Modification of pillared MFI zeolite nanosheets by nitridation with tailored activity in benzylation of mesitylene and benzyl alcohol

The modification of pillared MFI zeolites was performed by nitridation of silica pillared MFI zeolite nanosheets under NH3 atmosphere with different time. The resultant zeolites were characterized by a complementary combination of X-ray power diffraction(XRD), scanning electron microscopy(SEM),transmission electron microscopy(TEM), pyridine-IR spectroscopy and N2 adsorption–desorption isotherms. The analyses showed that the nitridation didn’t destroy the crystallinity and specific surface area of zeolites, and the acidity of zeolites can be tailored by tuning the time of nitridation, resulting in the different concentration ratios of Br?nsted-to-Lewis(B/L) acid sites. Moreover, the nitrided zeolites exhibited high selectivity to 2-benzyl-1,3,5-trimethylbenzene than parent silica pillared MFI zeolite nanosheets in benzylation of mesitylene with benzyl alcohol. A balance between Br?nsted acid sites and Lewis acid sites can inhibit the self-etherification of benzyl alcohol and enhance the selectivity of alkylated product. These experimental data implied that nitridation was an effective method to modulate the acidity of zeolites and the synergy between Br?nsted acid sites and Lewis acid sites was a decisive factor to determine the selectivity.

The effect of oxidation of ethane to oxygenates on Pt-and Zn-containing LTA zeolites with tunable selectivity

Platinum and zinc containing LTA zeolite catalysts with tunable meso/microporosity were prepared by using ligand-metal precursors under hydrothermal condition. These materials were employed for oxidation of ethane to oxygenates using hydrogen peroxides as oxidant under mild reaction condition. The results showed that platinum and zinc loaded LTA zeolites were effective for the partial oxidation of ethane with hydrogen peroxide giving the desired C_2 oxygenates. Moreover, the C_1 oxygenates were also obtained through subsequent C–C bond scission pathways. The over oxidation of ethanol/methanol to acetic acid/formic acid could be inhibited through the introduction of mesoporosity in LTA zeolites. Our findings for oxidation of ethane suggested that the selectivity to the oxidation products such as alcohols and acids could be tailored by tuning the metal species within the LTA zeolites and porosity of catalysts, indicating that a balance between the meso/microporosity and metal species in LTA zeolites can be realized for desirable catalysis by one-pot synthesis of zeolites. In addition, the selectivity to oxygenates can also be tuned by control of the reaction conditions, i.e. concentration of hydrogen peroxide or reaction time.

Confined space synthesis of Ni(OH)_(2)-impregnated three-dimensional ordered mesoporous carbon as a high-performance supercapacitor electrode

Regulable loading of Ni(OH)_(2) crystals by using three dimensionally ordered mesoporous carbon(3DOMC)as a support is achieved through a confined growth strategy accompanied by steam-assisted crystallization.Dual forms of high-crystalline nanosheet-like Ni(OH)_(2) severally distribute within mesopores or over the outer surface of 3DOMC particles depending on the loading amount(3%^(−1)5%)of Ni(OH)_(2).Benefitted from the highly hybrid combination and efficient electrolyte diffusion,the obtained Ni(OH)_(2)/carbon nanocomposites exhibit an excellent electrochemical performance,and the optimal sample of 6%_Ni(OH)_(2)/3DOMC with confined extrasmall Ni(OH)_(2) nanosheets as dominant shows the highest specific capacitance of 552.5F.g^(−1) at 1.0A⋅g^(−1),which is 330%higher than the contrast sample by using actived carbon as the support.Furthermore,the assembled hybrid supercapacitor by using 6%_Ni(OH)_(2)/3DOMC and 3DOMC as positive and negative electrodes displays an energy density of 11.7 Wh.kg^(−1) at 288.1 W.kg^(−1) and a superior charge/discharge stability.It is expected that the flexible component,well-defined structure,and superior electrochemical performance could promote a great application potential of Ni(OH)_(2)/3DOMC nanocomposites as supercapacitor electrodes and in other energy storage devices.

Clinical Diagnosis and Treatment Recommendations for Immune Checkpoint Inhibitor-Associated Myocarditis

Immune checkpoint inhibitors(ICIs)are often beneficial in the treatment of multiple types of malignant tumors.However,ICI-associated myocarditis has introduced new clinical challenges.This report highlights the key clinical issues of ICI-associated myocarditis,such as risk factors,diagnosis and differential diagnosis,clinical classification and treatment,monitoring of outcomes,and restart of treatment.Additionally,practical guidance and suggestions for the diagnosis and treatment of ICI-associated myocarditis are proposed with reference to the relevant consensuses or guidelines and newly published evidence-based studies in China and other countries in combination with clinical experience of physicians from Shanghai,China.