Metal Valence State Modulation Strategy to Design Core@shell Hollow Carbon Microspheres@MoSe2/MoOx Multicomponent Composites for Anti-Corrosion and Microwave Absorption.

The exploitation of multicomponent composites (MCCs) has become the main pathway for obtaining advanced microwave absorption materials (MAMs). Herein, a metal valence state modulation strategy is proposed to tune the electromagnetic (EM) parameters and improve microwave absorption performances. Core@shell hollow carbon microspheres@MoSe2 and hollow carbon microspheres@MoSe2/MoOx MCCs with various mixed-valence states content are well-designed and produced by a simple hydrothermal reaction or/and heat treatment process. The results reveal that the thermal treatment of hollow carbon microspheres@MoSe2 in Ar and Ar/H2 leads to the in situ formation of MoOx and multivalence state, respectively, and the enhanced content of Mo4+ in the designed MCCs greatly boosts their impedance matching characteristics, polarization, and conduction loss capacities, which lead to their evidently improved EM wave absorption properties. Amongst, the as-prepared hollow carbon microspheres@MoSe2/MoOx MCCs achieve an effective absorption bandwidth of 5.80 GHz under a matching thickness of 1.97 mm and minimum reflection loss of -21.49 dB. Therefore, this work offers a simple and universal method to fabricate core@shell hollow carbon microspheres@MoSe2/MoOx MCCs, and a novel and feasible metal valence state modulation strategy is proposed to develop high-efficiency MAMs.

Understanding the Behaviors of Plasmon-Induced Hot Carriers and Their Applications in Photocatalysis.

Photocatalysis driven by plasmon-induced hot carriers has been gaining increasing attention. Recent studies have demonstrated that plasmon-induced hot carriers can directly participate in photocatalytic reactions, leading to great enhancement in solar energy conversion efficiency, by improving the catalytic activity or changing selectivity. Nevertheless, the utilization efficiency of hot carriers remains unsatisfactory. Therefore, how to correctly understand the generation and transfer process of hot carriers, as well as accurately differentiate between the possible mechanisms, have become a key point of attention. In this review, we overview the fundamental processes and mechanisms underlying hot carrier generation and transport, followed by highlighting the importance of hot carrier monitoring methods and related photocatalytic reactions. Furthermore, possible strategies for the further characterization of plasmon-induced hot carriers and boosting their utilization efficiency have been proposed. We hope that a comprehensive understanding of the fundamental behaviors of hot carriers can aid in designing more efficient photocatalysts for plasmon-induced photocatalytic reactions.

Tailoring Fluorescence-Phosphorescence Emission with a Single Nanocavity.

Realizing the dual emission of fluorescence-phosphorescence in a single system is an extremely important topic in the fields of biological imaging, sensing, and information encryption. However, the phosphorescence process is usually in an inherently "dark state" at room temperature due to the involvement of spin-forbidden transition and the rapid non-radiative decay rate of the triplet state. In this work, we achieved luminescent harvesting of the dark phosphorescence processes by coupling singlet-triplet molecular emitters with a rationally designed plasmonic cavity. The achieved Purcell enhancement effect of over 1000-fold allows for overcoming the triplet forbidden transitions, enabling radiation enhancement with selectable emission wavelengths. Spectral results and theoretical simulations indicate that the fluorescence-phosphorescence peak position can be intelligently tailored in a broad range of wavelengths, from visible to near-infrared. Our study sheds new light on plasmonic tailoring of molecular emission behavior, which is crucial for advancing research on plasmon-tailored fluorescence-phosphorescence spectroscopy in optoelectronics and biomedicine.

Direct S-H Evidence Revealing the Photo-electrocatalytic Hydrogen Evolution Reaction Mechanism on CdS Using Surface-Enhanced Raman Spectroscopy.

Photoelectrocatalytic water splitting using metal sulfides is a promising method for green hydrogen production. However, in situ probing of the hydrogen evolution reaction (HER) on sulfides with excellent performance remains a challenge. Here, we construct Au@CdS core-shell nanoparticles to study the HER on CdS, a typical HER catalyst, by surface-enhanced Raman spectroscopy (SERS) using a "borrowing" strategy. We directly capture the spectroscopic evidence of S-H intermediate under HER condition, further verified by isotopic experiments. Moreover, the population of S-H intermediates is improved by injecting charge carriers through light illumination and the S-H bond is weakened by introducing Pt to form a Au@Pt@CdS structure to change the interfacial electronic structure, both of them resulting in significant HER performance improvement. These findings can deepen the understanding of the HER mechanism and offer strategies for designing of cost-effective HER catalyst with high performance.

In Situ Raman Probing of Hot-Electron Transfer at Gold-Graphene Interfaces with Atomic Layer Accuracy.

Plasmonic metals under photoexcitation can generate energetic hot electrons to directly induce chemical reactions. However, the capability and fundamental insights of the transportation of these hot electrons at plasmonic metal-2D material interfaces remain unclear. Herein, hot-electron transfer at Au-graphene interfaces has been in situ studied using surface-enhanced Raman spectroscopy (SERS) with atomic layer accuracy. Combining in situ SERS studies with density functional theory calculations, it is proved that hot electrons can be injected from plasmonic Au nanoparticles to graphene and directly penetrate graphene to trigger photocatalytic reactions. With increasing graphene layers, the transportation of hot electrons decays rapidly and would be completely blocked after five layers of graphene. Moreover, the transfer of hot electrons can be modulated by applying an external electric field, and the hot-electron transfer efficiency under electrochemical conditions is improved by over three times in the presence of a monolayer of graphene.

Gap-Mode Surface-Plasmon-Enhanced Photoluminescence and Photoresponse of MoS2.

2D materials hold great potential for designing novel electronic and optoelectronic devices. However, 2D material can only absorb limited incident light. As a representative 2D semiconductor, monolayer MoS2 can only absorb up to 10% of the incident light in the visible, which is not sufficient to achieve a high optical-to-electrical conversion efficiency. To overcome this shortcoming, a "gap-mode" plasmon-enhanced monolayer MoS2 fluorescent emitter and photodetector is designed by squeezing the light-field into Ag shell-isolated nanoparticles-Au film gap, where the confined electromagnetic field can interact with monolayer MoS2 . With this gap-mode plasmon-enhanced configuration, a 110-fold enhancement of photoluminescence intensity is achieved, exceeding values reached by other plasmon-enhanced MoS2 fluorescent emitters. In addition, a gap-mode plasmon-enhanced monolayer MoS2 photodetector with an 880% enhancement in photocurrent and a responsivity of 287.5 A W-1 is demonstrated, exceeding previously reported plasmon-enhanced monolayer MoS2 photodetectors.

In situ SERS study of surface plasmon resonance enhanced photocatalytic reactions using bifunctional Au@CdS core-shell nanocomposites.

Surface plasmon resonance (SPR) has been utilized in many fields, such as surface-enhanced Raman spectroscopy (SERS) and solar energy conversion. Here we developed an Au@CdS core-shell nanostructure, a bifunctional nanoparticle, used as an efficient catalyst for SPR enhanced photocatalytic degradation, and as a substrate for in situ SERS detection of methylene blue (MB) and p-nitrophenol (pNTP). With integration of an Au nanoparticle into a CdS shell, the degradation process was significantly accelerated under 500 nm long-pass (λ > 500 nm) visible light irradiation, which was caused by the injection of hot electrons. Moreover, a highly uniform, monolayer film of Au@CdS nanoparticles (NPs) has been prepared and used as both a SERS substrate and catalyst. The decomposition of MB molecules and nitrogen coupling reaction of pNTP were observed during the 638 nm laser illumination. We demonstrate that a plasmonic core-semiconductor shell nanocomposite can be a promising material for photocatalysis and in situ SERS study.

[Operation Performance of a Bioaugmented Membrane-aerated Biofilm Reactor Treating Atrazine Wastewater].

A hydrophobic SPG (shirasu porous glass) membrane-aerated biofilm reactor (MABR) with genetically engineered microorganism (GEM) biofilm formed on the SPG membrane surface was applied to treat atrazine wastewater. The contaminant removal performance and its influencing factors were investigated during the stable operation of this MABR. The results indicated that the oxygen supply capacity could be increased in the SPG membrane aeration when the membrane pore size and the aeration pressure increased, which could improve the performance of COD and atrazine removals. The maximum oxygen supply capacity of hydrophobic SPG membrane with pore size of 1.5 µm was estimated to be about 22.4 g·(m2·d)-1 at aeration pressure of 70 kPa. When aeration pressure was 70 kPa and hydraulic retention time (HRT) was 1.5 h, the average COD removal efficiency was 80.1% and the average organic loading rate removed was 1.86 kg·(m3·d)-1in the MABR with 1.5 µm hydrophobic SPG membrane. Under the same operating conditions, the average atrazine removal efficiency was 62.5% and the average atrazine loading rate removed was 0.18 kg·(m3·d)-1. The COD and atrazine removal efficiencies decreased significantly at further shortened HRT and increased influent organic loading rate. DO concentration showed more significant influence on atrazine removal. The simplex genetically engineered microorganism biofilm turned into complex microbial community gradually during MABR operation, but the GEM cells could still reside in the biofilm well. Therefore, the efficient atrazine removal by GEM bioaugmentation could be maintained.

[Characteristics of acid red 3R wastewater treatment by ozone microbubbles].

The application of microbubble technology for ozonation wastewater treatment could enhance ozone mass transfer, improve ozonation performance and increase ozone utilization efficiency. The ozone microbubbles were used to treat synthetic acid red 3R wastewater in the present study, and compared to ozone conventional bubbles. The ozone mass transfer and ozonation characteristics of acid red 3R were investigated when ozone microbubbles and ozone conventional bubbles were applied. The results confirmed the enhanced ozone mass transfer using microbubbles. The ozone mass transfer coefficient using microbubbles was 3.6 times higher than that using conventional bubbles under the same conditions. Simultaneously, the ozone decomposition coefficient using microbubbles was 6.2 times higher than that using conventional bubbles, which would be favorable for *OH generation. The ozonation rate and mineralization efficiency of acid red 3R could be improved significantly using ozone microbubbles. A TOC removal efficiency of 78.0% was achieved using ozone microbubbles, which was about 2 times higher than that using ozone conventional bubbles. The ozone utilization efficiency using microbubbles was much higher that using conventional bubbles during ozonation treatment of acid red 3R. The average ozone utilization efficiencies were 97.8% and 69.3% when microbubbles and conventional bubbles were used, respectively. The oxidative ability of ozone microbubbles could be increased by enhancing *OH generation, and as a result, the oxidative reaction of degradation intermediates was accelerated by ozone microbubbles. Especially, the mineralization ability of small organic acid intermediates using ozone microbubbles was about 1.6 times higher than that using ozone conventional bubbles.

[Atrazine wastewater treatment in a SPG membrane-aerated genetically engineered microorganism biofilm reactor].

Membrane-aerated biofilm reactor (MABR) represent a novel membrane-biological wastewater treatment technology. In addition, bioaugmented treatment using genetically engineered microorganism (GEM) biofilm in MABR is proposed to improve refractory pollutant removal. In the present study, a SPG membrane aerated-biofilm reactor (SPG-MABR) with GEM biofilm formed on the SPG membrane surface was applied to treat atrazine wastewater. The influences of air pressure, biofilm biomass and liquid velocity on the performance of the SPG-MABR were investigated. The variation of GEM biofilm during the SPG-MABR operation was observed. The results indicated that the increased air pressure could promote atrazine and COD removal as well as re-oxygenation by increasing oxygen permeability coefficient. A higher biofilm biomass could also enhance atrazine and COD removal, but simultaneously reduce the re-oxygenation rate because biofilm thickness and oxygen transfer resistance increased. When liquid velocity in the SPG-MABR was decreased under laminar flow condition, atrazine and COD removal was improved due to the facilitated contaminant diffusion from wastewater to biofilm. The atrazine removal efficiency reached to 98.6% in the SPG-MABR after 5d treatment at air pressure of 300 kPa, biofilm biomass of 25 g x m(-2) and liquid velocity of 0.05 m x s(-1). The microbial polymorphism of GEM biofilm was observed during the SPG-MABR operation. The surface of GEM biofilm was gradually covered by other microbial cells and the distribution of GEM cells reduced, but inside the GEM biofilm, the GEM cells were still dominant.

[Enhanced electro-catalytic oxidation of dye wastewater with FePMo12 adopted catalyst].

Electrochemical oxidation degradation of azo dyes has become a widely used method in recent years. Iron phosphomolybdate (FePMo12) was synthesized with molybdophosphoric acid and ferric salt. Morphology and microstructure of catalyst were chararerized by IR spectrometry and X-ray diffraction. The heteropolyanion showed a Keggin structure. Electrochemical oxidation of acid red 3R was investigated in the presence of FePMo12 supported on modified 4A molecular sieve (4A) as packing materials in the reactor. The results showed that the optimal technological conditions for decolorization of acid red 3R simulated wastewater were as follows: active component load 3% , electrolytic voltage 22 V, initial pH 4, air-flow 0.08 m3 h- ', electrode span 3.0 cm. Under the opñrrizd conditions, the decolorization efficiency, COD and TOC removal efficiencies reached 75.3% , 65.4% and 46.0% after 90 min, respectively. With the addition of NaCI to the dyes solution during electrolysis, the decolorization efficiency increased, while the effect of Na2SO4 on the degradation was negative. The efficiency of degradation and mineralization of the acid red 3R were estimated based on the absorbance measurements by UV-vis. It shows that the conjugated structure of dye was destroyed primarily.

[Enhanced electro-chemical oxidation of Acid Red 3R solution with phosphotungstic acid supported on gamma-Al2O3].

Supported phosphotungstic acid catalysts on gamma-Al2O3 (HPW/gamma-Al2O3) were prepared by solution impregnation and characterized by FTIR, XRD, TG-DTA and SEM. The heteropolyanion shows a Keggin structure. Electro-chemical oxidation of Acid Red 3R was investigated in the presence of HPW supported on gamma-Al2O3 as packing materials in the reactor. The results show that HPW/gamma-Al2O3 has a good catalytic activity for decolorization of Acid Red 3R. When HPW loading was 4.6%, pH value of Acid Red 3R was 3, the voltage was 25.0 V, air-flow was 0.04 m3 x h(-1), and electrode span was 3.0 cm, the decolorization efficiency of Acid Red 3R can reach 97.6%. The removal rate of color had still about 80% in this electro-chemical oxidation system, after HPW/gamma-Al2O3 was used for 10 times, but active component loss existed. The interim product was analyzed by means of Vis-UV absorption spectrum. It shows that the conjugated structure of dye is destroyed primarily.

[Biocatalyst of redox mediators on the denitrification by Paracoccus versutus strain GW1].

The quinone respiration process of Paracoccus versutus strain GW1 was characterized and the effects of the four redox mediators on the denitrification process were studied. The experiment results suggested that quinones were utilized by Paracoccus versutus strain GW1 as electron acceptors in the respiratory chain and reduced to hydroquinone. Batch experiments were carried out to investigate the biocatalyst effect of redox mediators as catalyst on the denitrification process at 35 degrees C. All four redox mediators tested were able to enhance the nitrate removal efficiency and the denitrification efficiency by 1.14-1.63 fold and 1.12-2.02 fold, respectively. The accelerating effect from high to low was AQDS > 1,5-AQDS > AQS > alpha-AQS. In the presence of redox mediators, the stabilized ORP values in the nitrate decomposition process were reduced by 33-75 mV. The pH variations in denitrification with redox mediators showed similar tendency to that of the conventional nitrate removal process. In the concentration range of 0-0.32 mmol x L(-1), AQDS had the best accelerating effect and a linear correlation was found for the denitrification rate K and the AQDS concentration cAQDS. This study indicated that the application of redox mediators significantly improved the denitrification process by enhancing the decomposition rate.

[Catalyst effect and the structure-activity characteristics of redox mediators on the reactive brilliant red K-2BP decolorization].

Four selected quinone redox mediators with similar structure were conducted to accelerate reactive brilliant red K-2BP decolorization, and the accelerating structure-activity of redox mediators on the decolorization was also studied. Batch experiments were carried out to determine the catalyst effect on the decolorization of reactive brilliant red K-2BP with temperature of 35 degrees C and under anaerobic conditions. The experiment results suggested that (1) four similar chemical structure redox mediators [1, 4, 5, 8-Tetrachloroanthraquinone (1,4,5,8-AQ), Anthraquinone (AQ), 1,8-Dichloroanthraquinone (1,8-AQ), 1,5-Dichloroanthraquinone (1,5-AQ)], all accelerated the decolorization rate of reactive brilliant red K-2BP and the reaction rate was enhanced 1.4-3 times; (2) the accelerating order was 1,8-AQ >1 ,5-AQ > AQ >1,4,5,8-AQ at the quinone mediator concentration of 4 mmol x L(-1) and reactive brilliant red K-2BP concentration of 300 mg x L(-1); (3) under the reactive brilliant red K-2BP concentration of 300 mg x L(-1), 1,8-AQ had best accelerating effect, and the relationship between decoloring rate constants and 1,8-AQ concentration; (4) and the mediator acclerating effects also related to substituent positioning effects and conjugated effects. The structure-activity mathematical model of redox mediators was put forward, which could improve water-insoluble redox mediators catalytic strengthening theory system.

[Analysis of methanogenic community of anaerobic granular sludge based on mcrA gene].

The methanogenic community in anaerobic granular sludge from a full-scale UASB treating avernectin wastewater was analyzed based on mcrA gene, compared to 16S rRNA gene. The results indicated that the diversity indices of methanogenic community, including Shannon diversity index, Margalef richness index and Berger-Parker dominance index, were no difference between mcrA gene-based and 16S rRNA gene-based PCR products analysis by DGGE, although their DGGE band patterns were different, implying that the diversity analysis of methanogenic community based on mcrA genes was consistent with 16S rRNA gene. The phylogenetic analysis of dominant methanogenic populations based on these two target genes also showed resemble and Methanobacteriales and Methanosarcinales were determined to be the main orders of methanogenic populations in anaerobic granular sludge. On the other hand, the difference in phylogenetic analysis suggested simultaneously some group-specific of the two target genes. The hybridization of methanogenic community in FISH analysis based on two target genes was almost identical except a little different hybridization areas. The average relative abundance of methanogenic community was 24.25% +/- 6. 47% detected by FISH based on mcrA gene, lower than that based on 16S rRNA gene (33.42% +/- 2.34%). Then it could be concluded that the analysis of methanogenic community based on mcrA gene and 16S rRNA gene exhibited high resemblance and mcrA gene could used to be target gene for methanogenic community, as an alternative of 16S rRNA gene.

[Bioaugmented treatment of atrazine by genetically engineered microorganism in different bioreactors].

Removal of atrazine was investigated when genetically engineered microorganism (GEM) was inoculated into membrane bioreactor (MBR) and hybrid bioreactor for bioaugmentation. The performances of atrazine removal in two bioreactors were explored. The variations of GEM density and atzA gene abundance in two bioreactors were also determined. The results indicated that removal activities of COD and ammonia nitrogen were inhibited a little by atrazine and recovered after bioaugmentation by inoculated GEM. The better removal performance of COD and ammonia nitrogen was obtained in MBR. The biological removal efficiency of atrazine was improved significantly when bioaugmented treatment by GEM was applied. The atrazine removal increased gradually and the average removal rates reached up to 38.94% in MBR and 29.36% in hybrid bioreactor in the later running period. After inoculated, GEM densities in two bioreactors decreased rapidly and then tended to be constant. The stable GEM densities in MBR, suspended sludge and adherent biofilm of hybrid bioreactor were 5 x 10(3) CFU/mL, 1.1 x 10(3) CFU/mL and 0.4 x 10(3) CFU/mL, respectively. Fluorescence in situ hybridization (FISH) was used to detect azA gene in two bioreactors and the result indicated that the average relative abundances of atzA gene decreased initially and increased subsequently. The largest average relative abundance of atzA gene was obtained in MBR. The average relative abundance of atzA gene in adherent biofilm is larger than that in suspended sludge in the hybrid bioreactor. The horizontal transfer of atzA gene was the possible important reason responsible for high gene abundance.

[Analysis of methanogenic community of anaerobic granular sludge in a full-scale UASB treating avermectin wastewater].

Methanogens is considered to be important functional microbial population in anaerobic granular sludge. Fluorescence in situ hybridization was used to analyze methanogens of anaerobic granular sludge in a full-scale UASB treating avermectin wastewater. The results indicated that the distribution forms of methanogens, Methanobacteriales and Methanosarcinales were identical on the surface and inner face of granular sludge samples in different formation stages (with different diameters) , although the relative abundances of these methanogens were different. The relative abundances of methanogens on the inner face were larger than these on the surface of granular sludge samples. The relative abundances of Methanobacteriales were larger than these of Methanosarcinales. The relative abundances of methanogens in all granular sludge samples ranged from (25.50 +/- 8.63)% to (48.67 +/- 8.87)%. The maximum relative abundances of methanogens were obtained in mature granular sludge with diameter of 1.0-2.0 mm, (47.08 +/- 8.26)% on the surface and (48.67 +/- 8.87)% on the inner face, respectively. The avermectin residue in wastewater showed possible inhibition effect on methanogens. The maximum specific methanogenic activities of granular sludge samples ranged from 1.311 to 1.562 g/(g x d), varying as same as COD removal ratios and relative abundances of methanogens, implying the strong correlation of methanogens with bioactivity of granular sludge.

Effects of Sandalwood on pharmacokinetics of gallic acid and protocatechuic acid in Choerospondiatis fruit / 第二军医大学学报

Objective: To establish a HPLC method for in vivo determination of gallic acid (GA) and protocatechuic acid (PA) in rat plasma, and to study the effect of Sandalwood on the pharmacokinetics of GA and PA. Methods: SD rats were given the water extracts of Choerospondiatis fruit or Choerospondiatis fruit and Sandalwood. The pharmacokinetic parameters of GA and PA were calculated by DAS2. 0 software at different time points after an oral ration of the above extracts. Results: The pharmacokinetic parameters after oral administration of Choerospondiatis fruit extract were as follows: GA: Cmax: (0.112±0.008) mg·L-1, CL/F: (0.132±0.016) L·min-1·kg-1, t1/2β: (69.3±0) min, Tmax: (45.0±0) min; PA: Cmax: (0.550±0.028) mg·L-1, Tmax: (52.0±0) min, t1/2β, (60.7±1.1) min; CL/F: (0.078±0.011) L·min-1·kg-1. The pharmacokinetic parameters after oral ration of Choerospondiatis fruit-Sandalwood extract were as follows: GA: Cmax: (0.187±0.010) mg·L-1, CL/F: (0.094±0.017) L·min-1·kg-1, t1/2β: (69.3±3.3) min, Tmax: (30.0±0) min; PA: Cmax: (1.080±0.066) mg·L-1, Tmax: (45.0±0) min, t1/2β: (69.3±0.2) min, CL/F: (0.011±0.001) L·min-1·kg-1. Conclusion: Oral ration of Choerospondiatis fruit-Sandalwood extract results in earlier plasma peaks of PA and GA, lower clearance rate, and longer half life, indicating Sandalwood can promote the absorption of phenolic compounds in Choerospondiatis fruit.

In vitro drug release behavior from a novel thermosensitive composite hydrogel based on Pluronic f127 and poly(ethylene glycol)-poly(epsilon-caprolactone)-poly(ethylene glycol) copolymer.

BACKGROUND: Most conventional methods for delivering chemotherapeutic agents fail to achieve therapeutic concentrations of drugs, despite reaching toxic systemic levels. Novel controlled drug delivery systems are designed to deliver drugs at predetermined rates for predefined periods at the target organ and overcome the shortcomings of conventional drug formulations therefore could diminish the side effects and improve the life quality of the patients. Thus, a suitable controlled drug delivery system is extremely important for chemotherapy. RESULTS: A novel biodegradable thermosensitive composite hydrogel, based on poly(ethylene glycol)-poly(epsilon-caprolactone)-poly(ethylene glycol) (PEG-PCL-PEG, PECE) and Pluronic F127 copolymer, was successfully prepared in this work, which underwent thermosensitive sol-gel-sol transition. And it was flowing sol at ambient temperature but became non-flowing gel at body temperature. By varying the composition, sol-gel-sol transition and in vitro drug release behavior of the composite hydrogel could be adjusted. Cytotoxicity of the composite hydrogel was conducted by cell viability assay using human HEK293 cells. The 293 cell viability of composite hydrogel copolymers were yet higher than 71.4%, even when the input copolymers were 500 microg per well. Vitamin B12 (VB12), honokiol (HK), and bovine serum albumin (BSA) were used as model drugs to investigate the in vitro release behavior of hydrophilic small molecular drug, hydrophobic small molecular drug, and protein drug from the composite hydrogel respectively. All the above-mentioned drugs in this work could be released slowly from composite hydrogel in an extended period. Chemical composition of composite hydrogel, initial drug loading, and hydrogel concentration substantially affected the drug release behavior. The higher Pluronic F127 content, lower initial drug loading amount, or lower hydrogel concentration resulted in higher cumulative release rate. CONCLUSION: The results showed that composite hydrogel prepared in this paper were biocompatible with low cell cytotoxicity, and the drugs in this work could be released slowly from composite hydrogel in an extended period, which suggested that the composite hydrogel might have great potential applications in biomedical fields.

[Leakage and survival of genetically engineered microorganism in the environment applied for wastewater bioaugmentation treatment].

Genetically engineered microorganism (GEM) leaking from bioreactors to natural environment will lead to potential ecological risk when applied for wastewater bioaugmentation treatment. An atrazine-degrading GEM was used in a conventional activated sludge bioreactor (CAS) and a membrane bioreactor (MBR) to investigate leaking density of GEM. in the effluent. Survival of GEM in the simulated natural environments after leakage was also explored. The results showed that the maximum leakage happened at the initial time of GEM inoculation. When inoculating density was 10(10) CFU/mL, the maximum leaking density from CAS was close to inoculating density as well as the maximum leaking density from MBR was only 10(2) CFU/mL. Leaking density was the key factor influencing GEM survival in the simulated environments. When leaking density from CAS reached to 10(10) CFU/mL, GEM with high density would survive in the simulated water and soil environments for a long time (more than 30 d), which would lead to high potential ecological risk. On the contrary, when leaking density from MBR was 10(2) CFU/mL, GEM would disappear quickly in the simulated environments, which meant low potential ecological risk. Environmental conditions also affected GEM survival. Increasing water content and organic compounds content of soil as well as creating environmental selective pressure (adding atrazine) were profitable for GEM survival.