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Performance of hybrid constructed wetland systems for treating septic tank effluent

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Journal of Environmental Sciences 2006年第4期18卷 665-669页

作者： CUI li-hua liu wen ZHUxi-zhen MA mei HUANG xi-hua xiA Yan-yang Department of Environmental Science and Engineering South China Agricultural University Guangzhou 510642 China Coast to Coast Analytical Specialists Garland TX 75081 USA

The integrated wetland systems were constructed by combining horizontal-flow and vertical-flow bed, and their purification efficiencies for septic tank effluent were detected when the hydraulic retention time （HRT） was 1 d, 3 d, 5 d under different seasons. The results showed that the removal efficiencies of the organics, phosphorus were steady in the hybrid systems, but the removal efficiency of total nitrogen was not steady due to high total nitrogen concentration in the septic tank effluent. The average removal rates of COD （chemical oxygen demand） were 89%, 87%, 83%, and 86% in summer, autumn, winter and spring, respectively, and it was up to 88%, 85%, 73%, and 74% for BOD5 （5 d biochemical oxygen demand） removal rate in four seasons. The average removal rates of TP （total phosphorous） could reach up to 97%, 98%, 95%, 98% in four seasons, but the removal rate of TN （total nitrogen） was very low. The results of this study also indicated that the capability of purification was the worst in winter. Cultivating with plants could improve the treated effluent quality fTom the hybrid systems. The results of the operation of the horizontal-flow and vertical-flow cells （hybrid systems） showed that the removal efficiencies of the organics, TP and TN in horizontal-flow and vertical-flow cells were improved significantly with the extension of HRT under the same season. The removal rate of 3 d HRT was obviously higher than that of 1 d HRT, and the removal rate of 5 d HRT was better than that of 3 d HRT, but the removal efficiency was not very obvious with the increment of HRT. Therefore, 3 d HRT might be recommended in the actual operation of the hybrid systems for economic and technical reasons.

关键词： constructed wetlands hybrid system horizontal-flow vertical-flow removal efficiency septic tank effluent

Analysis of risk factors for retinopathy of prematurity

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International Journal of Ophthalmology(English edition) 2011年第6期4卷 631-633页

作者： wen-lin li li He xi-Hua liu Yu-mei Wang and Jian-Qing liu Department of Ophthalmology Shenzhen Children's Hospital Shenzhen 518026 Guangdong Province China

AIM: To analyze the incidence and risk factors for retinopathy of prematurity (ROP). METHODS: A retrospective analysis was conducted on 568 premature infants from September 2005 to December 2010 with birth weight (BW) equal to or less than 2 500g or a gestational age (GA) at birth of 34 weeks or less. All of the members were examined by indirect binocular ophthalmoscopy. RESULTS: ROP occurred with an incidence rate of 10.7% among 568 premature infants, and stages 3 and above ROP occurred with an incidence rate of 2.5%. This study showed the infants were more prone to develop ROP with short geststional age, low BW, long time of oxygen inhalation, and severe infants diseases. Twins had a significantly higher rate of ROP (18.3%) than singleton babies (9.8%), ROP were severer in twins than singleton babies. CONCLUSION: Short GA, low BW, long time of oxygen inhalation, severe infants diseases, and non-singleton babies were the most significant risk factors associated with ROP.

关键词： retinopathy of prematurity ROP epidemiology ROP incidence

Aging precipitation characteristics and tensile properties of Al-Zn-Mg-Cu alloys with different additional Zn contents

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Rare Metals 2021年第8期40卷 2160-2166页

作者： Kai wen bai-Qing xiong Yong-An Zhang xi-Wu li Zhi-Hui li li-Zhen Yan Hong-Wei Yan Hong-Wei liu State Key Laboratory of Nonferrous Metals and Processes GRIMAT Engineering Institute Co.LTD.Beijing101407China GRINM Group Co. LTD.Beijing100088China

The increase in zinc content in Al-Zn-Mg-Cu alloys provides an effective method to enhance the *** electron microscopy(TEM)and tensile test were employed to analyze the microstructure and tensile properties,respectively,of Al-9.3 Zn-2.0 Mg-1.8 Cu alloy(9.3 Zn alloy)and Al-9.8 Zn-2.0 Mg-1.8 Cu alloy(9.8 Zn alloy)with single-and double-stage aging *** results showed that the two alloys possessed a closed strength under single-stage peak-aging *** for double-stage aging treatment,9.8 Zn alloy had a higher strength values than 9.3 Zn alloy under the same aging *** the second step aging time prolonging,the strength gap was *** main precipitates for the two alloys with single-stage peak-aging state were GP zones andη’phase,while there were a majority ofη’phases andηphases for the two alloys under typical double-stage over-aging *** double-stage overaging state,the proportion of precipitate with large size for9.3 Zn alloy was larger than that for 9.8 Zn ***,a more obvious trend was revealed for the double-stage overaging *** gap of strength between the two alloys was explained by the difference of precipitation characteristics via interaction mechanism between precipitates and dislocations.

关键词： Zn content Al-Zn-Mg-Cu alloy Precipitation characteristics Tensile properties

3D Urban Visualization with LOD Techniques

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Journal of China University of Mining and Technology 2006年第1期16卷 64-67页

作者： Wang Yin-xing li bai-ying liu wen-bao Shi xing-xi College ofGeosciences Shandong University of Science and Technology Taian Shandong 271019 China Nanjing University of Science and Technology Nanjing Jiangsu 210000 China

In 3D urban visualization, large data volumes related to buildings are a major factor that limits the delivery and browsing speed in a web-based computer system. This paper proposes a new approach based on the level of detail （LOD） technique advanced in 3D visualization in computer graphics. The key idea of LOD technique is to generalize details of object surfaces without losing details for delivery and displaying objects. This technique has been successfully used in visualizing one or a few multiple objects in films and other industries. However, applying the technique to 3D urban visualization requires an effective generalization method for urban buildings. Conventional two-dimensional （2D） generalization method at different scales provides a good generalization reference for 3D urban visualization, Yet, it is difficult to determine when and where to retrieve data for displaying buildings. To solve this problem, this paper defines an imaging scale point and image scale region for judging when and where to get the fight data for visualization. The results show that the average response time of view transformations is much decreased.

关键词： digital city level of detail (LOD) generalization visualization image scale point/region

Interfacial Banded Transcrystallization of Polyoxymethylene/Poly(butylene succinate) Blends Induced by the Polyamide 6 Fiber

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Chinese Journal of Polymer Science 2022年第4期40卷 394-402页

作者： Zi-li Zheng wen-Jing Sun xi-xi Zhang Zhou-Yun-Tong liu wen-Bin Wang Meng-Han bai Hao-Ran Yang Gan-Ji Zhong Jia-Zhuang Xu Zhong-Ming li College of Polymer Science and Engineering and State Key Laboratory of Polymer Materials Engineering Sichuan UniversityChengdu 610065China State Laboratory of Surface and Interface Science and Technology School of Material and Chemical EngineeringZhengzhou University of Light IndustryZhengzhou 450002China

Interfacial crystallization of polyoxymethylene/poly(butylene succinate)blends induced by the polyamide 6(PA6)fiber was *** to strong heterogeneous nucleating ability,dense nuclei were generated on the surface of the PA6 fiber,which compelled the growth of twisted lamellae perpendicular to the PA6 *** a result,unique interfacial banded transcrystallization was formed,which is rarely found *** temperature was dominant in determining the nucleation activity of the PA6 fiber,further affecting the architecture of banded *** the increase of crystallization temperature,the nucleation density decreased to give more growth space for the twisted lamellae around the *** wave-like banded stripes were transformed into fan-like ***,band spacing and eccentricity respectively showed positive and negative correlation with crystallization *** meaningful results shed light on regulating the architecture of banded crystals in polymer composites.

关键词： Interfacial crystallization Banded transcrystallization Heterogeneous fiber Nuclei density Polymer blends

TiO_2 photocatalytic antifungal technique for crops diseases control

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Journal of Environmental Sciences 2006年第2期18卷 397-401页

作者： LU Jian-wei li Fang-bai GUO Ting liN Lan-wen HOU mei-fang liu Tong-xu Faculty of Resource and Environment Center China Agricultural University Wuhan 430070 China Guangdong Key Laboratory of Agricultural Environment Pollution Integrated Control Guangdong Institute of Eco-Environment and Soil Sciences Guangzhou 510650 China South China Institute of Botany Chinese Academy of Sciences Guangzhou 510650 China

TiO2 and 1% Ce^3＋-TiO2 prepared by hydrothermal method were characterized by means of XRD and UV-visible diffusive reflectance spectra（DRS）. The results of DRS analysis indicated that the 1% Ce^3＋-TiO2 catalyst had significant optical absorption in the visible region between 400-450 nm because electrons could be excited from the valence band of TiO2 or cerium oxides to Ce 4f level. To investigate the photocatalytic activity of different catalysts for crop fungal disease control, a series of Quine tests were carried out for cucumber powdery mildew and litchi downy blight control in home-made photocatalytic reactor. The results showed that TiO2 photocatalysis technique should be effective to inhibit the growth of fungal diseases to some extent and P-25 had a higher activity for antifungal control than home-made TiO2 catalysts. TiO2-A prepared with Ti（SO4）2 is more active to contro 1 antifungal disease than TiO2-B prepared with TiOSO4 as precursor because the crystalline of TiO2-A was higher than that of TiO2-B. The antifungal index litchi downy blight control was greatly enhanced by doping 1% cerium ion. The antifungal index of 1.0%Ce3^＋-TiO2 was（47.0 ± 4.7）%, （82.2 ± 3.5）%, （100 ±0.0）% under indoor weaker light, solar light and black light, respectively. The results of field experiments showed that the antifungal index of 1.0%Ce^3＋-TiO2 was more than that of P-25. The antifungal index of 1.0%Ce^3＋-TiO2 was （81.7 ± 6.5）%, （67.5 ±4.7）%, （38.6±1.9）% for litchi downy blight, maize southern leaf spot, and rice blast, respectively. It was concluded that TiO2 photocatalysis technique should be an effective way for litchi fungal disease control in practice.

关键词： titanium dioxide photocatalytic fungal disease solar light litchi downy blight

Transformation and dissolution of second phases during solution treatment of an Al-Zn-Mg-Cu alloy containing high zinc

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Rare Metals 2018年第5期37卷 376-380页

作者： Kai wen bai-Qing xiong Yun-Qiang Fan Yong-An Zhang Zhi-Hui li xi-Wu li Feng Wang Hong-Wei liu State Key Laboratory of Nonferrous Metals and Processes General Research Institute for Nonferrous MetalsBeijing 100088 China

The transformation and dissolution of Mg（Zn, Cu, Al）2 phase during solution treatment of an Al-Zn-Mg-Cu alloy containing high zinc were investigated by means of optical microscopy （OM）, scanning electron microscopy （SEM）, energy-dispersive X-ray spectrometry （EDX） and X-ray diffraction （XRD）. The results show that solution temperature is the main factor influencing phase dissolution. With solution temperature increasing, the content of residual phases decreases. Phase transformation from Mg（Zn, Cu, Al）2 to S（Al2CuMg） occurs under solution temperature of 450, 460 and 465 ℃. Mg（Zn, Cu, Al）2 phase is directly dissolved into the matrix under solution temperature of 470 and 475 ℃, and no S（Al2CuMg） phase transformed from Mg（Zn, Cu, Al）2 phase is observed. The formation of S（Al2CuMg） phase is mainly controlled by Zn elemental diffusion. The mechanism of transformation and dissolution of second phases was investigated. At low temperature, the dissolution of Zn is faster than that of Mg and Cu, resulting in an appropriate condition to form S（Al2CuMg） phase. At high temperature, the dissolution of main alloying elements has no significant barrier among them to form S（Al2CuMg） phase.

关键词： Al-Zn-Mg-Cu alloy Microstructure Solution treatment Phase transformation

Reduction of arsenic bioavailability by amending seven inorganic materials in arsenic contaminated soil

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Journal of Integrative Agriculture 2015年第7期14卷 1414-1422页

作者： SUN Yuan-yuan liu Rong-le ZENG xi-bai liN Qi-mei bai ling-yu li lian-fang SU Shi-ming WANG Ya-nan Institute of Environment and Sustainable Development in Agriculture Chinese Academy of Agricultural Sciences/Key Laboratory of Agro-EnvironmentMinistry of Agriculture College of Resources and Environmental Sciences China Agricultural University Graduate School of Chinese Academy of Agricultural Sciences

Seven inorganic amendment materials were added into arsenic （As） contaminated soil at a rate of 0.5% （w/w）; the materials used were sepiolite, red mud, iron grit, phosphogypsum, ferrihydrite, iron phosphate, and layered double oxides （LDO）. Plant growth trials using rape （edible rape, Brassia campestris L.） as a bio-indicator are commonly used to assess As bio- availability in soils. In this study, B. campestris was grown in a contaminated soil for 50 days. All of the inorganic amend- ments significantly inhibited the uptake of As by B. campestris. Following soil treatment with the seven aforementioned inorganic ammendments, the As concentrations in the edible parts of B. campestris were reduced by 28.6, 10.5, 8.7, 31.0, 47.4, 25.3, and 28.8%, respectively, as compared with the plants grown in control soil. The most effective amendment was ferdhydrite, which reduced As concentration in B. campestris from 1.84 to 0.97 mg kg-~, compared to control. Furthermore, ferrihydrite-treated soils had a remarkable decrease in both non-specifically sorbed As and available-As by 67 and 20%, respectively, comparing to control. Phosphogypsum was the most cost-effective amendment and it showed excellent performance in reducing the water soluble As in soils by 31% and inhibiting As uptake in B. campestris by 21% comparing to control. Additionally, obvious differences in As transfer rates were observed in the various amendments. The seven amendment materials used in this study all showed potential reduction of As bioavailability and influence on plant growth and other biological processes still need to be further explored in the long term.

关键词： arsenic amendment bioavailability Brassia campestris L.

Inducing Macrophages M2 Polarization by Dexamethasone Laden Mesoporous Silica Nanoparticles from Titanium Implant Surface for Enhanced Osteogenesis

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Acta Metallurgica Sinica(English Letters) 2019年第10期32卷 1253-1260页

作者： Jing Luo xin Ding wen Song Jian-Ying bai Jing liu Zhe li Fan-Hui Meng Fang-Hao Chen Yu-mei Zhang State Key Laboratory of Military Stomatology and National Clinical Research Center for Oral Diseases and Shaanxi Key Laboratory of Oral Diseases Department of Prosthodontics School of Stomatology The Fourth Military Medical University Xi'an 710032 China Department of Stomatology General Hospital of Southern Theater Command of the Chinese People's Liberation Army Guangzhou 510010 China Huaian Stomatological Hospital Huaian 223001 China State Key Laboratory of Military Stomatology and National Clinical Research Center for Oral Diseases and Shaanxi Key Laboratory of Oral Diseases Department of Dental Materials School of Stomatology The Fourth Military Medical University Xi'an 710032 China

The study conveys an idea to enhance the osseointegration of titanium implant (Ti) through modulating macrophages M2 polarization. The ?100 nm spherical mesoporous silica nanoparticles (MSN) that compromised of ~4-nm-diameter nano? tunnels were synthesized by the conventional "sol-gel" method, into which the dexamethasone (DEX) was loaded (DEX@ MSN). The DEX@MSN could consistently release DEX and showed favorable cytocompatibility in RAW264.7 cells. The arginase-1 expression, a specific marker for macrophages M2 polarization, was also enhanced by DEX @ MSN treatment. Then, the Ti was pre-treated with anodization under 5 V to generate the titania nanotubes with ?30 nm diameter (NT-30) and the DEX @ MSN was introduced onto NT-30 surface via electrophoretic deposition, with the aid of chitosan. After optimizing the deposition parameters, the supernatants of RAW264.7 from the decorated implant surface could significantly promote the osteogenic differentiation of murine primary bone marrow mesenchymal stem cells. These findings demonstrate that delivery of DEX from implant surface can modulate the macrophages M2 polarization and result in favorable osteogenesis.

关键词： Macrophages polarization Titanium implant Osteogenesis Dexamethasone Mesoporous silica nanoparticles Electrophoretic deposition