The abuse of antibiotics has led to the enhancement of bacterial drug resistance, which has aroused widespread concern. In our study, an unusual polymer (PADAAC) with aldehyde, vinyl and azo groups was obtained by copolymerization of allyl diazoacetate (ADA) and acrolein (AC). We fabricated a series of hydrogels (PA0AM, PA5AM, PA10AM and PA20AM) by incorporation PADAAC into the acrylamide and N, N’-methylene bis(acrylamide) networks, which can suppress bacterial growth and kill the bacteria with > 95%. All the hydrogels possessed low cytotoxicity. More remarkably, the aldehyde groups were protected amino groups via a simple imine reaction. Protected PA20AM had no effect on the bacteria, while deprotected PA20AM recovered its antimicrobial property against Staphylococcus aureus (killing efficiency: 96.1%), Escherichia coli (killing efficiency: 98.3%) and methicillin-resistant Staphylococcus aureus (MRSA) (killing efficiency: 95.0%) after removing the amino groups. PA20AM and deprotected PA20AM also exhibited good antimicrobial property in vivo.

The flexible supercapacitors have attracted tremendous attentions, but challenges still remain in seeking suitable electrode materials to enhance the energy density and other aspects. To this end, a unique Polypyrrole (PPy)-reduced graphene oxide (rGO) Janus-faced film is prepared through a facile and scalable method consisting of the deposition of graphene film on the surface of copper foil via a Cu||GO electrochemical cell followed by the self-assembly of PPy at the heterogeneous interface. Such a distinctive structure, in which the PPy layer acts as the source of high pseudo-capacitance, while the graphene layer is employed as the “high way” for rapid electron transport and as well as the strong π-π coupling effect between graphene and polymer nanosheets, endows the resultant electrode ultra-high specific capacitances (1380 mF cm-2 at 1 mA cm-2) and excellent rate capability (65.1% capacitance retention with the current density increases to 20 mA cm-2). Furthermore, the assembled PPy-rGO//PPy-rGO symmetric supercapacitors deliver a maximum energy density of 31.95 Wh L-1, remarkable cyclic stability (89.7% capacitance retention after 10000 cycles) and superior mechanical property (82% capacitance retention after 8000 cycles under different bending conditions).

A micro-scale analysis of mass transport in ceramic foams that are used as catalyst supports in gas phase reactions is of high interest. Although the effects of flow rate and foam parameters on the radial and axial dispersion are known for liquid flows, no pore-scale experimental analysis has been yet reported to correlate the mechanical and diffusional dispersion of gas flows to the geometry of open-cell foams. Here, a spatially resolved Pulsed Field Gradient NMR method is applied to determine dispersion coefficients of thermally polarized gas along axial and transversal directions of open-cell foams. The comparative study of three commercial foam samples with different morphologies shows the effect of open porosity, window size, and flow rate on gas dispersion. Additionally, the influence of mechanical and diffusional dispersion at each flow rate is investigated for individual samples. By observing the transition from diffusional dispersion to mechanically driven dispersion of gas, it is found that diffusional dispersion plays an important role, even at higher flow rates after a transition from Darcy to Darcy-Forchheimer regime occurs. The measured values for dispersion coefficients of methane can be directly used in pseudo-heterogeneous models for the methanation reaction.

The discovery of ultra-broadband VIS-NIR emission phosphors is a major challenge for miniature/portable devices in special applications like bio-sensing. In different solid materials, the Eu2+ broadband emission usually covers the blue to red spectral region. The near infrared spectral range is extremely difficult to obtain with the activator Eu2+, even in nitride host materials. In this work, we design and report a record-breaking oxide-based phosphor, Ba3ScB3O9:Eu2+, which yields VIS-NIR light (510 -1100 nm) in response to ultraviolet-blue light excitation. Under a preferred excitation at 376 nm, Ba3ScB3O9:Eu2+ shows a broadband long-wavelength emission with the main peak, full width at half maximum and Stokes shift of 735 nm, 205 nm and 12991 cm-1, respectively. The spectral position and band width can be rationalized by combining the nephelauxetic effect and crystal field. By covering the title phosphor on a blue LED chip (450 nm), a VIS-NIR pc-LED containing Eu2+ emission with NIR out power of 2.3 [email protected] mA and photoelectric efficiency of 9.3%@100 mA is obtained. According to ultra-broadband emission in visible-near infrared region, application in LEDs for real-time non-destructive examination occurs promising.

Herein, a novel polyelectrolyte complex (PEC) hydrogel film has been fabricated through self-assembly of two oppositely charged polysaccharides salecan and carboxymethyl chitosan (CMCS) for Pb2+ removal. The formation of PEC network structure via electrostatic interactions was confirmed by FT-IR, XRD, XPS and TGA. The change of salecan/CMCS ratio had obvious influence on the swelling capacity, morphology and rheological properties of the hydrogel films. The adsorption capacity of Pb2+ was specifically investigated by tuning the salecan/CMCS ratio, other ions, pH, ion concentration and contact time. Furthermore, the equilibrium isotherms were better fitted with Langmuir model, indicating monolayer adsorption behaviour. The maximum adsorption capacity of Pb2+ according to Langmuir model was 418.4 mg/g, higher than that of some other adsorbents. The adsorption kinetics was well modelled by pseudo-second-order and Crank model, suggesting chemisorption and internal diffusion control mechanism. The PEC hydrogel film also exhibited excellent reusability after 5 adsorption/desorption cycles without obvious changes in the adsorption capacity. Overall, these results not only highlight a new idea for the utilization of salecan, but also provide a green method for the rational design of highly efficient adsorbent for Pb2+ removal.

Though microalgal-bacterial consortium in photobioreactor (PBR) has been investigated to the anaerobically digested centrate (ADC) treatment, the impact and degradation of micropollutant sulfamethoxazole (SMX) in this system has never been reported. In this research, three microalgal-bacterial consortiums were parallel operated with suspended Chlorella vulgaris (C. vulgaris), immobilized C. vulgaris and immobilized C. vulgaris-powdered activated carbon (PAC), namely PBR (SCV), PBR (ICV) and PBR (ICV+PAC), respectively. The impact of SMX on the ADC treatment performance, C. vulgaris growth and microbial community shifts were investigated. The performance of SMX removal and potential SMX degradation mechanism by the microalgal-bacterial consortium were explored. The results showed that SMX significantly inhibited PBR (SCV) with unsatisfactory C. vulgaris growth, ADC treatment and SMX removal. Comparatively, immobilized microalgae beads protected microalgae in PBR (ICV) and PBR (ICV+PAC) obtaining higher proportion of living C. vulgaris of 85.1% and 86.2%, respectively, comparing to that of 74.6% in PBR (SCV) (p < 0.05). Moreover, microalgae immobilization coupled with PAC adsorption mitigated toxicity of SMX and accelerated the formation of stable microalgal-bacterial consortium. Thus, PBR (ICV+PAC) obtained the maximum SMX removal (99.0 ± 0.2%) and the highest ADC treatment performance (COD, TN and TP removal of 72.12 ± 1.34 %, 98.47 ± 0.69 % and 98.49 ± 0.73 %, respectively). Bacterial diversity was dramatically reduced by SMX in the PBR (SCV), which was significantly mitigated by microalgae immobilization in PBR (ICV) and PBR (ICV+PAC). The enrichment of functional genera Pseudomonas, Brevundimonas and Hydrogenophaga were conducive to SMX degradation; while the dominant microalgae of specie of C. vulgaris was not perturbed by SMX. The pathways of SMX degradation involved oxazole ring fracture, mononitration effect, S-N bond and C-N bond broken. This research revealed the inhibition of SMX on PBR (SCV) and demonstrated the potential of PBR (ICV+PAC) on SMX degradation with simultaneous ADC treatment.

Isosorbide (ISB), one of the important polyols, can be produced through the sequential intramolecular dehydration of sorbitol (SL) derived from an abundance renewable biomass resources. The advantages of its rigid structure have granted the ISB a wide application in the polymer industries. An acidic catalyst in the liquid phase was conventionally used in the dehydration process. This homogeneously catalysed reaction gave low ISB yield and required additional downstream processes to separate the catalyst. The present study employed solid acidic ion exchange resin, Amberlyst 36 in the SL dehydration at a mild condition. The effect of important operating parameters such as stirring speed, catalyst loading, temperature and reaction time was investigated. The increase of catalyst loading from 5 to 7 wt% did not significantly affect the ISB yield. A higher temperature increased the reaction rate whereas a prolonged reaction time increased the conversion of SL and yield of ISB to the maximum. In terms of giving a higher ISB yield during SL dehydration, AM 36 was found to outperform the other resin catalysts reported in the literature. Both SL conversion and ISB yield of >99% were recorded after a 4 h reaction at 423 K with catalyst loading of 5 wt% and stirring speed of 300 RPM. The reaction kinetics was evaluated under a mass transfer resistances free condition at the reaction temperature ranged from 373 K to 423 K. The kinetic data well fitted to the Langmuir-Hinshelwood (LH2) model that took side reaction into account. The activation energy for dehydration SL to ST, dehydration ST to ISB and dehydration of SL to other side products such as humins were 109.22, 109.46 and 104.17 kJ/mol respectively.

Hydrothermal carbonization aqueous phase (HTC-AP) can be used for methane production by anaerobic digestion (AD). However, it generally had low conversion efficiency due to the formation of complex dissolved organic matters, which depends upon the components of biomass. The present study investigated the characteristics, methane potentials, and recalcitrant chemicals of HTC-AP produced from different combinations of model compounds carbohydrate (α-cellulose, C) and protein (bovine serum albumin, BSA) with mass ratios of 1:0, 0.75:0.25, 0.5:0.5, 0.75:0.25 and 0:1. The methane yields of samples 1:0 (pure C) and 0:1 (pure BSA) were 192 mL/g COD and 187 mL/g COD, respectively, while it was decreased to 105.5 CH4 mL/g COD for sample 0.75:0.25 (C/BSA), indicating more recalcitrant organics were produced with the combination of C and BSA. It was found that the mean MW (209157) of sample 0.75:0.25 was much higher than the other samples (<7000 Da). While the highest percentage (51 %) of hard bio-degradable hydrophobic DOC, humics, and building blocks organics were also observed in this sample by LC-OCD-OND analysis. Furthermore, a high value of SUVA index 2.56 was noted, indicating the presence of a large number of aromatic compounds. In addition, fluorescent compounds mainly relating to humic-like substances were also detected by 3D-EEM. GC-MS analysis showed higher concentrations of pyrazine and its derivatives were present in sample 0.75:0.25, which indicated the occurrence of a serious Maillard reaction. The continuous experiment further verified the lower biodegradability of sample 0.75:0.25 with a methane yield of 108 mL/g COD. It also showed that only 18.9 % of the fluorescent components were degraded and 13 recalcitrant chemicals were identified to be hard bio-degradable organics in AD process.

Sulfur dioxide, formed in combustion of sulfur-rich fuels in diesel engines, may oxidize and react with water to form corrosive H2SO4. However, the SO2 may also be absorbed in the lube oil and consume CaCO3-containing reverse micelles. In this study, the CaCO3 + SO2 reaction was investigated in a batch reactor setup at temperatures and pressures similar to those on the cylinder liner in an engine. The conversion of CaCO3 and the formation of products were determined by Fourier Transform Infrared Spectroscopy (FTIR). CaSO3 was the main product, but CaSO4 was observed at extended residence times and increased temperature. The SO2-CaCO3 reaction exhibited only a small temperature dependence; the increase in the rate constant with temperature was partly off-set because the absorption of SO2 in the lube oil emulsion decreases at increased temperature. The reaction rate increased slightly with the initial water concentration due to increased SO2 absorbance. A mathematical model for the batch reactor was set up and kinetic parameters were determined by fitting predictions to the experimental data. The model was then used to predict the CaCO3 conversion in lube oil from SO2 for conditions relevant to a full-scale engine application. Simulations showed that consumption of CaCO3 from SO2 is insignificant in a two-stroke marine diesel engine application and that the H2SO4-CaCO3 reaction is far more important than the SO2-CaCO3 reaction.

This work presents the enhanced numerical simulation of the radiation transport in three different types of photocatalytic reactor using a novel Discrete Ordinate Method model recently developed for the open-source computational fluid dynamics (CFD) platform OpenFOAM. The photoreactors represent commonly used geometries and illumination sources in the field of heterogeneous photocatalysis: an annular reactor illuminated by a mercury fluorescent lamp, a tubular reactor coupled to a compound parabolic collector illuminated by sunlight, and a tubular reactor illuminated by LEDs. Simulations were carried out for different photocatalyst concentrations, considering absorption and anisotropic scattering, showing differences smaller than 2.4% with respect to the results obtained by commercial CFD software for systems with isotropic emission, such as fluorescent lamps. Moreover, the model was able to improve the simulation of solar reactors and dramatically outperformed the simulation of LED sources, due to the combined effect of quadrature rotation and cone-limit fitting for cone-shaped sources, as well as a LED-specific power-cosine light distribution. The developed model has been thoroughly validated and is now available to the open-source CFD community. It allows a comprehensive numerical simulation of radiation transport using any type of light source, with applications in numerous engineering fields where optical phenomena affect the performance of the process.

In this study, biochars produced in two different atmospheres were used as catalysts for the valorization of furan, which derives from the hemicellulosic component of waste biomass. The biochars were produced from rice straw via pyrolysis in either an N2 or a CO2 environment (RSB-N2 or RSB-CO2) to modify their surface area and porosity. The biochars were then employed as a catalyst to support a bifunctional Ru–ReOx catalyst. The biochar-supported Ru–ReOx catalysts (Ru–ReOx/RSB) were compared to a conventional activated charcoal (AC)-supported Ru–ReOx catalyst (Ru–ReOx/AC). The biochar-supported catalysts exhibited differences in reducibility and contained a different form of Re species compared to the AC-supported catalyst, which was attributed to the presence of alkali metal (e.g., potassium) in the biochar catalysts. The reducibility and metal dispersion on the support were also strongly associated with the atmosphere under which the biochar was produced. In particular, the Ru–ReOx/RSB-CO2 catalyst consumed 24% more hydrogen than did the Ru–ReOx/RSB-N2 catalyst within a temperature range of 250 to 560 °C. The biochar-supported catalysts had 12 times fewer surface metal sites than did the AC-supported catalyst due to their lower surface area. The reaction rate on a per-site basis for the conversion of furan to tetrahydrofuran and 1,4-butanediol was also measured for the catalysts. The Ru–ReOx/RSB-N2 catalyst was twice as active as the Ru–ReOx/RSB-CO2 catalyst and three times more active than the Ru–ReOx/AC catalyst. This study thus proposes a straightforward strategy for modifying the catalytic properties of biochar catalysts and suggests a new application of biochar in the production of value-added chemicals from biomass and waste. The results also highlight the potential of biochar as a replacement for conventional catalysts in biorefineries.

The supercapacitive performance of two-dimensional (2D) MoS2 nanomaterials strongly depends on the interlayer spacing and edge orientation, which remains a formidable challenge. Herein, we demonstrate a sheet-on-sheet 2D heterostructure with edge-terminated and interlayer-expanded MoS2 few-layered nanosheets on graphene. The preferential (002) edge orientation with an expanded interlayer spacing of 0.98 nm enables easy insertion of ions into the MoS2 nanosheets. The intimate connection with conductive graphene further expedites the electrochemical kinetics by promoting electron/ion transport and structural stability. As a result, the MoS2@graphene nanoarchitecture can deliver a high specific capacitance of 428 F g-1 at 1 A g-1 along with superior rate and long-term durability, which is among the best performance reported so far. The present work highlights the importance of engineering edge-oriented and interlayer-expanded 2D materials for their promising use toward high-performance supercapacitors.

Luminescent materials, particularly those with tunable wavelengths, are gaining considerable attention owing to their advanced applications in optoelectronic devices, fluorescent probes and sensors etc. Among all species studied, luminogens without typical chromophores have been gaining increasing attention. The related studies have been mainly focused on polymers with functional groups, such as aliphatic tertiary amine, carbonyl, ester, hydroxyl, amide, imide etc. Here we report a new type of nonconventional fluorescent emitter, fully water-soluble aliphatic amide salt. By simply blending methanol solution of ethylene diamine with that of succinic acid, the aliphatic amide salt (PA24S) was precipitated out, and identified through a series of advanced testing. Both the salt PA24S and the polyamide showed fluorescent emission as solid powders and in their solutions. The emission behavior of PA24S was studied with regard to concentration, pH, temperature and non-solvent fraction. It was concluded that the emission was owing to the formation of molecule clusters, and confirmed by UV-vis absorption, cluster size measurement and NMR test. It was also demonstrated that Cu2+ was an effective quenching agent with good selectivity. The cytotoxicity assay demonstrated that PA24S was non-toxic to HeLa cell, and suitable for cell imaging. Combined with selective quenching of Cu2+, PA24S is successfully used for Cu2+ detection and monitoring. This work provides therefore a novel type of luminogen of great potential applications in biological fields, featured by its easiness to make, high water solubility and broad emission in dilute solution and at solid state.

The novel structure of electrode materials with high conductivity, large specific surface area and ultra-high energy density is urgently needed to achieve high performance energy storage. Here, a novel hierarchical CoFe2Se4@CoFe2O4 and CoFe2S4@CoFe2O4 core-shell nanoboxes electrode arrays with uniform size and morphology have been successfully deposited on nickel foam through a mild two-step hydrothermal method, which have been further developed as binder-free electrode materials for asymmetric supercapacitors, because of the core-shell structural advantage and multifunctionality of the CoFe2Se4@CoFe2O4 and CoFe2S4@CoFe2O4 nanoboxes. Moreover, the CoFe2Se4@CoFe2O4 electrode acquires an exceptional specific capacitance of 2040.8 F g−1 at 1 A g−1 and excellent rate performance, which is superior to other ternary transition metal sulfides. An asymmetric device with carbon nanotubes as negative electrode, CoFe2Se4@CoFe2O4 as positive electrode and 3M KOH as electrolyte also demonstrates a wide voltage of 1.6 V, a desirable specific capacitance (463.27 F g−1 at 1 A g−1), and a higher energy density of 164.72 Wh kg−1 (at 508 W kg−1) than other reports. Meanwhile, the CoFe2Se4@CoFe2O4//CNTs asymmetric supercapacitor can drive the toy car more than 15 m, indicating the CoFe2Se4@CoFe2O4 electrode own powerful energy storage capacity and application value.

Kinetic hydrate inhibitors (KHIs) are polymeric based chemicals that delay the nucleation and/or suppress the growth rate of gas hydrate crystals. While KHIs have been used successfully to mitigate hydrate blockage risk during oil and gas production, the mechanisms by which they function remain unclear. In this work, multiple high-pressure stirred automated lag time apparatus (HPS-ALTA) were used to investigate the impact of a KHI on the subcooling formation probability distributions of methane hydrates and the subsequent initial growth rates. Over 3000 hydrate formation events were measured around 12 MPa using seven independent HPS-ALTA cells with KHI concentrations of up to 3 wt% in water. The addition of KHI made hydrate formation much less stochastic: significant reductions occurred in both the width of the formation probability distribution for a given cell, and in the offsets between distributions measured with different cells. Average initial hydrate growth rates were reduced by approximately by a factor of 5 as KHI concentration increased, even though the average driving force (subcooling) increased by a factor of up to 3. However, above a KHI concentration of 0.3 wt%, a diminishing return was observed in both the nucleation delay and growth rate suppression. A Classical Nucleation Theory (CNT) framework was applied to investigate whether polymer adsorption onto active nucleation sites could explain the observed delay in formation onset. However, the CNT kinetic parameter extracted from the measured formation probability data increased with concentration, which is opposite to the dependence predicted by the polymer-adsorption model of nucleation suppression by KHIs.

Recovery of antimony (Sb) from wastewater is desired. Deposition of Sb(III) to metal Sb can occur via cathodic reduction, which is limited for Sb(V) reduction. Herein, a UV/sulfite-assisted electrodeposition (UV/sulfite/E) system was developed for the recovery of Sb(V) as metal Sb. The hydrated electron (eaq-) generated from UV/sulfite process reduced Sb(V) to Sb(III), which was simultaneously reduced to metal Sb via cathodic reduction. Results indicated that as high as 95% of Sb(V) with a concentration of 50 mg/L can be deposited onto the cathode as metal Sb within 6 h. The reduction of Sb(V) to Sb(III) by eaq- was confirmed by laser flash photolysis tests. More importantly, the OH- generated at cathode increased the pH of the UV/sulfite/E system and enabled the eaq- generation even at pH = 4, which was beneficial for Sb(V) reduction at a wide pH range. The optimal conditions for Sb(V) recovery were found to be at a sulfite concentration of 10 mM and an applied potential of -1.2 V (vs. SCE). The recovery of Sb(V) from practical Sb-containing wastewater was finally carried out and the results indicated that more than 60% of Sb was recovered as metal Sb.

The performance of the MIL-101(Cr) loaded with cuprous oxide (Cu2O) nanoparticles was evaluated in both equilibrium and kinetic conditions for adsorption of propane and propylene via volumetric method. The single-component adsorption isotherms were measured at temperatures of 303, 323, 343 and 363 K and pressures up to 400 kPa. To correlate the experimental isotherm data points, temperature-dependent Sips model was applied, which exhibited high accuracy of prediction. The synthesized samples were characterized by XRD, BET, FE-SEM, EDS mapping and TEM techniques. The binary mixture adsorption behavior and selectivity of propane/propylene were calculated by using the ideal adsorbed solution theory (IAST). Obtained results showed that by increasing the loading of Cu2O nanoparticles up to 15 wt.%, the propylene selectivity of MIL-101(Cr) was enhanced from 1.5 to 12.2 at 100 kPa and 303 K. Moreover, the optimum performance in terms of both adsorption capacity and selectivity was achieved using 12%[email protected](Cr) sample. Fast diffusion of the adsorbates, obtained by accurate fitting of the isothermal micropore model to the uptake curves data, along with reusability suggest the 12%[email protected](Cr) as a promising adsorbent for effective separation of propane/propylene mixture.