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•We report a green chemical method to synthesis the chelating fiber APF and the APF-PAR.•The APF has excellent selective adsorption with Hg2+ and Cu2+, with 435.1 mg/g and 141.7 mg/g ...just in 25–30 min.•The APF-PAR can recognize the Hg2+ just in 2 s, and it can be clearly recognized by naked eyes.•It is the first time to define the solid-base chromogenic sensor to detect heavy metal ions.
To advocate environment friendly detection idea, we adopted the green chemical method to synthesis the 1-(2 amino ethyl) piperidine functionalized polyacrylonitrile fiber (APF) and the chromogenic fiber 4-(2-pyridylazo) resorcinol (APF-PAR). The APF has high adsorption selectivity of Hg2+ and Cu2+, and the change of structure, surface morphology and thermo-stability before and after adsorption have been characterized by the infrared spectra, scanning electron microscope and thermogravimetric analysis. The APF achieved the adsorption equilibrium of Hg2+ just in 25 min and the adsorption capacity is 435.1 mg/g, while the adsorption equilibrium of Cu2+ costs 30 min and the adsorption capacity is 141.7 mg/g. The chromogenic fiber APF-PAR can recognize the Hg2+ and Cu2+ in 2 s, which benefits from the rapid mass transfer and small fluid resistance of the chelating PAN fiber. The color changed from orange to purplish red due to the variation of HOMO-LOMO energy gaps during the reaction which confirmed by the UV–vis absorption spectrum. It also has high selectivity and excellent adsorption performance, which provides more convenient, accurate, reliable and faster testing methods of Hg2+ and Cu2+ in environmental medium.
The rational design of solid electrolytes for the next-generation batteries entails an accurate understanding of ionic transport mechanisms. To elucidate the detailed ion hopping processes in ...different coordinate environments, two solid electrolytes, LiTi2(PO4)3 and Li3Ti2(PO4)3, with the same NASICON-type framework but different sites for accommodating mobile ions, were synthesized and investigated by in situ neutron diffraction and theoretical calculations. The temperature-dependent anisotropic thermal vibrational ellipsoids and migration paths from the maximum entropy method (MEM) indicated that Li ions move faster at higher coordinate architectures, exhibiting three-dimensional (3D) diffusion pathways. In this rhombohedral structure, “one” node (M1 site) out of “three” interconnected transition sites was found to be the lithium configuration of NASICON. Li ions located at the nodes along the 3D pathway in LiTi2(PO4)3 can only drive out another Li-ion species at the node site, while Li ions located at transition sites between two nodes in Li3Ti2(PO4)3 have repulsive force from their five surrounding Li ions. These different configurations lead to distinct overall transport modes. In LiTi2(PO4)3, concerted Li ions transport along a separated chain, while in Li3Ti2(PO4)3, concerted motion occurs along multiple cooperating chains in the 3D channels. Theoretical calculations further indicated that a larger diffusion bottleneck size of Li3Ti2(PO4)3 enables lower hopping energy compared to LiTi2(PO4)3. This study clarifies the detailed ionic hopping processes and the underlying structure–conductivity relationships. Overall, these results elucidate the synergistic events in Li-ion hopping from thermodynamic and kinetic points of view, which will greatly benefit the rational design of solid electrolytes for next-generation batteries.
This work illustrates the effect of voids in LiRAP pellets on lithium dendrite growth and shows that reducing the voids can effectively suppress lithium dendrite growth.
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Solid-state ...lithium-metal batteries, with their high theoretical energy density and safety, are highly promising as a next-generation battery contender. Among the alternatives proposed as solid-state electrolyte, lithium-rich anti-perovskite (LiRAP) materials have drawn the most interest because of high theoretical Li+ conductivity, low cost and easy processing. Although solid-state electrolytes are believed to have the potential to physically inhibit the lithium dendrite growth, lithium-metal batteries still suffer from the lithium dendrite growth and thereafter the short circuiting. The voids in practical LiRAP pellets are considered as the root cause. Herein, we show that reducing the voids can effectively suppress the lithium dendrite growth. The voids in the pellet resulted in an irregular Li+ flux distribution and a poor interfacial contact with lithium metal anode; and hence the ununiform lithium dendrites. Consequently, the lithium-metal symmetric cell with void-reduced Li2OHCl-HT pellet was able to display excellent cycling performance (750 h at 0.4 mA cm−2) and stability at high current density (0.8 mA cm−2 for 120 h). This study provides not only experimental evidence for the impact of the voids in LiRAP pellets on the lithium dendrite growth, but also a rational pellet fabrication approach to suppress the lithium dendrite growth.
•According to the structure of existing amide SDHI fungicides, 40 new coumarin-quinoline amide derivatives were designed and synthesized reasonably. The structures of the compounds were confirmed and ...characterized by 1H NMR, 13C NMR, FT-IR, and HRMS.•The compound 11g was confirmed by single-crystal X-ray diffraction.•Through a series of in vitro activity tests, compounds 11t and 12t were found to have good antifungal activity against Rice sheath blight, which provides theoretical support for further study of SDHI antifungal drugs.•The molecular docking studies of the representative compounds were performed.
Succinate dehydrogenase inhibitors (SDHI) are widely used in plant antifungal agents. To break the barrier of resistance, a series of new coumarin-quinolinamide SDHI derivatives containing monocyclic monoterpenes were designed and synthesized using natural camphor or natural menthol as lead compounds, and their structures were characterized by FT-IR, 1H NMR, 13C NMR and HRMS. In vitro antifungal activity test results showed that the target compounds had inhibitory activity against most plant pathogenic fungi, especially against Rhizoctonia solani and Phytophthora nicotianae var. nicotianae, which was superior to other fungi. Among them, compounds 11t and 12t showed better inhibitory effects on Rhizoctonia solani than the commercial fungicide tricyclazole, with EC50 of 16.90 mg/L and 27.09 mg/L, respectively. Based on this, the detached leaf assay was used to further explore the in vivo therapeutic and preventive effects of compounds 11t and 12t on rice sheath blight in plants. The results of the antifungal activity test in vivo showed that compound 11t was slightly better than the positive control, while compound 12t was close to the control effect of azoxystrobin. More importantly, the more bioactive compounds 11t and 12t did not affect the germination of cowpea seeds and also did not affect the growth of normal human hepatocytes and kidney cells. Molecular docking experiments showed that the introduction of the diethylamino group could promote the formation of hydrogen bonds between the hydrogen atom on the amide bond of the target compound and residue Tyr91, and compounds 11t and 12t had smaller free energy between the amino acid residue, which would enhance the antifungal activity of the compounds. These studies proved the potential value of this series of compounds for the study of novel amide-based SDHI fungicides.
In this work, a unique carbon-doped NiO nanostructure (denoted as C/NiO) was synthesized via a facile precipitation/reduction reaction, followed by a subsequent oxidation process. The successful ...introduction of carbon in NiO gave rise to multiple tailing of the physical and electronic characteristics, including morphology, crystallinity, and conductivity, and valence band edge position. The carbon-doped NiO-fabricated dye-sensitized solar cells actively generated an unrivalled V OC of 0.50 V and also a significantly increased short-circuit current density (J SC, 0.202 mA cm–2), leading to an overall efficiency of 0.053%. The improvement of photovoltaic performance could be mainly attributed to the significantly enhanced charge transport property and retarded charge recombination occurred at the NiO/electrolyte interface. This work provides an extremely simple and effective strategy for incorporating nonmetal elements in semiconductor oxides with remarkably improved photovoltaic performance.
To advocate environment friendly detection idea, we adopted the green chemical method to synthesis the 1-(2 amino ethyl) piperidine functionalized polyacrylonitrile fiber (APF) and the chromogenic ...fiber 4-(2-pyridylazo) resorcinol (APF-PAR). The APF has high adsorption selectivity of Hg
and Cu
, and the change of structure, surface morphology and thermo-stability before and after adsorption have been characterized by the infrared spectra, scanning electron microscope and thermogravimetric analysis. The APF achieved the adsorption equilibrium of Hg
just in 25 min and the adsorption capacity is 435.1 mg/g, while the adsorption equilibrium of Cu
costs 30 min and the adsorption capacity is 141.7 mg/g. The chromogenic fiber APF-PAR can recognize the Hg
and Cu
in 2 s, which benefits from the rapid mass transfer and small fluid resistance of the chelating PAN fiber. The color changed from orange to purplish red due to the variation of HOMO-LOMO energy gaps during the reaction which confirmed by the UV-vis absorption spectrum. It also has high selectivity and excellent adsorption performance, which provides more convenient, accurate, reliable and faster testing methods of Hg
and Cu
in environmental medium.
Uplift modeling is a branch of predictive modeling technology, which is usually used to analyze marketing, advertising and product personalization experiments. In this kind of application scenario, ...we usually do a large number of random experiments to assist decision-making. And thus there is a great need for us to control the number of features as well as tell the most important features in order for the next steps. What's more, in this kind of scenario, the interpretability of features also becomes very important, which means that we should not only pursue the accuracy of prediction, but also minimize the difficulty of controlling the features. However, most existing studies only focus on the accuracy of model prediction, but ignore the cost of controlling and observing too many variables as well as the interpretability of features in practical application. In order to better solve this problem, we introduce a multi head weight calculation method based on causal inference. Instead of selecting features based on the result of machine learning, we manage to select features from the source with causal inference, a total different method from traditional machine learning methods. It can be viewed as a method to solve the problem of overfitting. In our experiment, we use the data from different industries and use different numbers of selected features to evaluate the effectiveness of the proposed feature selection method. The results show that our algorithm significantly improves the performance compared with the feature selection method in standard machine learning theory.
Comparative space-time thinking lies at the heart of spatiotemporally integrated social sciences. The multiple dimensions and scales of socioeconomic dynamics pose numerous challenges for the ...application and evaluation of public policies in the comparative context. At the same time, social scientists have been slow to adopt and implement new spatiotemporally explicit methods of data analy- sis due to the lack of extensible software packages, which becomes a major impediment to the promotion of spatiotemporal thinking. The proposed framework will address this need by developing a set of research questions based on space-time-distributional features of socioeconomic datasets. The authors aim to develop, evaluate, and implement this framework in an open source toolkit to comprehen- sively quantify the changes and level of hidden variation of space-time datasets across scales and dimensions. Free access to the source code allows a broader community to incorporate additional advances in perspectives and methods, thus facilitating interdisciplinary collaboration. Being written in Python, it is entirely cross-platform, lowering transmission costs in research and education.
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•A novel WO3/Ag/CN 2D/2D heterojunction photocatalyst was synthesized.•WO3/Ag/CN showed superior photodegredation of rhodamine B and tetracycline.•Proposed degradation pathways of ...rhodamine B and tetracycline were analyzed.•A Z-scheme photocatalytic mechanism was proposed.
A novel Ag nanoparticles (NPs) decorated WO3 nanoplates/g-C3N4 (CN) nanosheets 2D/2D heterostructure was successfully synthesized by a solvent evaporation and in situ calcination method. The as-prepared WO3/Ag/CN ternary composite exhibited remarkably enhanced photocatalytic activity towards rhodamine B (RhB) and tetracycline (TC) degradation compared with WO3, CN, Ag/WO3, Ag/CN and WO3/CN under visible light irradiation. The enhanced photocatalytic activity could be attributed to the efficient separation of photogenerated charge carriers, the strong redox ability and enhancement of visible-light absorption derived from the construction of Z-scheme 2D/2D heterostructure. Ag NPs not only possess the surface plasmon resonance (SPR) effect, but also act as an electron mediator in Z-scheme heterostructure. The UV–vis absorption spectra analysis indicated that the loading of Ag NPs can enhance the visible-light adsorption. And the decreased photoluminescence and the increased photocurrent demonstrated the high separation rate of photoinduced charge carriers owing to the successful heterojunction construction. Furthermore, the possible degradation pathways of RhB and TC were proposed according to HPLC-MS analysis. The results of radical trapping experiments indicated that O2− and OH were the primary active species during the photocatalytic degradation process.
