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A novel thiol-functionalized graphene oxide/Fe-Mn composite (SGO/Fe-Mn) was synthesized via three different methods, i.e., acetic acid method (SGO/Fe-Mn-ac), neutral method (SGO/Fe-Mn-ne), and ammonium hydroxide method (SGO/Fe-Mn-am). The composites were characterized and tested for aqueous methylmercury removal. SGO/Fe-Mn was prepared using 3-mercaptopropyltrimethoxysilane (3-MPTS) as a silanizing reagent, and hydrolyzed 3-MPTS mainly interacted with GO/Fe-Mn through surface oxygen-containing groups (i.e., OH, C O, epoxy C O C, carboxyl O C O, and C O) and π-π interactions, partially through self-polymerization. SGO/Fe-Mn-am showed the largest hydrodynamic diameter, strongest π-π bond, fewest S oxidation products, most thiol groups, negative charge, sp 3 defects, and FeOOH. Pseudo-second-order kinetic model and Langmuir and Freundlich isotherm models fitted well with methylmercury sorption kinetic and isotherm data, respectively, resulting in a CH 3 Hg + maximum sorption capacity of 43.88 mg/g for SGO/Fe-Mn-am, 36.33 mg/g for SGO/Fe-Mn-ac, and 28.00 mg/g for SGO/Fe-Mn-ne. The removal mechanism was described by electrostatic attraction, ligand exchange, and surface complexation. This study demonstrates potential and viability of SGO/Fe-Mn for enhanced immobilization of CH 3 Hg + in surface water, groundwater, and soil/sediments.

The current study investigated the role of the automatization of stimulus and response (S-R) associations and response readiness in triggering the motor activation for masked primes in two experiments. The automatization of associations was manipulated by employing different types of stimuli, and response readiness was manipulated by varying the relative frequency of Go trials in a modified Go/No-Go task. Compatibility (compatible and incompatible), stimulus type (arrows and parallel lines), and test session (Sessions 1, 2, and 3) were manipulated in a high response-readiness condition (Experiment 1) and in a low response-readiness condition (Experiment 2). Negative compatibility effects (NCEs) occurred regardless of session and experiment in the arrow stimuli condition. However, in the parallel-line stimuli condition, no significant compatibility effect (CE) appeared regardless of the experiment in Sessions 1 and 2, whereas a significant NCE appeared in Experiment 1 but not in Experiment 2 in Session 3. These results are consistent with the claim that motor activation can only occur if the association between specific stimuli and specific responses has been automatized by previous practice, and response readiness can modulate the development of automaticity, but this modulation will have a minimal effect once the association is automatized. The findings also provide experimental evidence for the assumption that the formation of association-based automaticity could be modulated by top-down control (e.g., response readiness).

This study investigated the effects of 3 model oil dispersants (Corexit EC9500A, Corexit EC9527A and SPC 1000) on photodegradation of pyrene under simulated sunlight. Both Corexit dispersants enhanced photodegradation of pyrene, while SPC1000 slightly inhibited the reaction. Span 80 and Tween 85 were the key ingredients causing the effects, though the underlying mechanisms differed. Span 80 enriches pyrene in the upper layer of water column, whereas Tween 85 induces a photosensitization process. Two reactive oxygen species, 1O2 and O2-, were found responsible for pyrene photodegradation, though the presence of EC9500A suppressed the 1O2 pathway. In terms of photodegradation products, EC9500A enhanced generation of polyaromatic intermediates, i.e., phenaleno[1,9-cd][1,2]dioxine, 1-hydroxypyrene, and 1,8-pyrenequinone, but did not alter the classical photodegradation pathway. The Corexit dispersants were more prone to photochemical decomposition, with multiple by-products detected. The information aids in our understanding of the effects of dispersants on photochemical weathering of oil compositions.

Excess natural organic matter (NOM) in water not only lead to unpleasant black color and dissolved oxygen depletion in wastewater and natural water body but also causes carcinogenic chlorinated organic byproduct during drinking water chlorine disinfection. We try to develop a novel cost-effective and green technology for water NOM removal. In our simulated NOM removal process using humic acid (HA) as typical organic matter, we find that mesoporous nano-MgO performs an abnormally high NOM removal capacity (1260 mg-HA/g-MgO, or 446 mgC/g-MgO) when coupled with microfiltration membrane separation, which can’t be illustrated by traditional adsorption mechanism. Actually, Mg2+ from dissolved Mg(OH)2 contributes ∼ 92% NOM removal via coagulation while Mg(OH)2 is responsible for the residue ∼ 8% via adsorption. MgO serves as a two-in-one coagulant and adsorbent. The MgO treatment process is highly pH sensitive and weak acidic condition is favored for high NOM removal efficiency. MgO can be regenerated for more than 10 circulations by annealing Mg(OH)2/Mg-NOM composite at 500 °C, so that our MgO recycling process will be sustainable without the need of continuous chemical purchase. More importantly, no solid waste is generated in this novel process. This MgO-recycling NOM-removal process is simple, efficient, and sustainable for water NOM removal and will be significant in promoting novel sustainable technologies for NOM- or HA-related water remediation and treatment while minimizing the generation of solid waste.

Fully stabilized FeS nanoparticles were prepared with water-soluble carboxymethyl cellulose (CMC) as a stabilizer, and investigated for adsorption of lead (Pb2+) ions from simulated drinking water. The optimum particle stabilization was achieved using 0.0025 wt.% of CMC for 50 mg/L FeS (i.e., CMC-to-FeS molar ratio of 0.0005). The particle stabilization technique increased lead removal from 78.1% to 90.3%. However, further increasing the CMC-to-FeS molar ratio to 0.0025 diminished the removal. Rapid adsorption kinetics of Pb by CMC-FeS was observed with an equilibrium time of 240 min. The kinetic data was adequately fitted by a pseudo-second-order kinetic model. The adsorption isotherm showed a sigmoidal S-shape due to complexation of Pb with soluble CMC molecules, and the Sigmoidal isotherm model well fitted the adsorption isotherm data with a maximum monolayer adsorption capacity of 77.0 mg/g. FTIR and XRD analyses indicated that both surface complexation and chemical precipitation (in the form of PbS) were the dominant adsorption mechanisms. Pb uptake was enhanced with increasing CMC-FeS dosage from 10 to 125 mg/L and increasing pH from 4.5 to 8.5. The material can perform well under typical concentrations of a model humic acid (HA) and salts. Yet, unusually high concentrations of HA or hardness ions may exerted elevated inhibitive effect. The findings indicated that CMC-stabilized FeS nanoparticles are promising for effective immobilization of lead in contaminated water and soil.

Hydrous zirconium oxide (HZO) encapsulated alginate gel beads were synthesized for phosphate recovery from water. Importantly, we find that HZO/alginate gel beads (ZrA) crosslinked with Ca2+, Mg2+, Fe3+, Al3+, and Zr4+ are unstable under an intense alkali regeneration condition. Only Sr2+-crosslinked ZrA can endure a high alkali solution. ZrA possesses a high specific surface area (80.84 m2·g−1) and a mesoporous structure (15.3 nm and 0.196 cm3·g−1), which endow them with a high Langmuir adsorption capacity of 52.5 mg-P/g. ZrA can be easily recycled, and the mass loss of HZO is prevented. Furthermore, the strontium alginate gel framework protects the encapsulated HZO nanoparticles from adverse humic acid contamination. ZrA can be regenerated for at least 5 adsorption/desorption cycles. Cost analysis indicates the potential scale application feasibility for ZrA. This study provides a novel, simple, and environmentally benign solution to immobilize HZO for efficient phosphate recovery.

Mercury (Hg) contamination in soil is a paramount concern to the environment and public health. Yet, effective in situ remediation technologies have been lacking. In this study, a novel thiol-functionalized graphene oxide/Fe-Mn (SGO/Fe-Mn) composite was prepared and investigated for in situ immobilization of Hg in contaminated soil. Batch tests showed that application of SGO/Fe-Mn at doses of 0.4% and 0.8% effectively reduced H2O, H2SO4 and HNO3, CH3COOH, and CaCl2-extractable Hg by 90.3-98.9% and 96.5-98.9%, respectively, upon equilibrium after 72 d. An increasing of soil moisture content from 0 to 12.5% significantly enhanced the immobilization efficiency from 75.0% to 97.6%. XRD, FTIR, and XPS analyses suggested that the composite mainly immobilized Hg through surface complexation and chemical precipitation. Sequential extraction procedure demonstrated that the composite promoted the conversion of more accessible Hg (exchangeable and carbonate fractions) into the less accessible forms, i.e., oxides, organic matter, and residual fractions, resulting in substantially reduced environmental risk of Hg. The application of SGO/Fe-Mn enhanced soil cation exchange capacity, available N and K, and total organic carbon, and can be used to effectively improve soil properties. Moreover, immobilized Hg in soil by this composite remained stable over one year. The present study demonstrates the potential and viability of SGO/Fe-Mn for enhanced immobilization of Hg in soil and sediment.

In this investigation, we propose a strip segmentation phase (SSP) method for a spatial light modulator (SLM) to generate independent multifocal spots when the beam passes through a high numerical aperture (NA) lens. With the SSP method, multifocal spots can be generated with each spot independently, flexibly and uniformly distributed. The performance of the SSP method is first validated with numerical simulation. Then, by applying the modulation method with SLM and importing the beams into an inverted fluorescence microscopy system with a high-NA lens, the spot distribution and their shapes can be observed by fluorescent image. The fluorescent image exhibits high uniformity and high consistency with the aforementioned numerical simulations. Finally, we dynamically load a series of phase maps on SLM to realize continuous and independent spot movement in a multifocal array. By laser direct writing on photoresist, a complex NWU-shape structure can be realized flexibly with multi-task fabrication capability. The SSP method can significantly improve the efficiency and flexibility of laser direct writing. It is also compatible with most recent techniques, e.g., multiphoton absorption, stimulated emission depletion and photo-induced depolymerization etc., to realize parallel super-resolution imaging and fabrications.

As the traditional anode material of lithium-ion batteries, tin dioxide (SnO2) has the characteristics of a high theoretical capacity and stable crystal structure. However, the alloying/de-alloying reaction between tin and lithium ions causes volume expansion and continuously generates an SEI film, which causes the electrode to fall off the current collector and the capacity fade rapidly. Generally, a composite of carbon materials and SnO2 can alleviate the expansion and pulverization phenomena. However, the microstructure of carbon materials is complex and changeable, which makes it difficult to definitively state the influence mechanism of the microstructure on the lithium storage performance of composite materials. Here, three kinds of lignin-based porous carbons (LPCs) with different microstructural characteristics, along with a high graphitization, high specific surface area and hierarchical porosity, are obtained by regulating the process of gas exfoliation and in situ activation. Furthermore, a series of LPC/SnO2 composites are obtained by an ultrasonic dispersion and ball milling method. Electrochemical property results show that the hierarchical porous LPCs are more conducive to the dispersion/coating of SnO2 nanoparticles and that the reversible specific capacity of the electrode material increases from 64 to 620 mA h g−1, effectively mitigating the expansion and pulverization of SnO2 during the lithium storage process.

Rapid industrialization, urbanization, and population growth have led to the common occurrence of black-stinking urban rivers. Assessing regional anthropogenic influences is beneficial to develop effective remediation strategies. This study comprehensively investigated the occurrence and fate of linear alkylbenzenes (LABs) as molecular markers of anthropogenic influences in three media (filtered water, suspended particulate matter (SPM), and sediment) in a highly urbanized river (Baihaimian River) in Guangzhou, South China. The concentrations of LABs ranged from 41 to 215 ng/L in the dissolved phase, from 7122 to 46,640 ng/g dry weight in the SPM phase, and from 73 to 3650 ng/g dry weight in surface sediments (0–10 cm depth). The spatial distribution of LABs was probably affected by the surrounding environment, river flux, and sediment properties. No biotransformation of LABs in water samples and a slight biotransformation in sediments were observed. Significant correlations were found between total nitrogen, ammonia nitrogen, and LABs in river water, indicating the same domestic wastewater sources. The positive correlation between total organic carbon (TOC) and LABs in sediments suggested that TOC worked as the controlling factor for the redistribution of LABs and that local sewage discharge was the dominant TOC input. The total mass inventory of LABs in sediment in Baihaimian River was 21 kg. The total mass of LABs released into Baihaimian River was 183 kg per year, among them, 63% was discharged into the adjacent Liuxi River.

Zinc (Zn2+) and cadmium (Cd2+) in water pose serious threats to human health and the environment. In search for a more effective treatment technology, we prepared a type of carboxymethyl cellulose (CMC) bridged chlorapatite (CMC-CAP) nanoparticles and tested the material for removal of Zn2+ and Cd2+ from water. CMC macromolecules were attached to CAP by bidentate bridging and hydrogen bonding, preserving the high adsorption capacity of CAP nanoparticles while allowing for easy gravity-separation of the nanoparticles. CMC-CAP showed rapid adsorption kinetics and 22.8% and 11.2% higher equilibrium uptake for Zn2+ and Cd2+, respectively, than pristine CAP. An extended dual-mode isotherm model, which takes into account both sorption and chemical precipitation, provided the best fits to the sorption isotherms, giving a maximum Langmuir sorption capacity of 141.1 mg g−1 for Zn2+ and 150.2 mg g−1 for Cd2+ by CMC-CAP. Na+ at up to 5 mM showed modest effects on the uptake of the heavy metals, while 2–5 mM of Ca2+ exerted notable inhibitive effects. Dissolved organic matter (up to 5 mg L−1 as TOC) inhibited the Zn2+ uptake by 16.5% but enhanced the Cd2+ removal by 8.6%. Material characterizations and surface binding analyses revealed that ion exchange, surface precipitation, and surface complexation were the removal mechanisms for the heavy metals. This study demonstrates stabilizer bridging may serve as a convenient strategy to facilitate water treatment uses of nanoparticles.

This work developed a new method to determine concentration of Corexit EC9500A, and likely other oil dispersants, in seawater. Based on the principle that oil dispersants decrease surface tension, a linear correlation was established between the dispersant concentration and surface tension. Thus, the dispersant concentration can be determined by measuring surface tension. The method can accurately analyze Corexit EC9500A in the concentration range of 0.5-23.5mg/L. Minor changes in solution salinity (

Electroplating sludge (ES) containing large quantities of heavy metals is regarded as a hazardous waste in China. This paper introduced a simple method of treating ES using environmentally friendly fixatives biochar (BC) and iron sulfide (FeS), respectively. After 3 days of treatment with FeS at a FeS-to-ES mass ratio of 1:5, the toxicity characteristic leaching procedure (TCLP)-based leachability of total Cr (TCr), Cu(II), Ni(II), Pb(II), and Zn(II) was decreased by 59.6, 100, 63.8, 73.5, and 90.5 %, respectively. After 5 days of treatment with BC at a BC-to-ES mass ratio of 1:2, the TCLP-based leachability was declined by 35.1, 30.6, 22.3, 23.1, and 22.4 %, respectively. Pseudo first-order kinetic model adequately simulated the sorption kinetic data. Structure and morphology analysis showed that adsorption, electrostatic attraction, surface complexation, and chemical precipitation were dominant mechanisms for heavy metals immobilization by BC, and that chemical precipitation (formation of metal sulfide and hydroxide precipitates), iron exchange (formation of CuFeS2), and surface complexation were mainly responsible for heavy metals removal by FeS. Economic costs of BC and FeS were 500 and 768 CNY/t, lower than that of Na2S (940 CNY/t). The results suggest that BC and FeS are effective, economic, and environmentally friendly fixatives for immobilization of heavy metals in ES before landfill disposal.

Rapid industrialization and urbanization have resulted in elevated concentrations of hazardous inorganic and organic contaminants in groundwater and soil, which has become a paramount concern to the environment and the public health. In recent years, iron sulfide (FeS), a major constituent of acid-volatile sulfides, has elicited extensive interests in environmental remediation due to its ubiquitous presence and high treatment efficiency in anoxic environment. This paper provides a comprehensive review on recent advances in: (1) synthesis of FeS particles (including nanoscale FeS); and (2) reactivity of FeS towards a variety of common environmental contaminants in groundwater and soil over extended periods of time, namely, heavy metals (Hg(II), Cu(II), Pb(II), and Cr(VI)), oxyanions (arsenite, arsenate, selenite, and selenate), radionuclides (e.g., uranium (U) and neptunium (Np)), chlorinated organic compounds (e.g., trichloroethane, trichloroethylene, and p-chloroaniline), nitroaromatic compounds, and polychlorinated biphenyls. Different physiochemical and biological methods for preparing FeS with desired particle size, structure, and surface properties are discussed. Reaction principles and removal effectiveness/constraints are discussed in details. Special attention is placed to the application of nanoscale FeS particles because of their unique properties, such as small particle size, large specific surface area, high surface reactivity, and soil deliverability in the subsurface. Moreover, current knowledge gaps and further research needs are identified.

Microplastics (MPs) have aroused rising social concerns. Although amounts of surfactants exist in wastewater and are expected to alter the surface properties of MPs significantly as they are designed to be adsorbed by hydrophobic particles. However, rare works have been done on the influence of surfactants on the coagulation removal process of MPs which was thought to be an effective way to remove MPs together with other natural particles, such as clay. We used 3-D fluorescence imaging to track the coagulation removal process of polystyrene MPs. Our results indicate that nonionic surfactant, tween 20 in ppm scale, could inhibit the coagulation removal of polystyrene MPs significantly. Residue MPs in the effluent is proportional with the surfactant concentration and increases up to tens of times, which will lead to a dramatic increase in their potential environmental risks. Apparent size effect exists in the coagulation in which smaller MPs can escape from the coagulation removal more easily. Mechanism study suggests that the steric resistance of the hydrophilic flexible polyethylene glycol (PEG) layer formed by tween 20 adsorbed on MP surface inhibits clay deposition and thus hinders subsequent agglomeration and precipitation. A surfactant stealth effect, which is used in the design of nanomedicine to avoid the human immune recognition and clearance of nano-drugs from blood circulation, also exists in the coagulation removal process of MPs. Our finding not only proves the strong influence of surfactants on MPs but also will stimulate related studies on other latent surfactant effects of MPs.

Mercury contamination poses a serious threat to the ecological system and human health. Yet, removal of mercury at parts per billion (ppb) level in surface water is difficult to achieve. This study developed a Mg2Al layered double hydroxide supported iron sulfide composite (FeS@Mg2Al-LDH) and investigated its removal effectiveness and mechanisms of mercury from surface water. FeS was successfully soldered onto Mg2Al-LDH via surface complexation and surface adsorption. The composite (FeS:Mg2Al-LDH mass ratio of 1:1) at 20 mg/L effectively removal 89.4% of 110 µg/L mercury at pH 7.0 within 72 h. A pseudo-second-order kinetic model well simulated the sorption kinetic data and a Sigmoidal Langmuir isotherm model perfectly fitted the sorption isotherm data with a maximum monolayer sorption capacity of 116.96 mg/g. X-ray powder diffraction (XRD), Fourier transform infrared (FTIR), and X-ray photoelectron spectroscopy (XPS) analyses suggested that mercury was removed via chemical precipitation, ion exchange, and surface complexation. The supporting material Mg2Al-LDH greatly enhanced the antioxygenic and pH-resistant properties of FeS, and the composite offered high selectivity for mercury. FeS@Mg2Al-LDH and immobilized mercury remained stable over 6 months. This study demonstrated the potential and viability of FeS@Mg2Al-LDH for efficient removal of aqueous mercury.

Mercury contamination in groundwater has been considered as an environmental and public health issue all over the world. Yet, effective in situ remediation techniques have been lacking. A thiol-modified graphene oxide/Fe–Mn composite (SGO/Fe–Mn) was employed as a reactive sorbent of permeable reactive barrier (PRB) for in situ remediation of mercury contaminated groundwater using fixed-bed columns. Mercury existed as HgCl2, Hg(OH)2, and HgClOH, and was mainly removed through surface complexation. The Brunauer-Emmett-Teller sorption isotherm model provided adequate fitting of the sorption isotherm data with a maximum monolayer sorption capacity of 112.03 ± 16.59 mg g−1. Breakthrough time, the time when 5% of initial Hg concentration is measured in the effluent, increased with the decrease of influent mercury concentration, pore velocity, dissolved oxygen (DO), and dissolved organic matter (DOM). The resultant column sorption capacity was enhanced at higher influent mercury concentration, lower groundwater pore velocity, lower DOM and DO. Moreover, when the SGO/Fe–Mn was thoroughly mixed with quartz sand in the column, the breakthrough time was increased and the resultant sorption capacity was improved compared to the case that SGO/Fe–Mn was packed between two layers of quartz sand. Mathematically, the Adams-Bohart model satisfactorily reproduced the initial behavior of mercury breakthrough curves (

Mercury (Hg) is one of the most toxic heavy metals in soil and groundwater, and mercury methylation is the key step for invasion of Hg into the food chain. Iron sulfide nanoparticles stabilized by carboxymethyl cellulose (CMC-FeS) have demonstrated excellent sorption/immobilization for mercury in water and soil. However, information has been lacking pertaining to the effects of CMC-FeS on speciation and microbial methylation of Hg at part per billion (ppb) level in groundwater. This work studied Hg speciation in the presence of CMC-FeS and the inhibitive effect of CMC-FeS on the microbial methylation of Hg in groundwater. CMC-FeS (CMC-to-FeS molar ratio of 0.0004) offered unusually high Hg sorption capacity, fast sorption rate, and good selectivity for mercury. The maximum Langmuir sorption capacity of CMC-FeS reached 3358.28 mg/g, which was enhanced by 8.81% compared to non-stabilized FeS. X-ray powder diffraction (XRD), Fourier transform infrared (FTIR), and X-ray photoelectron spectroscopy (XPS) analyses suggested that mercury removal was attributed to surface complexation, ion exchange, and chemical precipitation, resulting in the formation of FeS-Hg complexes and mercury sulfide (HgS). Dissolved oxygen had negligible effect on mercury uptake. The simple nanoparticle treatment inhibited mercury methylation by up to 60.8% when tested with a model metal-reducing bacterium Geobacter sulfurreducens PCA. When aged for 6 months, the nanoparticles exhibited excellent physical stability and high mercury capacity, and the immobilized mercury did not show any leaching. The present study provides direct evidence that immobilization of Hg by CMC-FeS remarkably inhibits microbial methylation of Hg, and thus mitigates toxic effects of mercury in water on human and the environmental health.

Cadmium (Cd) is one of the most commonly detected toxic heavy metals in the environment. Ferrous sulfide (FeS) nanoparticles were prepared using sodium carboxymethyl cellulose (CMC) as a stabilizer and tested for removal of Cd from aqueous solutions. Effects of CMC concentration, initial Cd concentration, pH, humic acid (HA) and dissolved oxygen were examined. Fully stabilized FeS (100 mg/L) nanoparticles were obtained using 0.01 wt% CMC. Batch kinetic tests showed that the nanoparticles at 100 mg/L as FeS rapidly removed 93% of 1 mg/L Cd within 4 h at pH 7.0, and the kinetic data were well interpreted by a pseudo-second-order rate model with a rate constant of 6.68 g·mg−1·hr−1. Sorption isotherm was well simulated by a dual-mode isotherm model with a maximum Langmuir sorption capacity of 497.5 mg/L at pH 7.0. Fourier transform infrared (FTIR) spectroscopy and X-ray powder diffraction (XRD) analyses suggested that chemical precipitation and surface complexation between Cd and FeS were dominant immobilization mechanisms. Increasing pH from 4.0 to 8.0 enhanced Cd removal rate from 73.0% to 98.8%, whereas addition of 3 mg/L HA (as total organic matter) inhibited the removal rate by 2.7% and the presence of molecular oxygen had negligible effect. Increasing NaCl or CaCl2 from 0 to 10 mM suppressed Cd removal by 10.1% and 27.7%, respectively. The immobilized Cd remained insoluble when aged for 717 days under anoxic or oxic conditions. This study demonstrated that CMC-stabilized FeS nanoparticles can facilitate long-term immobilization of cadmium in contaminated water.

A novel thiol-functionalized graphene oxide/Fe-Mn (SGO/Fe-Mn) was investigated for aqueous Hg2+ and CH3Hg+ removal. Mercury were removed mainly through ligand exchange and surface complexation with surface active sites (i.e., −SH, OH, O C O, C C, Si O, and π π bond). SH had the strongest binding ability with mercury, forming sulfur-containing organic matter or polymers with Hg2+, and sulfur-containing organometallic compounds or thiolate-like species with CH3Hg+. The BET sorption isotherm model well simulated the sorption isotherm data of Hg2+ (R2=0.995, qm=233.17 mg/g) and CH3Hg+ (R2=0.997, qm=36.69 mg/g), indicating a multilayer adsorption process. The mercury uptake was promoted with the increase of 3-MPTS content, adsorbent dosage, and pH ( 5.5) and high concentrations of humic acid and electrolytes. SGO/Fe-Mn demonstrated high mercury uptake in simulated surface water/groundwater and in the presence of Pb, Cu, Ni, Sb, Cd and Zn. The mercury-laden SGO/Fe-Mn can be successfully regenerated and reused for three times with 98.1% and 67.0% of original Hg2+ and CH3Hg+ sorption capacity when 5% thiourea + 2 M KI was used as the desorbing agent. This study demonstrates potential and viability of SGO/Fe-Mn for mercury remediation.

Oil degradation by surface-level atmospheric ozone has been largely ignored in the field. To address this knowledge gap, this study investigated the ozonation rate and extent of typical petroleum compounds by simulated surface-level ozone, including total petroleum hydrocarbons (TPHs), n-alkanes, and polycyclic aromatic hydrocarbons (PAHs). Moreover, the work explored the effect of a prototype oil dispersant, Corexit EC9500A, on the ozonation rate. Rapid oxidation of TPHs, n-alkanes and PAHs was observed at various gaseous ozone concentrations (i.e. 86, 200 and 300 ppbv). Generally, the presence of the oil dispersant enhanced ozonation of the oil compounds. The addition of humic acid inhibited the reaction, while increasing salinity accelerated the degradation. Both direct ozonation by molecular ozone and indirect oxidation by ozone-induced radicals play important roles in the degradation process. The findings indicate that ozonation should be taken into account in assessing environmental fate and weathering of spilled oil.

Ni/Fe bimetallic nanoparticles have been widely used as strong reductants to degrade organic pollutants. Synthesis parameters of Ni/Fe nanoparticles can directly affect their characteristics and reactivity. In this study, Ni/Fe nanoparticles were prepared at different synthesis conditions, namely, synthesizing temperature, stirring rate, washing solutions, and preparation methods (post-coated and co-reducted Ni/Fe nanoparticles), and investigated their effectiveness of decabrominated diphenyl ether (BDE209) degradation. The results showed that the successive order of factors affecting the kinetics constant of Ni/Fe nanoparticles for the removal of decabrominated diphenyl ether (BDE209) were preparation methods, washing solutions, stirring rate, and synthesis temperature. It should be noted that the kinetics constants of post-coated Ni/Fe nanoparticles for removal of BDE209 was 0.049 min−1, which was 14 times higher than that of co-reducted Ni/Fe nanoparticles. Moreover, the most remarkable influence on the particle size of Ni/Fe nanoparticles was the stirring rate, others synthesis conditions are mentioned in the following order: washing solutions > preparation methods > synthesis temperature. Interestingly, the effects of synthesis condition on the crystalline structure of Ni/Fe were weak. The results may facilitate more effective application of Ni/Fe nanoparticles for degradation of BDE209.

Aerobic digestion is commonly used to achieve secondary sludge reduction in the small-size wastewater treatment plants. Nevertheless, secondary sludge degradation is usually restricted by the slow hydrolysis rate and low degradable percentage of secondary sludge. Here, we present an innovative approach using pretreatment of free ammonia (FA, i.e. NH3), a renewable chemical from wastewater, to improve the degradation of secondary sludge during aerobic digestion. The secondary sludge was degraded by 36 ± 4% (volatile solids (VS) basis) within 15 days of aerobic digestion while being pretreated at 300 mg NH3-N/L (pH 9.0; total ammonia nitrogen = 800 mg N/L) for 24 h, whereas only 23 ± 3% (VS basis) of the secondary sludge without FA pretreatment was degraded over the same period. Similarly, the production of inorganic nitrogen also increased from 27 ± 2 to 38 ± 2 mg N/g VS after implementing FA pretreatment, corroborating the idea that degradation of secondary sludge was effectively improved by FA pretreatment. Further analysis by model revealed that the improved hydrolysis rate and increased degradable percentage of secondary sludge were responsible for the enhanced sludge degradation in aerobic digestion. It was also found that FA pretreatment would produce an aerobic digestate with a better stability and dewaterability, as indicated by the lower degradable percentage of digestate and the decrease of capillary suction time from 38 ± 1 to 34 ± 1 s, respectively. Economic analysis indicates that the FA pretreatment approach would be economically favorable when the sludge transport and disposal cost is higher than $40/wet tone.

Abstract. This study investigated the role of representation strength of the prime in subliminal visuomotor priming in two experiments. Prime/target compatibility (compatible and incompatible) and preposed object type (jumbled lines, strong masking; and rectangular outlines, weak masking) were manipulated in Experiment 1. A significant negative compatibility effect (NCE) was observed in the rectangle condition, whereas no compatibility effect was found in the line condition. However, when a new variable, prime duration, was introduced in Experiment 2, the NCE was reversed with an increase in the prime duration in the rectangle condition, whereas the NCE was maintained in the line condition. This result is consistent with the claim that increasing the prime duration causes the prime representation to be too strong for inhibition in the rectangle condition but strong enough to reliably trigger inhibition in the line condition. The findings demonstrated that prime representation has a causal role in subliminal visuomotor priming.

Remediation of soil and groundwater contaminated with toxic metals has been a major environmental challenge for decades. Yet, cost-effective and sustainable in situ remediation technologies remain lacking. Over the last 15 years or so, an innovative in situ remediation strategy has shown promising by means of stabilized nanoparticles. Stabilized nanoparticles are prepared using novel stabilizers that facilitate the deliverability and transport of nanoparticles in the subsurface. This study reviews synthesis and characterization of some model stabilized nanoparticles and their application for remediation of metal-contaminated soil and water. Fate and transport of these stabilized nanoparticles in groundwater and soil are also examined. Lastly, this review identifies the key knowledge gaps such as lack of field data pertaining to the long-term effectiveness of the immobilized metals and impacts of the delivered nanoparticles on the biogeochemical conditions in the subsurface. The information may facilitate further development of this promising remediation technology.

Biochar supported carboxymethyl cellulose (CMC)-stabilized nanoscale iron sulfide (FeS) composite (CMC-FeS@biochar) was prepared and tested for immobilization of hexavalent chromium Cr(VI) in soil. Results of UV-vis and transmission electron microscopy (TEM) showed that the backbone of biochar suppressed the aggregation of FeS, resulting in smaller particle size and more sorption sites than bare FeS. The composite at a dosage of 2.5 mg per gram soil displayed an enhanced Cr(VI) immobilization efficiency (a 94.7% reduction in the toxicity characteristic leaching procedure (TCLP) based leachability and a 95.6% reduction in the CaCl2 extraction) compared to plain biochar and bare FeS. Sequential extraction procedure (SEP) and X-ray photoelectron spectroscopy (XPS) analysis suggested that CMC-FeS@biochar promoted the conversion of more accessible Cr (exchangeable and carbonate-bound fractions) into the less accessible forms (iron-manganese oxides-bound, organic material-bound, and residual fractions) to reduce the toxicity of Cr(VI) and that surface sorption and reduction were dominant mechanisms for Cr(VI) immobilization. CMC-FeS@biochar greatly reduced the bioavailability of Cr(VI) to wheat and earthworms (Eisenia fetida). Moreover, the application of CMC-FeS@biochar enhanced soil organic matter content and microbial activity. This work highlighted the potential of CMC-FeS@biochar composite as a low-cost, "green", and effective amendment for immobilizing Cr(VI) in contaminated soils and improving soil properties.

The present study investigated the roles of bottom-up mask-triggered inhibition and top-down inhibition in semantic categorization using the single negative priming (NP) paradigm. The masking (bottom-up) and ignore instructions (top-down, i.e., instructing participants to ignore the primes) were manipulated in Experiments 1-3 and Experiment 4, respectively. No priming was observed when only the masking was manipulated (Experiments 2 and 3), but NP was observed when a possible top-down ignore strategy (Experiment 1) or an ignore instruction (Experiment 4) was added. The results indicate that bottom-up mask-triggered inhibition cannot elicit semantic single NP by itself. However, top-down inhibition from an ignore instruction or ignore strategy is critical for triggering reliable semantic single NP. The findings suggest that semantic single NP originates from a push-pull mechanism by facilitating responses to unrelated trials and inhibiting responses to related trials. The experimental evidence also suggests that unconscious processes can be modulated by top-down control.

FeS-coated iron (Fe/FeS) magnetic nanoparticles were easily prepared, characterized, and applied for Cr(VI) removal in simulated groundwater. TEM, XRD, and BET characterization tests showed that FeS coating on the surface of Fe0 inhibited the aggregation of Fe0 and that Fe/FeS at a S/Fe molar ratio of 0.207 possessed a large surface area of 62.1 m2/g. Increasing the S/Fe molar ratio from 0 to 0.138 decreased Cr(VI) removal by 42.8%, and a further increase to 0.207 enhanced Cr(VI) removal by 63% within 72 h. Moreover, Fe/FeS inhibited the leaching of Fe, reducing the toxicity of the particles. Mechanistic analysis indicated that Fe0, Fe2 +, and S2 − were synergistically involved in the reduction of Cr(VI) to nontoxic Cr(III), which further precipitated as (CrxFe1-x)(OH)3 and Cr(III)-Fe-S. The process of Cr(VI) sorption by Fe/FeS (S/Fe = 0.207) was fitted well with a pseudo-second-order kinetic model, and the isotherm data were simulated by Langmuir isotherm model with a maximum sorption capacity of 69.7 mg/g compared to 48.9 mg/g for Fe0. Low pH and initial Cr(VI) concentration favored Cr(VI) removal. Continuous fixed bed column studies showed that simulated permeable reactive barriers (PRB) with Fe/FeS was considerably effective for in situ removal of Cr(VI) from groundwater. This study demonstrated the high potential of Fe/FeS for Cr(VI) immobilization in water, groundwater, and soil.

The importance of enhancing sludge dewaterability is increasing due to the considerable impact of excess sludge volume on disposal costs and on overall sludge management. This study presents an innovative approach to enhance dewaterability of anaerobic digestate (AD) harvested from a wastewater treatment plant. The combination of zero valent iron (ZVI, 0-4.0g/g total solids (TS)) and hydrogen peroxide (HP, 0-90mg/g TS) under pH3.0 significantly enhanced the AD dewaterability. The largest enhancement of AD dewaterability was achieved at 18mg HP/g TS and 2.0g ZVI/g TS, with the capillary suction time reduced by up to 90%. Economic analysis suggested that the proposed HP and ZVI treatment has more economic benefits in comparison with the classical Fenton reaction process. The destruction of extracellular polymeric substances and cells as well as the decrease of particle size were supposed to contribute to the enhanced AD dewaterability by HP+ZVI conditioning.

This review presents the state-of-the-art sludge reduction technologies applied in both wastewater and sludge treatment lines. They include chemical, mechanical, thermal, electrical treatment, addition of chemical un-coupler, and predation of protozoa/metazoa in wastewater treatment line, and physical, chemical and biological pretreatment in sludge treatment line. Emphasis was put on their effect on sludge reduction performance, with 10% sludge reduction to zero sludge production in wastewater treatment line and enhanced TS (total solids) or volatile solids removal of 5–40% in sludge treatment line. Free nitrous acid (FNA) technology seems good in wastewater treatment line but it is only under the lab-scale trial. In sludge treatment line, thermal, ultrasonic (< 4400 kJ/kg TS), FNA pretreatment and temperature-phased anaerobic digestion (TPAD) are promising if pathogen inactivation is not a concern. However, thermal pretreatment and TPAD are superior to other pretreatment technologies when pathogen inactivation is required. The new wastewater treatment processes including SANI®, high-rate activated sludge coupled autotrophic nitrogen removal and anaerobic membrane bioreactor coupled autotrophic nitrogen removal also have a great potential to reduce sludge production. In the future, an effort should be put on the effect of sludge reduction technologies on the removal of organic micropollutants and heavy metals.

Iron sulfide (FeS) nanoparticles were prepared with sodium carboxymethyl cellulose (CMC) as a stabilizer, and tested for enhanced removal of aqueous mercury (Hg(2+)). CMC at ≥0.03 wt % fully stabilized 0.5 g/L of FeS (i.e., CMC-to-FeS molar ratio ≥0.0006). FTIR spectra suggested that CMC molecules were attached to the nanoparticles through bidentate bridging and hydrogen bonding. Increasing the CMC-to-FeS molar ratio from 0 to 0.0006 enhanced mercury sorption capacity by 20%; yet, increasing the ratio from 0.0010 to 0.0025 diminished the sorption by 14%. FTIR and XRD analyses suggested that precipitation (formation of cinnabar and metacinnabar), ion exchange (formation of Hg0.89Fe0.11S), and surface complexation were important mechanisms for mercury removal. A pseudo-second-order kinetic model was able to interpret the sorption kinetics, whereas a dual-mode isotherm model was proposed to simulate the isotherms, which considers precipitation and adsorption. High mercury uptake was observed over the pH range of 6.5-10.5, whereas significant capacity loss was observed at pH6. High concentrations of Cl(-) (106 mg/L) and organic matter (5 mg/L as TOC) modestly inhibited mercury uptake. The immobilized mercury remained stable when preserved for 2.5 years at pH above neutral.

Effects of a model oil dispersant (Corexit EC9500A) on sorption/desorption of phenanthrene were investigated with two marine sediments. Kinetic data revealed that the presence of the dispersant at 18 mg/L enhanced phenanthrene uptake by up to 7%, whereas the same dispersant during desorption reduced phenanthrene desorption by up to 5%. Sorption isotherms confirmed that at dispersant concentrations of 18 and 180 mg/L, phenanthrene uptake progressively increased for both sediments. Furthermore, the presence of the dispersant during desorption induced remarkable sorption hysteresis. The effects were attributed to added phenanthrene affinity and capacity due to sorption of the dispersant on the sediments. Dual-mode models adequately simulated sorption isotherms and kinetic data in the presence of the dispersant. Water accommodated oil (WAO) and dispersant-enhanced WAO increased phenanthrene sorption by up to 22%. This information is important for understanding roles of oil dispersants on the distribution and transport of petroleum PAHs in seawater-sediments.

1-alky-3-methylimidazolium taurate ionic liquid, [Cnmim]Tau (n = 3,4) were synthesized by neutralization method and were confirmed by 1H NMR and 13C NMR. Standard addition method was applied to determine the densities, surface tensions and refractive indexes for [Cnmim]Tau (n = 3,4). By using Tong's vaporization enthalpy model, the vaporization enthalpies of [Cnmim]Tau (n = 3,4) and some other ILs were estimated. The association enthalpies, ΔAHm0 of them in gas phase were estimated. Combined gs with Lorentz–Lorenz equation, a semi-empirical surface tension predicting equation can be obtained. The surface tensions of [Cnmim][Tau](n = 3,4), some other ILs and some molecular liquids were predicted. The predicted values are highly similar with the corresponding experimental ones. In current work, we put forward a new method for predicting ΔlgCp,m0,which was used for [Cnmim]Tau (n = 3,4) and other ILs. Our results are in the same order magnitude with Verevkin's, but ours are relatively higher.

Sulfonated sucrose-derived carbon, glucose-derived carbon, and nut shell activated carbon (NSAC) catalysts were prepared and characterized by Fourier transform infrared spectroscopy (FT-IR) and X-ray photoelectron spectroscopy (XPS). FT-IR and XPS spectra showed that −SO3H groups could be introduced into the carbon precursors after the sulfonation treatment. Higher concentration of −SO3H groups in the sulfonated sucrose-carbon and glucose-carbon most likely accounts for their higher activities compared to sulfonated NSAC. Hydrolysis of microcrystalline cellulose was examined in a common ionic liquid, 1-butyl-3-methylimidazolium chloride ([BMIM]Cl), with the sulfonated carbon catalysts. Maximum yields of glucose (59%) and total products (80%, defined as the sum of glucose, cellobiose, and 5-hydroxymethylfurfural) could be obtained with sulfonated sucrose-carbon at 120 °C for 4 h. With a regeneration procedure, the catalyst could be reused.

This work investigated effects of a popular oil dispersant (Corexit EC9500A) on oxidation of phenanthrene and pyrene (two model polycyclic aromatic hydrocarbons) in Gulf coast seawater under simulated atmospheric ozone. The degradation data followed a two-stage pseudo-first order kinetics, a slower initial reaction rate followed by a much faster rate in longer time. The ozonation rate for pyrene was faster than that for phenanthrene. The presence of 18 and 180 mg/L of the dispersant inhibited the first-order degradation rate by 32-80% for phenanthrene, and 51-85% for pyrene. In the presence of 18 mg/L of the dispersant, the pyrene degradation rate increased with increasing ozone concentration, but decreased with increasing solution pH and temperature, while remained independent of ionic strength. For the first time, the results indicate that atmospheric ozone may play a significant role in the weathering of dispersed persistent oil components in natural and engineered systems.

Improving dewaterability of sludge is important for the disposal of sludge in wastewater treatment plants (WWTPs). This study, for the first time, investigated the Fe(II) activated oxidization processes in improving anaerobically digested sludge (ADS) dewaterability. The combination of Fe(II) (0–100 mg/g total solids (TS)) and persulfate (0–1,000 mg/g TS) under neutral pH as well as the combination of Fe(II) (0–100 mg/g TS) and hydrogen peroxide (HP) (0–1,000 mg/g TS) under pH 3.0 were used to examine and compare their effect on the ADS dewaterability enhancement. The highest ADS dewaterability enhancement was attained at 25 mg Fe(II)/g TS and 50 mg HP/g TS, when the CST (CST: the capillary suction time, a sludge dewaterability indicator) was reduced by 95%. In contrast, the highest CST reduction in Fe(II)-persulfate conditioning was 90%, which was obtained at 50 mg Fe(II)/g TS and 250 mg persulfate/g TS. The results showed that Fe(II)-HP conditioning was comparable with Fe(II)-persulfate conditioning in terms of highest CST reduction. Economic analysis suggested that the Fe(II)-HP conditioning was more promising for improving ADS dewaterability compared with Fe(II)-persulfate conditioning, with the saving being up to $65,000 per year in a WWTP with a population equivalent of 100,000.

Currently there are more than 40 centres in Canada that perform more than 65,000 percutaneous coronary interventions (PCIs) in a year. Considering the high volume of procedures and number of operators, the potential for variation in processes of care is high, and might lead to variation in the quality of care. As part of its quality initiative, the Canadian Cardiovascular Society convened a working group to develop a set of PCI Quality Indicators (QIs) that would be relevant, scientifically acceptable, and feasible to measure and report. The working group was comprised of clinical experts from across Canada and members of provincial and federal organizations involved in promoting the quality of health care. Using the Canadian Cardiovascular Society "Best Practices for Developing Cardiovascular Quality Indicators" methodology, a total of 23 QIs were proposed. Subsequent ranking and discussion led to the selection of 8 QIs. The selection and ranking of QIs were on the basis of clinical importance and relevance, scientific acceptability, and feasibility of their operationalization at a national level. The data definitions and technical notes of the QIs were refined after feasibility testing and Web consultation. Feasibility testing indicated that standardization and enhancements of knowledge infrastructure are essential to provide the comprehensive patient data necessary to evaluate the quality of PCI across Canada.

Fully stabilized magnetite (Fe3O4) nanoparticles were prepared with a water-soluble starch as a stabilizer and tested for removal of aqueous perfluorooctanoic acid (PFOA). The presence of starch at ≥ 0.2 wt% can fully stabilize 0.1 g/L as Fe of the Fe3O4 nanoparticles. The particle stabilization technique resulted in 2.4 times higher PFOA uptake. Fourier transform infrared spectra suggested that the main PFOA removal mechanism was inner-sphere complexation. Batch kinetic experiments revealed that the starch-stabilized nanoparticles facilitated a rapid PFOA uptake with a sorption equilibrium time of 30 min, and the sorption process followed a pseudo-second-order kinetic model. The Langmuir model was able to well interpret the adsorption isotherm, with a maximum adsorption capacity of 62.5 mg/g. Increasing pH from 4.7 to 9.6 led to a sharp increase (by 2.6 times) in PFOA uptake. The presence of 12 mg/L humic acid inhibited PFOA uptake by 96%, while effect of ionic strength (CaCl2 = 0–2 mmol/L) was negligible. The nanoparticles significantly reduced the biological toxicity of PFOA. The results demonstrated promise of starch-stabilized Fe3O4 nanoparticles as a “green” adsorbent for effective removal of PFOA in soil and groundwater.

In 2010, the Canadian Cardiovascular Society embarked on an initiative to develop pan-Canadian quality indicators (QIs) and standardized data definitions with the ultimate goal of monitoring, comparing, and contrasting national cardiovascular care and its outcomes. One of the first working groups to be established was tasked with identifying and then defining a set of QIs for atrial fibrillation/flutter (AF/AFL). The Canadian Cardiovascular Society "Best Practices for Developing Cardiovascular Quality Indicators" methodology was used to develop an initial catalogue of 25 QIs intended to measure critical issues around access, process, and outcomes relating to AF/AFL management. This list was subsequently pared down to 5 QIs felt to have the greatest relative importance for quality assurance and measurability so as to facilitate early adoption. Three of these QIs were finally selected to assess the feasibility of their measurement using existing administrative datasets. These were the number of patients with a diagnosis of nonvalvular AF/AFL at high risk of stroke (75 years or older, or CHADS 2 ≥ 2) receiving an oral anticoagulant, and the rates of stroke and major haemorrhage in patients with nonvalvular AF/AFL according to CHA 2 DS 2 -VASc score and anticoagulant use. Despite their clear importance in assessing AF/AFL care, none of these 3 QIs were found to be readily measurable across Canada using existing national datasets. Investment in new medical data infrastructure is required to facilitate regular monitoring of QIs to improve cardiovascular care.

The influence of antibody immune selective pressure on Newcastle disease virus (NDV) HN and F gene mutations was studied in cell cultures. NDV field strain TZ060107 was inoculated into chicken embryo fibroblast cells and continuously passaged with (group A) or without (group B) anti-NDV monospecific serum. Each group contained three independent passage series. HN and F genes were amplified and sequenced for the 10th, 20th, 30th, 40th and 50th generations of each serial passage, and compared with the original strain. The results demonstrated that increased HN gene mutations were observed in group A with the antibody than in group B without the antibody. The nonsynonymous (NS) to synonymous (S) mutations ratio was 6 for group A, significantly higher than 3.4 in group B. In group A with the antibody, there were five stable NS mutations in HN gene, three of which (related to aa#353, 521 and 568) were related to known epitopes. There were two stable NS mutations in F gene in group A, but no stable NS mutations in group B. The NS/S ratios of F gene were less than 2.5 for both groups A and B. Our results suggested that the antibody strongly influenced HN gene mutations, while the F gene was less influenced by the same antibody.

© 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim. Crystallizable, high-mobility conjugated polymers have been employed as secondary donor materials in ternary polymer solar cells in order to improve device efficiency by broadening their spectral response range and enhancing charge dissociation and transport. Here, contrasting effects of two crystallizable polymers, namely, PffBT4T-2OD and PDPP2TBT, in determining the efficiency improvements in PTB7-Th:PC 71 BM host blends are demonstrated. A notable power conversion efficiency of 11% can be obtained by introducing 10% PffBT4T-2OD (relative to PTB7-Th), while the efficiency of PDPP2TBT-incorporated ternary devices decreases dramatically despite an enhancement in hole mobility and light absorption. Blend morphology studies suggest that both PffBT4T-2OD and PDPP2TBT are well dissolved within the host PTB7-Th phase and facilitate an increased degree of phase separation between polymer and fullerene domains. While negligible charge transfer is determined in binary blends of each polymer mixture, effective energy transfer is identified from PffBT4T-2OD to PTB7-Th that contributes to an improvement in ternary blend device efficiency. In contrast, energy transfer from PTB7-Th to PDPP2TBT worsens the efficiency of the ternary device due to inefficient charge dissociation between PDPP2TBT and PC 71 BM.

Hydrochars produced from different feedstocks (sawdust, wheat straw, and corn stalk) via hydrothermal carbonization (HTC) and KOH modification were used as alternative adsorbents for aqueous heavy metals remediation. The chemical and physical properties of the hydrochars and KOH-treated hydrochars were characterized, and the ability of hydrochars for removal of heavy metals from aqueous solutions as a function of reaction time, pH, and initial contaminant concentration was tested. The results showed that KOH modification of hydrochars might have increased the aromatic and oxygen-containing functional groups, such as carboxyl groups, resulting in about 2-3 times increase of cadmium sorption capacity (30.40-40.78 mg/g) compared to that of unmodified hydrochars (13.92-14.52 mg/g). The sorption ability among different feedstocks after modification was as the following: sawdust wheat straw corn stack. Cadmium sorption kinetics on modified hydrochars could be interpreted with a pseudo-second order, and sorption isotherm was simulated with Langmuir adsorption model. High cadmium uptake on modified hydrochars was observed over the pH range of 4.0-8.0, while for other heavy metals (Pb(2+), Cu(2+), and Zn(2+)) the range was 4.0-6.0. In a multi-metal system, the sorption capacity of heavy metals by modified hydrochars was also higher than that by unmodified ones and followed the order of Pb(II) Cu(II) Cd(II) Zn(II). The results suggest that KOH-modified hydrochars can be used as a low cost, environmental-friendly, and effective adsorbent for heavy metal removal from aqueous solutions.

To review trends in drug therapy and concomitant outcomes of elderly heart failure patients in Ontario, Canada.Utilization of drug therapies, mortality, and rehospitalization rates from April 1992 to March 2000 were determined in 77,421 elderly (aged/=65 years), community-based heart failure patients using linked administrative databases. Treatment effects were identified from published meta-analyses and randomized trials. The effect of drug trends on mortality and morbidity were assessed based on their absolute treatment effects.From 1992 to 2000, angiotensin-converting enzyme inhibitor or angiotensin receptor blocker use increased from 58% to 62% (P = 0.001) while beta-blocker use increased from 6% to 22% (P0.001). There was a decrease in the use of treatments for which no survival advantage had been demonstrated in randomized trials, such as digitalis (49% to 35%, P0.001), Vaughan-Williams class I antiarrhythmic agents (3.5% to 1.4%, P0.001), and first-generation calcium antagonists (21.3% to 9.6%, P0.001). The trends in drug therapy were associated with a 2.8% reduction in age-, sex-, and comorbidity-adjusted 1-year mortality and a 4.1% reduction in 1-year hospitalization rates. The observed trends in therapy over time explained 37% of the decrease in mortality and 30% of the decrease in rehospitalization rates. The treatment effect from beta-blockers was most pronounced, explaining 30% of the decrease in mortality and 10% of the decrease in rehospitalization rates.During 1992 to 2000, mortality and morbidity improved among elderly patients with heart failure, with increased utilization of beta-blockers contributing most to the beneficial trends in outcomes.

This work explored the formation mechanism of marine oil snow (MOS) and the associated transport of oil hydrocarbons in the presence of a stereotype oil dispersant, Corexit EC9500A. Roller table experiments were carried out to simulate natural marine processes that lead to formation of marine snow. We found that both oil and the dispersant greatly promoted the formation of MOS, and MOS flocs as large as 1.6-2.1 mm (mean diameter) were developed within 3-6 days. Natural suspended solids and indigenous microorganisms play critical roles in the MOS formation. The addition of oil and the dispersant greatly enhanced the bacterial growth and extracellular polymeric substance (EPS) content, resulting in increased flocculation and formation of MOS. The dispersant not only enhanced dissolution of n-alkanes (C9-C40) from oil slicks into the aqueous phase, but facilitated sorption of more oil components onto MOS. The incorporation of oil droplets in MOS resulted in a two-way (rising and sinking) transport of the MOS particles. More lower-molecular-weight (LMW) n-alkanes (C9-C18) were partitioned in MOS than in the aqueous phase in the presence of the dispersant. The information can aid in our understanding of dispersant effects on MOS formation and oil transport following an oil spill event.

This work investigated effects of a prototype oil dispersant on solubilization, sorption and desorption of three model PAHs in sediment–seawater systems. Increasing dispersant dosage linearly enhanced solubility for all PAHs. Conversely, the dispersant enhanced the sediment uptake of the PAHs, and induced significant desorption hysteresis. Such contrasting effects (adsolubilization vs. solubilization) of dispersant were found dependent of the dispersant concentration and PAH hydrophobicity. The dual-mode models adequately simulated the sorption kinetics and isotherms, and quantified dispersant-enhanced PAH uptake. Sorption of naphthalene and 1-methylnaphthalene by sediment positively correlated with uptake of the dispersant, while sorption of pyrene dropped sharply when the dispersant exceeded its critical micelle concentration (CMC). The deepwater conditions diminished the dispersant effects on solubilization, but enhanced uptake of the PAHs, albeit sorption of the dispersant was lowered. The information may aid in understanding roles of dispersants on distribution, fate and transport of petroleum PAHs in marine systems.

This work investigated effects of a popular oil dispersant (Corexit EC9500A) on UV- or sunlight-mediated photodegradation of pyrene (a model polycyclic aromatic hydrocarbon) in seawater. The presence of 18 and 180mg/L of the dispersant increased the first-order photodegradation rate by 5.5% and 16.7%, respectively, and reduced or ceased pyrene volatilization. By combining individual first-order rate laws for volatilization and photodegradation, we proposed an integrated kinetic model that can adequately predict the overall dissipation of pyrene from seawater. Mechanistic studies indicated that superoxide radicals played a predominant role in pyrene photodegradation, and the dispersant enhanced formation of superoxide radicals. 1-Hydroxypyrene was the main intermediate regardless of the dispersant, suggesting that electrons were transferred from excited pyrene to oxygen. In the presence of 18mg/L of the dispersant, the photodegradation rate increased with increasing ionic strength and temperature, but decreased with increasing HA concentration, and remained independent of solution pH. The results are important in understanding roles of oil dispersants on environmental fate of persistent oil components in natural and engineered systems.

To express feruloyl esterase A from Aspergillus oryzae in Pichia pastoris expression system and study its hydrolysis function, explore the conditions and effects of purification for ferulic acid extracts by macroporos resin. Using the total RNA from A. oryzae CICC 40186 as the template, we amplified coding sequence AorfaeA encoding a mature feruloyl esterase A (AorFaeA) by RT-PCR technique. Then, the coding sequence AorfaeA was successfully expressed in Pichia pastoris GS115 mediated by an expression plasmid pPIC9K. The purified recombinant AorFaeA (reAorFaeA) showed one single band on SDS-PAGE with an apparent molecular weight of 39.0 kDa. The maximum activity of reAorFaeA to methyl ferulate, measured by high-performance liquid chromatography (HPLC), was 58.35 U/mg. Then, reAorFaeA was used to release ferulic acid from de-starched wheat bran in the presence of xylanase. The purification tests for ferulic acid from the enzymatic hydrolysate were carried out with preselected macroporous resins. The results showed that macroporous resin HPD-300 had much higher adsorption and desorption capacities. Ferulic acid could be quantitatively recovered by 50% of the eluent concentration at a flow speed of 1 mL/min. Under the purification condition, the recovery ratio of ferulic acid was 92%, and the content of ferulic acid was increased from 0.13% in the raw material to 10.55%. This work exploits the breakdown of ferulic acid by recombinant enzymeand provids a good strategy to its "green production".

Phosphorus is an essential nutrient for maintaining life. As a result, the natural sources of phosphorus are being exploited at an unsustainable pace. However, the release of phosphorus from wastewater effluent has been one of the major causes of eutrophication in receiving water bodies. Consequently, it has become increasingly compelling to remove and recover phosphorus from wastewater. This chapter reviews various conventional and emerging physical–chemical technologies for the removal and recovery of phosphorous, including chemical precipitation, crystallization, ligand exchange, adsorption, magnetic separation, and nanotechnologies. The principle, effectiveness, and applications of the process are discussed.

The 2010 Deepwater Horizon oil spill has spurred significant amounts of researches on fate, transport, and environmental impacts of oil and oil dispersants. This review critically summarizes what is understood to date about the interactions between oil, oil dispersants and sediments, their roles in developing oil spill countermeasures, and how these interactions may change in deepwater environments. Effects of controlling parameters, such as sediment particle size and concentration, organic matter content, oil properties, and salinity on oil–sediment interactions are described in detail. Special attention is placed to the application and effects of oil dispersants on the rate and extent of the interactions between oil and sediment or suspended particulate materials. Various analytical methods are discussed for characterization of oil–sediment interactions. Current knowledge gaps are identified and further research needs are proposed to facilitate sounder assessment of fate and impacts of oil spills in the marine environment.