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In this study, a Superhydrophobic (SH) surface with ultrahigh adhesive force and good anti-scratching property was created on elastomeric substrate by thiol-ene click chemistry. The elastomer substrate was prepared by solution mixing of styrene butadiene rubber (SBR), polar fluorinated monomer, multi-functional thiol, and photoinitiator. Then the silanized nano-silica was simply sprayed on the elastomer substrate to prepare the SH coating. Through UV irradiation, thiol-ene click reaction between multi-functional thiol and double bonds of SBR, fluorinated monomer and silanized nano-silica simultaneously occurs, leading to the crosslinking of SBR, the polymerization of fluorinated monomer, the graft of fluorinated monomer on silanized nano-silica, and the covalently bonding of fluorinated monomer with SBR substrate. As a result, the polymerized fluorinated monomer bonded silanized nano-silica is covalently bonded with the SBR substrate. Meanwhile, the silanized nano-silica forms the micro-nano structure on the substrate and the polymerized fluorinated monomer decreases the surface energy of the substrate. A stabilized SH coating with ultrahigh adhesive force (123 μN) to water was achieved. In addition, the SH surface shows strong interfacial bonding and a good anti-scratching property because of the covalent bonding of SH coating with the SBR substrate. This is a facile, simple and efficient method to fabricate SH coating on the elastomeric substrate, which may open a door to fabricate SH coating on other surfaces and provide more potential applications.

Cyanobacterial blooms continue to serve as one of the most serious global issues threatening water supply and human health. During cyanobacterial bloom season, a large •OH-yield equipment was developed and installed after coagulation settling in a 12000 ton/day drinking water treatment system in Xiamen, China. An •OH concentration of 7.76∼57.8 μmol/L was formed by using the oxygen activated species generated by strong ionisation discharge combining with the effect of water jet cavitation. •OH pre-treatment at a dose of 1.0 mg/L inactivated cyanobacterial blooms in the process of conveying bloom water within only 20s, which were then removed by sand filtration. Under SEM observation, dominant Microcystis sp. colonies connected by mucilage were dispersed into individuals that still retained the cell integrity, indicating no release of intracellular organic matter (IOM). According to a flow cytometry analysis, the main cause of •OH inactivation was the breakage of DNA strands. Meanwhile, the •OH-mineralized microcystin-LR was by breaking the C=C conjugated diene bond and crucial opening the persistent benzene ring to carboxylic acid m/z 158.0. During •OH pre-treatment of 1.0 mg/L and NaClO disinfection of 0.5 mg/L, all water quality indexes and disinfection by-product (DBP) contents complied with the Chinese Sanitary Standards for Drinking Water. Therefore, the •OH based on the strong ionisation discharge showed great prospect for large-scale drinking water treatment in the removal of cyanobacterial blooms while retaining cell integrity as well as the degradation of toxins.

A hydroxyl radical ( OH) ballast water treatment system (BWTS) was developed and applied to inactivate entrained organisms in a 10,000-ton oceanic ship, where OH was produced by a strong ionization discharge combined with a water jet cavitation effect. The calculated OH generation rate was 1373.4 μM min−1 in ballast water, which is much higher than that in other advanced oxidative processes such as photocatalysis. As a result, non-indigenous red tide algae were inactivated to meet the ballast water discharge standards ( OH inactivation. A risk assessment of the OH treatment system was conducted, and the ratios of predicted environmental concentrations to predicted no effect concentrations of all detected disinfection byproducts were less than 1, even at a worst-case oxidant concentration of 2.41 mg L−1. Ship ballast water treated using OH inactivation is safe for marine environments. Finally, the energy consumption and operational costs of the OH BWTS were found to be 0.033 kWh m−3 and CNY 0.03 m-3, respectively.

This work was carried out based on the principles of biological effectiveness and environmental acceptability of the International Maritime Organization (IMO). The non-native red tide organisms Prorocentrum donghaiense and Scrippsiella trochoidea were selected to examine ·OH inactivation to meet the IMO standard of ballast water discharge (

With diatomaceous earth as raw material and sodium aluminate as aluminum source by adopting TBAB template, ZSM-5 molecular sieve was synthesized by hydrothermal method of in-situ crystallization wh...

Disinfection byproducts (DBPs) generated by ballast water treatment have become a concern worldwide because of their potential threat to the marine environment. Predicting the relative DBP concentrations after disinfection could enable better control of DBP formation. However, there is no appropriate method of evaluating DBP formation in a full-scale ballast water treatment system (BWTS). In this study, multiple regression models were developed for predicting the dibromochloromethane (DBCM) and bromoform (TBM) concentrations produced by an emergency BWTS using field experimental data from ballast water treatments conducted at Dalian Port, China. Six combinations of independent variables [including several water parameters and/or the total residual oxidant (TRO) concentration] were evaluated to construct mathematical prediction formulas based on a polynomial linear model and logarithmic regression model. Further, statistical analyses were performed to verify and determine the appropriate mathematical models for DBCM and TBM formation, which were ultimately validated using additional field experimental data. The polynomial linear model with four variables (temperature, salinity, chlorophyll, and TRO) and the logarithmic regression model with seven variables (temperature, salinity, dissolved oxygen, pH, turbidity, chlorophyll, and TRO) exhibited good reproducibility and could be used to predict the DBCM and TBM concentrations, respectively. The validation results indicated that the developed models could accurately predict DBP concentrations, with no significant statistical difference from the measured values. The results of this work could provide a theoretical basis and data reference for ballast water treatment control in engineering applications of emergency BWTSs.

We isolated Pseudomonas putida (P. putida) strain 1A00316 from Antarctica. This bacterium has a high efficiency against Meloidogyne incognita (M. incognita) in vitro and under greenhouse conditions. The complete genome of P. putida 1A00316 was sequenced using PacBio single molecule real-time (SMRT) technology. A comparative genomic analysis of 16 Pseudomonas strains revealed that although P. putida 1A00316 belonged to P. putida, it was phenotypically more similar to nematicidal Pseudomonas fluorescens (P. fluorescens) strains. We characterized the diversity and specificity of nematicidal factors in P. putida 1A00316 with comparative genomics and functional analysis and found that P. putida 1A00316 has diverse nematicidal factors including protein alkaline metalloproteinase AprA and two secondary metabolites, hydrogen cyanide and cyclo-(l-isoleucyl-l-proline). We show for the first time that cyclo-(l-isoleucyl-l-proline) exhibit nematicidal activity in P. putida. Interestingly, our study had not detected common nematicidal factors such as 2,4-diacetylphloroglucinol (2,4-DAPG) and pyrrolnitrin in P. putida 1A00316. The results of the present study reveal the diversity and specificity of nematicidal factors in P. putida strain 1A00316.

When a gas–liquid turbulent jet with hydroxyl free radicals is jetted into a ballast water discharge pipe to kill the invasive microbes, there is a challenge for hydroxyl free radicals to contact a large number of microbes in ballast water. In this paper, the Eulerian–Eulerian two-equation model is employed to simulate the mixing process of gas–liquid being jetted into the ballast water crossflow. The results show that the upstream wall-surface vortices lead to counter-rotating scarf vortex pairs (CVSPs) at downstream in confined crossflow, which enhance the mixing process. However, it is hard for the gas in the downstream wall-surface jet to diffuse due to the fact that the CVSPs have no influence on the downstream wall-surface jet. Therefore, the higher the momentum ratio is, the lower the value of weighted coefficient of variation of gas volume fraction at outlet is, however, when the momentum ratio is constant, the weighted coefficient of variation first drops and then goes up with increasing diameter ratio.

With the physical method of micro-gap gas discharge, OH radicals were produced by the ionization of O2 in air and H2O in the gaseous state, in order to explore more effective method to treat the ship's ballast water. The surface morphology of Al2O3 dielectric layer was analysed using Atomic Force Microscopy (AFM), where the size of Al2O3 particles was in the range of 2 μm to 5 μm. At the same time, the biochemical effect of hydroxyl radicals on the introduced organisms and the quality of ship's ballast water were studied. The results indicate that the main reasons of cell death are lipid peroxide and damage of the antioxidant enzyme system in Catalase (CAT), Peroxidase (POD) and Superoxide dismutase (SOD). In addition, the quality of the ballast water was greatly improved.

With physical method of micro-gap gas discharge, a large amount of hydroxyl radical can be produced in 20t/h pilot-scale system using the ionization of O2 and H2O. In this paper, the effect of biochemistry of hydroxyl radicals on introduced organisms in ballast water was experimentally investigated. The results indicate that the contents of chlorophyl-a, chlorophyl-b, chlorophyl-c and carotenoid are decreased by 35%–64% within 8.0s and further to the lowest limit of test 5 minutes. In addition, the main reasons of cell death are the lipid peroxidation, the strong destruction to the monose, amylose, protein, DNA and RNA of cell, and damage in CAT, POD and SOD of antioxidant enzyme system.

A pilot-scale experiment of 20 t/h for the treatment of ship's ballast water is reported in this paper. When the concentration of the dissolved OH· was 0.68 mg/L during the experiment, the rate of destroying bacteria, mono-algae, protozoan reached 100% within 2.67 s. The effect of hydroxyl radicals on biochemical processes was also studied. The attenuation rate of photosynthesis pigment was 100%. And the main reason for the cells' death was the strong destruction of the monose, amylose, protein, DNA and RNA in the cells. As an advanced oxidation method, the procedure can destroy invasive marine species when a ship is in the process of discharging its ballast water.

In order to understand the differentiation of amino acid requirments in host-related populations of the brown planthopper (BPH), Nilaparvata lugens (Stal), we established three BPH populations by separately maintaining them on three rice varieties, i.e. TN1 (common susceptible control), Mudgo (containing resistant gene Bph 1) and ASD7 (containing resistant gene bph2) for over 30 generations, and then reared them on 20 holidic diets, each with distinct overall amino acids and ratio of essential amino acid (EAA) to nonessential amino acid (NEAA). The emergence rate, brachypter rate, nymphal duration and weight of newly molted adults were evaluated and compared. The results showed significant difference among the three populations in the effect of amino acid variation on BPH performance, ascending in an order of Mudgo population ASD7 population > TN1 pupulation. The results also indicated that the required optimum concentrations of overall amino acids by BPH populations on Mudgo and ASD7 were 4.0% -4.8% and 4.0%, respectively, higher than that of TN1 population (2.4% - 3.2%). In addition, it was found that Mudgo and ASD7 populations were more sensitive to the concentration of EAAs than TN1 population. We propose that there is substantial differentiation in responses to dietary amino acid conditions among different host-associated BPH populations and that such differentiation may be closely related to the induced virulence shift on resistant rice varieties.

The plasma synthesis of ammonia has been studied in a nitrogen–hydrogenplasma using a strong electric field discharge at ambient pressure andtemperature. With this method, N2 and H2 molecules are ionized anddissociated and a large number of free atoms, ions, and radicals areformed in a nonequilibrium plasma after inelastic collisions. The finalproduct was mainly ammonia, including a small amount of hydrazine. WhenMgO powder, used as a catalyst, was smeared on the surface of the electrodeplates, the yields of ammonia increased about 1.54–1.75 times andreached 5000 ppm (0.5% v/v). In this way, plasma synthesis of ammonia atambient pressure is realized and a new method is provided for inorganicsynthesis, which consumes little energy and simplifies the process.