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The aging of microplastics (MPs) is extremely influenced by photochemically-produced reactive intermediates (PPRIs), which are mediated by natural photosensitive substances. Algal extracellular polymeric substances (EPS) can produce PPRIs when exposed to sunlight. Nonetheless, the specific role of EPS in the aging process of MPs remains unclear. This work systematically explored the aging process of polystyrene (PS) MPs in the EPS secreted by Chlorella vulgaris under simulated sunlight irradiation. The results revealed that the existence of EPS accelerated the degradation of PS MPs into particles with sizes less than 1 µm, while also facilitating the formation of hydroxy groups on the surface. The release rate of dissolved organic matter (DOM) from PS MPs was elevated from 0.120 mg·L-1·day-1 to 0.577 mg·L-1·day-1. The primary factor contributing to the elevated levels of DOM was humic acid-like compounds generated through the breakdown of PS. EPS accelerated the aging process of PS MPs by primarily mediating the formation of triplet excited states (3EPS*), singlet oxygen (1O 2), and superoxide radicals (O 2 ∙-), resulting in indirect degradation. 3EPS* was found to have the most substantial impact. This study makes a significant contribution to advance understanding of the environmental fate of MPs in aquatic environments impacted by algal blooms. [Display omitted] • Algae EPS greatly enhanced the microplastic (MP) aging under simulated sunlight. • Photoaging of MP induced by EPS led to changes in MP physicochemical properties. • 3EPS*, 1O 2 , and O 2 ∙- mediated by EPS contributed to the MP aging. • 3EPS* was the dominant specie for accelerating the aging process of MPs. [ABSTRACT FROM AUTHOR]

Microplastics (MPs) are considered to influence the bioavailability of heavy metals through direct adsorption, but this neglects the distribution of heavy metal chemical speciation indirectly influenced by MPs by altering geochemical properties. The present study aims to explore the link between the fractionation distribution of cadmium (Cd2+) and changes in geochemical properties in sediments induced by polyethylene terephthalate microplastics (PET-MPs). The PET-MPs reduced the acid-soluble fraction of Cd2+ in sediments and increased its organically bound fraction. In addition, the concentration of bioavailable Cd2+ in the sediment decreased by 4.09–25.96 % with increasing PET-MPs doses and aging. Whereas the thermal aging of PET-MPs led to a decrease in the molar ratio of oxygen-containing functional groups and the BET surface area, which is not favorable for improving the adsorption capacity of PET-MPs. On the other hand, the correlation analysis demonstrated the key role of PET-MPs in increasing the content of sediment organic matter and its humification level, which indirectly led to a decrease in Cd2+ bioavailability. The microbial analysis demonstrated that PET-MPs increase the relative abundances of Chloroflexi , hexokinase, and 6-phosphofructose kinase in sediments, thereby increasing the humification level of sediment organic matter. The present study provides a new perspective for understanding the environmental risks of MPs-altered heavy metals. [Display omitted] • MPs transformed Cd2+ into less bioavailable fractions in sediments. • Thermal aging enhanced MPs' inhibitory effect on Cd2+ bioavailability in sediments. • MPs reduced Cd2+ bioavailability by raising sediment OM and humification levels. • MPs-induced changes in sediment geochemical properties affect Cd2+ bioavailability. [ABSTRACT FROM AUTHOR]

Herein, ternary metal-organic frameworks (MOFs)-derived MnCoFeO with different levels of oxygen vacancies (O v) were designed by adjusting the doping amount of Mn and employed to activate peroxymonosulfate (PMS) for sulfamethoxazole (SMX) degradation. The MnCoFeO-2 with the largest O v content exhibited the highest SMX degradation efficacy. Almost 100% of SMX was removed within 5 min using the MnCoFeO-2/PMS system. The reaction rate constant (k obs) was 1.7321 min−1, which was 4.1 times that of CoFeO (0.4195 min−1). Both the SO 4 •− and 1O 2 were the dominant reactive oxygen species. Significantly, the relationship among O v , radical pathways, and non-radical pathways was explored for the first time. The results showed that O v could regulate the radical pathways by promoting the adsorption of PMS onto MnCoFeO-2. O v was positively correlated with 1O 2 (P < 0.05) and facilitated the direct electron transfer. The superior catalytic activity of MnCoFeO was attributed to the Fe, Co, Mn active sites, Lewis basic sites and O v in MnCoFeO. Mn(II) not only contributed to the formation of O v , but also facilitated the reduction of Fe(III). Additionally, O v was mainly concentrated near the low-valent metal ions, thus the synergistic effect between the metal active sites and O v promoted the activation of PMS. [Display omitted] • Ternary MOFs-derived MnCoFeO with different levels of O v were synthesized. • The amount of O v in the catalysts was adjusted by changing the Mn doping content. • MnCoFeO-2 with the largest amount of O v gave the fastest SMX degradation kinetics. • Relationship among O v , radicals and non-radicals was explored for the first time. • Synergistic effect between metal active sites and O v promoted the PMS activation. [ABSTRACT FROM AUTHOR]

Metal pollution is a worldwide concern and may pose risks to aquatic organisms, communities, and ecosystems. The toxic effects of metals at the organism level are relatively clear. However, their impacts at the community level are still poorly understood, especially with concurred eutrophication in surface water. In the present study, the effects of Cd on the plankton community structure and function under varying nutrient conditions were evaluated using a microcosm study. The employed concentrations of Cd and nutrient were based on the values currently measured in the freshwater ecosystem. For the plankton structure, our results showed that the Chl a concentration, the abundances of total phytoplankton, Cyanophyta, and Chlorophyta, and the abundance of Copepoda decreased by Cd consistently. The Cyanophyta Oscillatoria tenuis and Copepoda nauplius were the most sensitive species to Cd in the phytoplankton and zooplankton community, respectively. For the community effects, we found the inhibitory effects of Cd on the photosystem II (PSII) activity of phytoplankton community because of the consistent decrease in the chlorophyll fluorescence parameters (F v / F m , Y (Ⅱ), and ETR). Furthermore, the reductions of DOC and pH by Cd were only found in the high nutrient condition, which indicated that the toxic effects of Cd on the community structure and community metabolites were aggravated by the increased nutrient. This study emphasizes the importance of considering nutrient conditions when assessing the metal ecotoxicological effects at environmentally relevant concentrations. [Display omitted] • The toxicity of Cd under different nutrient conditions at environmental concentrations was characterized at community level. • The direct and indirect effects of Cd were quantitative analyzed. • The nutrient can magnify the Cd effects on the plankton community structure and metabolites. [ABSTRACT FROM AUTHOR]

The N-doped three-dimensional (3D) needle bridge connection core-shell structure N-CoS 2 @Co 3 O 4 synthesized in this work was prepared by simple hydrothermal and high-temperature vulcanization methods. The optimized N-CoS 2 @Co 3 O 4 -2 composite response to NO 2 is 62.3–100 ppm, a response time of 1.3 s, the recovery time of 17.98 s, the detection limit of 5 ppb and stability of as long as 10 weeks at room temperature (RT). Its excellent NO 2 sensing performance is attributed to the unique porous and bridge connection core-shell structure of the N-CoS 2 @Co 3 O 4 -2 with high specific surface area, interconnected internal channels, abundant exposed S edge active sites, and high catalytic performance promoted by N-doping. This simple manufacturing method of high-performance sensing materials paves the way for the design of N-doped bridge connection core–shell structures. [Display omitted] • N-doped three-dimensional needle bridge connection core-shell structure N-CoS 2 @Co 3 O 4 were synthesized by a simple strategy. • Unique porous and bridge connection core-shell structure provides the pathway for electron transfer and target gas diffusion. • The co-doping of S and N leads to the change of the charge density, which further increases the active sites. • Fast response and recovery time (1.3 s, 17.98 s), low detection limit (5 ppb). • The sensor maintains a good stability in the whole 10 weeks. [ABSTRACT FROM AUTHOR]

Abstract: In this study, nanoscale Fe0 was immobilized in and on poly(vinyl alcohol) (PVA) microspheres by the inverse suspension crosslinked method. Two different sizes of Fe0/PVA microspheres were synthesized in the presence and absence of dispersant. The chelating action between Fe2+ and PVA was identified by Fourier transform infrared and X-ray photoelectron spectroscopy. The morphology and distribution of the obtained Fe0/PVA microspheres were characterized by environmental scanning electron microscope, energy-dispersive X-ray spectrometry, and X-ray diffraction. Nanoscale Fe0 particles were mostly dispersed over the surface of the microspheres. They were distributed more homogeneously on the surfaces of Fe0/PVA microspheres with diameter of 600–700μm than those with diameter of 10–12μm. The nitrobenzene (NB) reduction reactions followed pseudo-first-order kinetics. The normalized surface rate constants (k SA) values were determined to be 0.162Lh−1 m−2 for L-Fe0/PVA microspheres, 0.098Lh−1 m−2 for S-Fe0/PVA microspheres, and 0.023Lh−1 m−2 for nanoscale Fe0 particles. Furthermore, with the analysis of the products by GC/MS, possible reductive pathways of NB by Fe0/PVA microspheres were suggested. The recovery rates of iron in microspheres were determined to be 81.17% for large Fe0/PVA and 60.31% for small Fe0/PVA. [Copyright &y& Elsevier]

Simultaneous construction of porous and hollow adsorbent, especially from gas-in-water Pickering emulsion (PE) reactor, is vital for improving mass transfer kinetics and uptake amount. Inspired by the formation process of stalagmites in karst cave, amino and amidoxime bifunctionalized lotus root-type microsphere with porous surface (NH 2 @AO-PLRMS) is prepared by the silica nanoparticles (SPs)-stabilized CO 2 -in-water Pickering emulsion reactor and subsequent two-step grafting polymerization. The important roles of SPs acting as Pickering emulsifier, surface pore-forming agent, and adjusting internal lotus root structure are confirmed. Lotus root-type pores are dependent on the interface intensity and the permeability for compressed CO 2 bubbles in PE droplets. Benefitting from the lotus root-type structure and abundant affinity sites, the maximum uranium adsorption capacity of NH 2 @AO-PLRMS is 1214.5 mg·g−1 at 298 k, and an ultrafast uptake process can be achieved in the first 30 min. Both thermodynamic and kinetic studies indicate a spontaneous, entropy increased, and exothermic chemisorption process, and the synergies of amidoxime and amino groups can enhance the adsorption selectivity. Remarkably, NH 2 @AO-PLRMS displays a high uranium adsorption capacity and desorption efficiency after seven cycles. These findings provide a way to obtain adsorbents with enhanced uranium extraction performance from gas-in-water PE reactor. [Display omitted] • A lotus root-type sorbent with porous surface was prepared for the first time. • NH 2 @AO-PLRMS shows rapid uptake kinetics and remarkable selectivity for U(VI)-extract. • Two-step grafting polymerization endows NH 2 @AO-PLRMS with high affinity sites. • The synergies of amidoxime and amino groups is the main adsorption mechanism. [ABSTRACT FROM AUTHOR]

Via enlarging the specific surface area of sludge biochar to enhance the close contact of multiple reactants may be a simple route to improve the catalytic performance with reduced dosage of biochar and oxidant, benefitting for cost-effectiveness and eco-friendliness. Herein, PS activation ability of a reported sludge-derived biochar adsorbent was investigated. 80% TOC of 100 mL 10 mg/L BPA was removed within 40 min by 7 mg biochar and 0.5 mM PS mixed, with a relatively high PS activation efficiency close to 50%. Expectedly, the desired mineralization efficiency of complex actual wastewater was also identified. Eco-friendliness of the application mode was confirmed by the leaching toxicity and acute bio-toxicity tests. Physicochemical properties of the sludge biochar were comprehensively characterized by various techniques. Combined with a series of mechanism analysis, ·OH, SO 4 ·-, ·O 2 -, 1O 2 , free electron all participated in pollutants removal process and the non-radical pathway of electron transfer dominated the reaction. The generated metastable complex [SBC-PS*] confirmed by in situ FT-IR and Raman spectra was the most important active species for electron transfer and PS decomposition. Due to the high efficiency and stability, the sludge biochar adsorbent/PS catalytic system provides a promising way for waste reuse and advanced wastewater treatment. [Display omitted] • The proposed biochar adsorbent with large surface area promotes PS activation. • Desired mineralization efficiency is achieved by the small dosage of PS and biochar. • Toxicity of the biochar/PS catalytic system is relatively low with eco-friendliness. • Most important active species [SBC-PS*] is verified by FT-IR and Raman spectra. • Active sites for PS activation and pollutant degradation are systematically explored. [ABSTRACT FROM AUTHOR]

The unique properties of heterostructure materials make them become a promising candidate for high-performance room-temperature (RT) NO 2 sensing. Herein, a p-n heterojunction consisting of two-dimensional (2D) MoS 2 nanoflakes vertically grown on one-dimensional (1D) SnO 2 nanotubes (NTs) was fabricated via electrospinning and subsequent hydrothermal route. The sulfur edge active sites are fully exposed in the MoS 2 @SnO 2 heterostructure due to the vertically oriented thin-layered morphology features. Moreover, the interface of p-n heterojunction provides an electronic transfer channel from SnO 2 to MoS 2 , which enables MoS 2 act as the generous electron donor involved in NO 2 gas senor detection. As a result, the optimized MoS 2 @SnO 2 -2 heterostructure presents an impressive sensitivity and selectivity for NO 2 gas detection at RT. The response value is 34.67 (R a /R g) to 100 ppm, which is 26.5 times to that of pure SnO 2. It also exhibits a fast response and recovery time (2.2 s, 10.54 s), as well as a low detection limit (10 ppb) and as long as 20 weeks of stability. This simple fabrication of high-performance sensing materials may facilitate the large-scale production of RT NO 2 gas sensors. [Display omitted] • Thin-layers MoS 2 nanoflakes grown vertically on SnO 2 nanotubes were synthesized by a simple strategy. • p-n heterojunctions provide a pathway for electron transfer and target gas diffusion. • Optimized MoS 2 @SnO 2 sensor presents 26.5 times response value to that of pure SnO 2. • Fast response and recovery time (2.2 s, 10.54 s), low detection limit (10 ppb). • The sensor maintains a good stability in the whole 20 weeks. [ABSTRACT FROM AUTHOR]

As an emerging carbonaceous material, carbon aerogels (CAs) display a great potential in environmental cleanup. In this study, a macroscopic three-dimensional monolithic cobalt-doped carbon aerogel was developed by co-condensation of graphene oxide sheets and resorcinol-formaldehyde resin in the presence of cobalt ions, followed by lyophilization, carbonization and thermal treatment in air. Cobalt ions were introduced as a polymerization catalyst to bridge the organogel framework, and finally cobalt species were retained as both metallic cobalt and Co 3 O 4 , wrapped by graphitized carbon layers. The material obtained after a thermal treatment in air (CoCA-A) possesses larger BET specific surface area and pore volume, better hydrophilicity and lower leaching of cobalt ions than that without the post-treatment (CoCA). Despite of a lower loading of cobalt content and a larger mass transfer resistance than traditional powder catalysts, CoCA-A can efficiently eliminate organic contaminants by activation of peroxymonosulfate with a low activation energy. CoCA-A can float beneath the surface of aqueous solution and can be taken out completely without any changes in morphology. The monolith is promising to be developed into an alternative water purification technology due to the easily separable feature. [ABSTRACT FROM AUTHOR]

Highly ordered iron, nitrogen, and fluorine tri-doped TiO 2 (Fe, (N, F)-TiO 2 ) nanotube arrays were successfully synthesized by a facile one-step electrochemical method in an NH 4 F electrolyte containing Fe ions. The morphology, structure, composition, and photoelectrochemical property of the as-prepared nanotube arrays were characterized by various methods. The photoactivities of the samples were evaluated by the degradation of phenol in an aqueous solution under visible light. Tri-doped TiO 2 showed higher photoactivities than undoped TiO 2 under visible light. The optimum Fe 3+ doping amount at 0.005 M exhibited the highest photoactivity and exceeded that of undoped TiO 2 by a factor of 20 times under visible light. The formation of N 2p level near the valence band (VB) contributed to visible light absorption. Doping fluorine and appropriate Fe 3+ ions reduced the photogenerated electrons–holes recombination rate and enhanced visible light photoactivity. The X-ray photoelectron spectroscopy (XPS) and Fourier transform infrared spectroscopy (FTIR) results indicated the presence of synergistic effects in Fe, N, and F tri-doped TiO 2 , which enhanced visible light photoactivity. The Fe, (N, F)-TiO 2 photocatalyst exhibited high stability. [ABSTRACT FROM AUTHOR]

More information is needed to fully comprehend how acid mine drainage (AMD) affects the phototransformation of antibiotic resistant bacteria (ARB) and antibiotic resistance genes (ARGs) in karst water and sewage-irrigated farmland soil with abundant carbonate rocks (CaCO 3) due to increasing pollution of AMD formed from pyrite (FeS 2). The results showed FeS 2 accelerated the inactivation of ARB with an inactivation of 8.7 log. Notably, extracellular and intracellular ARGs and mobile genetic elements (MGEs) also experienced rapid degradation. Additionally, the pH of the solution buffered by CaCO 3 significantly influenced the photo-inactivation of ARB. The Fe2+ in neutral solution was present in Fe(II) coordination with strong reducing potential and played a crucial role in generating •OH (7.0 μM), which caused severe damage to ARB, ARGs, and MGEs. The •OH induced by photo-Fenton of FeS 2 posed pressure to ARB, promoting oxidative stress response and increasing generation of reactive oxygen species (ROS), ultimately damaging cell membranes, proteins and DNA. Moreover, FeS 2 contributed to a decrease in MIC of ARB from 24 mg/L to 4 mg/L. These findings highlight the importance of AMD in influencing karst water and sewage-irrigated farmland soil ecosystems. They are also critical in advancing the utilization of FeS 2 to inactivate pathogenic bacteria. [Display omitted] • Pyrite (FeS 2) accelerated the inactivation of ARB. • ARGs and MGEs underwent fast degradation due to •OH. • The most serious damage of ARB and ARGs were impacted by pH buffered by CaCO 3. • The •OH induced by FeS 2 caused the damage of cell membranes, proteins and DNA. • The resistance of bacteria was inhibited due to destruction of ARB, ARGs and MGEs. [ABSTRACT FROM AUTHOR]

Composite polyurethane (PU) foams were made via the polymerization of toluene diisocyanate (TDI) and polyether polyol with activated carbon fiber, and immobilized microorganisms on polyurethane (IPU) foam were prepared by cultivating the microbe B350 in a mixture of culture medium and PU. We used batch adsorption techniques to study the removal of Cu(II) ions from aqueous solutions via PU and IPU. Moreover, the effects of pH, temperature, carrier amount, and biosorption time on the removal rate of Cu(II), adsorption equilibrium, and adsorption kinetics were investigated in detail. The IPU showed an excellent removal rate for Cu(II). The adsorption kinetics data were in good agreement with the pseudo-second-order rate model, and the adsorption isotherms could be adequately described by the Langmuir equation. For synthetic wastewater containing Cu(II), the removal rates for Cu(II) and COD after 4h treatment were 85% and 80%, respectively. [Copyright &y& Elsevier]

The high-selectivity and high-sensitivity determination of trace concentrations of toxic gases is a major challenge when using semiconductor metal oxide (SMO) gas sensors in complicated real-world environments. In this study, by strategically combining a three-dimensional inverse opal (3DIO) macroporous ZnO substrate and a ZIF-8 outer filter membrane, two series of sensors with Pt NPs loaded at different locations are developed. In the optimal 3DIO ZnO@ZIF-8/Pt sensor, the existence of small Pt NPs in ZIF-8 cavities can effectively accelerate the absorption of H 2 S, capture electrons from the N site of ZIF-8, and donate the electron to the S site of H 2 S, as indicated by density functional theory simulations, leading to a significantly increased response to H 2 S. Together with the molecular-sieving effect that ZIF-8 exerts on gas molecules with larger kinetic diameters, the 3DIO ZnO@ZIF-8/Pt sensor exhibits a high response to H 2 S (118–5.5 ppm), a detection limit of 40 ppb, and importantly, a 59-fold higher selectivity to H 2 S against typical interference gases. In addition, the 3DIO ZnO@ZIF-8/Pt sensor is developed as a multi-platform sensor to evaluate trace concentrations of H 2 S in meat quality assessment, halitosis diagnosis, and automobile exhaust assessment. [Display omitted] • The 3DIO ZnO@ZIF-8/Pt sensor is designed as a multi-platform for H 2 S detection. • Small Pt NPs in outer ZIF-8 cavities effectively activate the H 2 S sensing. • The molecular-sieving effect of ZIF-8 also contributes to the high selectivity. • The sensor exhibits high response of 118–5.5 ppm H 2 S. • The sensor used in H 2 S assessment of meat quality, halitosis and vehicle exhaust. [ABSTRACT FROM AUTHOR]

Microplastic (MP) release from household plastic products has become a global concern due to the high recorded levels of microplastic and the direct risk of human exposure. However, the most widely used MP measurement protocol, which involves the use of deionized (DI) water, fails to account for the ions and particles present in real drinking water. In this paper, the influence of typical ions (Ca2+/HCO 3 -, Fe3+, Cu2+) and particles (Fe 2 O 3 particles) on MP release was systematically investigated by conducting a 100-day study using plastic kettles. Surprisingly, after 40 days, all ions resulted in a greater than 89.0% reduction in MP release while Fe 2 O 3 particles showed no significant effect compared to the DI water control. The MP reduction efficiency ranking is Fe3+ ≈ Cu2+ > Ca2+/HCO 3 - > > Fe 2 O 3 particles ≈ DI water. Physical and chemical characterization using SEM-EDX, AFM, XPS and Raman spectroscopy confirmed Ca2+/HCO 3 -, Cu2+ and Fe3+ ions are transformed into passivating films of CaCO 3 , CuO, and Fe 2 O 3 , respectively, which are barriers to MP release. In contrast, there was no film formed when the plastic was exposed to Fe 2 O 3 particles. Studies also confirmed that films with different chemical compositions form naturally in kettles during real life due to the different ions present in local regional water supplies. All films identified in this study can substantially reduce the levels of MP release while withstanding the repeated adverse conditions associated with daily use. This study underscores the potential for regional variations in human MP exposure due to the substantial impact water constituents have on the formation of passivating film formation and the subsequent release of MPs. [Display omitted] • Ions present in water can lead to film formation that suppresses microplastic release by 97%. • Fe 2 O 3 particles in water does not lead to film formation and has minimal effect on microplastic release. • The suppression ranking of constituents: Fe3 + ≈ Cu2+ > Ca2+/HCO 3 - > > Fe 2 O 3. • Human exposure to microplastics should vary regionally depending on local water constituents. [ABSTRACT FROM AUTHOR]

In this study, a novel iron and nitrogen co-doped biochar (Fe/N-biochar) was successfully prepared and employed as an efficient adsorbent for micropollutants. The maximum adsorption capacity of Fe/N-biochar for bisphenol A (BPA) was 54 mg/g, which is significantly better than that of commercial graphene (19 mg/g) and activated carbon (6 mg/g). Additionally, for eight other common micropollutants (e.g., phenol, acetaminophen, and sulfamethoxazole), Fe/N-biochar also exhibited highly enhanced adsorption performance. The results of adsorption kinetics and isotherms studies showed that the adsorption of micropollutants onto Fe/N-biochar is by monolayer coverage. Thermodynamic studies further suggested that the adsorption process is feasible, spontaneous, and chemical in nature. The adsorption mechanism was investigated by correlation analysis between the adsorption capacity and the physiochemical properties of Fe/N-biochar. The results demonstrated that the strengthening of π–π electron donor-acceptor interactions between the organics and the adsorbent caused by the co-doping of iron and nitrogen was the dominant driving force behind the efficient adsorption of micropollutants. Furthermore, graphitic N and Fe−N x were identified as the major adsorption sites. Simple heat treatment could effectively restore the adsorption capacity of Fe/N-biochar that had reached adsorption equilibrium. In view of its simple preparation method, highly enhanced adsorption capacity, and excellent recyclability, the prepared Fe/N-biochar can be regarded as a promising candidate for wastewater treatment. [Display omitted] • Fe/N-biochar exhibits enhanced adsorptive removal of micropollutants. • Fe/N-biochar has 10.8 times higher adsorption capacity than pristine biochar. • Strong π−π interactions are the main driving force for adsorption of organics. • Graphitic N and Fe−N x are identified to be the primary adsorption sites. • Heat treatment can effectively restore the adsorption ability of used adsorbent. [ABSTRACT FROM AUTHOR]

With the increasing application of nanomaterials, evaluation of the phytotoxicity of nanoparticles has attracted considerable interest. Buckwheat is an economically pseudocereal crop, which is a potential model for investigating the response of plants to hazardous materials. In this study, the response of buckwheat to graphene oxide (GO) was investigated by integrating physiological and transcriptome analysis. GO can penetrate into buckwheat root and stem, and high concentrations of GO inhibited seedlings growth. High concentration of GO improved ROS production and regulated the activities and gene expression of oxidative enzymes, which implying GO may affect plant growth via regulating ROS detoxification. Root and stem exhibit distinct transcriptomic responses to GO, and the GO-responsive genes in stem are more enriched in cell cycle and epigenetic regulation. GO inhibited plant hormone biosynthesis and signaling by analyzing the expression data. Additionally, 97 small secreted peptides (SSPs) encoding genes were found to be involved in GO response. The gene expression of 111 transcription factor (TFs) and 43 receptor-like protein kinases (RLKs) were regulated by GO, and their expression showed high correlation with SSPs. Finally, the TFs-SSPs-RLKs signaling networks in regulating GO response were proposed. This study provides insights into the molecular responses of plants to GO. [Display omitted] • Graphene oxide (GO) can penetrate into root and stem, and GO significantly inhibited the growth of buckwheat seedlings. • GO may affect buckwheat growth via regulating ROS detoxification. • Root and stem of buckwheat exhibit distinct transcriptomic responses to GO. • The genes involved in cell cycle, epigenetic regulation, and plant hormones showed response to GO. • The networks mediated by TFs-SSPs-RLKs signaling modules in regulating GO response were proposed. [ABSTRACT FROM AUTHOR]

The abuse of antibiotics has triggered the rise of drug-resistance bacteria, which has seriously threatened public health globally. As a result, carrying out efficient and accurate antibiotic and bacteria identification are quite significant but challenge. Herein, an unprecedented Cd-MOF-based sensor, [CdL] n [ 1 , H 2 L = 4-(2-methyl-1H-benzo[ d ]imidazol-1-yl) isophthalic acid] with multiple fluorescence response behaviours towards antibiotics and bacteria was developed. Single-crystal X-ray diffraction revealed that 1 is a mesomeric 2D bilayer, which is comprised of two opposite chiral mono-layers, each assembled by left-handed or right-handed helixes. More interestingly, 1 represented multiplex detection capability towards antibiotics and bacteria through two detection behaviors: toward nitro-antibiotics and chlortetracycline (CTC) via fluorescent quenching, while toward Staphylococcus albus (S. albus) via fluorescent enhancement. Remarkably, 1 showed a low limit of detection (LOD, 47 CFU/mL) accompanied with specificity in the detection of S. albus compared to other bacteria, such as Staphylococcus aureus , Acinetobacter baumannii , Klebsiella pneumonia , Pseudomonas aeruginosa and Escherichia coli. In addition, the LOD could reach to ppm level for nitro-antibiotics and CTC. Moreover, the practical application of 1 was further reinforced through the detection of nitro-antibiotics and CTC, as well as S. albus in fetal calf serum and river water. [Display omitted] • An unprecedented highly stable Cd-MOF multiple fluorescence sensor was reported. • This sensor can rapidly and efficiently identify antibiotics or bacteria. • It can be as "turn-off" sensor towards nitro antibiotics and chlortetracycline. • It can be as "emission enhancement" sensor towards Staphylococcus albus. [ABSTRACT FROM AUTHOR]

Abstract: Batch sorption experiments were conducted using macroreticular poly(vinyl alcohol) (MR-PVA) beads as a adsorbent to adsorb Pb(II) from both single component system and multi-metal solution in which experimental parameters were studied including solution pH, contact time, adsorbent dose, initial concentration of metal ions and ionic strength. The equilibrium isotherms were determined at pH 6 under constant ionic strength and at different temperatures. The results showed that the maximum adsorption capacity of Pb(II) (213.98mgg−1) with 1gL−1 of adsorbent was observed at 300mgL−1 at an initial pH value of 6.0 under temperature of 288K. Removals of about 60% occurred in 30min, and equilibrium was attained at around 150min. The equilibrium data for the adsorption of Pb(II) on MR-PVA beads was tested with various adsorption isotherm models among which three models were found to be suitable for the Pb(II) adsorption. In addition, the kinetic adsorption fitted well to the pseudo-second-order model and the corresponding rate constants were obtained. Thermodynamic aspects of the adsorption process were also investigated. [Copyright &y& Elsevier]

This work illustrates a simple polymer thermal treatment strategy to develop high-dispersed Fe 2 O 3 /Fe nanoparticles residing in honeycomb-like N-doped graphitic carbon (Fe 2 O 3 /Fe@N-GC). The as-prepared Fe 2 O 3 /Fe@N-GC composites consist of three-dimensional (3D) strutted interconnective graphitic carbon frame, which would not only refrain from restacking and facilitate the charge transfer, but also provide more reaction interface between gas molecules and materials. Benefiting from the synergistic merits of Fe 2 O 3 /Fe, N-doping graphitic carbon, high surface area and unique 3D architectures, the optimal Fe 2 O 3 /Fe@N-GC presents impressive sensitivity and selectivity for NO 2 gas detection at room temperature with the response of 25.48–100 ppm, response time of 2.13 s, recovery time of 11.73 s, detection limit of 10 ppb and as long as 60 days of stability. As a result, the present Fe 2 O 3 /Fe@N-GC composite with an easy fabrication method and high sensitivity, selectivity, stabitliy towards NO 2 at RT would inspire various designs based on the 3D honeycomb structure for more real applications in gas sensors. ga1 • Honeycomb embedded with Fe 2 O 3 /Fe nanoparticles was synthesized by a simple strategy. • Honeycomb provides the pathway for fast electron and target gas diffusion. • The response of optimized Fe 2 O 3 /Fe@N-GC sensor to 100 ppm NO 2 at RT is 25.48. • The sensor maintains a good stability in the whole 60 days. [ABSTRACT FROM AUTHOR]