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ENHANCING RAINFALL-RUNOFF POLLUTION MODELING BY INCORPORATION OF NEGLECTED PHYSICAL PROCESSES

《农业科学与工程前沿（英文）》 2023年 第10卷 第4期   页码 553-565 doi: 10.15302/J-FASE-2023519

摘要：

The growing need to mitigate rainfall-runoff pollution, especially first flush, calls for accurate quantification of pollution load and the refined understanding of its spatial-temporal variation. The wash-off model has advantages in modeling rainfall-runoff pollution due to the inclusion of two key physical processes, build-up and wash-off. However, this disregards pollution load from wet precipitation and the relationship between rainfall and runoff, leading to uncertainties in model outputs. This study integrated the Soil Conservation Service curve number (SCS-CN) into the wash-off model and added pollutant load from wet precipitation to enhance the rainfall-runoff pollution modeling. The enhanced wash-off model was validated in a typical rural-residential area. The results showed that the model performed better than the established wash-off model and the commonly-used event mean concentrations method, and identified two different modes of pollution characteristics dominated by land pollution and rainfall pollution, respectively. In addition, the model simulated more accurate pollutant concentrations at high-temporal-resolution. From this, it was found that 12% of the total runoff contained 80% to 95% of the total load for chemical oxygen demand, total N, and total P, whereas it contained only 15% of the total load for NH4+-N. The enhanced model can provide deeper insights into non-point pollution mitigation.

关键词： Erhai Lake     field experiment     non-point source     pollution load     rainfall runoff     wash-off model    

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Construction Technology of Off-Site Precast Concrete Buildings

Ting Gong,Jian Yang,Hao Hu,Feng Xu

《工程管理前沿（英文）》 2015年 第2卷 第2期   页码 122-124 doi: 10.15302/J-FEM-2015039

摘要： The industrialization of building construction is gradually becoming a new choice of construction technology driven by some great advantages such as high efficiency in construction, low energy consumption and environmental friendliness. Construction management plays an important part to ensure the quality of projects. A comparison between traditional on-site and modern off-site construction methods has been conducted. The streamlining of the process including the fabrication, transportation, stacking and assembling of precast components has also been analyzed with a discussion on the BIM application in the process.

关键词： off-site construction     precast concrete     modular construction     construction management     building information model (BIM)    

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characterization of asymmetric ultrafiltration membrane for effective recovery of proteases from surimi wash

Nora’aini ALI, Fadhilati HASSAN, Sofiah HAMZAH

《化学科学与工程前沿（英文）》 2012年 第6卷 第2期   页码 184-191 doi: 10.1007/s11705-012-1288-z

摘要： The wash water generated from the surimi processing industry contains a large amount of proteases which are widely used in the food and biotechnology industries. Asymmetric polysulfone and polyethersulfone ultrafiltration (PSf-UF and PES-UF) membranes with three different polymer concentrations were screened for their abilities to recover proteases from surimi wash water. In-house fabricated membranes were prepared via a simple dry/wet phase inversion technique and were characterized in terms of permeability coefficient, membrane morphology and molecular weight cut-off (MWCO). The ability of the UF membranes to remove commercial proteases was tested at various pressures (up to 10 bars). The membrane with the best performance, 15 wt-% PSf-UF, was further tested with actual surimi wash water. The effect of the pH of the feed solution (4 to 8) in the pre-treatment stage was also evaluated to recover the highest amount of proteases. The highest retention of protease was 96% with a flux of 25.6 L/(m ·h) which was achieved with the 15 wt-% PSf-UF membrane.

关键词： membrane     ultrafiltration     proteases     surimi wash water    

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Experimental study of the influence of acid wash on cellulose pyrolysis

WANG Shurong, LIU Qian, LUO Zhongyang, CEN Kefa, LIAO Yanfen

《化学科学与工程前沿（英文）》 2007年 第1卷 第1期   页码 35-39 doi: 10.1007/s11705-007-0007-7

摘要： The analysis of microstructure and polymerization degree showed that acid wash altered the cellulose morphology and decreased the polymerization degree significantly. A series of experiments were done to study the effect of acid wash on cellulose rapid pyrolysis. Experimental results showed that under acid pretreatment, the yield of bio-oil decreased while the production of gas and char increased. With an increase in acid concentration, this trend would be further enhanced. Sulphuric acid limited the formation of bio-oil more effectively than hydrochloric acid and phosphoric acid. According to the GC-MS analysis of bio-oil, high-concentration acid wash restrained the formation of levoglucosan by catalyzing dehydration process and cross linking reaction.
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Advanced purification and comprehensive utilization of yellow phosphorous off gas

Ping NING,Xiangyu WANG

《环境科学与工程前沿（英文）》 2015年 第9卷 第2期   页码 181-189 doi: 10.1007/s11783-014-0698-1

摘要： Yellow phosphorous is an important raw material in the chemical industry. However, during the production of yellow phosphorous, high concentrations of carbon monoxide and other impurities are released. Without appropriate purification and removal, this off gas has potential to cause severe pollution problems once released. Purified yellow phosphorous off gas can be beneficially reused as a raw material in chemical production for synthesis of high value-added chemical reagents. In this paper, the significance of purification and reutilization of yellow phosphorous off gas are explored. The principles, processes, and main characteristics of the technologies for purification and reuse of yellow phosphorus off gas (including technical measurements of impurity reduction, relevant engineering cases, and public acceptance of the technologies) are summarized. In view of the existing problems and scientific development requirements, this paper proposes several recommendations for green production based on the concept of recycle economics. We conclude that advanced purification and comprehensive reutilization can be an effective solution for heavy pollution resulting from yellow phosphorous off gassing.

关键词： yellow phosphorous off gas     purification     comprehensive utilization    

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Typical off-design analytical performances of internal combustion engine cogeneration

Xiaohong HE, Ruixian CAI

《能源前沿（英文）》 2009年 第3卷 第2期   页码 184-192 doi: 10.1007/s11708-009-0007-z

摘要： Based on experimental data, typical off-design characteristic curves with corresponding formulas of internal combustion engine (ICE) are summarized and investigated. In combination with analytical solution of single-pressure heat recovery steam generator (HRSG) and influence of ambient pressure on combined heat and power (CHP) system, off-design operation regularities of ICE cogeneration are analyzed. The approach temperature difference Δ , relative steam production and superheated steam temperature decrease with the decrease in engine load. The total energy efficiency, equivalent exergy efficiency and economic exergy efficiency first increase and then decrease. Therefore, there exists an optimum value, corresponding to ICE best efficiency operating condition. It is worth emphasizing that Δ is likely to be negative in low load condition with high design steam parameter and low ICE design exhaust gas temperature. Compared with single shaft gas turbine cogeneration, Δ in ICE cogeneration is more likely to be negative. The main reason for this is that the gas turbine has an increased exhaust gas flow with the decrease in load; while ICE is on the contrary. Moreover, ICE power output and efficiency decrease with the decrease in ambient pressure. Hence, approach temperature difference, relative steam production and superheated steam temperature decrease rapidly while the cogeneration efficiencies decrease slightly. It is necessary to consider the influence of ambient conditions, especially the optimization of ICE performances at different places, on cogeneration performances.

关键词： internal combustion engine (ICE)     cogeneration     heat recovery steam generator (HRSG)     off-design     superheated steam     saturated steam     ambient pressure    

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Quantification of emission variability for off-road equipment in China based on real-world measurements

《环境科学与工程前沿（英文）》 2022年 第16卷 第2期 doi: 10.1007/s11783-021-1455-x

摘要：

• Emissions from 53 in-use diesel-fueled off-road equipment were measured.

关键词： Off-road equipment     Portable emission measurement system (PEMS)     Real-world emissions     Diesel engine    

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Development and application of an off-site maintenance system in the petrochemical industry

Ruisheng YONG, Yanbing YE, Hanbin LUO, Lieyun DING

《工程管理前沿（英文）》 2017年 第4卷 第2期   页码 111-126 doi: 10.15302/J-FEM-2017027

摘要： On-site maintenance (ONSM) is critical to ensuring the safety of equipment in the petrochemical industry. However, many accidents occur during ONSM processes because of unstable equipment, complicated work environment, and human error. To reduce congestion and exposure to hazards during on-site operations and thereby reduce the probability of accidents, off-site maintenance (OFSM) is proposed based on Energy Release Theory (ERT). The information requirements for OFSM are analyzed. A support system for OFSM, which makes use of visualization, information management, and localization capabilities, is developed. A case study utilizing OFSM and its support system for an oil-loading facility of a petrochemical company is conducted. The application results indicated that implementation of OFSM system can significantly reduce the operation risks and can improve the operation efficiency.

关键词： on-site maintenance     petrochemical industry     safety     off-site maintenance system    

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Trace analysis of off-flavor/odor compounds in water using liquid-liquid microextraction coupled with

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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Can energy storage make off-grid photovoltaic hydrogen production system more economical?

《工程管理前沿（英文）》   页码 672-694 doi: 10.1007/s42524-022-0245-x

摘要： Under the ambitious goal of carbon neutralization, photovoltaic (PV)-driven electrolytic hydrogen (PVEH) production is emerging as a promising approach to reduce carbon emission. Considering the intermittence and variability of PV power generation, the deployment of battery energy storage can smoothen the power output. However, the investment cost of battery energy storage is pertinent to non-negligible expenses. Thus, the installation of energy-storage equipment in a PVEH system is a complex trade-off problem. The primary goals of this study are to compare the engineering economics of PVEH systems with and without energy storage, and to explore time nodes when the cost of the former scenario can compete with the latter by factoring the technology learning curve. The levelized cost of hydrogen (LCOH) is a widely used economic indicator. Represented by seven areas in seven regions of China, results show that the LCOH with and without energy storage is approximately 22.23 and 20.59 yuan/kg in 2020, respectively. In addition, as technology costs drop, the LCOH of a PVEH system with energy storage will be less than that without energy storage in 2030.

关键词： hydrogen     off-grid photovoltaic     energy storage     LCOH     engineering economics    

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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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A systematic approach to ON-OFF event detection and clustering analysis of non-intrusive appliance load

Chuan Choong YANG,Chit Siang SOH,Vooi Voon YAP

《能源前沿（英文）》 2015年 第9卷 第2期   页码 231-237 doi: 10.1007/s11708-015-0358-6

摘要： The aim of non-intrusive appliance load monitoring (NIALM) is to disaggregate the energy consumption of individual electrical appliances from total power consumption utilizing non-intrusive methods. In this paper, a systematic approach to ON-OFF event detection and clustering analysis for NIALM were presented. From the aggregate power consumption data set, the data are passed through median filtering to reduce noise and prepared for the event detection algorithm. The event detection algorithm is to determine the switching of ON and OFF status of electrical appliances. The goodness-of-fit (GOF) methodology is the event detection algorithm implemented. After event detection, the events detected were paired into ON-OFF pairing appliances. The results from the ON-OFF pairing algorithm were further clustered in groups utilizing the -means clustering analysis. The -means clustering were implemented as an unsupervised learning methodology for the clustering analysis. The novelty of this paper is the determination of the time duration an electrical appliance is turned ON through combination of event detection, ON-OFF pairing and -means clustering. The results of the algorithm implementation were discussed and ideas on future work were also proposed.

关键词： non-intrusive appliance load monitoring     event detection     goodness-of-fit (GOF)     K-means clustering     ON-OFF pairing    

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Removal of multicomponent VOCs in off-gases from an oil refining wastewater treatment plant by a compost-based

Dan WU, Chunyan ZHANG, Li HAO, Changjun GENG, Xie QUAN,

《环境科学与工程前沿（英文）》 2009年 第3卷 第4期   页码 483-491 doi: 10.1007/s11783-009-0144-y

摘要： Waste gases from oil refining wastewater treatment plants are often characterized by the presence of multicomponent and various concentrations of compounds. An evaluation of the performance and feasibility of removing multicomponent volatile organic compounds (VOCs) in off-gases from oil refining wastewater treatment plants was conducted in a pilot-scale compost-based biofilter system. This system consists of two identical biofilters packed with compost and polyethylene (PE). This paper investigates the effects of various concentrations of nonmethane hydrocarbon (NMHC) and empty bed residence time (EBRT) on the removal efficiency of NMHC. Based on the experimental results and practical applications, an EBRT of 66 s was applied to the biofilter system. The removal efficiencies of NMHC were within the range of 47%―100%. At an EBRT of 66 s, the average removal efficiency of benzene, toluene, and xylene were more than 99%, 99%, and 100%, respectively. The results demonstrated that multicomponent VOCs in off-gases from the oil refining wastewater treatment plant could be successfully removed in the biofilter system, which may provide useful information concerning the design criteria and operation of full-scale biofilters.

关键词： biodegradation     volatile organic compounds (VOCs)     biofiltration     biofilter    

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Research on Microelectromagnetic Relays

LI De-sheng, LIU Ben-dong

《机械工程前沿（英文）》 2006年 第1卷 第1期   页码 111-114 doi: 10.1007/s11465-005-0013-8

摘要：

A new microelectromagnetic relay is presented and fabricated based on micromachining technology, aiming at the miniaturization and high manufacturing efficiency of electromagnetic relays. This microrelay is composed of a lower magnetic circuit, a planar exciting coil, and an upper magnetic armature. A complete magnetic circuit is composed, and the ON and OFF states are controlled by the current of the exciting coil. The dimension of this microrelay is 5 mm ? 5 mm ? 0.4 mm. The fabrication process mainly includes lithography, sputtering, electroplating, etching, sacrifice-layer technology, etc. Electromagnetic force is calculated theoretically. The calculation results are used for the optimization design of the armature and the number of turns of the exciting coil. A microelectromagnetic relay is fabricated and the initial test results are given. The resistance of the exciting coil is about 300 Ω. The switch-on state resistance is about 1.7 Ω at an exciting current of about 50 mA.

关键词： sacrifice-layer technology     OFF     complete     microelectromagnetic     Electromagnetic    

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Simultaneous removal of hydrogen sulfide and volatile organic sulfur compounds in off-gas mixture from

Shihao Sun, Tipei Jia, Kaiqi Chen, Yongzhen Peng, Liang Zhang

《环境科学与工程前沿（英文）》 2019年 第13卷 第4期 doi: 10.1007/s11783-019-1148-x

摘要：

A two-stage BTF system was established treating odorous off-gas mixture from a WWTP.

The two-stage BTF system showed resistance for the lifting load of H2S and VOSC.

Miseq Illumina sequencing showed separated functional microbial community in BTFs.

Avoiding H2S inhibition and enhancement of VOSC degradation was achieved.

Key control point was discussed to help industrial application of the system.

关键词： Odor     Two-stage bio-trickling filter process     Bio-trickling filter     Hydrogen sulfide     Volatile organic sulfur compound    

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标题 作者 时间 类型 操作

ENHANCING RAINFALL-RUNOFF POLLUTION MODELING BY INCORPORATION OF NEGLECTED PHYSICAL PROCESSES

期刊论文

Construction Technology of Off-Site Precast Concrete Buildings

Ting Gong,Jian Yang,Hao Hu,Feng Xu

期刊论文

characterization of asymmetric ultrafiltration membrane for effective recovery of proteases from surimi wash

Nora’aini ALI, Fadhilati HASSAN, Sofiah HAMZAH

期刊论文

Experimental study of the influence of acid wash on cellulose pyrolysis

WANG Shurong, LIU Qian, LUO Zhongyang, CEN Kefa, LIAO Yanfen

期刊论文

Advanced purification and comprehensive utilization of yellow phosphorous off gas

Ping NING,Xiangyu WANG

期刊论文

Typical off-design analytical performances of internal combustion engine cogeneration

Xiaohong HE, Ruixian CAI

期刊论文

Quantification of emission variability for off-road equipment in China based on real-world measurements

期刊论文

Development and application of an off-site maintenance system in the petrochemical industry

Ruisheng YONG, Yanbing YE, Hanbin LUO, Lieyun DING

期刊论文

Trace analysis of off-flavor/odor compounds in water using liquid-liquid microextraction coupled with

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

期刊论文

Can energy storage make off-grid photovoltaic hydrogen production system more economical?

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

A systematic approach to ON-OFF event detection and clustering analysis of non-intrusive appliance load

Chuan Choong YANG,Chit Siang SOH,Vooi Voon YAP

期刊论文

Removal of multicomponent VOCs in off-gases from an oil refining wastewater treatment plant by a compost-based

Dan WU, Chunyan ZHANG, Li HAO, Changjun GENG, Xie QUAN,

期刊论文

Research on Microelectromagnetic Relays

LI De-sheng, LIU Ben-dong

期刊论文

Simultaneous removal of hydrogen sulfide and volatile organic sulfur compounds in off-gas mixture from

Shihao Sun, Tipei Jia, Kaiqi Chen, Yongzhen Peng, Liang Zhang

期刊论文