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F-box/WD repeat-containing protein 7 (FBXW7) is the substrate recognition component of SCF (SKP1-CUL1-F-box protein) E3 ubiquitin-protein ligase complex which mediates the ubiquitination and subsequent proteasomal degradation of target proteins. FBXW7 recognizes and binds phosphor-degrons within target proteins and capture them to SCF complex for ubiquitination. Know FBXW7 substrates include cyclin-E, DISC1, JUN, MYC, NFE2L1, NOTCH2, MCL1, RICTOR, and NOTCH1 released notch intracellular domain (NICD). FBXW7 is frequently mutated in cancer, results in loss of substrate recognition and binding. R465C is a one of the major FBXW7 mutations and is found in over 70,000 cancer patients worldwide. From a high-throughput screen, we discovered compounds that selectively bind to FBXW7 R465C mutant. PROTACs against various protein targets have been made with these mutant specific ligands. Some of these PROTACs could induce targeted protein degradation in cells carrying FBXW7 R465C mutant but not wild-type FBXW7. Targeted protein degradation with these PROTACs could represent a novel therapeutic approach against FBXW7 R465C mutant cancer. Citation Format: Zhaofu Wang, Lynette Zhang, Zhen Chang, Mengxi Zhao, Guobin Li, Fang Qin, Shichao Ma, Yunfeng Li, Zhongguo Zhang, Xinghao Wang, Ying Kong, Shidi Lou, Sheng Chen, Lanzhen Liu, Shuaijie Xu, Hailong Zhang. Discovery of cancer-specific E3 ligase ligands for targeted protein degradation. [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 4962.

A hybrid process of enhanced coagulation at a high dosage of polyaluminum chloride and flat-sheet cross-flow ultrafiltration was used for the advanced treatment of the effluent from a biological treatment process of deinking wastewater in a paper mill. The experimental results obtained by a small-scale continuous laboratory experimental device showed that the absorption resistance was significantly lower than the membrane intrinsic resistance, the concentration polarization resistance, the pore blocking resistance, and the cake layer resistance and so it can be ignored. With increasing polyaluminum chloride dosage from 0 to 2,000 mgL-1, the total membrane filtration resistance decreased and the membrane flux increased, but the concentration polarization resistance increased. With the increase in cross flow velocity, the total membrane filtration resistance, the pore blocking resistance, the layer resistance, and the concentration polarization resistance all decreased, and consequently, the membrane flux increased. With regard to the concentration polarization resistance, the cross flow velocity had a more significant effect than the trans-membrane pressure. But the trans-membrane pressure had a more significant effect on the layer resistance, the pore blocking resistance, and the total membrane filtration resistance than the cross flow velocity. The filtration resistance at the polyaluminium chloride dosage of the pore blocking resistance > the layer resistance > the concentration polarization resistance> the absorption resistance. But it was the membrane intrinsic resistance > the concentration polarization resistance > the pore blocking resistance > the layer resistance > the absorption resistance at the dosage of ≥1,000 mgL-1. The results are helpful for the membrane fouling control and can promote the application of flat-sheet cross-flow membrane process, resultantly improving the reclaim and reuse of deinking wastewater, and reducing the emission of contaminants in deinking wastewater.

To minimize the effect of the internal concentration polarization (ICP) in the substrates of the forward osmosis (FO) membranes, higher overall porosity and interconnected pore network was engineered into the substrates by erosion of the three-dimensional layered double hydroxides (LDHs) with “sand rose” morphology. As expected, the substrates showed high porosity and macropore structure in the pore-wall after erosion of the LDH nanoparticles by HCl washing, which potentially promoted connectivity of the finger-like pores in the substrates. Therefore, the promising water flux for as-obtained FO membrane prepared from the typical interfacial polymerization was observed. The obtained TFN7.5-HCl membranes displayed the highest water flux up to 47.2 L m−2 h−1 at PRO mode (1 M NaCl as draw solution and DI-water as feed solution) and the water permeability coefficient reaching 7.29 L m−2 h−1 bar−1 at RO mode (DI-water as feed solution, ΔP = 5 bar). These values were much higher than that of the commercial FO membranes. Counterintuitively, the obtained TFN7.5-HCl membrane disentangled successfully the dilemma of permeability–selectivity, e.g. improved selectivity between water and NaCl was achieved. Thus, it is believed that the designation strategy provides a simple and promising method to fabricate the enabled high-performance FO membranes.

Separation and treatment of human urine from domestic wastewater have been recognized as a sustainable alternative to conventional urban sanitation system, but the unique water quality of source-separated urine, such as high nutrient, insufficient alkalinity and low COD/nitrogen ratio, poses challenges to the biological nitrogen removal process. It was hypothesized that a physicochemical pre-treatment should be adopted to not only reduce nitrogen load but adjust water quality suitable for biological treatment. In this study, a vacuum thermal stripping process coupled to acid absorption was used as a pre-treatment to recover ammonia from hydrolyzed urine in the form of ammonium sulphate. The maximal ammonia mass transfer coefficient of 17.6 mm/h was obtained under 60 °C and 21.3 kPa 80% of the nitrogen in hydrolyzed urine was recovered in 3 h batch stripping experiments without pH adjustment, corresponding to a nitrogen recovery loading rate of 36 kg N/m3⋅d. The majority of organic matters were retained in urine solutions, thus COD/N and alkalinity/NH4+ N ratios were elevated to 4.75 and 4.37, respectively. Phosphorus recovery could be simultaneously obtained in stripping process by adding MgCl2. The remaining nitrogen was effectively removed via short-cut nitrification and denitrification in an anoxic/oxic membrane bioreactor. More than 95% of overall nutrient recovery/removal from urine was achieved with a minimal consumption of external resources. The economic assessment of the technique showed that the recovery/removal of nutrients from 1 m3 of urine can make a profit of € 0.26.

In this work, both Electrocoagulation (EC) and Fered-Fenton (FF) technologies were used to treat reverse osmosis concentrates (ROC) from petrochemical production. The toxicity reduction capacity and mechanism were comparatively assessed during these two treatments. The results showed that FF exhibited higher capacity to reduce toxicity than EC in the 30 min treatment, which could be attributed to the removal of organic pollutants and heavy metals. The results showed that the ROC contained organics with molecular weight of 1200 g mol−1 and 220 g mol−1, which mainly consisted of the soluble microbial by-product-like and humic acid-like substances. The removal of these organics directly led to the noticeable toxicity reduction. Alkanes, haloalkanes, ketones, PAHs, and other four organic pollutants were the dominant species in the ROC, and the removal of small molecular weight organic pollutants played an essential role in reducing toxicity. FF exhibited stronger capacity to remove PAHs, BTEXS and haloalkanes, and the removal efficiencies for the PAHs were in the following order: 5-ring > 4-ring > 3-ring > 2-ring. The promotion of heavy metals removal appeared to be favorable for decreasing toxicity in ROC. This study illustrated the mechanism of the toxicity reduction and the characteristics of pollutants removal during FF and EC treatments, and provided valuable guidance for petrochemical manufacturing to the toxicity reduction and operation of wastewater treatment facilities.

Source separation and treatment of human urine have been recognized as a resource-efficient alternative to conventional urban drainage, not only reducing nutrient loads on municipal wastewater treatment plants, but recovering valuable resources from waste streams. In this work, on-site phosphorus (P) recovery from real urine was carried out by using the brine from a reverse osmosis process as the flush water for urine-diverting toilets and a P precipitant, while nitrogen (N) was removed via short-cut nitrification-denitrification (SCND) in a membrane bioreactor (MBR). More than 90% of P was recovered by mixing the urine with reverse osmosis brine (1:1, v/v) under the condition of pH > 9.0. The recovered precipitates contained 10–15% of P and can potentially be reused for phosphate fertilizer production. Stable SCND was achieved in a MBR, and 45% of N was removed with the organic compounds in urine as the electron donor for denitrification. Methanol addition significantly elevated denitrification, which in turn replenished the alkalinity required for nitrification. More than 99% of P, 90% of organics and 90% of N were removed in the combined precipitation and MBR process. Nitrosomonas was observed to be the predominant ammonium-oxidizing bacteria, while nitrite-oxidizing bacteria (NOB) were absent in the microbial communities as revealed by fluorescence in situ hybridization and pyrosequencing technique. High concentrations of free ammonia and nitrite acids, as well as low dissolved oxygen, are the prevailing factors to inhibit the growth of NOB, which allows for stable operation of SCND in the MBR.

Polycyclic aromatic hydrocarbons (PAHs) are an important class of water pollutants because of their known ecological and human toxicity. Electrocoagulation (EC) is a promising technology for mitigating industrial wastewater pollution, but the removal and transformation of PAHs during EC treatment has not yet been understood. Therefore, a paper-making wastewater effluent (PMWW) was employed in this study to investigate the relationship between PAHs’ removal and transformation during EC treatment. The results show that 86% of PAHs were effectively removed not only by the electro-oxidation reactions, but also by adsorption onto Fe hydroxide flocs. The removal and transformation of PAHs were related to the number of rings in their structures. Some PAHs composed of two aromatic rings (e.g., naphthaline and dimethylnaphthalene) were produced from humic acid-like and fulvic acid-like organics in PMWW, while PAHs with three to four rings were degraded, thus being removed efficiently. Therefore, PAH transformation during EC treatment exerted double-sided effects on the removal of PAHs; the net effect appeared to be positive. Overall, this study revealed the existence and importance of PAH transformation during EC treatment and provided useful guidance for pulp and paper mills to improve the design and operation of wastewater treatment facilities.

In this study, biologically treated, paper-making wastewater (PMWW) containing toxic polycyclic aromatic hydrocarbons (PAHs) was employed as the feedwater to investigate the effectiveness and mechanisms of integrated electrocoagulation (EC) and membrane filtration for the control of PAH pollution incurred by industrial wastewater discharge. The results showed that the integrated treatment was capable of removing more than 90% of polyaromatic hydrocarbon compounds (PAHs) and total organic carbon (TOC) from the wastewater. Specifically, the EC pretreatment contributed to approximately 40% TOC removal and 75% PAH removal via the combined effects of coagulation and oxidation, thereby significantly lowering the contaminant loading of the LPRO treatment. Among the PAHs removed by the EC, 3-ring and 4-ring compounds, including acenaphthene, anthracene, phenanthrene, fluorene and fluoranthene were effectively removed. However, EC-induced degradation of humic-like and fulvic-like substances produced 2-ring PAH compounds, including naphthalene and dimethylnaphthalene, that did not exist in the PMWW. Very importantly, the LPRO treatment efficiently rejected residual PAH compounds in the EC effluent, including those formed by EC treatment, through the solution-diffusion process. Overall, the quality of the final effluent meets the requirements for industrial water reuse; this exhibits the potential value of EC–LPRO for PAH pollution control.

Phosphorus (P) recovery from waste streams has recently been recognized as a key step in the sustainable supply of this indispensable and non-renewable resource. The feasibility of using brine from a reverse osmosis (RO) membrane unit treating cooling water as a precipitant for P recovery from source separated urine was evaluated in the present study. P removal efficiency, process parameters and precipitate properties were investigated in batch and continuous flow experiments. More than 90% of P removal was obtained from both undiluted fresh and hydrolyzed urines by mixing with RO brine (1:1, v/v) at a pH over 9.0. Around 2.58 and 1.24 Kg of precipitates could be recovered from 1 m3 hydrolyzed and fresh urine, respectively, and the precipitated solids contain 8.1–19.0% of P, 10.3–15.2% of Ca, 3.7–5.0% of Mg and 0.1–3.5% of ammonium nitrogen. Satisfactory P removal performance was also achieved in a continuous flow precipitation reactor with a hydraulic retention time of 3–6 h. RO brine could be considered as urinal and toilet flush water despite of a marginally higher precipitation tendency than tap water. This study provides a widely available, low - cost and efficient precipitant for P recovery in urban areas, which will make P recovery from urine more economically attractive.

Phosphorus (P) recovery from wastewater has been recognized as a critical technology for solving the sustainable supply of this indispensable and non - renewable natural resource. In this study, the cost - free magnesium and calcium sources of using the cooling water system effluent (CWSE) in two thermal power plants were proposed (Z - CWSE and G - CWSE) and the P recovery performance from source - separated urine was investigated. About 90% P recovery efficiency was achieved from the hydrolyzed urine when Z - CWSE and G - CWSE were added at the Ca: Mg: P molar ratios of 3.1 : 4.0: 1 and 3.6 : 3.4: 1, respectively. More than 95% P recovery performance was obtained from the fresh urine as the initial pH of the CWSE - FU mixtures was adjusted to over 9.5 and 10.0, respectively. The precipitates obtained contain 10.84–17.04% Ca, 6.22–9.58% P, 0.75–3.76% Mg and 0.13–0.23% N. XRD analysis confirmed the presence of struvite in the precipitates. The reuse of precipitates is secure due to extremely low contents of heavy metals. The feasibility of using CWSEs as the flushing water in urinals and toilets was assessed. Besides, we proposed CWSEs could be invoked as precipitants in various wastewaters as long as it contains considerable phosphate, e.g. P concentration more than 100 mg/L and 50 mg/L for Z - CWSE and G - CWSE, respectively.

This paper studied a series of main and objective factors that affect production safety in the process of mining for metal ore, analyzed all kinds of safety factors and their sets, levels and weights, established the corresponding expert system, and the fuzzy mathematics model of the safety evaluation of the metal mining process was established, and it is applied to the safety evaluation of the Maoping lead zinc ore in Yunnan province.The practice shows that the model is a feasible, objective, fair, comprehensive and quantifiable safety assessment method, which realizes the quantitative assessment of metal ore production process and has good application value for the safety assessment of metal ore mining.

Coagulation has been the most successful pretreatment for the mitigation of membrane fouling, the improvement of permeate quality, and the extension of membrane service life. Membrane coagulation reactor (MCR), which is a coupled coagulation and membrane filtration process, is a promising technology for surface water purification. In order to decrease footprint, promote flocculation efficiency, and mitigate efficiently membrane fouling, a submerged internal loop MCR with in-line coagulation, sludge thickening, and air sparging was developed. In the MCR, the internal loop flow induced by air lift through a flocculation region can cause a continuous flocculation of raw water and consequently avoid the accumulation of fine flocs prone to blocking membrane pores and forming a compact cake layer. Furthermore, the flocs with a large size and a fast settling velocity can consecutively settle into the sludge thickening region and then are discharged for controlling sludge concentration. The MCR with hollo...

It is of great concern to develop a high-efficient adsorbent for removing halomethanes, because they are harmful to human health. In this work, the activated carbon microspheres (ACMs) derived from spherical copolymer of vinylidene chloride and styrene were used to adsorb these hazardous pollutants from gases. The BET surface area of the ACM was 1104 m2/g and mostly dedicated by the micropores between 0.4 and 1.5 nm. The micropore dominating the nature of the ACM renders eminent adsorption capacity. The uniform scales on the surface and expedite passages inside the ACM offer excellent mass transfer performance during adsorption process. To assess the adsorption behavior of the ACM, dynamic adsorption tests were conducted at different temperatures, feed concentrations, and gas velocities. For comparison, a typical commercial activated carbon made from coconut shell was also tested under identical conditions. The results show that the ACM has large adsorption capacity, good adaptability and easy recyclability, which renders high potential and cost-effectiveness for commercial utilization.

Removal of natural organic matter (NOM) from drinking water by membrane technology is attracting increasing attention. However, the fouling of the membrane by NOM is one of the biggest obstacles restricting its widespread application. Therefore an anti-NOM fouling polyelectrolyte complex (PEC) membrane was obtained by creating a negatively charged multilayer on a polyacrylonitrile (PAN) supporting membrane using a layer-by-layer assembly method. To improve the stability of the PEC membrane, the electrostatically assembled (poly(ethyleneimine)/poly(sodium 4-styrenesulfonate))n/PAN membranes were crosslinked by glutaraldehyde. It was found that the zeta potential of the membrane surface decreased after chemical crosslinking, which further improved the electrostatic repulsion to NOM and thus improved the anti-NOM fouling property. Results of a 30 day nanofiltration operation showed the crosslinked membrane had good stability and gave a higher rejection of NOM; the permeance of the crosslinked membrane was double that of the uncrosslinked membrane.

Biologically treated leachate usually contains considerable amount of refractory organics and trace concentrations of xenobiotic pollutants. Removal of refractory organics from biologically treated landfill leachate by a novel microwave discharge electrodeless lamp (MDEL) assisted Fenton process was investigated in the present study in comparison to conventional Fenton and ultraviolet Fenton processes. Conventional Fenton and ultraviolet Fenton processes could substantially remove up to 70% of the refractory organics in a membrane bioreactor treated leachate. MDEL assisted Fenton process achieved excellent removal performance of the refractory components, and the effluent chemical oxygen demand concentration was lower than 100 mg L−1. Most organic matters were transformed into smaller compounds with molecular weights less than 1000 Da. Ten different polycyclic aromatic hydrocarbons were detected in the biologically treated leachate, most of which were effectively removed by MDEL-Fenton treatment. MDEL-Fenton process provides powerful capability in degradation of refractory and xenobiotic organic pollutants in landfill leachate and could be adopted as a single-stage polishing process for biologically treated landfill leachate to meet the stringent discharge limit.

Acrylonitrile (AN) wastewater is a heavily polluted and a likely hazardous liquid that is generated during the production of AN. Several chemical methods for the pretreatment of AN wastewater are available in laboratory scale. However, the harsh reaction conditions and high operational cost make these methods undesirable. Until now, four-effect evaporation is the only pretreatment method used for AN wastewater in industry despite its huge energy consumption and high cost. It is difficult to find an energy-saving pretreatment technique from the perspective of industrial application. In this study, a safe and low-cost coagulation technique was developed for the pretreatment of AN wastewater. Three types of inorganic coagulant and three types of polymer coagulant were investigated for the coagulation treatment of highly concentrated AN wastewater from petrochemical plants. The effects of coagulant type, dosage, and coagulation conditions on the pretreatment efficiency of AN wastewater were investigated. The results show that a combination of inorganic and polymer coagulants is effective for the pretreatment of AN wastewater.

Three new cardenolides (1–3) were isolated from the 90% ethanolic extract of the bark of a wild-type Calotropis gigantea. Their structures were determined by using NMR spectra and LC-MS analysis. Their inhibitory activities were evaluated against non-small cell lung carcinoma (A549) and human cervix epithelial adenocarcinoma (HeLa) cell lines. Compounds 1 and 3 exhibited strong inhibitory effect on two cancer cell lines.

Conventional jar tests and on-line size monitoring were used to investigate the effects of slow-mixing intensity and duration on residual turbidity and floc size during charge neutralization coagulation and sweep flocculation with polyaluminum chloride. The compensatory effect of slow-mixing on coagulation performance following inadequate or excessive rapid-mixing was also examined. It is found that slow-mixing intensity has a more marked positive effect on charge neutralization coagulation than on sweep flocculation. The optimal root-mean-square velocity gradient, G, for slow-mixing is 15 s−1 for both coagulation mechanisms, and charge neutralization coagulation requires a longer slow-mixing duration. The optimal slow-mixing duration, based on residual turbidity, is longer than the time to form the largest mean flocs. The optimal product of G and mixing duration, GT, for slow-mixing during charge neutralization coagulation (13500) are higher than that during sweep flocculation (4500) and both are less than the range of values recommended by the American Water Works Association (24000-84000). The optimal GT value under various slow-mixing conditions increases with G. Appropriate extension of slow-mixing duration during charge neutralization coagulation can improve coagulation performance after an inadequate or excessive rapid-mixing duration, but during sweep flocculation, appropriate shortening of slow-mixing duration after an excessive rapid-mixing or appropriate extension of slow-mixing duration after an inadequate rapid-mixing is favorable.

Bromate is a potential toxin that can be formed from bromide during the disinfection of drinking water by ozone. The performance of silver-loaded porous carbon spheres (SLPCSs) for removing the bromate precursor, bromide (Br−), was investigated under a range of conditions. The saturated SLPCS were then regenerated and tested to determine reusability. Porous carbon spheres (PCSs) were also prepared by carbonization of spherical poly(vinylidene chloride) and their ability to remove bromide compared with SLPCS. SLPCS were more efficient adsorbents than PCS because of the presence of silver and their adsorption capacity reached as high as 1.20 mg/g at 25 °C under the experimental conditions used. The removal of Br− by SLPCS was determined by batch and rapid small-scale column tests to assess the kinetic and dynamic adsorption behaviors. The equilibrium adsorption data fit well with the Langmuir isotherm and the Br− adsorption process followed a pseudo-second-order kinetic model. Both removal efficiency and adsorption capacity improved with increasing temperature. The feasible range of pH for Br− removal was between 4 and 7 and optimal performance was attained at pH 5. The presence of competitive species, such as Cl−, I−, NO 3 - , SO 4 2 - and humic acid, resulted in poor Br− adsorption, with their impact following the order: I− > SO 4 2 - > NO 3 - > Cl−. In the presence of competitive species, the impact of pH was minor, except for the I− anion. Regenerated SLPCS retained satisfactory performance.

The effect of thermal treatment on the formation and transformation of Al-13 and Al-30 species in highly concentrated hydrolytic polymeric At solutions (HPA) (0.2-1.0 mol L-1) were studied quantitatively using high-field Al-27 nuclear magnetic resonance (NMR) and time-developed Al-Ferron complex colorimetry. The results indicate that the metastable Al-13 species in HPA tends to polymerize and transform into Al-30 and other high polymers upon thermal treatment. The polymerization and transformation are speed up by heating at high temperature. Al-13 content in HPA decreases upon thermal treatment, and Al-30 content increases. Al-13 does not convert to Al-30 quantitatively due to its aggregation and acidic dissociation reactions. Al-13 species is a dominant nanosized Al species in freshly prepared HPA solutions, and its content reaches above 80.0% in HPA with Al-T = 0.2 mol L-1 and optimal hydrolysis ratios (B) (ca. 2.3-2.4). But the content of Al-30 becomes higher than that of Al-13 when the HPA solution is heated at 95 degrees C for more than 12 h. Al-30 becomes the dominant nanosized At species in HPA, and its content reaches 76.8% in sample with Al-T = 0.2 mol L-1 and B = 2.4. Although Al-30 is more stable than Al-13, it is also a metastable species during the process of At hydrolysis, polymerization and precipitation. The decomposition and polymerization of Al-30 are also speed up by increase the heating temperature. The optimal preparation temperature of Al-30 is ca. 95 degrees C. At species in HPA solutions transform into more stable and inert species through inter-species polymerization and intra-species structure rearrangement upon thermal treatment. So Al-b Contents decrease, and Al. contents increase. Al-30 cannot react with Ferron within 120 min, and it is classified as Al-c species in Al-Ferron analysis. The effect of thermal treatment on Al speciation in HPA solutions with different total At concentration and B value were also investigated. (c) 2006 Elsevier B.V. All rights reserved.

PU(Polyurethane) material is promising in pervaporation application. Polyether-based PU prepolymers were used to prepare a series of PU membranes. Then, the structure and properties of the above-prepared membrane materials were characterized by means of FTIR and swelling experiment. And the performance of pervaporation separation of phenol/water was studied. The result shows that The swelling degree is decreased by the addition of zeolite. Using solution with phenol (0.5wt %) in water. With feed temperature increased, there's an anti-trade-off phenomenon. At 80 °C, the flux is 319.95 kg·μm·m-2· h-1, and separation factor is 7.19.

Carbon nanotubes (CNTs), a novel kind of carbon, were first reported by Iijima in 1991 [1]. CNTs can be thought of as cylindrical hollow micro-crystals of graphite [2]. Because they have relatively large specific area, CNTs have attracted researchers interest as a new type of adsorbent and offer an attractive option for the removal of organic and inorganic contaminants from water. Li et al. found that acid-refluxed CNTs can be good adsorbents for Pb and Cd [3,4]. Peng et al. reported that CNTs can also be used to remove organic pollutants from water [5]. Because of their relatively large specific area, CNTs can also be used as supports for adsorption materials. Li et al. prepared amorphous Al2O3 supported on carbon nanotubes (Al2O3/CNTs) and found that it has a much higher adsorption capacity of fluoride than c-Al2O3 [6]. Our previous research has found that ceria nanoparticles supported on carbon nanotubes can be effective adsorbent for the removal of arsenate from water [7]. In this work, a novel kind of magnetic composites based on CNTs was prepared and the obtained composites show good adsorption capacity for Pb(II) and Cu(II) from aqueous solution. CNTs-iron oxide magnetic composites can be used to adsorb contaminants from aqueous effluents and after the adsorption is carried out, the adsorbent can be separated from the medium by a magnetic process. The preparation of carbon-iron oxides magnetic adsorbent based on activated carbon has been reported in the literature [8]. But magnetic adsorbent based on CNTs has not been reported and is the topic of the present study. CNTs were prepared by catalytic pyrolysis of the propylene-hydrogen (C3H6:H2 = 2:1) mixture at 750 C in a ceramic tube furnace using Ni particles as catalysts. The CNTs were then washed with deionized water and ground. The specific area of as-grown CNTs is 134.0 m g . For the preparation of CNTs-iron oxide magnetic composites, CNTs were first immersed in concentrated nitric acid and then hydrofluoric acid for 24 h each to dissolve the catalyst particles. Then they were oxidized by refluxing the as-prepared CNTs with 50% nitric acid at 140 C for 1 h. The magnetic composites were prepared from a suspension of 1.0 g oxidized CNTs in a 300 ml solution of 0.585 g FeCl3 AE 6H2O and 0.390 g FeSO4 AE 6H2O at 70 C under N2 atmosphere. NaOH solution (18.7 ml, 0.5 mol l ) was added dropwise to precipitate the iron oxides. After the addition of NaOH solution, the mixture was adjusted to pH 11.0 and stirred for 30 min. Then the mixture was aged at 70 C for 2 h and washed 3 times with deionized water. The obtained material were dried in an oven at 45 C and ground (particle size

Transition phenomena for the natural convection of a magnetic fluid in a square cavity was studied numerically for an externally imposed magnetic field. In the present study, particular attention was focused to verify heat transfer characteristics for non-gravity situation when the magnetic field was imposed. By applying magnetic fields the convection state many be largely affected improving heat transfer characteristics followed by various flow transitions in the non-gravity simulation. It was revealed that magnetic field could enhance the convection and consequently improves heat transfer characteristics, indicating that the magnetic field would be used as a substitute for the gravity in the zero-gravity situation of space.

By increasing particle concentration and C value (root-mean-square velocity gradient) to enhance flocculation, a novel vertical-flow settler was designed to increase sedimentation effectiveness, and to simultaneously improve operational stabilization. Due to the gradual decrease in upward flow-rate of raw water, a floes blanket would form and suspend in the middle section of the settler, not at the bottom as in a conventional clarifier. Enough large floes, resulted from flocculation or filtration, would continuously settle out of the floes blanket, and simultaneously, the floes in raw water or those forming above the blanket would ceaselessly enter the flocs blanket. As a result, the floes concentration in the blanket could keep a dynamic balance. The hydrodynamic shear in the blanket was improved by flow separation, which was induced by the abrupt change in flow channel. Due to the floes blanket and improved hydrodynamic shear, flocculation would be enhanced, which was helpful for removing fine particles in raw water. A comparative study showed that the novel vertical-flow settler had a much better performance in the removal of the particles in raw water than a conventional one, when they treated kaolin suspensions of different concentrations (500, 100 and 50 mg/L, respectively) coagulated by polyaluminum chloride(PACI) at the up-flow rates of I and 2 mm/s, respectively.

Polyaluminum coagulant with a content of 76.8% of Al30 (PACAl30) was prepared. Its coagulation behaviors were compared with high Al13 content polyaluminum coagulant (PACAl13) and AlCl3. The species stability was studied using Al-Ferron method and 27Al NMR. The coagulation performances were investigated by studying the rate of flocs development, the turbidity removal efficiency and charge neutralization capacity under fixed pH conditions and uncontrolled pH conditions. The effect of pH on coagulation was also studied. The results show that PACAl30 are stable for using as coagulant. PACAl30 causes less pH depression than PACAl13. The charge neutralization capacity of PACAl30 is slightly lower than that of PACAl13 at pH6.8 and higher at pH 6.5. PACAl30 achieves the most effective turbidity removal in these three coagulants. And it acts effectively within a much broader dosage range and a wider pH range when compared with PACAl13. PACAl30 achieves the highest turbidity removal due to its strong flocs formation capacity. The results verify that Al30 is another highly active coagulation/flocculation species for turbidity removal.

The effect of acidification and heat treatment of raw red mud (RM) and fly ash (FA) on the sorption of phosphate was studied in parallel experiments. The result shows that a higher efficiency of phosphate removal was acquired by the activated samples than by the raw ones. The sample prepared by using the RM stirred with 0.25 M HCl for 2h (RM0.25), as well as another sample prepared by heating the RM at 700 degrees C for 2h (RM700), registered the maximum removal of phosphate (99% removal of phosphate). This occurred when they were used in the phosphate sorption studies conducted at pH 7.0 and 25 degrees C with the initial PO(4)(3-) concentration of 155 mg P/l. The FA samples treated in the same way described above can achieve 7.0 and 8.2 mg P/l phosphate removal for FA0.25 and FA700 respectively, corresponding to 45.2% and 52.9% removal. The activated materials performed higher phosphate removal over broader pH range compared with the raw ones. The influences of various factors, such as initial pH and initial phosphate concentration on the sorption capacity were also studied in batch equilibration technique. Solution pH significantly influenced the sorption. Each sample achieved the maximal removal of phosphate at pH 7.0. The amount of phosphate removal increased with the solute concentration. The Freundlich and Langmuir models were used to simulate the sorption equilibrium. The results indicate that the Langmuir model has a better correlation with the experimental data than the Freundlich model.