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Concentrations and classification of HCHs and DDTs in soil from the lower reaches of the Jiulong River, China

Jiaquan ZHANG, Shihua QI, Xinli XING, Lingzhi TAN, Wei CHEN, Ying HU, Dan YANG, Chenxi WU

《环境科学与工程前沿（英文）》 2012年 第6卷 第2期   页码 177-183 doi: 10.1007/s11783-011-0354-y

摘要： Soil is an important source to other environmental media and organisms for organochlorine pesticides (OCPs) bioaccumulation. Twenty-four representative surface soil samples were collected from the lower reaches of the Jiulong River, China, in 2009. The concentrations of hexachlorocyclohexane isomers (HCHs) ranged from 0.38 to 39.52 ng·g , with a mean value of 9.51 ng·g . The concentrations of dichlorodiphenyltrichloroethanes (DDTs) and their metabolites were within the ranges of 0.94–700.99 ng·g , with a mean value of 71.17 ng·g . The concentrations of HCHs and DDTs in the soil were lower than the first grade level (50 ng·g ) of the Chinese Environmental Quality Standard (GB15618-1995). Hierarchical Cluster Analysis (HCA) and Pearson’s bivariate Correlations Analysis (PCA) were used to analyse the distribution and contamination levels of OCPs in this region. The results showed that DDTs were the major contaminants and there were no significant correlations between various OCPs concentrations and the total organic carbon (TOC) contents. A significant positive correlation was observed between HCHs and DDTs ( <0.01), which indicates that HCHs and DDTs may have similar sources and fate in the study area.

关键词： Jiulong River     hexachlorocyclohexane (HCH) and dichlorodiphenyltrichloroethan (DDT)     classification     Hierarchical Cluster Analysis (HCA)     Pearson’s bivariate Correlations Analysis (PCA)    

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Accounting for the uncertainties in the estimation of average shear wave velocity using – correlations

《结构与土木工程前沿（英文）》 2021年 第15卷 第5期   页码 1199-1208 doi: 10.1007/s11709-021-0749-1

摘要： Site-specific seismic hazard analysis is crucial for designing earthquake resistance structures, particularly in seismically active regions. Shear wave velocity ( V S) is a key parameter in such analysis, although the economy and other factors restrict its direct field measurement in many cases. Various V S–SPT– N correlations are routinely incorporated in seismic hazard analysis to estimate the value of V S. However, many uncertainties question the reliability of these estimated V S values. This paper comes up with a statistical approach to take care of such uncertainties involved in V S calculations. The measured SPT– N values from all the critical boreholes were converted into statistical parameters and passed through various correlations to estimate V S at different depths. The effect of different soil layers in the boreholes on the Vs estimation was also taken into account. Further, the average shear wave velocity of the top 30 m soil cover ( V S30) is estimated after accounting for various epistemic and aleatoric uncertainties. The scattering nature of the V S values estimated using different V S– N correlations was reduced significantly with the application of the methodology. Study results further clearly demonstrated the potential of the approach to eliminate various uncertainties involved in the estimation of V S30 using general and soil-specific correlations.

关键词： uncertainties     V S– N correlations     V S30     SPT data     statistical methodology    

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Enhancing power generation of piezoelectric bimorph device through geometrical optimization

Action NECHIBVUTE,Albert CHAWANDA,Pearson LUHANGA

《能源前沿（英文）》 2015年 第9卷 第2期   页码 246-246 doi: 10.1007/s11708-015-0360-z

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Correlations for estimating solar radiation using sunshine hours and temperature measurement in Osogbo

S. OHUNAKIN, M. S. ADARAMOLA, O. M. OYEWOLA, R. O. FAGBENLE

《能源前沿（英文）》 2013年 第7卷 第2期   页码 214-222 doi: 10.1007/s11708-013-0241-2

摘要： In this study, the global solar radiation on horizontal surface in Osogbo, Osun state, Nigeria was analyzed using 11-year data (1997–2007). Correlations using linear and quadratic expressions were developed to relate the global solar radiation on horizontal surface based on relative sunshine hours and temperature measurements for evaluating the monthly average daily global solar radiation. The calculated monthly clearness index values indicate that the prevailing weather condition in Osogbo is heavily overcast. All the developed quadratic correlations gave better correlation coefficients (0.834, 0.872 and 0.823 respectively) than the linear models. However, the Hargreaves and Samani related based quadratic model gave the best among the three developed quadratic expressions and is therefore suggested for estimating the monthly global radiation in this site and its surroundings.

关键词： global solar radiation     Hargreaves model     sunshine hour     ambient temperatures     Osogbo    

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Applicability of high dimensional model representation correlations for ignition delay times of n-heptane

Wang LIU, Jiabo ZHANG, Zhen HUANG, Dong HAN

《能源前沿（英文）》 2019年 第13卷 第2期   页码 367-376 doi: 10.1007/s11708-018-0584-9

摘要： It is difficult to predict the ignition delay times for fuels with the two-stage ignition tendency because of the existence of the nonlinear negative temperature coefficient (NTC) phenomenon at low temperature regimes. In this paper, the random sampling-high dimensional model representation (RS-HDMR) methods were employed to predict the ignition delay times of n-heptane/air mixtures, which exhibits the NTC phenomenon, over a range of initial conditions. A detailed n-heptane chemical mechanism was used to calculate the fuel ignition delay times in the adiabatic constant-pressure system, and two HDMR correlations, the global correlation and the stepwise correlations, were then constructed. Besides, the ignition delay times predicted by both types of correlations were validated against those calculated using the detailed chemical mechanism. The results showed that both correlations had a satisfactory prediction accuracy in general for the ignition delay times of the n-heptane/air mixtures and the stepwise correlations exhibited a better performance than the global correlation in each subdomain. Therefore, it is concluded that HDMR correlations are capable of predicting the ignition delay times for fuels with two-stage ignition behaviors at low-to-intermediate temperature conditions.

关键词： ignition delay     random sampling     high dimensional model representation     n-heptane     fuel kinetics    

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Indoor carbonyl compounds in an academic building in Beijing, China: concentrations and influencing factors

Chuanjia JIANG, Pengyi ZHANG

《环境科学与工程前沿（英文）》 2012年 第6卷 第2期   页码 184-194 doi: 10.1007/s11783-011-0309-3

摘要： Carbonyl compounds in indoor air are of great concern for their adverse health effects. Between February and May, 2009, concentrations of 13 carbonyl compounds were measured in an academic building in Beijing, China. Total concentration of the detected carbonyls ranged from 20.7 to 189.1 μg·m , and among them acetone and formaldehyde were the most abundant, with mean concentrations of 26.4 and 22.6 μg·m , respectively. Average indoor concentrations of other carbonyls were below 10 μg·m . Principal component analysis identified a combined effect of common indoor carbonyl sources and ventilation on indoor carbonyl levels. Diurnal variations of the carbonyl compounds were investigated in one office room, and carbonyl concentrations tended to be lower in the daytime than at night, due to enhanced ventilation. Average concentrations of carbonyl compounds in the office room were generally higher in early May than in late February, indicating the influence of temperature. Carbonyl source emission rates from both the room and human occupants were estimated during two lectures, based on one-compartment mass balance model. The influence of human occupants on indoor carbonyl concentrations varies with environmental conditions, and may become significant in the case of a large human occupancy.

关键词： carbonyl compounds     indoor air     ventilation     human occupancy     source emission rate (SER)     principal component analysis (PCA)    

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Boiling heat transfer correlations for refrigerant mixtures flowing inside micro-fin tubes

ZHANG Xiaoyan, ZHANG Xingqun, CHEN Yunguang, YUAN Xiuling

《能源前沿（英文）》 2008年 第2卷 第4期   页码 489-493 doi: 10.1007/s11708-008-0110-6

摘要： Based on experimental results of ternary non-azeotropic refrigerant mixture R417A flowing and boiling in one smooth and two internally grooved horizontal tubes with different geometrical parameters, a boiling heat transfer correlations was developed for refrigerant mixtures flowing inside micro-fin tubes by applying the enhancement factor in the present modified-Kattan model which was modified by the experimental data of R417A in a smooth tube. The comparison between the calculation and the experimental results indicates that the prediction by the present correlations is in good agreement with the experiment of refrigerant mixtures inside different micro-fin tubes with a standard deviation of ± 30% for vapor qualities below 80%.

关键词： comparison     micro-fin     calculation     transfer     prediction    

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Regional wind power forecasting model with NWP grid data optimized

Zhao WANG, Weisheng WANG, Bo WANG

《能源前沿（英文）》 2017年 第11卷 第2期   页码 175-183 doi: 10.1007/s11708-017-0471-9

摘要： Unlike the traditional fossil energy, wind, as the clean renewable energy, can reduce the emission of the greenhouse gas. To take full advantage of the environmental benefits of wind energy, wind power forecasting has to be studied to overcome the troubles brought by the variable nature of wind. Power forecasting for regional wind farm groups is the problem that many power system operators care about. The high-dimensional feature sets with redundant information are frequently encountered when dealing with this problem. In this paper, two kinds of feature set construction methods are proposed which can achieve the proper feature set either by selecting the subsets or by transforming the original variables with specific combinations. The former method selects the subset according to the criterion of minimal-redundancy-maximal-relevance (mRMR), while the latter does so based on the method of principal component analysis (PCA). A locally weighted learning method is also proposed to utilize the processed feature set to produce the power forecast results. The proposed model is simple and easy to use with parameters optimized automatically. Finally, a case study of 28 wind farms in East China is provided to verify the effectiveness of the proposed method.

关键词： regional wind power forecasting     feature set     minimal-redundancy-maximal-relevance (mRMR)     principal component analysis (PCA)     locally weighted learning model    

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Predicting non-carcinogenic hazard quotients of heavy metals in pepper (

Marzieh Mokarram, Hamid Reza Pourghasemi, Huichun Zhang

《环境科学与工程前沿（英文）》 2020年 第14卷 第6期 doi: 10.1007/s11783-020-1331-0

摘要： Abstract • There was significant absorption of heavy metals by the pepper in contaminated soils. • The target hazard quotient (THQ) indices followed the order of Pb>Zn>>Cd » Ni. • Relationships exist between contaminated plants and electromagnetic wave. • PCA and random search can select the main spectra and predict THQ for each element. Given the tendency of heavy metals to accumulate in soil and plants, the purpose of this study was to determine the contamination levels of Cd, Ni, Pb, and Zn on peppers (leaves and fruit) grown in contaminated soils in industrial centers. For this purpose, we measured the uptake of the four heavy metals by peppers grown in the heavy metal contaminated soils throughout the four growth stages: two-leaf, growth, flowering, and fruiting, and calculated various vegetation indices to evaluate the heavy metal contamination potentials. Electromagnetic waves were also applied for analyzing the responses of the target plants to various heavy metals. Based on the relevant spectral bands identified by principal component analysis (PCA) and random search methods, a regression method was then employed to determine the most optimal spectral bands for estimating the target hazard quotient (THQ). The THQ was found to be the highest in the plants contaminated by Pb (THQ= 62) and Zn (THQ= 5.07). The results of PCA and random search indicated that the spectra at the bands of b570, b650, and b760 for Pb, b400 and b1030 for Ni, b400 and b880 for Cd, and b560, b910, and b1050 for Zn were the most optimal spectra for assessing THQ. Therefore, in future studies, instead of examining the amount of heavy metals in plants by chemical analysis in the laboratory, the responses of the plants to the electromagnetic waves in the identified bands can be readily investigated in the field based on the established correlations.

关键词： Heavy metals     Plants     Target Hazard Quotient (THQ)     Principal Component Analysis (PCA)     Random search     Electromagnetic wave    

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Interaction and independence on methane oxidation of landfill cover soil among three impact factors: water, oxygen and ammonium

Pinjing HE, Na YANG, Wenjuan FANG, Fan Lü, Liming SHAO

《环境科学与工程前沿（英文）》 2011年 第5卷 第2期   页码 175-185 doi: 10.1007/s11783-011-0320-8

摘要： To understand the influence patterns and interactions of three important environmental factors, i.e. soil water content, oxygen concentration, and ammonium addition, on methane oxidation, the soils from landfill cover layers were incubated under full factorial parameter settings. In addition to the methane oxidation rate, the quantities and community structures of methanotrophs were analyzed to determine the methane oxidation capacity of the soils. Canonical correspondence analysis was utilized to distinguish the important impact factors. Water content was found to be the most important factor influencing the methane oxidation rate and Type II methanotrophs, and the optimum value was 15% (w/w), which induced methane oxidation rates 10- and 6- times greater than those observed at 5% (w/w) and 20% (w/w), respectively. Ambient oxygen conditions were more suitable for methane oxidation than 3% oxygen. The addition of of ammonium induced different effects on methane oxidation capacity when conducted at low or high water content. With regard to the methanotrophs, Type II was sensitive to the changes of water content, while Type I was influenced by oxygen content. Furthermore, the methanotrophic acidophile, , was detected in soils with a pH of 4.9, which extended their known living environments.

关键词： quantitative polymerase chain reaction (PCR)     denaturing gradient gel electrophoresis (DGGE)     principal component analysis (PCA)     canonical correspondence analysis (CCA)    

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Acute toxicity assessment of drinking water source with luminescent bacteria: Impact of environmental conditions and a case study in Luoma Lake, East China

Xuewen Yi, Zhanqi Gao, Lanhua Liu, Qian Zhu, Guanjiu Hu, Xiaohong Zhou

《环境科学与工程前沿（英文）》 2020年 第14卷 第6期 doi: 10.1007/s11783-020-1288-z

摘要： Abstract • Acute toxicity assessment was conducted in Luoma lake watershed, East China. • Impacts of environmental factors on the toxicity testing was fully evaluated. • Dissolve oxygen had a weak positive correlation with luminescence inhibition rate. Protecting the quality of lake watersheds by preventing and reducing their contamination is an effective approach to ensure the sustainability of the drinking water supply. In this study, acute toxicity assessment was conducted on the basis of acute bioluminescence inhibition assay using the marine bacterium Vibrio fischeri as the test organism and Luoma Lake drinking water source in East China as the research target. The suitable ranges of environmental factors, including pH value, organic matter, turbidity, hardness, and dissolved oxygen of water samples were evaluated for the toxicity testing of bioluminescent bacteria. The physicochemical characteristics of water samples at the selected 43 sites of Luoma Lake watershed were measured. Results showed that the variations in pH value (7.31–8.41), hardness (5–20 °d) and dissolved oxygen (4.44–11.03 mg/L) of Luoma Lake and its main inflow and outflow rivers had negligible impacts on the acute toxicity testing of V. fischeri. The luminescence inhibition rates ranged from -11.21% to 10.80% at the 43 sites. Pearson’s correlation analysis in the experiment revealed that temperature, pH value, hardness, and turbidity had no correlation with luminescence inhibition rate, whereas dissolved oxygen showed a weak statistically positive correlation with a Pearson correlation coefficient of 0.455 (p<0.05).

关键词： Bioluminescent bacteria     Acute toxicity     Pearson correlation analysis     Drinking water source     Vibrio fischeri    

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Non-negativematrix factorization based unmixing for principal component transformed hyperspectral data

Xiu-rui GENG,Lu-yan JI,Kang SUN

《信息与电子工程前沿（英文）》 2016年 第17卷 第5期   页码 403-412 doi: 10.1631/FITEE.1600028

摘要： Non-negative matrix factorization (NMF) has been widely used in mixture analysis for hyperspectral remote sensing. When used for spectral unmixing analysis, however, it has two main shortcomings: (1) since the dimensionality of hyperspectral data is usually very large, NMF tends to suffer from large computational complexity for the popular multiplicative iteration rule; (2) NMF is sensitive to noise (outliers), and thus the corrupted data will make the results of NMF meaningless. Although principal component analysis (PCA) can be used to mitigate these two problems, the transformed data will contain negative numbers, hindering the direct use of the multiplicative iteration rule of NMF. In this paper, we analyze the impact of PCA on NMF, and find that multiplicative NMF can also be applicable to data after principal component transformation. Based on this conclusion, we present a method to perform NMF in the principal component space, named ‘principal component NMF’ (PCNMF). Experimental results show that PCNMF is both accurate and time-saving.

关键词： Non-negative matrix factorization (NMF)     Principal component analysis (PCA)     Endmember     Hyperspectral    

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Exergy analysis and simulation of a 30MW cogeneration cycle

Nikhil Dev, Samsher, S. S. Kachhwaha, Rajesh Attri

《机械工程前沿（英文）》 2013年 第8卷 第2期   页码 169-180 doi: 10.1007/s11465-013-0263-9

摘要：

Cogeneration cycle is an efficient mean to recover the waste heat from the flue gases coming out of gas turbine. With the help of computer simulation, design parameters may be selected for the best performance of cogeneration cycle. In the present work a program is executed in software EES on the basis of mathematical modelling described in paper to study cogeneration cycle performance for different parameters. Results obtained are compared with the results available in literature and are found in good agreement with them. Real gas and water properties are inbuilt in the software. Results show that enthalpy of air entering the combustion chamber is higher than that of the flue gases at combustion chamber outlet. For different operative conditions, energy and exergy efficiencies follow similar trends; although, exergy efficiency values are always lower than the corresponding energy efficiency ones. From the results it is found that turbine outlet temperature (TIT) of 524°C is uniquely suited to efficient cogeneration cycle because it enables the transfer of heat from exhaust gas to the steam cycle to take place over a minimal temperature difference. This temperature range results in the maximum thermodynamic availability while operating with highest temperature and highest efficiency cogeneration cycle. Effect of cycle pressure ratio (CR), inlet air temperature (IAT) and water pressure at heat recovery steam generator (HRSG) inlet on the 30 MW cogeneration cycle is also studied.

关键词： Cogeneration cycle     air compressor     HRSG     gas turbine     regenerator     CR     IAT    

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改进的R/S方法与中国火灾数据的分析预测

付昱华,付安捷

《中国工程科学》 2004年 第6卷 第5期   页码 39-44

摘要：

讨论工程和经济学领域中的R/S分析方法（重标极差方法）的若干改进及应用。对于全国火灾起数的分析，计算赫斯特指数H时应用2种新的数据分组方法；引入赫斯特指数的差值ΔH以利于判断下一年的火灾起数是否会激增；对于已计算出的赫斯特指数H进行R/S分析，得到一组新的赫斯特指数依此类推可以得到高阶赫斯特指数及其差值H2，ΔH2，H3，ΔH3等；根据1950—1999年全国火灾起数，用R/S方法预测

关键词： R/S分析     重标极差方法     高阶赫斯特指数     全国火灾起数     预测    

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China’s policy framework for carbon capture, utilization and storage: Review, analysis, and outlook

《能源前沿（英文）》 2023年 第17卷 第3期   页码 400-411 doi: 10.1007/s11708-023-0862-z

摘要： Carbon capture, utilization, and storage (CCUS) is estimated to contribute substantial CO2 emission reduction to carbon neutrality in China. There is yet a large gap between such enormous demand and the current capacity, and thus a sound enabling environment with sufficient policy support is imperative for CCUS development. This study reviewed 59 CCUS-related policy documents issued by the Chinese government as of July 2022, and found that a supporting policy framework for CCUS is taking embryonic form in China. More than ten departments of the central government have involved CCUS in their policies, of which the State Council, the National Development and Reform Commission (NDRC), the Ministry of Science and Technology (MOST), and the Ministry of Ecological Environment (MEE) have given the greatest attention with different focuses. Specific policy terms are further analyzed following the method of content analysis and categorized into supply-, environment- and demand-type policies. The results indicate that supply-type policies are unbalanced in policy objectives, as policy terms on technology research and demonstration greatly outnumber those on other objectives, and the attention to weak links and industrial sectors is far from sufficient. Environment-type policies, especially legislations, standards, and incentives, are inadequate in pertinence and operability. Demand-type policies are absent in the current policy system but is essential to drive the demand for the CCUS technology in domestic and foreign markets. To meet the reduction demand of China’s carbon neutral goal, policies need to be tailored according to needs of each specific technology and implemented in an orderly manner with well-balanced use on multiple objectives.

关键词： carbon capture     utilization     and storage (CCUS)     policy     content analysis     China    

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标题 作者 时间 类型 操作

Concentrations and classification of HCHs and DDTs in soil from the lower reaches of the Jiulong River, China

Jiaquan ZHANG, Shihua QI, Xinli XING, Lingzhi TAN, Wei CHEN, Ying HU, Dan YANG, Chenxi WU

期刊论文

Accounting for the uncertainties in the estimation of average shear wave velocity using – correlations

期刊论文

Enhancing power generation of piezoelectric bimorph device through geometrical optimization

Action NECHIBVUTE,Albert CHAWANDA,Pearson LUHANGA

期刊论文

Correlations for estimating solar radiation using sunshine hours and temperature measurement in Osogbo

S. OHUNAKIN, M. S. ADARAMOLA, O. M. OYEWOLA, R. O. FAGBENLE

期刊论文

Applicability of high dimensional model representation correlations for ignition delay times of n-heptane

Wang LIU, Jiabo ZHANG, Zhen HUANG, Dong HAN

期刊论文

Indoor carbonyl compounds in an academic building in Beijing, China: concentrations and influencing factors

Chuanjia JIANG, Pengyi ZHANG

期刊论文

Boiling heat transfer correlations for refrigerant mixtures flowing inside micro-fin tubes

ZHANG Xiaoyan, ZHANG Xingqun, CHEN Yunguang, YUAN Xiuling

期刊论文

Regional wind power forecasting model with NWP grid data optimized

Zhao WANG, Weisheng WANG, Bo WANG

期刊论文

Predicting non-carcinogenic hazard quotients of heavy metals in pepper (

Marzieh Mokarram, Hamid Reza Pourghasemi, Huichun Zhang

期刊论文

Interaction and independence on methane oxidation of landfill cover soil among three impact factors: water, oxygen and ammonium

Pinjing HE, Na YANG, Wenjuan FANG, Fan Lü, Liming SHAO

期刊论文

Acute toxicity assessment of drinking water source with luminescent bacteria: Impact of environmental conditions and a case study in Luoma Lake, East China

Xuewen Yi, Zhanqi Gao, Lanhua Liu, Qian Zhu, Guanjiu Hu, Xiaohong Zhou

期刊论文

Non-negativematrix factorization based unmixing for principal component transformed hyperspectral data

Xiu-rui GENG,Lu-yan JI,Kang SUN

期刊论文

Exergy analysis and simulation of a 30MW cogeneration cycle

Nikhil Dev, Samsher, S. S. Kachhwaha, Rajesh Attri

期刊论文

改进的R/S方法与中国火灾数据的分析预测

付昱华,付安捷

期刊论文

China’s policy framework for carbon capture, utilization and storage: Review, analysis, and outlook

期刊论文