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C66H34N4O12F12Er2, triclinic, P1̄ (no. 2), a = 11.8934(5) Å, b = 12.0041(4) Å, c = 12.4578(5) Å, α = 68.718(4)°, β = 64.205(4)°, γ = 87.053(3)°, V = 1480.09(12) Å3, Z = 1, R gt(F) = 0.0326, wR ref(F 2) = 0.0626, T = 293(2) K.

Background: Epilepsy is a chronic, complex, unprovoked, and recurrent disorder of the nervous system that affected several people worldwide. Phyllanthus amarus (PA) has been documented to have neuroprotective potential. Aim: To evaluate the potential of standardized extract of PA and its possible mechanism of action against the Pentylenetetrazol (PTZ)-induced convulsion and kindling associated post-ictal depression in experimental mice. Materials and Methods: Phyllathin was isolated from methanolic extract of PA and well-characterized using HPTLC, ESI-MS/MS, and LC/MS. Phyllathin containing a standardized extract of PA (50, 100, and 200 mg/kg) was administered in convulsed and kindled mice, followed by an assessment of various parameters. Results: The spectral analysis confirmed the molecular formula and weight of phyllanthin as C24H34O6 and 418.2342 Da. PA (100 and 200 mg/kg) significantly ameliorated PTZ-induced ( p < 0.05) duration, onset of tonic-clonic convulsion, and mortality in mice. It also significantly attenuated ( p < 0.05) PTZ-induced kindling in mice. Alteration in brain GABA, dopamine, and glutamate, Na+K+ATPase, Ca+2-ATPase activities, and oxido-nitrosative stress in kindled mice was significantly restored ( p < 0.05) by PA treatment. It also significantly ( p < 0.05) down-regulated brain mRNA expressions of NF-κB, TNF-α, IL-1β, COX-2, and TLR-4. Histological aberrations induced by PTZ in the brain of a kindled rat was significantly ( p < 0.05) ameliorated by PA. Conclusion: Phyllanthin containing a standardized extract of PA exerts its antiepileptic potential via balancing excitatory (glutamate) and inhibitory (GABA) brain monoamines, voltage-gated ion channels (Na+K+/Ca+2-ATPase) and inhibition of NF-κB/TLR-4 pathway to ameliorate neuroinflammation (TNF-α, IL-1β, and COX-2) in experimental mice.

A novel acentric metal borosilicate, Ba4Bi2(Si8–xB4+xO29) (x = 0.09), exhibits the strongest NLO effects in borosilicates., A new acentric metal borosilicate, namely Ba4Bi2(Si8–xB4+xO29) (x = 0.09), has been synthesized by a standard solid-state reaction. The title compound crystallizes in noncentrosymmetric (NCS) space group I4[combining macron]2m with lattice parameters a = 11.0254(4) Å and c = 10.3961(9) Å. Structure refinements indicate that mixing of B atoms and Si atoms exists for a few atomic sites. In the “ideal” Ba4Bi2(Si8B4O29), BO4 or SiO4 tetrahedra are inter-connected by corner-sharing to cyclic B4O12 or Si4O12 units. These B4O12 and Si4O12 units are further interconnected via corner-sharing to an “ideal” [Si8B4O29]14– 3D network. The Ba2+ and Bi3+ act as the counter cations and are located at the cavities of the structure. Ba4Bi2(Si8–xB4+xO29) (x = 0.09) melts incongruently at a high temperature of 929 °C. Powder second-harmonic generation (SHG) measurements reveal that Ba4Bi2(Si8–xB4+xO29) (x = 0.09) is a type I phase-matching compound with a good SHG response of about 5.1 times that of KDP (KH2PO4), which is the highest among the borosilicates reported so far. The SHG source has been studied by DFT theoretical calculations. Our preliminary results indicate that Ba4Bi2(Si8–xB4+xO29) (x = 0.09) is a new second-order nonlinear-optical crystalline material candidate.

Mealworms from three different regions: Guangzhou, Tai'an and Shenzhen, were fed with three commonly used microplastics of polystyrene (PS), polyvinyl chloride (PVC) and low-density polyethylene (LDPE) for 1 month under favorable conditions, respectively. The survival rate and average weight of mealworms, the mass loss of microplastics and the production of frass were recorded every 4 days. Samples collected were characterized by X-ray diffraction, fourier transform infrared spectroscopy, thermogravimetric analyzer and gel permeation chromatography. The results showed that mealworms from Tai'an and Shenzhen could effectively metabolize the whole microplastics tested, while those from Guangzhou could only metabolize PS and LDPE. Besides, LDPE could be degraded by mealworms from Tai'an and Shenzhen, while those from Guangzhou showed no such capability, indicating that mealworms from different regions present different metabolism effects. Furthermore, PS and LDPE are more likely to be metabolized compared with PVC.

A bioelectrochemical sensor (BES) was constructed for toxicity assessment of copper in contaminated domestic sewage. Electrochemically active bacteria (EAB), whose growth was supported by the bioenergy generated from an in situ metallurgical process, functioned as the sensing elements. The external resistance of metallurgical BES was optimized based on linear sweep voltammetry analysis. The stabilized BES was utilized to monitor the copper toxicity in real wastewater. During the less than 1-h sensing period, copper concentration ranging from 1 to 5 mg L−1 could be detected. A power output of around 100 Wh (kg Cu)−1 and metallic copper resource were obtained simultaneously. This study demonstrated that the highly active EAB species enriched in metallurgical BES could be a promising candidate for rapid and reliable evaluation of copper toxicity in real domestic wastewater.

Disposal of nitrogen nutrient and excess sludge is a keen concern in wastewater treatment plants. This study describes a simple method of preparing an economical adsorbent, i.e., magnetic excess sludge (MES) by compounding the excess sludge with Fe3O4 nanoparticles. Ammonia–nitrogen removal from simulated wastewater was investigated by using the MES as an adsorbent. The MES had an adsorption efficiency of up to 90% for ammonium removal. Highly efficient separation of adsorbed ammonium on the MES could be magnetically separated from wastewater within 30 s. The operating conditions for ammonium adsorption were optimized at MES dose of 20 g/L, initial ammonium concentration of 45 mg/L and operating temperature of 298–308 K. The equilibrium data of ammonium adsorption on the MES showed a good agreement with the Langmuir isotherm, while the kinetic data were best fitted by the pseudo-second-order model. FTIR analysis indicated that various functional groups, such as hydroxyl and carboxyl groups, existed on the surface of the MES and contributed to the excellent capability for ammonium adsorption. These results suggest that the MES is a promising candidate for removing ammonium from wastewater and recycling excess sludge to ease its disposal at low cost.

A straw cellulose-cerium oxide (SC-CeO2) nanocompsite has been synthesized through a hydrothermal method. Before this, the SC is oxidized and functionalized by a 2,2,6,6-tetramethylpiperidine-1-oxyl radical (TEMPO)-mediated oxidation. The as-obtained SC displays carbon nanotube-like nanocellulose. When composited with CeO2, the nanocellulose grows on the surface of CeO2. The synergistic effect between SC and CeO2 results in an efficient separation of photogenerated carriers in the SC and CeO2 coupling system. It is confirmed in this work that the SC-CeO2 nanocomposite has good visible light-induced photocatalytic activity on reduction of aqueous Cr(VI) under acid condition (pH 4–6). More than 95% Cr(VI) (3–5 ppm) can be reduced under visible light irradiation for 60 min. Photocatalyst dosage and Cr(VI) concentration affect the conversion rate greatly.

A series of N-(furan-2-ylmethyl)-1H-indole-3-carboxamide derivatives(6a—6p) was designed and synthesized for developing novel indole scaffolds as anticancer agents targeting the epidemal growth factor receptor (EGFR), and the cytotoxic activities of the target compounds were evaluated against three EGFR high-expressed cancer cell lines[human lung adenocarcinoma cell line(A549), Henrietta Lacks strain of cancer cell line(HeLa) and human colorectal cancer cell line(SW480)], one EGFR low-expressed cell line(human liver cancer cell line, HepG2) and one human liver normal cell line(HL7702) using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) assay. Some target compounds exhibited potent anticancer activities against A549, HeLa, SW480 and weak activities on HepG2, which signifies that the target compounds are likely to be EGFR inhibitors as expected. And they showed weak cytotoxic effects on HL7702, which implies the target compounds are probably to be of low toxicity against normal cells. Among them, the target compound 1-ethyl-N-(furan-2-ylmethyl)-5-{2-{[2-(2-methoxyphenoxy)ethyl]amino}-2-oxoethoxy}-2-methyl-1H-indole-3-carboxamide(6p) with 2-{[2-(2-methoxyphenoxy)ethyl]-amino}-2-oxoethoxy group at the C5 position of the N-(furan-2-ylmethyl)-1H-indole-3-carboxamide scaffold exhibited the most potent anticancer activity. Also the binding interaction of the target compound 6p with EGFR was explored by molecular docking. Conclusively, the novel indole scaffold may be beneficial to investigate new anticancer agents for targeting the EGFR.

A TEMPO-oxidized straw cellulose-doped yttrium oxide (Y 2 O 3 -SC) was obtained via a hydrothermal method in the present work. The Y 2 O 3 -based materials were fully characterized. Plate count method was used to investigate the antibacterial activity of the Y 2 O 3 -SC composite. Antibacterial tests showed that Y 2 O 3 and its nanocomposites exhibited good antibacterial activities toward both Gram-negative Escherichia coli ( E. coli ) and Gram-positive Staphylococcus aureus ( S. aureus ). Besides, visible light irradiation could improve antibacterial activity of the Y 2 O 3 -SC. Antibacterial mechanism was also presented based on the results of scavengers experiment. Considering the excellent antibacterial activity of Y 2 O 3 -SC, the silver nanoparticle free nanocomposite is a promising candidate for cleaning the microbial contamination.

C48H30N4O12F12Cu3, monoclinic, P21/n (no. 14), a = 12.9112(5) Å, b = 28.1127(6) Å, c = 14.2324(5) Å, β = 110.665(4)°, V = 4833.5(3) Å3, Z = 4, R gt(F) = 0.0489, wR ref(F 2) = 0.1108, T = 173(10) K.

This study evaluated uranium sequestration performance in iron-rich (30 g/kg) sediment via bioreduction followed by reoxidation. Field tests (1383 days) at Oak Ridge, Tennessee demonstrated that uranium contents in sediments increased after bioreduced sediments were re-exposed to nitrate and oxygen in contaminated groundwater. Bioreduction of contaminated sediments (1200 mg/kg U) with ethanol in microcosm reduced aqueous U from 0.37 to 0.023 mg/L. Aliquots of the bioreduced sediment were reoxidized with O2, H2O2, and NaNO3, respectively, over 285 days, resulting in aqueous U of 0.024, 1.58 and 14.4 mg/L at pH 6.30, 6.63 and 7.62, respectively. The source- and the three reoxidized sediments showed different desorption and adsorption behaviors of U, but all fit a Freundlich model. The adsorption capacities increased sharply at pH 4.5 to 5.5, plateaued at pH 5.5 to 7.0, then decreased sharply as pH increased from 7.0 to 8.0. The O2-reoxidized sediment retained a lower desorption efficiency at pH over 6.0. The NO3−-reoxidized sediment exhibited higher adsorption capacity at pH 5.5 to 6.0. The pH-dependent adsorption onto Fe(III) oxides and formation of U coated particles and precipitates resulted in U sequestration, and bioreduction followed by reoxidation can enhance the U sequestration in sediment.

In this study, bacterial mercury (Hg) methylation was investigated under the influence of red-tide algae of Skeletonema costatum (S. costatum). The distribution and speciation of total mercury (THg) and methylmercury (MeHg) were profiled by employing Geobacter metallireducens (G. metallireducens GS-15) as the methylating bacteria. G. metallireducens GS-15 showed different capabilities in methylating different inorganic forms of Hg(II) (HgCl2) and Hg(II)-Algae (HgCl2 captured by S. costatum) to MeHg. In the absence of S. costatum, a maximum methylation efficiency of 4.31 ± 0.47% was achieved with Hg(II) of 1–100 μg L−1, while accelerated MeHg formation rate was detected at a higher initial Hg(II) concentration. In the presence of S. costatum, there were distinct changes in the distribution of THg and MeHg by altering the bioavailability of Hg(II) and Hg(II)-Algae. A larger proportion of THg tended to be retained by a higher algal biomass, resulting in decreased methylation efficiencies. The methylation efficiency of Hg(II) decreased from 3.01 ± 0.10% to 1.01 ± 0.01% with 10-mL and 250-mL algal media, and that of Hg(II)-Algae decreased from 0.83 ± 0.13% to 0.22 ± 0.01% with 10-mL and 250-mL Hg(II)-Algae media. Fourier transform infrared spectrometry, surface charge properties and elemental compositions of S. costatum were used to infer that amine, carboxyl and sulfonate functional groups were most likely to interact with Hg(II) through complexation and/or electrostatic attraction. These results suggest that red-tide algae may be an influencing factor on bacterial Hg methylation in eutrophic water bodies.

Ideonella sp. TH17, an autotrophic hydrogen-oxidizing bacterium (HOB), was successfully enriched and isolated from activated sludge in a domestic wastewater treatment plant (WWTP). Batch experiments were conducted to identify the cell growth and ammonium (NH4+-N) removal, and to verify the pathways of nitrogen utilization under different conditions. At a representative NH4+-N concentration of 100 mg/L in domestic wastewater, it was the first time that a HOB strain achieved a nearly 100% ammonium removal. More than 90% of NH4+-N was assimilated to biomass nitrogen by strain TH17. Only a little of N2 (

C34H24Cu2F8N4O8, monoclinic, P21/n (no. 14), a =13.074(3) Å, b = 20.229(4) Å, c = 14.419(3) Å, β = 108.889(2)°, V = 3608.2(12) Å3, Z = 4, R gt(F) = 0.0512, wR ref(F 2) = 0.1465, T = 296(2) K.

Acyl-homoserine lactone (AHL)-based quorum sensing (QS) in the anaerobic ammonium oxidizing (anammox) consortia has attracted increasing attention. However, AHL synthase in anammox bacteria and the relationship between AHL synthetic genes and anammox activity are still not clear because anammox bacteria have not been isolated from the consortia. Two novel synthases of AHLs (JqsI-1 and JqsI-2), which are HdtS-type rather than the widely studied LuxI-type, were identified in anammox bacteria Candidatus Jettenia caeni and synthesized four AHLs. There was a correlation between AHL concentration, in situ transcriptional expression of the AHL synthase genes (jqsI-1 and jqsI-2) and genetic marker of anammox activity (hydrazine synthase gene, hzsA). And AHL add-back studies demonstrated that AHL influence the expression of hzsA to regulate anammox bacterial activity. This study provides insight into the QS communication pathway of anammox bacteria for wastewater treatment.

Algae and mercury (Hg) are ubiquitous in marine environments. In this study, we investigated the effects of a typical marine algae of diatom Skeletonema costatum on Hg methylation by an iron-reducing bacterium of Geobacter sulfurreducens (G. sulfurreducens) PCA. In the absence of Skeletonema costatum, the bacterial MeHg production rate maximized at 104.06 ± 11.7 ng L−1 h−1 with a high Hg level, while the highest methylation efficiency was achieved at a low Hg concentration. The existence of Skeletonema costatum greatly inhibited the capability of G. sulfurreducens PCA to methylate Hg. With the increase in algal biomass, there was a significant mitigation of MeHg formation and Hg0 release, leaving a considerable proportion of immobilized Hg2+ species (up to 47%) associated with algal cell materials. These results suggest that marine algae are crucial in determining the bioavailability of Hg contaminants and the methylating potential of G. sulfurreducens PCA.

C23H23N3O6, monoclinic, P21/c (no. 14), a = 11.235(6) Å, b = 11.251(7) Å, c = 17.814(10) Å, β = 98.872(12)°, V = 2225(2) Å3, Z = 4, R gt(F) = 0.0581, wR ref(F 2) = 0.1590, T = 296(2) K.

Using sodium alginate hydrogel as skeleton, in combination with chitosan and magnetic Fe3O4, a new type of magnetic chitosan/sodium alginate gel bead (MCSB) was prepared. Adsorptive removal of Cu(II) from aqueous solutions was studied by using the MCSB as a promising candidate in environmental application. Different kinetics and isotherm models were employed to investigate the adsorption process. Based on Fourier transform infrared spectroscopy, field-emission scanning electron microscope, CHNS/O elements analysis, vibration magnetometer, and various means of characterization, a comprehensive analysis of the adsorption mechanism was conducted. The MCSB had a good magnetic performance with a saturation magnetization of 12.5 emu/g. Elemental analysis proved that the addition of chitosan introduced a considerable amount of nitrogen-rich groups, contributing significantly to copper adsorption onto gel beads. The contact time necessary for adsorption was optimized at 120 min to achieve equilibrium. Experimental data showed that the adsorption process agreed well with the Langmuir isotherm model and the pseudo-second-order kinetics model. The theoretical maximum adsorption capacity of MCSB for Cu(II) could reach as high as 124.53 mg/g. In conclusion, the MCSB in this study is a novel and promising composite adsorbent, which can be applied for practical applications in due course.

At the Pearl River Estuary of southern China, mercury and its environmental problems have long been a great concern. This study investigated the distribution and speciation of mercury compounds that are significantly influenced by the increasing content of humic acid (HA, a model natural organic matter) in this region. The inorganic mercury and methyl mercury, being adsorbed and converted at different HA levels, were studied in sediments and surface water at both mariculture and their reference sites. In mariculture sediments with higher HA content (up to 4.5%), more mercury were adsorbed at different compound levels, promoting the methylation and accumulation of mercury (P 0.05) at the sediment-water interface. Seasonal shift in environmental temperature might control the HA content, subsequently favouring mercury methylation (maximum 1.75 ± 0.08 mg L

Sewage sludge and bagasse were used as raw materials to produce cheap and efficient adsorbent with great adsorption capacity of Pb(2+). By pyrolysis at 800 °C for 0.5 h, the largest surface area (806.57 m(2)/g) of the adsorbent was obtained, enriched with organic functional groups. The optimal conditions for production of the adsorbent and adsorption of Pb(2+) were investigated. The results of adsorb-ability fitted the Langmuir isotherm and pseudo-second-order model well. The highest Pb(2+) (at pH = 4.0) adsorption capacity was achieved by treating with 60% (v/v) HNO3. This is a promising approach for metal removal from wastewater, as well as recycling sewage sludge and bagasse to ease their disposal pressure.

BACKGROUND The use of cell-surface display technology to express recombinant proteins on a microbial cell surface can enhance metal adsorption to microbial cells. The transcription factor CadR of Pseudomonas putida shows highly selective affinity with Cd2+. RESULTS CadR was genetically engineered by truncating 47 N-terminal amino acids and 21 C-terminal amino acids in order to maximize its expression efficiency while maintaining its metal-binding domain. The redesigned CadR (named T68CadR) was then displayed with Saccharomyces cerevisiae a-agglutinin cell-surface display system. This engineering approach enhanced the H+/OH− buffering capacity and the Cd2+ adsorption capacity of yeast cells. The surface-engineered cells also performed well at mesophilic and higher temperatures (30–50 °C) under neutral or alkalescent conditions. With an initial concentration of 1.0 mg L−1, the Cd2+ removal efficiency remained 85% when the concentration of Na+ changed from 0 to 400 mmol L−1 (pH 7.8). The surface-engineered cells also showed highly selective adsorption to Cd2+ in the presence of Zn2+ and Pb2+. CONCLUSIONS T68CadR displayed yeast cells constructed in this study provide an option to selectively remove Cd in water. It also might be promising as a tool to determine CadR's Cd-binding mechanism and to improve its selectivity and affinity to Cd2+. © 2015 Society of Chemical Industry

A novel titanium dioxide (TiO2)–quaternized poly(vinyl alcohol) (QAPVA) hybrid anion exchange membrane (T membrane) is prepared, and its feasibility for use in microbial fuel cells (MFCs) is investigated in this study. Compared with proton membranes, such as Nafion 117 (N membrane) and an anion exchange membrane (AEM) LeHoAM-III (L membrane), the T membrane exhibits much better performance in MFCs. The oxygen mass transfer coefficient (Ko) of the T membrane (0.05 × 10−4 cm s−1) is one order of magnitude less than that of the N membrane (Ko = 0.3 × 10−4 cm s−1), resulting in reduced substrate loss and increased columbic efficiency (CE) for the MFC with the T membrane. The output voltage and power density of a MFC with the T membrane is higher than cells containing the other two membranes. The CE of the MFC with the T membrane is 1.36 times that of the N membrane and 1.4 times that of the L membrane. The maximum power density of the MFCs obtained was 125.4, 65.0 and 35.6 mW m−2 for the T, N and L membranes, respectively. The results of this study indicate that this new membrane has the potential to substitute for the Nafion membrane in MFCs.

C28H30F4N2O8Ni, Monoclinic, P2 1/n, a = 10.164(7) Å, b = 13.927(9) Å, c = 11.409(8) Å, β = 111.863(10) V = 1498.9(18) Å3, Z = 2, R gt (F) = 0.0389, wR ref (F 2 ) = 0.0957, T = 296(2) K.

The aim of this work was to study a hybrid bioreactor landfill technology for landfill methane production from municipal solid waste. Two laboratory-scale columns were operated for about ten months to simulate an anaerobic and a hybrid landfill bioreactor, respectively. Leachate was recirculated into each column but aeration was conducted in the hybrid bioreactor during the first stage. Results showed that leachate pH in the anaerobic bioreactor maintained below 6.5, while in the hybrid bioreactor quickly increased from 5.6 to 7.0 due to the aeration. The temporary aeration resulted in lowering COD and BOD5 in the leachate. The volume of methane collected from the hybrid bioreactor was 400 times greater than that of the anaerobic bioreactor. Also, the methane production rate of the hybrid bioreactor was improved within a short period of time. After about 10 months' operation, the total methane production in the hybrid bioreactor was 212 L (16 L/kgwaste).

Based on environmental and energetic analysis, a novel combined approach using bioelectrochemical systems (BES) followed by electrolysis reactors (ER) was tested for heavy metals removal from fly ash leachate, which contained high detectable levels of Zn, Pb and Cu according to X-ray diffraction analysis. Acetic acid was used as the fly ash leaching agent and tested under various leaching conditions. A favorable condition for the leaching process was identified to be liquid/solid ratio of 14:1 (w/w) and leaching duration 10 h at initial pH 1.0. It was confirmed that the removal of heavy metals from fly ash leachate with the combination of BESs and ER is feasible. The metal removal efficiency was achieved at 98.5%, 95.4% and 98.1% for Cu(II), Zn(II), and Pb(II), respectively. Results of scanning electron microscopy (SEM) and energy-dispersive X-ray spectroscopy (EDS) indicated that Cu(II) was reduced and recovered mainly as metal Cu on cathodes related to power production, while Zn(II) and Pb(II) were not spontaneously reduced in BESs without applied voltage and basically electrolyzed in the electrolysis reactors.

The occurrence and fate of free and conjugated estrogens were investigated in wastewater and sludge from five sewage treatment plants (STPs) in Guangdong Province, China. Estrone (E1) and 17β-estradiol (E2) were found in all influent samples at concentrations of 69.3-280 ng L(-1) and 1.3-30 ng L(-1), respectively. The concentrations of conjugated estrogens were from ND (not detected) to 7.6 ng L(-1). High concentrations (27.6-235 ng g(-1)) of E1 were found in sludge of some STPs indicating that sorption was an important estrogen removal mechanism. According to the mass flux analyses for estrogens in STP-A, E2 was mainly removed in the anaerobic process and E1 removal was the combined efforts of biodegradation and sorption. Abnormally high concentrations of EE2 (42.6-246 ng L(-1)), detected with gas chromatography-mass spectrometry, were found in all influent samples of the STPs, therefore interlaboratory analysis with liquid chromatography-tandem mass spectrometry was conducted for confirmation, which detected no EE2 at all. In consideration of the rather lower estimated EE2 concentration than the measured value, it was speculated that the presence of interfering substances like tetracosanic acid in the matrix could lead to overestimation of EE2 concentration. Overall, the effluents still pose potential estrogenic effect to the downstream aquatic organisms.

C16H18N4O8, monoclinic, C2/m (no. 12), a = 14.517(4) Å, b = 18.006(7) Å, c = 6.916(3) Å, β = 116.97(3)°, V = 1611.2(11) Å3, Z = 4, R gt(F) = 0.0497, wR ref(F 2) = 0.1387, T = 296(2) K.

A Pseudomonas putida whole-cell bioreporter for detecting bioavailable copper was constructed by inserting a CueR-regulated sensor element upstream of a promoterless green fluorescent protein (GFP) reporter gene. The constructed bioreporter cells expressed GFP only in response to Cu and Ag when cultivated in different metal salt solutions. M9 supplemented medium provided higher sensitivity compared with LB medium. The optimal test condition was cell suspension with an OD600 of 0.4-0.5 incubated at 30 °C. The detection range of Cu is 1-70 mg/l under optimal test condition in M9 supplemented medium.

Heavy metal contamination has become a worldwide environmental concern due to its toxicity, non-degradability and food-chain bioaccumulation. Conventional physical and chemical treatment methods for heavy metal removal have disadvantages such as cost-intensiveness, incomplete removal, secondary pollution and the lack of metal specificity. Microbial biomass-based biosorption is one of the approaches gaining increasing attention because it is effective, cheap, and environmental friendly and can work well at low concentrations. To enhance the adsorption properties of microbial cells to heavy metal ions, the cell surface display of various metal-binding proteins/peptides have been performed using a cell surface engineering approach. The surface engineering of Gram-negative bacteria, Gram-positive bacteria and yeast towards the adsorption of heavy metals are reviewed in this article. The problems and future perspectives of this technology are discussed.

This study confirmed the feasibility of natural limonite working as the iron catalyst for the PNP wastewater treatment in the BES-Fenton system. After the start-up period of the BES-Fenton systems, air and limonite powder were injected into the cathode chamber as the original materials for manufacturing Fenton reagents of H2O2 and Fe(II) respectively. The experiment parameters like pH, external resistance, limonite dosage and initial PNP concentration were investigated in this research. The removal efficiency of PNP (0.25 mM) could achieve 96% in 6 h under the optimal experimental conditions. A limonite dosage of 112 mg per 50 ml of PNP solution at 0.25 mM concentration each time could sustain 7 cycles of the BES-Fenton system operation with PNP removal efficiency >94%. This study suggests an efficiency and cost-effective approach for the PNP removal by using the natural limonite as the iron catalyst of the BES-Fenton system.

The metalloprotein, CadR, was redesigned to optimize cadmium and mercury specificity of CadR-based E. coli biosensors. By truncating 10 and 21 amino acids from the C-terminal extension of CadR, CadR-TC10 and CadR-TC21 were obtained, respectively. The genes cadR, cadR-TC10 and cadR-TC21 were used as sensing elements to construct green fluorescent protein based E.coli biosensors. Induction at 30 °C for 4 h in supplemented M9 medium was the optimized condition for the biosensor. Compared with CadR-based biosensor, there was a clear decline in induction coefficient for CadR-TC21-based biosensor (decreased by 86 % in Zn(II), 44 % in Hg(II), and only 37 % in Cd(II)). While in CadR-TC10-based biosensor, the induction coefficient decreased by 95 % in Zn(II), 70 % in Hg(II), and 67 % in Cd(II). Improved performances of CadR mutants based E. coli biosensors indicated that truncating C-terminal extension of CadR could improve the specificity.

Three types of CueR proteins were anchored on the surface of Saccharomyces cerevisiae cells via surface display technology. The surface-engineered cells showed enhanced adsorption capacity and specificity toward Ag (I) in aqueous phase than control groups. A series of experiments were conducted to investigate the resistance of the surface-engineered cells toward environmental changes including pH, temperature, and eluent. The surface-engineered Saccharomyces cerevisiae cells had the highest adsorption capacity of 2.799 mg/g, which was 87.3% higher than original cells. The engineered cells were able to tolerate an acidic environment (pH=3.0 to 5.0) and high temperature (up to 50°C) with relatively stable adsorption performance. Desorption efficiency was 11% (pH=5.0, 1 mM eluent), which implied the absorbed Ag (I) ions bonded to the cells with high affinity.

In the present study, the Hg contamination in mariculture sites located at the estuary of Pearl River was to investigate with an attempt to analyse associated health risks of dietary exposure to both total mercury (THg) and methyl mercury (MeHg) in cultured fish and shellfish. The highest total mercury concentration (7.037 ± 0.556 ng L-1) of seawater was observed at Zhuhai Estuary. The Hg concentrations of sediment in Guishan Island were significantly higher (p

C26H28N8Br2O12Zn, monoclinic, P21/n (no. 14), a =7.8948(10) Å, b = 17.404(2) Å, c = 11.9437(15) Å, β = 98.719(2)°, V = 1622.1(4) Å3, Z = 2, R gt(F) = 0.0269, wR ref(F 2) = 0.0680, T = 296(2) K.

In order to comprehend the terrestrialization situation and its driving factors in Lake Nansi,the whole Lake Nansi and 21 inlets of the rivers entering the lake were sampled and investigated in August 2008,June 2009,August 2009,June 2010 and August 2010.The results showed that only 4 sites located in the Natural Reserve of Weishan Island and the inlet of Jiehe River with dense shipping belonged to no terrestrialization,2 sites lying the inlet of Laowanfu River with busy transport and the open water region of Nanyang Lake to slight terrestrialization,other 6 sites were moderate terrestrialization,12 sites severe terrestrialization and 1 site heavy severe terrestrialization among the 25 sampling sites.The degree of terrestrialization was significantly positively correlated to vegetation types,depth and organic matter content of silt,negatively correlated to pH and dissolved oxygen;the abundance of vegetation was close negatively correlated to depth of water,pH and dissolved oxygen;the silting level was positively to total nitrogen,total phosphorus,organic matter of sediment,negatively to chemical oxygen demand.So apparently the import of exogenous contamination and increase of trophic level promoted the terrestrialization speed,and the unreasonable development in the whole drainage area further accelerated this progress.

The effects on the total nitrogen(TN) and total phosphorus(TP) retention of the inflows and outflows in Wan'an Reservoir,Jiangxi Province were investigated from 2007 to 2009.The results indicated that 1.57 104,2.38 104 and 2.95 104 tons of dissolved nitrogen were trapped in Wan'an Reservoir in 2007,2008 and 2009 respectively,and 7.44 102 t,3.65 103 t of TP in 2007 and 2009,respectively.The retention of TP in Wan'an Reservoir appeared negative in 2008,which reflected exogenous input.The retention efficiencies of dissolved nitrogen were the annual average of 32% with the range of 12%-45%,and retention efficiencies of TP were in the range of-89% to 80%.It suggested that the retention efficiency of nitrogen was lower than that of phosphorus except for 2008.The river runoff was the main factor of the seasonal changes of TN fluxes,and the nutrient concentration was the restriction factor on the retention of TP.

Based on the systematic measurment of nitrogen (N) and phosphorus (P) concentrations in lake water, the main river water, partial agricultural drainage, groundwater and urban sewage, we analyzed the present situations of N and P pollution at the Lake Poyang Basin, and discussed the sources of the pollution primarily. Lake Poyang Basin was polluted by N and P at some extent, while especially Rao River was polluted by N seriously and Xin River was polluted by P badly. The concentrations of total nitrogen and total phosphorus were 1.06±0.28mg/L and 0.067±0.042mg/L respectively in the Lake Poyang water and the lake has subjected to eutrophication status.

High pressure method was used for the first time to produce rectorite clay (REC)/phenolic resin (PF) and organic rectorite clay (OREC)/phenolic resin and montmorillonite (MMT)/phenolic resin (PF) nanocomposites. The structure of the material phase was studied by X-ray diffraction (XRD), transmission electron microscopy (TEM), Fourier transform infrared (FT-IR) spectroscopy, thermogravimetric analysis (TGA), and atomic force microscopy (AFM). The experimental results show that intercalated clay/resin nanocomposites could form under normal temperature and high pressure conditions by the intercalation of polymeric molecules rather than interlayer polymerization.

Without organic solvent or catalyst, polyaspartic acid (PASP) was synthesized from maleic anhydride (MA) and ammonia (AN) under microwave irradiation. The influences of the molar ratio of maleic anhydride to ammonia and the microwave output power and irradiation time on product yield were investigated. Also, the function of microwave in the process was simply addressed. The results showed that when the molar ratio of MA/AN was 1.2, the output power was 900 W, the irradiation time was 3.5 min, and the product yield was highest and its inhibition performance on calcium carbonate was as good as the polymer synthesized by conventional pyrocondensation polymerization. The main function of microwave was its heat effect. Characterization of the product was carried out by IR, 1HNMR, and 13CNMR spectra and the results showed that the product was PASP. The microwave-assisted synthesis process of PASP has many advantages, including quicker reaction rate, high purity, lower cost, and little pollution. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 103:358–364, 2007

TM/TiO2/SiO2 photocatalysts were prepared by the photodeposition method using transition metal salts (TM = Fe3+, Co2+, Ni2+ and Cu2+) as precursors and the surface bond-conjugated TiO2/SiO2 as supporter in N-2 atmosphere, and were characterized by XRD, XPS, UV-Vis diffuse reflection and zeta-potential. Their photocatalytic activities were evaluated using reactive brilliant red K-2G (K-2G) and cationic blue X-GRL (CBX) showing different adsorption behavior on the oxides. Fe, Cu supported TiO2/SiO2 can efficiently extend the light absorption to the visible region. XPS analysis verified that the introduction of transition metal lead to the changes of the electronic environmental of Ti cations and the zeta-potential of oxides. As a result, K-2G has higher adsorption on the modified TiO2/SiO2 than that on the baked one, while the adsorption of CBX has a little change on the both oxides. At the same time, for the photodegradation of K-2G, Fe3+, Co2+, Ni2+-modified catalysts show that their photoactivities are 3.3-2.2 times higher than the bare one. On the contrast, all transition-metal-supported catalysts have no significant activity improvement except that Fe/TiO2/SiO2 shows 1.68 times higher activity for the photodegradation of CBX The results indicate that the photoactivity could be increased in photodegradation of dyes by changing the performances of adsorption to dyes and absorption to light of photocatalyst. (C) 2004 Elsevier B.V. All rights reserved.

Studies of the ultraviolet spectra and ab initio calculations have been carried out for vitamin E, p -benzoquinone and their complex in the present work. Steady-state absorption spectra have been experimentally measured with a Shimadzu UV-2100S spectrometer at room temperature. Measured values of maximum absorptions of vitamin E and p -benzoquinone in methanol are in excellent agreement with those reported in reference. In theoretical calculations, face-to-face conformations of the electron donor–acceptor (EDA) complex have been selected. The geometries of EDA complexes have been determined by searching for the energy minimum through the variation of the center to center distance between the isolated optimized geometries of the donor and the acceptor. The electronically excited states have been investigated by means of complete active space self-consistent field method associated with 6-31G* basis sets. The state optimizations of S 0 and S 1 for EDA complex reveal that the photoexcitation can directly yield an excited charge transfer (CT) state, and the CT absorption arises from the electron transition between two π-type molecular obitals. Based on the approximations of spherical cavity and point dipole, CT absorption in methanol has been investigated by considering the solvent reorganization energy correction.

C14H12O7Cd, orthorhombic, Ima2 (no. 46), a = 30.715(3) Å, b = 7.8833(8) Å, c = 5.8202(6) Å, V = 1409.3(2) Å3, Z = 4, R gt(F) = 0.0159, wR ref(F 2) = 0.0400, T = 296(2) K.

The adsorption and photodegradation have been investigated in illuminated surface bond-conjugated TiO2/SiO2 suspension for five commercial dyes, including cationic dyes, cationic blue X-GRL (CBX) and cationic pink FG (FG), and anionic reactive brilliant red K-2G (K-2G), reactive yellow KD-3G (KD-3G), and acid red B (ARB). Two adsorption modes are proposed. In the TiO2/SiO2 system, CBX and FG (FG) adsorbed on the catalyst surface by a penta-heterocycle N group, whereas, the other three anionic dyes adsorbed on the catalyst surface by a sulfonate group. The mode of adsorption of substrates to the TiO2/SiO2 particle surface is relevant factor to the formation of NH4+. The nitrogen of azo group was transformed to NH4+ ions and N-2 gas, and the penta-heterocycle and benzene-ring- su bsti Lute N groups in CBX and FG were transformed predominantly to NH4+ ions. The triazine ring and its substitute groups are much stable in the period of 8 h irradiation. (C) 2001 Elsevier Science B.V. All rights reserved.

Surface bond-conjugated TiO2/SiO2 was prepared by means of the impregnation method. Based on the results of XRD, FTIR, XPS and BET measurements, the growth of titania (predominantly anatase) on the silica substrate seems to occur by anchoring of the TiO2 phase through Ti-O-Si cross-linking bonds. The structure model of TiO2/SiO2 was proposed. Compared to B-TiO2, the most efficient catalyst is 30 wt.% TiO2/SiO2 (Ims30), which showed three times higher photoactivity for the degradation of reactive 15 (R15). In addition, the catalyst had a higher photoactivity on a silica of smaller particle size than on the silica of larger particles. Silica gel plays the basic role of dispersion and support for power TiO2. The isoelectric point of the catalyst was 3.0 pH units by the measurement of zeta-potential, indicating the presence of the surface acidity of the: catalyst. The photodegradation and the adsorption of R15 and cationic blue X-GRL (CBX) were investigated with the change of initial aqueous pH. (C) 2001 Elsevier Science B.V. All rights reserved.

A new approach that improved the dechlorination and mineralization of 4-chlorophenol (4-CP) was demonstrated in a sequential biocathode-bioanode bioelectrochemical system (BES) with mixed photosynthetic bacteria (PSB). The biocathode with additional PSB inoculation showed higher 4-CP dechlorination efficiency (DE) and maximum current (81.8 ± 2.9%, 0.021 ± 0.002A) than that at abiotic cathode (45.3 ± 3.7%, 0.011 ± 0.002A) (P0.005). Light response in biocathode BES with or without PSB ascertained the important role of PSB played in the dechlorination and current generation. Dechlorination and mineralization of 4-CP was achieved in the sequential biocathode-bioanode BES, which could be further enhanced with PSB inoculation in both cathode chamber and anode chamber. 4-CP DE in the cathode chamber was improved from 55.0 ± 2.0% to 78.8 ± 4.9%, and the phenol degradation in the anode chamber was improved from 65.3 ± 2.1% to 71.3 ± 1.4%. This study directed a new way for improving dechlorination at biocathode and product degradation at bioanode with PSB inoculation in BES.