It is highly attractive to construct cost-effective hybrid electrocatalysts with superior activity for the hydrogen evolution reaction (HER) in acids. In this communication, we report a novel structure consisting of a CuP-CoP hybrid nanowire array supported on carbon cloth (CuP-CoP/CC) as a superior HER electrocatalyst in acidic media. Owing to the synergistic effect between CuP and CoP, this CuP-CoP/CC catalyst exhibits superior catalytic HER performance, needing an overpotential of 59 mV to drive a current density of 10 mA cm in 0.5 M HSO, 24 and 130 mV less than that for CoP/CC and CuP/CC, respectively. Moreover, this catalyst also shows high long-term electrochemical durability.

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A series of Cu−Ni/CeO 2 -nanotube catalysts is prepared by an impregnation method for CO 2 hydrogenation to CH 3 OH. Regular CeO 2 nanotubes are perfectly formed with a tube diameter of about 30−50 nm and Cu−Ni alloy is well dispersed on CeO 2 nanotube without nanotube morphology change. There is a synergistic effect between Ni and Cu, promoting the bimetallic Cu−Ni dispersion, reducibility, CO adsorption and hydrogenation. Additionally, a strong interaction is observed between Cu−Ni alloy and CeO 2 , and it contributes to partial reduction of Ce 4+ to Ce 3+ and formation of oxygen vacancies which adsorb and activate CO 2 . It is shown that both CO 2 conversion and CH 3 OH space-time yield increase at first, reach their maximum values at a Ni/ (Cu+Ni) ratio of 2/3, and then decrease with increasing the Ni/(Cu+Ni) ratio. The CeO 2 -nanotube supported CuNi 2 catalyst gives CO 2 conversion of 17.8% and CH 3 OH space-time yield of 18.1 mmol/(g cat •h) after preliminary optimization. Furthermore, it exhibits an excellent catalytic performance within a wide range of space velocity.

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This prospective cross-sectional study aimed to evaluate the agreement of two new biometers for measuring ocular biometric parameters in young healthy eyes. ocular biometric parameters were measured using IOLMaster 700 and OA-2000. Power vector analyses of Cartesian (J0) and oblique (J45) components of corneal astigmatism were performed. The right eyes of 103 healthy volunteers were analyzed. The 95% limits of agreement ranged from −0.03 to 0.03 mm, −0.08 to 0.07 mm, −0.18 to 0.18 diopters (D), −1.09 to 1.16 D, −1.18 to 1.15 D for axial length (AL), anterior chamber depth (ACD), mean keratometry, J0 and J45 respectively, which were all comparable between the two biometers, while significant differences were detected in lens thickness (LT), central corneal thickness (CCT), whiteto-white (WTW) and pupil diameter (PD). Predicted intraocular lens (IOL) powers were comparable between the two biometers by Haigis and Barrett Universal II formulas, while not by SRK/T, Hoffer Q and Holladay 2. Excepting CCT, WTW and PD meaurements, IOLMaster 700 and OA-2000 have excellent agreement on ocular biometric measurements and astigmatism power vectors, which provides more options for ocular biometric measurements and enables constant optimization for IOL power calculation.