Unraveling the Selectivity and Synergistic Mechanism of Cu-Based Alloys for CO2 Reduction.

Understanding the synergistic effect of Cu-based alloys on the adsorption behavior and selectivity of the CO2 reduction reaction is a crucial step toward directional catalyst design. To this end, density functional theory calculations are employed to investigate Cu-based alloys with diverse doping elements and contents. The results show that the scaling relation still holds in the alloy system, and the strategies to improve the selectivity are put forward based on the adsorption strength of *C and *OCHO intermediates. Further, a model combining the adsorption theory and machine learning algorithm is proposed to capture the relationship between the adsorption energy and the geometric environment. It explains that the difference in d-band centers between the doped metals and Cu affects the variation trend of the adsorption strength and reveals that the intermetallic synergistic effect can be quantified by the bonding distance and d orbital radius on both the adsorbate and metal side.

Highly efficient removal of strontium from contaminated wastewater by a porous zirconium phosphate material.

Effective and efficient disposal of radioactive pollution has been crucial for responding to unexpected nuclear accidents and guaranteeing the sustainable development of nuclear energy. In this study, a kind of porous zirconium phosphate was synthesized with a sol-gel process followed by a post-synthesis modification to remove the radioactive Sr2+ from wastewater. The prepared materials were characterized by different technologies including FT-IR, SEM-EDS, XRD and XPS, and then the adsorption performance was evaluated in batch and column modes. Experimental results suggested that the porous zirconium phosphate adsorbent was successfully prepared with Na+ dispersed in the channels for exchange. It inherited the excellent properties of zirconium dioxide aerogel and exhibited mesoporous structure and large specific surface area. Compared with traditional zirconium phosphate, the adsorption kinetics and the adsorption capacity were improved simultaneously. Especially, it showed excellent selectivity towards Sr2+ among different cations, and even could remove the low-level Sr2+ from natural seawater efficiently, which powerfully demonstrated that the prepared material could be applied in the treatment of practical wastewater. Spectra studies uncovered that the adsorption activities were dominated by the ion exchange mechanism between external Sr2+ and interlaminar Na+ or H+. In conclusion, this paper not only reports a novel synthesis strategy for the acquisition of porous zirconium phosphate, but also presents a promising adsorbent for the Sr2+ removal.

Revealing the Nature of C-C Coupling Sites on a Cu Surface for CO2 Reduction.

Electrochemical CO2 reduction technology plays an important role in reducing CO2 into valuable chemical fuels. Therein, Cu-based catalysts show superior performance for producing high-value C2+ products. Here, we illustrate the ascendency of high-index facets of Cu catalysts in producing C2+ products and find that two kinds of sites favor C-C coupling on the surface. One is prone to adsorb the C-C coupling structure by spanning stepped coppers with different coordination numbers. The other is to embed the structure along two columns of Cu with similar characteristics through O and C adsorbed simultaneously. Within all research surfaces, the coupling energy barrier is lowest on the Cu(911) facet, which is consistent with the experiment. The less charged sites promote the stabilization of the CO-CO structure as determined by charge analysis. Furthermore, our results suggest that the high selectivity for C2+ products on a Cu surface could significantly come from the contribution of the high-index facet.

A Closed-Loop Neuromodulation Chipset With 2-Level Classification Achieving 1.5-Vpp CM Interference Tolerance, 35-dB Stimulation Artifact Rejection in 0.5ms and 97.8%-Sensitivity Seizure Detection.

This work presents an 8-channel closed-loop neuromodulation chipset with 2-level seizure classification. The power-consuming fine classifier is only enabled when the coarse classifier in the frontend chip judges the patient's status as "suspected seizure". This scheme can reduce the overall power consumption extensively since seizure usually occurs with very low possibility. In the capacitive-coupled instrument amplifier (CCIA) of the front-end IC, a feedback based common-mode (CM) cancellation circuit is proposed to suppress large-scale CM interferences and the stimulation artifacts are suppressed by a mixed-signal loop with fast response. An auto-zero based pre- charge path is adopted to boost the input impedance, while the electrode DC offset is canceled by a DC servo loop with very-large and accurate time constant. The 2.32-mm2 front-end chip and 3.51-mm2 DSP chip implemented in 0.18 µm CMOS are applied in a deep-brain stimulation (DBS) neuromodulator. Measurement results show that the CCIA can suppress 1.5-Vpp CM interference, and achieve an accurate high-pass corner frequency as low as 0.1 Hz and an input impedance greater than 2.2 GΩ. The overall classifier achieves 97.8% sensitivity and consumes only 1.16-µW average power for the CHB-MIT database test. The chipset has been verified by in vivo measurement, showing that the stimulation artifact can be suppressed by 35 dB within 0.5 ms.

Environmental exposure to 17ß-trenbolone during adolescence inhibits social interaction in male mice.

Puberty is a critical period for growth and development. This period is sensitive to external stimuli, which ultimately affects the development of nerves and the formation of social behaviour. 17ß-Trenbolone (17ß-TBOH) is an endocrine disrupting chemicals (EDCs), which had been widely reported in aquatic vertebrates. But there is little known about the effects of 17ß-TBOH on mammals, especially on adolescent neurodevelopment. In this study, we found that 17ß-TBOH acute 1 h exposure can cause the activation of the dopamine circuit in pubertal male balb/c mice. At present, there is little known about the effects of puberty exposure of endocrine disruptors on these neurons/nerve pathways. Through a series of behavioural tests, exposure to 80 µgkg-1 d-1 of 17ß-TBOH during adolescence increased the anxiety-like behaviour of mice and reduced the control of wheel-running behaviour and the response of social interaction behaviour. The results of TH immunofluorescence staining showed that exposure to 17ß-TBOH reduced dopamine axon growth in the medial prefrontal cortex (mPFC). In addition, the results of real-time PCR showed that exposure to 17ß-TBOH not only down-regulated the expression of dopamine axon development genes, but also affected the balance of excitatory/inhibitory signals in mPFC. In this research, we reveal the effects of 17ß-TBOH exposure during adolescence on mammalian behaviour and neurodevelopment, and provide a reference for studying the origin of adolescent diseases.

Effects of 17ß-trenbolone exposure on sex hormone synthesis and social behaviours in adolescent mice.

17ß-Trenbolone (17ß-TBOH) is an endocrine disruptor that has been widely reported in aquatic organisms. However, little is known about the effect of 17ß-TBOH on mammals, particularly on the development of adolescents. Through a series of behavioural experiments, exposure to at 80 µg kg -1 d -1 and 800 µg kg -1 d -1 17ß-TBOH during puberty (from PND 28 to 56, male mice) increased anxiety-like behaviours. Exposure to the low dose of 80 µg kg -1 d -1 resulted in a clear social avoidance behaviour in mice. The two doses affected testicular development and endogenous androgen synthesis in male mice. In addition, 17ß-TBOH exposure altered the differentiation of oligodendrocytes and the formation of the myelin sheath in the medial prefrontal cortex (mPFC). These results reveal the effects of 17ß-TBOH on the behaviours, gonadal and neurodevelopment of adolescent mammals. In addition, the inhibition of the secretion of endogenous hormones and decrease in the formation of the myelin sheath in mPFC may be associated with the 17ß-TBOH-induced behavioural changes in mice.