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Sulfa antibiotics (SAs) and quorum-sensing inhibitor (QSI) may pose potential ecological risks because mixed using of them has been proposed to inhibit bacteria from generating antibiotic resistance. This study investigated the time-dependent hormesis of single and binary mixtures of QSI and SAs of Vibrio fischeri (V. fischeri) for 0-24 h. Although the low-dose SAs stimulated the expression of LuxR protein, the high-dose SAs could inhibit bacteria growth by competitively binding to dihydropteroate synthase. Moreover, AinR protein was bound to Benzofuran-3(2H)-one (B3O) with low concentration, thus the N-octanoyl homoserine lactone signal molecules (C8) has chance to bind to LuxR protein to promote light emission. The hormesis effect induced by the mixtures could be deduced that SAs promoted the expression of LuxR protein and B3O increases the chance of C8 binding to LuxR. Our findings facilitate new insight into the mechanistic study of hormesis and ecological risks of the chemical mixtures.

A renewable, amphoteric functionalized mesoporous silica (AG-SBA-15) was synthesized with a two-steps process: firstly, aluminum atoms was incorporated into the framework of SBA-15 and then melamine-based dendrimers groups were anchored onto the Al-substituted SBA-15. The amphoteric AG-SBA-15 kept an ordered hexagonal mesostructure after the functionalization and regeneration processes and exhibited an excellent performance for simultaneous removal of Cu(II) cations and Cr 2 O 7 2− metalloid anions from aqueous solution, with the maximum adsorption capacity of 2.216 mmol/g Cu(II) and 3.305 mmol/g Cr 2 O 7 2− , respectively. Batch adsorption experiments results indicated that the optimized pH value for simultaneous removal of Cu(II) and Cr 2 O 7 2− was 5.0. The adsorption rate was extremely fast and the equilibrium reached within 30 min. The adsorption of Cu(II) and Cr 2 O 7 2− by AG-SBA-15 were fitted better to Langmuir than Freundlich Model and thermodynamic parameters revealed the spontaneous and exothermic nature of the adsorption. Reusability studies of AG-SBA-15 were carried out by 5 repeated adsorption–desorption cycles and the results confirmed that AG-SBA-15 could be easily reused with little loss in removal efficiency. Furthermore, simultaneous removal mechanism of Cu(II) and Cr 2 O 7 2− by AG-SBA-15 was proposed by X-ray photoelectron spectroscope analysis (XPS), which revealed that Cu(II) was adsorbed by a combination of electrostatic interaction, while Cr(VI) could be immobilized by reduction.

A collectable and non-sintered material prepared as hollow cylindrical shaped pellet from dry desulfurization slag (FGD ash) and ordinary Portland cement (OPC) for wastewater treatments is tested. The characteristic results of powder X-ray diffraction (XRD) and infrared absorption spectroscopy (IR) show that –OH, CO32−, SO32− and SO42− are the possible functional groups responsible for Pb uptake. Adsorption data indicate that Pb removal is pH dependent and optimal at pH 6, with a very rapid initial removal that reaches equilibrium in about 90 min. A maximum removal of 99.2% is seen for 5 mg/L (pH of 6); higher initial Pb concentrations reduce overall removal efficiencies, but generate higher surface loadings. Adsorption process correlates well with both Langmuir and Freundlich models, although the Langmuir isotherm is more favored, providing a maximum adsorption capacity ( Q m ) of 130.2 mg/g (13 wt%). Pseudo-second order rate kinetic model best describes the Pb removal, and calculated R L values between 0 and 1, indicate a favored adsorption process that is chemisorption limited. SEM and EDAX analysis of the surface and fracture surface show that Pb occurs as surface precipitates and that Pb is not distributed to the inner core of the pellet. This study demonstrates that dry FGD ash could be successfully used for wastewater Pb removal.

Laser range-gated imaging has great potentials in remote night surveillance with far detection distance and high resolution, even if under bad weather conditions such as fog, snow and rain. However, the field of view (FOV) is smaller than large objects like buildings, towers and mountains, thus only parts of targets are observed in one single frame, so that it is difficult for targets identification. Apparently, large FOV is beneficial to solve the problem, but the detection range is not available due to low illumination density in a large field of illumination matching with the FOV. Therefore, a large field-of-view range-gated laser imaging is proposed based on image fusion in this paper. Especially an image fusion algorithm has been developed for low contrast images. First of all, an infrared laser range-gated system is established to acquire gate images with small FOV for three different scenarios at night. Then the proposed image fusion algorithm is used for generating panoramas for the three groups of images respectively. Compared with raw images directly obtained by the imaging system, the fused images have a larger FOV with more detail target information. The experimental results demonstrate that the proposed image fusion algorithm is effective to expand the FOV of range-gated imaging.

Underwater range-gated laser imaging (URGLI) still has some problems like un-uniform light, low brightness and contrast. To solve the problems, a variant of adaptive histogram equalization called contrast limited adaptive histogram equalization (CLAHE) is proposed in this paper. In experiment, using the CLAHE and HE to enhance the images, and evaluate the quality of enhanced images by peak signal to noise ratio (PSNR) and contrast. The result shows that the HE gets the images over-enhanced, while the CLAHE has a good enhancement with compressing the over-enhancement and the influence of un-uniform light. The experimental results demonstrate that the CLAHE has a good result of image enhancement for target detection by underwater range-gated laser imaging system.