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Relationship between heavy metal concentrations of herbaceous plants and soils at four Pb-Zn mining sites in Yunnan, China

Yuan LI , Yanqun ZU , Qixian FANG , Zhaohua GAO , Christian SCHVARTZ ,

《环境科学与工程前沿（英文）》 2009年 第3卷 第3期   页码 325-333 doi: 10.1007/s11783-009-0024-5

摘要： This paper studied the relationship between heavy metal concentrations of herbaceous plants and soils at four Pb-Zn mining sites in Yunnan, China. 50 herbaceous plant samples of 9 plant species from 4 families and 50 soil samples were collected and then ana1yzed for the tota1 concentrations of Pb, Cd, and Zn. The results showed that the average concentrations of Pb, Cd, and Zn in soil samples were 3772.83, 168.81, and 5385.65 mg/kg, respectively. The average concentrations of Pb, Cd, and Zn were 395.68, 28.14, and 1664.20 mg/kg in the shoots, and 924.12, 57.25 , and 1778.75 mg/kg in the roots, respectively. Heterospecific plants at the same site and conspecific plants at various sites had different average levels of Pb, Cd, and Zn, both in the shoots and the roots. Enrichment coefficients of Pb, Cd, and Zn were greater than 1 in 2, 3, and 9 herbaceous plant samples, respectively. Translocation factors of Pb, Cd, and Zn were greater than 1 in 10, 17, and 25 herbaceous plant samples, respectively. In all 50 samples, the concentrations of Pb, Cd, and Zn between the shoots and the roots, the shoots, and the soils, and the roots and the soils had significant positive relationships.

关键词： Pb     Cd     Zn     herbaceous plants     Pb-Zn mining areas     enrichment coefficient     translocation factor    

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Water Diversion is Not to Blame for Phosphorus Enrichment in Taihu Lake

Zhiyuan Wang,Qiuwen Chen,Jianyun Zhang,Hanlu Yan,

《工程（英文）》 doi: 10.1016/j.eng.2023.07.007

摘要： The Water Diversion Project from the Yangtze River to Taihu Lake (WDYT) has been widely recognized as an urgent and effective engineering measure to increase water resources, ameliorate the hydrodynamics and water quality conditions, and safeguard the water supply of Taihu Basin. However, some previous studies claimed that WDYT has brought in allochthonous nutrients and should take responsibility for the dramatic increase in phosphorus loading of Taihu Lake in recent years, because Yangtze River has a higher average phosphorus concentration than Taihu Lake. To ensure correct public understanding and provide a critical response to the misconception about the source of phosphorus loading, we quantified contribution of water diversion from the Yangtze River to phosphorus loadings of Taihu Lake over the past twenty years. We reveal that WDYT only diverted 4.3% annually of total phosphorus input of Taihu Lake in the last decade and should not be responsible for the increase in phosphorus concentration and loading in Taihu Lake. We conclude that phosphorus input from the Huxi Region contribute 78% of phosphorus input of Taihu Lake and should be primarily responsible for the high phosphorus concentration of Taihu Lake. Our findings have provided constructive guidance for water resource management of Taihu Basin and phosphorus load control of the second stage of WDYT.
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Experimental investigation on possibility of oxygen enrichment by using gradient magnetic fields

CAI Jun, WANG Li, TONG Lige, SUN Shufeng, WU Ping

《化学科学与工程前沿（英文）》 2007年 第1卷 第3期   页码 271-276 doi: 10.1007/s11705-007-0049-x

摘要： This paper presents a novel method that uses the interception effect of gradient magnetic field on oxygen molecules to realize enrichment. The use of two opposite magnetic poles of two magnets at a certain distance forms a magnetic space having a field intensity gradient near its borders. When air injected into the magnetic space outflows from the magnetic space via its borders, oxygen molecules in the air will experience the interception effect of the gradient magnetic field, but nitrogen molecules will outflow from the magnetic space without hindrance. Thus, continuous oxygen enrichment is realized. The enrichment degree of oxygen reaches 0.65% when the inlet and outlet air flows are 40 mL/min and 20 mL/min, respectively, and the gas temperature is 298 K and the maximal product of magnetic flux density and its gradient is 563 T/m (the distance between two magnetic poles is 1 mm). When the gas temperature rises to 343 K, the enrichment degree drops to 0.32%; and when the maximal product of magnetic flux density and field intensity gradient drops to 101 T/m (the distance between two magnetic poles is 4 mm), the enrichment degree drops to 0.23%. The experimental results show that there is an optimal ratio between the inlet air flow and the outlet air flow. Under the experimental conditions in this paper, the value is about 2.0. It is demonstrated that the method presented in this paper can continuously enrich oxygen and has a higher enrichment degree than other oxygen-enrichment methods using magnetic separation.
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the effect of nitrogen on mixed culture polyhydroxyalkanoate production toward high organic loading enrichment

Zhiqiang Chen, Lizhi Zhao, Ye Ji, Qinxue Wen, Long Huang

《环境科学与工程前沿（英文）》 2019年 第13卷 第4期 doi: 10.1007/s11783-019-1135-2

摘要：

Effect of nitrogen on mixed culture PHA production was reconsidered.

Enrichment history of PHA accumulating culture was discussed.

Higher PHA content and biomass growth were achieved in presence of nitrogen.

Enrichment strategy toward higher PHA accumulation was investigated.

Microbial community succession in PHA accumulation phase was investigated.

关键词： Polyhydroxyalkanoate (PHA)     Organic loading rate     Nitrogen content     Biomass growth     Enrichment history    

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Enrichment and transfer of polycyclic aromatic hydrocarbons (PAHs) through dust aerosol generation from

《环境科学与工程前沿（英文）》 2023年 第17卷 第1期 doi: 10.1007/s11783-023-1610-7

摘要：

● Compositional patterns of PAHs in dust aerosol vary from soil during dust generation.

关键词： Dust aerosols     Enrichment factors (EFs)     Polycyclic aromatic hydrocarbons (PAHs)    

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RETRACTED ARTICLE: Momentum exchange coefficient for two jet flows mixing in a tee junction

《化学科学与工程前沿（英文）》 2023年 第17卷 第12期   页码 2161-2161 doi: 10.1007/s11705-009-0143-3

摘要： RETRACTED ARTICLE: Momentum exchange coefficient for two jet flows mixing in a tee junction

关键词： tee junction     Momentum exchange coefficient     RETRACTED    

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Mercury enrichment in

Chunhao Dai, Pufeng Qin, Zhangwei Wang, Jian Chen, Xianshan Zhang, Si Luo

《环境科学与工程前沿（英文）》 2017年 第11卷 第1期 doi: 10.1007/s11783-017-0892-z

摘要： Mercury enrichment in response to elevated atmospheric mercury concentrations in the organs of rape ( ) was investigated. Elevated soil mercury content had significant impact on mercury accumulation in rape stems, roots, seeds and seed coats. Leaf mercury in the leaves was mostly affected by atmospheric input while the stems were mostly affected by soil concentrations. Mercury in the aboveground plant tissue mainly derived from atmospheric absorption, and atmospheric mercury absorption in leaves was higher than that in the stems. Mercury enrichment in response to elevated atmospheric mercury concentrations in the organs of rape ( ) was investigated using an open top chamber fumigation experiment and a soil mercury enriched cultivation experiment. Results indicate that the mercury concentration in leaves and stems showed a significant variation under different concentrations of mercury in atmospheric and soil experiments while the concentration of mercury in roots, seeds and seed coats showed no significant variation under different atmospheric mercury concentrations. Using the function relation established by the experiment, results for atmospheric mercury sources in rape field biomass showed that atmospheric sources accounted for at least 81.81% of mercury in rape leaves and 32.29% of mercury in the stems. Therefore, mercury in the aboveground biomass predominantly derives from the absorption of atmospheric mercury.

关键词： Open top chamber     Gaseous elemental mercury (GEM)     Soil Mercury     Brassica napus    

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页岩气主要富集因素与核心区选择及评价

王社教,杨涛,张国生,李登华,陈晓明

《中国工程科学》 2012年 第14卷 第6期   页码 94-100

摘要：

影响页岩气规模开发的因素很多，最核心的因素是首先要通过建立地质评价标准，选出页岩气核心区。核心区的确定关系到在页岩气勘探初期，是否能找准页岩气最富集的目标，选择最有利地区进行勘探，突破出气关，进而实现大规模经济开发。从页岩气成藏特征、页岩气富集因素分析入手，重点探讨我国富有机质页岩的丰度、成熟度、脆性矿物含量、含气性以及盖层等关键参数及其作用。借鉴北美页岩气勘探开发和研究成果，结合我国页岩气勘探开发和研究新进展，初步建立我国页岩气核心区地质评价标准，并优选出我国南方海相页岩气的核心区，指出四川盆地南部是我国最现实的页岩气开发区。

关键词： 核心区     选区与评价     富集因素     海相页岩     页岩气    

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Experimental study of heat transfer coefficient with rectangular baffle fin of solar air heater

Foued CHABANE,Nesrine HATRAF,Noureddine MOUMMI

《能源前沿（英文）》 2014年 第8卷 第2期   页码 160-172 doi: 10.1007/s11708-014-0321-y

摘要： This paper presents an experimental analysis of a single pass solar air collector with, and without using baffle fin. The heat transfer coefficient between the absorber plate and air can be considerably increased by using artificial roughness on the bottom plate and under the absorber plate of a solar air heater duct. An experimental study has been conducted to investigate the effect of roughness and operating parameters on heat transfer. The investigation has covered the range of Reynolds number from 1259 to 2517 depending on types of the configuration of the solar collectors. Based on the experimental data, values of Nusselt number have been determined for different values of configurations and operating parameters. To determine the enhancement in heat transfer and increment in thermal efficiency, the values of Nusselt have been compared with those of smooth duct under similar flow conditions.

关键词： Nusselt number     flow rate     heat transfer     heat transfer coefficient     thermal efficiency     forced convection    

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A photolysis coefficient for characterizing the response of aqueous constituents to photolysis

David R. HOKANSON,Ke LI,R. Rhodes TRUSSELL

《环境科学与工程前沿（英文）》 2016年 第10卷 第3期   页码 428-437 doi: 10.1007/s11783-015-0780-3

摘要： UV photolysis and UV based advanced oxidation processes (AOPs) are gaining more and more attention for drinking water treatment. Quantum yield ( ) and molar absorption coefficient ( ) are the two critical parameters measuring the effectiveness of photolysis of a compound. The product of the two was proposed as a fundamental measure of a constituent’s amenability to transformation by photolysis. It was shown that this product, named the photolysis coefficient, , can be determined using standard bench tests and captures the properties that govern a constituent’s transformation when exposed to light. The development showed the photolysis coefficient to be equally useful for microbiological, inorganic and organic constituents. Values of calculated by the authors based on quantum yield and molar absorption coefficient data from the literature were summarized. Photolysis coefficients among microorganisms ranged from 8500 to more than 600000 and are far higher than for inorganic and organic compounds, which varied over a range of approximately 10 to 1000 and are much less sensitive to UV photolysis than the microorganisms.

关键词： UV photolysis     disinfection     advanced oxidation     N-nitrosodimethylamine     quantum yield     absorption coefficient    

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Effect of heat transfer coefficient of steam turbine rotor on thermal stress field under off-design condition

Jie GUO,Danmei XIE,Hengliang ZHANG,Wei JIANG,Yan ZHOU

《能源前沿（英文）》 2016年 第10卷 第1期   页码 57-64 doi: 10.1007/s11708-015-0385-3

摘要： The precise calculation of temperature and thermal stress field of steam turbine rotor under off-design conditions is of paramount significance for safe and economic operation, in which an accurate calculation of heat transfer (HT) coefficient plays a decisive role. HT coefficient changes dramatically along with working conditions. First, a finite element analysis of rotor model, applied with ordinary rotor materials, has been conducted to investigate the temperature and thermal stress difference along with the change of HT coefficient from 20 W/(m ·°C) to 20000 W/(m ·°C). Next, the differentiation between existing empirical formulas has been analyzed from the aspect of physical significance of non-dimension parameters. Finally, a verifying case of the cold startup of a 1000MW unit has been proceeded. The result shows that the accuracy of coefficient calculation when steam parameters are low has a greater influence on that of rotor temperature and thermal stress, which means a precise empirical HT coefficient formula, like the Sarkar formula is strongly recommended. When steam parameters are high and HT coefficient is larger than 10 W/(m ·°C), there will be barely any influence on the calculation of thermal stress. This research plays a constructive role in the calculation and analysis of thermal stress.

关键词： steam turbine     rotor     thermal stress     heat transfer coefficient     empirical formula    

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Dimensionality reduction and prediction of soil consolidation coefficient using random forest coupling

Hai-Bang LY; Huong-Lan Thi VU; Lanh Si HO; Binh Thai PHAM

《结构与土木工程前沿（英文）》 2022年 第16卷 第2期   页码 224-238 doi: 10.1007/s11709-022-0812-6

摘要： The consolidation coefficient of soil (Cv) is a crucial parameter used for the design of structures leaned on soft soi. In general, the Cv is determined experimentally in the laboratory. However, the experimental tests are time-consuming as well as expensive. Therefore, researchers tried several ways to determine Cv via other simple soil parameters. In this study, we developed a hybrid model of Random Forest coupling with a Relief algorithm (RF-RL) to predict the Cv of soil. To conduct this study, a database of soil parameters collected from a case study region in Vietnam was used for modeling. The performance of the proposed models was assessed via statistical indicators, namely Coefficient of determination (R2), Root Mean Squared Error (RMSE), and Mean Absolute Error (MAE). The proposal models were constructed with four sets of soil variables, including 6, 7, 8, and 13 inputs. The results revealed that all models performed well with a high performance (R2 > 0.980). Although the RF-RL model with 13 variables has the highest prediction accuracy ( R2 = 0.9869), the difference compared with other models was negligible (i.e., R2 = 0.9824, 0.9850, 0.9825 for the cases with 6, 7, 8 inputs, respectively). Thus, it can be concluded that the hybrid model of RF-RL can be employed to predict Cv based on the basic soil parameters.

关键词： soil consolidation coefficient     machine learning     random forest     Relief    

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Effective enrichment of Zn from smelting wastewater via an integrated Fe coagulation and hematite precipitation

Zhan Qu, Ting Su, Yu Chen, Xue Lin, Yang Yu, Suiyi Zhu, Xinfeng Xie, Mingxin Huo

《环境科学与工程前沿（英文）》 2019年 第13卷 第6期 doi: 10.1007/s11783-019-1178-4

摘要： 98.5% Zn was enriched from Zn-bearing smelting wastewater. 99.5% Fe was hydrothermally precipitated into hematite nanoparticles. Highly purified hematite nanoparticles were obtained. The residual Zn was 2169 mg/L, 290 times of that in smelting wastewater. Coagulation is commonly applied to treat Zn-bearing wastewater from smelting industries (smelting wastewater), and thus the Zn-bearing sludge was considerably produced, which should be solidified before safety disposal. Herein, we demonstrated a novel approach to recycle Zn effectively from smelting wastewater via an integrated Fe coagulation and hematite precipitation method. First, smelting wastewater was coagulated by adding ferric chloride to generate Fe/Zn-bearing sludge (sludge for short). Secondly, the sludge was dissolved to generate an acid solution containing 2.2 g/L of Zn and 39.2 g/L of Fe. Thirdly, the Fe/Zn-bearing solution was hydrothermally treated, and 89% of Fe was eliminated to highly purified hematite block, whereas the percentage of Zn lost was below 1.1%. Finally, the hematite precipitates were collected, and the supernatant was hydrothermally treated again with the addition of glucose. When the molar ratio of glucose to Fe in the supernatant was 1.5, over 99.5% of Fe was precipitated in hematite nanoparticles with a diameter of 10–100 nm, and the residual Fe was 21.5 mg/L. The loss of Zn was below 0.4%, and the residual Zn in the solution was 2169 mg/L, 290 times of that in the smelting wastewater. The major mechanism for Fe removal was the hydrolysis of ferric nitrate into hematite, which was promoted by nitrate consumption in glucose oxidation. This paper is the first report of an environment-friendly method for enriching Zn without generating any waste.

关键词： Smelting wastewater     Hydrothermal     Hematite precipitation     Heavy metals    

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Developing the QSPR model for predicting the storage lipid/water distribution coefficient of organic

Miao Li, Jian Li, Yuchen Lu, Cenyang Han, Xiaoxuan Wei, Guangcai Ma, Haiying Yu

《环境科学与工程前沿（英文）》 2021年 第15卷 第2期 doi: 10.1007/s11783-020-1316-z

摘要： Abstract • A predictive model for storage lipid/water distribution coefficient was developed. • The model yields outstanding fitting performance, robustness, and predictive ability. • Hydrophobic and electrostatic interactions and molecular size dominate log Klip/w. • The model can be used in a wide application domain to predict log Klip/w values. The distribution of organic compounds in stored lipids affects their migration, transformation, bioaccumulation, and toxicity in organisms. The storage lipid/water distribution coefficient (log Klip/w) of organic chemicals, which quantitatively determines such distribution, has become a key parameter to assist their ecological security and health risk. Due to the impossibility to measure Klip/w values for a huge amount of chemicals, it is necessary to develop predictive approaches. In this work, a quantitative structure-property relationship (QSPR) model for estimating log Klip/w values of small organic compounds was constructed based on 305 experimental log Klip/w values. Quantum chemical descriptors and n-octanol/water partitioning coefficient were employed to characterize the intermolecular interactions that dominate log Klip/w values. The hydrophobic and electrostatic interactions and molecular size have been found to play important roles in governing the distribution of chemicals between lipids and aqueous phases. The regression (R2 = 0.959) and validation (Q2 = 0.960) results indicate good fitting performance and robustness of the developed model. A comparison with the predictive performance of other commercial software further proves the higher accuracy and stronger predictive ability of the developed Klip/w predictive model. Thus, it can be used to predict the Klip/w values of cycloalkanes, long-chain alkanes, halides (with fluorine, chlorine, and bromine as substituents), esters (without phosphate groups), alcohols (without methoxy groups), and aromatic compounds.

关键词： Storage lipid/water distribution coefficient     log Klip/w     Organic compounds     QSPR     Quantum chemical descriptors    

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标题 作者 时间 类型 操作

Distribution, enrichment mechanism and risk assessment for fluoride in groundwater: a case study of Mihe-Weihe

期刊论文

Relationship between heavy metal concentrations of herbaceous plants and soils at four Pb-Zn mining sites in Yunnan, China

Yuan LI , Yanqun ZU , Qixian FANG , Zhaohua GAO , Christian SCHVARTZ ,

期刊论文

Water Diversion is Not to Blame for Phosphorus Enrichment in Taihu Lake

Zhiyuan Wang,Qiuwen Chen,Jianyun Zhang,Hanlu Yan,

期刊论文

Experimental investigation on possibility of oxygen enrichment by using gradient magnetic fields

CAI Jun, WANG Li, TONG Lige, SUN Shufeng, WU Ping

期刊论文

the effect of nitrogen on mixed culture polyhydroxyalkanoate production toward high organic loading enrichment

Zhiqiang Chen, Lizhi Zhao, Ye Ji, Qinxue Wen, Long Huang

期刊论文

Enrichment and transfer of polycyclic aromatic hydrocarbons (PAHs) through dust aerosol generation from

期刊论文

RETRACTED ARTICLE: Momentum exchange coefficient for two jet flows mixing in a tee junction

期刊论文

Mercury enrichment in

Chunhao Dai, Pufeng Qin, Zhangwei Wang, Jian Chen, Xianshan Zhang, Si Luo

期刊论文

页岩气主要富集因素与核心区选择及评价

王社教,杨涛,张国生,李登华,陈晓明

期刊论文

Experimental study of heat transfer coefficient with rectangular baffle fin of solar air heater

Foued CHABANE,Nesrine HATRAF,Noureddine MOUMMI

期刊论文

A photolysis coefficient for characterizing the response of aqueous constituents to photolysis

David R. HOKANSON,Ke LI,R. Rhodes TRUSSELL

期刊论文

Effect of heat transfer coefficient of steam turbine rotor on thermal stress field under off-design condition

Jie GUO,Danmei XIE,Hengliang ZHANG,Wei JIANG,Yan ZHOU

期刊论文

Dimensionality reduction and prediction of soil consolidation coefficient using random forest coupling

Hai-Bang LY; Huong-Lan Thi VU; Lanh Si HO; Binh Thai PHAM

期刊论文

Effective enrichment of Zn from smelting wastewater via an integrated Fe coagulation and hematite precipitation

Zhan Qu, Ting Su, Yu Chen, Xue Lin, Yang Yu, Suiyi Zhu, Xinfeng Xie, Mingxin Huo

期刊论文

Developing the QSPR model for predicting the storage lipid/water distribution coefficient of organic

Miao Li, Jian Li, Yuchen Lu, Cenyang Han, Xiaoxuan Wei, Guangcai Ma, Haiying Yu

期刊论文