Synergistic effects of peroxydisulfate on UV/O_(3) process for tetracycline degradation:Mechanism and pathways

Tetracycline(TC)as a typical emerging pollutant is becoming a serious threat to the environment and human health.A combined advanced oxidation technology of UV/Ozone(O_(3))/peroxydisulfate(PDS)process was developed to explore an efficient and economic treatment process of TC in wastewater.Furthermore,the reactive sites and transformation pathways of TC were explored and the toxicity of the intermediates was quantified with a quantitative structure-activity relationship(QSAR)assessment.The degradation performance of TC was substantially enhanced in UV/O_(3)/PDS process with a kobsof 0.0949 min-1,which was 2.3 times higher than UV/O_(3)and 3.2 times than sole UV.The results demonstrated that there was a superior synergistic effect of PDS on UV/O_(3)processes for the degradation of TC.Electron paramagnetic resonance(EPR)analysis and quenching experiments show that·OH,SO_(4)·-,O_(2)·-and1O_(2)all contributed to TC degradation in the UV/O_(3)/PDS process and exhibited a synergistic effect,which inhibited the generation of harmful products.In addition,the UV/O_(3)/PDS system can effectively degrade TC in a wide range of substrate concentrations and pH,and also showed excellent adaptability to various concentrations of anions(Cl-and HCO_(3)-).This study proves the feasibility of UV/O_(3)/PDS process for treating TC contaminated wastewater with complicated water matrix.

Hydrophilic/underwater superoleophobic graphene oxide membrane intercalated by TiO2 nanotubes for oil/water separation

Membrane technology for oil/water separation has received increasing attention in recent years. In this study, the hydrophilic/underwater superoleophobic membrane with enhanced water permeability and antifouling ability were fabricated by synergistically assembling graphene oxide （GO） nanosheets and titanium dioxide （TiO2） nanotubes for oil/water separation. GO/TiO2 membrane exhibits hydrophilic and underwater superoleophobic properties with water contact angle of 62° and under water oil contact angle of 162.8°. GO/TiO2 membrane shows greater water permeability with the water flux up to 531 L/ （m^2·h·bar）, which was more than 5 times that of the pristine GO membrane. Moreover, GO/TiO2 membrane had excellent oil/water separation efficiency and anti-oil-fouling capability, as oil residual in filtrate after separation was below 5 mg/L and flux recovery ratios were over 80%.The results indicate that the intercalation of TiO2 nanotubes into adjacent GO nanosheets enlarged the channel structure and modified surface topography of the obtained GO/TiO2 membranes, which improved the hydrophilicity, permeability and anti-oil-fouling ability of the membranes, enlightening the great prospects of GO/TiO2 membrane in oil-water treatment.

Albumin-based Theranostic Nanosystem for Drug Controlled Release and Magnetic Resonance Imaging Guided Therapy

Chemotherapy is still a kind of important strategy for cancer treatment,but lacking effective delivery system limits the therapeutic outcome.Owing to the excellent biocompatibility,albumin has been employed as drug vehicle;however,it has to face complicated synthesis procedures and still needs an effective technology for the drug delivery evaluation.In this study,a facile method was utilized to prepare a protein-based theranostic system through the self-assembly of albumins with small molecules and drugs;furthermore,the paramagnetic divalent manganese ions were conjugated on the surface of the nanocomposite through a coordination bond and carried out the magnetic resonance imaging.This nanosystem with a stable structure exhibited about 80 nanometer size and 7.7[Mn]mM-1S-1 T1 relaxivity;moreover,the pH-sensitive drug releasing property and the imaging function empower it with theranostic cancer therapy.Moreover,the nanocomposites effectively entered into the cancer cells and showed superior antitumor ability;and these treated cells exhibited significant T1 signal.These results suggested that the albumin-based nanosystem is a novel chemotherapy drug delivery vehicle and a promising candidate for magnetic resonance imaging.

A hybrid membrane process for simultaneous thickening and digestion of waste activated sludge

A hybrid membrane process for simultaneous sludge thickening and digestion(MSTD)was studied.During one cycle(15 d)of operation under a hydraulic retention time of 1 d,the concentration of mixed liquor suspended solids(MLSS)continuously increased from about 4 g·L^(–1)to 34 g·L^(–1),and the mixed liquor volatile suspended solids(MLVSS)increased from about 3 g·L^(–1)to over 22 g·L^(–1).About 42%of the MLVSS and 39%of the MLSS reduction were achieved.The thickening and digestion effects in the MSTD were further analyzed based on a mass balance analysis.Test results showed that biopolymers and cations of biomass were gradually released to the bulk solution during the process.It was also found that the capillary suction time,colloidal chemical oxygen demand,soluble microbial products,viscosity,and MLSS had significant positive correlations with the membrane fouling rate,whereas extracellular polymeric substances,polysaccharides,and proteins extracted from biomass had negative impacts on membrane fouling.

Cisplatin and paclitaxel co-delivery nanosystem for ovarian cancer chemotherapy

We have designed and developed an effective drug delivery system using biocompatible polymer of poly(ethylene glycol)-polyaspartic acid(mPEG-PAsp)for co-loading the chemotherapy drugs paclitaxel(PTX)and cisplatin(CP)in one nano-vehicle.This study aimed to improve the anti-cancer effi-cacy of combinations of chemotherapy drugs and reduce their side effects.mPEG-PAsp-(PTX/Pt)nano-micelles disperse well in aqueous solution and have a narrow size distribution(37.863.2 nm)in dynamic light scattering(DLS).Drug release profiles found that CP released at pH 5.5 was signifi-cantly faster than that at pH 7.4.MPEG-PAsp-(PTX/Pt)nano-micelles displayed a significantly higher tumor inhibitory effect than mPEG-PAsp-PTX nano-micelles when the polymer concentrations reached 50 lg/mL.Our data indicated that polymer micelles of mPEG-PAsp loaded with the combined drug exert synergistic anti-tumor efficacy on SKOV3 ovarian cells via different action mechanisms.Results from our studies suggested that mPEG-PAsp-(PTX/Pt)nano-micelles are promising alternatives for carrying and improving the delivery of therapeutic drugs with different water solubilities.