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1.  Hepatoprotective and antioxidant effects of dietary Glycyrrhiza polysaccharide against TCDD-induced hepatic injury and RT-PCR quantification of AHR2, ARNT2, CYP1A mRNA in Jian Carp (Cyprinus carpio var. Jian)  
   Jinliang Du  Liping Cao  Rui Ji  Guojun Yin《环境科学学报(英文版)》,2017年第29卷第1期
   To evaluate the protective effects of Glycyrrhiza polysaccharide (GPS) against 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD)-induced hepatotoxicity in Jian carp, the fish were fed diets containing GPS at doses of 0.1, 0.5 and 1.0 g/kg for 60 days before an intraperitoneal injection of 0.6 μg/kg TCDD at a volume of 0.05 mL/10 g body weight. At 72 hr post-injection, blood and liver samples were taken for biochemical analysis and the fish liver samples were used for the preparation of pathological slices. The results showed that increases in alanine aminotransferase (GPT), aspartate aminotransferase (GOT), lactate dehydrogenase (LDH), and alkaline phosphatase (AKP) in serum induced by TCDD were significantly inhibited by pre-treatment with 1.0 g/kg GPS. Following the 1.0 g/kg GPS pre-treatment, total protein (TP), albumin (Alb), catalase (CAT), glutathione peroxidase (GPx), total antioxidant capacity (T-AOC) and superoxide dismutase (SOD) activities in liver tissue increased significantly, malondialdehyde (MDA) formation (P < 0.05 or P < 0.01) was significantly inhibited, and the expression of cytochrome P4501A (CYP1A), aryl hydrocarbon receptor 2 (AHR2) and aryl hydrocarbon receptor nuclear translocator 2 (ARNT2) mRNA (P < 0.05) was significantly enhanced. Histological observations on fish liver were obtained by preparing paraffin tissue sections via HE staining, and the results showed that histological changes were obviously reduced by 0.5 and 1.0 g/kg GPS. GPS significantly reduced liver tissue damage caused by TCDD. Overall, these results proved the hepatoprotective effect of GPS in protecting against fish liver injury induced by TCDD, and supported the use of GPS (1.0 g/kg) as a hepatoprotective and antioxidant agent in fish.    

2.  Bioaccumulation and effects of sediment-associated gold- and graphene oxide nanoparticles on Tubifex tubifex  
   Panhong Zhang  Henriette Selck  Stine Rosendal Tanga  Chengfang Pang  Bin Zhao《环境科学学报(英文版)》,2017年第29卷第1期
   With the development of nanotechnology, gold (Au) and graphene oxide (GO) nanoparticles have been widely used in various fields, resulting in an increased release of these particles into the environment. The released nanoparticles may eventually accumulate in sediment, causing possible ecotoxicological effects to benthic invertebrates. However, the impact of Au-NPs and GO-NPs on the cosmopolitan oligochaete, Tubifex tubifex, in sediment exposure is not known. Mortality, behavioral impact (GO-NP and Au-NP) and uptake (only Au-NP) of sediment-associated Au-NPs (4.9 ± 0.14 nm) and GO-NPs (116 ± 0.05 nm) to T. tubifex were assessed in a number of 5-day exposure experiments. The results showed that the applied Au-NP concentrations (10 and 60 μg Au/g dry weight sediment) had no adverse effect on T. tubifex survival, while Au bioaccumulation increased with exposure concentration. In the case of GO-NPs, no mortality of T. tubifex was observed at a concentration range of 20 and 180 μg GO/g dry weight sediment, whereas burrowing activity was significantly reduced at 20 and 180 μg GO/g dry weight sediment. Our results suggest that Au-NPs at 60 μg Au/g or GO-NPs at 20 and 180 μg GO/g were detected by T. tubifex as toxicants during short-term exposures.    

3.  Changes in visibility with PM2.5 composition and relative humidity at a background site in the Pearl River Delta region  被引次数:2
   Xiaoxin Fu  Xinming Wang  Qihou Hu  Guanghui Li  Xiang Ding  Yanli Zhang  Quanfu He  Tengyu Liu  Zhou Zhang  Qingqing Yu  Ruqing Shen  Xinhui Bi《环境科学学报(英文版)》,2016年第28卷第2期
   In fall–winter, 2007–2013, visibility and light scattering coefficients (bsp) were measured along with PM2.5 mass concentrations and chemical compositions at a background site in the Pearl River Delta (PRD) region. The daily average visibility increased significantly (p < 0.01) at a rate of 1.1 km/year, yet its median stabilized at ~ 13 km. No haze days occurred when the 24-hr mean PM2.5 mass concentration was below 75 μg/m3. By multiple linear regression on the chemical budget of particle scattering coefficient (bsp), we obtained site-specific mass scattering efficiency (MSE) values of 6.5 ± 0.2, 2.6 ± 0.3, 2.4 ± 0.7 and 7.3 ± 1.2 m2/g, respectively, for organic matter (OM), ammonium sulfate (AS), ammonium nitrate (AN) and sea salt (SS). The reconstructed light extinction coefficient (bext) based on the Interagency Monitoring of Protected Visual Environments (IMPROVE) algorithm with our site-specific MSE revealed that OM, AS, AN, SS and light-absorbing carbon (LAC) on average contributed 45.9% ± 1.6%, 25.6% ± 1.2%, 12.0% ± 0.7%, 11.2% ± 0.9% and 5.4% ± 0.3% to light extinction, respectively. Averaged bext displayed a significant reduction rate of 14.1/Mm·year (p < 0.05); this rate would be 82% higher if it were not counteracted by increasing relative humidity (RH) and hygroscopic growth factor (f(RH)) at rates of 2.5% and 0.16/year − 1 (p < 0.01), respectively, during the fall–winter, 2007–2013. This growth of RH and f(RH) partly offsets the positive effects of lowered AS in improving visibility, and aggravated the negative effects of increasing AN to impair visibility.    

4.  Growth inhibition and oxidative damage of Microcystis aeruginosa induced by crude extract of Sagittaria trifolia tubers  
   Jiang Li  Yunguo Liu  Pingyang Zhang  Guangming Zeng  Xiaoxi Cai  Shaobo Liu  Yicheng Yin  Xinjiang Hu  Xi Hu  Xiaofei Tan《环境科学学报(英文版)》,2016年第28卷第5期
   Aquatic macrophytes are considered to be promising in controlling harmful cyanobacterial blooms. In this research, an aqueous extract of Sagittaria trifolia tubers was prepared to study its inhibitory effect on Microcystis aeruginosa in the laboratory. Several physiological indices of M. aeruginosa, in response to the environmental stress, were analyzed. Results showed that S. trifolia tuber aqueous extract significantly inhibited the growth of M. aeruginosa in a concentration-dependent way. The highest inhibition rate reached 90% after 6 day treatment. The Chlorophyll-a concentration of M. aeruginosa cells decreased from 343.1 to 314.2 μg/L in the treatment group. The activities of superoxide dismutase and peroxidase and the content of reduced glutathione in M. aeruginosa cells initially increased as a response to the oxidative stress posed by S. trifolia tuber aqueous extract, but then decreased as time prolonged. The lipid peroxidation damage of the cyanobacterial cell membranes was reflected by the malondialdehyde level, which was notably higher in the treatment group compared with the controls. It was concluded that the oxidative damage of M. aeruginosa induced by S. trifolia tuber aqueous extract might be one of the mechanisms for the inhibitory effects.    

5.  The fate of the herbicide propanil in plants of the littoral zone of the Three Gorges Reservoir (TGR), China  
   Zhongli Chen  Andreas Schäffer《环境科学学报(英文版)》,2016年第28卷第10期
   The anti-seasonal hydrology with 30 m water fluctuations in the Three Gorges Reservoir (TGR) of China attracts growing environmental and ecological concerns. We investigated the biotransformation of the herbicide propanil in plants dominating in the littoral zone of the TGR by applying the 14C-ring-labeled herbicide into non-aseptic hydroponic plant systems (Cynodon dactylon, Nelumbo nucifera and Bidens pilosa), aseptic plants (Lemna minor and Lemna gibba) and cell suspension cultures (C. dactylon and L. minor). (1) Propanil absorbed in plants of the hydroponic systems was (12.46 ± 1.63)% of applied radioactivity (AR) (C. dactylon), (52.36 ± 6.38)% (N. nucifera) and (76.55 ± 6.07)% (B. pilosa), respectively. The 14C-residues in the plant extractable fractions and the corresponding media were confirmed by radio-Thin Layer Chromatography (TLC), radio-High Performance Liquid Chromatography (HPLC) and Gas Chromatography-Electron Ionization Mass Spectrometry (GC–EIMS) as propanil, 3,4-dichloroaniline (DCA) and N-(3,4-dichlorophenyl)-β-d-glucopyranosylamine (Glu-DCA). (2) About 8% of AR was taken up by both aseptic plants, from which 7.0% of AR was extracted and identified also as propanil, DCA and Glu-DCA. (3) Concerning cell suspension cultures, (39.22 ± 9.39)% of AR was absorbed by C. dactylon after 72 hr, whereas the accumulated 14C-propanil by L. minor cell suspension culture amounted to (65.04 ± 1.72)% after 7 days. The identified compounds in cell cultures are consistent with those in the tested plants. Most of the pesticide residues in the intact plants were un-extractable, which are recognized as the end of the detoxification process. We therefore consider these plants as suitable for the phytoremediation of the herbicide propanil in the TGR region.    

6.  Temperature dependence of the heterogeneous uptake of acrylic acid on Arizona test dust  
   Qifan Liu  Yidan Wang  Lingyan Wu  Bo Jing  Shengrui Tong  Weigang Wang  Maofa Ge《环境科学学报(英文版)》,2017年第29卷第3期
   In this study, the temperature dependence of the heterogeneous uptake of acrylic acid on Arizona test dust (ATD) has been investigated within a temperature range of 255–315 K using a Knudsen cell reactor. Combined with diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS) experiment, it was found that acrylic acid could adsorb on ATD via surface OH groups and convert to carboxylate on the particle surface. The kinetics study suggests that the initial true uptake coefficient (γt) of acrylic acid on ATD decreases from (4.02 ± 0.12) × 10− 5 to (1.73 ± 0.05) × 10− 5 with a temperature increase from 255 to 315 K. According to the temperature dependence of uptake coefficients, the enthalpy (ΔHobs) and entropy (ΔSobs) of uptake processes were determined to be −(9.60 ± 0.38) KJ/mol and −(121.55 ± 1.33) J·K/mol, respectively. The activation energy for desorption (Edes) was calculated to be (14.57 ± 0.60) KJ/mol. These results indicated that the heterogeneous uptake of acrylic acid on ATD surface was sensitive to temperature. The heterogeneous uptake on ATD could affect the concentration of acrylic acid in the atmosphere, especially at low temperature.    

7.  Ractopamine up take by alfalfa (Medicago sativa) and wheat (Triticum aestivum) from soil  
   Weilin L. Shelver  Thomas M. DeSutter《环境科学学报(英文版)》,2015年第27卷第8期
   Ractopamine is a beta adrenergic agonist used as a growth promoter in swine, cattle and turkeys. To test whether ractopamine has the potential to accumulate in plants grown in contaminated soil, a greenhouse study was conducted with alfalfa (Medicago sativa) and wheat (Triticum aestivum) grown in two soils having different concentrations of organic matter (1.3% and 2.1%), amended with 0, 0.5, and 10 μg/g of ractopamine. Plant growth ranged from 2.7 to 8.8 g dry weight (dw) for alfalfa, and 8.7 to 40 g dw for wheat and was generally greater in the higher organic matter content soil. The uptake of ractopamine in plant tissues ranged from non-detectable to 897 ng/g and was strongly dependent on soil ractopamine concentration across soil and plant tissue. When adjusted to the total fortified quantities, the amount of ractopamine taken up by the plant tissue was low, < 0.01% for either soil.    

8.  Temporal variability of atmospheric particulate matter and chemical composition during a growing season at an agricultural site in northeastern China  被引次数:1
   Weiwei Chen  Daniel Tong  Shichun Zhang  Mo Dan  Xuelei Zhang  Hongmei Zhao《环境科学学报(英文版)》,2015年第38卷第12期
   This study presents the observations of PM10 and PM2.5 concentrations at an agricultural site from April to October 2012 in Dehui city, China. Ambient air was sampled by filter-based samplers and online PM monitors. The filter samples were analyzed to determine the abundance of ionic/inorganic elements, organic carbon (OC) and elemental carbon (EC). The daily PM10 concentrations varied significantly over the monitoring period, with an average of 168 ± 63 (in the range of 52–277) μg/m3 during the land preparation/planting period (26 April–15 June), 85 ± 65 (36–228) μg/m3 during the growing season (16 June–25 September), and 207 ± 88 (103–310) μg/m3 during the harvest period (26 September–31 October). PM2.5 accounted for 44%, 56% and 66% of atmospheric PM10 during these periods, respectively. The PM10 diurnal variation showed a distinct peak from 16:00 to 21:00 (LST) during the growing and harvesting seasons, while a gradual increase throughout the daytime until 17:00 was observed during tilling season. Mineral dust elements (Al, Ca, Fe, and Mg) dominated the PM10 chemical composition during the tilling season; OC, NO3, SO42 − and NH4+ during the growing season; and carbonaceous species (i.e., OC and EC) during the harvesting season. Our results indicate that the soil particles emitted by farm tillage and organic matter released from straw burning are the two most significant sources of PM10 emissions contributing to the recurring high pollution events in this region. Therefore, development of agricultural PM inventories from soil tillage and straw burning is prioritized to support air quality modeling.    

9.  Mitigation of atrazine, S-metolachlor, and diazinon using common emergent aquatic vegetation  
   Matthew T. Moore  Martin A. Locke  Robert Kröger《环境科学学报(英文版)》,2017年第29卷第6期
   By the year 2050, the population of the United States is expected to reach over 418 million, while the global population will reach 9.6 billion. To provide safe food and fiber, agriculture must balance pesticide usage against impacts on natural resources. Challenges arise when storms cause runoff to be transported to aquatic receiving systems. Vegetated systems such as drainage ditches and constructed wetlands have been proposed as management practices to alleviate pesticide runoff. Twelve experimental mesocosms (1.3 × 0.71 × 0.61 m) were filled with sediment and planted with a monoculture of one of three wetland plant species (Typha latifolia, Leersia oryzoides, and Sparganium americanum). Three mesocosms remained unvegetated to serve as controls. All mesocosms were amended with 9.2 ± 0.8 μg/L, 12 ± 0.4 μg/L, and 3.1 ± 0.2 μg/L of atrazine, metolachlor, and diazinon, respectively, over a 4 hr hydraulic retention time to simulate storm runoff. Following the 4 hr amendment, non-amended water was flushed through mesocosms for an additional 4 hr. Outflow water samples were taken hourly from pre-amendment through 8 hr, and again at 12, 24, 48, 72, and 168 hr post-amendment. L. oryzoides and T. latifolia had mean atrazine, metolachlor, and diazinon retentions from 51%–55% for the first 4 hr of the experiment. Aside from S. americanum and atrazine (25% retention), unvegetated controls had the lowest pesticide retention (17%–28%) of all compared mesocosms. While native aquatic vegetation shows promise for mitigation of pesticide runoff, further studies increasing the hydraulic retention time for improved efficiency should be examined.    

10.  Hydrolysis mechanism of carbendazim hydrolase from the strain Microbacterium sp. djl-6F  
   Ji Lei  Shaopeng Wei  Lijun Ren  Shibin Hu  Peng Chen《环境科学学报(英文版)》,2017年第29卷第4期
   The carbendazim (MBC) hydrolyzing enzyme gene was cloned and heterologously expressed in Escherichia coli BL21 (DE3) from a newly isolated MBC-degrading bacterium strain Microbacterium sp. strain djl-6F. High performance liquid chromatography-mass spectrometry (HPLC-MS) analysis revealed that purified MheI-6F protein catalyzes direct hydrolysis of MBC into 2-aminobenzimidazole (2-AB) with a high turnover rate and moderate affinity (Km of 6.69 μmol/L and kcat of 160.88/min) without the need for any cofactors. The optimal catalytic condition of MheI-6F was identified as 45°C, pH 7.0. The enzymatic activity of MheI-6F was found to be diminished by metal ions, and strongly inhibited by sodium dodecyl sulfate (SDS). Through generating amino acid mutations in MheI-6F, Cys16 and Cys222 were identified as the catalytic groups that are essential for the hydrolysis of MBC. This is the first report on the biodegradation of MBC at the enzymatice level.    

11.  Cytogenetic studies of chromium (III) oxide nanoparticles on Allium cepa root tip cells  
   Deepak Kumar  A. Rajeshwari  Pradeep Singh Jadon  Gouri Chaudhuri  Anita Mukherjee  Natarajan Chandrasekaran  Amitava Mukherjee《环境科学学报(英文版)》,2015年第38卷第12期
   The current study evaluates the cytogenetic effects of chromium (III) oxide nanoparticles on the root cells of Allium cepa. The root tip cells of A. cepa were treated with the aqueous dispersions of Cr2O3 nanoparticles (NPs) at five different concentrations (0.01, 0.1, 1, 10, and 100 μg/mL) for 4 hr. The colloidal stability of the nanoparticle suspensions during the exposure period were ascertained by particle size analyses. After 4 hr exposure to Cr2O3 NPs, a significant decrease in mitotic index (MI) from 35.56% (Control) to 35.26% (0.01 μg/mL), 34.64% (0.1 μg/mL), 32.73% (1 μg/mL), 29.6% (10 μg/mL) and 20.92% (100 μg/mL) was noted. The optical, fluorescence and confocal laser scanning microscopic analyses demonstrated specific chromosomal aberrations such as—chromosome stickiness, chromosome breaks, laggard chromosome, clumped chromosome, multipolar phases, nuclear notch, and nuclear bud at different exposure concentrations. The concentration-dependent internalization/bio-uptake of Cr2O3 NPs may have contributed to the enhanced production of anti oxidant enzyme, superoxide dismutase to counteract the oxidative stress, which in turn resulted in observed chromosomal aberrations and cytogenetic effects. These results suggest that A. cepa root tip assay can be successfully applied for evaluating environmental risk of Cr2O3 NPs over a wide range of concentrations.    

12.  Size-resolved aerosol water-soluble ions at a regional background station of Beijing, Tianjin, and Hebei, North China  
   Yongjie Yang  Rui Zhou  Yue Yu  Yan Yan  Yan Liu  Yi'an Di  Dan Wu  Weiqi Zhang《环境科学学报(英文版)》,2017年第29卷第5期
   The characteristics of water-soluble ions in size-resolved particulate matter were investigated using ion chromatography at Shangdianzi, a regional background station of Beijing, Tianjin, and Hebei. Seasonal total concentrations of ions (Na+, Mg2 +, K+, Ca2 +, NH4+, Cl, SO42 − and NO3) were 75.5 ± 52.9 μg/m3 in spring, 26.5 ± 12.3 μg/m3 in summer, 22.7 ± 20.4 μg/m3 in autumn, and 31.1 ± 23.9 μg/m3 in winter, respectively. The secondary ions (NO3, SO42 − and NH4+), mainly associated with fine particles, accounted for 84.2% in spring, 82.1% in summer, 81.5% in autumn and 76.3% in winter of all ions. Strong correlations were found between NH4+ and SO42 − (r = 0.95, p < 0.01) as well as NH4+ and NO3 (r = 0.90, p < 0.01) in fine particles; while in coarse particles, correlations between Mg2 + and NO3 (r = 0.80, p < 0.01), and Ca2 + and NO3 (r = 0.85, p < 0.01) were found. The concentrations of Na+, K+, Mg2 +, Ca2 +, NH4+, Cl, NO3, and SO42 − were 2.02, 0.81, 0.36, 1.65, 9.58, 4.01, 18.9, and 18.4 μg/m3 in particulate matter from southeast-derived air masses, which were typically 1.58–3.37 times higher than in northwest trajectories. Thus, concentrations of water-soluble ions at this background station were heavily influenced by regional transport of serious pollution derived from biomass burning, coal combustion, industrial and vehicle exhaust emissions from Beijing, Tianjin, and Hebei.    

13.  Enhancement of Rhodobacter sphaeroides growth and carotenoid production through biostimulation  
   Shuli Liu  Guangming Zhang  Xiangkun Li  Pan Wu  Jie Zhang《环境科学学报(英文版)》,2015年第27卷第7期
   Bacillus thuringiensis/cereus L2 was added as a biostimulant to enhance the biomass accumulation and carotenoid yield of Rhodobacter sphaeroides using wastewater as the culturing medium. Results showed that biostimulation could significantly enhance the R. sphaeroides biomass production and carotenoid yield. The optimal biostimulant proportion was 40 μL (about 6.4 × 105 CFU). Through the use of biostimulation, chemical oxygen demand removal, R. sphaeroides biomass production, carotenoid concentration, and carotenoid yield were improved by 178%, 67%, 214%, and 70%, respectively. Theoretical analysis revealed that there were two possible reasons for such increases. One was that biostimulation enhanced the R. sphaeroides wastewater treatment efficiency. The other was that biostimulation significantly decreased the peroxidase activity in R. sphaeroides. The results showed that the highest peroxidase activity dropped by 87% and the induction ratio of the RSP_3419 gene was 3.1 with the addition of biostimulant. The enhanced carotenoid yield in R. sphaeroides could thus be explained by a decrease in peroxidase activity.    

14.  Emissions of fluorides from welding processes  
   Ma?gorzata Szewczyńska《环境科学学报(英文版)》,2015年第37卷第11期
   The levels of fluoride airborne particulates emitted from welding processes were investigated. They were sampled with the patented IOM Sampler, developed by J. H. Vincent and D. Mark at the Institute of Occupational Medicine (IOM), personal inhalable sampler for simultaneous collection of the inhalable and respirable size fractions. Ion chromatography with conductometric detection was used for quantitative analysis. The efficiency of fluoride extraction from the cellulose filter of the IOM sampler was examined using the standard sample of urban air particle matter SRM-1648a. The best results for extraction were obtained when water and the anionic surfactant N-Cetyl-N-N-N-trimethylammonium bromide (CTAB) were used in an ultrasonic bath. The limits of detection and quantification for the whole procedure were 8 μg/L and 24 μg/L, respectively. The linear range of calibration was 0.01–10 mg/L, which corresponds to 0.0001–0.1 mg of fluorides per m3 in collection of a 20 L air sample. The concentration of fluorides in the respirable fraction of collected air samples was in the range of 0.20–1.82 mg/m3, while the inhalable fraction contained 0.23–1.96 mg/m3 of fluorides during an eight-hour working day in the welding room.    

15.  Adsorptive removal of antibiotics from water using magnetic ion exchange resin  被引次数:1
   Tianyue Wang  Xun Pan  Weiwei Ben  Jianbing Wang  Pin Hou  Zhimin Qiang《环境科学学报(英文版)》,2017年第29卷第2期
   The occurrence of antibiotics in the environment has recently raised serious concern regarding their potential threat to aquatic ecosystem and human health. In this study, the magnetic ion exchange (MIEX) resin was applied for removing three commonly-used antibiotics, sulfamethoxazole (SMX), tetracycline (TCN) and amoxicillin (AMX) from water. The results of batch experiments show that the maximum adsorption capacities on the MIEX resin for SMX, TCN and AMX were 789.32, 443.18 and 155.15 μg/mL at 25°C, respectively, which were 2–7 times that for the powdered activated carbon. The adsorption kinetics of antibiotics on the MIEX resin could be simulated by the pseudo-second-order model (R2 = 0.99), and the adsorption isotherm data were well described by the Langmuir model (R2 = 0.97). Solution pH exhibited a remarkable impact on the adsorption process and the absorbed concentrations of the tested antibiotics were obtained around the neutral pH. The MIEX resin could be easily regenerated by 2 mol/L NaCl solution and maintained high adsorption removal for the tested antibiotics after regeneration. Anion exchange mechanism mainly controlled the adsorption of antibiotic and the formation of hydrogen binding between the antibiotic and resin can also result in the increase of adsorption capacity. The high adsorption capacity, fast adsorption rate and prominent reusability make the MIEX resin a potential adsorbent in the application for removing antibiotics from water.    

16.  Analysis of trace dicyandiamide in stream water using solid phase extraction and liquid chromatography UV spectrometry  
   Huidong Qiu  Dongdi Sun  Sameera R. Gunatilake  Jinyan She  Todd E. Mlsna《环境科学学报(英文版)》,2015年第35卷第9期
   An improved method for trace level quantification of dicyandiamide in stream water has been developed. This method includes sample pretreatment using solid phase extraction. The extraction procedure (including loading, washing, and eluting) used a flow rate of 1.0 mL/min, and dicyandiamide was eluted with 20 mL of a methanol/acetonitrile mixture (V/V = 2:3), followed by pre-concentration using nitrogen evaporation and analysis with high performance liquid chromatography–ultraviolet spectroscopy (HPLC–UV). Sample extraction was carried out using a Waters Sep-Pak AC-2 Cartridge (with activated carbon). Separation was achieved on a ZIC®-Hydrophilic Interaction Liquid Chromatography (ZIC-HILIC) (50 mm × 2.1 mm, 3.5 μm) chromatography column and quantification was accomplished based on UV absorbance. A reliable linear relationship was obtained for the calibration curve using standard solutions (R2 > 0.999). Recoveries for dicyandiamide ranged from 84.6% to 96.8%, and the relative standard deviations (RSDs, n = 3) were below 6.1% with a detection limit of 5.0 ng/mL for stream water samples.    

17.  Mercury uptake and effects on growth in Jatropha curcas  
   José Marrugo-Negrete  José Durango-Hernández  José Pinedo-Hernández  Germán Enamorado-Montes  Sergi Díez《环境科学学报(英文版)》,2016年第28卷第10期
   The use of metal-accumulating plants for the phytoremediation of contaminated soils is gaining more attention. Mercury (Hg)-contaminated soils from historical gold mines represent a potential risk to human health and the environment. Therefore, Jatropha curcas plant, that has shown its tolerance to these environments, is a species of particular interest to implement phytoremediation techniques in gold mining sites. In this work, the behavior of J. curcas was assessed in different hydroponic cultures fortified with Hg at concentrations of 5, 10, 20, 40, and 80 μg Hg/mL (T5, T10, T20, T40 and T80, respectively). After exposure, plant growth, net photosynthesis, leaf area, and Hg accumulation were determined and variables such as net Hg uptake, effective Hg accumulation, translocation and bioaccumulation factors were calculated. Accumulation of Hg in root and leaf tissues increased with respect to the Hg concentrations in the hydroponic culture, with statistically significant differences (p < 0.05) among treatments. Moreover, Hg concentration in roots was 7 and 12-fold higher in average than in plant leaves and shoots, respectively. Many effects were found in the development of plants, especially related with loss of biomass and leaf area, with significant growth inhibition related to control values (> 50% with treatment T5). Moreover, percentage of inhibition was even higher (> 60%) with same treatment for net photosynthesis. Finally, it should be highlighted that for T40 and T80 treatments, plant growth and photosynthesis were almost completely depleted (88%–95%).    

18.  Large inter annual variation in air quality during the annual festival ‘Diwali’ in an Indian megacity  
   Neha Parkhi  Dilip Chate  Sachin D. Ghude  Sunil Peshin  Anoop Mahajan  Reka Srinivas  Divya Surendran  Kaushar Ali  Siddhartha Singh  Hanumant Trimbake  Gufran Beig《环境科学学报(英文版)》,2016年第28卷第5期
   A network of air quality and weather monitoring stations was established under the System of Air Quality Forecasting and Research (SAFAR) project in Delhi. We report observations of ozone (O3), nitrogen oxides (NOx), carbon monoxide (CO) and particulate matter (PM2.5 and PM10) before, during and after the Diwali in two consecutive years, i.e., November 2010 and October 2011. The Diwali days are characterised by large firework displays throughout India. The observations show that the background concentrations of particulate matter are between 5 and 10 times the permissible limits in Europe and the United States. During the Diwali-2010, the highest observed PM10 and PM2.5 mass concentration is as high as 2070 µg/m3 and 1620 μg/m3, respectively (24 hr mean), which was about 20 and 27 times to National Ambient Air Quality Standards (NAAQS). For Diwali-2011, the increase in PM10 and PM2.5 mass concentrations was much less with their peaks of 600 and of 390 μg/m3 respectively, as compared to the background concentrations. Contrary to previous reports, firework display was not found to strongly influence the NOx, and O3 mixing ratios, with the increase within the observed variability in the background. CO mixing ratios showed an increase. We show that the large difference in 2010 and 2011 pollutant concentrations is controlled by weather parameters.    

19.  Effects of chronic and subtoxic chlorobenzenes on adrenocorticotrophic hormone release  
   Zsolt Molnár  Regina Pálföldi  Anna László  Marianna Radács  Krisztián Sepp  Péter Hausinger  László Tiszlavicz  Zsuzsanna Valkusz  Márta Gálfi《环境科学学报(英文版)》,2015年第27卷第8期
   Many environmental chemicals and pesticides have been found to alter neuroendocrine communication in exposed biological objects. The environmental loads have primary and secondary effects that can alter the homeostatic regulation potential. Since it is difficult to avoid human exposition, a potentially important area of research to develop in vivo and in vitro experimental models. In this context, the primary aim of this study was to demonstrate the effects of chlorobenzenes on adrenocorticotrophic hormone (ACTH) release. In our experimental study, male Wistar rats were exposed to 0.1, 1.0 and 10 μg/b.w. (body weight) kg of 1,2,4- trichlorobenzene and hexachlorobenzene (ClB) mix via gastric tube for 30, 60 or 90 days. At the endpoints of the experiment blood samples were taken and animals were decapitated. Primary, monolayer adenohypophysis cell cultures were prepared by enzymatic and mechanical digestion. The ACTH hormone content in serum and supernatant media was measured by immuno-chemiluminescence assay. The Mg2 +-dependent ATPase activity was determined by modified method of Martin and Dotty. Significant differences were detected in the hormone release between the control and treated groups. The hormone release was enhanced characteristically in exposed groups depending upon the dose and duration of exposure. The Mg2 +-ATPase activity enhanced after chronic and subtoxic ClB exposition. Light microscopy revealed that the adenohypophysis seemed to be more abundant. Results indicate that Wistar rats exposed to subtoxic ClB have direct and indirect effects on hypothalamus–hypophysis–adrenal axis.    

20.  Stable-isotope probing of bacterial community for dissolved inorganic carbon utilization in Microcystis aeruginosa-dominated eutrophic water  
   Weiguo Zhang  Jiangye Li  Chengcheng Wang  Xue Zhou  Yan Gao  Zhongjun Jia《环境科学学报(英文版)》,2019年第31卷第5期
   Dissolved inorganic carbon (DIC) is an important source of carbon in aquatic ecosystems, especially under conditions of increased frequency of cyanobacterial bloom. However, the importance of bacteria in direct or indirect utilization of DIC has been widely overlooked in eutrophic freshwater. To identify the functional bacteria that can actively utilize DIC in eutrophic freshwater during cyanobacterial bloom, stable-isotope probing (SIP) experiments were conducted on eutrophic river water with or without inoculation with cyanobacteria (Microcystis aeruginosa). Our 16S rRNA sequencing results revealed the significance of Betaproteobacteria, with similar relative abundance as Alphaproteobacteria, in the active assimilation of H13CO3? into their DNA directly or indirectly, which include autotrophic genera Betaproteobacterial ammonia-oxidizing bacteria. Other bacterial groups containing autotrophic members, e.g. Planctomycetes and Nitrospira, also presented higher abundance among free-living bacteria in water without cyanobacteria. Microcystis aggregates showed a preference for some specific bacterial members that may utilize H13CO3? metabolized by Microcystis as organic matter, e.g. Bacteroidetes (Cytophagales, Sphingobacteriales), and microcystin-degrading bacteria Betaproteobacteria (Paucibacter/Burkholderiaceae). This study provides some valuable information regarding the functional bacteria that can actively utilize DIC in eutrophic freshwater.    

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