Efficient Electrocatalytic Reduction of CO2 by Nitrogen-Doped Nanoporous Carbon/Carbon Nanotube Membranes: A Step Towards the Electrochemical CO2 Refinery

Herein we introduce a straightforward, low cost, scalable, and technologically relevant method to manufacture an all-carbon, electroactive, nitrogen-doped nanoporous-carbon/carbon-nanotube composite membrane, dubbed “HNCM/CNT”. The membrane is demonstrated to function as a binder-free, high-performance gas diffusion electrode for the electrocatalytic reduction of CO₂ to formate. The Faradaic efficiency (FE) for the production of formate is 81 %. Furthermore, the robust structural and electrochemical properties of the membrane endow it with excellent long-term stability.     

Studies on PNPP Hydrolysis Catalyzed by Divalent Metal Ion Macrocyclic Schiff Base Complexes in Micellar Solution

Two transitional metal ion macrocyclic Schiff base complexes, NiL and CuL were synthesized and characterized, and the metallomicelles made up of the nickel(II) and copper(II) complexes and surfactants(LSS, Brij35, CTAB), as mimic hydrolytic metalloenzyme, were used in catalytic hydrolysis of carboxylic ester (PNPP). The analysis of specific absorption spectrums of the hydrolytic reaction systems indicates that key intermediates, made up of PNPP and Ni(II) or Cu(II) complexes, have formed in the reaction processes of the PNPP catalytic hydrolysis. In this, based on the analytic result of specific absorption spectrum, the mechanism of PNPP catalytic hydrolysis has been proposed; a kinetic mathematical model, applied to the calculation of the kinetic parameter of PNPP catalytic hydrolysis has been established on the foundation of the mechanism proposed; the acid effect of reaction system, structure effect of the complexes, effect of temperature and effects of micelle on the rate of PNPP hydrolysis catalyzed by the complexes also have been discussed.     

Hydrothermal Synthesis and Primary Gas Sensing Properties of CuO Nanosheets

Uniformity nanosheets of CuO were prepared by a mild hydrothermal synthesis method. Phase analysis was carried out using x-ray diffraction (XRD) and the result confirmed the CuO nanosheets as a single phase. The field-emission scanning electron microscopy (FE-SEM) was used to observe the morphology of CuO nanosheets while the gas sensing properties of these unique CuO nanosheets were tested at a static state system. The results show that the CuO has uniformity nanosheets, and the gas sensing property show that the CuO nanosheets gas sensor has a stable gas response and the same gas sensitivity trend to tested gases. This method may be suitable for larger-scale production of these CuO nanosheets for practical applications.     

Radical cation salt induced Povarov reaction between iminoethyl glyoxylate and N-vinylamides: synthesis of quinoline-2-carboxylate derivatives

A domino process between iminoethyl glyoxylate and N-vinylamides was achieved under the catalytic radical cation salt induced conditions, producing a series of quinoline-2-carboxylates. N-Vinylamides were involved as an acetylene equivalent. A possible mechanism was proposed to rationalize the formation of the products.     

New Sesquiterpenes from the Flowers of Chrysanthemum indicum L.

Two new guaianolides (=guaianolactones), chrysanthguaianolactone A and B ( 1 and 2 , resp.), and one new eudesmane sesquiterpene, chrysanthemdiol A ( 6 ), together with seven known sesquiterpenes were isolated from the flowers of Chrysanthemum indicum L. Their structures were elucidated on the basis of spectroscopic evidence.     

An experimental investigation of one- and two-degree of freedom VIV of cylinders

In the paper,an experiment investigation was conducted for one-and two-degree of freedom vortex-induced vibration(VIV) of a horizontally-oriented cylinder with diameter of 11 cm and length of 120 cm.In the experiment,the spring constants in the cross-flow and in-line flow directions were regulated to change the natural vibration frequency of the model system.It was found that,in the one-degree of freedom VIV experiment,a "double peak" phenomenon was observed in its amplitude within the range of the reduced velocities tested,moreover,a "2T" wake appeared in the vicinity of the second peak.In the two-degree of freedom VIV experiment,the trajectory of cylinder exhibited a reverse "C" shape,i.e.,a "new moon" shape.Through analysis of these data,it appears that,besides the non-dimensional in-line and cross-flow natural vibration frequency ratios,the absolute value of the natural vibration frequency of cylinder is also one of the important parameters affecting its VIV behavior.