 O 4 particles (p-CNTs@CFO) have been rationally designed and synthesized by the assistance of supercritical carbon dioxide (scCO 2 ). When tested as anode materials for lithium-ion batteries, the p-CNTs@CFO composite exhibits outstanding electrochemical behavior with high lithium-storage capacity (1077 mAh g −1 after 100 cycles) and rate capability (694 mAh g −1 at 3 A g −1 ). These outstanding electrochemical performances are attributed to the synergistic effect of porous p-CNTs and nanosized CFO. Compared to pristine CNTs, the p-CNTs with substantial pores in the tubes possess largely increased specific surface area and rich oxygen-containing functional groups. The porous structure can not only accommodate the volume change during lithiation/delithiation processes, but also provide bicontinuous electron/ion pathways and large electrode/electrolyte interface, which facilitate the ion diffusion kinetics, improving the rate performance. Moreover, the CFO particles are bonded strongly to the p-CNTs through metal-oxygen bridges, which facilitate the electron fast capture from p-CNTs to CFO, and thus resulting in a high reversible capacity and excellent rate performance. Overall, the porous p-CNTs provide an efficient way for ion diffusion and continuous electron transport as anode materials. [ABSTRACT FROM AUTHOR]

Nickel multiply-twinned particles (Ni MTPs) imbedded onto ZSM-5 were prepared, and their formation and chemical and electronic properties were characterized by HRTEM, XPS, CO-FTIR, and H 2 -TPD. HRTEM showed the formation of Ni MTPs with triangular, square, hexagonal, and spherical shapes. The multiply-twinned particles were composed of f . c . c . nanocrystals dominated by (1 1 1) crystal face. Ni MTPs indicate an enhanced CO adsorption capability as compared with ordinary Ni particles. Ni MTPs were electron deficient and inherently strained, which is responsible for high catalytic activity in the hydrolytic hydrogenation of cellulose. [ABSTRACT FROM AUTHOR]

Nickel based catalyst is of interest in the industrial catalytic processes, and it is always modified by doping a second element to improve its catalytic properties. Understanding the role of dopant is extremely helpful in tailoring the active centers. In this work, Zn could induce a significant improvement of the catalytic performance of NiAl for the hydrogenolysis of glycerol. The Zn doped ZnNiAl catalysts exhibited high activity and the improved selectivity to 1,2-propanediol, it was about 2 times higher than the original ones. The ZnNi alloy formed in ZnNiAl was responsible for the noticeable catalytic performance. They preferred to coordinate with the end hydroxyl group of glycerol, promoted the cleavage of C O bond in glycerol, and resulted in the dominant formation of 1,2-propanediol. The findings described here will provide a useful knowledge for rational design of nickel-based catalysts, as well as reveal a new reaction model for the hydrogenolysis of glycerol. [ABSTRACT FROM AUTHOR]

2D–3D mixed tin halide perovskites are outstanding candidate materials for lead‐free perovskite solar cells (PSCs) due to their improved stability and decreased trap density in comparison with their pure 3D counterparts. However, the mixture of multiple phases may lead to poor charge transfer across the films and limit the device efficiency. Here, a stacked quasi‐2D (down)–3D (top) double‐layered structure in perovskite films prepared via vacuum treatment is demonstrated, which can result in a planar bilayer heterojunction. In addition, it is found that the introduction of guanidinium thiocyanate (GuaSCN) additive can improve the crystallinity and carrier mobility in the 2D perovskite layer and passivate defects in the whole film, leading to a long carrier lifetime (>140 ns) in photoluminescence measurements. As a result, the PSCs show a high open circuit voltage (VOC) up to 1.01 V with a voltage loss of only 0.39 V, which represents the record values ever reported for tin‐based PSCs. The champion device exhibits a power conversion efficiency (PCE) of 13.79% with decent stability, retaining 90% of the initial PCE for 1200 h storage in N2‐filled glovebox. [ABSTRACT FROM AUTHOR]

Highlights: [•] Hexitols were produced over Ni/ZSM-5 with a high yield of 82%. [•] Hexitols yield depended on the hydrogenation/dehydrogenation activity of catalyst. [•] The activation energy of hydrogenation and dehydrogenation was estimated. [•] The synergistic effect of Ni and acid–base sites of support was confirmed. [•] Mechanism of cellulose conversion was discussed based on the basic step reactions. [ABSTRACT FROM AUTHOR]

• RuRe/ZSM-5(18) was an efficient catalyst for production of biofuels from fatty esters/acids. • n -C 12 H 26 was produced with a 95.2 % yield in the hydrodeoxygenation of C 11 H 23 COOCH 3. • The synergy of ReO x and Brønsted acid induced metallic Ru to be electron-deficient. • The electron-deficient Ru inhibited decarbonylation but facilitated hydrogenation. • ReO x facilitated the adsorption of carboxyl while Brønsted acid promoted dehydration. The hydrodeoxygenation of fatty acids and esters is a critical pathway to produce biofuels. We report an efficient RuRe/ZSM-5(18) catalyst for hydrodeoxygenation of methyl laurate, the selectivity of n -C 12 H 26 reached up to 95.2 % at complete conversion under the reaction conditions of 200 °C, 3 MPa H 2 , 3 h. The contribution of ReO x and acid sites was discussed from the perspective of dynamics and thermodynamics. ReO x was available for the adsorption of substrate and intermediates, the acidity from ReO x species and ZSM-5 are conducive to the cleavage of C O bond. The synergistic effects of ReO x and Brønsted acid sites induced Ru0 species to be electron-deficient, which preferred to adsorb aldehyde group in a linear adsorption configuration and facilitated for the hydrogenation of the aldehyde intermediate to alcohol, followed by dehydration to produce hydrocarbons. Thus, RuRe/ZSM-5(18) catalyst presented superior activity and chemoselectivity in the hydrodeoxygenation of methyl laurate as well as a series of fatty acids and esters without loss in carbon numbers in reactant. [ABSTRACT FROM AUTHOR]

Abstract: The reduction of an α,β-unsaturated aldehyde, citral, was investigated over a 10wt% Pd catalyst under transfer hydrogenation (TH) conditions in a closed system with microwave assistance. Surprisingly, it was found that hydrogen was produced quite fast under the microwave irradiation during the reaction, and the reduction of citral was proved to go mainly through consecutive pathways of hydrogen production – hydrogenation rather than those commonly considered for TH reactions. Similar reaction pathways were also observed with a homogeneous catalyst of [RuCl2(C6H6)]2 and other typical hydrogen donors like formate salts and isopropanol, which are usually used in the typical transfer hydrogenations. [Copyright &y& Elsevier]

Abstract: The fabrication of nanostructured materials from hydrous inorganic metal salt processed in supercritical CO2 (scCO2) expanded liquids has advantages to obtain good results. However, the behavior of the inorganic salts and the detailed reaction mechanism are still unknown up to now. In this work, the actual behavior of hydrous inorganic metal salts in CO2 expanded ethanol at the temperature of 50–200°C, including the phase behavior, deposition mechanism, reaction rate and the effect of templates on the deposition were systematically investigated by using XRD, FTIR, CHN-analysis, TGA, ICP-AES. A series of experimental parameters such as CO2 flow rate, expand procedure, reaction temperature and time have been discussed, as well as the roles of CO2 and H2O (often originated from salts and/or solvent but always neglected) were studied in this contribution. Significantly, a coordination–decomposition (C–D) was proved to be the converting mechanism for the precipitation of the hydrous inorganic metal salts, rather than the fuzzy decomposition. [Copyright &y& Elsevier]