Since China is facing a complicated international situation and sustainable development requirement at the same time, this paper examines the effects of external uncertainty, international sanctions, ...on green innovations by adopting the system generalized method of moments (GMM) estimation for 30 provinces (autonomous region and municipalities) from 1997 to 2019. We employ green inventions as the dependent variable and 5 indicators of sanctions (including unilateral, plurilateral, multilateral, economic, and intensity) as the main explanatory variables alternately. For further robustness tests, we use substitution variable green utility models, adopt sub-samples in different regions, change the empirical methodology, and add omitted variables. We also examine the mechanism effects of three possible channels. The conclusion is that plurilateral and economic sanctions both present significant negative impacts on green innovations, whereas China was not affected by unilateral or multilateral sanctions during the sample period. GDP, interpersonal globalization, and environment are proved to be the possible channels through which sanctions affect green innovations. Our research findings should assist Chinese-listed companies suffering from sanctions to make better responses on their way to green innovations.
The nexus between extreme events and energy price risk is of great importance in energy finance analysis due to the fact that those events generally exert strong impacts on energy financial risk. For ...a better estimation of the influence of extreme events on energy price risk, this research employs long span daily data from April 1, 1983 to December 30, 2019 and find first that both natural and human extreme events significantly increase oil price risk. Second, among all natural disasters, we find that the negative impact of an epidemic on oil price risk is the greatest. After replacing the measurement indicators of extreme events, re-estimating the models for two subsamples, using different data frequencies of weekly data and monthly data and using SVAR model to further analyze the relationship between extreme events and oil price risk, the above conclusions are still robust. Third, we also used natural gas price risk as a substitute variable for energy price risk, and found that the occurrence of natural disasters increases natural gas price risk, but terrorism has no significant impact on it.
•This paper investigates the relation between extreme events and energy price risk.•Using long span daily data from April 1, 1983 to December 30, 2019.•The results show that both natural and human extreme events significantly increase oil price risk.•Among all natural disasters, the negative impact of an epidemic on oil price risk is the greatest.
Rechargeable zinc–air batteries constitute promising next‐generation energy storage devices due to their intrinsic safety, low cost, and feasibility to realize high cycling current density and long ...cycling lifespan. Nevertheless, their cathodic reactions involving oxygen reduction and oxygen evolution are highly sluggish in kinetics, requiring high‐performance noble‐metal‐free bifunctional electrocatalysts that exceed the current noble‐metal‐based benchmarks. Herein, a noble‐metal‐free bifunctional electrocatalyst is fabricated, which demonstrates ultrahigh bifunctional activity and renders excellent performance in rechargeable zinc–air batteries. Concretely, atomic Co–N–C and NiFe layered double hydroxides (LDHs) are respectively selected as oxygen reduction and evolution active sites and are further rationally integrated to afford the resultant CoNC@LDH composite electrocatalyst. The CoNC@LDH electrocatalyst exhibits remarkable bifunctional activity delivering an indicator ΔE of 0.63 V, far exceeding the noble‐metal‐based Pt/C+Ir/C benchmark (ΔE = 0.77 V) and most reported electrocatalysts. Correspondingly, ultralong lifespan (over 3600 cycles at 10 mA cm−2) and excellent rate performances (cycling current density at 100 mA cm−2) are achieved in rechargeable zinc–air batteries. This work highlights the current advances of bifunctional oxygen electrocatalysis and endows high‐rate and long‐cycling rechargeable zinc–air batteries for efficient sustainable energy storage.
Ultrahigh bifunctional electrocatalytic activity for oxygen reduction and evolution is achieved with the indicator ΔE = 0.63 V, far exceeding the noble‐metal‐based benchmark and most reported electrocatalysts. Corresponding rechargeable zinc–air batteries afford ultralong lifespan over 3600 cycles at 10 mA cm−2 and ultrahigh cycling current density of 100 mA cm−2.
Countries around the world are facing enormous challenges in their economic and social development as COVID‐19 continues to spread, resulting in slower economic recovery in the post‐pandemic era. ...Considering the impact of economic growth on future sustainable development in this new era, green economic recovery (GER) can achieve a win‐win situation between economic recovery and environmental improvement and bring forth environmentally sustainable economic growth. This research first lists related COVID‐19 literature surveys and GER policies in the post‐pandemic era in China. Based on a comparative study of the international experience of GER policy practices, this paper then analyzes the opportunities and challenges China faces for GER and puts forward countermeasures and suggestions on how to promote its sustainable development in the post‐epidemic era. We believe our research presents useful enlightenments for sustainable economic and social development in the post‐epidemic era.
Regulating the fluorescent properties of organic small molecules in a controlled and dynamic manner has been a fundamental research goal. Although several strategies have been exploited, realizing ...multi-color molecular emission from a single fluorophore remains challenging. Herein, we demonstrate an emissive system by combining pyrene fluorophore and acylhydrazone units, which can generate multi-color switchable fluorescent emissions at different assembled states. Two kinds of supramolecular tools, amphiphilic self-assembly and γ-cyclodextrin mediated host-guest recognition, are used to manipulate the intermolecular aromatic stacking distances, resulting in the tunable fluorescent emission ranging from blue to yellow, including a pure white-light emission. Moreover, an external chemical signal, amylase, is introduced to control the assembly states of the system on a time scale, generating a distinct dynamic emission system. The dynamic properties of this multi-color fluorescent system can be also enabled in a hydrogel network, exhibiting a promising potential for intelligent fluorescent materials.
High‐performance bifunctional oxygen electrocatalysis constitutes the key technique for the widespread application of clean and sustainable energy through electrochemical devices such as rechargeable ...Zn–air batteries. Single‐atom electrocatalysts with maximum atom efficiency are highly considered as an alternative of the present noble‐metal‐based electrocatalysts. However, the fabrication of transition metal single‐atoms is very challenging, requiring extensive attempts of precursors with novel design principles. Herein, an all‐covalently constructed cobalt‐coordinated framework porphyrin with graphene hybridization is innovatively designed and prepared as the pyrolysis precursor to fabricate single‐atom Co–Nx–C electrocatalysts. Excellent electrochemical performances are realized for both bifunctional oxygen electrocatalysis and rechargeable Zn–air batteries with regard to reduced overpotentials, improved kinetics, and prolonged cycling stability comparable with noble‐metal‐based electrocatalysts. Design principles from multiple scales are proposed and rationalized with detailed mechanism investigation. This work not only provides a novel precursor for the fabrication of high‐performance single‐atom electrocatalysts, but also inspires further attempts to develop advanced materials and emerging applications.
Cobalt‐coordinated framework porphyrin hybridized with graphene is employed as the pyrolysis precursor to fabricate single‐atom Co–Nx–C electrocatalysts. Excellent ORR/OER bifunctional electrocatalytic performances are achieved with a small overpotential gap of 0.87 V, and corresponding Zn–air batteries afford higher power density, improved rate performance, and cycling stability for over 200 cycles beyond the noble‐metal‐based electrocatalysts.
As subsidies continue to fall, the technology and cost performance of distributed photovoltaic (PV) determines the progress of its grid parity. Based on the discussion of technology and cost, this ...paper analyzed the economic performance of China's distributed PV industry by utilizing the two indicators of levelized cost of energy (LCOE) and internal rate of return (IRR). The results show that: firstly, the current external environment is generally conducive to the development of distributed PV, but there are still some constraints. Secondly, with the decrease of unit investment cost, distributed PV can achieve the goal of parity before 2025. Thirdly, distributed PV projects in the three types of solar energy resources all have high IRR, and the economic performance is better for the projects with high proportion of spontaneous self-use. At the end of the paper, policy recommendations are offered as references for the government.
•We comprehensively analyzed the technology and cost performance of China's distributed PV.•We focused on the trend and decline path of China's distributed PV costs.•The LCOE of distributed PV in China is expected to achieve full parity in 2025.•Except 100% grid-connected mode, the IRR of distributed PV power plants in three areas is higher than 8% which has shown good economic benefits.
Flexible power sources featuring high-performance, prominent flexibility and raised safety have received mounting attention in the area of wearable electronic devices. However, many great challenges ...remain to be overcome, notably the design and fabrication of flexible electrodes with excellent electrochemical performance and matching them with safe and reliable electrolytes. Herein, a facile approach for preparing flexible electrodes, which employs carbon cloth derived from commercial cotton cloth as the substrate of cathode and a flexible anode, is proposed and investigated. The promising cathode (NVPOF@FCC) with high conductivity and outstanding flexibility is prepared by efficiently coating Na
3
V
2
(PO
4
)
2
O
2
F (NVPOF) on flexible carbon cloth (FCC), which exhibits remarkable electrochemical performance and the significantly improved reaction kinetics. More importantly, a novel flexible quasi-solid-state sodium-ion full battery (QSFB) is feasibly assembled by sandwiching a P(VDF-HFP)-NaClO
4
gel-polymer electrolyte film between the advanced NVPOF@FCC cathode and FCC anode. And the QSFBs are further evaluated in flexible pouch cells, which not only demonstrates excellent energy-storage performance in aspect of great cycling stability and high-rate capability, but also impressive flexibility and safety. This work offers a feasible and effective strategy for the design of flexible electrodes, paving the way for the progression of practical and sustainable flexible batteries.
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Infection is a major obstacle to wound healing. To enhance the healing of infected wounds, dressings with antibacterial activities and multifunctional properties to promote wound ...healing are highly desirable. Herein, gelatin-grafted-dopamine (GT-DA) and polydopamine-coated carbon nanotubes (CNT-PDA) were used to engineer antibacterial, adhesive, antioxidant and conductive GT-DA/chitosan/CNT composite hydrogels through the oxidative coupling of catechol groups using a H2O2/HRP (horseradish peroxidase) catalytic system. The addition of the antibiotic doxycycline endowed the hydrogels with antimicrobial activity to treat infected full-thickness defect wounds. Additionally, CNT-PDA endowed these hydrogels with an excellent photothermal effect, leading to good in vitro and in vivo antibacterial activities against Gram-positive and Gram-negative bacteria. The catechol group and polydopamine imparted tissue adhesiveness, and the hemostatic and antioxidant abilities of these hydrogels were also investigated. The porosity, degradability, swelling, rheological, mechanical, and conductive behaviors of these hydrogels were finely regulated by changing the concentration of CNT-PDA. Hemolysis and cytocompatibility tests using L929 fibroblast cells confirmed the good biocompatibility of these hydrogels. The wound closure, collagen deposition, histomorphological examination and immunofluorescence staining results demonstrated the excellent effects of these hydrogels in an infected full-thickness mouse skin defect wound. In summary, the adhesive antibacterial and conductive GT-DA/chitosan/CNT hydrogels showed great potential as multifunctional bioactive dressings for the treatment of infected wounds.
The L-type amino acid transporter 1 (LAT1; also known as SLC7A5) catalyses the cross-membrane flux of large neutral amino acids in a sodium- and pH-independent manner
. LAT1, an antiporter of the ...amino acid-polyamine-organocation superfamily, also catalyses the permeation of thyroid hormones, pharmaceutical drugs, and hormone precursors such as L-3,4-dihydroxyphenylalanine across membranes
. Overexpression of LAT1 has been observed in a wide range of tumour cells, and it is thus a potential target for anti-cancer drugs
. LAT1 forms a heteromeric amino acid transporter complex with 4F2 cell-surface antigen heavy chain (4F2hc; also known as SLC3A2)-a type II membrane glycoprotein that is essential for the stability of LAT1 and for its localization to the plasma membrane
. Despite extensive cell-based characterization of the LAT1-4F2hc complex and structural determination of its homologues in bacteria, the interactions between LAT1 and 4F2hc and the working mechanism of the complex remain largely unknown
. Here we report the cryo-electron microscopy structures of human LAT1-4F2hc alone and in complex with the inhibitor 2-amino-2-norbornanecarboxylic acid at resolutions of 3.3 Å and 3.5 Å, respectively. LAT1 exhibits an inward open conformation. Besides a disulfide bond association, LAT1 also interacts extensively with 4F2hc on the extracellular side, within the membrane, and on the intracellular side. Biochemical analysis reveals that 4F2hc is essential for the transport activity of the complex. Together, our characterizations shed light on the architecture of the LAT1-4F2hc complex, and provide insights into its function and the mechanisms through which it might be associated with disease.
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