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Seasonal and treatment-process variations in invertebrates in drinking water treatment plants

Zhiling Wu, Xianchun Tang, Hongbin Chen

《环境科学与工程前沿（英文）》 2021年 第15卷 第4期 doi: 10.1007/s11783-020-1354-6

摘要： Abstract • Seasonal and treatment-process variations in invertebrates in a DWTP were analyzed. • The propagation and leakage of invertebrates in BAC filter were the most serious. • Invertebrates can survive and reproduce in chlorine disinfected clear water tanks. • Proportions of endogenous invertebrates increased along the treatment process. Problems associated with excessive propagation and leakage of invertebrates in drinking water have received increasing attention in recent years. We performed a monthly survey of invertebrate abundance and taxa in the effluent of each treatment stage in a drinking water treatment plant between May 2015 and April 2016 and analyzed seasonal and treatment-process variations in invertebrates. The results showed that invertebrate abundances in raw water, effluent of the biological activated carbon (BAC) filter, and finished water significantly correlated with water temperature, whereas no correlation was observed between water temperature and invertebrate abundance in the effluents of the sedimentation tank and sand filter. The dominant taxa in the effluent of each treatment stage were rotifers, nematodes, and crustaceans. The sedimentation tank could efficiently remove invertebrates with an annual average removal rate of 92%. The propagation and leakage of invertebrates occurred in the sand and BAC filters but more seriously in the latter. The average reproduction rate in the BAC filter was 268.8% with rotifers as the taxon that leaked the most. Invertebrate survival and reproduction were also observed in the chlorine-disinfected clean water reservoir with an average reproduction rate of 41.9%. Owing to differences in chlorine resistance, the reproduction ability of the dominant taxa was in the order nematodes>crustaceans>rotifers. The proportion of endogenous invertebrates gradually increased along the treatment process. The average proportion of endogenous invertebrates in the finished water was higher than 79.0%. Our findings suggested that waterworks should pay more attention to endogenous invertebrate growth.

关键词： Invertebrates     Drinking water     Seasonal variations     Treatment process    

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Seasonal variations of transport pathways andpotential sources of PM

Yuan Chen, Shaodong Xie, Bin Luo

《环境科学与工程前沿（英文）》 2018年 第12卷 第1期 doi: 10.1007/s11783-018-1009-z

摘要： Seasonal pattern of transport pathways and potential sourcesof PM in Chengdu during 2012–2013were investigated based on hourly PM data,backward trajectories, clustering analysis, potential source contributionfunction (PSCF), and concentration-weighted trajectory (CWT) method.The annual hourly mean PM concentrationin Chengdu was 97.4 mg·m . 5, 5, 5 and 3 mean clusters were generatedin four seasons, respectively. Short-distance air masses, which travelledwithin the Sichuan Basin with no specific source direction and relativelyhigh PM loadings (>80 mg·m ) appearedas important pathways in all seasons. These short pathways indicatedthat emissions from both local and surrounding regions of Chengducontributed significantly to PM pollution.The cities in southern Chengdu were major potential sources with PSCF>0.6and CWT>90 mg·m . The northeastern pathway prevailed throughoutthe year with higher frequency in autumn and winter and lower frequencyin spring and summer. In spring, long-range transport from southernXinjiang was a representative dust invasion path to Chengdu, and theCWT values along the path were 30-60 mg·m . Long-range transportwas also observed in autumn from southeastern Xinjiang along a northwesterlypathway, and in winter from the Tibetan Plateau along a westerly pathway.In summer, the potential source regions of Chengdu were smaller thanthose in other seasons, and no long-range transport pathway was observed.Results of PSCF and CWT indicated that regions in Qinghai and Tibetcontributed to PM pollution in Chengdu aswell, and their CWT values increased to above 30 mg·m in winter.

关键词： Transport pathway     Backwardtrajectory     Clustering analysis     Potential source     Chengdu    

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Spatial and seasonal variations in bacterial communities of the Yellow Sea by T-RFLP analysis

Hongyuan WANG, Xiaolu JIANG, Ya HE, Huashi GUAN

《环境科学与工程前沿（英文）》 2009年 第3卷 第2期   页码 194-199 doi: 10.1007/s11783-009-0018-3

摘要： Four typical coastal sites (rocky shore, sandy shore, mud flat shore, and artificial harbor) at the Yellow Sea were chosen to investigate the spatial and seasonal variations in bacterial communities. This was accomplished by using terminal restriction fragment length polymorphism (T-RFLP) analysis of PCR amplified 16S rDNA fragments. Two kinds of tetrameric restriction enzymes, I and I, were used in the experiment to depict the bacterial community diversity in different marine environments. It was found that the community compositions digested by the two enzymes separately were different. However, the results of bacterial community diversity derived from them were similar. The MDA analysis results of T-RFLP profiles coming from I and I both exhibited a significant seasonal community shift for bacteria and a relatively low spatial variation among the four locations. With I as the sample, the pair wise -tests also revealed that variations were minor between each pair of marine environments, with ranging from 0.198 to 0.349. However, the bacterial community structure in the mud flat site depicted a larger difference than each of the other three sites ( ranging from 0.282 to 0.349).

关键词： terminal restriction fragment length polymorphism (T-RFLP)     bacterial community structure     marine microbial diversity     HhaI     MspI    

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

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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A 14-year measurement of toxic elements in atmospheric particulates in Hong Kong from 1995 to 2008

Wei NIE,Tao WANG,Aijun DING,Xuehua ZHOU,Wenxing WANG

《环境科学与工程前沿（英文）》 2014年 第8卷 第4期   页码 553-560 doi: 10.1007/s11783-013-0523-2

摘要： Toxic elements in the atmosphere can enter and accumulate in the human body, seriously impacting human health. In this study, we analyzed a 14-year (1995–2008) measurement of three toxic elements (As, Cd and Cr) in PM in Hong Kong, China. The pollution of these toxic elements in Hong Kong was not serious. The trend analysis showed that As and Cr in PM increased at a statistically significant level ( <0.05) during the 14-year period, while the Cd in PM did not change significantly. Typical seasonal variations were observed for all three toxic elements, largely in relation to the Asian monsoon. Hourly 10-day backward trajectories were computed and categorised into four groups. The continental air masses showed much higher concentrations of the three toxic elements than the marine air masses. The abundances of As and Cd in the PM were much higher in the continental air masses than those in the marine air masses, while the abundances of Cr showed an opposite pattern. The trends of the three toxic elements in East China’s air mass were consistent with those in the overall data set of Hong Kong. Examination of the toxic element data recorded at urban sites and a roadside site also indicated a large contribution of external air masses to particulate As and Cd in Hong Kong. These results suggest that the long-range transport from the mainland of China is the dominant contributor to particulate As and Cd, while both local and long-distance sources determine the particulate Cr in Hong Kong.

关键词： toxic elements     increasing trends     seasonal variations     air masses     long-distance sources    

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Optimization for operating modes based on simulation of seasonal underground thermal energy storage

ZHAO Jun, CHEN Yan, LI Xinguo

《能源前沿（英文）》 2008年 第2卷 第3期   页码 298-301 doi: 10.1007/s11708-008-0053-y

摘要： A simulation was performed, which concerned the feasibility of seasonal underground thermal energy storage (UTES) in Tianjin, China. The investigated system consisted of 8 boreholes. In summer, residual solar thermal energy was emitted into the soil surrounding the borehole heat exchangers through which the stored energy was extracted in winter with a ground coupled heat pump (GCHP) to provide a proper heating temperature. A simulation study was performed to study the influence of system operation modes on thermal recovery based on the experimental data of a GCHP system, local meteorological conditions and soil properties in Tianjin. The results indicate a thermal recovery ratio of less than 67% and different temperature distributions under three modes. Finally, an operation mode was suggested based on both lower loss and better thermal recovery in the UTES.
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Effects of sulfur on variations in the chemical speciation of heavy metals from fly ash glass

《环境科学与工程前沿（英文）》 2023年 第17卷 第10期 doi: 10.1007/s11783-023-1728-7

摘要：

● A higher sulfur content reduced the curing rate of Cr in glass.

关键词： Dechlorinated fly ash     SO3     Heavy metal     Chemical speciation     Glass solidification    

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Genomic variations in the counterpart normal controls of lung squamous cell carcinomas

null

《医学前沿（英文）》 2018年 第12卷 第3期   页码 280-288 doi: 10.1007/s11684-017-0580-1

摘要：

Lung squamous cell carcinoma (LUSC) causes approximately 400 000 deaths each year worldwide. The occurrence of LUSC is attributed to exposure to cigarette smoke, which induces the development of numerous genomic abnormalities. However, few studies have investigated the genomic variations that occur only in normal tissues that have been similarly exposed to tobacco smoke as tumor tissues. In this study, we sequenced the whole genomes of three normal lung tissue samples and their paired adjacent squamous cell carcinomas. We then called genomic variations specific to the normal lung tissues through filtering the genomic sequence of the normal lung tissues against that of the paired tumors, the reference human genome, the dbSNP138 common germline variants, and the variations derived from sequencing artifacts. To expand these observations, the whole exome sequences of 478 counterpart normal controls (CNCs) and paired LUSCs of The Cancer Genome Atlas (TCGA) dataset were analyzed. Sixteen genomic variations were called in the three normal lung tissues. These variations were confirmed by Sanger capillary sequencing. A mean of 0.5661 exonic variations/Mb and 7.7887 altered genes per sample were identified in the CNC genome sequences of TCGA. In these CNCs, C:G→T:A transitions, which are the genomic signatures of tobacco carcinogen N-methyl-N-nitro-N-nitrosoguanidine, were the predominant nucleotide changes. Twenty five genes in CNCs had a variation rate that exceeded 2%, including ARSD (18.62%), MUC4 (8.79%), and RBMX (7.11%). CNC variations in CTAGE5 and USP17L7 were associated with the poor prognosis of patients with LUSC. Our results uncovered previously unreported genomic variations in CNCs, rather than LUSCs, that may be involved in the development of LUSC.

关键词： lung cancer     counterpart normal control     genomic variations    

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Numerical simulation of underground seasonal cold energy storage for a 10 MW solar thermal power plant

Zulkarnain ABBAS, Yong LI, Ruzhu WANG

《能源前沿（英文）》 2021年 第15卷 第2期   页码 328-344 doi: 10.1007/s11708-020-0676-1

摘要： This paper aims to explore an efficient, cost-effective, and water-saving seasonal cold energy storage technique based on borehole heat exchangers to cool the condenser water in a 10 MW solar thermal power plant. The proposed seasonal cooling mechanism is designed for the areas under typical weather conditions to utilize the low ambient temperature during the winter season and to store cold energy. The main objective of this paper is to utilize the storage unit in the peak summer months to cool the condenser water and to replace the dry cooling system. Using the simulation platform transient system simulation program (TRNSYS), the borehole thermal energy storage (BTES) system model has been developed and the dynamic capacity of the system in the charging and discharging mode of cold energy for one-year operation is studied. The typical meteorological year (TMY) data of Dunhuang, Gansu province, in north-western China, is utilized to determine the lowest ambient temperature and operation time of the system to store cold energy. The proposed seasonal cooling system is capable of enhancing the efficiency of a solar thermal power plant up to 1.54% and 2.74% in comparison with the water-cooled condenser system and air-cooled condenser system respectively. The techno-economic assessment of the proposed technique also supports its integration with the condenser unit in the solar thermal power plant. This technique has also a great potential to save the water in desert areas.

关键词： seasonal cold energy storage     borehole heat exchangers     typical meteorological data     TRNSYS     condenser cooling     techno-economic assessment    

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Bioaerosol emissions variations in large-scale landfill region and their health risk impacts

《环境科学与工程前沿（英文）》 2022年 第16卷 第12期 doi: 10.1007/s11783-022-1593-9

摘要：

● The airborne bacteria in landfills were 4–50 times higher than fungi.

关键词： Microbial aerosols     Landfill sites     Health risk assessment     CALPUFF    

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Investigations on color variations of Morpho rhetenor butterfly wing scales

Guanglan LIAO, Haibo ZUO, Xuan JIANG, Xuefeng YANG, Tielin SHI

《机械工程前沿（英文）》 2012年 第7卷 第4期   页码 394-400 doi: 10.1007/s11465-012-0347-y

摘要：

Experiments and simulations are carried out to investigate the optical properties of butterfly wing scales. The upper surface of a male butterfly wing presents a single-layer of scales, the microstructures of which are responsible for the brilliant blue color. The color varies from cyan blue to yellow green and soon afterwards returns back to cyan blue when some ethanol is dropped on the upper surface. At the start of the ethanol volatilization process, the reflection spectrum remains stable. As the ethanol further volatilizes, the peak reflectance decreases slightly, then increases dramatically. Meanwhile, the peak wavelength keeps approximately constant, then decreases, and keeps almost stable at the end of the process. Therefore, the optical properties depend strongly on the varying ambient conditions, including the refractive index and the thickness of the packing medium. Moreover, the possible causes for the scales in dark green region after several dropping ethanol experiments are clarified. This research benefits our understanding of the color variation mechanisms of the wing scales, and provides inspiration for further studies and applications.

关键词： Morpho rhetenor     microstructures     color variations     ambient medium    

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Spatio-temporal variations of water quality in Yuqiao Reservoir Basin, North China

Yuan XU,Ruqin XIE,Yuqiu WANG,Jian SHA

《环境科学与工程前沿（英文）》 2015年 第9卷 第4期   页码 649-664 doi: 10.1007/s11783-014-0702-9

摘要： Fuzzy comprehensive assessment and multivariate statistical techniques including cluster analysis, discriminant analysis, principal component analysis, and factor analysis were applied to analyze the water quality status of Yuqiao Reservoir Basin, North China, for assessing its spatio-temporal variations and identifying potential pollution sources. In this paper, we considered data for 14 water quality parameters collected during 1990–2004 at 7 water quality monitoring sites. The results of fuzzy comprehensive assessment revealed that water quality in Yuqiao Reservoir Basin showed a downtrend from 1990 to 2001 with fluctuation, and a slowly upward trend after 2001. The major water quality belonged to Class III and IV. Besides, hierarchical cluster analysis divided 7 monitoring sites into two groups (Group A and B), and 12 months into three periods (low-flow (LF), normal-flow (NF), and high-flow (HF) period). Temp, pH, SS, T-har, DO, NO -N and TP were identified as significant variables affecting spatial variations, and Temp, pH and NO -N were identified as significant variables affecting temporal variations by discriminant analysis. Factor analysis identified four latent pollution sources for water quality variations: nutrient pollution, organic pollution, inorganic pollution, and natural pollution. Moreover, for Group A regions, pollution inputs mainly came from domestic wastewater and industrial sewage. For Group B regions, it is more likely that water pollution resulted from the combined effects of domestic wastewater, hospital wastewater, agriculture runoff, and fishpond discharge, as well as the incoming water from upstream.

关键词： Fuzzy comprehensive assessment     multivariate statistical analysis     water quality    

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Robust design approach to the minimization of functional performance variations of products and systems

J. ZHANG, H. DU, D. XUE, P. GU

《机械工程前沿（英文）》 2021年 第16卷 第2期   页码 379-392 doi: 10.1007/s11465-020-0607-1

摘要： Functional performance variations of products and systems are often used to measure the qualities of products and systems considering the changes in the design parameter values caused by uncertainties. A robust design approach has been developed in this research to minimize the functional performance variations considering the design parameter uncertainties by identifying the boundaries of the functional performance variations through optimization. In this work, a mathematical model is developed to describe the relationships among functional performance, design configurations and parameters, and design parameter uncertainties. A multi-level optimization model is established to identify: (1) The optimal design configuration, (2) the optimal values of design parameters, and (3) the boundaries of functional performance variations. Sensitivity analysis considering the impact of parameter uncertainties on functional performance variation boundaries has also been conducted. A case study on the design of a truss system has been conducted. Case study results show that the sensitivities of functional performance variation boundaries to the design parameter uncertainties can be reduced significantly using the new robust design approach.

关键词： product design     robust design     design optimization     uncertainties    

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Seasonal variation of nitrogen and phosphorus in Xiaojiang River—A tributary of the Three Gorges Reservoir

Zhe LI , Jinsong GUO , Man LONG , Fang FANG , Jinping SHENG , Hong ZHOU ,

《环境科学与工程前沿（英文）》 2009年 第3卷 第3期   页码 334-340 doi: 10.1007/s11783-009-0039-y

摘要： A yearlong monitoring program in the backwater area of Xiaojiang River (XBA) was launched in order to investigate the eutrophication of backwater areas in tributaries of the Yangtze River in the Three Gorges Reservoir (TGR) in China, starting after the impoundment water level of the TGR reached 156 m. From March 2007 to March 2008, the average concentration of total nitrogen (TN) and total phosphorus (TP) were (1553 ± 484) μg·L and (62 ± 31) μg·L, respectively. The mean value of chlorophyll was (9.07 ± 0.91) μg·L. The trophic level of XBA was meso-eutrophic, while the general nutrient limitation was phosphorus. The results indicated that XBA has a strong ability to purify itself and has non-point source pollution from terrestrial runoff. The variation of TN/TP ratio was caused by a variation in TN rather than in TP when TN/TP<22. N-fixation from cyanobacteria occurred and became an important process in overcoming the nitrogen deficit under a low TN/TP ratio. When TN/TP ≥ 22, the variation of TP affected the TN/TP ratio more significantly than TN. The increase of TP in XBA was caused mainly by particulate phosphorus, which could originate from a non-point source as adsorptive inorganic forms after heavy rainfall and surface runoff. An increase in the river’s flow could also contribute to an unstable environment for the growth of phytoplankton.

关键词： Three Gorges Reservoir     eutrophication     nitrogen     phosphorus     seasonal variation     chlorophyll    

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Genotype variations in accumulation of cadmium and lead in celery (

Kun ZHANG, Jianbing WANG, Zhongyi YANG, Guorong XIN, Jiangang YUAN, Junliang XIN, Charlie HUANG

《环境科学与工程前沿（英文）》 2013年 第7卷 第1期   页码 85-96 doi: 10.1007/s11783-012-0399-3

摘要： To help reduce risks of heavy metal pollution, two pot experiments were conducted to investigate the variations, transfer potential, and stability of Cadmium (Cd) and Lead (Pb) accumulations in celery ( L.) and to screen for low Cd and Pb accumulative cultivars. The maximum differences in shoot Cd concentration were 4.7-fold under low-Cd exposure and 3.3-fold under high-Cd exposure. These genotype variations in Cd accumulation are sufficiently large to help reduce Cd contamination risk in soil by using the Low-Cd-Accumulative genotypes. Cd accumulation of the Low-Cd-Accumulative genotypes is significantly positive correlated with Pb accumulation. Evidence obtained proves that Cd and Pb accumulations in celery are stable and genotype-dependent at the cultivar level. The presence of high-Pb contamination in soil promoted Cd accumulation in shoots of celery. Celery is considered a species with high risks in Cd pollution and low risks in Pb pollution. Among the tested cultivars, cv. Shuanggangkangbing (SGKB) had the lowest shoot Cd and Pb accumulating abilities, and thus is the most important material for breeding of pollution-safe cultivars (PSCs) to minimize Cd and Pb accumulations in celery.

关键词： cadmium (Cd) accumulation     lead (Pb) accumulation     celery     genotype variation     food safety    

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标题 作者 时间 类型 操作

Seasonal and treatment-process variations in invertebrates in drinking water treatment plants

Zhiling Wu, Xianchun Tang, Hongbin Chen

期刊论文

Seasonal variations of transport pathways andpotential sources of PM

Yuan Chen, Shaodong Xie, Bin Luo

期刊论文

Spatial and seasonal variations in bacterial communities of the Yellow Sea by T-RFLP analysis

Hongyuan WANG, Xiaolu JIANG, Ya HE, Huashi GUAN

期刊论文

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

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

期刊论文

A 14-year measurement of toxic elements in atmospheric particulates in Hong Kong from 1995 to 2008

Wei NIE,Tao WANG,Aijun DING,Xuehua ZHOU,Wenxing WANG

期刊论文

Optimization for operating modes based on simulation of seasonal underground thermal energy storage

ZHAO Jun, CHEN Yan, LI Xinguo

期刊论文

Effects of sulfur on variations in the chemical speciation of heavy metals from fly ash glass

期刊论文

Genomic variations in the counterpart normal controls of lung squamous cell carcinomas

null

期刊论文

Numerical simulation of underground seasonal cold energy storage for a 10 MW solar thermal power plant

Zulkarnain ABBAS, Yong LI, Ruzhu WANG

期刊论文

Bioaerosol emissions variations in large-scale landfill region and their health risk impacts

期刊论文

Investigations on color variations of Morpho rhetenor butterfly wing scales

Guanglan LIAO, Haibo ZUO, Xuan JIANG, Xuefeng YANG, Tielin SHI

期刊论文

Spatio-temporal variations of water quality in Yuqiao Reservoir Basin, North China

Yuan XU,Ruqin XIE,Yuqiu WANG,Jian SHA

期刊论文

Robust design approach to the minimization of functional performance variations of products and systems

J. ZHANG, H. DU, D. XUE, P. GU

期刊论文

Seasonal variation of nitrogen and phosphorus in Xiaojiang River—A tributary of the Three Gorges Reservoir

Zhe LI , Jinsong GUO , Man LONG , Fang FANG , Jinping SHENG , Hong ZHOU ,

期刊论文

Genotype variations in accumulation of cadmium and lead in celery (

Kun ZHANG, Jianbing WANG, Zhongyi YANG, Guorong XIN, Jiangang YUAN, Junliang XIN, Charlie HUANG

期刊论文