0D/2D heterojunctions, especially quantum dots (QDs)/nanosheets (NSs) have attracted significant attention for use of photoexcited electrons/holes due to their high charge mobility. Herein, ...unprecedent heterojunctions of vanadate (AgVO3, BiVO4, InVO4 and CuV2O6) QDs/graphitic carbon nitride (g‐C3N4) NSs exhibiting multiple unique advances beyond traditional 0D/2D composites have been developed. The photoactive contribution, up‐conversion absorption, and nitrogen coordinating sites of g‐C3N4 NSs, highly dispersed vanadate nanocrystals, as well as the strong coupling and band alignment between them lead to superior visible‐light‐driven photoelectrochemical (PEC) and photocatalytic performance, competing with the best reported photocatalysts. This work is expected to provide a new concept to construct multifunctional 0D/2D nanocomposites for a large variety of opto‐electronic applications, not limited in photocatalysis.
Vanadate quantum dots including AgVO3, BiVO4, InVO4, and CuV2O6 were strongly coupled with graphitic carbon nitride nanosheets using an in situ growth strategy. These quantum dots displayed a much better visible‐light‐driven photoelectrochemical activity and photocatalytic degradation efficiency than single vanadate quantum dots, carbon nitride nanosheets or previously reported highly active photocatalysts.
Human infection with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) causes coronavirus disease 2019 (COVID-19) and there is no cure currently. The 3CL protease (3CLpro) is a highly ...conserved protease which is indispensable for CoVs replication, and is a promising target for development of broad-spectrum antiviral drugs. In this study we investigated the anti-SARS-CoV-2 potential of Shuanghuanglian preparation, a Chinese traditional patent medicine with a long history for treating respiratory tract infection in China. We showed that either the oral liquid of Shuanghuanglian, the lyophilized powder of Shuanghuanglian for injection or their bioactive components dose-dependently inhibited SARS-CoV-2 3CLpro as well as the replication of SARS-CoV-2 in Vero E6 cells. Baicalin and baicalein, two ingredients of Shuanghuanglian, were characterized as the first noncovalent, nonpeptidomimetic inhibitors of SARS-CoV-2 3CLpro and exhibited potent antiviral activities in a cell-based system. Remarkably, the binding mode of baicalein with SARS-CoV-2 3CLpro determined by X-ray protein crystallography was distinctly different from those of known 3CLpro inhibitors. Baicalein was productively ensconced in the core of the substrate-binding pocket by interacting with two catalytic residues, the crucial S1/S2 subsites and the oxyanion loop, acting as a "shield" in front of the catalytic dyad to effectively prevent substrate access to the catalytic dyad within the active site. Overall, this study provides an example for exploring the in vitro potency of Chinese traditional patent medicines and effectively identifying bioactive ingredients toward a specific target, and gains evidence supporting the in vivo studies of Shuanghuanglian oral liquid as well as two natural products for COVID-19 treatment.
In this letter, a compact high-isolated multiple-input-multiple-output (MIMO) antenna module based on a chip capacitive decoupler is proposed for the fifth-generation (5G) smartphones. The antenna ...module consists of two feeding ports, radiating metal strips, and a chip capacitive decoupler within a compact size of 16 × 6 mm 2 . In this design, two L-shaped metal strips are used as distributed capacitors to compress the size of the module. Meanwhile, a chip capacitive decoupler is added to improve isolation between the two feeding ports, which is realized with an analysis of common and differential modes. In addition, spiral slots are used to adjust the isolation between the modules. A prototype MIMO antenna with four such dual-port antenna modules was tested in the 3.5 GHz band. The measured -6 dB bandwidths of the two ports are 310 MHz (3.42-3.73 GHz) and 360 MHz (3.33-3.69 GHz), respectively, and the isolation is 24 dB at 3.5 GHz. The measured efficiencies are 60.5% and 52.7% at 3.5 GHz. The compact MIMO antenna module with high-isolation property provides a hopeful solution for the 5G mobile terminals.
This paper proposes an effective sizing strategy for distributed battery energy storage system (BESS) in the distribution networks under high photovoltaic (PV) penetration level. The main objective ...of the proposed method is to optimize the size of the distributed BESS and derive the cost-benefit analysis when the distributed BESS is applied for voltage regulation and peak load shaving. In particular, a system model that includes a physical battery model and a voltage regulation and peak load shaving oriented energy management system (EMS) is developed to apply the proposed strategy. The cost-benefit analysis presented in this paper considers factors of BESS influence on the work stress of voltage regulation devices, load shifting and peaking power generation, as well as individual BESS cost with its lifetime estimation. Based on the cost-benefit analysis, the cost-benefit size can be determined for the distributed BESS.
Chitosan modification is an important method for the development of adsorbents that has attracted considerable interest in recent years. In this regard, a new type of efficient Pb(II) adsorbent was ...prepared in a simple and cost-effective way. In this study, carboxylated chitosan (CYCS) and carboxylated nanocellulose (CNC) were used to chelate and synthesize hydrogel spheres with effective adsorption sites, in calcium chloride solution. The prepared carboxylated chitosan/carboxylated nanocellulose (CYCS/CNC) hydrogel beads were used as Pb(II) adsorbents, and using scanning electron microscopy, Fourier transform infrared spectroscopy, and X-ray photoelectron spectroscopy, the structure and adsorption properties of the prepared beads were investigated. The CYCS/CNC adsorbents exhibited an excellent aqueous Pb(II) adsorption capacity (qm = 334.92 mg g−1), and the experimental results further revealed that the adsorption data fitted well with the Langmuir model, and the adsorption kinetics accorded with the pseudo-second-order model. Additionally, the adsorption mechanism was identified as monolayer chemisorption.
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•Efficient and economic CYCS/CNC composite is prepared for Pb(II) adsorption.•CYCS/CNC exhibits excellent aqueous Pb(II) adsorption capacity (Qm = 334.92 mg g−1).•Adsorption mechanism of CYCS/CNC includes chemical and electrostatic adsorption.•The adsorption performance is good even after four regeneration cycles.
Photoredox‐based C−H bond functionalization constitutes one of the most powerful and atom‐economical approaches to organic syntheses. During this type of reaction, single electron transfer takes ...place between the photocatalyst (PC) and redox‐ active substrates. Electrosynthesis also involves electron transfer between substrates and electrodes. In this paper, we focus upon electrochemical cross‐coupling of C(sp2)−H with aryldiazonium salts and have developed an efficient electrochemical approach to the Minisci‐type arylation reaction. The constant current paired electrosynthesis proceeds in a simple undivided cell without external supporting electrolyte, features a wide range of substrates and is easy to scale‐up. These results demonstrate that photoredox‐based cross‐coupling of C(sp2)−H with aryldiazonium salts can also proceed successfully under paired electrolysis conditions, thereby contributing to understanding of the parallels between photosynthesis and electrosynthesis.
Understanding photoinduced charge transfer from nanomaterials is essential to the many applications of these materials. This review summarizes recent progress in understanding charge transfer from ...quantum dots (QDs), an ideal model system for investigating fundamental charge transfer properties of low-dimensional quantum-confined nanomaterials. We first discuss charge transfer from QDs to weakly coupled acceptors within the framework of Marcus nonadiabatic electron transfer (ET) theory, focusing on the dependence of ET rates on reorganization energy, electronic coupling, and driving force. Because of the strong electron-hole interaction, we show that ET from QDs should be described by the Auger-assisted ET model, which is significantly different from ET between molecules or from bulk semiconductor electrodes. For strongly quantum-confined QDs on semiconductor surfaces, the coupling can fall within the strong coupling limit, in which case the donor-acceptor interaction and ET properties can be described by the Newns-Anderson model of chemisorption. We also briefly discuss recent progress in controlling charge transfer properties in quantum-confined nanoheterostructures through wavefunction engineering and multiple exciton dissociation. Finally, we identify a few key areas for further research.
As a typical metal–organic framework material, UiO-66 has good potential for removing pharmaceuticals and personal care products from water. However, the application of this powdery adsorbent has ...been limited by the difficult recovery from the liquid. To overcome this weakness, we prepared composite beads constituted by sodium alginate and UiO-66 by solidification in CaCl
2
solution. The material was characterized by SEM, FTIR, XRD, BET, and TGA methods. These composite beads were applied to remove a common antibiotic Levofloxacin (LOFX) from water, and the experimental parameters (i.e., initial LOFX concentration, adsorption time, pH, and adsorbent dose) were optimized. The adsorption data could be satisfactorily fitted to the Langmuir isotherm model (
R
2
= 0.9871) and the pseudo-second-order kinetic model (
R
2
= 0.9990). The regeneration experiment of the composite beads revealed that the adsorption efficiency of levofloxacin was higher than 70% even after 5 cycles.
Scheme 1 Synthesis route of UiO-66/CA
Battery storage controlled by an energy management system (EMS) becomes an enabling technique to enhance solar farm integration. In this paper, the EMS controls battery storage to shape the ...fluctuated photovoltaic (PV) plant output into a relatively constant power and support the peak load. The proposed integrated design method considers both battery size and EMS impacts on the utility benefits and cost. The utility benefits include power generation, peak power support, and reduced line losses. The cost of battery storage is determined by the size and lifetime based on the developed battery models. Accordingly, the utility revenue change due to the battery storage controlled by EMS can be evaluated. Therefore, the integrated design of battery size and EMS can be determined by managing the change of utility revenue to gain economic benefits for the large-scale PV power plant application. Finally, the lithium-ion phosphate (LiFePO 4 ) battery and lead-acid battery are compared to demonstrate the proposed method on a utility system model, respectively.
Lactate is closely related to various cellular processes, such as angiogenesis, responses to hypoxia, and macrophage polarization, while regulating natural immune signaling pathways and promoting ...neurogenesis and cognitive function. Lysine lactylation (Kla) is a novel posttranslational modification, the examination of which may lead to new understanding of the nonmetabolic functions of lactate and the various physiological and pathological processes in which lactate is involved, such as infection, tumorigenesis and tumor development. Using liquid chromatography–tandem mass spectrometry (LC‒MS/MS), researchers have identified lactylation in human gastric cancer cells and some other species, but no research on lactylation in human lungs has been reported. In this study, we performed global profiling of lactylation in human lungs under normal physiological conditions, and 724 Kla sites in 451 proteins were identified. After comparing the identified proteins with those reported in human lactylation datasets, 141 proteins that undergo lactylation were identified for the first time in this study. Our work expands the database on human lactylation and helps advance the study on lactylation function and regulation under physiological and pathological conditions.