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Pseudomonas ***-1,a newly isolated and highly efficient atrazine-degrading bacterium,and optimization of biodegradation using response surface methodology

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Journal of environmental Sciences 2017年第4期29卷 152-159页

作者： Xinyue Zhao Li Wang Fang Ma Shunwen Bai Jixian Yang Shanshan Qi State Key Laboratory of Urban Water resource and environment Harbin Institute of Technology

Atrazine, a widely used herbicide, is increasing the agricultural production effectively, while also causing great environmental concern. Efficient atrazine-degrading bacterium is necessary to removal atrazine rapidly to keep a safe environment. In the present study, a new atrazine-degrading strain ZXY-1, identified as Pseudomonas, was isolated. This new isolated strain has a strong ability to biodegrade atrazine with a high efficiency of 9.09 mg/L/***, p H, inoculum size and initial atrazine concentration were examined to further optimize the degradation of atrazine, and the synthetic effect of these factors were investigated by the response surface methodology. With a high quadratic polynomial mathematical model（R^2= 0.9821） being obtained, the highest biodegradation efficiency of 19.03 mg/L/hr was reached compared to previous reports under the optimal conditions（30.71°C, pH 7.14, 4.23%（V/V） inoculum size and 157.1 mg/L initial atrazine concentration）.Overall, this study provided an efficient bacterium and approach that could be potentially useful for the bioremediation of wastewater containing atrazine.

关键词： Pseudomonas sp.ZXY-1 Atrazine biodegradation Response surface methodology Central composite design Optimization design

A restudy of Oryctocephalus indicus (Reed,1910)

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Progress in Natural Science:Materials International 2006年第11期16卷 1177-1182页

作者： ZHAO Yuanlong~1**, YUAN Jinliang~2, PENG Shanchi~ 2,3 , YANG Xinglian~1, PENG Jin~1, LIN Jihpai~4, and GUO Qingjun~5(1. College of resource and environment of Guizhou University, Guiyang 550003, China 2. Nanjing Institute of Geology and Palaeontology, Chinese Academy of Sciences, Nanjing 210008, China 3. State Key Laboratory of Papaeobiology and Stratigraphy, Nanjing Institute of Geology and Palaeontology, Nanjing 210008, China 4. department of Geological Science, Ohio State University, Columbus, OH 43210, USA 5. Institute of Geochemistry, Chinese Academy of Sciences, Guiyang 550002, China) College of resource and environment of Guizhou University Guiyang 550003 China

Restudy on morphology of Oryctocephalus indicus (Reed, 1910), based on specimens from Guizhou, China and Nevada USA, suggests that the subspecies regarded previously as Oryctocephalus indicus indicus (Reed, 1910), O. indicus latus Zhao et Yuan 2002, and O. indicus kobayashi Saito, 1934, are synonymous, and Oryctocephalus americanus Sundberg et McCollum, 2003 is a similar form of O. indicus. Oryctocephalus indicus is rediagnosed as having a glabella that is subconical in outline and tapering forward slightly; a thorax that comprises 12 segments, and a small pygidium that bears 2—3 axial rings with a terminal piece and a postaxial ridge. Oryctocephalus indicus is widely distributed in eastern Guizhou and ranges through a great interval of Kaili Formation. Its first appearance is almost identical with these events of trilobite extinction-recovery occurring at the end of the Early Cambrian, the alternation of acritach assemblages, the change of trace elements (REE) and stable isotopes (carbon) at the Wuliu-Zengjiaya section. As one of the key forms for defining the traditional Lower-Middle Cambrian boundary (the base of Cambrian Series 3 and Stage 5 in the new Cambrian chronstratigraphic standard), O. indicus has received detailed study and has more advantages than other species such as Ovatoryctocara granulata Tchernysheva, 1962 or Arthricocephalus chauveaui Bergeron, 1899.

关键词： Oryctocephalus indicus restudy Kaili Formation Cambrian Guizhou China.

Influence of phenol on ammonia removal in an intermittent aeration bioreactor treating biologically pretreated coal gasification wastewater

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Journal of environmental Sciences 2016年第5期28卷 99-105页

作者： Chunyan Xu Hongjun Han Shengyong Jia Qian Zhao State Key Laboratory of Urban Water resource and environment Harbin Institute of Technology

A laboratory-scale intermittent aeration bioreactor was investigated to treat biologically pretreated coal gasification wastewater that was mainly composed of NH_3-N and *** results showed that increasing phenol loading had an adverse effect on NH_3-N removal;the concentration in effluent at phenol loading of 40 mg phenol/（L·day） was 7.3 mg/L, 36.3%of that at 200 mg phenol/（L·day）. The enzyme ammonia monooxygenase showed more sensitivity than hydroxylamine oxidoreductase to the inhibitory effect of phenol, with32.2% and 10.5% activity inhibition, respectively at 200 mg phenol/（L·day）. Owing to intermittent aeration conditions, nitritation-type nitrification and simultaneous nitrification and denitrification（SND） were observed, giving a maximum SND efficiency of 30.5%.Additionally, ammonia oxidizing bacteria（AOB） and denitrifying bacteria were the main group identified by fluorescent in situ hybridization. However, their relative abundance represented opposite variations as phenol loading increased, ranging from 30.1% to 17.5%and 7.6% to 18.2% for AOB and denitrifying bacteria, respectively.

关键词： Coal gasification wastewater Nitritation-type nitrification Denitrification Fluorescent in situ hybridization Phenol

Towards a better hydraulic cleaning strategy for ultrafiltration membrane fouling by humic acid: Effect of backwash water composition

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Journal of environmental Sciences 2016年第5期28卷 177-186页

作者： Haiqing Chang Heng Liang Fangshu Qu Jun Ma Nanqi Ren Guibai Li State Key Laboratory of Urban Water resource and environment Harbin Institute of Technology

As a routine measurement to alleviate membrane fouling, hydraulic cleaning is of great significance for the steady operation of ultrafiltration（UF） systems in water treatment processes. In this work, a comparative study was performed to investigate the effects of the composition of backwash water on the hydraulic cleaning performance of UF membranes fouled by humic acid（HA）. Various types of backwash water, including UF permeate, Milli-Q water, Na Cl solution, CaCl_2 solution and HA solution, were compared in terms of hydraulically irreversible fouling index, total surface tension and residual HA. The results indicated that Milli-Q water backwash was superior to UF permeate backwash in cleaning HA-fouled membranes, and the backwash water containing Na＋or HA outperformed Milli-Q water in alleviating HA fouling. On the contrary, the presence of Ca^（2＋） in backwash water significantly decreased the backwash efficiency. Moreover, Ca^（2＋） played an important role in foulant removal, and the residual HA content closely related to the residual Ca^（2＋） *** analysis suggested that the backwash process may involve fouling layer swelling, ion exchange, electric double layer release and competitive complexation. Ion exchange and competitive complexation played significant roles in the efficient hydraulic cleaning associated with Na＋and HA, respectively.

关键词： Ultrafiltration Membrane fouling Hydraulic cleaning Backwash water composition Humic acid

Nitrogen removal from coal gasification wastewater by activated carbon technologies combined with short-cut nitrogen removal process

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Journal of environmental Sciences 2014年第11期26卷 2231-2239页

作者： Qian Zhao Hongjun Han Baolin Hou Haifeng Zhuang Shengyong Jia Fang Fang State Key Laboratory of Urban Water resource and environment Harbin Institute of Technology

A system combining granular activated carbon and powdered activated carbon technologies along with shortcut biological nitrogen removal （GAC-PACT-SBNR） was developed to enhance total nitrogen （TN） removal for anaerobically treated coal gasification wastewater with less need for external carbon resources. The TN removal efficiency in SBNR was significantly improved by introducing the effluent from the GAC process into SBNR during the anoxic stage, with removal percentage increasing from 43.8%49.6% to 68.8%-75.8%. However, the TN removal rate decreased with the progressive deterioration of GAC adsorption. After adding activated sludge to the GAG compartment, the granular carbon had a longer service-life and the demand for external carbon resources became lower. Eventually, the TN removal rate in SBNR was almost constant at approx. 43.3%, as compared to approx. 20.0% before seeding with sludge. In addition, the production of some alkalinity during the denitrification resulted in a net savings in alkalinity requirements for the nitrification reaction and refractory chemical oxygen demand （COD） degradation by autotrophic bacteria in SBNR under oxic conditions. PACT showed excellent resilience to increasing organic loadings. The microbial community analysis revealed that the PACT had a greater variety of bacterial taxons and the dominant species associated with the three compartments were in good agreement with the removal of typical pollutants. The study demonstrated that pre-adsorption by the GAC-sludge process could be a technically and economically feasible method to enhance TN removal in coal gasification wastewater （CGW）.

关键词： Coal gasification wastewater Short-cut nitrogen removal Granular activated carbon PCR-DGGE Denitrification enhancement

Advanced treatment of biologically pretreated coal gasification wastewater by a novel heterogeneous Fenton oxidation process

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Journal of environmental Sciences 2015年第7期27卷 12-20页

作者： Haifeng Zhuang Hongjun Han Wencheng Ma Baolin Hou Shengyong Jia Qian Zhao State Key Laboratory of Urban Water resource and environment Harbin Institute of Technology

Sewage sludge from a biological wastewater treatment plant was converted into sewage sludge based activated carbon（SBAC） with Zn Cl2 as activation agent, which was used as a support for ferric oxides to form a catalyst（Fe Ox/SBAC） by a simple impregnation *** new material was then used to improve the performance of Fenton oxidation of real biologically pretreated coal gasification wastewater（CGW）. The results indicated that the prepared Fe Ox/SBAC significantly enhanced the pollutant removal performance in the Fenton process, so that the treated wastewater was more biodegradable and less toxic. The best performance was obtained over a wide p H range from 2 to 7, temperature 30°C, 15 mg/L of H2O2 and 1 g/L of catalyst, and the treated effluent concentrations of COD, total phenols,BOD5 and TOC all met the discharge limits in China. Meanwhile, on the basis of significant inhibition by a radical scavenger in the heterogeneous Fenton process as well as the evolution of FT-IR spectra of pollutant-saturated Fe Ox/BAC with and without H2O2, it was deduced that the catalytic activity was responsible for generating hydroxyl radicals, and a possible reaction pathway and interface mechanism were proposed. Moreover, Fe Ox/SBAC showed superior stability over five successive oxidation runs. Thus, heterogeneous Fenton oxidation of biologically pretreated CGW by Fe Ox/SBAC, with the advantages of being economical, efficient and sustainable, holds promise for engineering application.

关键词： Biologically pretreated coal gasification wastewater Heterogeneous Fenton oxidation Catalyst Biodegradability Mechanism

Quantitative structure–biodegradability relationships for biokinetic parameter of polycyclic aromatic hydrocarbons

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Journal of environmental Sciences 2015年第4期27卷 180-185页

作者： Peng Xu Wencheng Ma Hongjun Han Shengyong Jia Baolin Hou State Key Laboratory of Urban Water resource and environment Harbin Institute of Technology

Prediction of the biodegradability of organic pollutants is an ecologically desirable and economically feasible tool for estimating the environmental fate of chemicals. In this paper,stepwise multiple linear regression analysis method was applied to establish quantitative structure biodegradability relationship（QSBR） between the chemical structure and a novel biodegradation activity index（qmax） of 20 polycyclic aromatic hydrocarbons（PAHs）. The frequency B3LYP/6-311＋G（2df,p） calculations showed no imaginary values, implying that all the structures are minima on the potential energy surface. After eliminating the parameters which had low related coefficient with qmax, the major descriptors influencing the biodegradation activity were screened to be Freq, D, MR, EHOMOand To IE. The evaluation of the developed QSBR mode, using a leave-one-out cross-validation procedure, showed that the relationships are significant and the model had good robustness and predictive ability. The results would be helpful for understanding the mechanisms governing biodegradation at the molecular level.

关键词： Leave-one-out cross-validation Stepwise multiple linear regression Polycyclic aromatic hydrocarbons QSBR

A case study of aggregation behaviors of titanium dioxide nanoparticles in the presence of dodecylbenzene sulfonate in natural water

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Journal of environmental Sciences 2015年第10期27卷 84-92页

作者： Xin Du Xiuheng Wang Shijie You Qiuru Wang Xiaobo Gong State Key Laboratory of Urban Water resource and environment Harbin Institute of Technology

The present work aims to ascertain the mechanisms of surfactant（dodecylbenzene sulfonate; DBS） effects on the aggregation behaviors of TiO2 nanoparticles（TiO2-NPs） in natural water samples. Aggregation experiments were conducted at a TiO2-NPs concentration of 10 mg/L in deionized water and in natural water samples via dynamic light scattering and Zeta potential determination. Average attachment efficiency was calculated to compare the aggregation behaviors of nanoparticles in the two aqueous media. Results showed that the effects of DBS on aggregation could be interpreted by both Derjaguin–Landau–Verwey–Overbeek（DLVO） and non-DLVO mechanisms. In natural water samples,aggregation did not occur rapidly and was able to develop slowly under all conditions, and the roles of DBS were obvious at high DBS concentration owing to the impacts of inherent components of natural water samples, such as colloids and natural organic *** aggregation studies should concentrate on multi-factor, multi-colloidal and dynamic aspects under similar environmental conditions.

关键词： Titanium dioxide Nanoparticle Aggregation Dodecylbenzene sulfonate Natural water

QSAR Studies on 6-(1-Naphthylmethyl) Substituted S-DABO Derivatives as Novel Non-nucleoside HIV-1 Reverse Transcriptase Inhibitors

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Chinese Journal of Structural chemistry 2008年第10期27卷 1214-1222页

作者：殷丽琴余仕问姚凌峰何严萍谢小光 department of chemistry Yunnan University Key Laboratory of Medicinal chemistry for Natural resource(Yunnan University) Ministry of Education

The AM1 and B3LYP methods were employed to calculate the structural properties of 20 6-（1-naphthylmethyl） substituted S-DABO derivatives with β-carbonyl group on the C（2） side chain as novel potent non-nucleoside HIV-1 reverse transcriptase inhibitors. The correlation analysis （CA） and stepwise multiple regression analysis （SMR） were performed. The QSAR models indicate that the physicochemical parameters of Qc9, MRR1, ELUMO, ∏R2 and μ have significant influence on the activities of these derivatives. The substitution of hydrophobic R2 and bulky aromatic R1 to form a conjugated system with the frame of those S-DABO series compounds should be considered to design new potent compounds for anti-HIV-1.

关键词： S-DABO derivatives correlation analysis stepwise regression analysis QSAR LUMO