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A novel PbO 2 /graphite felt electrode was constructed by electrochemical deposition of PbO 2 on graphite felt and characterized by X-ray powder diffraction (XRD) and scanning electron microscopy (SEM) analysis. The prepared electrode is a viable technology for inactivation of Escherichia coli , Enterococcus faecalis , and Artemia salina as indicator organisms in simulated ballast water treatment, which meets the International Maritime Organization (IMO) Regulation D-2. The effects of contact time and current density on inactivation were investigated. An increase in current density generally had a beneficial effect on the inactivation of the three species. E.faecalis and A.salina were more resistant to electrochemical disinfection than E. coli . The complete disinfection of E.coli was achieved in <8 min at an applied current density of 253 A/m 2 . Complete inactivation of E. faecalis and A.salina was achieved at the same current density after 60 and 40 min of contact time, respectively. A. salina inactivation follows first-order kinetics. [ABSTRACT FROM AUTHOR]

Abstract: Graphene oxide(GO)-activated carbon felt(ACF)(GO-ACF) composite was prepared by an electrophoretic deposition and subsequent thermal annealing. The structures of GO and GO-ACF were characterized by FT-IR, Raman spectra and XPS. The adsorption capacities for U(VI) from aqueous solution of ACF and GO-ACF were compared. The essential factors affected U(VI) adsorption such as initial pH, contact time and temperature were investigated. The adsorption is highly dependent on the solution pH. In addition, the adsorption isotherm and thermodynamics were investigated. The adsorptions of U(VI) from aqueous solution on GO-ACF were fitted to the Langmuir and, Freundlich adsorption isotherms. The adsorption of U(VI) could be well-described by Langmuir. The adsorption of U(VI) on ACF is remarkably improved by GO covalently bonding with ACF. The maximum sorption capacity of GO-ACF for U(VI) was evaluated to be 298 mg/g at pH 5.5, much higher than that of ACF (173 mg/g), suggesting the carboxyl functional groups of GO-ACF playing important roles in the sorption. Thermodynamic parameters further show that the sorption is an endothermic and spontaneous process. GO-ACF is a powerful promising sorbent for the efficient removal of U(VI) from aqueous solutions. [Copyright &y& Elsevier]

Abstract: Phylogenetic analysis suggested that the DENV1 strains isolated in the DF outbreak in Guangdong province in 2006 were likely to be imported from Southeast Asian. Specifically, viruses isolated from Shantou and Chaozhou were imported from Singapore; viruses isolated from Guangzhou, Yangjiang, and Foshan were imported from Thailand/Vietnam. Therefore, importation of DENV1 from Southeast Asia was an important contributory factor of the 2006 DF outbreak in Guangdong province. [Copyright &y& Elsevier]

Abstract: A novel chitosan–Ca3V10O28 complex membrane with sustained antimicrobial capability was prepared by the self-assembly of and chitosan, using Ca2+ as the linker. The complex membrane was characterized by means of FT-IR, TG-DSC, X-ray diffraction, SEM and elemental analysis. It is shown that Ca3V10O28 is evenly present on the surface of chitosan–Ca3V10O28 complex membrane in the form of amorphous crystal. The antibacterial trial shows that the two complexes examined have good antibacterial activity against Staphylococcus aureus and Eschercihia coli. The results indicate that the chitosan–Ca3V10O28 complex is an effective antimicrobial material and the membrane may be useful for wound dressing. [Copyright &y& Elsevier]

Abstract: Thiourea chitosan was prepared by the reaction of chitosan with ammonium thiocyanate in ethanol. Thiourea chitosan was characterized by FT-IR, 13C NMR, and elemental analysis; XPS confirmed that in thiourea chitosan–Ag+ complex, S atoms coordinated to silver ions and were the major electron donors; O atoms also coordinated to silver ions and they were another electron donors next to S atoms. N atoms did not take part in coordination. Thiourea chitosan–Ag+ complex overcomes the instability of Ag+. Antimicrobial activities of the complex was evaluated against six species of bacteria and molds. The complex showed a wide spectrum of antimicrobial activities, whose MIC values against bacteria were 20 times lower than those of chitosan, 100 times lower than those of sodium diacetate and 200 times lower than those of sodium benzoate, respectively; the complex has a better antibacterial activity than antifungal activity. [Copyright &y& Elsevier]

Microplastics and organophosphate esters are ubiquitous pollutants in the marine environment. However, their interactions are poorly understood. In the present study, the sorptions of tri-n-butyl phosphate (TnBP) and tris(2-chloroethyl) phosphate (TCEP) on polyethylene (PE) and polyvinyl chloride (PVC) microplastics in seawater were investigated. Results indicated that the first-order kinetic model and pseudo-second-order were suitable to describe PE and PVC microparticles for the adsorption of the two organophosphate esters, respectively. The adsorption capacity increased with the decrease in particle size. The highest adsorption capacity appeared at 15 °C. The equilibrium isotherms data for the adsorption of the two organophosphate esters on PVC and PE microplastics were best fitted with Freundlich isotherm model and Langmuir isotherm model, respectively. The pore-filling mechanism involved in the adsorption of TnBP and TCEP on PVC microplastics and the monolayer coverage was the predominant mechanism for the adsorption of TnBP and TCEP on PE microplastics. • Adsorption of two OPEs on microplastics was first studied. • Microplastics size and temperature had significantly effects on the sorption of OPEs. • Kinetics and isotherm were clarified for the adsorptions of OPEs on microplastics. • Adsorption mechanisms were related to physical-chemical properties of OPEs and MPs. [ABSTRACT FROM AUTHOR]

A new adsorbent was developed and investigated for removing radioactive iodide (I−) from wastewater. The HDTMA 12.5% -geopolymers prepared with the optimum hexadecyltrimethylammonium bromide (HDTMABr)/mekaoline mass ratio of 0.125 were used as adsorbents to remove I− from simulated radioactive wastewater. The HDTMA-geopolymers were prepared by adding HDTMABr into metakaolin-based geopolymeric slurry and characterized using FT-IR, SEM, XRD. The adsorption equilibrium isotherms data of iodide by HDTMA 12.5% -geopolymer was better fitted with Freundlich isotherm model and the adsorption capability was found as 36.1 mg g−1. The adsorption kinetics was found to follow the pseudo-second-order kinetics. The thermodynamic analysis revealed that the adsorption process was endothermic and favorable. Limited influence was found on the adsorption process by pH and other large concentrations of competitive anions, such as Cl−, CO 3 2−, SO 4 2− and NO 3 −. This study demonstrated a new low-cost and efficient adsorbent for removing radioactive I− from wastewater. • HDTMABr modified geopolymers as adsorbents were firstly used to remove I−. • Sorption capacities of I− were remarkably enhanced with HDTMABr modification. • The anion exchange mechanism of HTDMA-geopolymer for I− adsorption was proposed and verified. [ABSTRACT FROM AUTHOR]

Abstract: The Ag3PO4/Bi2WO6 hierarchical heterostructures were prepared by a combination of hydrothermal technique and in situ precipitation method for the first time. The Ag3PO4/Bi2WO6 hierarchical heterostructures displayed enhanced visible-light photocatalytic activity against phenol. The enhanced photocatalytic activity could be attributed to the effective separation of photogenerated carriers driven by the photoinduced potential difference generated at the Ag3PO4/Bi2WO6 heterojunction interface. Repetitive tests showed that the Ag3PO4/Bi2WO6 hierarchical heterostructures maintained high catalytic activity over several cycles, and it had a better regeneration capability under mild conditions. [Copyright &y& Elsevier]

Abstract: We describe here a novel approach to the high efficient fabrication of chitosan micropowder by combining radiation technique and jet pulverization. The radiation dose is at 100–300kGy. Size of microparticles in ethanol dispersion determined by dynamic laser scattering (DLS) is in the range of 5–20μm, depending on the radiation dose and degree of deacetylation (DD). However, Scanning electron micrography (SEM) measurement shows a size range of 0.1–10μm. FTIR spectra indicate that chemical structure of the micropowder is retained, while the decomposition temperature measured decreases slightly as compared to the control. [Copyright &y& Elsevier]

• We exploit the characteristics of food delivery routes. • We develop an improved inverse reinforcement learning method for route planning. • We develop an approach to conduct route recommendation in the absence of road network information. In China, rapid development of online food delivery brings massive orders, which relies heavily on deliverymen riding e-bikes. In practice, actual delivery routes of most orders are not the same as the system recommended routes, and the road network information for some areas is outdated or incomplete. In this research, we develop a deep inverse reinforcement learning (IRL) algorithm to capture deliverymen's preferences from historical GPS trajectories and recommend their preferred routes. Considering the characteristics of food delivery routes, we employ Dijkstra's algorithm instead of value iteration, to determine the current policy and compute the gradient of IRL. Moreover, we plan routes at the presence and absence of road network information, providing accurate navigation when road network information is unknown. Numerical experiments on real delivery trajectories provided by Meituan-Dianping Group show that our approach improves F 1 - score distance by 8.0 % and 6.1 % at the presence and absence of road network information, respectively. [ABSTRACT FROM AUTHOR]

Route planning is widely used in areas such as car navigation. For some popular mobility services such as meal delivery and online car-hailing, planning routes that closely follow drivers' actual routes is important. Some existing methods propose that drivers plan routes in two steps: first identify intermediate waypoints on the route that connects the origin and destination; then find a series of sub-routes between successive waypoints, respectively. In this research, we advance these methods as follows: (1) We generalize the two-step process to a divide-and-conquer framework. We first identify intermediate waypoints between the origin and the destination and decompose the route planning problem into several sub-problems, whose intermediate waypoints are identified again. We recursively repeat this process until no more waypoints are identified for all the sub-problems; and (2) Unlike existing studies that identify waypoints solely based on the travel frequency of links, we propose a Graph Attention Network (GAT) Enhanced Insertion Transformer (GEIT) model for waypoint identification. GEIT model uses an Insertion Transformer to learn the relationship among links, which can better capture the mobility pattern embedded in historical routes. In addition, by incorporating a GAT to enhance our link representations, our model spreads the learned information along the road network to address the trajectory sparseness problem. Numerical experiments on a real-world trajectory data set demonstrate that the routes planned by our model show fewer deviations from the actual routes compared with state-of-the-art route planning algorithms. • We generalize the two-step hierarchical method into a divide-and-conquer framework. • We propose a Graph Attention Network Enhanced Insertion Transformer model. • We show that our model outperforms state-of-art methods. [ABSTRACT FROM AUTHOR]

• The prevalence of human pegivirus type 1 (HPgV-1) in hematopoietic stem cell transplantation (HSCT) patients is 18.6%. • The prevalence of HPgV-1 is higher in HSCT patients than in healthy blood donors. • The predominant genotype of HPgV-1 in HSCT patients is genotype 3. • More transfusions were given to HSCT patients with RNA test conversions (negative to positive) than to those without this conversion. To investigate the prevalence, risk factors, and genotypes of human pegivirus type 1 (HPgV-1) in hematopoietic stem cell transplantation (HSCT) patients. One hundred and eighty-eight HSCT patients and 694 healthy blood donors were investigated retrospectively, including their demographic information and HPgV-1 infection status. When compared with healthy blood donors, a significantly higher HPgV-1 prevalence (18.6% vs. 2.3%) and a high risk of HPgV-1 infection (odds ratio 9.7) were observed in HSCT patients (p < 0.05). The number of transfusions in patients with RNA test conversions (negative to positive) was significantly higher than the number in patients without conversions (negative to negative) (median 10 vs. 1) (p < 0.05). Although HPgV-1 infection is independent of age, sex, blood type, hepatitis B virus infection, hepatitis C virus infection, marriage status, and type of hematological malignancy (p > 0.05), race might be a risk factor for infection (p < 0.05). The great majority (95.7%) of HPgV-1-positive patients were infected with genotype 3. HPgV-1 is highly prevalent in HSCT patients, and blood transfusions can significantly increase the risk of HPgV-1 infection. Thus, HPgV-1 screening is recommended in HSCT patients to reduce the potential impact of infection on survival, as well as in their blood and stem cell donors to reduce the risk of infection after transfusions, unless the beneficial effects of HPgV-1 infection in immunocompromised patients are clearly confirmed. [ABSTRACT FROM AUTHOR]