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Urban stormwater disinfection, quality variability during storage and influence on the freshwater algae: Implications for reuse safety

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Journal of Environmental Sciences 2023年第2期124卷 655-666页

作者： Shanshan Fan gang wen An Liu College of Chemistry and Environmental Engineering Shenzhen UniversityShenzhen 518060China Shaanxi Key Laboratory of Environmental Engineering Xi’an University of Architecture and TechnologyXi’an 710055China Water Science and Environmental Engineering Research Center College of Chemistry and Environmental EngineeringShenzhen UniversityShenzhen 518060China

Stormwater reuse is one of the most important ways to mitigate water resource ***,urban stormwater contains many bacteria species,which threaten the reuse ***,stormwater disinfection is highly *** disinfection has been widely conducted in the drinking water and reclaimed water,it is rarely carried out for *** study collected the roof stormwater and undertook chlorination *** typical bacteria,Escherichia coli(***)and Staphylococcus aureus(***)were selected in this study to investigate the disinfection *** is found that bacteria species present in the stormwater had an important influence on disinfection efficiency while the original stormwater quality did not show an obvious ***,when the disinfected stormwater was stored,the stormwater quality was highly variable during its storage process and the variability was affected by bacteria *** *** containing stormwater showed a high variability of quality and *** significantly ***,the *** containing stormwater quality had a relatively low variability and *** did not significantly ***,it is noted that after storage,the dissolved form of stormwater was more positive to the freshwater algae’s growth while the particulate form(including bacteria and other particulate matters)was *** implies that a further treatment such as filtration is needed before the stored stormwater is recharged into receiving waters in order to remove particulate *** research outcomes can provide useful insight to effective stormwater disinfection and ensure reuse safety.

关键词： Stormwater quality Stormwater disinfection Stormwater storage Stormwater reuse Escherichia coli Staphylococcus aureus

Discovery of Fractionalized Neutral Spin-1/2 Excitation of Topological Order

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Chinese Physics Letters 2017年第9期34卷 1-2页

作者： Xiao-gang wen Department of Physics Massachusetts Institute of Technology Cambridge Massachusetts 02139 USA

After the discovery of fraction quantum Hall states in the 1980s, it became more and more clear that Landau symmetry breaking theory does not describe all possible quantum phases of matter. The new quan- tum phases of matter were called topologically ordered phases（for gapped cases） or quantum ordered phases （for gapless cases）, which correspond to pat- terns of many-body entanglement. One may won- der： besides quantum Hall systems, are there other systems that realize the new topological/quantum order？

关键词： Discovery of Fractionalized Neutral Spin-1/2 Excitation of Topological Order

Lung tissue flap repairs esophagus defection with an inner chitosan tube stent

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World Journal of Gastroenterology 2009年第12期15卷 1512-1517页

作者： gang Chen wen-Jun Shi Department of Thoracic Surgery Shengjing Hospital China Medical University Shenyang 110004 Liaoning Province China

AIM： TO repair the partial esophagus defect with a chitosan stent, a new esophageal prosthesis made of pulmonary tissue with vascular pedicie.METHODS： Fifteen Japanese big ear white rabbits were divided into experimental group （n = 10） and control group （n = 5）. Esophagus defect in rabbits of experimental group was repaired using lung tissue flap with a chitosan tube stent, gross and histological appearance was observed at week 2, 4 and 8 after operation, and barium sulphate X-ray screen was performed at week 10 after operation. Esophagus defect of rabbits in control group was repaired using lung tissue flap with no chitosan tube stent, gross and histological appearance was observed at week 2, 4 and 8 after operation, and barium sulphate X-ray screen was performed at week 10 after operation.RESULTS： In the experimental group, 6 rabbits survived for over two weeks, the lung tissue flap healed esophageal defection, and squamous metaplasia occurred on the surface of lung tissue flap. At week 10 after operation, barium sulphate examination found that barium was fluent through the esophagus with no stricture or back stream, the creeping was good. In the control group, 4 rabbits survived for two weeks, the lung tissue flap healed esophageal defection with fibrous tissue hyperplasia, barium sulphate examination found that barium was fluent through the esophagus with a slight stricture or back stream, and the creeping was not good at week 10 after operation.CONCLUSION： Esophagus defect can be repaired using lung tissue flap with an inner chitosan tube stent.

关键词： Lung Tissue flap Chitosan Stent Esophagus reconstruction

Nonequilibrium Thermodynamics of Dark Energy on Cosmic Apparent Horizon

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Communications in Theoretical Physics 2009年第8期52卷 383-384页

作者： WANG gang LIU wen-Biao Department of Physics Institute of Theoretical Physics Beijing Normal University Beijing 100875 China

In recent several years,some works have been done on cosmic *** apparent horizonwas regarded as the key characteristic supersurface where thermodynamics can be built on ***,if theirreversible process is considered,the proper position for building thermodynamics will not be the apparent *** new position is related to dark energy state equation and the irreversible process parameters.

关键词： cosmology dark energy linear nonequilibrium thermodynamics entropy apparent horizon

The simultaneous removal of ammonium and manganese from surface water by MeO_x:Side effect of ammonium presence on manganese removal

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Journal of Environmental Sciences 2019年第3期31卷 346-353页

作者： Xuan Tian Ruifeng Zhang Tinglin Huang gang wen Key Laboratory of Northwest Water Resource Environment and Ecology MOE Xi'an University of Architecture and Technology Shaanxi Key Laboratory of Environmental Engineering Xi'an University of Architecture and Technology

Manganese and ammonium pollution in surface water sources has become a serious *** this study, a pilot-scale filtration system was used to investigate the effect of ammonium on manganese removal during the simultaneous removal of ammonium and manganese from surface water using a manganese co-oxide filter film(MeO_x ). The results showed that the manganese removal efficiency of MeO_x in the absence of ammonium was high and stable, and the removal efficiency could reach 70% even at 5.5 °C. When the influent ammonium concentration was lower than 0.7 mg/L, ammonium and manganese could be removed simultaneously. However, at an ammonium concentration of 1.5 mg/L, the manganese removal efficiency of the filter gradually decreased with time(from 96% to 46.20%). Nevertheless, there was no impact of manganese on ammonium removal. The mechanism by which ammonium negatively affected manganese removal was investigated, demonstrating that ammonium affected manganese removal mainly through two possible mechanisms. On one hand, the decreased p H caused by ammonium oxidation was unfavorable for the oxidation of manganese by MeO_x ; on the other hand, the presence of ammonium slowed the growth of new MeO_x and retarded the increase in the specific surface area of the Me Ox-coated sand, and induced changes in the morphology and crystal structure of Me Ox. Consequently, the manganese removal efficiency of the filter decreased when ammonium was present in the inlet water.

关键词： Surface water Manganese Ammonium MeO_x Side effect

Comparisons of the film peeling from the composite oxides of quartz sand filters using ozone, hydrogen peroxide and chlorine dioxide

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Journal of Environmental Sciences 2015年第8期27卷 20-27页

作者： Yingming Guo Tinglin Huang gang wen Xin Cao School of Environmental and Municipal Engineering Xi'an University of Architecture and Technology

To solve the problem of shortened backwashing intervals in groundwater plants, several disinfectants including ozone（O3）, hydrogen peroxide（H2O2） and chlorine dioxide（Cl O2）were examined to peel off the film from the quartz sand surface in four pilot-scale *** optimized oxidant dosage and oxidation time were determined by batch ***, the optimized conditions were tested in the four pilot-scale columns. The results demonstrated that the backwashing intervals increased from 35.17 to 54.33（H2O2）and to 53.67 hr（ClO2） after the oxidation treatments, and the increase of backwashing interval after treatment by O3 was much less than for the other two ***, the treatment efficiency of filters was not affected by O3 or H2O2 oxidation;but after oxidation by ClO2, the treatment efficiency was deteriorated, especially the ammonia removal（from 96.96% to 24.95%）. The filter sands before and after the oxidation were characterized by scanning electron microscopy and X-ray photoelectron *** with the oxidation by O3 and H2O2, the structures on the surface of filter sands were seriously damaged after oxidation by ClO2. The chemical states of manganese on the surfaces of those treated sands were only changed by ClO2. The damage of the structures and the change of the chemical states of manganese might have a negative effect on the ammonia removal. In summary, H2O2 is a suitable agent for film peeling.

关键词： Pilot-scale Ozone Hydrogen peroxide Chlorine dioxide Backwashing interval

Undersea safety mining of the large gold deposit in Xinli District of Sanshandao Gold Mine

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International Journal of Minerals,Metallurgy and Materials 2012年第7期19卷 574-583页

作者： Zhi-xiang Liu wen-gang Dang Xian-qun He School of Resources and Safety Engineering Central South University Changsha 410083 China

The exploration of undersea resources becomes popular as land resources decrease. Researches were conducted with emphasis on the safety and efficiency of undersea mining of the large gold deposit in Xinli District of Sanshandao Gold Mine. A series of tests for the physical and mechanical characteristics of rock mass were carried out, and the three-dimensional geo-stress distribution was tested in the mining area. Further, a similar experimental simulation platform, which revealed the mechanism of water inrush and ascertained the reason- able thickness of the safety isolate layer, was established for the undersea mining. Meanwhile, the feasibility of cancelling the ore pillars and the safety conditions was checked by numerical simulation. The simulation results show that it is safe to exploit the ore body below the -85 m level （presently, the exploitation level is below -160 m in Xinli District）, and the ore pillars can be cancelled below the -560 m level. Fur- thermore, a novel backfill method was designed to reduce the rock strata disturbance and settlement, and the settlement of roof strata was monitored during the mining process. Engineering practice shows that the settlement of roof strata was small and that no disaster happened. This indicates that the undersea safety mining technology of the large gold deposit is achieved in Xinli District.

关键词： undersea mining gold deposits rock mechanics mine roof control computer simulation

Aging of PVDF and PES ultrafiltration membranes by sodium hypochlorite:Effect of solution pH

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Journal of Environmental Sciences 2021年第6期33卷 444-455页

作者： Kai Li Qian Su Shu Li gang wen Tinglin Huang Key Laboratory of Northwest Water Resource Environment and EcologyMOEXi’an University of Architecture and TechnologyXi’an 710055China Shaanxi Key Laboratory of Environmental Engineering Xi’an University of Architecture and TechnologyXi’an 710055China

Sodium hypochlorite(NaClO)is a commonly applied cleaning agent for ultrafiltration membranes in water and wastewater ***-term exposure to NaClO might change the properties and performance of polymeric membranes,and ultimately shorten membrane *** species in NaClO solution vary with solution pH,and the aging effects can change depending on the membrane *** this study,the aging of polyvinylidene fluoride(PVDF)and polyethersulfone(PES)membranes by NaClO at pH 3–11 was investigated by examining variations in chemical composition,surface charge,surface morphology,mechanical strength,permeability,and retention *** pyrrolidone(PVP),which was blended in both membranes,was oxidized and dislodged due to NaClO aging at all investigated pH values,but the oxidation products and dislodgement ratio of PVP varied with solution *** the PVDF membrane,NaClO aging at pH 3–11 caused a moderate increase in permeability and decreased retention due to the oxidation and release of *** tensile strength decreased only at pH 11 because of the defluorination of PVDF *** the PES membrane,NaClO aging at all investigated pH resulted in chain scission of PES molecules,which was favored at pH 7 and 9,potentially due to the formation of free ***,a decrease in tensile strength and retention ability,as well as an increase in permeability,occurred in the PES membrane for NaClO aging at pH 3–***,the results can provide a basis for selecting chemical cleaning conditions for PVDF and PES membranes.

关键词： Polymeric ultrafiltration(UF)membrane Membrane aging Sodium hypochlorite(NaClO) Membrane properties Performance factors

Separation of tungsten and molybdenum with solvent extraction using functionalized ionic liquid tricaprylmethylammonium bis(2,4,4-trimethylpentyl)phosphinate

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International Journal of Minerals,Metallurgy and Materials 2021年第11期28卷 1769-1776页

作者： Fei Cao Wei Wang De-zhou Wei wen-gang Liu School of Resource and Civil Engineering Northeastern UniversityShenyang 110819China Zhengzhou Institute of Multipurpose Utilization of Mineral Resources CAGSZhengzhou 450006China Key Laboratory for Polymetallic Ores’Evaluation and Utilization MNRZhengzhou 450006China

Functionalized ionic liquids(FILs)as extractants were employed for the separation of tungsten and molybdenum from a sulfate solution for the first *** effects of initial pH,extractant concentration,metal concentrations in the feed were comprehensively *** results showed that tricaprylmethylammonium bis(2,4,4-trimethylpentyl)phosphinate([A336][Cyanex272])could selectively extract W over Mo at an initial pH value of 5.5;the best separation factorβ_(W/Mo) of 25.61 was obtained for a solution with low metal concentrations(WO3:2.49 g/L,Mo:1.04 g/L).The[A336][Cyanex272]system performed effectively for solutions of different W/Mo molar ratios and different metal ion concentrations in the *** chemical reaction between[A336][Cyanex272]and W followed the ion association mechanism,which was further proved by the Fourier-transform infrared(FTIR)spectra of loaded[A336][Cyanex272]and the free *** stripping experiments indicated that 95.48%W and 100.00%Mo were stripped using a 0.20 mol/L sodium hydroxide ***,the selective extractions of W and Mo from two synthetic solutions of different high metal concentrations were obtained;the separation factorβW/Mo reached 23.24 and 17.59 for the first and second solutions,*** results suggest the feasibility of[A336][Cyanex272]as an extractant for the separation of tungsten and molybdenum.

关键词： tungsten molybdenum ionic liquid separation solvent extraction