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Trichloroethylene (TCE) is the most ubiquitous halogenated organic pollutant in the environment, it is one of the 129 priority control pollutants. In order to clarify the influence of TCE on microorganisms and nitrogen transformation in Mollisol is the core purpose of this study. Results showed that 10 mg kg−1 TCE is the concentration limit of ammonification in Mollisol. When the concentration of TCE reached 10 mg kg−1 and the effect lasted for over 7 days, the process of ammonia oxidation to nitric acid in Mollisol will be affected. TCE affected the process of nitrate (NO3−) transformation into nitrite (NO2−) by affecting the activity of nitrate reductase, thereby affected the denitrification process in soil. When the concentration of TCE is more than 10 mg kg−1 it reduced the ability of soil microorganisms to obtain nitrogen, thereby affecting soil nitrogen transformation. RDA (Redundancy analysis) showed that the activity of nitrate reductase and the number of nitrifying bacteria and denitrifying bacteria in soil was negatively correlated with the incubation of TCE. In addition, soil nitrate reductase, nitrite reductase, peroxidase activity, ammonifying bacteria, nitrifying bacteria and denitrifying bacteria were negatively correlated with TCE concentration. Beyond that PICRUSt (Phylogenetic Investigation of Communities by Reconstruction of Unobserved States) of functional gene structure depend on KEGG (Kyoto Encyclopedia of Genes and Genomes) showed that 20 mg kg−1 TCE significantly inhibited the metabolism of energy and other substances in Mollisol. Based on the above, it is found that TCE significantly affected nitrification and denitrification in Mollisol, thus the nitrogen transformation in Mollisol was affected by TCE contamination.

Trichloroethylene (TCE) is one of the most common groundwater pollutants. It is carcinogenic, teratogenic, mutagenic and poses a serious threat to human health and the environment. Therefore, reducing the environmental toxicity of TCE is of great significance. Anaerobic sludge was cultured and acclimated in an upflow anaerobic sludge blanket (UASB) reactor in this study. The Chemical Oxygen Demand (COD) concentration of the influent was approximately 2500 mg L−1, and the TCE concentration of the influent ranged from 1.46 mg L−1 to 73 mg L−1. After biodegradation of the anaerobic microflora, the COD removal rate was approximately 85%, and the TCE removal rate was over 85%. The microbial community of anaerobic sludge was analysed by 16 S rDNA clone libray and 454 high-throughput sequencing. Through analysis of the sequencing results, we found that there were a variety of acid-forming bacteria, anaerobic dechlorinating bacteria, and methanogenic bacteria. Based on the analysis of microflora function, it was speculated that the TCE metabolic pathway took place in UASB reactors. Desulfovibrio and Syntrophobacter provided an anaerobic environment, and acid-forming bacteria metabolise organic compounds into hydrogen. With Dehalobacter and Geobacter, TCE as an electron acceptor is dechlorinated and reduced under the anaerobic environment, in which hydrogen acts as an electron donor. By this, we clarified the metabolic pathway for improving TCE bioremediation.

Atrazine as a kind of herbicide could cause damage to the sensitive plants. Though plant growth promoting rhizobacteria (PGPR) have been proven with the potential to enhance the resistance of plants against various abiotic stresses, whether it could alleviate phytotoxicity caused by atrazine is sill unclear. In present study, the effects of strain Pseudomonas chlororaphis PAS18, a kind of PGPR enable to produce indole-3-acetic acid (IAA), on the growth and physiological responses of Pennisetum americanum (L.) K.Schum seedlings were investigated under three different levels (0, 20 and 100 mg kg−1) of atrazine in pot experiment. The results suggest that strain PAS18 could alleviate the growth and physiological interference caused by 20 mg kg−1 of atrazine. Physiological analysis showed strain PAS18 could further decrease the damaged extent of photosystem II, superoxide radical level and malondialdehyde content of test plant via up-regulating psbA expression, enhancing superoxide dismutase activity and reducing atrazine accumulation in the test plant. Moreover, ion flux measurements suggest that IAA could alleviate the Ca2+ exflux state of the test plant which caused by atrazine stress. Hence, it is plausible that strain PAS18 could alleviate atrazine-induced stress to P. americanum by enhancing the photosystem II repair and antioxidant defense ability as well as balancing the Ca2+ flux.

Heavy metals and pesticides often coexist in contaminated water, while their potential competition behaviors make the adsorptive removal more challenging. Thus, decorating an adsorbent with independent functional sites could be a promising alternative to radically prevent the competitive process for improving the adsorption performance. Herein, β-cyclodextrin functionalized rice husk-based cellulose (β-CD@RH-C) was designed and applied for synchronous removal of atrazine and Pb(II). The characterization results supported the successful grafting of β-cyclodextrin onto the cellulose. The β-CD@RH-C presented a pH-dependent adsorption performance for Pb(II) with a theoretical monolayer adsorption capacity of 283.00 mg/g, while was mostly unrelated to pH for atrazine adsorption with a heterogeneous uptake of 162.21 mg/g in the mono-component system. Most importantly, the β-CD@RH-C could efficiently achieve simultaneous removal of atrazine and Pb(II) via avoiding their competitive behaviors, which was due to the different adsorption mechanisms for atrazine (i.e. host-guest interaction) and Pb(II) (i.e. complexation and electrostatic interaction). Moreover, the adsorbed atrazine and Pb(II) could be sequentially desorbed with slight decrease in the adsorption performance of β-CD@RH-C even after four cycles in the atrazine-Pb(II) multi-component system. All these results suggested β-CD@RH-C to be a tailored adsorbent with high-performance elimination of co-existing heavy metals and organic pollutants in water.

Ca-based magnetic bamboo-derived hydrochar described as Ca-MBHC was synthesized by one-pot pyrolysis, and was applied to remediation of lead (Pb) and tetracycline (TC) polluted water. Characterizations not only attested the loading of CaCO3 and Fe0 onto the hydrochar, but also demonstrated the magnetism of Ca-MBHC. Adsorption kinetic experiments showed that the Ca-MBHC could eliminate Pb(II) and TC during a wide range of pH, and appeared rapid uptake equilibrium within 240 and 60 min for Pb(II) and TC, severally. Adsorption isotherm experiments showed that the Ca-MBHC possessed highest adsorption of 475.58 mg/g concerning Pb(II), and heterogeneous uptake of 142.44 mg/g for TC. Furthermore, the Ca-MBHC could achieve Pb(II) binding owing to complexation, reduction, ion exchange and electrostatic attraction, whereas the TC uptake might be related to π-π stacking reciprocities, pore filling and hydrogen bonding. Overall, the Ca-MBHC could be viewed as an excellent adsorbent for scavenging Pb(II) and tetracycline from water.

The primary purpose of this study was to systematically explore the complete metabolic pathway and tolerance mechanism of strain DNB-S1 to dibutyl phthalate (DBP), and the effect of DBP on energy metabolism of DNB-S1. Here, DNB-S1, a strain of Pseudomonas sp. that was highly effective in degrading DBP, was identified, and differentially expressed metabolites and metabolic networks of DBP were studied. The results showed that the differentially expressed metabolites were mainly aromatic compounds and lipid compounds, with only a few toxic intermediate metabolites. It speculated that phthalic acid, salicylic acid, 3-hydroxybenzoate acid, 3-Carboxy-cis, cis-muconate, fumarypyravate were intermediate metabolites of DBP. Their up-regulation indicated that there were two metabolic pathways in the degradation of DBP (protocatechuate pathway and gentisate pathway), which had been verified by peak changes at 290 nm, 320 nm, 330 nm, and 375 nm in the enzymatic method. Also, aspartate, GSH, and other metabolites were up-regulation, indicating that DNB-S1 had a high tolerance to DBP and maintained cell homeostasis, which was also one of the essential reasons to ensure the efficient degradation of DBP. Altogether, this study firstly proposed two pathways to degrade DBP and comprehensively explored the effect of DBP on the metabolic function of DNB-S1, which enriched the study of microbial metabolism of organic pollutants, and which provided a basis for the application of metabolomics.

This study was aim to investigate the interaction between soil-derived dissolved organic matter (DOM) and atrazine as a kind of pesticides during the sorption process onto black soil. According to the experimental data, the adsorption capacity of Soil + DOM, Soil and DOM were 41.80, 31.45 and 9.35 mg kg−1, separately, which indicated that DOM significantly enhanced the adsorption efficiency of atrazine by soil. Data implied that the pseudo-second-order kinetic equation could well explain the adsorption process. The adsorption isotherms (R2 > 0.99) had a satisfactory fit in both Langmuir and Freundlich models. Three-dimensional excitation-emission matrix (3D-EEM), synchronous fluorescence, two-dimensional correlation spectroscopy (2D-COS) and Fourier transform infrared spectroscopy (FT-IR) were selected to analyze the interaction between DOM and atrazine. 3D-EEM showed that humic acid-like substances were the main component of DOM. The fluorescence of DOM samples were gradually quenched with the increased of atrazine concentrations. Synchronous fluorescence spectra showed that static fluorescence quenching was the main quenching process. 2D-COS indicated that the order of the spectral changes were as following: 336 nm > 282 nm. Furthermore, the fluorescence quenching of humic-like fraction occurred earlier than that of protein-like fraction under atrazine surroundings. FT-IR spectra indicated that main compositions of soil DOM include proteins, polysaccharides and humic substances. The findings of this study are significant to reveal DOM played an important role in the environmental fate of pesticides during sorption process onto black soil and also provide more useful information for understanding the interaction between DOM and pesticides by using spectral responses.

Pile barriers as an effective method for isolating ambient vibration have been used in practical engineering for many decades. However, the study of multiple rows of pile barriers in satura...

Cadmium is highly poisonous to mammals and related water pollution incidents are increasing world-widely. Here, the clean-up of trace Cd(II) by a combined process of microwave-functionalized rice husk (RHMW-M) and poly aluminium chloride (PAC) was investigated for the first time, with the exploration of removal mechanism and efficacy. Microwave irradiation was found to be a new approach to achieve the functionalized procedure, which could decrease the processing time from 2.5 h to 390 s with the Cd(II) uptake of the outcome product soaring from 137.16 mg/g to 191.32 mg/g. The ultra-rapidly prepared RHMW-M exhibited a fast adsorption equilibrium within 30 min over a wide pH range of 5.0–8.0, and the FT-IR and XPS studies confirmed that both ion exchange and chelation were functioned in the Cd(II) uptake process. Controlled by the turbidity threshold of drinking water treatment plant, the feasible dosage of RHMW-M in the absence and presence of 30 mg/L PAC increased from 30 to 760 mg/L, which could effectively deal with the trace Cd(II) at the concentration from 33 μg/L up to 0.933 mg/L, exhibiting much better performance than traditional alkali precipitation. Predictably, this simple and scalable RHMW-M/PAC system could afford a promising end-of-pipe solution for heavy-metal contamination.

Pile barriers have been broadly used to decrease the effect of ground vibration generated by machines or traffic. However, so far, the research about the model test of vibration isolation of pile barriers is very few. In the present paper, the basic properties of the soil in the concrete model box are determined by the basic properties test of the soil firstly. Secondly, through the model tests with two types of piles under different vibration frequencies, the influences of different factors on the vibration isolation effect of pile barriers are studied. The results show that the multi-row pile barriers can effectively isolate the vibration. The main factors influencing the isolation effect are the pile diameter, the number of rows of piles and the vibration wave frequency.

Herein, β–cyclodextrin (β–CD) was efficiently grafted onto rice husk-based celluloses using different cross-linking agents of epichlorohydrin (EPI) and glutaraldehyde (GA). By feat of microwave irradiation, the functionalization procedure was completed in 17 min, and the synthesized RH EPI MW β-CD and RH GA MW β-CD exhibited fast adsorption equilibrium for Pb(II) within 20 min, excellent monolayer adsorption capacities of 216.06 and 279.08 mg g−1 across an extensive pH scope of 3.0–6.0, unaffected affinity to Pb(II) during the existence of co-existing ions, superior reusability with over 81% and 87% of Pb(II) uptake sustained for four adsorption-desorption cycles. Thermodynamic parameters implied that the uptake process of Pb(II) occurred spontaneously (−ΔG0) with an endothermic characteristic (+ΔH0). Furthermore, electrostatic attraction and complexation were demonstrated to enhance the Pb(II) uptake onto the RH EPI MW β-CD and RH GA MW β-CD. In fix-bed columns, these two adsorbents also efficiently eliminated Pb(II) under various flow rates with experimental breakthrough curves well simulated by Thomas and Yoon-Nelson models. Significantly, the RH EPI MW β-CD and RH GA MW β-CD could effectively purify acid battery effluent containing Pb(II) for meeting regulatory requirement. Overall, the fast fabrication, excellent adsorption and recycling performance facilitate the development of tailored adsorbents for Pb(II) elimination in wastewater.

It is well established that the tumor necrosis factor-α (TNF-α) plays a dominant role in rheumatoid arthritis (RA). Calcium channel is recently reported to be closely associated with various inflammatory diseases. However, whether chronic calcium channel blocker verapamil plays a role in RA still remains unknown. To investigate the role of verapamil in antagonizing TNF-α-mediated inflammation reaction and the underlying mechanisms, bone marrow-derived macrophages (BMDM) cells were cultured with stimulation of TNF-α, in the presence or absence of verapamil. Inflammation-associated cytokines, including IL-1, IL-6, inducible nitric oxide synthase 2 (NOS-2), and cyclooxygenase-2 (COX-2), were assessed, and verapamil suppressed TNF-α-induced expression of inflammatory cytokines. Furthermore, collagen-induced arthritis (CIA) mice models were established, and arthritis progression was evaluated by clinical and histological signs of arthritis. Treatment of verapamil attenuated inflammation as well as joint destruction in arthritis models. In addition, activity of NF-kB signaling pathway was determined both in vitro and in mice arthritis models, and verapamil inhibited TNF-α-induced activation of NF-kB signaling both in vitro and in mice models. Collectively, chronic calcium channel blocker verapamil may shed light on treatment of inflammatory arthritis and provide a potential therapeutic instrument for RA in the future.

Periodic structures often fabricated at the micro/nano-scale have opened new vistas in acoustic and electromagnetic wave manipulations due to band-gap properties. This study shows theoretically and experimentally that the propagation of destructive surface waves can also be controlled artificially using periodic wave barriers that modify the global properties of the background soil. To depict the attenuation property of surface waves, this study provides a complete dispersion analysis, the complex dispersion relation. Results show that, remarkably, the attenuation zone for surface waves includes not only the band gap but also other evanescent surface modes. This result agrees well with that in the experimental transmission spectra for both periodic trench barriers and periodic pile barriers. Due to their broadband attenuation performance, periodic wave barriers are expected to apply to vibration isolation in a wide range of systems.

Trichloroethylene (TCE), one of 129 kinds of priority pollutants, is the most common halogenated organic pollutant in the environment. To explore the changes in soil physicochemical properties and biological activities then clarify the effects of these factors on bacterial, fungal and actinomycetes communities in Mollisol under TCE stress is the significance of our research. The results indicated that when TCE concentration was greater than 10 mg kg−1, soil quality declined and soil decomposition of organic matter and cycling of mineral nutrients were inhibited through an effect on soil microbial biomass. Operational taxonomic units (OTUs) richness of the bacteria in Mollisol was altered by TCE contamination. The SChao1 and HShannon indices of bacterial communities in Mollisol decreased when 40 mg kg−1 TCE was applied. Meanwhile, the OTU richness of fungi in Mollisol was altered by TCE contamination. The HShannon indices of the fungal communities in Mollisol were inhibited by higher TCE concentrations (20 and 40 mg kg−1 TCE). TCE altered the content of some bacteria, fungi and actinomycetes involved in soil carbon and nitrogen cycling and metabolism, such as Acidobacteria, Proteobacteria, Planctomycetes, Chytridiomycota, Streptomycetales, Pseudonocardiales, Propionibacteriales and Rhizobiales, and thus influenced nutrient cycling and the process of energy metabolism in Mollisol. In addition, redundancy analysis (RDA) results indicated that physicochemical properties and biological activities under TCE contamination significantly affected soil microbial community composition thus confirming that TCE interfered with the carbon and nitrogen cycling and metabolism of soil microorganisms. The results of this study are of great importance for revealing the effects of TCE stress on the microbiological characteristics of Mollisol, and also provide more useful information for determining the potential ecological risk of organic pollutants in Mollisol.

Trichloroethylene (TCE) degradation and the variations of bacteria composition and structure in the up-flow anaerobic sludge blanket (UASB) reactor were investigated by increasing the operating temperature from 20 to 40 °C. The influent was supplemented with 36.5 mg/L of TCE. There was a rise in the chemical oxygen demand (COD) removal efficiency from 20 to 35 °C and a decline when temperature enhanced to 40 °C. It reached maximum at 35 °C. In addition, TCE removal efficiency increased with temperature varying from 20 to 35 °C, and it dropped dramatically to 78.38 % at 40 °C, which presumably because the genus of Dehalobacter, a kind of bacteria with the ability to dechlorinate TCE to the corresponding chlorinated products, was not detected at 40 °C according to sequencing results. The Illumina MiSeq platform was adopted to explore the bacteria composition and structure in response to temperature shifts. The results indicated that temperature impacted greatly on the dominance and presence of specific populations at different taxonomic levels. Importantly, the class Dehalococcoidia was detected from 25 to 40 °C, in which there were many well-known Dehalococcoides sp. strains that were capable of complete dechlorination of TCE to ethene. It also suggested the potential function of the dominant genera (non-dechlorinating bacteria and dechlorinating bacteria) in the reactor.

Dissolved organic matter (DOM) is the most active component in an environmental system. It can influence the chemical and structural characteristics of soil. In this work, three-dimensional excitation-emission matrix (3D-EEM) fluorescence spectroscopy, parallel factor analysis (PARAFAC), and two-dimensional correlation spectroscopy (2D-COS) integrated with synchronous fluorescence were used to explore the interaction between soil-derived DOM and Pb(II) during the soil sorption process. According to the data of batch sorption experiments, the adsorbing capacities of soil, soil + 5 mL DOM, and soil + 10 mL DOM were 16.96, 18.29, and 19.32 mg g−1, respectively, which indicated that DOM significantly enhanced the adsorption efficiency of Pb(II). The pseudo-second-order kinetic equation could well explain the adsorption process. The adsorbing data conformed to the isotherm of Langmuir adsorption. According to EEM-PARAFAC results, there are two major components from DOM. Protein-like substances were represented by component 1, and humic-like and fulvic-like substances were represented by component 2. Based on 3D-EEM, the results further showed that the intensities of component 1 and component 2 were obviously quenched with the increase of Pb(II) concentrations. The combined interpretations of the 2D-COS map for the DOM revealed that Pb(II) binding might occur sequentially in the order of humic-like fraction > protein-like fraction (346 > 282 nm). According to synchronous fluorescence spectra, static fluorescence quenching was the major process of quenching.

A limnetic peritrichous ciliate, Epistylis plicatilis Ehrenberg, 1831, was collected from a freshwater ditch beside Moshan Hill, Wuhan, China. Its morphology, infraciliature, and morphogenesis were investigated based on specimens examined in vivo, following staining with protargol and by scanning electron microscopy. The characteristics of the Wuhan population of E. plicatilis are as follows: 1) colonial, each colony typically comprising 30–50 individuals, with a dichotomously branched, noncontractile stalk; 2) fully expanded zooids measure 90–155 × 30–50 µm in vivo; 3) a series of 6 or 7 conspicuous folds appear in the posterior region of the zooid when it contracts; 4) single horseshoe-shaped macronucleus oriented transversely; 5) single contractile vacuole located in peristomial region on dorsal wall of infundibulum; 6) myoneme system comprises 20–24 longitudinal fibers, peristomial disk fibers as a wreath-like net and peristomial ring fibers; 7) narrowly spaced transverse striations on the surface of the body; 8) infundibular polykineties 1 and 2 are three-rowed, infundibular polykinety 3 is two-rowed; and 9) stomatogenesis is of the buccokinetal type; in the new oral apparatus, infundibular polykineties 2 and 3, the haplokinety, and the germinal kinety all originate from the germinal kinety of the parental oral apparatus whereas the polykinety and infundibular polykinety 1 originate from the parental haplokinety. An improved diagnosis of E. plicatilis is supplied. J. Morphol. 275:882–893, 2014. © 2014 Wiley Periodicals, Inc.

Rice husk, a surplus agricultural byproduct, was applied to the sorption of copper from aqueous solutions. Chemical modifications by treating rice husk with H3PO4increased the sorption ability of rice husk for Cu(II). This work investigated the sorption characteristics for Cu(II) and examined the optimum conditions of the sorption processes. The elemental compositions of native rice husk and H3PO4-treated rice husk were determined by X-ray fluorescence (XRF) analysis. The scanning electron microscopic (SEM) analysis was carried out for structural and morphological characteristics of H3PO4-treated rice husk. The surface functional groups (i.e., carbonyl, carboxyl, and hydroxyl) of adsorbent were examined by Fourier Transform Infrared Technique (FT-IR) and contributed to the adsorption for Cu(II). Adsorption isotherm experiments were carried out at room temperature and the data obtained from batch studies fitted well with the Langmuir and Freundlich models withR2of 0.999 and 0.9303, respectively. The maximum sorption amount was 17.0358 mg/g at a dosage of 2 g/L after 180 min. The results showed that optimum pH was attained at pH 4.0. The equilibrium data was well represented by the pseudo-second-order kinetics. The percentage removal for Cu(II) approached equilibrium at 180 min with 88.9% removal.

A controlled study was conducted to test the effect of land application with oxidation pond treatment sugar beet rinse water (SBRW) on soil chemical properties and on corn ( Zea mays L.) growth and yield. Samples were collected from each plot: pre-irrigation (provided reference “background” values), well water (WW) irrigation (served as the control) site and SBRW irrigation site. Soil chemical properties at different soil depths were measured. Compared with WW irrigation and pre-irrigation, the pH decreased at SBRW irrigation site and it resulted in an improvement of the contents of available nutrients in the soil layer (0–20 cm) due to SBRW with lower pH and a great quantity of nutrients. SBRW, characterized by high salinity, had little effect on soil salinity and sodicity. Principal component analysis (PCA) was used to evaluate the impact of SBRW irrigation on chemical properties of the whole soil profile and the results showed that exchangeable sodium percentage (ESP) changed not more obviously than available nutrients and cation exchange capacity (CEC). SBRW irrigation would make positive effect on corn growth and it could significantly improve corn's yield and dry matter. As silty clay's low potential for leaching and hydraulic conductivity, leachates did not cause any pollution in terms of nutrient and salinity release to groundwater. These results confirmed that besides its role as irrigant, SBRW might also serve as a “liquid fertilizer” for soil and corn.

Dynamic compaction method reinforced foundation and has advantages in civil engineering: obvious effect, simple equipment, construction is convenient, economy and easy, etc. But the adverse effects that the dynamic compaction vibration on environment and building are also serious. In this paper, the horizontal and vertical earth pressure transfer laws were got through the model test. And the horizontal and vertical earth pressure decaying formulas, which consider ramming energy and distance to tamping point two factors, were fitted. The research results provide theoretical basis for further study of the effect of dynamic stress produced by the dynamic compaction to surrounding buildings.

The effects of chemical oxygen demand and nitrogen (COD/N) ratio and dissolved oxygen concentration (DO) on simultaneous nitrification and denitrification (SND) were investigated using an airlift internal circulation membrane bioreactor (AIC-MBR) with synthetic wastewater. The results showed that the COD efficiencies were consistently greater than 90% regardless of changes in the COD/N ratio. At the COD/N ratio of 4.77 and 10.04, the system nitrogen removal efficiency became higher than 70%. However, the nitrogen removal efficiency decreased to less than 50%, as the COD/N ratio shifted to 15.11. When the operating DO concentration was maintained at 1.0 mg/L in AIC-MBR, a satisfying SND was achieved. Either low or high DO concentration could restrain SND.

The study reported the upflow anaerobic sludge blanket (UASB) reactor performance in treating wastewater containing trichloroethylene (TCE) and characterized variations of bacteria composition and structure by changing the pH from 6.0 to 8.0. A slightly acidic environment (pH < 7.0) had a greater impact on the TCE removal. Illumina pyrosequencing was applied to investigate the bacterial community changes in response to pH shifts. The results demonstrated that pH greatly influenced the dominance and presence of specific populations. The potential TCE degradation pathway in the UASB reactor was proposed. Importantly, the genus Dehalobacter which was capable of reductively dechlorinating TCE was detected, and it was not found at pH of 6.0, which presumably is the reason why the removal efficiency of TCE was the lowest (80.73 %). Through Pearson correlation analyses, the relative abundance of Dehalobacter positively correlated with TCE removal efficiency (R = 0.912). However, the relative abundance of Lactococcus negatively correlated with TCE removal efficiency according to the results from Pearson correlation analyses and redundancy analysis (RDA).

A limnetic peritrichous ciliate, Epistylis plicatilis Ehrenberg, 1831, was collected from a freshwater ditch beside Moshan Hill, Wuhan, China. Its morphology, infraciliature, and morphogenesis were investigated based on specimens examined in vivo, following staining with protargol and by scanning electron microscopy. The characteristics of the Wuhan population of E. plicatilis are as follows: 1) colonial, each colony typically comprising 30-50 individuals, with a dichotomously branched, noncontractile stalk; 2) fully expanded zooids measure 90-155 × 30-50 µm in vivo; 3) a series of 6 or 7 conspicuous folds appear in the posterior region of the zooid when it contracts; 4) single horseshoe-shaped macronucleus oriented transversely; 5) single contractile vacuole located in peristomial region on dorsal wall of infundibulum; 6) myoneme system comprises 20-24 longitudinal fibers, peristomial disk fibers as a wreath-like net and peristomial ring fibers; 7) narrowly spaced transverse striations on the surface of the body; 8) infundibular polykineties 1 and 2 are three-rowed, infundibular polykinety 3 is two-rowed; and 9) stomatogenesis is of the buccokinetal type; in the new oral apparatus, infundibular polykineties 2 and 3, the haplokinety, and the germinal kinety all originate from the germinal kinety of the parental oral apparatus whereas the polykinety and infundibular polykinety 1 originate from the parental haplokinety. An improved diagnosis of E. plicatilis is supplied.

In order to solve the increasing water environmental problems caused by NPSP, we selected Ashi River Basin of Acheng section as a research subject and study it's characteristics of NPSP. The results showed that the primary pollutants were TN and TP, and the primary pollution source was crop farming and stockbreeding .Then we put forward effective measures for prevention and control of NPSP.

This paper studies how chemical modification influences the Saccharomyces cerevisiae adsorption on copper ion and the desorption of nitric acid, and carries out infrared spectrum analysis of native, adsorbing and desorbing saccharomyces cerevisiae. Results show that carboxyl and amino group in Saccharomyces cerevisiae play an important role in the process of adsorbing Cu(II). The adsorption on Cu(II) by Saccharomyces cerevisiae is mainly the process of surface adsorption. The process of biosorption on heavy metals is mainly reversible adsorption; however, there still exists irreversible adsorption. FTIR analysis further indicates that carboxyl and hydroxyl adsorption on Cu(II) is reversible adsorption, which amino group adsorption on Cu(II) is irreversible adsorption.

This paper demonstrates the Pb(2+) adsorption capacity and adsorption rate of Saccharomyces cerevisiae by both static and dynamic testing to verify its feasibility as a heavy metal bio-absorbent in wastewater treatment. The static testing was divided into two parts. First, we tested S. cerevisiae by itself, and then we tested immobilized S. cerevisiae. In static testing of the non-immobilized S. cerevisiae, the Pb(2+) adsorption capacity and adsorption rate increased up to 6.52 mg/g and 52.94%, respectively, with time. After immobilization, the Pb(2+) adsorption capacity and adsorption rate reached 10 mg/g and 80%, respectively. In dynamic testing, the optimal saturated adsorption capacity of immobilized S. cerevisiae for Pb(2+) was 6.64 mg/g. In addition to the static and dynamic testing of adsorption capacity and rate, we used SEM imaging to analyze the mechanics of adsorption, and the images showed that the cell wall played the major roll in Pb(2+) adsorption.