Abstract
A novel coronavirus disease (COVID-19), caused by infection with SARS-CoV-2, has swept across 31 provinces in China and over 40 countries worldwide. The transition from first symptoms to ...acute respiratory distress syndrome (ARDS) is highly likely to be due to uncontrolled cytokine release. There is an urgent need to identify safe and effective drugs for treatment. Chloroquine (CQ) exhibits a promising inhibitory effect. However, the clinical use of CQ can cause severe side effects. We propose that hydroxychloroquine (HCQ), which exhibits an antiviral effect highly similar to that of CQ, could serve as a better therapeutic approach. HCQ is likely to attenuate the severe progression of COVID-19, inhibiting the cytokine storm by suppressing T cell activation. It has a safer clinical profile and is suitable for those who are pregnant. It is cheaper and more readily available in China. We herein strongly urge that clinical trials are performed to assess the preventive effects of HCQ in both disease infection and progression.
Chemical modification of proteins in living cells permits valuable glimpses into the molecular interactions that underpin dynamic cellular events. While genetic engineering methods are often ...preferred, selective labeling of endogenous proteins in a complex intracellular milieu with chemical approaches represents a significant challenge. In this study, we report novel diazocoumarin compounds that can be photoactivated by visible (430–490 nm) and near-infrared light (800 nm) irradiation to photo-uncage reactive carbene intermediates, which could subsequently undergo an insertion reaction with concomitant fluorescence “turned on”. With these new molecules in hand, we have developed a new approach for rapid, selective, and fluorogenic labeling of endogenous protein in living cells. By using CA-II and eDHFR as model proteins, we demonstrated that subcellular localization of proteins can be precisely visualized by live-cell imaging and protein levels can be reliably quantified in multiple cell types using flow cytometry. Dynamic protein regulations such as hypoxia-induced CA-IX accumulation can also be detected. In addition, by two-photon excitation with an 800 nm laser, cell-selective labeling can also be achieved with spatially controlled irradiation. Our method circumvents the cytotoxicity of UV light and obviates the need for introducing external reporters with “click chemistries”. We believe that this approach of fluorescence labeling of endogenous protein by bioorthogonal photoirradiation opens up exciting opportunities for discoveries and mechanistic interrogation in chemical biology.
The ever-growing demand for advanced energy storage devices in portable electronics, electric vehicles and large scale power grids has triggered intensive research efforts over the past decade on ...lithium and sodium batteries. The key to improve their electrochemical performance and enhance the service safety lies in the development of advanced electrode, electrolyte, and auxiliary materials. Ionic liquids (ILs) are liquids consisting entirely of ions near room temperature, and are characterized by many unique properties such as ultralow volatility, high ionic conductivity, good thermal stability, low flammability, a wide electrochemical window, and tunable polarity and basicity/acidity. These properties create the possibilities of designing batteries with excellent safety, high energy/power density and long-term stability, and also provide better ways to synthesize known materials. IL-derived materials, such as poly(ionic liquids), ionogels and IL-tethered nanoparticles, retain most of the characteristics of ILs while being endowed with other favourable features, and thus they have received a great deal of attention as well. This review provides a comprehensive review of the various applications of ILs and derived materials in lithium and sodium batteries including Li/Na-ion, dual-ion, Li/Na-S and Li/Na-air (O
2
) batteries, with a particular emphasis on recent advances in the literature. Their unique characteristics enable them to serve as advanced resources, medium, or ingredient for almost all the components of batteries, including electrodes, liquid electrolytes, solid electrolytes, artificial solid-electrolyte interphases, and current collectors. Some thoughts on the emerging challenges and opportunities are also presented in this review for further development.
A comprehensive review of various applications of ionic liquids and derived materials in lithium and sodium batteries with an emphasis on recent advances.
Hybrid porous nanowire arrays composed of strongly interacting Co3O4 and carbon were prepared by a facile carbonization of the metal–organic framework grown on Cu foil. The resulting material, ...possessing a high surface area of 251 m2 g–1 and a large carbon content of 52.1 wt %, can be directly used as the working electrode for oxygen evolution reaction without employing extra substrates or binders. This novel oxygen evolution electrode can smoothly operate in alkaline solutions (e.g., 0.1 and 1.0 M KOH), affording a low onset potential of 1.47 V (vs reversible hydrogen electrode) and a stable current density of 10.0 mA cm–2 at 1.52 V in 0.1 M KOH solution for at least 30 h, associated with a high Faradaic efficiency of 99.3%. The achieved ultrahigh oxygen evolution activity and strong durability, with superior performance in comparison to the state-of-the-art noble-metal/transition-metal and nonmetal catalysts, originate from the unique nanowire array electrode configuration and in situ carbon incorporation, which lead to the large active surface area, enhanced mass/charge transport capability, easy release of oxygen gas bubbles, and strong structural stability. Furthermore, the hybrid Co3O4-carbon porous nanowire arrays can also efficiently catalyze oxygen reduction reaction, featuring a desirable four-electron pathway for reversible oxygen evolution and reduction, which is potentially useful for rechargeable metal–air batteries, regenerative fuel cells, and other important clean energy devices.
Abstract
Defect engineering is an effective strategy to improve the activity of two-dimensional molybdenum disulfide base planes toward electrocatalytic hydrogen evolution reaction. Here, we report a ...Frenkel-defected monolayer MoS
2
catalyst, in which a fraction of Mo atoms in MoS
2
spontaneously leave their places in the lattice, creating vacancies and becoming interstitials by lodging in nearby locations. Unique charge distributions are introduced in the MoS
2
surface planes, and those interstitial Mo atoms are more conducive to H adsorption, thus greatly promoting the HER activity of monolayer MoS
2
base planes. At the current density of 10 mA cm
−2
, the optimal Frenkel-defected monolayer MoS
2
exhibits a lower overpotential (164 mV) than either pristine monolayer MoS
2
surface plane (358 mV) or Pt-single-atom doped MoS
2
(211 mV). This work provides insights into the structure-property relationship of point-defected MoS
2
and highlights the advantages of Frenkel defects in tuning the catalytic performance of MoS
2
materials.
A solvent‐free induced self‐assembly technology for the synthesis of nitrogen‐doped ordered mesoporous polymers (N‐OMPs) is developed, which is realized by mixing polymer precursors with block ...copolymer templates, curing at 140–180 °C, and calcination to remove the templates. This synthetic strategy represents a significant advancement in the preparation of functional porous polymers through a fast and scalable yet environmentally friendly route, since no solvents or catalysts are used. The synthesized N‐OMPs and their derived catalysts are found to exhibit competitive CO2 capacities (0.67–0.91 mmol g−1 at 25 °C and 0.15 bar), extraordinary CO2/N2 selectivities (98–205 at 25 °C), and excellent activities for catalyzing conversion of CO2 into cyclic carbonate (conversion >95% at 100 °C and 1.2 MPa for 1.5 h). The solvent‐free technology developed in this work can also be extended to the synthesis of N‐OMP/SiO2 nanocomposites, mesoporous SiO2, crystalline mesoporous TiO2, and TiPO, demonstrating its wide applicability in porous material synthesis.
A novel and green strategy in which no solvents are used, for the fast synthesis of nitrogen‐doped ordered mesoporous polymers (N‐OMPs) is developed. The N‐OMPs display competitive CO2 capacities and extraordinary CO2/N2 selectivities, as well as excellent activity for catalytic conversion of CO2. The methodology can also be extended to the synthesis of N‐OMP/SiO2 nanocomposites, mesoporous SiO2, TiO2, and TiPO.
Abstract
Critical barriers to layered Ni-rich cathode commercialisation include their rapid capacity fading and thermal runaway from crystal disintegration and their interfacial instability. ...Structure combines surface modification is the ultimate choice to overcome these. Here, a synchronous gradient Al-doped and LiAlO
2
-coated LiNi
0.9
Co
0.1
O
2
cathode is designed and prepared by using an oxalate-assisted deposition and subsequent thermally driven diffusion method. Theoretical calculations, in situ X-ray diffraction results and finite-element simulation verify that Al
3+
moves to the tetrahedral interstices prior to Ni
2+
that eliminates the Li/Ni disorder and internal structure stress. The Li
+
-conductive LiAlO
2
skin prevents electrolyte penetration of the boundaries and reduces side reactions. These help the Ni-rich cathode maintain a 97.4% cycle performance after 100 cycles, and a rapid charging ability of 127.7 mAh g
−1
at 20 C. A 3.5-Ah pouch cell with the cathode and graphite anode showed more than a 500-long cycle life with only a 5.6% capacity loss.
In nowadays highly competitive and dynamic environment where employees' innovative work behaviour (IWB) has become critical source for business success, employees' quality of work lives is severely ...challenged by the global deregulated labour market. As an institutional effort to combat the challenges faced by labour world, the concept of decent work was proposed by International Labor Organization (ILO) in 1999, which is defined as work—and work‐related contexts—that provides adequate and fair income, social protection, security at workplace, opportunities for personal development and voice and participation in the decisions that affect their lives. This study examines whether realization of decent work promotes IWB. Based on a seven‐dimension construct of decent work, we propose that decent work promotes IWB through enhancing work engagement, with intrinsic motivation and job self‐efficacy partially mediating the positive effect of decent work on work engagement. By means of data with 517 supervisor–employee dyads, we test the hypotheses using structural equations modelling. Our results show good fitness of the hypothesized model, pass for the comparison of alternative models and testing of mediation effects and hence support all the hypotheses. Implications for theories and practices are discussed.
The use of oxide-supported isolated Pt-group metal atoms as catalytic active sites is of interest due to their unique reactivity and efficient metal utilization. However, relationships between the ...structure of these active sites, their dynamic response to environments and catalytic functionality have proved difficult to experimentally establish. Here, sinter-resistant catalysts where Pt was deposited uniformly as isolated atoms in well-defined locations on anatase TiO
nanoparticle supports were used to develop such relationships. Through a combination of in situ atomic-resolution microscopy- and spectroscopy-based characterization supported by first-principles calculations it was demonstrated that isolated Pt species can adopt a range of local coordination environments and oxidation states, which evolve in response to varied environmental conditions. The variation in local coordination showed a strong influence on the chemical reactivity and could be exploited to control the catalytic performance.
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