Long-term nitrogen and phosphorus removal,shifts of functional bacteria and fate of resistance genes in bioretention systems under sulfamethoxazole stress

To understand the long-term performance of bioretention systems under sulfamethoxazole (SMX) stress, an unplanted bioretention system (BRS) and two modified BRSs with coconut-shell activated carbon (CAC) and CAC/zero-valent-iron (Fe0) granules (CAC-BRS and Fe/CAC-BRS) were established. Both CAC-BRS and Fe/CAC-BRS significantly outperformed BRS in removing total nitrogen (TN)(CAC-BRS:82.48%; Fe/CAC-BRS:78.08%; BRS:47.51%), total phosphorous (TP)(CAC-BRS:79.36%; Fe/CAC-BRS:98.26%; BRS:41.99%),and...     

Investigation in the sorption mechanism and behavior of nano γ-Al2O3 for the removal of fluorine ions

研究了纳米γ-Al2O3吸附剂对氟离子的吸附行为,考查了吸附平衡时间、温度、溶液的pH等对吸附过程的影响.结果表明,在室温下,纳米γ-Al2O3对氟离子的吸附在3min基本达到平衡;在pH3～9范围内,吸附率达95%以上;吸附过程符合准二级反应动力学模型,其反应的表观活化能（Ea）为10.99kJ.mol-1;颗粒内扩散过程是吸附的主要控制步骤,而颗粒外扩散过程对吸附也有影响;吸附过程符合Langmuir、D-R等温模型,常温下,纳米γ-Al2O3对氟离子的平均吸附能为11.15kJ.mol-1.吸附反应的ΔGθ〈0,ΔHθ〉0,说明该吸附过程是自发的吸热反应.共存阴离子HCO3-和PO43-、阳离子Cu2＋对氟离子的吸附影响较大.纳米γ-Al2O3在动态和静态吸附实验中的除氟效果相近.     

Microstructure,corrosion behavior,and microhardness of plasma-sprayed W–Ni composite coatings

Commercial tungsten powder of average particle size 12 μm was mixed with 10 wt% Ni powder and plasma sprayed on a SUS304 stainless steel substrate. W–Ni composite coatings have been sprayed at different Ar plasma gas flow rates of 120, 150, and 170 l/min and different Ar carrier gas flow rates of 5, 8, and 10 l/min. The microstructure and phase structure of the sprayed coatings were investigated using a scanning electron microscope (SEM), X-ray diffraction (XRD), and an energy dispersive spectrometer (EDS). Corrosion tests were performed for the sprayed W–Ni coatings in a 3.5% NaCl solution using an electrochemical polarization method. It was found that the W–Ni coatings sprayed at a higher Ar gas flow rate showed higher corrosion resistance compared with coatings sprayed at a lower gas flow rate. A more positive value of the corrosion potential and a lower value of the corrosion current are observed for coatings sprayed at a higher Ar gas flow rate.     

Ecological rebuilding and land reclamation in surface mines inShanxi Province, China

ＩｎｔｒｏｄｕｃｔｉｏｎＡｓａｐｒｉｎｃｉｐｌｅｓｕｐｐｌｉｅｒｏｆｒａｗｍａｔｅｒｉａｌｓ ,ｔｈｍｉｎｉｎｇｉｎｄｕｓｔｒｙｉｎＣｈｉｎａｍｕｓｔｉｎｃｒｅａｓｅｉｔｓｏｕｔｐｕｔｔｏｍｅｅｔｔｈｅｅｖｅｒ ｉｎｃｒｅａｓｉｎｇｄｅｍａｎｄｓｆｏｒｅｃｏｎｏｍｉｃｄｅｖｅｌｏｐｍｅｎｔａｎｄ ｐｅｏｐｌｅ′ｓｅｘｐｅｃｔａｔｉｏｎｓ.Ｈｏｗｅｖｅｒ,ａｂｙ ｐｒｏｄｕｃｔｏｆｉｎｃｒｅａｓｅｄｍｉｎｉｎｇａｃｔｉｖｉｔｙｗｉｌｌｂｅａｎｉｎｃｒｅａｓｅｉｎｔｈｅａｍｏｕｎｔｏｆｄｅｓｐｏｉｌｅｄｌ…     

Impacts of climate change on development rate and production of corn in the northeastern China

In this paper, the impacts of climate change on development rate and production of corn in the northeastern China are discussed. The results show that the higher the temperature is, the faster the development rate will be. And the more the precipitation is, the slower the development rate will be. Of which, air temperature is the controlling factor of corn development rate. The influences of development rate on corn yield are remarkable. The impacts of development rate on production in first and last periods are great, and small in the middle two periods. The development rate is positive by relate with corn production from sowing to emergence stage and negative during other periods. So, it is very important to arrange a suitable sowing time for com cultivating in the northeastern China.     

Efficiency of white lupin in the removal of mercury from contaminated soils： Soil and hydroponic experiments

This study examined the ability of the white lupin to remove mercury (Hg) from a hydroponic system (Hg concentrations 0, 1.25, 2.5, 5 and 10 μmol/L) and from soil in pots and lysimeters (total Hg concentration (19.2 ± 1.9) mg/kg availability 0.07%, and (28.9 ± 0.4) mg/kg availability 0.09%, respectively), and investigated the accumulation and distribution of Hg in different parts of the plant. White lupin roots efficiently took up Hg, but its translocation to the harvestable parts of the plant was low. The Hg concentration in the seeds posed no risk to human health according to the recommendations of the World Health Organization, but the shoots should not be used as fodder for livestock, at least when unmixed with other fodder crops. The accumulation of Hg in the hydroponically-grown plants was linear over the concentration range tested. The amount of Hg retained in the roots, relative to the shoots, was almost constant irrespective of Hg dose (90%). In the soil experiments, Hg accumulation increased with exposure time and was the greater in the lysimeter than in the pot experiments. Although Hg removal was the greater in the hydroponic system, revealing the potential of the white lupin to extract Hg, bioaccumulation was the greatest in the lysimeter-grown plants; the latter system more likely reflects the true behaviour of white lupin in the field when Hg availability is a factor that limits Hg removal. The present results suggest that the white lupin could be used in long-term soil reclamation strategies that include the goal of profitable land use in Hg-polluted areas.     

Perfluoroalkyl acids(PFAAs) in urban surface water of Shijiazhuang,China: Occurrence,distribution,sources and ecological risks

It is extremely important to analyze the contaminative behaviors of Perfluoroalkyl acids(PFAAs) due to their serious threats to urban environments which are closely related to humans. Current study aimed to explore the distribution, source apportionment and ecological risk assessment of PFAAs in surface water from Shijiazhuang, China. The concentrations of ΣPFAAs ranged from 19.5 to 125.9 ng/L in the investigation area. Perfluorobutanesulfonic acid(PFBS) and perfluoropentanoic acid(PFPeA) were t...     

Role of sorbent surface functionalities and microporosity in 2,2’,4,4’-tetrabromodiphenyl ether sorption onto biochars

The study provides insight into the combined effect of sorbent surface functionalities and microporosity on2,2 ′,4,4 ′-tetrabromodiphenyl ether (BDE-47) sorption onto biochars. A series of biochars prepared underdifferent conditionswere used to test their sorption behaviorswith BDE-47. The extents of sorption behaviorswere parameterized in terms of the single-point adsorption equilibrium constant (Koc ) at three equilibrium concentration (C e ) levels (0.001Sw (solubility), 0.005Sw , and 0.05Sw )whichwasdetermined using the Freundlich model. To elucidate the concentration-dependentdominant mechanisms for BDE-47 sorption onto biochars, K ocwas correlatedwith four major parameters using multiple parameter linear analysis accompaniedwith significance testing. The results indicated that at low concentration (Ce = 0.001Sw ), the surface microporosity term,which represented a pore-filling mechanism, contributed significantly to this relationship,while as concentrationwas increased to higher levels, surface functionality related to surface adsorption began to take thedominant role,whichwas further confirmed by the results of Polanyi-based modeling. Given the above results, adual mode model based on Dubinin-Radushkevich andde Boer-Zwikker equationswas adopted to quantitatively assess the changes of significance of surface adsorption aswell as that of pore fillingwith sorption processdevelopment. In addition, UV spectra of four typical aromatic compoundswhich represented the key structural fragments of biochars before and after interactionswith BDE-47were analyzed todetermine the active functional groups and supply complementary evidence for thedominant interaction force for surface adsorption, based onwhich π-π electron-donor-acceptor interactionwas proposed to contribute greatly to surface adsorption.     

Trend surface analysis of forest landscape pattern in Guandishan forest region of Shanxi,China

１ＩｎｔｒｏｄｕｃｔｉｏｎＡｌｍｏｓｔａｌｏｆｌａｎｄｓｃａｐｅｓａｒｅｓｐａｔｉａｌｙｈｅｔｅｒｏｇｅｎｅｏｕｓｍｏｓａｉｃｓｏｆｌａｎｄｃｏｖｅｒｏｒｈａｂｉｔａｔ（Ｆｏｒｍａｎ，１９９５）．Ｔｈｅｓｐａｔｉａｌａｒａｎｇｅｍｅｎｔｏｒｓｐａｔ...     

Spatial variability of organochlorine pesticides （DDTs and HCHs） in surface soils from the alluvial region of Beijing, China

The spatial variability in the concentrations of 1,2,3,4,5,6-hexachlorocyclohexane (HCH) and 1,1,1-trichloro-2,2-bis-(p-chlorophenyl) ethane (DDT) in surface soils was studied on the basis of the analysis of 131 soil samples collected from the surface layer (0-20 cm depth) of the alluvial region of Beijing, China. The concentrations of total HCHs (including α-, β-, γ-, and δ-isomers) and total DDTs (i ncluding p,p'-DDT, p,p'-DDD, p,p'-DDE, and o,p'-DDT) in the surface soils tested were in the range from nondetectable to 31.72 μg/kg dry soil, with a mean value of 0.91, and from nondetectable to 5910.83 μg/kg dry soil, with a mean value of 32.13,respectively. It was observed that concentrations of HCHs in all soil samples and concentrations of DDTs in 112 soil samples were much lower than the first grade (50 μg/kg) permitted in "Environment quality standard for soils in China (GB15618-1995)". This suggests that the pollution due to organochlorine pesticides was generally not significant in the farmland soils in the Beijing alluvial region. In this study, the spatial distribution and trend of HCHs and DDTs were analyzed using Geostatistical Analyst and GS (513).Spatial distribution indicated how these pesticides had been applied in the past. Trend analysis showed that the concentrations of HCHs,DDTs, and their related metabolites followed an obvious distribution trend in the surface soils from the alluvial region of Beijing.     

Modeling the fate of paddy field pesticide in surface water and environmental risk assessment

ＩｎｔｒｏｄｕｃｔｉｏｎＭｉｃｒｏ ｏｒｇａｎｉｃｃｏｍｐｏｕｎｄｓｈａｖｅｂｅｅｎｉｄｅｎｔｉｆｉｅｄａｓｏｎｅｏｆｔｈｅｍａｉｎｒｉｓｋａｇｅｎｔｇｒｏｕｐｓｉｎｄｒｉｎｋｉｎｇｗａｔｅｒ.Ｉｎｓｕｒｆａｃｅｗａｔｅｒ,ａｇｒｉｃｕｌｔｕｒａｌｃｈｅｍｉｃａｌｓａｃｃｏｕｎｔｆｏｒａｌａｒｇｅｐａｒｔｏｆｔｈｅｏｒｇａｎｉｃｃｏｍｐｏｕｎｄｃｏｎｔｅｎｔｓ.ＩｎＥａｓｔａｎｄＳｏｕｔｈｅａｓｔＡｓｉａ ,ｉｎｃｌｕｄｉｎｇＣｈｉｎａａｎｄＪａｐａｎ ,ｃｕｌｔｉｖａｔｉｎｇｏｆｒｉｃｅ,ｔｈｅｍａｉ…     

Study on the mechanism of copper–ammonia complex decomposition in struvite formation process and enhanced ammonia and copper removal

Heavy metals and ammonia are difficult to remove from wastewater, as they easily combine into refractory complexes. The struvite formation method (SFM) was applied for the complex decomposition and simultaneous removal of heavy metal and ammonia. The results indicated that ammonia deprivation by SFM was the key factor leading to the decomposition of the copper–ammonia complex ion. Ammonia was separated from solution as crystalline struvite, and the copper mainly co-precipitated as copper hydroxide together with struvite. Hydrogen bonding and electrostatic attraction were considered to be the main surface interactions between struvite and copper hydroxide. Hydrogen bonding was concluded to be the key factor leading to the co-precipitation. In addition, incorporation of copper ions into the struvite crystal also occurred during the treatment process.     

Selective removal of heavy metals by Zr-based MOFs in wastewater: New acid and amino functionalization strategy

Zr-based metal-organic frameworks(MOFs) have been developed in recent years to treat heavy metals,e.g.hexavalent chromium Cr⁶⁺ pollution,which damages the surrounding ecosystem and threaten human health.This kind of MOF is stable and convenient to prepare,but has the disadvantage of low adsorption capacity,limiting its wide application.To this end,a novel formic acid and amino modified MOFs were prepared,referred to as FormUiO-66-NH₂.Due to the modification of formic acid,i...     

Changes of surface water pollution of Suzhou region:a case study in Taicang County, China

ＣｈａｎｇｅｓｏｆｓｕｒｆａｃｅｗａｔｅｒｐｏｌｕｔｉｏｎｏｆＳｕｚｈｏｕｒｅｇｉｏｎ：ａｃａｓｅｓｔｕｄｙｉｎＴａｉｃａｎｇＣｏｕｎｔｙ，ＣｈｉｎａＬｉＹｏｎｇ，ＸｕＲｕｉｗｅｉ，ＺｈａｎｇＳｈｕｉｍｉｎｇ，ＡｎＱｉｏｎｇ，ＪｉｎＷｅｉ，Ｄｕ...     

Removal of perfluorinated surfactants from wastewater by adsorption and ion exchange——Influence of material properties,sorption mechanism and modeling

Perfluorooctane sulfonate(PFOS) has attracted increasing concern in recent years due to its world-wide distribution, persistence, bioaccumulation and potential toxicity. The influence of sorbent properties on the adsorptive elimination of PFOS from wastewater by activated carbons, polymer adsorbents and anion exchange resins was investigated with regard to their isotherms and kinetics. The batch and column tests were combined with physicochemical characterization methods, e.g., N_2 physisorption, mercury porosimetry, infrared spectroscopy, differential scanning calorimetry, titrations, as well as modeling. Sorption kinetics was successfully modelled applying the linear driving force(LDF) approach for surface diffusion after introducing a load dependency of the mass transfer coefficient βs.The big difference in the initial mass transfer coefficient βs,0, when non-functionalized adsorbents and ion-exchange resins are compared, suggests that the presence of functional groups impedes the intraparticle mass transport. The more functional groups a resin possesses and the longer the alkyl moieties are the bigger is the decrease in sorption rate.But the selectivity for PFOS sorption is increasing when the character of the functional groups becomes more hydrophobic. Accordingly, ion exchange and hydrophobic interaction were found to be involved in the sorption processes on resins, while PFOS is only physisorptively bound to activated carbons and polymer adsorbents. In agreement with the different adsorption mechanisms, resins possess higher total sorption capacities than adsorbents. Hence, the latter ones are rendered more effective in PFOS elimination at concentrations in the low μg/L range, due to a less pronounced convex curvature of the sorption isotherm in this concentration range.     

Effects of sulfur dioxide on growth,gas exchange rate and leaf sulfur content of massion pine seedlings

Ｅｆｆｅｃｔｓｏｆｓｕｌｆｕｒｄｉｏｘｉｄｅｏｎｇｒｏｗｔｈ，ｇａｓｅｘｃｈａｎｇｅｒａｔｅａｎｄｌｅａｆｓｕｌｆｕｒｃｏｎｔｅｎｔｏｆｍａｓｓｉｏｎｐｉｎｅｓｅｅｄｌｉｎｇｓＹａｎｇＬｉａｎｇＵｎｉｔｅｄＧｒａｄｕａｔｅＳｃｈｏｏｌ，ＴｏｋｙｏＵｎ...     

Development and experience in the monitoring,assessment and control of environmentalpollutants in Hong Kong

The late start of environmental protection in Hong Kong was discussed in the light of problems encountered during the development of environmental protection legislation in Hong Kong for the past 20 years. The collaboration in monitoring and assessment of environmental pollutants between the University of Hong Kong and various governments were descrbed in parallel with the progress in environmental protection in Hong Kong. The developments of new analytical techniques for environmental monitoring and analysis is given and their application in environmental control described. The joint projects in assessment and control of environmental pollutants carried out in collaboration with local industries and other organizations within and without the university are given and discussed. The problems and possible solution facing Hong Kong in development control equipment for small scale industries are discussed and areas of development identified. The development and experience in the monitoring assessment and co     

Changes of surface water pollution of Suzhou region: a case study in Taicang County, China

Environmental pollution is a by product of industrialization when economy of a region is developing. China also suffers from such a problem, especially in the southern part like Suzhou region in Jiangsu Province. In this paper, data covering situations of surface water pollution and social and economic development showed that the surface water pollution in Taicang County, a typical economic zone of Suzhou region, is significantly correlated to the economic growth of this region     

Interactions of copper,cadmium and molybdenum in buffalo calves:the levels of trace element in blood,urine and tissues

Ten male buffalo calves were randomly allotted into five groups of two each. Four groups were fed with cadmium, molybdenum, cadmium-molybdenum, and copper-cadmium-molybdenum respectively for 130 days to determine the elements' metabolic interactions in calves. These results indicated that cadmium and molybdenum could increase the accumulation of molybdenum and cadmium in liver and kidneys in buffalo calves, but copper could not. reduce to normal the levels of molybdenum and cadmium in liver and kidneys caused by cadmium-molybdenum. In addition, we found the copper concentrations in liver and kindeys was significantly greater in treatment calves than in controls.     

Photodegradation of hydroxyfluorenes in ice and water: A comparison of kinetics,effects of water constituents,and phototransformation by-products

The photochemical behavior of organic pollutants in ice is poorly studied in comparison to aqueous photochemistry.Here we report a detailed comparison of ice and aqueous photodegradation of two representative OH-PAHs,2-hydroxyfluorene (2-OHFL) and 9-hydroxyfluorene (9-OHFL),which are newly recognized contaminants in the wider environment including colder regions.Interestingly,their photodegradation kinetics were clearly influenced by whether they reside in ice or water.Under the same simulated s...