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Ammonia is an important precursor of fertilizers and nitrogen compounds, and it is also a potential energy storage medium and alternative fuel for vehicles. The main ammonia production process is the Haber–Bosch process, which is energy- and capital-intensive. Therefore, it is crucial to find an alternative method for the synthesis of ammonia. In this paper, we reported a new non-noble metal N-doped nanocarbon/Fe3C nanoparticle catalyst (NCF) for the electrochemical synthesis of ammonia, yielding an NH3 production rate of 15.804 μg h−1 mgcat.−1 and Faradic efficiency (FE) as high as 2.72% at −0.4 V vs. RHE at room temperature and ambient pressure in 0.1 M KOH electrolyte. We believe that this work will provide a new opportunity to design a new non-noble metal catalyst for the nitrogen reduction reaction (NRR) and also open a new route to solve the global energy and ecological crisis.

UiO-67, a bifunctional adsorbent, was successfully applied to remove illegal food dyes (Congo red and Malachite green) from aqueous solution. The relevant adsorption conditions were optimized: pH 6, 120 min for contact time, and 10.0 mg L−1 adsorbent dose for Congo red. Adsorption behavior of UiO-67 exhibits a better fitting to pseudo-second-order kinetic model and Langmuir model. Moreover, the maximum adsorption capacities of Congo red (1236.9 mg g−1) and Malachite green (357.3 mg g−1) are higher than that of the most reported adsorbents. Thermodynamic analysis reveals that adsorption processes are spontaneous and endothermic in nature. Powder X-ray diffraction patterns, Fourier-transform infrared spectra and the X-ray photoelectron spectroscopy analysis indicates Zr-OH groups have positive influence on binding of target molecules. What's more, UiO-67 could be reused without significant loss of its capacity after seven cycles. These results prefigure the promising potentials of UiO-67 in food safety risk management.

Multiresponsive fluorescent supramolecular materials are quite interesting, for they combine the multiresponsiveness of supramolecules and the high sensitivity of fluorescent materials. Different from the multiresponsive supramolecular materials based on host-guest interactions, in this report, a supramolecular ionic network was fabricated by 1-(2-aminoethyl)piperazine and citric acids via ionic interactions. Despite the fact that there are no conventional chromophores, the obtained supramolecular ionic material can emit strong fluorescence. Most interestingly, the thin film of this supramolecular ionic material can change its fluorescent intensity in response to four external stimuli, including humidity, triethylamine, acetic acid, and temperature. Beneficial to the supramolecular ionic structure, this multiresponsive fluorescent sensor is self-healable. It is found that a new route has been opened to prepare the multiresponsive fluorescent sensors.

A simple solvothermal synthetic method was proposed for the fabrication of metal organic framework/grapheme oxide hybrid nanocomposite (UiO-67/GO), achieving dense and ordered UiO-67 on the surface of GO for the high-affinity capture of organophosphorus pesticides (OPPs). The composites were characterized by SEM, XRD, FTIR and TGA. The adsorption process and adsorption capacity of glyphosate was evaluated by kinetics and equilibrium adsorption isotherm study, respectively. The results indicate that the pseudo-second-order kinetic model and the Langmuir model correlated satisfactorily to the experimental data. The maximum adsorption capacity of glyphosate on UiO-67/GO is ∼2.855 mmol (482.69 mg) g−1 at pH 4, which catches up with and even surpasses that of most GO-based adsorbents. The excellent adsorption performances of UiO-67/GO toward OPPs are also presented in a wide range of pH 2–8. Moreover, the adsorption mechanism was further revealed using XPS and FTIR. Taking advantage of the abundant Zr OH groups on the surface of GO, as well as the large surface of available GO for enhancing the sequestration of target organophosphorus-pollutants, the as-prepared UiO-67/GO composites exhibit enhancement of adsorption capacity toward glyphosate. The experimental results suggest that the UiO-67/GO is a promising adsorbent for efficient removal of OPPs for the contaminated water purification.

Recently, carbon-based nanomaterials especially carbon dots (CDs) show as the promising candidates for organic contaminant removal because of their abundant functional groups, easy-of-preparation and high surface area. However, the difficulties in separation and recycle of CDs arising from its high water solubility and low molecular weight limit its application in this area. Herein, we demonstrate a one-pot solvothermal method for fabricating NiFe2O4-carbon dot (NiFeC) nanocomposites, which solve its limitations and mitigate the usual fabrication drawbacks by self-assembly such as relatively weak interaction, time-consuming and lack of recycling potential. Series characterizations confirmed the successful fabrication of NiFeC nanocomposites with great uniformity in morphology and exhibited excellent dispersibility in water. The adsorption behavior of the as-prepared nanocomposites was systematically studied using kinetic and equilibrium experiments. Owing to abundant hydroxy and carboxyl groups introduced from CDs, NiFeC nanocomposites offered significantly enhanced tetracycline (TC) removal ability with the maximum adsorption capacity of 591.72 mg g−1, as well as the excellent regenerability. Moreover, XPS and FT-IR analysis revealed the adsorption mechanism was attributed to surface complexation, cation exchange and electrostatic interaction between TC and the NiFeC. With the higher adsorption capacity and simpler synthesis method than traditional adsorbents, NiFeC nanocomposites have promising potential for the removal of TC from wastewater.

Background: The present study aimed to compare the relative abundance of proteins and amino acid metabolites to explore the mechanisms underlying the difference between wild and cultivated ginseng (Panax ginseng Meyer) at the amino acid level. Methods: Two-dimensional polyacrylamide gel electrophoresis and isobaric tags for relative and absolute quantitation were used to identify the differential abundance of proteins between wild and cultivated ginseng. Total amino acids in wild and cultivated ginseng were compared using an automated amino acid analyzer. The activities of amino acid metabolism-related enzymes and the contents of intermediate metabolites between wild and cultivated ginseng were measured using enzyme-linked immunosorbent assay and spectrophotometric methods. Results: Our results showed that the contents of 14 types of amino acids were higher in wild ginseng compared with cultivated ginseng. The amino acid metabolism-related enzymes and their derivatives, such as glutamate decarboxylase and S-adenosylmethionine, all had high levels of accumulation in wild ginseng. The accumulation of sulfur amino acid synthesis-related proteins, such as methionine synthase, was also higher in wild ginseng. In addition, glycolysis and tricarboxylic acid cycle-related enzymes as well as their intermediates had high levels of accumulation in wild ginseng. Conclusion: This study elucidates the differences in amino acids between wild and cultivated ginseng. These results will provide a reference for further studies on the medicinal functions of wild ginseng.

In higher plants, floral signals are mainly collected and transduced to FLOWERING LOCUS T (FT) in Arabidopsis and its orthologues. The movement of FT from leaves to the shoot apical meristem (SAM) is partially mediated by FT-INTERACTING PROTEIN1 (FTIP1). Although the functions of OsFTIP1 in rice and DOFTIP1 in orchid in FT transport have also been investigated, the FTIP1 homologue in lotus (Nelumbo nucifera Gaertn.), a type of horticultural plant with high economic and cultural value, has not been isolated, and the mechanism of NnFT1 transport has not been explored. Here, we revealed that NnFTIP1 mediates the transport of NnFT1 in ectopic transgenic lines in Arabidopsis. Overexpression of NnFTIP1 in the ftip1-1 background rescued the late flowering phenotype of ftip1-1, indicating that NnFTIP1 has a conserved function as FTIP1. NnFTIP1 and NnFT1 share similar tissue expression patterns and subcellular localization. NnFTIP1 and NnFT1 interact both in vitro and in vivo. In addition, NnFTIP1 affects NnFT1 transport from leaves to the SAM. Furthermore, we found that NnUOF8, a MYB-like transcription factor, directly regulates the expression of NnFTIP1. Our results suggest that the functions of FTIP1 and FT are conserved during evolution in flowering plants.

Herein, we demonstrate a one-pot solvothermal synthetic method for fabricating MFe2O4 (M = Mn, Co)–MoS2–carbon dot (CD) nanohybrid composites (MnFMC, CoFMC) with excellent Pb(II) removal ability. Detailed characterization through SEM, XRD, UV-vis spectra, fluorescence spectra and VSM confirmed the formation of the nanohybrid composites. The adsorption behavior of the as-prepared nanohybrids was systematically studied using kinetic and equilibrium experiments, and the adsorption mechanism was further revealed using XPS and FTIR. Taking advantage of the cation substitution of abundant functional groups on the surface of CDs and MFe2O4 nanoparticles, as well as the large surface of available MoS2 for enhancing the sequestration of target metal-pollutants, the as-prepared composites exhibit high adsorption performances (588.24 mg g−1 for MnFMC and 660.67 mg g−1 for CoFMC) and show preferential Pb(II) sorption behavior with a high level concentration of competing cations (Ca(II)/Mg(II)). Moreover, these nanohybrid adsorbents exhibit excellent reusability, lower the effluent Pb(II) contents down to the ppb level, which satisfies the drinking water standard recommended by the World Health Organization, and are promising candidates for water purification.

Multifunctional hydrogels are very interesting, although they might need complex procedures to achieve this goal. Here we report an easily fabricated injectable hydrogel, which is fluorescent, self-healing, pH-sensitive and biodegradable, from hyperbranched poly(amido amine) (HPAMAM) and oxidized alginate (OALG). The HPAMAMs are fluorescent, easy to flow, amine functionalized and biocompatible. OALGs are oxidized products of ALG, a natural polymer, with abundant aldehyde groups. When the two components were injected together, they gelled within 1 minute. The electrostatic force, hydrogen bonds and acylhydrazone bonds are the bases of the HPAMAM/OALG hydrogel. All of them are dynamic in nature. Therefore, this kind of hydrogels is naturally able to heal themselves, sensitive to the variation of pH, and biodegrade after finishing their task. The HPAMAM/OALG hydrogels are of suitable strength and porous structure, which make them good candidates in biomedical applications, from tissue engineering to sustained drug delivery.