Abstract:Five types of commonly used granular activated carbon （coconut shell pickling， coconut shell water washing， coal， fruit shell， wood activated carbon） were selected to study the adsorption isotherm and adsorption kinetics of 2，4，6-trichloroanisole （2，4，6-TCA ） and 2，4，6-tribromoanisole（2，4，6-TBA ）.Results show that all the used activated carbon can effectively adsorb halogenated anisole and the adsorption isotherms are well fitted to Freundlich model （R²>0.97）. The fruit shell activated carbon and coconut shell activated carbon performe better. Fruit shell activated carbon has the maximum adsorption capacity（K_F） for 2，4，6-TCA， while coconut shell pickling activated carbon possesses the maximum K_F for 2，4，6-TBA . The adsorption processes are consistent with the pseudo-second-order kinetics model （R²>0.97）. The adsorption rate of 2，4，6-TCA on coconut shell washing activated carbon is the fastest， and the adsorption rate of 2，4，6-TBA on pickled coconut shell activated carbon is the fastest. The adsorption mechanism and main influencing factors of coconut shell pickling activated carbon are studied. The results show that the internal diffusion is the main rate-limiting step， chemical adsorption is the main adsorption mechanism， and the concentration of initial substrate and dissolved organic matter have a great influence on the adsorption efficiency.

Abstract:The paper studied and analyzed the removal efficiency and influencing factors of 8 types of oil-absorbing materials on the petroleum pollutants in the source water. By comparing the adsorption capacity of 8 types of oil absorption materials of 4 sorts commonly used in the market to different oil products， it is found that the largest saturated adsorption capacity is cotton and the smallest is vermiculite. The absorbent material PP absorbent cotton has a saturated adsorption capacity of 9.0 ~ 13.0 g·g^-1 for pure phase oil and oil retention is approximately 60% ~ 70% for 30 minutes depending on the sort of oil. The adsorption of PP oil absorbent cotton on petroleum substances in oil-water mixture is completely physical adsorption， and the adsorption kinetics conforms to the pseudo-first-class kinetic model. The removal rate can reach 60% ~ 70% in 10 minutes， and 80% ~ 90% in 120 minutes. The key factor affecting the adsorption rate is the contact area between oil-absorbing cotton and oily water. The larger the coverage area， the better the adsorption effect.

Abstract:Sodium hypochlorite/ferrous salt coagulation can efficiently improve the dewatering performance and effect of algae-containing sludge. When the NaClO dosage was 1.5～2.0 mg·L^-1， the dewatering performance reached the best. The oxidizing property of excessive NaClO damaged the integrity of algae cells. The overflow of intracellular substances hindered the release of water between cells， leading to the decrease of dewatering performance. Under the oxidation effect of NaClO， Fe²⁺ was transformed into Fe³⁺ in situ and further formed Fe（OH）₃， which enhanced the coagulation effect. The hydrophilic components of extracellular polymeric substances such as protein and polysaccharides were partially degraded by NaClO， which was beneficial to the release of water between cells. Hence， the dewatering performance was improved. In addition， the removal rate of dissolved organic matter by NaClO/Fe²⁺ coagulation increased from 74% to 90%， and the content of humus macromolecules and aromatic compounds was also reduced， improving the purification effect of algae-laden water.

Abstract:Taking raw water from a water source in Shanghai as the research object， the effects of different pre-oxidation processes on the removal of characteristic pollutants were studied for the characteristic pollutants such as antibiotics and pesticides present in the source water. This study found that the ability of the removal of antibiotics under the same dose （0.2 ~ 0.8 mg·L^-1） of oxidant is ozone > potassium permanganate > free chlorine； the more dosage of each oxidant， the higher the removal rate of antibiotics. The ability of potassium permanganate to remove antibiotics first rises and then falls with pH increasing， while free chlorine and ozone gradually increases. The ability of removal of organic chlorine pesticides under the same dose oxidant is ozone > potassium permanganate > free chlorine. With the increase of pH， the removal ability of potassium permanganate to organic chlorine pesticides decreases， and the ability to remove ozone increases. The removal ability of free chlorine unchanged.

Abstract:With the off-flavor problem caused by chlorination of odor-related amino acids in Taihu Lake， the removal of O₃/H₂O₂ on odor-related amino acids in filtered water of a drinking water treatment plant of Taihu Lake and the impact factors were investigated. Result showed that the best dosages of O₃/H₂O₂ process were 1.5 mg/L O₃ and 0.06 mM H₂O₂， respectively， the removal rate of odor-related amino acids under the condition was up to 91.28%. The concentration of odor-related amino acids reduced to 484.62 ng/L， which has less potential of odorous problem during chlorination. Moreover， the bromate concentration reduced to 6.35 μg/L， which was lower than the limit of 10 μg/L. The removal rate of odor-related amino acids by O₃/H₂O₂ process increased with the temperature， and in the range of pH 6-8， the efficiency of O₃/H₂O₂ on odor-related amino acids removal increased when pH increased.

Abstract:To realize the application of ultraviolet advanced oxidation technology on removing antibiotics in actual water treatment， this study took chloramphenicol （CAP） as the research object， and compared its removal efficiency by ultraviolet technology， ultraviolet advanced oxidation technology （UV/ H₂O₂， UV/PS） under static and continuous flow respectively. The influence of factors such as ultraviolet light intensity， ultraviolet light wavelength， residence time， oxidant dosage， initial concentration of chloramphenicol and raw water quality on the removal effect was further analyzed. The study results show that the ultraviolet technology under static flow can degrade more than 80% chloramphenicol after an irradiation of 120 min， and the degradation conforms to the first-order kinetics. Chloramphenicol removal rate by ultraviolet technology under continuous flow is limited due to the short irradiation time， but UV/H₂O₂ and UV/PS processes can enhance the removal rate of chloramphenicol to 58% and 43%， owing to the oxidation effect of oxidizing free radicals activated by ultraviolet. Increasing the intensity of ultraviolet light， the dosage of oxidant and reducing the initial concentration of chloramphenicol will increase the degradation of chloramphenicol. The presence of inorganic and organic pollutants in raw water will reduce the removal efficiency of UV advanced oxidation technology for chloramphenicol， but the inorganic and organic pollutants can also be removed during the oxidation， which provides the possibility for the promotion and application of UV advanced oxidation technology on the actual water treatment.

Abstract:Carbon-to-nitrogen ratio （C/N） is one of the most important factors affecting aerobic denitrification effect. Based on the cyclic activated sludge system （CASS） process with low-carbon （C/N=1.8） influent， the effects of drainage ratio， aeration time， and water intake mode on denitrification effect are investigated separately. The results show that limited by the influent carbon source concentration， the drainage ratio is the main factor affecting the nitrogen removal efficiency. The average total nitrogen （TN）concentration of CASS effluent was 17.8 mg·L^-1， 9.5 mg·L^-1 and 6.6 mg·L^-1 when the drainage ratio was 30%， 40% and 50%， respectively； Therefore， for CASS process， the drainage ratio should be adjusted appropriately according to the carbon nitrogen ratio instead of being set to 30%.

Abstract:In order to evaluate the tensile mechanical behaviour of ionomer interlayer considering temperature effect and loading effect， monotonic tests at -40 °C ~ 80 °C， as well as cyclic loading-unloading tests at room temperature were conducted on ionomer interlayer specimens at low strain rates. Characteristic mechanical properties are extracted from the test results. As the strain rate increases and the temperature decreases， the material's strength increases but its ultimate strain decreases. The fractured specimen exhibits around 80% plastic deformation. The envelope of the cyclic loading and unloading curve is consistent with that of the monotonic curve. As the unloading strain increases， the hysteretic energy dissipation of the ionomer interlayer increases， while the secant unloading modulus decreases firstly and then increases. Based on the G'Sell model， a constitutive equation for low strain rates is proposed. Furthermore， a variable modulus model is proposed for the prediction of the material's loading-unloading behaviour and verified against the experimental results.

Abstract:Bond behaviors of sleeve grout and high strength steel rebar were investigated for the grouted sleeve connection. Taking the diameter of steel rebar and its embedded length into account， the pull-out test with 27 specimens was employed to investigate the bond behaviors between sleeve grout and steel rebar. Based on the test results， it is found that there are three failure patterns of specimens after loading， namely， steel rebar fracture， bond-slip failure and splitting failure， which were affected by the diameter of steel rebar and its embedded length especially. In addition， there is a sudden drop with a range of 0.1 to 0.3 times peak load in the initial decline part of load versus slip curves of specimens with bond-slip failure. Furthermore， bond-slip constitution models were initiated， and expressions of the bond strength， peak slip and residual bond strength were built by the data fitting for the specimens with bond-slip failure. Finally， the finite element analysis was used to stretch these previous expressions. Combined with the results of simulation and the test， it is found that the embedded length of steel rebars with a diameter （d） of 12mm， 16mm and 18mm should not be less than 5d， 7d and 7d respectively when the failure mode of rebar fracture occurs to the pull-out test. These findings are beneficial to the design of the grouted sleeve connection and form its bearing capacity calculation method in the further study.

Abstract:In order to investigate the morphological evolution characteristics of the nourished beach， the sediment transport and morphological model was applied and well verified against the measured data on the base of the well-validated wave-current coupled hydrodynamic model using the double nested grid technology. The model results and the measured beach profiles indicate some characteristics of the sediment concentration and the beach morphology： the sediment concentration distribution under the coupled tidal current and normal waves is consistent with that under the coupled tidal current and strong waves， and the averaged sediment concentration and the sediment concentration difference between post- and pre-engineering are larger at the maximum ebb than flood； in post-engineering scenario， the high sediment concentration area locates on the onshore side of the sandbars under the normal waves and on the offshore side under the strong waves； in post-engineering scenario， the erosion and deposition takes place at the sandbars and at the onshore area respectively， and the sandbars move onshore， which indicates that the nourishment project can protect the beach regardless of whether a storm surge occurs.

Abstract:To analyze the difference between traditional and network data envelopment analysis （DEA） in judging whether the airport operation is relatively inefficient， this paper made literature selection and data extraction on DEA and airport operation efficiency by formulating literature standards. Publication bias of selected studies is conducted， and heterogeneity and overall effect of extracted data is tested based on meta-analysis. The results show that the selected research and data have statistical significance， and the ratio of the number of relatively ineffective airports to the number of relatively effective airports obtained by the traditional DEA method is 0.17 times that of the network DEA method. Using network DEA method to judge whether the airport operation is relatively inefficient is truer and more accurate than traditional DEA method.

Abstract:Parking guidance system (GPS) is an effective way to alleviate traffic congestion, but as a key technology for releasing vacant parking spaces, the short-time accurate prediction of parking demand has not been effectively solved. Parking demand data were grouped based on the linear stability of the time-varying characteristic curves and the significant variability of the amplitudes among the working days. GRU (gated recurrent unit) Model was introduced to the accurate short-term prediction of parking demand. The model with a simpler logic gate control structure could memorize the time series data. Study results show that compared with the traditional neural network and ARIMA (autoregressive integrated moving average) Model, the proposed GRU model offers a satisfactory prediction accuracy.

Abstract:In order to study the orientation sensitivity for creep life of aero-engine nickel-based single crystal turbine blades serving under high temperature， creep tests of DD6 single crystal superalloy were carried out with three typical orientations ［001］， ［011］ and ［111］ at 980^oC， indicated that the creep life and elongation of the single crystal alloy are both ［111］ > ［001］ > ［011］. By analyzing the microstructure evolution during the creep process and the fracture morphology after creep fracture， the creep failure mechanism of single crystal alloy with different orientations is revealed. Based on the crystal plasticity theory， the viscoplastic constitutive equation and damage equation considering the orientation sensitivity of DD6 single crystal were established， which could well fit the strain-time curve of single crystal with different crystal orientations， and provided a reference for the strength analysis and life prediction of single crystal blade.

Abstract:In order to improve the water-holding capacity of sandy soil， and produce the super-hydrophobic material for ecological restoration ， this paper discusses the influence of raw materials， in which sandy soil is chosen as the core material， on impermeability and air permeability by adjusting the types and content of film covering material， changing the gradation of the core material and constructing nano rough structure on the surface of the core material. The results show that when selecting the film covering material， the surface energy should be less than 30mN·m^-1. To improve the impermeability of the material， the standard deviation α of the core material distribution should be greater than 0.35. In the case of material with low surface energy， adding nano material to increase the roughness is the key to further improve the impermeability of the super-hydrophobic material for ecological restoration. After filming the desert sand with 1% fluorosilicone resin and adding 0.3% nano-silica to construct nano rough structure， the super-hydrophobic material for ecological restoration obtained can withstand hydrostatic pressure up to 48cm.

Abstract:An investigation was made into the ownership distribution of 502 545 patents generated from the top 70 universities in China， and an analysis was made of the factors affecting the distribution of different ownership based on panel data. Results show that R&D staff size has a significantly positive effect on the patent R&D cooperation among universities and various organizations. Science and technology investments as well as the economic development level of the universities’ locations influences positively the invention patents， but negatively the proportion owned by individuals. Having medical school or related department influences positively the exclusive， other cooperative and enterprise-owned invention patents. University being polytechnic influences positively the exclusive and enterprise-owned invention patents， but negatively the proportion owned by individuals. Owning independent technology transfer agency influences positively the enterprise-owned invention patents. Royalty rate of the teacher influences positively the proportion of exclusive invention patents， but negatively the number and proportion of cooperative invention patents. While the equity rate is the opposite. Suggestions are put forward to improve the management level of scientific research achievements and promote technology transfer.

Abstract:In order to study the coordinated level of the port cluster and urban agglomeration， the evaluation index system of economic development quality of urban agglomeration and development level of port cluster in Yangtze River Delta region is constructed， and a gravity model is used to calculate the radiation capacity of each port in the port cluster to the urban agglomeration. On the basis of gravity model， a coupling degree model and a coupling coordination degree model are used to measure the coordinated development level of the Yangtze River Delta port cluster-urban agglomeration complex system， and calculate the coordinated development level of the port cluster which is used to analyze the influence of port co-opetition strategy on the coordination level of port cluster-urban agglomeration system. The results show that an initial coordinated layout has been formed between the port cluster and the urban agglomeration in Yangtze River Delta region， and it is moving forward to a high level of coordinated development. Besides， the trend that ports choose dislocation competition and active cooperation can enhance the level of integrated and coordinated development of port cluster and promote high-quality integrated development of the Yangtze River Delta.

Abstract:This study examines the determinants of goodwill impairment decisions， focusing on the exercising of discretion in goodwill impairment decisions by Chinese listed companies. Fixed-effect logistical regression findings indicate that incidence of goodwill impairment is negatively associated with a company’s operating cash-flow volatility， and the companies with stable profitability have higher incidence of goodwill impairment. In addition， goodwill impairment decisions in high goodwill balance companies or non-state-owned companies tend to be more responsive to operating cash-flow volatility and stability of profitability； Compared with the first 6 years after the adaption of the Accounting Standards for Enterprises No.8—Impairment of Assets， the incidences of goodwill impairment are more significantly associated with operating cash-flow volatility and stability of profitability in the second 6 years. These evidences suggest that discretion is exercised opportunistically by listed companies according to their operating and profitable status when making goodwill impairment decisions.