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The Cu/ZnO/Al2O3 catalysts prepared by co-precipitation method were used for the hydrogenation of methyl benzoate to benzyl alcohol. These catalysts were characterized at various stages of preparation by nitrogen adsorption-desorption, X-ray diffraction (XRD), hydrogen temperature-programmed reduction (H2-TPR), and X-ray photoelectron spectroscopy (XPS). The experimental results show that the addition of ZnO to the catalyst greatly improves the selectivity of benzyl alcohol. When the Cu/Zn/Al molar ratio is 2:2:1 and the calcination temperature of the catalyst is 650 °C, the catalyst exhibits very highly catalytic performance. In addition, the effects of reaction temperature, pressure and time were also investigated during the hydrogenation of methyl benzoate to benzyl alcohol. When the methyl benzoate was hydrogenated over this catalyst at 160 °C and 7 MPa of H2 for 10 h, the conversion of methyl benzoate can reach 93.89% and the selectivity of benzyl alcohol is 88%. This effectively catalytic performance can be attributed to the presence of highly dispersed and stable metallic copper nanoparticles, and the weak acidity of the catalyst surface. Besides, the reaction pressure and temperature play a crucial role in the conversion of methyl benzoate and the selectivity of benzyl alcohol.Graphical Abstract: Application of Cu/ZnO/Al2O3 catalyst in hydrogenation of methyl benzoate to benzyl alcohol. [ABSTRACT FROM AUTHOR]

[Display omitted] • Single-atom nanozyme-based electrochemical sensors have ultra-high sensitivity. • Electrochemical sensors for in-vivo small molecules detection are reviewed. • Electrochemical sensors are promising in health and food safety monitoring. • Practical application in health monitoring is discussed. • Optimization strategies to improve the sensing performance is proposed. Electrochemical sensors and biosensors play an important role in many fields, including biology, clinical trials, and food industry. For health and food safety monitoring, accurate and quantitative sensing is needed to ensure that there is no significantly negative impact on human health. It is difficult for traditional sensors to meet these requirements. In recent years, single-atom nanozymes (SANs) have been successfully used in electrochemical sensors due to their high electrochemical activity, good stability, excellent selectivity and high sensitivity. Here, we first summarize the detection principle of SAN-based electrochemical sensors. Then, we review the detection performances of small molecules on SAN-based electrochemical sensors, including H 2 O 2 , dopamine (DA), uric acid (UA), glucose, H 2 S, NO, and O 2. Subsequently, we put forward the optimization strategies to promote the development of SAN-based electrochemical sensors. Finally, the challenges and prospects of SAN-based sensors are proposed. [ABSTRACT FROM AUTHOR]

This review introduces how to optimize the structure of carbon-based diatomic catalysts to promote the electrocatalytic performances of HER, OER, ORR, CO 2 RR and NRR, including adjusting the electronic structure of bimetallic central atoms, regulating the local coordination environment of bimetallic central atoms and tuning the base environment of carbon-based materials. [Display omitted] • We summarize controllable synthesis methods for the fabrication of DACs. • The electronic structure of bimetallic central atoms can be adjusted. • The local coordination environment of bimetallic central atoms can be regulated. • The base environment of carbon-based materials can be tuned. • Several strategies for optimizing electrocatalytic performance are proposed. As an extension of single-atom catalysts (SACs), diatomic catalysts (DACs) perfectly inherit the advantages of SACs but break some theoretical limitations of SACs due to the interaction between dual-atom sites. However, there are still challenges for the electrocatalytic applications of carbon-based DACs, such as difficult in controllable synthesis and identification of bimetallic dimer, hard to adjust the coordination environments of bimetallic sites, poor structural stability, and unclear reaction mechanisms. Here, we summarize controllable synthesis methods for the fabrication of DACs and introduce the characterization techniques in comprehending the geometrical configuration of bimetallic dimer, local electronic structure, coordination environments, and insights into reaction mechanisms by combining in situ characterization and theoretical investigation. Moreover, several important electrocatalytic applications of DACs, including for the hydrogen evolution reaction, oxygen evolution reaction, oxygen reduction reaction, CO 2 reduction reaction, and nitrogen reduction reaction are reviewed. To precipitate the future development of high-performance carbon-based DACs, we put forward several strategies to adjust the electronic structure for optimizing the electrocatalytic performances, including adjusting the electronic structure of bimetallic central atoms, regulating the local coordination environment of bimetallic central atoms, and tuning the base environment. Finally, future research directions of developing advanced carbon-based DACs for electrocatalytic application are proposed. [ABSTRACT FROM AUTHOR]

Abstract: In this work, titanium-doped mesoporous Al2O3 (γ-Ti-Al2O3) was prepared by an evaporation-induced self-assembly method and used as a carrier of Ba/γ-Ti-Al2O3 catalyst to catalyze the aldol condensation of methyl acetate with formaldehyde to methyl acrylate in a fixed-bed reactor. The catalysts were characterized by X-ray diffraction, X-ray photoelectron spectroscopy, N2 adsorption-desorption, pyridine absorption performed via Fourier transform infrared spectroscope (Py-IR), and NH3 and CO2 temperature-programmed desorption (NH3 and CO2-TPD). Experimental results indicated that the doping of the titanium species into the frame work of mesoporous Al2O3 (γ-Ti-Al2O3) had a significant influence on the catalytic activity via modifying the acid-base surface properties of the catalyst. Furthermore, the Ba/γ-Ti-Al2O3 catalyst demonstrated excellent catalytic performance, with a methyl acetate conversion rate of 50% and methyl acrylate selectivity up to 90.2%. Compared with the Ba/Al2O3 catalyst, the Ba/γ-Ti-Al2O3 catalyst had better catalytic activity, stability and potential for practical application, which was likely due to an increased number of Lewis acid sites, especially the medium acid sites.Graphical Abstract: Barium supported mesoporous γ-Ti-Al2O3 catalyst was found to be an effective catalyst for vapor phase aldol condensation of methyl acetate with formaldehyde. [ABSTRACT FROM AUTHOR]

The article discusses the differentiation of gonadal sex between hybrid snakehead of channa argus and channa maculate. According to the author the differentiation is conducted on the basis of genetic and environmental factors and sex control patterns. Also reflects on testicular differentiation and putative testis.