Cu-based catalysts have attracted much interest in CO 2 hydrogenation to methanol because of their high activity. However, the effect of interface, coordination structure, particle size and other underlying factors existed in heterogeneous catalysts render to complex active sites on its surface, therefore it is di cult to study the real active sites for methanol synthesis. Here, we report a novel Cu-based catalyst with isolated Cu active sites (Cu 1 -O 3 units) for highly selective hydrogenating CO 2 to methanol at low temperature (100% selectivity for methanol at 180 o C). Experimental and theoretical results reveal that the single-atom Cu-Zr catalyst with Cu 1 -O 3 units is only contributed to synthesize methanol at 180 o C, but the Cu clusters or nanoparticles with Cu-Cu or Cu-O-Cu active sites will promote the process of reverse water gas shift (RWGS) side reaction to form undesirable byproducts CO. Furthermore, the Cu 1 -O 3 units with tetrahedral structure could gradually migrate to the catalyst surface for accelerating CO 2 hydrogenation reaction during catalytic process. The high activity isolated Cu-based catalyst with legible structure will be helpful to understand the real active sites of Cu-based catalysts for methanol synthesis from CO 2 hydrogenation, thereby guiding further design the Cu catalyst with high performance to meet the industrial demand, at the same time as extending the horizontal of single atom catalyst for application in the thermal catalytic process of CO 2 hydrogenation.

Study design: An animal model of transected spinal cord injury (SCI) was used to test the hypothesis that cografted neural stem cells (NSCs) and NT-3-SCs promote morphologic and functional recoveries of injured spinal cord. Objective: To explore whether cotransplant of NSCs and NT-3-SCs could promote the injured spinal cord repair. Setting: Zhongshan Medical College, Sun Yat-sen University, PR China. Methods: Female Sprague-Dawley (SD) rats weighing on 200-220 g were used to prepare SCI models. The spinal cord was transected between T 9 and T 10 , then NSCs, SCs þ NSCs, LacZSCs þ NSCs, or NT-3-SCs þ NSCs were grafted into the transected site. Results: (1) Part of NSCs could differentiate to neuron-like cells in the transected site and the percentage of differentiation was NT-3-SCs þ NSCs group4SCs þ NSCs group4NSCs group. (2) In the grafted groups, there were 5-HT, CGRP, and SP positive nerve fibres within the transected site. Some fluorogold (FG)-labeled cells were found in the spinal cord rostral to the transected site, the red nuclei and the inner pyramidal layer of sensorimotor cortex. (3) The cells grafted could enhance the injured neurons survival in inner pyramidal layer of sensorimotor cortex, red nuclei of midbrain, and Clark's nuclei of spinal cord's L1 segment, could decrease the latency and increase the amplitude of cortical somatosensory evoked potential (CSEP) and cortical motor evoked potential (CMEP), and could promote partly structural and functional recovery of the SCI rats.Conclusion: These results demonstrate that cografted NT-3-SCs and NSCs is a potential therapy for SCI.

A novel TS-1 (TS-1S) catalyst with newly-generated defects, i.e. Ti(OSi)3OH species, which exhibits the highest reactivity among different Ti species, is constructed in an ingenious strategy. This also provides a promising way to effectively tune the intrinsic nature of Ti active centres in other titanosilicates.

A facile strategy is proposed to construct a highly active oxidation catalyst with optimally distributed titanium coordination states containing "TiO4" and "TiO6" species. The "TiO6" species in TS-1(+) shows a superior catalytic oxidation activity, which is 2-3 times that of "TiO4" species in TS-1.