High Charging Voltage Stable and Air Atmosphere Stable Li–O₂ Batteries with an Electrolyte Based on Succinonitrile and In Situ Artificial SEI Construction

One experiment in this study utilized the plasticizer succinonitrile and lithium salt LiTFSI to directly create an ionic liquid electrolyte, with an artificial solid electrolyte interface layer generated using fluoroethylene carbonate. The typical electrolyte exhibited an ionic conductivity of 10–3 S cm–1 at room temperature and an electrochemical window of up to 5.3 V based on electrochemical impedance spectroscopy and linear sweep voltammetry tests. This electrolyte system effectively addresses the issues of decomposition and deterioration of traditional organic electrolytes in Li–O2 batteries at high voltages (over 4.5 V), as well as the problem of direct oxidation of the anode caused by oxygen shuttling, thereby greatly improving the lifespan of Li–O2 batteries. Additionally, the electrolyte’s low volatility and flame retardancy allowed for reliable operation of the battery in an air atmosphere. A Li–O2 battery assembled with the novel electrolyte was capable of cycling in a pure oxygen atmosphere for more than 1000 cycles at a capacity density of 200 mA h g–1 and over 150 cycles at 500 mA h g–1. Even when connected to ambient air without an additional oxygen selective membrane (OSM), the battery can still cycle continuously for more than 350 and 150 cycles at these two kinds of capacity density

High Charging Voltage Stable and Air Atmosphere Stable Li–O₂ Batteries with an Electrolyte Based on Succinonitrile and In Situ Artificial SEI Construction

One experiment in this study utilized the plasticizer succinonitrile and lithium salt LiTFSI to directly create an ionic liquid electrolyte, with an artificial solid electrolyte interface layer generated using fluoroethylene carbonate. The typical electrolyte exhibited an ionic conductivity of 10–3 S cm–1 at room temperature and an electrochemical window of up to 5.3 V based on electrochemical impedance spectroscopy and linear sweep voltammetry tests. This electrolyte system effectively addresses the issues of decomposition and deterioration of traditional organic electrolytes in Li–O2 batteries at high voltages (over 4.5 V), as well as the problem of direct oxidation of the anode caused by oxygen shuttling, thereby greatly improving the lifespan of Li–O2 batteries. Additionally, the electrolyte’s low volatility and flame retardancy allowed for reliable operation of the battery in an air atmosphere. A Li–O2 battery assembled with the novel electrolyte was capable of cycling in a pure oxygen atmosphere for more than 1000 cycles at a capacity density of 200 mA h g–1 and over 150 cycles at 500 mA h g–1. Even when connected to ambient air without an additional oxygen selective membrane (OSM), the battery can still cycle continuously for more than 350 and 150 cycles at these two kinds of capacity density

High Charging Voltage Stable and Air Atmosphere Stable Li–O₂ Batteries with an Electrolyte Based on Succinonitrile and In Situ Artificial SEI Construction

One experiment in this study utilized the plasticizer succinonitrile and lithium salt LiTFSI to directly create an ionic liquid electrolyte, with an artificial solid electrolyte interface layer generated using fluoroethylene carbonate. The typical electrolyte exhibited an ionic conductivity of 10–3 S cm–1 at room temperature and an electrochemical window of up to 5.3 V based on electrochemical impedance spectroscopy and linear sweep voltammetry tests. This electrolyte system effectively addresses the issues of decomposition and deterioration of traditional organic electrolytes in Li–O2 batteries at high voltages (over 4.5 V), as well as the problem of direct oxidation of the anode caused by oxygen shuttling, thereby greatly improving the lifespan of Li–O2 batteries. Additionally, the electrolyte’s low volatility and flame retardancy allowed for reliable operation of the battery in an air atmosphere. A Li–O2 battery assembled with the novel electrolyte was capable of cycling in a pure oxygen atmosphere for more than 1000 cycles at a capacity density of 200 mA h g–1 and over 150 cycles at 500 mA h g–1. Even when connected to ambient air without an additional oxygen selective membrane (OSM), the battery can still cycle continuously for more than 350 and 150 cycles at these two kinds of capacity density

Intrinsic Role of Excess Electrons in Surface Reactions on Rutile TiO₂ (110): Using Water and Oxygen as Probes

Reactions on catalytically active surfaces often involve complex mechanisms with multiple interactions between adsorbates and various subsequently formed intermediates, and a variable number of excess electrons further complicates the involved mechanisms. Experimental techniques face challenges in precisely tuning or determining the number of excess electrons and in elucidating these complex reactions. In this work, the thermodynamic details and reaction pathways of interactions between the most prevalent and important molecular species, H₂O and O₂, on a prototypical rutile TiO₂ (110) surface are investigated using density functional theory calculations on 10 elementary reaction steps with the intention of gaining further insight into surface catalysis. The results suggest that the final product is independent of the reaction pathway when the number of excess electrons is sufficient. The intrinsic role of excess electrons at the reaction level is thus proposed to extend the understanding of the origin, distribution, and transfer of excess electrons. Such an understanding is beneficial to develop high-performance catalysts

Growth of 2D Mesoporous Polyaniline with Controlled Pore Structures on Ultrathin MoS₂ Nanosheets by Block Copolymer Self-Assembly in Solution

The development of versatile strategies toward two-dimensional (2D) porous nanocomposites with tunable pore structures draws immense scientific attention in view of their attractive physiochemical properties and a wide range of promising applications. This paper describes a self-assembly approach for the directed growth of mesoporous polyaniline (PANi) with tunable pore structures and sizes on ultrathin freestanding MoS₂ nanosheets in solution, which produces 2D mesoporous PANi/MoS₂ nanocomposites. The strategy employs spherical and cylindrical micelles, which are formed by the controlled solution self-assembly of block copolymers, as the soft templates for the construction of well-defined spherical and cylindrical mesopores in the 2D PANi/MoS₂ nanocomposites, respectively. With potential applications as supercapacitor electrode materials, the resultant 2D composites show excellent capacitive performance with a maximum capacitance of 500 F g^–1 at a current density of 0.5 A g^–1, good rate performance, as well as outstanding stability for charge–discharge cycling. Moreover, the 2D mesoporous nanocomposites offer an opportunity for the study on the influence of different pore structures on their capacitive performance, which helps to understand the pore structure–property relationship of 2D porous electrode materials and to achieve their electrochemical performance control

LAST: Latent Space-Assisted Adaptive Sampling for Protein Trajectories

Molecular dynamics (MD) simulation is widely used to study protein conformations and dynamics. However, conventional simulation suffers from being trapped in some local energy minima that are hard to escape. Thus, most of the computational time is spent sampling in the already visited regions. This leads to an inefficient sampling process and further hinders the exploration of protein movements in affordable simulation time. The advancement of deep learning provides new opportunities for protein sampling. Variational autoencoders are a class of deep learning models to learn a low-dimensional representation (referred to as the latent space) that can capture the key features of the input data. Based on this characteristic, we proposed a new adaptive sampling method, latent space-assisted adaptive sampling for protein trajectories (LAST), to accelerate the exploration of protein conformational space. This method comprises cycles of (i) variational autoencoder training, (ii) seed structure selection on the latent space, and (iii) conformational sampling through additional MD simulations. The proposed approach is validated through the sampling of four structures of two protein systems: two metastable states of Escherichia coli adenosine kinase (ADK) and two native states of Vivid (VVD). In all four conformations, seed structures were shown to lie on the boundary of conformation distributions. Moreover, large conformational changes were observed in a shorter simulation time when compared with structural dissimilarity sampling (SDS) and conventional MD (cMD) simulations in both systems. In metastable ADK simulations, LAST explored two transition paths toward two stable states, while SDS explored only one and cMD neither. In VVD light state simulations, LAST was three times faster than cMD simulation with a similar conformational space. Overall, LAST is comparable to SDS and is a promising tool in adaptive sampling. The LAST method is publicly available at https://github.com/smu-tao-group/LAST to facilitate related research

Platinum-Modified ZnO/Al₂O₃ for Propane Dehydrogenation: Minimized Platinum Usage and Improved Catalytic Stability

Compared to metallic platinum and chromium oxide, zinc oxide (ZnO) is an inexpensive and low-toxic alternative for the direct dehydrogenation of propane (PDH). However, besides the limited activity, conventional zinc-based catalysts suffer from serious deactivation, because of ZnO reduction and/or carbon deposition. Considering the high cost of platinum, reducing the amount of platinum in the catalyst is always desirable. This paper describes a catalyst comprising ZnO modified by trace platinum supported on Al₂O₃, where the Zn²⁺ species serve as active sites and platinum acts as a promoter. This catalyst contains less platinum than traditional platinum-based catalysts and is much more stable than conventional ZnO catalyst or commercial chromium-based systems during PDH. It is proposed that ZnO was promoted to a stronger Lewis acid by platinum; thus, easier C–H activation and accelerated H₂ desorption were achieved

Sociodemographic and Clinical Characteristics of the Study Sample.

<p>yrs-years; SD-standard deviation; no.-number; BMI-body mass index; Zung SDS-Zung Self Rating Depression Scale; SF-36: Short-Form (36) Health Survey; CFS-Chronic Fatigue Syndrome;</p><p>*- Welch Test;</p>a<p>- one subject in each group used narcotic analgesics;</p>b<p>- anti-hypertensive medications and cholesterol lowering medications;</p>c<p>- vitamins and herbal preparations.</p

Effect of Metformin on Cancer Risk and Treatment Outcome of Prostate Cancer: A Meta-Analysis of Epidemiological Observational Studies

<div><p>Background</p><p>Laboratory studies have shown the anti-tumor effect of metformin on prostate cancer. However, recent epidemiological studies have yielded inconclusive results.</p><p>Methods</p><p>We searched PubMed database from the inception to May 30 2014 for studies which assessed the effect of metformin use on cancer risk of prostate cancer, biochemical recurrence (BCR) and all-cause mortality of patients with prostate cancer. The pooled results and 95% confidence intervals (CIs) were estimated by random-effect model.</p><p>Results</p><p>Twenty-one studies were eligible according to the inclusion criteria. Based on the pooled results of available observational studies, metformin use was significantly associated with a decreased cancer risk (14 datasets, 963991 male subjects, odds ratio: 0.91, 95% CI: 0.85–0.97) and BCR (6 datasets, 2953 patients, hazard ratio: 0.81, 95% CI: 0.68–0.98) of prostate cancer. However, the association of metformin use with all-cause mortality of patients with prostate cancer was not significant (5 datasets, 9241 patients, hazard ratio: 0.86, 95% CI: 0.64–1.14).</p><p>Conclusion</p><p>Results suggest that metformin use appears to be associated with a significant reduction in the cancer risk and BCR of prostate cancer, but not in all-cause mortality of patients with prostate cancer.</p></div