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1.
Materials (Basel) ; 16(4)2023 Feb 10.
Article in English | MEDLINE | ID: mdl-36837112

ABSTRACT

In this study, Co, Cr, and Ni were selected as the equal-atomic medium entropy alloy (MEA) systems, and Si was added to form CoCrNiSi0.3 MEA. In order to further improve its wear and corrosion properties, CrN film was sputtered on the surface. In addition, to enhance the adhesion between the soft CoCrNiSi0.3 substrate and the super-hard CrN film, a Cr buffer layer was pre-sputtered on the CoCrNiSi0.3 substrate. The experimental results show that the CrN film exhibits a columnar grain structure, and the film growth rate is about 2.022 µm/h. With the increase of sputtering time, the increase in CrN film thickness, and the refinement of columnar grains, the wear and corrosion resistance improves. Among all CoCrNiSi0.3 MEAs without and with CrN films prepared in this study, the CoCrNiSi0.3 MEA with 3 h-sputtered CrN film has the lowest wear rate of 2.249 × 10-5 mm3·m-1·N-1, and the best corrosion resistance of Icorr 19.37 µA·cm-2 and Rp 705.85 Ω·cm2.

2.
Bioelectrochemistry ; 148: 108260, 2022 Dec.
Article in English | MEDLINE | ID: mdl-36096073

ABSTRACT

A diffusive packed anode-bioelectrochemical (Dpa-Bes) system was constructed by feeding waste gas from the cathode to the anode tank in DPa-Bes through a proton exchange membrane (PEM). The high removal of oxygen by the PEM and the effective combination of the two packing materials reduced the electron loss and enhanced the proton transfer capacity, promoting the removal of acetone from the exhaust gas and increasing the output power. The maximum acetone removal efficiency of the modified Dpa-Bes reached ∼99 % after seven days of closed-circuit operation, with a 3.2-fold increase in maximum power density and a 2.27-fold increase in closed-circuit voltage relative to those of the unmodified Dpa-Bes. When the acetone concentration was 2400 ppm, the removal efficiency was 73.22 % and the elimination capacity was at its highest value of 290.21 g/m3/h. Microbial analysis revealed that the conductive filter contained abundant facultative and anaerobic bacteria, whereas the non-conductive filter was rich in aerobic bacteria. The abundance of anaerobic and facultative microorganisms in Dpa-Bes was much higher than in the unmodified Dpa-Bes, and the dominant bacteria were Flavobacterium and Ferruginibacter.


Subject(s)
Bioelectric Energy Sources , Microbiota , Acetone , Alkanesulfonic Acids , Bioelectric Energy Sources/microbiology , Electrodes , Oxygen/chemistry , Protons , Wastewater/chemistry
3.
Chemosphere ; 288(Pt 3): 132619, 2022 Feb.
Article in English | MEDLINE | ID: mdl-34678352

ABSTRACT

Untreated wastewater containing fluoroquinolone antibiotics poses serious hazards to aquatic species and human health; therefore, treatment of waste expanded polystyrene (EPS) is a crucial environmental matter. In this study, waste EPS was modified with a H2SO4/biodegradable chelating agent, [S,S]-ethylenediamine-N,N'-disuccinic acid (EDDS), and used for highly efficient adsorption of the fluoroquinolone antibiotic ciprofloxacin. When ciprofloxacin of 25 mg/L was used, the H2SO4-modified EPS (EPSH2SO4) adsorbed 60.5% of the ciprofloxacin. During sulfonation, adding a low dose of EDDS markedly improved the adsorption ability of EPSH2SO4+EDDS. The optimal modification conditions were 95% H2SO4, 0.002 M EDDS, 80 °C, and 40 min. The increased adsorbent doses enhanced the adsorption. Approximately 0.2 g/L of EPSH2SO4+EDDS could effectively adsorb 97.8% of the ciprofloxacin (554.3 mg/g) within 30 min. Solution pH0 greatly influenced the adsorption, and the most suitable pH0 was 6. The Langmuir isotherm accurately described the adsorption behaviors of both EPSH2SO4 and EPSH2SO4+EDDS (R2 = 0.997-0.998). The adsorption ability of EPSH2SO4+EDDS (qmax = 1250 mg/g) was 32 times higher than that of EPSH2SO4 (qmax = 38.6 mg/g). A total of 1 M HCl effectively regenerated the exhausted adsorbent. The optimal solid/liquid ratio and time were 0.08 g/20 mL and 60 min, respectively. The regenerated EPSH2SO4+EDDS maintained a high adsorption ability (87.2%) after 10 regeneration cycles. The results thus indicate that the EPSH2SO4+EDDS adsorption-regeneration process is a potential approach to remove ciprofloxacin from water.


Subject(s)
Polystyrenes , Water Pollutants, Chemical , Adsorption , Anti-Bacterial Agents , Chelating Agents , Fluoroquinolones , Humans , Wastewater , Water
4.
Ecotoxicol Environ Saf ; 225: 112759, 2021 Dec 01.
Article in English | MEDLINE | ID: mdl-34500387

ABSTRACT

This study aimed to investigate the transformation of copper oxide nanoparticles (CuO NPs) in aquatic environments under different ionic strength and further examine its effects on copper toxicity and bioaccumulation by monitoring the responses and uptake behaviours of zebrafish embryo. Ionic strength (IS) was simulated according to surface water (1.5 mM), groundwater (15 mM), and wastewater (54 mM), representing low-, mid-, and high-IS water, respectively. At the highest exposure of 10 mg CuO/L, zebrafish larvae mortality was increased from 21.3% to 33.3%, when IS decreased from 54 to 1.5 mM. Low-IS solution also caused the highest numbers of delayed hatching embryo (81.3%) and opaque yolk deformation (36.3%). Copper bioaccumulation markedly increased when larvae were exposed to low-IS water (35%) relative to high-IS water (15%). Exposing to low-IS particularly enhanced copper uptake (~15 ng Cu/g inside embryo), facilitating the copper accumulation in the heart of larvae, whereas aggregated CuO NPs (>500 nm) in mid- and high-IS water were blocked from the embryo and found abundantly in the body axis and tail. Results indicate that CuO NPs in low-IS solutions rapidly form the relatively small CuO NP aggregates with a high copper dissolution, which would pose great concern for aquatic organisms.


Subject(s)
Metal Nanoparticles , Nanoparticles , Water Pollutants, Chemical , Animals , Bioaccumulation , Copper/toxicity , Metal Nanoparticles/toxicity , Osmolar Concentration , Oxides , Water Pollutants, Chemical/analysis , Water Pollutants, Chemical/toxicity , Zebrafish
5.
Chemosphere ; 271: 129529, 2021 May.
Article in English | MEDLINE | ID: mdl-33434822

ABSTRACT

Norfloxacin, a fluoroquinolone antibiotic, is widely used to treat microbial infections. However, untreated norfloxacin-containing wastewater poses serious threats to the ecosystem and human health. The treatment of waste expanded polystyrene (EPS) by landfilling or incineration could cause environmental problems. In this research, the feasibility of converting EPS into a valuable adsorbent for norfloxacin was evaluated. Results showed that EPS treated with H2SO4 (EPSH2SO4) effectively adsorbed norfloxacin. The optimal sulfonation conditions were 95% H2SO4 and 100 °C. Addition of 0.001 M of persulfate during sulfonation obviously shortened the sulfonation time to 7.5 min, and the adsorption ability of modified EPS increased with increasing persulfate dose. Under the experimental conditions of 25 mg L-1 norfloxacin, pH0 6.2, and 0.4 g L-1 EPSH2SO4+persulfate (dry weight), 97.2% of norfloxacin could be removed after 30 min of adsorption. The adsorption ability of EPSH2SO4+persulfate decreased with increasing solution pH0, and the optimal pH0 was 6.2. The Langmuir isotherm best described the adsorption behavior of EPSH2SO4+persulfate (qmax = 140.9 mg L-1, b = 1.97 L mg-1, R2 = 0.9992). 1 M HCl effectively regenerated the exhausted EPSH2SO4+persulfate at the optimal solid/solution ratio of 8 g L-1. EPSH2SO4+persulfate maintained excellent adsorption capacity (>80.9%) after eight adsorption-regeneration cycles.


Subject(s)
Polystyrenes , Water Pollutants, Chemical , Adsorption , Anti-Bacterial Agents , Ecosystem , Fluoroquinolones , Humans , Hydrogen-Ion Concentration , Kinetics , Wastewater , Water Pollutants, Chemical/analysis
6.
Int J Biol Macromol ; 173: 211-218, 2021 Mar 15.
Article in English | MEDLINE | ID: mdl-33482215

ABSTRACT

Fluoroquinolone antibiotics are widely used in human and veterinary medicine. However, untreated fluoroquinolone seriously threatens the ecosystem and human health. In this study, deep eutectic solvents (DESs) were applied for the hydrolysis of waste feathers, and the keratin particles (KPs) in a low-cost teabag were utilized to adsorb fluoroquinolone norfloxacin. Results showed that choline chloride/ethylene glycol DES rapidly hydrolyzed feathers within 10 min, and the undissolved particles effectively adsorbed norfloxacin. Adding KOH markedly shortened the hydrolysis time (6 min) and increased the adsorption ability of KPs. The optimum hydrolysis conditions were DES ratio of 1 g: 4.67 g, KOH of 35.68 g L-1, and temperature of 90 °C. When KPDES+KOH of 2 g L-1, norfloxacin of 25 mg L-1, and pH0 7 were used, 94% of norfloxacin was removed in 60 min. A low-cost teabag effectively separated the KPs from the solution after adsorption and did not decrease the adsorption ability of the KPs. The Langmuir isotherm model well described the adsorption behavior of KPsDES+KOH (qmax = 79.36 mg g-1, R2 = 0.9972). In addition, acetone efficiently regenerated the exhausted KPsDES+KOH. The KPs maintained >80% of its adsorption ability after seven cycles of regeneration.


Subject(s)
Anti-Bacterial Agents/chemistry , Feathers/chemistry , Fluoroquinolones/chemistry , Keratins/chemistry , Solvents/chemistry , Adsorption , Animals , Choline/chemistry , Ethylene Glycol/chemistry , Hydrolysis , Industrial Waste/analysis , Molecular Structure , Norfloxacin/chemistry
7.
Chemosphere ; 263: 127919, 2021 Jan.
Article in English | MEDLINE | ID: mdl-32829221

ABSTRACT

Column systems were used to evaluate the effectiveness of different bioremediation methods (biostimulation (BS) and bioaugmentation (BA)) in treating sulfolane-contaminated groundwater. Batch test results confirmed that Cupriavidus sp. Y9 (Y9) was the most effective strain for BA. The optimal ratio of added native bacteria to Y9 was 10:3. The BA column adapted to a high sulfolane concentration (150 mg L-1) more rapidly and had higher sulfolane removal efficiency (90%) than did the BS column. The change in the biotoxicity of sulfolane-contaminated groundwater upon bioremediation, according to a Microtox test, revealed decreases in the inhibition of the passing of light by the BS column and BS + BA column of 38% and 63%, respectively. These results reveal that combining BS with BA can reduce the biotoxicity of sulfolane. The column tests confirmed the most effective added bacterium in BA, the operating conditions for high-efficiency bioremediation, and possible problems in its future application. The results provide an important reference for the design of methods for the remediation of contaminated sites.


Subject(s)
Biodegradation, Environmental , Groundwater/microbiology , Thiophenes/metabolism , Water Pollutants, Chemical/metabolism , Bacteria/metabolism , Soil Pollutants/analysis
8.
J Environ Manage ; 277: 111487, 2021 Jan 01.
Article in English | MEDLINE | ID: mdl-33049609

ABSTRACT

Groundwater near refinery and natural gas plants often contain elevated concentrations of toxic sulfolane. Studies on any concentration of sulfolane are limited. Column experiment was conducted to investigate the effects of adding a low dose of H2O2 and nutrient on bioremediation. Vibrio fischeri light inhibition test was used evaluate the toxicity of effluents. The continuous column experiment conditions were sulfolane at 100 mg L-1, dissolved oxygen at 7 mg L-1, absence of phosphorus, and very short hydraulic retention time (7.9 h). A low dose of H2O2 (5.88 mM) enhanced the sulfolane (27.1%) and COD removal (11.8%) in comparison with the control set. Adding nutrient increased bicinchoninic acid protein assay levels, sulfolane removal (99.6%) and COD removal (80.3%). Addition of both H2O2 and nutrient further improved COD removal (90.3%) and COD/sulfolane ratio (0.90) and toxicity removal (Vibrio fischeri light inhibition ratio < 1%). Batch experiment indicated the degraders tolerated sulfolane up to 400 mg L-1. The DGGE method and dendrogram analysis were utilized to investigate the changes of degrader community structure.


Subject(s)
Environmental Pollutants , Groundwater , Microbiota , Water Pollutants, Chemical , Biodegradation, Environmental , Hydrogen Peroxide , Water Pollutants, Chemical/analysis , Water Pollutants, Chemical/toxicity
9.
Resuscitation ; 146: 96-102, 2020 01 01.
Article in English | MEDLINE | ID: mdl-31756360

ABSTRACT

BACKGROUND: Dispatcher-assisted cardiopulmonary resuscitation (DACPR) could improve the survival rate of out-of-hospital cardiac arrest (OHCA). However, the efficiency of DACPR varies. Our study compared the effectiveness of DACPR instructed via landline calls, mobile calls, and landline calls transferred to mobiles. METHOD: This prospective cohort study enrolled patients with OHCA between 1 July 2017 and 30 November 2018 in Taichung. Patients were divided into a mobile group and a landline group according to device used to call emergency medical services (EMS). The landline group was subdivided according to whether the call was transferred to a mobile. We compared the DACPR rate and call to chest compression time between groups. RESULTS: The study comprised 2404 cases after exclusion: 934 cases of DACPR via mobile and 1470 via landline. In the mobile group, DACPR rate (54% vs. 47.5%, P <  0.001) was higher and call to chest compression time (median: 156 s vs. 174 s P < 0.001) was shorter than in the landline group. In the transferred group, DACPR rate (72.7% vs. 28.8%, P <  0.001) was higher than in the non-transferred group, but no difference was observed in call to chest compression time (median: 173 s vs. 177 s, P = 0.69). CONCLUSION: According to this city-based prospective clinical study, communication over mobiles resulted in higher DACPR rate and shorter call to chest compression time than that over landlines. Transferring calls from a landline to a mobile could increase the DACPR rate without delaying the initiation of chest compression.


Subject(s)
Cardiopulmonary Resuscitation , Distance Counseling/organization & administration , Emergency Medical Dispatch , Emergency Medical Service Communication Systems/organization & administration , Heart Massage , Aged , Cardiopulmonary Resuscitation/methods , Cardiopulmonary Resuscitation/statistics & numerical data , Cohort Studies , Emergency Medical Dispatch/methods , Emergency Medical Dispatch/statistics & numerical data , Female , Heart Massage/methods , Heart Massage/statistics & numerical data , Humans , Male , Out-of-Hospital Cardiac Arrest/diagnosis , Out-of-Hospital Cardiac Arrest/mortality , Out-of-Hospital Cardiac Arrest/therapy , Outcome and Process Assessment, Health Care , Prospective Studies , Survival Analysis , Taiwan/epidemiology , Telecommunications/instrumentation , Telecommunications/statistics & numerical data , Time-to-Treatment/statistics & numerical data
10.
Chemosphere ; 205: 570-578, 2018 Aug.
Article in English | MEDLINE | ID: mdl-29709808

ABSTRACT

It was hypothesized that interactions between emerging contaminants such as decabromodiphenyl ether (BDE-209) and nanoparticles (NPs) such as nano-SiO2 (nSiO2), can affect contaminant transport in the aquatic environment and its ecotoxicity. This study assessed the influence of nSiO2 on the uptake of BDE-209 by zebrafish embryo. The distribution of BDE-209 and nSiO2 on the external chorion and the internal embryo mass (i.e., dechorionated embryo) was measured. For single exposure of nSiO2 to zebrafish embryo, separately, results showed that nSiO2 accumulation on the chorion surface was higher than that in the dechorionated embryo. The nSiO2 accumulation on the chorion surface was 129-200 mg-nSiO2/g-chorion at 48 h post fertilization, hpf, of exposure time, whereas the equilibrium adsorption of nSiO2 on the dechorionated embryo was ca. 0.42-0.54 mg-nSiO2/g-embryo at 6 hpf. Results showed that the formation of nSiO2-BDE-209 associates promoted both extracellular and intracellular uptake of BDE-209 by zebrafish embryo, thereby increasing the bioconcentration of BDE-209 on the chorion surface and in embryo. The results also revealed that the accumulation of BDE-209 on the chorion was remarkably greater than that on the dechorionated embryo at 48 hpf. The uptake of BDE-209 was 17.2 ±â€¯0.45 mg/g-chorion (or 86 ng-BDE-209/chorionated embryo) and 0.37 ±â€¯0.01 mg/g-embryo (or 18.6 ng-BDE-209/dechorionated embryo), respectively, when co-exposure of zebrafish embryos to BDE-209 and nSiO2. Results from the SEM and EDS analysis revealed that nSiO2 already passed through the chorion and adhered to the embryo surface/mass.


Subject(s)
Halogenated Diphenyl Ethers/pharmacokinetics , Nanoparticles/chemistry , Silicon Dioxide/pharmacology , Zebrafish/embryology , Adsorption , Animals , Chorion/chemistry , Embryo, Nonmammalian/drug effects , Tissue Distribution
11.
Clin Chim Acta ; 475: 157-163, 2017 Dec.
Article in English | MEDLINE | ID: mdl-29074220

ABSTRACT

BACKGROUND: Colorectal cancer (CRC) is one of the most common malignancies worldwide, and early diagnosis is vital to improving prognoses. We explored the diagnostic potential of a multiplex autoantibody panel as a biomarker for the detection of CRC by ELISA. METHODS: In total, 192 serum samples (92 CRC and 100 matched controls) were tested against a panel of 12 tumor-associated antigens (TAAs): RPH3AL, RPL36, SLP2, p53, survivin, ANAXA4, SEC61B, CCCAP, NYCO16, NMDAR, PLSCR1, and HDAC5. Individual and combined autoantibody signatures were examined. RESULTS: Compared to individual autoantibody markers, the combinations of TAAs provided better discrimination between tumorous and normal sera. The overall sensitivity of a selected panel of four antibodies (anti-SLP2, -p53, -SEC61B, and -PLSCR1) was 64.1%, with a specificity of 80% that increased to 83.7% when carcinoembryonic antigen (CEA) measurement was added. Furthermore, the sensitivity of the panel of four antibodies for early and advanced stages of CRC was 66.7% and 62%, increasing to 88.3% and 84%, respectively, when CEA was added. CONCLUSIONS: We identified a panel of four antibodies as a promising diagnostic biomarker for the detection of CRC.


Subject(s)
Antigens, Neoplasm/genetics , Autoantibodies/blood , Biomarkers, Tumor/blood , Colorectal Neoplasms/diagnosis , Immunoassay , Adult , Aged , Aged, 80 and over , Antigens, Neoplasm/immunology , Blood Proteins/genetics , Blood Proteins/immunology , Carcinoembryonic Antigen/genetics , Carcinoembryonic Antigen/immunology , Case-Control Studies , Colorectal Neoplasms/blood , Colorectal Neoplasms/genetics , Colorectal Neoplasms/immunology , Early Detection of Cancer/methods , Female , Humans , Male , Membrane Proteins/genetics , Membrane Proteins/immunology , Middle Aged , Neoplasm Staging , Phospholipid Transfer Proteins/genetics , Phospholipid Transfer Proteins/immunology , Prognosis , SEC Translocation Channels/genetics , SEC Translocation Channels/immunology , Sensitivity and Specificity , Tumor Suppressor Protein p53/genetics , Tumor Suppressor Protein p53/immunology
12.
J Environ Manage ; 204(Pt 1): 12-16, 2017 Dec 15.
Article in English | MEDLINE | ID: mdl-28846890

ABSTRACT

Both a low concentration of dissolved oxygen and the toxicity of a high concentration of BTEX inhibit the bioremediation of BTEX in groundwater. A novel method of preparing encapsulated oxygen-releasing beads (encap-ORBs) for the biodegradation of BTEX in groundwater was developed. Experimental results show that the integrality and oxygen-releasing capacity of encap-ORBs exceeded those of ORBs. The use of polyvinyl alcohol (PVA) with high M.W. to prepare encap-ORBs improved their integrality. The encap-ORBs effectively released oxygen for 128 days. High concentration of BTEX (480 mg L-1) inhibited the biodegradation by the free cells. Immobilization of degraders in the encap-ORB alleviated the inhibition. Scanning electron microscope analysis reveals that the BTEX degraders grew on the surface of encap-ORB after bioremediation. The above results indicate that the encap-ORBs were effective in the bioremediation of BTEX at high concentration in groundwater.


Subject(s)
Benzene Derivatives/chemistry , Oxygen/chemistry , Polyvinyl Alcohol/chemistry , Toluene/chemistry , Water Pollutants, Chemical/metabolism , Xylenes/chemistry , Biodegradation, Environmental , Groundwater , Oxygen/metabolism
13.
J Environ Manage ; 193: 551-557, 2017 May 15.
Article in English | MEDLINE | ID: mdl-28245943

ABSTRACT

A low-cost mini tubular microbial fuel cell (MFC) was developed for treating groundwater that contained benzene in monitoring wells. Experimental results indicate that increasing the length and density, and reducing the size of the char particles in the anode effectively reduced the internal resistance. Additionally, a thinner polyvinyl alcohol (PVA) hydrogel separator and PVA with a higher molecular weight improved electricity generation. The optimal parameters for the MFC were an anode density of 1.22 g cm-3, a coke of 150 µm, an anode length of 6 cm, a PVA of 105,600 g mol-1, and a separator thickness of 1 cm. Results of continuous-flow experiments reveal that the increasing the sets of MFCs and connecting them in parallel markedly improved the degradation of benzene. More than 95% of benzene was removed and electricity of 38 mW m-2 was generated. The MFC ran continuously up to 120 days without maintenance.


Subject(s)
Benzene , Bioelectric Energy Sources , Electricity , Electrodes , Groundwater
14.
Int J Phytoremediation ; 17(1-6): 429-36, 2015.
Article in English | MEDLINE | ID: mdl-25495933

ABSTRACT

Reductants are often used to reduce Cr(VI) in chemical treatments, yet the effects of the reductants on Cr(VI) phytoremediation are not fully understood. This study investigates the effects of different reductants on Cr(VI) phytoremediation by Ipomoea aquatica in simulated solution with 3 mg L(-1) of Cr(VI), pH0 of 6, and an incubation time of 5 days. Results indicate that the applications of S2O3(2-), Fe0, and Fe2+ at low doses notably increased root Cr concentrations, which were obviously higher than that those in the control (Cr6+ alone). However, high reductant concentrations decreased bioaccumulation of Cr in the roots and shoots of the plant. Statistical results indicate that Cr concentrations were significantly and negatively correlated with Fe concentrations in the roots and shoots of the plant (p<0.05). This suggest that Fe accumulation inhibited Cr accumulation in the plant. A Cr(VI) concentration of 3 mg L(-1) caused short, brown lateral roots with tip necrosis, leaf chlorosis, and noticeable shoot wilting. The leaf necrosis and shoot wilting is caused by oxidative damage of lateral roots by Cr(VI) rather than by the reactive oxygen species generated by the oxidative stress. Addition of the reductants effectively reduced these plant injuries.


Subject(s)
Chromium/metabolism , Environmental Restoration and Remediation/methods , Ipomoea/metabolism , Oxidants/chemistry , Soil Pollutants/metabolism , Biodegradation, Environmental , Chromium/chemistry , Environmental Restoration and Remediation/instrumentation , Ipomoea/chemistry , Oxidation-Reduction , Plant Leaves/chemistry , Plant Leaves/metabolism , Plant Roots/chemistry , Plant Roots/metabolism , Soil Pollutants/chemistry
15.
Bioprocess Biosyst Eng ; 37(6): 1085-93, 2014 Jun.
Article in English | MEDLINE | ID: mdl-24170019

ABSTRACT

Alleviation of metal inhibition on BTEX degradation using PVA-immobilized degrader (Mycobacterium sp. CHXY119) was investigated. When BTEX of 29 mg L(-1) [B:T:E:X = 1:1:1:1 (mg)] was used, more than 99 % of BTEX was simultaneously degraded by the free cells within 170 h. In contrast, BTEX of 114-172 mg L(-1) seriously inhibited degradation. High concentrations of metals (Mn(2+): 15, Ni(2+): 10, and Zn(2+): 10 mg L(-1)) also strongly inhibited BTEX degradation by the free cells at BTEX of 29 mg L(-1). Immobilization of degraders alleviated the inhibition of BTEX and heavy metals at high concentrations. A modified non-competitive inhibition model well described the BTEX degradation by the free and immobilized cells in the absence and presence of metal ions (R (2) = 0.92-0.99). The above results provide valuable information on treatment of metal-BTEX co-contaminated wastewater by the immobilized degrader.


Subject(s)
Metals/metabolism , Mycobacterium/metabolism , Petroleum Pollution , Polyvinyl Alcohol/chemistry , Water Pollution, Chemical , Water Purification , Biodegradation, Environmental , Cells, Immobilized/metabolism , Metals/chemistry
16.
Bioresour Technol ; 124: 45-51, 2012 Nov.
Article in English | MEDLINE | ID: mdl-23000718

ABSTRACT

Novel oxygen-releasing bead (ORB) and oxygen-releasing immobilized cell bead (ORICB) were prepared. Their oxygen releasing characteristics and effect on degradation of benzene, toluene, ethylbenzene, and xylene (BTEX)-contaminated groundwater were evaluated in a column. ORB prepared by CaO(2)-encapsulated freezing had much better oxygen-releasing capacity (0.526 mg O(2) per ORB) than that by the mixing-freezing method. The encapsulated-ORB did not influence groundwater pH. Two BTEX degraders were utilized to prepare the ORICB. The ORICBs-column rapidly (hydraulic retention time: 0.872 day) degraded BTEX after a 2-5 day acclimation period. The BTEX removal increased as flow distances increased. At BTEX concentration of 120 mg L(-1), 67% of benzene and 81-90% of TEX were removed. The SEM shows that micropores existed in the ORBs and BTEX degraders were immobilized. The denaturing gradient gel electrophoresis profiles indicate that BTEX degraders were distributed throughout the column. The BTEX concentration of 120 mg L(-1) markedly altered the structure of the indigenous microbial community.


Subject(s)
Environmental Restoration and Remediation/methods , Hydrocarbons, Aromatic/metabolism , Oxygen/chemistry , Water Pollutants, Chemical/metabolism , Base Sequence , DNA Primers , Electrophoresis, Polyacrylamide Gel , Groundwater/chemistry , Microscopy, Electron, Scanning
17.
Environ Pollut ; 168: 54-61, 2012 Sep.
Article in English | MEDLINE | ID: mdl-22591789

ABSTRACT

Three common disinfectants were selected in this study to investigate their toxicity to Daphnia magna. The methods used in this study included the traditional acute toxicity test, new embryo toxicity test, and teratogenic test. The study concluded that the acute toxicity of the three disinfectants to young daphnids and embryos were hypochlorite > formaldehyde > m-cresol. The effects on growth mostly occurred in the late stages of organogenesis. Of the organs, the Malpighian tube was the most sensitive to disinfectants during embryonic organogenesis. After exposure of the disinfectants to sunlight for 4 h, acute toxicity and teratogenic effects of hypochlorite on young daphnids decreased by 30% and 71%, respectively, while those of formaldehyde decreased by 35% and 49%, respectively. In addition, comparing toxic endpoints of the three disinfectants with and without sunlight exposure, the embryo tests were equally sensitive to the three-week reproduction test in this study.


Subject(s)
Disinfectants/toxicity , Teratogens/toxicity , Water Pollutants, Chemical/toxicity , Animals , Cresols/toxicity , Daphnia/embryology , Embryo, Nonmammalian/drug effects , Formaldehyde/toxicity , Hypochlorous Acid/toxicity , Malpighian Tubules/drug effects , Toxicity Tests, Acute
18.
J Agric Food Chem ; 60(19): 4914-22, 2012 May 16.
Article in English | MEDLINE | ID: mdl-22524620

ABSTRACT

FIP-fve is a protein that is isolated from Flammulina velutipes . Its known immunomodulatory activities are elicitation of the production of type II interferon from human peripheral mononuclear cells (hPBMCs) and hemagglutination. How the target receptors mediate activation of FIP-fve-induced immunomodulatory effects remains to be elucidated. This study postulates the three-dimensional structures to determine whether the carbohydrate binding module family 34 (CBM-34) on FIP-fve is conserved to site N of Thermoactinomyces vulgaris R-47 α-amylase I. Experimental site-directed mutagenesis data as well as ligand-specific binding competition assay are adopted to identify the key residues W24, T28, D34, T90, I91, and W111 of FIP-fve that participate in binding to polysaccharides that are linked to the membrane of immune cells. Treatments of hPBMCs with tunicamycin and deglycosylation enzymes that removed the carbohydrate moieties reduced the secretion of IFN-γ induction from hPBMCs. In conclusion, the experiments herein demonstrated the ligand-binding CBM-34 on FIP-fve and ligand-like glycoproteins on the surface of hPBMCs must be required to induce physiological immunomodulatory effects.


Subject(s)
Flammulina/chemistry , Fungal Proteins/immunology , Immunologic Factors/immunology , Interferon-gamma/immunology , Leukocytes, Mononuclear/immunology , Receptors, Immunologic/immunology , Amino Acid Motifs , Amino Acid Sequence , Cell Line , Flammulina/genetics , Flammulina/immunology , Fungal Proteins/chemistry , Fungal Proteins/genetics , Fungal Proteins/pharmacology , Humans , Immunologic Factors/chemistry , Immunologic Factors/genetics , Immunologic Factors/pharmacology , Leukocytes, Mononuclear/chemistry , Leukocytes, Mononuclear/drug effects , Molecular Sequence Data , Receptors, Immunologic/chemistry , Receptors, Immunologic/genetics , Sequence Alignment
19.
Environ Technol ; 33(1-3): 17-25, 2012.
Article in English | MEDLINE | ID: mdl-22519084

ABSTRACT

This study evaluates Cu emissions in air-particulate and gas phases during thermal treatment of simulated copper sludge by a rotary kiln. Influences of operating parameters, including treatment temperature (400-700 degrees C), rotary speed (0.89-2.00 rpm) and copper content in sludge (1% to 5% by weight) on copper emissions were investigated. The toxicity characteristic leaching procedure (TCLP) and scanning electron microscopy (SEM) were also conducted to evaluate copper leaching and the surface structure of thermally treated sludge, respectively. The results indicated that (1) low Cu emissions in air-particulate and gas phases were associated with the two operating conditions of 400-500 degrees C at 0.89-1.39 rpm and 600-700 degrees C at 2.00 rpm; (2) temperatures and rotary speeds did not affect gaseous copper emission, except for the operating condition of 400 degrees C at 2.00 rpm; (3) rising copper content of sludge at 600 degrees C and 2.00 rpm increased the particulate copper emission, but not the gaseous copper emission; (5) the TCLP copper leaching concentrations of sludge treated at 400 degrees C were obviously higher than those treated at 500-700 degrees C; however, all of the thermally treated products agreed with the Taiwan EPA TCLP regulations.


Subject(s)
Copper/analysis , Gases/analysis , Waste Management , Hot Temperature , Microscopy, Electron, Scanning
20.
J Hazard Mater ; 195: 324-31, 2011 Nov 15.
Article in English | MEDLINE | ID: mdl-21903325

ABSTRACT

Effects of UV irradiation on humic acid (HA) removal by Fe(0)/air, ozonation and Fenton oxidation were investigated. The trihalomethane forming potential (THMFP) and toxicity of treated solutions were also evaluated. The experimental conditions were ozone of 21 mg min(-1), H(2)O(2) of 8 × 10(-4)M, Fe(0) of 20 g L(-1), air flow of 5 L min(-1), and UVC of 9 W. Results indicated that Fe(0)/air rapidly removed HA color (>99%) and COD (90%) within 9 min. 51-81% of color and 43-50% of COD were removed by ozonation and Fenton oxidation after 60 min. Both UV enhanced ozone and Fenton oxidation removed HA, but the Fe(0)/air process did not. Spectrum results showed all processes effectively diminished UV-vis spectra, except for ozonation. The THMFP of Fe(0)/air-treated solution (114 µg L(-1)) was much lower than those of Fenton- (226 µg L(-1)) and ozonation-treated solutions (499 µg L(-1)). Fe(0)/air with UV irradiation obviously increased the THMFP of treated solution (502 µg L(-1)). The toxicity results obtained from Vibrio fischeri light inhibition test indicated that the toxicity of Fe(0)/air-treated solution (5%) was much lower than that of ozonation- (33%) and Fenton-treated solutions (31%). Chlorination increased the solution toxicity. The correlation between biotoxicity and chloroform in the chlorinated solution was insignificant.


Subject(s)
Air , Aliivibrio fischeri/drug effects , Humic Substances , Iron/chemistry , Ozone/chemistry , Trihalomethanes/chemical synthesis , Ultraviolet Rays , Trihalomethanes/toxicity
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