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Material conversion from paper sludge ash in NaOH solution to synthesize adsorbent for removal of Pb^(2+),NH_4^+and PO_4^(3-) from aqueous solution

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Journal of Environmental Sciences 2011年第5期23卷 718-724页

作者： Takaaki Wajima Kenzo Munakata faculty of engineering and resource Sciences Akita University

Material conversion from paper sludge ash （PSA） in NaOH solution was attempted to synthesize the adsorbent for removal of inorganic pollutants, such as Pb^2＋, NH^4＋ and PO4^3- from aqueous solution. PSA of 0.5 g was added into 10 mL of 3 mol/L NaOH solution, and then heated at 80, 120, and 160℃ for 6-48 hr to obtain the product. PSA mainly composed of two crystalline phases, gehlenite （Ca2Al2SiO7） and anorthite （CaAl2Si2O8）, and amorphous phase. Hydroxysodalite （Na6Al6Si6O24-8H2O） was formed at 80℃, and anorthite dissolved, whereas gehlenite remained unaffected. Katoite （Ca3Al2SiO4（OH）8） was formed over 120℃, and hydroxycancrinite （Nas（OH）2Al6Si6O24·2H2O） was formed at 160℃, due to the dissolution of both gehlenite and anorthite. Specific surface areas of the products were almost same and were higher than that of raw ash. Cation exchange capacities （CECs） of the products were also higher than that of raw ash, and CEC obtained at lower temperature was higher. Removal abilities of products for Pb^2＋, NH4＋, and PO4^3- were higher than that of raw ash. With increasing reaction temperature, the removal efficiencies of Pb^2＋ and NH4＋ decreased due to the decrease of CEC of the product, while removal efficiency for PO4^3- was almost same. The concentrations of Si and AI in the solution and the crystalline phases in the solid during the reaction explain the formation of the product phases at each temperature.

关键词： paper sludge ash hydrothermal synthesis gehlenite anorhite heavy metal ion ammonium ion phosphate ion

Brain age estimation:premise,promise,and problems

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Neural Regeneration Research 2025年第8期20卷 2313-2314页

作者： Jarrad Perron Ji Hyun Ko Graduate Program in Biomedical engineering Price Faculty of EngineeringUniversity of ManitobaWinnipegMBCanada PrairieNeuro Research Centre Kleysen Institute for Advanced MedicineHealth Sciences CentreWinnipegMBCanada Department of Human Anatomy and Cell Science Rady Faculty of Health SciencesUniversity of ManitobaWinnipegMBCanada

Premise:The com bined effects of modern healthcare practices which prolong lifespan and declining birthrates have created unprecedented changes in age demographics worldwide that are especially pronounced in Japan,South Korea,Europe,and North *** old age is the most significant predictor of dementia,global healthcare systems must rise to the challenge of providing care for those with neurodegenerative disorders.

关键词： estimation providing birth

Membrane Fouling in Microfiltration of Sanitary Landfill Leachate for Removals of Colourand Solids

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应用与环境生物学报 2013年第1期19卷 184-188页

作者： Emad S.M.Ameen water Research Alliance Institute of Environmental and Water Resource ManagementFaculty of Civil EngineeringUniversiti Teknologi Malaysia

In this research,the treatability of solids from sanitary landfill leachate by microfiltration membrane was investigated and the fouling of the membrane was carefully *** microfiltration process was carried out for 21 h in experimental system involved coagulation with Moringa oleifera followed by filtration using submerged hollow fibre microfiltration membrane (MFM).Coagulation with ***,air diffusers and back flush technique were used for preventing or alleviating fouling of the *** hollow fibre MFM showed high removals of 98%,91% and 99% for turbidity,colour and total suspended solids *** was obtained at the beginning of the ***,quality of the filtrate rapidly declined during the filtration *** was found to proceed according to the classical cake filtration *** with *** as well as the back-flush technique could not fully restore the deterioration occurred to the membrane.

关键词： RAPD ISSR AFLP 环境生物学

Effect of Under Connected Plates on the Hydrodynamic Efficiency of the Floating Breakwater

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China Ocean engineering 2014年第3期28卷 349-362页

作者： A.S.Koraim O.S.Rageh water and water Structure engineering Department Faculty of EngineeringZagazig University Irrigation and Hydraulics Department Faculty of Engineering El-Mansoura University

In this paper, the hydrodynamic efficiency of a floating breakwater system is experimentally studied by use of physical models. Regular waves with wide ranges of wave heights and periods are tested. The efficiency of the breakwater is presented as a function of the wave transmission, reflection, and energy dissipation coefficients. Different parameters affecting the breakwater efficiency are investigated, e.g. the number of the under connected vertical plates, the length of the mooring wire, and the wave length. It is found that, the transmission coefficient kt decreases with the increase of the relative breakwater width B/L, the number of plates n and the relative wire length l/h, while the reflection coefficient kr takes the opposite trend. Therefore, it is possible to achieve kt values smaller than 0.25 and kr values larger than 0.80 when B/L is larger than 0.25 for the case of l/h-1.5 and n=4. In addition, empirical equations used for estimating the transmission and reflection coefficients are developed by using the dimensionless analysis, regression analysis and measured data and verified by different theoretical and experimental results.

关键词： floating breakwaters vertical plates regular waves transmission reflection energy dissipation

Evaluation of the parameters affecting the roughness coefficient of sewer pipes with rigid and loose boundary conditions via kernel based approaches

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International Journal of Sediment Research 2020年第2期35卷 171-179页

作者： Kiyoumars Roushangar Roghayeh Ghasempour Sanam Biukaghazadeh Department of water resource engineering Faculty of Civil EngineeringUniversity of Tabriz Center of Excellence in Hydroinformatics University of Tabriz

One of the important issues in water transport and sewer systems is determining the flow resistance and roughness *** accurate estimation of the roughness coefficient is a substantial issue in the design and operation of hydraulic structures such as sewer pipes,the calculation of water depth and flow velocity,and the accurate characterization of energy *** current study,applies two kernel based approaches [Support Vector Machine(SVM) and Gaussian Process Regression(GPR)] to develop roughness coefficient models for sewer *** the modeling process,two types of sewer bed conditions were considered:loose bed and rigid *** order to develop the models,different input combinations were considered under three scenarios(Scenario 1:based on hydraulic characteristics,Scenarios2 and 3:based on hydraulic and sediment characteristics with and without considering sediment concentration as input).The results proved the capability of the kernel based approaches in prediction of the roughness coefficient and it was found that for prediction of this parameter in sewer pipes Scenario 3 performed better than Scenarios 1 and ***,the sensitivity analysis results showed that Dgr(Dimensionless particle number) for a rigid bed and wb/y(ratio of deposited bed width,wb,to flow depth,y) for a loose bed had the most significant impact on the modeling process.

关键词： Gaussian process regression Loose bed Rigid bed Roughness coefficient Sewer pipes Support vector machine

Regulating the oxygen-atom configuration of carbon anode enabling extremely fast-charging potassium-ion hybrid capacitors

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Nano Research 2025年第1期18卷 373-381页

作者： Daping Qiu Yuehui Wang Lulu Zhang Hang Lei Haizhou Ying Jin Niu Min Li Xuelin Yang Feng Wang Ru Yang Hubei Provincial Collaborative Innovation Center for New Energy Microgrid College of Electrical Engineering and New EnergyChina Three Gorges UniversityYichang 443002China State Key Laboratory of Chemical resource engineering Laboratory of Electrochemical Process and Technology for MaterialsBeijing University of Chemical TechnologyBeijing 100029China College of Materials and Chemical engineering China Three Gorges UniversityYichang 443002China

Metal-ion hybrid capacitors,such as potassium-ion hybrid capacitors(PIHCs),are regarded as promising fast-charging energy storage ***,the kinetics mismatch between the battery anode and the capacitive cathode restricts their fastcharging *** constructing carbon anodes with enhanced kinetics is an innovative approach to address this ***,using epigallocatechin gallate with high oxygen content as the precursor,oxygen-enriched carbon materials(OEC)with tunable C=O content are successfully ***,the C=O content of OEC is regulated by adjusting the pyrolysis *** as an anode for PIHCs,OEC-600 with the highest C=O content exhibits an attractive fast-charging specific capacity of 135.2 mAh·g^(-1)at 20 A·g^(-1),along with a superior fast-charging cycling *** theoretical calculations,comprehensive kinetics analysis and in-situ Raman,the positive effects of C=O on the potassium storage capability and reversibility of OEC-600 are ***,PIHCs assembled based on an OEC-600 anode deliver impressive energy/power density of 145.1 Wh·kg^(-1)/45.9 kW·kg^(-1)and superior fast-charging cycling stability with 87.5%of capacity retention over 20,000 cycles at 5 A·g^(-1).This work is anticipated to provide an optional design concept toward the carbon anode for fast-charging PIHCs.

关键词： carbon anode oxygen epigallocatechin gallate potassium-ion hybrid capacitor

Heavy metal removal from aqueous solution using carbonaceous K_2S-impregnated adsorbent

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Journal of Environmental Sciences 2009年第12期21卷 1730-1734页

作者： Takaaki Wajima Kenji Murakami Takahiro Kato Katsuyasu Sugawara faculty of engineering and resource Science Akita University

A novel carbonaceous adsorbent for heavy metal removal was prepared from raw coal by one-step simple sulfur impregnation using K2S. Raw coal was mixed with K2S powder and then heated at 800℃ for 30 min in nitrogen to produce K2S char. The sulfur content and form in K2S char were determined, and the ability of K2S char to adsorb Zn^2＋, Cd^2＋ and Pb^2＋ was examined. The K2S impregnation was effective at impregnating sulfur into coal, especially in the form of elemental, thiophenic and sulfatic sulfur. The sulfur content of K2S char was higher than those of raw coal and pyrolysis char. The Zn^2＋ removal in 2.4 mmol/L of Zn^2＋ solution by K2S char was higher than raw coal with the removal rate of 100%. K2S char adsorbed Pb^2＋ and Cd^2＋ in 24 mmol/L of Pb^2＋ and Cd^2＋ solution with the removal rate of 97% and 35%, respectively. The elution extents of adsorbed Pb^2＋ and Cd^2＋ were zero in distilled water and 27% in 0.1 mol/L HCl solution. These results indicated that an effective adsorbent for heavy metal ions was prepared from coal using K2S sulfur impregnation, and that the adsorbed metals were strongly retained in K2S char.

关键词： sulfur impregnation carbonaceous adsorbent K2S heavy metal adsorption

Sediment Transport Capacity Under the River–Tide Interaction in the Changjiang Estuary

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China Ocean engineering 2019年第2期33卷 207-218页

作者： FENG Zhi-yong TAN Guang-ming XIA Jun-qiang State Key Laboratory of water resource and Hydropower engineering Science Wuhan University

Sediment transport capacity is a fundamental parameter in sediment transport theory and its accurate calculation is important from both theoretical and engineering viewpoints. The capacity of sediment transport has been studied extensively by many researchers in the last decades. Nevertheless, the underlying mechanism behind sediment transport capacity in estuaries remains poorly understood. The current study aims to explore the impact of the river–tide interaction on sediment transport and establish a formula of sediment transport capacity under the river–tide interaction. The impact of the river–tide interaction on the hydrodynamics and sediment dynamics in the Changjiang Estuary was analyzed, a practical method for describing the variation in tide-runoff ratio was established,and a formula of sediment transport capacity considering the impact of river–tide interaction was proposed by introducing the tide-runoff ratio. The new method bridged the gap between two well-known sediment transport capacity methods by considering the variation in the index a for the gravitational term and overcomes the drawback of distinguishing flood/dry season or spring/ebb tide in the calculation of estuarine sediment transport. A large amount of flow and sediment data obtained from the Changjiang Estuary were collected to verify the proposed formula. The effect of salt-fresh water mixture and the morphological evolution on sediment transport capacity of the Changjiang Estuary were discussed.

关键词： sediment transport capacity river tide interaction hydrodynamics and sediment dynamics Changjiang Estuary (Yangtze Estuary)

Experimental and numerical analysis of flow over a rectangular full-width sharp-crested weir

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water Science and engineering 2018年第1期11卷 75-80页

作者： Ghorban Mahtabi Hadi Arvanaghi Department of water engineering Faculty of Agriculture University of Zanjan Department of water engineering Faculty of Agriculture University of Tabriz

Weirs are a type of hydraulic structure, used for water level adjustment, flow measurement, and diversion of water in irrigation systems. In this study, experiments were conducted on sharp-crested weirs under free-flow conditions and an optimization method was used to determine the best form of the discharge coefficient equation based on the coefficient of determination （R2） and root mean square error （RMSE）. The ability of the numerical method to simulate the flow over the weir was also investigated using Fluent software. Results showed that, with an increase of the ratio of the head over the weir crest to the weir height （h/P）, the discharge coefficient decreased nonlinearly and reached a constant value of 0.7 for hiP 〉 0.6. The best form of the discharge coefficient equation predicted the discharge coefficient well and percent errors were within a ±5% error limit. Numerical results of the discharge coefficient showed strong agreement with the experimental data. Variation of the discharge coefficient with Reynolds numbers showed that the discharge coefficient reached a constant value of 0.7 when hiP 〉 0.6 and Re 〉 20000.

关键词： Discharge coefficient Measurement Numerical model Sharp-crested weir Weir height