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[Display omitted] Fe, N atoms deposited on porous biochar (Fe-N@BC) composites were synthesized and employed as an efficient catalyst for organic pollutant removal and CrVI reduction. Naturally abundant, renewable and N -rich pomelo peel as a carbon and nitrogen source and unsubstituted phthalocyanine/iron phthalocyanine complexes as a Fe and nitrogen resource were used to develop the Fe-N@BC via a carbonization process. It is found that Fe-N@BC hybrids have homogeneous dispersion of Fe and N atoms on 3D hierarchically porous biochar, which significantly improves the performance toward the detoxification of organic pollutants using peroxymonosulfate as an oxidant, as well as the reduction of hexavalent chromium by formic acid as a reductant. Furthermore, the effects of Fe loading and pyrolytic temperature on catalysis were comprehensively analyzed and optimized. The excellent activity of Fe-N@BC in acid media can be attributed to the high dispersion of Fe species, high content of doped nitrogen as well as hierarchical micro-mesopores, which induce to expose more active sites for catalysis. Owing to the structure-enabled acidic stability, Fe-N@BC efficiently retains its activity as well as its structural stability after several cycles of reactions. This work provides a new approach to construct Fe, N -doped biochar as an effective catalyst for the detoxification of organic and inorganic pollutants. [ABSTRACT FROM AUTHOR]

[Display omitted] • The continuously welded 2D nano-networks were constructed based on hierarchical phase separation. • The impact of the polymer concentrations on the phase behavior in the ternary system was investigated. • The synergistic effect of sieving and adhesion was used to capture the PM. • The interaction between PM and PVB nanowires was proposed. • The spider web-inspired membrane shows excellent air filtration performance and stable long-term recycling capacity. Air pollution has garnered significant worldwide attention; however, the existing air filtration materials still suffer from issues related to monotonous structure and the inherent trade-off between PM rejection and air permeability. Herein, a spider web-inspired composite membrane with continuous monolayer structured 2D nano-networks tightly welded on nanofibers in the electrospun membrane scaffold is designed via a hierarchical phase separation strategy. The resultant biomimetic hierarchical-structured membranes possess the integrated features of hierarchical multiscale structures of 2D ultrafine networks composed of nanowires with a diameter of 31 nm self-assembled by nanoparticles, exceptional characteristics involving small average aperture, extremely low network thickness, high porosity and promising pore channel connectivity, combined with rich surface polar functional groups (3.02D dipole moment). Consequently, the composite membrane exhibits a high PM 0.3 capture efficiency of 99.6 % and low pressure drop of 58.8 Pa, less than 0.06 % of atmosphere pressure, with outstanding long-term PM 2.5 recycling filtration performance. The hierarchical phase separation–driven 2D nano-networks construction strategy, by virtue of their feasibility and tunability, holds great promise for widespread application across diverse membrane-related domains for air filtration. [ABSTRACT FROM AUTHOR]

Polymersomes are hollow spheres self-assembled from amphiphilic block copolymers of certain molecular architecture. Whilst they have been widely studied for biomedical applications, relatively few studies have reported their interfacial properties. In particular, lubrication by polymersomes has not been previously reported. Here, interfacial properties of polymersomes self-assembled from poly(butadiene)-poly(ethylene oxide) (PBD-PEO; molecular weight 10,400 g mol −1 ) have been studied at both hydrophilic and hydrophobic surfaces. Their morphology at silica and mica surfaces was imaged with quantitative nanomechanical property mapping atomic force microscopy (QNM AFM), and friction and surface forces they mediate under confinement between two surfaces were studied using colloidal probe AFM (CP-AFM). We find that the polymersomes remained intact but adopted flattened conformation once adsorbed to mica, with a relatively low coverage. However, on silica these polymersomes were unstable, rupturing to form donut shaped residues or patchy bilayers. On a silica surface hydrophobized with a 19 nm polystyrene (PS) film, the polymer vesicles formed a more stable layer with a higher surface coverage as compared to the hydrophilic surface, and the interfacial structure also evolved over time. Moreover, friction was greatly reduced on hydrophobized silica surfaces in the presence of polymersomes, suggesting their potential as effective aqueous lubricants. [ABSTRACT FROM AUTHOR]

Equilibration in adsorbing polymer systems can be very slow, leading to different physical properties at a given condition depending on the pathway that was used to reach this state. Here we explore this phenomenon using a diblock copolymer consisting of a cationic anchor block and a thermoresponsive block of poly(2-isopropyl-2-oxazoline), PIPOZ. We find that at a given temperature different polymer chain densities at the silica surface are achieved depending on the previous temperature history. We explore how this affects surface and friction forces between such layers using the atomic force microscope colloidal probe technique. The surface forces are purely repulsive at temperatures <40 °C. A local force minimum at short separation develops at 40 °C and a strong attraction due to capillary condensation of a polymer-rich phase is observed close to the bulk phase separation temperature. The friction forces decrease in the cooling stage due to rehydration of the PIPOZ chain. A consequence of the adsorption hysteresis is that the friction forces measured at 25 °C are significantly lower after exposure to a temperature of 40 °C than prior to heating, which is due to higher polymer chain density on the surface after heating. [ABSTRACT FROM AUTHOR]

A micro-patterned silicon surface, consisting of depressions with walls having a tilt angle of 30°, was created by photolithography followed by etching. The friction forces in single asperity contact acting between such a surface and an AFM tip was measured in air. This allowed elucidation of the validity of some common friction rules for this particular situation where a small tip traces a surface having roughness features that are significantly larger than the tip itself. The rules that was compared with our data were Amontons’ first rule of friction stating that the friction force should be proportional to the load; Amontons’ third rule stating that the friction force should be independent of sliding speed, and Euler’s rule providing a relation between slope angle and friction coefficient. We found that both nanoscale surface heterogeneities and the μm-sized depressions affect friction forces, and considerable reproducible variations were found along a particular scan line. Nevertheless Amontons’ first rule described average friction forces well. Amontons’ third rule and Euler’s rule were found to be less applicable to our system. [ABSTRACT FROM AUTHOR]

To improve the gel properties of low-sodium tilapia surimi, the effects of microwave-ultrasonic, single microwave, single ultrasonic and traditional water-bath heating treatments on the characteristics of low-sodium tilapia surimi gel in the gel setting stage were investigated in this study. Compared with other treatment groups, the water-bath heating and microwave–ultrasonic-assisted heating (WB-MW/US) + 1.5% NaCl group had higher gel strength (403.30 g cm) and water-holding capacity (87.88%). LF-NMR and CD spectrum analysis indicated that microwave and ultrasonic combination increased the degree of protein cross-linking and moisture proton density. In addition, microwave and ultrasonic combination had minimal effect on the secondary protein structure. WB-MW/US+1.5% NaCl group had more β-sheet (27.80%) and random coil content (22.30%), resulting in a uniform and dense spatial network structure of the low-sodium tilapia surimi gel. The results indicated that the microwave-ultrasonic combination treatment could be used as an efficient strategy for the production of new energy, low-sodium surimi gel products. • A new microwave-ultrasonic assisted gel setting stage method was developed. • Microwave-ultrasonic combination could improve physicochemical properties of surimi gel. • Microwave-ultrasonic combination promoted the transformation of protein secondary structure. • Microwave-ultrasonic combination gives low-sodium tilapia surimi gel the highest degree of bound moisture. • Microwave-ultrasonic combination could strengthen protein network structure. [ABSTRACT FROM AUTHOR]

Pre-adsorbed branched brush layers were formed on silica surfaces by adsorption of a diblock copolymer consisting of a linear cationic block and an uncharged bottle-brush block. The charge of the silica surface was found to affect the adsorption, with lower amounts of the cationic polyelectrolyte depositing on less charged silica. Cleaning under basic conditions rendered surfaces more negatively charged (more negative zeta-potential) than acid cleaning and was therefore used to increase polyelectrolyte adsorption. The structure of adsorbed layers of the diblock copolymer was as determined by neutron reflectometry found to be about 70 nm thick and very water rich (97%). Interactions between the anionic surfactant sodium dodecylsulfate (SDS) and such pre-adsorbed diblock polymer layers were studied by neutron reflectometry and by optical reflectometry. Optical reflectometry was also used for deducing interactions between the individual blocks of the diblock copolymer and SDS at the silica/aqueous interface. We find that SDS is readily incorporated in the diblock copolymer layer at low SDS concentrations, and preferentially co-localized with the cationic block of the polymer next to the silica surface. At higher SDS concentrations some desorption of polyelectrolyte/surfactant complexes takes place. [ABSTRACT FROM AUTHOR]

Although nitrogen (N) transformations have been widely studied under oxic or anoxic condition, few studies have been carried out to analyze the transformation accompanied with NO 2 −-N accumulation. Particularly, the control of mixed N species in N-transformation remains unclear in an oxic-anoxic transition zone (OATZ), a unique and ubiquitous redox environment. To bridge the gap, in this study, OATZ microcosms were simulated by surface water and sediments of a shallow lake. The N-transformation processes and rates at different NH 4 +-N/NO 3 −-N ratios, and NO 2 −-N accumulations in these processes were evaluated. N-transformation process exhibited a turning point. Simultaneous nitrification and denitrification occurred in its early stage (first 10 days, dissolved oxygen (DO) ≥ 2 mg/L) and then denitrification dominated (after 10 days, DO < 2 mg/L), which were not greatly affected by the NH 4 +-N/NO 3 −-N ratio, on the contrary, the transformation rates of NH 4 +-N and NO 3 −-N were distinctly affected. The NH 4 +-N transformation rates were positively correlated with the NH 4 +-N/NO 3 −-N ratio. The highest NO 3 −-N transformation rate was observed at an NH 4 +-N/NO 3 −-N ratio of 1:1 with organic carbon/NO 3 −-N of 3.09. The NO 2 −-N accumulation, which increased with the decrease in NH 4 +-N/NO 3 −-N ratio, was also controlled by organic carbon concentration and type. The peak concentration of NO 2 −-N accumulation occurred only when the NO 3 −-N transformation rate was particularly low. Thus, NO 2 −-N accumulation may be reduced by adjusting the control parameters related to N and organic carbon sources, which enhances the theoretical insights for N-polluted aquatic ecosystem bioremediation. • Nitrogen transformation in the oxic-anoxic transition zone was investigated. • Nitrification-denitrification occurred in early days, then denitrification dominated. • NH 4 +-N/NO 3 −-N ratio controlled their transformation rates and NO 2 −-N accumulation. • NO 2 −-N accumulation peaked when NO 3 −-N transformation rate was rather low. [ABSTRACT FROM AUTHOR]

Cancer cells frequently develop resistance to chemotherapeutic therapies and targeted drugs, which has been a significant challenge in cancer management. With the growing advances in technologies in isolation and identification of natural products, the potential of natural products in combating cancer multidrug resistance has received substantial attention. Importantly, natural products can impact multiple targets, which can be valuable in overcoming drug resistance from different perspectives. In the current review, we will describe the well-established mechanisms underlying multidrug resistance, and introduce natural products that could target these multidrug resistant mechanisms. Specifically, we will discuss natural compounds such as curcumin, resveratrol, baicalein, chrysin and more, and their potential roles in combating multidrug resistance. This review article aims to provide a systematic summary of recent advances of natural products in combating cancer drug resistance, and will provide rationales for novel drug discovery. [Display omitted] [ABSTRACT FROM AUTHOR]

Hydrothermal aqueous phase (HAP) contains abundant organics and nutrients, which have potential to partially replace chemical fertilizers for enhancing plant growth and soil quality. However, the underlying reasons for low available nitrogen (N) and high N loss in dryland soil remain unclear. A cultivation experiment was conducted using HAP or urea to supply 160 mg N kg−1 in dryland soil. The dynamic changes of soil organic matters (SOMs), pH, N forms, and N cycling genes were investigated. Results showed that SOMs from HAP stimulated urease activity and ureC , which enhanced ammonification in turn. The high-molecular-weight SOMs relatively increased during 5–30 d and then biodegraded during 30–90 d, which SUV 254 changed from 0.51 to 1.47 to 0.29 L−1 m−1. This affected ureC that changed from 5.58 to 5.34 to 5.75 lg copies g−1. Relative to urea, addition HAP enhanced ON mineralization by 8.40 times during 30–90 d due to higher ureC. It decreased NO 3 –N by 65.35%–77.32% but increased AOB and AOA by 0.25 and 0.90 lg copies g−1 at 5 d and 90 d, respectively. It little affected nirK and increased nosZ by 0.41 lg copies g−1 at 90 d. It increased N loss by 4.59 times. The soil pH for HAP was higher than that for urea after 11 d. The comprehensive effects of high SOMs and pH, including ammonification enhancement and nitrification activity inhibition, were the primary causes of high N loss. The core idea for developing high-efficiency HAP fertilizer is to moderately inhibit ammonification and promote nitrification. [Display omitted] • HAP relative to urea increased N loss by 4.59 times during 90 d cultivation. • HAP increased ureC during 30–90 d when high molecular weight DOMs biodegraded. • HAP increased AOA + AOB by 0.95 lg copies g−1 but decreased 65.35%–77.32% NO 3 –N. • HAP little changed nirK and increased nosZ by 0.41 lg copies g−1. • High soil pH and SOMs reasoned from HAP were the main reasons. [ABSTRACT FROM AUTHOR]

A Ru-Mo bimetallic catalyst was developed by decorating Ru NPs with mononuclear Mo5+Ox for the selective hydrodeoxygenation (HDO) of amides to amines, where the C O bond of amide is selectively activated on the low-coordinated mononuclear Mo5+Ox sites and the HDO reaction proceeds at the interface of Ru and Mo5+Ox. [Display omitted] • A highly active, selective and stable RuMo/SiO 2 catalyst with Ru nanoparticles of ∼ 2 nm decorated with mononuclear Mo5+Ox has been developed for the HDO of primary amides to amines. • The catalytic performance relies critically on the Mo/Ru ratio, and high activity and selectivity are only achieved when Mo/Ru ratio is smaller than 0.12 where mononuclear Mo5+Ox dominates. • The characterizations and reaction kinetics show that the C O bond of the amide is activated on the low-coordinated mononuclear Mo5+Ox species and the reaction proceeds at the MoRu interface. The selective hydrodeoxygenation (HDO) of amides is a key methodology to producing amines, yet it remains a great challenge due to the highly stable amide molecular structure. In this study a series of 2Ru x Mo/SiO 2 (x = 0 ∼ 3) catalysts were prepared with sequential impregnation method followed by reduction. The reaction tests showed that the target amine yield presented a volcano-shape dependence on the Mo content, and reached the highest value at the Mo content of 0.2 wt% which corresponded to a Mo/Ru atomic ratio of 0.11 and a Mo surface density of 0.08. By contrast, a higher Mo content resulted in dramatic decrease in both activity and selectivity. By using HAADF-STEM, X-ray absorption spectroscopy (XAS), H 2 -TPR and CO-chemisorption, the structure of the best-performance 2Ru0.2Mo/SiO 2 catalyst was identified as Ru NPs of ∼ 2 nm decorated with mononuclear Mo5+O x species, which was in contrast with the polymeric MoO 2 -like species partially covering the Ru surface for the 2Ru3Mo/SiO 2. Kinetic studies revealed that the reaction order with respect to CyCONH 2 was 1.2, −0.1 and −0.5 over the 2Ru/SiO 2 , 2Ru0.2Mo/SiO 2 and 2Ru3Mo/SiO 2 , respectively, which indicated amide was selectively activated on the low-coordinated Mo5+O x sites while H 2 was activated on the Ru sites and the reaction proceeded at the Mo-Ru interface. The turnover frequency based on interfacial Ru-Mo sites reached 407.8 h−1, which was more than twofold higher than that of Ru-W system (175.6 h−1) we previously reported. [ABSTRACT FROM AUTHOR]

Antibiotic resistance genes (ARGs) are emerging microbial pollutants that are regulated by many factors and pose potential threats to aquatic environments. In this study, we used network analysis, correlation analysis, and constructed models based on metagenomic sequencing results to explore the spatial patterns, impact mechanisms, transmission risks and differences in ARGs in the water and sediment of the Weihe River Basin. The findings revealed notable disparities in ARGs, mobile genetic elements (MGEs), and bacterial communities. In the sediment, the abundance of ARGs was considerably greater than that in water. Moreover, the percentage of ARGs shared by the two components reached a value of 85.8%. Through network analysis, it was determined that the presence of 16 MGEs and 20 bacterial phyla was strongly associated with ARGs (R2 > 0.7, P < 0.05). The Mantel test showed that abiotic factors including DO, pH, nutrients, and heavy metals played important roles in the distribution of ARGs (P < 0.05). A structural equation model revealed that the key factors influencing the distribution of ARGs in water were bacterial diversity and environmental parameters (standardized effects of −0.730 and −0.667), and those in sediment were bacterial diversity and MGEs (standardized effects of −0.751 and 0.851). Neutral modeling indicated that deterministic processes played an important role in the assembly of ARGs in the water of the Weihe River Basin, and stochastic processes were dominant in the sediment. There was a highly significant positive linear correlation between ARGs and pathogens, and there was more complex co-occurrence in the water than in the sediment (R2 > 0.9, P < 0.05), with stronger migration and transmission occurring. Exploring ARGs in large-scale watersheds is immensely important for elucidating their traits and transmission mechanisms and consequently paving the way for the formulation of efficient strategies to mitigate resistance threats. • ARGs exhibit different distribution patterns in water and sediment. • Deterministic processes are important in the assembly of ARGs in water, and stochastic processes are dominant in sediment. • ARGs are affected by bacterial diversity and environmental factors in water, and bacterial diversity and MGEs in sediment. • DO, pH, nutrients, and heavy metals play important roles in the distribution of ARGs. • ARGs are more intensely migrating and spreading to pathogens in water than sediment. [ABSTRACT FROM AUTHOR]

Phospholipids fulfill an important role in joint lubrication. They, together with hyaluronan and glycoproteins, are the biolubricants that sustain low friction between cartilage surfaces bathed in synovial fluid. In this work we have investigated how the friction force and load bearing capacity of 1,2-dipalmitoyl-sn-glycero-3-phosphocholine (DPPC) bilayers on silica surfaces are affected by temperature, covering the temperature range 25–52 °C. Friction forces have been determined utilizing the AFM colloidal probe technique, which showed that DPPC bilayers are able to provide low friction forces over the whole temperature interval. However, the load bearing capacity is improved at higher temperatures. We interpret this finding as being a consequence of lower rigidity and higher self-healing capacity of the DPPC bilayer in the liquid disordered state compared to the gel state. The corresponding structure of solid supported DPPC bilayers at the silica–liquid interface has been followed using X-ray reflectivity measurements, which suggests that the DPPC bilayer is in the gel phase at 25 °C and 39 °C and in the liquid disordered state at 55 °C. Well-defined bilayer structures were observed for both phases. The deposited DPPC bilayers were also imaged using AFM PeakForce Tapping mode, and these measurements indicated a less homogeneous layer at temperatures below 37 °C. [ABSTRACT FROM AUTHOR]

The effect of mix-cultured aerobic denitrifying microorganisms on the water remediation has been extensively explored, but little is known about the performance of mix-cultured low efficiency fungi on denitrification. In this study, two kinds of aerobic denitrifying fungi (Trichoderma afroharzianum H1 and Aspergillus niger C1) were isolated from reservoirs, improved the capacity by mix-cultured. The results showed a difference between northern and southern reservoirs, the dominants of genera were Cystobasidium and Acremonium. The removals of total nitrogen (TN) was 12.00%, 7.53% and 69.33% in Trichoderma afroharzianum H1, Aspergillus niger C1 and mix-cultured (C1 and H1) under the denitrification medium. The contents of ATP and electron transport system activity in mix-cultured amendment were increased by 42.54% and 67.52%, 1.72 and 2.91 times, respectively. Besides, the raw water experiment indicated that TN removals were 24.05%, 12.66% and 73.42% in Trichoderma afroharzianum H1, Aspergillus niger C1 and mix-cultured. The removals of dissolved organic carbon in mix-cultured were increased 35.02% and 50.46% compared to Trichoderma afroharzianum H1 and Aspergillus niger C1. Therefore, mix-cultured of two low efficiency aerobic denitrifying fungi has been considered as a novelty perspective for mitigation of drinking water source. • Trichoderma afroharzianum H1 and Aspergillus niger C1 were isolated from reservoirs. • Mix-cultured of two fungi improved the performance of aerobic denitrifying. • Mix-cultured could remove 69% total nitrogen and 93% of dissolved organic carbon. • The ATP and electron transport system activity were increased by mix-cultured. • Mix-cultured exhibited excellent nitrogen and carbon removal ability in raw water. [ABSTRACT FROM AUTHOR]

Flooding undermines the functionality of road links, leading to commute disruption, such as increased commuting time and immobility. Therefore, identifying the critical roads under different flood scenarios is of great significance for transportation planning to minimize flood risk. Previous studies on the road criticality under pluvial floods have focused on mostly structural characteristics of the roads, lacking the quantification of the flood impact on traffic. We employed an integrated framework coupling pluvial flood modeling with commute simulation to assess the criticality of flooded road links under three scenarios (10, 30, and 50 year floods). The output of the flood modeling was used to reconstruct the road network. The routes of each individual commuter under a business as usual (BAU) scenario and three flood scenarios were obtained from the commute simulation. As the flood return period increased, the distribution of traffic flow became more uneven. The road criticality assessment revealed that greater flood impact on roads was closely related to the proximity of water bodies, low-lying topography, and greater commute demands of the region and provided evidence to prioritize locations for interventions. This study helps understand the resilience of transportation systems during floods, thereby enabling practitioners to design effective strategic plans in terms of emergency response, risk management, and urban planning. • Developed the road criticality indicators to characterize the impact of road disruption on commutes during floods. • The distribution of traffic flow became more uneven as the flood return period increased. • The causes of impassable roads were spatially heterogeneous. • The road criticality indicators provided ground for prioritizing interventions. [ABSTRACT FROM AUTHOR]

Ideal breathable and waterproof materials contain two key elements: hydrophobic matrix and small pore size. Current high-performing breathable waterproof membranes usually employ fluorinated materials to construct hydrophobic surface, which possess alarming potential environmental hazards. Fluorine-free waterproof agents through coating treatment to obtain hydrophobicity suffer from complicated fabrication process and poor durability. Hence, non-fluorinated chemicals incorporated into fibers via a facile one-step electrospinning may be an effective approach to attain durable hydrophobic membranes. Poly(methylhydrosiloxane)/polyurethane (PMHS/PU) solution with various PMHS concentration was formulated and electrospun to fibrous membranes, followed by a facile thermal treatment process. A systematic study including morphologies, porous structure, and surface wettability was performed. Breathable waterproof performance and tensile strength were also investigated. Added PMHS imparted mighty hydrophobicity to the membranes with a water contact angle of 130.2°, and the subsequent heat treatment greatly improved waterproofness, meanwhile doubled the tensile strength. The resultant membranes exhibited robust hydrostatic pressure of 54.1 kPa, medium breathability of 9.5 kg m−2 d−1, and excellent stretching stress of 14.1 MPa, which can meet the requirements of general use. The presented strategy on membrane fabrication is feasible and scalable, which may be considered as an effective remedy for environmental protection. [ABSTRACT FROM AUTHOR]

Zinc oxide (ZnO) nanophotocatalyst is a promising candidate for degrading organic pollutants but has an extremely low photocatalytic activity under nature sunlight. In this work, flower-like MoS 2 quantum dots/ZnO (MQ/ZnO) nanospheres with the size of approximately 1.26 μm are prepared at low temperature. The resultant flower-like MQ/ZnO nanospheres displayed higher photocatalytic activity than pure ZnO nanospheres under natural sunlight and without stirring, with the decomposition rate of the MQ/ZnO composites approximately 3.3 times higher than that of the pure ZnO nanospheres. Furthermore, the introduction of MoS 2 QDs endowed ZnO nanospheres with optical memory ability. The enhanced sunlight-driven photocatalytic activity is dependent on the unique electrical properties of MoS 2 QDs and the synergistic effect between ZnO and MoS 2 QDs. [ABSTRACT FROM AUTHOR]

In this study, a novel three-dimensional zinc-based metal-organic framework (Zn-MOF), i.e., {Zn 2 (L) 2 (DMF) 2 H 2 O} n (L = 2,5-bis(phenylamino)-1,4-benzenedicarboxylic acid) was designed and developed under solvothermal condition. As a proof-of-principle, a π-conjugated framework of carboxylate ligand capable of “bottom up” synthesis was integrated with metal ion to construct a novel MOF for sensing applications. As expected, the synthesized Zn-MOF exhibited fluorescence enhancement for cadmium ion (Cd 2+ ) and sensing of nitrobenzene (NB) through fluorescence quenching. The detection limits were calculated to be 0.12 μM for Cd 2+ and 1.19 μg mL −1 for NB based on signal-to-noise ratio of 3:1. Moreover, various techniques and density functional theory investigations verified that the possible sensing mechanisms for Cd 2+ and NB included ion exchange and photoinduced electron transfer, respectively. Finally, their practical applications on real samples also demonstrated that the Zn-MOF-based sensor can be effectively utilized for detection and imaging of Cd 2+ present in the real water samples and living cells. This study may inspire future research and design of target fluorescent MOFs with specific functions. [ABSTRACT FROM AUTHOR]

Fe2O3-assisted pyrolysis has been demonstrated to be a cost-effective thermal desorption (TD) technology. Lurgi-Thyssen dust (LTD) is a type of steel slag waste that contains a large amount of Fe2O3. In this study, to reduce energy consumption, LTD was added to contaminated soil to evaluate the feasibility of enhancing the TD removal efficiency of di-(2-ethylhexyl) phthalate (DEHP). The DEHP removal rate increased by 22.39% after adding 2% LTD at 200 °C for 20 min. Because of the catalytic pyrolysis of LTD, DEHP was pyrolyzed to form three types of short-chain esters: mono-(2-ethylhexyl) phthalate (MEHP), di (2-methylbutyl) ester, and methyl 2-ethylhexyl phthalate. The pyrolysis products of DEHP were less toxic and did not affect soil reuse. When the DEHP removal rate was 87.10%, LTD addition decreased the temperature and residence time of TD and alleviated the effect of TD on the soil physicochemical properties. Additionally, the desorption of DEHP from soil fitted the pseudo-second-order kinetic model well. Thus, the addition of LTD to contaminated soil enhanced the efficiency of TD remediation. Moreover, this study could provide a practical and economical strategy for LTD reuse. • Thermal desorption of di (2-ethylhexyl) phthalate involved volatilization, pyrolysis. • Lurgi-Thyssen dust improved the thermal desorption remediation effect. • The catalysis includes alkyl bond breakage, ester hydrolysis, carboxyl methylation. [ABSTRACT FROM AUTHOR]

Phospholipids and hyaluronan have been implied to fulfil important roles in synovial joint lubrication. Since both components are present in synovial fluid, self-assembly structures formed by them should also be present. We demonstrate by small angle X-ray scattering that hyaluronan associates with the outer shell of dipalmitoylphophatidylcholine (DPPC) vesicles in bulk solution. Further, we follow adsorption to silica from mixed hyaluronan/DPPC vesicle solution by Quartz Crystal Microbalance with Dissipation measurements. Atomic Force Microscope imaging visualises the adsorbed layer structure consisting of non-homogeneous phospholipid bilayer with hyaluronan/DPPC aggregates on top. The presence of these aggregates generates a long-range repulsive surface force as two such surfaces are brought together. However, the aggregates are easily deformed, partly rearranged into multilayer structures and partly removed from between the surfaces under high loads. These layers offer very low friction coefficient (<0.01), high load bearing capacity (≈23 MPa), and self-healing ability. Surface bound DPPC/hyaluronan aggregates provide a means for accumulation of lubricating DPPC molecules on sliding surfaces. [ABSTRACT FROM AUTHOR]

Catalytic hydrogenation of CO 2 to methane was investigated over Ru/rutile TiO 2 , focusing on the influence of the pretreatment temperature on the activity. Rutile TiO 2 stabilized Ru nanoparticles even after pretreatment at 800 °C; therefore it was possible to establish the structure–activity relationship without considering the particle size effect. The CO 2 turnover frequency initially increased with increasing pretreatment temperature from 300 to 800 °C, and reached a maximum value of 1.59 s −1 on Ru/rutile TiO 2 pretreated at 600 °C; it decreased to 1.16 s −1 for the sample pretreated at 800 °C. The characterization results indicated that the activity depended on both the extent of encapsulation of Ru particles by TiO x layers and the number of hydroxyl groups on the TiO x surface. The mechanism of CO 2 methanation was discussed based on in situ diffuse-reflectance infrared Fourier-transform spectroscopy results. [ABSTRACT FROM AUTHOR]

This study aimed to investigate effect of Hong Qu on flavor and quality of Hakka yellow rice wine (Hakka Huangjiu). Volatile components of three kinds of Hakka Huangjiu with or without adding Hong Qu were analyzed by solid phase microextraction-gas chromatography-mass spectrometry. Their non-volatile components were also detected by liquid chromatography quadrupole Orbitrap mass spectrometry (LC-Q-Orbitrap-MS). Results indicated that there were great differences in flavor components among three wines. Among them, the main difference components between traditional Hakka Huangjiu and Hakka Huangjiu without adding Hong Qu were isoamyl alcohol, phenylethanol, isobutyl acetate, isobutyl alcohol, ethyl palmitate and ethyl decanoate. In Hakka Huangjiu, esters were the most volatile components, followed by alcohols, while acids were less. Under NEG and POS modes of LC-Q-Orbitrap-MS, a total of 765 and 1244 components were detected in three kinds of Hakka Huangjiu, respectively. Among 217 kinds of polypeptides detected, the content of 160 kinds of polypeptides in Hakka Huangjiu adding only with Hong Qu was higher than that of traditional Hakka Huangjiu and Hakka Huangjiu without adding Hong Qu. Amino acids and polypeptides contents in Hakka Huangjiu brewed only with Hong Qu and traditional Hakka Huangjiu co-fermented with Hong Qu were relatively high. • Effect of Hong Qu on flavor and quality of Hakka Huangjiu was firstly reported. • Hakka Huangjiu added with Hong Qu had relatively high amino acid and polypeptide. • The tripeptide Gly-Leu-Phe was firstly identified in Hakka Huangjiu by LC-Q-Orbitrap-MS. [ABSTRACT FROM AUTHOR]

The present study investigated the nitrogen removal characteristics and metabolic pathway of bacteria in aquatic ecosystem, with a focus on heterotrophic nitrification and aerobic denitrification. The bacteria demonstrated significant heterotrophic nitrification and aerobic denitrification capacity. The highest ammonium-N, nitrate-N, and nitrite-N removal efficiencies were 95.31 ± 0.11%, 98.91 ± 0.05%, and 98.79 ± 0.09%, respectively. The Monod model was used to estimate the maximum rate of substrate utilization (R mo) and the half-saturation concentration (K s) for the two substrates, i.e., ammonium and nitrate. The kinetic coefficients were 3.34 mg/L/d (R mo) and 30.59 mg/L (K s) for ammonium-N, respectively, and 14.23 mg/L/d (R mo) and 215.24 mg/L (K s) for nitrate-N, respectively. The effects of initial nitrogen (ammonium-N or nitrate-N) concentration, temperature, and dissolved oxygen (DO) on nitrogen removal rate were investigated using response surface methodology (RSM), and the optimal conditions for nitrogen removal were determined. The principal nitrogen removal pathway of the bacteria was proposed as complete heterotrophic nitrification and aerobic denitrification, which was performed by six key genera: Arthrobacter , Pseudomonas , Rhodococcus , Bacillus , Massilia , and Rhizobium. Chryseobacterium and other denitrifying species may also reduce nitrification products (NO X −) via aerobic denitrification. • Heterotrophic nitrification and aerobic denitrification were established. • Monod kinetic coefficients indicated great application potential of the well-cultured sediment. • RSM was a reliable method for determining the optimum point for nitrogen removal. • Complete heterotrophic nitrification and aerobic denitrification was the principle nitrogen removal pathway. [ABSTRACT FROM AUTHOR]