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Source apportionment of ambient PM

Bo HAN, Xiaohui BI, Yonghua XUE, Jianhui WU, Tan ZHU, Baogui ZHANG, Jianqing DING, Yuanxin DU

《环境科学与工程前沿（英文）》 2011年 第5卷 第4期   页码 552-563 doi: 10.1007/s11783-010-0263-5

摘要： A total of 168 PM samples were collected during the year of 2005 at eight sites in the city of Wuxi in China. Fifteen chemical elements, three water-soluble ions, total carbon and organic carbon were analyzed. Six source categories were identified and their contributions to ambient PM in Wuxi were estimated using a nested chemical mass balance method that reduces the effects of colinearity on the chemical mass balance model. In addition, the concentrations of secondary aerosols, such as secondary organic carbon, sulfate and nitrate, were quantified. The spatially averaged PM was high in the spring and winter (123 μg·m and low in the summer–fall (90 μg·m ). According to the result of source apportionment, resuspended dust was the largest contributor to ambient PM , accounting for more than 50% of the PM mass. Coal combustion (14.6%) and vehicle exhaust (9.4%) were also significant source categories of ambient PM . Construction and cement dust, sulfates, secondary organic carbon, and nitrates made contributions ranging between 4.1% and 4.9%. Other source categories such as steel manufacturing dust and soil dust made low contributions to ambient PM .

关键词： source apportionment     inhalable particulate matter     nested chemical mass balance method    

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Mass and heat balance calculations and economic evaluation of an innovative biomass pyrolysis project

Quanyuan WEI, Yongshui QU, Tianwei TAN

《化学科学与工程前沿（英文）》 2011年 第5卷 第3期   页码 355-361 doi: 10.1007/s11705-010-0567-9

摘要： Biomass can be converted into flammable gas, charcoal, wood vinegar, wood tar oil and noncombustible materials with thermo-chemical pyrolysis reactions. Many factors influence these processes, such as the properties of the raw materials, and temperature control and these will affect the products that are produced. Based on the data from a straw pyrolysis demonstration project, the mass and heat balance of the biomass pyrolysis process were analyzed. The statistical product and service solutions (SPSS) statistical method was used to analyze the data which were monitored on-site. A cost-benefit analysis was then used to study the viability of commercializing the project. The analysis included net present value, internal rate of return and investment payback period. These results showed that the straw pyrolysis project has little risk, and will produce remarkable economic benefits.

关键词： mass balance     heat balance     biomass pyrolysis     economic benefit    

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Flow and mass balance analysis of eco-bio infiltration system

Marla C. MANIQUIZ, Lee-Hyung KIM, Soyoung LEE, Jiyeon CHOI

《环境科学与工程前沿（英文）》 2012年 第6卷 第5期   页码 612-619 doi: 10.1007/s11783-012-0448-1

摘要： A structured stormwater infiltration system was developed and constructed at a university campus and monitoring of storm events was performed during a one-year operation period. The flow and pollutant mass balances were analyzed and the overall efficiency of the system was assessed. While significant positive correlations were observed among rainfall, runoff and discharge volume ( = 0.93-0.99; <0.05), there was no significant correlations existed between rainfall, runoff, discharge volume and pollutant load. The system was more effective in reducing the runoff volume by more than 50% for small storm events but the difference between the runoff and discharge volume was significant even with rainfall greater than 10 mm. Results showed that the pollutant reduction rates were higher compared to the runoff volume reduction. Average pollutant reduction rates were in the range of 72% to 90% with coefficient of variation between 0.10 and 0.46. Comparable with runoff reduction, the system was more effective in reducing the pollutant load for small storm events, in the range of 80% to 100% for rainfall between 0 and 10 mm; while 65% to 80% for rainfall between 10 and 20 mm. Among the pollutant parameters, particulate matters was highly reduced by the system achieving only a maximum of 25% discharge load even after the entire runoff was completely discharged. The findings have proven the capability of the system as a tool in stormwater management achieving both flow reduction and water quality improvement.

关键词： best management practice     flow balance     low impact development     mass balance     nonpoint source     stormwater runoff    

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of typical pharmaceutical and personal care products in a wastewater treatment plant from Beijing: a massbalance study

Jie GAO,Jun HUANG,Weiwei CHEN,Bin WANG,Yujue WANG,Shubo DENG,Gang YU

《环境科学与工程前沿（英文）》 2016年 第10卷 第3期   页码 491-501 doi: 10.1007/s11783-016-0837-y

摘要： The fate and removal of pharmaceuticals and personal care products (PPCPs) in wastewater treatment plants (WWTPs) has received great attention during the last decade. Numerous data concerning concentrations in the water phase can be found in the literature, however corresponding data from sludge as well as associated mass balance calculations are very limited. In the present study, the adsorbed and dissolved concentrations of 9 PPCPs were investigated in each unit of a WWTP in Beijing, China. Based on the calculation of mass balance, the relative mass distribution and removal efficiency of each target compound was obtained at each process. The amount of PPCPs entering into the WWTP ranged from 12 g·d to 3848 g·d . Five target compounds (caffeine, chloramphenicol, bezafibrate, clofibric acid, and , -diethyl-meta-toluamide) were effectively removed, with rates of 57%–100%. Negative removal efficiencies were obtained for sulpiride, metoprolol, nalidixic acid, and carbamazepine, ranging from -19% to -79%. PPCPs mainly existed in dissolved form (≥92%) in both the raw influent and the final effluent. The sludge cake carried a much lower amount of PPCPs (17 g·d ) compared with the discharged effluent (402 g·d ). In A /O treatment tanks, the anaerobic and anoxic tanks showed good performance for PPCPs removal, and the amount of adsorbed PPCPs was increased. The results reveal that both the dissolved and the adsorbed phases should be considered when assessing the removal capacity of each A /O tank.

关键词： PPCPs     A2/O     mass balance     removal efficiency     sludge    

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Removal of arsenic by pilot-scale vertical flow constructed wetland

《环境科学与工程前沿（英文）》 2021年 第15卷 第4期 doi: 10.1007/s11783-021-1435-1

摘要：

• VFCWs are effective for the treatment of arsenic-containing wastewater.

关键词： Constructed wetland     Arsenic     Removal efficiency     Mass balance    

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Distribution of PCDD/Fs in a food waste anaerobic digestion process with biogas utilization

《环境科学与工程前沿（英文）》 2023年 第17卷 第11期 doi: 10.1007/s11783-023-1736-7

摘要：

● The PCDD/F distribution patterns of the FW-AD process were investigated.

关键词： Biological treatment     MSW classification     Mass balance     Solid digestate    

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Controlling nested wrinkle morphology through the boundary effect on narrow-band thin films

Hanyang XU, Tielin SHI, Guanglan LIAO, Qi XIA

《机械工程前沿（英文）》 2019年 第14卷 第2期   页码 235-240 doi: 10.1007/s11465-017-0458-6

摘要： We describe the formation of nested wrinkles created by the thermal mismatch between a narrow-band thin film and a compliant substrate. When a film is described as “narrow-band”, it literally means that the film band width is much shorter than its length; more precisely, it means that the width is comparable with the wavelength of the wrinkles. A silicon mask was used during film sputtering to create narrow-band films on poly (dimethylsiloxane) substrate, thus creating regular boundaries to steer local stresses and control wrinkle morphology. Disordered nano-scale wrinkles were found nested within highly ordered micro-scale sinusoidal wrinkles. The formation of nested wrinkles was explained through the amplitude and wavelength saturation of nano-scale wrinkles. The disordered morphology of nano-scale wrinkles and the highly ordered morphology of micro-scale wrinkles were explained by using the boundary effect.

关键词： nested and hierarchical wrinkles     morphology     amplitude saturation     boundary effect    

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odor compounds in water using liquid-liquid microextraction coupled with gas chromatography—positive chemicalionization-tandem mass spectrometry

Jian LU,Paul S. WILLS,P. CHRIS WILSON

《环境科学与工程前沿（英文）》 2016年 第10卷 第3期   页码 477-481 doi: 10.1007/s11783-015-0820-z

摘要： A rapid, inexpensive and laboratory friendly method was developed for analysis of off-flavor/odor compounds in fresh and salt water using gas chromatography with chemical ionization-tandem mass spectrometry. Off-flavor/odor compounds included geosmin, 2-methylisoborneol (MIB), 2-isobutyl-3-methyoxypyrazine (IBMP), and 2-isopropyl-3-methoxypyrazine (IPMP). Using this method, a single sample can be extracted within minutes using only 1 mL of organic solvent. The ion transitions for IPMP, IBMP, MIB, and geosmin were 153>121, 167>125, 152>95, and 165>109, respectively. The linearity of this method for analyzing MIB ranged from 4 to 200 ng·L , and from 0.8 to 200 ng·L for the other analytes. Method recoveries ranged from 97% to 111% and percent relative standard deviations ranged from 3% to 9%, indicating that the method is accurate, precise, and reliable.

关键词： off-flavor/odor compounds     liquid-liquid microextraction     gas chromatography-tandem mass spectrometry    

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Self-organizing method for collaboration in multi-robot system on basis of balance principle

DONG Yangbin, JIANG Jinping, HE Yan

《机械工程前沿（英文）》 2008年 第3卷 第3期   页码 283-287 doi: 10.1007/s11465-008-0044-z

摘要： By analyzing the operation characteristics of two subtasks that have resource dependency on each other, this paper demonstrates the impact of progress relation between the two subtasks on the whole task’s progress, and then puts forward a self-organizing principle called balance principle that keeps the individual profit between robots equal. Furthermore, an algorithm is designed for adjusting subtask selection on the basis of this principle. Simulation shows the validity of the algorithm on self-organizing task allocation in a multi-robot system.

关键词： algorithm     self-organizing principle     validity     Simulation     allocation    

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Dynamic visco-plastic memorial nested yield surface model of soil

ZHUANG Haiyang, CHEN Guoxing, ZHU Dinghua

《结构与土木工程前沿（英文）》 2008年 第2卷 第1期   页码 49-55 doi: 10.1007/s11709-008-0003-0

摘要： Under cyclic loadings, the plastic strain of soft soil will take place under very small shear strain. So the visco-plastic model is appropriate to be used to model the dynamic characteristics of soft soil. Based on the principles of geotechnical plastic mechanics, the incremental visco-plastic memorial nested yield surface model is developed by using the field theory of nonlinear isotropic materials and the theory of kinematical hardening modulus. At the end of anyone time increment, the inverted loading surface, the damaged surface and the initial loading surface which is tangent with the inside of inverted loading surface are memorized respectively. The kinematical behavior of yield surface is defined by using these three surfaces. The developed model in this paper is successfully implemented in ABAQUS using FORTRAN subroutine. The predicted stress-strain relationships of soft soil are compared with the test results given by dynamic triaxial tests. It is proved that the cyclic undrained stress-strain relation of soils can be fairly simulated by the model. At last, the nonlinear earthquake response of a representative soft site in Nanjing city is calculated with the dynamic behavior of soils modeled by the new developed model. The results are accordant to the earthquake response of soft site given by other scholars.

关键词： developed     dynamic     surface     inverted     appropriate    

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Mass transport mechanisms within pervaporation membranes

Yimeng Song, Fusheng Pan, Ying Li, Kaidong Quan, Zhongyi Jiang

《化学科学与工程前沿（英文）》 2019年 第13卷 第3期   页码 458-474 doi: 10.1007/s11705-018-1780-1

摘要： Pervaporation is an energy-efficient membrane technology for separating liquid molecules of similar physical properties, which may compete or combine with distillation separation technology in a number of applications. With the rapid development of new membrane materials, the pervaporation performance was significantly improved. Fundamental understanding of the mass transport mechanisms is crucial for the rational design of membrane materials and efficient intensification of pervaporation process. Based on the interactions between permeate molecules and membranes, this review focuses on two categories of mass transport mechanisms within pervaporation membranes: physical mechanism (solution-diffusion mechanism, molecular sieving mechanism) and chemical mechanism (facilitated transport mechanism). Furthermore, the optimal integration and evolution of different mass transport mechanisms are briefly introduced. Material selection and relevant applications are highlighted under the guidance of mass transport mechanisms. Finally, the current challenges and future perspectives are tentatively identified.

关键词： pervaporation membrane     mass transport mechanisms     physical mechanism     chemical mechanism    

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Peroxyacetyl nitrate measurements by thermal dissociation–chemical ionization mass spectrometry in an

Xinfeng Wang, Tao Wang, Likun Xue, Wei Nie, Zheng Xu, Steven C. N. Poon, Wenxing Wang

《环境科学与工程前沿（英文）》 2017年 第11卷 第4期 doi: 10.1007/s11783-017-0925-7

摘要： Peroxyacetyl nitrate (PAN) is an important indicator of photochemical smog and has adverse effects on human health and vegetation growth. A rapid and highly selective technique of thermal dissociation–chemical ionization mass spectrometry (TD-CIMS) was recently developed to measure the abundance of PAN in real time; however, it may be subject to artifact in the presence of nitric oxide (NO). In this study, we tested the interference of the PAN signal induced by NO, evaluated the performance of TD-CIMS in an urban environment, and investigated the concentration and formation of PAN in urban Hong Kong. NO caused a significant underestimation of the PAN signal in TD-CIMS, with the underestimation increasing sharply with NO concentration and decreasing slightly with PAN abundance. A formula was derived to link the loss of PAN signal with the concentrations of NO and PAN, which can be used for data correction in PAN measurements. The corrected PAN data from TD-CIMS were consistent with those from the commonly used gas chromatography with electron capture detection, which confirms the utility of TD-CIMS in an urban environment in which NO is abundant. In autumn of 2010, the hourly average PAN mixing ratio varied from 0.06 ppbv to 5.17 ppbv, indicating the occurrence of photochemical pollution in urban Hong Kong. The formation efficiency of PAN during pollution episodes was as high as 3.9 to 5.9 ppbv per 100 ppbv ozone. PAN levels showed a near-linear increase with NO concentration, suggesting a control policy of NO reduction for PAN pollution.

关键词： TD-CIMS     Peroxyacetyl nitrate     Interference     Photochemical pollution     Formation efficiency    

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Hybrid method integrating machine learning and particle swarm optimization for smart chemical process

Haoqin Fang, Jianzhao Zhou, Zhenyu Wang, Ziqi Qiu, Yihua Sun, Yue Lin, Ke Chen, Xiantai Zhou, Ming Pan

《化学科学与工程前沿（英文）》 2022年 第16卷 第2期   页码 274-287 doi: 10.1007/s11705-021-2043-0

摘要： Modeling and optimization is crucial to smart chemical process operations. However, a large number of nonlinearities must be considered in a typical chemical process according to complex unit operations, chemical reactions and separations. This leads to a great challenge of implementing mechanistic models into industrial-scale problems due to the resulting computational complexity. Thus, this paper presents an efficient hybrid framework of integrating machine learning and particle swarm optimization to overcome the aforementioned difficulties. An industrial propane dehydrogenation process was carried out to demonstrate the validity and efficiency of our method. Firstly, a data set was generated based on process mechanistic simulation validated by industrial data, which provides sufficient and reasonable samples for model training and testing. Secondly, four well-known machine learning methods, namely, K-nearest neighbors, decision tree, support vector machine, and artificial neural network, were compared and used to obtain the prediction models of the processes operation. All of these methods achieved highly accurate model by adjusting model parameters on the basis of high-coverage data and properly features. Finally, optimal process operations were obtained by using the particle swarm optimization approach.

关键词： smart chemical process operations     data generation     hybrid method     machine learning     particle swarm optimization    

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Simulation of blast induced crater in jointed rock mass by discontinuous deformation analysis method

Youjun NING, Xinmei AN, Jun YANG, Guowei MA,

《结构与土木工程前沿（英文）》 2010年 第4卷 第2期   页码 223-232 doi: 10.1007/s11709-010-0022-5

摘要： Rock blasting is a dynamic process accompanied with the propagations of shock waves and the dispersion of the explosion gas. This paper adopts the discontinuous deformation analysis (DDA) method to simulate the rock blasting process. A dynamic parameter adjustment and the non-reflecting boundary condition are implemented in the DDA method. The sub-block DDA method to simulate fracture problems is used. The blasting process in jointed rock mass is simulated by application of the explosion gas pressure on the expanding borehole walls and induced connected fracture surfaces around the boreholes. The blast craters with different overburdens are derived. The whole process including the explosion gas dispersion, borehole expansion, rock mass failure and cast, and the formation of the final blasting piles in rock blasting are well reproduced numerically. Parametric study for different overburdens is carried out, and the results are analyzed and discussed.

关键词： blast crater     jointed rock mass     explosion gas pressure     discontinuous deformation analysis (DDA) method    

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Standard method design considerations for semi-quantification of total naphthenic acids in oil sandsprocess affected water by mass spectrometry: A review

Kevin A. Kovalchik, Matthew S. MacLennan, Kerry M. Peru, John V. Headley, David D.Y. Chen

《化学科学与工程前沿（英文）》 2017年 第11卷 第3期   页码 497-507 doi: 10.1007/s11705-017-1652-0

摘要： Naphthenic acids are a complex class of thousands of naturally occurring aliphatic and alicyclic carboxylic acids found in oil sands bitumen and in the wastewater generated from bitumen processing. Dozens of analytical methods have been developed for the semi-quantification of total naphthenic acids in water samples. However, different methods can give different results, prompting investigation into the comparability of the many methods. A review of important methodological features for analyzing total naphthenic acids is presented and informs the design of future standard methods for the semi-quantification of total naphthenic acids using mass spectrometry. The design considerations presented are a synthesis of discussions from an Environment and Climate Change Canada (ECCC) led taskforce of 10 laboratory experts from government, industry and academia during April 2016 and subsequent discussions between University of British Columbia and ECCC representatives. Matters considered are: extraction method, solvent, pH, and temperature; analysis instrumentation and resolution; choice of calibration standards; use of surrogate and internal standards; and use of online or offline separation prior to analysis. The design considerations are amenable to both time-of-flight and Orbitrap mass spectrometers.

关键词： total naphthenic acids     environmental samples     oil sands process affected water     polar organics     mass spectrometry    

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标题 作者 时间 类型 操作

Source apportionment of ambient PM

Bo HAN, Xiaohui BI, Yonghua XUE, Jianhui WU, Tan ZHU, Baogui ZHANG, Jianqing DING, Yuanxin DU

期刊论文

Mass and heat balance calculations and economic evaluation of an innovative biomass pyrolysis project

Quanyuan WEI, Yongshui QU, Tianwei TAN

期刊论文

Flow and mass balance analysis of eco-bio infiltration system

Marla C. MANIQUIZ, Lee-Hyung KIM, Soyoung LEE, Jiyeon CHOI

期刊论文

of typical pharmaceutical and personal care products in a wastewater treatment plant from Beijing: a massbalance study

Jie GAO,Jun HUANG,Weiwei CHEN,Bin WANG,Yujue WANG,Shubo DENG,Gang YU

期刊论文

Removal of arsenic by pilot-scale vertical flow constructed wetland

期刊论文

Distribution of PCDD/Fs in a food waste anaerobic digestion process with biogas utilization

期刊论文

Controlling nested wrinkle morphology through the boundary effect on narrow-band thin films

Hanyang XU, Tielin SHI, Guanglan LIAO, Qi XIA

期刊论文

odor compounds in water using liquid-liquid microextraction coupled with gas chromatography—positive chemicalionization-tandem mass spectrometry

Jian LU,Paul S. WILLS,P. CHRIS WILSON

期刊论文

Self-organizing method for collaboration in multi-robot system on basis of balance principle

DONG Yangbin, JIANG Jinping, HE Yan

期刊论文

Dynamic visco-plastic memorial nested yield surface model of soil

ZHUANG Haiyang, CHEN Guoxing, ZHU Dinghua

期刊论文

Mass transport mechanisms within pervaporation membranes

Yimeng Song, Fusheng Pan, Ying Li, Kaidong Quan, Zhongyi Jiang

期刊论文

Peroxyacetyl nitrate measurements by thermal dissociation–chemical ionization mass spectrometry in an

Xinfeng Wang, Tao Wang, Likun Xue, Wei Nie, Zheng Xu, Steven C. N. Poon, Wenxing Wang

期刊论文

Hybrid method integrating machine learning and particle swarm optimization for smart chemical process

Haoqin Fang, Jianzhao Zhou, Zhenyu Wang, Ziqi Qiu, Yihua Sun, Yue Lin, Ke Chen, Xiantai Zhou, Ming Pan

期刊论文

Simulation of blast induced crater in jointed rock mass by discontinuous deformation analysis method

Youjun NING, Xinmei AN, Jun YANG, Guowei MA,

期刊论文

Standard method design considerations for semi-quantification of total naphthenic acids in oil sandsprocess affected water by mass spectrometry: A review

Kevin A. Kovalchik, Matthew S. MacLennan, Kerry M. Peru, John V. Headley, David D.Y. Chen

期刊论文