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Seasonal variations in leaf capturing of particulate matter, surface wettability and micromorphology in urban tree species

Huixia WANG, Hui SHI, Yangyang LI, Ya YU, Jun ZHANG

《环境科学与工程前沿（英文）》 2013年 第7卷 第4期   页码 579-588 doi: 10.1007/s11783-013-0524-1

摘要： The seasonal changes in leaf particulate matter (PM) accumulation, surface wettability and micromorphology in urban tree species, including ( . ), ( . ) and ( . ), were studied during a single growing season. The three species showed distinct seasonal trends in PM accumulation, increasing from spring to autumn (or winter) even during the rainy season, but at different rates. During the study, the leaf PM retention amount of , a species with ridged leaf surfaces, was significantly higher than that of and , species with waxy leaf surfaces. The contact angles of water droplets on leaves decreased with leaf age except on the abaxial surface of , which remained non-wettable or highly non-wettable throughout the growing season; the decrease in the contact angle on adaxial surface of was greater when compared with and . A significant and negative relationship existed between leaf PM retention amounts and contact angles on adaxial surface of leaves of all three species. The increase in wettability, probably caused when epicuticular wax was destroyed by mechanical and chemical abrasion, seemed to be the main factor leading to seasonal variations in leaf PM accumulation.

关键词： contact angle     particulate matter     retention amount    

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Modelling the thresholds of nitrogen/phosphorus concentration and hydraulic retention time for bloom

《环境科学与工程前沿（英文）》 2022年 第16卷 第10期 doi: 10.1007/s11783-022-1564-1

摘要：

● A new model for bloom control in open land scape water was constructed.

关键词： Reclaimed water landscape     Algal bloom     Nitrogen and phosphorus     Hydraulic retention time     Threshold     Control model    

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Effects of hydraulic retention time on nitrification activities and population dynamics of a conventional

Hongyan LI, Yu ZHANG, Min YANG, Yoichi KAMAGATA

《环境科学与工程前沿（英文）》 2013年 第7卷 第1期   页码 43-48 doi: 10.1007/s11783-012-0397-8

摘要： The effects of hydraulic retention time (HRT) on the nitrification activities and population dynamics of a conventional activated sludge system fed with synthetic inorganic wastewater were investigated over a period of 260 days. When the HRT was gradually decreased from 30 to 5 h, the specific ammonium-oxidizing rates (SAOR) varied between 0.32 and 0.45 kg (kg mixed liquor suspended solids (MLSS)·d) , and the specific nitrate-forming rates (SNFR) increased from 0.11 to 0.50 kg (kg MLSS·d) , showing that the decrease in HRT led to a significant increase in the nitrite oxidation activity. According to fluorescence in situ hybridization (FISH) analysis results, the proportion of ammonia-oxidizing bacteria (AOBs) among the total bacteria decreased from 33% to 15% with the decrease in HRT, whereas the fraction of nitrite-oxidizing bacteria (NOBs), particularly the fast-growing sp., increased significantly (from 4% to 15% for NOBs and from 1.5% to 10.6% for sp.) with the decrease in HRT, which was in accordance with the changes in SNFR. A short HRT favored the relative growth of NOBs, particularly the fast-growing sp., in the conventional activated sludge system.

关键词： ammonia-oxidizing bacteria     hydraulic retention time     nitrification activity     nitrite-oxidizing bacteria     population dynamics    

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Sustaining health workforce recruitment and retention in township hospitals: a survey on 110 directors

null

《医学前沿（英文）》 2015年 第9卷 第2期   页码 239-250 doi: 10.1007/s11684-015-0392-0

摘要：

Township hospitals, the main provider of rural primary healthcare in China, are severely understaffed. International studies on factors influencing rural working are increasing; however, studies on factors affecting the recruitment and retention of health workers in Chinese township hospitals are limited. The current study aims to understand the motivation of health workers and arrive at a systematic framework of pluralistic factors that would help support health workers in terms of receiving posts and remaining in posts in township hospitals. A three-stage integrated quantitative and qualitative methodology was employed. First, a survey on 120 directors of township hospitals was conducted to learn the latest status of health workers in township hospitals and distinguish existing problems. Second, after sending these problems back to the directors, an open-ended pen-and-paper survey was conducted to ask the directors to identify the factors influencing the attraction and retention of health workers in township hospitals. Third, four focus groups were conducted to gauge the underlying reasons. Five problems from the questionnaire survey were recognized, and numbers of thematic factors were identified at the individual, professional, and treatment environment from the pen-and-paper survey and focus group. Similar to other studies, this framing of both non-financial and financial elements affected the attraction and retention of health workers in township hospitals, thereby filling the gap in a Chinese context. Although several factors had been recognized earlier, our findings further highlighted the importance of these factors. Meanwhile, the factors identified in this study were barely explored in literature. This paper identifies and develops multi-faceted factors to call for a bundled package of multidimensional incentives if decision-makers get interested. The evidence-based findings in our study can be used to provide China-specific policy recommendations on how to recruit and retain health workers in rural areas of China.

关键词： recruitment     retention     health workers     township hospitals     rural regions    

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EFFECT OF EXOGENOUS ADDITIVES ON HEAVY METAL PASSIVATION AND NITROGEN RETENTION IN PIG MANURE COMPOSTING

《农业科学与工程前沿（英文）》 doi: 10.15302/J-FASE-2023487

摘要：

● Research on heavy metal passivation and nitrogen emissions is necessary for the pig industry.

关键词： additives     composting     heavy metals passivation     nitrogen retention     pig manure    

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Bio-based Waterborne Poly(Vanillin-Butyl Acrylate)/MXene Coatings for Leather with Desired Warmth Retention

Jianzhong Ma,Li Ma,Lei Zhang,Wenbo Zhang,Qianqian Fan,Buxing Han,

《工程（英文）》 doi: 10.1016/j.eng.2023.06.005

摘要： This study presents a solvent-free, facile synthesis of a bio-based green antibacterial agent and aromatic monomer methacrylated vanillin (MV) using vanillin. The resulting MV not only imparted antibacterial properties to coatings layered on leather, but could also be employed as a green alternative to petroleum-based carcinogen styrene (St). Herein, MV was copolymerized with butyl acrylate (BA) to obtain waterborne bio-based P(MV–BA) miniemulsion via miniemulsion polymerization. Subsequently, MXene nanosheets with excellent photothermal conversion performance and antibacterial properties, were introduced into the P(MV–BA) miniemulsion by ultrasonic dispersion. During the gradual solidification of P(MV–BA)/MXene nanocomposite miniemulsion on the leather surface, MXene gradually migrated to the surface of leather coatings due to the cavitation effect of ultrasonication and amphiphilicity of MXene, which prompted its full exposure to light and bacteria, exerting the maximum photothermal conversion efficiency and significant antibacterial efficacy. In particular, when the dosage of MXene nanosheets was 1.4 wt%, the surface temperature of P(MV–BA)/MXene nanocomposite miniemulsion-coated leather (PML) increased by about 15 °C in an outdoor environment during winter, and the antibacterial rate against Escherichia coli and Staphylococcus aureus was nearly 100% under the simulated sunlight treatment for 30 min. Moreover, the introduction of MXene nanosheets increased the air permeability, water vapor permeability, and thermal stability of these coatings. This study provides a new insight into the preparation of novel, green, and waterborne bio-based nanocomposite coatings for leather, with desired warmth retention and antibacterial properties. It can not only realize zero-carbon heating based on sunlight in winter, reducing the use of fossil fuels and greenhouse gas emissions, but also improve ability to fight off invasion by harmful bacteria, viruses, and other microorganisms.

关键词： MXene nanosheets     Vanillin     Styrene substitute     Leather coating     Photothermal conversion     Warmth retention     Antibacterial properties    

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Influence of hydraulic retention time on behavior of antibiotics and antibiotic resistance genes in aerobic

Jie Liao, Chaoxiang Liu, Lin Liu, Jie Li, Hongyong Fan, Jiaqi Ye, Zhichao Zeng

《环境科学与工程前沿（英文）》 2019年 第13卷 第3期 doi: 10.1007/s11783-019-1115-6

摘要：

Longer HRT can enhance degradation rate of sulfamethoxazole in granular reactor.

Longer HRT can reduce accumulated concentrations of TCs and QNs in sludge.

Longer HRT may have increased relative abundances of ARGs in aerobic granules.

关键词： Aerobic granules     Swine wastewater     Tetracyclines     Fluoroquinolones     Sulfonamides    

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A novel approach to preparing ultra-lightweight ceramsite with a large amount of fly ash

Sen Liu, Congren Yang, Wei Liu, Longsheng Yi, Wenqing Qin

《环境科学与工程前沿（英文）》 2020年 第14卷 第4期 doi: 10.1007/s11783-020-1241-1

摘要： •Ultra-lightweight ceramsite is prepared with 80% fly ash. •SiO2, Al2O3, and flux contents significantly influence the performance of ceramsite. •The expansion of ceramsite is caused by the formation of a dense glaze and gas. •The bulk density of ultra-lightweight ceramsite is only 340 kg/m3. The disposal of fly ash has become a serious problem in China due to its rapid increase in volume in recent years. The most common method of fly ash disposal is solidification-stabilization-landfill, and the most common reuse is low-value-added building materials. A novel processing method for preparing ultra-lightweight ceramsite with fly ash was developed. The results show that the optimal parameters for preparation of ultra-lightweight ceramsite are as follows: mass ratio of fly ash:kaolin:diatomite= 80:15:5, preheating temperature of 800°C, preheating time of 5 min, sintering temperature of 1220°C, and sintering time of 10 min. The expansion agent is perlite, at 10 wt.% addition. Finally, a ceramsite with bulk density of 340 kg/m3, particle density of 0.68 g/cm3, and cylinder compressive strength of 1.02 MPa was obtained. Because of its low density and high porosity, ultra-lightweight ceramsite has excellent thermal insulation performance, and its strength is generally low, so it is usually used in the production of thermal insulation concrete and its products. The formation of a liquid-phase component on the surface, and generation of a gas phase inside ceramsite during the sintering process, make it possible to control the production of the suitable liquid phase and gas in this system, resulting in an optimization of the expansion behavior and microstructure of ceramsite. These characteristics show the feasibility of industrial applications of fly ash for the production of ultra-lightweight ceramsite, which could not only produce economic benefits, but also conserve land resources and protect the environment.

关键词： Fly ash     Ultra-lightweight ceramsite     Expansion mechanism     Sintering process    

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Effects of hydraulic retention time on net present value and performance in a membrane bioreactor treating

Dawei Yu, Jianxing Wang, Libin Zheng, Qianwen Sui, Hui Zhong, Meixue Cheng, Yuansong Wei

《环境科学与工程前沿（英文）》 2020年 第14卷 第6期 doi: 10.1007/s11783-020-1280-7

摘要： Abstract • The membrane bioreactor cost decreased by 38.2% by decreasing HRT from 72 h to 36 h. • Capital and operation costs contributed 62.1% and 37.9% to decreased costs. • The membrane bioreactor is 32.6% cheaper than the oxidation ditch for treatment. • The effluent COD also improved from 709.93±62.75 mg/L to 280±17.32 mg/L. • Further treatment also benefited from lower pretreatment investment. A cost sensitivity analysis was performed for an industrial membrane bioreactor to quantify the effects of hydraulic retention times and related operational parameters on cost. Different hydraulic retention times (72–24 h) were subjected to a flat-sheet membrane bioreactor updated from an existing 72 h oxidation ditch treating antibiotic production wastewater. Field experimental data from the membrane bioreactor, both full-scale (500 m3/d) and pilot (1.0 m3/d), were used to calculate the net present value (NPV), incorporating both capital expenditure (CAPEX) and operating expenditure. The results showed that the tank cost was estimated above membrane cost in the membrane bioreactor. The decreased hydraulic retention time from 72 to 36 h reduced the NPV by 38.2%, where capital expenditure contributed 24.2% more than operational expenditure. Tank construction cost was decisive in determining the net present value contributed 62.1% to the capital expenditure. The membrane bioreactor has the advantage of a longer lifespan flat-sheet membrane, while flux decline was tolerable. The antibiotics decreased to 1.87±0.33 mg/L in the MBR effluent. The upgrade to the membrane bioreactor also benefited further treatments by 10.1%–44.7% lower direct investment.

关键词： Antibiotic production wastewater     Net present value     Membrane bioreactor     Hydraulic retention time     Pollutant removal    

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Optimizing environmental insulation thickness of buildings with CHP-based district heating system based on amount

Yumei ZHANG, Pengfei JIE, Chunhua LIU, Jing LI

《能源前沿（英文）》 2022年 第16卷 第4期   页码 613-628 doi: 10.1007/s11708-020-0700-5

摘要： The increase of insulation thickness (IT) results in the decrease of the heat demand and heat medium temperature. A mathematical model on the optimum environmental insulation thickness (OEIT) for minimizing the annual total environmental impact was established based on the amount of energy and energy grade reduction. Besides, a case study was conducted based on a residential community with a combined heat and power (CHP)-based district heating system (DHS) in Tianjin, China. Moreover, the effect of IT on heat demand, heat medium temperature, exhaust heat, extracted heat, coal consumption, carbon dioxide (CO ) emissions and sulfur dioxide (SO ) emissions as well as the effect of three types of insulation materials (i.e., expanded polystyrene, rock wool and glass wool) on the OEIT and minimum annual total environmental impact were studied. The results reveal that the optimization model can be used to determine the OEIT. When the OEIT of expanded polystyrene, rock wool and glass wool is used, the annual total environmental impact can be reduced by 84.563%, 83.211%, and 86.104%, respectively. It can be found that glass wool is more beneficial to the environment compared with expanded polystyrene and rock wool.

关键词： optimum environmental insulation thickness     heat medium temperature     energy grade     extracted heat     exhaust heat    

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Cotransfecting norepinephrine transporter and vesicular monoamine transporter 2 genes for increased retention

null

《医学前沿（英文）》 2017年 第11卷 第1期   页码 120-128 doi: 10.1007/s11684-017-0501-3

摘要：

Norepinephrine transporter (NET) transfection leads to significant uptake of iodine-131-labeled metaiodobenzylguanidine (131I-MIBG) in non-neuroendocrine tumors. However, the use of 131I-MIBG is limited by its short retention time in target cells. To prolong the retention of 131I-MIBG in target cells, we infected hepatocarcinoma (HepG2) cells with Lentivirus-encoding human NET and vesicular monoamine transporter 2 (VMAT2) genes to obtain NET-expressing, NET-VMAT2-coexpressing, and negative-control cell lines. We evaluated the uptake and efflux of 131I-MIBG both in vitro and in vivo in mice bearing transfected tumors. NET-expressing and NET-VMAT2-coexpressing cells respectively showed 2.24 and 2.22 times higher 131I-MIBG uptake than controls. Two hours after removal of 131I-MIBG-containing medium, 25.4% efflux was observed in NET-VMAT2-coexpressing cells and 38.6% in NET-expressing cells. In vivo experiments were performed in nude mice bearing transfected tumors; results revealed that NET-VMAT2-coexpressing tumors had longer 131I-MIBG retention time than NET-expressing tumors. Meanwhile, NET-VMAT2-coexpressing and NET-expressing tumors displayed 0.54% and 0.19%, respectively, of the injected dose per gram of tissue 24 h after 131I-MIBG administration. Cotransfection of HepG2 cells with NET and VMAT2resulted in increased 131I-MIBG uptake and retention. However, the degree of increase was insufficient to be therapeutically effective in target cells.

关键词： norepinephrine transporter     vesicular monoamine transporter 2     -MIBG     gene therapy     lentivirus vector    

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Effect of biochar amendment on soil’s retention capacity for estrogenic hormones from poultry manure

Sukhjot MANN, Zhiming QI, Shiv O. PRASHER, Lanhai LI, Dongwei GUI, Qianjing JIANG

《农业科学与工程前沿（英文）》 2017年 第4卷 第2期   页码 208-219 doi: 10.15302/J-FASE-2017138

摘要： Most animals, including humans, produce natural sex hormones such as estrogens: 17β-estradiol (E2) and estrone (E1). These compounds are able to disrupt the reproductive systems of living organisms at trace concentrations (ng·L ). This experiment tests the hypothesis that 1% slow pyrolysis biochar-amended sandy soil could retain significant amount of estrogens (E1, E2) from poultry manure in its second year of application. The experiment was conducted over 46 days and consisted of a series of lysimeters containing sandy soil with biochar-amended topsoil. The application rate of poultry manure was kept at 2.47 kg·m . The biochar held a significant concentration of hormone during the first year of its application. However, in the following year (current study), there was no significant retention of hormones in the biochar-amended soil. During the first year after application, the biochar was fresh, so its pores were available for hydrophobic interactions and held significant concentration of hormones. As time passed there were several biotic and abiotic changes on the surface of the biochar so that after some physical fragmentation, pores on the surface were no longer available for hydrophobic interactions. The biochar started releasing dissolved organic carbon, which facilitated greater mobility of hormones from poultry manure down the soil profile.

关键词： adsorption     degradation     dissolved organic carbon     17β-estradiol (E2)     estrone (E1)    

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Nitrogen-retaining property of compost in an aerobic thermophilic composting reactor for the sanitary disposal of human feces

Fan BAI, Xiaochang WANG,

《环境科学与工程前沿（英文）》 2010年 第4卷 第2期   页码 228-234 doi: 10.1007/s11783-010-0022-7

摘要： Aerobic composting is a method for the sanitary disposal of human feces as is used in bio-toilet systems. As the products of composting can be utilized as a fertilizer, it would be beneficial if the composting conditions could be more precisely controlled for the retention of fecal nitrogen as long as possible in the compost. In this study, batch experiments were conducted using a closed aerobic thermophilic composting reactor with sawdust as the bulk matrix to simulate the condition of a bio-toilet for the sanitary disposal of human feces. Attention was paid to the characteristics of nitrogen transformation. Under the controlled conditions of temperature at 60°C, moisture content at 60%, and a continuous air supply, more than 70% fecal organic removal was obtained, while merely 17% fecal nitrogen loss was observed over a two-week composting period. The nitrogen loss was found to occur mainly in the first 24 h with the rapid depletion of inorganic nitrogen but with an almost unchanged organic nitrogen content. The fecal NH–N which was the main component of the inorganic nitrogen (>90%) decreased rapidly in the first day, decreased at a slower rate over the following days, and finally disappeared entirely. The depletion of NH–N was accompanied by the accumulation of NH gas in the ammonia absorber connected to the reactor. A mass balance between the exhausted NH gas and the fecal NH–N content in the first 24 hours indicated that the conversion of ammonium into gaseous ammonia was the main reason for nitrogen loss. Thermophilic composting could be considered as a way to keep a high organic nitrogen content in the compost for better utilization as a fertilizer.

关键词： nitrogen retention     composting reactor     human feces     aerobic     thermophilic     fertilizer    

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聚羧酸系减水剂在客运专线工程中的应用研究

黄直久

《中国工程科学》 2009年 第11卷 第1期   页码 75-80

摘要：

介绍聚羧酸系减水剂在满足铁路客运专线高性能混凝土综合性能方面的能力和特点，分析了工程应用中使用聚羧酸系减水剂存在的一些问题。提出解决聚羧酸系减水剂与水泥的相容性问题以及保持聚羧酸系减水剂本身质量稳定性是目前该减水剂应用的关键。

关键词： 聚羧酸系减水剂     水泥的相容性     质量稳定性     高性能混凝土    

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Effects of operating conditions on membrane charge property and nanofiltration

Li XU, Li-Shun DU, Jing HE

《化学科学与工程前沿（英文）》 2011年 第5卷 第4期   页码 492-499 doi: 10.1007/s11705-011-1143-7

摘要： The effects of the operating pressure, cross flow velocity, feed concentration, and temperature on the streaming and Zeta potential of the membranes were studied. The permeate flux and the retention rate under different nanofiltration operating conditions were also investigated. The results show that the higher pressure, feed concentration, temperature, and lower cross flow velocity lead to the higher absolute value of streaming and Zeta potential. The permeate flux of the nanofiltration decreases with the feed concentration and increases with not only the pressure but also the cross flow velocity and temperature. The higher the pressure and the cross flow velocity, the higher the retention rate. The lower feed concentration and higher temperature leads to lower retention rate. The effects of the operating conditions on the permeate flux and the retention rate were explained by the variation of the membrane charge property.

关键词： nanofiltration membrane     streaming potential     Zeta potential     permeate flux     retention rate    

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标题 作者 时间 类型 操作

Seasonal variations in leaf capturing of particulate matter, surface wettability and micromorphology in urban tree species

Huixia WANG, Hui SHI, Yangyang LI, Ya YU, Jun ZHANG

期刊论文

Modelling the thresholds of nitrogen/phosphorus concentration and hydraulic retention time for bloom

期刊论文

Effects of hydraulic retention time on nitrification activities and population dynamics of a conventional

Hongyan LI, Yu ZHANG, Min YANG, Yoichi KAMAGATA

期刊论文

Sustaining health workforce recruitment and retention in township hospitals: a survey on 110 directors

null

期刊论文

EFFECT OF EXOGENOUS ADDITIVES ON HEAVY METAL PASSIVATION AND NITROGEN RETENTION IN PIG MANURE COMPOSTING

期刊论文

Bio-based Waterborne Poly(Vanillin-Butyl Acrylate)/MXene Coatings for Leather with Desired Warmth Retention

Jianzhong Ma,Li Ma,Lei Zhang,Wenbo Zhang,Qianqian Fan,Buxing Han,

期刊论文

Influence of hydraulic retention time on behavior of antibiotics and antibiotic resistance genes in aerobic

Jie Liao, Chaoxiang Liu, Lin Liu, Jie Li, Hongyong Fan, Jiaqi Ye, Zhichao Zeng

期刊论文

A novel approach to preparing ultra-lightweight ceramsite with a large amount of fly ash

Sen Liu, Congren Yang, Wei Liu, Longsheng Yi, Wenqing Qin

期刊论文

Effects of hydraulic retention time on net present value and performance in a membrane bioreactor treating

Dawei Yu, Jianxing Wang, Libin Zheng, Qianwen Sui, Hui Zhong, Meixue Cheng, Yuansong Wei

期刊论文

Optimizing environmental insulation thickness of buildings with CHP-based district heating system based on amount

Yumei ZHANG, Pengfei JIE, Chunhua LIU, Jing LI

期刊论文

Cotransfecting norepinephrine transporter and vesicular monoamine transporter 2 genes for increased retention

null

期刊论文

Effect of biochar amendment on soil’s retention capacity for estrogenic hormones from poultry manure

Sukhjot MANN, Zhiming QI, Shiv O. PRASHER, Lanhai LI, Dongwei GUI, Qianjing JIANG

期刊论文

Nitrogen-retaining property of compost in an aerobic thermophilic composting reactor for the sanitary disposal of human feces

Fan BAI, Xiaochang WANG,

期刊论文

聚羧酸系减水剂在客运专线工程中的应用研究

黄直久

期刊论文

Effects of operating conditions on membrane charge property and nanofiltration

Li XU, Li-Shun DU, Jing HE

期刊论文