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Catalysts of Ni supported on home-made mesoporous alumina (Ni/M-Al2O3) were prepared via facile incipient impregnation method and calcined under different temperature (500–800 °C). Compared with catalysts of Ni supported on commercial alumina, they showed much higher conversion and lower carbon deposition in methane dry reforming (DRM). Among the catalysts, Ni/M-Al2O3-700 exhibited the highest DRM activity, with 77.6% CH4 conversion and 85.4% CO2 conversion at 700 °C. TPR revealed that almost all the Ni was in the form of NiAl2O4 spinel after calcination at 700 °C. Due to the strong metal-support interaction of NiAl2O4 structure, the Ni crystal size of Ni/M-Al2O3-700 after reduction was around 5 nm. TGA and TEM results showed its carbon deposition after 20 h DRM test was only 3.8% and mainly in the form of amorphous carbon. This work indicates that the formation of NiAl2O4 spinel is beneficial to activity and stability towards DRM reaction and controlling calcination temperature is crucial.

Catalysts/co-catalysts for cathodic oxygen reduction and anodic methanol oxidation reactions (ORR/MOR) play the major roles in promoting the commercialization of direct methanol fuel cells. Herein, bimetallic zeolite-imidazolate-frameworks (CoZn-ZIFs) is used as precursor to synthesize Co3O4@NPC/CuO composites as catalysts for ORR and Pt supports/co-catalysts for MOR. The ORR activity (E1/2 = 0.83 V) and long-term stability (activity retention of 85.5% after 30,000 s) of Co3O4@NPC/CuO-400 (400 °C) dodecahedron are better than those of commercial Pt/C (10 wt%) in alkaline electrolytes. The surface CuO with variable valence states (Cu0 and Cu2+) can be used as both the active component for ORR and the protective layer for Co3O4 to enhance catalytic stability. Partial removal of CoOx from carbon framework promotes the exposure of highly active sites (Co2+) on the Co3O4. For MOR, the mass activity of Pt-Co3O4@NPC/CuO-400 (5 wt%) (1947 mA mgPt−1) is much higher than that of Pt/C (751 mA mgPt−1), mainly attributing to that the Pt active sites are uniformly dispersed on Co3O4@NPC/CuO support. The strong interaction between Pt and CuO can reduce the bond strength of Pt-CO to enhance CO resistance. Co3O4 can activate H2O molecules to provide sufficient OH− species to promote MOR. This study provides a new idea for preparation of active ORR catalysts and MOR co-catalyst from bimetallic ZIFs.

We report the synthesis and characterization of a new water-soluble cavitand 1. The container features 2-aminobenzimidazole panels at the "rim" and pyridiniums at the "feet". In the solid state, a single-crystal X-ray structure of the organic-soluble precursor 2 showed a stable vase form. The structure is stabilized by hydrogen-bonded bridges between adjacent panels through solvents and ions. In aqueous solution, binding of hydrophobic and amphiphilic guest molecules to 1 was investigated using 1H NMR. Alkanes, alcohols, acids, diols, and diacids formed 1:1 host-guest complexes, and the guest conformations were deduced from characteristic chemical shift changes. In the presence of [Pd(ethylenediamine)(H2O)2·2NO3], cavitand 1 formed a complex incorporating two metals. The metal-coordinated cavitand also bound hydrophobic linear alkanes and difluorobenzene isomers in aqueous medium. The metallo-cavitand showed shape and size selectivity and was used to separate o-difluorobenzene from its isomers as observed by 19F NMR spectroscopy. The primary amino function of the cavitands offers possibilities for further elaboration to covalent clusters of these container compounds.

Germanium selenide attracts emerging attention for applications in high-performance field-effect transistors and photodetector, due to its unique photoelectric performances and tunable bandgap. Herein, the germanium selenide-reduced graphene oxide (GeSe-RGO) hybrid is successfully synthesized by loading liquid-phase exfoliated GeSe nanosheets on the 2D graphene via a hydrothermal reduction process. It is demonstrated that the photoresponse performance of the photoelectrochemical (PEC) device constructed by the synthesized GeSe-RGO hybrid is significantly enhanced in comparison to the one built by the sole GeSe nanosheets. The results of the PEC tests display the photocurrent density can reach to 8.45 μA/cm2 at the bias of 0.8 V, which is approximately 4 times that of sole GeSe nanosheets. Meanwhile, with the increase of illumination intensity, the photocurrent density of the GeSe-RGO photodetector almost presents a linear increase. When the illumination intensity is 90 mW/cm2, the photoresponsivity value is up to 116 μA/W. In addition, the GeSe-RGO hybrid shows a durable photoresponse capability under the bias of 0 V, revealing that such a hybrid has the excellent self-powered ability in the PEC system. There is no evident degradation on the photoresponsive performance of GeSe-RGO photodetector after 50 light on-off cycling, indicating the good stability of the hybrids. The enhanced performance of the GeSe-RGO hybrid is attributed to the outstanding photoresponsive capability of RGO and the effective separation of photo-generated electron-hole pairs. Our work indicates that the GeSe-RGO hybrid has great prospects for future applications in PEC-type photodetector devices.

Bone mineral consists of calcium hydroxy-carbonate apatite (HCA) that incorporates other minor cation substituents, primarily Na+ (0.5–0.8 wt %). We examine the carbonate species in various HCA spe...

Metalorganic hydrides are a new class of hydrogen storage materials. Replacing the H of N–H or O–H functional groups using metal hydrides have been recently reported, which substantially improved the dehydrogenation properties of heteroaromatic organic hydrides by lowering their enthalpies of dehydrogenation (ΔHd), enabling dehydrogenation at much lower temperatures. Among the reported metalorganic hydrides, lithium carbazolide and sodium carbazolide appear to be the most attractive hydrogen storage/delivery material owing to its high hydrogen capacity (>6.0 wt%) and ideal ΔHd. Nevertheless, the interaction of carbazole and corresponding metal hydride to form metallo-carbazolide is a multistep process involving intensive ball milling and high temperature treatment, where the interaction was not investigated in detail. In this paper, both alkali metal hydrides and amides were employed to react with carbazole to synthesize corresponding carbazolides, aiming to broaden and optimize the synthetic method and understand the reaction mechanism. Our experimental results showed that around one equivalent of H2 or NH3 could be released from the reactions of carbazole and corresponding hydrides or amides, respectively. Instrumental spectroscopic analyses proved that metallo-carbazolides were successfully synthesized from all precursors. It is found that the alkali metal amides (i.e., LiNH2 and NaNH2) with stronger Lewis basicities as metal precursors could synthesize the metallo-carbazolides under milder conditions. Furthermore, quasi in situ nuclear magnetic resonance results revealed that alkali metal could replace H (H–N) gradually, donating more electrons to carbazole ring. Additionally, the solubilized alkali cation may unselectively interact with π-electron of aromatic systems of both carbazole molecules and carbazolide anions via electrostatic cation-π interactions.

Establishing a fast and effective extraction method for herbs is beneficial for the determination of their main compounds and estimating their quality. In this study, deep eutectic solvents (DESs) were optimized to simultaneously extract three main types of phenolic acids, i.e., regaloside B, regaloside C, and regaloside E, and polysaccharides from the bulbs of Lilium lancifolium Thunb. Based on the optimized extraction conditions, i.e., an extraction temperature of 50 °C, an extraction time of 40 min, a solid–liquid ratio of 1 : 25, and a ratio of water in the DES of 20%, the extracted amounts of regaloside B, regaloside C, and regaloside E reached 0.31 ± 0.06 mg g−1, 0.29 ± 0.03 mg g−1, and 3.04 ± 0.38 mg g−1, respectively. The extraction efficiencies were higher than those obtained using conventional organic solvents. Next, the polysaccharide levels were measured and compared with those obtained using a conventional hot water extraction method, and equivalent extraction efficiencies were obtained with the conventional hot water extraction method. This study provides a new application of deep eutectic solvents (DESs) for simultaneously extracting phenolic acids and polysaccharides from the bulbs of L. lancifolium Thunb. Considering the biodegradability and pharmaceutical acceptability, DESs as a class of green solvents could have wide applications in the extraction of natural products.

Fluorophores with photo-modulatory fluorescence properties are valuable for cutting-edge localization microscopy. The existing probes are either photo-activatable, or photo-switchable, but not both. We report a probe (DH-SiR), a leuco-dye obtained by reduction of Si-rhodamine, with both photo-activatable and photo-switchable fluorescence. The potential for super-resolution microscopy was showcased.

We disclose a transition-metal-free decarbonylative alkylation reaction for the synthesis of N-aryl α-hydroxy amides via precise cleavages and reorganizations of three C–C σ bonds. For the first time, a medium-sized cycloalkyl was used as a leaving group to initiate the decarbonylative alkylation process. We also demonstrate the concept of “one-pot” inert C–C bond activation/deuteration. This strategy allows the formation of α,β-deuterated hydroxyamides by using DMSO-d6 as a solvent.

Red pericarp associates with seed dormancy or preharvest sprouting (PHS) tolerance in crops. To identify this association's molecular mechanism, a PHS mutant Osviviparous1 (Osvp1) was characterized in rice and crossed with Kasalath, a red pericarp cultivar with Rc (red coleoptiles) genotype. Among the dehulled seeds of F2 progenies, RcRcvp1vp1 seeds performed a lower PHS rate than rcrcvp1vp1 seeds and showed shallower pigmentation than RcRcVP1VP1 seeds. Kasalath and SL9 (an RcRcVP1VP1 substitution line with Nipponbare background) showed more ABA sensitivity than the Nipponbare (rcrcVP1VP1) by the germination assay, and the transcriptional abundance of ABA signal genes OsABI2, OsSnRK2, OsVP1, ABI5, and especially OsVP1 increased in the red pericarp line SL9. Moreover, OsVP1 can directly bind Rc (bHLH) promoter by yeast one-hybrid, which activates Rc and OsLAR expression in red pericarp rice. Furthermore, a luciferase complementation imaging assay showed that OsVP1 interacts with transcriptions factors Rc and OsC1. These results indicate that OsVP1 promotes proanthocyanidin accumulation through the interaction among OsVP1, Rc, and OsC1 and then increases the plant's ABA sensitivity and PHS resistance.

Understanding self-crystallization characteristics of calcium-magnesium-alumina- silicate (CMAS) glass is of great significance for seeking for solution to its corrosion to thermal barrier coatings (TBCs). Here, we design a series of experiments to investigate the relationship between CMAS self-crystallization behavior and cooling/heating rates and dwell temperature, and emphasize the potential influence of self-crystallization on CMAS corrosion behavior to TBCs. With the cooling rate decreasing, crystalline phases formed in a sequence of diopside, wollastonite and anorthite, and the thickness of the crystalline layer increased. During the heating process, diopside and melilite phases formed when the temperature was lower than 1050 °C; while at higher temperatures, melilite transformed to anorthite and wollastonite, independent on the heating rate. Although self-crystallization can slow molten CMAS penetration, the function on protecting TBCs from damage is limited, and other strategies alleviating CMAS corrosion are necessitated to be developed.

Lattice oxygen undergoes redox reaction to achieve high specific capacity of the material in lithium-rich cathode oxides. However, irreversible oxygen loss causes a change in the crystal structure, and the cations migrate in the transition metal layer, resulting in a rearrangement of the electronic structure and ultimately a severe voltage decay. Herein, we introduce Pt nanoparticles with good catalytic activity and electrical conductivity into lithium-rich cathode materials to improve the loss of lattice oxygen for the first time. We have revealed that the evolution of the lattice structure after the lattice oxygen redox reaction is relatively stable in the lithium-rich oxide with Pt nanoparticles, which is in stark contrast to the apparently deformed crystal structure in the lithium-rich oxide without Pt. Pt-containing electrodes exhibit excellent high-capacity retention rate (more than 80% after 200 cycles), and voltage decay is significantly reduced (less than 0.4 V after 200 cycles). Our results highlight the role of Pt nanoparticles in alleviating the loss of lattice oxygen and stabilizing the crystal structure, which opens up the field of vision for the design of high-energy-density lithium rich cathode oxides with stable structure.

Copper phyllosilicate supported over silica was prepared with ammonia evaporation method. Compared with the catalyst synthesized with conventional impregnation method, this novel catalyst showed a much higher activity and stability towards low-temperature water-gas shift reaction. Various characterization methods indicated the Cu nanoparticle in the catalyst had a superb small diameter around 3 nm, co-existent with abundant Cu+ sites. Based on the analysis via CO-adsorption, DRIFTS and in-situ mass spectrum, it was proved that CO could be adsorbed on Cu+ strongly and Cu+ acted as the active sites for CO activation. The reaction mechanism with dual active sites prevented the competitive adsorption of H2O and CO onto Cu0 sites, thereby improving the catalytic activity and stability.

Blueberry is an important agricultural crop with high nutritional, health, and economic value. Despite the well‐studied blueberry cultivation methods and soil requirements, little is known about how beneficial bacteria function in organic blueberry cultivation systems and their effects on acidic soils. In this study, a single bacteria Bacillus amyloliquefaciens JC65 and three biocontrol bacteria consortiums containing JC65 were applied to organic system. The effect of bacteria to blueberry growth, yield, fruit quality, and soil quality was investigated. A consortium of three mixed Bacillus (B. amyloliquefaciens JC65, B. licheniforims HS10 and B. subtilis 7ze3) showed the highest growth improvement efficiency. The bacterial inoculation increased blueberry leaf chlorophyll content, net photosynthetic rate by 21.50%, 13.21% at 30 days, and increased average plant height by 2.72% at 69 days. Compared with the control, the inoculated plants showed an increased yield of 14.56%. Interestingly, blueberry fruit quality was also improved with supplement of the bacterial consortium. Fruit anthocyanin, soluble sugar, vitamin C, soluble solids, and soluble protein content were increased by 5.99%, 4.21%, 17.31%, 2.41%, and 21.65%, respectively. Besides, beneficial bacterial consortium also enables sustainable agriculture by improving soil ammonium nitrogen and organic matter by 3.77% and 2.96% after blueberry planting. In conclusion, the combination of beneficial bacteria showed a synergistic activity in organic system to promote the blueberry yield, fruit quality, and soil nutrient preservation., We conclude that addition of beneficial microbe in organic blueberry production significantly promotes plant growth and improves blueberry fruit quality. Interestingly, by combination of different beneficial microorganism, the promotion effect on blueberry production was enhanced significantly, indicating synergistic activity among specific mixture of bacteria. The soil retention ability of the beneficial microbe is also shown, especially for increase of soil organic matter.

Here, we report a β-galactosidase (β-Gal)-responsive photochromic fluorescent probe, NpG, that was designed to prebind to human serum albumin (HSA) to form the probe/protein hybrid, NpG@HSA. The formation of NpG@HSA led to an increase in fluorescence emission (520 nm) corresponding to the binding of the fluorescent naphthalimide unit with HSA. In addition, this enabled visualization of the spiropyran fluorescence emission in aqueous media. Our probe/protein hybrid approach afforded a unique imaging platform with enhanced cell permeability and solubility that was capable of visualizing the cellular uptake of NpG@HSA before its activation by β-Gal. The β-Gal-mediated cleavage of the galactose unit within the NpG@HSA hybrid resulted in the formation of NpM@HSA and an increase in red fluorescence emission (620 nm). The resultant merocyanine unit was then able to undergo photoisomerization (merocyanine ↔ spiropyran) to facilitate STORM (i.e., stochastic optical reconstruction microscopy) imaging with minimal phototoxicity and excellent photostability/reversibility. Using STORM, NpG@HSA was able to determine the subcellular distribution of β-Gal activity between cell lines with nanoscale precision. We believe that this system represents a versatile imaging platform for the design of photochromic fluorescent probes suitable for illuminating the precise location of disease-specific biomarkers in various cellular processes.

Wheat stripe rust, caused by Puccinia striiformis f. sp. tritici (Pst), is one of the most important and devastating diseases of wheat; therefore, it is necessary to rapidly and accurately quantify fungicide effectiveness to monitor Pst sensitivity and manage the disease. In this study, a rapid method of quantifying the fungicide effectiveness with detached leaves was developed. The results showed that 0.5% water agar containing 75 μg/ml of 6-benzylaminopurine and filter paper worked the best for maintaining wheat leaves. The disease incidences of different concentrations of spore suspension were compared. When the spore concentrations were 5 and 10 mg/ml, the disease incidences had no significant differences at 12 and 15 days after inoculation (P < 0.05). Fungicide treatment tests revealed that there were no significant differences in the efficacies of triadimefon on rust suppression between detached leaves in the culture dishes and direct spray on seedlings. We also developed a Photoshop software method that can replace the current classification method and accurately measure the proportion of sporulation area on infected leaves. The sensitivity baseline of Pst to triadimefon was estimated as 0.1453 ± 0.0081 μg/ml, and all the values of EC50 were tested for normal distribution using the Shapiro–Wilk test (W = 0.204). The baseline can be used to test the sensitivity of different Pst isolates to triadimefon.

From a multitude of homonuclear and heteronuclear correlation magic-angle-spinning (MAS) NMR experiments, we present thorough structural and phase-quantification analyses of calcium phosphate cemen...

N-glycans on the cell surface provide distinct signatures that are recognized by different glycan-binding proteins (GBPs) and pathogens. Most glycans in humans are asymmetric and isomeric, yet their biological functions are not well understood due to their lack of availability for studies. In this work, we have developed an improved strategy for asymmetric N-glycan assembly and diversification using designed common core substrates prepared chemically for selective enzymatic fucosylation and sialylation. The resulting 26 well-defined glycans that carry the sialic acid residue on different antennae were used in a microarray as a representative application to profile the binding specificity of hemagglutinin (HA) from the avian influenza virus (H5N2). We found distinct binding affinity for the Neu5Ac-Gal epitope linked to the N-acetylglucosamine (GlcNAc) of different branches and only a minor effect in binding for the terminal galactose on different branches. Overall, the microarray analysis showed branch-biased and context-based recognition patterns.

International audience; The ectoparasitic mite, Varroa destructor Anderson and Trueman (Acar: Varroidae), is a major threat for the honey bee, Apis mellifera L. Varroa behavior and physiology are influenced by compounds produced by the honey bee, as well as cues from the general colony environment. As part of our effort to disrupt varroa host chemosensing, we tested 1-allyloxy-4-propoxybenzene, 3c{3,6}, a known feeding deterrent of Lepidoptera larvae and a repellent of mosquitoes of similar activity to DEET. Its effect on varroa mites was evaluated by electrophysiological and behavioral bioassays. Its effect on honey bee chemosensing was also assessed. Compound 3c{3,6} is sensed by honey bees, but the detection of the compound alone by varroa is not clear. The electrophysiological study showed that 3c{3,6} decreases the varroa foreleg responses towards head space odor of nurse bees. However, the response of honey bee antennae towards nurse bee head space odor was not affected. Consistent with electrophysiological studies, in the presence of 3c{3,6}, the ability of varroa to reach any host decreased at the end of the experiment. No lethal effect to the honey bees was recorded. These data showed that 3c{3,6} affects the peripheral olfactory system of varroa by disrupting the chemical recognition process.

The development of effective but earth-abundant electrocatalysts for hydrogen evolution is still a great challenge. Non-noble metal-based multi-phase nanocomposites are regarded as emerging catalysts for efficient catalysts, but their practical application is still hindered by the lack of both satisfying activity and cost-effective synthesis. In this work, ternary CoSe2/MoO2/MoSe2 nanocomposites with controllable phases have been successfully synthesized by simply direct selenization of cobalt molybdate (CoMoO4) nanorods. Compared with related pure Mo-based and Co-based counterparts, the electric conductivity and the active sites of the as-prepared ternary nanocomposites have been both increased due to the synergistic effects. The as-prepared ternary CoSe2/MoO2/MoSe2 nanocomposites electrocatalysts demonstrated superior HER performance which only requiring an overpotential of 229 mV for reaching 10 mA/cm2 current density in acidic media.

This paper empirically investigates the impact of economic growth and industrial structure on China's Nitrogen Oxides (NOx) emissions reduction in a comprehensive Kaya-PLS framework. It is found that the influencing coefficients of economic growth and industrial structure are 0.27 and 2.53, respectively. It indicates that economic growth and industrial structure do bring positive effects on China's NOx emissions, and industrial structure plays a much greater role than economic growth in the process of NOx emissions reduction in China. Moreover, we incorporate additional variables involving energy consumption structure, energy intensity, population and cement production to augment the NOx emissions function. In addition, six scenarios are set to calculate China's NOx emissions for 2019–2030. The prediction results show that China's NOx emissions decreased by 9.11% on average during 2019–2030 because of the decline of the proportion of secondary industry. It means that the decrease of proportion of secondary industry would make a significant decrease for China's NOx emissions. What's more, China's NOx emissions in six scenarios in 2020 are not more than 15.74 million tons, indicating that it is realistic to achieve China's reduction target on NOx emissions according to the 13th Five-Year Plan. Therefore, the government should adjust the energy structure and industrial structure as soon as possible to control China's NOx emissions and improve air quality.

We present a comprehensive composition analysis of calcium phosphate cements (CPCs) incorporating increasing amounts of bioactive pyrophosphate species (up to 17 wt% P2O7). These cements comprise p ...

Ceria has been used for catalyst support for long time due to its unique structural properties resulting from oxygen vacancies and reversible valence change (Ce4+ and Ce3+). In this report, ceria nanorods (NR) and nanocubs (NC) were prepared with hydrothermal method and 5 wt% nickel was loaded on it. The effect of morphology of ceria supports for CO2 methanation reaction was studied. Characterization including TPR, TEM, XRD and XPS shows that Ni/CeO2-NR had a higher number of Ce3+ proportion compared with Ni/CeO2-NC. Both catalysts showed high conversion and selectivity for methane at low temperature range at200–250 °C and interestingly Ni/CeO2-NR exhibited a higher activity than Ni/CeO2–NC. A kinetic study and DRIFTs investigation were carried out to formulate the mechanism. It turned out that CO2 methanation on Ni/CeO2 goes through a formate route instead of CO2 dissociation and the oxygen vacant sites are supposed to be the active sites for the formate formation in this mechanism.

Objective To study the antipyretic and anti-inflammatory constituents from the active fraction of Reduning (RDN) Injection. Methods In this study, the active fraction of RDN Injection was screened by the LPS-induced mouse endotoxin shock model. The chemical constituents were isolated by chromatography on HP-20 macroporous adsorptive resins, silica gel, ODS columns and reverse phase MPLC and HPLC repeatedly, and their structures were elucidated based on spectroscopic analysis (HR-ESI-MS, NMR, ECD) and chemical methods. Meanwhile, we evaluated the anti-inflammatory activities of the isolates by measuring their inhibitory effects on TNF-α production in LPS stimulated RAW 264.7 macrophages. Results The 95% ethanol eluate of RDN Injection by the macroporous adsorption resin column was proved to be the antipyretic and anti-inflammatory active fraction of this injection. A novel iridoid, named jasminoide A (1), and a new guaiane sesquiterpenoid, named (1R,7R,8S,10R)-7,8,11-trihydroxy-4-guaien-3-one (2), were isolated from Reduning injection, and compound 2 can inhibit TNF-α production with IC50 values of 72.24 µmol/L. Conclusion In this study, two new terpenoids were isolated from Reduning Injection, and compound 2 showed inhibitory activity against LPS-activated TNF-α production in RAW 264.7 cells in vitro.

Calycosin-7-O-β-D-glucoside (CG), a methoxylated isoflavonoid in Astragalus membranaceus Fisch. (Bunge), has a wide range of biological activities. Adventitious root culture is an alternative source to obtain active compounds. To improve CG production in A. membranaceus adventitious roots (AMARs), effect of nitrogen concentration, and phosphate concentration on accumulation of biomass, CG, and hydrogen peroxide were investigated. A low concentration of nitrogen promoted growth and CG accumulation in AMARs. Maximum biomass and CG productivity were obtained at a nitrogen concentration of 3 mM. Nitrate, rather than ammonium, was suitable for CG production. Phosphate concentration did not influence biomass accumulation; however, high concentration of phosphate (2.5 mM) was most favorable for CG accumulation. Furthermore, moderate levels of hydrogen peroxide promoted CG accumulation. Optimal concentrations of nitrogen and phosphate were used in scale-up culture of AMARs using a bioreactor. There was a 8- and 2- fold increase in the CG content and antioxidant activity, respectively, using a B5 medium containing 3 mM NO3− and 2.5 mM phosphate when compared to the standard B5 medium, which was equivalent to those observed in field-grown plants. Therefore, optimization of nitrogen and phosphate concentration in the medium is a simple and effective method to economically improve production of CG in AMARs.

In the present work, the geometry, electronic structure, and infrared spectra (IR) of meso-tetra-substituted porphyrin have been investigated theoretically. The optimization of geometries and electronic structure calculations of meso-tetraphenylporphyrin (TPP) and meso-tetra(3-pyridyl)porphyrin (T3PyP) are performed on the basis of density functional theory. The substitution of pyridyl for phenyl in meso-tetra-substituted porphyrins can result into the reduction of molecular size, including the molecular diameter, as well as the size of the central ring of porphin. It has also been found that the molecular orbital energies of T3PyP are smaller than the counterparts of TPP whereas there is almost no change in the HOMO–LOMO gap. Additionally, the infrared spectrum of TPP and T3PyP has been compared in order to determine whether there is a red shift or a blue shift.

For the development of advanced flexible and wearable electronic devices, functional electrolytes with excellent conductivity, temperature tolerance, and desirable mechanical properties need to be engineered. Herein, an alkaline double-network hydrogel with high conductivity and superior mechanical and antifreezing properties is designed and promisingly utilized as the flexible electrolyte in all-solid-state zinc-air batteries. The conductive hydrogel is comprised of covalently cross-linked polyelectrolyte poly(2-acrylamido-2-methylpropanesulfonic acid potassium salt) (PAMPS-K) and interpenetrating methyl cellulose (MC) in the presence of concentrated alkaline solutions. The covalently cross-linked PAMPS-K skeleton and interpenetrating MC chains endow the hydrogel with good mechanical strength, toughness, an extremely rapid self-recovery capability, and an outstanding antifatigue property. Gratifyingly, the entrapment of a concentrated alkaline solution in the hydrogel matrix yields an extremely high ionic conductivity (105 mS cm-1 at 25 °C) and an excellent antifreezing capacity. The hydrogel retains comparable conductivity and eligible strength to withstand various mechanical deformations at -20 °C. The all-solid-state zinc-air batteries using PAMPS-K/MC hydrogels as flexible alkaline electrolytes exhibit comparable values of specific capacity (764.7 mAh g-1), energy capacity (850.2 mWh g-1), cycling stability, and mechanical flexibility. The batteries still possess competitive electrochemical performances even when the operating temperature drops to -20 °C.

Oxidative cleavage reactions of arylalkenes by tert-butyl hydroperoxide that occur by free radical processes provide access to carboxylic acid or ketone products. However, the pathway to these cleavage products is complex, initiated by regioselective oxygen radical addition to the carbon-carbon double bond. Subsequent reactions of the initially formed benzyl radical lead eventually to carbon-carbon cleavage. Thorough investigations of these reactions have identified numerous reaction intermediates that are on the pathways to final product formation, and they have identified a new synthetic methodology for the synthesis of peroxy radical addition-induced hydroperoxide formation.

A copper-catalyzed asymmetric hydrosilylation of β-nitroethyl aryl ketones has been disclosed, and the corresponding chiral alcohols could be obtained in high yields (up to 99% yield) and excellent enantioselectivities (up to 96% ee). Moreover, the reaction worked well on a gram scale with 0.3 mol % of ligand loading, indicating that our protocol has potential applications in the synthesis of important pharmaceuticals such as Tranylcypromine and Ticagrelor.

Twelve undescribed bisindole alkaloids, tabernaemontines A–L, were simultaneously isolated from the leaves of Tabernaemontana bovina and their structures were elucidated by spectroscopic methods. All alkaloids consist of two Aspidosperma-type units with various intramolecular linkages. Particularly, tabernaemontines A–D were assembled through C-3/14′ with a large angle strain, whilst tabernaemontines E–K adopted a preferential conformation. Tabernaemontine L was assembled via a C-14/10′ connection. Tabernaemontines F, K and L showed good inhibition of microglial activation. As a representative of Aspidosperma-type dimers, the P38 MAPK activation inhibition properties of tabernaemontine F were tested. The promising results revealed this compound as a potential candidate for the treatment of chronic neurodegenerative diseases.

Surfactant-assisted enzymatic hydrolysis was used to extract the flavor compounds from piper nigrum L. The extraction conditions were optimized through orthogonal and single-factor experiments. The extracted piperine content, measured with High-Performance Liquid Chromatography (HPLC) and UV spectrophotometric, was used as experimental index. The optimized conditions were as follows: the amount of cellulase, neutral protease and surfactant (sodium stearoyl lactylate) addition was 0.08%, 0.1% and 0.4% (w/w) respectively. The solid–liquid ratio was 1:5 (g/mL), the enzymolysis temperature and time were 60°C and 4 h, and the granularity was less than 10 mesh. Under these conditions, the content of the extracted piperine was 4.54% (UV spectrophotometric) and 4.42% (HPLC), respectively. Meanwhile, the mechanisms of the enzymatic reaction, as well as the role of the surfactant in enzymatic hydrolysis process were discussed.

Carbon nanofibers (CNFs) were prepared by electrospinning, and silver (Ag) ions were grown on the surface of the CNFs by in situ solution synthesis. The structure and morphology of obtained Ag-doped CNFs (Ag-CNFs) were characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM). The gas sensibility of the composite fiber was investigated by ammonia (NH3) obtained by natural volatilization from 1 to 4 mL of NH3 solution at room temperature. It was found that the fibers exhibited a sensitive current corresponding to different NH3 concentrations and a greater response at high concentrations. The sensing mechanism was discussed, and the good absorptivity was demonstrated. The results show that Ag-CNF is a promising material for the detection of toxic NH3.

A new mechanism of La-catalyzed amidation of N-methylbenzylamine with p-chlorobenzaldehyde has been computationally proposed, where L2La[NR1R2] (I) rather than previously proposed L2La[OCHRNR1R2] (II) is the catalytically active species. Interestingly, the side-product alcohol acting as a proton relay to reduce reaction energy barrier could participate in the regeneration of I. Besides, DFT calculations suggest that an addition of alcohol additive into the initial reaction system could accelerate the reaction, which has been further verified by experiments.

Silicon germanium (SiGe) alloys hold promise for thermoelectric power generation at high temperatures and have been applied in deep-space missions. However, enhancement of the dimensionless thermoelectric figure-of-merit (ZT) is still needed for practical civil applications of SiGe. In this work, we report high-performance oxide/SiGe bulk composites that were obtained via hot-press sintering of mixed powders composed of phosphorus (P)-doped SiGe prepared via mechanical alloying, using a ball-milling technique and La-Nb-doped SrTiO3 (La-Nb-STO). The La-Nb-STO powder was obtained from ball milling of a bulk La-Nb-STO sample that was sintered via hot pressing of hydrothermally synthesized La-Nb-STO powder. Controlling the amount of La-Nb-STO nanoparticles added to SiGe matrix increased the power factor by optimizing the electron concentration and mobility in the composite. In addition, compared with single-phase P-doped SiGe, the second phase decreased the thermal conductivity because of additional phonon scattering at the interface. As a result, a high ZT of 0.91 was realized in the n-type oxide/SiGe bulk composite at 1000 K, which was 18% larger than that for the typical materials used in space flight missions and 5% higher than the single-phase SiGe alloys obtained in the present study. The strategy used in this study could also be viable to further enhance the ZT of nanostructured n-type SiGe and SrTiO3-based oxide materials.

Calcite/zeolite mixture (CZ) can be used to construct a capping layer for the simultaneous management of phosphorus (P) and nitrogen (N) liberation from sediments into the overlying water (OVER-water). However, its control efficiency of sedimentary P release still needs to be improved. To address this issue, an iron-modified CZ (Fe-CZ) was synthesized, characterized, and employed as a capping material to simultaneously prevent P and N release from sediments into OVER-water. Batch and microcosm incubation experiments were performed to study the efficiency and mechanism for the control of P and N release from sediments by capping Fe-CZ. Results showed that sediment capping with Fe-CZ resulted in the significant reduction of soluble reactive P (SRP) and ammonium-N (NH3-N) in OVER-water, with reduction rates of 77.8–99.7% and 54.0–96.7%, respectively. Furthermore, the Fe-CZ capping layer decreased the SRP concentration in the pore water (PORE-water) at depth of 0–30 mm and reduced the concentration of PORE-water NH3-N at depth of 0–50 mm. Moreover, the Fe-CZ capping layer gave rise to the great decrement of the concentration of the labile P measured by DGT (diffusive gradient in thin films) technology (P-DGT) in the profile of OVER-water and sediment. Additionally, the Fe-CZ capping resulted in the reduction of redox-sensitive P (P-BD) in the 0–50 mm sediment and caused the transformation of P-BD to calcium-bound P (P-HCl) and residual P (P-RES) in the 0–10 mm sediment as well as to P-RES in the 10–20 mm sediment. Results of this work indicate that the Fe-CZ capping has a high potential for the simultaneous management of P and N release from sediments, and the decrease of the contents of sediment P-DGT, sediment P-BD, PORE-water SRP and PORE-water NH3-N as well as the conversion of mobile P to more stable P in the top sediment should have a significant role in the simultaneous interception of sedimentary P and N liberation into OVER-water by the Fe-CZ capping.

In order to effectively deal with large amounts of complex organic pollutants in the harmful distillation residues with low energy consumption, a novel two-stage fluid-bed/fixed-bed system was designed to catalyze oxidation of acrylic acid production residue. The effects of fluid-bed temperature, gaseous hourly space velocity (GHSV), and oxygen excess rate on the purification of acrylic acid production residue in the two-stage fluid-bed/fixed-bed system were studied to prove the feasibility of the method. The chemical oxygen demand (COD) of the discharged liquid was

With reduced dehydrogenation enthalpy change and reduced dehydrogenation temperature compared with its phenol-cyclohexanol pair, sodium phenoxide-cyclohexanolate pair developed recently is promising for large-scale energy storage and long-distance hydrogen transportation. In the present work, we investigate the kinetic behavior of the pair in the hydrogenation and dehydrogenation in water over three commercial catalysts. It is shown that 5% Ru/Al2O3 and 5% Pt/C perform well in the hydrogenation and dehydrogenation, respectively. Kinetic analyses show that the hydrogenation of sodium phenoxide is of first-order with respect to H2 pressure and zero-order to the concentration of sodium phenoxide in the presence of Ru/Al2O3 catalyst. >99% conversion of cyclohexanol and >99% selectivity to phenoxide can be achieved in the dehydrogenation catalyzed by Pt/C catalyst and in the presence of NaOH at 100 °C, where cyclohexanone was observed as an intermediate. According to the kinetic analysis, the hydrogenation of sodium phenoxide may undergo the hydrolysis and hydrogenation pathway. For the dehydrogenation, an intermediate, i.e., cyclohexanone, was detected and two possible pathways are proposed accordingly.

A Ni-catalyzed 1,2-acyl migration triggered by C–C bond cleavage was developed. The process of 1,2-acyl migration followed by olefin isomerization provides a convenient access to α,β-unsaturated ketones, which are well-known building blocks in organic synthesis. Experimental and computational studies show that the selective β-hydride elimination and Ni-hydride reinsertion play an essential role in this reaction.

From a suite of advanced magic-angle spinning (MAS) NMR spectroscopy and powder X-ray diffraction (PXRD) experiments, we present a comprehensive structural analysis of pyrophosphate-bearing calcium ...

Design of hollow carbon structure by using metal-organic-frameworks (MOFs) precursors has come under the spotlight in electrochemical energy related applications due to its structure advantages. Here, a bimetal-based MOF (Zn and Fe) is adopted to synthesize hollow carbon nanobox with encapsulation of FeP nanoparticles. An unique core-shell architecture consisting of Zn-Fe Prussian blue analogue (PBA) core and polydopamine shell is first synthesized, followed by pyrolysis-oxidation-phosphorization process to prepare monodispersed FeP nanoparticles encapsulated in hollow carbon nanobox (denoted as FeP/HCNB). Electrochemical hydrogen evolution activity is chosen to investigate the structure advantage of FeP/HCNB. It achieves overpotentials of −88 mV and −180 mV at 10 mA cm−2 in acidic and alkaline solutions, respectively, and continuous operation for 15 h (start at 20 mA cm−2). It is therefore expected that the synthetic strategy of nanobox would enlighten the preparation of various nanostructures for different applications.

In the present work, Zn-incorporated TiO2 coatings are prepared through a one-step micro-arc oxidation (MAO) method on a grade 4 pure titanium with the addition of either Na2Zn-EDTA solution or ZnO nanoparticles (NPs) as Zn sources. The microstructural features of both Zn-incorporated TiO2 coatings were systematically examined. It is revealed that different Zn sources result in significant difference of phase component, chemical state, composition and morphology between the resultant Zn-incorporated MAO coatings. Zn species could be present as ZnO and Zn(OH)2 in the coating when Na2Zn-EDTA was used as Zn source whereas the presence of ZnO nano-clusters is obvious on the coating surface with ZnO NPs as Zn source. The addition of ZnO NPs during the MAO process also leads to a lower Zn content of the resultant coating, which is more defective with increased thickness in comparison to that of Na2Zn-EDTA. Further, antibacterial property and osteogenic activity of both Zn-incorporated coatings were examined. Both Zn-incorporated coatings exhibit favourable bacterial inhibition ability and bone formability, suggesting the successful synthesis of bifunctional coatings through the facile one-step micro-arc oxidation method.

From a large ensemble of 34 silicate-based glasses from the borosilicate, phosphosilicate, and borophosphosilicate systems that comprise either Na as a sole glass-network modifier or when mixed wit ...

We describe new container host molecules - deep cavitands with benzimidazole walls and ionic feet - to recognize highly hydrophilic guest molecules in water. The aromatic surfaces of the cavity recognize hydrophobic portions of the guest while bound water molecules mediate hydrogen bonding in the complex. Spectroscopic (NMR) evidence indicates slow in/out exchange on the chemical shift timescale and thermodynamic (ITC) methods show large association constants (Ka up to 6 × 104 M-1) for complexation of small, water-soluble molecules such as THF and dioxane. Quantum chemical calculations are employed to optimize the host-guest geometries and elucidate the hydrogen bonding patterns responsible for the binding.

Novel chiral ionone alkaloid derivatives were synthesized and their antimetastatic effects were evaluated in human breast cancer cells using chemotaxis assay. Compared with positive control LY294002, a PI3 K inhibitor, derivatives 10 a, 11 a, 11 c, 11 g, 11 j, 11 k and 11 w exhibited significant inhibitory effects against cancer cell migration. Especially, the IC50 for compound 11 g was as low as 0.035±0.004 μM. Further investigations on compound 11 g revealed that it could exert inhibitory effects on the adhesion, migration and invasion of MDA-MB-231 cells. The mechanisms for the antitumor metastatic effects of 11 g might be through the inhibition of HIF-1α/VEGF/VEGFR2/Akt pathway, which suppressed the downstream signaling molecules, including Akt1/mTOR/p70S6K and Akt2/PKCζ/integrin β1 pathways. Taken together, chiral ionone alkaloid derivative 11 g has the potential to be developed into an antitumor metastatic agent for breast cancer.

The next generation of high-performance flexible electronics has put forward new demands on the development of ionic conductive hydrogels. In recent years, many efforts have been made toward developing double-network (DN) hydrogels due to their excellent mechanical properties and unique network structures. However, profound challenges remain in achieving controllable surface morphology and multifunctional integration within DN hydrogels. In this work, we report the fabrication of a multifunctional DN hydrogel by multiple cross-linking between an innovative K+-containing poly(ionic liquid) (PIL) and κ-carrageenan. The resulting hydrogel possesses fascinating physicochemical properties, ranging from remarkable mechanical properties and machinability to adjustable surface morphology and superior adhesion ability. The extremely versatile DN hydrogels exhibited outstanding potential for the future of wearable strain sensors in real-time monitoring of human health, and the optimized design strategy opens new possibilities for the fabrication of multiscale structured and multifunctional integrated ionic conductive hydrogels.

A mutant of the ridgetail white prawn, which exhibited rare orange-red body color with a higher level of free astaxanthin (ASTX) concentration than that in the wild-type prawn, was obtained in our lab. In order to understand the underlying mechanism for the existence of a high level of free astaxanthin, transcriptome analysis was performed to identify the differentially expressed genes (DEGs) between the mutant and wild-type prawns. A total of 78,224 unigenes were obtained, and 1863 were identified as DEGs, in which 902 unigenes showed higher expression levels, while 961 unigenes presented lower expression levels in the mutant in comparison with the wild-type prawns. Based on Gene Ontology analysis and Kyoto Encyclopedia of Genes and Genomes analysis, as well as further investigation of annotated DEGs, we found that the biological processes related to astaxanthin binding, transport, and metabolism presented significant differences between the mutant and the wild-type prawns. Some genes related to these processes, including crustacyanin, apolipoprotein D (ApoD), cathepsin, and cuticle proteins, were identified as DEGs between the two types of prawns. These data may provide important information for us to understand the molecular mechanism of the existence of a high level of free astaxanthin in the prawn.

Membrane camouflaged-nanoparticles (CM-NPs) have been exploited to inherit desired functionalities from source cells. Despite those advantages, membrane cloak may play a "double-edged sword" role in tumor-targeting therapy, as the intact membrane coating may hinder function-exertion of loaded drugs after reaching predetermined site. Therefore, further optimization of CM-NPs is still needed to enhance their delivery efficiency. Herein, natural product, Solamargine (SM), a cholesterol-affiliative amphiphilic potato alkaloid is first applied as core component of "inner core," to design a cell-mimicking "core-shell" nanoparticle (RBC-SLip) with acid-responsive off-coating properties for tumor-targeted therapy. Owing to red blood cell membrane (RBCm)-derived outer coating, it circulates stably in physiological conditions. While it would undergo an off-coating morphological change in response to acid stimuli in tumor microenvironment (TME), afterwards, the resulting off-coating liposome (SLip) shows active tumor-targeting and endosomal escape abilities, thus contributing to superior antitumor efficacy. In addition, SM also possesses natural TME-modulating ability; therefore, RBC-SLip can synergize with the PD1/PD-L1 blockade immunotherapy when encapsulated with PTX to achieve enhanced chemoimmunotherapy. The off-coating strategy developed by natural products SM, provide a brand-new perspective to optimize CM-NPs, and it also embodies application value of "unification of medicines and excipients" of natural products.

Cucumber powdery mildew caused by Sphaerotheca fuliginea is a leaf disease that seriously affects cucumber’s yield and quality. This study aimed to report two nucleotide-binding site-leucine-rich repeats (NBS-LRR) genes CsRSF1 and CsRSF2, which participated in regulating the resistance of cucumber to S. fuliginea. The subcellular localization showed that the CsRSF1 protein was localized in the nucleus, cytoplasm, and cell membrane, while the CsRSF2 protein was localized in the cell membrane and cytoplasm. In addition, the transcript levels of CsRSF1 and CsRSF2 were different between resistant and susceptible cultivars after treatment with exogenous substances, such as abscisic acid (ABA), methyl jasmonate (MeJA), salicylic acid (SA), ethephon (ETH), gibberellin (GA) and hydrogen peroxide (H2O2). The expression analysis showed that the transcript levels of CsRSF1 and CsRSF2 were correlated with plant defense response against S. fuliginea. Moreover, the silencing of CsRSF1 and CsRSF2 impaired host resistance to S. fuliginea, but CsRSF1 and CsRSF2 overexpression improved resistance to S. fuliginea in cucumber. These results showed that CsRSF1 and CsRSF2 genes positively contributed to the resistance of cucumber to S. fuliginea. At the same time, CsRSF1 and CsRSF2 genes could also regulate the expression of defense-related genes. The findings of this study might help enhance the resistance of cucumber to S. fuliginea.

A series of nickel-ceria catalysts were prepared with the hydrothermal method and the composition of solvents was adjusted. The performance of the catalysts on CO2 methanation varied greatly with the volume ratio of ethylene glycol/water in the hydrothermal process. Among them, the catalyst denoted as CN-70-70EG exhibited the highest catalytic activity with a CO2 conversion of 67.8 % at 375 °C. Catalysts were characterized by XRD, BET, H2-TPR, CO2-TPD, XPS, Raman, UV–vis DRS, SEM mapping and in-situ DRIFTS. It was revealed that the catalytic performance was dependent on the nickel dispersion, the number of surface oxygen vacancies and the ability of the catalysts to be activated at low temperatures. In-situ DRIFTS experiments showed that CO2 was initially adsorbed in the forms of carboxylate, carbonate and bicarbonate on the ceria sites. These adsorbed species reacted with the dissociated H to produce the main intermediate of formate species. The adsorbed CO was only a side product, rather than intermediate species. Furthermore, DRIFTS experiments on hydrogenation of methanol and formic acid demonstrated that these two species could be converted into methane with the presence of the catalysts. In both situations, methoxy species bonded to surface Lewis acid sites were found to be intermediates in this reaction.

The ridgetail white prawn, Exopalaemon carinicauda is one of the most valuable marine resources in China, but few studies have been conducted to describe the characteristics of the simple sequence repeats (SSRs) for this species. The present study provides a genome‐wide view to SSRs in E. carinicauda. A total of 3,243,071 SSRs were detected in the whole genome sequences, while the mononucleotide SSR was the most abundant type. Adenine and Thymine (AT)‐rich SSRs were more abundant than guanine and cytosine (GC)‐rich SSRs. These SSR resources will be very useful for genetic studies such as parentage assignment, genetic diversity evaluation, and marker‐assisted selection. Sustainable development of E. carinicauda aquaculture requires improved breeding stocks and systematically family‐based selective breeding that relies on accurate pedigree information for estimating genetic merits. Therefore, eight highly polymorphic SSRs were selected for parentage assignment analysis. A total of 180 individuals from the offspring of four full‐sib and two half‐sib families were used to examine the efficacy of parentage analysis of those SSRs. The results showed that 98% of the offspring were unambiguously assigned to their female parent. The high efficacy of parentage assignment showed that the developed polymorphic SSR markers could be used for selective breeding in E. carinicauda.